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Yoshimori Miyano - One of the best experts on this subject based on the ideXlab platform.
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henry s law constants and infinite dilution activity coefficients of propane propene butane 2 methylpropane 1 butene 2 methylpropene trans 2 butene cis 2 butene 1 3 butadiene dimethylether chloroethane 1 1 difluoroethane and hexane in tetrahydropyran
Journal of Chemical & Engineering Data, 2007Co-Authors: Yoshimori Miyano, Sigemichi Uno, Katsumi Tochigi, Satoru Kato, Hiroshi YasudaAbstract:Henry's law constants and infinite dilution activity coefficients of propane, propene, butane, 2-methylpropane, 1-butene, 2-methylpropene, trans-2-butene, cis-2-butene, 1,3-butadiene, dimethylether, chloroethane, 1,1-difluoroethane, and hexane in tetrahydropyran in the temperature range of (250 to 330) K were measured by a gas stripping method, and partial molar excess enthalpies and entropies were evaluated from the activity coefficients. A rigorous formula for evaluating the Henry's law constants from the gas stripping measurements was used for these highly volatile mixtures. The estimated uncertainties are about 2 % for the Henry's law constants and 3 % for the infinite dilution activity coefficients. The Henry's law constants followed the order of the increasing Henry's law constant with decreases in the normal boiling point temperature of the solutes except for polar solutes. The partial molar excess entropies and enthalpies of the solutes at infinite dilution in tetrahydropyran are smaller than thos...
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henry s constants and infinite dilution activity coefficients of propane propene butane isobutane 1 butene isobutene trans 2 butene and 1 3 butadiene in 2 propanol at 250 330 k
Journal of Chemical & Engineering Data, 2004Co-Authors: Yoshimori MiyanoAbstract:The Henry's constants and the infinite dilution activity coefficients of propane, propene, butane, isobutane, 1-butene, isobutene, trans-2-butene, and 1,3-butadiene in 2-propanol in the temperature range 250 K to 330 K are measured by a gas stripping method. The rigorous formula for evaluating the Henry's constants from the gas stripping measurements is used for these highly volatile mixtures. The accuracy of the measurements is about 2% for Henry's constants and 3% for the estimated infinite dilution activity coefficients. In the evaluations for the infinite dilution activity coefficients, the nonideality of the solute is not negligible, especially at higher temperatures, and the activity coefficients include the estimation uncertainty of about 1%.
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henry s constants and infinite dilution activity coefficients of propane propene butane isobutene 1 butene isobutane trans 2 butene and 1 3 butadiene in 1 propanol at t 260 to 340 k
The Journal of Chemical Thermodynamics, 2004Co-Authors: Yoshimori MiyanoAbstract:Abstract The Henry’s constants and the infinite dilution activity coefficients of propane, propene, butane, isobutane, 1-butene, isobutene, trans-2-butene and 1,3-butadiene in 1-propanol at T=(260 to 340) K are measured by a gas stripping method. The rigorous formula for evaluating the Henry’s constants from the gas stripping measurements is used for these highly volatile mixtures. The accuracy of the measurements is about 2% for Henry’s constants and 3% for the estimated infinite dilution activity coefficients. In the evaluations for the infinite dilution activity coefficients, the nonideality of solute is not negligible especially at higher temperatures and the estimated uncertainty in the infinite dilution activity coefficients include 1% for nonideality.
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henry s constants of butane isobutane 1 butene and isobutene in methanol at 255 320 k
Fluid Phase Equilibria, 2003Co-Authors: Yoshimori Miyano, Koichiro Nakanishi, Kenji FukuchiAbstract:Abstract The Henry’s constants and the infinite dilution activity coefficients of butane, isobutane, 1-butene and isobutene in methanol at 255–320 K are measured by a gas stripping method. The rigorous formula for evaluating the Henry’s constants from the gas stripping measurements is proposed for these highly volatile mixtures. By using this formula, a volume effect of vapor phase and the effect of nonideality of fluids are discussed. In the evaluations for activity coefficients the nonideality of solute was not negligible especially at higher temperatures. The values of Henry’s constants of butane are much different from those of isobutane, while the activity coefficients are not so different to each other. The activity coefficients of butane are about 2.5% greater than those of isobutane, and those of 1-butene are about 4% greater than those of isobutene.
Kevin R Wilson - One of the best experts on this subject based on the ideXlab platform.
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reaction rate and isomer specific product branching ratios of c2h c4h8 1 butene cis 2 butene trans 2 butene and isobutene at 79 k
Journal of Physical Chemistry A, 2013Co-Authors: J Bouwman, Martin Fournier, Ian R Sims, Stephen R Leone, Kevin R WilsonAbstract:The reactions of C2H radicals with C4H8 isomers 1-butene, cis-2-butene, trans-2-butene, and isobutene are studied by laser photolysis-vacuum ultraviolet mass spectrometry in a Laval nozzle expansion at 79 K. Bimolecular-reaction rate constants are obtained by measuring the formation rate of the reaction product species as a function of the reactant density under pseudo-first-order conditions. The rate constants are (1.9 ± 0.5) × 10(-10), (1.7 ± 0.5) × 10(-10), (2.1 ± 0.7) × 10(-10), and (1.8 ± 0.9) × 10(-10) cm(3) s(-1) for the reaction of C2H with 1-butene, cis-2-butene, trans-2-butene, and isobutene, respectively. Bimolecular rate constants for 1-butene and isobutene compare well to values measured previously at 103 K using C2H chemiluminescence. Photoionization spectra of the reaction products are measured and fitted to ionization spectra of the contributing isomers. In conjunction with absolute-ionization cross sections, these fits provide isomer-resolved product branching fractions. The reaction between C2H and 1-butene yields (65 ± 10)% C4H4 in the form of vinylacetylene and (35 ± 10)% C5H6 in the form of 4-penten-1-yne. The cis-2-butene and trans-2-butene reactions yield solely 3-penten-1-yne, and no discrimination is made between cis- and trans-3-penten-1-yne. Last, the isobutene reaction yields (26 ± 15)% 3-penten-1-yne, (35 ± 15)% 2-methyl-1-buten-3-yne, and (39 ± 15)% 4-methyl-3-penten-1-yne. The branching fractions reported for the C2H and butene reactions indicate that these reactions preferentially proceed via CH3 or C2H3 elimination rather than H-atom elimination. Within the experimental uncertainties, no evidence is found for the formation of cyclic species.
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reaction rate and isomer specific product branching ratios of c2h c4h8 1 butene cis 2 butene trans 2 butene and isobutene at 79 k
Journal of Physical Chemistry A, 2013Co-Authors: J Bouwman, Martin Fournier, Ian R Sims, S Leone, Kevin R WilsonAbstract:The reactions of C2H radicals with C4H8 isomers 1-butene, cis-2-butene, trans-2-butene, and isobutene are studied by laser photolysis-vacuum ultraviolet mass spectrometry in a Laval nozzle expansion at 79 K. Bimolecular-reaction rate constants are obtained by measuring the formation rate of the reaction product species as a function of the reactant density under pseudo-first-order conditions. The rate constants are (1.9 ± 0.5) × 10–10, (1.7 ± 0.5) × 10–10, (2.1 ± 0.7) × 10–10, and (1.8 ± 0.9) × 10–10 cm3 s–1 for the reaction of C2H with 1-butene, cis-2-butene, trans-2-butene, and isobutene, respectively. Bimolecular rate constants for 1-butene and isobutene compare well to values measured previously at 103 K using C2H chemiluminescence. Photoionization spectra of the reaction products are measured and fitted to ionization spectra of the contributing isomers. In conjunction with absolute-ionization cross sections, these fits provide isomer-resolved product branching fractions. The reaction between C2H and ...
J Bouwman - One of the best experts on this subject based on the ideXlab platform.
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reaction rate and isomer specific product branching ratios of c2h c4h8 1 butene cis 2 butene trans 2 butene and isobutene at 79 k
Journal of Physical Chemistry A, 2013Co-Authors: J Bouwman, Martin Fournier, Ian R Sims, Stephen R Leone, Kevin R WilsonAbstract:The reactions of C2H radicals with C4H8 isomers 1-butene, cis-2-butene, trans-2-butene, and isobutene are studied by laser photolysis-vacuum ultraviolet mass spectrometry in a Laval nozzle expansion at 79 K. Bimolecular-reaction rate constants are obtained by measuring the formation rate of the reaction product species as a function of the reactant density under pseudo-first-order conditions. The rate constants are (1.9 ± 0.5) × 10(-10), (1.7 ± 0.5) × 10(-10), (2.1 ± 0.7) × 10(-10), and (1.8 ± 0.9) × 10(-10) cm(3) s(-1) for the reaction of C2H with 1-butene, cis-2-butene, trans-2-butene, and isobutene, respectively. Bimolecular rate constants for 1-butene and isobutene compare well to values measured previously at 103 K using C2H chemiluminescence. Photoionization spectra of the reaction products are measured and fitted to ionization spectra of the contributing isomers. In conjunction with absolute-ionization cross sections, these fits provide isomer-resolved product branching fractions. The reaction between C2H and 1-butene yields (65 ± 10)% C4H4 in the form of vinylacetylene and (35 ± 10)% C5H6 in the form of 4-penten-1-yne. The cis-2-butene and trans-2-butene reactions yield solely 3-penten-1-yne, and no discrimination is made between cis- and trans-3-penten-1-yne. Last, the isobutene reaction yields (26 ± 15)% 3-penten-1-yne, (35 ± 15)% 2-methyl-1-buten-3-yne, and (39 ± 15)% 4-methyl-3-penten-1-yne. The branching fractions reported for the C2H and butene reactions indicate that these reactions preferentially proceed via CH3 or C2H3 elimination rather than H-atom elimination. Within the experimental uncertainties, no evidence is found for the formation of cyclic species.
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reaction rate and isomer specific product branching ratios of c2h c4h8 1 butene cis 2 butene trans 2 butene and isobutene at 79 k
Journal of Physical Chemistry A, 2013Co-Authors: J Bouwman, Martin Fournier, Ian R Sims, S Leone, Kevin R WilsonAbstract:The reactions of C2H radicals with C4H8 isomers 1-butene, cis-2-butene, trans-2-butene, and isobutene are studied by laser photolysis-vacuum ultraviolet mass spectrometry in a Laval nozzle expansion at 79 K. Bimolecular-reaction rate constants are obtained by measuring the formation rate of the reaction product species as a function of the reactant density under pseudo-first-order conditions. The rate constants are (1.9 ± 0.5) × 10–10, (1.7 ± 0.5) × 10–10, (2.1 ± 0.7) × 10–10, and (1.8 ± 0.9) × 10–10 cm3 s–1 for the reaction of C2H with 1-butene, cis-2-butene, trans-2-butene, and isobutene, respectively. Bimolecular rate constants for 1-butene and isobutene compare well to values measured previously at 103 K using C2H chemiluminescence. Photoionization spectra of the reaction products are measured and fitted to ionization spectra of the contributing isomers. In conjunction with absolute-ionization cross sections, these fits provide isomer-resolved product branching fractions. The reaction between C2H and ...
Chihhao Chin - One of the best experts on this subject based on the ideXlab platform.
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comparison of two body and three body decomposition of ethanedial propanal propenal n butane 1 butene and 1 3 butadiene
Journal of Chemical Physics, 2012Co-Authors: Chihhao ChinAbstract:We investigated two-body (binary) and three-body (triple) dissociations of ethanedial, propanal, propenal, n-butane, 1-butene, and 1,3-butadiene on the ground potential-energy surfaces using quantum-chemical and Rice-Ramsperger-Kassel-Marcus calculations; most attention is paid on the triple dissociation mechanisms. The triple dissociation includes elimination of a hydrogen molecule from a combination of two separate terminal hydrogen atoms; meanwhile, the rest part simultaneously decomposes to two stable fragments, e.g., C2H4, C2H2, or CO. Transition structures corresponding to the concerted triple dissociation were identified using the B3LYP/6-311G(d,p) level of theory and total energies were computed using the method CCSD(T)/6-311+G(3df, 2p). The forward barrier height of triple dissociation has a trend of ethanedial < propanal < propenal < n-butane < 1-butene < 1,3-butadiene, pertaining to the reaction enthalpy. Ratios of translational energies of three separate fragments could be estimated from the t...
Daniel J Arp - One of the best experts on this subject based on the ideXlab platform.
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two distinct alcohol dehydrogenases participate in butane metabolism by pseudomonas butanovora
Journal of Bacteriology, 2002Co-Authors: Alisa S Vangnai, Daniel J Arp, Luis A SayavedrasotoAbstract:Pseudomonas butanovora (ATCC 43655) is an aerobic gram-negative proteobacterium closely related to the genera Thauera and Azoarcus as shown by analysis of its 16S rRNA (1). This organism has been classified in the genus Pseudomonas based on its morphology, physiology, and biochemistry (39, 40). P. butanovora was isolated from activated sludge from an oil-refining company for the purpose of generating biomass from n-alkanes (39, 40). P. butanovora can derive energy for growth from C2 to C9 n-alkanes and any of their oxidation products as well as from a variety of other carbon sources (39, 40). Butane-grown P. butanovora can oxidize some chlorinated hydrocarbons by cometabolism through the action of a monooxygenase (18) and thus may have applications in bioremediation schemes. The pathway for the oxidation of butane in P. butanovora proceeds primarily from butane to 1-butanol, to butyraldehyde, to butyrate (2), and then probably to the β-oxidation pathway of fatty acid oxidation. As in other alkane utilizers (3, 27, 36), in P. butanovora the oxidation of the alkane (butane) is initiated by the action of a monooxygenase (19). Each intermediate in the pathway accumulated in the presence of appropriate inhibitors, supported cell growth, and stimulated O2 consumption (2). The presence of a terminal butane oxidation pathway (i.e., production of 1-butanol) in P. butanovora was indicated (2). Although butane-grown cells consumed 2-butanol, 2-butanol production (indicative of a subterminal oxidation pathway) was not demonstrated, even in the presence of appropriate inhibitors of 2-butanol consumption. For P. butanovora four different alcohol dehydrogenases (ADHs) with different specificities towards primary and secondary alcohols were identified on native gels stained for activity (45). Among these ADHs, 1-butanol dehydrogenase (BDH) was characterized biochemically (45). BDH enzyme activity was detected in butane- and 1-butanol-grown cells but not lactate-grown cells. BDH is a soluble, periplasmic, type II NAD+-independent quinohemoprotein that contains 1.0 mol of pyrroloquinoline quinone (PQQ) and 0.25 mol of ratio heme c as prosthetic groups and exists as a monomer with an apparent molecular mass of 67 kDa (45). The liquid-alkane metabolisms of other gram-negative proteobacteria such as Pseudomonas oleovorans and Pseudomonas putida (6, 10, 11) and Acinetobacter sp. (14, 23, 28, 29) have been studied. From these studies and from our research with the gaseous alkane utilizer P. butanovora, several differences among the enzymes involved in the metabolism of alkanes are starting to emerge. First, the essential enzymes in the utilization of the alkane differ in cellular location among these proteobacteria and P. butanovora. For example, the oxidation of octane in P. oleovorans and Acinetobacter sp. strain ADP1 proceeds through membrane-bound monooxygenases. In P. butanovora the oxidation of butane proceeds via a soluble alkane monooxygenase (D. Arp Laboratory, unpublished results). Second, the oxidation of the resulting alcohol in n-alkane metabolism proceeds via diverse enzymes depending on the bacterium. In P. oleovorans there is an inducible ADH which is a flavin-containing enzyme (43), while for P. butanovora BDH, an inducible PQQ- and heme c-containing ADH, has been described (45). Constitutive ADH activity was not detected in P. butanovora (33), while Acinetobacter sp. strain HO1-N has at least one constitutive ADH activity (35). Third, these alkane-utilizing proteobacteria have different gene arrangements. The genes coding for the enzymes in alkane metabolism in P. oleovorans are clustered in an operon (alk) (43), and in Acinetobacter sp. strain ADP1, the genes for alkane metabolism are spread through its chromosome (28, 29). The genetic arrangement of the genes for alkane metabolism in P. butanovora has not yet been determined. However, in P. butanovora, the genes for alkane metabolism may be arranged in different operons as in Acinetobacter sp. strain ADP1, since each enzyme activity in the butane oxidation pathway is induced independently by the substrate being oxidized (33). This study suggests that the NAD+-independent PQQ alcohol dehydrogenase BOH (a quinoprotein) is linked to butane metabolism in conjunction with the previously characterized BDH (a quinohemoprotein [45]). The inferred amino acid sequence of the gene coding for BOH (boh) showed a polypeptide similar to periplasmic PQQ-containing ADHs in other bacteria. The expression of boh was compared to the expression of bdh (encoding BDH). Inactivation of each gene coding for BOH or BDH decreased the rate of growth on butane, and inactivation of both genes eliminated the growth of P. butanovora on butane and on 1-butanol.
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Diversity in butane monooxygenases among butane-grown bacteria
1999Co-Authors: Natsuko Hamamura, Ryan T. Storfa, Lewis Semprini, Daniel J ArpAbstract:environmental isolate, CF8, were compared at the physiological level. The presence of butane monooxygenases in these bacteria was indicated by the following results. (i) O2 was required for butane degradation. (ii) 1-Butanol was produced during butane degradation. (iii) Acetylene inhibited both butane oxidation and 1-butanol production. The responses to the known monooxygenase inactivator, ethylene, and inhibitor, allyl thiourea (ATU), discriminated butane degradation among the three bacteria. Ethylene irreversibly inactivated butane oxidation by P. butanovora but not by M. vaccae or CF8. In contrast, butane oxidation by only CF8 was strongly inhibited by ATU. In all three strains of butane-grown bacteria, specific polypeptides were labeled in the presence of [14C]acetylene. The [14C]acetylene labeling patterns were different among the three bacteria. Exposure of lactate-grown CF8 and P. butanovora and glucose-grown M. vaccae to butane induced butane oxidation activity as well as the specific acetylene-binding polypeptides. Ammonia was oxidized by all three bacteria. P. butanovora oxidized ammonia to hydroxylamine, while CF8 and M. vaccae produced nitrite. All three bacteria oxidized ethylene to ethylene oxide. Methane oxidation was not detected by any of the bacteria. The results indicate the presence of three distinct butane monooxygenases in butane-grown P. butanovora, M. vaccae, and CF8. A number of bacteria can utilize gaseous and liquid alkane
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aerobic cometabolism of chloroform and 1 1 1 trichloroethane by butane grown microorganisms
Bioremediation Journal, 1997Co-Authors: Young Hoon Kim, Lewis Semprini, Daniel J ArpAbstract:Abstract Aerobic cometabolism of chloroform (CF) and 1,1,1-trichloroethane (1,1,1-TCA) was observed by subsurface microorganisms grown on butane. Studies performed in batch incubated microcosms were screened for CF transformation potential using the following cometabolic substrates: ammonia, methane, propane, butane, propene, octane, isoprene, and phenol. CF transformation was observed in microcosms fed ammonia, methane, propane, and butane. The butane microcosms achieved the most effective transformation. The transformation of CF and 1,1,1-TCA was strongly correlated with butane utilization and oxygen consumption. CF transformation ceased in the absence of butane or when oxygen was depleted to low concentrations in the microcosms. No transformation of carbon tetrachloride was observed. With successive additions of CF and butane to the microcosms, complete transformation of CF was achieved at solution concentrations as high as 1 mg/L. High CF concentrations appeared to inhibit butane utilization. Maximum ...
