全文获取类型
收费全文 | 4372篇 |
免费 | 65篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 47篇 |
综合类 | 5篇 |
化学工业 | 1184篇 |
金属工艺 | 66篇 |
机械仪表 | 113篇 |
建筑科学 | 199篇 |
矿业工程 | 8篇 |
能源动力 | 155篇 |
轻工业 | 524篇 |
水利工程 | 26篇 |
石油天然气 | 16篇 |
无线电 | 312篇 |
一般工业技术 | 710篇 |
冶金工业 | 125篇 |
原子能技术 | 45篇 |
自动化技术 | 903篇 |
出版年
2024年 | 48篇 |
2023年 | 48篇 |
2022年 | 184篇 |
2021年 | 218篇 |
2020年 | 118篇 |
2019年 | 125篇 |
2018年 | 151篇 |
2017年 | 136篇 |
2016年 | 196篇 |
2015年 | 117篇 |
2014年 | 168篇 |
2013年 | 300篇 |
2012年 | 274篇 |
2011年 | 328篇 |
2010年 | 216篇 |
2009年 | 242篇 |
2008年 | 228篇 |
2007年 | 182篇 |
2006年 | 192篇 |
2005年 | 149篇 |
2004年 | 109篇 |
2003年 | 96篇 |
2002年 | 77篇 |
2001年 | 60篇 |
2000年 | 58篇 |
1999年 | 55篇 |
1998年 | 41篇 |
1997年 | 34篇 |
1996年 | 35篇 |
1995年 | 42篇 |
1994年 | 24篇 |
1993年 | 25篇 |
1992年 | 10篇 |
1991年 | 17篇 |
1990年 | 12篇 |
1989年 | 11篇 |
1988年 | 7篇 |
1987年 | 7篇 |
1986年 | 8篇 |
1985年 | 9篇 |
1984年 | 10篇 |
1983年 | 6篇 |
1982年 | 16篇 |
1981年 | 11篇 |
1980年 | 5篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1973年 | 3篇 |
排序方式: 共有4438条查询结果,搜索用时 0 毫秒
71.
72.
73.
74.
75.
76.
77.
Haiming Wen Yonghao Zhao Troy D. Topping Dustin Ashford Roberto B. Figueiredo Cheng Xu Terence G. Langdon Enrique J. Lavernia 《Advanced Engineering Materials》2012,14(3):185-194
Pure Cu was processed by ECAP at five different temperatures from room temperature (RT) to 523 K. The influence of pressing temperature on microstructure evolution and tensile behavior was investigated in detail. The results show that as the ECAP temperature is increased the grain size and ductility both increase whereas the dislocation density and yield strength decrease. In the case of ECAP processing in the range of RT to 473 K the mechanism governing microstructural refinement is continuous dynamic recrystallization (CDRX), whereas at 523 K the mechanism changes to discontinuous dynamic recrystallization (DDRX). At higher ECAP temperatures, the kinetics of CDRX are retarded leading to a lower fraction of equiaxed grains/high‐angle grain boundaries and a higher fraction of dislocation cell structures. At 523 K, DDRX induces a high fraction of equiaxed grains with a very low dislocation density which appears responsible for the observed high tensile ductility. The sample processed at 523 K possessed a good combination of strength and ductility, suggesting that processing by ECAP at elevated temperatures may be a suitable alternative to RT ECAP processing followed by subsequent annealing. 相似文献
78.
Wei Xu Roberto B. Figueiredo Xiaolin Wu Simon Pauly Mihai Stoica Jürgen Eckert Terence G. Langdon Kenong Xia 《Advanced Engineering Materials》2011,13(12):1108-1113
A nanocrystalline bcc Ti67.4Nb24.6Zr5Sn3 alloy is shown to fracture in an intrinsically ductile manner with exceptionally large dimples (up to 10 µm) which are two orders of magnitude greater than the grain size (≈ 40 nm). This large plasticity length scale is attributed to a combination of low shear modulus (≈ 27 GPa), high Poisson's ratio (≈ 0.4) and ultrahigh strength (UTS ≈ 1.1 GPa), close to the ideal shear stress, which facilitates ideal shear deformation to promote transgranular shear. 相似文献
79.
Massimiliano Goldwurm;Roberto Radicioni 《法国自动化、信息与运筹学;理论与应用信息》2006,40(2):207-225
In this work we study some probabilistic models for the random generation of words over a given alphabetused in the literature in connection with pattern statistics.Our goal is to compare models based on Markovian processes (where the occurrence of a symbol in a given positiononly depends on a finite number of previous occurrences) and the stochastic models that can generate a word of given length from a regular language under uniform distribution.We present some results that show the differences between these two stochastic models and theirrelationship with the rational probabilistic measures.https://doi.org/10.1051/ita:2006003 相似文献
80.
Rolling Kanban is the name of a kanban management methodology for batch processes manufacturing environment. Proposed in the early 2000s by FESTO Consulting, for two decades we have lost knowledge both from operative and scientific point of view. Basically, Rolling Kanban means a visual planning methodology based on the production of product-families and variants where: (i) set-up times are reduced between the products of the same family, and (ii) relevant times (dozens of minutes if not even hours) must be considered for changeover between products of different families. In addition, the cyclic production sequence between different product families cannot be maintained. Considering that very few technical information and documents are available about this approach, the main objective of this paper is to retrieve and present, for the first time to the scientific community, the Rolling Kanban methodology. Besides, a real industrial implementation concerning a manufacturer of domestic fittings is discussed as a case study. More specifically, two novel versions of the original Rolling Kanban technique are fully presented to effectively overcome certain limits and criticalities found during its operative use, such as the difficulty to realise a pull production, considering increased set-up time for changeover between products of different families. 相似文献