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991.
992.
993.
Yonehara K Kamata K Yamaguchi K Mizuno N 《Chemical communications (Cambridge, England)》2011,47(6):1692-1694
A divanadium-substituted phosphotungstate TBA(4)[γ-HPV(2)W(10)O(40)] (TBA = tetra-n-butylammonium) could act as an effective homogeneous catalyst for the H(2)O(2)-based oxidative bromination. 相似文献
994.
Kazuhiro Oeda 《Journal of Differential Equations》2011,250(10):3988-4009
This paper is concerned with the stationary problem of a prey-predator cross-diffusion system with a protection zone for the prey. We discuss the existence and non-existence of coexistence states of the two species by using the bifurcation theory. As a result, it is shown that the cross-diffusion for the prey has beneficial effects on the survival of the prey when the intrinsic growth rate of the predator is positive. We also study the asymptotic behavior of positive stationary solutions as the cross-diffusion coefficient of the prey tends to infinity. 相似文献
995.
Mutual solubility data of imidazolium-based ionic liquid, 1-butyl-2,3-dimethylimidazolium tetrafluoroborate ([bmmim][BF4]) with the alcohols, 1-propanol, 2-propanol, 1-butanol, 1-pentanol, and 1-hexanol were obtained by a cloud point method. The upper critical solution temperatures of the ionic liquid and alcohol mixtures were determined from the mutual solubility data. The upper critical solution temperature of the binary mixtures gradually increased as the chain length of the alcohol increased. The mutual solubility data of binary systems ([bmmim][BF4] + alcohols) have been correlated by the original UNIQUAC model as well as the extended and modified form of the UNIQUAC model. The temperature dependence of the mutual solubility data could be represented in terms of the temperature dependence of the binary energy parameters obtained from the correlation. Additionally the influence of water contamination on the ionic liquid mixture was shown experimentally by adding pure water into the binary mixture ([bmmim][BF4] + 1-butanol). 相似文献
996.
(Ternary liquid + liquid) equilibria (tie-lines) of (water + acetone + α-pinene) at T = (288.15, 298.15, and 308.15) K and (water + acetone + β-pinene, or limonene) at T = 298.15 K have been measured. The experimental (ternary liquid + liquid) equilibrium data have been correlated successfully by the original UNIQUAC and modified UNIQUAC models. The modified UNIQUAC model reproduced accurately the experimental results for the (water + acetone + α-pinene) system at all the temperatures but fairly agreed with the experimental data for the (water + acetone + β-pinene, or limonene) systems. 相似文献
997.
Yoh-ichi Matsushita Kazuhiro Sugamoto Yoshihisa Iwakiri Satoru Yoshida Takehito Chaen Takanao Matsui 《Tetrahedron letters》2010,51(30):3931-3934
Methyl 8,11,13-abietatriene-18-oate (1b) and 7-oxo-8,11,13-abietatrienes 10 and 15 were converted into 15-hydroperoxy-7-oxo-8,11,13-abietatrienes 13 and 16 by aerobic oxidation catalyzed by N-hydroxyphthalimide (NHPI) combined with 2,2′-azobis(4-methoxy-2,4-dimethylvaleronitrile) (V-70) at room temperature, and several abietane and podocarpane terpenes were synthesized from 13 and 16. 相似文献
998.
Kanda M Kusano T Kanai S Hayashi H Matushima Y Nakajima T Takeba K Sasamoto T Nagayma T 《Journal of AOAC International》2010,93(4):1331-1339
A rapid and efficient method was developed for the simultaneous determination of seven fluoroquinolone (FQ) residues: norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, orbifloxacin, sarafloxacin, and difloxacin in honey. The samples were first screened with a microbiological method by using test plates made from metal-free purified agar seeded with Bacillus subtilis BGA. When a sample was found to contain FQ residues by using the microbiological method, it was analyzed by LC with fluorescence detection (LC/FL). FQs were extracted with Na2EDTA-McIlvaine buffer and purified by a dual SPE method in which a cation-exchange cartridge was connected to an anion-exchange cartridge. The overall recoveries of the seven FQs ranged from 70.0 to 92.1%. The intra-assay and interassay CVs were < or = 7.8 and < or = 5.1%, respectively. For the microbiological method, the LOD values ranged from 2 to 9 microg/kg. For LC/FL, the LOQ values ranged from 2 to 7 microg/kg. The developed method was used to analyze 70 honey samples. In 14 samples in which the microbiological method detected the presence of FQ residues, norfloxacin, ciprofloxacin, and enrofloxacin were identified by LC/FL. 相似文献
999.
Suzuki S Fukui K Fuyuhiro A Sato K Takui T Nakasuji K Morita Y 《Organic letters》2010,12(21):5036-5039
Symmetric hexaazaphenalenes (R = phenyl and tert-butyl) have been synthesized by one-pot condensations of corresponding amidine hydrochlorides with tricyanomethanide. The hexaazaphenalenes are linked with each other by a N-H···N hydrogen-bonding interaction in the crystalline states. Interestingly, a planar and achiral tert-butylated derivative was crystallized in a chiral space group with assembly of one-handed helical hydrogen-bonded chains. Hexaazaphenalenyl anions were isolated as air- and water-stable tetraethyl ammonium salts. 相似文献
1000.
Shinsuke Fukuoka Isaburo Fukawa Masahiro Tojo Kazuhiro Oonishi Hiroshi Hachiya Muneaki Aminaka Kazumi Hasegawa Kyosuke Komiya 《Catalysis Surveys from Asia》2010,14(3-4):146-163
This paper focuses on the world’s first non-phosgene process using CO2 as starting material succeeded in development and industrialization by Asahi Kasei Corp. The Asahi Kasei Process enables high-yield production of high-quality PC having excellent properties and high-purity monoethylene glycol (MEG), starting from ethylene oxide (EO), by-produced CO2 and bisphenol-A without waste and waste water. The innovative reactive distillation technologies in the monomer production and the innovative gravity-utilized, non-agitation polymerization reactor in the melt polymerization, led the new process to success. The monomer process consists of 3 production steps, ethylene carbonate (EC) from CO2 and EO, dimethyl carbonate (DMC) and MEG from EC and MeOH, and diphenyl carbonate (DPC) and MeOH from DMC and PhOH. All intermediates are recycled. The new type polymerization reactor perfectly overcomes the difficulty based on the extremely high viscosity in the melt polymerization of DPC with Bis-A. The by-produced PhOH is recycled to the monomer process. The reduction of CO2 emissions (0.173t/PC 1t) is also achieved, because CO2 used as raw material is utilized as the main chain components of the products. Four commercial plants (Taiwan: 150,000 t/y, Korea: 2 plants of 65,000 t/y, Russia: 65,000 t/y) using the Asahi Kasei Process are now successfully operating, and the plant of 260,000 t/y in Saudi Arabia will start in 2010. 相似文献