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991.
992.
Bungo Ochiai Tomomi Nagasawa Yasuhiro Asano Daisuke Nagai Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2007,45(13):2820-2826
Thermal behaviors were monitored by infrared thermographic analysis in the copolymerization of a spiroorthoester and a bifunctional oxetane with thermally latent initiators [benzyl tetrahydrothiophenium hexafluoroantimonate (BTHT) and benzyl 4‐hydroxyphenyl methyl sulfonium hexafluoroantimonate (BPMS)]. The copolymerization with BPMS increased the temperature during the copolymerization more than that with BTHT, whereas the exothermicities were lowered with the increase in the initial feed ratio of the spiroorthocarbonate monomer. The high exothermicity in the copolymerization with BPMS is ascribable to the faster propagation of the oxetane monomer with a high heat of polymerization, and this is supported by model reactions and computational calculation. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2820–2826, 2007 相似文献
993.
Takeshi Furuta Shuichi Ikefuji Koujirou Tokunaga Tze Loon Neoh Hidefumi Yoshii 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):21-27
Recently, air and ground water pollution and contamination of soil by toluene have been drawing increasing attention and became
an urgently important problem in environmental pollution. Hence, the development of highly sophisticated removal techniques
of toluene is required for the global environmental preservation. Since toluene is a highly volatile material, it is difficult
to treat it by usual activated sludge water treatment. In this study, in order to prevent volatilization of toluene, randomly
methylated β-cyclodextrin (RM-β-CD) was used to complex with toluene and by reason of that, facilitates the biodegradation
of toluene by activated sludge. The enhanced effect of RM-β-CD for the biodegradation of toluene by activated sludge was studied
in batch systems. The addition of RM-β-CD dominantly promoted proliferation of activated sludge. This implied that the addition
of RM-β-CD prevented toluene from evaporating during treatment, and as a result, toluene was effectively decomposed by the
activated sludge. 相似文献
994.
Two-dimensional quantum fields in electric and gravitational backgrounds can be described by conformal field theories, and hence all the physical (covariant) quantities can be written in terms of the corresponding holomorphic quantities. In this paper, we first derive relations between covariant and holomorphic forms of higher-spin currents in these backgrounds, and then, by using these relations, obtain higher-spin generalizations of the trace and gauge (or gravitational) anomalies up to spin 4. These results are applied to derive higher-moments of Hawking fluxes in black holes in a separate paper [S. Iso, T. Morita, H. Umetsu, Hawking radiation via higher-spin gauge anomalies, arXiv: 0710.0456 [hep-th]]. 相似文献
995.
It is shown that the Dirac equations in general higher dimensional Kerr–NUT–de Sitter spacetimes are separated into ordinary differential equations. 相似文献
996.
Takeshi Ito Tetsuya Hiroi Satoru Kaneko Toshiyuki Ohsawa Kunio Matsumoto 《Talanta》2009,77(3):1185-712
We designed and prepared a micro biosensing system consisting of a flow through system with a sub-micro liter injection valve and a sub-micro liter volume bioreactor. An electrochemical detector was combined with the reactor for immediate detections. The volumes of the reactor and the sample loop for the injection were 850 nl and 320 nl, respectively. This paper described about the characteristics of the sensing system in the case of histamine detection for food analysis. Histamine oxidase from KAIT-B-007 was prepared by using a gene recombination technique and they were immobilized with chitosan beads (? = 70-105 μm). The detection less than one minute after injection made possible fast analysis for histamine. The biosensing system also showed a high performance for histamine detection in wide range of 1 μM-1 mM. In addition, we practically measured histamine content in raw tuna stored at room temperature and 35 °C up to 96 h. As a result of the comparison between our sensing system and HPLC method, there was good agreement. These results show that our microfluidic biosensing system has the potential to assist miniaturization with small sample volume and short determination time for a sequential food analysis. 相似文献
997.
Better understandings of the nature of Co–Mo sulfide catalysts are of great importance to a rational design of highly active hydrodesulfurization catalysts on a molecular level. Synthesis of uniform binary sulfide clusters well-defined in structure and thermally stabilized on a support is desirable for such purposes. In the present study, successful preparations, using metal carbonyls as precursors, of Mo, Co and Co–Mo sulfide clusters encaged in zeolite are reported. The structure, location and catalytic properties of the clusters are described on the basis of XPS, XAFS, XRD, XRF, IR, HREM and adsorptions of benzene and NO. Implications for the generation of catalytic synergy between Co and Mo sulfides are presented in brief. It is suggested that the host–guest interactions between zeolite framework oxygens and precursor molecules and product clusters are crucial to the size and structure of the intrazeolite clusters. 相似文献
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