Дисертації з теми "Phosphite esters"
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Malhiac, Catherine. "Synthèses sélectives à l'aide de réactifs siliciés (Phosphite-Acétals de cétène silylés). Applications à la préparation d'aminophosphonates et d'esters 2,3-difonctionnels." Rouen, 1993. http://www.theses.fr/1993ROUES007.
Повний текст джерелаMarriott, Robert Edward. "Accelerated cleavage of phosphate esters." Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/272476.
Повний текст джерелаCocks, Sarah. "The electrophilicity and chemistry of phosphate esters." Doctoral thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/16377.
Повний текст джерелаA series of phosphate esters containing the E.-nitrophenyl moiety as a leaving group were synthesised and their base catalysed hydrolysis and electron impact-induced fragmentations studied. Heterocyclic ester substituents were present in some of the substrates and in-this sense they were considered as models for a nucleotide molecule containing both the 11 energy-rich11 phosphate bond and the nitrogen heterocyclic ring. The relative reactivity of the phosphorus-E,-nitrophenoxide bond was taken as a probe for nitrogen (pyridyl or quinolyl) participation in the substitution reaction. Although the heterocyclic derivatives show that the introduction of the nitrogen centre increases the rate of base catalysed hydrolysis, the reactivity enhancement is. not significant and results probably from polar effects rather than from intra-molecular catalysis. A comparison of the mass spectra of the heterocyclic and carbocyclic analogues, reveal differences which are significant (in the pyridyl substrates) and dramatic (in the quinolyl substrate) with regard to the fragmentation involving the E.-nitrophenoxy radical expulsion and formation of the corresponding phosphorylium ion. Synthetic approaches towards dimethylaryl and dimethyl(arylalkyl) phosphates are discussed. Nucleophilic displacement at the methyl ester carbon, and in particular the oxygen+ nitrogen methyl group transfer in these substrates occurs readily, complicating the synthetic procedures and lowering the stability of products. Dimethyl-(2-pyridylmethyl) phosphate isomerises in water to the zwitterionic N-methylpyridinium derivative via bimolecular methylation. The kinetics of the reaction were studied and no evidence for intra-molecular methyl transfer was obtained. - ii - The isomerisation of dimethyl-(quinolin-8-yl) phosphate in water also provides evidence for the bimolecular methylation. The crystal and molecular structure of dimethyl-(quinolin-8-yl) phosphate was determined and has revealed that the orientation of the CH 3 groups in the crystal provide no indication for the occurrence of methyl transfer in the solid state. The dynamics of the prepared phosphate derivatives studied in solutions were also investigated by means of mass spectrometry. Fragmentation patterns and their relative contributions are presented and discussed. The effect of solvent on the rates of the reaction between trimethyl phosphate and i) pyridine and ii) 4-(dimethylamino)pyridine, was studied at 25 - 65°C using NMR techniques. The solvents used were DzO, CD30D, CD3CN and DzO/CD30D and DzO/CD3CN mixtures. Water (DzO) is the most effective medium for the methyl transfer reaction. We attribute this to the strong hydrogen bonding between water and the departing dimethyl phosphate anion in the transition state. Activation parameters obtained for the reactions in pure solvents confirmed our interpretation of the hydrogen bonding effect operating in the transition state. Fragmentation of S-arylethyl phosphates has been investigated. A novel feature is exhibited by S-arylethyl phosphorochloridates. They easily decompose thermally yielding 1-chloro-2-arylethanes and/or arylethylenes presumably via concerted C-O and P-Cl bond fission involving a phenonium ion intermediate and expulsion of a metaphosphate species.
Butt, Afshan Hena. "Syntheses of analogues of some important phosphate esters." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369394.
Повний текст джерелаBond, Dianne Ruth. "A structure-reactivity study of selected phosphate esters." Doctoral thesis, University of Cape Town, 1985. http://hdl.handle.net/11427/22521.
Повний текст джерелаA comparative X-ray analysis study of bis(4-nitrophenyl)-8-quinolinyl phosphate (4), 1-naphthyl-bis(4-nitrophenyl) phosphate (5) and 4-nitrophenyl -8-quinolinyl phosphate (5) was undertaken. In compound (4) donor-acceptor nitrogen-phosphorus interactions change the geometry of the molecule from tetrahedral to quasi trigonal bipyramidal, thus the structure may be considered as an "early stage" of the intramolecular displacement of the 4-ni trophenoxide group. In the diester (6) this interaction is replaced by intermolecular N+ -H...O- hydrogen bonding. In addition the intramolecular non-bonded potential energies of (4) and (5) were calculated and the minimum-energy conformations were compared with those determined by X-ray diffraction. These results confirm the differences observed in the intramolecular interactions operative in (4) and (5). The mass spectra of (4) and (5) are dramatically different with respect to the fragmentation involving expulsion of the 4-nitrophenoxy radical and formation of the corresponding phosphorylitum ion by nitrogen participation. Rate measurements for the base-catalysed hydrolysis of the first P-OPNP linkage show that (4) is not significantly more reactive than (5) and provide no evidence for intramolecular nucleophilic catalysis in the hydrolysis of (4). The crystal and molecular structure of 1-naphthyl acetate (7) was determined. Attempts to grow suitable crystals of 8-quinolinyl acetate (8) failed and therefore its structure could not be elucidated. Possible intramolecular nitrogen - carbonyl carbon interactions operative in (8) could therefore not be established.
Haffey, Samuel Fraad 1973. "Numerical models of phosphate esters in the Chattahoochee River." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/29405.
Повний текст джерелаIncludes bibliographical references (leaves 124-127).
A numerical model was constructed to assess the magnitude of organophosphoric acid triester sinks in the Chattahoochee River and to identify concentration patterns downstream of point source discharges. The model was built using WASP5 and supporting software packages. The model simulated mass transport of tri-butyl phosphate, tri (2-butoxyethyl) phosphate, and tri (2-chloroethyl) phosphate within a reach of the river bounded by Buford Dam and Northern Atlanta. Several potential mechanisms for the removal of the phosphate esters from the water column were considered. These were biodegradation, sorption to settling solids, volatilization, and oxidation by free radicals. Of the three phosphate esters considered by the model, tri (2-chloroethyl) phosphate was predicted to be the most resistant to degradation by natural attenuation processes. Tri (2- butoxyethyl) phosphate showed the most potential for degradation in surface waters. Biodegradation and sorption to settling solids were predicted to be the most effective processes for the removal of tri (2-butoxyethyl) phosphate. Concentration patterns at several locations downstream of point source discharges were predicted for the three compounds. Concentration patterns were found to be affected by the diurnal flow variation caused by the operation of two hydroelectric dams within the modeled reach.
by Samuel Fraad Haffey.
M.Eng.
Iagrossi, Anna. "Stereochemical studies of reactions of phosphate and thiophosphate esters." Thesis, University of Leicester, 1988. http://hdl.handle.net/2381/33748.
Повний текст джерелаTarrat-Iché, Nathalie. "Etude théorique des mécanismes d'hydrolyse des esters de phosphate." Toulouse 3, 2005. http://www.theses.fr/2005TOU30212.
Повний текст джерелаPhosphate esters play a fundamental role in many biological processes. Unfortunately, the detailed understanding of how monoesters hydrolysis reactions proceed is still subject of debate (this is largely due to the kinetic stability of phosphate monoesters). Modern quantum chemistry methods seems to be a good alternative to elucidate these reaction mechanisms. In this thesis, we have validated the use of quantum calculation (DFT/B3LYP) coupled with a continuum solvation model by studying hydrolysis mechanism of phosphate tri- and diesters. In these cases, the scientific community is unanimous on the fact that they involve pentacovalent phosphorane intermediate or transition state. The same approach is applied to the hydrolysis mechanism of phosphate monoesters. By comparison with the results obtained in the case of the di- and triesters, it is observed that the reactivity of a protonated ester can differ from that of its methylated derivative, for which a phosphorane “intermediate” is occuring
Walsh, Owen Anthony. "Computer simulation of phosphate ester hydrolysis reactions." Thesis, University of Oxford, 2001. http://ora.ox.ac.uk/objects/uuid:bf94b5d1-c550-4af5-849c-4438000450aa.
Повний текст джерелаLad, Chetan Shantilal. "Mechanics and reactivity of phosphate ester hydrolysis." Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269339.
Повний текст джерелаKeita, Ousainou Ansumana. "The synthesis of new phenylhydroxyiodonium phosphates from (diacetoxyiodobenzene) and dialkyl phosphates and their use in the α-phosphorylation of ketones to mono-ketol phosphates". University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1197558427.
Повний текст джерелаTossell, Katie Jayne. "Catalysis of phosphate ester hydrolysis through hydrogen bonding." Thesis, University of Sheffield, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.578696.
Повний текст джерелаZaluski, Jordan A. "Improved Synthesis of Bis (2,2,2-trifluoroethyl) Phosphono Esters." Youngstown State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1471443290.
Повний текст джерелаChernobryva, Mariya. "Development of metal-based catalysts for phosphate ester hydrolysis." Thesis, Queen Mary, University of London, 2016. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24631.
Повний текст джерелаYun, Joanne W. 1970. "Modelling studies of magnesium-dependent phosphate ester processing enzymes." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/38776.
Повний текст джерелаFry, Fiona Helen 1972. "Metal complexes based on macrocyclic ligands and their ability to hydrolyse phosphate esters." Monash University, School of Chemistry, 2002. http://arrow.monash.edu.au/hdl/1959.1/8279.
Повний текст джерелаKramer, Ulrike. "Complexation of divalent copper, zinc and calcium ions by phosphate esters in aqueous solution." Doctoral thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/17083.
Повний текст джерелаPATOIS, CARL. "Alkylation-metallation des esters et amides phosphoriques : la 1,3-dimethyl-2-oxo-1,3,2-diazaphospholidine precurseur d'acrylates z." Palaiseau, Ecole polytechnique, 1992. http://www.theses.fr/1992EPXX0005.
Повний текст джерелаWilliams, Daniel M. "Phosphate ester hydrolysis promoted by lanthanide (III) and transition metal complexes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0015/NQ55393.pdf.
Повний текст джерелаWilliams, Daniel M. "Phosphate ester hydrolysis promoted by lanthanide (III) and transition metal complexes." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35551.
Повний текст джерелаIn principle, simple dinuclear metal complexes could hydrolyze phosphate esters by double Lewis acid activation or by a combination of single Lewis acid activation and metal-hydroxide activation. These two mechanisms are kinetically indistinguishable. In this study, two different phosphate substrates are used to distinguish these mechanisms.
Lanthanide (iii) salts have proven extraordinarily effective in accelerating the rate of phosphate ester hydrolysis by several orders of magnitude. Consequently, there has been much effort in recent years to develop a ligand that would bind lanthanides so as to further improve their ability to hydrolyze phosphates. These efforts have met with limited success. Reported here is a dinuclear lanthanide (iii) complex which hydrolyzes BNPP (bis p-nitrophenyl phosphate) with unprecedented reactivity at pH 7.0 and 25°C.
A mononuclear copper (ii) 6,6'-diamino-2,2 '-bipyridyl complex is synthesized which gives one of the fastest rate accelerations reported for hydrolyzing 2',3 '-cAMP. A hydrogen bonding mechanism is proposed for the acceleration of the rate of hydrolysis of the cyclic phosphate.
Lindner, N. M. "Affinity purification and use of alkaline phosphatase for phosphate ester synthesis." Thesis, Open University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234750.
Повний текст джерелаDudaczek, Jürgen. "Oktapeptide als neue Organokatalysatoren zur Hydrolyse von Phosphaten und Estern." kostenfrei, 2009. http://www.opus-bayern.de/uni-wuerzburg/volltexte/2009/3517/.
Повний текст джерелаEberhardt, Luc. "New chiral amino-phosphanes : Applications in asymmetric hydrogenation of alpha-dehydroamino acid esters." Université Louis Pasteur (Strasbourg) (1971-2008), 2007. http://www.theses.fr/2007STR13081.
Повний текст джерелаThis thesis is devoted to the synthesis of new chiral phosphorus ligands and their study in the homogeneous catalytic asymmetric hydrogenation of cinnamic acid methyl ester derivatives. These aminophosphanes and phosphoramidites behave either as monodentate P(III) ligands when they are derived from amino acids or from dinaphtho[2,1-d:1',2'-f][1,3,2]dihydroazepine, or as P(III) chelating ligands when they are derived from hydrazines. The study of their metal-complexes showed that these compounds are able to coordinate d8 metal ions such as rhodium(I) or platinum(II). The catalytic properties of the abovementioned ligands as regards asymmetric olefin hydrogenation can be summarized as follows: 1) the enantiomeric excess is highly dependant on the nature of the asymmetric fragment substituting the phosphorus atom, in this case the 1,1'-binaphthalene-2,2'-diyl group; 2) the use of a chiral dinaphtho[2,1-d:1',2'-f][1,3,2]dihydroazepino substituent results in higher enantiomeric excesses compared to phosphoramidite ligands containing an achiral amino group
Mdhlovu, Johan. "Optimisation of water-in-oil microemulsion formulation stabilised by nonylphenol ethoxylated phosphate ester." Diss., Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-03062006-093400.
Повний текст джерелаÅström, Hans. "Studies on phosphate ester cleavage and development of oligonucleotide based artificial nucleases (OBAN's) /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-935-8/.
Повний текст джерелаTarico, Daniel Joseph 1965. "Dispersion of alumina powder in secondary butyl alcohol with a phosphate ester surfactant." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277307.
Повний текст джерелаMyrex, Ronald Dustan. "Synthesis and characterization of phosphorus-containing inorganic polymers." Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2007r/myrex.pdf.
Повний текст джерелаAdditional advisors: Houston Boyd, Tracy Hamilton, Christopher Lawson, Charles Watkins. Description based on contents viewed Feb. 8, 2008; title from title screen. Includes bibliographical references.
Machairas, Alexandros 1980. "The UV/H2O2 advanced oxidation process in UV disinfection units : removal of selected phosphate esters by hydroxyl radical." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/29410.
Повний текст джерелаIncludes bibliographical references (leaves 96-97).
In this work, the issue of how to remove phosphate esters from drinking water is examined. From the various treatment processes available, the oxidation of phosphate esters through hydroxyl radical generated by the UV/H202 process applied at a UV disinfection unit was selected for evaluation. The second-order rate constants of the reactions of two phosphate esters, Tri(2-butoxyethyl) phosphate (TBEP) and Tri-2-chloroethyl phosphate (TCEP) , with hydroxyl radical were estimated from our experimental data to be 2.1000 M-1s-1 and 2 109 M-is-1 respectively A comprehensive kinetic model of the oxidation process was derived. Finally computer simulations were used to exhibit the potential of this treatment process and to examine the effects of pH, total carbonate species concentration, initial hydrogen peroxide dose, and light intensity on its efficiency. The results are not very encouraging when a UV unit designed for disinfection is used. For typical values of pH and total carbonate species (pH=8 and CT=5' 10-4 M) the 1 s order rate coefficients for removal of the phosphate esters are 6.3 10-4 (s-1) for TBEP and 6.3 10-5 (s-1) for TCEP. If higher light intensity is applied in the reactor (50 times higher), and initial hydrogen peroxide dose of 10-3 M and CT remains 5 10-4 M, the 1st order reaction rate coefficients become 2.9 10-2 (s-1) and 2.9-10-3 (s-1) for TBEP and TCEP respectively.
by Alexandros Machairas.
M.Eng.
Lambert, Emilie. "Préparation de phosphinates difluorés, isostères des diesters de phosphate. Application à la synthèse de dinucléotides modifiés." Rouen, 2013. http://www.theses.fr/2013ROUES040.
Повний текст джерелаAntisense strategy and small interfering RNAs use modified oligonucleotides (MONs) which specifically recognize and bind ti mRNA strands to modulate genes expressions. To enhance oligonucleotide drug properties, one important strategy is the replacement of the phosphate group by isosters. This PhD work aimed at developing a strategy to obtain a new, essentially non-hydrolysable difluorophosphinyle unit, to replace the diesterified phosphate group. First, a methodology involving thionylated analogues was developed on model substrate. These hitherto unreported compounds are more stable under alkylation conditions. Conversion of phosphinothioyle group delivered successfully the desired difluorophosphinates. The requisite furanosyles units were prepared and the above strategy was applied to generate a fully protected 3,5-bisfuranosyl difluorinated phosphinate. Stereocontroled glycosylation with thymine reactant led to the dinucleotide analogue. Calculation studies highlighted the isosteric potential of difluorophosphinate linkage, as new analogue of diesterified phoshate group
Conibear, Anne Claire. "Synthesis and evaluation of novel inhibitors of 1-Deoxy-D-xylolose-5-phosphate reductoisomerase as potential antimalarials." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1008282.
Повний текст джерелаKMBT_363
Adobe Acrobat 9.54 Paper Capture Plug-in
Lopes, Shailesh M. "Synthesis, characterization and applications of fats and oil derived phase change materials." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5938.
Повний текст джерелаThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on March 20, 2009) Vita. Includes bibliographical references.
Eriksson, Ulrika. "Contribution of polyfluoroalkyl phosphate esters (PAPs) and other precursor compounds to perfluoroalkyl carboxylates (PFCAs) in humans and the environment." Doctoral thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-52010.
Повний текст джерелаJubian, Vrej. "Relationship between ligand structure and reactivity for copper (II) complex mediated hydrolysis of phosphate diesters, carboxylic esters, and amides." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74656.
Повний текст джерелаThe complex (Cu(2,2$ sp prime$-dipyridylamine)(OH$ sb2$)$ sb2$) $ sp{2+}$ efficiently catalyzes the hydrolysis of carboxylic esters (4-nitrophenyl acetate, methyl trifluoroacetate, and methyl acetate). Methyl acetate, when bound to the copper complex, is hydrolyzed at a rate that is comparable to the k$ sb{ rm cat}$ values for chymotrypsin catalyzed hydrolyses of esters. The hydrolysis of N,N-dimethylformamide by (Cu(2,2$ sp prime$-dipyridylamine)(OH$ sb2$)$ sb2$) $ sp{2+}$ at neutral pH, 100$ sp circ$C, proceeds at least two hundred times faster than that by (Cu(2,2$ sp prime{:}6 sp prime,2 sp{ prime prime}$-terpyridine)(OH$ sb2 ) rbrack sp{2+}.$ A detailed mechanism of the reaction has been given to explain the structural requirements of a metal catalyst necessary for hydrolyzing esters and amides, and a mechanism for Carboxypeptidase A catalyzed hydrolysis of peptides has been proposed.
Seifert, Gabrielle Victoria. "Amorphous Calcium Phosphate Composites of a Phenylalanine-based Poly(ester urea) Poly(1-PHE-6)." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1460388339.
Повний текст джерелаLe, Guevel Eric. "Substitution nucléophile de composés organophosphorés par les ions oximate : application en décontamination douce." Versailles-St Quentin en Yvelines, 1997. http://www.theses.fr/1997VERS0017.
Повний текст джерелаCampagne-Mina, Jean-Marc. "Synthèse de phosphino et phosphonopeptides haptènes pour la production d'abaymes à activité protéolytique." Montpellier 2, 1994. http://www.theses.fr/1994MON20254.
Повний текст джерелаIssenhuth, Jean-Thomas. "Catalyse énantiosélective et polymérisation : Etude de la réactivité de complexes de cuivre et d'aluminium." Université Louis Pasteur (Strasbourg) (1971-2008), 2008. https://publication-theses.unistra.fr/public/theses_doctorat/2008/ISSENHUTH_Jean-Thomas_2008.pdf.
Повний текст джерелаBaudouin, Jacky. "Synthèse et réactions sélectives d' α oxoesters β fonctionnels et de leurs dérivés : nouveaux synthons et réactifs dans les séries du phosphore, du soufre et de l'azote". Rouen, 1987. http://www.theses.fr/1987ROUE5050.
Повний текст джерелаChung, Yongseong. "Diene substituent effects on the retro Diels-Adler reaction and dimeric Co(III) complex promoted phosphate ester hydrolysis /." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487671108308264.
Повний текст джерелаCoulombeau, Agnès. "Synthèse de phosphinodipeptides." Montpellier 2, 2000. http://www.theses.fr/2000MON20147.
Повний текст джерелаSang, Yijun. "Cross-linked resistant starch from high-amylose corn starch, and structures of phosphate esters in cross-linked resistant wheat starch determined by ³¹P NMR spectroscopy /." Search for this dissertation online, 2004. http://wwwlib.umi.com/cr/ksu/main.
Повний текст джерелаPRADINES, ANTOINE. "Phosphorylation enzymatique de polyols par la phosphatase alcaline optimisation de la synthese de glycerol-1-phosphate." Toulouse 3, 1989. http://www.theses.fr/1989TOU30015.
Повний текст джерелаSadik, Mourad. "Étude ultramicroélectrochimique des esters phosphoriques comme solvant : application a la détermination de l'indice d'acide des lubrifiants par amperométrie à une ultramicroélectrode de platine." Nancy 1, 1992. http://www.theses.fr/1992NAN10245.
Повний текст джерелаBorges, Larissa Braga Bueno. "Aplicação de catalisador químico heterogêneo na transesterificação de miscelas etanólicas de óleo de soja." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-10112014-113518/.
Повний текст джерелаLarge scale biodiesel production motivates research and development of cleaner low cost technologies related to the manufacture and quality control of this fuel. The extraction of soybean oil with the solvent ethanol results in the production of a rich in oil semi-refined miscella that can be directly esterified to produce ethyl esters, without the need of solvent evaporation. The transesterification of micellae by heterogeneous catalysis can add the benefits of reusing the catalyst. The aim of this work was to promote optimization of the transesterification of ethanolic soybean oil miscellae under heterogeneous catalysis of tripotassium phosphate (K3PO4), analyze the yield of reaction with reused catalyst and promote its regeneration. A technique for quantification of the ester content involving separation with thin layer chromatography and color analysis by spectrophotometry was also performed. Biodiesel samples of known ester content were oxidized by the potassium dichromate in sulfuric acid, and the change in color of the reagent from orange to green was quantified. The acid dichromate was able to completely oxidize the isolated fraction esters, correctly determining their content with a maximum variation of 2.05%, and revealing a fixed relation of 0,08?g of dichromate consumed per ?g of biodiesel. The transesterification with K3PO4 was optimized, reaching yields of 96.4% under the conditions of 1:12 molar ratio, 5% catalyst and 400rpm stirring in 100 minutes of reaction. The use of K3PO4 does not require preparation steps, but showed evidence of solubility in the reaction medium. Yields obtained with reused catalyst were low for all treatments, being the moderate washing (LM) chosen due to lower variability of mass recovered after reuses. The regenerated catalyst resulted in yields of 58.72%, equivalent to 84% of that obtained with fresh catalyst. The K3PO4 had its activity impaired by saponification and emulsification phenomena, requiring changes to make its reuse feasible. The use of heterogeneous catalysts with ethanolic rich in oil miscellae has the potential to reduce production costs due to the production of vegetable oil without the need of refining and the reuse of solid catalyst.
Roux, Philippe. "Rôle de l'estérase neurotoxique dans les polyneuropathies rétardées induites par les organo-phosphores." Paris 5, 1994. http://www.theses.fr/1994PA05P235.
Повний текст джерелаLakhrissi, Mohammed. "Dichloromethylenation de lactones et d'esters : synthèse et réactivité." Nancy 1, 1993. http://www.theses.fr/1993NAN10176.
Повний текст джерелаChan, Wing-sum. "Resonance Raman, time-resolved resonance Raman and density functional theory study of Benzoin diethyl phosphate, selected P-Hydroxy and P-methoxy substituted phenacyl ester phototrigger and model compounds." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B36198821.
Повний текст джерелаChan, Wing-sum, and 陳穎心. "Resonance Raman, time-resolved resonance Raman and density functional theory study of Benzoin diethyl phosphate, selected P-Hydroxy and P-methoxy substituted phenacyl ester phototrigger and model compounds." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B36198821.
Повний текст джерелаGoumain, Sophie. "Application de l'activation électrochimique du magnésium à l'électrosynthèse d'alcènes chlorés et de cyclopropylphosphonates fonctionnels : perspectives et limitations." Rouen, 1999. http://www.theses.fr/1999ROUES065.
Повний текст джерелаMilde, Bianca. "(Ethynyl-)Ferrocenyl Phosphine Palladium Complexes and (Bis-)Phosphinoimidazol(e/ium) Compounds and their Application in Homogeneous Catalysis." Doctoral thesis, Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-90521.
Повний текст джерела