Hydrogen Fuel Cell Vehicles Essay Example for Free

Hydrogen Fuel Cell Vehicles Essay The first hydrogen fuel cell was invented in 1839 by William Groves who conducted an experiment that proved electric current could be produced from a electrochemical reaction between hydrogen and oxygen. He named the invention a gas voltaic battery. For 120 years the technology layed dormant until 1959 when a modified farm tractor was produced with 15 kilowatt fuel cell. In 1966 the first hydrogen fuel cell road vehicle was made, it had a range of 120 miles and a maximum speed of 70 mph. Due to high production costs the hydrogen fuel cell vehicle program was canceled. For thirty years the hydrogen fuel cell was used for space exploration. In 2003 a government initiative was announced to promote the hydrogen fuel cell vehicle. Hydrogen fuel cells can significantly reduce emissions of greenhouse gasses and theoretically could replace the internal combustion engine. There are a variety of challenges that face further development of the fuel cell vehicle. As of 2014 a total of about 60 hydrogen refueling stations are avaliable to the public worldwide. In the Unitied States there are 12 hydrogen refueling stations 10 of which are located in California. Hydrogen fuel costs 400% more to produce than gasoline. There is a high amount of energy that is needed to make hydrogen into fuel. Hydrogen fuel is stored pressurized form in complex storage tanks. The fuel is kept at a low temperature if hydrogen fuel comes into contact with human skin it can cause immediate frost bite. When there is an improperly designed or damaged valve in a hydrogen vehicle it can cause the tank to over pressurize and explode. Hydrogen fuel is extremely flammable if it comes into contact with an oxidizer such as oxygen it immediately catches fire and burns with an invisible flame. In a car accident a ruptured tank can explode from depressurization. Hydrogen fuel can leak into a cars interior, the driver would be unaware of the odorless gas and be breathing no oxygen if the air conditioning is on recycle causing loss of conciseness or asphyxiation. As of 2014 the range of a hydrogen vehicle is 100 miles on average to 300 miles maximum. A 20 gallon gasoline tank is the equivalent of an 80 gallon hydrogen fuel tank. The National Research Council reported in February 2004 The DOE should halt efforts on high pressure tanks and cryogenic liquid storage. They have little promise of long term practicality for lite duty vehicles. In 2015 Toyota will release its first production hydrogen fuel cell mid size sedan for the price of $70,000. Honda has a hydrogen fuel cell vehicle at the cost of $120,000. There are prototype hydrogen fuel cell vehicle models being produced by a number of auto makers. A May 2008 scientific study in Wired News reported experts say it will be 40 years or more before hydrogen has any meaningful impact on gasoline consumption or global warming, and we cant afford to wait that long. In the meantime, fuel cells are diverting resources from more immediate solutions.

Mercantilism Essay -- Economics

Mercantilism Mercantilism is the economic theory that a nation's prosperity depends on its supply of gold and silver; that the total volume of trade is unchangeable. This theory suggests that the government should play an active role in the economy by encouraging exports and discouraging imports, especially through the use of tariffs. Spain and England used the mercantile system to benefit the mother countries. The mercantile system had special regulations, which usually extracted some sort of reaction from the colonies. If necessary, the policies would be changed to better suit the mother country. The favorable balance of trade was upheld through certain regulations. No foreign trade was allowed for the colony unless it passed through the mother country first and it moved on mother country ships. Furthermore, no foreign settlers were allowed in the colony. No colonial industry was allowed. The colony had to remain dependent on the mother country for industrial necessities, it was not allowed to become competition for foreign markets, and migrations restrictions limited availability of skilled artisans. Regulatory taxation was another mercantile regulation. Protective â€Å"tariffs† were used on foreign imports to the colony, and revenue was raised for the mother country. No colonial self-government was allowed, either. The mother country avoided challenges to its economic authority, and the colonies couldn’t enact pro colonial/anti-mother country laws. The Spanish used three mercantilist devices to protect their commercial monopoly in the New World. They prohibited foreign ships from entering Spanish colonial ports, and no foreigner could send goods to the colonies or take gold bullion out of Spain in pay... ...land, vigorous attempts to prevent smuggling in the American colonies after 1765 led to arbitrary seizures of ships and aroused hostility. The legislation had an unfavorable effect on the Channel Islands, Scotland (before the Act of Union of 1707), and especially Ireland, by excluding them from a preferential position within the system. Shaken by the American Revolution, the system, along with mercantilism, fell into decline. The acts were finally repealed in 1849. Mercantilism was widely used in many different superpowers in the 18th century. Depending on what superpower used it, the colonies under the superpowers were restricted from doing certain things, and had to follow certain mercantile regulations. The mercantile systems most likely ended up with the colonies undergoing revolutions (America and England) which resulted in the end of mercantilism. Mercantilism Essay -- Economics Mercantilism Mercantilism is the economic theory that a nation's prosperity depends on its supply of gold and silver; that the total volume of trade is unchangeable. This theory suggests that the government should play an active role in the economy by encouraging exports and discouraging imports, especially through the use of tariffs. Spain and England used the mercantile system to benefit the mother countries. The mercantile system had special regulations, which usually extracted some sort of reaction from the colonies. If necessary, the policies would be changed to better suit the mother country. The favorable balance of trade was upheld through certain regulations. No foreign trade was allowed for the colony unless it passed through the mother country first and it moved on mother country ships. Furthermore, no foreign settlers were allowed in the colony. No colonial industry was allowed. The colony had to remain dependent on the mother country for industrial necessities, it was not allowed to become competition for foreign markets, and migrations restrictions limited availability of skilled artisans. Regulatory taxation was another mercantile regulation. Protective â€Å"tariffs† were used on foreign imports to the colony, and revenue was raised for the mother country. No colonial self-government was allowed, either. The mother country avoided challenges to its economic authority, and the colonies couldn’t enact pro colonial/anti-mother country laws. The Spanish used three mercantilist devices to protect their commercial monopoly in the New World. They prohibited foreign ships from entering Spanish colonial ports, and no foreigner could send goods to the colonies or take gold bullion out of Spain in pay... ...land, vigorous attempts to prevent smuggling in the American colonies after 1765 led to arbitrary seizures of ships and aroused hostility. The legislation had an unfavorable effect on the Channel Islands, Scotland (before the Act of Union of 1707), and especially Ireland, by excluding them from a preferential position within the system. Shaken by the American Revolution, the system, along with mercantilism, fell into decline. The acts were finally repealed in 1849. Mercantilism was widely used in many different superpowers in the 18th century. Depending on what superpower used it, the colonies under the superpowers were restricted from doing certain things, and had to follow certain mercantile regulations. The mercantile systems most likely ended up with the colonies undergoing revolutions (America and England) which resulted in the end of mercantilism.

Analysis of Theoretical Framework

Analysis of Theoretical Framework EDUC 701: Theories and Research in Educational Psychology February 24, 2013 ? Introduction Teachers are required to teach reading and comprehension skills to students and help them be able to read and comprehend materials from the past and present. Dr. Constance L. Pearson (1990) writes a dissertation entitled â€Å"The Comparison of the Effects of Three Prereading Advance Organizers on the Literal Comprehension of Fifth-Grade Social Studies Materials† in this paper he is trying to see if the use of a prereading advanced organizer would help build the fifth grade students comprehension and knowledge skills.During this stage of students learning development it is very important to start working on their reading and comprehension skills. Analysis The theoretical framework for this dissertation is using fifth-grade social studies materials and having a prereading strategy of an advanced organizer to see if it would increase comprehension and know ledge in the children while they read their textbooks. The advanced organizers that are being used are visual, graphic and problematic situation approach. The advanced organizers are being used to help the students with any concepts that they are not familiar with.By using these organizers strategies would be developed to help assist in learning the material. There were two research questions to validate the theory that is being used. The first question related to reading comprehension and how it affects students when they are given a prereading activity while using one of the advanced organizers. The second research question relates to the reading comprehension of the other two advanced organizer approaches when they are given a preading activity. It is believed that students reading comprehension can be increased from the use of the advanced organizers for their particular subject area.The purpose of this research was to determine if one of the prereading advance organizer strateg ies would carry distinction from the other two approaches. During the research many factors had to be considered and one such factor were students not being able to derive meaning from what they read in content area textbooks. One reason that the reader may have a problem with content text is that the material is written on a higher reading level then the intended reader. As a result the writers have tried to simplify the terminology and shortened the sentences.They did not take into consideration factors that inherent in the reader such motivation, reading ability and interest. There is one human factor that has the most influence on comprehension and that is schemata. Comprehension of the material is being determined by the knowledge that the reader brings to the selection. The more schemata the reader has for the topic the more they will understand the topic. Content materials especially in the area of social studies seek to develop many concepts; students often do not have the f ramework to attach new knowledge.Students must have an understanding of the concepts in order to comprehend the material they are reading. In chapter two of the dissertation Pearson explains how the research and literature that relate to the relationship of advance organizers to reading comprehension. He discusses the history of the study of reading comprehension and advance organizers. The schema theory is discussed as it relates to the study of advance organizers. Before 1970 reading comprehension was viewed as a process solely activated by the text itself.The views on reading comprehension have since changed and now text has been determined to be only the framework for meaning. The reader must be able to construct an internal conceptual representation of what is being read. Conclusion Therefore, through research it was determined the usage of advance organizers before the materials were read, did bring about some remembering by activating important concepts that were already pres ent in the children’s cognitive structure. The usage of advanced organizers should reinforce the importance of the new materials by providing the framework of previous learning materials.To determine if the usage of advanced organizers remain effective you should upon its ability to support new ideas from the student’s previous ideas. The prereading strategy of advanced organizers introduces how students can attach concepts to new learning materials Reference Pearson, C. L. P. (1990). The comparison of the effects of three prereading advance organizers on the literal comprehension of fifth-grade social studies materials. (Doctoral Dissertation). University of Tennessee, Knoxville, TN.

What Was Life Like During the Pax Romana

Pax Romana is Latin for Roman Peace. The Pax Romana lasted from about 27 BCE (the reign of Augustus Caesar) until CE 180 (the death of Marcus Aurelius). Some date the Pax Romana from CE 30 to the reign of Nerva (96-98 CE). How the Phrase Pax Romana Was Created Edward Gibbon, author of The History of the Decline and Fall of the Roman Empire is sometimes credited with the idea of the Pax Romana. He writes: Notwithstanding the propensity of mankind to exalt the past and to depreciate the present, the tranquil and prosperous state of the empire was warmly felt and honestly confessed by the provincials as well as Romans. They acknowledged that the true principles of the social life, laws, agriculture, and science, which had been first invented by the wisdom of Athens, were now firmly established by the power of Rome, under whose auspicious influence the fiercest barbarians were united by an equal government and common language. They affirm that, with the improvement of arts, the human species was visibly multiplied. They celebrate the increasing splendor of the cities, the beautiful face of the country, cultivated and adorned like an immense garden; and the long festival of peace, which was enjoyed by so many nations, forgetful of their ancient animosities, and delivered from the apprehension of future danger. What Was the Pax Romana Like? The Pax Romana was a period of relative peace and cultural achievement in the Roman Empire.It was during this time that monumental structures such as Hadrians Wall, Neros Domus Aurea, the Flavians Colosseum and Temple of Peace were built. It as also later called the Silver Age of Latin literature. Roman roads traversed the empire, and the Julio-Claudian Emperor Claudius established Ostia as a port city for Italy. The Pax Romana came after an extended period of civil conflict in Rome. Augustus became emperor after his posthumously adoptive father, Julius Caesar, was assassinated. Caesar had begun a civil war when he crossed the Rubicon, leading his troops into Roman territory. Earlier in his life, Augustus had witnessed the fighting between his uncle-by-marriage Marius and another Roman autocrat, Sulla.The famous Gracchi brothers had been killed for political reasons. How Peaceful Was the Pax Romana? The Pax Romana was a time of great achievement and relative peace within Rome. Romans no longer fought one another, by and large. There were exceptions, such as the period at the end of the first imperial dynasty, when, after Nero committed suicide, four other emperors followed in rapid succession, each deposing the previous one violently. The Pax Romana did not mean Rome was at peace vis-a-vis the peoples at its borders. Peace in Rome meant a strong professional army stationed mostly away from the heart of the Empire, and instead, at the roughly 6000 miles of frontiers of imperial frontier. There werent enough soldiers to spread evenly, so the legions were stationed at the locations thought most likely to cause trouble. Then, when the soldiers retired, they generally settled in the land where they had been stationed. To maintain order in the city of Rome, Augustus established a sort of police force, the vigiles. The praetorian guard protected the emperor.