全文获取类型
收费全文 | 208篇 |
免费 | 0篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 15篇 |
化学工业 | 21篇 |
机械仪表 | 8篇 |
建筑科学 | 1篇 |
能源动力 | 4篇 |
轻工业 | 19篇 |
无线电 | 32篇 |
一般工业技术 | 29篇 |
冶金工业 | 71篇 |
原子能技术 | 3篇 |
自动化技术 | 9篇 |
出版年
2022年 | 3篇 |
2021年 | 4篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2015年 | 4篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 5篇 |
2011年 | 7篇 |
2010年 | 4篇 |
2009年 | 8篇 |
2008年 | 14篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 6篇 |
2004年 | 2篇 |
2003年 | 8篇 |
2002年 | 4篇 |
2001年 | 7篇 |
2000年 | 8篇 |
1999年 | 3篇 |
1998年 | 32篇 |
1997年 | 21篇 |
1996年 | 9篇 |
1995年 | 4篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 6篇 |
1983年 | 2篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1975年 | 3篇 |
排序方式: 共有212条查询结果,搜索用时 15 毫秒
1.
2.
H. Ohyama K. Takakura H. Matsuoka T. Jono E. Simoen C. Claeys J. Uemura T. Kishikawa 《Journal of Materials Science: Materials in Electronics》2003,14(5-7):437-440
Results are presented of a detailed study of the effects of high-temperature 4-MeV neutron irradiation on the performance degradation of Si pin photodiodes together with the radiation-induced defects, observed by deep level transient spectroscopy (DLTS). It was found that the dark current increases after irradiation, while the photocurrent decreases. After irradiation, two majority electron capture levels with (E
c–0.22 eV) and (E
c–0.40 eV) were induced in the n-Si substrate, while one minority hole capture level with (E
v+0.37 eV) was found. Additionally, the degradation of the device performance and the introduction rate of the lattice defects decreases with increasing irradiation temperature. For a 250 °C irradiation, the reduction of the reverse current is only 20% of the starting value. This result suggests that the creation and recovery of the radiation damage proceeds simultaneously at high temperatures. 相似文献
3.
Yasuhiko H. Mori Takehiro Nosoko Atsushi Mikami Tetsuya Ohyama 《Chemical Engineering Communications》1990,92(1):95-102
The shape of interfaces formed by the contact of two liquid phases, immiscible with each other, and a gaseous phase can be predicted on the condition that the tension to work at each interface is known with a sufficient accuracy. In general, interfacial tension data available are not so accurate, however, as to be useful as they are in predicting the shape of interfaces, particularly when the spreading coefficient of either liquid (liquid 1) on the other (liquid 2) has a negative value of a small magnitude. Presented in this note is a simple method to rectify the interfacial tension data, with the aid of a measurement of the radius of a lens of liquid 1 of a known volume placed on the horizontal surface of liquid 2, and thereby make them usable for predicting interfacial geometries. The method is tested by applying it to benzene/water and n-pentane/water systems. 相似文献
4.
重复控制系统中非周期扰动的抑制 总被引:3,自引:0,他引:3
为了改善重复控制系统中的扰动抑制性能,提出一种基于曲率模型的扰动估计新方法.该方法的主要特点是扰动的估计值直接与重复控制规则结合也不影响重复控制系统的稳定性.仿真结果显示该方法可以有效地抑制扰动. 相似文献
5.
An advanced coded imaging system is described, and some results of phantom experiments are presented. The advanced method uses a pair of coherent codes (+ 1 and -1 codes) and has many advantages compared with conventional ones. One of the greatest advantages is that there are no sidelobes in the focal plane and only a few in other planes. Therefore, when an object can be regarded as two-dimensional, it is perfectly reconstructed with high detecting efficiency, and this is successfully simulated by a thyroid phantom with 99mTc. Moreover, this system has an ability to reconstruct tomograms, which is also shown by using ring phantoms piled on one another with some cold spots in their shells. From these experimental results it may be concluded that the new system is useful for practical applications, for example, to nuclear medicine. 相似文献
6.
Comparative analysis of experimental performance and stability of sensorless induction motor drives 总被引:1,自引:0,他引:1
This paper compares the experimental performance of three flux and speed observers for speed-sensorless induction motor drives and discusses the cause of their differences. The small signal analysis using the linearized model is carried out to analyze stability. Three methods are generally accepted to be representative candidates for high sensorless performance, namely: 1) rotor-flux model reference adaptive system (MRAS); 2) torque-current MRAS; and 3) adaptive nonlinear flux observer. Many other sensorless methods improved these methods. The paper discusses baseline conditions for the experiments and the stability analysis, which include matched load inertia, specified speed estimator dynamics, and sensorless operation within a speed control loop. For the comparison tests in the paper, the speed estimation dynamics of the methods are the same; this is important for parameter sensitivity. The paper concentrates on the low-speed performance, and all results shown are under sensorless speed control. 相似文献
7.
H. Ohyama K. Takakura T. Watanabe K. Nishiyama K. Shigaki T. Kudou M. Nakabayashi S. Kuboyama S. Matsuda C. Kamezawa E. Simoen C. Claey 《Journal of Materials Science: Materials in Electronics》2005,16(7):455-458
The impact of radiation damage on the device performance of 4H-SiC Schottky diodes, which are irradiated at room temperature with 2-MeV electrons is studied. After irradiation the reverse current increases, while the forward current and the capacitance decrease with barrier height and carrier density. The decrease of the barrier height is mainly responsible for the increase of the reverse current, while the decrease of the forward current for a high fluence is caused by the increase of the resistance in the bulk of the crystal. Although no electron capture levels are observed before irradiation, three electron capture levels (E1, E2, and E3) are induced after irradiation. It is noted that the decrease in carrier density is partly caused by the contribution of non-observed electron capture level in the DLT spectrum, which compensates the free carriers. 相似文献
8.
M. Ohyama 《材料科学技术学报》1997,13(4):299-301
The structure, electrical transport, and optical properties of GaSe films fabricated by means of radio-frequency (RF) magnetron sputtering in Ar were investigated. The as-sputtered GaSe films were amorphous, and their optical energy gap Eg are 1.9~2.6 eV. The effect of the synthesis conditions on the optical and electrical properties of the GaSe films has also been studied 相似文献
9.
Y. Ukai T. Ohyama L. Fennell Y. Kato M. Paukshto P. Smith O. Yamashita S. Nakanishi 《Journal of the Society for Information Display》2005,13(1):17-24
Abstract— A thin‐crystalline‐film (TCF) polarizer has been developed which can be used internally in liquid‐crystal‐display cells. Based on this material, a manufacturing process has been developed for the fabrication of monochrome LCDs with internal polarizers. A new TCF polarizer material and coating equipment, developed to realize a high‐performance color TFT‐LCD, are discussed. 相似文献
10.
S Tomono S Kawazu T Utsugi T Ohno N Katto Y Ohyama T Uchiyama R Nagai 《Canadian Metallurgical Quarterly》1998,35(3):25-28
Caught between the successes of modern psychopharmacology, the requests of suffering patients for quick relief, and the shortsightedness of many third-party payers, psychodynamic psychotherapy might seem to be on the ropes. It is, however, thriving and providing crucial help to many individuals for whom medication and brief counseling are insufficient. Meanwhile, many more who could benefit from psychotherapy do not have an opportunity to do so. Although psychodynamic psychotherapy originated and developed within a medical framework, it has minimal visibility on the current medical scene, and many physicians have been provided with little meaningful information about it. This article is intended to give physicians a general idea of what psychodynamic psychotherapy is and how it works. 相似文献