Дисертації з теми "Pure compounds"
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1
Harvey, Ian. "Applications of enzymatic methods to the preparation of enantiomerically pure compounds." Thesis, University of Warwick, 1989. http://wrap.warwick.ac.uk/106588/.
Анотація:
This thesis describes investigations in the field of biotransformations, concentrating on the mode of action of esterases and lipases, and the application of these systems to the production of enantiomerically pure compounds. The behaviour of pig liver esterase (PLE) in the presence of some commonly use alcohol and ketone cosolvents was examined. Methanol, ethanol and 2-butanone were found to be potent inhibitors of PLE. At low concentrations, acetone accelerated the rata of PLE catalysed hydrolysis, but is also inhibitory at higher concentrations. The effects of alcohols as product inhibitors were examined. This, and other data obtained suggests that the complex kinetics of this enzyme could be explained using the 'Ligand Induced Slow Transition Model" (Ainslie et al., J. Biol. Cham., 1972, 247, 7088). Examination of PLE by gel filtration hplc suggested that the active form of this enzyme may not be trimeric as previously thought. Soma analogous studies were carried out with pig pancreatic lipase. The use of the isosyme-specific inhibitors, eserine and phenylmethylsulfonyl fluoride did not improve the enantiospecificity of the hydrolysis of trans-1,2-diacetoxy-cyclopentane catalysed by PLE. Dimethyl mono-3-cyclobutene-1,2-dicarboxylate was hydrolysed to the corresponding mono-ester by pig liver esterase with high optical purity (56% a.e.) and chemical yield. The mono-ester epimerised during derivatisation mediated by 1,1-carbonyldiimidazole, allowing the preparation of optically pure trans derivatives. Rapid derivatisation allowed the preparation of cis analogues. This was demonstrated by the preparation of both the optically pure cis and trans benzylamide derivatives. Mono-3-Cyclobutane-1.2-dimethanol diacetate was hydrolysed to the corresponding mono-acetate by Pseudomonas fluorescene lipase with high optical purity (>97% a.e. at 0.8 mol-equivalent) and chemical yield. The corresponding (4-phenyl)benzoyl, (4-toluene)sulphonyl and (4-phenylethene-9-yl) derivatives were prepared. The racemic allene diethyl penta-2,3-dismodicate was hydrolysed by pig liver esterase in buffer containing 232 (v/v) acetone. The product, (g)-(-)-ethyl penta-2,3-dismodicate, was produced with 30 – 33% a.e. at 0.3 mol-equivalents. As a demonstration of the development of a hydrolytic resolution procedure, such a method was devised for the preparation of an optically pure halogenated propan-l-el derivative. Pig pancreatic lipase was chosen as the model system. By manipulating the reaction conditions and the acid moiety, the enantiospecificity of the hydrolysis was improved by a minimum of 6.4 times, and possibly by greater than ten-fold.
2
Ellis, Michael Martin. "Formation of pure polycrystalline alpha-alumina fibers from an organo-metallic sol-gel." Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/20010.
3
Carr, Jason A. "The Utilization of Enzymes in the Synthesis and Modification of Natural and NonNatural Compounds: A Chemo-Enzymatic Approach to Enantiomerically Pure Compounds." Scholar Commons, 2004. https://scholarcommons.usf.edu/etd/983.
Анотація:
The employment of enzymes and whole cells has been important in many industries for centuries. However, it is only in the last 30 years that the use of enzymes for the synthesis of high-value fine chemicals has enjoyed increasing popularity. In fact, esterases and lipases are used almost routinely these days to provide optically active building blocks for the construction of imaginative new routes to chiral target molecules. The major topic of this work describes the utilization of enzymes (namely lipases) in the synthesis and modification of natural and non-natural compounds.
Chapter 1 outlines the strengths and weaknesses of the most widely used enzyme systems and a description of a brief summary on the state of the art of biotransformations with special emphasis on the general applicability and reliability of various reaction types is described.
Chapter 2 describes the enzymatic resolution of various 3-acetoxy-4-aryl-substituted azetidin-2-ones. Following screening of enzymes, such as Novozym-435, PS-30, PPL and AYS the best conditions were a phosphate buffer with PS-30 as the enzyme. The resulting products were the (3S, 4R)-3-hydroxy-4-aryl-substituted azetidin-2-ones and the unreacted (3R, 4S)-3-acetoxy-4-aryl-substituted azetidin-2-ones. Reactions generally occurred with high conversion and high selectivity.
In Chapter 3, the regioselective transesterifications and hydrolysis of peracylated sophorolipid (SL) derivatives catalyzed by lipases was investigated. It was confirmed from the detailed spectral analysis of the products that transesterification failed to furnish any free hydroxyls on the sophorose ring. Instead, transesterification took place on the methyl ester located at the carboxylic end of the 17-hydroxyoctadecenoic acid chain attached to the C-1' position of the sophorose ring.
In Chapter 4, the chemo-enzymatic syntheses of enantiomerically pure R and S imperanene from vanillin are described. The key step entails the asymmetrization of a prochiral diol using lipase PS-30. The resulting monoacetate has enantiomeric excesses of >97%.
Biocatalysts represent a new class of chiral catalysts useful for a broad range of selective organic transformations. It is stating the obvious to say that biocatalysis is not a panacea for synthetic organic chemistry. However, advances over the past thirty years mean that it would be a serious mistake not to consider the employment of a biocatalyst, in, perhaps, the key step in a sequence of transformations that turn a cheap starting material into an expensive fine chemical.
4
Carr, Jason A. "The utilization of enzymes in the synthesis and modification of natural and non-natural compounds a chemo-enzymatic approach to enantiomerically pure compounds /." [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000420.
5
Mullins, Paul Eric. "Application of COSMO-SAC to Solid Solubility in Pure and Mixed Solvent Mixtures for Organic Pharmacological Compounds." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/31086.
Анотація:
In this work, we present two open literature databases, the VT-2005 Sigma Profile Database and the VT-2006 Solute Sigma Profile Database, that contain sigma profiles for 1,645 unique compounds. A sigma profile is a molecular-specific distribution of the surface-charge density, which enables the application of solvation-thermodynamic models to predict vapor-liquid and solid-liquid equilibria, and other properties. The VT-2005 Sigma Profile Database generally focuses on solvents and small molecules, while the VT-2006 Solute Sigma Profile Database primarily consists of larger, pharmaceutical-related solutes. We design both of these databases for use with the conductor-like screening model â segment activity coefficient (COSMO-SAC), a liquid-phase activity-coefficient model. The databases contain the necessary information to perform binary and multicomponent VLE and SLE predictions. We offer detailed tutorials and procedures for use with our programs so the reader may also use their own research on our research group website (www.design.che.vt.edu). We validate the VT-2005 Sigma Profile Database by pure component vapor pressure predictions and validate the VT-2006 Solute Sigma Profile Database by solid solubility predictions in pure solvents compared with literature data from multiple sources. Using both databases, we also explore the application of COSMO-SAC to solubility predictions in mixed solvents. This work also studies the effects of conformational isomerism on VLE and SLE property prediction. Finally, we compare COSMO-SAC solubility predictions to solubility predictions by the Non-Random Two-Liquid, Segment Activity Coefficient (NRTL-SAC) model. We find UNIFAC is a more accurate method for predicting VLE behavior than the COSMO-SAC model for many of the systems studied, and that COSMO-SAC predicts solute mole fraction in pure solvents with an average root-mean-squared error (log10(xsol)) of 0.74, excluding outliers, which is greater than the RMS error value of 0.43 using the NRTL-SAC model.
Master of Science
6
Nalla, V. "Synthesis of optically pure pharamaceuticals employing aziridines / epoxides as chiral synthons and development of novel biologically active compounds based on benzopyran -4- ones." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2018. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/5854.
7
Pradhan, Rajendra Sharad. "Formulation and in vitro release study of poly(DL-lactide) microspheres containing hydrophilic compounds, glycine and its homopeptides." Scholarly Commons, 1992. https://scholarlycommons.pacific.edu/uop_etds/2831.
Анотація:
In view of current interest in several oligopeptide drugs currently being investigated for controlled implantable delivery, glycine, diglycine, triglycine, tetraglycine and pentaglycine were chosen as model compounds for encapsulation in biodegradable microspheres of DL-polylactide (DL-PLA) by a technique based on oil-in-oil emulsion and the solvent evaporation principle. A DL-polylactide concentration of 10.3% w/w and emulsifier (sorbitan sesquioleate) concentration of 0.3% v/v produced good yields of microspheres with excellent entrapment when processed under following conditions: emulsion time, 1 min; solvent evaporation time, 2 min; internal phase-external phase ratio, 1:7; stirring speed, 1100 rpm; emulsion temperature, 5$\sp\circ$C; and maximum processing temperature, 35$\sp\circ$C. Microspheres prepared as above at four different loadings (2.5, 5.0, 7.5, and 10.0% w/w) were analyzed for morphological and in vitro release characteristics. Analysis of the release data and scanning electron photographs suggested that the release of glycine and its homopeptides from DL-PLA microspheres was most likely by diffusion through the matrix. However, for models having low aqueous solubility, e.g., tetra- and pentaglycine, dissolution played a rate-limiting role. Microspheres of glycine prepared with DL-PLA plasticized with 10% triacetin demonstrated the slowest release, with the first 50% entrapped glycine released over four days and next 25% released at a constant rate over 17 days. This was in sharp contrast to unplasticized microspheres from which glycine was completely leached out in 24 h. Interestingly, while the plasticizer decreased the rate of release of glycine, it appeared to promote the degradation of the polymer DL-PLA.
8
Abubakar, Ibrahim Babangida. "In vitro investigation on synergistic anticancer effects between vitamin E isomers, pure compounds and crude alkaloid plant extracts on human cancerous cells." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/35974/.
Анотація:
Anticancer chemotherapeutic treatment using single dose has been limited due to drug resistance and potential metabolic degradation. For instance, high-dose tocotrienols undergo metabolic degradation that limits the availability of therapeutic dose thereby limiting the potency in vivo. Combined treatment of tocotrienols at low dosage has been suggested as alternative to circumventing this limitation. This study was designed to investigate the cytotoxic effects and subsequently the apoptotic mechanisms of individual doses and combined treatments at lower dosages of tocotrienols (delta and gamma), jerantinines (A and B) and extracts (ethanol and alkaloid crude) from leaves and bark of Ficus hispida, Ficus fistulosa and Ficus schwarzii on lung (A549), brain (U87MG) and colon (HT-29) cancer cell lines. Neutral red uptake assay was conducted to evaluate the antiproliferative effect of individual and combined treatments. Staining techniques (histochemical and fluorescence), COMET assay flow cytometric analysis and immunofluorescence were conducted to evaluate cell morphology, DNA damage, cell cycle arrest pattern and antimicrotubule effects. Finally cell and molecular based assays were conducted to investigate the pathways for induction of apoptosis. Cell viability study revealed that alkaloid crude extracts of leaves and bark of F. fistulosa demonstrated the highest potency with IC50 range of 0.96 – 46.81 µg/ml compared to F. schwarzii (8.79 – 107.9 µg/ml) and F. hispida (15.14 – 49.58 µg/ml) on A549, U87MG and HT-29 cells. Both delta- and gamma-tocotrienols induced antiproliferative effects on A549, U87MG and HT-29 cells with IC50 values of 3.12 - 12.40 µg/ml and 3.17 – 16.36 µg/ml, respectively. Potent antiproliferative effects were also evident for jerantinine A (IC50 0.62 – 1.74 µg/ml), jerantinine B (IC50 0.58 – 1.48 µg/ml) and vinblastine (IC50 0.03 – 0.71 µg/ml). However, similar toxic effects on these three compounds were also evident on non-cancerous lung fibroblast (MRC5) cells. The leaf and bark alkaloid crude extracts of F. fistulosa and F. schwarzii were selected for combined treatments. The combined treatment of IC20 doses of F. fistulosa with both delta- and gamma-tocotrienols induced synergistic antiproliferative effects (combination index (CI) < 1) on U87MG and HT-29 with up to 34.7-fold and 4-fold dose reductions for tocotrienols and F. fistulosa extracts, respectively. In contrast, additive (CI = 0.98) or antagonistic effects (CI > 1) were observed for IC20 doses of F. schwarzii extracts combined with delta- and gamma-tocotrienols on HT-29 cells. On the other hand, combined treatments of tocotrienols (delta and gamma) with IC20 doses of jerantinines (A and B) induced synergistic effects (CI < 1) on A549, U87MG and HT-29 cells causing up to 4.48-fold dose reduction of tocotrienols thus reducing toxicity towards MRC5 cells compared to cancer cells. Further morphological and DNA damage assessment focusing on tocotrienols (delta and gamma), jerantinines (A and B) and combined low-dose treatments revealed anticancer features including cell shrinkage, nuclear chromatin condensation and fragmentation, membrane blebbing, apoptotic bodies and induction of predominantly double stranded DNA breaks. Cell cycle analysis demonstrated the induction of G0/G1 and G2/M cell cycle arrests by tocotrienols (delta and gamma) and jerantinines (A and B), respectively on U87MG, A549 and HT-29 cells. Meanwhile, G2/M (A549) and G0/G1 (U87MG and HT-29) cell cycle arrests were evident for combined low-dose treatments of tocotrienols (delta and gamma) with IC20 doses of jerantinines (A and B). Jerantinines A and B and combined low-dose treatments with tocotrienols (delta and gamma) caused disruption of microtubule networks and induction of caspase 8-, 9- and 3-mediated apoptosis with caspase-independent growth inhibition evidenced in the presence of caspase inhibitors on U87MG, A549 and HT-29 cells. In contrast, although treatments of tocotrienols (delta and gamma) alone caused similar apoptotic features as those of combined, disruption of microtubule networks were not characterized on these three cancer cell lines. Further mechanistic study on U87MG cells revealed that the apoptosis triggered by individual doses of tocotrienols (delta and gamma) involved the activation of TRAIL and Bid as well as the release of cytochrome C, thus confirming the recruitment of the death receptor and mitochondria-mediated pathways. On the other hand, individual doses of jerantinines (A and B) and combined low-dose treatments with tocotrienols resulted in the activation of TRAIL, FAS, p53 and Bid, as well as the release of cytochrome C. The activation of both death receptors, p53 and microtubule disruption by combined low-dose treatments demonstrates an improved mechanism of action comparing to individual doses of tocotrienols and jerantinines. In addition, the combined low-dose treatments also caused a reduction of required potent doses thereby minimizing the toxicity of jerantinines (A and B) towards the non-cancerous MRC5 cells. In conclusion, this research has presented valuable combined treatment candidates which are warranted for further investigations as future chemotherapeutic agents against cancers.
9
Eckard, Phyllis R. "The Investigation of Primary and Secondary Modifiers in the Extraction and Separation of Neutral and Ionic Pharmaceutical Compounds with Pure and Modified Carbon Dioxide." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30500.
Анотація:
A successful supercritical fluid extraction method includes removal of the analyte from the matrix into the bulk fluid as well as trapping or concentration of the analyte prior to analysis. In the first phase of this research, the trapping capacities of three solid-phase traps (glass beads, 50/50 (w/w) glass beads/octadecylsilica), 50/50 (w/w) Porapak Q®/glass beads) were determined as a function of trap composition for a mixture of components varying in polarity and volatility. The Porapak Q®/glass beads mixture was found to be the most successful solidphase investigated exhibiting the highest trapping capacity. The use of the Porapak Q®/glass beads as a solid-phase trap was investigated in later extraction studies in this dissertation.
The extraction of highly polar, multifunctional analytes may not be completely successful with modified carbon dioxide, therefore, a secondary modifier (i.e. additive) may be added directly to the extraction fluid in hopes of improving the recoveries. In the second phase of this research, the effect of secondary modifiers in the subcritical fluid extraction of lovastatin from in-house prepared tablet powder mixtures and MEVACOR® tablets was investigated. The effect of in-line methanol-modifier percentage, additive type (acidic, basic, neutral) to the in-line methanol, and additive concentration on the extraction efficiency were examined. The extraction recoveries of lovastatin from MEVACOR® tablets were shown to be highly dependent on methanol concentration and additive type. Isopropylamine was shown to be the most successful additive investigated. An optimized and reproducible extraction method was developed.
The extraction of ionic compounds with carbon dioxide may be difficult due to the high polarity of the compounds. In the third phase of this research, the addition of ion-pairing additives to the matrix in hopes of forming an ion-pair complex of reduced analyte polarity was investigated. Therefore, a screening study consisting of a fractional-factorial design was performed in order to identify the factors which contribute most to the recovery of an anionic species, triphenylphosphinetrisulfonate (TPPTS), from a spiked-sand surface employing supercritical fluid extraction with carbon dioxide. The experimental parameters investigated were: type of ion-pairing additive (i.e. tetralkylammonium hydrogen sulfates) and its concentration, carbon dioxide density, extraction temperature, static extraction time, CO₂ mass used, liquid CO₂ flow rate, and the volume of methanol spiked into the matrix prior to extraction. Of the eight factors investigated, four factors were identified as significantly affecting the recovery of the anionic species. They were: 1) ion-pairing reagent added to the spiked sand surface and its concentration; 2) static extraction time; and 3) volume of methanol present in the extraction vessel. The experimental parameters and settings identified as influential by the statistical approach were later shown in concert to yield 100% recovery of TPPTS from the spiked-sand.
In the fourth phase, the extraction of a cationic species, pseudoephedrine hydrochloride, from spiked-sand and Suphedrine tablets, with pure and methanol-modified CO₂ was examined. Once the extraction was shown to feasible, several strategies were compared in terms of their effectiveness in enhancing the analyte's extractability. The first strategy involved the addition of ion-pairing additives. Several sodium salts of alkylsulfonic acids varying in lipophilicity and concentration were investigated. The addition of 1-heptanesulfonic acid, sodium salt, in methanol, in a 5:1 mole ratio of reagent to analyte was shown to be the most useful in recovering the drug from the spiked-sand. The second strategy considered the influence of acids and bases and other modifier compositions such as a methanol/water mixture with or without 1-heptanesulfonic acid, sodium salt, on the pseudoephedrine recovery. The recoveries obtained from the drug spiked-sand were shown to comparable in the presence of a methanol/water solution, a tetrabutylammonium hydroxide in methanol solution, and a methanol solution with 1-heptanesulfonic acid, sodium salt. Next the extraction of pseudoephedrine hydrochloride from Suphedrine tablets was performed with pure and modified CO₂. Similar to the sand-spike studies, the effect of the addition of the ion-pairing reagent and other in-cell modifiers were examined. Once again, the recoveries obtained when the matrix was in the presence of a methanol/water mixture and a methanol solution containing 1-heptanesulfonic acid, sodium salt were similar. Finally, the identity of the extracted analyte was determined via IR analyses, and it was shown that pseudoephedrine hydrochloride was indeed extractable from the tablets with in-line modified CO₂ in the absence of any in-cell modifier.
In the last phase of this research, a supercritical fluid chromatographic separation with evaporative light scattering detection was developed for the separation of five phospholipids varying in polarity and ionic characteristics. Several parameters were investigated and shown to be influential in the separation. They were: 1) stationary phase composition, 2) addition of an acidic additive and its concentration, 3) mobile phase ramp rate, and 4) column outlet pressure.Ph. D.
10
Vangani, Saroj. "Development of an in vitro dissolution model to predict the in vivo behavior of poorly soluble compounds." Scholarly Commons, 2010. https://scholarlycommons.pacific.edu/uop_etds/2412.
Анотація:
One of the challenges of biopharmaceutics research is correlating in vitro drug release information with the in vivo drug profiles often known as in vitro-in vivo correlations (IVIVC). These have huge cost savings in pharmaceutical industry. This dissertation describes the development of a novel in vitro dissolution model that has been designed to evaluate the in vitro release of poorly water-soluble model compounds so as to predict their in vivo behavior. The flow through apparatus (USP 4) has been coupled with the compendial dissolution apparatus (USP 2). A bi-phasic dissolution medium has been used to achieve sink conditions. The dissolved drug from the aqueous phase is continuously extracted into the organic phase of the biphasic dissolution medium, mimicking the dynamic process of in vivo absorption. The model can successfully discriminate between the bioequivalent and non-bioequivalent formulations and can be used to establish IVIVC. It was concluded that the model will serve as a surrogate for bioequivalence studies and to support biowaivers.
11
Alajtal, Adel Imhemed. "Raman spectroscopic application for the analysis of organic compounds and minerals of astrobiological significance : the detection and discrimination of organic compounds and mineral analogues in pure and mixed samples of astrobiological significance using raman spectroscopy, XRD and scanning electron microscopy." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/4425.
Анотація:
Raman spectroscopy has been used to characterise both organic and geological samples in order to build a database for the future characterization of biomarker molecules that are of astrobiological relevance. Characteristic geological features and hydrated minerals recently found on the surface of Mars by the NASA planetary rovers Spirit and Opportunity suggest that a possible biosphere could have once existed there. Analytical instrumentation protocols for the unequivocal detection of biomarkers in suitable geological matrices are critical for future unmanned explorations, including the forthcoming ESA ExoMars mission scheduled for 2018. Several geological features found on the surface of Mars by planetary rovers suggest that a possible extinct biosphere could exist based on similar sources of energy as occurred on Earth. For this reason, analytical instrumental protocols for the detection of isolated biomarkers preserved in suitable geological matrices unequivocally and non-destructively have to be evaluated for future unmanned missions. Raman spectroscopy is currently part of the Pasteur instrumentation suite of the ExoMars mission for the remote detection of extant or extinct life signatures in the Martian surface and subsurface. Terrestrial analogues of Martian sites have been identified and the biogeological modifications resulting from extremophilic survival activity have been studied. Here we present the Raman spectral characterization of several examples of organic compounds which have been recorded using 785 nm, 633 nm and 514 nm laser excitation -polycyclic aromatic hydrocarbons (PAHs), organic acids, chlorophyll and carotenoids. Experimental mixtures of ß-carotene in usnic acid, PAHs in usnic acid and PAHs in mineral matrices have also been investigated. Organic compounds and PAHs located under crystalline minerals samples were identified using a 5x objective lens and 785 nm III excitation. The pure compounds and compound mixtures were also analysed using X-ray powder diffraction and scanning electron microscopy (SEM). The results of this study indicate that near infrared laser at 785 nm provided the clearest and the most informative spectra due to the reduction of fluorescence emission. Higher energy lasers operating in the visible region have resulted in the emission of significant background fluorescence. Few samples fluoresce even with the use of 785 nm excitation and FT-Raman spectroscopy remains the instrument of choice for the analysis of these samples.
12
Alajtal, Adel I. "Raman spectroscopic application for the analysis of organic compounds and minerals of astrobiological significance. The detection and discrimination of organic compounds and mineral analogues in pure and mixed samples of astrobiological significance using raman spectroscopy, XRD and scanning electron microscopy." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/4425.
Анотація:
Raman spectroscopy has been used to characterise both organic and geological samples in order to build a database for the future characterization of biomarker molecules that are of astrobiological relevance. Characteristic geological features and hydrated minerals recently found on the surface of Mars by the NASA planetary rovers Spirit and Opportunity suggest that a possible biosphere could have once existed there. Analytical instrumentation protocols for the unequivocal detection of biomarkers in suitable geological matrices are critical for future unmanned explorations, including the forthcoming ESA ExoMars mission scheduled for 2018. Several geological features found on the surface of Mars by planetary rovers suggest that a possible extinct biosphere could exist based on similar sources of energy as occurred on Earth. For this reason, analytical instrumental protocols for the detection of isolated biomarkers preserved in suitable geological matrices unequivocally and non-destructively have to be evaluated for future unmanned missions. Raman spectroscopy is currently part of the Pasteur instrumentation suite of the ExoMars mission for the remote detection of extant or extinct life signatures in the Martian surface and subsurface. Terrestrial analogues of Martian sites have been identified and the biogeological modifications resulting from extremophilic survival activity have been studied.
Here we present the Raman spectral characterization of several examples of organic compounds which have been recorded using 785 nm, 633 nm and 514 nm laser excitation -polycyclic aromatic hydrocarbons (PAHs), organic acids, chlorophyll and carotenoids. Experimental mixtures of ß-carotene in usnic acid, PAHs in usnic acid and PAHs in mineral matrices have also been investigated. Organic compounds and PAHs located under crystalline minerals samples were identified using a 5x objective lens and 785 nm
III
excitation. The pure compounds and compound mixtures were also analysed using X-ray powder diffraction and scanning electron microscopy (SEM). The results of this study indicate that near infrared laser at 785 nm provided the clearest and the most informative spectra due to the reduction of fluorescence emission. Higher energy lasers operating in the visible region have resulted in the emission of significant background fluorescence. Few samples fluoresce even with the use of 785 nm excitation and FT-Raman spectroscopy remains the instrument of choice for the analysis of these samples.
13
Buen, Zachary. "Establishment of gas-phase thermochemical values of various small organic compounds and oligopeptides." Scholarly Commons, 2016. https://scholarlycommons.pacific.edu/uop_etds/262.
Анотація:
The thesis describes utilizing mass spectrometry and computational methods to study two groups of molecular systems: small organic molecules and oligopeptides. The gas-phase acidities were measured and the structures of the molecular species were calculated. The small molecules investigated included methylparaben, ibuprofen, and triclosan, all known to have some biological activity. The gas-phase acidity measurements made for these small molecules had the solvent and collisional gas pressures adjusted in order to observe their potential influences. The results obtained provide insight into the ion chemistry of these molecules and how the energetics may change the observed behavior of the ion as well as the resulting thermochemical properties measured. The oligopeptides studied were a family of tri-peptides in which a cysteine probe was placed within an alanine backbone. The cysteine probe was either in the L- or D- configuration in order to detect any fundamental differences among the diastereotopic peptides. Compared to the L-cysteine isomers, the D-cysteine peptides appear to display a change in gas-phase behavior and their respective dissociation profiles. These changes may have an implication of altering the biochemical properties when chirality changes in biological systems.
14
Nguyen, Hai Trung. "Transfert hydrique dans le milieu poreux réactif : Application à l’étude de séchage d’une pâte pure ettringitique au jeune âge." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI124/document.
Анотація:
Les chapes autonivelantes sont souvent composées de ciment alumineux et de sulfate de calcium pour assurer une prise rapide. Le ciment alumineux est généralement à base de monocalcium aluminate (CA). Récemment, un nouveau ciment alumineux riche en mayénite (C12A7) a été conçu pour optimiser l’application des chapes par l’augmentation de la quantité d’ettringite formée. Le développement de l’hydratation au jeune âge (pendant les premières 24 heures) de ce type de produit est pourtant très peu connu. L’objectif principal de cette étude est d’évaluer l’interaction entre l’hydratation au jeune âge et le séchage naturel à travers un modèle de couplage. Ce modèle est appliqué à l’étude d’une pâte pure ettringitique composée de ciment riche en C12A7 et de plâtre alpha. Tout d’abord, un modèle cinétique d’hydratation, initialement développé en système dilué, a été proposé pour étudier l’hydratation d’une pâte pure ettringitique en condition endogène. Il permet de décrire l’évolution en fonction du temps de la porosité, de la teneur en eau, des quantités de phases (réactifs et hydrates). Un modèle de distribution de rayon de pores a été aussi proposé. Ce modèle permet d’obtenir la courbe de pression capillaire au jeune âge nécessaire pour la modélisation des transferts hydriques. Ensuite, une modélisation complète des transferts hydriques a été présentée. Elle a montré que l’hypothèse d’une pression de gaz constante conduit à une surestimation de perte de masse pour des matériaux à faible perméabilité. Pourtant, pour le cas des ciments alumineux, cette hypothèse peut être retenue pour simplifier le couplage avec le modèle cinétique d’hydratation. Enfin, une modélisation des couplages entre l’hydratation et la dessiccation a été développée. L’originalité de ce modèle porte sur l’intégration de la courbe isotherme issue du modèle de distribution poreuse dans la modélisation des transferts hydriques via une fonction Matlab. Le modèle a été capable de reproduire la cinétique de perte de masse d’un échantillon de pâte pure ettringite réactive soumis au séchage précoce. La nécessité de la prise en compte de l’évolution de température a été mise en évidence. De plus, le modèle a prévu un arrêt précoce de l’hydratation à la surface séchante après 10 heures d’hydratation. L’effet de la dessiccation atteint une profondeur de 5 mm sur un échantillon de 3 cm d’épaisseurSelf-leveling flooring compounds (SLC) are often composed of calcium aluminate cements (CAC) and calcium sulfate to ensure rapid setting. The mineral composition of calcium aluminate cements is usually designed around monocalcium aluminate (CA). Recently, a new cement with the main compound of mayenite (C12A7) has been designed to optimize the application of SLC by increasing the amount of ettringite in the hydration product. However, there is a lack of knowledge related to early-age hydration (during the first 24 hours) of this type of product. The main objective of this study is to evaluate the interaction between early-age hydration and natural drying through a coupling model. This model is applied to the study of an ettringite binder composed of cement rich in C12A7 and plaster First, a kinetic model of hydration, initially developed in a diluted system, has been proposed to study the hydration of an ettringite paste under endogenous conditions. It allows to describe the evolution as a function of time of the porosity, the water content, and the quantities of phases (reactants and hydrates). A model of pore size distribution has also been proposed. This model allows us to obtain the capillary pressure curve at early-age, which is necessary for the modeling of moisture transport. Then, a complete modeling of water transfers was presented. It has shown that the assumption of constant gas pressure leads to an overestimation of mass loss for weakly permeable materials. However, for the case of CAC, this hypothesis can be retained to simplify the coupling with the kinetic model of hydration. Finally, a modeling of the coupling between hydration and desiccation has been developed. The originality of this model concerns the integration of the isothermal curve resulting from the pore size distribution model in the modeling of water transfers via a Matlab function. The model was able to reproduce the kinetics of mass loss of a sample of ettringite binder subjected to early drying. The role of temperature was also elucidated. In addition, the model predicted an early stop of hydration on the drying surface after 10 hours of hydration. The effect of desiccation reaches a depth of 5 mm on a sample with a thickness of 3 cm
15
Ramírez-Vélez, Nicolás. "Parametrization of equations of state : definition of a methodology applicable to SAFT models for pure species (with and without association term) and evaluation of their influence on model performances." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0020.
Анотація:
Les modèles thermodynamiques sont au cœur des outils de modélisation en génie des procédés qui fournissent, d’une part, la description, tant qualitative que quantitative des équilibres de phase des mélanges complexes, et d’autres part, une mesure des propriétés énergétiques (enthalpies, entropies, capacités thermiques) nécessaires à l’établissement des bilans énergétique et exergétique. Ce travail s’intéresse en particulier aux équations d’état issues de la théorie statistique des fluides associés (SAFT) appliquées aux corps purs. Notre objectif principal est de proposer des méthodes de paramétrage universelles et systématiques de ces modèles incluant, en particulier, les paramètres d’association qui traduisent, pour l’essentiel, l’influence que les liaisons hydrogène présentes dans un fluide pur exercent sur ses propriétés thermodynamiques. En utilisant une des variantes les plus populaires de la famille SAFT (le modèle PC-SAFT), nous avons cherché quelles sont les propriétés expérimentales les plus pertinentes à considérer pour régresser les paramètres de corps purs (m,σ,ϵ/k) qui suffisent à décrire les composés non associés. Nous avons montré que seules la pression de vapeur saturante et la densité du liquide s’avèrent strictement nécessaires pour obtenir une description fiable de la thermodynamique d’un corps pur non associé (i.e., de ses propriétés d’équilibre de phases et de ses propriétés énergétiques). Ce travail a produit également une base de données de paramètres pour 1800 corps purs, répartis en 1252 espèces non associées et 548 espèces auto-associées (traitées comme des espèces non-associées). En utilisant ce paramétrage, nous avons pu décrire avec précision plus de 70 % de tous les composés, et parmi eux, près de 60 % des composés auto-associés ont été correctement représentés. L'influence du terme d'association sur les performances de l’équation d’état a ensuite été étudiée pour une famille de molécules fortement associées : les alcools linéaires. Ceci nous a permis de tirer trois conclusions majeures : 1) le terme d'association améliore nettement l’efficacité des modèles SAFT dans le cas des molécules associées ; 2) dans l’éventualité où les mêmes paramètres d'association sont utilisés pour l’ensemble des composés de la famille, des données de pression de vapeur saturante et de densité du liquide suffisent pour estimer les paramètres d’association et 3) si l’on opte pour des paramètres d’association spécifiques à chaque constituant, des données de propriétés dérivées doivent être incluses dans la régression (par exemple, la capacité thermique du liquide). Dans une seconde partie, nous exposons une méthodologie pour l’évaluation des performances d’équations d’état des mélanges au développement duquel nous avons participé, ainsi que son application au modèle UMR-PRUThermodynamic models are at the heart of modeling tools in process engineering that provide, on the one hand, the description, both qualitative and quantitative, of phase equilibria of complex mixtures, and on the other hand, a measure of energetic properties (enthalpies, entropies, heat capacities) necessary to establish energy and exergy balances. This work is particularly interested in the equations of state from the statistical associating fluid theory (SAFT) applied to pure compounds. Our main objective is to propose universal and systematic parameterization methods for these models including, in particular, the association parameters which essentially reflect the influence that hydrogen bonds have on the thermodynamic properties of a pure fluid.Using one of the most popular variants of the SAFT family (the PC-SAFT model), we have investigated which experimental properties are most relevant to consider when regressing the pure body parameters (m,σ,ϵ/k) that are sufficient to describe the non-associated compounds. We have shown that only the saturating vapor pressure and the density of the liquid are found to be strictly necessary to obtain a reliable description of the thermodynamics of a non-associated pure body (i.e., its phase equilibrium properties and energy properties). This work has also produced a database of parameters for 1800 pure bodies, divided into 1252 non-associated species and 548 self-associated species (treated as non-associated species). Using this parameterization, we were able to accurately describe over 70% of all compounds, and of these, nearly 60% of the self-associated compounds were correctly represented.The influence of the association term on the performance of the equation of state was then studied for a family of strongly associated molecules: the linear alcohols. This allowed us to draw three major conclusions: 1) the association term significantly improves the efficiency of SAFT models for associated molecules; 2) in the event that the same association parameters are used for all compounds in the family, saturation vapor pressure and liquid density data are sufficient to estimate the association parameters and 3) if component-specific association parameters are chosen, derived property data must be included in the regression (e.g., liquid heat capacity).In a second part, we present a methodology for the evaluation of the performance of equations of state of mixtures in the development of which we participated, and its application to the UMR-PRU model
16
Wiser, Lauren Sample. "Mechanisms of polymer adsorption in nanoparticle stabilization for poorly water soluble compounds." Scholarly Commons, 2011. https://scholarlycommons.pacific.edu/uop_etds/159.
Анотація:
In this dissertation, the mechanisms of nanosuspension stabilization via polymer adsorption on nanoparticle surface were investigated. As the electrokinetic behavior and colloidal stability depend on the surface characteristics, altering the surface adsorbed polymers affords the different surface properties of nanoparticles and leads to the insight on the mechanism of nanoparticle stabilization. Drug nanosuspensions were prepared by wet milling of drug with water as medium and polymers as stabilizers. Block copolymers were evaluated based on varying the hydrophobic and hydrophilic amounts, polymer concentration, and polymer affinity differences onto the nanoparticle surface. Specifically, block copolymers of ethylene oxide (EO) and propylene oxide (PO) with different EO chain lengths were used to modify the nanoparticle surface and investigate the mechanisms of stabilization by varying the ratio of hydrophobic (PO) and hydrophilic (EO) units. It was hypothesized that the PO chain of block copolymers adsorb at the solid-solution interface and the EO chain provides steric hindrance preventing aggregation. Block copolymer adsorption layer thicknesses were experimentally determined with adsorption layer thicknesses increasing from 4.7 to 9.5 nm as the number of EO increase from 26 to 133 monomer units. Nanoparticle aggregation occurred with insufficient polymer monolayer coverage and electrokinetic zeta potential greater than -20 mV. The amount of block copolymers on the surface of nanoparticles was quantified and the affinity of polymer adsorption increased as the copolymer hydrophobic units increased. The amount adsorbed and affinity provides a qualitative ranking of the affinities between a specific polymer and nanoparticle substrate to provide a method in determining the mechanism of stabilization, where specific functional groups for adsorption could be selected for maximum nanoparticle stability. A molecular modeling was conducted to visualize and support the mathematical model and the proposed mechanism of block copolymer adsorption onto a nanoparticle surface. The time lapse molecular modeling of a block copolymer in an aqueous media showed the hydrophobic units adsorbing onto the nanoparticle surface with the hydrophilic units projecting into the aqueous media. For the first time in pharmaceutical research, a systematic series of studies were conducted to elucidate the mechanisms of adsorption with both surface charge and polymer affinity analyses. A series of studies evaluating the adsorption properties polymer stabilizers provided useful information on how a block copolymer comprised of both hydrophilic and hydrophobic domains adsorbs onto an active pharmaceutical ingredient. A systematic set of experimental techniques were presented with novel analysis tools and predictors to construct stable nanoparticle formulations.
17
Anderson, Michael D. 1980. "Novel Misfit Layer Systems: Synthesis and Characterization." Thesis, University of Oregon, 2011. http://hdl.handle.net/1794/12092.
Анотація:
xxiv, 265 p. : ill. (some col.)Stabilizing mechanisms and design considerations for generating misfit layer compounds with a variety of different structural motifs were explored using designed precursors consisting of elemental layers. Layer order in the precursor film and the behavior of binary reaction couples was used to avoid undesirable reaction intermediates. Electron diffraction patterns of CuCr2 Se4 were inconsistent with prior reports that this compound has the spinel structure and were more consistent with a hexagonal R 3 ̄ structure. STEM imaging also suggests CuCr2 Se4 prepared using the compositionally modulated kinetic trapping approach is a new polymorph of the spinel structure. Electrical and magnetic properties were consistent with prior literature reports. Magnetic susceptibility measurements show pronounced hard and easy axes of magnetization not previously documented, which are consistent with a hexagonal crystal symmetry. The [{(PbSe)m }0.99 (WSe2 )n ] r and [{(PbSe)m }1.00 (MoSe2 )n ] r systems were investigated by STEM, XRD and density functional theory (DFT) modeling. No crystallographic registration between MSe and TSe 2 layers was observed and the diffraction observed in the hk 0 and hkl directions, where h = k = 0, can be described by diffraction from discrete layers of finite thickness. A distortion of the MX structure for m > 4 was documented. The distortion in MSe layers was largest for m = 2 and independent of TSe2 thickness. A novel family of compounds, [{(FeSe)m }1+y (NbSe 2 )n ]r , were synthesized inspired by a geological precedent. Single FeSe and NbSe2 layer thicknesses ((0.571 ± 0.005) nm and (0.653 ± 0.002) nm respectively) are consistent with literature values for the binary compounds. STEM-HAADF images of the [{(FeSe) 5 }1+y (NbSe2 )5 ]r revealed a multilayer structure with two distinct structural subunits. STEM-EELS analysis of the film showed no intermixing between the Nb and Fe regions within the limit of the measurement. Another family of misfit layer compounds, [{(NbSe2 )m }1+y (CuCr2Se4)n]r, designed to test requirements for a stable misfit layer compound, were successfully synthesized. STEM analysis of the [{(NbSe2 )5 }1+y (CuCr2 Se4 ) 1 ]r compound showed a well segregated film with two distinct subunit structures. Thicknesses for individual layers of NbSe2 or CuCr2 Se4 ((0.648 ± 0.004) nm and (1.76 ± 0.01) nm respectively) are consistent with prior literature reports of the individual binary compounds. This dissertation includes previously published and unpublished co-authored material.
Committee in charge: Dr. Mark C. Lonergan, Chair; Dr. David C. Johnson, Advisor; Dr. James Hutchison, Member; Dr. Catherine Page, Member; Dr. Stephen Gregory, Outside Member; Dr. Ian M. Anderson, Honorary Member
18
Park, Jongik. "Photoemission Study of the Rare Earth Intermetallic Compounds RNi2Ge2 (R=Eu, Gd)." Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Science ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2004. http://www.osti.gov/servlets/purl/835299-eRe3PQ/webviewable/.
19
Yang, Ning. "Synchrotron Diffraction Studies of Spontaneous Magnetostriction in Rare Earth Transition Metal Compounds." Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Science ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2004. http://www.osti.gov/servlets/purl/835381-gxv1Km/webviewable/.
20
Yanto, Yanto. "Evaluation of novel enoate reductases as potential biocatalyst for enantiomerically pure compound synthesis." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39576.
Анотація:
Asymmetric synthesis with biocatalyst has become an increasingly interesting and cost effective manufacturing process in fine chemicals, pharmaceuticals, and agrochemical intermediates. Enoate reductases from the Old Yellow Enzyme family offer high substrate efficiency, region, stereo-, and enantioselectivity in the catalyzed biotransformations. Asymmetric reduction of activated C=C bond is one of the most widely applied synthetic tools for the potential to generate up to two stereogenic centers in one step reaction. The thesis contributed to the development and characterization of the Old Yellow Enzyme family members including NRSal from Salmonella typhimurium, YersER from Yersinia bercoviei, KYE1 from Kluyveromyces lactis, and XenA from Pseudomonas putida. We explored the possible new chemistry, gathered further understanding of enzymes functionality and biochemistry, evaluated parameters such as enzyme stability, productivity, and selectivity, and improved enzyme specificity through computational guided protein engineering method. In overall, the increasing knowledge about this Old Yellow Enzyme family together with recent advances in biotechnology renders the enoate reductases a tool of choice for industrial applications.
21
Farris, Joshua Ryan. "Pure, compound, or composite humans : a constructive theological philosophical exploration of dualistic human ontology and origins." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.687270.
Анотація:
As a work of constructive philosophical-theology, this disse11ation offers an account of theological anthropology by drawing from person-body substance dualism (e.g. pure, compound, and composite). To that end, I (i) philosophically defend substance dualism and parse out three kinds of substance dualism for exploration; (ii) show how substance dualism ontology persuasively accounts for the Scriptural narrative on human beings (the interface of philosophy and biblical-theology); (iii) defend person-body substance dualism as the most natural accounting for the New Testament teaching on the afterlife; (iv) constructively link contemporary dualism to the debate on the origin of the soul and put forward one novel model of origins; (v) draw out the implications from the various views on the soul's origin.
22
Ayala, A. "Aspects of the SrO-CuO-TiO2 Ternary System Related to the Deposition of SrTiO3 and Copper-Doped SrTiO3 Thin-Film Buffer Layers." Washington, D.C : Oak Ridge, Tenn. : United States. Dept. of Energy ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2004. http://www.osti.gov/servlets/purl/836697-HiUEwz/native/.
Анотація:
Thesis (Ph.D.); Submitted to the Univ. of New Mexico, Albuquerque, NM (US); 20 Dec 2004.Published through the Information Bridge: DOE Scientific and Technical Information. "LA-14197-T" A. Ayala. 12/20/2004. Report is also available in paper and microfiche from NTIS.
23
Giocondo, Maísa Pasquotto. "Avaliação da atividade apoptótica de substância pura isolada de Cryptocarya mandioccanna em células de carcinoma cervical imortalizadas pelo papilomavirus humano (HPV) /." Araraquara : [s.n.], 2007. http://hdl.handle.net/11449/89140.
Анотація:
Orientador: Christiane Pienna SoaresBanca: Cleslei Fernando Zanelli
Banca: Andreimar Martins Soares
Resumo: Diversos estudos buscam identificar compostos com atividade seletiva para celulas tumorais e que possuam mecanismo de acao para desencadear a apoptose. Dentre as substancias isoladas de Cryptocarya sp, algumas estirilpironas, como a goniotalamina, apresentam atividade antiproliferativa e apoptogenica em diferentes linhagens celulares. No presente estudo, foram avaliadas as atividades citotoxica e pro-apoptotica da estirilpirona (criptomoscatona D2) isolada de Cryptocarya mandioccana, em linhagens celulares de carcinoma cervical humano infectada por HPV (HeLa e SiHa), nao infectada (C33A) e fibroblasto pulmonar humano transformado pelo SV-40 (MRC-5). A atividade citotoxica foi avaliada pelo ensaio do MTT e a apoptose foi avaliada, respectivamente, pelos ensaios de anexina V e a expressao de bak/bcl-2, por citometria de fluxo. Para o ensaio do MTT, as celulas foram tratadas com estirilpirona (criptomoscatona D2) nas concentracoes de 15, 30, 60 e 90-ÊM por 6, 24 e 48 horas e por 6 horas com periodo de recuperacao de 24, 48 e 72 horas pos tratamento. Para os ensaios de apoptose, as celulas foram tratadas por 6 horas e periodo de recuperacao de 24, 48 e 72 horas. O tratamento com a estirilpirona (criptomoscatona D2) ocasionou elevada citotoxicidade dose-resposta e tempo-resposta em HeLa, SiHa, C33A e MRC-5. Embora nao haja diferenca estatisticamente significativa de citotoxicidade entre as linhagens, aparentemente a citotoxicidade foi maior em HeLa e C33A (tratamento de 24 e 48 horas) que em MRC-5 e SiHa. Ainda, no periodo de recuperacao, HeLa e SiHa aparentemente restabelecem sua capacidade proliferativa, que e diretamente proporcional ao tempo de recuperacao, enquanto o mesmo comportamento nao e observado em C33A. Ao avaliar a expressao de duas proteinas da via intrinseca de apoptose (bcl-2 e bak), nao foi observada modulacao dessa expressao entre as linhagens celulares, nas diferentes tempos de recuperação pos-tratamento.
Abstract: Several attempts have been made to identify chemical compounds with selective cytotoxicity against cancer cells and apoptosis trigger activity. Among the substances isolated from Cryptocarya sp, some styrylpyrones, such as goniothalamine, demonstrate antiproliferative and apoptotic activity in abroad human cell lines. In the present study, we evaluated the antiproliferative and apoptotic activities of the styrylpyrone (cryptomoschatone D2) isolated from Cryptocarya mandioccana in HPV-infected (HeLa and SiHa) and non-infected (C33A) human cervical carcinoma cell lines, and in human lung's fibroblast immortalized with SV-40 (MRC-5). The antiproliferative activity was evaluated by the MTT assay and the apoptotic activity was investigated by measuring the expression levels of annexin V and bak/bcl-2 by flow cytometry. In the MTT assay, cells were treated with styrylpyrone (cryptomoschatone D2) at a 15, 30, 60 or 90ìM concentration for 6, 24 or 48 hours as well as for 6 hours followed by a recovery posttreatment period of 24, 48 or 72 hours. In the apoptotic assays, cells were treated for 6 hours followed by a recovery posttreatment period of 24, 48 or 72 hours. High cytotoxicity (dose-response and time-response) was observed in HeLa, SiHa, C33A and MRC-5 cell lines. Although the styrylpyrone cytotoxicity was not significantly different among the cell lines tested, the citotoxicity was apparently higher in HeLa and C33A than MRC-5 and SiHa in the case of treatments for 24 or 48 hours. Moreover, HeLa and SiHa were able to recover their prolifetative status, which were directly proportional to the posttreatment recovery time. On the other hand, C33A did not demonstrate a similar posttreatment recovery. Despite the posttreatment recovery time, the expression of the apoptotic proteins bcl-2 and bak seems not to be modulated by the treatment.
Mestre
24
Gosso, Jean-Pierre. "Spectroscopie Raman des excitations magnétiques dans les fluorures antiferromagnétiques cobalteux purs ou desordonnés par substitution." Paris 13, 1986. http://www.theses.fr/1986PA132007.
Анотація:
Description des excitations magnétiques dans k::(2) cof::(4) et rb::(2) cof::(4) par un modèle multi-excitonique construit sur un hamiltonien comprenant champ cristallin, couplage spin-orbite et échange de heisenberg opérant sur le multiplet fondamental de l'ion cobalt en champ cristallin cubique. L'interprétation pour les composés désordonnés par substitution d'un ion magnétique mn se fait par fonctions de green ou modèle de champ moléculaire
25
Giocondo, Maísa Pasquotto [UNESP]. "Avaliação da atividade apoptótica de substância pura isolada de Cryptocarya mandioccanna em células de carcinoma cervical imortalizadas pelo papilomavirus humano (HPV)." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/89140.
Анотація:
Made available in DSpace on 2014-06-11T19:23:44Z (GMT). No. of bitstreams: 0
Previous issue date: 2007-06-01Bitstream added on 2014-06-13T18:51:18Z : No. of bitstreams: 1
giocondo_mp_me_arafcf.pdf: 1362305 bytes, checksum: 5d252e88df73be4c96290a8a2c37f546 (MD5)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Universidade Estadual Paulista (UNESP)
Diversos estudos buscam identificar compostos com atividade seletiva para celulas tumorais e que possuam mecanismo de acao para desencadear a apoptose. Dentre as substancias isoladas de Cryptocarya sp, algumas estirilpironas, como a goniotalamina, apresentam atividade antiproliferativa e apoptogenica em diferentes linhagens celulares. No presente estudo, foram avaliadas as atividades citotoxica e pro-apoptotica da estirilpirona (criptomoscatona D2) isolada de Cryptocarya mandioccana, em linhagens celulares de carcinoma cervical humano infectada por HPV (HeLa e SiHa), nao infectada (C33A) e fibroblasto pulmonar humano transformado pelo SV-40 (MRC-5). A atividade citotoxica foi avaliada pelo ensaio do MTT e a apoptose foi avaliada, respectivamente, pelos ensaios de anexina V e a expressao de bak/bcl-2, por citometria de fluxo. Para o ensaio do MTT, as celulas foram tratadas com estirilpirona (criptomoscatona D2) nas concentracoes de 15, 30, 60 e 90-ÊM por 6, 24 e 48 horas e por 6 horas com periodo de recuperacao de 24, 48 e 72 horas pos tratamento. Para os ensaios de apoptose, as celulas foram tratadas por 6 horas e periodo de recuperacao de 24, 48 e 72 horas. O tratamento com a estirilpirona (criptomoscatona D2) ocasionou elevada citotoxicidade dose-resposta e tempo-resposta em HeLa, SiHa, C33A e MRC-5. Embora nao haja diferenca estatisticamente significativa de citotoxicidade entre as linhagens, aparentemente a citotoxicidade foi maior em HeLa e C33A (tratamento de 24 e 48 horas) que em MRC-5 e SiHa. Ainda, no periodo de recuperacao, HeLa e SiHa aparentemente restabelecem sua capacidade proliferativa, que e diretamente proporcional ao tempo de recuperacao, enquanto o mesmo comportamento nao e observado em C33A. Ao avaliar a expressao de duas proteinas da via intrinseca de apoptose (bcl-2 e bak), nao foi observada modulacao dessa expressao entre as linhagens celulares, nas diferentes tempos de recuperação pos-tratamento.
Several attempts have been made to identify chemical compounds with selective cytotoxicity against cancer cells and apoptosis trigger activity. Among the substances isolated from Cryptocarya sp, some styrylpyrones, such as goniothalamine, demonstrate antiproliferative and apoptotic activity in abroad human cell lines. In the present study, we evaluated the antiproliferative and apoptotic activities of the styrylpyrone (cryptomoschatone D2) isolated from Cryptocarya mandioccana in HPV-infected (HeLa and SiHa) and non-infected (C33A) human cervical carcinoma cell lines, and in human lung's fibroblast immortalized with SV-40 (MRC-5). The antiproliferative activity was evaluated by the MTT assay and the apoptotic activity was investigated by measuring the expression levels of annexin V and bak/bcl-2 by flow cytometry. In the MTT assay, cells were treated with styrylpyrone (cryptomoschatone D2) at a 15, 30, 60 or 90ìM concentration for 6, 24 or 48 hours as well as for 6 hours followed by a recovery posttreatment period of 24, 48 or 72 hours. In the apoptotic assays, cells were treated for 6 hours followed by a recovery posttreatment period of 24, 48 or 72 hours. High cytotoxicity (dose-response and time-response) was observed in HeLa, SiHa, C33A and MRC-5 cell lines. Although the styrylpyrone cytotoxicity was not significantly different among the cell lines tested, the citotoxicity was apparently higher in HeLa and C33A than MRC-5 and SiHa in the case of treatments for 24 or 48 hours. Moreover, HeLa and SiHa were able to recover their prolifetative status, which were directly proportional to the posttreatment recovery time. On the other hand, C33A did not demonstrate a similar posttreatment recovery. Despite the posttreatment recovery time, the expression of the apoptotic proteins bcl-2 and bak seems not to be modulated by the treatment.
26
Folden, III Charles Marvin. "Development of odd-Z-projectile reactions for transactinide element synthesis." Berkeley, Calif. : Oak Ridge, Tenn. : Lawrence Berkeley National Laboratory ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2004. http://www.osti.gov/servlets/purl/843003-RuBpYI/native/.
Анотація:
Doctoral Dissertation, Ph.D., University of California, Berkeley, Berkeley, California, USA.Published through the Information Bridge: DOE Scientific and Technical Information. "LBNL--56749" Folden III, Charles Marvin. USDOE Director. Office of Science. Office of Nuclear Physics 11/04/2004. Report is also available in paper and microfiche from NTIS.
27
Raimund, Stefan. "Sources and fluxes of volatile halogenated organic compounds in highly productive marine areas." Brest, 2010. http://www.theses.fr/2010BRES2022.
Анотація:
Les Composés Halogénés Organiques Volatils (VHOC) sont des composès qui influencent largement la chimie atmosphérique et qui ont des sources naturelles et anthropiques. La production biogénique, les sources marines et les flux à l’interface air-mer de ces composés sont encore peu connues et ont fait l’objet de cette étude. Un système analytique et de nouveaux systèmes de prélèvement ont été développés. Lors d’un travail au laboratoire, il a été démontré que la communication plante-plante orchestre la formation des VHOC : une algue pré-traitée réagit moins intensément après réception d’un signal oligoguluronate. Ceci pourrait être bénéfique pour l’algue en termes d’efficacité de coûts. Les distributions et les flux air-mer de VHOC ont été étudiés dans deux systèmes marins très productifs : une région d’upwelling dominée par les dïatomées et une région côtière en régime mégatidal enrichie en nutriments et riche en macroalgues. Les principaux résultats ont montré que (1) les zones d’upwelling ne sont pas caractérisées par de fortes teneurs en VHOC, (2) dans les zones influencées par la marée, la marée a des effets significatifs sur la formation des composés iodés et bromés mais n’influence pas la formation des composés chlorés (à l’exception du chloroforme qui montre une légère dépendance dans l’upwelhng ibérique) (3) les composés bromés ont des sources côtières importantes et localisées (4) les composés iodés ont des sources qui ne sont pas strictement liées aux macroalgues (5) que les principales sources de composés chlorés auraient une origine anthropique et (6) la formation des halocarbonés et leurs flux vers l’atmosphère montrent des variations saisonnières marquéesVolatile halogenated organic compounds (VHOCs) constitute a large group of environmental gases that can influence atmospheric chemistry, and have natural and anthropogenlc sources, Marine sources and fluxes, and biogenic production are poorly investigated. During this thesis we designed an analytical system and sampling devices for measurements of halocarbons which showed high performance, both at sea and during laboratory analyses. In a laboratory experiment it could be demonstrated that plant-plant communication orchestrates the formation of VHOCs: “forewarned” algae react less intensely after perception of an oligoguluronates signal. This might be beneficial for the algae in terms of cost efficiency. Two highly productive marine areas were studied for VHOC distribution and air-sea fluxes: a diatom dominated upwelling region and a nutrient enriched coastal region with an important macroalgae cover and a mega-tidal regime. The main findings are (1) upwelling regions are not characterized by high internal VHOC formallon, (2) in tidal-lnfiuenced marine areas tides have significant effects on the formation of iodo- and bromocarbons but no influence on the formation of chlorocarbons (with the exception of chloroform, which showed minor dependence on tides in the Iberian upwelling), (3) bromocarbons have strong and highly localized coastal sources (4) iodocarbons have sources that are not strictly related to macroalgae, (5) main sources of chlorocarbons might have an anthropogenic origin and (6) formation of halocarbons and their fluxes to the atmosphere show a marked seasonality
28
Chemla, Philippe. "Reactions diastereospecifiques de dienones fer-tricarbonyle : applications a la synthese d'alcools fonctionnalises optiquement purs." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13049.
Анотація:
La methode de synthese utilisee permet d'acceder avec de bons rendements, a des composes de haute purete optique et de configuration donnee: alpha et gamma aldols et une delta -lactone fonctionnalisee en position 5. Des hydrocarbures optiquement actifs dont le centre asymetrique est eloigne de toute fonction, ont egalement ete synthetises par cette voie
29
Maroly, Anupam. "The development of a sensitive method to study volatile organic compounds in gaseous emissions of lung cancer cell lines." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2423.
Анотація:
The ultimate objective of this research was to develop a low cost, reliable system that
would lead to early detection of lung cancer. Tests involved the quantitation of gaseous
metabolic emissions from immortalized lung cancer cell lines in order to correlate the
chemical markers to be of cancerous origin. The specific aims of the project were the
study of gas emissions in selected cancer cell lines and identification of volatile organic
compounds (VOCs) in them.
Disadvantages of earlier studies were that the measurements were not real time or state
specific so that molecular identification was often inconclusive. Furthermore the methods
of study used in the past were not quantitative, which limited their practicality for
medical applications. We felt the need to prove or disprove these earlier results using a
new technique.
The method we proposed is different and unique when compared to previous methods
because cell lines have not been studied extensively for cancer markers. We have studied
cancer cell lines which are adherent, immortalized cultures originating from primary
tumors obtained from patients with no prior treatment for lung cancer.
We have used an alternative method for the spectrometric analysis and quantitation of the
selected chemical markers. The pre-concentration method involved a Purge and Trap
unit with a thermal desorber where the vapor concentration was enhanced. The
concentrated head space gases were analyzed using a Gas Chromatograph ?? Mass
Spectrometer setup. This setup eliminated the bulky apparatus used in earlier studies. It is
simpler in design and more comprehensive so that external factors such as patient??s diet,
habitat and lifestyle do not contribute to our study of recognition of cancer markers.
Based on the results obtained in the above experiments, a more comprehensive,
inexpensive study of lung cancer related markers could be made.
The first section, after giving an introduction to lung cancer, goes on to explain the
background work done by other researchers on cancer. The third section gives a detailed
explanation of the experimental setup. This is followed by all the tests conducted with
corresponding results. The final section deals with the conclusions drawn from all
experiments.
30
Silva, Laiane Torres. "Revestimentos comestíveis à base de purê de manga e alginato de sódio para retenção de compostos voláteis em mangas minimamente processadas." Universidade Federal Rural do Semi-Árido, 2011. http://bdtd.ufersa.edu.br:80/tede/handle/tede/57.
Анотація:
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Previous issue date: 2011-02-25Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The responses to mechanical damage caused by minimal processing can accelerate the loss of quality and modify the sensory attributes. Besides cooling, which is considered the main technique available to retard the undesirable effects of minimal processing, the use of barriers to O2/CO2 and water vapor can contribute in controlling senescence, maintaining the quality and extending the shelf-life. The objective of this study was to develop an edible coating based on mango puree and sodium alginate with minimal permeability to water vapor and the potential to form a thin gel layer around 'Tommy Atkins' minimally processed mango slices (MPM), capable of controlling gas exchange and water loss by the product, in order to maintain its quality and retain volatile compounds for a longer time. Eleven films were prepared, according to a central composite design with two variables, namely alginate concentration in the coatings and immersion time in calcium chloride. In a second part of the experiment, 'Tommy Atkins' mangoes, bought in the market, were washed, sanitized, peeled and cut into slices. MPM were immersed in the film forming solution for 30 seconds, and then in calcium chloride (1%) for 15 seconds, subsequently being disposed for 60 minutes on stainless steel sieve to drain. After this processing, 200g MMP were packed in polyethylene terephthalate trays with lids and stored under refrigeration (10 ± 2ºC) for six days. Every three days samples were collected to quantify the mass loss, pH, titratable acidity (TA), soluble solids (SS), SS/TA ratio, vitamin C, total sugars, polyphenoloxidase activity and volatile compounds. The experiment was conducted using CRD in 3 x 3 factorial design, with three treatments (control plus two coatings) in three storage times (1, 3, and 6 days). Data was subjected to analysis of variance; means of analysis of volatile compounds were compared by the method of Scott-Knott at 5% probability, and the average remaining analyses were compared by Tukey test at 5%. The edible films resulted in different water vapor permeabilities (WVP) as a function of the variables analyzed. The lowest WVP under the conditions used was 0.31 kPa mm-1 m-2, for 1% alginate and 15 seconds of immersion in CaCl2, and was therefore adopted as reference for the preparation of edible coatings. Analyses in gas chromatography-mass spectrometry revealed -3-carene as major constituent in mango aroma, and the same was used in this study as an indicator to assess the retention of volatile compounds of edible coatings. The mangoes coated with mango puree + sodium alginate (1%) exhibited the highest levels of this compound (64.47%). The edible coating (mango puree + sodium alginate) was efficient in maintaining the quality and retaining the -3-carene in mangos 'Tommy Atkins , stored at 10ºC for six days
As respostas aos danos mecânicos provocados pelo processamento mínimo podem acelerar a perda de qualidade e modificar os atributos sensoriais. Além da refrigeração, que é considerada a principal técnica disponível para retardar os efeitos indesejáveis do processamento mínimo, o uso de barreiras ao O2/CO2 e vapor d água pode contribuir no controle dos processos de senescência, na manutenção da qualidade e no prolongamento da vida útil o suficiente para a distribuição, comercialização e consumo. O objetivo desse trabalho foi elaborar um revestimento comestível à base de purê de manga e alginato de sódio com mínima permeabilidade ao vapor d água e com potencial para formar uma fina camada de gel capaz de controlar as trocas gasosas e a perda de água pelo produto, visando manter a qualidade e principalmente reter os compostos voláteis em manga Tommy Atkins minimamente processada (MMP) por maior período de tempo. Foram elaborados onze filmes, de acordo com um delineamento composto central, com duas variáveis, a saber, concentração de alginato nos filmes e tempo de imersão em cloreto de cálcio. Mangas Tommy Atkins , compradas no mercado, foram lavadas, sanitizadas, descascadas e cortadas em fatias. A MMP foi imersa na solução filmogênica, por 30 segundos, e em seguida, em cloreto de cálcio (1%), por 15 segundos, sendo posteriormente disposta, por 60 minutos, em peneira de inox para drenagem. Após esse processamento, 200g de MMP foram acondicionadas em bandejas PET com tampa e armazenadas sob refrigeração (10±2ºC), por seis dias. A cada três dias foram retiradas amostras para a quantificação da perda de massa, pH, acidez titulável, sólidos solúveis, relação SS/AT, vitamina C, açúcares totais, atividade da polifenoloxidase e compostos voláteis. O experimento foi instalado usando DIC em esquema fatorial 3 x 3, com três tratamentos (controle mais dois filmes) em três tempos de armazenamento (1, 3, e 6 dias). Os dados foram submetidos à análise de variância e as médias da análise dos compostos voláteis foram comparadas entre si pelo método de Scott-Knott à 5% de probabilidade, e as médias das demais análises foram comparadas entre si pelo teste de Tukey à 5%. Os filmes confeccionados apresentaram diferentes taxas de permeabilidade ao vapor d água (PVA) em função das variáveis analisadas. A menor PVA dentro das condições utilizadas foi de 0,31 mm kPa-1 m-2, com 1% de alginato e 15 segundos de imersão em CaCl2, portanto, foi adotada como referência para a elaboração de revestimentos comestíveis. Análises em cromatografia gasosa acoplada a espectrometria de massas revelaram -3-careno como constituinte majoritário no aroma da manga, e o mesmo foi utilizado nesse trabalho como indicativo para avaliar a retenção dos compostos voláteis dos revestimentos comestíveis. As mangas revestidas com purê de manga + alginato de sódio (1%) exibiram os maiores teores desse composto (64,47 %). O revestimento comestível (purê de manga + alginato de sódio) se mostrou eficiente em manter a qualidade e em reter o -3-careno, em mangas Tommy Atkins minimamente processadas, armazenadas à 10ºC, por seis dias
31
Renouf, Philippe. "Synthèse asymétrique par hydrolyse enzymatique de diacétates de diénols prochiraux. Nouvelle voie d'accès à des composés optiquement purs." Rouen, 1995. http://www.theses.fr/1995ROUES048.
Анотація:
Une nouvelle synthèse énantiosélective de composés chiraux originaux, possédant un centre stéréogénique quaternaire, a été mise au point, par hydrolyse enzymatique de diacétates de diénols prochiraux. En traitant les 2,4-diacétoxy-cyclohexa-1,4-diènes 3,3-disubstitués par le candida cylindracea lipase, nous obtenons les cétoacétates d'énols correspondants optiquement purs (ee>98%) avec des rendements chimiques élevés. Les excès énantiomériques ont été déterminés par RMN1H en présence de chélates de terre rare à ligands chiraux et/ou par CPG sur phase chirale. La configuration absolue de deux de ces cétoacétates d'énols a été attribuée et au cours de cette détermination, nous avons synthétise un cétol bicyclique (alcool de réduction de la cétone de Wieland-Miescher) optiquement pur. Nous avons ensuite démontré l'intérêt de ces dérivés chiraux comme outils de synthèse. Ils ont permis de synthétiser diverses molécules chirales avec les configurations relative et absolue que l'on désire. Nous avons ainsi, à titre d'exemple, préparé et obtenu optiquement purs les différents énantiomères de la 3-hydroxy-2-méthyl-2-(prop-2-ènyl)-cyclohexanone. Enfin, nous avons élargi la méthode que nous avons mise au point en préparant, par ouverture de cycle, un synthon polyfonctionnel original optiquement pur à haute potentialité synthétique
32
PETIT, YVES. "Synthese d'hydroxy-2 esters enantiomeriquement purs a partir d'amino-2 acide : etude stereochimique de l'addition 1,4 d'organometalliques sur des systemes insatures-2,3 hydroxy-4." Paris 6, 1987. http://www.theses.fr/1987PA066578.
33
Faux-Mallet, Marie-Sabine. "Extraction du gallium(iii) en milieu acide : comparaison des methodes d'extraction liquide-liquide et d'echange d'ions sur resines." Paris 6, 1988. http://www.theses.fr/1988PA066234.
Анотація:
Comparaison des avantages et des inconvenients de l'extraction a l'aide de resines et de l'extraction liquide-liquide en vue de preciser leur domaine respectif d'utilisation en hydrometallurgie. Etude de la separation du gallium contenu dans les solutions d'attaque des minerais de zinc. Utilisation de la resine duolite es467 et pour l'extraction liquide-liquide de l'hydroxy-8 quinoleine et d'une alpha-hydroxy-oxime
34
Vermassen, Aurore. "Adaptation de Staphylococcus xylosus à la matrice carnée, impact des composés nitrosés et utilisation des sources de fer." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22535/document.
Анотація:
Staphylococcus xylosus est couramment utilisé comme ferment dans les produits carnés pour son rôle dans le développement de la flaveur et de la couleur. Beaucoup de propriétés technologiques ont été caractérisées in vitro. Cependant, les mécanismes moléculaires mis en place par cette bactérie pour s’adapter à une matrice carnée et aux composés nitrosés, fréquemment ajoutés dans ces produits, étaient méconnus. Pour identifier ces mécanismes, des approches de transcriptomique globale ont été mises en œuvre. S. xylosus survit dans un modèle viande en modulant l’expression de 55 % de ses gènes. Il surexprime des gènes codant des protéines impliqués dans le catabolisme du glucose et du gluconate et des gènes codant des peptidases. En parallèle, il sous exprime de nombreux gènes impliqués dans la synthèse des acides aminés probablement en raison de leur disponibilité dans le modèle viande. Le modèle viande est un milieu riche en divers substrats et la bactérie pourrait adapter sa physiologie via les régulateurs transcriptionnels CcpA et CodY. S. xylosus répond au sel ajouté au modèle viande en surexprimant des gènes impliqués dans des mécanismes d’osmoprotection, d’extrusion de Na + et de protons. S. xylosus répond aux composés nitrosés dans le modèle viande en modulant 24 % de son génome. Ces composés nitrosés génèrent un stress nitrosant et S. xylosus répond à ce stress par la surexpression de gènes impliqués dans l’homéostasie du fer via la dérépression du régulateur Fur. S. xylosus surexprime aussi des gènes codant des enzymes antioxydants via la dérépression du régulateur PerR. De plus, il surexprime des gènes impliqués dans la réparation de l’ADN et des protéines. La viande est un aliment riche en fer hémique et non hémique. Ainsi, S. xylosus est capable d’acquérir du fer à partir de ferritine, de transferrine et potentiellement des hémoprotéines. La ferritine est une source préférentielle de fer pour S. xylosus. Un opéron codant potentiellement un complexe membranaire impliqué dans des réactions d’oxydo-réduction a été identifié. Un mutant de délétion/insertion dans le premier gène de l’opéron confirme que ce système pourrait jouer un rôle dans l’acquisition du fer de la ferritine chez S. xylosus. Cette étude révèle un changement global dans l’expression des gènes de S. xylosus dans un modèle viande, elle souligne la capacité de S. xylosus à s’adapter à un stress osmotique ou nitrosant et elle caractérise pour la première fois la capacité d’un staphylocoque à utiliser du fer de la ferritineStaphylococcus xylosus is used as starter culture in meat product for its role in the development of flavor and color. S. xylosus is characterized for its technological properties in vitro. However, the molecular mechanisms for its adaptation in meat with or without nitrate and nitrite, frequently added in meat product, remained unknown. Global transcriptomic approaches were carried out to determine the molecular mechanisms. S. xylosus modulated the expression of 55 % of the genes to survive in a meat model. Many genes encoding proteins involved in glucose and gluconate catabolisms and peptidases were up expressed. In parallel, a lot of genes involved in amino acids synthesis were down regulated, probably due to their availability in the meat model. The meat model is a rich medium composed of various substrates and S. xylosus adapted its physiology through the transcriptional regulators CcpA and CodY. Finally, it responded to salt added in the meat model in overexpressing genes involved in mechanisms of osmoprotection, Na + and H + extrusion. S. xylosus modulated the expression of 24 % of the genes in presence of nitroso compounds in the meat model. These compounds generated a nitrosative stress. S. xylosus responded to this stress by over expressing genes involved in iron homeostasis through the derepression of the regulator Fur. It over expressed also genes encoding antioxidant enzymes through the derepression of the regulator PerR. Moreover, it over expressed genes involved in DNA and proteins repairs. Meat is rich in hemic and non-hemic iron. S. xylosus is able to grow in presence of ferritin, transferrin and potentially hemoproteins. Ferritin is one of preferential iron sources. An operon encoding potentially a membranous complex involved in oxydo-reduction reactions has been identified. A strain defective in the first gene of the operon confirmed that this complex could contribute to the iron acquisition from ferritin. This study revealed a global change in the gene expression of S. xylosus in the meat model; it highlighted ability of S. xylosus to mitigate nitrosative or osmotic stress, it characterised for the first time the capacity of a Staphylococcus to acquire ferritin-iron
35
Mailhos-Lefievre, Valèrie. "Etude de la pyrolyse des polyamides 11 et 12, purs et ignifugés par le système (decabromodiphenyle-trioxide d'antimoine) : mise en évidence d'une triple synergie brome-antimoine-azote." Paris 13, 1989. http://www.theses.fr/1989PA132003.
36
Prouzet, Eric. "Ordre local dans de nouvelles formes de NiPS obtenues par chimie douce et par intercalation de lithium." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37617740f.
37
Cherradi, Nabih Mohamed. "Propriétés de transport électronique à basse température d'alliages amorphes Au-Si et de multicouches Au/Si." Nancy 1, 1989. http://www.theses.fr/1989NAN10011.
Анотація:
Étude de l'effet des interférences quantiques qui dominent à basse température les propriétés de transport électronique des systèmes désordonnés. Des alliages amorphes au::(X)SI::(1-X) et des multicouches Au-Si ont été préparées par évaporation sous vide d'or et de silicium
38
Shi, Sheng-Hong, and 施昇宏. "The cytotoxicity of pure compounds from Danshen on U937 and HepG2 cancer cell lines." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/62619268773905619879.
Анотація:
碩士高苑科技大學
化工與生化工程研究所
101
Danshen is the most commonly used traditional Chinese traditional Chinese medicine. In modern medicine, Danshen can improve heart function, inhibit liver cell degeneration, expand coronary artery, increase coronary blood flow, and prevent myocardial ischemia. In recent years, tanshinone are also used in the treatment of cervical cancer, stomach cancer, hepatoma, lung cancer, leukemia and other diseases. Tanshinones may inhibit tumor cell proliferation, apoptosis and promote differentiation in some studies. In the study, we use U937 leukemia cells and HepG2 hepatoma cells two cell lines for cells models. Danshen contains purified: Tanshinone I, Tanshinone IIA, Dihydrotanshinone, Dihydrotanshinone I and water-soluble purified: Tanshinol B Salvianolic acid, Salvianolic acid B. For the methods, we use XTT assay to assess cytotoxicity. We use 3 different concentration: 1μM, 5μM, 10μM. The duration are 24hr, 48hr. Conclusion: For U937 cells, Tanshinone I, Tanshinone IIA, Dihydrotanshinone, Dihydrotanshinone I and Tanshinol B have the dose-dependent inhibition on cell’s growth. For HepG2 cells, Tanshinone IIA, Dihydrotanshinone, Dihydrotanshinone I and Tanshinol B have the dose-dependent inhibition on cell’s growth. However, there is no the growth’s inhibiting effect on the two cancer cell lines for Salvianolic acid A and Salvianolic acid B. Interesting, Dihydrotanshinone and Dihydrotanshinone I both have strong cytotoxic effect on both U937 and HepG2 cancer cell lines. The structure of the furan ring C in both pure compounds may play an important role in cytotoxicity. The molecular mechanism of the inhibition of cell growth in these compounds can be studied in the further research.
39
Tung, Pei-Ling, and 董佩綾. "Induction of differentiation by pure compounds of Antrodia cinnamomea in human acute myeloid leukemia cells." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/98890116917118272582.
Анотація:
碩士國立中興大學
生命科學院碩士在職專班
100
Antrodia cinnamomea is a well known medicinal mushroom, and it has been shown to exhibit antioxidant and anticancer treatment effects. Cell differentiation is essential for normal growth and hematopoiesis. Inducing myelopoiesis can potentially serve as differentiation therapy for acute myeloid leukemia (AML). In this study, the ability of pure compounds purified from Antrodia cinnamomea to induce differentiation was studied in culture human myelocytic leukemia HL-60 and KG-1 cells. Treatment of HL-60 and KG-1 cells with Antcin B and Zhankuic acid C significanitly induced cell viability. In contrast, Antcin A, C, and Methyl antcinate A did not shown. The morphological investigation, and used the flow cytometry that also increased the levels of monocyte differentiation markers, CD14 and CD11b in both two cells. The data suggest that Antcin A, B, C, Zhankuic acid C and Methyl antcinate A exerts growth inhibition and monocyte-like differentiation on HL-60 and KG-1 cells through induction differentiation and that chemical compounds purified from Antrodia cinnamomea may have anticancer properties valuable for application in drug products.
40
Huang, Ming-Hsien, and 黃銘賢. "A study on Cometabolic Degradation of Hydrocarbon Compounds by Pure and Mixed Cultures of Methanotrophic Bacteria." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/35760800623261829253.
41
Chang, Mei Yin, and 張美音. "STUDY OF THE EXTRACTS OF PLANTAGO GENUS AND RELATED PURE COMPOUNDS FOR ANTICANCER、ANTIVIRAL AND IMMUNOMODULATORY ACTIVITIES." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/15054467145095441389.
Анотація:
碩士高雄醫學大學
醫學研究所
89
Plantago major Linn. (P. major) and Plantago asiatica Linn. (P. asiatica), are traditional Chinese herbal remedy and have been used to prevent breast cancer, conjunctivitis, hepatitis in Taiwan for hundreds of years. However, the mechanism of anti-tumor and anti-virus on both plants is still unclear. In the present study, the water crude extracts of P. major, P. asiatica and twelve related pure compounds were examined on various of herpesviruses, adenoviruses, leukemia and carcinoma cells. Results showed that P. major extract, P. asiatica extract, baicalin, and linalool are most active by various biological assays. The IC50 of linalool on HeLa cells was 0.37μg/ml. The SI of linalool, chlorogenic acid and caffeic acid were 5621, 300.6 and 726.9, respectively. The ED50 of chlorogenic acid and caffeic acid on ADV-11 and ADV-3 were 13.29μg/ml and 14.16μg/ml, respectively. For all pure compounds, only luteolin did not show immunostimulatory activity. Others directly enhanced DNA synthesis and increased IFN-γsecretion of PBMC. Especially, 20μg/ml of oleanolic acid and 40μg/ml of ursolic acid induced 258 pg/ml and 203 pg/ml, respectively, of IFN-γsecretions from PBMC. The brosd-spectrum of anti-leukemia, anti-carcinoma, anti-virus and increase in cell-mediated immunity of these test materials indicated a great potential in use of viral infection treatment and cancer therapy. Further study is necessary to understand the action mechanism of these test materials.
42
Kuo, Li-Chen, та 郭力禎. "Pure compounds TR and AG within Chinese herbal medicines mediate glutamate receptors to attenuate Aβ-induced neuronal pathophysiology". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/j54snt.
43
Ying, Jau-Wen, and 尹照雯. "Anti-enterovirus 71 activity and mechanism of Ge-Gen-Tang and its related pure compounds of Cinnamomum cassia." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/93855987117719325491.
Анотація:
碩士高雄醫學大學
醫學研究所
97
Abstract Enterovirus 71 (EV71) is endemic spread all of the year in the world. There is still no effective agent and vaccine could be used. In this study, we wanted to seek potential herbal candidate to prevent EV71 infection. Ge-Gen-Tang (GGT) is a traditional Chinese herbal remedy and commonly used to treat infectious disease including common cold. GGT has been found to be active against influenza virus, herpesvirus type 1, and EV71. Therefore, we tested the GGT and its related ingredients, Cinnamomum cassia Blume against EV71 by XTT reduction assay. The results showed that IC50 of the crude extracts of GGT and C. cassia against EV71 infection were 0.93 ± 0.01 μg/ml and 1.70 ± 0.21 μg/ml, respectively. The selectivity index (SI: CC50/IC50) of GGT and C. cassia were larger than 3000 and 294, respectively. These results indicated that GGT and C. cassia were effective (low IC50 value) and safe (high SI value) against EV71. The result of time course assay indicated that GGT and C. cassia exhibited their anti-EV71 activity both before and after EV71 infection. Therefore, they had both preventive and therapeutic potential. Later, we proved the effective pure pompounds of C. cassia to be trans-cinnamic acid, cinnamaldehyde, cinnamyl acetate, benzaldehyde, cuminaldehyde, vanillin, 2-methoxycinnamic acid, and 2-methoxycinnamaldehyde. Their IC50 against EV71 of benzaldehyde, cuminaldehyde, 2-methoxycinnamaldehyde, cinnamaldehyde, vanillin, 2-methoxycinnamic acid, cinnamyl acetate, and trans-cinnamic acid against EV71 infection were 0.21 ± 0.01 μM, 0.89 ± 0.04 μM, 0.94 ± 0.15 μM, 1.57 ± 0.05 μM, 1.65 ± 0.39 μM, 10.06 ± 2.01 μM, 27.73 ± 4.14 μM, and 34.36 ± 0.89 μM, respectively. The selectivity indexes (SI: CC50/IC50) of benzaldehyde, vanillin, cuminaldehyde, 2-methoxycinnamaldehyde, cinnamaldehyde, 2-methoxycinnamic acid, trans-cinnamic acid, and cinnamyl acetate were 13128.57, 1575.50, 1245.88, 162.14, 99.08, 94.58, 39.35, and 34.07 respectively. Our results revealed several novel anti-EV71 agents, such as benzaldehyde, cuminaldehyde, cinnamaldehyde, vanillin, and 2-methoxycinnamaldehyde. In order to understand the anti-EV71 mechanisms, we had time course assay, attachment assay, and interferon assay. The results of time course assay showed that benzaldehyde, cuminaldehyde, and cinnamaldehyde exhibited their anti-EV71 activity before and after EV71 infection. Therefore, all of these agents had preventive and therapeutic potential. The results of attachment assay and penetration assay of Benzaldehyde showed that the IC50 against EV71 attachment activity was 0.55 ± 0.39 μM. Its IC50 against EV71 penetration activity after 10min~60min treatment ranged from 0.07 ± 0.01 μM to 0.21 ± 0.03 μM, respectively. Benzaldehyde did not stimulate interferon production. Therefore, its anti-EV71 activity was not mediated by interferon. Our results have proven that GGT, C. cassia and several its pure compounds are effective to manage EV71 infection by inhibiting EV71 induced cytotoxicity, by inhibiting viral attachment and/or penetration. Our results could be helpful to develop effective anti-EV71 agents.
44
Chiu, Hung-Chih, and 邱泓智. "Anti-Alzheimer’s disease potential of extracts of Agaricus blazei and several pure compounds in PC-12 cell model." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/91527434602267018577.
Анотація:
碩士國立臺灣大學
食品科技研究所
97
Alzheimer’s disease (AD) is the most common form of dementia caused by accumulation of amyloid-beta (Aβ) peptide in the brain, leading to elevated oxidative stress, inflammation, and neuronal loss in the brain. PC-12 cells, a neuronal-like cell line, were treated with Aβ to simulate the toxicity of Aβ towards neuron cells in AD. Several samples with high antioxidative activity including gallic acid, proanthocyanidin A2, arachidin-1, and sesamol, which is able to pass through the blood-brain-barrier (BBB), and samples with immunomodulating activities including tetrahydrocurcumin, Agaricus blazei, were used in Aβ treated PC-12 cells to evaluate the potential of these samples in the prevention of AD. Several methods for the preparation of toxic aggregates of Aβ1-40 fragment failed to exhibit significant toxicity towards PC-12 cells. The shorter active fragment Aβ25-35 was used instead, and H2O2 was also applied to mimic the elevated oxidative stress observed in neurons treated by Aβ. Result showed that differentiated PC-12 cells formed neurites and were more sensitive to toxicity of samples, but more resistance towards oxidative stress induced by H2O2. Both proanthocyanidin A2 and arachidin-1 exhibited protective effect in naïve PC-12 cells towards both Aβ25-35 and H2O2 damage. Ethanol and water extracts of A. blazei did not protect naïve PC-12 cells from Aβ25-35 toxicity, but was effective in protection of H2O2 damage. However, all the samples failed to protect differentiated PC-12 cells from H2O2 insult. Of the pure compound used, gallic acid, tetrahydrocurcumin, proanthocyanidin A2, arachidin-1 all exhibited stronger DPPH scavenging ability than trolox, followed by sesamol and α-tocopherol, with the extracts of A. blazei exhibiting poor scavenging abilities. The results suggest that proanthocyanidin A2, arachidin-1 exhibited protection against Aβ25-35 in naïve PC-12 cells, possibly by decreasing the elevated oxidative stress caused by Aβ25-35. Ethanol and water extracts of A. blazei were poor in DPPH scavenging ability yet protected naïve PC-12 cells from H2O2, implicating mechanism of actions other than direct antioxidative activity.
45
Chiu, Kun-Yuan, and 裘坤元. "The Effects and Underlying Mechanisms of the Pure Compounds Isolated from Antrodia cinnamomea on Human Urinary Tract Malignancies." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/70139918695148538856.
Анотація:
博士朝陽科技大學
應用化學系
104
Antrodia cinnamomea, a famous medicinal mushroom, known as Niuchang chih in Taiwan, exhibits anti-inflammatory, anti-oxidative, anti-angiogenic and hepatic protection properties. Several in vitro studies demonstrate the anti-cancer effects of Antrodia cinnamomea on hepatoma, lung cancer, as well as breast cancer. In this study, the effects of two active compound, Antrocin and Antcin H isolated from Antrodia cinnamomea against urological malignancies, both bladder cancer and renal cell carcinoma (RCC) were examined. Our study showed that treatment with cytotoxic concentration of Antrocin induced both intrinsic and extrinsic apoptotic pathways in human bladder cancer 5637 cells, evidenced by increase of Fas, DR5, Bax expression and caspase-3, -8 and -9 activation. Exposure to non-cytotoxic concentrations of antrocin significantly inhibited cell growth, migration, and invasion, which was associated with decreased phosphorylation of focal adhesion kinase (FAK) and paxillin. Antrocin also reduced subcellular distribution of FAK and paxillin at the focal adhesion contacts of the cell periphery site, and disrupted the formation of filopodia and lamellipodia. Moreover, Antrocin increased epithelial-to-mesenchymal transition-related gene E-cadherin and decreased vimentin expression. Real time-PCR analysis showed that Antrocin downregulated the expression of mRNA of several matrix metalloproteinases (MMPs), including MMP-2. Also, the phosphorylation of ERK and c-Fos were attenuated by Antrocin. Data from chromatin immunoprecipitation assay demonstrated that antrocin decreased the DNA binding activity of c-Fos to the upstream/enhancer region of MMP-2 promoter, an action likely to result in reducing MMP-2 expression. Next, the anti-cancer effects of antcin H were investinged in human renal carcinoma 786-0 cells. The results showed that antcin H significantly inhibited the growth of RCC 786-0 cells, the IC50 value (for 48 h) of antcin H was 170 μM. Besides, the migration and invasion of 786-0 cells were also drastically suppressed by antcin H under non-cytotoxic concentrations (< 100 μM), these events were accompanied by the inhibition of FAK and Src kinase activities, decreases of paxillin phosphorylation and vimentin expressions, impairment of focal contact and lamellipodium formation, and up-regulation of tissue inhibitor of metalloproteinases (TIMPs) as well as down-regulation of several MMPs, especially MMP-7 expression. Data from the reporter luciferase assay showed that antcin H repressed the MMP-7 promoter activity, in parallel to inhibition of c-Fos/AP-1 and C/EBP-β transactivation properties. Moreover, antcin H strongly suppressed the activity of ERK1/2 and decreased the binding ability of C/EBP-β and c-Fos on the upstream/enhancer region of MMP-7 promoter. Overall, this is the first study demonstrates that Antrocin inhibited the migration and invasion of bladder cancer cells as well as the anti-migratory and anti-invasive effects of the Antcin H on RCC 786-0 cells. Our findings provide the evidence that Antrocin may be the substitutional therapy of bladder cancer, while Antcin H may have the potential for application on treating metastatic RCC.
46
Liu, Ya-Wei, and 劉亞薇. "Studies of Herbal Pure Compounds Tanshinone IIA and Osthole against Hepatic Fibrosis in Rats and Hepatic Stellate Cell Activation." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/84044215206360952234.
Анотація:
博士國立陽明大學
傳統醫藥研究所
103
Hepatic fibrosis is a dynamic process which ultimately leads to cirrhosis in many patients with chronic hepatic injury. However, progressive fibrosis is a reversible scarring response. Preventing activation and inflammation of hepatic stellate cells (HSCs) is the major strategy to treat hepatic fibrosis. Clinical therapies for hepatic diseases remain unsatisfactory. In the present studies, two approaches were used to investigate the potentials of Traditional Chinese Medicines (TCM) in treating hepatic fibrosis and HSC activation. Previously, our group has taken years to study Salvia miltiorrhiza Bae. (S. miltiorrhiza) which is a common herb used in the prescriptions of treating hepatic disease. It was found that Sal B exerts inhibitory ability in HSC activation and hepatic injury. I attempted to explore whether the Tanshinone IIA (Tan IIA, C19H18O3, MW = 294.34), one of lipophilic diterpene, in S. miltiorrhiza could inhibit HSC activation. Another approach in our lab was that we screened hundreds pure compounds isolated from herbs, we discovered that osthole, an active component contained in the fruit of Cnidium monnieri (L.) Cusson (C.monnieri (L.) Cusson), could inhibit HSC activation effectively in preliminary screening. Therefore, I further conducted both in vitro and in vivo studies to investigate the therapeutic effects of osthole on rat liver fibrosis and HSC activation. We used lipopolysaccharide (LPS) (100 ng/ml) to stimulate rat hepatic stellate cells (HSC-T6). Tan IIA (10 uM) was used to inhibit LPS-induced HSC activation and compared with Sal B (200 uM). All concentrations of Tan IIA (1 to 10 uM) and Sal B (200 uM) showed no cytotoxicity against HSC-T6 cells. LPS stimulated NF-κB luciferase activities, nuclear translocation of NF-κB-p65, and phosphorylations of ERK, JNK and p38, were suppressed by Tan IIA. In addition, Tan IIA significantly inhibited LPS-induced HSCs chemotaxis, in both wound-healing and trans-well invasion assays. Moreover, Tan IIA attenuated LPS-induced mRNA expressions of CCL2, CCL3, CCL5. Furthermore, Tan IIA also attenuated LPS-induced fibrosis-related mRNA expressions, including IL-1, TNF-, iNOS, ICAM-1, and IL-6. In addition, the protein and gene expression of a-SMA were both downregulated by Tan IIA in HSC-T6 cells. For the investigation of osthole (C15H16O3, MW = 244.29), I established the thioacetamide (TAA)-model of Sprague-Dawley (SD) rats to induce hepatic fibrosis. Rats were divided into three groups: control, TAA, and TAA + osthole (10 mg/kg). In vivo, osthole significantly reduced liver injury by diminishing levels of plasma AST and ALT, improving histological architecture, decreasing collagen and a-SMA accumulation, and improving hepatic fibrosis scores. Additionally, osthole reduced the expression of fibrosis-related genes significantly. Osthole also suppressed the production of fibrosis-related cytokines and chemokines. Moreover, nuclear translocation of p65 was significantly suppressed in osthole-treated liver. Osthole also ameliorated TAA-induced injury through reducing cellular oxidation. Osthole showed inhibitory effects on inflammation-related genes and chemokine production as well. In vitro, we assessed osthole effects in activated HSCs (HSC-T6 and LX-2). Osthole (10 ug/ml) attenuated TGF-b1-induced migration and invasion in HSCs. Furthermore, osthole decreased TNF-a-triggered NF-κB activities significantly. Besides, osthole attenuated TGF-b1- or ET-1-induced HSC contractility. Our results demonstrated that Tan IIA decreased LPS-induced HSC activation. In addition, osthole improved TAA-caused liver injury, fibrogenesis and inflammation in rats, and significantly suppressed HSCs activation in vitro. According to the study results, Tan IIA from S. miltiorrhiza could inhibit HSC activation, and osthole from C.monnieri Cusson could improve rat liver injury and also attenuate HSC activation. This thesis provides the evidences for using S. miltiorrhiza and C.monnieri (L.) Cusson in the clinical and the academic of TCM.
47
Tzu-Ya and 吳慈雅. "Inhibitory effect of the pure compounds existing in plant polyphenols on high glucose induced human retinal pigment epithelial cell proliferation." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/67405674735402344418.
Анотація:
碩士中山醫學大學
生化暨生物科技研究所
96
High level of blood glucose could produce reactive oxygen species (ROS) to cause retinopathy. Our previous study demonstrated that Hibiscus sabdariffa aqueous extracts (HSE) and Hibiscus sabdariffa polyphenols extracts (HPE) could decelerate retinopathy in streptozotocin (STZ)-induced diabetic rats. In this study, we further examined the effect of protocatechuic acid, catechin, ferulic acid, gallic acid, quercetin and epicatechin existing in HSE in high glucose treating human retinal pigment epithelial (RPE) cells. We found that after treatment of high glucose (25 mM) for at least 6 days, RPE cells showed a significant increase in a dose-dependent manner. As accompanied with treatment of 10μM concentration of protocatechuic acid, quercetin, ferulic acid, catechin, gallic acid and epicatechin the increased cell could be reduced up to 51.78%, 37.4 %, 30.27 %, 30.07 %, 22.93%, 32.47%, respectively. We further examined the expressions of PKC-α, PKC-δ, PKC-λ. But, there were no significant changes in these proteins. We examined that after treatment of high glucose (25 mM) for 48 hrs, RPE cells showed the activity of MMP-2 significant increase.As accompanied with treatment of10μM concentration of protocatechuic acid, quercetin and ferulic acid the increased MMP-2 activity could be reduced to 25.9%, 14.8%, 5.9%, respectively. In conclusion, protocatechuic acid、quercetin、ferulic acid、catechin、gallic acid and epicatechin could reduce high glucose induced RPE cell proliferation, but the mechanisms should be further clarified.
48
"Part I. Synthetic studies of furanosesquiterpenoid tetrahydrolinderazulenes. Total synthesis of (plusmn)-echinofuran, and, Part II. Synthetic applications of chiral furyl boronates. Asymmetric synthesis of optically pure substituted furylamines." 2003. http://library.cuhk.edu.hk/record=b6073597.
Анотація:
"July 2003."Thesis (Ph.D.)--Chinese University of Hong Kong, 2003.
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Mode of access: World Wide Web.
Abstracts in English and Chinese.
49
Yang, Chien-Min, and 楊蒨旻. "The Study of Anti-Herpes Simplex Virus Activity and the Mode of action of Extracts and Pure Compounds Isolated from Phyllanthus urinaria L." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/09416854339698237698.
Анотація:
博士高雄醫學大學
藥學研究所
96
The fewer applicable of antiviral medicine, the emergence of resistant viruses, etc make a desire of searching new effective agent to manage viral infection. In this study, some extracts and pure compounds of Phyllanthus urinaria L. (Euphorbiaceae) were investigated for in vitro anti-HSV-1 and HSV-2 activities by plaque reduction assay. Results showed that the acetone, ethanol and methanol extracts inhibited HSV-2 infection more significance than that of HSV-1. All the three extracts showed more than 92.7% inhibiton against HSV-2 infection at concentration of 100 μg/ml. The time of addition study demonstrated that these three extracts only effective when added during the HSV-2 infection which suggested that they might disturb the initial stage of HSV-2 infection. Furthermore, they can diminish virus infectivity without significantly affecting by incubation time and temperature. Nine pure compounds isolated from P. urinaria were tested for antiviral activity and were found to inhibit HSV replication at different magnitudes of activity. Among them, euphorbin D and excoecarianin had good antiviral activity. Besides, both compounds also had high selectivity index, which served them as the candidates for the following mechanism studies. The results showed that excoecarianin could significantly diminish virus iv infectivity at concentration of IC50, while euphorbin D needed high concentration to achieve the same effect. Euphorbin D was also been found to inhibit HSV-2 from attaching to cell membrane, and prevented HSV-2 from penetrating into cells. However, it can not detach those viruses which had been bound to cells. Euphorbin D, dependent with the used concentrations, acted either synergistically or subsynergistically with ACV in suppressing HSV-2 multiplication. In summary, the extracts and pure compounds of P. urinaria were found to inhibit HSV infection at different magnitudes of activity through different modes of action. The inactivation of virus infectivity at low concentration, and the synergistical or subsynergistical action between euphorbin D with ACV on inhibiting HSV infection, were merits for further investigation.
50
Chun-KueiChen and 陳俊貴. "Streamwise Interaction of Burning Pure/Compound Drops." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/05572285389039370702.
Анотація:
博士國立成功大學
機械工程學系碩博士班
100
The spatial distribution of drops and the consequential interactions are influential parameters in spray combustion. Most of the available research papers on this subject were about lateral spacing effects or were performed in microgravity. Studies about upstream/downstream convective interaction of burning drops are scarce. In this study, single-component or compound drop strings of different spacing were observed in a high-temperature oxidizing environment for their flame transition, flame width variation and drop evaporation rate. As the drop fell into the combustion chamber, due to the acceleration of the drop and the deceleration of the gas the drop flame initially appeared below the drop. The flame became a spherical envelope flame, and later moved behind the drop and burned as a wake flame. It was found that a drop string with an initial drop spacing (Si) of 2.5 or 5 was surrounded by a bulk flame tube, exhibiting characteristics of group burning and soot layer. In addition, for the case of Si=2.5, spacing instability and collision merging of the burning drops occurred. For other cases, most of the drops were not surrounded by flame. For the case of Si 〈 30, the drop evaporation rate was lower than that of a single drop. For the case of 30 〈 Si 〈 75, the drop evaporation rate was higher than that of a single drop. The interaction of drops diminished if Si was more than 75. The results of the experiments on compound drops indicated that in general the flame length increased as the initial drop spacing (Si) decreased. However, for a drop string with an initial spacing about 2.5, the trend reversed due to collision-merging of the drops. Micro-explosion occurred because of nucleation bubble explosion in the water core of the compound drop. The flame spread through micro-explosion occurred for the case of Si = 10, and the effect of spacing on drop evaporation diminished beyond Si = 30.