全文获取类型
收费全文 | 654篇 |
免费 | 43篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 192篇 |
金属工艺 | 10篇 |
机械仪表 | 27篇 |
建筑科学 | 15篇 |
矿业工程 | 1篇 |
能源动力 | 23篇 |
轻工业 | 87篇 |
水利工程 | 3篇 |
石油天然气 | 3篇 |
无线电 | 35篇 |
一般工业技术 | 76篇 |
冶金工业 | 135篇 |
原子能技术 | 17篇 |
自动化技术 | 71篇 |
出版年
2023年 | 3篇 |
2022年 | 13篇 |
2021年 | 17篇 |
2020年 | 13篇 |
2019年 | 16篇 |
2018年 | 21篇 |
2017年 | 23篇 |
2016年 | 15篇 |
2015年 | 18篇 |
2014年 | 22篇 |
2013年 | 40篇 |
2012年 | 32篇 |
2011年 | 44篇 |
2010年 | 24篇 |
2009年 | 31篇 |
2008年 | 36篇 |
2007年 | 22篇 |
2006年 | 26篇 |
2005年 | 13篇 |
2004年 | 19篇 |
2003年 | 20篇 |
2002年 | 21篇 |
2001年 | 11篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1998年 | 49篇 |
1997年 | 29篇 |
1996年 | 20篇 |
1995年 | 17篇 |
1994年 | 5篇 |
1993年 | 7篇 |
1992年 | 3篇 |
1991年 | 1篇 |
1990年 | 6篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1976年 | 10篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有697条查询结果,搜索用时 31 毫秒
121.
The objective of the present work is to predict the formation of chevron crack in copper wire drawing process. The first part of this paper is to determine the chevron crack formation initiated by a central burst inside the wire material using experimental tests. These results are compared with results from a series of numerical simulations using the Cockcroft?CLatham fracture criterion. The second part of this work concerns the determination of a curve that divides the chevron and safe zones for a better wire drawing process. The conditions of central burst defects formation along the wire axis depend on drawing parameters and friction coefficient between the die and the wire. The friction coefficient is defined as a linear function of temperature rise which is measured close to the wire-die interface. The obtained results show that the friction coefficient depending on temperature rise during wire drawing has an impact on the damage of copper wire. 相似文献
122.
J. Nieto G. de Arcas M. Ruiz J. Vega J.M. López E. Barrera R. Castro N. Utzel P. Makijarvi L. Zabeo 《Fusion Engineering and Design》2012,87(12):2152-2155
EURATOM/CIEMAT and the Technical University of Madrid UPM are involved in the development of a FPSC (fast plant system control) prototype for ITER based on PXIe form factor. The FPSC architecture includes a GPU-based real time high performance computing service which has been integrated under EPICS (experimental physics and industrial control system). In this work we present the design of this service and its performance evaluation with respect to other solutions based in multi-core processors. Plasma pre-processing algorithms, illustrative of the type of tasks that could be required for both control and diagnostics, are used during the performance evaluation. 相似文献
123.
The Logistic‐Exponential Weibull Model as a Tool to Predict Natural Microflora Inactivation of Agave Mapsiaga Aguamiel (Agave Sap) by High Pressure Treatments
下载免费PDF全文
![点击此处可从《Journal of Food Processing and Preservation》网站下载免费的PDF全文](/ch/ext_images/free.gif)
124.
125.
126.
Effects of drying methods on quality attributes of murta (ugni molinae turcz) berries: bioactivity,nutritional aspects,texture profile,microstructure and functional properties
下载免费PDF全文
![点击此处可从《Journal of food process engineering》网站下载免费的PDF全文](/ch/ext_images/free.gif)
127.
128.
I. Lupelli A. Murari P. Gaudio M. Gelfusa D. Mazon J. Vega 《Fusion Engineering and Design》2013,88(6-8):738-741
The development of computationally efficient model selection strategies represents an important problem facing the analysis of nuclear fusion experimental data, in particular in the field of scaling laws for the extrapolation to future machines, and image processing. In this paper, a new model selection indicator, named Model Falsification Criterion (MFC), will be presented and applied to the problem of choosing the most generalizable scaling laws for the power threshold (PThresh) to access the H-mode of confinement in tokamaks. The proposed indicator is based on the properties of the model residuals, their entropy and an implementation of the data falsification principle. The model selection ability of the proposed criterion will be demonstrated in comparison with the most widely used frequentist (Akaike information criterion) and bayesian (Bayesian information criterion) indicators. 相似文献
129.
Josefa Mula Francisco Campuzano-Bolarin Manuel Díaz-Madroñero Katerine M. Carpio 《国际生产研究杂志》2013,51(13):4087-4104
This article proposes a simulation approach based on system dynamics for operational procurement and transport planning in a two-level, multi-product and multi-period supply chain. This work uses the Vensim® simulation tool to highlight the potential of system dynamics for supply chain simulation. A real continuous simulation application is presented in an automobile supply chain. The effectiveness of the proposed model is validated through the comparison of the results provided by spreadsheet-based simulation, fuzzy multi-objective programming and system dynamics-based simulation models. The fundamental point of this paper is that the simulation model is the most effective approach in quantifying the trade-off between number of truck shipments and average inventory level. In this case, the number of truck shipments is to be minimised, resulting in a higher inventory level. If the average inventory level were minimised, then there would be more truck shipments. Here, it is shown the benefit of this type of simulation model in reducing inventory by about 10%. 相似文献
130.
Vega Orozco A Daneri C Anesetti G Cabrera R Sosa Z Rastrilla AM 《Reproduction (Cambridge, England)》2012,143(2):183-193
Oestradiol (E(2)) is a key hormone in the regulation of reproductive processes. The aims of this work were a) to examine the distributions of oestrogen receptor α (ERα) and ERβ in the neurons of the superior mesenteric ganglion (SMG) in the oestrus stage by immunohistochemistry, b) to demonstrate whether E(2) in the SMG modifies progesterone (P(4)), androstenedione (A(2)) and nitrite release in the ovarian compartment on oestrus day and c) to demonstrate whether E(2) in the ganglion modifies the activity and gene expression in the ovary of the steroidogenic enzymes 3β-hydroxysteroid dehydrogenase (3β-HSD) and 20α-hydroxysteroid dehydrogenase (20α-HSD). The ex vivo SMG-ovarian nervous plexus-ovary system was used. E(2), tamoxifen (Txf) and E(2) plus Txf were added in the ganglion to measure ovarian P(4) release, while E(2) alone was added to measure ovarian A(2) and nitrites release. Immunohistochemistry revealed cytoplasmic ERα immunoreactivity only in the neural somas in the SMG. E(2) increased ovarian P(4) and A(2) release at 15, 30 and 60?min but decreased nitrites. The activity and gene expression of 3β-HSD increased, while the activity and gene expression of 20α-HSD did not show changes with respect to the control. Txf in the ganglion diminished P(4) release only at 60?min. E(2) plus Txf in the ganglion reverted the effect of E(2) alone and the inhibitory effect of Txf. The results of this study demonstrate that ERα activation in the SMG has an impact on ovarian steroidogenesis in rats, thus providing evidence for the critical role of peripheral system neurons in the control of ovarian functions under normal and pathological conditions. 相似文献