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排序方式: 共有319条查询结果,搜索用时 14 毫秒
31.
Yasuhiro Tomita Mituhiro Nakamura Kimio Niwa 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1988,270(2-3):403-410
In order to study the local response of silicon strip detectors, we have developed a local charge generator using near-infrared ligh emitting diode. The edge properties of the strip detectors were studied precisely with this tool. In the case of our tested detector, the lateral extension of the depletion area was measured to be about 120 μm at a bias voltage of 40 V. 相似文献
32.
Akio Ueda Dai Kato Tomoyuki Kamata Hiroshi Uetsuka Shigeru Hirono Osamu Niwa 《Carbon》2009,47(8):1943-7599
We fabricated electrochemically stable fluorinated nano-carbon film that had an sp2 and sp3 hybrid nanocrystalline structure formed using the electron cyclotron resonance (ECR) sputtering method. This fluorinated ECR (F-ECR) nano-carbon film prepared with a short CF4 plasma treatment has a high fluorine content (F/C:0.20) and a low oxygen content (O/C:0.02) on its surface and retains its original morphology. This F-ECR nano-carbon is capable of a lower capacitance current, and a wider potential window than untreated ECR nano-carbon. The electron transfer rates at an F-ECR electrode are as high as those of untreated carbons for , whereas they are much slower than those of untreated ECR nano-carbon for Fe2+/3+ and owing to its selective sp2 fluorination. These slow electron transfer rates for Fe2+/3+ and are maintained during potential cycles due to its robust nanocrystalline structure. In contrast, these slow electron transfer rates were easily recovered for fluorinated glassy carbon under same condition. Furthermore, a smaller fluorination effect was observed for polycrystalline boron-doped diamond owing to the low reactivity of its sp3 bonds. Our ECR nano-carbon film is suitable for the effective fabrication of a fluorinated surface while maintaining a relatively active electrochemical interface and excellent stability. 相似文献
33.
Tauer A Bender TO Fleischmann EH Niwa T Jörres A Pischetsrieder M 《Molecular nutrition & food research》2005,49(7):710-715
Conventional fluids for peritoneal dialysis (PD) contain reactive glucose degradation products (GDPs) as a result of glucose breakdown during heat-sterilization. GDPs in PD fluids (PDFs) have been associated with the progressive alteration of the peritoneal membrane during long-term PD by cytotoxic effects and formation of advanced glycation endproducts (AGEs). In this study, we investigated the possible fate of two characteristic GDPs, 3-deoxyglucosone (3-DG) and glyoxal, during PD. In vivo, 3-DG and glyoxal concentrations, which were analyzed by high-performance liquid chromatography (HPLC), decreased in PDFs by 78% and 88% during 4 h of dwell time. The PDFs were then incubated in vitro in the presence of the most important reaction partners of GDPs in the peritoneal cavity. Neither human peritoneal mesothelial cells, human peritoneal fibroblasts, soluble protein, an insoluble collagen surface, nor components of spent dialysate led to a significant reduction of 3-DG or glyoxal after 6 h. Only after long-term incubation, a noticeable decrease of 3-DG was observed (-37% after three weeks), more likely due to spontaneous degradation reaction than formation of advanced glycation endproducts. These results suggest that in the course of PD, 3-DG, and glyoxal are absorbed into the organism and thus might contribute to the systemic pool of reactive carbonyl compounds. 相似文献
34.
Theories of the biaxial tensile properties, the uniaxial tensile properties, and the shear-deformation properties of plain-weave fabrics are presented in a general form, a simplified stereo-model of the structure of plain-weave fabrics being used throughout these theories. In the first part of this series, the biaxial tensile-deformation theory is presented with the aid of the model, and the forces required to stretch the fabric along the warp and weft directions at the same time are theoretically calculated from the properties of yarns and from the structure of the fabrics. In this biaxial theory, both warp and weft yarns are assumed to be perfectly flexible, and the forces caused by yarn-bending are ignored. The compressibility of the yarn under the action of a lateral compressive force is also introduced into the theory, and it is shown that the compressive properties of yarns have a great influence on the tensile properties of the fabrics. 相似文献
35.
36.
Wool fibres are subjected to severe mechanical actions during the worsted-spinning process, especially on a high-speed system. The loss of crimp and crimp recovery of single wool fibres are examined by measuring the crimp shrinkage of single fibres and the bulkiness of fibre bundles sampled at various stages in a commonly used worsted-spinning system. It is found that the crimp and crimp recovery of single fibres gradually decrease with progress through the spinning system, the reduction being particularly noticeable during carding. Fibre bundles with a high crimp level showed greater bulkiness. 相似文献
37.
The attachment of peptides to the surface of spherical dendrimers via graft polymerization is described here (see Figure). It is shown that the resulting peptide dendrimers display greatly enhanced helicity compared to non‐dendrimer‐based analogues. This effect is attributed to aggregation of peptide segments on the dendrimer surface. 相似文献
38.
The computerisation of procedures can address not only the way procedures are presented or displayed, but also how they are generated and maintained. The computerisation of procedure generation will result in an improved basis for procedure display, and also make it possible to maintain the procedures on the level of internal representation rather than on the level of display. This paper describes a project, which focused on developing a system for computerised procedure generation (CPG) based on the principles of cognitive systems engineering. The CPG system was integrated with an already existing system for computerised procedure presentation, and enhanced with a number of other functions to produce a system for integrated computerisation of operating procedures. 相似文献
39.
40.
S Ohta M Niwa M Nozaki M Hattori H Shimonaka S Dohi 《Canadian Metallurgical Quarterly》1995,44(11):1452-1457
Morphine is well known to produce tolerance and dependence. The mechanisms for these phenomena are not clearly understood and there are a number of conflicting reports that chronic morphine administration decreases, increases, or leaves unchanged the number of opioid binding sites. We examined the potency of MScontin (oral controlled-release preparation of morphine) to induce morphine dependence and also determined the change of mu, delta and kappa opioid receptor types in brain homogenates obtained from morphine-dependent guinea-pigs. 1. Guinea-pigs were implanted subcutaneously with MScontin (300 mg.kg-1) and naloxone was employed to precipitate jumping behavior of withdrawal symptoms at various times. The highest degree of physical dependence was observed on the 2nd day after implantation. Therefore, this period was chosen to investigate opioid receptor binding assay. 2. Two days after implantation, the binding of 3H-DAGO (mu agonist), 3H-DPDPE (delta agonist) and 3H-U69593 (kappa agonist) to brain membranes prepared from morphine dependent and control guinea-pigs was determined. Scatchard plot of the saturation binding data revealed an increase in Bmax values (maximum specific binding) and no change in the Kd values (equilibrium dissociation constants) of 3H-opioid ligand bindings obtained from morphine-dependent animals as compared to controls. These results indicate that brain mu, delta and kappa opioid receptors are up-regulated in morphine dependent guinea-pigs. 相似文献