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11.
Masuda Takahiro Fujimitsu Kazushige Sumikawa Kosei Kajita Takahiro Tang Yongpeng Hirosawa Shoichi Takizawa Yoichi Yumoto Manabu Otagiri Yoshiharu Horita Zenji 《Metallurgical and Materials Transactions A》2021,52(9):3860-3870
Metallurgical and Materials Transactions A - This study examines strain distribution occurring in the high-pressure sliding (HPS) processing for rods of pure Al and an AZ61 alloy. The strain... 相似文献
12.
In recent years, X-ray CT scanners with task-specific modifications, such as microfocus and/or a synchrotron, have been widely implemented in a variety of fields, including medical and industrial fields. Since microfocus X-ray CT systems enable the visualization of whole samples, and also yield a relatively high resolution of the region of interest in the sample, they are commonly utilized in the fields of soil mechanics and geotechnical engineering. This paper describes a novel loading test apparatus that is specifically designed for microfocus X-ray CT systems capable of performing loading tests to investigate soil behavior during the installation of driven open-section piles. The loading tests were designed to take the micro-level spatial resolution of microfocus X-ray CT systems into account. Digital image correlation (DIC) is subsequently implemented to analyze the obtained CT images, making it possible for measurements to be taken of the displacement fields in the ground following installation of the model pile. Finally, the versatility of this novel test apparatus is proof of its high potential for application in different types of loading tests. 相似文献
13.
Approximate method of estimating seismic performance of high‐rise buildings with oil‐dampers 下载免费PDF全文
When subjected to long‐period ground motions, many existing high‐rise buildings constructed on plains with soft, deep sediment layers experience severe lateral deflection, caused by the resonance between the long‐period natural frequency of the building and the long‐period ground motions, even if they are far from the epicenter. This was the case for a number of buildings in Tokyo, Nagoya, and Osaka affected by the ground motions produced by the 2011 off the Pacific coast of Tohoku earthquake in Japan. Oil‐dampers are commonly used to improve the seismic performance of existing high‐rise buildings subjected to long‐period ground motion. This paper proposes a simple but accurate analytical method of predicting the seismic performance of high‐rise buildings retrofitted with oil‐dampers installed inside and/or outside of the frames. The method extends the authors' previous one‐dimensional theory to a more general method that is applicable to buildings with internal and external oil‐dampers installed in an arbitrary story. The accuracy of the proposed method is demonstrated through numerical calculations using a model of a high‐rise building with and without internal and external oil‐dampers. The proposed method is effective in the preliminary stages of improving the seismic performance of high‐rise buildings. 相似文献
14.
This study aims to evaluate the performance of ozone treatment for removing N-nitrosamines from reverse osmosis (RO) concentrate in water recycling applications. In the absence of any N-nitrosamine precursors, the destruction efficiency of N-nitrosamines was dependent on their molecular weight or the length of the alkyl chain in their molecular structure. Experiments conducted with RO concentrate showed that ozonation could lead to the formation of N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA), resulting in an increase in concentrations of these N-nitrosamines. Nevertheless, ozonation was effective for destruction of N-nitrosamines with molecular weight greater than that of NDEA (102 g/mol). 相似文献
15.
Akihito Sagara Takahiro NomuraMasakatsu Tsubota Noriyuki OkinakaTomohiro Akiyama 《Materials Chemistry and Physics》2014
This paper describes the control of the melting point and improvement of the thermal endurance of D-mannitol (melting point Tm = 440 K) as a phase-change material (PCM) by vacuum impregnation of the PCM into nanosized pores of porous SiO2 grains. First, we examined the effects of the average pore size (DP) of porous SiO2 on Tm and latent heat (L) of PCM/SiO2 composites. Second, we investigated the thermal endurance of the composites using constant temperature kinetics based on L of the PCM and composites. Third, we performed cyclic tests of melting and freezing on the composite to evaluate leakage of the PCM. Thermophysical properties of the samples were measured by differential scanning calorimetry, and the following results were obtained: (1) The impregnation ratio of the composites was 0.91–0.99; therefore, almost all pores were completely filled with the PCM. (2) Tm shifted to lower temperature with smaller DP, reaching 413 K in case of the PCM/SiO2 composite with a DP of 11.6 nm (3) Tm was derived as a function of DP from the Gibbs–Thomson equation taking into account the existence of a nonfreezing layer on the surface of the pore wall. (4) The duration of thermal degradation of the PCM/SiO2 composite with DP = 11.6 nm was three times longer than that of the pure PCM at a temperature that is 10 K more than each melting point. (5) The PCM/SiO2 composite with DP = 11.6 nm can use as a shape-stable PCM composite without leakage of PCM. 相似文献
16.
Yoshitomo Isomae Takahiro Ishinabe Yosei Shibata Hideo Fujikake 《Journal of the Society for Information Display》2019,27(4):251-258
We achieved uniform liquid crystal (LC) alignment in lattice‐shaped dielectric walls 1 μm in pitch; this is a prerequisite when driving the individual pixels of spatial light modulators, facilitating the development of practical electronic holographic displays with a wide field of view. In lattice‐shaped dielectric walls, LC alignment becomes unstable, particularly on the bottom and the walls; the LC directors tend to align parallel to the walls. To overcome this problem, we created lattice‐shaped walls featuring partition plates that allow uniform LC alignment. When the plates confine LCs to small regions exhibiting spatial anisotropy, the LC elastic effect and wall anchoring forces align the LC directors parallel to the long anisotropic axis. We found that pixels 0.5 μm × 1.0 μm in pitch formed if the partition plates were sufficiently thick to allow shielding of electric field leakage. 相似文献
17.
Reo Etani Takahiro Kataoka Yuichi Nishiyama Yuji Takata 《Journal of Nuclear Science and Technology》2013,50(12):1512-1518
It has been reported that radon inhalation activates antioxidative functions in liver and has an antioxidative effect against hepatopathy similar to that of the antioxidative effects of ascorbic acid (VC) or α-tocopherol (VE). In this study, we examined the combined effects of radon inhalation and antioxidant vitamin administration on acute alcohol-induced hepatopathy in mice. ICR mice were subjected to intraperitoneal (i.p.) administration of alcohol after pretreating with air only (sham) or radon at a concentration of approximately 2000 Bq/m3 for 24 hours and i.p. administration of VC (300 mg/kg body weight) or VE (300 mg/kg body weight). In mice injected with alcohol, the combined radon and antioxidant vitamins treatment significantly decreased the activities of glutamic oxaloacetic transaminase in serum compared to not only the alcohol-administered group (sham group), but also the radon inhalation with alcohol administration group or the vitamin and alcohol administration group. In addition, radon inhalation significantly increased the antioxidant level, in such as the catalase activity and the total glutathione content in liver compared to the sham group. These results suggested that the combined radon and antioxidant vitamin treatment could effectively inhibit alcohol-induced hepatopathy in mice without any antagonizing action. 相似文献
18.
Mohammad Abul Hossain Shahidul Islam Farzana A. Chowdhury Tariq G. Mohiuddin Koji Uchida Takahiro Tamura 《Fullerenes, Nanotubes and Carbon Nanostructures》2016,24(1):43-51
We studied the elemental analysis, structural morphology, mechanical, and electrical properties of carbon nanoparticles synthesized from diesel. The spherical carbon particle size in the range of about 10 to 80 nm in diameter was observed in scanning electron microscope (SEM) studies that were identified by Atomic force microscopy (AFM) study as an aggregation of carbon particles of average size 2.5 nm. The surface rms of carbon nanoparticle thin film (CNTF) was measured directly by AFM and found 0.22 nm. The Derjaguin–Muller–Toporov (DMT) elastic modulus of carbon nanoparticles (CNPs) was measured by PeakForce QNM mode of AFM. The minimum and maximum elastic modulus was measured of 0.40 GPa and 43.89 GPa, respectively. The resistivity, conductivity, magneto resistance, mobility, and average Hall co-efficient were measured by “Ecopia Hall-effect measurement system” by four-point Van der Pauw approach at ambient condition. We demonstrated I–V characteristic at the Indium/CNTF thin film interface, which is accompanied by rectifying behavior. 相似文献
19.
20.
Meng Guo Masakoto Kanezashi Hiroki Nagasawa Liang Yu Kazuki Yamamoto Takahiro Gunji Toshinori Tsuru 《American Institute of Chemical Engineers》2020,66(4):e16850
Fine-tuned, molecular-composite, organosilica membranes were fabricated via the co-condensation of organosilica precursors bis(triethoxysilyl)acetylene (BTESA) and bis(triethoxysilyl)benzene (BTESB). Fourier transform infrared and UV–vis spectra confirmed the co-condensation behaviors of BTESA and BTESB. The evolution of the network structure indicated that the incorporated BTESB decreased the membrane pore size, which was determined by a modified gas translation model according to the steric effect of the phenyl groups. The incorporation of BTESB to BTESA finely tuned the membrane structure and endowed the resultant composite membrane with improved separation properties. The BTESAB 9:1 membrane (molar ratio of BTESA/BTESB was 9:1) exhibited high C3H6 permeance at 4.5 × 10−8 mol m−2 s−1 Pa−1 and a C3H6/C3H8 permeance ratio of 33 at 50°C. One of the most important developments of this study involved clearly defining the relationship between membrane pore size and C3H6/C3H8 separation performance for organosilica membranes in single and binary separation systems. 相似文献