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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.
1

Immunomagnetic cell separation continued development of fundamental model of magnetophoretic mobility and further applications /

Zhang, Huading. January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Document formatted into pages; contains xix, 219 p. Includes bibliographical references. Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2005 Oct. 29.
2

Essai critique sur la notion du patrimoine en droit français et en droit égyptien

Ghānim, Ismāʻīl. January 1957 (has links)
Thesis--Paris.
3

Separation of rhodium (III) and iridium (IV) using functional polymeric materials

Majavu, Avela January 2014 (has links)
Poly(vinylbenzylchloride) (PVBC) nanofibers were fabricated by the electrospinning process. The Merrifield micropheres, silica microsparticles and PVBC nanofibers were functionalised with different quaternary diammonium groups derived from ethylenediamine (EDA), tetramethylenediamine (TMDA), hexamethylenediamine (HMDA), 1,8-diaminooctane (OMDA), 1,10-diaminodecane (DMDA) and 1,12-diaminododecane (DDMDA) and investigated for separation of [RhCl5(H2O)]2- and [IrCl6]2-. The sorbent materials were characterised by means of FTIR, XPS, SEM, BET surface area, thermogravimetric analysis and elemental analysis, and characterization results showed that the functionalization of the sorbent materials was successful. Batch equilibrium studies were carried out to assess the efficiency of these different anion exchangers using single metal aqueous solutions. The adsorption isotherms and kinetics of both [RhCl5(H2O)]2- and [IrCl6]2- adsorption onto the sorbent materials are presented. The isothermal batch adsorption studies fitted the Freundlich model indicating heterogeneous surface adsorption. The Freundlich isotherm confirmed multilayer adsorption and the Freundlich constant (kf) displayed the following ascending order for nanofibers (F-QUAT EDA, F-QUAT TMDA, F-QUAT HMDA, F-QUAT OMDA and F-QUAT DMDA), silica microparticles (Si-QUAT EDA, Si-QUAT TMDA, Si-QUAT HMDA, Si-QUAT OMDA and Si-QUAT DMDA) and microspheres (B-QUAT EDA, B-QUAT TMDA, B-QUAT HMDA, B-QUAT OMDA and B-QUAT DMDA) and a decrease in kf for F-QUAT DDMDA, Si-QUAT DDMDA and B-QUAT DDMDA has been observed. The pseudo second-order model was found to be the best fit to describe the adsorption kinetics of both metal ions complexes onto all the sorbent materials. K2 value in pseudo second-order kinetics showed that the rate constant for adsorption of [IrCl6]2- onto nanofibers was larger than for silica microparticles and Merrifield microspheres. Column sorption of [IrCl6]2- and [RhCl5(H2O)]2- was carried out and the loading capacities of [IrCl6]2- were obtained, and they showed dependence on the length of the methylene spacer between the two diammonium centres. [RhCl5(H2O)]2- was not adsorbed by the sorbent materials while [IrCl6]2- was loaded onto the column. The highest iridium loading capacities for all the sorbent materials for the diamines with decylene spacer, and were found to be 32.94 mg/g, 29.35 mg/g, and 27.09 mg/g for F-QUAT DMDA, Si-QUAT DMDA and B-QUAT DMDA respectively. It was also observed on the derivatives of DMDA supported on nanofibers that F-QUAT ethyl loading capacity for iridium (19.89 mg/g) reduced which may be due to the electron-donating nature of the ethyl group and the increase of hydrophobicity whereas F-QUAT benzyl loading capacity (244.64 mg/g) increased dramatically due to increase in the size of the cation which lowers the positive charge density of the quaternary diammonium center. The charge delocalizing ability of the benzyl group resulted in the best interaction of the diammonium group derived from this quaternizing agent, yielding the highest loading capacity for [IrCl6]2-. Reusability was conducted and the results showed that the all the sorbent materials can be used repeatedly without decreasing their adsorption capacity significantly. The neat diammonium salts were also synthesized and interacted with the chorido metal complex anions to form ion-pairs which were then studied for their solubility. The synthesis of the quaternary salts was rather challenging and resulted in some interesting species when impurities of the iodide form of the salts were present in the process of converting them to the iodide form. Some of these include I52+, which was confirmed preliminarily by X-ray structural analysis, potentiometry and cyclic voltammetry. Molecular modeling studies were also conducted to explain the interaction of the chlorido anions with the cationic diammonium centres, and to quantify these interactions by thermodynamic parameters, partial charge calculations, dipole moments and electrostatic potentials, and there was good agreement between theory and experiment. This thesis presents iridium-specific materials that could be applied in solutions of secondary PMGs sources containing rhodium and iridium as well as in feed solutions from ore processing.
4

Separation and integration of the Union power-Concurrently discussion to J.Y.No.585 interpretation

Tseng, Tzu-ming 10 February 2010 (has links)
Separation of powers, the rise of liberalism in eighteenth century and flourished in Europe, it curbs excessive concentration of state power through checks and balances, especially focus on the confrontation between each other. Nowadays it has evolved modern constitution contains two parts: the core components of human rights and the framework of separation of powers. Because the traditional theory of separation of powers derived from the distrust which people have the state power and exercise it. These people oppose the right of any advantage, they often confine to the core areas of power, coupled with the abstract of separation of powers principle itself. They are out of date and can not put forward the best and most functional theories. Also, asking national affairs should be played by the best conditions in all aspects of the sector within the organization, functions and the mode of decisions, and achieve the purpose of suppression of state power. In this paper, we analyzed the explanation and its reason of the petition No. 585 by using the traditional constitutional interpretation method to the new functional interpretation and figurative interpretation to interpret the traditional and fixed separation of powers to dynamic separation of powers. The main core of this paper is to probe into the evolution of our constitutional system. Using our current semi-presidentialism contrasts to the German Weimar Constitution which is one of our constitutional origins and is the prototype of semi-presidentialism. Comparing these two constitutions and try to find out the point and bring up recommendations. The essential of the Constitution in line with people¡¦s basic values and emotions; the content of the Constitution is the social status quo which is never qualified. The theories of separation of powers are methods, it aims to pursuit the union of national consciousness. Truth Investigation Committee exposed the lack of crisis management mechanism of Taiwan's constitutional system, once the constitutional authority doesn¡¦t strictly obey the rules, the Constitution has no solution to handle it! What can the Constitution do to face the lack of self-defense function? When the Constitution still follow the practice to define the authority but the result proceeds in opposite ways with public opinion. The constitution is the political law to safeguard human dignity, and it is futurology which can be pursued its objective of logic and it is interpretable. The rulers of Taiwan all want to control the Constitution but not adhere to it. According to this, we broke the stereotypes and reformulated defense mechanism. Even if we left it unused for a hundred years; perhaps we can provide another level of thinking , and give another solution to unconstitutional review for the future.
5

Equilibrium ²H/¹H fractionations in organic molecules

Wang, Ying. Sessions, Alex L. Rossman, George Robert, January 1900 (has links)
Thesis (Ph. D.) -- California Institute of Technology, 2010. / Title from home page (viewed 03/04/2010). Advisor and committee chair names found in the thesis' metadata record in the digital repository. Includes bibliographical references.
6

Chemical fractionation at environmental interfaces

Cheng, Jie. Hoffmann, Michael R. Seinfeld, John H., January 1900 (has links)
Thesis (Ph. D.) -- California Institute of Technology, 2010. / Title from home page (viewed 03/02/2010). Advisor and committee chair names found in the thesis' metadata record in the digital repository. Includes bibliographical references.
7

Preparation of elemental boron by the Kroll process

Schenk, Robert Cardell, 1937- January 1962 (has links)
No description available.
8

Magnetic separation of strongly magnetic particles using alternating field

Goodluck, Olufemi W. (Olufemi Waheed) January 1986 (has links)
No description available.
9

Vapor-liquid equilibria of n-heptanen-propanol1, chlorobutane system and a theoretical study of gas-solid equilibria

Ashraf, Feroz Ali January 1978 (has links)
No description available.
10

Separation of Fibre and Core from Decorticated Hemp

Parvin, Shahnaz 31 January 2012 (has links)
Separation of fibre from decorticated hemp mixture is important for fibre being use in diverse applications. The main goal of the study was to develop effective and efficient processes to obtain clean hemp fibre. Aerodynamic properties of hemp fibre and core were measured using aerodynamic method to separate fibre and core. Carding method was also used to obtain clean fibre under three different carding durations and five different feeding masses. The third method was the floatation method using water for separating fibre and core. For aerodynamic properties, fibre showed lower terminal velocity and higher drag coefficient than core. The differences in terminal velocity would allow fibres to be separated from core. Using the carding method, the fibre purity was increased from 55% up to 70%. Using the floatation method, the resultant fibre purity ranged from 85 to 90%. Present study discovers some promising methods for hemp fibre cleaning.

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