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101.
In the current design practices of steel-strip reinforced earth walls (SSREWs), the length of the reinforcing material is determined based on the equilibrium between the reinforcement tension and the earth pressure acting on the wall. Here, the resistance of the reinforcing material laid in the active failure zone (AFZ) is not considered. Moreover, the mechanical role of the reinforcing material against the integrity of the SSREW has not been sufficiently verified. Regarding the seismic stability of SSREW, although it is investigated by treating the entire reinforced earth wall as a rigid body, this inspection method is for gravity-retaining walls, and the difference in the seismic behavior between the SSREW and the rigid body is not clear. In this study, therefore, dynamic centrifuge model tests on 6 types of SSREWs were conducted to clarify the following items: (1) the basic earthquake behavior of a SSREW, (2) the mechanical role of the reinforcing material laid in the AFZ and (3) the mechanical role of the reinforcing material against the integrity of the SSREW. The results indicated that the reinforcing material laid in the AFZ can restrain the amount of deformation of the wall during earthquakes. Furthermore, the more stable the AFZ is, the smaller the maximum wall displacement will be. 相似文献
102.
Hosoya M. Hioe W. Casas J. Kamikawai R. Harada Y. Wada Y. Nakane H. Suda R. Goto E. 《Applied Superconductivity, IEEE Transactions on》1991,1(2):77-89
A quantum flux parametron (QFP), a single quantum flux superconductive device that has a potential of up to 100-GHz switching with nW-order power dissipation, is considered. The potential of the QFP and key technologies when QFPs are applied to a Josephson supercomputer are described. Switching speed, stability, and power dissipation of a QFP are discussed. QFP gates, circuits, and systems are next described. Then, ultra-fast clock distribution using a standing wave is explained. High-speed operation at more than 10 GHz and 1014 error-free operations per QFP have been demonstrated. Finally described is a high-density packaging scheme by three-dimensional integration, which is very important for ultra-high speed circuits because the propagation delay becomes dominant in such circuits 相似文献
103.
Kaname Kanai Takahiro Miyazaki Takanori Wakita Kouki Akaike Takayoshi Yokoya Yukio Ouchi Kazuhiko Seki 《Advanced functional materials》2010,20(13):2046-2052
How annealing influences the morphology of a highly regioregular poly(3‐hexylthiophene) (RR‐P3HT) film at the substrate interface as well as the lateral inhomogeneity in the electronic structure of the film are elucidated. Whereas previous studies have reported that high‐molecular‐weight (MW) RR‐P3HT films tend to show low crystallinity even after annealing, it is found that high‐MW RR‐P3HT does show high crystallinity after annealing at high temperature for a long time. Photoemission electron microscopy (PEEM), X‐ray photoemission spectroscopy, and ultraviolet photoemission spectroscopy results clearly resolve a considerable lateral inhomogeneity in the morphology of RR‐P3HT film, which results in a variation of the electronic structure depending on the local crystallinity. The PEEM results show how annealing facilitates crystal growth in a high‐MW RR‐P3HT film. 相似文献
104.
Lingping Kong Jue Gong Qingyang Hu Francesco Capitani Anna Celeste Takanori Hattori Asami Sano-Furukawa Nana Li Wenge Yang Gang Liu Ho-kwang Mao 《Advanced functional materials》2021,31(9):2009131
The soft nature of organic–inorganic halide perovskites renders their lattice particularly tunable to external stimuli such as pressure, undoubtedly offering an effective way to modify their structure for extraordinary optoelectronic properties. Here, using the methylammonium lead iodide as a representative exploratory platform, it is observed that the pressure-driven lattice disorder can be significantly suppressed via hydrogen isotope effect, which is crucial for better optical and mechanical properties previously unattainable. By a comprehensive in situ neutron/synchrotron-based analysis and optical characterizations, a remarkable photoluminescence (PL) enhancement by threefold is convinced in deuterated CD3ND3PbI3, which also shows much greater structural robustness with retainable PL after high peak-pressure compression–decompression cycle. With the first-principles calculations, an atomic level understanding of the strong correlation among the organic sublattice and lead iodide octahedral framework and structural photonics is proposed, where the less dynamic CD3ND3+ cations are vital to maintain the long-range crystalline order through steric and Coulombic interactions. These results also show that CD3ND3PbI3-based solar cell has comparable photovoltaic performance as CH3NH3PbI3-based device but exhibits considerably slower degradation behavior, thus representing a paradigm by suggesting isotope-functionalized perovskite materials for better materials-by-design and more stable photovoltaic application. 相似文献
105.
A Kawakami K Eguchi N Matsuoka M Tsuboi T Koji S Urayama K Fujiyama T Kiriyama T Nakashima PK Nakane S Nagataki 《Canadian Metallurgical Quarterly》1997,12(10):1637-1646
We investigated the cellular and humoral interactions between peripheral blood mononuclear cells (PBMCs) and human osteoblasts, leading to apoptosis of osteoblasts. Human osteoblastic cell line MG63 and human primary osteoblast-like cells obtained from biopsy specimens were used in this study. PBMCs were isolated from healthy donors and cultured with or without stimulation by recombinant interleukin-2 followed by 12-o-tetradecanoylphorbol 13-acetate with ionomycin. Fas was functionally expressed on MG63 and primary osteoblast-like cells. Activated PBMCs expressed Fas ligand (FasL) strongly on their surface and killed MG63 and primary osteoblast-like cells. Cultured supernatants of activated PBMCs also induced apoptotic cell death of MG63 and primary osteoblast-like cells. In contrast, both unstimulated PBMCs and cultured supernatants of unstimulated PBMCs did not induce apoptosis of these cells. Furthermore, the cytotoxic effect and induction of apoptosis against MG63 and primary osteoblast-like cells by activated PBMCs and cultured supernatants were inhibited significantly by human Fas chimeric protein. Our data showed that human osteoblasts expressed Fas fuctionally and both membrane-type and soluble form FasL from activated PBMCs induced apoptosis of these cells, providing the one possible mechanism of bone loss in inflammatory diseases such as rheumatoid arthritis. 相似文献
106.
K Deguchi N Yokota M Koguchi Y Suzuki S Fukayama R Ishihara S Oda S Tanaka Y Nakane T Fukumoto 《Canadian Metallurgical Quarterly》1994,47(9):1160-1185
In order to evaluate antimicrobial activity of ciprofloxacin (CPFX), minimum inhibitory concentrations (MICs) of CPFX and other drugs were determined against clinical isolates that were obtained in our laboratory from January to December of 1991, and of 1993. The results are summarized as follows: 1. CPFX-resistant strains were on the increase in various strains, compared to those in the early 1980s. However, many of CPFX-resistant strains were multi-drug resistant including beta-lactams. In addition, they showed cross resistance to other fluoroquinolone agents. 2. MIC distribution of other drugs suggested that there were increased frequencies of benzylpenicillin (PCG)-insensitive Streptococcus pneumoniae (PISP) and CEPs-resistant Escherichia coli. However, MIC distribution of CPFX to these resistant strains were in a relatively low range. 3. When isolates of 1991 were compared to those of 1993, we confirmed that CPFX-resistant strains decreased among certain bacteria such as Staphylococcus aureus. Also we confirmed that fewer CPFX-resistant strains were found among bacteria that may be highly related to infections encountered in daily medical care. 相似文献
107.
The initiation of microcracks at MsS inclusions and their coalescence during fracture toughness tests of ASTM A533B steel
compact tension specimens were detected by an acoustic emission technique. The sources of emission, which are characterized
by the crack size and orientation, fracture mode, and time history, are represented by a time-dependent moment tensor. Since
the recorded waveforms are related to the moment tensor, the Green’s displacement functions of the specimen, and the transfer
function of the recording system by a convolution integral in the theory of elastodynamics, the moment tensors are determined
by techniques of deconvolution. Two types of sources were found: a tensile mode of crack caused by decohesion of MnS inclusion
and the coalescence of microcracks with mixed tensile and shear modes. The dimensions and time durations of microcracks were
also estimated in this study.
T{upakanori} O{uphira}, Late Associate Professor of the Department of Metallurgy and Materials Science, University of Tokyo,
Tokyo, Japan, died on December 9, 1987, at the age of 33 years. He had been a Visiting Scientist at Cornell University from
1984 through 1986 under the sponsorship of the Japan Society for the promotion of Science. 相似文献
108.
Y Ishida K Todaka I Kuwahara H Hashiguchi Y Ishizuka H Nakane Y Mitsuyama 《Canadian Metallurgical Quarterly》1998,253(1):45-48
The CD4 receptor of T-helper cells is an essential participant in immune response formation and HIV infection. We report here that the extracellular domains of CD4 receptor can catalyze the phosphotransferase (kinase) reaction. Incubation of rsCD4 in solution with [gamma-32P]ATP results in the Ca2+-dependent autophosphorylation of the protein presumably at a His residue because the reaction is prevented by the diethylpyrocarbonate treatment. The rsCD4 phosphorylates milk casein or human plasma proteins as a Ser/Thr protein kinase. 相似文献
109.
K Asayama K Hayashi H Hayashibe N Uchida T Nakane K Kodera S Nakazawa 《Canadian Metallurgical Quarterly》1998,22(12):1209-1216
OBJECTIVE: To determine the clinical utility of a new age-adjusted measure of body fat distribution (based on waist and hip circumferences) and stature, in relation to biochemical complications in obese children. DESIGN: Cross-sectional, clinical study. The formula to calculate the common standard deviation score (SDS) of waist-to-hip ratio/height (WHR/Ht) was obtained from the data of control children. The relationship between WHR/Ht SDS, as the age-adjusted measure, in obese children and their clinical laboratory data was evaluated. SUBJECTS: Outpatient obese Japanese children (102 boys and 75 girls) and control children (508 boys and 549 girls), ranging in age from 6-15 y. MEASUREMENTS: Height, body weight, waist girth, hip girth, triceps and subscapular skinfold thicknesses, as anthropometric measures. Percent overweight, percent body fat, waist girth, WHR and WHR/Ht SDS as criteria for obesity. Clinical laboratory analyses for fasting blood samples of obese children. RESULTS: The WHR/Ht SDS closely correlated with age in obese children, thus reflecting the progress of abdominal obesity during growth. The obese boys were more hyperlipidaemic than the girls were, although the percent overweight was similar in both genders. The percent overweight, percent body fat, waist girth and WHR/Ht SDS all correlated well with triglyceride (TG), alanine aminotransferase (ALT) and insulin in boys, whereas only waist girth and WHR/Ht SDS showed a close correlation with TG and insulin in girls. The obese subjects were subdivided according to the number of abnormal values observed in TG, ALT and insulin. For obese boys, all five indices of obesity were higher in the groups with complications than in the group without. In the girls, only the WHR/Ht SDS constantly differed between subgroups. WHR/Ht SDS most obviously distinguished the groups with complications from the other group with a wide margin of difference (2-fold in boys and > 2-fold in girls) in the mean values. CONCLUSION: The WHR/Ht SDS can serve as an index predicting the occurrence of biochemical complications in obese children ranging from the age of 6-15 y. 相似文献
110.
Nonaka Y. Nakane H. Hasuike K. Maeda T. 《IEEE transactions on instrumentation and measurement》1992,41(6):1010-1013
The SRPM (simultaneous resistivity and permeability measurement) method, which simultaneously estimates the electrical and magnetic properties of a rod-shaped sample conductor, has been studied. In the SRPM method, the theoretical and measured values of the difference in the complex impedance of a solenoid coil with and without the sample are used. To estimate the resistivity of a short-length sample, the difference in the complex impedance was calculated by the method of weighted residual (MWR), as the difference calculated by the former SRPM method was valid only for a longer sample. The resistivity of copper samples of various lengths was estimated by the SRPM method, and their ratios to those measured by the DC four-probe method were obtained. The ratio was less than 1.3% when the ratio of the length of the sample conductor to the length of the solenoid coil was larger than 1 and less than 3.1% when the length ratio was less than 1 相似文献