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1
Szecsödy, James Edward. "Sorption Kinetics of Hydrophobic Organic Compounds onto Organic Modified Surfaces." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/219433.
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The sorption of five chlorinated benzenes and sixteen other organic solutes was investigated by determining the extent of sorption and the sorption rates in a series of 40 batch and 139 column experiments using surface-modified silica of known chemical composition. These surfaces were used to represent important functional groups in soil, and consisted of porous silica with patchy surface coatings of aliphatic chains (C₁, C₈, and C₁₈), and other substituent groups (phenyl, amine, alcoholic, and carboxylic). Three possible rate-limiting steps were examined: diffusion through immobile pore fluid, diffusion through bound organic matter, and the chemical binding and release rate. First-order desorption rate coefficients were observed to be 10⁻¹ to 10⁻² s⁻¹ on unbonded, and C₈, C₁₈, amine, and alcoholic modified surfaces, and 10⁻³ to 10⁻⁵ s⁻¹ on C₁ and phenyl-polymer modified surfaces. Diffusion through immobile pore fluid had only a minor effect on the sorption rate, as evidenced by similar rates on organic-bound porous and solid particles. The diffusion rate through the bound organic layer is not rate limiting due to the small organic layer thickness. The observed slow desorption on the phenyl-polymer surface is consistent with the rate limiting step being the chemical binding and release rate. The changes in the rate with temperature and within a series of chlorinated benzenes support this conclusion. The free energies for sorption onto the phenyl-polymer surface ranged from -4.0 kcal mol⁻¹ for chlorobenzene to -6.9 kcal mol⁻¹ for pentachlorobenzene, which are within the range expected for van der Waals interactions. The observed sorption energies are slightly stronger than predicted for hydrophobic surfaces, possibly reflecting strong binding due to multiple pi-pi electron interactions on the phenyl-polymer surface. Hydrophobic solute partitioning onto natural soils, as observed by others, is less than that observed on aliphatic and phenyl hydrophobic surfaces in this study, but greater than on amine or alcoholic modified surfaces. The sorption of di-, tri-, and tetra-chlorobenzenes onto the phenyl-polymer surface is apparently driven by the overall sorption enthalpy (ΔH° = -3.9 to -4.9 kcal mo1⁻¹) and to a lesser extent by the entropy (TΔS° = 0.5 to 1.5 kcal mol⁻¹). As equilibrium of the reactions observed in this study are reached within hours, these reactions are important at small field scales where residence times are hundreds of hours or less.
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Wu, Shian-chee. "Transport of hydrophobic organic compounds between water and natural sediments." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/15099.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1986.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
Bibliography: leaves 159-168.
by Shian-chee Wu.
Ph.D.
3
Morris, Kenneth Robert 1951. "THE SOLUBILITY OF HYDROPHOBIC POLLUTANTS IN WATER-COSOLVENT MIXTURES." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/276659.
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Bruant, Robert Gilbert. "Adsorption of volatile hydrophobic organic compounds at the vapor/water interface." Diss., The University of Arizona, 2000. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_2000_292_sip1_w.pdf&type=application/pdf.
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Mohseni, Tonekaboni Madjid. "Biofiltration of hydrophilic and hydrophobic volatile organic compounds using wood-based media." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0014/NQ35255.pdf.
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Badea, Silviu-Laurentiu. "Association of hydrophobic organic compounds to organic material in the soil system." Licentiate thesis, Umeå universitet, Kemiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-68378.
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Contaminated soils and sediments have been identified as significant secondary sources of organic contaminants. Leaching tests may be useful tools to estimate the mobility of contaminants via the water phase and thereby the risk for groundwater and surface water contamination. The influence of soil composition (peat and clay content) on the leachability was investigated in batch leaching experiments for chemically diverse hydrophobic organic compounds (HOCs: PCP, PAHs, HCB, HCHs, PCBs, and TCDD/Fs). The above mentioned compounds were analyzed by both GC-LRMS (gas chromatography coupled with low resolution mass spectrometry (GC-HRMS) and GC-HRMS (gas chromatography coupled with high resolution mass spectrometry). Also the the leachability of eleven selected PCBs from naturally aged soil (Västervik, Sweden) was investigated in relation to the composition and concentration of dissolved organic matter at different pH (2 to 9), using a pH static test with initial acid/base addition. The the composition and of dissolved organic matter (DOM) at different pH values was explored by FTIR spectroscopy. The results were evaluated by orthogonal projections to latent structures (OPLS). Generally, for all model compounds studies, the Kd-values showed a variability of 2-3 orders of magnitude depending on the matrix composition. The Kd-values of moderately hydrophobic compounds, (e.g. HCHs, PCP and Phe), were correlated mainly with the organic matter content of soil. For more hydrophobic compounds (e.g.BaA, HCB and PCB 47), the leachability decreased as the proportions of OM and clay contents increased. The Kd-values of 1,3,6,8-TCDD and 1,3,6,8-TCDF were positively correlated with peat content but negatively correlated with clay content, while for PCB 153 and PCB 155 the correlations were reversed. The log Kd-values of all target PCBs decreased with increased pH values and the log Kd-values were highly correlated with the concentration of total organic carbon (TOC) in the leachates. The FTIR analysis of DOM showed that the least chlorinated and hydrophobic PCB congeners (i.e. PCB 28) might be associated with the hydrophilic fraction (i.e. carboxylic groups) of DOM. Our study demonstrated how complex interaction between the organic matter, clay components, pH and DOC influences the leachability of HOCs in a compound-specific manner.
7
Wee, Hun Young. "Remedial extraction and catalytic hydrodehalogenation for treatment of soils contaminated by halogenated hydrophobic organic compounds." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1280.
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Zehraoui, Abderrahman. "ENHANCED BIOLOGICAL OXIDATION OF HYDROPHOBIC COMPOUNDS UNDER DYNAMIC LOAD IN A TRICKLE BED AIR BIOFILTER." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1384849490.
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Pan, Wubin. "Regulation of the susceptibility of Neisseria gonorrhoeae to antibiotics and hydrophobic compounds by the mtr system." Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238975.
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Jakubowska, Joanna. "Effect of irrigation water type on soil organic matter (SOM) fractions and their interactions with hydrophobic compounds /." Leipzig : UFZ, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015692639&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Barnier, Claudie. "Biodiversité et fonctionnalité des biofilms oléolytiques en milieu marin." Thesis, Pau, 2018. http://www.theses.fr/2018PAUU3032/document.
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En milieu marin le carbone organique particulaire (POC) représente 25 % du carbone organique total. Sa dégradation est réalisée par des microorganismes hétérotrophes ayant mis en place diverses stratégies pour parvenir à le dissoudre et l’assimiler. Peu d’études se sont intéressées à la dégradation des composés polymériques et/ou hydrophobes, quasiment insolubles dans l’eau constituant le POC. Parmi ces composés, on retrouve les lipides et les hydrocarbures regroupés sous le terme de COH (composés organiques hydrophobes). La dégradation des COH est réalisée par des bactéries dîtes oléolytiques ayant entre autre pour stratégie la formation de biofilms également qualifiés d’oléolytique. Nos connaissances sur la diversité et la fonctionnalité des biofilms oléolytiques se limitent actuellement aux bactéries spécifiquement étudiées pour leur capacité à dégrader les HC. Ainsi la dégradation des lipides est souvent négligée alors que cette famille de molécules représente une part significative du POC.La diversité taxonomique des bactéries formant des biofilms oléolytiques a été déterminée par un criblage de 199 souches marines sur 4 substrats : un alcane (paraffine), un triglycéride (tristéarine), un acide gras (acide palmitique) et une cire (l’hexadécyl palmitate). Cette étude a révélé que les bactéries oléolytiques (formant un biofilm sur au moins 1 des substrats) sont relativement répandues parmi les bactéries marines puisque qu’elles représentent 18.7 % des souches testée. Cette étude montre également que les bactéries capables d’assimiler les alcanes sont également capables d’assimiler au moins un lipide. Les bactéries hydrocarbonoclastes, jusqu’alors décrites comme spécialisées, voir restreintes à l’assimilation des hydrocarbures, présentent donc une gamme de substrats s’étendant aux lipides. La corrélation positive entre la capacité d’assimilation des alcanes et l’assimilation des lipides suggère un lien physiologique entre l’assimilation de ces deux familles de COH. L’activité lipase qui est essentielle à l’assimilation des triglycérides mais pas à l’assimilation des alcanes, a été mesurée dans des cultures de souches oléolytiques poussant sur acétate, triglycéride ou hexadécane. Comme attendu, les cultures sur triglycérides montrent toutes une surexpression de l’activité lipases par rapport aux cultures sur acétate. Les cultures sur hexadécane montraient aussi une surexpression de l’activité lipase renforçant l’idée d’un lien physiologique entre dégradation des alcanes et dégradation des lipides. De plus les souches oléolytiques n’ont pas montré de capacité à former un biofilm sur une surface inerte hydrophobe telle que le polystyrène ou sur une surface hydrophile telle que le verre à la hauteur de celles constaté sur COH. Une étude quantitative de l’adhésion sur COH et substrats inertes réalisée par microscopie montre que l’adhésion (dans les conditions testées) n’est pas un facteur déterminant de la formation de biofilm sur ces mêmes substrats. Cela suggère que la spécificité de formation de biofilm sur les substrats COH, ne réside pas dans l’adhésion mais vraisemblablement dans les étapes de développement du biofilm plus tardives.Enfin, les biofilms oléolytiques mettant en jeux des produits extracellulaires (enzymes et facteurs de solubilisation) qui constituent des biens communs, sont propices à l’établissement de comportements sociaux. Nous avons mis en évidence des comportements synergiques (5/8 des comportements observés) ou compétitifs au sein de biofilm oléolytiques (3/8 des comportements observés)Particulate organic carbon (POC), in marine environment, accounts for 25% of total organic carbon. POC degradation is carried out by heterotrophic microorganisms which have developed strategies to dissolve and assimilate it. Few studies have investigated the degradation of the polymeric and / or hydrophobic components of POC, which are almost insoluble in the water. Among these compounds, there are lipids and hydrocarbons (HC) grouped under the term of HOCs (hydrophobic organic compounds). The degradation of the HOCs is carried out by oleolytic bacteria which form biofilms at the HOC– water interface. Our knowledge of the diversity and functionality of oleolytic biofilms is mostly limited to HC degrading bacteria, while the degradation of lipids is often neglected although this family of molecules represents a significant part of the POC. A screening of 199 marine strains on 4 substrates: an alkane (paraffin), a triglyceride (tristearin), a fatty acid (palmitic acid) and a wax ester (hexadecyl palmitate) was performed to determine the taxonomic diversity of bacteria able to form oleolytic biofilms. This study revealed that oleolytic bacteria (forming a biofilm on at least 1 substrate) were relatively widespread among marine bacteria since they represented 18.7% of tested strains. This study also showed that bacteria able to assimilate alkanes were also able to assimilate at least one lipid. Hydrocarbonoclastic bacteria, previously described as specialized, or restricted to the assimilation of hydrocarbons, have actually a substrate range spanning from HC to lipids. The positive correlation between the ability to form a biofilm on alkanes and on lipids suggested a physiological link between the assimilation of these two HOC families. The lipase activity, which is essential for triglycerdides assimilation but not for the alkanes assimilation, was measured in oleolytic strains cultures growing on acetate, triglyceride or hexadecane. As expected, overexpression of lipase activity was observed in cultures on triglycerides compared to cultures on acetate. Moreover, overexpression of lipase activity was also observed in cultures on hexadecane reinforcing the idea of a physiological link between alkanes and lipids degradation.Oleolytic strains exhibited a very weak ability to form a biofilm on the inert surfaces (non-nutritive) polystyrene or glass compared to the HOC nutritive surface indicating that oleolytic strains have a specificity for HOC to form a biofilm. A quantitative study of adhesion on HOC and inert substratums carried out by microscopy shows that adhesion (in the tested conditions) is not a determining factor of the biofilm formation on these same substrates. This suggests that the specificity of biofilm formation on HOC substrates does not reside in adhesion but presumably in later biofilm development stages.Lastly, oleolytic biofilms, involving extracellular products (enzymes and solubilization factors) that constitute public goods, are favorable to the establishment of social behaviors. We have demonstrated synergistic behaviors (5/8 of observed behaviors) or competitive behaviors (3/8 of observed behaviors) in oleolytic biofilms
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Gonzalez, Ricardo Rene. "Fundamental studies in the solid-phase extraction of organic cations and neutral compounds: The role of hydrophobic and ionic interactions." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/279853.
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The work presented is a systematic investigation of silica-based sorbents using solid-phase extraction (SPE). Properties of various cation exchangers and mixed beds comprised of strong cation exchange particles and alkyl-modified silica particles were explored. The role of ionic and nonpolar interactions was examined in terms of retention and elution of analytes. A series of displacement experiments was used to characterize the interactions and energy-minimized, three-dimensional models were used to illustrate these interactions. Selectivity of cation exchangers was probed by introducing cations differing in size, hydrophobic nature and charge before and after introduction of the analytes. The ionic strength, the solvent composition and the pH of the liquid phase were parameters that were varied in order to define the type of interaction that was responsible for retention, lack of retention, or elution during the SPE procedure. Application of mixed sorbents toward the extraction of basic drugs of abuse, as well as the use of reversed-phase silica and a resin for the extraction of a neutral organonitrogen species were also investigated. With propylene-linked cation exchangers (under appropriate pH conditions), it was shown that the primary mode of interaction is through ionic forces. As a consequence, there is no selectivity of these sorbents for cations based on hydrophobic nature. With ethylbenzene and octylene-linked exchangers, there is an increase in selectivity for cations with increasing hydrophobic nature. The linker chain is adequately long enough to allow for nonpolar interactions with the aliphatic side groups, just as a resin-based exchanger allows. With short and long chain exchangers, there is selectivity proportional to the charge of the ion. The proposed reason for this is a combination of multiplesite attachment of polyprotic species to the surface and increased probability of single-site interaction proportional to the number of charged nitrogen atoms on the molecule. It was shown that mixed sorbent beds offer advantages in operator control over the retention of organic bases in a high ionic strength sample matrix. The retention mechanism was elucidated, demonstrating a clear contribution of nonpolar forces to retention with the mixed sorbents as was observed with the long-chain cation exchangers.
13
Rehmann, Lars. "Delivery of hydrophobic substrates to degrading organisms in two-phase partitioning bioreactors." Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/506.
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Zhang, Yanling. "Hydrophobic organic compounds (HOCs) and algal derived organic materials (AOM) in drinking reservoirs around the Pearl River Delta Region : effects of chlorination and protecting effects of dietary antioxidants against genotoxic disinfection byproducts (DBPs)." HKBU Institutional Repository, 2012. https://repository.hkbu.edu.hk/etd_ra/1403.
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Bosch, Tanya. "Development of a degreasing and anti-fogging formulation for wet wipe application for automotive glass surfaces." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1013177.
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It was the objective of this project to provide a glass cleaner formulation for a wet wipe application with cleaning and anti-fogging properties. This glass cleaner formulation was developed for automotive glass i.e. interior of windscreens. This formulation relates to a glass cleaner with a composition comprising of: (a) a blend of amphoteric surfactants; (b) a solvent system with a combination of glycol ethers; and (c) an aqueous solvent system. This glass formulation must provide good cleaning properties while also providing good wetting and sheeting properties to assist with anti-fogging properties. The objectives were obtained using 2 specific approaches: The first was by using a blend of 2 amphoteric surfactants in an alkaline medium, allowing the glass surface to become more hydrophilic which will also assist with reduction of surface tension on the glass surface. The second was by using the glycol ethers that have good coupling properties and surface tension reducing properties. The formulation was evaluated using commercial standard test methods as per the industry. A predictive model was successfully obtained for each of the five criteria that were evaluated using the 25 formulations derived from the statistical design. There were variables and variable interactions that were antagonistic for some of the criteria which were found to be synergistic for others. To achieve satisfactory cleaning, the fogging rating had to be compromised.
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Mounier, Julie. "Caractérisation fonctionnelle de gènes de Marinobacter hydrocarbonoclasticus lors du développement de biofilms sur composés organiques hydrophobes." Thesis, Pau, 2013. http://www.theses.fr/2013PAUU3017/document.
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Les composés organiques hydrophobes (HOCs), lipides et hydrocarbures, représentent une part significative de la matière organique dans l’environnement marin. Leur faible solubilité dans l’eau exige de la part des bactéries qui les dégradent des adaptations physiologiques permettant de stimuler leur transfert de masse de la phase organique vers la phase aqueuse où ils sont assimilés. La formation de biofilm à l’interface HOC-eau est l’une de ces adaptations. La bactérie marine Marinobacter hydrocarbonoclasticus (Mh), qui est capable d’utiliser un catalogue assez large de HOCs comme les alcanes, les alcools gras et les triglycérides, a été utilisée comme modèle d’étude de la formation de biofilms aux interfaces HOCs-eau. Le but de mes recherches était de : (i) mener la caractérisation fonctionnelle des gènes aupA et aupB, qui sont surexprimés en condition de biofilm sur hexadécane et (ii) dresser, par une étude de transcriptomique, une liste de gènes potentiellement impliqués dans l’adhésion et la formation de biofilm aux interfaces HOCs-eau dans le but d’appréhender les mécanismes moléculaires mis en jeu. L’étude fonctionnelle de aupA et aupB a révélé que ces deux gènes forment un opéron dont l’expression est activée par divers types de HOCs. Il a aussi été démontré qu’ils sont impliqués dans le transport de l’hexadécane et dans la formation de biofilm sur alcanes. La protéine AupA est localisée dans la membrane externe de Mh et AupB, une lipoprotéine présumée, est située dans la membrane interne. AupA appartient à une sous-famille de transporteurs FadL-like, spécifique des bactéries marines hydrocarbonoclastes (HCB). La distribution phylogénétique de l'opéron aupAB limitée aux bactéries marines ayant la capacité de dégrader les alcanes et sa présence en nombreuses copies chez certaines souches d’Alcanivorax sp. suggèrent fortement que les protéines Aup joueraient un rôle primordial dans l’adaptation des HCB à l’utilisation d’alcanes comme sources de carbone et d’énergie. L’analyse transcriptomique des cellules de Mh adhérées (après 15 min ou 3 h de contact) ou formant un biofilm aux interfaces HOCs-eau a révélé une modification importante et précoce de leur transcriptome. De nombreux gènes intervenant dans le métabolisme des HOCs, la production de polysaccharides, la synthèse d’acides aminés et de protéines ribosomales présentent une expression modulée dès 15 min d’adhésion. La surexpression des gènes de flagelle et du chimiotactisme conjointement avec celle de gènes de pili en condition d’adhésion évoquent une possible mobilité des cellules de Mh à l’interface dans les étapes précoces du développement du biofilm. De plus, il semblerait que le facteur de transcription RpoN soit impliqué dans la régulation de la formation de biofilm chez Mh et que les prophages puissent intervenir dans la structure et/ou la dispersion du biofilm. Enfin, le rôle potentiel d’un îlot génomique dans la formation de biofilm sur trioléine a été suggéréHydrophobic organic compounds (HOCs), such as lipids and hydrocarbons, represent a significant part of the organic matter in the marine environment. Their low solubility in water requires from bacteria that degrade them physiological adaptations to stimulate their mass transfer from the organic to the aqueous phase where they are assimilated. Biofilm formation at the HOC-water interface is one of those adaptations. The marine bacterium Marinobacter hydrocarbonoclasticus (Mh) which is able to use a broad range of HOCs such as alkanes, fatty alcohols and triglycerides, was used as a model to study the biofilm formation at HOCs-water interfaces. The aim of my research was to (i) conduct the functional characterization of aupA and aupB genes which are overexpressed in biofilm on hexadecane, (ii) draw up a list of genes, through a transcriptomic study, that are potentially involved in adhesion and biofilm formation at HOCs-water interfaces in order to understand the molecular mechanisms involved.Functional study of aupA and aupB revealed that these two genes form an operon whose expression is activated by various types of HOCs. They have also been shown to be involved in the transport of hexadecane and in biofilm formation on alkanes. The AupA protein is localized in the outer membrane and the predicted lipoprotein AupB is located at the inner membrane. AupA belongs to a subfamily of the FadL-like transporters, specific to marine hydrocarbonoclastic bacteria (HCB). The phylogenetic distribution of the aupAB operon restricted to marine bacteria having the ability to degrade alkanes and its presence in multiple copies in somestrains of Alcanivorax sp. strongly suggest that Aup proteins play a key role in the adaptation of HCB to use alkanes as carbon and energy sources. The transcriptomic analysis of Mh cells adhering (after 15 min or 3 h of contact) or forming a biofilm at HOCs-water interfaces revealed significant and early changes in their transcriptome. The expression of many genes involved in the metabolism of HOCs, polysaccharides production, amino acids and ribosomal proteins synthesis is modulated as early as 15 min of adhesion. The overexpression of flagella and chemotaxis genes together with that of pili in adhesion condition suggest a possible motility at the interface during the early stages of biofilm development. In addition, it appears that the transcription factor RpoN is involved in the regulation of biofilm formation in Mh and that prophages could play a role in the structure and/or dispersal of the biofilm. Finally, a potential role of a genomic island in biofilm formation ontriolein was suggested
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Chepchirchir, Bilha [Verfasser], Gerrit [Akademischer Betreuer] Schüürmann, Gerrit [Gutachter] Schüürmann, and Ralf [Gutachter] Ebinghaus. "Occurrence and fate of endocrine disrupting chemicals and other hydrophobic organic compounds in a tropical river in Kenya / Bilha Chepchirchir ; Gutachter: Gerrit Schüürmann, Ralf Ebinghaus ; Betreuer: Gerrit Schüürmann." Freiberg : Technische Universität Bergakademie Freiberg, 2019. http://d-nb.info/1226101275/34.
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Šmídová, Klára. "Kinetika příjmu hydrofobních organických látek v žížale Eisenia andrei v půdách s rozdílným obsahem organického uhlíku." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240524.
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This thesis is concerned with the fate of hydrophobic organic pollutants (HOCs) in soil. The theoretical part summarizes the current knowledge about bioavailability, factors influencing the bioavailability and methods for its measurement. Attention is paid to the organic carbon content, which is considered to be one of the key factors and to the influence of microorganisms that can degrade or interact with the substances, thus changing their bioavailable ratio. The practical part of the thesis uses bioaccumulation test with earthworm Eisenia andrei for evaluating the uptake kinetics HOCs in three soils with different organic carbon content. Soils were laboratory contaminated with mixtures of selected HOCs (phenanthrene, pyrene, lindane, p,p'-DDT and PCB 153) and the concentrations of substances in these soils were followed for 217 days. Subsequently, bioaccumulation test was conducted; earthworms were exposed from one to twenty-one days. The collected data were used to model uptake kinetics curves for individual substances. Peak-shaped bioaccumulation were found for pyrene, for lindane a steady-state concentration during exposure was observed, whereas for p,p'-DDT and PCB 153 growing concentrations after twenty days of exposure were detected. The reason for the different behavior of the substances was probably their diverse sorption on the organic material, which together with the different speed of elimination influenced final concentration in earthworms. Phenanthrene was not detected in some samples and therefore the modeling of uptake kinetics was not possible.
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García, V. (Verónica). "Reclamation of VOCs, n-butanol and dichloromethane, from sodium chloride containing mixtures by pervaporation:towards efficient use of resources in the chemical industry." Doctoral thesis, University of Oulu, 2009. http://urn.fi/urn:isbn:9789514292644.
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Abstract
Volatile Organic Compounds (VOCs) in wastewaters from the chemical industry are of major concern because of their environmental and health impacts. The reclamation of VOCs from wastewaters would not only reduce the hazard to the environment but also contribute to an efficient use of resources. The thesis explores the reclamation of n-butanol and dichloromethane from sodium chloride containing mixtures by pervaporation. Another aim was to gain understanding of mass transport phenomena during the pervaporation of multicomponent systems, and the effect of sodium chloride on the pervaporation performance.
In this work, the reclamation of n-butanol and dichloromethane was conducted as a sequence of pervaporation stages which utilised first hydrophobic and then hydrophilic membranes. The objective was to segregate the mixture of n-butanol/dichloromethane/sodium chloride/water into three different streams: a re-use quality concentrate of VOCs, brine, and discharge quality purified water. The effect of the experimental variables, VOCs feed concentration, feed temperature and sodium chloride content on the performance of the pervaporation stages was studied. A statistical design, response surface methodology, was used to further resource efficiency.
The results indicate the potential of pervaporation for the reclamation of n-butanol and dichloromethane from aqueous mixtures. A single step of pervaporation of n-butanol/dichloromethane/sodium chloride/water systems using the CMX-GF-010-D (Celfa) and PERTHESE® 500-1 (P 500-1) membranes does not sufficiently concentrate the VOCs for direct re-use. It is also demonstrated that the electrolyte does not permeate through the membranes and does not affect their separation effectiveness significantly. The pervaporation of the water/dichloromethane/n-butanol system using the hydrophilic poly(vinyl alcohol)-titanium dioxide/polyacrylonitrile/polyphenylene sulfide (PVA-TiO2/PAN/PPS) membrane is effective for dewatering purposes. The membrane shows impermeable features towards dichloromethane in the studied conditions.
The analysis of the mass transport phenomena demonstrates that, under the experimental conditions studied, the resistance towards the mass transport of the compounds through the membrane is mainly exhibited by the membrane itself.
This study also shows the advantage of analysing the effect of temperature on membrane permeation by the permeation activation energy instead of by the apparent activation energy.
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Jordaan, Ilse. "Persistent organic pollutants (POPs) associated with a platinum mine in the Limpopo Province, South Africa / Ilse Jordaan." Thesis, North-West University, 2005. http://hdl.handle.net/10394/995.
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South Africa ratified the Stockholm Convention (SC), which became legally binding on 17
May 2004. This Convention targets 12 particularly toxic persistent organic pollutants (POPs)
for virtual elimination. The Convention also requires parties to reduce the release of
organochlorine pesticides and the intentionally- and unintentionally-produced POPs such as
dioxins, furans and polychlorinated biphenyls (PCBs) (referred to as dioxin-like chemicals).
Dioxins are a heterogeneous mixture of chlorinated dibenzo-p-dioxins and dibenzofurans
(PCDD/Fs) congeners. These substances were never intentionally produced but are produced
as by-products of industrial processes (such as metallurgical processes and bleaching of paper
pulp). They can also be formed during natural processes such as volcanic eruptions and forest
fires. The largest contributor to releases of PCDD/Fs in the environment is incomplete
combustion from waste incinerators leading to the unintentional production of these
compounds. Polychlorinated biphenyls (PCBs) are used in transformers and capacitors, but
can also be formed unintentionally during industrial and thermal processes. Dioxin-like
chemicals (PCDD/Fs and/or PCBs) are classified as persistent because of the following
characteristics: lipophilicity and hydrophobicity; resistance to photolytic, chemical and
biological degradation and they are able to travel long distances. As South Africa is a semiarid
region, POPs will be less prone to travel here because these substances favour colder
regions with high soil organic matter.
Fish, predatory birds, mammals (including humans) absorb high concentrations of POPs
through the process of bio-concentration, leading to bio-accumulation of these substances in
the fatty tissue. PCDD/Fs occur as unwanted trace contaminants in air, water, land, in
residues and products (such as consumer goods e.g. paper and textiles). The distribution of
these chemicals into various matrices is problematic since they cause damage to the
environment and human health. These chemicals pose a threat to human health when found
in high concentrations that may lead to acute hepatoxicity and dermal toxicity (chloracne).
Long-term exposure to low concentrations of these substances might lead to chronic effects
such as reproductive problems and carcinogenicity.
Since ferrous and non-ferrous metal production is a source of dioxin-like chemicals, a
platinum mine in the Limpopo Province, South Africa, was selected for this investigation.
The aim of the study was to determine if there are dioxin-like chemicals associated with
platinum mining and processing, and if the H4IIE reporter gene bio-assay could be used to
semi-quantify and assess the potencies of the complex environmental and process samples by
determining their Toxic Equivalency Quotients (TEQ). The implications of the sources to the
formation of dioxin-like chemicals regarding the SC were investigated and recommendations
were made to improve this study.
Samples were collected from tailings dams, woodchips, a dumpsite and slag from the smelter
at Union Section. Samples were extracted with the Soxhlet apparatus using hexane as
solvent. The percentage total organic carbon (%TOC) was determined for each sample to
normalise the data. The method used was the Walkley-Black method.
In determining the TEQ of each sample, the H4IIE luc cell line was used. The cells of the
H4IIE luc line are genetically modified rat hepatoma cells stably transfected with a luciferase
firefly gene. The luciferase gene is activated by the presence of dioxin-like compounds and
the concentration of the enzyme is measured as relative light units (RLUs). The amount of
RLUs is directly proportional to the dioxin load in the extract. This method is rapid, cost and
time-effective in determining the TEQ when compared to chemical analysis.
The TEQ2o-valuesin the various samples, as determined with the H4IIE luc cell line, ranged
from 0.007 ngTEQ/kg to 54.06 ngTEQ/kg. Thermal processes at the smelter, sorption of
hydrophobic organic compounds (HOCs) to soil and tailings, and external sources such as
anthropogenic activities contributed to high TEQ2o-values. Climatic conditions, wind,
precipitation, and solubility of HOCs into surfactants lead to low TEQ20. The smelter at
Union Section had a very high TEQ20of 44.62 ngTEQ/kg compared to Impala Platinum mine
(5.15 ngTEQ/kg). This implies that workers at Union Section are possibly exposed to low
and high concentrations of dioxin-like chemicals. Long-term exposure to these compounds
could lead to bio-accumulation in the fatty tissue of the mine workers, leading to chronic
effects such as reproductive problems and cancer. The air emission of the furnace at the
smelter was 0.03 gTEQ/annum and the release of the PCDD/Fs into the slag was 0.60
gTEQ/annum. By effectively managing the smelter it is possible to reduce the TEQ.
The TEQ of each sample increased due to normalising the data. The normalised TEQ20
ranged from 0.94 ng TEQ/kg to 42497.48 ngTEQ/kg.
Dioxin-like chemicals are present on a platinum mine, but at varying quantities and the effects
of these compounds might be detrimental to the environment and the workers at the platinum
mine. Further analyses of the health impacts associated with the platinum mine are needed.
The H4IIE reporter gene bio-assay could be used to effectively determine the TEQ of each
sample. Although this investigation has identified the formation and presence of dioxin-like
chemicals at certain stages of mining and processing, not all of the processes were
investigated. Some of these processes have the potential to add, and even destroy, these
chemicals, affecting potential human exposure and amounts released to the environment.
This, however, requires further investigation.
The financial assistance of the National Research Foundation (NRF) towards this
research is hereby acknowledged. Opinions expressed and conclusions arrived at, are
those of the author and are not necessarily to be attributed to the NRF.Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2006.
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Arantxa, Camus Etchecopar. "Mécanismes moléculaires impliqués dans la formation de biofilm à l’interface eau-composés organiques hydrophobes." Thesis, Pau, 2014. http://www.theses.fr/2014PAUU3032/document.
Full textAbstract:
Les composés organiques hydrophobes (HOC), une grande famille de molécules naturelles ou d’origine anthropique incluant les lipides et les hydrocarbures, constituent une part significative de la matière organique dans les écosystèmes marins. Du fait de leur faible solubilité dans l’eau, les bactéries qui les dégradent requièrent la mise en place de fonctions cellulaires spécifiques permettant d’augmenter la fraction assimilable de ces HOC. La formation de biofilms à l’interface eau-HOC est une de ces stratégies adaptatives. C’est le cas pour Marinobacter hydrocarbonoclasticus SP17, modèle d’étude utilisé au laboratoire, qui est capable de former des biofilms sur un large spectre de HOC métabolisables tels que les alcanes, les triglycérides et les alcools gras. Le but de mes recherches consistait à améliorer la compréhension du processus d’adhésion et de développement des biofilms sur les HOC, à travers la caractérisation fonctionnelle de 10 gènes candidats mis en évidence lors d’analyses d’expression en protéomique et en transcriptomique. Pour mener à bien ce projet, des outils génétiques et une caractérisation fonctionnelle propre à chaque gène ont dû être développés. L’étude fonctionnelle du gène MARHY2686 a relevé son implication dans la formation de biofilm sur les alcanes. La co-expression de MARHY2686 et des gènes adjacents MARHY2687 et MARHY2685 en transcriptomique, leur distribution phylogénétique et leur conservation de la synthénie suggèreraient que ces trois gènes soient impliqués dans le même processus biologique. D’après l’identité forte de 36 % qui existe entre la protéine MARHY2686 et une protéine périplasmique AdeT d’un système de pompe d’efflux tripartite d’Acinetobacter baumanii, cette protéine, en association avec MARHY2687 et MARHY2685, pourrait faire partie d’un système de ce type. Par ailleurs, des observations ont permis d’envisager une implication potentielle de ce gène dans l’assimilation des HOC ou dans l’accumulation des réserves lipidiques intracellulaires. M. hydrocarbonoclasticus SP17 utilise les pili de type IV lors de la formation de biofilm sur les HOC. Ces appendices interviennent lors de l’adhésion de cette souche à des HOC ainsi que dans un processus de détachement d’un support hydrophobe. Les pili pourraient soit intervenir directement pour permettre à la bactérie de se détacher de la surface à laquelle elle s’est adhérée, soit indirectement par l’action de bactériophages. La présence d’une mobilité de type twitching sur les HOC a pu être également envisagée. Enfin, le rôle du système de sécrétion de type VI (T6SS), connu pour permettre à la bactérie d’interagir avec une cellule hôte, lors de la formation de biofilm mono-spécifique sur HOC, où aucun autre microorganisme que M. hydrocarbonoclasticus SP17 n’est présent, a été étudiéHydrophobic organic compounds (HOC), a large family of naturally-produced or anthropogenic molecules including lipids and hydrocarbons, represent a significant part of organic matter in marine ecosystems. Because of their low solubility in water, bacteria that degrade those compounds require the establishment of specific cell functions to increase their biodisponibility. Biofilm formation in water-HOC interface is one of these adaptations. The model of bacteria used in our laboratory, Marinobacter hydrocarbonoclasticus SP17, is able to form a biofilm on a wide range of HOC, such as alkanes, fatty alcohols and triglycerides, in order to use them as a carbon and energy source. The main purpose of my work was to broaden the knowledge of how bacteria adhere to and from biofilms on HOC, through the functional characterization of 10 candidate genes highlighted during proteomic and transcriptomic studies. Genetic tools and a gene-specific functional characterization have been developed in order to carry out this project. Functional study conducted on MARHY2686 revealed its involvement in the formation of biofilm on alkanes. Co-expression of MARHY2686 and the adjacent genes MARHY2687 and MARHY2685 durnig transcriptomic analysis together with their phylogenetic distribution and synteny conservation suggest that these three genes are involved in the same biological process. According to the high peptide sequence identity between MARHY2686 and AdeT, a periplasmic protein of a tripartite efflux pump system of Acinetobacter baumanii, MARHY2686 in combination with MARHY2687 and MARHY2685 could be the components of such a system. Other phenotypic observations would consider the involvement of MARHY2686 either in the assimilation of HOC or in the accumulation of intracellular lipid reserves. M. hydrocarbonoclasticus SP17 uses type IV pili during biofilm formation on HOC. These appendages are involved in the adhesion of this strain to and in a detachment process from HOC. Type IV pili could either act directly to allow bacteria to detach from the surface to which it is adhered, or indirectly through the action of bacteriophages. The presence of twitching motility on HOC has also been suggested. Finally, the role of the type VI secretion system (T6SS), a well-known protein system which allows interactions between bacteria and host cells, during the formation of a mono-species biofilm on HOC where no other microorganism than M. hydrocarbonoclasticus SP17 is present, has been studied
22
Kuo, Dave Ta Fu 1978. "Thermodynamics and kinetics of hydrophobic organic compound sorption in natural sorbents and quantification of black carbon by electron microscopy." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/60793.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (v. 3, p.1198-1258).
The sorption behaviors of hydrophobic organic compounds (HOCs) in sediments were investigated using pyrene. Native pyrene desorbed slowly, taking from weeks to months to equilibrate. The end-point data suggested that, at nanogram-pyrene-per-liter porewater levels, sorption was much stronger than conventionally expected. The non-linearity of the isotherm may indicate physical occlusion of native sorbate and/or sorption onto micropore surfaces of char/charcoal. Between 30-70% of the native pyrene may be occluded. Conceptual pictures for both hypotheses were presented with supportive evidence from experiments and literature. Analysis of experimental and literature data suggested logKoc (organic-carbon normalized partition coefficient) and logKBC (black-carbon normalized partition coefficient) values were fairly constant across different geosorbents (around 4.5-5.7 and 5.6-6.3, respectively), while the non-linearity exponent varied substantially. This may explain the orders of magnitude scatter in logKoc's and logKBC's reported in recent reviews. An a priori non-linear numerical model based on Intra-particle Porewater Diffusion (IPD) was constructed and successfully predicted the desorption kinetics of native pyrene. Fitted kinetic parameters correlated with system and sorbate/sorbent properties. This suggested the empirical approach can be replaced by the a priori model and the diverse HOC desorption rates in the literature can be reconciled if relevant physicochemical properties are known. The regional fate of pyrene in Boston Harbor was evaluated with a box model using derived kinetic and equilibrium properties. Realistic predictions can be obtained when assuming pseudo steady state conditions, but not equilibrium partitioning, for the bed sediment and the water column. Furthermore, model results and literature evidence suggested that sediment resuspension may be a significant mobilization mechanism for sedimentary HOCs in estuaries and harbors. A new BC quantification method based on energy dispersive X-ray spectroscopy (EDX) was developed. The method identified/quantified Organic Carbon (OC) or Black Carbon (BC) by analyzing the elemental ratios of C, N, and 0 of the sample. Agreeable OC/BC estimates on a variety of carbonaceous materials were obtained using the method. The good analytical potential of the method warranted further exploration and methodological refinement. This study has great implications for the sequestration and bioavailability of HOCs in the environment.
by Dave T. F. Kuo.
Ph.D.
23
Quellec, Patricia. "Nanosphères "furtives" à base de copolymères biodégradables pour la libération contrôlée de principes actifs hydrophobes et de protéines." Vandoeuvre-les-Nancy, INPL, 1997. http://www.theses.fr/1997INPL133N.
Full textAbstract:
Des copolymères biodégradables amphiphiles constitués d'un bloc hydrophobe d'acide polylactique (PLA) et d'un bloc hydrophile de monométhoxypolyoxyéthylène (MPOE) ont été synthétisés dans le but de préparer des nanoparticules injectables furtives permettant une libération contrôlée dans le sang des principes actifs encapsulés. En tirant parti des propriétés amphiphiles des copolymères et en particulier des différences de solubilité des deux blocs en phase aqueuse et organique, les procédés d'émulsion/évaporation (simple émulsion, huile-dans l'eau) et de double émulsion huile-dans l'eau-dans l'huile adoptés conduisent à la formation de nanosphères constituées d'un cœur dense hydrophobe de PLA, recouvertes d'une brosse hydrophile de MPOE. Cette dernière a pour but d'empêcher l'adsorption des protéines (opsonisation), phénomène qui déclenche la réponse immunitaire, et protéger ainsi les nanoparticules de l'élimination de la circulation sanguine. Les propriétés de surface des nanosphères ont été étudiées, notamment du point de vue de la charge, et comparées à celles de nanosphères de PLA non recouvertes de MPOE. Suivant les procédés de simple ou double émulsion appliqués, il a été possible d'encapsuler efficacement un principe actif hydrophobe (Cyclosporine A, médicament aux propriétés immunosuppressives) et une protéine modèle (albumine du sérum humain). Les taux d'encapsulation et charges en principes actifs ont été étudiés en fonction de divers paramètres (concentration en polymère, charge théorique en principe actif, taux de MPOE dans la matrice) et les cinétiques de libération ont été suivies in vitro. Ainsi, nous avons montré qu'il était possible de retarder la libération des principes actifs lorsqu'ils sont incorporés dans une matrice biodégradable. Enfin, nous avons mis en évidence l'efficacité de la brosse protectrice de MPOE en surface des nanosphères vis-à-vis de l'adsorption des protéines plasmatiques et de la capture par des cellules phagocytes humaines (polymorphonucéaires).
24
Brehm, Marius [Verfasser], and P. [Akademischer Betreuer] Levkin. "Miniaturized and Parallel Synthesis of Compound Libraries for High-Throughput On-Chip Screening on Hydrophilic-Hydrophobic Patterned Surfaces / Marius Brehm ; Betreuer: P. Levkin." Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/123507241X/34.
Full text
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RIFI, EL HOUSSEINE. "Extraction metallique par des gels hydrophobes." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13158.
Full textAbstract:
Etude de l'extraction liquide-gel de cu, v et eu. On montre que les lois de la thermodynamique d'extraction de cu par les acyl-4 pyrazolones-5 ne sont pas pertubees par la presence du polymere, mais que la cinetique l'est fortement. L'impregnation des polybutadienes par la trilamylamine presente des difficultes; l'utilisation de pvc gonfle dans des solutions d'oxyde d'octylphenyl n,n-diisobutylcarbamoylmethylphosphine dans tbp est interessante
26
Schott, Marc-Alexandre. "Encapsulation moléculaire de molécules actives hydrophobes par des polymères amphiphiles aléatoires à base de poly(acide diméthylmalique)." Thesis, Montpellier 1, 2012. http://www.theses.fr/2012MON13510/document.
Full textAbstract:
Nombre de principes actifs rencontrent des problèmes liés à leur faible hydrosolubilité : mauvaise biodisponibilité, métabolisation désactivante, effets secondaires. Pour contourner ce problème, des polyélectrolytes amphiphiles aléatoires ont déjà été étudiés. S'ils ont amélioré la solubilité apparente de composés hydrophobes, ils étaient parallèlement toxiques ou non dégradables, donc non éliminables par l'organisme. Dans ce mémoire, nous présentons la synthèse de différentes malolactones substituées. La copolymérisation anionique par ouverture de cycle de ces lactones a permis d'obtenir une famille de polyanions amphiphiles aléatoires avec un taux d'hydrophobisation variable et contrôlé, et des chaînes latérales, aliphatiques ou aromatique, de différentes longueurs. Ces polymères augmentent la solubilité aqueuse apparente de composés hydrophobes. Lorsque le composé est cationique, une synergie entre interactions hydrophobes et électrostatiques a été mise en évidence. La solubilité apparente de molécules anti-infectieuses a ainsi pu être améliorée de plusieurs ordres de grandeur. Dans les conditions d'une administration intraveineuse (NaCl 9 g.L-1 et pH = 7,5), ces polymères forment préférentiellement des micelles intramoléculaires qui ne sont pas sensibles aux effets de dilution. Un tel système de transport de principes actifs ne produirait donc aucune libération prématurée. Ces polymères étant de plus dégradables, ils pourraient libérer le principe actif et seraient éliminables par l'organisme. Les polymères présentés dans ce manuscrit remplissent les principaux critères physico-chimiques pour former un système de transport de molécules activesLots of drugs meet some problems because of their poor water-solubility : poor bioavailability, desactivating metabolization, side effects. To overcome these problems, some amphiphilic polyelectrolytes have already been studied. They increased the apparent water-solubility of hydrophobic compounds, but were toxic or not degradable, thus could not be eliminated from the body. In this work, we describe the synthesis of various substituted malolactones. Anionic ring opening copolymerization of these lactones yielded random amphiphilic polyanions with varying and controlled hydrophobization ratio and aliphatic and aromatic side chains with different lengths. These polymers increase the apparent water-solubility of hydrophobic compounds. A synergy between hydrophobic and electrostatic interactions has been demonstrated when the compound is cationic. The apparent solubility of anti-infectious drugs could thus be increased by several orders of magnitude. Under intravenous injection conditions (NaCl 9 g.L-1 and pH = 7,5), these polymers form preferentially intramolecular micelles, which are not sensitive to dilution effects. As a consequence, such a drug transport system would yield no premature release. Being also degradable, these polymers could release the drug and be eliminated from the body. They meet all main physico-chemical criteria to become a drug transport system
27
Bitteur, Sylvaine. "Etude, par chromatographie en phase liquide, du partage de composes d'arôme entre une phase aqueuse et des phases stationnaires hydrophobes." Paris 6, 1986. http://www.theses.fr/1986PA066449.
Full textAbstract:
Ce travail a consisté à étudier dans quelle mesure la chromatographie en phase liquide permet d'extraire les composes d'arôme présents en très faible concentration dans les effluents aqueux des industries agro-alimentaires. Les rendements d'extraction accessibles par enrichissement de traces étant directement lies aux facteurs de capacité des solutés d'intérêt, l'étude proposée se ramenait à celle du partage de composes d'arôme entre une phase aqueuse et des phases stationnaires hydrophobes. La première partie détaille les divers paramètres susceptibles de modifier les rendements d'extraction par les principaux types de supports apolaires de la chromatographie en phase liquide et met en évidence le caractère indispensable d'une étude systématique préalable. Une telle étude, menée à l'aide de composes modèles d'arôme et de supports chromatographiques choisis fait l'objet de la seconde partie. L'ensemble des résultats obtenus au terme de cette études systématique est finalement teste dans le cas concret d'un effluent aqueux industriel contenant des composes d'arôme de cassis à l'état de traces.
28
Caniparoli, Jean-Philippe. "Etude par resonance magnetique nucleaire des conformations et des interactions moleculaires dans les mesophases lyotropes : application a des problemes de solubilisation." Paris 6, 1988. http://www.theses.fr/1988PA066117.
Full textAbstract:
Etude par rmn, de l'ordre et de la dynamique moleculaire des phases lyotropes de systemes binaires agent de surface a double chaine/eau: parametres d'ordre eleves, probabilites conformationelles, temps de correlation des mouvements moleculaires tres anisotropes en fonction de la tete polaire (phosphate ou ammonium); faible influence de la longueur de la chaine. Etude de l'ordre et de la dynamique de petites molecules en solution dans le systeme dibutylphosphate de sodium/eau en phase lamellaire: influence importante du caractere hydrophile ou hydrophobe du solute. Localisation des solutes non complexants dans le cristal liquide d'apres la relaxation induite par un ion paramagnetique
29
Ma, Zhiyuan. "Glycopolymers containing hydrophobic natural compounds." Thèse, 2018. http://hdl.handle.net/1866/22632.
Full text
30
Tsai, Chia-Line, and 蔡佳霖. "Effusion of Hydrophobic Organic Compounds(HOCs) from Fog." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/65090253690322721262.
Full text
31
Lo, Jin-Hsiang Andy, and 羅金翔. "Dissolution of Hydrophobic Organic compounds in Fog Droplets." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/67260924775299094885.
Full textAbstract:
博士國立臺灣大學
環境工程研究所
84
In this study, effusion process and solubilization process were conducted to investigate the enriched solubility of n-octane, a surrogate of the hydrophobic organic compounds in atmospheric fog. In effusion process, we presented a dynamically corrected double-layer diffusion model with a new parameter, the effusion factor (.alpha.) to quantify the change of the effusion rate across the air/fog interface. The .alpha. values were in the range of 0.798 to 0.421 for the effect of SDS. Thus, SDS could decrease the mass transfer of n-octane effusing from the fog droplet by about 20 to 60%. However, the .alpha. values varied from 1.17 to 1.57 and 1.42 to 4.23 for the effects of sulfuric acid and NaCl, respectively. Therefore, the ionic strength contributed by sulfuric acid and NaCl could enhance the effusion rate of n-octane by about 17 to 57% for the effect of sulfuric acid and 42 to 323% for the effect of NaCl. NaCl resulted in stronger effusion rate of n-octane from the fog droplets than sulfuric did because of the stronger ionic hydration provided by NaCl. As for solubilization process, the surfactant film on the fog droplets was identified to elevate the solubility of n-octane. The enrichment factor (EF) of n- octane in the fog droplets (diameter: 35 to 75 .mu.m) were between 27.2 to 1.87, depending on the SDS concentration (0.00285M to 0.0000515M). In addition, the larger fog droplets provided n-octane with higher EF value than the smaller fog droplets while below the specific SDS concentration, 0.000103M, The enrichment model was used to describe the micro-states of the n-octane molecules partitioning in the SDS film at the air/ fog interface and the SDS monomers inside the fog water. Above enriching effect could be easily expounded and discussed by use of this model.
32
Jiang, Zhengzheng. "Influence of nonlinear sorption on groundwater transport of hydrophobic organic compounds." 2006. http://proquest.umi.com/pqdweb?did=1075714081&sid=22&Fmt=2&clientId=39334&RQT=309&VName=PQD.
Full textAbstract:
Thesis (M.S.)--State University of New York at Buffalo, 2006.Title from PDF title page (viewed on July. 21, 2006) Available through UMI ProQuest Digital Dissertations. Thesis adviser: Rabideau, Alan J. Includes bibliographical references.
33
Li, Fang-Yu, and 李芳瑜. "Metal-Organic Framework Composites for the Extraction of Hydrophobic and Hydrophilic Compounds." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/qkepjd.
Full textAbstract:
碩士中原大學
化學研究所
106
In this study, the applications of polystyrene and metal-organic frameworks (MOFs@PS) composite materials in solid phase microextraction (SPME) are discussed. Several parameters affecting the extraction efficiency of different MOFs@PS in SPME application were also investigated. First, different MOFs@PS composites were synthesized via post modification of PS core using sulfuric acid (H2SO4) and subsequently grown the MOF nanomaterials. Herein, a terephthalic acid based aluminum MOF, MIL-53(Al), was synthesized onto the PS core (MIL-53(Al)@PS) and applied in the extraction of hydrophilic analytes NSAIDs. To make a useful comparison, the extraction efficiency of polystyrene (PS), and pristine MIL-53(Al) were also investigated. The results showed that the extraction recoveries for NSAIDs using MIL-53(Al)@PS composite was found higher compared to its counterpart. Due to the structure of PS, which contains one aromatic ring, the adsorption behavior of the NSAIDs via π-π interaction was found weaker. Meanwhile, the presence of MIL-53(Al), which exhibits high porosity, large surface area, further enhanced the extraction efficiency for NSAIDs. On the other hand, another MOF, aluminum 1,4-naphthalenedicarboxylic acid (Al-1,4-NDC), was grown onto the PS core (Al-1,4-NDC@PS) and applied in SPME of NSAIDs. The results showed that the extraction recoveries for NSAIDs using Al-1,4-NDC and Al-1,4-NDC@PS were in the range of 78.8 %-82.5 % and 93.0 %-98.9 %, respectively. Comparing this result suggests that Al-1,4-NDC@PS, which contains bicyclic benzene rings, exhibited better extraction performance than to that of the MIL-53(Al)@PS due to its high π-π interaction sites. The enhanced efficiency of Al-1,4-NDC@PS composite also showed the ease of elution for NSAID analytes with high recoveries. Second, further investigation on the potential of Al-1,4-NDC@PS composites in SPME of hydrophobic polyaromatic hydrocarbons (PAHs) was conducted. The results showed that the extraction recoveries for PAHs using PS, Al-1,4-NDC and Al-1,4-NDC@PS composites were in the range of 37.7 %-59.0 %, 60.8 %-82.9 % and 60.0%-96.4%, respectively. These results also proved that the Al-1,4-NDC@PS composite could be useful in the extraction of hydrophobic analytes. Finally, the successful preparation of MOFs@PS composites demonstrated their potential as adsorbent for both hydrophilic and hydrophobic analytes.
34
Liu, Yi-Ying, and 劉奕瑩. "Mass Transfer of Hydrophobic Volatile Organic Compounds In a Rotating Packed Bed." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/69565730967159310279.
Full textAbstract:
碩士國立臺灣大學
化學工程學研究所
96
In this study, absorption process that applies on treating hydrophobic volatile organic compounds (VOCs) in a cross-flow rotating packed bed (RPB) was investigated. In the literature of the past, it was usually used water to treated hydrophilic VOC on absorption process, because water was an inexpensive, available and effective absorber. When treating VOC, water is not more appropriate absorber. Most of hydrophobic absorbers have high viscosities to influence the operation in packed column and cause flooding. In RPB, it replaces gravity with centrifugal force, so it can be operated on a more extensive range of gas and liquid flow rate, and it does not restrict by high viscosity and choice more different absorber. In this study, we pondered over the Henry’s constant, viscosity, cost and safety of absorbers, and finally chose silicon oil to treated hydrophobic VOCs (toluene, xylene) on the absorption process. According to the experimental results, mass transfer efficiency increased with rotational speed, gas and liquid flow rate. However, the concentration of gas inlet had little influence on mass transfer efficiency. Mass transfer coefficient maintained a constant value on the range of those concentrations. At low rotational speed (800 RPM) and low liquid flow rate (240 mL/min), according to the experimental results and visual observation, there were no well liquid distribution in RPB; it made mass transfer efficiency decrease. Toluene and xylene were absorbed by silicon oil with high liquid flow rates and high rotational speeds; its efficiency exceeded 95% and achieved the standard of direct emission, so this was a safe and efficient chemical engineering process on treating hydrophobic VOCs. Finally, all experimental data were correlated into an empirical formula, and it estimates mass transfer coefficient on an extensive range of liquid viscosity in a cross-flow RPB.
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Martins, Afonso Cerqueira. "Ionic liquids as hydrotropes: the key towards solubility increase." Master's thesis, 2021. http://hdl.handle.net/10773/31141.
Full textAbstract:
Water solubility of hydrophobic compounds is a crucial factor
in the formulation of drugs, cleaning products and personal hygiene.
Therefore, technology that allows us to increase their solubility and
dissolution rate has attracted considerable interest not only at an
academic level but also at an industrial one. In this sense,
hydrotropes have been under the spotlight. These compounds are
characterized as molecules possessing the capacity of promoting a
drastic, several-fold increase in aqueous solubility of highly
hydrophobic compounds. Recently, ionic liquids have been
appointed as a promising class of catanionic hydrotropes, since both
the cation and anion can contribute to the solubility increase.
Although there is a vast amount of reviewing work centred on
hydrotropy, its underlying mechanism is not yet fully understood.
This work proposes to study the impact of salt addition on the
hydrotropy phenomenon as to better understand its mechanism,
both experimentally and through simulation. Herein the addition of
chloride salts to aqueous solutions of an ionic liquid was found to
hinder solubility by promoting aggregation of the latter, with a notably
nuanced behaviour according to the salt cation valence.
Hydrophobic interactions were found to be central to the aggregative
effect of the hydrotrope around the solute, which seem to drive
hydrotropy. The interactions between the hydrotrope and the solute
presented a degree of site-specificity, lost with salt addition.
Hydrotrope aggregation showed to be detrimental to the hydrotropic
effect, disproving one of the dominant theories justifying the
mechanism of hydrotropy.A solubilidade em água de compostos hidrofóbicos é um fator crucial na formulação de fármacos, produtos de limpeza e de higiene pessoal. Assim, a tecnologia que permite aumentar a solubilidade e a taxa de dissolução dos mesmos tem atraído um considerável interesse não só a nível académico como industrial. Neste sentido, os hidrótropos têm sido alvo de muita atenção. Estes compostos são caracterizados como moléculas com capacidade de promover um drástico aumento da solubilidade aquosa de compostos fortemente hidrofóbicos, aumento este em várias ordens de magnitude. Recentemente, os líquidos iónicos foram apontados como uma classe promissora de hidrótropos cataniónicos, uma vez que quer o catião como o anião pode contribuir para o aumento da solubilidade. Embora haja um vasto número de trabalho de revisão com foco na hidrotropia, o mecanismo de ação por detrás deste fenómeno ainda não está claramente entendido. Este trabalho pretende averiguar o impacto da adição de um sal no fenómeno de hidrotropia com o intuito de melhor compreender o seu mecanismo, experimentalmente e através de simulação. A adição de cloretos a soluções aquosas de um líquido iónico demonstrou prejudicar a solubilidade ao promover a agregação do hidrótropo, com um comportamento com várias nuances, mas limitadamente sob uma ordenação de acordo com a valência do catião do sal adicionado. Interações hidrofóbicas mostraram-se centrais no efeito de agregação do hidrótropo em volta do soluto, que parece conduzir a hidrotropia. As interações entre o hidrótropo e o soluto apresentam um grau de especificidade de local, perdido com a adição de sal. A agregação do hidrótropo mostrou-se prejudicial para o efeito hidrotrópico, refutando uma das principais teorias justificativas do mecanismo da hidrotropia.
Mestrado em Bioquímica
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Huang, Wei-Chieh, and 黃偉杰. "Target identification of small-molecule compounds by affinity elution in tandem hydrophobic interaction chromatography (AETHIC)." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/65389622126866640167.
Full textAbstract:
博士國立臺灣大學
生化科學研究所
104
Target identification is essential to understanding the complicated actions of bioactive small compounds. However, available techniques constrained by processing time and specific equipment do not meet the growing demands. Here, we have developed a novel method combining hydrophobic interaction chromatography and affinity elution, named affinity elution in tandem hydrophobic interaction chromatography (AETHIC) that enables systematic and efficient identification of small molecule-protein interactions. The essence of this strategy is using a series of HIC matrices encompassing aliphatic chains of different length which provide a wide range of hydrophobicity for interactions with most proteins. After samples are applied to the tandem columns, target proteins are selectively eluted with a specific ligand. As our first proof-of-principle of AETHIC, we demonstrated that AETHIC was able to enrich ATP-binding proteins from mouse brain extract as near nineteen percent of total protein identifications are previously assigned ATP binders. In addition, we have revealed that raf kinase inhibitory protein (RKIP) is an ATP binding protein. ATP attenuates the interaction between RKIP and Raf-1. As a result, short-term energy depletion augments interaction between RKIP and Raf-1 resulting in decreased activation of the downstream ERK signaling in cultured HEK293 cells. Therefore, the ATP-binding function renders RKIP’s inhibition on Raf-1 modulated by cellular ATP concentrations. These data shed light on how energy levels link to cellular signaling. In light of these results, we envisaged the potential of AETHIC to be applied in the target identification of bioactive compounds such as metabolites and therapeutic small-molecule drugs.
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Qian, Yuan [Verfasser]. "Sorption of hydrophobic organic compounds (HOCs) to inorganic surfaces in aqueous solutions / vorgelegt von Yuan Qian." 2010. http://d-nb.info/1013135342/34.
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Wu, Chih Cheng, and 吳致呈. "Effect of Non-ionic Surface Active Substance on the Effusion of Hydrophobic Organic Compounds from Droplets." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/66435449423845464989.
Full textAbstract:
碩士國立臺灣大學
環境工程學研究所
86
ABSTRACT Non-ionic surfactants , Tween 20 , Tween 60 and Tween 80 were used to investigate the effect of non-ionic surface active substance on the effusion of hydrophobic organic compounds from fog droplet . N-decane was chosen as a surrogate of hydrophobic organic compounds (HOCs) . N-decane in aqueous samples was by SPME(solid phase microextration) and relative standard deviation of analysis (RSD%) are between 2.2%~7.5% . The collection bottle was ice bathed to prevent the vaporization of n-decane . Double layer d The results show that Tween 20 , Tween 60 and Tween 80 can decrease the mass transfer of n-decane from 107.8μm droplet to gas phase . At Tween 20 concentration 1.0~12.0×10-2g/L , theα values are decreased 11.9~55.2% . At Tween 60 concentration 1.0~9.7×10-2g/L , the reduction percentage of α values are between 1.8~58.1% . At Tween 80 concentration 5×10-3~12.0×10-2 g/L , the reduction percentage of α values are between 6.2~65.3% . The effect of non-ionic surfactants on effusion can categorized into two Below the concentration of 1.0×10-3M NaCl , salt effect can be ignored whether Tween 20 concentration is below the cmc or above . But , at high concentration of NaCl(1.0×10-2M) , salt effect reduce n-decane effusion (α reduction by 43.4%) when Tween 20 concentration is below the cmc and enhance the effusion (α increase by 48.6%) when Tween 20 concentration is above cmc . Low pH can enhance n-decane effusion whether Tween 20 concentration is below the cmc or not .
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Tedyono, Rico, and 鄭文生. "Extraction of phenolic compounds from aqueous solution using a slightly hydrophobic nonionic surfactant Tergitol 15-S-5." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/52348804021514755081.
Full textAbstract:
碩士國立成功大學
化學工程學系碩博士班
97
A simple and rapid L3-phase extraction technique was developed to recover mixtures of phenolic compounds, including 8 priority phenolic pollutants, from aqueous solutions using nonionic surfactant Tergitol 15-S-5 at ambient temperature. The readily biodegradable Tergitol 15-S-5 surfactant is a mixture of species with secondary ethoxylated alcohols, and exhibits as a dispersion of the lamellar phase in water (Lα + W) at ambient temperature (24ºC). Hence, salting-out electrolytes were in need to induce the phase separation along the boundary of L3 + W phases at ambient temperature. Effects of different electrolytes, such as monovalent LiCl, NaCl and KCl, as well as bivalent MgCl2 and CaCl2, to the L3-based extraction process were studied. The strategy to achieve a high preconcentration factor was successfully demonstrated with increasing concentration of salting-out additives and/or decreasing the surfactant concentration, which could be attributable to increase the volume of water phase. The optimum conditions for the extraction and preconcentration of these selected phenolic compounds have been established as follows, 0.2% wt of Tergitol 15-S-5 + 5.6% wt of NaCl. Moreover, the logarithms of distribution coefficients of these phenolic compounds between coexisting L3 phase and water phase was found to be linearly proportional to the logarithms of n-octanol/water distribution coefficients of these phenolic compounds.
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Chepchirchir, Bilha. "Occurrence and fate of endocrine disrupting chemicals and other hydrophobic organic compounds in a tropical river in Kenya." 2017. https://tubaf.qucosa.de/id/qucosa%3A32680.
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This thesis explores the application of passive sampling as a novel monitoring technique capable of quantifying aquatic pollutants at low environmental concentrations, and in a form that is directly applicable to risk assessment. Two passive samplers, namely polyethersulfone (PES) and silicone rubber (SR), were used to monitor some endocrine disruptors (EDCs) and hydrophobic organic chemicals (HOCs) in freshwater and sediments of a tropical river in Kenya. PES was applied for the first time for time-integrative sampling of these compound classes and was able to quantify the target compounds at low concentrations that were not significantly different to those obtained using the well-established SR, despite differences in uptake mechanisms with both sampler materials. This study demonstrated that passive samplers are versatile tools that can be applied in remote locations, and with proper storage, they can be transported and analyzed far afield.
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Dalton, Sarah Kathryn. "Transport and lipid solubility of hydrophobic organic compounds using semipermeable membranes: Influence of dissolved organic matter and solution chemistry." Thesis, 2002. http://hdl.handle.net/1911/17497.
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Association of hydrophobic organic compounds with dissolved organic matter in natural water systems may impact a contaminant's ability to transport across synthetic membranes. Importantly, these interactions can create interferences when monitoring ambient levels of contaminants with a potential for biouptake. The influence of water-quality matrix conditions on the transport and lipid uptake of five hydrophobic organic compounds of environmental concern was investigated by partnering semipermeable membranes with a model lipid phase in a batch dialysis system. Contaminants fell into two characteristic groups based on the response of transport and lipid uptake to exposure conditions: one for which behavior was largely independent of water-quality matrix conditions and one for which alterations to the bulk aqueous phase were impactful. For short exposure periods, the abiotic technique demonstrated the potential to qualitatively replicate the root-to-shoot translocation behavior of non-ionized hydrophobic organic compounds in plant systems.
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Moyo, Francis, R. Tandlich, Brendan S. Wilhelmi, and Stefan Balaz. "Sorption of hydrophobic organic compounds on natural sorbents and organoclays from aqueous and non-aqueous solutions: a mini-review." 2014. http://hdl.handle.net/10962/71614.
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Renewed focus on the sorption of hydrophobic organic chemicals (HOCs) onto mineral surfaces and soil components is required due to the increased and wider range of organic pollutants being released into the environment. This mini-review examines the possibility of the contribution and mechanism of HOC sorption onto clay mineral sorbents such as kaolinite, and soil organic matter and the possible role of both in the prevention of environmental contamination by HOCs. Literature data indicates that certain siloxane surfaces can be hydrophobic. Therefore soils can retain HOCs even at low soil organic levels and the extent will depend on the structure of the pollutant and the type and concentration of clay minerals in the sorbent. Clay minerals are wettable by nonpolar solvents and so sorption of HOCs onto them from aqueous and non-aqueous solutions is possible. This is important for two reasons: firstly, the movement and remediation of soil environments will be a function of the concentration and type of clay minerals in the soil. Secondly, low-cost sorbents such as kaolinite and expandable clays can be added to soils or contaminated environments as temporary retention barriers for HOCs. Inorganic cations sorbed onto the kaolinite have a strong influence on the rate and extent of sorption of hydrophobic organic pollutants onto kaolinite. Structural sorbate classes that can be retained by the kaolinite matrix are limited by hydrogen bonding between hydroxyl groups of the octahedral alumosilicate sheet and the tetrahedral sheet with silicon. Soil organic carbon plays a key role in the sorption of HOCs onto soils, but the extent will be strongly affected by the structure of the organic soil matter and the presence of soot. Structural characterisation of soil organic matter in a particular soil should be conducted during a particular contamination event. Contamination by mining extractants and antibiotics will require renewed focus on the use of the QSAR approaches in the context of the sorption of HOCs onto clay minerals from aqueous and non-aqueous solutions.
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Lin, Bing-Yi, and 林秉毅. "Liquid-phase Photocatalytic Degradation of hydrophobic Organic Compound Collaborate with Surfactant." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/67483006918240263109.
Full textAbstract:
碩士國立高雄第一科技大學
環境與安全衛生工程所
91
The purpose of this research is to study the effect of surfactants on liquid-phase photocatalysis of perchloroethylene (PCE) by using TiO2 as a photocatalyst. Series of photocatalytic experiments are conducted in a batch photocatalytic reactor in which 2000 mg/L anatase TiO2 powder is suspended and four near-UV light lamps are surrounded as the light source. Several experimental parameters including different types of surfactants (SDBS, TX100 and CPC), the concentrations of surfactants, solution pH levels ranging from 3 to 11, and light illumination time are investigated to discuss their influence on PCE degradation. The experimental results indicate that the photocatalytic degradation of PCE basically follows a first order reaction but it is usually inhibited in the presence of surfactants. The inhibited reaction rates may be due to the adsorption-competition for activated sites on photocatalysts. For the inhibition on PCE decomposition by different types of surfactants, the tendency for the inhibition is in the order of SDBS > TX100 > CPC. That is, the decomposition rates of PCE are more easily inhibited by anionic surfactants and those may be enhanced in the presence of proper amount cationic surfactants. There are two reaction patterns for the change in the degradation rates of PCE resulting from different concentrations of surfactants. As surfactant concentrations are below its CMC, the obviously inhibited decomposition of PCE is observed and the reaction rates are decreased quickly as surfactant concentrations are increased. On the other hand, although the habited decomposition of PCE is also observed as the concentrations of surfactant higher than its CMC, the retarded reaction rates for PCE photocatalysis approach to constant values for both PCE-SDBS and PCE-TX100 reaction systems, but the rates are continually decreased for the PCE-CPC system. In addition, pH has an important effect on degradation of PCE. Not only surfactants can be decomposed under the acid environment and may cause the breakage in their molecular structures, but also surfactants may become more active to as short molecules, which are more easily adsorbed by TiO2 and result in the deterioration in the PCE degradation rates. Thus, more complex reactions for PCE photocatalysis accompanied with different types of surfactants under various solution pH levels would be expected. More inspections would be required for future investigations.
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Huang, Wei shiang, and 黃韋翔. "The Investigation of Hydrophobic Organic Compound Sorption on Humic Substances with Size Fraction Molecular Weight." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/24002757303547171570.
Full textAbstract:
碩士國立屏東科技大學
環境工程與科學系所
101
A recent, rapid population growth has caused additional domestic sewage, industrial and livestock wastewater, and pollutants to discharge into the environment. Estrogenic phenol compounds such as nonylphenol (NP), octylphenol (OP), bisphenol A (BPA), and polycyclic aromatic compounds such as phenanthrene and pyrene are hydrophobic and easily sorbed and partitioned on humic substances (HS) in sediment, which increases the impact on an aquatic environmental ecosystem. In this study, both water and sodium hydroxide (NaOH) solvents were used to extract HS from air- and freeze-dried sediments sampled from WuLo Creek. The extracted HS was size-fractioned, with physical methods, into high molecular weight HS (10 kDa &;lt; HMWHS &;lt; 0.45 μm), middle molecular weight HS (1 kDa &;lt; MMWHS &;lt; 10 kDa), and low molecular weight HS (MMWHS &;lt; 1 kDa). The HS properties were examined with UV/Vis and fluorescence indices that analyzed UV/Vis absorbance and produced an excitation/emission matrix. Furthermore, a fluorescence quenching method was used to obtain the partition coefficients (KDOM) between the sediment HS and estrogenic compounds. The optical properties indices were used to evaluate the factors that may affect the KDOM. The results showed that the HMWHS and MMWHS absorbed the estrogenic compounds better than the LMWHS because the HMWHS and MMWHS had a higher degree of humification than the LMWHS. In addition, HS extracted with NaOH demonstrated a much higher sorption capacity of the organic pollutants than those extracted with water. The log KDOM values ranged from 4.28 to 5.44 for NP, from 4.24 to 4.83 for OP, from 4.60 to 5.03 for BPA, from 3.97 to 4.44 for phenanthrene, and from 34.9 to 4.35 for pyrene. The HS extracted with NaOH contained much more dissolved organic matter than HS extracted with water. The HS extracted from air-dried sediment had a better sorption capacity than HS extracted from freeze-dried sediment because the microorganisms were not active after sediment was freeze-dried. Its original composition contained a high ratio of protein-like substances. The microorganisms continued to decompose and oxide the HS in the air-dried sediment, which changed the properties of organic matter. Fluorescence peaks of HMWHS and MMWHS were centered at a longer wavelength than LMWHS. This is called a red shift with a high degree humification of HMWHS and MMWHS. The fluorescent index (FIX) had a significant correlation with the partition coefficients (p &;lt;0.01).
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Spolar, Ruth Margaret. "The role of the hydrophobic effect in site-specific protein-DNA interactions and protein folding a thermodynamic analysis using model compound transfer data /." 1991. http://catalog.hathitrust.org/api/volumes/oclc/24528144.html.
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Thesis (Ph. D.)--University of Wisconsin--Madison, 1991.Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Lee, Myung Jae. "Adsorption of Alkaline Copper Quat Components in Wood-mechanisms and Influencing Factors." Thesis, 2011. http://hdl.handle.net/1807/29788.
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Mechanisms of adsorption of alkaline copper quat (ACQ) components in wood were investigated with emphasis on: copper chemisorption, copper physisorption, and quat adsorption. Various factors were investigated that could affect the adsorption of individual ACQ components in red pine wood. Copper chemisorption in wood was affected by ligand types coordinating with Cu and the stability of the Cu-ligand complexes in solution. For Cu-monoethanolamine (Cu-Mea) system, the prevailing active solvent species at the solution pH, [Cu(Mea)2-H]+ complexes with wood acid sites and loses one Mea molecule through a ligand exchange reaction. The amount of adsorbed Cu was closely related to the cation exchange capacity of wood. An increase in Mea/Cu ratio increased the proportion of the uncharged Cu-Mea complex and resulted in decreased Cu chemisorption in wood. Copper precipitation is also an important Cu fixation mechanisms of Cu-amine treated wood. X-ray diffraction analysis revealed that in vitro precipitated Cu was a mixture of copper carbonates (azurite and malachite) and possibly Cu2O. Higher concentration Cu-amine solutions retarded the Cu precipitation to a lower pH because of higher free amine in the preservative-wood system. The changes in zeta potential of wood in relationship to the quaternary ammonium (alkyldimethylbenzylammonium chloride: ADBAC) adsorption isotherm showed two different adsorption mechanisms for quat in wood: ion exchange reaction at low concentration and additional aggregation form of adsorption by hydrophobic interaction at high concentration. Because of the aggregation effect, when wood was treated with ACQ, high amounts of ADBAC were concentrated near the surface creating a steep gradient with depth. This aggregated ADBAC was easily leached out while the ion exchanged ADBAC had high leaching resistance. Free Mea and Cu of ACQ components appeared to compete with ADBAC for the same bonding sites in wood.