全文获取类型
收费全文 | 1831篇 |
免费 | 58篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 65篇 |
综合类 | 2篇 |
化学工业 | 464篇 |
金属工艺 | 41篇 |
机械仪表 | 49篇 |
建筑科学 | 30篇 |
矿业工程 | 1篇 |
能源动力 | 68篇 |
轻工业 | 82篇 |
水利工程 | 5篇 |
石油天然气 | 2篇 |
无线电 | 176篇 |
一般工业技术 | 353篇 |
冶金工业 | 321篇 |
原子能技术 | 50篇 |
自动化技术 | 183篇 |
出版年
2023年 | 26篇 |
2022年 | 37篇 |
2021年 | 64篇 |
2020年 | 31篇 |
2019年 | 38篇 |
2018年 | 39篇 |
2017年 | 51篇 |
2016年 | 50篇 |
2015年 | 39篇 |
2014年 | 56篇 |
2013年 | 124篇 |
2012年 | 82篇 |
2011年 | 112篇 |
2010年 | 96篇 |
2009年 | 99篇 |
2008年 | 70篇 |
2007年 | 72篇 |
2006年 | 69篇 |
2005年 | 46篇 |
2004年 | 39篇 |
2003年 | 38篇 |
2002年 | 20篇 |
2001年 | 23篇 |
2000年 | 25篇 |
1999年 | 27篇 |
1998年 | 116篇 |
1997年 | 64篇 |
1996年 | 50篇 |
1995年 | 33篇 |
1994年 | 32篇 |
1993年 | 32篇 |
1992年 | 22篇 |
1991年 | 15篇 |
1990年 | 10篇 |
1989年 | 16篇 |
1988年 | 14篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 11篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 13篇 |
1981年 | 8篇 |
1980年 | 9篇 |
1979年 | 9篇 |
1977年 | 9篇 |
1976年 | 11篇 |
1974年 | 4篇 |
1971年 | 4篇 |
1970年 | 4篇 |
排序方式: 共有1892条查询结果,搜索用时 0 毫秒
171.
Kei Masaki Yusuke K. Shibama Shinji Sakurai Masahiro Katayama Akira Sakasai 《Fusion Engineering and Design》2011,86(9-11):1872-1876
JT-60 is planned to be upgraded to JT-60SA tokamak machine with fully superconducting coils, which is a project of the JA-EU satellite tokamak program under both Broader Approach program and Japanese domestic program. The JT-60SA vacuum vessel (VV) has a D-shape poloidal cross section and a toroidal configuration with 10° facet segmented in toroidal direction. The material of the VV is 316L stainless steel with low cobalt content of <0.05 wt%. A double wall structure is adopted for the VV to ensure high rigidity and high toroidal one-turn resistance simultaneously.Fundamental welding R&D and a trial manufacturing of the 20° upper half of the VV have been performed to study the manufacturing procedure. After the confirmation of the quality of the mock-up, manufacturing of the actual VV started in November 2009. 相似文献
172.
Shiro Asano Toshihisa Okuyama Toshiwo Oonawa Yutaka Yanagi Mitsuru Ejiri Toshio Kanahara Koji Ichihashi Atsushi Kikuchi Shoichi Mizumaki Kei Masaki Yusuke K. Shibama Masahiro Katayama Akira Sakasai 《Fusion Engineering and Design》2011,86(9-11):1816-1820
The real vacuum vessel (VV) manufacturing of JT-60SA has started since November 2009 at Toshiba. Prior to starting manufacturing, fundamental welding R&Ds had been performed by three stages. In the first stage, primary tests for screening welding method were performed. In the second stage, the trial welding for 1 m-long straight and curved double shell samples were conducted. The dependences of welding quality and distortion on the welding conditions, such as arc voltage and current, setting accuracy, welding sequence, and the shape of grooves were studied. In addition, welding condition with low heat input was explored. In the last stage, fabrication sequence was confirmed and established by the trial manufacturing of the 20° upper half mock-up [1]. This paper presents the R&D results obtained in the first and second stages. 相似文献
173.
Cuiling Li Bo Jiang Hungru Chen Masataka Imura Liwen Sang Victor Malgras Yoshio Bando Tansir Ahamad Saad M. Alshehri Satoshi Tominaka Yusuke Yamauchi 《Nano Research》2016,9(6):1752-1762
Mesoporous Au films consisting of a network of interconnected Au ligaments around ultra-large pores were found to exhibit a promising electrocatalytic activity towards sluggish reactions. Mesoporous Au films with pore sizes up to 25 nm were successfully fabricated using a polymeric micelle approach. A superior catalytic activity of the mesoporous Au films towards methanol oxidation was confirmed, which was thoroughly analyzed and compared with that of other Au materials. An intrinsic investigation on the high catalytic activity revealed that the superior performance of the as-prepared mesoporous Au film was related to its unique atomic structures around the mesopores with well-crystallized facets and several step/kink sites on the Au surfaces. These findings showcase a strategic and feasible design for preparing highly active Au-based catalysts that could be used as promising candidates in electrocatalytic applications. 相似文献
174.
CNT-PyC-SiC/SiC double-layer coatings were prepared by growth of CNTs on C/C followed by pyrolytic carbon deposition and SiC deposition. The microstructure and the oxidation behavior of the coatings were investigated. With increasing PyC amount in the coating, the coating showed fewer cracks and a higher oxidation resistance and thermal shock resistance. CNT-PyC played a role in improving the bonding strength between C/C and coatings, alleviating stress in SiC coating and decreasing the cracks. 相似文献
175.
Hiroshi Abe Yusuke Imai Takefumi Goto Yukihiro Yoshimura Masami Aono Takahiro Takekiyo Hitoshi Matsumoto Takashi Arai 《Metallurgical and Materials Transactions A》2010,41(5):1137-1143
Crystal structures of room-temperature ionic liquid (RTIL)-H2O mixtures are determined by the X-ray diffraction method. The RTIL is N,N-diethyl-N-methyl-N-2-methoxyethyl ammonium tetrafluoroborate, [DEME][BF4]. At 0.9 mol pct H2O, two kinds of superstructures occur simultaneously without a strain. Also, the volume of the unit cell is very small only
at 0.9 mol pct additives. This relates to the composite domain structure, including a twin-related one, as an elastic anomaly.
At other water concentrations, such an extraordinary behavior is not observable. By assuming a sublattice having an equivalent
lattice constant, a water network at 1 mol pct H2O is simulated using a Monte Carlo (MC) method. The network develops over the medium range in the simulation box. 相似文献
176.
Iida M. Kuroda N. Otsuka H. Hirose M. Yamasaki Y. Ohta K. Shimakawa K. Nakabayashi T. Yamauchi H. Sano T. Gyohten T. Maruta M. Yamazaki A. Morishita F. Dosaka K. Takeuchi M. Arimoto K. 《Solid-State Circuits, IEEE Journal of》2005,40(11):2296-2304
A 16 Mb embedded DRAM macro in a fully CMOS logic compatible 90 nm process with a low noise core architecture and a high-accuracy post-fabrication tuning scheme has been developed. Based on the proposed techniques, 61% improvement of the sensing accuracy is realized. Even with the smallest 5 fF/cell capacitance, a 322 MHz random-cycle access while 32 ms data retention time which contributes to save the data retention power down to 60 /spl mu/W are achieved. 相似文献
177.
Hiroshige Matsuoka Koji Oka Yusuke Yamashita Fumihiro Saeki Shigehisa Fukui 《Microsystem Technologies》2011,17(5-7):983-990
Thermocapillary deformations of an ultra-thin liquid film caused by temperature distribution were three-dimensionally analyzed using the unsteady and linearized long wave equation considering the temperature and film thickness dependence of surface tension. The temperature and film thickness dependence equation for the surface tension of a liquid was firstly established. The temperature dependence of the surface tension was obtained experimentally using a surface tensiometer and the film thickness dependence was obtained theoretically from the corrected van der Waals pressure equation for a symmetric multilayer system. Time evolutions of depression and groove of the ultra-thin liquid film caused by local heating were obtained quantitatively. 相似文献
178.
Takahiro Kataoka Reo Etani Norie Kanzaki Kaori Sasaoka Yusuke Kobashi Katsumi Hanamoto 《Journal of Nuclear Science and Technology》2016,53(11):1681-1685
In this study, we compared the protective effects of radon inhalation and ascorbic acid administration on transient global cerebral ischemic injury in gerbils. Gerbils were treated with radon inhalation (2000 Bq/m3, 24 hours) or ascorbic acid (100, 300, or 500 mg/kg body weight). Then, transient global cerebral ischemia was induced by bilateral occlusion of the common carotid artery. Results showed that the number of damaged neurons was significantly increased in gerbils that underwent ischemia compared with that in control gerbils. However, the number of damaged neurons in gerbils treated with radon or 500 mg/kg of ascorbic acid before ischemia was significantly lower than gerbils who were subjected to ischemia without any pretreatment, and the protective effects of radon inhalation were similar to the effects of administering 500 mg/kg ascorbic acid. The levels of superoxide dismutase (SOD) and total glutathione (t-GSH) in brain tissue were increased to a similar extent by pretreatment with radon inhalation or 500 mg/kg of ascorbic acid. These findings suggested that radon inhalation has a protective antioxidative effect against transient global cerebral ischemic injury similar to 500 mg/kg ascorbic acid treatment. 相似文献
179.
A highly accelerated humidity test for plastic encapsulated IC reliability short-term evaluation has been studied. 2-Vessel pressure cooker test (PCT) equipment capable of controlling relative humidity and temperature independently, and of keeping specimens free from water droplet condensation, has been designed. This equipment consists of a test chamber and a vapor chamber. Humidity conditions are set by controlling the temperature difference between the test chamber and the vapor chamber. Humidity levels are controlled with the direct pressure adjustment. The whole test chamber is heated in an oven, thereby obtaining temperature stability and uniformity. Using this equipment, humidity tests were carried out on plastic molded ICs. As a result, good test reproducibility and excellent correlation in test results between PCT and conventional humidity test such as 85°C/85%RH, were obtained. As a consequence, it was found possible, in a short time, to evaluate plastic molded IC reliability quantitatively in humidity ambients using this 2-vessel PCT equipment. This equipment can be used for quality assurance testing of plastic-encapsulated ICs in a short time. 相似文献
180.
The effect of humidity during storage on the crosslinking reactions of isocyanate groups was investigated with attenuated total reflectance Fourier transform infrared spectroscopy with pressure‐sensitive adhesives composed of poly[ethyl acrylate‐co‐(2‐ethylhexyl acrylate)‐co‐(2‐hydroxyethyl methacrylate)] as a base resin and polyisocyanate as a crosslinker. A peak‐resolving analysis of the amide II region revealed four bands. According to an analysis of the Fourier transform infrared spectra of the model compounds, these four bands were assigned to free urethane linkages, hydrogen‐bonded urethane linkages, free urea linkages, and hydrogen‐bonded urea linkages. As expected, storage under humid conditions led to the formation of free and hydrogen‐bonded urea linkages corresponding to the promotion of isocyanate consumption. Peak resolution of the amide II region was found to be a reasonable way of monitoring urethane and urea linkages during crosslinking reactions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3039–3045, 2003 相似文献