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1
Tuncel, van Pomeren Binnur. "Molecular complexes of 4,4'-dinitrobiphenyl." Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-03132006-155913.
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Goswami, Debarghya. "Studies on some biphenyl benzoate based chiral liquid crystal compounds." Thesis, University of North Bengal, 2020. http://ir.nbu.ac.in/handle/123456789/4038.
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MacKinnon, Angus. "Diffraction and database analyses of photoactive biphenyl compounds and novel carbaborane structures." Thesis, Durham University, 1999. http://etheses.dur.ac.uk/4594/.
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The research involved in this thesis is mainly concerned with crystallography and the analysis using crystallographic techniques and methods. The work in this thesis is centered mainly on two types of chemical compounds, photoactive compounds and carbaboranes. The first is the photoactive compounds of biphenyl, its derivatives and similar compounds; these compounds have been studied by diffraction and database analysis. The photochemistry and subsequent structural analysis of biphenyls has been studied in collaboration with Professor Peter Wan at the University of Victoria, Canada. In this study Professor Wan and his group conducted all synthesis and spectroscopic analysis, including the photochemical analysis. In a similar study although not with biphenyls, the a-azidocinnamates were investigated in collaboration with Professor Meth-Cohn of the University of Sunderland. Professor Meth-Cohn and his group conducted all synthesis and spectroscopic analysis. The biphenyl type compounds have also been studied using database analysis to examine the bond lengths, torsion angles, inter-/intra-molecular interactions and general packing conformations and interactions within these structures and this analysis was used to study several conformational anomalies that exist in biphenyl derivative compounds. The second chemical type is carbaboranes; these compounds have been examined in collaboration with Professor Wade's group at the University of Durham. The analysis of carbaboranes centers mainly on hydrogen bonding however also expands into several novel carbaborane structures. Professor Wade and his group carried out the synthesis and spectroscopic analysis.
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Iannarelli, Paul M. "Routes to novel azo compounds." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/3492.
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Routes to novel heterocyclic azo compounds and components of use as potential inkjet dyes were investigated. A new route to fluorenones from biphenyl acid chlorides using FVP (Flash Vacuum Pyrolysis) has been discovered. Fluorenone and 4-methylfluoren-9-one were prepared by FVP of 2-phenylbenzoyl chloride and 2-methylbiphenyl-2-carbonyl chloride respectively. Xanthen-9-one and thioxanthen-9-one were also prepared by FVP from the corresponding acid chlorides. 9-Phenanthrol could also be prepared via the FVP of biphenylacetyl choride and the application of this method to a heterocylic thiophene system afforded naphtho[1,2-b]thiophen-4-ol. Naphtho[2,1-b]thiophen-4-ol and naphtho[1,2-b]furan- 4-ol could be obtained in low yields by the FVP of (2-thiophen-3-ylphenyl)acetic acid methyl ester and (2-furan-2-ylphenyl) acetic acid methyl ester over a tungsten trioxide catalyst. Coupling of these systems with the diazonium salt of Acid Yellow 9 afforded the corresponding azo compounds. New heterocyclic dyes were also prepared from the condensation of heterocyclic hydrazines with 4,9-disulfophenanthrenequinone. Pyridine, pyridazine, phthalazine, isoquinoline and 2-quinoline disulfophenanthrene quinone metallised 2:1 nickel complexed magenta dyes were prepared. Industrial tests by standard methods revealed the pyridazine dye has a particularly impressive balance of light and ozone fastness over similar magenta dyes. The reaction of an arylnitro compound with 2-aminopyridine appeared to be an attractive and high yielding route to 2-(phenylazo)pyridine. However, application of this reaction to substituted and naphthalene systems failed. This afforded byproducts due to nucleophilic substitution of groups such as methoxy and the relatively uncommon nucleophilic substitution of hydrogen with none of the required azo products obtained. Therefore it appeared that the reaction of a nitro and amine was not a robust and versatile route to heterocyclic azo compounds. An alternate route to heterocyclic azo compounds involved the use of the Mills reaction by the condensation o-anisidine, p-chloroaniline, 2-aminophenol, 3- aminophenol, naphthylamine, 8-amnioquinoline and 2-acetylamino-5-aminobenzenesulfonic acid with 2-nitrosopyridine afforded the heterocyclic azo products in moderate to high yields. The Mills reaction does appear to be the favored route to heterocyclic azo compounds. Several factors were identified which affect the process of bisazo coupling of chromotropic acid and products obtained. Reaction at the ipso position of monoPACAs (2-phenylazochromotropic acid) leading to increased yields of the ipso substitution monoPACA by-product as opposed to the expected bisazo coupling position was a major problem. Studies indicated reactivity at the ipso position was greatly reduced by the presence of electron withdrawing groups around the phenyl ring of the monoPACA. Further study indicated reaction at the bisazo coupling position increased with the strength of the diazonium salt used in bisazo coupling. Therefore the electronic nature of the monoPACA starting material and the diazonium salt used in bisazo coupling greatly affected the products obtained. Reaction pH studies also revealed attack at the bisazo coupling position increases with pH and at lower pH (5.0 – 8.0) attack at the ipso position dominated. Reactivity of the monoPACA starting material also increased with pH. The influence of steric effects upon bisazo coupling revealed, in the cases where ortho sulfonic acid groups were present in the monoPACA, a reduction in attack at the ipso position. Hence the reaction appeared to be directed towards the required bisazo coupling position.
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Abuelyaman, Ahmed Salih. "Synthesis and evaluation of fluorescent and biotinylated derivatives of diphenyl peptidylphosphonate esters and biotinylated isocoumarins as inhibitors of serine proteases." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/27556.
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Hahn, Soonkap. "Double hydrogen bonding of 1, 8-biphenylenediol with various bases /." The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487260531954656.
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Ahn, Kyunghye. "Double hydrogen bonding of 1,8-biphenylenediol and its derivatives /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487266691094261.
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Haske, Wojciech. "Photophysics of bis(diarylamino)biphenyl dyes adsorbed on silver nanoparticles." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34787.
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This dissertation investigates the photophysics of bis(diarylamino)biphenyl (TPD) and silver nanoparticles (AgNP). A main goal of this work was to develop an understanding of the relaxation pathways involved in the deactivation of photoexcited TPD chromophores in close proximity to silver nanoparticles. The TPD chromophores were attached to the silver nanoparticle core via an alkylthiol group. The TPD-AgNP systems were synthesized and characterized using Transmission Electron Microscopy (TEM), UV-visible absorption, infrared spectroscopy, and Nuclear Magnetic Resonance (NMR) spectroscopy, Inductively Coupled Plasma - Emission Spectroscopy (ICP-ES) and Thermogravimetric Analysis (TGA). Time-resolved photophysical processes in these systems were studied using femtosecond transient absorption spectroscopy.
Initial studies of the interaction of the TPD and AgNP addressed the linker length dependence of the dye excited state decay kinetics, wherein alkyl linker chains of 3, 4, 8 and 12 carbon atoms were used. These results showed that an ultrafast deactivation of the excited state of the TPD chromophore, which is three orders of magnitude faster than that of the free chromophore in solution, occurred in all of the systems. However, an unexpected new transient species was observed for the systems with three and four carbon linker chains. Further studies showed this species to be spectroscopically very similar to the TPD radical cation, suggesting a charge separation pathway in the excited state relaxation. Possible pathways for formation of the cation-like state were examined through comparisons to the photophysics of alkyl substituted TPD in solution and in solid films, investigation of the pulse energy and TPD surface coverage dependence of the yield of the cation-like TPD species, transient absorption anisotropy decay dynamics, and kinetic modeling studies. Taken together, these investigations provide support for exciton-exciton annihilation being responsible for the formation of cation-like species. The packing of the TPD chromophores is concluded to be of critical importance in the generation of the cation like species but it is also possible that proximity to the silver nanoparticle plays a role in facilitating charge separation as well.
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Yang, Lei. "Combined Electrochemistry and Spectroscopy of Complexes and Supramolecules containing Bipyridyl and Other Azabiphenyl Building Blocks." Thesis, University of North Texas, 1995. https://digital.library.unt.edu/ark:/67531/metadc279396/.
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A group of azabiphenyl complexes and supramolecules, and their reduced and oxidized forms when possible, were characterized by cyclic voltammetry and electronic absorption spectroscopy. The oxidized and reduced species, if sufficiently stable, were further generated electrochemically inside a specially designed quartz cell with optically transparent electrode, so that the spectra of the electrochemically generated species could be taken in situ. Assignments were proposed for both parent and product electronic spectra. Species investigated included a range of Ru(II) and Pt(II) complexes, as well as catenanes and their comparents. Using the localized electronic model, the electrochemical reduction can be in most cases assigned as azabiphenyl-based, and the oxidation as transition metal-based. This is consistent with the fact that the azabiphenyl compounds have a low lying π* orbital. The electronic absorption spectra of the compounds under study are mainly composed of π —> π* bands with, in some cases, charge transfer bands also.
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Ehsan, Sadia. "Simultaneous mobilization of polychlorinated biphenyl compounds and heavy metals from a field contaminated soil." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100355.
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A major factor complicating the cleanup at many sites is co-contamination by both organic compounds and heavy metals. Whereas much research has focused on the removal of either organic compounds or metals, relatively few studies have investigated simultaneous removal of organic and inorganic pollutants from soil.The studies reported in this thesis have evaluated a novel technique for the simultaneous mobilization of polychlorinated biphenyl (PCB) compounds and heavy metals (HMs) from a field contaminated soil. Soil extraction with washing aids {surfactants/cyclodextrin in combination with chelating reagent(s)} was optimized for mobilization efficiency, recovery/recycle of washing additives, and in parallel detoxification of mobilized contaminants. PCB extraction efficiencies were determined with a method that converted all the PCB congeners to dicyclohexyl by hydrogenation over palladium. Studies demonstrated that 10 minutes of ultrasonic mixing of field contaminated soil with a combination of surfactant (30 mL L-1) or cyclodextrin (100 g L-1) and a sparing quantity (2 mmoles) of EDTA, simultaneously mobilized appreciable quantities of PCBs and most analyte metals (Cd, Cu, Mn, Pb, Zn, Ni, Cr).
Relative to individual reagents, combinations of surfactant (Brij 98, Triton X-301, or Triton XQS-20) or cyclodextrin (RAMEB or HPCD) with EDTA did not influence PCB extraction efficiencies perceptibly. The presence of surfactant or cyclodextrin in admixture with EDTA did not appreciably change the efficiency of mobilization of most heavy metals (Al, Cd, Cr, Fe, Mn, Ni, and Zn) but did increase the recovery of Cu and Pb with nonionic surfactant and cyclodextrin. When coupled with PCB removal by hexane back-extraction and precipitation of the HMs (mediated by hydrolysis of zero-valent magnesium (Mg0)}, aqueous washing suspension was regenerated and recycled twice to mobilize more contaminants from the soil. Three sonication-washes with the same charge of reagent mobilized appreciable quantities of PCBs (68 - 83%) and virtually all of the available Cd, Cu, Mn, and Pb and lesser amounts of the Zn (56%), Ni (59%), and Cr (50%) but only small quantities of Al (28%) and Fe (30%).
The release of EDTA from heavy metals complexes was efficient for most metals (99%) but was influenced by the nature of surfactant. EDTA recovery (62-65%) post three cycles of soil washing, hexane back-extraction, and Mg 0 treatment was similar for all reagent combinations. Among surfactants and cyclodextrin, only anionic surfactants suffered losses to Mg0 treatment.
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Eagle, Andrew John. "The synthesis and study of some novel carbohydrate and biphenyl compounds for mesomorphic properties." Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317612.
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Severinsen, Rune. "Development of solid-phase chemistries to access libraries of biphenyl privileged substructures /." Cph. ; Måløv : Department of Medicinal Chemistry, The Danish University of Pharmaceutical Sciences : Medicinal Chemistry Research III, Novo Nordisk A/S, 2005. http://www.dfh.dk/phd/defences/RuneSeverinsen.htm.
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Hilton, Cameron L. "Biphenyl complexes of zirconium and their utility in the synthesis of polycyclic aromatic hydrocarbons." abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3326203.
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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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Hurtz, III Donald. "Comparing the Serum Levels of Polychlorinated Biphenyl Compounds between the Residents of Calcasieu Parish and Lafayette Parish, Louisiana." Digital Archive @ GSU, 2007. http://digitalarchive.gsu.edu/iph_theses/22.
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In 2001, a population-based cross-sectional study was conducted to compare levels of total polychlorinated biphenyls (PCBs) in residents of Calcasieu Parish and Lafayette Parish, Louisiana. A demographic, lifestyle, and food consumption questionnaire was collected for each participant. Overall, weighted geometric means and medians of total serum PCB concentrations in residents of Calcasieu and Lafayette Parishes were similar among all risk subgroups. However, 15-29 year olds had higher total serum PCB weighted geometric means in Calcasieu (64.4 ppb) than did this age group in Lafayette (46.6 ppb) (p=0.0059); conversely, in the 60 and older age group, geometric means of 293.7 ppb and 392.5 ppb were observed for Calcasieu and Lafayette, respectively (p=0.0059). In general, total PCB serum levels in Calcasieu and in Lafayette Parish, Louisiana residents were similar to each other and to levels observed in the U.S. general population in this time period.
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李昌運 and Cheong-wan Lee. "Time-resolved resonance Raman and density functional theory investigation of the T1 triplet states and radical cations ofsubstituted biphenyl compounds." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31224623.
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Lee, Cheong-wan. "Time-resolved resonance Raman and density functional theory investigation of the T1 triplet states and radical cations of substituted biphenyl compounds." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22956311.
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Daso, Adegbenro Peter. "The occurrence of brominated flame retardants (polybrominated diphenyl ethers and polybrominated biphenyl) in the Cape Town environment." Thesis, Cape Peninsula University of Technology, 2011. http://hdl.handle.net/20.500.11838/2010.
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Thesis (DTech (Environmental Health))--Cape Peninsula University of Technology, 2011.This study was aimed to provide baseline information about the environmental levels of selected PBDEs (BDE 28, 47, 100, 99, 154, 153, 183 & 209) and BB 153 in different matrices, including wastewater treatment plants' effluent, sludge, landfill leachate, river water and bottom sediment samples from different locations within the City of Cape Town. The monitoring of these contaminants was carried out bi-monthly over an extended period of 12 months beginning from April 2010 to March 2011. In this study, a total of 63, 168, 312, 93 and 108 samples for leachate, wastewater treatment plant (WWTP) sludge, effluent, river water and bottom sediment, respectively were collected from three landfill sites, four WWTPs and two rivers within the City of Cape Town. The aqueous matrices were extracted using a liquid-liquid extraction technique. The extraction of both sediment and sludge samples were performed using mechanical shaking and soxhlet extraction techniques, respectively. Extract obtained were further purified using multi-layer silica gel column chromatographic technique. The routine analysis of these target compounds was carried out using a gas chromatograph equipped with an electron capture detector (GC-µECD). However, the structural elucidation of these compounds was performed with a gas chromatography-time of flight-mass spectrometry (GC-TOF-MS) instrument.
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McDougal, Rebecca, and n/a. "DDT residue degradation by soil bacteria." University of Otago. Department of Microbiology & Immunology, 2007. http://adt.otago.ac.nz./public/adt-NZDU20070914.142931.
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1,1,1-trichloro-2,2-bis(4-chlorophenyl)-ethane (DDT) residues (DDTr) are widespread and persistent environmental contaminants, and have been classed as priority pollutants by the United Nations Environment Programme (UNEP). DDTr are potent endocrine disrupting molecules, and have been associated with reproductive abnormalities in juvenile alligators and rats. Microorganisms that metabolise DDTr both aerobically and anaerobically have been isolated and characterised. Bacteria that degrade DDTr aerobically typically utilise a dioxygenase to initiate degradative reactions through ring-hydroxylation, and convert DDTr to 4-chlorobenzoate without further degradation. Terrabacter sp. strain DDE-1 was isolated from DDTr-contaminated soil from Canterbury, New Zealand, and aerobically degrades 1,1-dichloro-2,2-bis-(4-chlorophenyl)-ethylene (DDE) to 4-chlorobenzoate, when grown in the presence of biphenyl (BP). The intermediates of degradation were inferred to be the end products of dioxygenase activity. Sequencing of a large linear plasmid, pBPH-1, from strain DDE-1 identified a cluster of genes with high levels of sequence similarity to BP-degradation genes from Rhodococcus spp. and Pseudomonas spp. This plasmid is lost at high frequency producing the plasmid-cured strain MJ-2, which has lost the ability to degrade BP or DDE. The aim of this study was to confirm that DDE-degradation in strain DDE-1 is encoded by the bph operon located on pBPH-1. No genetic systems to study gene function in either DDE-1 or MJ-2 could be developed using an array of broad-host range vectors. However, heterologous expression of the bph genes in Rhodococcus erythropolis strain TA422 was successful, with the recombinant strain TA425, obtaining the ability to utilise BP and DDE as a sole source of carbon and energy. DDE-1 was shown to convert indole to indigo, but MJ-2 could not, indicating that the biphenyl dioxygenase located on pBPH-1 is responsible for this activity. The bph genes from strain DDE-1 also conferred the ability to produce indigo from indole on strain TA425, confirming successful expression of the functional biphenyl dioxygenase in this strain. Despite several attempts to show quantitative degradation in strain TA425 using gas chromatography, the results were inconclusive Further analysis is needed to provide unequivocal evidence of DDE-degradation by strain TA425. Attempts to express the bph genes in rhizosphere-colonising bacteria, such a Rhizobium spp. or Pseudomonas spp., were unsuccessful, as evidenced by the inability to produce indigo, hence the lack of a functional biphenyl dioxygenase. However, RT-PCR did indeed indicate that P. aeruginosa strain Fin1 produced a bphA1 transcript, indicating that an error is occurring post-transcriptionally in these strains, to prevent production of the functional enzyme.
New Zealand has recently been shown to contain hotspots of DDTr-contamination. The second aim of this study was to determine the prevalence of DDTr-degrading bacteria and to gain insight into the types of bacteria that inhabit sites contaminated with DDTr. To investigate this, culture-dependent and culture-independent techniques were employed. Enrichment for DDTr-degrading bacteria yielded species of Rhodococcus and Ralstonia using DDTr-overlayer plate assays. The polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) were used to amplify and analyse the 16S rDNA and 16S rRNA for the identification of dominant and active bacteria in soil samples. The results of this analysis identified bacteria such as Williamsia spp. and Gordonia spp. that degrade other types of pollutants. This analysis did not identify a predominance of Rhodococcus or Ralstonia spp., or other bacteria that have been shown to degrade DDTr. To identify ecologically relevant members of the bacterial communities in DDTr-contaminated soils, and potentially important metabolic pathways, identification of ring-hydroxylating dioxygenase (RHD) genes was performed. PCR and restriction fragment length polymorphism (RFLP) analysis were employed together with phylogenetic analyses. The results showed that the RHD genes identified, clustered separately to those genes previously characterised from cultivated bacteria. Among these genes, one phylogenetic group was most closely related to the dioxygenase genes from Ralstonia eutropha H850, which is potent PCB-degrading bacterium that possesses a dioxygenase with a wide substrate range for many types of heavily chlorinated, PCB congeners. The identification of a predominance of genes with similarity to phenyl-propionate dioxygenases has been not been recognised previously in soil studies.
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Lundgren, Kjell. "Properties and analysis of dioxin-like compounds in marine samples from Sweden." Doctoral thesis, Umeå universitet, Kemiska institutionen, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-24.
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Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) have been assigned toxic equivalency factors (TEFs). These compounds are today routinely analysed with sophisticated analytical techniques. In a near future, there might be other dioxinlike compounds such as polychlorinated naphthalenes (PCNs), alkyl-polychlorodibenzofurans (R-PCDFs), and polychlorinated dibenzothiophenes (PCDTs) added to this list of toxic dioxin-like compounds. It is therefore important to have a readiness to analyse these new compounds in environmental samples. In this study, a multi-residue non-destructive analytical method for the analyses of these planar dioxin-like compound classes was developed. The use of HPLC PX-21 carbon column fractionation enabled the separation of interfering PCBs from coplanar PCBs and other planar dioxin-like compounds of interest. The obtained planar fraction containing the dioxin-like compounds was analysed using high-resolution GC-MS. Levels of PCNs in surface sediments and settling particulate matter in the northern Baltic Sea were determined. The concentrations of PCNs in background surface sediments were approximately 1 ng/g dw and the estimated PCN fluxes were similar to the pre-industrial levels determined in Europe. The PCN congener patterns in the surface sediments suggest that the PCNs deposited in the Baltic Sea originate from similar sources. Bioaccumulation of PCNs in a benthic food chain (sediment, amphipod, isopod, and four-horned sculpin) from the Gulf of Bothnia was studied. The results indicated that only a few PCN congeners biomagnified. The highest biomagnification factors (BMFs) were found for 2,3,6,7-substituted congeners and those lacking adjacent hydrogen-substituted carbon atoms. The calculated biota to sediment accumulation factors (BSAFs) showed that the tetra- and penta- CNs exhibited BSAF values higher than one, while BSAFs for the more chlorinated PCNs were less than one. A general difference between the northern and southern parts of the Gulf of Bothnia could be seen in the samples, with the lowest PCN and total PCB concentrations being found in the north and the highest in the south. This gradient is related to distance from the more industrialised and populated regions in the southern parts of Sweden and Finland, and central Europe. Analysis of R-PCDFs in crustacean samples from the Swedish west coast was performed using HRGC-MS/MS. The ΣR-PCDFs in these samples were present at concentrations up to 10 times higher than the ΣPCDFs. The relatively high concentrations of R-PCDFs in the crab samples demonstrate that these compounds bioaccumulate. The fate of a pollutant in the environment and the toxicity of a compound are governed by its physicochemical properties. The information found in a data set of properties can predict a compound’s mode of action. The following physicochemical properties for 87 PCDFs were measured: ultra-violetadsorption, relative retention times on two common gas chromatographic stationary phases, and relative mass spectrometric response factors using EI- and NCI- modes.
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Yu, Liang 1978. "Washing to detoxify soil burdened with PCB compounds." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101693.
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Polychlorinated biphenyls (PCBs) are a group of 209 chemical congeners that are toxic and persistent organic contaminants---they have been present in the environmental for several decades. Sites contaminated with PCBs pose serious health and safety risks to the surrounding environment due to their toxicity, persistence and bioaccumulation in creature. Polychlorinated biphenyls were commercially produced complex mixtures for a variety of applications. Before production was discontinued world-wide in 1977, several million tons of PCBs have been directly disposed to the soil. Researchers have been encouraged to develop novel techniques/approaches to detoxify PCB compounds and PCB contaminated soil. Ideally, these methods would be inexpensive, rapid, efficient and environmentally benign.This study investigated novel approaches/techniques for PCB hydrodechlorination with noble metal catalyst in a continuous hydrogenation system, using a reactor column filled with Pd0/gamma-Al2O3 catalyst. Appreciable quantities of PCB compounds or other aromatic compounds were hydrodechlorinated and/or hydrogenated under mild conditions (90°C). The reaction efficiency was virtually complete if sufficient H2 was included in the mobile phase either by pure H2 or supercritical CO 2 combined with 5% H2.
The study also optimized conditions to wash PCBs washing condition from contaminated soil by sonication mixing and outlined an environmentally benign industrial application that combined soil washing with an at line PCBs hydrodechlorination process. The techniques/approaches developed in this study would seem to have a broad application in PCB dechlorination/detoxification and in the remediation of historically contaminated soil/sediments.
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Admire, Brittany. "The Estimation of Biologically and Environmentally Relevant Properties of Organic Compounds." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/556008.
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The UPPER (Unified Physicochemical Property Estimation Relationships) model uses additive and non-additive parameters to estimate 21 biologically and environmentally important physicochemical properties of organic compounds. Thermodynamically sound relationships are used to predict boiling and melting points, aqueous and octanol solubilities, vapor pressure and the air-octanol, air-water and octanol-water partition coefficients. These properties determine the distribution and fate of organic compounds in biological and environmental systems. The model has been validated on a data set of 2000 hydrocarbons and polyhalogenated hydrocarbons, provides a simple and accurate method to predict the properties studied.
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Awad, Andrew Magdi. "Particulate and gas-phase PCBs and OH-PCBs in Chicago air." Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/2038.
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This study extends the work we have previously done by reporting on both gas-phase and particulate phase PCB concentrations in Chicago air as well as giving a first report on airborne OH-PCBs in Chicago. Gas phase PCB concentrations ranged from 43.1 pg/m³ to 2250 pg/m³, with an average concentration of 594 pg/m³ ± 445 pg/m³, and exhibited strong temporal trends. Particulate phase PCBs accounted on average for 4.3% of total PCBs in a sample. OH-PCBs were detected in both the gas and particulate phase and exhibit characteristics of either emission sources or atmospheric reactions depending on the congener.
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Morgan, Marisa L. "Exposure to Endocrine Disrupting Compounds and Reproductive Toxicity in Women." FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1586.
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The overall objective of the research presented in this dissertation was to assess exposure to endocrine disrupting chemicals (EDCs), polychlorinated biphenyls (PCBs), phthalates, and bisphenol A (BPA) in the general population and evaluate their associations with adverse reproductive health effects, including cancers, in women. Given the proven contribution of unopposed estrogens to the risk for endometrial neoplasia or breast cancer, renewed health concerns have aroused about estrogen mimicking EDCs found in food, personal care products or as environmental contaminants. Our meta-analysis showed that exposure to estrogen mimicking PCBs increased summary risk of breast cancer and endometriosis. We further evaluated the relationship between endometriosis and breast cancer, and EDCs using a bioinformatics method. Our bioinformatics approach was able to identify genes with the potential to be involved in interaction with PCB, phthalates and BPA that may be important to the development of breast cancer and endometriosis. Therefore, we hypothesized that exposure to EDCs such as PCBs, phthalates, and BPA, results in adverse reproductive health effects in women. Using subject data and biomarkers available from the Center for Disease Controls National Health and Nutrition Examination Survey database we conducted a cross-sectional study of EDCs in relation to self-reported history of endometriosis, uterine leiomyomas, breast cancer, cervical cancer, ovarian cancer, and uterine cancer. Significantly higher body burdens of PCBs were found in women diagnosed with breast cancer, ovarian cancer, and uterine cancer compared to women without cancer. PCB 138 was significantly associated with breast cancer, cervical cancer, and uterine cancer, while PCBs 74 and 118 were significantly associated with ovarian cancer. The sum of dioxin-like PCBs were significantly associated with ovarian cancer (OR of 2.02, 95% CI: 1.06-3.85) and the sum of non-dioxin-like PCBs were significantly associated with uterine cancer (OR of 1.12, 95%CI: 1.03-1.23). Significantly higher body burdens of PCBs were also found in women diagnosed with endometriosis and uterine leiomyomas. Documenting the exposure to EDCs among the general U.S. population, and identifying agents associated with reproductive toxicity have the potential to fill research gaps and facilitate our understanding of the complex role environmental chemicals play in producing toxicity in reproductive organs.
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Rodrigue, Jean. "Utilisation du canard de Pékin (Anas platyrhynchos) comme bioindicateur de la contamination du milieu naturel par les substances bioaccumulables." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22796.
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Eighteen-month-old adult female Peking Ducks (Anas platyrhynchos) were placed in the Ottawa, and St. Lawrence rivers for periods varying between 14 and 72 days during the summers of 1987, 1988 and 1989. Two stations located on Lake St. Francis were selected for establishing a time-curve for the accumulation of organochlorine pesticides (OC) and PCB in the liver. The ducks rapidly lost weight during their first 20 days in the natural environment but stabilised after about 40 days. This weight loss was caused by the stress of habitat, change, the energetic costs in searching for food and moulting.There was a rapid increase in the number and concentration of contaminants detected in the livers of ducks exposed to pollutants in the natural environment. The concentrations found were low (99.9% of OC-PCB are under 1 mg/kg wet weight basis). These individuals were generally from 10 to 1000 times more contaminated than the control ducks for 40 days of exposure.
The use of domestic ducks as bioindicators has several advantages. They can be obtained readily and cheaply, and the sex and age of the individuals can be controlled. Since they are not very mobile and therefore are easy to locate, they provide information on the contamination (metals or OC-PCB) of specific sites. The use of Peking ducks has some limitations. There is a need for appropriate habitats to ensure their survival, and there is considerable stress caused by transferring the ducks from the breeding farm to the natural environment, thereby obliging them to search for food and exposing them to predators and poachers. (Abstract shortened by UMI.)
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Augulyte, Lijana. "Use and Development of Diffusive Samplers to Analyse the Fate of Polycyclic Aromatic Compounds, Polychlorinated Biphenyls and Pharmaceuticals in Wastewater Treatment Processes." Doctoral thesis, Umeå : Department of Chemistry, Umeå University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1912.
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Öberg, Mattias U. L. "Health risk assessment of dioxin-like compounds in complex samples /." Stockholm : Karolinska inst, 2003. http://diss.kib.ki.se/2003/91-7349-692-8.
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Sundqvist, Kristina. "Sources of dioxins and other POPs to the marine environment : Identification and apportionment using pattern analysis and receptor modeling." Doctoral thesis, Umeå universitet, Kemi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-22266.
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In the studies underlying this thesis, various source tracing techniques were applied to environmental samples from the Baltic region. Comprehensive sampling and analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in surface sediments in Swedish coastal and offshore areas resulted in a unique data set for this region. Nearly 150 samples of surface sediments were analyzed for all tetra- to octa-chlorinated PCDD/Fs. The levels showed large spatial variability with hotspots in several coastal regions. Neither Sweden nor the EU has introduced guideline values for PCDD/Fs in sediment, but comparisons to available guidelines and quality standards from other countries indicate that large areas of primarily coastal sediments may constitute a risk to marine organisms. Multivariate pattern analysis techniques and receptor models, such as Principal Component Analysis (PCA) and Positive Matrix Factorization (PMF), were used to trace sources. These analyses suggested that three to six source types can explain most of the observed pattern variations found in the sediment samples. Atmospheric deposition was suggested as the most important source to offshore areas, thus confirming earlier estimates. However, spatial differences indicated a larger fraction of local/regional atmospheric sources, characterized by PCDFs, in the south. This was indicated by the identification of several patterns of atmospheric origin. In coastal areas, the influence of direct emission sources was larger, and among these, chlorophenol used for wood preservation and emissions from pulp/paper production and other wood related industry appeared to be most important. The historic emissions connected to processes involving chemical reactions with chlorine (e.g. pulp bleaching) were found to be of less importance except at some coastal sites. The analysis of PCDD/Fs in Baltic herring also revealed spatial variations in the levels and pollution patterns along the coast. The geographical match against areas with elevated sediment levels indicated that transfer from sediments via water to organisms was one possible explanation. Fugacity, a concept used to predict the net transport direction between environmental matrices, was used to explore the gas exchange of hexachlorocyclohexanes (HCHs) and polychlorinated biphenyls (PCBs) between air and water. These estimates suggested that, in the Kattegat Sea, the gaseous exchange of HCHs primarily resulted in net deposition while PCBs were net volatilized under certain environmental conditions. The study also indicated that, while the air concentrations of both PCBs and γ-HCH are mostly dependent upon the origin of the air mass, the fluctuations in α-HCH were primarily influenced by seasonal changes.
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Petrich, Nicholas Thomas. "Simulating and explaining passive air sampling rates and analyte air concentrations for semi-volatile compounds on polyurethane foam disks." Thesis, University of Iowa, 2012. https://ir.uiowa.edu/etd/3513.
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Vale, Luiz Américo da Silva do. "Hidrodescloração catalítica de bifenilas policloradas (PCBs)." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/46/46132/tde-26112008-121816/.
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Bifenilas policloradas (PCBs) foram produzidas comercialmente entre 1929 e meados da década de 1980 para propósitos industriais. As mesmas propriedades que despertaram o interesse industrial, tais como: inércia química, alta constante dielétrica, resistência à queima; foram responsáveis pelo espalhamento dos PCBs em todos os compartimentos ambientais, de tal forma que são encontrados em amostras de tecidos adiposos de animais e humanos, leite, sedimentos dentre outras matrizes. Enormes quantidades de PCBs continuam em uso ou estão estocadas a espera de uma destinação final. No presente estudo demonstramos o uso da reação de hidrodescloração catalítica como forma de destruição/destoxificação de bifenilas policloradas. Para tanto, a reação foi estudada em amostras reais de PCBs (óleo dielétrico - Ascarel®), amostras comerciais (Aroclor® 1242 e 1254) e amostra sintética (2,4-diclorobifenila). O estudo se baseia no uso de solventes orgânicos como meio reacional e paládio suportado em carvão ativado como catalisador, devido à sua seletividade para a reação desejada, bem como sua baixa capacidade de hidrogenar compostos aromáticos. xii A condição experimental ótima para a hidrodescloração foi determinada a partir da aplicação de planejamento experimental do tipo Doehlert. Esta condição ótima foi aplicada com sucesso a PCBs contidos em outras matrizes. A cinética da reação é apresentada para o 2,4-diclorobifenila como estudo de caso e uma proposta de mecanismo da reação de hidrodescloração de PCBs é apresentada baseada nos resultados experimentais.Polychlorinated biphenyls (PCBs) were produced between 1929 and the 1980s for industrial applications. The same properties that make it a chemical of interest for industrial applications, such as: chemical inertness, high dielectric constant, fire resistance; were responsible for the widespreading of PCBs over all enviornmental compartments. They can be found in samples of fat tissues of humans and animals, milk, sediments, among other matrices. Enormous quantities of PCBs are still in use or stocked waiting for a final destination. In the present study, we have shown the use of catalytic hydrodechlorination as an alternative for the destruction/detoxification of polychlorinated biphenyls. For this, the reaction was studied in real samples of PCBs (dielectric oil - Ascarel®), commercial samples (Aroclor® 1242 e 1254) and pure chlorinated biphenyls (2,4-dichlorobiphenyl). The study is based in the use of organic solvents as reactional media and palladium supported in activated carbon as catalyst, due to its selectivity for the desired reaction and to its low capacity to hydrogenate aromatic compounds. xiv The optimal hydrodechlorination condition was determined through the application of a Doehlert experimental planning. This optimal condition was applied with success to PCBs contained in other matrices. The reaction kinetics for 2,4-dichlorobiphenyl was presented as a case study and a mechanistic proposal was presented for the hydrodechlorination of PCBs based on these experimental conditions.
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Utschakowski, Sven. "Anthropogene organische Spurenstoffe im Arktischen Ozean : Untersuchungen chlorierter Biphenyle und Pestizide in der Laptevsee, technische und methodische Entwicklungen zur Probenahme in der Arktis und zur Spurenstoffanalyse = Anthropogenic organic trace compounds in the Arctic Ocean /." Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1998. http://www.gbv.de/dms/bs/toc/253422019.pdf.
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Forns, i. Guzman Joan 1981. "Social and environmental determinants of neuropsychological development from birth to preadolescence." Doctoral thesis, Universitat Pompeu Fabra, 2012. http://hdl.handle.net/10803/96193.
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Introduction
Neuropsychological development is a genetically guided process which is continuously modified by socio-environmental factors. This thesis aimed to study the main socio-environmental determinants of neuropsychological development in different time-periods, such in the first two years of life, during preschool, and during preadolescence. This thesis also aimed to summarize the work done in environmental epidemiology on neuropsychological development in a novel conceptual framework.
Methods
This thesis is based on the data of the INMA (Infancia y Medio Ambiente) Project. The main objective of this project is to evaluate the impact of environmental exposures in children’s health in 7 population-based birth cohorts in different regions of Spain. The neuropsychological development of approximate total of 2,650 children was assessed at different time-periods following the same protocols.
Results
(1) Maternal cognitive capacities were positively related with child cognitive development early in life in more disadvantaged occupational social classes. (2) The levels of child cortisol were not related to child neuropsychological development during the second year of life. (3) Higher levels of long-chain polyunsaturated fatty acids in colostrum due to prolonged periods of breastfeeding improved early neuropsychological development of children, in particular in those children exposed to maternal smoking during pregnancy. (4) Prenatal exposure to PCBs (specially for PCB congener 153) impacted negatively on psychomotor development during the second year in life and on general neuropsychological development at the age of 4 years. (5) Postnatal exposure to organochlorine compounds was associated with a delay in reaction time (speed processing) during the preadolescent period. (6) The conceptual framework proposed will improve the quality of research in this area.
Conclusions
Social and cultural determinants such as maternal intelligence, educational level or occupational social class, are configuring the proximal environment in which a child develops and determine their neuropsychological development. Current levels of some organochlorine compounds, particularly polychlorinated byphenils, measured in blood samples (from umbilical cord, mothers, or children) are impairing on neuropsychological development in the general population.Introducció El desenvolupament neuropsicològic infantil és un procés guiat genèticament, el qual és contínuament influenciat per factors socials i ambientals. L’objectiu d’aquesta tesis fou l’estudi dels principals determinants socio-ambientals del desenvolupament neuropsicològic infantil en diferents períodes de temps. Aquesta tesis també té l’objectiu de resumir en un marc conceptual els diferents components del desenvolupament neuropsicològic pel seu ús en estudis d’epidemiologia ambiental. Mètodes Aquesta tesis està basada en dades del projecte INMA (Infancia y Medio Ambiente). El principal objectiu d’aquest projecte és avaluar l’impacte de les exposicions ambientals en la salud infantil en 7 cohorts de població establides en diferents regions d’Espanya. Dintre del marc d’aquest projecte, s’ha avaluat el desenvolupament neuropsicològic d’aproximadament 2.650 nens en diferents moments, seguint els mateixos protocols. Resultats (1) Les capacitats cognitives maternes estan positivament relacionades amb el desenvolupament cognitiu infantil en les primeres etapes, en les classes socials ocupacionals menys afavorides. (2) Els nivells de cortisol infantil no mostren associació amb el desenvolupament neuropsicològic durant el segon any de vida. (3) Nivells elevats d’àcids grassos poliinsaturats de cadena llarga en conjunció amb períodes prolongats de lactancia materna afavoreixen el desenvolupament neuropsicològic a les primeres etapes, especialment en aquells nens de mares fumadores durant l’embaràs. (4) L’exposició prenatal a PCBs (espcialment, al congener 153) impacta negativament en el desenvolupament psicomotor infantil durant el segon any de vida i en el desenvolupament neuropsicològic general als 4 anys d’edat. (5) L’exposició postnatal a compostos organocloroats està associada a una capacitat de reacció (velocitat de processament) més alentida en etapes preadolescents. (6) L’ús del marc conceptual propossat tesis afavorirà la qualitat de l’investigació en aquesta àrea. Conclussions Els determinants socials, com l’intel•ligència materna, el nivell educatiu o la classe social basada en l’ocupació, configuren l’entorn més proper del nen i determinen el seu desenvolupament neuropsicològic. Els nivells actuals de certs compostos organoclorats, especialment els bifenils policlorinats, mesurats en mostres de sang (de cordó umbilical, mares o nens) mostren efectes negatius sobre el desenvolupament neuropsicològic en la població general.
Introducción El desarrollo neuropsicológico infantil es un proceso guiado genéticamente, el cual está contínuamente influenciado por factores sociales y ambientales. El objetivo de esta tesis fue estudiar los principales determinantes socio-ambientales del desarrollo neuropsicológico infantil en diferentes periodos de tiempo. Esta tesis también tenía como objetivo resumir en un marco conceptual el trabajo hecho en epidemiología ambiental en el estudio del desarrollo neuropsicológico infantil. Métodos Esta tesis está basada en datos del proyecto INMA (Infancia y Medio Ambiente). El principal objetivo de esto proyecto es evaluar el impacto de las exposiciones ambientales en la salud infantil en 7 cohortes de población establecidas en diferentes regiones de España. El desarrollo neuropsicológico de aproximadamente 2.650 niños ha sido evaluado en diferentes momentos siguiendo los mismos protocolos. Resultados (1) Las capacidades cognitivas maternas están positivamente relacionadas con el desarrollo cognitivo infantil en edades tempranas en las clases sociales ocupacionales menos aventajadas. (2) Los niveles de cortisol en el niño no se asocian con el desarrollo neuropsicológico durante el segundo año de vida. (3) Niveles altos de ácidos grasos poliinsaturados de cadena larga debido a periodos largos de lactancia materna mejoraron el desarrollo neuropsicológico a edades tempranas, especialmente en esos niños cuyas madres fumaron durante el embarazo. (4) La exposición prenatal a PCBs (espcialmente para el congener 153) impacta negativamente en el desarrollo psicomotor durante el segundo año de vida y en desarrollo neuropsicológico general a la edad de 4 años. (5) La exposición postnatal a compuestos organoclorados está asociado con una peor capacidad de tiempo de reacción (velocidad de procesamiento) durante la preadolescencia. (6) El marco conceptual propuesto mejorará la calidad de la investigación en esta área. Conclusiones Los determinantes sociales tales como inteligencia maternal, nivel educativo o clase social basada en la ocupación, configuran el entorno más cercano en el cual el niño se desarrolla y determinan su desarrollo neuropsicológico. Los niveles actuales de ciertos compuestos organoclorados, especialmente los bifeniles policlorinados, medidos en sangre (de cordón umbilical, madre, o niño) tienen efectos negativos sobre el desarrollo neuropsicológico de la población general.
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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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Brunet, Sylvette. "Mode d'action des catalyseurs d'hydrodesazotation des coupes petrolieres : decomposition de quinoleines et d'anilines sur catalyseurs a base de sulfures de nickel et de molybdene." Poitiers, 1987. http://www.theses.fr/1987POIT2287.
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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.
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Bachelet, Delphine. "Biomarqueurs d'exposition aux composés organochlorés et risque de cancer du sein : analyse de l'étude cas-témoins en population générale CECILE basée sur l'utilisation de modèles pharmacocinétiques." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00807245.
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Le cancer du sein est le plus fréquent des cancers de la femme. Son incidence n'est expliquée que partiellement par les facteurs de risque bien établis comme les facteurs reproductifs, hormonaux ou génétiques. Plusieurs éléments suggèrent l'existence de facteurs de risque environnementaux, tels que les polluants organochlorés persistants connus comme perturbateurs endocriniens. Les objectifs de ce travail sont : d'étudier les niveaux d'exposition, et leurs déterminants, au DDE (principal métabolite de l'insecticide DDT) et aux polychlorobiphényles (PCB) ; d'estimer par une modélisation pharmacocinétique à base physiologique (PBPK) les niveaux d'exposition au PCB-153 à la période péri-pubertaire qui constitue une fenêtre de susceptibilité accrue de la glande mammaire aux agents environnementaux ; d'étudier le rôle du DDE et du PCB-153 dans le risque de cancer du sein, à la fois à partir de prélèvements sanguins actuels et, pour le PCB-153, à partir de niveaux estimés à la période péri-pubertaire.Ce travail a été effectué à partir de l'étude CECILE, étude cas-témoins en population générale incluant 1055 témoins et 1080 cas de cancer du sein diagnostiqués de février 2005 à mars 2008 dans les départements d'Ille-et-Vilaine et de Côte d'Or chez lesquels un prélèvement sanguin a permis d'effectuer des dosages de p,p'-DDE et de PCB-153. La modélisation PBPK mise en place en coopération avec une équipe de toxicologues canadiens a permis de simuler des profils toxicocinétiques vie entière de PCB-153 et d'estimer les niveaux d'exposition au cours de la puberté. Cette modélisation est basée sur les niveaux mesurés au moment de l'enquête, les facteurs individuels de variation (poids, taille, grossesses, allaitement) connus d'après le questionnaire et la courbe de contamination environnementale au cours du temps.Les niveaux de contamination biologique observés sont plus faibles que ceux rapportés précédemment dans les populations occidentales. Nous montrons également que les principaux facteurs prédictifs des niveaux sériques de p,p'-DDE et de PCB-153 chez les femmes incluent l'âge, les habitudes alimentaires, le poids et ses variations au cours du temps, les grossesses et l'allaitement, et le lieu de résidence. Nous n'observons pas d'association entre les niveaux de p,p'-DDE et le risque de cancer du sein, mais une association inverse apparaît pour les cancers du sein de type négatifs pour les récepteurs hormonaux. Nous observons également une association inverse avec les niveaux de PCB-153 chez les femmes de 50 ans et plus. L'association inverse est renforcée lorsque les niveaux sont estimés pour la période péri-pubertaire à l'aide des modèles PBPK chez les femmes de la génération 1951-1960, correspondant à la cohorte de naissance des femmes de plus de 50 ans ayant connu les expositions aux PCB les plus élevées durant leur puberté.Plusieurs mécanismes biologiques pourraient expliquer l'association inverse observée entre le cancer du sein et l'exposition aux PCB. Ces résultats doivent être confirmés par des études tenant compte des fenêtres de susceptibilité de la glande mammaire et constituent une piste intéressante à approfondir.
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Boukhalfa, Hakim. "Complexation du fer par des ligands tripodes à base de sous-unités 8-hydroxyquinoléine et 2,2'dihydroxybiphényle : aspects thermodynamiques et cinétiques." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10250.
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Ce travail concerne des etudes thermodynamiques et cinetiques de la complexation du fer(iii) par des ligands possedant des sites de coordination de type 8-hydroxyquinoleine et 2,2'-dihydroxybiphenyle. La premiere partie a concerne l'etude des complexes ferriques des ligands 8-hq (oxine), 5-so#3#, 8-hq (sulfoxine) et 5-f-8-hq (fluorooxine). Les resultats mettent en evidence l'influence des proprietes electroniques des sites de coordination sur la stabilite des complexes. Quand la coordination du fer par le ligand n'est pas complete, des hydroxo complexes sont formes. Les etudes cinetiques de formation et d'hydrolyse acide des complexes permettent une approche du mecanisme de formation et d'hydrolyse du complexe. Le mecanisme est exprime en terme d'une succession d'etapes de formation et de coupure des liaisons n-fe et o-fe. La seconde partie a ete consacree a l'etude thermodynamique et cinetique de la complexation de l'ion fe#3#+ avec des ligands de structure tripode o-trensox et n-trensox a sous-unites 8-hydroxyquinoleine. La caracterisation des ligands ainsi que des a permis de determiner les constantes d'equilibre et d'obtenir egalement des informations structurales a l'aide des methodes spectrophotometriques uv-vis, ir et potentiometriques. La cinetique de formation du complexe fe(o-trensox) en milieu acide ainsi que sa cinetique d'hydrolyse acide ont ete etudiees afin de mettre en evidence les mecanismes de complexation du fer par le ligand et de sa sortie de la cage de coordination formee par le ligand. Les resultats des etudes cinetiques d'echanges de l'ion fe#3#+ entre la transferrine, l'edta et o-trensox permettent de proposer un mecanisme pour l'echange du fer entre la transferrine et le ligand o-trensox. La troisieme partie concerne l'etude thermodynamique et cinetique de la complexation du fer par un ligand biphenol et son homologue tripode. Cette etude de physico-chimie en solution permet de mieux comprendre les interactions cations metalliques-ligands dans les perspectives de conception de molecules actives dans le domaine de la sante et de l'agrochimie
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Beaujolais, Virginie. "Cavités moléculaires chirales à groupements hydroxyles convergents : synthèses et étude de complexation." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10148.
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La complexation du fer est un probleme biologique fondamental, resolu chez les microorganismes par les siderophores, ligands de bas poids moleculaire aptes a solubiliser selectivement les ions ferriques, puis a livrer le metal a la cellule via des processus de reconnaissance complexes. Les siderophores synthetiques presentent a la fois un interet pour l'etude du metabolisme du fer et peuvent avoir des applications therapeutiques dans le cas des surcharges en fer. Un nouveau siderophore synthetique tripodal, base sur trois sous-unites chelatantes de type o,o'-dihydroxybiphenyle, a ete prepare et ses proprietes complexantes vis-a-vis des ions ferriques ont ete decrites. Les memes sous-unites chelatantes ont ete integrees a un systeme macrobicyclique dont la synthese est detaillee. D'autre part, la premiere cavite moleculaire chirale a six hydroxyles convergents est preparee a partir de sous-unites de type o,o'dihydroxybinaphtyle. Lors de la complexation de fe#3#+, ga#3#+ et cr#3#+, ce ligand permet un controle stereospecifique de la chiralite ( ou ) du centre metallique octaedrique cree. Ceci est mis en evidence par rmn et dichroisme circulaire et etaye par des calculs de mecanique moleculaire
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Gardes, Thomas. "Reconstruction temporelle des contaminations métalliques et organiques particulaires dans le bassin versant de l'Eure et devenir des sédiments suite à l'arasement d'un barrage. Reconstruction of anthropogenic activities in legacy sediments from the Eure River, a major tributary of the Seine Estuary (France) Flux estimation, temporal trends and source determination of trace metal contamination in a major tributary of the Seine estuary, France Temporal trends, sources, and relationships between sediment characteristics and polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in sediment cores from the major Seine estuary tributary, France Impacts à court-terme de l’arasement d’un barrage sur la morphologie du cours d’eau et la remobilisation de sédiments contaminés par les métaux traces Bioaccessibility of polycyclic aromatic compounds (PAHs, PCBs) and trace elements: Influencing factors and determination in a river sediment core." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR038.
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L’impact anthropique sur les cours d’eau a significativement augmenté suite à la révolution industrielle engagée par les pays occidentaux. Ainsi, les modifications de la géomorphologie des cours d’eau pour le stockage de l’eau et la navigation, la conversion des surfaces à des fins agricoles, industrielles et d’urbanisation illustrent cette pression environnementale, qui se traduit, en autre, par une augmentation de rejets de divers contaminants dans les compartiments environnementaux et notamment les rivières. Une part de ces rejets peut donc se retrouver dans les matières en suspension, considérées alors comme des puits de stockage, qui transitent dans les rivières. Les aménagements des rivières et notamment la construction de barrages favorisent alors la sédimentation de ces particules contaminées au cours du temps. Ces sédiments d’origines anthropiques, également appelés legacy sediments, sont donc les témoins des activités anthropiques et permettent de reconstruire les trajectoires temporelles des contaminations au sein des bassins versants. L’Eure, affluent majeur de l’estuaire de Seine, a connu d’importantes pressions anthropiques depuis le vingtième siècle. La reconstruction temporelle des pressions anthropiques a nécessité l’association de différentes approches méthodologiques : (i) une analyse diachronique des modifications morphologiques de la rivière a été menée, conjointement à (ii) une analyse de la dynamique sédimentaire et de la nature des dépôts sédimentaires par couplage de méthodes géophysiques, sédimentologiques et géochimiques, et à (iii) la mise en place d’un réseau de suivi du comportement hydro-sédimentaire avec un échantillonnage en continu des matières en suspensions. De profondes modifications géomorphologiques se sont produites en aval du bassin versant, avec pour principales conséquences un exutoire déplacé d’une dizaine de kilomètres en direction d’un barrage et la formation d’annexes hydrauliques favorisant l’accumulation de sédiments dès les années 1940. Ceux-ci ont permis de montrer que le bassin versant de l’Eure avait connu d’importantes contaminations dont les conséquences sont encore enregistrées malgré l’arrêt des activités ou usages. Les tendances temporelles des éléments traces métalliques et métalloïdes ont montré de fortes contaminations en As dans les années 1940 et des contaminations d’origines industrielles en Cr, Co, Ni, Cu, Zn, Ag et Cd durant les années 1960–1970, ainsi que des contaminations en Sb et Pb en 1990–2000. Ces dernières sont toujours enregistrées malgré l’arrêt des activités responsables des rejets, comme l’ont attesté les résultats issus des matières en suspension actuellement collectées dans le cours d’eau. A l’instar d’une majorité des métaux traces, les contaminants organiques, tels les HAPs, ont montré d’importantes contaminations durant les années 1940–1960, dont les signatures indiquent une origine majoritairement pyrogénique. Les PCBs ont montré des contaminations importantes lors de la période 1950–1970, en lien avec la production et les usages nationaux de mélanges composés en majorité de congénères faiblement chlorés. Enfin, l’intérêt porté à une troisième famille de contaminants organiques persistants, les pesticides organochlorés, a montré l’utilisation de lindane et du DDT notamment lors de la période 1940–1970, et a mis en avant d’une part une utilisation post-interdiction du lindane et d’autre part la présence d’un métabolite du DDT plusieurs décennies après l’arrêt d’utilisation de ce dernier, en lien avec l’augmentation de l’érosion des sols cultivésThe anthropogenic impact on rivers has significantly increased following the industrial revolutioninitiated by Western countries. Thus, changes in the geomorphology of rivers for water storage andnavigation, the conversion of land for agricultural, industrial and urbanization purposes illustrate thisenvironmental pressure, which results, among other things, in an increase in discharges of variouscontaminants into environmental compartments, particularly rivers. Therefore, part of these dischargescan end up in suspended particulate matter, which is then considered as storage wells, which transit inrivers. River development, particularly the construction of dams, encourages the sedimentation of these contaminated particles over time. These sediments of anthropogenic origin, also called legacy sediments, are therefore witnesses to human activities and make it possible to reconstruct the temporal trajectories of contamination within watersheds. The Eure River, a major tributary of the Seine estuary, has experienced significant anthropogenic pressures since the twentieth century. The temporal reconstruction of anthropogenic pressures has required the combination of different methodological approaches: (i) a diachronic analysis of the morphological modifications of the river was carried out, in conjunction with (ii) an analysis of the sedimentary dynamics and the nature of the sediment deposits by coupling geophysical, sedimentological and geochemical methods, and (iii) the setting up of a network for monitoring the hydro-sedimentary behaviour with continuous sampling of suspended particulate matter. Significant geomorphological changes have occurred in the lower reaches of the watershed, with the main consequences being an outlet moved some ten kilometres in the direction of a dam and the formation of hydraulic annexes favouring the accumulation of sediments as early as the 1940s. These made it possible to show that the Eure River watershed had experienced significant contamination, the consequences of which are still being recorded despite the cessation of activities or uses. The temporal trends of trace metal and metalloid elements showed strong contaminations in As in the 1940s and contaminations of industrial origin in Cr, Co, Ni, Cu, Zn, Ag and Cd in the 1960s and 1970s, as well as contaminations in Sb and Pb in 1990–2000. The latter are still recorded despite the cessation of the activities responsible for the discharges, as evidenced by the results from the suspended particulate matter currently collected in the river. Like most trace metals, organic contaminants such as PAHs showed significant contamination during the 1940–1960s, with signatures indicating a predominantly pyrogenic origin. PCBs showed significant contamination during the period 1950–1970, in connection with the production and national uses of mixtures composed mainly of low chlorinated congeners. Finally, interest in a third family of persistent organic contaminants, organochlorine pesticides, showed the use of lindane and DDT, particularly during the 1940–1970 period, and highlighted the post-ban use of lindane and the presence of a metabolite of DDT several decades after the cessation of its use, in connection with the increase in erosion of cultivated soils
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Chou, Shin-Ling, and 周希瓴. "Analysis Method and Biodegradation of Biphenyl Organic Compounds." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/09195703753587844936.
Full textAbstract:
碩士國立中興大學
土壤環境科學系所
97
Polycyclic aromatic hydrocarbons（PAHs）are ubiquitous in our environment and come mainly from the incomplete combustion and pyrolysis of fossil fuels, organic materials, and wood. Napthalene （NAP）is the simplest fused polycyclic aromatic hydrocarbon. On the other hand, due to the wide distribution of polybrominated diphenyl ethers （PBDEs） flame retardants in the diverse environmental media in the world, the environmental fate of bromodiphenyl ethers is of interest. Currently, little is known about the transformation of these compounds, and in particular, about the microbial potential to degrade them. A HS (headapace)-solid phase microextraction (SPME) has grown wide popularity in recently years for the analysis organic compounds in environmental samples. In this study, two kinds of commercially available fibers, 100 μm polydimethylsiloxane (PDMS) and 85 μm polyacrylate (PA), were evaluated through the extraction efficiency of NAP and PBDEs. The extraction time, extraction temperature and salt concentration of organic compounds were investigated for optimizing the SPME method. Increasing the temperature to 60 ℃ can increase the sensitivity of organic compounds and short the equilibrium time. The most suitable salt concentration was 30 %. The obtained regression coefficients are higher the 0.98. Detection limits of this method can be lower down to 0.01 mg/L. In this study, the degradation of three kinds of biphenyl organic compounds （naphthalene, diphenyl ether and monobrominatediphenyl ether） by Pseudomonas putida was investigated. With P. putida, the naphthalene was degraded by 70 % of the original level in 14 days. In presence of P. putida within 10 days, the biodegradation rates of naphthalene only, naphthalene with sodium salicylate and naphthalene with FeCl3 were 0.13, 0.25, and 0.16 day-1, respectively. However, during 10 days, biodegradation efficiency of naphthalene with FeCl3 was more than that with sodium salicylate. One the other hands, the degradation of diphenyl ether is obvious but not for monobrominatediphenyl ether with P. putida. For the biodegradation of 4-monobrominated diphenyl ether （4-BDE also call BDE-3）, the degradation of 4-BDE was investigated with aerobic and anaerobic sludges. Under aerobic conditions, toluene and diphenyl ether were used as auxiliary carbon sources to stimulate the biodegradation of 4-BDE. The biodegradation of 4-BDE with toluene around 57 % is higher than that around 37 % with diphenyl ether and around 44 % with 4-BDE only at 15 days. No diphenyl ether was observed, indicating probably 4-BDE oxidized in the aerobic sludge. In anaerobic biodegradation, the removal of 4-BDE is about 30 %~80 % within 12 days by village’s and community’s anaerobic bacterial communities in their sludges. The main biodegradation byproducts of 4-BDE were determined to be diphenyl ether and bromide ions, indicating debromination process in these anaerobic sludges. We investigated microbial degradation of mono-BDE by enriched anaerobic microbial consortia from Li-Ming and Chung-Hsing community anaerobic sludges. We used DGGE (denaturing gradient gel electrophoresis）to sieve 11 bands and 10 bands that were amplified from these bacterial 16S rRNA genes DNA by PCR(polymerase chain reaction) for the degradation experiments of PBDE from Chung-Hsing and Li-Ming anaerobic sludges, respectively. These microorganisms which may be able to degrade mono-BDE have different DGGE patterns. In both sludges, we found the Clostridium sp. which has the similarity about 70 % to 90 %. In these two anaerobic sludges, several microorgamisms disappeared after adding mono-BDE. Around 10 to 11 microorganism species have the tolerance or degradation ability for mono-BDE. In addition, these anaerobic sludges can not degrade DBDE（deca-brominated diphenyl ether, BDE-209） in one half year incubation. To increase the removal efficiency, two additional dosages of 0.025 g/mL and 0.05 g/mL ZVI （microscale zero-valent iron） were added into these biodegradation systems. In existence of 0.05 g/mL ZVI, ZVI dominates the degradation process. Comparing to DBDE only and 0.025 g/mL ZVI only systems, the microorganisms can enhance the degradation efficiency of PBDEs in 0.025 g/mL ZVI system. It shows that the combined ZVI and anaerobic microorganisms can increase DBDE degradation ability. In the anaerobic microorganism-ZVI system, DGGE profiles of Li-Ming and Chung-Hsing sludges showed 5 and 6 bands corresponding to different species. The microbial diversity in biodegradation system for DBDE is smaller than mono-BDE. These better understandings of biological degradation of brominated diphenyl ether can facilitate the biodegradation and the fate of these chemicals in the environment.
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King, Russell K. "Mechanistic studies of the photochemistry of biphenyl containing bichromophoric molecules and the synthesis of molecular rods composed of bicyclo[2.2.2]octane units bonded in a bridgehead to bridgehead manner." 1985. http://catalog.hathitrust.org/api/volumes/oclc/12266912.html.
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Thesis (Ph. D.)--University of Wisconsin--Madison, 1985.Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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"Synthetic studies of Schizandrin type lignans." Chinese University of Hong Kong, 1986. http://library.cuhk.edu.hk/record=b5885681.
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Sengani, David. "Bioremediation of polychlorinated biphenyls (PCBs) on contaminated soils : a case study of Rietvlei Farm Borehole No. 11, Limpopo Province, South Africa." Diss., 2015. http://hdl.handle.net/11602/632.
Full textAbstract:
MENVMDepartment of Ecology and Resource Management
Polychlorinated biphenyls (PCBs) are worldwide environmental pollutants which contaminate the environment through careless disposal practices and accidental spills or leakages from electrical transformers. These organic compounds are lipophilic chemicals soluble in fats, slightly soluble in water and readily bioaccumulated in the fatty tissues of fish, birds, animals and humans. The main objective of this study was to isolate and identify PCB degrading bacteria from PCB contaminated soils and test them for their degradation ability of PCBs in natural habitat conditions. Three bacteria species which comprise of Gram negative and Gram positive microorganisms were isolated and identified through biochemical tests, catalase tests, oxidase tests and morphological study and included Burkholderia cepacia, Pasteurella pneumotropica and Enterococcus faecalis. The results indicated that, there was an overall decrease of PCB concentration level and the readings ranged between -1.51 and -1.79 respectively for all the microorganisms. Enterococcus faecalis remove as much as 32% of PCBs in the contaminated soil samples. Whereas Pasteurella pneumotropica could remove 24% of PCBs, Burkholderia cepacia 21% of PCBs and the mixed culture removed 23%. Data showed that the 3 bacterial strains could tolerate high concentration of PCBs. The results provided the evidence that naturally occurring bacteria in soil contaminated with PCBs have the potential to degrade PCBs. Statistical analysis showed that there was a significant positive correlation between bacteria growth and treatment with a coefficient of (r) =0.1459 and p value <0.001.
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Chen, Shun-Chang, and 鄭順彰. "Study of liquid crystal compounds composed of cycloalkylmethanol and biphenyl carboxylic acid." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/65581679479363581635.
Full textAbstract:
碩士國立高雄師範大學
化學系
94
Abstract Our former research results indicate that molecules containing cycloalkyl ring as a terminal group can exhibit various liquid crystal phases. In order to study the relationship between the molecular structure and the liquid crystal phase behavior, several new liquid crystal compounds composed of cycloalkyl rings and core molecules without flexible alkoxy chain were synthesized and their liquid crystal properties was also studied. The compounds containing cyclobutyl methanol and cyclopropyl methanol moieties exhibit a monotropic N phase. The system of EDC and DMAP is a suitable condition for the esterfication of the compounds studied.
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Toledo-Velasquez, David. "Inclusion complex formation between [alpha]-cyclodextrin and symmetrical 4,4'-disubstituted biphenyl compounds." 1987. http://catalog.hathitrust.org/api/volumes/oclc/16521814.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1987.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 82-85).
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Paulson, Andrea. "Stability of complexes of [alpha]-cyclodextrin and symmetrical 4,4'-disubstituted biphenyl compounds." 1986. http://catalog.hathitrust.org/api/volumes/oclc/15531122.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1986.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 69-72).
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"Synthesis and electronic properties of oligo[2,7-biphenylenylene-(E)-vinylene]s." Chinese University of Hong Kong, 1995. http://library.cuhk.edu.hk/record=b5888579.
Full textAbstract:
by Raymond Chi-Yuen Kwong.Thesis (M.Phil.)--Chinese University of Hong Kong, 1995.
Includes bibliographical references (leaves 60-62).
Acknowledgements --- p.i
Abbreviations --- p.ii
Abstract --- p.iii
Chapter 1. --- Introduction --- p.1
Chapter 2. --- Synthetic Methodology for Arylenevinylenes --- p.12
Chapter 3. --- Result and Discussion --- p.15
Chapter 4. --- Conclusion --- p.42
Chapter 5. --- Experimental --- p.43
Chapter 6. --- References --- p.60
Chapter 7. --- Spectra
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"Facile synthesis and nonlinear optical properties of push-pull 5,15-diphenylporphyrins." 1997. http://library.cuhk.edu.hk/record=b5889221.
Full textAbstract:
by Marco Ming Yeung.Thesis (M.Phil.)--Chinese University of Hong Kong, 1997.
Includes bibliographical references (leaves 90-96).
ACKNOWLEDGMENTS --- p.i
ABSTRACT --- p.ii
CONTENTS --- p.iii
LIST OF FIGURES --- p.v
LIST OF TABLES --- p.vi
ABBREVIATIONS --- p.vii
Chapter 1. --- INTRODUCTION --- p.1
Chapter 1.1. --- Theoretical Background of Nonlinear Optics --- p.1
Chapter 1.2. --- Organic Nonlinear Optical Chromophores --- p.5
Chapter 1.3. --- Porphyrins as Nonlinear Optical Chromophores --- p.8
Chapter 1.4. --- Synthetic Aspects of Porphyrins --- p.16
Chapter 1.4.1. --- Porphyrin Substrates --- p.16
Chapter 1.4.2. --- Vilsmeier Formylation --- p.17
Chapter 1.4.3. --- Bromination --- p.21
Chapter 1.4.4. --- Knoevenagel Condensation --- p.24
Chapter 1.4.5. --- Palladium-mediated Cross-coupling --- p.25
Chapter 2. --- RESULTS AND DISCUSSION --- p.28
Chapter 2.1. --- "Preparation of 5,15-Diphenylporphyrinatonickel(II)" --- p.28
Chapter 2.2. --- "Vilsmeier Formylation of 5,15-Diphenylporphyrinatonickel(II)" --- p.30
Chapter 2.3. --- Preparation of Push-pull Porphyrins --- p.47
Chapter 2.4. --- Molecular Structures of 65 and76 --- p.59
Chapter 2.5. --- Nonlinear Optical Properties of Push-pull Porphyrins 65 and66 --- p.63
Chapter 2.6. --- Attempted Syntheses of Push-pull Porphyrin Trimer and Dimer --- p.65
Chapter 2.7. --- Conclusion --- p.69
Chapter 3. --- EXPERIMENTAL SECTION --- p.70
Chapter 3.1. --- General Methods --- p.70
Chapter 3.2. --- Physical Measurements --- p.70
Chapter 3.3. --- Preparation of Push-pull Porphyrins --- p.71
Chapter 3.4. --- Attempted Preparation of Push-pull Porphyrin Trimer and Dimer --- p.86
Chapter 4. --- REFERENCES --- p.90
APPENDIX A 1 H NMR Spectra of Porphyrins --- p.97
APPENDIX B Crystal Data for 65 and 76 --- p.115
APPENDIX C Computed Geometry of 65 and 66 from Semiempirical PM3(tm) Calculations --- p.131
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McCaffery, Leslie Francis. "The total synthesis of some lichen tridepsides and a diphenyl ether." Phd thesis, 1997. http://hdl.handle.net/1885/145406.
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Behin, Aein Niloufar. "Photochemical and photophysical studies of Excited State Intramolecular Proton Transfer (ESIPT) in biphenyl compounds." Thesis, 2010. http://hdl.handle.net/1828/2944.
Full textAbstract:
This Thesis aims to examine the effects of substituents on the adjacent proton accepting phenyl ring with respect to a new type of excited state intramolecular proton transfer (ESIPT) process discovered by Wan and co-workers. Therefore, a number of 2-phenylphenols 23-28 were synthesized with electron-donor and electron-acceptor substituents such as methyl, methoxy, and ketone moieties on the adjacent proton accepting phenyl ring.
The results obtained from examination of photochemical deuterium exchange showed that all derivatives except for ketone 27 underwent deuterium exchange (Фex = 0.019 - 0.079), primarily at the 2’-position on photolysis in D2O-CH3CN. In general, compounds with methoxy moiety (ies) on the adjacent proton accepting ring showed higher deuterium exchange yields.
Diol 28 has the potential to undergo photosolvolysis as well as ESIPT process since it has both a benzyl alcohol and a phenol chromophore on the same molecule. Irradiation of 28 in 1:1 H2O-CH3OH gave the corresponding methyl ether product in high yield. Photolysis of 28 in 1:1 D2O-CH3OH also showed that ESIPT competes very well with photosolvolysis. Thus, this work has established that ESIPT can compete efficiently with photosolvolysis.
Semi-empirical AM1 (examination of HOMOs and LUMOs) calculations show a large degree of charge transfer in the electronic excited state (except 27), from the phenol ring to the attached phenyl ring of the studied compounds. The AM1 calculation for ketone 27 showed that the carbonyl oxygen is more basic than the carbon atoms of the benzene ring, which explains the lack of deuterium exchange observed for 27.