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THE RECOVERY OF VANADIUM FROM DILUTE ACID SULFATE SOLUTIONS BY RESIN ION EXCHANGE.Zipperian, Donald Charles, 1959- January 1984 (has links)
No description available.
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Comparison of distribution coefficients of 14 elements on three cation exchangersWells, Ricardo Angelo January 2017 (has links)
Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2017. / Certain resins used in ion-exchange separation techniques have become very expensive. Although ion-exchange is an economical method to soften water it is important to keep the cost low during the process. Any exorbitant costs will make a process unattractive and eventually obsolete. Bio-Rad AG MP-50 macroporous resin (supplied by Bio-Rad Laboratories, Ltd.) at present costs approximately R20000 (twenty thousand rand) for 500 g compared to Amberlyst 15 R840.00 for 500 mL and Dowex Marathon MSC R312.34 macroporous resin for 500 mL (both supplied by Dow, Rohm and Haas Co).
This motivated the research to determine by a comparative study if there is any difference in the efficiency and effectiveness in the quantitative analysis of trace elements when these resins are used.
The following elements will be used to determine distribution coefficients for the elements on these resins: Mn, Fe(III), Co, Ni, Cu, Zn, Al, Ag, Cd, In, Ga, Tl, Pb and Bi in 0.1, 0.2, 0.5, 1.0, 2.0, 3.0, 4.0 M nitric acid solutions. Another question is whether there is a difference or a preference when selecting either a microporous or a macroporous resin for the ion-exchange separation. Determination of distribution coefficients for 46 elements had been done by Strelow (Strelow F. W., 1984) in nitric acid on Bio-Rad AG 50W-X8. The results obtained in this study will be compared with the distribution coefficients obtained by Strelow.
The Bio-Rad, Amberlyst and Dowex resins were stirred for approximately 30 minutes in deionised water and then packed in a column. Impurities in the resin column were eluted with 5 M HCl and the resin was then rinsed with deionised water to remove the acid. Thereafter the resins was rinsed out of the column with deionised water, filtered off and then dried under vacuum in an oven at 60 0C for approximately 24 hours. Stock solutions of the elements were prepared as 0.1 M solutions and then diluted with deionised water to obtain solutions having the respective concentrations of 0.1, 0.2, 0.5, 1.0, 2.0, 3.0, and 4.0 M. Quadruplicate reference standards of each element were prepared. Distribution coefficients of the elements on each resin were determined as described by Strelow (Strelow F. W., Distribution coefficients and ion exchange behaviour of some chloride complex forming elements with Bio Rad AG50W - X8 cation exchange resin in mixed Nitric-Hydrochloric acid solutions, 1989).
From the distribution coefficients, obtained from the ICP-OES data, a selectivity series for the 14 elements, mentioned above, was arranged in the decreasing order for each resin’s affinity for the elements. The distribution coefficients also give an indication whether the elements can be quantitatively separated by the cation exchangers in nitric acid media. Elution curves for some elements were done to establish the experimental conditions for quantitative separations of the elements by column cation exchange chromatography.
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Comparative study of brine treatment using a functionalized nanofibre and an ion exchange resinOmoniyi, Emmanuel Oluseyi January 2015 (has links)
Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2015. / In this study, comparative sorption studies of the major metal ions (Mg2+, Ca2+, K+ and Na+) in the brine wastewater were performed on hydrophilic materials (PAN nanofibre, PAN+TiO2 nanofibre, PAN+ZEOLITE nanofibre) and Purolite S950 resin to investigate their uptake performances. For this purpose, PAN nanofibre was electrospun and subsequently doped with 3 wt% each of titanium dioxide and zeolite respectively, in controlled experimental conditions in order to improve its performance. This was followed by the characterization of the respective hydrophilic materials (PAN, PAN+TiO2 and PAN+ZEOLITE nanofibres) using Fourier Transform Infrared Spectroscopy (FT-IR); Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). SEM showed that the incorporation of titanium dioxide or zeolite into the PAN structure made the surface rougher than that of the ordinary PAN nanofibre and FT-IR revealed the peaks belonging to titanium dioxide and zeolite respectively, showing the inorganic materials are within the PAN structure. The XRD analysis complemented the FT-IR of the nanofibres by revealing the peaks characteristic of titanium dioxide and zeolite are present on the PAN structure.
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The synthesis of nitrate-selective resinsChiou, Shang-Jaw, 1948- January 2011 (has links)
Vita. / Digitized by Kansas Correctional Industries
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Simulation and Analyis of a Continuous Variable Cam Phasing Internal Combustion EngineHammarlund, Pär January 2008 (has links)
<p>The development of fuel efficient internal combustion engines (ICE)have resulted in a variety of different solutions. One of those are the variable valve timing and an implemenation of such is the Continuous Variable Cam Phasing (CVCP). This thesis have used a simulation package, psPack, for the simulation of the gas exchange process for an ICE with CVCP. The purpose of the simulations was to investigate what kind of design parameters, e.g. the length of an intake pipe or the duration of combustion, that were significant for the gas exchange process with the alternation of intake pressure, engine speed and valve setting. The parameters that showed a vast impact were those who affected the amount of residual gas and the temperature of the air charge. Furthermore a validation was made between simulation data acquired from psPack and measured data provided in Heywood (1988). The validation showed that for the general behaviour the simulation results from psPack corresponded well to the measured data.</p>
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Magnesium in hemipelagic environments : surface reactions in the sediment-pore water systemvon Breymann, Marta T. 18 November 1987 (has links)
Graduation date: 1988
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Simulation and Analyis of a Continuous Variable Cam Phasing Internal Combustion EngineHammarlund, Pär January 2008 (has links)
The development of fuel efficient internal combustion engines (ICE)have resulted in a variety of different solutions. One of those are the variable valve timing and an implemenation of such is the Continuous Variable Cam Phasing (CVCP). This thesis have used a simulation package, psPack, for the simulation of the gas exchange process for an ICE with CVCP. The purpose of the simulations was to investigate what kind of design parameters, e.g. the length of an intake pipe or the duration of combustion, that were significant for the gas exchange process with the alternation of intake pressure, engine speed and valve setting. The parameters that showed a vast impact were those who affected the amount of residual gas and the temperature of the air charge. Furthermore a validation was made between simulation data acquired from psPack and measured data provided in Heywood (1988). The validation showed that for the general behaviour the simulation results from psPack corresponded well to the measured data.
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Sports sponsorship in Poland: A comparative study of companies’ sponsorship processesCelczynska, Dorota January 2020 (has links)
Sports sponsorship has become a global and multi-billion dollar business. It is an integral part of the company's marketing strategy and viewed as a highly effective form of advertising. Clearly, companies have understood the value of sponsorship for their marketing portfolio and aim to build brand awareness, image, customers’ and employees’ loyalty, and generate higher revenues. However, previous research has shown that the potential of sports sponsorship is still not sufficiently used in Poland. Companies in this country lack knowledge and awareness about the sponsorship of sporting events.The purpose of this study is to analyze differences and similarities between companies' sponsorship processes that sponsor local, national, and international sporting events in Poland. It includes exploring sponsorship promotional activities, objectives, selection criteria, as well as decision-making procedures followed by businesses in the sponsorship exchange process.A qualitative comparative study consisting of 19 interviews with representatives sponsoring sporting events in Poland was used.The results revealed that sponsorship processes vary depending on the level of the sponsored sports event. As the level increases from local to national or international, companies adopt more profit-oriented goals and decisions. Whereas companies sponsoring local sporting events often based their choices on emotions and sympathy to sports disciplines or event organizers. Furthermore, the results also suggested that there is a significant difference between the decision-making procedures of companies involved in sponsoring different levels of sporting events. As the event level rises, it becomes more complex, considered, and longer.In summary, the study shows that companies in Poland recognize event sponsorship as an efficient way to create brand and product image. Although the study also discovers that the role of event sponsorship as a communication tool to achieve commercial goals is not seen by some corporations as a key aspect of strategy.
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De implicita kontrakten : Sjuksköterskors upplevelse av psykologiska kontraktHindi, Dalia, Schilling, Evelina January 2023 (has links)
Title: The implied contracts. Nurses experience of psychological contracts. The purpose of the study was to investigate nurses experience of the psychological contract. An inductive thematic analysis was used where nine semi-structured were conducted with nurses at a hospital in Sweden. The study resulted in six main themes: Clear tasks, Content of the employment relationship, The role of communication, Well-being, Responsiveness and Lack of resources. The working days were regulated by the employment contract, but extra tasks may appear and those were regulated by the psychological contract. The nurses’ expectations in their employment were honesty, responsiveness, and a knowledgeable manager. The communication with the manager was perceived as good, but previous experiences show poor communication. Good well-being in the nurses’ department contributed to the nurses staying, despite considerations about changing employee. They have experienced breach of contract, such as lack of feedback, responsiveness, and broken promises from the employer. They expected more resources such as education and salary. The study can contribute to understand nurturing nurses’ psychological contracts for a functioning employment.
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Development of nitroguanidine wastewater treatment technologiesFields, Marilyn A. January 1985 (has links)
Nitroguanidine (NQ) is a nitramine used in many propellant formulations. The purpose of this study was to develop a method for treating nitroguanidine process wastewaters. The major wastewater contaminants were found to be nitroguanidine and guanidine nitrate (GN) (an intermediate product). Pilot tests were conducted for the removal of nitroguanidine using granulated carbon adsorption (GAC) and ion exchange for the removal of GN. The nitroguanidine concentration in demonstration plant wastewater was reduced from 15.5 mg/L to less than 1 mg/L. The carbon capacity was found to be 0.045 g NQ/g carbon. Strong acid resin was found to reduce guanidinium ion Gu⁺ concentration from 14.5 mg/L to 1 mg/L with a resin capacity of 0.13 eq Gu⁺ /L resin. No significant reduction in resin capacity for Gu⁺ was experienced after five regenerant cycles. A unique two-step regeneration was used. This included a 5% calcium nitrate solution to produce a spent regenerant that could be recycled to the production process. This was followed by regeneration with a 15% sodium chloride solution to place the resin in the sodium form. Anion exchange was used for the removal of nitrate ions. / Master of Science
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