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[en] An efficient green route for monoacylation of aromatic diamines, namely o-phenylenediamine and p-phenylenediamine and aliphatic diamines ethylenediamine and piperazine using N-acylbenzotriazoles (NABs) in n-butanol was developed. The new protocol does not require prior selective protection of the diamine and comprises simple conditions, short reaction times, an easy work up as well as high isolated yields (69–94%). Moreover, the method described herein enable stepwise acylation of aliphatic diamines such as ethylenediamine and piperazine with two different N-acylbenzotriazoles affording unsymmetrical substituted diamines that can be used for construction of pharmaceutically important targets such as drugs, foldamers, and drug conjugates. Graphic abstract:
[en] In this paper, polymer composite membranes and ceramic composite membranes were prepared in order to compare differences in pervaporation performances relative to the support layers. PVDF was used for the polymer support layers, and a-Al2O3 was used for the ceramic support layers. For active layer was coated for PDMS, which is a rubbery polymer. The characterization of membranes were analysed by SEM, contact angle, and XPS. We studied performances relative to the composite membrane support layers in the ABE mixture solutions. The results of the pervaporation, the flux of the ceramic composite membrane was shown to be 250.87 g/m2h, which was higher than that of polymer composite membranes, at 195.64 g/m2h. However, it was determined that the separation factor of the polymer composite membranes was 31.98 which were higher than that of the ceramic composite membranes, at 20.66
[en] This paper describes the results of experiments by the writers with radioinitiation of chain branched reactions of the oxidation of organic compounds. The function of radiation as an initiating agent is described with reference to the oxidation of several unsaturated hydrocarbons and butanol. The reaction is self-accelerating and proceeds spontaneously after radiation has ceased. A detailed investigation was made of a process from oxidizing benzene, which has a high radiation resistance. The writers devised a method of sensitizing the radioinitiation of the oxidation of radiation-resistant substances by chemically inert but non-radiation-resistant substances. The main quantitative features of the process for the radiooxidation of benzene are stated to be the accumulation of various reaction products, and the effect of temperature, pressure, power and radiation dosage on the process of such accumulation. Information was obtained about the mechanism of the process. The design of circulating equipment is described. (author)
[fr]Dans ce memoire, les auteurs presentent les resultats d'une etude consacree a l'amorcage sous rayonnement de reactions, d'oxydation des composes organiques, par ramification en chaine. Ils montrent le role des rayonnements en tant qu'agents d'amorcage de la reaction, en citant comme exemples l'oxydation de certains hydrocarbures non satures et du butanol. La reaction possede un caractere d'auto-acceleration et continue spontanement lorsque l'action des rayonnements a cesse. La reaction d'oxydation du benzene a ete etudiee en detail; elle est caracterisee par la haute stabilite de la substance vis-a-vis de l'action des rayonnements. Les auteurs formulent les principes de la sensibilisation, par l'action de substances instables vis-a-vis des rayonnements de l'amorcage sous rayonnement de la reaction d'oxydation de substances stables vis-a-vis des rayonnements et chimiquement inertes. Le memoire fournit les caracteristiques quantitatives fondamentales de la reaction d'oxydation par radiolyse du benzene : accumulation des divers produits de la reaction, action de la temperature, de la pression, de la puissance et de la dose d'irradiation sur le processus d'accumulation des produits de la reaction. Quelques conclusions sont exposees sur le mecanisme de la reaction. Les auteurs decrivent la construction de l'installation qui fonctionne en circuit ferme. (author)
[es]Figuran en esta memoria los resultados de los trabajos efectuados por los autores sobre la radioiniciacion de las reacciones de oxidacion de compuestos organicos en cadenas ramificadas. Se demuestra el papel que desempenan las radiaciones como agente de iniciacion, tomando como ejemplo la oxidacion del butanol y de varios hidrocarburos no saturados. La reaccion tiene caracter autoacelerador y prosigue espontaneamente al cesar la irradiacion. Se ha estudiado detalladamente el proceso de oxidacion del benceno, compuesto que se caracteriza por una elevada resistencia a las radiaciones. Los autores han ideado un metodo para sensibilizar la radioiniciacion de la oxidacion de compuestos radioresistentes por sustancias quimicamente inertes, pero inestables frente a las radiaciones. En la memoria se examinan los principales factores de que depende la radiooxidacion del benceno, a saber, concentracion de los distintos productos de reaccion e influencia de la temperatura, de la presion, de la energia y de la dosis de radiacion en el proceso de acumulacion de esos productos. Los autores formulan tambien algunas conclusiones sobre el mecanismo del proceso y describen la construccion de la instalacion de circulacion. (author)
[ru]V doklade predstavleny rezul'taty issledovanij avtorov po radiatsionnomu initsiirovaniyu tsepnykh razvetvlennykh reaktsij okisleniya organicheskikh soedinenij. Na primere okisleniya nekotorykh nenasyshchennykh uglevodorodov i butanola pokazana rol' izlucheniya kak initsiiruyushchego agenta. Reaktsiya imeet avtouskoryayushchijsya kharakter i idet samoproizvol'no posle prekrashcheniya dejstviya izlucheniya. Podrobno issledovan protsess okisleniya benzola, dlya kotorogo kharakterna povyshennaya ustojchivost' k dejstviyu izlucheniya. Avtory sformulirovali printsip sensibilizatsii radiatsionnogo initsiirovaniya protsessa okisleniya radiatsionno-stojkikh veshchestv khimicheski inertnymi, radiatsionno-nestojkimi veshchestvami. Privedeny osnovnye kolichestvennye kharakteristiki protsessa radio liticheskogo okisleniya benzola : nakoplenie razlichnykh produktov reaktsii, vliyanie temperatury, davleniya, moshchnosti i dozy izlucheniya na protsess nakopleniya produktov reaktsii. Sdelany nekotorye vyvody o mekhanizme protsessa. Privedena konstruktsiya ustanovki, rabotayushchaya po tsirkulyatsionnomu sposobu. (author)
[en] Full text: A probabale stage by stage scheme of mechanism of the reaction of vapor phase dehydration of butanol-2 and pentanol-2 at the zeolite catalyst NaY with due regard of isomer composition of olefmic has been suggested. Theoretically grounded kinetic model of the process has been worked up and the values of its kinetic parameters determined
[en] The JLab CLAS g9a/FROST experiments are double polarization measurements that have accumulated photo-production data using linearly polarized, tagged photons incident on a longitudinally polarized, frozen spin butanol target. The analysis of the resulting coherent peaks was used to determine the photon polarization, which is in agreement with phenomenological calculations.
[en] Transforming renewable biomass into cost competitive high-performance biofuels and bioproducts is key to US energy security. Butanol production by microbial fermentation and chemical conversion to polyolefins, elastomers, drop-in jet or diesel fuel, and other chemicals is a promising solution. A high temperature fermentation process can facilitate butanol recovery up to 40%, by using gas stripping. Other benefits of fermentation at high temperatures are optimal hydrolysis rates in the saccharification of biomass which leads to maximized butanol production, decrease in energy costs associated with reactor cooling and capital cost associated with reactor design, and a decrease in contamination and cost for maintaining a sterile environment. Butanol stripping at elevated temperatures gives higher butanol production through constant removal and continuous fermentation. We describe methods used in an attempt to genetically prepare Geobacillus caldoxylosiliticus for insertion of a butanol pathway. Methods used were electroporation of electrocompetent cells, ternary conjugation with E. coli, and protoplast fusion.
[en] Highlights: • Process design of a separation section in an ethanol-to-butanol process performed. • Separation costs are estimated to be 7.9–10.6 MJ/kg n-butanol. • Energy consumption affected by splitter column influent composition. • Energy consumption affected by catalyst ability to use aqueous ethanol. - Abstract: A complete separation scheme has been designed for the effluent of a high-pressure ethanol-to-butanol catalytic reactor, producing 250,000 tonnes of n-butanol per year. The effluent contains water, hydrogen and a diverse range of C2-C4 oxygenates: unconverted ethanol, n-butanol, acetaldehyde, ethyl acetate, and acetal. Fundamental phase equilibrium relationships suggested use of conventional, extractive, and heterogeneous azeotropic distillation units to perform the separations. All reactor effluent species exit the separation process at mole purities of at least 99%. Separation costs are estimated to range from 9.0 to 10.6 MJ/kg n-butanol, which is comparable with the separation costs of n-butanol obtained from established acetone-butanol-ethanol (ABE) separation process.
[en] Highlights: • The VLE of 1-(methoxymethoxy)-2-methyl-propane binary systems were reported. • Saturated vapor pressure data of 1-(methoxymethoxy)-2-methyl-propane were reported. • The VLE data provide a reference for separating 1-(methoxymethoxy)-2-methyl-propane. - Abstract: Isobaric vapour-liquid equilibria (VLE) experimental results for binary systems of 1-(methoxymethoxy)-2-methyl-propane with 1-butanol and isobutanol at 101.33 kPa were determined. Each binary mixture shows a minimum boiling azeotrope at 101.33 kPa, in which the azeotropic temperature and composition are 381.19 K and 26.72 mol% (1-butanol) and 377.55 K and 53.34 mol% (isobutanol), respectively. The VLE measurements were correlated by the van Laar, Wilson and NRTL models for which the binary interaction parameters are reported. The results show that the measurements of two binary systems provide a good agreement with the calculated values acquired by the Wilson and NRTL models, respectively. The thermodynamic consistency of the VLE measurements was checked using the traditional area test and the direct test methods.
[en] The Argonne picosecond pulse radiolysis system and its application towards understanding solvation processes in polar liquids are described. The alcohols studied are n-butanol, 2-decanol, and t-butanol
[en] Highlights: → The (liquid + liquid) equilibrium of hyperbranched polyester solutions is calculated. → The solvents are n-alkanes, propan-1-ol, and butan-1-ol. → The lattice-cluster theory is combined with a chemical association model. → The solvent molecules are assumed to be linear chains of segments. → The calculations agree reasonably well with the experimental data. - Abstract: The (liquid + liquid) equilibrium of solutions of hyperbranched polyesters is calculated with the lattice-cluster theory (LCT) combined with a chemical association model. The considered solvents are n-alkanes as well as propan-1-ol and butan-1-ol. The structure of the solvents is also considered in the framework of the LCT, assuming the solvent molecules as linear chains of several segments. For polymer solutions with the non-associating n-alkanes only the self association of the hyperbranched polymer molecules has to be considered by the chemical association lattice model (CALM). For the solutions of the type alcohol + hyperbranched polymer additionally the cross association is taken into account by a modified version of the extended chemical association lattice model (ECALM). The association effects are proved to influence strongly the phase equilibrium. Calculating the cloud-point curve and the critical point the polydispersity of the polymer samples is neglected. There is a reasonable agreement of the calculated curves with the experimental data taken from the literature.