Monday, January 27, 2020
Photocatalytic Activity Investigation
Photocatalytic Activity Investigation The photocatalytic activity of the modified samples was investigated by the determination of the remaining concentration of the nominated pollutant, acetaldehyde, over various time intervals. Figures. 5 and 6 show the photodecomposition activity of different modified TiOà ¢Ã¢â‚¬Å¡Ã¢â‚¬Å¡ nanoparticles under 8w visible light irradiation in the continuous flow reactor with a flow rate of 95 ml/min. According to Figures. 5 and 6, all the modified samples show much higher photocatalytic activity than the pure TiOà ¢Ã¢â‚¬Å¡Ã¢â‚¬Å¡, confirming that N and Co doping is an effective way of improving the photocatalytic activity. The highest activity was observed for 1%Co-N-TiOà ¢Ã¢â‚¬Å¡Ã¢â‚¬Å¡ sample, and the 50 min irradiation by visible light resulted in 44.2% of acetaldehyde degradation for this sample. The increased visible light absorption and specific surface area are key factors that influenced the photoactivity of the different modified samples under visible light irradiation compared to pure TiO2. The decrease in the particle size and increase in the BET surface area (Table 1) contribute to the improvement of the acetaldehyde degradation. Table 1 shows that the crystallite size of samples decreases from 21.9 to 14.7 nm; this decrease may be beneficial for the photocatalytic activity. Compared with the N-TiO2 sample, Co-N/TiO2 photocatalysts have a larger surface area, which increases the photoactivity rate because of the large amounts of acetaldehyde molecules being adsorbed on the photocatalytic surface and easily reacted by photogenerated oxidizing species. The light absorption characteristics of the modified samples are extended towards the visible light region after N and Co doping, which implies that the formation of photogenerated charge carriers will be increased under visible light irradiation. Also, cobalt doping with a low cobalt content can act as a charge trap to prevent electron-hole recombination and improve the interfacial charge transfer to degrade acetaldehyde. After the optimal doping ratio of cobalt was exceeded (1wt % Co-N-TiO2), reduced photocatalytic activity was observed. This result can be due to the coverage of the surface of photocatalyst with increased cobalt ions (Co2+) which inhibited interfacial charge transfer due to inadequate amount of light energy available for activation of all the photocatalyst particles. Also due to excessive concentration, Co particles acting as recombination centers for photogenerated electrons and holes . Based on the acetaldehyde degradation results in this study, it is therefore evident that photocatalytic activity is strongly dependent on the doping ratio rather than the band gap of the samples and activities of the Co-N-TiO2 co-doped samples are higher than those of N-TiO2 or pure TiO2. **                    Fig. 5                   ** **                     Fig. 6                  ** Kinetic study The Langmuir-Hinshelwood kinetic model has been extensively used to describe heterogeneous photocatalysis on titanium dioxide . This model successfully describes the kinetic of Eq. (3), which is the reaction between hydroxyl radical and adsorbed acetaldehyde. When the photocatalytic reaction obeys a Langmuir-Hinshelwood model, the relationship between the rate of reaction r (ÃŽ ¼mol g-1 min-1) and the acetaldehyde concentration Cact. (ÃŽ ¼mol l-1) can be described as follows in Eq. (4): Where k is the rate constant (ÃŽ ¼mol g-1 min-1) and Ka is the adsorption constant (l ÃŽ ¼mol-1). Some assumptions were used in Eq. (4). Only acetaldehyde is adsorbed on the catalyst surface and all intermediates and products desorbed immediately after chemical reaction; therefore, they have not been detected in Eq. (4). The mathematical modelling for the plug photoreactor at unsteady condition with the assumption of isothermal condition, ignored diffusion resistance and constant flow rate, the mass balance equation inside the continuous photoreactor would become as follows in Eq. (5): Where Q is the volumetric flow rate (l min-1), W is the weight of catalyst (g), V is the volume of the reactor (l), and t is the time of experiment (min). Kinetic parameters (k, K) were calculated using the Nelder-Mead method, which was used through computer programming in MATLAB by minimization of sum of squared of relative error, the difference between the calculated and experimental outlet concentration results, as the following objective function: By minimization of Eq. (6), kinetic parameters (k, Ka) are predicted and shown in Table 3. A good agreement among the predicted and experimental data were found that are shown in Fig. 7.
Sunday, January 19, 2020
The Horse Dealer?s Daughter :: essays research papers
In D.H. Lawrence’s â€Å"The Horse Dealer’s Daughter,†Mabel â€Å"did not share the same life as her brothers †(195). Mabel Pervin was not close to her brothers, because there were personal and physical separations. Mabel was a plain, uninteresting woman. She seldom showed emotion on her face. In fact her face usually remained impassive and unchanged. Her brothers could be described as three handsome and well-spoken men. Mabel was independent, having taken care of the house for ten years without a servant. Even though they depended upon her, they seemed to have control over her. The Pervin brothers â€Å"did not care about anything†(195). They were poised and felt secure about themselves. Her brothers felt superior to her. â€Å"They had talked at her and round her for so many years, that she hardly heard them at all†(196). She would either give a neutral response to her brothers, or remain quiet when they talked to her. Instead of giving her encouragement, they teased her. This treatment could have led to her insecurity. They would tease her about becoming a maid or about her â€Å"bulldog†face. Her brothers were full of energy and very talkative. Mabel also seemed to be alone in the world. Unlike her brothers who had many companions, she had had no friends of her own sex. Sometimes it seemed that Mabel wanted to escape her life. One place Mabel felt secure and immune from the world was at her mother’s grave. â€Å"There she always felt secure, as if no one could see her†(200). Mabel was extremely devoted to her deceased parents, especially her mother. She was mindless and persistent. At the graveside, she had many different feelings. She seemed to be coming nearer to her own glorification. Also she would become remote and intent. She seemed to feel contact with the world that mother had lived.
Saturday, January 11, 2020
Effect on the Economy Essay
Francis Mr. Joseph English 12 26 November 2012 War: Effect on Economy War has influenced economic history profoundly across time and space. Winners of wars have shaped economic institutions and trade patterns. Wars have influenced technological developments. Above all, recurring war has drained wealth, disrupted markets, and depressed economical growth. Wars are expensive (in money and other resources), destructive (of capital and human capital), and disruptive (of trade, resource availability, labor management). Large wars make up severe shocks to the economies of participating countries. Despite some positive aspects of short-term stimulation and long-term destruction and rebuilding, war generally impedes economic development and undermines wealth. Several specific economic effects of war recur across historical eras and locales. Next inflation, the most consistent short-term economic effect of war is to push up prices, and consequently to reduce living standards. This war-induced inflation was described in ancient China by the strategist Sun Tzu: â€Å"Where the army is, prices are high; when prices raise the wealth of the people is exhausted†(Tzu Sun, c. 00 BCE) His advice was to keep wars short and have the money in hand before assembling an army. Paying for wars is a central problem for states (see War Finance). This was especially true in early modern Europe (fifteenth to eighteenth centuries), when war relied heavily on mercenary forces. The king of Spain was advised that waging war required three things – money, money, and more money. Spain and Portugal imported silver and gold from America to pay for armies, but in such large quantities that the value of these metals eventually eroded. One way governments pay for war is to raise taxes (which in turn reduces civilian spending and investment). U. S. revolutionary Thomas Paine warned in 1787 that â€Å"war †¦ has but one thing certain, and that is to increase taxes. †Another way to pay for war is to borrow money, which increases government debt, but war-related debts can drive states into bankruptcy as they did to Spain in 1557 and 1596. A third way to fund war is to print more currency, which fuels inflation. Inflation thus often acts as an indirect ax on a national economy to finance war. Industrial warfare, and especially the two World Wars, created inflationary pressures across large economies. Increasingly, governments mobilized entire societies for war – conscripting labor, bidding up prices in markets for natural resources and industrial goods, and diverting capital and technology from civilian to military applications. World War I caused ruinous inflation as participants broke from the gold standard and issued currency freely. Inflation also accompanied the U. S. Civil War, World War II, and the Vietnam War, among others. War-induced inflation, although strongest in war zones, extends to distant belligerents, such as the United States in the World Wars, and, in major wars, even to neutral countries, owing to trade disruption and scarcities. Present-day wars continue to fuel inflation and drive currencies towards worthlessness. In Angola’s civil war (1975-2002), for example, the government currency became so useless that an alternative â€Å"hard†currency – bottles of beer – came to replace it in many daily transactions. In addition to draining money and resources from participants’ economies, most wars create zones of intense destruction of capital such as farms, factories, and cities. These effects severely depress economic output. The famine and plague that accompanied the Thirty Years’ War (1618-48) killed as much as one-third of Germany’s population, as mercenaries plundered civilians and civilians became mercenaries to try to survive. World War I reduced French production by nearly half, starved hundreds of thousands of Germans to death, and led to more than a decade of lower Soviet output. One estimate put World War I’s total cost at $400 billion – five times the value of everything in France and Belgium at the time. Battle casualties, war-induced epidemics, and other demographic disruptions have far-reaching effects. World War I contributed to the 1918 influenza epidemic that killed millions. Military forces in East Africa may have sparked the outbreak of what became a global AIDS epidemic. Quincy Wright estimates that â€Å"at least 10 percent of deaths in modern civilization can be attributed directly or indirectly to war†(Wright, 1942). The U. S. â€Å"baby boom†after World War II continues decades later to shape economic policy debates ranging from school budgets to social security. Wars also temporarily shake up gender relations (among other demographic variables), as when men leave home and women take war jobs to replenish the labor force, as in the Soviet Union, Britain, and the United States during World War II. Countries that can fight wars beyond their borders avoid the most costly destruction (though not the other costs of war). For example, the Dutch towards the end of the Thirty Years’ War, the British during the Napoleonic Wars, the Japanese in World War I, and the Americans in both World Wars enjoyed this relative insulation from war’s destruction, which meanwhile weakened their economic rivals. Also, just as wars’ costs and outcomes affect economic conditions and evolution, so too do economic conditions and evolution affect war. Causality runs in both directions. For example, Dutch economic strengths in the early 17th century allowed fast and cheap production of ships, including warships. The resulting naval military advantage in turn supported Dutch long-distance trade. The wealth derived from that trade, in turn, let the Netherlands pay and train a professional standing army, which successfully sheltered the Netherlands from the ruinous Thirty Years’ War. This protection in turn let the Dutch expand their share of world trade at the expense of war-scarred rivals. Thus the evolutions of warfare and of world economic history are intertwined. War is the proximal cause of the recurring inflationary spikes that demarcate 50-year â€Å"Kondratieff waves†in the world economy. Those waves themselves continue to be controversial. However, they may have some predictive value to the extent they clarify the historical relationships between war and military spending on the one hand, and inflation and economic growth on the other. The 1990s mainly followed a predicted long-wave phase of sustained low inflation, renewed growth, and reduced great-power military conflict. If this pattern were to continue, the coming decade would see continued strong growth but new upward pressures on military spending and conflict, eventually leading to a new bout of inflation in the great-power economies. Since scholars do not agree on the mechanism or even the existence of long economic waves, however, such projections are of more academic than practical interest. The relationship between military spending and economic growth has also generated controversy. Despite its pump-priming potential in specific circumstances, as during the 1930s, military spending generally acts to slow economic growth, since it diverts capital and labor from more productive investment (such as in roads, schools, or basic research). During the Cold War, high ilitary spending contributed (among other causes) to the economic stagnation of the Soviet Union and the collapse of North Korea, whereas low military spending relative to GDP contributed to Japan’s growth and innovation. During the 1990s, as real military spending worldwide fell by about one-third, the United States and others reaped a â€Å"peace dividend†in sustained expansion. However, effects of military spending are long-term, and sh arp reductions do not bring quick relief, as Russia’s experience since 1991 demonstrates. The global North-South divide – a stark feature of the world economy – is exacerbated by war. The dozens of wars currently in progress worldwide form an arc from the Andes through Africa to the Middle East and Caucasus, to South and Southeast Asia. In some of the world’s poorest countries, such as Sudan and Afghanistan, endemic warfare impedes economic development and produces grinding poverty, which in turn intensifies conflicts and fuels warfare. To conclude, you have read about the good and bad things of war effects on the economy. War has drained wealth, disrupted markets, and depressed economical growth. But, the winners of these wars often were rewarded from these wars. War is bad overall; I feel that war should be the last option for any country. Works Cited Washigntonsblog. â€Å"Proof that war is bad for the economy. †24 Feb. 2012. < http://www. washingtonsblog. com/2012/02/debunking-the-myth-that-war-is-good-for-the-economy-once-and-for-all. html>. Symonds, Peter. â€Å"US wages over war†. 7 Oct. 2012. < http://www. globalresearch. ca/us-wages-economic-war-on-iran/5307485. > < http://www. joshuagoldstein. com/jgeconhi. htm. > <upsky2. triod. com/science/economics/waraffectseconomy. html. > <Www, joshuagoldstein. com/igeconhi. htm. >
Friday, January 3, 2020
The Iditarod Trail Sled Dog Race and Animal Cruelty
The Iditarod Trail dog sled race is a sled dog race from Anchorage, Alaska to Nome, Alaska, a route that is over 1,100 miles long. Aside from basic animal rights arguments against using dogs for entertainment or to pull sleds, many people object to the Iditarod because of the animal cruelty and deaths involved. â€Å"[J]agged mountain ranges, frozen river, dense forest, desolate tundra and miles of windswept coast . . . temperatures far below zero, winds that can cause a complete loss of visibility, the hazards of overflow, long hours of darkness and treacherous climbs and side hills.†This is from the official Iditarod website. The death of a dog in the 2013 Iditarod has prompted race organizers to improve protocols for dogs removed from the race. History of the Iditarod The Iditarod Trail is a National Historic Trail and was established as a route for dog sleds to access remote, snowbound areas during the 1909 Alaskan gold rush. In 1967, the Iditarod Trail Sled Dog Race began as a much shorter sled dog race, over a portion of the Iditarod Trail. In 1973, race organizers turned the Iditarod Race into the grueling 9-12 day race that it is today, ending in Nome, AK. As the official Iditarod website puts it, â€Å"There were many who believed it was crazy to send a bunch of mushers out into the vast uninhabited Alaskan wilderness.†The Iditarod Today The rules for the Iditarod require teams of one musher with 12 to 16 dogs, with at least six dogs crossing the finish line. The musher is the human driver of the sled. Anyone who has been convicted of animal cruelty or animal neglect in Alaska is disqualified from being a musher in the Iditarod. The race requires the teams to take three mandatory breaks. Compared to previous years, the entry fee is up and the purse is down. Every musher who finishes in the top 30 receives a cash prize. Inherent Cruelty in the Race According to the Sled Dog Action Coalition, at least 136 dogs have died in the Iditarod or as a result of running in the Iditarod. The race organizers, the Iditarod Trail Committee (ITC), simultaneously romanticize the unforgiving terrain and weather encountered by the dogs and mushers, while arguing that the race is not cruel to the dogs. Even during their breaks, the dogs are required to remain outdoors except when being examined or treated by a veterinarian. In most U.S. states, keeping a dog outdoors for twelve days in freezing weather would warrant an animal cruelty conviction, but Alaskan animal cruelty statutes exempt standard dog mushing practices: This section does not apply to generally accepted dog mushing or pulling contests or practices or rodeos or stock contests. Instead of being an act of animal cruelty, this exposure is a requirement of the Iditarod. At the same time, Iditarod rules prohibit â€Å"cruel or inhumane treatment of the dogs.†A musher may be disqualified if a dog dies of abusive treatment, but the musher will not be disqualified if â€Å"[T]he cause of death is due to a circumstance, nature of the trail, or force beyond the control of the musher. This recognizes the inherent risks of wilderness travel.†If a person in another state forced their dog to run over 1,100 miles through ice and snow and the dog died, they would probably be convicted of animal cruelty. It is because of the inherent risks of running the dogs across a frozen tundra in sub-zero weather for twelve days that many believe the Iditarod should be stopped. The official Iditarod rules state, â€Å"All dog deaths are regrettable, but there are some that may be considered unpreventable.†Although the ITC may consider some dog deaths unpreventable, a sure way to prevent the deaths is to stop the Iditarod. Inadequate Veterinary Care Although race checkpoints are staffed by veterinarians, mushers sometimes skip checkpoints and there is no requirement for the dogs to be examined. According to the Sled Dog Action Coalition, most of the Iditarod veterinarians belong to the International Sled Dog Veterinary Medical Association, an organization that promotes sled dog races. Instead of being impartial caregivers for the dogs, they have a vested interest, and in some cases, a financial interest, in promoting sled dog racing. Iditarod veterinarians have even allowed sick dogs to continue running and compared dog deaths to the deaths of willing human athletes. However, no human athlete has ever died in the Iditarod. Intentional Abuse and Cruelty Concerns about intentional abuse and cruelty beyond the rigors of the race are also valid. According to an ESPN article: Two-time runner-up Ramy Brooks was disqualified from the Iditarod Trail Sled Dog Race for abusing his dogs. The 38-year-old Brooks hit each of his 10 dogs with a trail marking lathe, similar to a surveyors stake, after two refused to get up and continue running on an ice field [...] Jerry Riley, winner of the 1976 Iditarod, was banned for life from the race in 1990 after he dropped a dog in White Mountain without informing veterinarians the animal was injured. Nine years later, he was allowed back in the race. One of Brooks’ dogs later died during the 2007 Iditarod, but the death was believed to be unrelated to the beating. Although Brooks was disqualified for beating his dogs, nothing in the Iditarod rules prohibits mushers from whipping the dogs. This quote from The Speed Mushing Manual, by Jim Welch, appears on the Sled Dog Action Coalition: A training device such as a whip is not cruel at all but is effective [...] It is a common training device in use among dog mushers [...] A whip is a very humane training tool [...] Never say whoa if you intend to stop to whip a dog [...] So without saying whoa you plant the hook, run up the side Fido is on, grab the back of his harness, pull back enough so that there is slack in the tug line, say Fido, get up immediately rapping his hind end with a whip. As if dog deaths were not enough, the rules allow mushers to kill moose, caribou, buffalo, and other large animals â€Å"in defense of life or property†along the race. If the mushers were not racing in the Iditarod, they wouldn’t encounter wild animals defending their territory. Breeding and Culling Many of the mushers breed their own dogs for use in the Iditarod and other sled dog races. Few dogs can become champions, so it is common practice to cull the unprofitable dogs. An email from former musher Ashley Keith to the Sled Dog Action Coalition explains: When I was active in the mushing community, other mushers were open with me about the fact that larger Iditarod kennels frequently disposed of dogs by shooting them, drowning them or setting them loose to fend for themselves in the wilderness. This was especially true in Alaska, they said, where veterinarians were often hours away. They often used the phrase Bullets are cheaper. And they noted that its more practical for mushers in remote parts of Alaska to do it themselves. The Mushers Although the mushers endure some of the same harsh conditions faced by the dogs, the mushers decide voluntarily to run the race and are fully aware of the risks involved. The dogs do not make such decisions knowingly or voluntarily. The mushers can also voluntarily decide to drop out and walk away when the race is too difficult. In contrast, individual dogs are dropped from the team when they are sick, injured or dead. Furthermore, the mushers are not whipped if they are going too slow. Changes After Dog Death in 2013 In the 2013 Iditarod, a dog named Dorado was removed from the race because he was moving stiffly. Dorados musher, Paige Drobny, continued the race and, following standard protocol, Dorado was left outside in the cold and the snow at a checkpoint. Dorado died of asphyxiation after being buried in snow, although seven other dogs who were also covered in snow survived. As a result of Dorados death, race organizers plan to build dog shelters at two checkpoints and also check on the dropped dogs more frequently. More flights will also be scheduled to transport dropped dogs from checkpoints that are not accessible via roads. What Can I Do? You dont have to be a member of PETA to believe in animal rights. Even with the entry fee, the Iditarod loses money on each musher, so the race relies on money from corporate sponsors. Urge the sponsors to stop supporting animal cruelty, and boycott sponsors of the Iditarod. The Sled Dog Action Coalition has a list of sponsors as well as a sample letter.
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