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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Effect of microwave radiation on Fe/ZSM-5 for catalytic conversion of methanol to hydrocarbons (MTH)

Ntelane, Tau Silvester 03 1900 (has links)
The effect of microwave radiation on the prepared 0.5Fe/ZSM-5 catalysts as a post-synthesis modification step was studied in the methanol-to-hydrocarbons process using the temperature-programmed surface reaction (TPSR) technique. This was achieved by preparing a series of 0.5Fe/ZSM-5 based catalysts under varying microwave power levels (0–700 W) and over a 10 s period, after iron impregnating the HZSM-5 zeolite (Si/Al = 30 and 80). Physicochemical properties were determined by XRD, SEM, BET, FT-IR, C3H9N-TPSR, and TGA techniques. It was found that microwave radiation induced few changes in the bulk properties of the 0.5Fe/ZSM-5 catalysts, but their surface and catalytic behavior were distinctly changed. Microwave radiation enhanced crystallinity and mesoporous growth, decreased coke and methane formation, decreased the concentration of Brønsted acidic sites, and decreased surface area and micropore volume as the microwave power level was increased from 0 to 700 W. From the TPSR profiles, it was observed that microwave radiation affects the peak intensities of the produced hydrocarbons. Application of microwave radiation shifted the desorption temperatures of the MTH process products over the HZSM-5(30) and HZSM-5(80) based catalysts to lower and higher values respectively. The MeOH-TPSR profiles showed that methanol was converted to DME and subsequently converted to aliphatic and aromatic hydrocarbons. It is reasonable to suggest that microwave radiation would be an essential post-synthesis modification step to mitigate coke formation and methane formation and increase catalyst activity and selectivity. / Chemical Engineering / M. Tech. (Chemical Engineering)
212

Вдувание в доменную печь нагретого пылеугольного топлива совместно с дисперсным железосодержащим сырьем : магистерская диссертация / Injection of heated pulverized coal fuel into a blast furnace together with dispersed iron-containing raw materials

Антонов, Н. А., Antonov, N. A. January 2024 (has links)
Приведены показатели анализа и обоснование необходимости вдувания в горн заранее нагретого пылеугольного горючего и оксидов железа – аспирационной пыли. Использование именно этого железорудного сырья обосновано желанием утилизировать отходы газоочистки на разных этапах производства и экономией на подготовке сырья. Определён эффект этих действий на показатели доменной плавки при изменениях дутьевых режимов работы печи главным образом на расход кокса и производительность печи. / The analysis indicators and justification for the need to inject preheated pulverized coal fuel and iron oxides - aspiration dust - into the furnace are given. The use of this particular iron ore raw material is justified by the desire to utilize gas purification waste at different stages of production and to save on the preparation of raw materials. The effect of these actions on the performance of blast furnace smelting with changes in the blast operating conditions of the furnace was determined, mainly on coke consumption and furnace productivity.
213

A theological response to the "illegal alien" in federal United States law

Heimburger, Robert Whitaker January 2014 (has links)
Today, some twelve million immigrants are unlawfully present in the United States. What response to this situation does Christian theology suggest for these immigrants and those who receive them? To this question about the status of immigrants before the law, the theological literature lacks an understanding of how federal U.S. immigration law developed, and it lacks a robust theological account of the governance of immigration. To fill this gap, the thesis presents three stages in the formation of the laws that designate some immigrants as aliens unlawfully present or illegal aliens, drawing out the moral argumentation in each phase and responding with moral theology. In the first stage, non-citizens were called aliens in U.S. law. In response to the argument that aliens exist as a consequence of natural law, Christian teaching indicates that immigrants are not alien either in creation or for the church. In the second stage, the authority of the federal government to exclude and expel aliens was established, leaving those who do not comply to be designated illegal aliens. To the claim that the federal government has unlimited sovereignty over immigration, interpretations of the Christian Scriptures respond that divine sovereignty limits and directs civil authority over immigration. In the third stage, legal reforms that were intended to end discrimination between countries allowed millions from countries neighboring the U.S. to become illegal aliens. These reforms turn out to be unjust on philosophical grounds and unneighborly on theological grounds. While federal law classes many as aliens unlawfully present in the United States, Christian political theology indicates that immigrants are not alien, the government of immigration is limited by divine judgment, and nationals of neighboring countries deserve special regard.
214

”By the iron hand of oppression" : The performance of the parliamentary election contest in Nottingham and Middlesex 1802-1803

Blomgren, Alvar January 2017 (has links)
The aim of this thesis is to investigate how politics was done at the level of the parliamentary constituencies at the time of the treaty of Amiens 1802-1803. This is achieved through two case studies of the elections in Middlesex and Nottingham, which are investigated as social practices. This thesis argues that understandings of masculinity and national identity, as well as questions about the nature of the constitution and citizen rights were central to participants in the extraparliamentary political process. Collective emotions were also highly important in the process of mobilising political support, and this thesis emphasises that participation in these elections was a collective effort; men and women from all levels of society were significant political actors. Moreover, this thesis demonstrates the importance of competences such as knowledge about the organisation of crowds and political violence in the performance of the election.
215

A Pragmatic Standard of Legal Validity

Tyler, John 2012 May 1900 (has links)
American jurisprudence currently applies two incompatible validity standards to determine which laws are enforceable. The natural law tradition evaluates validity by an uncertain standard of divine law, and its methodology relies on contradictory views of human reason. Legal positivism, on the other hand, relies on a methodology that commits the analytic fallacy, separates law from its application, and produces an incomplete model of law. These incompatible standards have created a schism in American jurisprudence that impairs the delivery of justice. This dissertation therefore formulates a new standard for legal validity. This new standard rejects the uncertainties and inconsistencies inherent in natural law theory. It also rejects the narrow linguistic methodology of legal positivism. In their stead, this dissertation adopts a pragmatic methodology that develops a standard for legal validity based on actual legal experience. This approach focuses on the operations of law and its effects upon ongoing human activities, and it evaluates legal principles by applying the experimental method to the social consequences they produce. Because legal history provides a long record of past experimentation with legal principles, legal history is an essential feature of this method. This new validity standard contains three principles. The principle of reason requires legal systems to respect every subject as a rational creature with a free will. The principle of reason also requires procedural due process to protect against the punishment of the innocent and the tyranny of the majority. Legal systems that respect their subjects' status as rational creatures with free wills permit their subjects to orient their own behavior. The principle of reason therefore requires substantive due process to ensure that laws provide dependable guideposts to individuals in orienting their behavior. The principle of consent recognizes that the legitimacy of law derives from the consent of those subject to its power. Common law custom, the doctrine of stare decisis, and legislation sanctioned by the subjects' legitimate representatives all evidence consent. The principle of autonomy establishes the authority of law. Laws must wield supremacy over political rulers, and political rulers must be subject to the same laws as other citizens. Political rulers may not arbitrarily alter the law to accord to their will. Legal history demonstrates that, in the absence of a validity standard based on these principles, legal systems will not treat their subjects as ends in themselves. They will inevitably treat their subjects as mere means to other ends. Once laws do this, men have no rest from evil.

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