Evaluation of Waste Tire Devulcanization Technologies

(INTERNAL REPORT) CENTERPLASTICS COMPOUND & ADDITIVES Feb. 2011 – M. S. Laura Fontana – Centerplastics Enterprise, Ltd Eastern Industrial Road, zip. 516127, Shiwan Town, Boluo Area, Huizhou, DongGuan, GuangDong, P. R. China PPH Chapter 1 – Introduction Approximately 25 potential devulcanization technology researchers and developers were identified throughout the world, however, only a very small number of devulcanization systems are now operating. These are primarily small-capacity systems, which are devulcanizing natural or synthetic rubbers (as opposed to devulcanizing the mixture of rubbers recovered from waste tires). The general types of devulcanization technologies identified and analyzed in the study are shown below. Technology Basis of Processing Zone of Reaction Chemical Chemicals/chemical reactions Surface of particles Ultrasonic Ultrasonic waves Throughout particles Microwave Microwaves Throughout particles Biological Microorganisms Surface of particles Other Mechanical Steam Surface of particles Key findings Reliable information and data on devulcanization of waste tire rubber are difficult to obtain due to proprietary claims, efforts to hide poor or infeasible process performance and product quality, and the limited number of technology researchers and developers and of peer-reviewed data. Reliable data relating waste tire characteristics, devulcanized rubber quality, end product performance, and production costs is scarce.  · Only a very small number of low-capacity devulcanization systems are operating in the United States (at approximately 50 Kg /hr, all R&D scale, mechanical, or ultrasonic). No proven commercial capacity units could be found that are currently devulcanizing waste tires, for example, at 500 Kg/hr or greater. The likely reasons include insufficient product quality and high costs of production.  · In terms of the potential of producing high-quality devulcanized rubbers (for example, high strength), the best technology appears to be ultrasonic, based on the current state of the art.  · Devulcanization of single rubbers has much more history than that of multi-rubber mixtures such as waste tires. Only a few companies devulcanize single formulation rubber as a result of captive conversion or merchant scrap recovery from manufacturing. The production of devulcanized rubber from home manufacturing scrap in the U. S represents about 1 to 2 percent of total U. S. rubber consumption.  · The quality of devulcanized single rubbers is higher than that of devulcanized multiple rubbers.  · Devulcanization that depends on surface devulcanization technologies (for example, chemical and mechanical) appears destined in the near term to produce low- or medium-quality devulcanized rubber material. The estimated cost for producing devulcanized materials from waste tires is $0. 3 to $0. 6/Kg  ± 30 percent, if including the cost of crumb rubber feedstock. This range of production costs is significantly greater than that of virgin rubbers. A typical tire compound contains the following constituents: Table 1. Composition of Tires Passenger Tire Constituents Common Materials Natural rubber 14 % Natural rubber Synthetic rubber 27% SBR, butadiene rubber Carbon black 28% Carbon black Steel 14%–15% Steel Fabric, fillers, accelerators, antiozonants, etc. 16%–17% Polyester, nylon, aromatic oil, coumarine resin, silica, bonding agent, stearic acid, ntioxidant, processing chemicals, sulfur, zinc oxide Truck Tire Natural rubber 27% Natural rubber Synthetic rubber 14% Synthetic rubber Carbon black 28% Carbon black Steel 14%–15% Steel Fabric, fillers, accelerators, antiozonants, etc. 16%–17% Polyester, nylon, aromatic oil, stearic acid, antioxidant, wax, processing chemicals, sulfur, zinc oxide Source: Rubber Manufacturers Association, 2004. †¢ Reclaiming is a procedure in which scrap tire rubber or vulcanized rubber waste is converted—using mechanical and thermal energy and chemicals—into a state in which it can be mixed, processed, and vulcanized again. The principle of the process is devulcanization (Franta, 1989). Historically and practically, in the concept of rubber reclaiming, devulcanization consists of the cleavage of intermolecular bonds of the chemical network, such as carbon-sulfur (C-S) and/or sulfur-sulfur (S-S) bonds, with further shortening of the chains also occurring (Rader, 1995). This description of devulcanization is different than that given below, which is limited to chemical interactions involving sulfur atoms. †¢ Reclaim is an interesting raw material as it reduces the production costs of new rubber articles, due to shorter mixing times and lower power consumption. The processing temperature is lower, and the material has a higher dimensional stability during calandering and extrusion due to the remaining three-dimensional network. The most important advantage of cured articles containing reclaim in terms of properties is an improvement of aging resistance. †¢ Devulcanization is the process of cleaving the monosulfidic, disulfidic, and polysulfidic crosslinks (carbon-sulfur or sulfur-sulfur bonds) of vulcanized rubber. Ideally, devulcanized rubber can be revulcanized with or without the use of other compounds. The different types of devulcanization processes also modify other properties of the rubbers. These processes cause diminution of some properties over those of the parent rubber. Ideally, devulcanization would yield a product that could serve as a substitute for virgin rubber, both in terms of properties and in terms of cost of manufacture. Polymers can be divided into two groups: thermoplastics and thermosetting materials. Thermoplastics soften when heated, making it possible to (re-)shape them at higher temperatures. Thermosetting materials, like rubbers, are crosslinked on heating and therefore cannot be softened or remodeled by raising the temperature. Therefore, thermosets are more difficult to recycle compared to thermoplastics. The three-dimensional network has to be broken in order to make the material (re-)processable: the so-called reclaiming process. In this process, either sulfur crosslinks connecting the polymer chains or carbon-carbon bonds in the polymer backbone are broken. The first mechanism is preferred, as the backbone of the polymer remains intact. Scission can be obtained by heat, shear or chemical reactions. Basically, processes of rupturing the rubber network by crosslink or main-chain scission can be classified into five main groups. †¢ Thermal reclaiming; †¢ Thermo-mechanical reclaiming; †¢ Mechano-chemical reclaiming; †¢ Reclaiming by radiation, and †¢ Microbial reclaiming. In actual practice, combinations of thermal and mechanical reclaiming are mostly used, with in some cases the addition of a devulcanization aid for chemical reclaiming. 1. 1-Thermal Reclaiming For this kind of processes, heat (often combined with addition of chemicals) is used to break the sulfur bonds and thus to plasticize the rubber. Hall patented in 1858 one of the oldest and most simple processes in the rubber reclaiming industry, the Heater or Pan process (Oil law). In this process, finely ground natural rubber powder is mixed with oils and reclaiming agents and treated with high or medium pressure steam at temperatures varying from 170 °C to 200 °C. The reclaiming time is long and the homogeneity of the reclaim is low, but this process is able to reclaim a large number of polymers: natural rubber (NR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR) and butyl rubber (IIR) and the equipment is rather inexpensive. The use of the heater or pan process became less popular after Marks patented the Digester or Alkali process in 1899. The fibers of the rubber scrap, remnants of the tire carcass, were first removed by mixing it with alkali, water, plasticizing oils and, if needed, chemical peptizers. The mixture was heated in a jacketed, agitator equipped autoclave to 180-210 °C. The most important disadvantage of this process is the pollution generated by the chemicals. Modifications of this process minimized the pollution, but increased the reaction times. Processes with short reaction times are for example the High Pressure Steam processes or the Engelke process. In the first process, a fiber-free, coarse ground rubber is mixed with reclaiming agents, and reclaiming is done in a high-pressure autoclave at approximately 280 °C. In the latter process, coarse ground rubber scrap is mixed with plasticizing oils and peptizers and is put into small autoclaves. The material is heated to very high temperatures for a short period of 15 minutes, after which it is lead through refiners (mills with very narrow gaps) and strainers. . 1. 1 – Steam With or Without Chemicals (Digester, DD-CR, HTDD-CR) Steam devulcanization of crumb rubber uses a steam vessel equipped with an agitator for continuous stirring of the crumb rubber while steam is being applied. There are two variants of the basis steam process, namely, â€Å"wet† and â€Å"dry. † The wet process uses caustic and water mixed with the rubber crumb, while the dry proce ss uses only steam. If necessary, various reclaiming oils may be added to the mixture in the reaction vessel. In one case, a wet process using diaryl disulfide and reclaiming oils with saturated steam at 190 °C (374 °F) was fed finely ground NR and synthetic rubber scraps. A charge of about 440 lbs. was partially devulcanized after 15 to 17 hours of processing. This process required 12 hours at ambient temperature for pre-treatment and 3 to 5 hours for steam or high temperature treatment (Adhikari, et al. , 2000). The dry process digester has the advantage of generating less pollution than the wet process. Scrap rubber containing natural and synthetic rubbers can be reclaimed by the steam digestion process. Reclaiming oil used for this process has molecular weights between 200 and 1000, consisting of benzene, alkyl benzene, and alkylate indanes. A generic processing diagram for steam devulcanization is shown in Figure A. Figure A. Schematic Diagram of a Steam Devulcanization System Devulcanized Rubber Dehydrating System Steam Reactor Rubber Crumb Chemical(s) Liquid By-Product 1. 2 – Thermo-Mechanical Reclaiming The thermo-mechanical reclaiming processes make use of shearing forces to plasticize the rubber. Energy is introduced into the materials, resulting in a significant temperature increase, high enough to cause thermal degradation. The Lancaster-Banbury process is one of the oldest processes. Fiber-free coarse ground rubber scrap is mixed with reclaiming agents and sheared in a high speed, high-pressure internal mixer. When a continuously working, multiscrew devulcanizer is used instead of the internal mixer, the process is called the Ficker reclaiming process. One of the first continuous reclaiming processes is the so-called reclaimator process. This is basically a single screw extruder that has been adapted to reclaim fibre-free rubber scrap in very short extrusion times. The short extrusion times make this method suitable for SBR, that tends to harden when longer recycling times are applied. Another mechanical reclaiming process is the De-Link process. In this process finely ground rubber powder is mixed with the De-Link masterbatch (DeVulc) : a zinc salt of dimethyldithiocarbamate and mercaptobenzothiazole in a molar ratio of 1:1 to 1:12, dispersed in thiols and activated by stearic acid, zinc oxide and sulfur. Advantages of the process are its simplicity and the fact that standard rubber equipment is used. No evidence is available to demonstrate that the De-Link process is used beyond laboratory or pilot scale. The Toyota process is another development of mechanical reclaiming. In this process a mixture of ground rubber, virgin rubber, oils and a devulcanization aid is masticated on a two-roll mill or in an extruder. Mechanical devulcanization is achieved through the repeated deformation of rubber particles under specific conditions of temperature and pressure. The result is a devulcanized rubber, ready for further processing. Toyota developed another continuous process, Toyota Gosei (TG) combining pulverization, reclaiming and deodorization. The rubber waste has to be ground to a particle size of 5-10 mm before it can be fed into a â€Å"modular screw-type reactor† with a pulverization zone and a reaction zone. The operating temperature is in the range of 100-300 °C and 100-900 rpm screw speeds are applied, the process requires about 100 Kw (kilowatts) to process 200 to 300 kg (kilograms)/hr of rubber, or approximately 0. 4 kW/kg. By manipulating screw configuration and rotational speed, and processing temperature, researchers are able to control the duration of the treatment. In this way they can, to some extent, control the properties of the devulcanizate. The TG process has been primarily, if not exclusively, used to devulcanize specific types of rubber compounds, such as NR and SBR. 1. 3 – Mechano-Chemical Reclaiming Mixing of the rubber powder with a peptizer (chemicals used to reduce the viscosity of NR) and a reclaiming agent prior to the mechanical breakdown of the material improves the reclaiming process. The devulcanization aid is supposed to selectively break the sulfur crosslinks in the rubber network. This chemical breakdown is combined with input of thermal and/or mechanical energy, as the rate of this process is sufficiently high only at higher temperatures. The most common devulcanization aids are disulfides, e. g. aryl disulfides or diphenyl sulfides, thiophenols and their zinc salts and mercaptanes. These chemical compounds are radical scavengers: they react with the radicals generated by chain- or crosslink scission and prevent recombination of the molecules. Typical concentrations for the reclaiming agents are 0. 5 to 4 wt%. Suitable peptizers are aromatic and naphthenic oils with a high boiling point. Figure B. Schematic Diagram of a Chemical Devulcanization System Devulcanization Agent Rubber Crumb Mixer Heated Extruder Devulcanized Filter Dryer Rubber Liquid By-Product Unfortunately, a detailed accounting of test materials, performance parameters, and conditions is lacking, thus inhibiting the extent of interpretation of the data. Comparisons of data are primarily limited to comparing the properties of virgin rubbers with compounds containing the virgin and devulcanized material at concentrations of about 30 percent devulcanized material. As shown by the data in the table, the properties of the mixtures containing devulcanized material are in general moderately lower than those of their virgin counterparts. The reported data reflect two different types of chemical devulcanization technologies. Table 2. Properties of Waste Tire Rubber Devulcanized Using Chemical or Chemical/Mechanical Technology Generic Technology Technology Surrogate Test Rubber Compound s % Devulc (or Ground) Mat'l Mooney Viscosity (ML-4 @ 212 °F) Tensile Strengt h (lbs/in2) 300% Modulus (lbs/ in2) Elongation to Break (%) Chemical STI-K Polymers DeLinka NR 0 61. 9 4,270 1,987 534 NR w/devulc NR 30 72. 3 4,020 2,151 489 Virgin SBR (1520) 0 96. 6 3,880 3,059 358 SBR (1520) w/devulc SBR 30 109. 2 3,580 2,923 345 Chemical/ Mechanical LandStar/ Guangzhou Research Instituteb NR 100 28. 4 680 SR 100 17. 2 514 AMRc Powder (devulc. additive) 100 23. 9 640 Tread Tire Compoundd 0 20. 3 772 28. 6 19. 7 628 Light Duty Truck Tire Compounde 0 23. 8 536 28. 6 20. 5 500 1. 4 – Reclaiming by Irradiation Bond type Dissociation energy (KJ/mol) C-C 349 C-S 302 S-S 273 Polysulfidic 253 Table 3. Typical bond energies 1. 4. 1 – Ultrasonic Rubber devulcanization by using ultrasonic energy was first discussed in Okuda and Hatano (1987). It was a batch process in which a small piece of vulcanized rubber was devulcanized using 50 kHz ultrasonic waves after treatment for 20 minutes. The process apparently could break down C-S and S-S bonds, but not carbon-carbon (C-C) bonds. The properties of the revulcanized rubber were found to be very similar to those of the original vulcanizates. One continuous process for devulcanization of rubbers is based on the use of high-power ultrasound electromagnetic radiation. This is a suitable way to recycle waste tires and waste rubbers. The ultrasonic waves, at certain levels, in the presence of pressure and heat, can quickly break up the three-dimensional network in crosslinked, vulcanized rubber. The process of ultrasonic devulcanization is very fast, simple, efficient, and it is free of solvents and chemicals. The rate of devulcanization is approximately one second. This may lead to the preferential breakage of sulfidic crosslinks in vulcanized rubbers. (Isayev, 1993; Yu. Levin, et al. , 1996; Isayev, et al. , 1997; Yun, et al. , 2001; Yun & Isayev, April 2003). Under a license from the University of Akron for the ultrasonic devulcanization technology, NFM Company of Massillon, Ohio, has built a prototype of the machine for ultrasonic devulcanization of tire and rubber products (Boron, et al. 1996; Boron, et al. , 1999). It was reported that retreaded truck tires containing 15 and 30 weight percent (percent by weight) of ultrasonicallydevulcanized carbon black-filled SBR had passed the preliminary dynamic endurance test (Boron, et al. , 1999). Extensive studies on the ultrasonic devulcanization of rubbers, and some preliminary studies on ultrasonic decrosslinking of crosslin ked plastics, showed that this continuous process allows recycling of various types of rubbers and thermosets (Isayev, 1993; Hong & Isayev, 2002 (pp. 160–168); Shim, et al. 2002; Shim & Isayev, 2003; Gonzalez-de Los Santas, et al. , 1999). As a consequence of the process, ultrasonically-devulcanized rubber becomes soft, therefore enabling this material to be reprocessed, shaped, and revulcanized in very much the same way as virgin rubber. This new technology has been used successfully in the laboratory to devulcanize ground tire rubber (commonly referred to in the industry as GRT) (Isayev, et al. , 1995; Yun, et al. , 2001; Boron, et al. , 1996), unfilled and filled rubbers N (Hong & Isayev, 2001; Yu. Levin, et al. , 1996; Isayev, et al. , 1997; Diao, et al. 1998; Shim, et al. , September 2002; Ghose & Isayev, 2003), guayule rubber (Gonzalez-de Los Santas, et al. , 1999), fluoroelastomer, ethylene vinyl acetate foam, and crosslinked polyethylene (Isayev, 1993; Isayev & Chen, 1994). After revulcanization, rubber samples exhibit good mechanical properties, which in some cases are comparable to or exceeding those of virgin vulcanizates. Structural studies of ultrasonically-treated rubber show that the breakup of chemical crosslinks is accompanied by the partial degradation of the rubber chain; that is, the C-C bonds (Isayev, et al. , 1995; Tukachinsky, et al. 1996; Yu. Levin, et al. , 1997 (pp. 641–649); Yushanov, et al. , 1998). The degree of degradation of C-C bonds can be substantial, depending on conditions. The mechanism of rubber devulcanization under ultrasonic treatment is presently not well understood, unlike the mechanism of the degradation of long-chain polymer in solutions irradiated with ultrasound (Suslick, 1988). Ultrasonic devulcanization also alters the revulcanization kinetics of rubbers. The revulcanization of devulcanized SBR appeared to be essentially different from those of virgin SBR (Yu. Levin, et al. , 1997, pp. 120–1 28). The induction period is shorter or absent for revulcanization of devulcanized SBR. This is also true for other unfilled and carbon black-filled rubbers such as ground rubber tire (GRT), SBR, natural rubber (NR), ethylene propylene diene monomer (EPDM), and butadiene rubber (BR) cured by sulfur-containing curative systems, but not for silicone rubber cured by peroxide. Ultrasonically-devulcanized rubbers consist of sol and gel. The gel portion is typically soft and has significantly lower crosslink density than that of the original vulcanizate. Due to the presence of sol and soft gel, the devulcanized rubber can flow and is subject to shaping. Crosslink density and gel fraction of ultrasonically-devulcanized rubbers were found to correlate by a universal master curve (Yushanov, et al. , 1996; Diao, et al. , 1999; Yushanov, et al. , 1998). This curve is unique for every elastomer due to its unique chemical structure. In a comparative analysis of ultrasonically reclaimed unfilled SBR, NR and EPDM rubbers, it was found that it was more difficult to reclaim EPDM than NR and SBR. Reclaiming of EPDM roofsheeting resulted in a good quality reclaim, which after revulcanization showed more or less equal mechanical properties compared to the virgin compound. The surface smoothness of the revulcanized compounds could be controlled by the process conditions. Most companies marketing ultrasonic devulcanization technologies are utilizing very similar technologies involving cold feed extruders and varying physical arrangements of ultrasonic equipment. Ultrasonic devulcanization technology is actually composed of a â€Å"devulcanization system†Ã¢â‚¬â€ namely, extrusion and ultrasonic processing. Two key differences in some cases are the equipment and materials used to generate the ultrasonic energy required for the process, and the positioning of the transducer(s) relative to the extruder. Two different arrangements of ultrasonic devulcanization systems are shown in Figures C and D. In this type of devulcanization system, size-reduced rubber particles are loaded into a hopper and are subsequently fed into an extruder. The extruder mechanically pushes and pulls the rubber. This mechanical action serves to heat the rubber particles and softens the rubber. As the softened rubber is transported through the extruder cavity, the rubber is exposed to ultrasonic energy. The resulting combination of heat, pressure, and mechanical mastication is sufficient to achieve varying degrees of devulcanization. The time constant of the devulcanization process takes place in seconds. Essentially all of the rubber entering the process is discharged from the extruder in semi-solid product stream. Process losses would be primarily those due to emissions of fine particulates or of gases, if any, generated due to the mechanical and thermal processes occurring during the devulcanization process. After exiting through the extruder die, the rubber is passed through a cooling bath and then dried. Figure C. Schematic Diagram of an Ultrasonic Devulcanization System Showing a Mid- Extruder Location for the Ultrasonic Subsystem Ultrasonic Processing Zone Cooling Bath Devulcanized Rubber Extruder Rubber Crumb Feed Hopper Figure D. Schematic Diagram of an Ultrasonic Devulcanization System Showing the Ultrasonic Subsystem Located at the Discharge End of the Extruder Ultrasonic Processing Zone Cooling Bath Devulcanized Rubber Feed Hopper Extruder Rubber Crumb Table 4. Properties of Waste Tire Rubber Devulcanized Using Ultrasonic Technology Technology Surrogate Test Rubber Compound s % Devulc or (Ground) Mat'l Mooney Viscosity (ML-4 @ 212 °F) Tensile Strength (lbs/in2) 100% Modulus (lbs/ in2) 300% Modulus (lbs/ in2) Elongation to Break (%) U of Akron SBR 1848a 0 2,415 740 780 SBR (1848) w/devulc SBRa 10 1,075 790 540 SBR (1848) w/whole train reclaima (10) 1,940 760 660 SBR (1848) w/30 mesh buffingsa (10) 1,440 780 480 100% NR (SMR CV60) & 0% SBR (23. 5% bound styrene, and Duraden 706)b 0 3,263 116 670 NR (SMR CV60) & 25% SBR (23. 5% bound styrene, and Duraden 706)b 0 1,885 123 600 NR (SMR CV60) w/devulc SBR (23. 5% bound styrene, and Duraden 706)b 25 580 123 380 NR (SMR CV60) & 50% SBR (23. 5% bound styrene, and Duraden 706)b 0 406 131 390 Technology Surrogate Test Rubber Compound s % Devulc or (Ground) Mat'l Mooney Viscosity (ML-4 @ 12 °F) Tensile Strength (lbs/in2) 100% Modulus (lbs/ in2) 300% Modulus (lbs/ in2) Elongation to Break (%) NR (SMR CV60) w/devulc SBR (23. 5% bound styrene, and Duraden 706)b 50 363 123 320 NR (SMR CV60) & 75% SBR (23. 5% bound styrene, and Duraden 706)b 0 363 145 295 NR (SMR CV60) w/devulc SBR (23. 5% bound styrene, and Duraden 706)b 75 276 131 250 100% SBR (23. 5% bound styren e, and Duraden 706)b 0 290 152 200 100% SBR (23. 5% bound styrene, and Duraden 706)b 100 290 138 180 Table 5. Percent Change from Virgin with Selected Devulcanization Rubber Formulations Test Rubber Compounds (grade) Parts or % % Devulc. or (Groun d) Mat'l. Hardnes s Shore Tear Strengt h Tensile Strengt h 100% Modulu s 300% Modulu s Elongatio n to Break Chemical STI-K Polymers DeLinka NR w/devulc NR 30 -5. 9% 8. 3% -8. 4% SBR (1520) w/devulc SBR 30 -7. 7% -4. 4% -3. 6% Kyoto Universityb Truck tire (93 NR+ 7 BR) 84 NR+ 6 BR + 20 devulc 18 8. 1% -2. 3% 2. 6% 0. 0% 74 NR+ 6 BR + 40 devulc 33 12. 9% -11. 9% 28. 2% -17. 4% 65 NR + 5 BR + 60 devulc 46 11. 3% -19. 1% 23. 1% -13. 0% LandStar/Guangzhou R Ic 100 SIR 10 + 50 devulc SIR vs. Case 1 33 4. 3% -23. 7% 6. 7% -6. 7% SIR vs. Case 2 33 6. 5% -23. 0% 11. 5% -8. 6% Tread Tire Compound 0 NR + 30 SR + 20 CIS-BR +40 AMR 28. 6 6. 7% -17. 3% -3. 0% -18. 7% Light Duty Truck Tire Compound 30 NR + 70 SR + 0 CIS-BR + 40 AMR 28. 6 1. 6% -10. 9% -13. 9% -6. 7% Retread Tire Compound c65 NR + 35 SR +40 AMR 28. 6 6. 3% -8. 6% -10. 3% -16. 8% Ultrasonic University of Akrond Versus Akrochem SBR (1848) SBR w/devulc SBR 10 -55. 5% 6. 8% -30. 8% Test Rubber Compounds (grade) Parts o r % % Devulc. or (Groun d) Mat'l. Hardnes s Shore Tear Strengt h Tensile Strengt h 100% Modulu s 300% Modulu s Elongatio n to Break SBR w/whole Tire Reclaim 10 -19. 7% 2. 7% -15. 4% SBR w/30 Mesh Buffings 10 -40. 4% 5. 4% -38. % Natural Rubber and SBR versus devulc Base 100% NR (SMR CV60) & 0% SBR (23. 5% bound styrene, and Firestone Duraden 706) 0 Add 25% SBR, 75% NR 0 -42. 2% 6. 3% -10. 4% Devulc SBR replaces SBR 25% devulc SBR, 75% NR 25 -69. 2% 0. 0% -36. 7% 50% devulc SBR, 50% NR 50 -10. 7% -5. 6% -17. 9% 75% devulc SBR, 25% NR 75 -24. 0% -10. 0% -15. 3% SBR versus devulc SBR 100% devulc SBR 100 0. 0% -9. 5% -10. 0% Heavy carbon-blacked rubber is the hardest to devulcanize, and silica, or other mineral-filled EDPM, is the easiest. Reincorporation of the devulcanized rubber is typically in the 20 to 40 percent range. Devulcanized single-product rubber applications are wide ranging. The reclaimed product may be reintroduced into the same end product or one with more tolerant performance characteristics for the devulcanized rubber. Devulcanized rubber seems to have advantages in bonding, strength, and tread integrity above the properties of crumb rubber, which acts only as a â€Å"rubber†-like filler. According to one developer of a devulcanization process, about 3 to 10 percent of the final product can be blended into virgin material before performance properties are affected. Variations of a few percent are reported by developers of devulcanization when they vary process run conditions. Run-to-run variations are normally acceptable. Devulcanized single rubber products have a much lower degree of degradation than multiple rubber mixtures with devulcanized rubber. Virgin single-grade SBR—or natural rubber replacement with devulcanized material shown by the STI-K and the University of Akron datasets —has, at worst, a reduction of 10 percent in tensile strength, modulus, or elongation. In some cases, the addition of devulcanized rubber causes a major reduction in performance of some properties, along with improvements in one or two properties (hardness and modulus). Because the modulus is the measure of deformation—that is, tension (stretching), compression (crushing), flexing (bending), or torsion (twisting). Similarly, the increase in hardness could be an improvement or detraction, depending on the application. The devulcanized rubber properties displayed are not necessarily optimized for a specific end use. Formulators will likely be able to incorporate devulcanized rubber along with other formulation components to achieve a higher level of final product performance. Key product performance variables are level of contamination, number of rubber types in the rubber mixtures, and additives used by the formulations. The effect of additives was discussed previously under â€Å"Product Characteristics. † The number of types of rubber in waste tires is one of the most important factors affecting quality of devulcanized waste tire rubber. Optimizing a devulcanization process is very difficult when more than one type of rubber is involved. Depending on the process used, process conditions, the material, and the blending level of the devulcanized rubber, most properties will be reduced by a few percent to more than two-thirds of those of the virgin material. In situations where the devulcanized rubber properties are within 10 percent of the original rubber material, blending would seem to be an attractive opportunity that offers the potential of adding a low-cost recycled substitute. The best operating model for devulcanizers of single rubber formulation is a dedicated devulcanization line (or long run) of specific rubber. Smaller volumes of single formulations require incurring extra costs for downtime and lost product caused by the cleanout between runs. The devulcanized rubber itself and some of its additives and fillers—such as carbon black— presumably add value. These fillers take the place of new additives and fillers that would otherwise be necessary. 1. 4. 2 – Microwave Microwave technology has also been proposed to devulcanize waste rubber (Fix, 1980; Novotny, et al. 1978). This process applies the heat very quickly and uniformly on the waste rubber. The method employs the application of a controlled amount of microwave energy to devulcanize a sulfur-vulcanized elastomer— containing polar groups or components—to a state in which it could be compounded and revulcanized into useful products such as hoses. The process requ ires extraordinary or substantial physical properties. On the basis of the relative bond energies of C-C, C-S, and S-S bonds, the scission of the S-S and carbon-sulfur crosslinks appeared to take place. However, the material to be used in the microwave process must be polar enough to accept energy at a rate sufficient to generate the heat necessary for devulcanization. This method is a batch process and requires expensive equipment. Figure E. Schematic Diagram of a Microwave Devulcanization System Rubber Crumb Microwave Unit Devulcanized Rubber Cooling System 1. 5 – Microbial Reclaiming Thiobacillus-bacteria are able to oxidise the sulfur in polysulfonic bonds to sulphate. This reaction is limited to a surface layer of the rubber with a thickness of less than 1 ? and the oxidation takes several weeks. The thiophilic bacteria Sulfolobus Acidocaldarius is able to split carbonsulfur bonds in a stepwise oxidation reaction of the carbon-bound sulfur into a sulfoxide, a sulfone and finally to a sulphate8, 9. The disadvantage of these processes is the low devulcanization rate. Apparently, these types of biological devulcanization processes are exclusively or primarily limited to the surface layers of the elastomers (Christiansson, et al. , 1998). This circumstance may explain the overall low rates of desulfurization based on total mass processed. Figure F. Schematic Diagram of Biological Devulcanization System Microorganisms and Host Media Mixer/ Reactor Rubber Crumb Devulcanized Rubber Dryer Filter By-Product Gases Liquid By-Product Chapter2 – Cost Analysis Given the lack of information in the literature, the cost estimates are based on a synthesis of information and data from multiple sources for a given generic type of technology; The analysis was generally performed by determining the costs (capital and operating and maintenance) of the processes and equipment described in the available literature. The cost analyses were conducted for three technologies that use different processing approaches: chemical, ultrasonic, and mechanical. * The key processing elements of each of these technologies have been previously described in this report, and they serve as the primary basis of estimating capital and operating and maintenance costs. The data in Table 6 summarize the capital costs and operating and maintenance costs for the technologies analyzed. The data for the capital cost analysis include an allowance for engineering services for the construction of the facility. The information shows that the capital costs for the processes vary from about $92,000 to about $166,000. ** Insufficient technical information and data were found during the study to enable reliable cost analyses for other devulcanization technologies. Table 6. Estimated Unit Costs for the Production of Devulcanized Rubber Item Mechanical Chemical Ultrasonic Capacity (lb/hr) 100 75 75 Capital Cost ($) 92,000 166,000 163,000 O Cost ($) 135,000 172,000 136,000 Amortized Capital and O ($) 143,000 186,000 150,000 Amortized Unit Cost ($/lb) 0. 7 1. 2 1. 0 Interest rate: 6% per year; Amortization period: 20 years Similarly, the data in the table indicate that the operating and maintenance costs for facilities of this type range from about $135,000 to $172,000. The operating cost estimates include the cost of crumb rubber feedstock for each of the processes. Based on the relative small size of the facilities, the costs of the rental of a building for processing in operating and maintenance are included. This eliminated the cost of building a structure. As shown in the Table, the estimated amortized costs for producing devulcanized rubber are: $1. 0/lb for the ultrasonic process, $1. 2/lb for the chemical process, and $0. 7/lb for the mechanical process. The analysis used an interest rate of 6 percent per year and an amortization period of 20 years. Due to uncertainties represented by the lack of detailed technical data and operating history for the technologies, the accuracy of the cost estimates is +/- 30 percent. As mentioned earlier, these costs reflect production at low capacities. Some reduction in unit cost would likely occur due to economies of larger scale production. However, estimating reduction in unit cost is difficult because of the lack of data relating to production costs to different levels of throughput capacity for particular devulcanization technologies. For the size of operations considered in this analysis, labor costs are a substantial portion of the production costs. It is very difficult, however, to estimate the magnitude of any potential reductions in unit labor costs that might occur if processing capacities were increased substantially. All circumstances considered, any estimates of commercial production costs for devulcanization of waste tire rubber are highly speculative at best. The best estimate of the study team is that perhaps production costs could be reduced by 25 to 30 percent if processing capacities were increased by a factor of approximately 5 to 10. The estimates of processing costs developed in this study do not include the costs of pollution control. The chapter lists the types of emissions that could be expected. The difficulty of permitting such a process and the cost of compliance with environmental regulations may comprise a significant barrier to the implementation of this technology. Conceivably, pollution control costs could add 10 to 30 percent to the cost of devulcanization. The difficulty of permitting—and the cost—would be a function of the type of devulcanization technology, the processing rates, and other factors. In general, the expectation is that the cost of environmental control systems for chemical devulcanization systems would be greater than that for ultrasonic or mechanical processes. The composition of rubber and additives that are used in rubber compounds in the manufacture of vulcanized rubber can and do have a dramatic effect on the properties of materials manufactured from devulcanized rubber. Apparently, the inferior properties of some poorly (inadequately) devulcanized rubber can be compensated for by the addition of chemicals and the adjustment of operating conditions, among other remedies. In many cases in the literature, this situation is not addressed or discussed. Consequently, comparing devulcanization technologies is difficult. From most of the literature descriptions of the processes, what happens to the sulfur and other vulcanization chemicals during the various processes is unclear. Chapter 3 – Environmental Analysis Little information is available in the literature on the environmental effects associated with waste tire devulcanization technologies. The lack of information apparently exists because business developers and researchers have concentrated their efforts primarily on technology improvements and achieving satisfactory properties for devulcanized rubber, an estimation of emission rates and a detailed environmental analysis are therefore not possible. However, using data and information from some other types of tire manufacturing processes (for example, extrusion of rubber) and the characteristics of vehicle tires, a qualitative analysis was performed. The environmental analysis described subsequently is limited to chemical and ultrasonic devulcanization and assumes that control of emissions would be required. 3. 1 – Chemical technology Chemical devulcanization processes are usually batch processes that involve mixing crumb rubber with chemical reactants at a specific temperature and pressure. Once the design reaction time has elapsed, the contents are then rinsed, filtered, and dried to remove any remaining unwanted chemical components. The product can then be bagged or otherwise processed for resale. A block flow diagram of a generic chemical devulcanization process is illustrated in Figure G, showing the raw material feed is crumb rubber. The crumb rubber is mixed with one or more devulcanization agents. Chemical agents identified as devulcanization agents are listed in Table 8. During processing in the batch reactor, vapors are released that must be collected and treated before release to the ambient atmosphere. Typical types of vapors that might be emitted from a batch reactor are listed in Table 9. The chemicals that would be vented from the batch reactor are dependent on the characteristics of the waste tire feedstock and on the chemical agent(s) used in devulcanizing the crumb rubber. For example, if disulfides are used in the process, they could result in formation of hydrogen sulfide (H2S) or methyl or other mercaptans (RSH). If the chemical agent orthodichlorobenzene is used, chlorinated hydrocarbons could potentially be released in the form of air emissions. Methyl iodide is volatile, and if used as a devulcanization agent, it could be vaporized. Since tire manufacturing utilizes zinc oxide and zinc carbonate, chemical devulcanization might also produce airborne metal particulates. Once the batch is fully processed, the reactor is vented. The vent gases are treated prior to release to the atmosphere. The vapors cannot be treated by vapor phase carbon because these chemicals will plate out and blind the carbon, making it ineffective. Instead, the vapor from the batch reactor needs to be thermally oxidized. At the high exit temperatures, typically as high as 2000 °F (1100 °C), the thermal oxidizer vent gases need to be cooled in a quench tower to approximately 300 °F (150 °C). Then, to remove any metals or other particulate, the vent gases are piped to a baghouse. Because of the high thermal oxidizer temperatures, methyl mercaptans (RSH) or hydrogen sulfide (H2S) from the crumb rubber is oxidized to sulfur dioxide (SO2). Therefore, downstream of the baghouse, a scrubber is required to remove sulfur dioxide (SO2), as shown in Figure G. Scrubbed vent gases are then released to the atmosphere. In addition to the scrubber vent gases described above, liquid waste is generated from the scrubber. This liquid stream contains sodium sulfate (Na2SO4). This liquid waste can be disposed in receiving waters such as a river, stream, or bay. However, discharging to receiving waters will require a significant amount of treatment equipment and eventually a permit. As seen in Figure G, the devulcanized rubber is moved from the batch reactor to a separator by a heated extruder. Liquid that drips off the devulcanized rubber is removed in the separator and eliminated by feeding it to the same thermal oxidizer as the vent gases from the batch reactor. After the liquid has dripped off the devulcanized rubber in the separator, any remaining moisture is removed in the dryer. Fired dryers are typically fueled by natural gas burners. Dryer vent gases are piped to the common thermal oxidizer. Based on the concentration of solids in the scrubber effluent, processing the scrubber effluent through a filter press to dewater the solids may be necessary and cost-effective. Filter-pressed dewatered solids are called â€Å"filter cake. Filter cake might require disposal in a hazardous waste site. Even though the waste disposal site may accept the scrubber effluent water, the economics may favor installation and use of a filter press. This is necessary to dewater the solids due to the high cost of disposal of liquid waste. Figure G. Block Flow Diagram of a Chemical Devulcan ization System Solids H2O Batch Reactor Heated Extruder Separator Crumb Rubber Devulcanization Agent 300 ° F Liquids Devulcanized Rubber Dryer Natural Gas Vapors Thermal Oxidizer Quench Tower Baghouse Natural Gas Scrubber 2000 ° F 300 ° F H2O Air Emissions Air Emissions to Atmosphere Effluent Water Table 7. Tire Raw Materials Polymers Antiozonants Natural Rubber (polyisoprene) 2,2,4-trimethyl-1,2-dihydroquinoline (polymer) Styrene-Butadiene Rubber (SBR) n,n-(1,3-dimethylbutyl)-pphenylenediamine cis-Polybutadiene copolymer paraffinic wax Vulcanizing Agents Antioxidants Sulfur Alkylphenols Tetra-methyl thiurame sulfide Resorcinol Accelerators 2,6-Diterbutylhydroquinone Diphenylguanidine Retarders 2-Mercaptobenzothiazole n-Cyclohexylthiophthalimide n-Cyclohexyl-2-benzothiazolylsulfenamide Plasticizers 2-(n-Morpholinyl)-mercaptobenzothiazole Aliphatic oil Hexamethylenetetramine Aromatic oil Activators Naphthenic oil Zinc oxide Di-(2-ethylhexyl)-phthalate Zinc carbonate Extenders Stearic acid Silica gel Carbon black Table 8. Chemical Agents Used in Chemical Tire Devulcanization Processes Triphenyl phosphine Sodium di-n-butyl phosphite Thiol-amine reagents (specifically propane-thiol/piperidine, dithiothreitol, and hexane-lthiol) Lithium aluminum hydride Phenyl lithium Methyl iodide Hydroxide with quaternary ammonium chloride as a catalyst Orthodichlorobenzene Diphenyldisulphide Diallyl disulfide Toluene, naphtha, benzene, and/or cyclohexane, etc. in the presence of sodium Diamly disulfide Dibenzyl disulfide Diphenyl disulfide Bis(alkoxy aryl) disulfides Butyl mercaptan and thiopenols Xylene thiols Phenol sulfides and disulfides Alkyl phenol sulfides (for SBR) N,N-dialkyl aryl amine sulfides (for SBR in neutral or alkaline solutions) 3. 2 – Ultrasonic technology Devulcanization by ultrasonic methods may be a continuous process (see Figure H). As the figure illustrates, crumb rubber is loaded into a hopper and is subsequently fed into an extruder. The extruder mechanically pushes and pulls the rubber. This mechanical action serves to heat the rubber particles and soften the rubber. As the softened rubber is transported through the extruder cavity, the rubber is exposed to ultrasonic energy. The resulting combination of ultrasonic energy, along with the heat, pressure, and mechanical mastication, is sufficient to achieve varying degrees of devulcanization. The exposure time to the ultrasonic energy is only seconds. Essentially all of the rubber entering the process is discharged from the extruder in a semi-solid product stream. Process losses would be primarily emissions of fine particulate or of gases, if any, resulting from the mechanical and thermal applications occurring during devulcanization. Since the typical operating temperature of an ultrasonic devulcanization reactor is about 230 °F (110 °C), less vapor emission would be expected than from chemical devulcanization. Furthermore, since no chemicals are added to break the sulfur bonds that caused vulcanization to occur, there would likely be lower air emissions. After exiting through the extruder die, the rubber is passed through a cooling bath and then dried. Vented vapors would need to be treated by one of two methods. One method would be to use a small thermal oxidizer. The design of the thermal oxidizer, baghouse, and scrubber would be similar to that described previously for chemical devulcanization. However, the physical size of the oxidizer would be smaller, and the baghouse and scrubber would be larger. A second method to treat the vent gases exiting the ultrasonic devulcanization reactor would be use of vapor phase carbon. In this method, due to the lower operating temperatures of the ultrasonic process, vent gas exiting the ultrasonic zone would have to be heated above the dew point temperature. If this elevation in temperature is not accomplished, the vent gases could condense on the surface of the carbon and thus blind the bed. In other words, adsorption sites on the surface of the carbon would be ineffective, and vent gases would exit the carbon bed untreated. If vapor phase carbon were to be used, the capital cost would be less than that of a thermal oxidizer. However, carbon is not very efficient. Weight loading can be approximately 10 weight percent—in other words, adsorbing ten pounds of vent gas contaminants for every 100 pounds of carbon used. Use of carbon will have a relatively high operating cost. Also, the disposal of spent carbon can be very expensive. This is especially true if the spent carbon requires disposal at a hazardous waste disposal site. Even if the carbon is regenerated on-site, adsorption efficiency decreases after each regeneration. Typically, carbon can only be regenerated ten times. For illustration purposes, Figure H indicates the use of vapor phase carbon. Devulcanized rubber exiting the ultrasonic processing zone has to be cooled. A common method of reducing the rubber temperature is a cooling bath. The volume of cooling water used would be significant. Cooling water may become ontaminated from the process; this effluent water leaving the cooling bath has to be treated. If an air cooler such as fin fans is used in lieu of water in the cooling bath, the volume of effluent liquid would be reduced. Another alternative would be to use a closed-loop cooling system, where the cooling water is cooled and returned to the process for reuse. If there is a buildup of contaminants, a small slipstream could be taken off and treated in a POTW, greatly reducing the amount of effluent that would otherwise require treatment. Figure H. Block Flow Diagram of an Ultrasonic Devulcanization System Ultrasonic Processing Zone Cooling Bath Devulcanized Rubber Feed Hopper Extruder Crumb Rubber Cooling Water Supply Effluent Water Heater Air Emissions Baghouse Carbon Air Emissions to Atmosphere Table 9. Potential Types of Chemical Compounds Emitted by Chemical and Ultrasonic Devulcanization Technologies Compound Probable Source Benzene Plasticizers: Aromatic oil Methylcyclohexane Plasticizers: Na phthemic oil Toluene Plasticizers: Aromatic oil Heptane Plasticizers: Aliphatic oil 4-Vinylcyclohexene Polymers: Natural Rubber (polyisoprene), styrene-butadiene rubber (SBR), cis- Polybutadiene Ethylbenzene Plasticizers: Aromatic oil Octane Plasticizers: Aliphatic oil p-Xylene Plasticizers: Aromatic oil Styrene Polymers: styrene-butadiene rubber (SBR) Nonane Plasticizers: Aliphatic oil 1,4-Cyclohexadiene-1-isopropyl-4- methyl Polymers: Natural Rubber (polyisoprene) Isopropylbenzene Plasticizers: Aromatic oil Cyclohexene-1-methyl-3-(1- methylvinyl) Polymers: Natural Rubber (polyisoprene) Propylbenzene Plasticizers: Aromatic oil Benzaldehyde Polymers: styrene-butadiene rubber (SBR) 1-isopropyl-4-methylcyclohexane (trans) Plasticizers: Naphthemic oil 1-isopropyl-4-methylcyclohexane cis) Plasticizers: Naphthemic oil 1-isopropyl-3-methylcyclohexane Plasticizers: Naphthemic oil Decane Plasticizers: Aliphatic oil Tri-isobutylene Polymers: styrene-butadiene rubber (SBR) & cis-Polybutadiene; Plasticizers: Naphthemic oil Cyclohexene-5-methyl-3-(1- methylvinyl) Polymers: Natural Rubber (polyisoprene) Indane Plasticizers: Naphthemic oil 1-Isopropyl-4-methylbenzene Plasticizers: Aromati c oil Cyclohexene-1-methyl-4-(1- methylvinyl) Polymers: Natural Rubber (polyisoprene) 1-Isopropyl-2-methylbenzene Plasticizers: Aromatic oil Dimethylstyrene Polymers: styrene-butadiene rubber (SBR) Undecane Plasticizers: Aliphatic oil Tetramethylbenzene Plasticizers: Aromatic oil 1,2,3,4-Tetrahydronaphthalene Plasticizers: Naphthemic oil 1,3-Di-isopropyl benzene Plasticizers: Aromatic oil 1,4-Di-isopropyl benzene Plasticizers: Aromatic oil Compound Probable Source 2-Isopropyl-6-methylphenol Antioxidents: Alkylphenols Cyclohexylisothiocyanate Retarders: n-Cyclohexyl-thiophthalimide Cyclododecatriene Polymers: cis-Polybutadiene Dodecane Plasticizers: Aliphatic oil Tridecane Plasticizers: Aliphatic oil Tetraisobutylene Polymers: styrene-butadiene rubber (SBR) & cis-Polybutadiene; Plasticizers: Naphthemic oil -ter-Butylstyrene Polymers: styrene-butadiene rubber (SBR) Dimethylpropylhexahydronaphthale ne Plasticizers: Naphthemic oil Tetradecane Plasticizers: Aliphatic oil Nonylbenzene Plasticizers: Aromatic oil 2,6-Di-ter-butyl-p-quinone Antioxidents: 2,6-Diterbutyl-hydroquinone Pentadecane Plasticizers: Aliphatic oil 1,6-dimethyl-4-isopropyl-1,2,3,4- tetra-hydronaphthalene Plasticiz ers: Naphthemic oil Decylbenzene Plasticizers: Aromatic oil Di-ter-butylthiophene Plasticizers: Aromatic oil Diethyl phthalate Plasticizers: Di-(2-ethylhexyl)-phthalate Hexadecane Plasticizers: Aliphatic oil ,2-Di-tolylethane Polymers: styrene-butadiene rubber (SBR) Heptadecane Plasticizers: Aliphatic oil 2,6-Di-ter-butyl-4-ethylphenol Antioxidents: Alkylphenols Octadecane Plasticizers: Aliphatic oil 1-Phenylnaphthalene Plasticizers: Aromatic oil Di-iso-butyl phthalate Plasticizers: Di-(2-ethylhexyl)-phthalate Tridecylbenzene Plasticizers: Aromatic oil Dibutyl phthalate Plasticizers: Di-(2-ethylhexyl)-phthalate Eicosane Plasticizers: Aliphatic oil Heneicosane Plasticizers: Aliphatic oil Docosane Plasticizers: Aliphatic oil Di-(2-ethylhexyl) phthalate Plasticizers: Di-(2-ethylhexyl)-phthalate Chapter 4 – Conclusions Devulcanization of specific types of rubber and/or waste tire rubber has a long history. However, only recently have limited technical data been reported in the available literature. Usually when reported, the tested properties of devulcanized rubber compose an incomplete list. This is especially true in the interpretation of how the devulcanized product would perform during compounding, in the manufactured end product, or both. Circumstantial and anecdotal evidence indicates significant technical and economic barriers to devulcanization of waste rubber. Based on the information collected in the study, is believed that the only method of achieving bulk devulcanization, as opposed to surface devulcanization, rests with ultrasonic or microwave devulcanization methods. Of these two methods of energy application, ultrasound appears to have substantially more research and development history. An important observation is that microwave technology is not an effective or efficient way to devulcanize non-polar rubber types, which collectively compose the vast majority of the mass of rubber in waste rubbers. Because of the ability to internally devulcanize cured rubber, ultrasonically devulcanized waste tire rubber may have more desirable marketing characteristics than those of surface-devulcanizing processes under similar conditions of cost and yield. The latter processes (surface devulcanizing) include mechanical, chemical, and biological processes. However, test data and applications for ultrasonically devulcanized waste rubber are lacking in the industry, along with process cost documentation. The devulcanized rubber market is most fully developed for single product materials made from manufacturing scrap that are reclaimed for reuse in the same process or in a broader specification application. The reprocessing of single rubbers depends upon being located near a large-volume rubber products company with enough scrap and enough rubber applications to justify the devulcanization step. Devulcanization of waste rubber, despite considerable research and developmental effort, is still in an early growth stage. Devulcanization lacks adequate test data and data interpretation, and it has poorly defined end product specifications without adequately justified and defined applications and uses. Research funds appear to be most available for studying devulcanization of single rubber types, as opposed to studying rubber types with complex mixtur. In applications already using crumb rubber, devulcanized rubber can have advantages if the process combines a vulcanized rubber or other compatible material to create an integrated structure. The structure must have much better properties than those imparted by the filler role that crumb rubber frequently serves.

Euthanasia Persuasive Speech Essay

Imagine a world where anyone, even the curably ill or depressed, is easily assisted in suicide. Where someone else decides when you’re life is no longer worth living. Where it is a societal expectation to die rather than receive long-term care. Ladies and Gentlemen, this is the world that awaits us if we legalise euthanasia. Euthanasia, or assisted suicide, is defined as the practice or act of ending the life of a terminally ill person, usually by lethal injection. Though there is no exact specification for what ‘terminally ill’ may pertain to. Who would this definition extend to and who would be eligible to be euthanized? Some laws state that â€Å"terminally ill† means that death will occur in a relatively short time. Others are specifically stating within six months or less. Though this definition is futile, as medical experts state it is virtually impossible to predict the life expectancy of each specific patient. As this has been realised, numerous euthanasia activists have increasingly replaced references to ‘terminal illness’ to phrases such as ‘hopelessly ill’, ‘desperately ill’, ‘incurably ill’. In Thomas E. Joiner’s journal Suicide and Life- Threatening behaviour, an article described the guidelines for assisted suicide to be for those with a hopeless condition. The definition of ‘hopeless condition’ included terminal illness, severe physical or psychological pain, physical or mental debilitation or deterioration, or a quality of life that is no longer acceptable to the individual. In 2009, over 30% of euthanasia cases were carried out without consent in Belgium. Simultaneously, the number of cases had increased dramatically, specifically 40% greater in 2009 than in 2008. Furthermore, in 77. 9% of these cases the patients had been killed without an explicit request, nor a discussion of euthanasia. It seems extremely likely that, in Belgium, physicians are killing patients on their own cognizance with no regard for legal restraints. Is euthanasia truly a ‘voluntary’ practice, as described in the law? Even the enforcement of laws seems ineffective as they have proven to do little to ensure the safety of vulnerable patients. How can we ensure that these results will not be replicated in Australia if we follow in Belgium’s footsteps? Could euthanasia be considered a ‘slippery slope to legalised murder’? When analysing medicines primary taboo, as sworn in the Hippocratic Oath, ‘I will neither give a deadly drug to anybody if they asked for it, nor will I make a suggestion to this effect’ it becomes apparent that euthanasia purely contradicts this. Doctor assistance in the death of a patient is antithetical to the moral ethos and the primary goal of medicine. Their role as healer is fundamentally incompatible with euthanasia. Furthermore, euthanasia rejects the dignity and value of human life. The existing quality-of-human-life ethic would be replaced with a utilitarian and nihilistic death culture and a pessimistic view that the answer to life’s most difficult challenges is the intentional ending of human life. Such a radical shift in morality would fire dangerous consequences. Societal pressure and acceptance of this concept would influence the decisions of those who would originally never contemplate such a decision. Vulnerable people- the elderly, the ill, the depressed- would feel pressure- real or imagined- to request an early death through euthanasia. The legalisation of euthanasia would be detrimental to the strife for survival of the ill and depressed, to the vulnerable that health-maintenance organisations wish to exterminate, to the medical profession and to the overall value of human life. By legalising euthanasia we are allowing our world to transform into the unthinkable. When will someone else decide when you’re life is no longer worth living?

Teenage Drivers Essay Example | Topics and Well Written Essays - 1500 words

Teenage Drivers - Essay Example Moreover driving under the influence of alcohol or other drugs multiplies the risks of car accidents for these teenagers. Backed up by several statistical evidences, facts, and medical researches, most of the people are of the view that children should be at least 18 years old to get a driving license. (Davis, 2005) However, many people also believe that the sweeping statement blaming all young drivers should not be made as there are only a portion of the total teenage drivers that cause the major chunk of accidents (Davis, 2005). Several people, including parents, prefer having their children be able to drive as soon as possible so as to lessen their burden of having to drive their children to schools and universities and after school events such as parties and movies. The statistics show that every year about 5500 to 6000 teenagers lose their lives in car crashes proving it to be the most common way for a teenager to lose his life (valdes-dapena, 2005). There are many factors contributing to this. Teenagers are most likely to take risks. These risks might be influenced by various sources including emotions and peer group pressure. Other stresses caused by their busy schedules, considering that a lot of teenagers in many parts of the world attend school and universities and work at the same time, also contribute to taking risks (Ipp, 1997). Moreover, the young high school or college going children, are often under the influence of alcohol and marijuana while driving. Put bluntly, beginner drivers simply lack the experience and ability required to carry out the simple looking yet complex tasks associated with everyday driving and hence controlling the vehicle at high speeds especially in response to hazards that might be done quite easily by an experienced driver, may become very difficult for young drivers. As the sun sets, adolescents behind wheels become even riskier (Ipp, 1997). The Medical Aspect Scientists at the NIH campus in Bethesda, Md., have found that the careless attitudes and rash emotions that influence teenagers' decisions are due to a crucial part of the human brain that remains undeveloped until the age of 25. This part of the brain is responsible for influencing better decision making and impulse control and is among the latest to build up (davis, 2005). This NIH research was led by Jay Giedd, chief of brain imaging in the child psychiatric unit at the National Institute of Mental Health. Jay Giedd, along with a team of professional researchers, analyzed 4000 brain scans from 2000 volunteers to record how brains develop as children grow up and mature. His analysis illustrated a very important point. An area of the brain, called the dorsal lateral prefrontal cortex, remains under developed until the age of 25 (Davis, 2005). This area helps a person to 'look further ahead' and make sound and mature decisions. Due to the slow process of this area's development, as the children's bodies grow physically, their hormones encourage more risk-taking and thrill-seeking. But as the hormones ignite the limbic system which is responsible for responding to pleasure, emotions run high. These emotions cause difficulty in making the intelligent judgments needed

Ethical Decision Making and Leadership as Portrayed in the End of the Essay

Ethical Decision Making and Leadership as Portrayed in the End of the Line Film - Essay Example This study looks into the film â€Å"End of the Line, a documentary film directed by Rupert Murray that focuses on the implications of overfishing across the world. The film is portraying how fishing in modern times is leading to ocean ecosystems destruction. The film shows that the current consumption of fish in the world is very high thereby resulting to overfishing. It shows the fishing communities in the Mediterranean who are long- established being endangered. There is also evidence that the young fishermen in Senegal can no longer compete with the international fleets whose technology is more advanced, hence depriving them the ability to feed their families. Additionally, it reveals that Newfoundland is almost running out of cod despite its fish- rich waters attracting legions of migrants in the past. Apart from these parts of the globe, the film also reveals how overfishing has caused local disparities and corporate iniquities in China, Japan, Malta, and Gibraltar. The film n ot only examines the likely adverse consequences of overfishing to the climate, marine life, and human livelihoods, but also provides potential remedies to these consequences such as reducing the number of fishing fleets. According to Food and Agriculture Organization [FAO], the fishing industry is a significant contributor to the world economy, particularly with regard to human food consumption and provision of input factors in some industrial processes. Besides, the industry is a source of livelihood to over 600 million people across the world. Sutherland and Canwell (2011, p. 28) note, fishing industry has three major sectors. The first one is the commercial sector that involves individuals and enterprises that are associated with aquaculture resources and transformations of these resources into sale products. The second sector is recreational sector that is made up of individuals and enterprises that use fishing for purposes of sport or recreation. The third sector is the tradit ional sector that comprises individuals and enterprises that use or derive fisheries resources in accordance with their respective traditions (McGowan, 2003, p. 35). Unfortunately, as it can be seen from the movie, overfishing threatens all these sectors of fishing industry. Ethical Issues in Fishing Industry Fishing industry and the policies that govern it has a wide impact to the living conditions of significant number of people in the world. Fishing is a very crucial source of employment, social and economic benefits, food, and foundation of traditions and cultures (Barnett, 2006, p. 116). Despite the realization that fisheries resources can be depleted, these resources were treated as though they are inexhaustible. However, the recent increase in demand of fish and fish products across the world has brought to light the need to consider how fisheries resources are treated (Vasil'ev, 2011, p. 30). Most expert opinions and researches have indicated that fisheries resources cannot be sustainable in the long run (Kaiser & Forsberg, 2001, p. 191). Out of these facts, ethical issues in fisheries have arisen and they relate to ecosystem and human wellbeing. Food and Agriculture Organization [FAO] (2005) has discussed the right to food, overfishing, ecosystem degradation, poverty as the main ethical issues facing fishing industry. i) Right to Food The first ethical issue in fisheries as noted by FAO is the right to food. FAO observes that fish is a major source of both nutrition and livelihood to millions of poorest people in the world (FAO, 2005, p. 9). Responding to wide spread and persistent hunger, the 1996 Rome Declaration on World Food Security and the World Food Summit Plan of Action reiterated the right of every person to sufficient food and the basic right to be free from hunger as stipulated in the

Film review Movie Example | Topics and Well Written Essays - 250 words - 2

Film - Movie Review Example Here, time stopped, and life became a pursuit of pleasure. The head characters include Kenneth Branargh, Denzel Washington, Emma Thompson, Michael Keaton and Keanu Reeves, who find the right way to play out the misunderstandings, passionate love affairs, reconciliations and renunciations (film). When the movie starts, Beatrice and her friends are relaxing, when news of the arrival of Don Pedro, the Prince of Aragon (Denzel Washington), comes. He had come to spend time at Leonato’s (Richard Briers) villa. This was after squashing an uprising organized by Don John (Keanu Reeves). . For Benedick and Beatrice, they have been acquaintances for some time, and it takes their friends’ prodding to admit their feelings to each other. She is submitted to Benedick, just as he is to her. This couple is engaging, such that their differences are unnoticeable. However, for Hero and Claudio, they have an immediate attraction, love at first sight, but still have a lot know about each other. Claudio’s love then turns into loathe, but does not tell this Hero until their wedding day, when he denounces her (film). The whole production was as though Branargh sought to come with a bizarre diversion. It could be assumed that he knew the conventional comedy routines would prompt anything, apart from laughter. For the characters, Keanu Reeves is elegant and handsome and speaks his lines with authority. Just like Claudio and Hero, Beckinsale and Claudio behave with naà ¯ve genuineness, though they usually look numb at hearing the words that they speak. In general, the movie has done Shakespeare well, and it is

Assessment Essay Example | Topics and Well Written Essays - 500 words - 9

Assessment - Essay Example Frustrating sights from yellow leaves bring disbelieve as pest and disease had invaded the some trees and spreading to others. With time, the leaves wither and fall forming a carpet of dry and crusty leaves as some trees succumb and dry up. Additionally, gusty whirlwinds introduce flames of withering serenity while carrying everything to the sky. My choice for this description paper is Pillsbury Crossing. It was with joy that I wrote about this amazing place that offered numerous positives and negatives and a mix of numerous first impressions. Whereas peacefulness and calmness were striking features of the floodplain, the nature park’s beauty is under threat from human activities (Stokes n.p). My first sentence explained the mood of the entire paragraph. The sentence ‘nature’s language whispers in my ears’ emphasize the calmness and quietness one finds in this place. Amidst the quietness is harmony from water, birds, and the wind working in inadvertent harmony. Contrasting this harmony is â€Å"grief has had her way here†. The introduction of grief presents an unpleasant tone. However, without the grief the nature would lose its relevance. Defining the tone was a daunting task, but with the tone defined, I identified and chose the right words to use. I was careful to adhere to the intended mood of the description. I defined the atmosphere as filled with â€Å"gentle harmonious tunes making it pleasant. For a person who has never been to Pillsbury Crossing, the words are compelling and it would prompt plans for a visit. However, the â€Å"frustrating sights† from my negative description reveal the ambiance as under attack by harmful and cruel elements. I also describe leaves. The positive description acknowledges them for their â€Å"attractive amber, crimson, gold, and ochre hues.† Conversely, the leaves die after â€Å"falling† to form a leave carpet on the ground. Similes and metaphors satisfactorily created numerous

Design ethics of pratice Essay Example | Topics and Well Written Essays - 1750 words

Design ethics of pratice - Essay Example This paper highlights the competing values that have played out the contemporary companies that advertise their products. In 1996, Calvin Klein also known as CK made remarkably advertisements in the televisions, and magazine, the advert was in promotion of their jeans products. The advert drew criticism from all quarter of the world given the kind of pictures that were used in the adverts, the company used picture of some young people that were posed in a provocative manner- the young people were actually nude. They made this pictures be aired in televisions attracting huge uproar of complains and castigation. Notwithstanding, CK has had a fair share of controversies surrounding their advertisement criteria, in 1980's they aired ads that saw a 15-year-old actress Brooke Shields saying, ‘Nothing comes between me and my Calvin’ (Berry 2000, p. 41). The advert becomes controversial in the sense that it is mostly concentrated around the actress private parts; this has raised eyebrows and attracted condemnation from the public. The focus of the advert on the specific parts of the actress body was perceived unethical and resulted into complains that were given then. The company staged a series of ads in 1996 that was aimed at promoting the CK jeans wear by engaging models who posed in suggestive ways. The ads began in early July and ran in several magazines that were read by those considered to be under aged. For instance, during the period of advertisement in the magazines, young girls aged 12 years got access to the pictures that were considered unethical. Many publishers, in this relation claimed that the adverts that were used by CK then bordered pornography and should not have been aired to the public. Figure A shows one of the images taken from the ad of 1996 Figure A As can be seen in the pictures, the ad exhibited a photographer shooting a young male and a female models in what appeared to be a wood-panelled basement. The shooting was coupled wit h a creepy, predator voice of the young lady asking the man who is half dressed some suggestive questions. The lady asked â€Å"Do you think you can rip off that shirt on your body?† the young man then responded and obliged to the young lady’s question by removing the shirt. She continued and commented â€Å"That's a nice body, do you work out?† at this time, the camera used in the shoot out was concentrating in the young lady’s private parts. Parent groups and children welfare organizations raised questions about the age of the participants in the campaign, many of whom looked to be under 18.  These organizations felt that the children were being coerced to appear in the shoot out under the pretence that they will be normal shooting but the whole issue changes to the nude shooting that is used for CK adverts. According to the organizations, adverts should be moderated even if they have to be suggestive about sex, the one that was used by CK went overbo ard since the shoot out was done in an environment that depicted pornography. The belief that the advert bordered on pornography is also accentuated by the fact that one can hear the photographer instructing the actress on how to look like a pornographic actress.   This public complain was taken to the department of justice and investigations were warranted to look into the possibility of the advert having violated child phonographic

Annotated Bilbliography Essay Example | Topics and Well Written Essays - 750 words

Annotated Bilbliography - Essay Example By incorporating this process, organizations will see a trend in accelerated innovation, which will be realized in operations, products, and processes. Agresti, A. (2000). Categorical Data Analysis. New York: Wiley. The book explains the use of statistical methods for categorical data and explains its importance for various applications especially in biomedical and social sciences. The book explains different methods using a variety of real data in different settings such as medical trials, environmental opinions and much more and is useful for researchers in different fields as is provides statistical methods used in evaluating and analyzing data that will be used for categorical responses. The book offers an introduction to the most important methods used in categorical data analysis and offers the latest methods for repeated measurements and other forms of clusters of categorical data that include marginal models, associated generalized estimation equation methods and mixed models that have random effects. Argyris, Chris. (1977). Organizational Learning and Management Information Systems. Accounting, Organizations and Society, 2(2), 113-123. The journal re-examines the ongoing debate concerned with the implementation crisis of management information systems considering the theory of organizational learning. The journal explains the need for information management in organizations and elaborates on the use of management information systems to achieve proper information handling. The author explains that organizational knowledge is one of the most important assets of an organization and uses management information systems to show how organizations can ensure growth through proper information handling. It explains the need of management information systems in organizations for detecting and correcting errors that occur in the information requirements of organizations and explains that recommendations made for different organizations fail because they are either in adequate or inconsistent with the organizational structures. Brown, A. (2004). Innovation Management and Contemporary Small Enterprise Research. Sydney: Edith Cowan University, Australia. The book is about the process of innovation that has become an integral and critically important activity for the businesses of present age. The author explains how the process of innovation can help the companies in attaining the maximum productivity and benefits by getting competitive edge upon their competitors. Caron, Raymond J, Sirkka, L Jarvenppa & Stoddard, Donna B. (1994). Business Reengineering at CIGNA Corporation: Experiences and Lessons Learned from the First Five Years. MIS Quarterly, 18(3), 233-250. The journal explains the uncertainty and confusion that exits concerning business reengineering and when it is effective and provides a longitudinal view of CIGNA Corporation’s experiences with business reengineering over time. The authors give an overview of CIGNA, which is an established insurance and financial services provider in the United States and the various reengineering practices it has conducted and enabled it to save large sums of money. The author explains how each fund invested in reengineering has brought returns in form of benefits as it leads to reduction of operational costs, maximizes on use of time,

Digital inspection in food industry(compuer vision) Essay

Digital inspection in food industry(compuer vision) - Essay Example Current paper explores the various aspects of foods’ digital inspection, which is commonly developed through computer vision. The requirements of this process are analyzed and its value is explained. Examples, as available in the literature, are presented so that the benefits and the risks of the specific technique are clear. It is proved that the digital inspection of foods through computer vision can be quite helpful in identifying defects in foods but also in checking the actual ingredients of foods provided to the public. This means that digital inspection, as applied using computer vision, can serve the need for testing the appropriateness of foods for consumption but also for identifying their ingredients, if they are aligned with the standards related to the particular type of food or not. 2.0 Research Questions The research questions on which this study is based can be described as follows: A) which are the key characteristics and role of digital inspection in regard t o the food industry? B) Which are the components of digital inspection with computer vision? C) Which are the phases of computer vision in digital inspection of foods? D) Which are the risks related with the use of computer vision in digital inspection of foods? 3.0 Research Methodology Literature Review has been chosen as the research methodology for exploring the various aspects of this study’s subject. More specifically, a series of articles published in academic journals has been employed for answering to the study’s research questions, as described in the previous section. Effort has been made to retrieve recent studies. In fact, the studies used have been published from 2011 up today, with an exception of 3 studies, 2 of which were published in 2004 and one was published in 2006. These studies were used, even if not quite recent, at the level they analyzed issues that need to be incorporated in this paper. 4.0 Limitations of research During the research developed for this study the following issue appeared: not all issues addressed in this study are sufficiently covered in the literature. Effort has been made to refer to as many aspects of the study’s subject as possible; however, it is possible that gaps can be identified in regard to the answers given to the study’s research questions. These gaps are identified and highlighted in the end of the study making suggestions for future research. The fact that the recent studies available for the particular subject are limited should be also highlighted; older studies have been used instead for covering this gap so that the credibility of the study is not affected. 5.0 Literature Review 5.1 Digital inspection in food industry – overview and role Digital inspection of foods, as a process, is incorporated in food engineering sector (Yam and Papadakis 2004). The specific process focuses on the analysis of specific characteristics of food so that its condition and its synthesis are checked. This type of analysis is characterized as qualitative analysis and ‘involves visual inspection and comparison of the food samples’

Rome Essay Example | Topics and Well Written Essays - 750 words

Rome - Essay Example Plagues and floods took their toll. More crucially, the aqueducts which had formed the backbone of the efficient and complex water supply system that served most of Rome fell into disrepair after barbarian raids, leading to the population shrinking towards the river Tiber and around the Campus Martius, and falling to less than 50,000 people. Into this situation the popes of Rome stepped in, creating a serviceable network of churches and ecclesiastical institutions in order to govern the city. The city was thus introduced to Christianity and soon laid claims to being the most important Christian spiritual center. But the Church was not alone in wanting to govern Rome. By 552CE, Rome came to be occupied by the Byzantine empire, and thus began a conflict of interest between the church and the Byzantine regime that was to last for the next few centuries. Under the Byzantine rule, trade, commerce and administration deteriorated, and Rome became a shadow of its former self. The Byzantine emperor Constans II visited Rome in 663 CE, only to strip the city of all its metal from buildings and statues in order to make armaments. The Byzantine city of Constantinople soon emerged to usurp all the commercial successes of Rome, and its former influence in trade in Europe and Asia. With the decimation of the aristocratic class of Rome, a huge market of luxurious goods eventually disappeared taking away prosperity from the common people of Rome, many of whom had found jobs in the trade or manufacture of luxury items. A lot of the famous Roman skills in artisanship also disappeared due this lack of market. More and more people began leaving Rome. Trade in Rome also suffered due to insecure road and maritime travel at the mercy of Germanic and barbarian tribes in what was left of the mighty Roman empire. After Pope Gregory I took over in the 6th century and began to exert more influence than the Byzantine imperial exarchs, the populace of Rome got divided into the clergy, nobility, soldiers, and the lowest class, thus introducing a sphere of Christian influence in socio-political scenario in Rome. But the Church and its members that wanted to govern Rome along with the Byzantian empire were more interested in self-aggrandizement than in the benefit of the city itself, having become too used to the luxurious ways of the erstwhile Roman elite. Even before the fall of Rome, the popes had concentrated their energies in developing their own domain at the eastern edge of the city far away from other Roman habitations, called the Lateran. It is to Lateran that the church limited most of its activities in Rome largely ignoring the disrepair to which the city gradually fell. The pilgrimage to the shrine of St. Peter, where the saint's holy remains were supposed to have been interred, became a sort of commercial activity around which a suburb developed after a fashion, but even the visiting pilgrims who came to pay their homage failed to make any difference to the state of Rome and its gradual decline. Even after the suzerainty of Rome to the Byzantine empire was formally over in the 800CE with the crowning of Charlemagne as Holy Roman Emperor by Pope Leo III, the papacy was not able to consolidate its hold over the city, and the Arabs sacked

Google and Education Essay Example for Free

Google and Education Essay Google is today’s era is contextual to the education. The Google application is spreading tremendously in the field of education whether it is through the Google search engine for searching different information or through the books and scholarly articles search. Children of all ages and of numerous courses from different parts of world are using the Google as an educational package. The students are finding the Google as a much promising website for searching the valuable information. Many students have participated in the Google project. Using Google Docs Spreadsheets the student aware of different educational virtues like Google Earth has provided the student about the different perspectives related to the earth. The Google has empowered the education with many descent tools like mail, calendar, Google Earth, Books, Scholarly articles and others. The Google has offered the students with its application and provide them the power of fast communication like email, instant messaging, calendar and other. The Google has made the information and knowledge to be shared all over the world speedily and effectively without any error. The Google has outspread the knowledge transfer by providing huge data storage either through books or through mails. The embedded Google presentation like power point has conceptualized the idea of knowledge transfer interactively as the presentation on slides is much better and effective than reading books. The Google images have provided the stuff related to each and every field. The Google images have provided the teachers and professors to make their presentations more effective as compared to earlier. The Google images have covered all the fields like geography, buildings and other stuffs. Earlier in making slides, the teachers and professors had to spend a lot of time. Today by the Google images, the photographs can be converted into slides very easily. This is experienced by the many of the students and scholars. The Google has provided huge area illustrations from every period and from every field whether it is related to the nature or related to the history. The Google has provided the material at the fingertips of the people. Now the people can make their slides and transparencies on their own. The Google News has given a platform for viewing the news and information of whole world. The students can get through the numerous perspectives of the knowledge. The different area of information in the world is covered by the Google through the Google news. The Google Notebook has the feature for the student as a tool of research. The student can paraphrase and refine the educational material through it. By the Google Notebook the student can share their knowledge also to their colleague and with their mentors. Even they can public their knowledge to the others also. Thus the knowledge sharing is made easy by the Google. The Google has announced to launch the Google Apps Platform in the Arizona State University and the schools which are using the Google APIs including the e-mail gateways also. This contains the tools from the Google like Gmail, Google Talk, and Google Calendar. The virtues from this pack includes the back-end infrastructure like directories, single logon platforms etc. The Google uses the effective values such as the security Assertion Markup Language to support single logon and an XML interface based on Representational State Transfer to link to directory services. These services are being used by the users frequently. These services for the educational purpose are an effective step taken by the Google to incorporate the whole knowledge sharing easy. The Google is incorporating its educational packs and services all over the world for making the education interactive and easy. The Google search engine is the most efficient tool provided by the Google up to now. One can search the whole websites according to his requirements. The different articles, bolgs and other information, needed by the students and others can be obtained easily. The people can search the whole stuff he need on the internet in every area of the world. The new updates from the different websites are included and updated by the Google frequently and regularly. This feature of updating the data resources has included by the Google which is appreciated by the scholars all over the world. The Google Earth has incorporated the users for educational purposes. The users can search the roads, geographical features, maps through the Google Earth. The student can search different locations through the Google Earth. The student can see different historical features also and take them into their studies. The Google Earth has incorporated the three-dimensional view also to locate the buildings, and other historical buildings also. The maps on the Google Earth can also be viewed and studied through the Google Earth. The Google Reader has been termed as the inbox of the web by the users. The Google Reader was termed as a must tool for the academic students. The users can find current information on the Google Reader. The student related to every discipline can find the information related to its field. The versatility of the Google Reader has incorporated different fields. It contains the information related to the medicines, history, as well as related to the geography and other fields also. This feature has made the Google Reader, a powerful tool for the education purpose. The Google Book Search has empowered the users for exploring the books written by the author in different parts of the world. The books are updated regularly by the Google. The Google Book Search option has enabled the student to read the books free of cost. The Google Book Search has incorporated numerous features like updating the list of editions, references to the Scholarly Work about the books, related articles, selected pages from the books and others. Even one can search the books according to its key words search. The Google has shown the way for exploration in education according to every perspective. The users can explore the Google as a knowledge database for their requirements. The Google has helped the education a lot. The educational knowledge provided by the Google has helped the students as well as the scholars, teachers and professors also. The different features and tools from the Google have helped the education for the growth of the students. References: 1) Max W. Fischer, Gaga Over Google: Photo Images Bring Lessons to Life, Education World. http://www. education-world. com/a_curr/voice/voice121. shtml 2) Google More†¦an Introduction to Google in Education, CUE Conference-Palm Springs, California, Monday, March 05, 2007. http://jakespeak. blogspot. com/2007/03/google-morean-introduction-to-google-in. html 3) Fontana, John, Google education app hints at plan for service, Network World, Monday, October 16 2006. http://www. allbusiness. com/technology/computer-software-programming/4092190-1. html 4) Jeff VanDrimmelen, Google and Education, February 2nd, 2007. http://www. edutechie. com/2007/02/google-and-education/ 5) Jeff VanDrimmelen, Google Reader and the Academic Community, October 31st, 2006. http://www. edutechie. com/2006/10/google-reader-and-the-academic-community/ 6) Mehran Sahami, About the Google Education Summit, 10/26/2007. http://googleblog. blogspot. com/2007/10/about-google-education-summit. html

Evidence Based Practice Essay Example for Free

Evidence Based Practice Essay This question reminded me about the famous and probably one of the most important inventors in the world, Thomas Edison. When he was trying to create his filament for his light bulb, it took him more than a thousand tries to do so. Likewise in a hospital, all the procedures and treatments that nurses do while on the job has been practiced and experimented on so the patient can receive first-class quality care from the nurses. Evidence-based nursing is a process founded on the collection, interpretation, and integration of valid, important, and applicable research. An example of this can be when a new technique or procedure has been discovered to help cure new diseases. After extensive amounts of research, the technique will be experimented on. They will perform the new technique on patients to see if the patients feel better, and like the procedure done to them. Evidence-based practice will help you explore the process of making solid clinical decisions that you must make in the hospital. New problems will arise daily, and with evidence-based practice, you are able to solve those problems in a systematic way. I believe that to do evidence-based practice needs to be done with a group or a team. Efficiency and accuracy is needed when doing evidence-based practice because in the end, the patients are the ones that need to be satisfied with the care that they are receiving. An example of the evidence based practice is as a chemo nurse, patients admitted for chemotherapy are offered pre-treatment assessment and physical and emotional support. Also, we provide a low-stress setting that helps patients and families to receive fully absorb the information and educate themselves about their disease and its treatments. As an effect to evidence-based nursing, we can now be more confident about the procedures that we do on our patients, because they have been thoroughly checked over.

Mind Body Relationship In Human Person Philosophy Essay

Mind Body Relationship In Human Person Philosophy Essay The mind-body problem has been a much discussed issue in the Philosophy of Mind. All those who undertake any study in consciousness, necessarily need to touch upon this subject. One of the unsettled puzzles is about whether consciousness is part of material or mental realm. It has challenged the scientists as well as philosophers to look for some solutions. They have proposed several theories to address the issue. Among several theories dualism and physicalism were the most discussed. There are some crucial questions regarding mind-body problem: such as; how do they interact, whether the mind and body differ not only in degree and nature but also in kind? The arrival of neuroscience with its several scientific experiments has radically challenged the understanding of relationship between mind and body and forced us to rethink our positions about it. Thus, there is a renewed vigour in studying about consciousness in modern times and it has thrown open several other ways of settling th is issue. This chapter will briefly discuss on how different philosophers perceived the relationship between mind and body in a person and critically analyse various theories of dualism and physicalism in detail and present their difficulties. The concluding part of the chapter will show the need to go beyond dualism and physicalism with the help of neuroscience. We begin our discussion with mind-body relationship in a person. 1.1 Mind-Body Relationship in a Person For many centuries, we have been trying to understand the mind-body relationship in a person. The difficulty behind explaining the relationship between mind-body in a person is that s/he is a dynamic entity.  [1]  Thus, one is in a continued mode of knowing oneself. There are several thinkers who hold the view that a person is composed of body and mind. At the same time there are also some thinkers who oppose this idea. Now we shall discuss the views of some philosophers. There are several ancient philosophers like Plato and Aristotle who expressed their views on mind-body relationship in a person. For Plato, human being is composed of body and soul. Body is nothing but a prison house into which his/her soul has been locked. His understanding of person is different from our understanding of human being.  [2]  For Plato, person belongs to intelligible world and human being belongs to sensible world. Secondly person can be transformed whereas human being cannot be because human being belongs to physical level of being.  [3]  Thus he says that a person, the subject of interest, is not a human being but rather a soul, an entity distinct from that of human being.  [4]  Here we can see a clear-cut distinction of soul and body in Platos thinking. Aristotle, on the contrary, saw the mind-body relationship from a completely different angle. He says that a person is a composite not of body and soul but of prime matter and the human soul which as a substantial form.  [5]  He does not perceive the distinction between mind and body; instead he makes the distinction between matter and form. Therefore, Aristotle understands body and soul as not of two complete beings in conflict with each other but complimenting each other because matter and form are inseparable in a primary substance. There are also modern philosophers like Hegel, Immanuel Kant and John Locke who understand the mind-body relationship quite differently. For Hegel, an individual is part of the larger life of the Mind. He says that, Mind or spirit, passes through dialectical stages of evolution, revealing itself as subjective mind, objective mind and absolute mind. The subjective mind expresses itself as soul, consciousness and spirit.  [6]  From the above statements it is very clear that he gives importance to mind alone. He has absorbed totally the body into mind; for he says, It (mind) embodies itself, creates a body for itself, and becomes a particular, individual soul.  [7]  Therefore what truly exists for him is mind and not body. However Immanuel Kant speaks about metaphysical dualism rather than substance dualism of the person. He sees person as a Transcendental Self because there is a level of self-awareness that is over and above the categories of normal philosophies. Human being is alone a rational being who has a will and a free choice of action. So Kant postulates person as a transcendental free being, an idea that the inner self is not bound by the laws of nature.  [8]  However, John Locke, being a modern philosopher understands human person as that of ancient philosophers. For him mind is the real person and body is only a possession.  [9]  He separates mind from body and shows that body is only a material reality. He says that, Every man has a property in his own person.   This no Body has any Right to but himself.  [10]  For him mind is the real person and in the real person the body aspect is integrated totally into it.  [11]   The philosophers have changed their focus in the recent years. They give more stress on the purpose of human life. They ask; what does it mean to be a human person? However, with the growing interest in neuroscience, the ontological question bounced back with new a quest. One of the forerunners and pioneers of this movement is Philip Clayton who brought back the same question with a new focus. Now we shall discus the extreme positions of mind-body relationship and their solutions. 1.2 Extreme Positions The Mind-Body relationship has been an unsettled question both for science and philosophy. It has been a herculean task for both scientists and philosophers, who were greatly involved in unlocking the issue of the relationship between mind and body. There are two sets of opposing ideologies proposed; namely dualism and physicalism. Most of the philosophers are divided on their opinions hence this issue seeks our utmost attentions. Here we shall examine these two positions in detail and see why we need to go beyond these divisions. As part of this session, 1.3 deals with substance dualism and property dualism and 1.4 tries to examine the critical appraisal of the mind body relationship. The second part begins in 1.5 which deals with physicalism. Let us begin with dualism. 1.3 Dualism Dualism simply means a condition of being double. It comes from the Latin word duo meaning two which denotes a state of two parts.  [12]  It was originally coined to highlight the co-eternal binary position; for example good and evil, body and mind, mental and material, dark and light etc. It is supported by several arguments.  [13]  In philosophy it is a world view that the world consists of or is explicable as two fundamental entities, such as body and mind, the condition of being double or duality.  [14]  From the point of theology, it speaks about that human being having two basic natures, the physical and spiritual. There are two kinds of dualism- substance dualism and property dualism. 1.3.1 Substance Dualism The substance dualism sees mind and body as two distinct and separate substances.  [15]  Several philosophers like Plato, Thomas Aquinas and Renà © Descartes too held a similar view. They see mind as something that is diametrically opposing body. The attribute of body is extension but at the same time they see that the body is passive; whereas the mind is thinking, active and free. The two substances are absolutely distinct and mind is without extension. Those who hold dualism say that they have a clear and distinct idea of themselves in so far as they are only a thinking and un-extended thing.  [16]  The distinction between body as material and mind as immaterial substance becomes a crucial point of discussion in substance dualism because they differ not only in kind but also in nature and degree. However it is a compelling concept because it gives us a hope of personal survival after death and also many religions hold this theory very dear to them.  [17]  We can see th is distinction in Indian philosophy too. The Sankhaya philosophy holds that there are two entities; namely Purusha  [18]  and Prakrti  [19]  which are the two constitutive elements of the world. However dualism is more clearly and intelligibly spelled by the western thinkers. Now we shall discuss briefly about two predominant philosophers: Plato, from the ancient schools and Renà © Descartes, from the modern thinkers, who represent the rest of the dualistic thinkers of their time. 1.3.1.1 Platonic Dualism Platonic Dualism can be seen very clear in Phaedo, one of his dialogues. In the dialogue, Plato accepts the two ultimate principles; namely body and mind. Here his dualism is metaphysical in nature because he deals with immortality of mind or soul.  [20]  He calls mind as soul.  [21]  For him, the mind is immortal and body is mortal.  [22]  The mind is the one which differentiates the living from the dead. He sees the body as a prison in which the soul is confined. In the imprisoned life, the mind is compelled to investigate the truth by means of the organs of perception of the body. Forms are universals and represent the essences of sensible particulars. Plato says that we do not see reality as a whole. We perceive equal things, but not equality itself. We perceive beautiful things but not beauty itself. To have insights into the pure essences of things, the mind must struggle to disassociate itself from the body as far as possible and turn its attention towards the cont emplation of not only to intelligible things but also to invisible things. Plato defines death as the separation of soul and body, and the state of being dead as state in which soul and body exist separately from one another.  [23]  Thus for Plato, the dualism of mind and body are opposite in nature. He establishes the distinction of mind and body by establishing the distinction between the immortality of mind and mortality of body. He proves the immortality of soul through Argument from Opposites, Argument from Recollection and the Argument from Affinity.  [24]  These three arguments are keys to establish his dualism. Plato defends his immortality of soul from the Argument from Opposites. He says that things that have an opposite come to be from their opposite. For example, if something comes to be taller, it must come to be taller from having been shorter; if something comes to be heavier, it must come to be so by first having been lighter. These processes can go in either direction. Similarly he says that dying comes from living, living must come from dying. Thus, we must come to life again after we die. During the interim between death and rebirth the soul exists apart from the body and has the opportunity to glimpse the Forms unmingled with matter in their pure and undiluted fullness. Thus the cycle of life goes on. The second defence for his immortality of soul is the Argument from Recollection. For Plato, soul must exist prior to birth because we can recollect things that could not have been learned in this life. According to Plato, we recognize unequal things and strive for equality. To notice inequality, we must comprehend what equality is. In order to know what equality is, we must have the prior knowledge so that we can understand the form of equality. Hence, the soul must have existed prior to birth to the form of equality.  [25]   The third defence for his immortality of soul is the Argument from Affinity. Plato claims that composite things are more liable to be destroyed than things that are simple. The forms  [26]  are true unities and therefore least likely ever to be annihilated. Further Plato says that invisible things such as forms are not apt to be disintegrated, whereas visible things are susceptible to decay and corruption. Since the body is visible and composite, it is subjected to decomposition. As against to body, the soul is invisible part of forms and purifies itself by having no more association with the body than necessary. Since the invisible things are the durable things, the soul, being invisible, must outlast the body. Further, soul becomes form-like immortal and survives the death of the body.  [27]  Through these three arguments Plato proves the immortality of soul or mind whereby he makes the distinction between body and mind; thus he proves the dualism. However Platos arguments are highly challenged even by his own disciple Aristotle. Firstly, the Argument from Opposites applies only to things that have an opposite and, as Aristotle notes, substances have no contraries.  [28]  Further, even if life comes from what is itself not alive, it does not follow that the living human comes from the union of a dead (i.e. separated) soul and a body. The principle that everything comes to be from its opposite via a two-directional process cannot hold up to critical scrutiny. Secondly, one becomes older from having been younger, there is no corresponding reverse process leading the older to become younger. If aging is a uni-directional process, perhaps dying is as well. The Arguments from Recollection and Affinity, on the other hand, presuppose the existence of forms and are therefore no more secure than the forms themselves. Thus these criticisms show that we cannot simply take the prior existence of soul as it is true. Therefore Platos und erstanding is more of metaphysical and bit of vague because there are several unanswered questions like things which have two different natures interact. At the same time we acknowledge, he has brought certain clarity in understanding dualism with clear proofs. Now we shall discuss the dualism proposed by Descartes. 1.3.1.2 Cartesian Dualism. Renà © Descartes is one of the modern Philosophers who has extensively dealt with dualism. For Descartes, body and mind are distinct substances and the immaterial mind is somehow associated with the material body.  [29]  Substance dualism gets more predominance in Cartesian dualism.  [30]  He says substance dualism goes along with the view that the identity of a person over time is constituted by the identity overtime of this substance, and in versions of the doctrine that countenance life after death, it is survival of this substance, often called soul perhaps along with certain memory and psychological continuities, that constitutes the survival of the person.  [31]  The idea that there is a fundamental difference in kind between the mind and body can be spelled out in two broadly different ways.  [32]  Descartes held that minds and bodies are substances of distinct kind that, in the case of living human beings, happen to be intimately related.  [33]  The disti nction between the body and mind is: the body is spacial, public and has material qualities; and mind is non-spacial, private and has distinctively mental qualities. By spacial, he means that it occupies some space and time for its existence. It is public which means it is visible and we can experience it. When he says that the body has material qualities, he means that it has several qualities by which the substance expresses itself and reveals it to others and through which we come to know the things.  [34]  Firstly, in contrast to body, the mind occupies no space therefore it can be anywhere at any time. In short it is beyond space and time. Secondly it possesses mental qualities of life feeling, perceiving, experience joys and sorrows of life etc. Thirdly the mind is private because we cannot perceive it.  [35]  Descartes believes that the world is made up of substances. A substance is not a thing as we think like water or coal, or paint. For Descartes substance is an in dividual thing or an entity. He says that substances are different; they are complex. He gives importance to human being and his/her rationality. He claimed that, human rationality could not be a physical process.  [36]   The dualism of Descartes sounds good; however, there are certain conceptual difficulties and seemingly insurmountable problems. One of the crucial issues is the interaction of mind-body which is totally opposing each other in nature and kind. If minds are as distinct from material things as Descartes claims, it seems at least paradoxical: how can then the two sorts of substances interact. In this case property dualism seems to solve some of the problems which substance dualism cannot. 1.3.2 Property Dualism Property dualism maintains that mind is not only one kind of physical substance, having physical or behavioral-material-functional properties but also nonphysical behaviorally-materially-functionally in-eliminable and irreducible properties.  [37]  The advantage of property dualism over substance dualism is that it avoids the casual interaction problem because this theory has no need to countenance causal interaction between material and immaterial or spatial and non-spatial substance, since it admits only that there is only material substance.  [38]  It also need not appeal to Gods divine abilities in order to account for mind-body interaction or the objectivity of the perceived world. It has an edge over materialism that it provides for the intuitive distinction between body and mind by positing a difference in their properties, and especially in the metaphysical categories of their properties. Property dualism holds that without both properties, we cannot satisfactorily ex plain the psychological phenomena. The in-eliminable and irreducible properties are said to be essential to mind because they are responsible for experience, feeling, object directionality and intentionality of psychological states.  [39]  This property dualism could be understood in three ways; namely Theory of Attribute, Anomalous Monism and Non-reductive materialism. 1.3.2.1 Theory of Attribute The first way of understanding the property dualism is through Spinozas theory of attribute. Attributes are part of Spinozas metaphysics.  [40]  For Spinoza God is the only Substance since Gods essence involves existence. He says that, God exists and, moreover, only God can fulfill the conditions for substance, therefore there can be only one substance.  [41]  It is a mistake to assert that mind and body as substances because they are not fully self-subsistent, but are dependent modes or manifestations of God. For him, A true substance must be that which contains within itself, as part of its essence, the complete explanation of its nature and existence.  [42]  This God has infinite attributes. But human being can know only two attributes; they are namely thought and extension. By attribute what Spinoza understands is that the intellect perceives substance as constituting its essence. For him, the attribute of thought is attached to mind and extension to the body. He says that the object of idea constituting the human mind is the body which is certain mode of extension. He says that Therefore, the minds power of understanding extends only as far as that which this idea of the body contains within itself, or which follows there from. Now this idea of the body involves and expresses no other attributes of God than extension and thought.  [43]  This attribute enables us to understand and talk about an extended world and a thinking world in terms of which we understand bodies and minds. He partly invented this theory of attribute for the sake of solving an outstanding question raised by Descartes philosophy of mind. If the mind is, or belongs to, a separate substance from that of the body, then how does the body-mind interact? In order to avoid the problem, Spinoza considered that mind and body is one and the same thing under the attribute of extension and thought. Though the Cartesian notion of dualism was logical, it had constant problems. It coul d not substantially explain the relationship between substance constructed as individual and substance constructed as matter or stuff. But Spinozas explanation came very close to a satisfactory theory.  [44]   1.3.2.2 Anomalous Monism Anomalous monism is proposed by Donald Davidson, who is an American pragmatist. Anomalous monism is a philosophical thesis about the mind- body relationship. This theory has twofold divisions; namely mental and physical.  [45]  It states that mental events are identical with physical events. Events are causes in virtue of the properties that they instantiate, unless mental properties and physical properties are also identified, questions about the causal redundancy of the mental reappear at the level of properties.  [46]  But Davidson says that the mental events are anomalous, that is to say these mental events are not regulated by strict physical laws. Hence, he proposed an identity theory of mind without the reductive bridge laws associated with the type-identity theory. He understands the ontological nature of the relationship of mental events especially propositional attitudes with physical actions. Davidson accepts that there is ontology of events where events, which may seem to be opposed to objects or states of affairs, are the fundamental, irreducible entities of the mental and physical universe. He also believes that event-individuation must be done on the basis of causal powers. He further argues in favour of the individualization of events on the basis of spatio-temporal localization. According to this view, all events are caused by and cause other events and for him this is the defining characteristics of what an event is. The important aspect of Davidsons ontology of events for anomalous monism is that an event has an indefinite number of properties or aspects. He says that a very simple physical action like switching on a light has a large variety of mental events especially reasoning; for example recognizing the need of light, making a choice to switch on etc. For Davidson, a particular reason causes a particular action. Thus it explains that reasons are causes and actions are effects of the causal efficacy of the mental events.  [47]   However there are also people who are highly critical about it. One of the criticisms about the anomalous monism is whether mental events are ever causes of physical events in virtue of their mental properties. Gibb says that If the mental properties of a mental event do make a causal difference, then unless one admits systematic causal over determination, this is to violate the causal closure principle, for according to it an events physical properties are sufficient for the causal effects that event has within the physical domain.  [48]  It is otherwise the mental properties of an event make no causal difference to the physical effects that the event has, then mental properties have the status of epiphenomena. He observes that Consequently, to identify mental events with physical events whilst distinguishing mental properties from physical properties are not to remove but merely to relocate the problem of mental causation.  [49]  For this reason, the non-reductive physicali st who identifies token mental events with physical events but maintains a property dualism can plausibly be accused of property epiphenomenalism. Secondly a strict law cannot be formulated in the same terms as the causal claim because causally related events must have descriptions under which they instantiate a strict law. Similarly, the causal claim and the relevant covering law cannot be formulated in purely mental terms because any mental event that causes a physical event must be characterizable in physical terms and therefore be physical. Hence, mental events are physical events. On the other hand, as there are no strict psychophysical laws that would support the reduction of mental concepts to physical concepts, anomalous monism leads to the rejection of any conceptual reduction.  [50]   1.3.2.3 Non-reductive Materialism Non-reductive materialism represents the current orthodoxy in Western Philosophy thinking about the ontological status of the mind. The proponents of non-reductive materialism hold that the mental is ontologically part of the material world; yet, mental properties are causally efficacious without being reducible to physical properties.  [51]  Even though the mind itself is really physical, our mentalist explanatory scheme is not reducible to physics but is instead autonomous. They hold both irreducibility of the mind as well physical nature of the mind as realism. They are also arguing that they are fundamentally unstable combination. The non-reductionist distinguishes mental kinds from physical kinds, where the mental includes sensation and thought, and the physical is roughly the domain of the physical sciences, including neurophysiology. But those who oppose it say that the whole question of explanatory autonomy became a topical philosophical issue which threatened the reducti onism because there was a general acceptance of materialist theories. It was broadly a metaphysical doctrine. It would seem to follow that all phenomena are susceptible to physical explanation, and if this is true then what can the ontological status be of those concepts, categories and theories which fall outside the domain of the physical sciences?  [52]  Then the non-reductive materialist may have to give up all pretense of having a realist view of mental terms, giving up all talk of real but non-physical mental properties. It seems that you cannot combine Physicalism with realism about the mental and at the same time hold out for the autonomy of the mental. However non-reductive materialism could be still seen as fundamentally a stable position. 1.4 An Appraisal of Mind-Body Relations Though Descartes argues for the mind-body dualism,  [53]  the sort of dualism for which he argues, entails certain conceptual difficulties and seemingly insuperable problems. The main difficulty with mental activity is that, as Descartes understands them, how do the mind and matter interact. If minds are as distinct from material things as Descartes claims, it seems at least paradoxical that the two sorts of substances should interact. The question of the relation between the mental and the physical can be posed equivalently as about mental and ph