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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.
Daniel J Arp - One of the best experts on this subject based on the ideXlab platform.
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Diversity in Butane monooxygenases among Butane-grown bacteria
1999Co-Authors: Natsuko Hamamura, Lewis Semprini, Ryan T. Storfa, 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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chloroform cometabolism by Butane grown cf8 pseudomonas butanovora and mycobacterium vaccae job5 and methane grown methylosinus trichosporium ob3b
Applied and Environmental Microbiology, 1997Co-Authors: Natsuko Hamamura, Cynthia Page, Tulley Long, Lewis Semprini, Daniel J ArpAbstract:Chloroform (CF) degradation by a Butane-grown enrichment culture, CF8, was compared to that by Butane-grown Pseudomonas butanovora and Mycobacterium vaccae JOB5 and to that by a known CF degrader, Methylosinus trichosporium OB3b. All three Butane-grown bacteria were able to degrade CF at rates comparable to that of M. trichosporium. CF degradation by all four bacteria required O(inf2). Butane inhibited CF degradation by the Butane-grown bacteria, suggesting that Butane monooxygenase is responsible for CF degradation. P. butanovora required exogenous reductant to degrade CF, while CF8 and M. vaccae utilized endogenous reductants. Prolonged incubation with CF resulted in decreased CF degradation. CF8 and P. butanovora were more sensitive to CF than either M. trichosporium or M. vaccae. CF degradation by all three Butane-grown bacteria was inactivated by acetylene, which is a mechanism-based inhibitor for several monooxygenases. Butane protected all three Butane-grown bacteria from inactivation by acetylene, which indicates that the same monooxygenase is responsible for both CF and Butane oxidation. CF8 and P. butanovora were able to degrade other chlorinated hydrocarbons, including trichloroethylene, 1,2-cis-dichloroethylene, and vinyl chloride. In addition, CF8 degraded 1,1,2-trichloroethane. The results indicate the potential of Butane-grown bacteria for chlorinated hydrocarbon transformation.
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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 ...
Stephen Raymond Schmidt - One of the best experts on this subject based on the ideXlab platform.
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continuous liquid phase hydrogenation of 1 4 butynediol to high purity 1 4 Butanediol over particulate raney nickel catalyst in a fixed bed reactor
Organic Process Research & Development, 2017Co-Authors: Setrak K Tanielyan, Santosh R More, Robert L Augustine, Stephen Raymond SchmidtAbstract:The work describes the results on the hydrogenation of the 2-butyne-1,4-diol (BYD) to 1,4-Butanediol (BAD) over both slurry and particulate Raney nickel catalysts (Ra Ni) in batch and in a fixed bed reactor system. The detailed study on the kinetics of the reaction obtained in batch conditions revealed the existence of four stages in the overall hydrogenation network. In the first region, A, the starting BYD produces exclusively cis-2-butene-1,4-diol (cis-BED) and to a lesser degree the respective 4-hydroxybutanal (γ-HALD). In the second region, B, the cis-BED takes part in three parallel reactions of hydrogenation to BAD, isomerization to trans-2-butene-1,4-diol (trans-BED), and the formation of additional γ-HALD. In the third region, C, the trans-BED is mostly engaged in further hydrogenation to BAD, and surprisingly, starts producing the main byproduct, n-butanol (BOL). In the last kinetic region, D, the accumulated 4-hydroxybutanal is slowly hydrogenated to BAD. A completely different reaction profile...
Sunney I Chan - One of the best experts on this subject based on the ideXlab platform.
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the stereospecific hydroxylation of 2 2 2h2 Butane and chiral dideuterioButanes by the particulate methane monooxygenase from methylococcus capsulatus bath
Journal of Biological Chemistry, 2003Co-Authors: Kelvin H C Chen, Weni Luo, Dedshih Huang, Sunney I ChanAbstract:Abstract Experiments on cryptically chiral ethanes have indicated that the particulate methane monooxygenase (pMMO) from Methylococcus capsulatus (Bath) catalyzes the hydroxylation of ethane with total retention of configuration at the carbon center attacked. This result would seem to rule out a radical mechanism for the hydroxylation chemistry, at least as mediated by this enzyme. The interpretation of subsequent experiments on n-propane, n-Butane, and n-pentane has been complicated by hydroxylation at both the pro-R and pro-S secondary C–H bonds, where the hydroxylation takes place. It has been suggested that these results merely reflect presentation of both the pro-R and pro-S C–H bonds to the hot “oxygen atom” species generated at the active site, and that the oxo-transfer chemistry, in fact, proceeds concertedly with retention of configuration. In the present work, we have augmented these earlier studies with experiments on [2,2-2H2]Butane and designed d,l form chiral dideuterioButanes. Essentially equal amounts of (2R)-[3,3-2H2]butan-2-ol and (2R)-[2-2H1]butan-2-ol are produced upon hydroxylation of [2,2-2H2]Butane. The chemistry is stereospecific with full retention of configuration at the secondary carbon oxidized. In the case of the various chiral deuterated Butanes, the extent of configurational inversion has been shown to be negligible for all the chiral Butanes examined. Thus, the hydroxylation of Butane takes place with full retention of configuration in Butane as well as in the case of ethane. These results are interpreted in terms of an oxo-transfer mechanism based on side-on singlet oxene insertion across the C–H bond similar to that previously noted for singlet carbene insertion (Kirmse, W., and Ozkir, I. S. (1992) J. Am. Chem. Soc. 114, 7590-7591). Finally, we discuss how even the oxene insertion mechanism, with “spin crossover” in the transition state, could lead to small amounts of radical rearrangement products, if and when such products are observed. A scheme is described that unifies the two extreme mechanistic limits, namely the concerted oxene insertion and the hydrogen abstraction radical rebound mechanism within the same over-arching framework.
Stephen J Lippard - One of the best experts on this subject based on the ideXlab platform.
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tritiated chiral alkanes as substrates for soluble methane monooxygenase from methylococcus capsulatus bath probes for the mechanism of hydroxylation
Journal of the American Chemical Society, 1997Co-Authors: Ann M. Valentine, Barrie Wilkinson, Sonja Komarpanicucci, Nigel D Priestley, Philip G Williams, Hiromi Morimoto, Heinz G Floss, Stephen J LippardAbstract:The tritiated chiral alkanes (S)-[1-2H1,1-3H]ethane, (R)-[1-2H1,1-3H]ethane, (S)-[1-2H1,1-3H]Butane, (R)-[1-2H1,1-3H]Butane, (S)-[2-3H]Butane, (R)-[2-3H]Butane, and racemic [2-3H]Butane were oxidized by soluble methane monooxygenase (sMMO) from Methylococcus capsulatus (Bath), and the absolute stereochemistry of the resulting product alcohols was determined in order to probe the mechanism of substrate hydroxylation. When purified hydroxylase, coupling protein, and reductase components were used, the product alcohol displayed 72% retention of stereochemistry at the labeled carbon for the ethane substrates and 77% retention for the Butanes labeled at the primary carbon. A putative alkyl radical which would yield these product distributions would have a lifetime of 100 fs, a value too short to correspond to a discrete intermediate. Intramolecular kH/kD ratios of 3.4 and 2.2 were determined for ethane and Butane, respectively. When the hydroxylations were performed with purified hydroxylase but only a partial...
