全文获取类型
收费全文 | 1984篇 |
免费 | 42篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 107篇 |
综合类 | 6篇 |
化学工业 | 447篇 |
金属工艺 | 71篇 |
机械仪表 | 41篇 |
建筑科学 | 46篇 |
能源动力 | 74篇 |
轻工业 | 148篇 |
水利工程 | 26篇 |
石油天然气 | 3篇 |
无线电 | 178篇 |
一般工业技术 | 316篇 |
冶金工业 | 399篇 |
原子能技术 | 44篇 |
自动化技术 | 124篇 |
出版年
2023年 | 8篇 |
2022年 | 19篇 |
2021年 | 30篇 |
2020年 | 19篇 |
2019年 | 22篇 |
2018年 | 22篇 |
2017年 | 19篇 |
2016年 | 35篇 |
2015年 | 35篇 |
2014年 | 33篇 |
2013年 | 80篇 |
2012年 | 65篇 |
2011年 | 100篇 |
2010年 | 55篇 |
2009年 | 88篇 |
2008年 | 92篇 |
2007年 | 75篇 |
2006年 | 71篇 |
2005年 | 71篇 |
2004年 | 62篇 |
2003年 | 66篇 |
2002年 | 40篇 |
2001年 | 49篇 |
2000年 | 36篇 |
1999年 | 43篇 |
1998年 | 134篇 |
1997年 | 114篇 |
1996年 | 60篇 |
1995年 | 50篇 |
1994年 | 37篇 |
1993年 | 49篇 |
1992年 | 22篇 |
1991年 | 26篇 |
1990年 | 12篇 |
1989年 | 26篇 |
1988年 | 26篇 |
1987年 | 22篇 |
1986年 | 17篇 |
1985年 | 21篇 |
1984年 | 21篇 |
1983年 | 22篇 |
1982年 | 11篇 |
1981年 | 17篇 |
1980年 | 17篇 |
1979年 | 9篇 |
1978年 | 8篇 |
1977年 | 14篇 |
1976年 | 21篇 |
1973年 | 5篇 |
1972年 | 10篇 |
排序方式: 共有2030条查询结果,搜索用时 15 毫秒
1.
Khutoryan Eduard Kuleshov Alexei Ponomarenko Sergey Lukin Konstantin Tatematsu Yoshinori Tani Masahiko 《Journal of Infrared, Millimeter and Terahertz Waves》2021,42(6):671-683
Journal of Infrared, Millimeter, and Terahertz Waves - Various regimes of hybrid, bulk-surface, modes being excited in the clinotron oscillator with a sheet electron beam and nonuniform grating... 相似文献
2.
Joji Harada 《国际水资源开发杂志》2002,18(4):595-610
This paper discusses environmental conservation in reservoir watersheds, an important aspect relating to dam construction. The discussion of the subject describes how, in response to today's growing awareness of environmental issues, measures to absolutely minimize the effects on the environment of a dam project that will submerge the natural environment should be included in initial project plans, and how special concern for the environment ought to be shown throughout project implementation. Details are explained by introducing examples encountered in Japan. 相似文献
3.
Miao Wang Xinluo Zhao Masato Ohkohchi Yoshinori Ando 《Fullerenes, Nanotubes and Carbon Nanostructures》1996,4(5):1027-1039
Carbon nanotubes prepared by de arc discharge of graphite electrodes in He and CH4 gas took markedly different morphology. Thick nanotubes embellished with many carbon nanoparticles were obtained by evaporation under high CH4 gas pressure and high arc current. Thin and long carbon nanotubes were obtained under a CH4 gas pressure of 50Torr and an arc current of 20A for the anode with a diameter of 6mm. 相似文献
4.
5.
Motofumi Suzuki Kohei Kinoshita Shinji Jomori Hidehiko Harada Kaoru Nakajima Kenji Kimura 《Thin solid films》2007,515(22):8281-8284
The initial stage of iron silicide formation is investigated by high-resolution Rutherford backscattering spectroscopy. During the Fe deposition on Si(001) at 470 °C, the formation of FeSi2 is confirmed by the surface peak analysis. Initially, FeSi2 grows epitaxially so that one of the major crystallographic axes is parallel to the <111> axis of the Si substrate. With increasing Fe deposition, the deviation between the major crystallographic axis of the silicide region and Si<111> increases although the electron diffraction pattern is independent of the amount of Fe deposition. Therefore, the subsurface crystallographic structure of iron silicide is transformed from a cubic-like to a low-symmetry structure. 相似文献
6.
Rinji Akada Yoshirou Shimizu Yuji Matsushita Miho Kawahata Hisashi Hoshida Yoshinori Nishizawa 《Yeast (Chichester, England)》2002,19(1):17-28
Drug-resistance markers for yeast transformation are useful because they can be applied to strains without auxotrophic mutations. However, they are susceptible to technical difficulties, namely lower transformation efficiency and the appearance of drug-resistant mutants without the marker. To avoid these problems, we have constructed a phosphoglycerate kinase (PGK) promoter-driven YAP1 expression cassette, called PGKp-YAP1. Yeast cells containing PGKp-YAP1 were resistant to cycloheximide, a protein synthesis inhibitor, and also to cerulenin, a fatty acid synthesis inhibitor, but not to other drugs tested. The transformation efficiency of PGKp-YAP1 using cerulenin selection was comparable to that using a URA3 auxotrophic marker when low concentrations of cerulenin were used. Non-transformed drug-resistant colonies did appear on the low-concentration cerulenin plates. However, these non-transformed colonies could easily be identified, based on their cycloheximide sensitivity and/or their resistance to aureobasidin A to which the transformants were sensitive. Therefore, the dual drug resistance of PGKp-YAP1 could be used as an effective selection for PGKp-YAP1 recipient cells. The PGKp-YAP1 marker was used to disrupt the LYS2 gene and to transform an industrial yeast strain, indicating that this marker can be used for efficient and reliable gene manipulations in any Saccharomyces cerevisiae strain. 相似文献
7.
Data fitting with a spline using a real-coded genetic algorithm 总被引:2,自引:0,他引:2
Fujiichi Yoshimoto Author Vitae Toshinobu Harada Author Vitae Author Vitae 《Computer aided design》2003,35(8):751-760
To obtain a good approximation for data fitting with a spline, frequently we have to deal with knots as variables. The problem to be solved then becomes a continuous nonlinear and multivariate optimization problem with many local optima. Therefore, it is difficult to obtain the global optimum. In this paper, we propose a method for solving this problem by using a real-coded genetic algorithm. Our method can treat not only data with a smooth underlying function, but also data with an underlying function having discontinuous points and/or cusps. We search for the best model among candidate models by using the Bayes Information Criterion (BIC). With this, we can appropriately determine the number and locations of knots automatically and simultaneously. Five examples of data fitting are given to show the performance of our method. 相似文献
8.
9.
Yoshinori Nakazawa 《Advanced Performance Materials》1995,2(4):369-384
MITI has actively done R&D on industrial technology for waste and reclamation and so there are many research items from small scale to large scale. However, Ecofactory and researches on recycling of metallic materials are introduced here. Ecofactory was proposed by the Mechanical Engineering Laboratory and is now at the stage of the Leading Research, a new research scheme in AISt. Researches on recycling of metallic materials are being done with subsidy. Those researches should contribute to both the preservatin of the global environment and effective recycling of waste materials.Abbreviations AIST
Agency of Industrial Science and Technology
- MITI
Ministry of International Trade and Industry
- NEDO
New Energy and Industrial Technology Development Organization 相似文献
10.
New research and development needs for the drying of ceramics are prooosed. The researches on the ceramic drying are briefly reviewed and the role of the drying in the ceramic production process iS summarized. The drying must deal with molded materials and the problem is of significant difference from another drying with particulate materials. It means that the drying must be performed with keeping the molded feature and the insufficient completion of drying and the careless operation influence directly on the product quality The importnance of the R & D on the heat and moisture transfer. shrinking mechanism. the deformation behavior and the strain-stress formation in the molded clay issuggested. The subjects are also pointed out for the further improvement of the ceramic drying process and the precise design of molding with high quality. 相似文献