Marijuana

The use of marijuana in human civilization dates back to 6000 B. C. In this era, China found that cannabis seeds are edible and later discovered a greater use as textiles. From that time period, humanity has made significant advancement, and has discovered further uses for the marijuana plant. Today, marijuana can be used as medical cannabis to treat ailments that other medication cannot possibly treat. Although medical cannabis has some great benefits, in the many countries it is still illegal to possess and/or use.Thus the legalization of marijuana should be legalized through its promising and beneficial results. Contrary to belief, medical cannabis has very few health risks compared to propaganda suggested to most people in mainstream media. Throughout the years many random and bogus facts of marijuana have circulated, many of these disputes however, have been debunk through actual scientific study done today. The monkey marijuana experiment in 1973 for example was a huge hoax. In the case study, the monkeys were exposed to marijuana smoke everyday and died after ninety days.The autopsy report ruled that hey died to a dead brain through great loss in brain cells. Therefore, the conclusion of the study was that marijuana kills brain cells, but the experiment failed to report the monkeys were being suffocated for five minutes on a daily schedule for three months. The process of asphyxiation or suffocation causes lack of oxygen to the brain, which leads to death of brain cells. Soon after, many more theories have been tested and most of the so-called health risks were nothing more than hokum.Marijuana has fairly less harmful effects, unlike other legal drugs such as: alcohol, tobacco, cetaminophen, amphetamine, OxyContin, Xanax, sleeping pills, and many other legal drugs. Adversely, compared to other drugs and the drugs listed prior, marijuana has very few health risks. Since there are very few scientifically proven health risks, they are much more minimal in h armful effects than other recreational drugs. Alcohol and tobacco for instance, have higher risk in use than marijuana.The Center of Disease Control and Prevention states that: There are approximately 80,000 deaths attributable to excessive alcohol use each year in the United States. l This makes xcessive alcohol use the 3r d leading lifestyle-related cause of death for the nation. 2 Excessive alcohol use is responsible for 2. 3 million years of potential life lost (YPLL) annually, or an average of about 30 years of potential life lost for each death. l In 2006, there were more than 1. 2 million emergency room visits and 2. 7 million physician office visits due to excessive drinking. The economic costs of excessive alcohol consumption in 2006 were estimated at $223. 5 billion. 3 Compared to the average marijuana smokers, tobacco smokers frequently smoke more as stated in Mikaela Conleys ABC News article, â€Å"Among the study participants, the average pot smoker lit up two to three times per month. The average tobacco user smoked eight cigarettes per day. † Due to the greater amount of frequency in lighting a cigarette the average tobacco smoke causes much more air pollution as well as second hand smoke.In summation, the negative output of marijuana is miniscule compared to the negative output of most legal drugs/over the counter drugs. The medical uses of prescribed a mysterious herb as tea. This tea was marijuana and was used to treat, everything from pain relief to earache to childbirth. Doctors also warned against overuse of marijuana, believing that too much consumption caused impotence, blindness and â€Å"seeing devils. (Stack& Suddath)† Ever since then the uses of medical cannabis has varied from nausea to cancer and even to pain relief.According to â€Å"Disabled World†, Few herbs offer a wide variety of therapeutic applications like these: Relief of muscle spasms, relief of chronic pain reduction in interlobular pressure inside t he eye, suppression of nausea, weight loss – increase and restore etabolism, AIDS – Marijuana can reduce the nausea, loss of appetite, vomiting from the condition itself and the medications as well. Today, medical cannabis remains one of the most controversial social issues around the world.Although many people disagree with the drug, for one boy it proved valuable results. Jayden David of California suffers from a, â€Å"debilitating form of epilepsy, which causes him to experience frequent seizures – some lasting up to 90 minutes. (Fox40)† This only treatment for his epilepsy prior to medical marijuana was twenty types of medication hat he must take everyday in order to control his epilepsy. Once Jayden was on CDB (cannabidol), â€Å"Jayden's seizures are down approximately 80 percent. Jayden is functioning now,' David, of Modesto, Calif. told Fox 40. ‘The doctors told me Jayden would never walk or talk. ‘ (Fox40)† This is Just one of the stories of many lives that medical cannabis has managed to improve, including: cancer, chemotherapy, anorexia, bulimia, and many other ill patients. Due to its already besmirched image, the process in which obtaining medicinal marijuana has become such a hurdle that it is much harder to obtain than it should. Along with its beneficial results as medical cannabis, marijuana could have a substantially great impact on economy.With the drug being legal, less police force is needed to enforce the law, thus saving a substantial amount of taxpayer's money from the â€Å"get-go'. The Budgetary Implications of Marijuana Prohibition in the United States reveals that, â€Å"The report estimates that legalizing marijuana would save $7. 7 billion per year in government expenditure on enforcement of prohibition. $5. 3 billion of this savings would accrue to state and local governments, while $2. 4 billion ould accrue to the federal government. This is Just from deprivation of reduced polic e force, TBIMP states that, â€Å"50% of possession arrests are due solely to marijuana possession rather than being incidental to some other crime. † Declaring the arrest rate of 50% of all arrests are marijuana possession shows and reinforces the idea of how much the United States can save with reduced arrests and enforcements. In addition to the legalization of the drug, it could be taxed and distributed as a product worldwide for increase GDP in not only the United States, but also many other countries. However in the U. S. he estimated report says it would yield is, â€Å"$2. 4 billion annually if marijuana were taxed like all other goods and $6. 2 billion annually if marijuana were taxed at rates comparable to those on alcohol and tobacco. † Increase of new product in the market allows more economic growth worldwide. If the enormous revenue of legalization of marijuana is so great, it imposes the question of the legitimacy of illegalization of a drug in the first place, and to answer that question frankly it should! morality of it (which is the only answer to the question imposed prior to this entence).Most people against marijuana say that it is a drug and it is bad, but hold no other credible evidence of it truly being â€Å"bad†. In 1920 the United States imposed an alcohol prohibition because of their morale of it being â€Å"bad†. Just like marijuana alcohol is a drug, and has many pros and cons, such as medical uses like a disinfectant as well as a recreational drug. The hypocrisy came when the government imposed the prohibition when the motto has been â€Å"for the people by the people†. This lack of representation of the people caused one of the greatest failures in law reation since slavery.Not only did prohibition fail in stopping people from drinking alcohol, it also increased the amount of people drinking as well as crime rate. The distillation process of making alcohol became a homemade Job, but due to the lack of proper equipment and sanitation this beverage was much more hazardous to drink. It was estimated at least ten thousand people died during the enforcement of the 1920 to 1933 Prohibition. During this time the profit of making alcohol skyrocketed, which made it more tempting to break the law.Along with the increase crime rate, it as also reported that vandalism and public disturbances increased. This example is currently like the prohibition of marijuana, not only is it making crime more profitable, but it is also increasing the negligence of the people consuming and the law enforcement. However, due to a greater understanding of responsibility and information of recreational drugs, modern day society has allowed awareness in safety of alcohol consumption. This awareness could also be used for marijuana, Just as it has been done for tobacco and other drugs.In summation, the use of marijuana medically and recreationally has been around ince the beginning of civilization, and sh ould still be continued today; Just as Bert Lance once said, â€Å"If it ain't broke, don't fix it. † In addition, the legalization of marijuana should Just be reinstated prior to it's ban through its promising medical uses for all sick and ill patients, its beneficial economic results for everybody, and its use as a reminder that public opinion are still held accountable; even with the modern political Jargon going around today.So, for the sake of the ill who needs the drugs, to us, the people who could benefit from the drug, we should keep in mind that the ecision is more than Just a basis of morality, but also the basis of something for all. â€Å"The needs of the many outweigh the needs of the one. Marijuana Even the Persian founder of Suffix, who struggled with depression until discovering the plant, requested in his death, ‘to be buried amid cannabis leaves so his spirit may walk in the shade Of the plant that eve him much joy in his lifetime† (Medical-Marijuana-Mentor. Com). However, if marijuana has been embraced by diverse faiths and civilizations, why is marijuana such a controversial subject now? In America's inception marijuana was used to generate vast government money by our founding fathers; George Washington and Thomas Jefferson both grew hemp on Mount Vernon.But in 1932, the Confirm State Narcotic Act gave legislative control of marijuana from the federal government to the states, thus prohibiting the use of marijuana (The Free Dictionary). Nevertheless, numerous studies have shown the benefits of marijuana outweigh its negative effects. Therefore, the stigma should be lifted so that the people of the Lignite States can enjoy the benefits of marijuana. The legali zation of marijuana in the U. S. Would lower crime, stimulate the economy, and provide medical relief.First of all, the legalization of marijuana would lower the crime rate in the United States by creating a safe environment for its users. If marijuana is taken off the street, and out of the hands of the dealers, the crimes associated with these types of dealings would also be taken off the street. It would put marijuana into a legal market where it could be controlled by the proper authorities. â€Å"By providing legal supplies of currently illegal drugs the price will fall, leading to a collapse in the illegal drug industry, and a reduction in crimes committed by both drug suppliers and users† (Legalization of Marijuana).To illustrate this, just three months after the state of Colorado legalized marijuana, crime decreased 14. 6% and in Denver from the same time last year†¦ Violent crime also went down 2. 4% (Natural Society). Another disconcerting problem with marijuan a being sold on the street is its accessibility to minors. Drug dealers do not discriminate and do not care whether the buyer is a minor or not; their interest is solely in their own profits. High school students have reported that illegal drugs are easier to access than alcohol and tobacco.This would obviously explain why the percentage of teens using weed is drastically on the rise. On the other hand, if marijuana was legalized and sold as cigarettes, the buyer or consumer would have to produce a valid identification before purchasing it, and a vendor cannot legally sell alcohol and tobacco to minors. As a result, legalizing Arizona would establish more of control of its distribution, and would also reduce the usage of it among minors. With the economy in the United States in shambles, legalizing marijuana would allow it to be a taxable item and would produce millions of dollars into the system. The new measure is expected to bring†¦ [in] $550 million combined, with more than 300 economists previously estimating that legalizing pot could save the U. S. Up to $14 billion a year† (Huff Post Business). We should not allow drug dealers the ability to control the market and benefit on a product that has the potential to ring in high profits into our much-needed empty confers. With marijuana being sold on the black market drug dealers charge exuberant prices because they have the monopoly on the market; keeping pot illegal is inadvertently enriching greedy drug dealers.On a similar note, by legalizing marijuana the demand will rise for more farms and dispensaries. With this comes more jobs because establishments like this would be hiring farmers, growers, and employees would be needed to run the new dispensaries, thus creating a new and large job market. By legalizing Marijuana it can be something the American people can profit from as a whole, as well as the U . S. Government, instead of a small group of criminals who's only priority is to enrich thems elves. Lastly, and most importantly marijuana can treat diverse mental and physical illnesses.Medical marijuana or cannabis has already been legalized in 20 of the 52 states in the U. S. Marijuana can treat cancer patients suffering from the affects of chemo and radiation by dehydrogenation's (TECH) -? which has pain-relieving properties. It can also be used to prevent the spread of cancer cells. â€Å"CB (one of the components n cannabis) represents the first nontoxic exogenous agent that can significantly decrease old-l expression in metastasis breast cancer cells leading to the down-regulation of tumor aggressiveness† (National Library of Medicine).Furthermore, marijuana can be used to treat and prevent eye disease such as glaucoma. It has also been know to treat mental illnesses such as depression and anxiety. In addition, some independent studies have shown Marijuana to prevent suicide in those who use it for medical purposes. Marijuana is, at present, successfully treat ing people suffering from the effects of illnesses, but only in the states that have legalized it. However, everyone should have access to the medicinal properties found in cannabis and the ability to use them legally.Therefore it should be legally available to those whose health can benefit from it. In closing, it is safe to say there are many beneficial uses to this controversial drug known as marijuana. Prohibiting the use of marijuana does not prevent it from being used, but rather gives a small and dangerous group a large portion of control and power. If we are to learn anything from the history of prohibition in the hearties in relation to alcohol is that it did the opposite of what it was intended, â€Å"Alcohol became more dangerous to consume; organized crime blossomed; courts and prisons systems became overloaded† (1 920-30. Mom). Such is the case of the country today in regards to marijuana. The legalization of marijuana would not raise but rather lower crime, and would allow marijuana to be more controlled by the governing authorities. It would produce billions of dollars into an economy frocked with debt and create jobs in a time where unemployment is at record highs. It would allow those offering from the horrors of illnesses to find a means to ease their pain, and in some cases actually treat the illness itself.

Impact of Leather Waste

1. 1. 1. Leather industrial waste: Prominent effectiveness of leather industry is amplified by high input and expenditure but on other side it causes huge waste of resource, incredible environmental pollution and biological chain destruction [17]. Streams of gaseous, liquid and solid waste are resulted by environmental blow of tanneries. Global leather industry generates 4 million tones of solid waste per year [18]. People use products of the leather-processing industry on a daily basis. These include especially shoes, leather and textile goods; we normally encounter leather products even in both public and private transport. The primary raw material for final products is hide from animals from slaughter houses and hide from game—i. e. waste from the meat industry, which is processed in tanneries and turned into leather. Therefore, the tanning industry can be considered one of the first industries to use and recycle secondary raw materials. Although the tanning industry is environmentally important as a principal user of meat industry waste, the industry is perceived as a consumer of resources and a producer of pollutants. Processing one metric ton of raw hide generates 200 kg of final leather product (containing 3 kg of chromium), 250 kg of non-tanned solid waste, 200 kg of tanned waste (containing 3 kg of chromium), and 50,000 kg of wastewater (containing 5 kg of chromium) [1]. Thus, only 20% of the raw material is converted into leather, and more than 60% of the chromium is in the solid and liquid waste. During the production of leather goods, especially shoes, manipulation waste is produced, whichmakes about 15–20% of the entry material—leather. The last kinds ofwaste are used leather products which have lost their utility value. 1. 1. The possibility of oxidation of CrIII to CrVI The basic question is the possible oxidation reaction from chromium III to chromium VI. In basic solutions, the oxidation of CrIII to CrVI by oxidants such as peroxides and hypohalide occurs with ease [2]. Such strong oxidation conditions are realized in the process of the sterilization of drinking water. This is the first threat to human health and life. Rain (especially acid rain) can leach chromium III from waste dumps, and soluble salts can then reach sources of drinking water. During the sterilization process by ozone or hypochloride, chromium III is converted into chromium VI and reacts with magnesium and calcium ions occurring in drinking water to produce carcinogenic magnesium and calcium chromate or dichromate salts. Another problem concerns the possibility of oxidation of CrIII into CrVI in gentle conditions by air in the wide range of pH. Principally, oxidation can be realized after the following equations: According to the European Commission (EC) the quantities of solid waste produced by tanneries depend on the type of leather processed, the source of hides and skins, and the techniques applied [2]. On an average, at the end of the process, about 20% of the weight of the raw hides is (grain side) leather [2]. On the other hand, in Rio Grande do Sul, approximately 40% of the initial raw material is transformed into solid and liquid wastes [3]. In the tanning industry, raw skin is transformed into leather by means of a series of chemical and mechanical operations [4,5]. Chromium salts (in particular, chromium sulfate) are the most widely used tanning substances today. Hides that have been tanned with chromium salts have a good mechanical resistance, an extraordinary dyeing suitability and a better hydrothermal resistance in comparison with hides treated with plant substances. Chromium salts also have a high rate of penetration into the inter fibrillar spaces of the skin, what represents a saving in terms of production time and a better control of the process [6]. In Brazil, approximately 90% of the leather industry uses chromium in hide processing, resulting in hazardous The conventional tannery methods lead to discharge of solutions with chromium concentrations in the range of 1500–4000 mg/l. The specification for the discharge of chromium containing liquid wastes stipulates a range of 0. 3–2 mg/l [21]. The tanning treatments to produce the wet blue leather yield sludge containing approximately 3% (w/w) of chromium [9]. The method commonly used for this waste disposal presents high operational costs. The production of chromium containing leather wastes (including chrome shavings and tanned splits) in leather industry has been recognized as a real problem for many years [ref]. The chromium leather wastes are generated principally during mechanical treatments carried out after tanning process. In this latter, chromium is bound with the collagen matrix, by cross linking with collagen carboxylic groups through coordinate covalent linkage [6–10]. The final chemical structure of the waste illustrated in Eq. (1), is obtained through two chemical phenomena â€Å"olation and oxolation†. As reported by numerous authors [6–12], the olation phenomenon is observed gradually with the increase of the alkalinity of the tanning medium. The olified complex continues its evolution through time and an acid discharge takes place while the oxygen-chrome coordinate links are transformed into covalent links (oxolation bridges) Eq. The great stability of the collagen–chromium complex produced makes the waste a non-biodegradable and toxic material, due to the chromium and nitrogen content about 4. 3% and 14%, respectively [13,14]. A large amount of waste still goes into land disposal [15]. Incineration in air atmosphere generates other forms of residual pollutant (gaseous emission and ashes) more noxious [16–21] The solid wastes generated _presented in Table 1. from leather industry can be broadly classified as untanned collagenous, tanned collagenous and non-proteinous wastes. Among the tanned collagenous waste, the one resulting from the finishing operation called buffing dust draws the most attention from the public and pollution control authorities. Buffing dust appears in a considerable proportion with processing of raw hides skins _i. e. 2–6 kg per ton of raw hides skins.. Buffing dust is a micro fined solid particulate impregnated with chromium, synthetic fat, oil, tanning agents and dye chemicals. Buffing dust carries about 2. 7% chromium on dry weight basis. This is carcinogenic in nature and it causes clinical problems like respiratory tract ailments w1x, allergic dermatitis, ulcers, perforated nasal septum, kidney malfunctions w2x and lung cancer w3x in humans exposed to the environment containing buffing dust particulates. Hence, it is cautioned by pollution control authorities to collect the buffing dust for safety disposal. The current practice of disposing of buffing dust consists of: _i. incineration in incinerators, _ii. land co-disposal w4–12x. Incineration causes serious air pollution problems because of release of toxic So and No gases w13x, and it has been observed x x that at 8008C, about 40% of Cr_III. is converted into Cr_VI. during the incineration of Cr laden solid waste w14x. The tanning industry is familiar with its being a potentially pollution-intensive industry. The nvironmental impacts from tanneries result from liquid, solid and gaseous waste streams. It must be emphasized that 4million tones of solid waste per year is generated by the global tannery industry [6]. According to the estimation of Sreeram et al. , about 0. 8 million tons of chromium tanned shavings are generated per year globally [7]. The solid wastes from tannery industries may have significant Cr (III) conten t. Even though Cr (III) is viewed as not toxic, possible oxidation of Cr(III) to Cr(VI), due to the acid rains or incineration, threats the environment since Cr(VI) is a more toxic species. Therefore, the conventional disposal methods, land-filling and incineration, cannot be considered a solution to the disposal problem of tanned leather wastes in eco-friendly manner. In literature, there are many studies on the treatment of tanned leather wastes mainly including the extraction of chromium from wastes to re-use in the tanning process [8,9] and isolation of protein fractions [10,11]. The tanning industry generates a huge quantum of liquid and solid wastes while producing finished leather. Tanning is the main process followed in leather manufacturing that protects the leather against some environmental effects such as microbial degradation, heat, sweat or moisture, etc [1]. In tanning industry raw skins/hides are transformed into leather by means of a series of chemical and mechanical operations [2,3]. The tanning process is usually accomplished in three distinct phases, i. e. , preparation of the raw live stock to tan with tanning agents, tanning with mineral/vegetable tanning agents and post tanning to impart colour to finished leather. Basic chromium sulfate is the most widely used tanning agent for converting putrescible collagen fibres into non-putrescible leather matrix. Chrome tanned leathers have improved mechanical resistance, extraordinary dyeing suitability and better hydrothermal resistance in comparison with vegetable tanned leather. The solid wastes generated from leather industry can be broadly classified into untanned collagenous, tanned collagenous and non-proteinaceous wastes. Among the tanned collagenous waste, the one resulting from the finishing operation is called chrome buffing dust (CBD). CBD is a micro fined solid particulate impregnated with chromium, synthetic fat, oil, tanning agents and dye chemicals. About 2–6 kg of CBD is generated as a solid waste per ton of skin/hide processed. CBD contains chromium, it is carcinogenic in nature and it causes clinical problems like respiratory tract ailments, ulcers, perforated nasal septum, kidney malfunction [4] and lung cancer [5] in humans exposed to the environment containing buffing dust particulates. Hence, it is advised by pollution control authorities to collect the CBD for safe disposal. The current methods for disposing buffing dust are land codisposal and thermal incineration. Land co-disposal method is not preferred for the reasons such as overall high pollution emissions and low energy recovery. The leather industry generates a large amount of a Cr-containing solid waste (wet blue leather), with approximately 3% (w/w) of chromium. However, the leather industry has commonly been associated with high pollution due to the bad smell, organic wastes and high water consumption caused during traditional manufacturing processes [2]. Different forms of waste in quality and quantity, which emerge during the transformation of hides and skins into leathers in thousands of leather factories, from primitive to modern all around the world, have negative impacts on the environment. According to the data received from the studies of several researchers, approximately 200 kg of leather is manufactured from 1 tone of wet-salted hide [1-3]. This amount constitutes about 20% of rawhide weight. More than 600 kg of solid waste is generated during the transformation of Raw hide into leather. That is to say, solid wastes containing protein and fat that constitute more than 60% of rawhide weight are disposed to the environment by leather factories without turning them to good use In other words, besides the 30-35m3 waste water disposed to environment during the processing of every 1 ton of rawhide in world leather industry, the data from FAO reveals that approximately 8. 5 million tons of solid waste is generated during the production of 11 million tons of raw hide processed in the world [4]. Solid wastes generated by the leather industry in these stages of processes may be classified as follows: i. astes from untanned hides/skins (trimmings, fleshing wastes) ii. wastes from tanned leather (shaving wastes, buffing dust) iii. wastes from dyed and finished leather (trimmings from leather) Data obtained from research reveals that 80% of solid wastes are generated during pre-tanning processes, while 20% of the wastes are caused by post-tanning processes Due to the bad smell th ey produce during their putrefaction and their harmful chemical content, untanned hide/skin wastes have negative effects on the soil and/or water resources of the environment where they are discharged, in other words n the local plant flora and animal fauna. Therefore, uncontrolled discharge of such wastes should be prevented without taking adequate precautions. Legal arrangements gradually gaining speed all over the world enforce the leather industry to apply innovations in terms of reusing solid wastes generated during leather production processes such as fleshing, shaving, trimming and splits. Solid wastes create a major problem for leather industry in terms of both their variety and quantity. A high amount of reusable waste is generated in the leather industry. It is possible to recycle these products and even use them as raw materials for different industries [7]. The variety and quantity of solid wastes depends on animal species, breeding conditions, slaughterhouse practices, conservation conditions, leather process stages, mechanical operations, qualification of the personnel, and chemicals used in processes. Yet this fact causes uncertainties in reusing the generated wastes.

Polymer Concrete

POLYMER COCNCRETE 1. Introduction Despite being thought of as a modern material, concrete has been in use for hundreds of years. The word concrete comes from the Latin concretus, which means â€Å"mixed together† or compounded. Concrete is an extremely popular structural material due to its low cost and easy fabrication. Concrete is made up of sand or stone, known as aggregate, combined with cement paste to bind it. Aggregate can be of various sizes. It is broadly categorized as fine (commonly sand) and coarse (typically crushed stone or gravel).The greater proportion of concrete is aggregate which is bulky and relatively cheaper than the cement. As much of the constituents of concrete come from stone, it is often thought that concrete has the same qualities and will last forever. Concrete has been called artificial stone, cast stone, reconstructed stone and reconstituted stone. However, concrete must be thought of as a distinct material to stone. It has its own characteristic s in terms of durability, weathering and repair. Concrete is a relatively durable and robust building material, but it can be severely weakened by poor manufacture or a very aggressive environment.A number of historic concrete structures exhibit problems that are related to their date of origin. It is referred that the concrete is porous. The porosity is due to air-voids, water voids or due to the inherent porosity of gel structure itself. On account of the porosity, the strength of concrete is naturally reduced. It is conceived by many research workers that reduction of porosity results in increase of strength of concrete. Therefore, process like vibration, pressure application spinning etc. , have been practiced mainly to reduce porosity.All these methods have been found to be helpful to a great extent, but none of these methods could really help to reduce the water voids and the inherent porosity of gel which is estimated to be about 28%. The impregnation of monomer and subsequen t polymerization is the latest technique adopted to reduce the inherent porosity of the concrete to improve the strength and other properties of concrete. These problems can be solved by application of polymer in concrete construction. A polymer is a large molecule containing hundreds or thousands of atoms formed by combining one, two or occasionally more kinds of small molecule (monomers) into chain r network structures. The main polymer material used in concrete construction are polymer modified concrete and polymer concrete. Polymer modified concrete may be divided into two classes: polymer impregnated concrete and polymer cement concrete. The first is produced by impregnation of pre-cast hardened Portland cement concrete with a monomer that is subsequently converted to solid polymer. To produce the second, part of the cement binder of the concrete mix is replaced by polymer (often in latex form).Both have higher strength, lower water permeability, better resistance to chemicals, and greater freeze-thaw stability than conventional concrete. Polymer concrete (PC), or resin concrete, consists of a polymer binder which may be a thermoplastic but more frequently is a thermosetting polymer, and a mineral filler such as aggregate, gravel and crushed stone. PC has higher strength, greater resistance to chemicals and corrosive agents, lower water absorption and higher freeze-thaw stability than conventional Portland cement concrete.The pioneering work for the development of polymer concrete was taken up by United States Bureau of Reclamation (USBR). The initial exploratory works carried out at the Brookhaven National Laboratory (BNL) in cooperation with USBR and US in Atomic Energy Commission (AEC) revealed great improvement in compressive strength, permeability, impact resistance and abrasion resistance. The development of concrete-polymer composite material is directed at producing a new material by combining the ancient technology of cement concrete with the mod ern technology of polymer chemistry. 2.Types of Polymer Concrete Four types of polymer concrete materials are being developed presently. They are: a) Polymer Concrete (PC) b) Polymer Cement Concrete (PCC) c) Polymer impregnated Concrete (PIC) d) Partially Impregnated and surface coated polymer concrete The composites using polymer can be: polymer concrete (PC), when the binder is a polymer that replaces the cement paste, polymer modified concrete (PMC/ PCC), when the polymer is used near cement, polymer impregnated concrete (PIC), when the cement concrete is treated by soaking and polymerization.These composites have some advantages compared to ordinary cement concrete such as,rapid hardening, high mechanical strengths, chemical resistance, etc. Among the disadvantages is their high cost. The utilization domain of polymer concrete is continuously diversifying: PMC is widely used for floor and bridge overlays; acrylic latex has been used to produce mortars which can be sprayed on arc hitectural finish ; PIC was first widely used in bridge decks, pipes and conduits for aggressive fluids, floor tiles, building cladding, hazardous waste containment, post-tensioned beams and slabs, and stay-in place formwork.Polymer concrete is similar to ordinary cement concrete because it contains fine and coarse aggregates, but the hydraulic binder is totally substituted with a polymer material. The aggregates are bounded together by the polymer matrix. Polymer concrete contains no cement or water. The performances of polymeric concrete depend on the polymer properties, type of filler and aggregates, reinforcing fiber type, curing temperature, components dosage, etc. Polymer binder can be a thermoplastic, but more frequently a thermosetting polymer.The polymers most frequently used are based on four types of monomers or pre polymer system: methyl methacrylate, polyester prepolymerstyrene, epoxyde prepolymer hardener and furfuryl alcohol . The aggregates used in dry state can be s ilicates, quartz, crushed stone, gravel, limestone, calcareous, granite, clay, etc. In the composition can be used also the filler. Different types of fine materials can be used such as: fly ash, silica fume, phosphogyps, cinder, etc. Filler, especially fly ash, can improve the properties of polymer concrete . 3. History †¢ PC was used as early as 1958 in the USA to produce building cladding. Both PC and PCC have been in commercial use since the 1950s †¢ PIC was developed and has been in use since the 1970s †¢ Polymer concrete products have been used for decades in engineering construction like machine foundations, in the building industry for facade products and sanitary parts, in electrical engineering for isolation devices and especially in the chemical industry for all types of ducts due to its favourable properties, especially its corrosion resistance as well as its strength and elasticity †¢ The development of polymer concrete products, mostly pipe, dates b ack to the early 1960`s.The objective was to achieve a substantial increase in resistance to chemical attack †¢ With the development of trenchless technologies (micro-tunneling and pipe jacking) in 1970`s, polymer concrete pipes became popular in sewer systems.As such over the past years, the process of production and manufacturing of polymer concrete products like pipes, manholes and structures have been fundamentally improved †¢ Today it is used for cultured marble for counter tops, lavatories, as repair material, overlays for bridge and floors in sport arenas and stadiums, laboratories, hospitals, factories; also precast PC was used for drains, underground boxes, manholes, acid tanks and cells, tunnel lining, shells, floor tiles, architectural mouldings and machine tools and bases 4.Significance †¢ Depending on the materials employed, PC can develop compressive strengths of the order of 140 MPa within hours or even minutes and is therefore suitable for emergency co ncreting jobs in mines, tunnels, and highways †¢ PCC possess excellent bonding ability to old concrete, and high durability to aggressive solutions; it has therefore been used mainly for overlays in industrial floors, and for rehabilitation of deteriorated bridge decks. In the case of PIC, by effectively sealing the micro-cracks and capillary pores, it is possible to produce a virtually impermeable product which gives an ultimate strength of the same order as that of PC. PIC has been used for the production of high-strength pre-cast products and for improving the durability of bridge deck surfaces †¢ PCC possess excellent bonding ability to old concrete, and high durability to aggressive solutions; it has therefore been used mainly for overlays in industrial floors, and for rehabilitation of deteriorated bridge decks. In the case of PIC, by effectively sealing the micro-cracks and capillary pores, it is possible to produce a virtually impermeable product which gives an ult imate strength of the same order as that of PC. PIC has been used for the production of high-strength pre-cast products and for improving the durability of bridge deck surfaces †¢ Polymer concrete (PC) is a mixture of aggregates with a polymer as the sole binder. To minimize the amount of the expensive binder, it is very important to achieve the maximum possible dry packed density of the aggregate. . Polymer Concrete (PC) Polymer concrete is an aggregate bound with a polymer binder instead of Portland Cement as in conventional concrete. The main technique in producing PC is to minimize void volume in the aggregate mass so as to reduce the quantity of polymer needed for binding the aggregates. This is achieved by properly grading and mixing the aggregates to attain the maximum density and minimum void volume. The graded aggregates are prepacked and vibrated in a mould.Monomer is then diffused up through the aggregates and polymerization is initiated by radiation or chemical mean s. A silane coupling agent is added to the monomer to improve the bond strength between the polymer and the aggregate. In case polyester resins are used no polymerization is required. An important reason for the development of this material is the advantage it offers over conventional concrete where the alkaline Portland cement on curing, forms internal voids. Water can be entrapped in these voids which on freezing can readily cracks the concrete.Also the alkaline Portland cement is easily attacked by chemically aggressive materials which results in rapid deterioration, whereas polymers can be made compact with minimum voids and are hydrophobic and resistant to chemical attack. The strength obtained with PC can be as high as 140 MPa with a short curing period. However, such polymer concretes tend to be brittle and it is reported that dispersion of fiber reinforcement would improve the toughness and tensile strength of the material.The use of fibrous polyester concrete (FPC) in the c ompressive region of reinforced concrete beams provides a high strength, ductile concrete at reasonable cost. Also polyester concretes are visco-elastic in nature and will fail under sustained compressive loading at stress levels greater than 50 per cent of the ultimate strength. Therefore polyester concrete should be considered for structures with a high ratio of live load to dead load and for composite structures in which the polymer concrete may relax during long-term loading.Experiments conducted on FPC composite beams have indicated that they are performance effective when compared to reinforced concrete beam of equal steel reinforcement percentage. Such beams utilize steel in the region of high tensile stress, fibrous polyester concrete (FPC) with its favourable compressive behavior, in the regions of high compressive stress and Portland cement concrete in the regions of relatively low flexural stress. Properties of Polymer Concrete: †¢ Due to good chemical resistance and high initial strength and modulus of elasticity, industrial use of PC has been mainly in overlays and repair jobs. Thermal and creep characteristics of the material are usually not favorable for structural applications of PC. †¢ Polyester concretes are visco-elastic and will fail under a sustained compressive loading at stress levels greater than 50 percent of the ultimate strength. Sustained loadings at a stress level of 25 percent did not reduce ultimate strength capacity for a loading period of 1000 hr. 6. Polymer Cement Concrete (PCC) Polymer cement concrete is made by mixing cement, aggregates, water and monomer, such plastic mixture is cast in moulds.Cured, dried and polymerized. The monomers that are used in PCC are: a) Polyster-styrene. b) Epoxy-styrene c) Furans d) Vinylidene Chloride However, the results obtained by the production of PCC in this way have been disappointing and have shown relatively modest improvement of strength and durability. In many cases material s poorer than ordinary concrete are obtained. This behavior is explained by the fact that organic materials (monomers) are incompatible with aqueous systems and sometimes interfere with the alkaline cement hydration process.Recently Russian authors have reported the production of a superior Polymer cement concrete by the incorporation of furfural alcohol and aniline hydrochloride in the wet mix. This material is claimed to be specially dense and non-shrinking and to have high corrosion resistance, low permeability and high resistance to vibrations and axial extension. Washington State University in cooperation with Bureau of Reclamation tested the incorporation of several monomers into Wet Concrete for preparing PCC for fabrication of distillation units for water desalination plants.However, it is reported that only epoxy resin produced a concrete that showed some superior characteristics over ordinary concrete. †¢ The materials and the production technology for concrete in PCC are the same as those used in normal Portland Cement concrete except that latex, which is a colloidal suspension of polymer in water, is used as an admixture. †¢ Earlier latexes were based on polyvinyl acetate or polyvinylidene chloride, but these are seldom used now because of the risk of corrosion of steel in concrete in the latter case, and low wet strengths in the former. Elasto-meric or rubberlike polymers based on styrenebutadiene and polyacrylate copolymers are more commonly used now. Latex: †¢ A latex generally contains about 50 % by weight of spherical and very small (0. 01 to 1 m in diameter) polymer articles held in suspension in water by surface-active agents. †¢ The presence of surface-active agents in the latex tends to incorporate large amounts of entrained air in concrete; therefore, air detraining agents are usually added to commercial latexes. 10 to 25 percent polymer (solid basis) by weight of cement is used in typical PCC formulations †¢ The addition of latex provides a large quantity of the needed mixing water in concrete. †¢ The application of PCC is limited to overlays where durability to severe environmental conditions is of primary concern. †¢ PCC is made with as low an addition of extra mixing water as possible; the spherical polymer molecules and the entrained air associated with the latex usually provide excellent workability. Concrete Mix and Curing: †¢ Typically, water-cement ratios are in the range0. 40 to 0. 5, and cement contents are on the order of 390 to 420 kg/m3. †¢ The hardening of a latex takes place by drying or loss of water. †¢ Dry curing is mandatory for PCC; the material cured in air is believed to form a continuous and coherent polymer film which coats the cement hydration products, aggregate particles, and even the capillary pores. Properties: †¢ The most impressive characteristics of PCC are its ability to bond strongly with old concrete, and to resist the entry o f water and aggressive solutions. †¢ It is believed that the polymer film lining the capillary pores and micro-cracks does an excellent job in impeding the fluid flow in PCC. These characteristics have made the PCC a popular material for rehabilitation of deteriorated floors, pavements, and bridge decks. 7. Polymer Impregnated Concrete (PIC) Polymer impregnated concrete is one of the widely used polymer composite. It is nothing but a pre-cast conventional concrete, cured and dried in oven, or by dielectric heating from which the air in the open cell is removed by vacuum. Then a low viscosity monomer is diffused through the open cell and polymerized by using radiation, application of heat or by chemical initiation. Mainly the following types of monomer are used: a) Methylmethacrylate (MMA) ) Styrene c) Acrylonitrile d) T-butyl styrene e) Other thermoplastic monomers The amount of monomer that can be loaded into a concrete specimen is limited by the amount of water and air that h as occupied the total void space. It is necessary to know the concentration of water and air void in the system to determine the rate of monomer penetration. However, the main research effort has been towards obtaining a maximum monomer loading in concrete by the removal of water and air from the concrete by vacuum or thermal drying, the latter being more practicable for water removal because of its rapidity.Another parameter to consider is evacuation of the specimen prior to soaking in monomer. This eliminates the entrapment of air towards the centre of the specimen during soaking which might otherwise prevent total or maximum monomer loading. The application of pressure is another technique to reduce monomer loading time. 8. Partially Impregnated (or Coated in Depth CID) and Surface Coated (SC) Concrete Partial impregnation may be sufficient in situations where the major requirement is surface resistance against chemical and mechanical attack in addition to strength increase.Even with only partial impregnation, significant increase in the strength of original concrete has been obtained. The partially impregnated concrete could be produced by initially soaking the dried specimens in liquid monomer like methyl methacrylate, then sealing them by keeping them under hot water at 70 C to prevent or minimize loss due to evaporation. The polymerization can be done by using thermal catalytic method in which three per cent by weight of benzoyl peroxide is added to the monomer as a catalyst. It is seen that the depth of monomer penetration is dependent upon following: a) Pore structure of hardened and dried concrete ) The duration of soaking, and c) The viscosity of the monomer The potential application of polymer impregnated concrete surface treatment (surface coated concrete, SC) is in improving the durability of concrete bridge decks. Bridge deck deterioration is a serious problem everywhere, particularly due to an abrasive wear, freeze-thaw deterioration, spalling and corrosion of reinforcement. Excellent penetration has been achieved by ponding the monomer on the concrete surface. Due care should be taken to prevent evaporation of monomer when ponded on concrete surface.A 5 cms thick slab, on being soaked by MMA for 25 hours produced a polymer surface coated depth of 2. 5 cms. Significant increases in the tensile and compressive strengths, modulus of elasticity and resistance to acid attack have been achieved. The application of monomer for field application like in bridge decks poses more problems than laboratory application. A typical surface treatment in the field can be done in the following manner. a) The surface is dried for several days with electrical heating blanket. b) Remove the heating blanket and cover the slab with 0. 4 cum oven-dried light-weight aggregate per 100 sqm. c) Apply initially 2,000 to 3,000 ml of the monomer system per square meter. d) Cover the surface with polyethylene to retard evaporation. e) Shade the surface to prevent temperature increase which might initiate polymerization prematurely, that may reduce penetration into the concrete. f) Add periodically additional monomer to keep the aggregate moist for minimum soak time of 8 hours. g) Apply heat to polymerize the monometer: Heating blanket, steam or hot water can be used for this purpose. Some of the promising monomer systems for this purpose are: ) Methylmethacrystalate (MMA), 1% Benzoyl peroxide (BP), 10% Trimethylopropane thimethacrylate (TMPTMA). b) Isodecyl methacrystalate (IDMA), 1% BP, 10% TMPTMA c) Isobutylmethacrystalate (IBMA), 1% BP, 10% TMPTMA BP acts as a catalyst and TMPTMA is a cross linking agent which helps in polymerization at low temperature of 52%C. 9. Properties of Polymer Impregnated Concrete Since polymer impregnated concrete (PIC) is one of the most important category of polymer concrete, the properties of PIC are discussed below. Stress – Strain Relationship The stress strain curve for MMA –impreg nated concrete tested to failure is shown in fig. elow.. PIC has a nearly linear stress strain relationship to failure. There is very little departure from linearity upto 90% of ultimate strength and there is no abrupt change at the proportional limit. The stress strain curves for Styrene TMTMPTMA impregnated concrete also show the same characteristics as for MMA impregnated concrete. The modulus of elasticity increased from 27 GPa for un-impregnated specimen to 49 GPa for MMA impregnated specimens. [pic] Compressive Strength The effect of polymer loading on the compressive strength in PIC is given in the following figure.Using methylemethacrystalate as monomer and with a polymer loading of 6. 4%, strength of the order of 144 MPa have been obtained using radiation technique of polymerization. (The control specimen had compressive strength of 38 MPa). The compressive strength obtained with thermal catalytic process was 130 MPa. [pic] [pic] Styrene impregnated specimens exhibit simila r trends, except that the strength levels were somewhat lower. The polymerization by radiation method produced a concrete of higher strength than the produced by thermal catalytic method.Perlite concrete impregnated with MMA and polyester styrene have also shown considerable increases in compressive strengths. It is found the higher strengths are obtained with MMA impregnated sample than with polyester styrene. The average compressive strength for a 1:8 non-air entrained perlite concrete samples, impregnated with MMA was 56 MPa for polymer loading of 63% compared to control specimen of compressive strength 1. 2 MPa. Tensile Strength The increase in tensile strength in the case of PIC has been observed to be as high as 3. times that of the control specimen for polymer loading of 6. 4% MMA i. e. impregnated concrete have shown tensile strength of the order of 11. 6 MPa compared to the strength of control specimen of 3 MPa using radiation process of polymerization. Thermal catalyticall y initiated polymerization, produced concrete with tensile strength 3. 6 times that of the control specimen and 7. 3% less than that of radiation produced concrete. Polymer Concrete : Polyester resin concrete with binder continent varying from 20 to 25% have shown tensile strengths in the range of 9 to 10 MPa at 7 days.Polymer Cement Concrete: Polymer cement concrete using latex has given tensile strength of 5. 8 MPa with a latex / cement ratio of 0. 25; compared to the control specimen of 4. 4 MPa strength. The increase in tensile strength is very modest. Flexural Strength Polymer impregnated concrete with polymer loading of 5. 6% MMA and polymerized by radiation have shown flexural strength 3. 6 times more than that of the control specimen, i. e. the flexural strength was increased to 18. 8 MPa from 5. 2 MPa. Polymer Concrete (PC) Polymer resin concrete has been reported to give flexural strength of the order of 15 MPa at 7 days.Creep Compressive Creep deformation of MMA impregnat ed concrete and styrene-impregnated concrete has been observed to be in direction opposite to that of the applied road i. e, Negative Creep. After the typical initial movement during load application, these concretes expand under sustained compression. The reason for this negative creep in PIC is not very clear though it may be possible that it is due to residual stresses generated in the concrete after polymerization of monomers. The increased volume may also be due to phase changes induced by pressure. This behaviour has been noticed at a relatively loiw loading of 5. MPa. Otherwise creep deformation of PIC concrete is generally one-tenth of conventional concrete, when compared on a basis of deformation per unit load. Creep deformation generally stabilizes after two to three months. Shrinking due to Polymerisation Shrinkage occurs through two stages of impregnation treatment i. e. , through initial drying and through polymerisation. The shrinkage through polymerisation is peculiar to PIC and could be several times greater than the normal drying shrinkage. It has been seen that for the same base material, different monomer systems cause different amounts of shrinkage.It is expected that the shrinkage due to polymerisation will be less for a base that has higher modulus of elasticity. Durability The saturation of the hydrated cement with corrosion resistant polymer probably acts as a protective coating and results in excellent improvement in durability. a) Frees Thaw Resistance: Polymer impregnated concrete has shown excellent resistance to freeze-thaw MMA impregnated and radiation polymerized specimens have withstood 8110 cyclens of freeze-thaw compared to 740 cycles in case of unimpregnated concrete. Even partially impregnated concrete withstood 2310 cycles. ) Resistance to Sulphate Attack: Keeping a failure criteria of 0. 5% expansion, it has been observed that there is atleast 200 percent improvement in the resistance of polymer impregnated concrete and 89 % improvement in the case of partially impregnated concrete over the conventional concrete. c) Acid Resistance: The acid resistance of PIC has been observed to improve by 1200 percent when exposed to 15% HCI for 1395 days. Water Absorption A maximum reduction of 95 percent in water absorption has been observed with concrete containing 5. 9 percent polymer loading. Co-efficient of Thermal Expansion:Polymer impregnated concrete has higher co-efficient of thermal expansion compared to conventional concrete. Compared to the unimpregnated concrete having a value of 4. 02 X 10-6, a 5. 5% MMA, radiation polymerized concrete has a co-efficient of thermal expansion of 5. 63 X 10-6, and styrene impregnated specimens have shown a value of 5. 10 X 10-6. Resistance to Abrasion Polymer impregnated concrete has shown appreciable improvement in resistance to abrasion. A 5. 5% MMA impregnated concrete has been found to be 50 to 80 per cent more resistance to abrasion than the control specimen.Even s urface impregnated concrete slabs have shown an improvement of 20 to 50%. Wear and Skid Resistance. Though there may be apprehension that polymer filled voids in polymer concrete might produce a slippery surface, on actual wear track test, it was found that the treated surfaces show excellent skid resistance compared to the unimpregnated surfaces. The wear after 50,000 simlated vehicular passes has been less than 0. 025cm. Fracture of Polymer impregnated Concrete Polymer impregnation of concrete changes its microstructure radically resulting in a change in the cracking behaviour of the impregnated concrete under load.Impregnation improves the strength of the mortar matrix and also the strength of the paste-aggregate interface by elimination of microcracks. Polymer probably enters the aggregates also and forms a network of polymer fibres across the interface, thus strengthening it. Radiographic studies have shown that micro cracking starts first around 70 to 80% of the ultimate load, very often in the mortar phase. When an advancing crack reaches an aggregate, it does not follow the aggregate boundary as in ordinary concrete, but usually propagates through the aggregate.This indicates that the paste aggregate interface bond is significantly improved by polymer impregnation. It has been observed that PIC indicates nearly linear behaviour to failure, which is typical of brittle material. The brittle nature of PIC presents a severe design limitation. It would be ideal to produce a material with the slow failure mode of normal concrete while retaining the high strength and modulus of elasticity of PIC. One method to achieve this ideal is to adjust the past aggregate bond so that the failure mode is through the interface like in ordinary concrete.In principle, this can be achieved by using a very strong and tough aggregate, so that the advancing crack is diverted round to the paste-aggregate interface. The fracture mode of PIC can also be altered by incorporating a small quantity (1% by volume) of fibres in the matrix. The fibres do not affect the modulus of elasticity of concrete due to their low concentration, but serve to inhibit crack propagation through the mortar by acting as crack arrestors. 10. Sequence of Operations Drying and evacuation:The time and temperature needed for removal of free water from the capillary pores of moist-cured products depend on the thickness of the elements. At the drying temperatures ordinarily used (i. e. , 105 C), it may require 3 to 7 days before free water has been completely removed from a 150- by 300-mm concrete cylinder. Temperatures on the order of 150 C can accelerate the drying process so that it is complete in 1 to 2 days. Soaking the dried concrete in a monomer: The in situ penetration of concrete in the field may be achieved by surface ponding, but precast elements are directly immersed in the monomercatalyst mixture.Commercial monomers contain inhibitors that prevent premature polymerization dur ing storage; the catalyst serves to overcome the effect of the inhibitor. Sealing the monomer: To prevent loss of monomer by evaporation during handling and polymerization, the impregnated elements must be effectively sealed in steel containers or several layers of aluminum foil; In the rehabilitation of bridge decks this has been achieved by covering the surface with sand. Polymerizing the monomer: Thermal – catalytical polymerization is the preferred technique.The time for complete polymerization of the monomer in the sealed elements exposed to steam, hot water or air, or infrared heat at 70 to C may vary from a few to several hours. In the case of a MMA-benzoyl peroxide mixture, no differences in strength were found between specimens polymerized at C with hot air for 16 hr or with hot water for 4 hr. 11. Application of Polymer Impregnated Concrete Keeping in view the numerous beneficial properties of the PIC, it is found useful in a large number of applications, some of wh ich have been listed and discussed below: a) Pre-fabricated structural elements. ) Pre-stressed Concrete c) Marine works d) Desalination Plants e) Nuclear Power plants f) Sewage works-pipe and disposal works. g) Ferro cement products h) For water proofing of structures i) Industrial applications a) Pre-fabricated Structural Elements: For solving the tremendous problem of Urban Housing shortage, maintaining quality, economy and speed, builders had to fall back on pre-fabricated techniques of construction. At present due to the low strength of conventional concrete, the pre-fabricated sections are large and heavy, resulting in costly handling and erection.These reasons have prevented wide adoption of pre-fabrication in many countries. At present, the technique of polymer impregnation is ideally suited for pre cast concrete, it will find unquestionable use in industrialization of building components. Owning to higher strength, much thinner and lighter sections could be used which enabl es easy handling and erection. They can be even used in high rise building without much difficulties. b) Pre-stressed Concrete: Further development in pre-stressed concrete is hindered by the inability to produce high strength concrete, compactable with the high tensile steel available for pre-stressing.Since PIC provides a high compressive strength of the order of 100 to 140 MPa, it will be possible to use it for larger spans and for heavier loads. Low creep properties of PIC will also make it a good material for pre-stressed concrete. c) Marine Works: Aggressive nature of sea water, abrasive and leaching action of waves and inherent porosity, impair the durability of conventional concrete in marine works. PIC possessing high surface hardness, very low permeability and greatly increased resistance to chemical attack, is a suitable material for marine works. ) Desalination Plants: Desalination of sea water is being resorted to augment the shortage of surface and ground water in many countries. The material used in construction of flash distillation vessels in such works has to withstand the corrosive effects of disilted water, brine and vapour at temperature up to 1430 C. Carbon steel vessels which are currently in use are comparatively costly and deteriorate after prolonged use. Preliminary economic evaluation has indicated a savings in construction cost over that of conventional concrete by the use of PIC. ) Nuclear Power Plants: To cope up with the growing power requirements for industrial purposes, many countries are resorting to nuclear power generation. The Nuclear contained vessel (Pressure vessel) is a major element, which is required to withstand high temperatures and provide shield against radiations. Another attendant problem of nuclear power generation is the containment of spent fuel rods which are radioactive over long period of time to avoid radiation hazards. At present heavy weight concrete is being used for this purpose, which is not very eff ective.PIC having high impermeability coupled with high strength and marked durability provides an answer to these problems. f) Sewage Disposal Works: It is common experience that concrete sewer pipes deteriorate due to the attack of effluents and when buried in sulphate infested soils. Further in the sewage treatment plant, concrete structures are subjected to severe attack from corrosive gases particularly in sludge digestion tanks. Polymer-impregnated concrete due to its high sulphate and acid resistance, will prove to be a suitable material in these situations. ) Impregnation of Ferro-cement products: The ferro-cement techniques of construction is being extensively used in the manufacture of boats, fishing trawlers, domestic water tanks, grain storage tanks, man hole cover, etc. , Ferro cement products are generally this (1 to 4 cms) and as such are liable to corrode. Application of polymer impregnation techniques should improve the functional efficiency of ferro-cement products . h) Water Proofing of Structures: Seepage and leakage of water through roof and bathroom slabs, it a nagging problem and has not been fully over come by the use of conventional water proofing methods.The use of polymer impregnated mortar should solve this problem. i) Industrial Applications: Concrete has been used for floor in tanneries, Chemical Factories, dairy farms and in similar situations for withstanding the chemical attack, but performance has not been very satisfactory. The newly developed PIC will provide a permanent solution for durable flooring in such situations. 12. Case Studies: Two case studies are presented as follows: 1. Properties of Fiber Reinforced Polymer Concrete studied by Marinela Barbuta and Maria Harja 2. Polymer Concrete for Structural Restoration and Corrosion Protection of Concrete Support Columns.I. Properties of Fiber Reinforced Polymer Concrete studied by Marinela Barbuta and Maria Harja The experimental results of studies regarding polymer concrete with cellulose fibers are presented. The compositions used in the present study derive from a previous one which investigated a large number of compositions using different dosages of resin and filler. The mechanical characteristics such as: compressive strength, flexural strength and split tensile strength were investigated on fiber reinforced polymer concrete made with different dosages of resin and filler, the fiber dosage being constant for all mixtures.Materials The experimental researches on polymer concrete were made by using the following materials: polymer, fly ash as filler, crushed aggregates and fiber type ARBOCEL. The polymer was type epoxy resin, called ROPOXID, made in Romania by POLICOLOR Bucharest . The hardener was type ROMANID 407, also made by POLICOLOR Bucharest. The fly ash (FA) from the power plant CET Holboca, Jassy, was added to the fine aggregates. The fly ash is an inorganic waste produced by burning pulverized coal in power stations. Fly ash consists of many small, glass-like particles ranging in size from 0. 01 to 100 ? m.Chemically FA contains oxides, hydroxides, carbonates, silicates, and sulphates of calcium, iron and aluminum. The content in carbon is given from loss ignition. FA is a heterogeneous mixture of amorphous and crystalline phases and is generally considered to be a ferroaluminosilicate element. The mineralogical, physical and chemical properties of FA depend on the nature and composition of the coal, conditions of combustion, type of emission control devices, storage and evacuation methods. Storage methods may affect weathering rates, especially under humid conditions where soluble constituents may be leached.The principal characteristics of FA are: colour gray to black, function of carbon unburned, particles sizes between 0. 01 to 100 ? m; the shape of particles is spherical, specific surface is between 4,800. . . 5,200, the density is between 2,400 and 2,550 kg/m3 [ The aggregates were used in two sorts: 0. . . 4 mm and 4. . . 8 mm, with continuous granulosity, obtained from crushed river gravel by S. C. EMBERON SRL Jassy. The ARBOCEL fibers are natural cellulose fibers, produced by J. Rettenmaier & S? ohne GMBH. ARBOCEL is produced from cellulose in various qualities (fiber lengths, thicknesses, purities, etc. The properties of ARBOCEL cellulose fibers are: mean fiber length of 10 ? m, completely safe, insoluble in water and organic solvents, resistant to dilute acids and bases. The fiber was used in proportion of 3% from the mass of resin plus the hardener. Experimental Samples For the study of polymer concrete properties nine compositions (BPFF) were prepared in the experimental program (Table 1). [pic] The polymer concrete with different compositions as is given in Table 1, was prepared by mixing firstly the resin with hardener, then after complete homogenization the fibers were introduced in the mixture as shown in fig below [pic] Fig 1. Cellulose fiber mixing with resin. The fly ash w as added to the mix of aggregates and the resin and aggregates were mixed by the mechanical mixer. After complete mixing, the polymer concrete was poured in formworks. For each composition the density was determined. The following mechanical characteristics were experimentally tested: compressive strength on cube sample of 70. 7 mm sizes, flexural strength and split tensile strength on prismatic samples of sizes 210? 70? 70 mm, according to standard prescriptions. [pic] Fig. 2. – Samples of polymer concrete with fibers. Results and DiscussionsAccording to EN 12390/2001 the mechanical characteristics of polymer concrete with cellulose fiber, experimentally determined namely: compressivestrength (fc), flexural strength (fti) and split tensile strength (ftd) are given in Table below . [pic] From the experimental results the following observations can be made: a) The values of compressive strengths for polymer concrete with fibers (Fig. 3) vary between 62. 62 MPa (for BPFF7) and 46. 41 MPa (for BPFF2). Fig. 3. – Variation of compressive strength for polymer concrete with fiber. [pic] Fig. 3. – Variation of compressive strength for polymer concrete with fiber. ) With the increasing of resin and fly ash dosage the compressive strengths increase (Figs. 4 and 5). [pic] Compressive strength, MPa Fig. 4. – Variation of compressive strength for polymer concrete with fiber vs. the resin content, for 6. 4% FA. [pic] Fig. 5. – Variation of compressive strength for polymer concrete with fiber vs. the FA content, for 12. 4% resin. d) The values of flexure strengths for polymer concrete with fibers (Fig. 6)vary between 17. 57 MPa (for BPFF9) and 13. 55 MPa (for BPFF8), so, the decrease of resin dosage results in the increase of flexure strength. pic] Fig. 6. – Variation of flexural strength for polymer concrete with fiber. [pic] [pic] Fig. 7. – Variation of split tensile strength for polymer concrete with fiber: a – vs. t he resin content; b – vs. the sample number. d) The values of split tensile strengths for polymer concrete with fibers (Fig. 7) vary between 6. 94 MPa (for BPFF9) and 4. 29 N/mm2 (for BFF7); the increase of resin dosage results in the increase of split tensile strength. The experimental researches lead to the following observations: a) For the maximum epoxy resin dosage (16. %) compressive strength is reduced near minimum value, the flexure strength is medium, but the split tensile strength has high value. b) For the minimum epoxy resin dosage (12. 4%) compressive strength is reduced under the medium value, the flexure strength is also reduced, and the split tensile strength has value over the medium. c) For the maximum fly ash dosage (12. 8%) compressive strength and flexurestrength are medium, but the split tensile strength is near the highest value. d) For the minimum fly ash dosage (6. 4%) compressive strength and flexure strength are under the medium and the split tensil e strength is near medium value. ) For the same dosage of epoxy resin the maximum compressive strength and flexure strength were obtained for maximum fly ash dosage. It results that for increasing the compressive strength and flexure strength at same dosage of resin and fiber, it must be used the maximum dosage of fly ash. f) For the split tensile strength it must be used a medium fly ash dosage; The values of mechanical characteristics of polymer concrete are smaller then those of mechanical characteristics obtained for polymer concrete with silica fume and polymer concrete with fly ash . The author concluded that The experimental researches concerning the polymer concrete had investigatedthe mechanical characteristics of epoxy polymer concrete prepared with cellulose fibers and fly ash as filler. †¢ When the same dosage of cellulose fibers is used, the content of resin must be increased. Also for obtaining good mechanical properties the filler is used with higher dosages. â⠂¬ ¢ The experimental values of mechanical strengths for polymer concrete with cellulose fibers were smaller then that for polymer concrete without fibers. This type of fibers is not a good choice for polymer concrete reinforcement. II.Polymer Concrete for Structural Restoration and Corrosion Protection of Concrete Support Columns by David E. Snider and Heather M. Ramsey of Sauereisen Inc. A large copper mine and refinery in the western United States had a dilemma. Their cell house, which contains over 1,500 cells, each holding more than 20,000 gallons of electrolyte, had experienced severe corrosion and structural degradation of the support columns for the tanks. These columns support the cells in their solvent extraction and electrowinning process. This process entails immersion of a stainless steel cathode or â€Å"starter plate† into the electrolyte.Pure copper is deposited onto the starter plate during this 10-day digestion process. The collected copper is then further r efined at a separate location. Over time, highly acidic leakage from the cells had corroded the support columns to the point that their ability to adequately withstand the imposed load was in doubt. Additionally, the refinery desired to upgrade the facility’s ability to withstand seismic activity. The leakage, primarily copper sulfate and 25% sulfuric acid at a pH of 1. 0 or less, corroded not only the concrete but more significantly the reinforcement bar (rebar) encased in the concrete.Corrosion of the rebar resulted in an increase of internal pressure due to expansion of the corrosion products, therefore putting the concrete in high tensile stress. The direct effect of this stress was cracking and spalling of the concrete. Figure 1 shows a typical degradated column requiring restoration. [pic] The original construction of the columns used the rebar spaced 6-inches on center vertically and 18-inches on center horizontally. The refinery’s standard repair procedure was to remove corrosion products from the concrete and steel and then to top them with a polymer-modified portland-cement mortar.This standard repair method requires two (2) to three (3) days per column, and although temporarily affective, did not meet the company’s desire for a long-term solution. They decided upon a new approach using a polymer concrete (PC), which is a bisphenol A based-epoxy. This material is designed for maximum flowability, mechanical properties and chemical resistance. The PC repair system utilizes the polymer concrete for encapsulation, chemical protection, mechanical support and resistance to physical abuse. Figures 2 illustrates the method by which the stainless steel rebar was attached to the columns after surface-preparation.Stainless steel rebar was imbedded into the concrete floor using an epoxy mortar. Channels were saw-cut vertically in the concrete column. These channels provided a recess into which the rebar was bent and then secured into place with the epoxy mortar. Grouting of the rebar with this high strength epoxy mortar also served to provide tensile stress relief. By lowering stress relief, corrosion rates are reduced. [pic] Figure 2. Stainless steel rebar bent and grouted into the channels. To further ensure structural integrity and to upgrade seismic capabilities, the company chose to use fiberglass reinforcement (FRP) strips and wraps nder the PC. The strips were installed vertically on the columns and a fiberglass fabric was wrapped around the columns horizontally. The columns were formed and the polymer concrete was poured into place completely encapsulating the columns, the rebar and the FRP. This method required two (2) days per column. To date, 75 columns have been repaired using this method. Figures 3 and 4 show the forming and pouring of the PC. Figure 5 shows the PC after the form has been removed and the FRP that was applied to the columns. [pic] Figure 3. The forms placed around the column. . [pic] As me ntioned earlier, an important property of the PC is the flowability. The test for this property is ASTM C-143 and measures the â€Å"slump† of the polymer concrete. (Figure 6). A slump of 6 inches is considered to be flowable. This particular polymer concrete exhibits a slump of 8-inches, which is very flowable. Figures 6, 7 and 8 illustrate the flowability of the polymer concrete mixture. Table 1 lists some of the other physical properties of the polymer concrete used on this repair that were important considerations. [pic] Property at 7-days Value Property at 7- Days | Value | |Density |135 pounds/cft (2. 2gm/sq. cm) | |Compressive Strength |12,000 psi (84. 4 N/sq mm) | |Flexural Strength |3,000 psi (21. 1 N/ Sq. mm) | |Modulus of Elasticity |1. 08x 10(6)psi 7600 N/Sq mm | |Shrinkage` |0. 9 % | |Tensile Strength |2,400 psi (16. 9 N/Sq. mm) | The PC is roughly three times as strong as a portland cement mix (about 4,000 psi (281 kg / sq. cm. 28. 1 N/sq mm)) and is not chemic ally affected by the electrolyte. These properties make it an ideal product for the column restoration. As expected, none of the 75 columns repaired to date have exhibited any signs of failure and have required no maintenance since the repair program commenced in early 2007.Coatings will typically have a service life of 8 to 15 years depending upon the exposure and physical abuse. However, in this case, typical service life of coatings was six months. Their service life is also affected and somewhat limited as a result of application thickness. Coatings are generally applied at thicknesses ranging from a few mils up to a few hundred mils. Polymer concretes, however, are applied at a minimum thickness of 1 inch and may be applied as thick as 18 inches. The thickness of barrier coatings determines the overall permeability, which is a measure of water vapor’s ability to pass through a material.If the coating is less than 250 mils, the method used to determine permeability is bas ed on the water-vapor transmission (WVT) test ASTM E-96 or ASTM D-1653. Permeance is calculated from WVT. Permeability is obtained by multiplying permeance by thickness. A permeability of 10-8 (1. 49 x 10- 17 grams/Pa†¢s†¢m) or less is generally considered to provide a good barrier coating. Also due to the thickness, and other considerations, the service life of a polymer concrete is longer and requires far less maintenance. Experience with PCs by this manufacturer has shown no failures after 15 years of service.Laboratory evaluations coupled with field observations indicate the service life of PCs to be typically greater than 25 years. Figure 9 illustrates the completed column, including a protective topcoat for the FRP reinforced concrete. Although not needed for functionality, the topcoat was extended over the PC for aesthetics and coating integrity. [pic] Figure 9. Completed column repair. Many users of polymer concretes will entirely replace portland concrete with a f ull thickness of the polymer concrete. This is particularly true when extended downtimes are prohibitive. The lengthy cure time for standard portland based ement prior to receiving a protective coating is unacceptable for many facilities. After placement, polymer concretes may be placed into full chemical service after a 24-hour cure. Furthermore, with the strengths achieved with PC, it is usually possible to reduce the overall thickness to about ? of that commonly used with portland concretes. Typical thicknesses for PCs range from 1-inch to 4-inches. Polymer concretes may be engineered, formed and placed in the same manner that one would employ with a portland concrete structure. They also are reinforced in the same manner as portland concretes.Polymer concrete thicknesses are typically much less than that of the Portland concrete, therefore smaller diameter rebar is often used. At a thickness of 1 inch, one would use lesser thick rebar instead of a reasonably higher thick rebar c ommonly found with portland concrete constructions. Due to the ease of installation, the facility’s local preferred contractor was able to perform the work. The author concluded that Polymer concretes, which do not contain portland cement, have demonstrated tenacity as a protective barrier material in this difficult application and many others.This application required corrosion protection from a severely aggressive electrolyte, as well as protection from physical abuse. Other essential requirements were a system affording both ease of use and a quick turnaround time. Polymer concretes are also proving to be cost effective alternatives to using portland cement-based concretes with chemical-resistant topcoats for corrosion protection. The cost of maintenance for polymer concretes per year of service life is significantly less than that of concrete with applied barrier coatings, which may require multiple re-applications over the same number of years of service.Conclusion: 1. T he major factor that has been responsible for the extensive use of polymer-based materials in civil engineering is their advantages, viz . increased tensile strength, compressive strength, freeze-thaw durability, and decreased water permeability to a negligible value. 2. Owing to its excellent resistance to chemical attack i. e sulphate attack, acidic attack, saline water, radiation from nuclear substances polymer concrete has great potential over Portland cement for the design of structures in such industries, desalination plants, nuclear plants, underwater structures, overlays in bridge decks. . There are many type of application of repairing material available such as grout, motar, concrete, sprayed concrete and cement based material. Among these, resin based materials are performed much better than the others. 4. The cost of maintenance for polymer concretes per year of service life is significantly less than that of concrete with applied barrier coatings, which may require mult iple re-applications over the same number of years of service. 5. Extended use of pre stressed elements could be permitted with the reduced permeability possible. 6.The incorporation of dyes with the plastics used for polymerization opens another aesthetic aspect of concern to civil engineers and architects, as does the potential size decrease for greater span/depth ratios. 7. The only barrier to be focussed on is its higher cost in comparison to OPC and further research for economic production of polymer concrete would help to overcome this problem. References 1. â€Å"Properties of Fiber Reinforced Polymner Concrete†, Msrinela Barbuta and Maria Harja, Univerisity Technica, Tomul LIV(LVIII) Fasc,3, 2008, Constructii Architectura. . Muttukumar M. , Mohan D. J. , Polymer Res. 12, (2004) 3. â€Å"Polymer Concrete for Structural Restoration and corrosion protection of Concrete Support Columns† of David E. Snider and Heather M. Samsey of Sauereisen Inc. , 4. â€Å"Polymer concrete and its potential in the Construction industry†, Luke M. Snell,1 H. Aldridge Gillespie, and Robert Y. Nelson, Department of Civil Engineering, West Virginia University, Morgantown, West Virginia, and School of Civil Engineering and Environmental Science, University of Oklahoma Norman

Most important figure in American History Essay

Most important figure in American History - Essay Example "And it may be truly said, that never did nature and fortune combine more perfectly to make a man great" - Jefferson (Hawkinson, 2005: 243). Washington served in the American Revolutionary War as a commander in the Continental Army. He had been appointed in 1775 as Commander-in-Chief of the American revolutionary forces by the Continental Congress. The next year it was due to him that the British were driven out of Boston. He also failed New York City that same year plus went across the Delaware River in New Jersey. He astonished and defeated the enemy units. It was because of his tactics that the Revolutionary forces were able to capture the two major British combat armies at Saratoga and Yorktown. When the war was over Washington went back to his private life which prompted the surprised King George III to say, "If he does that, he will be the greatest man in the world" (Higginbotham, 2001: 221). Washington presided over the Philadelphia Convention which was responsible for drafting the Constitution of America due to there being mutual discontent with the Articles of Confederation. This happened in 1787 and two years later he became the president of the country (Freidel, 1994). Following his presidency he set up several customs and a using of the novel government's executive department. Washington attempted at creating a country that would have the capability of surviving in a world that was going down due to the ongoing war between Britain and France. He was in favor of plans for building a powerful central government which could be done if funded through the national debt, if there was an implementation of an efficient tax mechanism, and also through the creation of a national bank. Instead of going for war, Washington peacefully negotiated with Britain through the Jay Treaty in 1795. Washington was in favor of the programs organized by the Federalist Party but never actua lly joined the group. Washington is a great figure in American history and is perceived to be the country's identification plus said to be republicanism with regard to his practices. The early American politicians admired Washington greatly. He was given the first award of Congressional Gold Medal with the Thanks of Congress. Washington expired in the year 1799. Several scholars have named him as one of the greatest Presidents of United States. Biography Washington was born in the February of 1732 (Leibiger, 2001). His father passed away when he was 11 and his half brother assumed the part of his father. Washington experienced a lot of protectiveness and demand from his mother who did not allow him to join the British navy as Lawrence, his brother, wanted. When Washington was 16 he went on to live with Lawrence on Mount Vernon. He had his schooling at Colonial Virginia but did not go to college. In 1749 Washington became the surveyor for Culpepper County, Virginia. This happened following a trek for Lord Fairfax. From 1752 till 1758 he was in the military after which the Virginia House of Burgesses elected him. His speeches were in opposition to Britain's policies. Then he even became a leader in the Association. From 1775-1783 Washington led the Continental Army during the American Revolution after which, in 1787, he was made the president of the Constitutional Convention. Although

Unit 2 Individual Project Essay Example | Topics and Well Written Essays - 1000 words

Unit 2 Individual Project - Essay Example chieved while keeping in view the element of value addition in mind since sea food being a generic commodity; we believe our unique selling proposition will be value addition. Since the main market for our product is UAE which has very strict requirements for quality, therefore, our most important feature of the product will be the value addition. Our solo motto is producing quality seafood stuff which not only taking into account all the health related issues. We understand that for our customers it is very necessary that they receive nutrition which is on one hand is healthy and harmless to consume but it must also contain an element of taste and quality in it. Since Product quality, as a variable relating marketer’s action to consumer’s response largely depends upon the competitive positioning (Yoon & Kijewski, 1997)of the company therefore our product through its USP of freshness, quality and health consciousness will provide us the competitive positioning in the market. However, how a consumer makes a purchase decision depends upon how he or she is going to make a decision and whether the consumer either go through all the step or skip some and adopt other steps to make a purchase. The element of post purchase however can not be made before the purchase is actually done since after purchasing the product or service, consumer may either come up with positive or negative feedback about it. If we analyses the first stage of the process, we come to know that it is the stage where the actual need for the product and service arise. If at this stage, consumer is motivated enough, he will then proceed on to buy the product. In order to successfully launch our product, we believe there is a need for our product. Our industry analysis suggest that Being the coastal area, UAE always relied on the production and consumption of fish before the oil wealth started to flow into the UAE. Also due to more tourists being attracted to UAE, the demand for fish is also

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Landuse analysis of Famagusta Walled City - Essay Example If this trend continues unabated the city will be hollowed out both physically and socially; what is known as the doughnut syndrome. Moreover land is a finite resource and for an island like Cyprus which is an aggregarian island and much of its income depends on what it is able to grow, because this encroachment upon its green field not only eats up arable land but also destroys its biota. Even though several researches have been conducted on this specific area but they have offered palliatives rather than concrete or practical tools for implementation. This paper aims to highlight sustainable ways in which the city should be allowed to expand and develop and to bracket ways in which the theories advanced can be implemented in the city. Implementing this theory would mean redesign and development of the unused spaces according to smart growth theories and principles that oppose everything negative growth stands for. This constitutes tools for compact urban development which include the development of Brownfield sites, infill and mixed use of development and transit oriented

Informative publication Essay Example | Topics and Well Written Essays - 500 words

Informative publication - Essay Example This number is insignificant when you compare it with the number of graduates from our institution. For instance, it is evident that over 10,000 students graduated in the year 2013. Summing up all the students that have graduated since 2008 and then relating with the 2000 students with degrees in careers related with science will make you understand the impact of producing insignificant number of scientists. Our current world is changing every day from bad to worse. This is as results of technological changes that have contributed to the pollution as well as depletion of factors that hold the universe together. Majority of the world misuse cases are as a result of lack of awareness. Very few people know how to relate the daily occurrences with scientific reactions. For instance, very few people understand the impact of carbon dioxide to the ozone layer. Telling people that the carbon dioxide results to ozone layer depletion without explaining to them how it happens beats logic. We need to be in a position to explain some incidents in the universe by aid of evidence. It is as a result of this that we are holding a gland Science Congress meeting in our school. The poster that you will receive is designed in a very a unique way in order to grasp your attention. The title of the poster is in large fonts as well as bright colors so that you can see from a distance along expound what the whol e poster entails. The designs of other writings within the poster are meant to grasp your attention as well as convey the message concerning the title of the poster. The venue in which the Science Congress event will take place is written in large and bold fonts so that you can read it easily. The picture at the bottom and left side of the poster is of our guest of honor. Majority of you know Professor Lac Wal and others I think you have heard of him. Those who do not know him will also have

The Women's Kingdom - Mosuo Essay Example | Topics and Well Written Essays - 1750 words - 1

The Women's Kingdom - Mosuo - Essay Example tradition are highly controversial, including the ‘walking marriage’ or Axia marriage, the matriarchal family structure, the religion, and the interaction of the minority group with the outside world (PR China). This article seeks to address the controversial issues concerning the minority group, with verification of the facts from five interviewees from the community (appendix 1). A typical Mosuo family consists of ten family members, though the size varies and some may consist of between 20 and 30 members. Nonetheless, a female leads each family. In essence, the family head is the most proficient female in the house and all other members of the family respect her. She has important responsibilities and honorary status because all other members of the family depend on her decisions on family matters. Lugu Lake is the home for the Mosou community, which has about 35,000 to 50,000 members. The community enjoys plenty of space and building material for building, thus each family poses its own courtyard, with the number of rooms in each courtyard dependent on the size of the family. However, one room stands out: the grandmother’s quarters. The Mosuo family uses this room to offer sacrifices to ancestors, receptions, dining, and discuss family matters. However, the room has a dark atmosphere and low ceiling, creating a sense of intimacy with the only source of light coming from the flames in the coal-stove chambers. Here rests a stone representing the entire ancestry of the family (Vogt). Mosuo tradition holds that the stone carries the souls of the past generations, and thus the fire must remain lit throughout the year to keep the ancestor warm. In some families, the grandmother’s room may contain a big chink of meat that symbolizes the wealth of the family. The Mosou preserve the meat of slaughtered animals using salt and ash, then stitch up the skin and keep it dry in a shady and clean place. Such preserved meat usually lasts for over three years before

Point of View Paper Essay Example | Topics and Well Written Essays - 500 words

Point of View Paper - Essay Example The Confederate soldier would tell Farquhar that the Owl Creek Bridge had been taken, but if someone lit old driftwood on fire it would burn like tow. However, the Confederate soldier would warn Farquhar of the Union decree of death by hanging for anyone tampering with the railroad or bridges. Farquhar would not reply, but give a smug smile at the news. Then I would film Farquhar sliding off a plank and the rope snapping, with him plunging in the water. This scene should have a watch ticking in the background right before Farquhar slides off, and then snap back to actual sound when he hits the water. Shock should be filmed on the Union soldiers faces, with their fumbling for their guns. The next scenes shot would be Farquhar underwater. Lethargic at first, Farquhar would sink, and then come alive. He would slip out the ropes binding his arms, flinging off his noose, and come out of the water with a piercing shriek. The two soldiers on the bridge would be aiming and shooting at him. Since it takes a moment to reload, Farquhar would reach the sanding bank as the cannon fires a volley into the ground before him. Farquhar would reach the woods and flee. Then a couple of scenes of Farquhar running in the woods at night should be shot. One should show him running in fright, the next walking tiredly. Finally in the morning light, Farquhar should be shot walking with his eyes shut up a long driveway towards a two story home with six columns on the porch. He opens his eyes to run toward a woman dressed in a brown hoopskirt. As soon as he reaches her, the whole scene fades. The final shot should be of Farquhar’s swinging body on the bridge. It should not be of him falling, this would already been seen when the rope broke. Just his swinging body should be shot. A close up taken of the actor’s face might show a slight smile at the thought of being home. This would represent Farquhar’s peace at going home through death. To

Designing a Diversity Workshop for University Faculty Incorporating Research Paper

Designing a Diversity Workshop for University Faculty Incorporating Multicultural and International Objectives - Research Paper Example Diversity, in years gone by, was not embraced. In fact, it was often shunned to the point where the country saw many colleges and universities rise to the level one race, one religion, and one culture. To continue with this practice would not only be an injustice to students around the world who have come to cherish our individual freedoms and liberties, but it would service to deny faculty and the student body alike the privilege of learning in a multi-cultural environment. Understanding and accepting people of other cultures and beliefs do not have to be a daunting task. It simply requires compassion and a desire learn from and embrace others. Our university might be small in number, but we have the capacity to develop a cultural awareness that rivals institutions much larger than our own. Our own faculty is diverse, yet we have failed to tap into this reality. We should be making use of our broad range of professional and military experience in order to better understand the diver sity existent around us and to use the knowledge to impact our student body as well. This training program has been developed with our faculty in mind. It will focus on the instructional methodologies inherent in multicultural education, and it will create a sense of global awareness amongst us all that we must be conversant with the latest educational issues, diversity, and multicultural theory. It is in so doing that we will truly become a global institution who can make a positive impact in the field of education, while embracing multicultural diversity and becoming more accepting of each student and staff member who passes through our illustrious halls. Purpose There is no mistaking that the world is becoming increasingly diverse, yet this same diversity has not been reflected in the field of higher education. According to Hill, et. al (2011), only 10% of earned Doctorates in the fields of science, technology, engineering, and mathematics are represented by minority groups (p. 2 0). This not only leaves a great gap in these critical fields, but it indicates a troubling trend. If universities cannot embrace multicultural education, then society will be losing out on valuable learning opportunities moving forward. This purpose of this training workshop is to reverse this trend by providing faculty members with the tools necessary to incorporate multicultural education into the classroom, thereby encouraging diversity and an exchanging of scholarly and academic ideas across cultures. Embracing the diversity amongst us, a further purpose of this workshop will be to share various pedagogical techniques with one another that will serve to enhance our own multicultural understanding. Our students are increasingly coming from a diverse background and we must work together with all students to foster an atmosphere of understanding and respect. This begins with the faculty, each of who has valuable experience to draw from in the field of diversity education. Embracin g all people does require, to some extent, a shift in our way of thinking and the methods that we employ in our disciplines. It has been noted by some faculty members at other institutions that, â€Å"Fundamental and sustainable change is possible, given the right combination of vision, compromise, and commitment† (Grogan & Vaz, 2003, p. 35). It is this primary need for change that forms the basis for this