全文获取类型
收费全文 | 271篇 |
免费 | 10篇 |
专业分类
电工技术 | 27篇 |
化学工业 | 62篇 |
金属工艺 | 7篇 |
机械仪表 | 5篇 |
建筑科学 | 10篇 |
矿业工程 | 2篇 |
能源动力 | 9篇 |
轻工业 | 22篇 |
无线电 | 9篇 |
一般工业技术 | 43篇 |
冶金工业 | 53篇 |
原子能技术 | 3篇 |
自动化技术 | 29篇 |
出版年
2023年 | 1篇 |
2022年 | 5篇 |
2021年 | 7篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 11篇 |
2015年 | 8篇 |
2014年 | 7篇 |
2013年 | 13篇 |
2012年 | 11篇 |
2011年 | 11篇 |
2010年 | 4篇 |
2009年 | 11篇 |
2008年 | 11篇 |
2007年 | 17篇 |
2006年 | 13篇 |
2005年 | 7篇 |
2004年 | 12篇 |
2003年 | 8篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 1篇 |
1999年 | 5篇 |
1998年 | 23篇 |
1997年 | 10篇 |
1996年 | 9篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 1篇 |
排序方式: 共有281条查询结果,搜索用时 765 毫秒
31.
Sung-Jun Park Feel-Soon Kang Su Eog Cho Chae-Joo Moon Hae-Kon Nam Toshifumi Ise 《Solar Energy》2006,80(5):524-534
This paper proposes a modified converter for use in photovoltaic system. In the modified converter, the voltage ratio of output to input is equal to that of the general boost converter. The difference between the two converters is the configuration of output terminal. Therefore, the working voltage of an output capacitor and the value of its capacitance can be lower than those of the general boost converter. This paper also presents an efficient parallel driving scheme to increase output power and to reduce the output voltage ripple. The parallel driving method using the modified converter and current mode control gives a good solution for alleviating the current sharing unbalance problem. It reduces the output voltage ripple by increasing the equivalent switching frequency of the modified converter. The performance of the proposed converter system is verified through computer-aided simulations and experimental results. 相似文献
32.
Xiangdong Tao Ran Zhang Zhengguo Gao Toshifumi Satoh Toyoji Kakuchi Qian Duan 《Journal of Materials Science》2011,46(19):6396-6401
Poly(N-isopropylacrylamide) with aromatic end groups (Ar-PNIPAM) were synthesized by atom transfer radical polymerization of N-isopropylacrylamide in isopropanol using phenyl 2-chloropropionate, (4′-phenyl)phenyl 2-chloropropionate, and (2′,6′-diphenyl)phenyl
2-chloropropionate as initiators and CuCl/tris(2-dimethylaminoethyl)amine (Me6TREN) as a catalytic system. The resulting polymers had narrow polydispersity index of 1.10–1.14 and molecular weights of
3700–4600 g mol−1. Then, novel functional complexes of Ar-PNIPAM, Europium(III) (Eu(III)), and α-Thenoyltrifluoroacetone (TTA) (Ar-PNIPAM/Eu(III)/TTA)
with thermosensitive and fluorescent properties were synthesized and characterized by Fourier transform infrared spectra and
fluorescence spectroscopy. Metal Eu(III) was not only bonded to oxygen and nitrogen atoms of polymer chain in PNIPAM, but
also bonded to TTA. The maximum emission intensity of the complexes at 613 nm was enhanced about 22, 27, 33 times compared
with that of the corresponding Eu(III). The lower critical solution temperatures (LCSTs) of Ar-PNIPAM/Eu(III)/TTA were slightly
greater compared with that of PNIPAM. Eu(III) complexes had excellent fluorescence performance, the fluorescence spectrum
presented characteristic emission of Eu(III) at 613 nm. 相似文献
33.
Y Kasano H Tanimura H Yamaue M Hayashido Y Umano 《Canadian Metallurgical Quarterly》1996,91(11):2418-2420
Hepatic actinomycosis is a rare infectious disease caused by an anaerobic gram-positive bacterium of the genus Actinomyces. Herein, we describe an unusual case of hepatic actinomycosis involving the diaphragm and right lung. A 41-yr-old man was admitted to Wakayama Medical School Hospital presenting with right back pain and cough. Computed tomography and magnetic resonance image revealed a 5 x 10 cm tumor in the anterior superior segment of the liver, which extended to the diaphragm and right lung. Angiography demonstrated a hypervascular tumor and the enlarged right inferior phrenic artery feeding around the tumor. The patient underwent a hepatectomy with partial resections of the diaphragm and the right middle pulmonary lobe. Microscopically, the specimen showed sulfur granules and was positive for Gram stain and Grocott stain and negative for Ziehl-Neelsen stain. These findings were consistent with actinomycosis of the liver. His postoperative course was uneventful and no recurrence was observed 1 yr postoperatively. Although there are at least 36 well-documented cases until 1993, no other report has been found infiltrating the diaphragm and lung. 相似文献
34.
A voltage sag compensating using a micro‐SMES is presented. Based on previous works, we have carried out experiments for voltage sag compensation on the laboratory‐built system in order to validate the proposed minimum energy injection voltage sag compensation algorithm. To improve the compensating performance of the system, two‐degree‐of‐freedom voltage control is proposed. In this paper, the circuit configuration and feedback voltage control system of the compensator are described and the experimental results are reported. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(2): 84–92, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10267 相似文献
35.
Eiichi Tamiya Yoko Sugiura Toshifumi Takeuchi Masayasu Suzuki Isao Karube Akitane Akiyama 《Sensors and actuators. B, Chemical》1993,10(3):179-184
An integrated ultra micro glutamate sensor has been constructed with a 7 μm diameter platinized carbon-fiber disk (PCD) electrode and a platinum thin-film (PTF) counter electrode fabricated on the glass capillary tube. By platinization, the electrode activity of the carbon fiber is improved. In order to obtain a stable response, a pulse potential is applied for hydrogen peroxide measurement. The PTF counter electrode shows good stability and can be used as a substitute for a silver-silver chloride electrode. Since the integrated PCD electrode shows good characteristics as a hydrogen peroxide sensor, glutamate oxidase is immobilized onto the tip of the PCD electrode to construct the ultra micro glutamate sensor. The sensor shows stable response to glutamate and a response time within 12 s. The calibration range for glutamate measurement is 50–800 μM. 相似文献
36.
37.
M Yamamoto T Yamada K Yoshihira A Tanimura I Tomita 《Food Additives & Contaminants》1988,5(3):289-298
The effects of food components and food additives on the formation of nitrosamides were studied. Citrate accelerated nitrosamide formation from nitrite and various precursors, such as ureas, urethanes, guanidines and amides. The accelerating effects of citrate on the formation of methylurea and ethylenethiourea were larger at higher pH values. The formation of most nitrosamides was not accelerated by thiocyanate, which is known to catalyze the formation of nitrosamines. Compounds having carboxyl groups tended to accelerate the nitrosation of methylurea. Nitrosation of methylurea was inhibited by thiols, polyphenols, alcohols, sorbic acid, dl-alpha-tocopherol etc., due to possibly competition for available nitrite. 相似文献
38.
Pathogenic effect of the crystalline exotoxine of Bacillus thuringiensis on the larvae of fleas was investigated. Deformities and changes in the functions of organs and tissues caused by the exotoxin in larvae and imago developed from the latter result in the premature death of the individuals (to 100%) or in the sterility of the remaining fleas. 相似文献
39.
Toshifumi Ohkubo Kenji Tanaka Terunao Hirota Hiroshi Hosaka Kiyoshi Itao Yoko Shinohara Hideo Maeda Kenji Kato Yasuyuki Mitsuoka Kunio Nakajima 《Microsystem Technologies》2005,11(8-10):1094-1101
Advances in the digital network society require both higher density and higher transfer rates in all sorts of storage systems. Especially in optical recording, the trend toward higher density and larger capacity requires novel surface-recording technologies that can drastically diminish head-to-medium spacing, resulting in an improvement in spatial resolution and, finally, a higher recording density. To this end, we have already proposed a novel contact optical head slider that is able to almost cancel the suspension load by generating hydrodynamic pressure, thus realizing a lower net contact force. Evaluating the dynamic contact force is requisite in realizing its stable sliding operation and higher signal readout performance. In this study, a continuous acoustic emission (AE) signal was utilized to detect the dynamic contact force. AE signal modulation was compared with the applied out-of-plane acceleration on a medium generated by a spindle combined piezo-electric actuator. It was clarified that the detected AE modulation amplitude was approximately proportional to the applied acceleration, and that utilizing AE modulation will be a useful method for evaluating dynamic contact force. 相似文献
40.