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排序方式: 共有368条查询结果,搜索用时 31 毫秒
1.
K Sudo Y Matsumoto M Matsushima M Fujiwara K Konno K Shimotohno S Shigeta T Yokota 《Canadian Metallurgical Quarterly》1997,238(2):643-647
This study evaluated the inhibitory effects of thiazolidine derivatives on hepatitis C virus (HCV) protease and other human serine proteases. The inhibition efficacy was tested with a reversed-phase high-performance liquid chromatography (HPLC) assay system using a NS3-NS4A fusion protein as the HCV protease and a synthetic peptide substrate that mimics the NS5A-5B junction. Nine thiazolidine derivatives showed more than 50% inhibition at 50 microg/ml. The most potent derivative was RD4-6250, with 50% inhibition at a concentration of 2.3 microg/ml; this concentration was lower than those of other protease inhibitors reported previously. The most selective derivative was RD4-6205, with 50% inhibition at a concentration of 6.4 microg/ml, a lower concentration than those on other serine proteases (chymotrypsin, trypsin, plasmin, and elastase). These results suggest that the RD4-6205 skeleton is an important structure for inhibitory activity on the HCV protease NS3-NS4A. 相似文献
2.
Katsukiyo Marukawa Shigeta HARA Hirotoshi KAWABATA Hideki ONO-NAKAZATO Tateo USUI Toshihiro TANAKA Hongzhi SHI 《钢铁》2003,38(Z1):73-75
目前在日本,存在大量工业垃圾,包括各种塑料制品,ASR(汽车破碎垃圾),含有毒PCB(多氯联苯)的110变压器和PVC(聚氯乙稀)制品等.而来自城市垃圾焚烧炉的废气含有大量能量.因此,在充分考虑环境、避免二垩英生成的同时,安全回收来自工业垃圾、城市和/或工业垃圾焚烧炉的资源和能量是个非常重要的课题,这也将对抑制CO2排放作出贡献.正确地阐明焚烧过程中二垩英的生成机理及详细研究含少量二垩英的焚烧废气在冷却过程中大量形成二垩英的临界温度是项很重要的工作.解决这个问题可有效实现资源和能量的回收.本报告介绍日本在二垩英排放方面目前采取的对策和存在的问题以及大阪大学为阻止二垩英生成所做的基础研究工作. 相似文献
3.
Time-series primitive static states for detailing work state and flow of human-operated work machine
This paper proposes a quantification method for a comprehensive work flow in construction work for describing work states in more detail on the basis of analyzing state transitions of primitive static states (PSS), which consist of 16 symbolic work states defined by using on-off state of the lever operations and joint loads for the manipulator and end-effector. On the basis of the state transition rules derived from a transition-condition analysis, practical state transitions (PST), which are common and frequent transitions in arbitrary construction work, are defined. PST can be classified into essential state transition (EST) or nonessential state transitions (NST). EST extracts common phases of work progress and estimates positional relations between a manipulator and an object. NST reveals wasted movements that degrade the efficiency and quality of work. To evaluate comprehensive work flows modeled by combining EST and NST, work-analysis experiments using our instrumented setup were conducted. Results indicate that all the PSS definitely changes on the basis of PST under various work conditions, and work analysis using EST and NST easily reveals work characteristics and untrained tasks related to wasted movements. 相似文献
4.
Somsak Vivatpanachart Hiroyasu Nomura Yutaka Miyahara Hisatsugu Kashiwabara Masato Sakaguchi 《Polymer》1981,22(7):896-901
E.s.r. spectra of chain-end spin labels on the surface of polyethylene powder were obtained for high and low density polyethylene samples at various stages of heat treatment process. The subsequent crystalline structures of the samples were examined with wide angle and small angle X-ray diffraction spectra. The effects of annealing on the motion of the labels were dependent on annealing temperature and the type of the samples. Higher temperature annealing decreased the rotational correlation times (τc) and their activation energy in high density polyethylene but did not affect those of low density polyethylene. Melting decreases the values of τc and ΔE for both high an low density polyethylene samples. The cause of these decreases were attributed to the changing of the sites of the chain-end labels. The motion of the labels appeared to be influenced by the local segmental motion of the polymer main chains. 相似文献
5.
Kazuyori Urabe Hiromi Nakano Hiroyasu Morita 《Journal of the American Ceramic Society》2002,85(2):423-429
Structural modulations in solid solutions of C3 S doped with various amounts of ZnO were investigated via the selected-area electron diffraction method. Three monoclinic modifications (M(I), M(II), and M(III)) were identified in the solid solutions. The modifications had pseudohexagonal subcells that were modulated to form supercells. Coordinates of the reflections attributable to the supercells could be expressed by the following linear combinations of vectors of the reciprocal lattices: m1 (−2 a */5.4 + 2 b */5.4 − 7 c */5.4) for M(I), m2 (− a */5 + b */5 − c *) for M(II), and m3 (− a */6 + b */6 + 7 c */6) for M(III), m1 and m2 =±1 and ±2, and m3 =±1, ±2, and ± 3. All the monoclinic modifications possessed structural modulations of a one-dimensional type. The modulation waves could be detected as wavy contrasts by high-resolution transmission electron microscopy. 相似文献
6.
Zhaoxia Song Hiroyasu Nishiguchi Wei Liu Hiroshi Yamada Akihide Takami Kumiko Kudo Katsutoshi Nagaoka Yusaku Takita 《Catalysis Letters》2006,111(3-4):169-171
Redox properties of CeO2 and Pt-Rh/CeO2 were studied by temporal analysis of products (TAP) method using alternative pulses of CO and O2. A portion of pulsed CO was oxidized to CO2 and a portion of CO was adsorbed on the surface. Pulsing 18O2 onto the catalyst which has surface species derived from CO, evolved CO2 contained no 18O suggesting that the surface species will be carbonate ions. 相似文献
7.
Tsunehiro Aki Kazutaka Hachida Megumi Yoshinaga Yuko Katai Takashi Yamasaki Seiji Kawamoto Toshihide Kakizono Takashi Maoka Seiko Shigeta Osamu Suzuki Kazuhisa Ono 《Journal of the American Oil Chemists' Society》2003,80(8):789-794
Thraustochytrids, marine protists whose dominant genera are Thraustochytrium and Schizochytrium, belong to the kingdom Chromista and are known as an industrial source of DHA. We describe here that thraustochytrid strain
KH105, isolated as a DHA producer, also accumulates significant levels of β-carotene and xanthophylls including canthaxanthin
and astaxanthin. A4-d cultivation using a medium composed of 10% glucose and less than 0.3% of nitrogen sources in a half-concentration
of seawater gave an astaxanthin production up to 6.1 mg/L, and canthaxanthin content reached more than 10 mg/L under conditions
where a higher concentration of nitrogen sources (6%) was employed. It might be advantageous in mass production systems for
these carotenoids to be extracted readily by simply suspending the cells with organic solvents such as acetone and chloroform.
Analyses on the morphological and life history features of the KH105 strain revealed that it belongs to the genus Schizochytrium. This particular species of thraustochytrids is thus considered to be a promising source of xanthophylls as well as DHA for
use in the food industry. 相似文献
8.
Tamada Tsutomu Ueda Yu Kido Ayumu Yoneyama Masami Takeuchi Mitsuru Sanai Hiroyasu Ono Kentaro Yamamoto Akira Sone Teruki 《Magma (New York, N.Y.)》2022,35(4):549-556
Magnetic Resonance Materials in Physics, Biology and Medicine - Image quality (IQ) of diffusion-weighted imaging (DWI) with single-shot echo-planar imaging (ssEPI) suffers from low signal-to-noise... 相似文献
9.
We developed a method of fast probe-to-probe approach for an independently controlled dual-probe scanning tunneling microscope (STM), which is essential to measure the transport property of nanostructures, without scanning electron microscopy (SEM). In the approach method, inchworm motors are used as the coarse positioning devices, which are controlled with a personal computer. The method enables an automatic approach of the probe to the other probe within a short time (typically 30 min). After the approach, a real distance between contact points of each probe tip to a sample can be measured from the overlapped part of the STM images obtained with individual probe. The approach method without SEM is also useful to measure the charge transport in the atmosphere, which will be essential for measurement of the bio molecules. 相似文献
10.
Ranasinghe PD Satoh H Oshiki M Oshima K Suda W Hattori M Mino T 《Water science and technology》2012,66(10):2155-2161
The diversity of bacterial groups in activated sludge from large- and small-scale wastewater treatment plants was explored by barcoded pyrosequencing of 16S rRNA gene. Activated sludge samples (three small and 17 large scale) were collected from 12 wastewater treatment plants to clarify precise taxonomy and relative abundances. DNA was extracted, and amplified by 4 base barcoded 27f/519r primer set. The 454 Titanium (Roche) pyrosequences were obtained and analyses performed by Quantitative Insight Into Microbial Ecology (QIIME) with around 100,000 reads. Sequence statistics were computed, while constructing a phylogenetic tree and heatmap. Computed results explained total microbial diversity at phylum and class level and resolution was further extended to Operational Taxonomic Unit (OTU) based taxonomic assignment for investigating community distribution based on individual sample. Composition of sequence reads were compared and microbial community structures for large- and small-scale treatment plants were identified as major phyla (Proteobacteria and Bacteroidetes) and classes (Betaproteobacteria and Bacteroidetes). Also, family level breakdowns were explained and differences in family Nitrospiraceae and phylum Actinobacteria found at their species level were also illustrated. Thus, the pyrosequencing method provides high resolution insight into microbial community structures in activated sludge that might have been unnoticed with conventional approaches. 相似文献