Final Exam in Principles of Sociology Essay Example | Topics and Well Written Essays - 1250 words

Final Exam in Principles of Sociology - Essay Example The lungs of the asthma patients shrink considerably, and when they breathe they feel like ‘breathing through a straw’. Stratification makes it difficult for many asthma patients to receive timely health care and many low income class people find it almost impossible to afford effective treatments for the disease. The huge amount of money spent on medical treatment and medical bills make it impossible for them to have other necessities of life such as good hosing and healthy living conditions. All these add to their personal troubles and miseries. An understanding of Mills’ perception of the sociological imagination is important in understanding the macro-level forces that contribute to public issues like asthma. Mills perceives sociological imagination as a way of thinking that believes that human behavior is shaped through social interaction; according to him, one’s personal experiences are always linked to the social contexts such as the prevailing milieu, the connection between history and biography, and the realization that one’s personal troubles are often the results of public issues of social culture. He believes that the sociological imagination would enable one to â€Å"understand the larger historical scene in terms of its meaning from the inner life and the external career of a variety of individuals† (Cargan & Ballantine 30). The social forces that contribute to asthma are the unequal distribution of power and income, the psychological and social constraints that the asthma patients ar e subject to in the American society. While medical practitioners hold that asthma can be prevented through â€Å"right medication, clean air, and a reasonably stress-free life†, many low-income asthma patients feel that this is â€Å"both well-intentioned and useless† (Corbett 59). The low-income asthma patients are very often unable to pay the huge amount of medical bills and these unpaid medical bills cause mental and psychological

Effect of Zn Concentration on NiZnFe2O4 Nanoparticles

Effect of Zn Concentration on NiZnFe2O4 Nanoparticles CHAPTER-7 EFFECT OF Zn CONCENTRATION ON MAGNETIC AND DIELECTRIC PROPERTIES OF NiZnFe2O4 NANOPARTICLES 7.1 INTRODUCTION Ni (1-x) Zn (x) Fe2O4 (x=0.2, 0.4 and 0.6) nanoparticles are synthesized by using coprecipitation method. Zinc is a known metal, its role is important in the modification of ferrite properties by redistribution over the tetrahedral and octahedral sites of the spinel lattice. Rath et al (2002) reported the effect of zinc substitution on lattice parameter and magnetic properties on Mn-Zn ferrites prepared by hydrothermal precipitation method. Arulmurugan et al (2005) studied the effect of zinc substitution on Co-Zn and Mn-Zn ferrite nanoparticles prepared by coprecipitaion method. This chapter discusses the effect of zinc concentration on structural, magnetic and dielectric properties of NiZnFe2O4 nanoparticles prepared by co-precipitation method. The detailed experimental procedure involved in the preparation of NiZn ferrite nanoparticles has been already reported in chapter IV. In this method three different compositions such as x=0.2, x=0.4 and x=0.6 were used in the chemical formula Ni (1-x) Zn(x) Fe2O4 to analyze the properties of the ferrite nanoparticles. 7.2 RESULTS AND DISCUSSION 7.2.1 X-ray Diffraction (XRD) analysis The average crystallite size ‘t’ and the lattice parameter ‘a’ were calculated from X-ray diffraction data as reported in the chapter –IV. The values of particle size and Lattice parameter of all samples are also tabulated in Tables 7.1, 7.2 and 7.3. The particle size decreased from 24 to 12nm with the increase of Zn concentration. The same behavior of decrease in particle size with the increase of zinc concentration was also observed for the samples sintered at 600 °C and 900 °C. The decrease in particle size due to the increase of zinc concentration was 26 to 20nm for sintered sample at 600 °C and 31 to 25 nm for sintered sample at 900 °C respectively. This variation of particle size with zinc concentration at the above mentioned sintering temperature of Ni Zn ferrites nano particles is shown in Fig.7.1. The above observation shows that the presence of zinc blocks the grain growth. The surface temperature affects the molecular concentration at the surface of the crystal, and hence, the crystal growth (Upadhyay et at 2004). The formation of Zn-ferrite is more exothermic as compared with the formation of Ni-ferrite (Navrotsky Kleppa 1968). Thus, the crystal surface temperature increases with addition of zinc, decreasing the molecular concentration at the crystal surface and hence, obstructing the grain growth. The effects of zinc concentration on structural, magnetic and dielectric properties of Ni-Zn ferrite nano particles were studied. Particle size decreased with the increase of concentration. This decreasing in particle size behavior was observed for all the categories of concentration variation at different sintering temperature levels. The effect of zinc concentration on particle size showed a reverse effect compared with the effect of sintering temperature (chapter-IV), in which the particle sizes increased with the increase of sintering temperature. Table 7.1Particle size and Lattice parameter of as prepared Ni (1-x) Zn (x) Fe2O4 (x= 0.2, 0.4 and 0.6) nano particles Table 7.2 Particle size and Lattice parameter of Ni (1-x) Zn (x) Fe2O4 (x= 0.2, 0.4 and 0.6) nano particles sintered at 600 °C Table 7.3 Particle size and Lattice parameter of Ni (1-x) Zn (x) Fe2O4 (x= 0.2, 0.4 and 0.6) nano particles sintered at 900 °C From Tables 7.1, 7.2 and 7.3 it is also observed that the lattice parameter increases with the increase of zinc concentration. The lattice parameter value for as prepared are increased from 8.33 to 8.37Ã… with the increase of zinc. For the samples sintered at 600 °C the lattice parameter value for lower zinc concentration (x=0.2) is 8.63Ã… and higher zinc concentration (x=0.6) is 8.66 Ã…. The similar behavior of increase in lattice parameter with zinc concentration is also observed as 8.64 to 8.68 Ã… in the samples sintered at 900 °C. This increase of lattice parameter with zinc concentration for all sintering temperatures of Ni Zn ferrites nano particles are also shown in Fig.7.2. The addition of Zn2+ in Ni-ferrite causes the Fe3+ ions to migrate from A site to B site. The larger ionic radius of zinc (0.82Ã…), compared with ferric ion (0.67 Ã…), makes the A site and thus the lattice expands, increasing the lattice parameter. A similar variation of particle size and lattice parameter with zinc content had been observed by Joshi Kulkarrni (1986) for Mg-Zn Ferrite. Fig.7.1Variation of particle size with zinc concentration for all sintering temperatures Fig.7.2Variation of lattice parameter with zinc concentration for all sintering temperature 7.2.2 Magnetic Properties The room temperature B-H hysteresis loops of Ni (1-x) Zn (x) Fe2 O4 nano particles for different zinc concentration (x = 0.2, 0.4 and 0.6) sintered at 600 °C and 900 °C are shown in Figs.7.3 (a), 7.3 (b) and 7.3 (c). The variations of magnetic properties such as saturation magnetization (Ms), and coercivity (Hc) for different zinc concentrations (x = 0.2, 0.4 and 0.6) at particular sintering temperature were calculated from the hysteresis data and tabulated in Tables 7.4, 7.5 and 7.6. Table 7.4 Saturation magnetization and coercivity values of as prepared Ni (1-x) Zn (x) Fe2O4 (x= 0.2, 0.4 and 0.6) nano particles Table 7.5 Saturation magnetization and coercivity values of Ni (1-x) Zn (x) Fe2O4 (x= 0.2, 0.4 and 0.6) nano particles sintered at 600 °C Table 7.6 Saturation magnetization and coercivity values of Ni (1-x) Zn (x) Fe2O4 (x= 0.2, 0.4 and 0.6) nano particles sintered at 900 °C The effect of zinc concentration on magnetic properties such as saturation magnetization and coercivity of all compositions of Ni Zn ferrite nano particles sintered at 600 °C and 900 °C are shown in Figs.7.4 and 7.5. The Fig.7.4 reveals that the saturation magnetization (Ms) decreases with the increase of zinc concentration. The saturation magnetization value decreased from 29.73 to 6.98 emu/g with the increase of zinc concentration for as prepared samples. The saturation magnetization value for the 600 °C sintered samples at lower zinc concentration (x=0.2) was 32.78 emu/g and higher zinc concentration (x=0.6) was 25.80 emu/g. A similar behavior of decrease in saturation magnetization with zinc concentration was also observed in the samples sintered at 900 °C as 64.34 to 39.50 emu/g. Fig.7.3 Hysteresis loops of Ni (1-x) Zn (x) Fe2 O4 nano particles for different zinc concentration (x = 0.2, 0.4 and 0.6) (a) as prepared (b) 600 °C sintered (c) 900 °C sintered samples This decreasing of saturation magnetization with the increase of non magnetic Zn concentration is due to the interaction created by the zinc in the tetrahedral and octahedral sites. This shows the weakening of A-B interaction, whereas B-B interaction changes from ferromagnetic to antiferromagnetic state. The occurrence of minor decrease in saturation magnetization is also evidenced from the dielectric study, because it shows that there is a minor increase in dielectric constant. This reason leads to the conclusion that saturation magnetization variation with respect to concentration for 600 °C and 900 °C samples did not cause a rapid decrease in saturation magnetization like as prepared sample. Fig.7.5 shows that the coercivity values of NiZn ferrite nanoparticles decrease with the increase of zinc concentration. The coercivity values of as prepared nanoparticles decrease from 324.36 to 306.56 Gauss. Similarly the variation of coercivity values of nanocrystalline NiZn ferrite particles with increase of Zn concentration sintered at 600 °C and 900 °C are in the range of 347.31- 340.72 Gauss and 386.67-351.34 Gauss. This is due to the decreases of magneto crystalline anisotropy constant. The magneto crystalline anisotropy constant is negative for both Ni and Zn ferrites. The absolute value of magneto crystalline anisotropy constant larger for Ni ferrites than that of Zn ferrites (Verma et al 2000). The total anisotropy is equal to the sum of their individual anisotropy. So magneto crystalline anisotropy constant and hence coercivity decreases with the increase in Zn concentration. Also reasons behind the decrease in saturation magnetization and decrease in coercivity are c learly identified from the formation of smaller particle size even at the higher Zn concentration at all sintering temperatures. Fig.7.4 Variation of saturation magnetization with zinc concentration Fig.7.5 Variation of coercivity with zinc concentration 7.2.3 Dielectric properties The effect of zinc concentration on dielectric constant of all samples of Ni (1-x) Zn (x) Fe2 O4 nano particles are shown in Figs.7.6 (a), 7.6 (b) and 7.6 (c). The values of dielectric constant and dielectric loss are tabulated in Tables 7.7, 7.8 and 7.9. Fig.7.6 Dielectric constant curves of Ni (1-x) Zn (x) Fe2 O4 nano particles for different zinc concentration (x = 0.2, 0.4 and 0.6) (a) as prepared (b) 600 °C sintered (c) 900 °C sintered samples Fig. 7.7 Dielectric loss curves of Ni (1-x) Zn (x) Fe2 O4 nano particles for different zinc concentration (x = 0.2, 0.4 and 0.6) (a) as prepared (b) 600 °C sintered (c) 900 °C sintered samples The dielectric constant attained for zinc concentration x =0.6 led to a higher value for all the samples. The variations of dielectric constant with zinc concentration for all samples are also shown in Fig. 7.8. For all as prepared samples, the dielectric constant value increased from 10.92 to 25.08 with the increase of zinc concentration. The dielectric constant value for the samples sintered at 600 °C in lower zinc concentration (x=0.2) was 15.33 and it increased to 32.86 at higher zinc concentration (x=0.6). A similar behavior of increase in dielectric constant with increase in zinc concentration was also observed in the samples sintered at 900 °C as 19.37 to 48.18. Table 7.7 Dielectric constant and Dielectric loss values as prepared Ni (1-x) Zn (x) Fe2O4 (x= 0.2, 0.4 and 0.6) nano particles Table 7.8 Dielectric constant and Dielectric loss values of  Ni (1-x) Zn (x) Fe2O4 (x= 0.2, 0.4 and 0.6) nano particles  sintered at 600 °C Table 7.9 Dielectric constant and Dielectric loss values of  Ni (1-x) Zn (x) Fe2O4 (x= 0.2, 0.4 and 0.6) nano particles  sintered at 900 °C Figs.7.7 (a), 7.7 (b) and 7.3 (c) show the effect on zinc concentration on dielectric loss factor of all samples of Ni (1-x) Zn (x) Fe2 O4 nano particles. The variation of dielectric loss factor value with zinc concentration for all sintering temperatures is also shown in Fig. 7.9. For all as prepared samples the dielectric loss factor value increased from 0.59 to 1.36 with the increase of zinc concentration. For the samples sintered at 600 °C the dielectric loss factor value for lower zinc concentration (x=0.2) was 0.68 and at higher zinc concentration (x=0.6) it was 1.61. A similar behavior of increase in dielectric loss with increase in zinc concentration was also observed in the samples sintered at 900 °C as 1.34 to 2.14. In Ni-Zn ferrites Zn occupies [A] site and Ni occupies [B]site, while Fe occupies both [A] and [B] sites. When Zn2+ is added in the place of Ni2+, with increase in Zn composition x, some of the Fe3+ ions get converted into Fe2+ ions. This increases the hopping between Fe3+ and Fe2+ ions, thereby decreasing the resistance of the grain. This increases the probability of electrons reaching the grain boundary. Hence the polarization and the dielectric constant increase. Fig.7.8 Variation of dielectric constant with zinc concentration Fig.7.9 Variation of dielectric loss with zinc concentration 7.3 CONCLUSION The effects of zinc concentration on structural, magnetic and dielectric properties of Ni-Zn ferrite nano particles were studied. The increase in zinc concentration obstructed the grain growth and decreased the particles size. The larger ionic radius of Zn, increased the lattice parameter values of NiZn ferrite nanoparticles with the increase of its concentration. The non magnetic property of zinc, decreased the saturation magnetization and coercivity values of NiZn ferrite nanoparticles. The dielectric constant and dielectric loss factor values also increased with the increase of zinc concentration due to the increase of probability of electrons reaching the grain boundary. Low value of particle size obtained at higher zinc concentration in the present work indicated that NiZn ferrite nano particles in lower nanometer scale could be obtained at higher zinc concentration.

Teen People Magazine Essay -- BTEC Business Marketing GCSE Coursework

Teen People Magazine The Teen People, September edition, is a magazine designed to appeal to young female readers. Its content features well known celebrities, use of bright and flashy colors, and an organized layout that attracts an upbeat, young readership interested in high-quality appearance and style. Although the magazine’s main focus may appear to insure a great fashion sense, it also concentrates on a philosophical orientation by covering a more diverse readership that includes all colors, sizes, and shapes of females. Teen People also expands its audience by recognizing both visual and text oriented audiences. To appeal to the more visual oriented audience, the magazine uses exotic photography in the advertisements for Self Esteem, Secret Deodorant, and Ralph Lauren. For the more text oriented audience, the magazine includes celebrity profiles on Ruben Studdard as well as both Nick Lachey and Jessica Simpson. Whether the audience is visual or text oriented, Teen People’s main objec tive is to create an animated and enjoyable magazine for young female readers. The advertisement for the clothing line Self Esteem uses an imaginative idea of a human butterfly to catch the eye of its visual oriented viewers (117). The advertisement pictures a young Mediterranean female with butterfly wings attached to her back. She is dressed in casual attire with green cargo pants and a simple khaki colored shirt. The unusual depiction and choice in clothing may insinuate that an athletic female reader can effectively express herself by dressing comfortably in Self Esteem clothing wear. The smile and happy indication illustrates that freedom of originality leads to eternal happiness. Self Esteem places the young female in the midst of... ...emales tend to desire. Self Esteem uses a deeper level of thinking to portray beauty. Secret Deodorant tends to advertise angelic beauty, whereas companies such as Ralph Lauren advertise natural beauty. Although both articles use big celebrities to attract their readers, they tend to differ in who is attracted and why they are attracted to the article. Whatever the approach may be, Teen People Magazine accurately appeals to all types of people who desire a good style sense, information on their favorite celebrities, and overall beauty. Works Cited Ralph Lauren advertisement. Teen People. September 2005: 51. Ruben Studdard Article. Teen People. September 2005: 176. Secret Deodorant advertisement. Teen People. September 2005: 64. Self Esteem advertisement. Teen People. September 2005: 117. "They’ve Got Game." Teen People. September 2005: 190.

History of HTML Essay

HTML or HyperText Markup Language is the predominant and most currently most popular language for creating web pages. It is a well-designed language to describe the structure of text-based information in a document by using certain tags referred to as HTML tags and using certain text links, heads, paragraphs, tables, lists and headings. While HTML is written in the form of tags, surrounded by angle brackets. HTML can also describe, to some degree, the appearance and semantics of a document, and can include embedded forms, and other scripting language codes, which can affect the behavior of Web browsers and other HTML processors. It is assumed that what made this language a very popular web development language is its English-like characteristic which makes it relatively easy to comprehend, and memorize the tags as compared to most other languages. It was in the late 1980’s, when the physicist Tim Berners-Lee, who was an independent contractor at CERN, proposed and prototyped ENQUIRE, a system for CERN researchers to use and share documents. In 1989, Berners-Lee and CERN Robert Cailliau, a data systems engineer from CERN, each submitted separate proposals for an Internet-based hypertext system providing similar functionality. The following year, they collaborated on a joint proposal, the Worldwide Web (W3) project; this proposal was accepted by CERN and as of now, and the project continued to grow from the day that it was developed, and continuous to grow up until present. In the advent of the interne and in the continuous increase in its popularity, came parallel the advent of the web-development language HTML. Although it has already been an accepted and established concept in the field of academics as early as the 1940s. It was with the advent of he personal computer that hypertext came into popularity. Bill Atkinson came up with the astounding idea in the late 1980s. It was then the he and his team developed Hypercard, an application for the Macintosh Operating System. Hypercard allows users to construct a series of on-screen `filing cards’ that would be able to contain text and graphics. Users can also navigate through these filing cards by pressing on-screen buttons, which were designed for simple and plain navigation. Hypercard easily became popular and was integrated on many other applications. Toolbox, for Personal Computers was developed and popularized in the 1990s for hypertext training courses. These courses came up with a more advanced navigation system wherein viewers or users were able to view pages with buttons which can help them navigate forward or backward or jump to a topic. Hypercard and its co-programs easily became popularized, however they were still held back by certain limitations. The major limitation was that hypertext jumps were only allowed to be made to files on the same computer. Hypertext umps to computers on other countries or on the other side of the world were still not possible. Hypertext communication was still on the local scale and not available in the global scale. It the increasing demands for global scale hypertext communication that the HTML came into advent. HTML has had a development-span of roughly seven years. During that time, it has evolved from a simple language with a small number of tags to a complex system of mark-up tags, enabling authors to create visually stunning web pages complete with sound and animation. Basically, the language developed from HTML+, HTML 2, HTML 3. 2, HTML 4. And finally HTML 5, which was released in 2008. A document called â€Å"HTML Tags†, was the first publicly available description of the HTML. This was known to public by Tim Berners-Lee in 1991. It describes 22 elements comprising the initial, relatively simple design of HTML, thirteen of these elements still exist up to HTML 4. At that time, Berners-Lee considered HTML to be an application of Standard Generalized Markup Language or SGML. However, it was not formally announced until the mid-1993 publication, by the IETF, of the first proposal for an HTML specification. Berners-Lee and Dan Connolly’s made an internet draft, â€Å"Hypertext Markup Language (HTML)†. This included an SGML document type definition to define the grammar. The HTML and HTML+ drafts expires in 1994, and that was when IETF created an HTML Working Group, which in 1995 completed â€Å"HTML 2. 0†, the first HTML specification intended to be treated as a standard against which future implementations should be based. HTML 2. 0 included ideas from the HTML and HTML+ drafts. HTML 2. 0 became the standard for website design until the year 1997. By then, more people were using HTML, and while the previous standards offered some decent abilities, people thirsted for more abilities and tags as to be able to better enhance the appearance of their websites. At this time, a HTML working group, led by Dave Raggett introduced HTML 3. 0. It included many new and improved abilities for HTML, and promised far more powerful opportunities to HTML users. HTML 4. 0 was recommended by W3C in 1997 and became the official standard in April 1998. Browser support was undertaken surprisingly earnestly by Microsoft in their Internet Explorer browser HTML 4. 0 was a large evolution of the HTML standards, and the last version of the classic HTML. At present, the newest version of the HTML is HTML 5. 0. It was published as a working draft by W3C last January 22, 2008, and includes major revisions in the core language of the World Wide Web, HTML. In this version, new features, elements and functionalities had been introduced to aid web developers to further improve the appearance and back-end structure of websites.

Automobile and Tucker Essay

The movie, Tucker: The Man and His Dream, is the story of a man named Preston Tucker and takes place in the 1940’s. Preston Tucker’s dream was to design and build the greatest automobile ever made. At first, he began by bringing home drawings of his dream car, which was to be called the Tucker Torpedo. He showed the drawings to a man who would eventually become his partner, Abe. Initially, Abe doesn’t like the idea of building a car, but he didn’t know anything about cars. Tucker placed an advertisement in a magazine about his car, and the public became excited. The car would have an engine in the rear, a middle headlight that turned with the car, and a windshield that would pop out when the car was in a wreck. In the meantime, Robert Bennington, who was the CEO of Ford, became worried that the Tucker Torpedo may put Ford out of business, so Bennington made a deal with him to allow him to buy a plant to build the car in. This also gave Ford a reason to be involved in building the car. The deal stated that Tucker must make at least fifty cars in one year in order to keep the plant, and the first car needed to be presented to the public within sixty days. Abe invested $6,000 to help Tucker build the first car. On the day of the presentation, the car was built but had no engine. Therefore, they had some problems getting it on stage, but once it was on stage, the thousands of people who attended the presentation cheered. After that, Bennington announced to Tucker that he wanted to change the car. He didn’t want the engine in the rear of the car, and since the ? Big 3†², the three largest automobile makers in the US, were buying all of the steel, there was not enough for Tucker to buy to build his cars. Tucker protested the ? Big 3†². A man named Howard Hughes, who owned a steel company, told Tucker about a helicopter company who needed to sell steel. So Tucker bought a helicopter engine and converted it to a car engine, and the car worked. After Tucker protested the ? Big 3†², he was spied on by people who worked for the ? Big 3†² companies. They accused him of not running his business properly, but it was not true. Abe got scared because he had already served three years in prison for bank fraud and did not want to get caught up in another mess, so he resigned. Then, there were commercials out that told the public that Tucker’s car was built piece by piece from a junkyard. Eventually, the government started a full investigation on Tucker and charged him with fraud. Tucker lost most of his investors from this, and had already spent too much money trying to build the car. He did make all the cars, but he did not make the fifty car minimum in time and lost his plant. He was found not guilty of fraud, but after all the bad publicity, people no longer wanted the cars, and Tucker had lost a lot of money, so no more cars were ever made. Today, some of Tucker’s Torpedo’s are still around; some are in museums, and some of them even still run. After watching the movie, I researched the Tucker Tornado on the Internet. One source, The History of the Tucker 48, at www. gizmohighway. com, says that the car actually had additional features not mentioned in the movie. In addition to the turning headlight, rear engine and the windshield that would pop out, the Tucker Torpedo also had more room inside the car and padded steering wheels and dashboards. Another source, 1946 Tucker Torpedo, at www.cybersteering. com, also says that Tucker applied for a $30 million loan before he was accused of fraud and that in 1956, Tucker died of lung cancer in Brazil while trying to build another car, the Carioca. I also found in the open letter from Preston Tucker, at www. tuckerclub. org, that this is a letter that Preston Tucker wrote to protest the other automobile companies and the investigations that eventually killed his company. In it he says that he actually had 1,872 Tucker dealers and almost 50,000 investors that put $25 million into his company. The definition of an entrepreneurship is a person who organizes and manages a business, assuming the risk for the sake of a profit. Preston Tucker started a company and wanted to build a car for Americans knowing that it would take a lot of money that he did not have. He organized and managed the business and assumed the risk of losing a lot of money for a lot of people. I think that Tucker was not treated fairly by his competition. New entrepreneurs like Preston Tucker should be given the same fair chance to build a business just like the others had to build theirs.