全文获取类型
收费全文 | 1405篇 |
免费 | 64篇 |
国内免费 | 20篇 |
专业分类
电工技术 | 70篇 |
综合类 | 1篇 |
化学工业 | 400篇 |
金属工艺 | 45篇 |
机械仪表 | 42篇 |
建筑科学 | 26篇 |
能源动力 | 86篇 |
轻工业 | 87篇 |
水利工程 | 2篇 |
石油天然气 | 1篇 |
无线电 | 101篇 |
一般工业技术 | 287篇 |
冶金工业 | 152篇 |
原子能技术 | 45篇 |
自动化技术 | 144篇 |
出版年
2023年 | 13篇 |
2022年 | 54篇 |
2021年 | 60篇 |
2020年 | 31篇 |
2019年 | 33篇 |
2018年 | 43篇 |
2017年 | 36篇 |
2016年 | 54篇 |
2015年 | 30篇 |
2014年 | 53篇 |
2013年 | 98篇 |
2012年 | 64篇 |
2011年 | 104篇 |
2010年 | 69篇 |
2009年 | 59篇 |
2008年 | 66篇 |
2007年 | 52篇 |
2006年 | 47篇 |
2005年 | 48篇 |
2004年 | 30篇 |
2003年 | 31篇 |
2002年 | 31篇 |
2001年 | 23篇 |
2000年 | 25篇 |
1999年 | 33篇 |
1998年 | 67篇 |
1997年 | 54篇 |
1996年 | 37篇 |
1995年 | 18篇 |
1994年 | 25篇 |
1993年 | 21篇 |
1992年 | 8篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 5篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1980年 | 3篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 7篇 |
1974年 | 2篇 |
1973年 | 3篇 |
1972年 | 2篇 |
1968年 | 1篇 |
排序方式: 共有1489条查询结果,搜索用时 15 毫秒
1.
The World robot summit disaster robotics category – achievements of the 2018 preliminary competition
Satoshi Tadokoro Tetsuya Kimura Masayuki Okugawa Katsuji Oogane Hiroki Igarashi Yoshikazu Ohtsubo 《Advanced Robotics》2019,33(17):854-875
The World Robot Summit is a robot Olympics and aims to be held in a different country every four years from 2020. The concept of the Plant Disaster Prevention challenge is daily inspections, checks, and emergency response in industrial plants, and in this competition, robots must carry out these types of missions in a mock-up plant. The concept of the Tunnel Disaster Response and Recovery challenge is emergency response to tunnel disasters, and is a simulation competition whereby teams compete to show their ability to deal with disasters, by collecting information and removing debris. The Standard Disaster Robotics challenge assesses, in the form of a contest, the standard performance levels of a robot that are necessary for disaster prevention and emergency response. The World Robot Summit Preliminary Competition was held at Tokyo Big Sight in October 2018, and 36 teams participated in the Disaster Robotics Category. UGVs and UAVs contended the merits of new technology for solving complex problems, using core technologies such as mobility, sensing, recognition, performing operations, human interface, autonomous intelligence etc., as well as system integration and implementation of strategies for completing missions, gaining high-level results. 相似文献
2.
There are several damping phenomena in quantum optics. Such phenomena have been usually explained by open systems. In statistical physics, open system dynamics have been used to study the irreversibility and the approach to equilibrium. In this paper, the dynamical change of the mutual entropy for an open system, frequently studied in the quantum optics literature, is rigorously computed through a model of quantum Markov chain. In particular, the concrete formula of Stinespring expression for such a model is obtained and applied to the derivation of the mutual entropy, and some computational results are presented. 相似文献
3.
Hideki Taguchi Yuzuru Takahashi Hiroki Miyamoto 《Journal of the American Ceramic Society》1985,68(10):264-C
Specimens of partially stabilized zirconia were slip cast from aqueous suspensions and sintered at 1500°C for 3 h. The relative density of the cast specimens and the firing shrinkage of the sintered specimens depend on the milling time for the suspension. Vickers hardness and KIC values of 11.46±s0.07 GN/m2 and 6.10 ±0.04 MN.m3/2 , respectively, were obtained for all sintered specimens. The dispersion of the suspension is important in increasing the relative density of the cast specimens. 相似文献
4.
The synthesis of thermal-shock-resistant materials from the system Ta2O5WO3 was investigated. Ta2WO8 had a very low unit-cell thermal expansion coefficient (+0.5 X 10–6° C–1). Ta30W2O81 also had a relatively low coefficient (+4.0 X 10–6 ° C–1) and a thermal durability over 1600° C. The thermal expansion curves of these polycrystalline ceramics were lowered because of microcracks caused by the large thermal expansion anisotropy of the crystal axes and were accompanied by hysteresis loops. The densification of Ta2WO8 ceramic was promoted by the addition of some metal oxides, and the strong ceramic of Ta30W2O81 was obtained by controlling grain growth. 相似文献
5.
Reports design considerations for singlemode interconnectable star couplers which consist of directional couplers. The Letter describes a loss peculiar to this design consideration which arises from the reciprocity of the directional couplers.<> 相似文献
6.
Masako Yudasaka Rie Kikuchi Takeo Matsui Yoshimasa Ohki Mark Baxendale Susumu Yoshimura Etsuro Ota 《Thin solid films》1996,280(1-2):117-123
Thin film formation of graphite by chemical vapor deposition using 2-methyl-1,2′-naphthyl ketone as a starting material was carried out on Ni film substrates. On Ni films directly deposited on quartz glass, the graphite films were obtained when the Ni film thickness was above 1 000 Å and above 5 000 Å at 700 °C and 1 000 °C, respectively. Depositions on thinner Ni film substrates comprise amorphous carbon (a-C) or graphite tubes which was owing to the thermal coagulation of the Ni film into droplets. On the other hand, graphite film was obtained on the Ni film with thickness 10 Å when a-C was inserted between the Ni film and the quartz glass. The coagulation of the Ni film is considered to be avoided by inserting a-C layer. 相似文献
7.
H Ota T Katsuyama S Nakajima H El-Zimaity JG Kim DY Graham RM Genta 《Canadian Metallurgical Quarterly》1998,29(8):846-850
Helicobacter pylori seem to avoid areas of intestinal metaplasia in the gastric mucosa, but attachment of these bacteria to epithelium with the appearance of incomplete intestinal metaplasia has been documented. To characterize the nature of the epithelium to which H pylori was attached, we carried out an immunohistochemical study using monoclonal antibodies against gastric surface mucous cell mucins (M1), blood group-related carbohydrates antigens (Le(a), sialyl Le(a), Le(b), type 1H, and type 2H) and sialyl Tn antigen. The results of this study suggest that these areas of H pylori attachment represent a hybrid epithelium whose cells share characteristics of both gastric surface mucous cells and intestinal metaplastic cells. Whether all areas of incomplete intestinal metaplasia represent an intermediate stage between the normal gastric epithelium and the fully developed complete type of metaplasia remains to be determined. 相似文献
8.
Tetsuya Suemitsu Yoshino K. Fukai Hiroki Sugiyama Kazuo Watanabe Haruki Yokoyama 《Microelectronics Reliability》2002,42(1):47-52
The reliability of InP-based HEMTs is studied, focussing on how it is affected by the doped layer material and gate recess structure. Bias-and-temperature stress tests reveal that fluorine-induced donor passivation in the recess region, formed adjacent to the gate electrode, causes the source resistance (Rs) to increase at large drain bias voltages. The increase in Rs can be prevented by using InP or InAlP as the carrier supply layer material instead of InAlAs. On the other hand, the increase in the drain resistance (Rd) does not depend on the material of the carrier supply layer, which suggests that a mechanism different from that in the case of Rs should be considered. It is also found that a deep gate recess suppresses the increase in Rd after long-term stressing. 相似文献
9.
Y Ota Y Nakano H Yamaguchi K Yoshida T Shirafuji A Adachi 《Canadian Metallurgical Quarterly》1993,20(8):1055-1057
In a 63-year-old male patient with gastric cancer having multiple liver metastases, the metastatic lesions responded well to postoperative staggered intraarterial infusion therapy with MTX and 5-FU. The intraarterial infusion therapy was administered once a week. A total of 5 courses of this therapy produced marked regression of liver metastases and remarkable necrosis. The effect was thus rated as PR. The patient is healthy and has been successfully rehabilitated. His dose is oral 5-FU (200 mg x 2). 相似文献
10.
In the drying of coated films with dispersed pigments, such as floppy disks, the structure of the film is formed during the drying process and depends on the drying condition. It is important to understand the structure formation during drying for the design of the dryer and die better quality of the product. We measured die drying characteristics of the film and determined the structure of dried film experimentally. A qualitative model for the structure formation during drying of the coated film is suggested. 相似文献