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排序方式: 共有333条查询结果,搜索用时 19 毫秒
1.
Akiko Suzuki Mina Minamide Chihiro Iwaya Kenichi Ogata Junichi Iwata 《International journal of molecular sciences》2020,21(23)
Carbohydrates, fats, and proteins are the underlying energy sources for animals and are catabolized through specific biochemical cascades involving numerous enzymes. The catabolites and metabolites in these metabolic pathways are crucial for many cellular functions; therefore, an imbalance and/or dysregulation of these pathways causes cellular dysfunction, resulting in various metabolic diseases. Bone, a highly mineralized organ that serves as a skeleton of the body, undergoes continuous active turnover, which is required for the maintenance of healthy bony components through the deposition and resorption of bone matrix and minerals. This highly coordinated event is regulated throughout life by bone cells such as osteoblasts, osteoclasts, and osteocytes, and requires synchronized activities from different metabolic pathways. Here, we aim to provide a comprehensive review of the cellular metabolism involved in bone development and homeostasis, as revealed by mouse genetic studies. 相似文献
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新日本钢铁公司高强度汽车用钢板的开发 总被引:2,自引:0,他引:2
在对汽车提高燃料利用率、节能和提高冲撞安全性的要求日益强烈的情况下,不增加车体重量而提高安全性的方法之一,就是使用高强度钢板.钢板高强度化带来的最大问题就是钢板加工性能变差.为适应用户的要求,新日铁已经开发出各种高强度钢板.本文对适应于汽车不同部位的、具有良好成形性的各种高强钢板的特点及冲撞吸收能、疲劳强度等特性进行了介绍. 相似文献
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Takashi MINAMI Shohei ARAI Naoki KENMOCHI Hiroaki YASHIRO Chihiro TAKAHASHI Shinji KOBAYASHI Tohru MIZUUCHI Shinsuke OHSHIMA Satoshi YAMAMOTO Hiroyuki OKADA Kazunobu NAGASAKI Yuji NAKAMURA Kiyoshi HANATANI Shigeru KONOSHIMA Fumimichi SANO 《等离子体科学和技术》2013,(3):240-243
A new high repetition rate Nd:YAG Thomson scattering system is developed for the Heliotron J helical device.A main purpose of installing the new system is the temporal evolution measurement of a plasma profile for improved confinement physics such as the edge transport barrier (H-mode) or the internal transport barrier of the helical plasma.The system has 25 spatial points with ~10mm resolution.Two high repetition Nd:YAG lasers (>550mJ@ 50Hz) realize the measurement of the time evolution of the plasma profile with ~10ms time intervals.Scattered light is collected by a large concave mirror (D=800 mm,f/2.25) with a solid angle of ~100 mstr and transferred to interference filter polychromators by optical fiber bundles in a staircase form.The signal is amplified by newly designed fast preamplifiers with DC and AC output,which reduces the low frequency background noise.The signals are digitized with a multi-event QDC,fast gated integrators.The data acquisition is performed by a VME-based system operated by the CINOS. 相似文献
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AKESHI TAKAHASHI TOSHIAKI TANAKA HIROYUKI FUJITA YUKI HIRANUMA SATOSHI ICHIMURA KAZUHIRO WATANABE MIEKO KASHIWAGI TETSUYA MAEJIMA 《Electrical Engineering in Japan》2018,204(3):41-52
This paper presents the development results of a ?1 MV dc filter and dc measurement systems for an ITER (International Thermonuclear Experimental Reactor) neutral beam injector (NBI) system. High accuracy of 0.5% and fast responsivity of 3.3 μs, ?3 dB are required for the dc measurement systems: both dc voltage dividers and DCCTs. Circuit design and thermal flow design were carried out to clarify and minimize their effects on the accuracy and responsivity. The validity of the established design was demonstrated by the actual‐product tests; temperature rise of each components fell below the allowable value; inner components of dc filter withstood dc ?1.2 MV; each voltage divider accurately measured the voltage during the dc ?1.2 MV withstand voltage test; the voltage dividers and the DCCTs were adequate to the requirements of responsivity (3.3 μs, ?3 dB). 相似文献
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ERI MARUYAMA AKESHI TAKAHASHI SHINICHI WAKUI Wataru Hatsune 《Electrical Engineering in Japan》2016,194(3):51-58
Carrier harmonic losses that consist of iron loss, eddy current loss, and ac copper loss are produced in a permanent magnet machine driven by a PWM inverter. It is already known that a higher motor inductance can lead to lower carrier harmonic losses. This paper investigates the carrier harmonic loss composition of two motors with identical dimensions but different inductances. The results of finite element analysis (FEA) showed that the eddy current loss in the iron core accounts for most of the carrier harmonic loss. It is also shown that the carrier harmonic loss of the iron core is quantifiable using theoretical calculations. 相似文献
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Chihiro Iwamoto 《Metallurgical and Materials Transactions A》2014,45(3):1371-1375
An Al/glass joint created by using ultrasonic welding was analyzed by means of multiscale observation techniques. A cross-sectional analysis of the microstructure revealed that a directly joined interface without reaction phases formed at the periphery of a round joined region. The size of Al grains markedly decreased after ultrasonic welding and some subgrains were observed along the interface. The finer Al grains observed around the periphery of the joined interface showed active plastic flow that promoted welding. 相似文献
10.
In this study, we apply the finite element method to investigate precursor to frictional sliding phenomena arising immediately prior to macroscopic stick–slip transitions in elastic bodies within the framework of a continuum theory. Using a numerical model that mimics an actual experimental system, we study the behavior of contact surface nodes to assess the influence of stiffness, driving velocity, initial conditions, and discretization conditions on the propagation characteristics of microscopic slips. In particular, we show that the initial distribution of frictional stress arising due to the Poisson effect has a significant effect on the propagation characteristics in slip regions. Next, based on the results of a finite element analysis of precursor phenomena that accounts for the influence of bulk compliance, we consider the determination of parameters in rate-dependent friction models. With regard to the behavior of sliding friction, we show that the relationship between friction tests and friction models is fundamentally different from the relationship between material tests and constitutive models for material deformation. We conclude that a proper understanding and classification of friction tests, friction models, and the relationship between these tests and boundary value problems are crucial ingredients in the application of computer-aided engineering techniques to sliding-friction phenomena; indeed, friction tests must ultimately be treated as boundary value problems. 相似文献