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141.
Hyperbranched polysiloxysilane (HBPS) terminated by the vinyl functional group was synthesized by the self polymerization of AB2 monomer, 1,5-divinyl-1,1,3,5,5-pentamethyltrisiloxane, in the presence of the platinum catalyst. The terminal vinyl group was converted to 2-hydroxyethyl by the reaction with 9-BBN as the hydroboration reagent. The terminal function was then modified to the 2-bromoisobutyryl group by the reaction of hydroxyl group with 2-bromoisobutyryl bromide. The obtained HBPS possessing the 2-bromoisobutyryl terminal group was immobilized on the silica surface by mixing the silica bead and HBPS in hexane. Block copolymer of HBPS and poly(N-isopropylacrylamide) (PIPAAm) was synthesized by the atom transfer radical polymerization (ATRP) using 2-bromoisobutyryl terminated HBPS as a macroinitiator. The molecular weight of the block copolymer was Mn=23,500 and Mw/Mn=1.31. Graft polymerization of N-isopropylacrylamide on the silica surface was carried out on the 2-bromoisobutyryl terminated HBPS immobilized silica bead using ATRP. The PIPAAm grafted silica bead was applied to the column packed material for temperature-responsive HPLC. Two kinds of steroids, hydrophilic and hydrophobic, were successfully separated by the HPLC system. 相似文献
142.
Fabrication of high-power electric double-layer capacitors 总被引:7,自引:0,他引:7
Yukari Kibi Takashi Saito Mitsuyoshi Kurata Junji Tabuchi Atsushi Ochi 《Journal of power sources》1996,60(2):219-224
The electrochemical behavior of activated carbon/carbon (AC/C) composite electrodes was investigated for high-power electric doublelayer capacitors (EDLCs). It was found that high-rate charge/discharge characteristics are affected by the resistance of the electrolyte phase in the pores of the electrode. The charge/discharge characteristics were improved by optimizing the pore-size distribution of the electrodes. The size and total volume of the macro-pores in the electrodes were controlled by mixing and burning out polymer spheres. A high-power EDLC (15V, 470 F), which can discharge as much as 500 A, was fabricated by using improved AC/C composite electrodes. 相似文献
143.
Selective Catalytic Reduction of NO by C3H6 over Co/Al2O3 Catalyst with Extremely Low Cobalt Loading 总被引:1,自引:0,他引:1
Tatsuro Horiuchi Takamichi Fujiwara Laiyuan Chen Kenzi Suzuki Toshiaki Mori 《Catalysis Letters》2002,78(1-4):319-323
In order to reveal the optimum Co loading, the selective catalytic reduction of NO with C3H6 over Co/Al2O3 catalyst was studied in a systematic fashion by varying the amount of cobalt oxide. It was found that upon loading a small amount of cobalt oxide (namely 0.5 wt% on a Co metal basis), the combination between Co(II) acetate salt and a high-purity alumina provided an active catalyst in the presence of excess oxygen and water. TPR measurement showed the presence of Co species other than CoAl2O4 spinel in the most excellent performance catalyst, from which the active sites should be produced. 相似文献
144.
Toshihiko Eki Masanori Naitou Hiroko Hagiwara Masashi Ozawa Shun-Ichi Sasanuma Motoe Sasanuma Yukari Tsuchiya Takehiko Shibata Fumio Hanaoka Yasufumi Murakami 《Yeast (Chichester, England)》1996,12(2):149-167
The nucleotide sequence of a 36·2-kb distal region containing the right telomere of chromosome VI was determined. Both strands of DNA cloned into cosmid clone 9965 and plasmid clone pEL174P2 were sequenced with an average redundancy of 7·9 per base pair, by both dye primer and dye terminator cycle sequencing methods. The G + C content of the sequence was found to be 37·9%. Eighteen open reading frames (ORFs) longer than 100 amino acids were detected. Four of these ORFs (9965orfR017, 9965orfF016, 9965orfR009 and 9965orfF003) were found to encode previously identified genes (YMR31, PRE4, NIN1 and HXK1, respectively). Six ORFs (9965orfR013, 9965orfF018, 9965orfF006, 9965orfR014, 9965orfF013 and 9965orfR020) were found to be homologous to hypothetical 121·4-kDa protein in the BCK 5′ region, Bacillus subtilis DnaJ protein, hypothetical Trp-Asp repeats containing protein in DBP3-MRPL27, putative mitochondrial carrier YBR291C protein, Salmonella typhimurium nicotinate-nucleotide pyrophosphorylase, and Escherichia coli cystathionine β-lyase, respectively. The putative proteins encoded by 9965orfF018, 9965orfR014 and 9965orfR020 were found to be, respectively, a new member of the family of DnaJ-like proteins, the mitochondrial carrier protein and cystathionine lyase. The nucleotide sequence reported here has been deposited in the DDBJ/GenBank/EMBL data library under Accession Number D44597. 相似文献
145.
This paper aims to develop a systematized theory on the thinking process at the ‘very early stage of design.’ Here, ‘very’ is used to exaggerate the beginning of design, which includes the time just prior to or the precise beginning of the so-called conceptual design. First, concept generation is segregated into two phases—the problem-driven phase and the inner sense-driven phase. With regard to theoretical approach, the concept generation process is discussed by comparing metaphor, abduction, and general design theory from the perspective of similarities and dissimilarities. In addition, property mapping, concept blending, and concept integration in thematic relation are explained methodologically. So far, these theories and methods have been discussed independently, and the relations among them have not been clarified. As a result, it was found that the concept generation process could be categorized into two types: first-order concept generation and high-order concept generation. Furthermore, it was shown that high-order concept generation is related to the inner sense-driven phase, whereas first-order concept generation is related to the problem-driven phase. 相似文献
146.
147.
Ken‐Ichi Ikeda Kanako Inoue Satoko Kanematsu Yoshitaka Horiuchi Pyoyun Park 《Microscopy research and technique》2011,74(9):825-830
This ultrastructural study showed that nonisotopic methanolic hafnium chloride and aqueous lead solution was an excellent new electron stain for enhancing TEM contrasts of fungal and plant cell structures. The ultrastructural definition provided by the new stain was often superior to that provided by conventional staining with uranyl acetate and lead. Definition of fine ultrastructure was also supported by quantitative data on TEM contrast ratios of organelles and components in fungal and plant cells. In particular, polysaccharides, which were localized in cell walls, glycogen particles, starch grains, and plant Golgi vesicle components, were much more reactive to the new stain than to the conventional one. The new nonisotopic stain is useful for enhancing the contrast of ultrastructure in biological tissues and is a safer alternative to uranyl acetate. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc. 相似文献
148.
S Kitajima S Sakuma Y Uchinuno T Terano A Miyazaki H Hakamata S Horiuchi 《Canadian Metallurgical Quarterly》1996,58(9):855-860
A simple method to quantitatively evaluate atherosclerosis in the rabbit coronary arteries by measuring macroscopic lesion areas (%) was attempted in the present study. Sixteen rabbits were fed a 0.5% cholesterol diet for 15 weeks and then 9 rabbits were sacrificed whereas the remaining 7 rabbits were maintained for further 9 weeks on a normal chow (at week 24). The left circumflex coronary arteries (LCX) were excised from the rabbit hearts under stereoscopic observation. The prepared arterial strips of LCX were 38.7 +/- 7.1 mm long and all of them reached the cardiac apex from the orifice. At week 15, the lesion area in LCX was negligible (3.2 +/- 0.4%) whereas the aortic lesions significantly developed (50.0 +/- 7.6%). At week 24, atherosclerotic lesions in both LCX and aortas increased to 32.8 +/- 9.2% and 85.9 +/- 5.6%, respectively. This is the first report that determined the luminal surface areas of atherosclerotic lesions in rabbit coronary arteries. This method may be more practical and useful for quantitative evaluation of coronary atherosclerosis in a large number of rabbits than histological observations of serial sections of rabbit hearts. 相似文献
149.
A case of multiple small intestinal stromal tumors (SIST) with skeinoid fibers of the jejunum arising in a 50 year old male with neurofibromatosis 1 (NF-1) is reported. Seven small tumors of the jejunal wall were incidentally found and excised during an operation for abdominal and retroperitoneal neurofibromas. Histologically, the tumors were composed of uniform spindle-shaped cells with fascicular pattern, almost indistinguishable from the histology in leiomyoma. Periodic acid Schiff stain-positive hyaline globules were observed among the tumor cells. Ultrastructurally, these globules were stromal tangles of curvilinear, fluffy fibrils, consistent with skeinoid fibers. The electron-dense granules, possibly neuro-secretory granules, were found in the cytoplasm of the tumor cells. Immunohistochemically, the tumor cells were positive for vimentin, neuron specific enolase and CD34, but negative for muscle markers and S100 protein. The association of NF-1 and multiple SIST with skeinoid fibers may have clinical implications. The multiple occurrence of SIST with skeinoid fibers seems to be often cited as one of the gastrointestinal manifestations of NF-1. The possible site of origin of SIST with skeinoid fibers in NF-1 may be the enteric autonomic nerve plexus in the small intestinal wall. 相似文献
150.
We determined the minimum inhibitory concentration (MIC) of DR-3355, a newly developed quinolone-derivative antibacterial agent, against clinical isolates of various bacterial species from enteritis patients, and compared them with those of ofloxacin (OFLX), ciprofloxacin (CPFX), nalidixic acid (NA), ampicillin (ABPC), kanamycin (KM). MIC90 of DR-3355 against 94 strains of Shigella spp. and 5 strains of Escherichia coli, 36 strains of Salmonella spp., 22 strains of Vibrio cholerae, 5 strains of Vibrio parahaemolyticus, and 19 strains of Campylobacter jejuni were 0.05, 0.10, 0.0025, 0.39, and 0.78 micrograms/ml, respectively. These values were 1/2 of that of OFLX, and two times of that of CPFX. MIC90 of DR-3355, OFLX and CPFX against C. jejuni were 0.78 micrograms/ml. MIC90 of DR-3355 against isolates from enteritis patients except for Vibrio spp., were 1/30 to 1/60 of those of NA, ABPC, and KM. 相似文献