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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.
411

Research of using tide-type bioreactor to culture CHO cells / 利用潮汐式生物反應器培養中國倉鼠卵巢(CHO)細胞之研究

Kai-Li Lin, 林凱理 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 / In this study, we mainly discussed that using tide-type bioreactor to culture CHOβ-gal 37 cell lines which could expressβ-gala- ctosidase and probe into that serum concentration and additives make what effect upon the production. In the experiment of stationary culture, we have cultured plenty of CHOβ-gal 37 cells and preserved them successfully. The effect of serum concentration on cell growth, CHO cells cultured in IMDM media with 5% FBS grew faster and produce moreβ-gal. To probe into the effect of additives on cell growth, adding 2.4g/L peptone in serum-low media could enhance the growth of CHO cells, but could not raise the production of β-gal. The growth rate of CHO cells treated with 1% DMSO decreased gradually with increase in specific activity. Therefore, the best scheme in stationary culture is that culturing CHO cells in serum-low media without DMSO, and then replacing media with DMSO at fourth day. In the aspect of bioreactor culturing, we have successfully cultivated CHO cells in tide-type bioreactor. When cells grew below the liquid surface in bioreactor, the number of cells could arrive above 2.5 x 106 cells. Furthermore, we observed that vertical moving of air-water interface would result negative effect on cell growth in tide range. Tide-type bioreactor could be considered an ideal bioreactor because it is easily operated and have a low shear force, bubble-free condition for cell culture. In future prospection, we would probe into the decided mechanism of DMSO and find out better substitutes of serum. In tide-type bioreactor, we want to improve tide-type bioreactor on culturing cells efficiently and study the reason of inhibition of cell growth in tide range or to prevent this phenomenon.
412

Phase equilibria and solidification properties of the ternary Sn-Cu-Ni alloys / 錫-銅-鎳三元合金之相平衡與固化性質

Chih-Hao Lin, 林志豪 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 /
413

利用Saccharomycescerevisiae進行ethyl4-chloroacetoacetate不齊還原反應系統之動力學研究

Jia Sheng Liau, 廖家聖 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 / Kinetic analysis and modeling for asymmetric reduction of ethyl-4- chloroacetoacetate to produce S-4-chloro-3-hydroxybutanoic acid ethyl ester catalyzed by Saccharomyces cerevisiae was conducted. The effect of temperature and pH on the activity and the stability of the biocatalyst were examined. The change of the kinetic behavior when XAD 2 resin was added to the reaction solution was also investigated. When the substrate concentration was 73.5 mM, relative high product’s optical purity (87.5% ee) and reaction yield (74.5%) were obtained at 30℃, pH 8.5. A significant decomposition effect for substrate in the reaction solution without yeast cells was observed. At the operation condition, the substrate hydrolysis rate constant was determined as 8.31×10-5 min-1.51.mM-1.51 and the reaction followed a 2.51-order kinetics. On the other hand, the product could exist steadily in the reaction solution. A substrate inhibition was found in this biocatalytic reaction, while no product inhibition was observed. From the initial rate data obtained from the experiments performed at different initial substrate concentrations, Lineweaver-Burk plot, Hanes plot and Eadie-Hofstee plot techniques were used to determine the values of the apparent kinetic parameters. The Km, Ki and vm were estimated to be 17.84 mM, 193.76 mM and 11.66 mM/g cell min, respectively. In addition, the apparent Km, Ki and vm for the S-enzymes in S. cerevisiae cells were estimated to be 29.00 mM, 119.23 mM and 12.41 mM/g cell min, respectively. The apparent Km, Ki and vm for the R-enzymes were estimated to be 35.91 mM, 96.29 mM and 0.9 mM/g cell min, respectively. Under the simultaneous consideration of the effects of substrate inhibition and substrate hydrolysis, a kinetic model for describing the apparent reaction behavior was established. The good consistency between the experimental data and the theoretically predicted values verifies that the proposed model can successfully simulate the behavior of this reaction. Finally, the supplement of XAD 2 resin could effectively reduce the substrate inhibition effect. The reaction yield and the product’s ee could also be enhanced.
414

Conductive Behavior of Lithium Ions in Polyacrylonitrile-based Gel Polymer Electrolyte Containing Non-solvent / 鋰離子在含非溶劑之PAN系膠態高分子電解質中傳導行為之研究

Cheng-Liang Cheng, 鄭丞良 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 /
415

氟系印刷電路板材料的性質研究

林雪貞 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 /
416

Study of Co-doped Y1-xSrxMnO3 as a cathode for solid oxide fuel cell / 以Co-dopedY1-xSrxMnO3為固態氧化物燃料電池陰極材料之研究

黃璟瓔 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 /
417

Heat dissapation behavior of lithium-ion battery / 大型鋰離子電池散熱行為之研究

Gui-hong liu, 劉桂宏 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 /
418

Study on Thermoplastic Polymer Modified Novolac Type Epoxy Resin Derived Carbon/Carbon Composite / 熱塑性樹脂改質環氧樹脂基材製備碳/碳複合材料之加工製程參數及性質研究

Chih-Yuan Chen, 陳致源 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 / In this study, modified novolac type epoxy resin has been used as a new matrix precursor to fabricate C/C composites. The polydimethylsiloxane polyurethane synthesized was used as a modification agent. Novolac type epoxy has almost the same chemical structure as phenolic resin, however, it possesses the epoxied functional group that is easy to react with the modification agent. The modification system utilized is polydimethylsiloxane polyurethane(PDMS-PU) which protects the fiber surface and improves the thermal stability of matrix. PDMS-PU was synthesized in this study and it structure was confirmed by IR and NMR. Results show that modified epoxy with low content(<10phr) of PDMS-PU is miscible, the PDMS-PU can completely disperse in the epoxy matrix and decrease the glass transition temperature and crystallinity of novolac type epoxy. In the study of curing kinetics, it was found that the content of PDMS-PU will affect the collision factor, total heat of reaction and the active energy of reaction. In order to achieve the modification purpose, the first step is utilizing novolac type epoxy resin to derive carbon/carbon composite instead of using phenolic resin. Different post curing times and temperatures, and different carbonization heat treatment temperatures were applied to the novolac type epoxy resin. Results show that the matrix cured at a higher post-curing time and temperature exhibits a significantly weight loss on the post curing process and limits the weight loss on carbonization processing. In the modified composite system, results show that the flexural strength of composite after post curing process will be reduced when the PDMS-PU content increase because of the flexible molecular structure. In the carbonization process, PDMS-PU will protect the fiber surface to prevent the intense shrinkage deriving from thermal degradation consequently, increase the flexural strength of C/C composite from 94.2Mpa to 106.9MPa after carbonization process. Oxidation testing result shows that PDMS-PU containing carbon/carbon composites exhibit better oxidation resistance and lower oxidation rate than those derived from pure epoxy resins. Increasing the post-cure time and temperature will improve the mechanical properties after carbonization. In the carbonization process, the mechanical properties and density decrease rapidly after 400℃. When heat treatment temperature rises up to 800℃ the mechanical properties and density will maintain constant and then increasing slightly. The mechanical property of the carbon/carbon composite made by epoxy resin was better than that of phenolic resin, and the flexural of composite strength was increased from 63.9MPa to 94.2Mpa.
419

Cultivation of Chlorella NC64A with Virus PBCV-1 Infection for Hyaluronic Acid Production. / 綠藻NC64A之培養及其透明質酸之生產

Jeng-Long Sheu, 許正隆 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 / The energy on the Earth is relatively limited. Therefore, in recent years everybody pay attention to the application and development of renewable resource gradually. Microalga that have a wide range of application are renewable resource. The biomass of microalga include abundant protein, vitamin and other materials that can provide to increase in the food, animal feed, medicine, health care food etc. Easier cultivation and faster growth would the advantage of microalga. Besides, microalga had the special features that never compete in farming ground with traditional farm crop. This research would aim at the heterotrophic cultivation of Chlorella NC64A with virus PBCV-1 infection for hyaluronic acid production. In the result of our experiment, we discovered that NC64A could cultivate in high cell density with heterotrophic conditions and the cell number was 3×108 cells/L. Compare heterotrophic with autotrophic NC64A, the cell concentration of former could reach 55 times of the latter. The high concentration NC64A were infected with virus PBCV-1(m.o.i.: 0.0014) in 24hours. The molecular weight and concentration of hyaluronic acid, collected from Chlorella NC64A, were 1.6×106 Da and 12.6 mg/L-broth respectively. We observed a phenomenon that Chlorella NC64A would been inhibited by an unclear mechanism when EDTA and monosaccharide were exist in the medium at the same time. In addition, the weight percentage of algae cell triglyceride(TG) has risen to 11% of dry cell weight when alga cultured with MSG as nitrogen source of medium. In the future, this research would intend and continue the directions of proceeding: (1) Increase the cell concentration of NC64A continuously by using the strategy of fed- batch carbon source. (2) Culture algae cell with organic wastes to low the production cost. (3) Rise the TG content of algae cells with the biphasic strategy. (4) Study the effect upon the production of hyaluronic acid under using different infection conditions. (5) Try to understand that how EDTA and monosaccharide induce the inhibition of NC64A growth.
420

Nano-Scaled Crystallization Behavior of Block Copolymers:Isothermal Crystallization Kinetics and Crystallization induced Morphological Transition / 團聯式共聚合體之奈米空間結晶行為研究:等溫結晶動力學與結晶誘導形態轉換

Ja-Chi Wu, 吳家齊 January 2001 (has links)
碩士 / 國立清華大學 / 化學工程學系 / 89 / Abstract The morphology and crystallization kinetics in the blends of a symmetric poly(ethylene oxide)-block-polybutadiene (PEO-b-PB) and a PB homopolymer were investigated by small angle X-ray scattering (SAXS) and DSC. In the melt state, morphological transition from lamellae to hexagonally packed cylinders to bcc packed spheres was observed with increasing volume fraction of PB (|PB). The crystallization kinetics of PEO blocks confined in the nano-scaled microdomains exhibited a parallel transition with the morphological transformation. The distinct correlation was largely associated with the homogeneous nucleation-controlled crystallization in the microdomains, where the proportionality between nucleation rate and microdomain volume rendered the basis for the direct correlation. The crystallization was homogeneous nucleation controlled since impurities were unable to be induced nucleation in the nano-scaled microdomains. The homogeneous nucleation controlled mechanism was further verified the by first-order kinetic behavior associated with the cryatallinity development. In this case, the crystal kinetics in the lamellar melt was however not HN controlled. The crystallization rate decreased slightly as |PB increased because the crystallization behavior was not only dominated by nucleation but also influenced by crystal growth since the crystal growth was capable of propagating over a macroscopic length scale. The morphology of blends after crystallization was also detected by SAXS and it was also found that the initial microdomain structure was neither fully preserved nor completely disrupted into 1-D stacked lamellar morphology upon crystallization. An "intermediate structure" was likely formed after the crystallization.

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