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排序方式: 共有1268条查询结果,搜索用时 203 毫秒
81.
Poly(9,10-dihydrophenanthrene-2,7-diyl)s with -OSi(R)2(R′) groups at the 9,10-positions were synthesized by dehalogenative polycondensation of the corresponding monomers by using a zerovalent nickel complex. They showed number average molecular weights (Mn's) of 9800-69,000 and high quantum yields (62%-quantitative) in photoluminescence. Palladium catalyzed copolymerization of 2,7-dibromo-9,10-dihydrophenanthrene having -OCH3 or -OSi(R)2(R′) groups at the 9,10-positions with diethynyl- or diboronic-aromatic compounds also gave photoluminescent polymers with high quantum yields. 相似文献
82.
Ooki Kurihara Takashi Tsuchida Genki Takahashi Gyeong-o Kang Hiroki Murakami 《Soils and Foundations》2018,58(5):1173-1186
Great amounts of soil and waste contaminated with radioactive cesium have been generated due to the decontamination work after the Fukushima Daiichi Nuclear Power Plant accident. The aim of this study is to develop a sealing geomaterial for use at the disposal facilities of the soil and waste constructed in the maritime environment. The geomaterial consists of marine clay, bentonite, and zeolite. The hydraulic conductivity and cesium-adsorption performance of the geomaterial were examined through laboratory tests with different proportions of bentonite and zeolite added to marine clay. It was concluded that the hydraulic conductivity could be reduced to the required level by increasing the amount of bentonite and that the cesium-adsorption capacity could be enhanced by increasing the amount of zeolite. 相似文献
83.
Y. Nagasawa Y. Tachikawa E. Yamaguchi N. Tada T. Miura A. Itoh 《Advanced Synthesis \u0026amp; Catalysis》2016,358(2):178-182
A new catalytic method was developed for photo‐oxidizing the methyl group on aromatic heterocycles such as benzothiazole, benzoxazole, and quinoline to produce the corresponding aldehyde. This is the first report of the metal‐free catalytic synthesis of benzothiazole‐2‐carboxaldehydes using molecular oxygen as the terminal oxidant.
84.
Yoshinari Sawama Masahiro Masuda Ryosuke Nakatani Hiroki Yokoyama Yasunari Monguchi Toshifumi Dohi Yasuyuki Kita Hironao Sajiki 《Advanced Synthesis \u0026amp; Catalysis》2016,358(23):3683-3687
The iron(III) chloride‐catalyzed Friedel–Crafts arylation of 4‐aryl‐4‐methoxy‐2,5‐cyclohexadienones, which were easily prepared by the phenyliodine(III) diacetate (PIDA)‐mediated oxidation of 4‐arylphenols in methanol, proceeded site‐selectively to form meta‐terphenyl (2,4‐diarylphenol) derivatives in good yields. The subsequent PIDA‐mediated oxidation and iron(III) chloride‐catalyzed Friedel–Crafts arylation of the resulting products gave the corresponding 2,4,6‐triarylphenol derivatives. The present method provides useful highly substituted polyarylated compounds.
85.
Takatoshi Yamamoto Koji Fushimi Hiroki Habazaki Hidetaka Konno 《Electrochimica acta》2010,55(3):1232-8845
Depassivation-repassivation behavior on a pure iron surface in borate buffer solution was examined under potentiostatic control by a micro-indentation test. Current peaks emerge during both downward and upward drives of the indenter due to depassivation which is caused by plastic deformation of the substrate but not elastic deformation and repassivation. The total electric charge of the current peaks is proportional to the maximum load. The total electric charge also increases with increase in intermission time of the indentation, indicating that the passive film is ruptured even during stress relaxation. It is estimated from the electric charge balance that 82% and 18% of the film rupture occurs during the downward drive and intermission, respectively, and that no rupture occurs during the upward drive. Furthermore, the film-ruptured area is estimated to be 80% of the plastic deformed surface area. The partial retainment of the passive film on iron suggests that the ductility of the passive film is higher than that of the substrate. 相似文献
86.
Douglas A. Kuntz Dr. Shinichi Nakayama Kayla Shea Hitoshi Hori Prof. Dr. Yoshihiro Uto Dr. Hideko Nagasawa Prof. Dr. David. R. Rose Prof. Dr. 《Chembiochem : a European journal of chemical biology》2010,11(5):673-680
Golgi α‐mannosidase II (GMII) is a key enzyme in the N‐glycosylation pathway and is a potential target for cancer chemotherapy. The natural product swainsonine is a potent inhibitor of GMII. In this paper we characterize the binding of 5α‐substituted swainsonine analogues to the soluble catalytic domain of Drosophila GMII by X‐ray crystallography. These inhibitors enjoy an advantage over previously reported GMII inhibitors in that they did not significantly decrease the inhibitory potential of the swainsonine head‐group. The phenyl groups of these analogues occupy a portion of the binding site not previously seen to be populated with either substrate analogues or other inhibitors and they form novel hydrophobic interactions. They displace a well‐organized water cluster, but the presence of a C(10) carbonyl allows the reestablishment of important hydrogen bonds. Already approximately tenfold more active against the Golgi enzyme than the lysosomal enzyme, these inhibitors offer the potential of being extended into the N‐acetylglucosamine binding site of GMII for the creation of even more potent and selective GMII inhibitors. 相似文献
87.
Yoshida N Akazawa S Karino T Ishida H Hata Y Katsuragi T Tani Y Takagi H 《Journal of Bioscience and Bioengineering》2007,104(5):424-427
We found 11 genes (FAO1-11) encoding putative oxidoreductases in the Aspergillus oryzae genome, which are similar to fungal fructosyl-amino acid oxidases. The cDNAs corresponding to the genes were cloned and expressed in Escherichia coli. rFao2 had fructosyl-amino acid oxidase activity, whereas rFao1 did not show any enzyme activity, even though the deduced amino acid sequence of Fao1 is identical to that of one of the fructosyl-amino acid oxidase isozymes from Aspergillus oryzae. rFao7 and rFao8 showed oxidase activity toward sarcosine, L-pipecolate, and L-proline. rFao10 was active toward only sarcosine, of the substrates tested. The functions of the other proteins were also predicted from a phylogenetic analysis. 相似文献
88.
Ishiwata H Abe Y Kubota H Kawasaki Y Takeda Y Maitani T Nishijima M Fukasawa Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(1):49-56
The mean concentrations and daily intake of four antifungal agents were estimated based on the results of an analysis of 7,005 samples of food obtained in official inspections by Japanese local governments in fiscal year 1998. The mean concentration of diphenyl was 0.0004% of the allowable limit, and those of imazalil, o-phenylphenol, and thiabendazole were 14.0%, 3.5%, and 5.7%, respectively. The daily intakes of these antifungal agents per person, estimated from their concentrations and the daily consumption of the foods, were 0.000326, 1.89, 11.5, and 23.3 micrograms, respectively, and assuming a body weight of 50 kg, the amounts of these antifungal agents consumed were 0.000013%, 0.15%, 0.12%, and 0.47% of the acceptable daily intake, respectively. These values are similar to the values obtained on the basis of the results of the official inspection in fiscal years 1994 and 1996, except that the amount of diphenyl is much lower (1/100). 相似文献
89.
Yu Matsuda Toru Uchida Suguru Suzuki Ryota Misaki Hiroki Yamaguchi Tomohide Niimi 《Microfluidics and nanofluidics》2011,10(1):165-171
For the development of micro- and nano-technology, it has been strongly desired to understand thermo-fluid phenomena inside
or around micro- and nano-devices. An optical measurement technique based on the absorption and the emission of photons by
molecules is useful for experimental analyses of thermo-fluid phenomena of micro and nanoflows. The pressure-sensitive paint
(PSP) technique is a potential diagnostic tool for pressure measurements of micro/nano gas flows because it works as a so-called
“molecular sensor”. However, the micro-scale measurement of PSP has been limited by the aggregation of the luminescent molecules
and their thick film due to the use of a polymer binder. In our previous work, we adopted the Langmuir–Blodgett (LB) technique
to fabricate pressure-sensitive molecular film (PSMF) with ordered molecular assemblies, and investigated properties of PSMF.
In this study, a novel approach to enhance the luminescent intensity of PSMF is proposed, and the pressure distribution in
a micro-nozzle is successfully measured by using PSMF. Moreover, we compared the pressure distribution measured by PSMF with
that numerically analyzed by the direct simulation monte carlo (DSMC) method, showing good agreement with each other. 相似文献
90.