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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.
31

Electrohydrodynamic mixing.

Hoburg, James Frederick January 1975 (has links)
Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / Vita. / Includes bibliographical references. / Ph.D.
32

Multi-scale Statistical Theory And Molecular Simulation Of Electrolyte Solutions

January 2015 (has links)
To clarify the role of ab initio molecular dynamics (AIMD) simulation, this study organizes the McMillan-Mayer (MM) theorem, the potential distribution theorem, and quasi-chemical approach to provide theory for the thermodynamic effects associated with long-length scales. This multi-scale statistical mechanical (MSSM) theory implements quasi-chemical theory after utilizing the MM theorem to integrate-out the solvent degrees of freedom. The MSSM theory treats composition fluctuations which would be accessed by larger-scale calculations, and also long-ranged interactions of special interest for electrolyte solutions. The theory is applied to a primitive electrolyte solution model proposed to investigate ion pairing in the context of tetraethyammonium tetrafluoroborate in propylene carbonate. A Gaussian statistical model is shown to be an effective physical approximation for outer-shell contributions, and they are conclusive for the free energies within the quasi-chemical formulation. Gaussian statistical theory can be more effective than the Bennett numerically exact method when exhaustive sampling is not available, i.e., for finite samples. These results lead to the analysis of the asymptotical behavior of a relative information entropy and thus a new formula for the ion excess free energies. This asymptotic perspective completely avoids the computationally limiting evaluation of the outer-shell contributions. In addition, we use AIMD to obtain the charges on tetramethylammonium and tetrafluoroborate ions contacting neutral and charge carbon nanotube electrodes, and also charges tetraethyammonium and tetrafluoroborate ions in propylene carbonate solution. / acase@tulane.edu
33

Extraction of Metal Values : Thermodynamics of Electrolyte Solutions and Molten Salts Extraction Process

Ge, Xinlei January 2009 (has links)
Over the past centuries, a number of process routes for extraction of metal values from an ore or other resources have been developed. These can generally be classifiedinto pyrometallurgical, hydrometallurgical or electrometallurgical routes. In the caseof the latter two processes, the reaction medium consists of liquid phase electrolytesthat can be aqueous, non-aqueous as well as molten salts. The present dissertationpresents the work carried out with two aspects of the above-mentioned electrolytes.First part is about the electrolyte solutions, which can be used in solvent extractionrelevant to many hydrometallurgical or chemical engineering processes; the secondpart is about the molten salts, which is often used in the electrometallurgical processesfor production of a variety of many kinds of metals or alloys, especially those that arehighly reactive.In the first part of this thesis, the focus is given to the thermodynamics ofelectrolyte solutions. Since the non-ideality of high concentration solution is not wellsolved, a modified three-characteristic-parameter correlation model is proposed,which can calculate the thermodynamic properties of high concentration electrolytesolutions accurately. Model parameters for hundreds of systems are obtained foraqueous as well as non-aqueous solutions. Moreover, a new predictive method tocalculate the freezing point depression, boiling point elevation and vaporizationenthalpy of electrolyte solutions is also proposed. This method has been shown to be agood first approximation for the prediction of these properties.In the second part, a process towards the extraction of metal values from slags,low-grade ores and other oxidic materials such as spent refractories using molten saltsis presented. Firstly, this process is developed for the recovery of Cr, Fe values fromEAF slag as well as chromite ore by using NaCl-KCl salt mixtures in the laboratoryscale. The slags were allowed to react with molten salt mixtures. This extraction stepwas found to be very encouraging in the case of Cr and Fe present in the slags. Byelectrolysis of the molten salt phase, Fe-Cr alloy was found to be deposited on thecathode surface. The method is expected to be applicable even in the case of V, Mnand Mo in the waste slags.Secondly, this process was extended to the extraction of copper/iron from copperore including oxidic and sulfide ores under controlled oxygen partial pressures.Copper or Cu/Fe mixtures could be found on the cathode surface along with theemission of elemental sulphur that was condensed in the cooler regions of the reactor.Thus, the new process offers a potential environmentally friendly process routereducing SO2 emissions.Furthermore, the cyclic voltammetric studies of metal ions(Cr, Fe, Cu, Mg, Mn)in (CaCl2-)NaCl-KCl salt melt were performed to understand the mechanisms, such asthe deposition potential, electrode reactions and diffusion coefficients, etc. In addition,another method using a direct electro-deoxidation concept(FFC Cambridge method),was also investigated for the electrolysis of copper sulfide. Sintered solid porouspellets of copper sulfide Cu2S and Cu2S/FeS were electrolyzed to elemental Cu, S andCu, Fe, S respectively in molten CaCl2-NaCl at 800oC under the protection of Argongas. This direct electrolysis of the sulfide to copper with the emission of elementalsulfur also offers an attractive green process route for the treatment of copper ore. / QC 20100714
34

Electrodialysis in flow injection systems

Hattingh, Cornelius Johannes 04 December 2006 (has links)
Flow injection analysis (FIA) is a continuous flow technique developed in the early 1970's. FIA is based on reproducible sample injection, accurate timing and controlled dispersion. This technique is very versatile due to the control of the variables and can easily be automated. This technique is very suitable for routine laboratory analysis. By introducing various sample modifying techniques in tandem with the FIA system, samples can easily be modified. Some modifying techniques are analyte pre-concentration, sample dilution and sample cleanup. Passive dialysis can be used very successfully for sample dilution and cleanup. Problems arise when samples with low analyte concentration have to be analysed. For this reason an electrodialyser unit, equipped with a passive membrane, was developed. The history, development and theory of membranes and membrane processes are discussed. A study of the movement of ions, in solution and across a passive membrane, under the influence of an applied d.c. electrical potential is given. Passive membranes were evaluated for use in the proposed system. The following factors influencing the efficiency of electrodialysis in the F1 system were studies. The flow rate of the donor and acceptor channels; the applied d.c. electrical potential; injection loop volumes; flow direction in the electrodialyser unit. An investigation was done into on-line analyte pre-concentration and regulated dilution probabilities of the electrodialysis system. Systems that were evaluated are the following: The determination of chloride in water effluents; the determination of copper and zinc in pharmaceuticals; the direct and indirect determination of phosphate in fertilizers. A comparative study between the advantages and disadvantages of the passive dialysis and electrodialysis system is given. / Thesis (PhD (Chemistry))--University of Pretoria, 2006. / Chemistry / unrestricted
35

Effect of Protein Charge and Charge Distribution on Protein-Based Complex Coacervates

Kapelner, Rachel A. January 2021 (has links)
Polyelectrolytes of opposite charge in aqueous solution can undergo a liquid-liquid phase separation known as complex coacervation. Complex coacervation of ampholytic proteins with oppositely charged polyelectrolytes is of increasing interest as it results in a protein rich phase that has potential applications in food science, protein therapeutics, protein purification, and biocatalysis. However, many globular proteins do not phase separate when mixed with an oppositely charged polyelectrolyte, and those that do phase separate do so over narrow concentration, pH, and ionic strength ranges. Much of the work that has been done on complex coacervates looks at polymer-polymer systems. While there have been some initial studies showing that proteins can undergo complex coacervation, the major design factor studied to date has been overall protein charge. The tools of genetic engineering, which allow the precise tuning and placement of charge have not been used to more fully understand the design criteria for protein complex coacervation. In this dissertation, we developed a model protein library based on green fluorescent protein (GFP) to study the impact of protein net charge and charge distribution on protein phase separation with polyelectrolytes. We developed a short, ionic polypeptide sequence (6-18 amino acids) that can drive the liquid-liquid phase separation of globular proteins. We characterize the phase behavior of the protein library with a homopolymer and diblock copolymer of similar chemistry to elucidate how protein design impacts macro- and microphase separation. In these phase characterization studies, differences in the nature of phase separation as well as the salt stability of the protein coacervates with the different polymer species are identified. We finally used this model protein library to study the effects of the protein design and phase separation behavior for coacervate-based applications including intracellular protein delivery, purification, and protein stabilization.
36

A compatibility profile of selected therapeutic agents in balanced electrolyte solutions

Tozlian, Harry Michael 01 January 1975 (has links)
Through the years, various studies (1-5) have been done regarding the prevalent practice of adding one or more drugs to parenteral fluids. The greater variety of drugs being used intravenously, plus the formulation of newer and more complex parenteral fluids, has led to an increased awareness of potential incompatibilities existing between drug and solution. Recognition of the hazards of such extemporaneous combinations has necessitated the study of drug stability in solution. The objective of this report is to determine compatibility characteristics of admixtures prepared from a series of balance intravenous electrolyte solutions and a group of commonly used therapeutic agents. Visual, spectrophotometric and microbiological assay techniques are to be used to establish the compatibility profiles of these admixtures.
37

Estimations of the effective electrolytic surface area of rough and porous silver electrodes ; II. Potentiostatic oxidation of silver in alkaline electrolyte

Bearss, James Glenn 01 August 1969 (has links)
This dissertation is written in two sections. The first section deals with the development of methods for the estimation of the effective electrolytic surface area of rough and porous silver electrodes in alkaline electrolyte. Data are presented comparing the results of three different methods of surface area estimation. Model pore electrodes were also prepared and oxidized to study the reactions in a pore. Data for constant current oxidations of these electrodes is given. The second section deals with the potentiostatic oxidations of silver in alkaline electrolyte. Data are presented on the total charge acceptance versus applied potential for a potential range that runs from the potential required to first produce silver (I) oxide to that required to evolve oxygen off the surface of the electrode. The shape of this plot indicates the formation of two types of silver (I) oxide. Three oxidation reactions were noted. The first was the formation of silver (I) oxide. The second was the formation of silver (II) oxide. The nature of the third reaction is not yet known; however, some evidence indicates it is the formation of silver (III) oxide.
38

Effects of protein in carbohydrate-electrolyte solutions on post-exercise rehydration / CUHK electronic theses & dissertations collection

January 2014 (has links)
This thesis aimed to, first, examine the effects of the addition of whey protein or casein protein to common carbohydrate-electrolyte (CE) solutions on post-exercise rehydration; second, examine the effects of various contents of whey protein in CE solutions on post-exercise rehydration; and third, investigate the mechanisms on the increased fluid retention after the ingestion of CE plus whey protein solutions. / The first study (Chapter 4) of this thesis examined the effects of CE solution added with a certain amount of whey or casein protein on post-exercise rehydration. Ten young healthy males (mean ± SEM, age: 20.7 ± 0.4 years; body weight (BW): 65.4 ± 2.0 kg; maximal oxygen uptake (VO₂ₘₐₓ): 60.7 ± 1.9 mL·kg⁻¹·min⁻¹) were recruited in this study. Three main experimental trials were conducted in a randomized single-blinded crossover design and separated by at least 7 days between any two of them. In each main trial, subjects ran for 60 min at 65% VO₂ₘₐₓ on a treadmill in a warm and humid environment (24 °C, 60% relative humidity (RH)), which was followed by a 4-hour recovery period. During recovery, the subjects were provided with either a common CE solution, or a CE with whey protein (CW) solution, or a CE with casein protein (CC) solution. The three solutions were matched for energy and electrolyte content and were provided in six equivalent volumes at 30 min intervals with a total volume equivalent to 150% of their BW loss. The nude BW, urine samples, and capillary blood samples were collected before and after exercise and at the end of each hour during recovery. After exercise, the subjects lost approximately 2.3% of their pre-exercise BW in all trials. Total urine volume after recovery was higher in the CE and CC trials than in the CW trial (CE vs. CW vs. CC: 1184 ± 120 mL vs. 1005 ± 68 mL vs. 1256 ± 130 mL, p < 0.05), which induced greater fluid retention in CW trial compared with both CE and CC trials (CE vs. CW vs. CC: 46.9 ± 5.2% vs. 54.9 ± 2.9% vs. 45.8 ± 5.5%, p < 0.05). By the end of recovery, the urine specific gravity (USG) was lower in the CE trial than in both CW and CC trials (CE vs. CW vs. CC: 1.002 ± 0.001 g·mL⁻¹ vs. 1.004 ± 0.001 g·mL⁻¹ vs. 1.004 ± 0.000 g·mL⁻¹, p < 0.05). In addition, the urine osmolality was lower in the CE trial than in both CW and CC trials after recovery (CE vs. CW vs. CC: 111 ± 18 mmol·kg⁻¹ vs. 181 ± 14 mmol·kg⁻¹ vs. 195 ± 23 mmol·kg⁻¹, p < 0.05). However, no difference was found in the changes of plasma volume among trials throughout recovery. These results suggested that during a 4-hour recovery after 60 min run which induced about 2% BW loss, the CE plus whey protein solution was more effective in fluid retention compared with the isocaloric CE or CE plus casein protein solution. / The second study (Chapter 5) was conducted to examine the effects of various contents of whey protein in CE solutions on post-exercise rehydration; meanwhile, the mechanisms on the greater fluid retention after the ingestion of CE plus whey protein solutions were investigated as well. Ten young healthy males (mean ± SEM, age: 22.0 ± 0.7 years; BW: 64.5 ± 1.9 kg; VO₂ₘₐₓ: 59.8 ± 1.9 mL·kg⁻¹·min⁻¹) finished five main experimental trials in a randomized single-blinded crossover manner and separated by at least 7 days. After a 60-min run at 65% VO₂ₘₐₓ on a treadmill in each main trial, a 4-hour recovery period was carried out. During recovery, five solutions of 1) a CE solution with high CHO content (CE-H); 2) a CE solution with low CHO content (CE-L); 3) a CE solution with high content of whey protein (CW-H); 4) a CE solution with medium content of whey protein (CW-M); and 5) a CE solution with low content of whey protein (CW-L) were consumed by the subjects randomly. The electrolyte content was matched, whereas CE-H, CW-H, CW-M, and CW-L solutions were matched for energy density, CE-L and CW-H solutions were matched for CHO content. The total volume consumed by subjects was 150% of the BW loss, and the solutions were provided in six equal volumes at 30 min intervals during recovery. The nude BW, urine samples, and capillary and venous blood samples were obtained before and after exercise and at the end of each hour during recovery. The results showed that the subjects lost about 2.2% of BW after exercise. By the end of the recovery, the total urine volume was smaller in the CW-M trial than in the CE-H trial (CE-H vs. CW-M: 1295 ± 103 mL vs. 1049 ± 130 mL, p < 0.05), whereas the CW-H trial was smaller than the CE-H, CE-L, and CW-L trials (CE-H vs. CE-L vs. CW-L vs. CW-H: 1295 ± 1033 mL vs. 1284 ± 90 mL vs. 1141 ± 58 mL vs. 891 ± 73 mL, p < 0.01). The less urine production in the CW-M and CW-H trials resulted in a greater fluid retention compared with CE-H, CE-L, and CW-L trials (CE-H vs. CE-L vs. CW-L vs. CW-M vs. CW-H: 38.4 ± 5.2% vs. 36.1 ± 4.3% vs. 43.0 ± 3.8% vs. 51.0 ± 5.7% vs. 55.4 ± 3.8%, p < 0.05). The CE-H and CE-L trials showed lower USG and urine osmolality compared with the CW-L, CW-M, and CW-H trials at the end of recovery (p < 0.05). In addition, the plasma osmolality of the CE-L trial was lower than that of the CW-L, CW-M, and CW-H trials at the 1st hour of recovery (CE-L vs. CW-L vs. CW-M vs. CW-H: 274 ± 4 mmol·kg⁻¹ vs. 291 ± 4 mmol·kg⁻¹ vs. 301 ± 6 mmol·kg⁻¹ vs. 293 ± 6 mmol·kg⁻¹, p < 0.05). The plasma volume was lower in the CE-L trial than that in the CW-H trial at the 2nd and 3rd hour, and the CE-L trial reached the lowest plasma volume than the other four trials by the end of recovery (p < 0.05). The aldosterone concentration was lower in both CE-H and CE-L trials compared with the CW-M and CW-H trials after recovery (CE-H vs. CE-L vs. CW-M vs. CW-H: 228 ± 100 pg·mL⁻¹ vs. 211 ± 51 pg·mL⁻¹ vs. 336 ± 85 pg·mL⁻¹ vs. 333 ± 70 pg·mL⁻¹, p < 0.05). The antidiuretic hormone (ADH) concentration was also found to be lower in the CE-L trial than in the CW-H trial at the 1st and 2nd hour of recovery (p < 0.05). However, no difference was found in plasma albumin concentrations among trials throughout recovery. The results indicated that the CE solutions with higher whey protein content retained more fluid compared with CE solutions with lower whey protein content or CE solution alone. The greater fluid retention was partly caused by the elevated aldosterone concentrations in the situations of current study. / In summary, the experimental results of this thesis found that the consumption of common CE solution plus whey protein can retain more fluid in body than isocaloric CE or CE plus casein protein solution during post-exercise recovery. CE solutions with relative higher whey protein content were more effective in fluid retention than CE solutions with lower whey protein content. Furthermore, the additive effects on fluid retention caused by whey protein supplementation were induced by the increased concentrations of plasma aldosterone. The elevated plasma osmolality and ADH concentrations maybe also played a role in the greater fluid retention. However, further studies are needed to clarify this issue. The current findings provided more evidences in this research topic and suggested some recommendations to athletes and sports enthusiasts to reach rehydration rapidly and effectively after exercise. / 本論文的研究目的包括:首先,研究在普通的碳水化合物-電解質(CE)飲料中添加乳清蛋白或酪蛋白對運動後復水的影響;其次,研究CE飲料中添加不同劑量的乳清蛋白對運動後復水的影響;再次,闡述飲用CE加乳清蛋白飲料後更能有效的將水分保留在人體內的機制。 / 實驗一(第四章)研究了在CE飲料中加入一定劑量的乳清蛋白或酪蛋白對運動後復水的影響。十位年輕、健康男性受試者(平均值 ± 標準誤,年齡: 20.7 ± 0.4 歲;體重: 65.4 ± 2.0 千克;最大攝氧量: 60.7 ± 1.9 mL·kg⁻¹·min⁻¹)自願參加本項測試。按照隨機單肓交叉設計,他們完成了三次主測試,期中任何兩次測試時間都相隔七天以上。在每一次主測試中,受試者首先在跑臺上以65%最大攝氧量的運動強度完成了60分鐘的跑步運動(運動環境控制在24攝氏度,60%相對濕度),隨後開始4小時的運動後恢復階段。在恢復過程中,受試者會分別飲用三種不同飲料中的一種。三種飲料包括:(1)普通CE飲料(CE組);(2)普通CE飲料中添加乳清蛋白(CW 組);(3)普通CE飲料中添加酪蛋白(CC 組)。三種飲料含有相同的能量密度及電解質濃度。受試者在每次主測試中飲用的總飲料體積為1.5倍的體重減少量,這些飲料分為6等份并每隔30分鐘由受試者飲用一份。運動前、後及在恢復階段每隔一小時收集受試者的體重(裸重)、尿液樣本、及血液樣本(指尖取血)。在三次主測試中,受試者在運動結束後減少的體重量約為運動前體重的2.3%。在4小時的恢復階段中,CE組和CC組受試者排出的尿液總體積大於CW組(CE vs. CW vs. CC: 1184 ± 120 mL vs. 1005 ± 68 mL vs. 1256 ± 130 mL, p < 0.05)。所以,恢復結束後,CW組的水分保持比例高於CE組及CC組(CE vs. CW vs. CC:46.9 ± 5.2% vs. 54.9 ± 2.9% vs. 45.8 ± 5.5%, p < 0.05)。在恢復結束時,CE組的尿比重低於CW組及CC組(CE vs. CW vs. CC: 1.002 ± 0.001 g·mL⁻¹ vs. 1.004 ± 0.001g·mL⁻¹ vs. 1.004 ± 0.000 g·mL⁻¹, p < 0.05)。另外,在恢復結束後,CE組尿滲透壓水平低於CW組及CC組(CE vs. CW vs. CC: 111 ± 18 mmol·kg⁻¹ vs. 181 ± 14mmol·kg⁻¹ vs. 195 ± 23 mmol·kg⁻¹, p < 0.05)。但是,在恢復階段,血漿容量的變化在三組中沒有顯著差異。本實驗的結果表明,完成60分鐘跑步後,受試者丟失掉約2%的體重,在之後4小時恢復階段中,飲用添加乳清蛋白的CE飲料比有相同能量密度的普通CE飲料或添加酪蛋白的CE飲料更能有效的將水分保留在體內。 / 實驗二(第五章)研究了在普通CE飲料中添加不同劑量的乳清蛋白對運動後復水的影響;同時,也研究了飲用CE加乳清蛋白飲料後更能有效的將水分保留在人體內的機制。十位年輕、健康男性受試者(平均值 ± 標準誤,年齡: 22.0 ± 0.7 歲;體重: 64.5 ± 1.9 千克;最大攝氧量: 59.8 ± 1.9 mL·kg⁻¹·min⁻¹)自願參加本項測試。按照隨機單肓交叉設計,他們完成了五次主測試,任何兩次測試的時間都相隔七天以上。在每一次主測試中,受試者首先在跑臺上以65%最大攝氧量的運動強度完成了60 分鐘的跑步運動,隨後開始4 小時的運動後恢復階段。在恢復過程中,受試者會飲用五種不同飲料中的一種。五種飲料包括:(1)普通CE飲料,含有較高的CHO濃度(CE-H組);(2)普通CE飲料,含有較低的CHO濃度(CE-L組);(3)普通CE飲料添加較高劑量的乳清蛋白(CW-H組);(4)普通CE飲料添加中等劑量的乳清蛋白(CW-M組);(5)普通CE飲料添加較低劑量的乳清蛋白(CW-L組)。五種飲料含有相同濃度的電解質,其中,CE-H,CW-H,CW-M,及CW-L組有相同的能量密度,CE-L 及CW-H 組有相同的CHO含量。在每次主測試的恢復階段,受試者飲用的飲料總體積為1.5倍的體重減少量,這些飲料分為6等份并每隔30分鐘由受試者飲用一份。運動前、後及在恢復階段每隔一小時收集受試者的體重(裸重)、尿液樣本、及血液樣本(指尖取血及靜脈取血)。運動結束後,受試者的體重減少量約為運動前體重的2.2%,五組測試中沒有顯著差異。在4小時的恢復階段後,CW-M 組受試者的尿液總體積小於CE-H組(CE-H vs. CW-M:1295 ± 103 mL vs. 1049 ± 130 mL, p < 0.05);同時,CW-H組的尿量低於CE-H,CE-L,及CW-L組(CE-H vs. CE-L vs. CW-L vs. CW-H: 1295 ± 103 mL vs. 1284 ± 90mL vs. 1141 ± 58 mL vs. 891 ± 73 mL, p < 0.01)。相對於CE-H,CE-L,及CW-L組,較少的尿液排出量使CW-M及CW-H組能將更多的水分保留在體內(CE-H vs.CE-L vs. CW-L vs. CW-M vs. CW-H: 38.4 ± 5.2% vs. 36.1 ± 4.3% vs. 43.0 ± 3.8% vs.51.0 ± 5.7% vs. 55.4 ± 3.8%, p < 0.05)。在恢復結束後,CE-H及CE-L組的尿比重水平及尿滲透壓水平低於CW-L,CW-M,及CW-H組(p < 0.05)。另外,在恢復階段的第1小時,CE-L組的血漿滲透壓水平低於CW-L,CW-M,及CW-H組(CE-L vs. CW-L vs. CW-M vs. CW-H: 274 ± 4 mmol·kg⁻¹ vs. 291 ± 4 mmol·kg⁻¹ vs. 301 ± 6 mmol·kg⁻¹ vs. 293 ± 6 mmol·kg⁻¹, p < 0.05)。在恢復階段的第2及3小時,CE-L組的血漿容量低於CW-H組;在恢復結束時,CE-L組的血漿容量低於其它四組(p <0.05)。對于兩種體液平衡調節激素,在恢復結束時,CE-H及CE-L組的醛固酮水平低於CW-M及CW-H組(CE-H vs. CE-L vs. CW-M vs. CW-H: 228 ± 100 pg·mL⁻¹ vs. 211 ± 51 pg·mL⁻¹ vs. 336 ± 85 pg·mL⁻¹ vs. 333 ± 70 pg·mL⁻¹, p < 0.05)。在恢復階段的第1及2小時,CE-L組的抗利尿激素水平低於CW-H組(p < 0.05)。然而,五組測試中,血漿白蛋白水平在恢復階段沒有顯著差異。本實驗的研究結果表明,普通CE飲料中加入較高劑量的乳清蛋白比較低劑量的乳清蛋白更能有效的將水分保留在人體內。這種較高水平的水分保留能力與醛固酮激素水平的升高有關。 / 綜上所述,本論文的研究結果發現,在運動後的恢復階段飲用添加乳清蛋白的CE飲料比有相同能量密度的普通CE飲料或添加酪蛋白的CE飲料更能有效的將水分保留在人體內。並且,在CE飲料中加入較高劑量的乳清蛋白比較低劑量的乳清蛋白對人體內水分的保留更加有效。另外,這種較高水平的水分保留能力是由醛固酮激素水平的升高引起的。同時,較高的血漿滲透壓及抗利尿激素水平可能對這種高效的水分保留能力也有一定的促進作用,但需要更多的研究來闡述這一觀點。本論文的研究結果為運動後復水的相關研究提供了更多的理論證據,並且對運動員及運動愛好者在運動結束後如何進行快速有效的復水提出了指導及建議。 / Li, Liang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 131-149). / Abstracts also in Chinese; appendixes includes Chinese. / Title from PDF title page (viewed on 01, November, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.
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Modélisation et simulation des systèmes électrolytiques multiphasiques réactifs dans l’environnement ProSim : Application aux géo-ressources / Modeling and simulation of multiphase reactive electrolyte systems in the ProSim environment : applications to geo resources

Pouget, Clémentine 20 October 2017 (has links)
La simulation des procédés est un outil de développement, de dimensionnement et d’optimisation des procédés dans les industries chimiques, pétrochimiques, pharmaceutiques, alimentaires, de l’énergie ou du traitement de gaz. Elle fournit une représentation des opérations du procédé en utilisant des modèles mathématiques pour chaque opération unitaire, s’assurant du respect des bilans de matière et d’énergie. Cependant l’utilisation de la simulation des procédés dans l’industrie peut être limitée par un manque de connaissance en thermodynamique.L’étude réalisée dans le cadre de cette thèse a pour objectif d’enrichir les modèles thermodynamiques adaptés aux solutions électrolytiques des logiciels de ProSim® avec les compétences du LaTEP dans le cadre d’applications aux géo-ressources et en profitant de la modélisation des opérations unitaires déjà présentes dans les logiciels de ProSim®.Dans un premier temps, les concepts et les définitions de base de la thermodynamique des solutions, nécessaires au développement des modèles, et notamment du cas particulier des solutions électrolytiques seront présentés, aboutissant sur l’écriture des divers équilibres permettant de décrire les solutions électrolytiques.Puis les grands principes des différents modèles thermodynamiques nécessaires à l’écriture des équilibres des solutions électrolytiques seront présentés, en mettant l’accent sur les modèles de coefficient d’activité qui sont alors spécifiques aux modèles électrolytiques prenant en compte les interactions de longue portée engendrées par la présence d’ions.Enfin, trois cas d’études de systèmes électrolytiques multiphasiques réactifs appliqués aux géo-ressources sont examinés : la géothermie profonde ; le traitement de gaz acides, issus de fumées de l'oxy-combustion d’une centrale à charbon ; la récupération du lithium. / Chemical process simulation is a very useful tool to improve the development, design and optimization of processes. Then, it can help in the chemical, petrochemical, pharmaceutical, energy production, gas processing, environmental, and food industries. It provides a representation of the operations of the process using mathematical models for the different unit operations, ensuring that mass and energy balances are satisfied. However, the use of process simulation in industry is currently being limited by a lack of understanding of thermodynamics.
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NMR-Untersuchungen zur kollektiven Diffusion von Wasser und gelösten Ionen: Die dynamische Hydratationszahl und der Einfluss poröser Materialien

Beckert, Steffen 22 July 2013 (has links) (PDF)
Gegenstand der Arbeit ist die Untersuchung der kollektiven Diffusion von Wasser und Ionen in wässrigen Elektrolytlösungen. Dabei wird insbesondere die Dynamik der Wassermoleküle innerhalb der Hydratationshüllen der Ionen und der Einfluss poröser Materialien untersucht. Nach einer Einführung zur Dynamik der Hydratationshülle folgen Grundlagen der NMR-Diffusometrie, welche genutzt wurde um die Selbstdiffusionskoefifizienten der Wassermoleküle und der Ionen der Lösungen zu messen. Daraus wurden die dynamischen Hydratationszahlen der Ionen bestimmt, welche die Anzahl an Wassermolekülen angeben, die durch die Diffusion des Ions in ihrer translatorischen Bewegung beeinflusst sind. Der Einfluss poröser Materialien auf die Dynamik wird am Beispiel nanoporöser Glasmonolithe und mikroporöser Li-LSX Kristalle untersucht.

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