全文获取类型
收费全文 | 1056篇 |
免费 | 50篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 17篇 |
综合类 | 36篇 |
化学工业 | 247篇 |
金属工艺 | 24篇 |
机械仪表 | 10篇 |
建筑科学 | 110篇 |
矿业工程 | 4篇 |
能源动力 | 40篇 |
轻工业 | 125篇 |
水利工程 | 3篇 |
无线电 | 55篇 |
一般工业技术 | 185篇 |
冶金工业 | 64篇 |
原子能技术 | 2篇 |
自动化技术 | 186篇 |
出版年
2023年 | 12篇 |
2022年 | 22篇 |
2021年 | 34篇 |
2020年 | 31篇 |
2019年 | 22篇 |
2018年 | 20篇 |
2017年 | 23篇 |
2016年 | 47篇 |
2015年 | 30篇 |
2014年 | 44篇 |
2013年 | 61篇 |
2012年 | 42篇 |
2011年 | 79篇 |
2010年 | 69篇 |
2009年 | 59篇 |
2008年 | 67篇 |
2007年 | 64篇 |
2006年 | 62篇 |
2005年 | 55篇 |
2004年 | 30篇 |
2003年 | 30篇 |
2002年 | 21篇 |
2001年 | 22篇 |
2000年 | 12篇 |
1999年 | 26篇 |
1998年 | 12篇 |
1997年 | 16篇 |
1996年 | 9篇 |
1995年 | 6篇 |
1994年 | 7篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 11篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1971年 | 3篇 |
1966年 | 3篇 |
1965年 | 1篇 |
排序方式: 共有1108条查询结果,搜索用时 15 毫秒
141.
142.
Marc Serra Colomer Birgitte Funch Natalia Solodovnikova Timothy John Hobley Jochen Förster 《Journal of the Institute of Brewing》2020,126(3):280-288
Several hop derived compounds in wort are known to be converted by yeast during fermentation, influencing the overall perception of the beer. A deeper understanding of such metabolic processes during fermentation is needed to achieve better control of the outcome. Here, the interaction between hop derived compounds and the yeast genera Brettanomyces was studied. Several Brettanomyces strains with different genomic backgrounds were selected, focusing on two traits: beta-glucosidase activity and nitrate assimilation. The role of three beta-glucosidases present in Brettanomyces bruxellensis and Brettanomyces anomalus and their impact on the final monoterpene alcohol profile was analysed. The beta-glucosidase activity was highly strain dependent, with B. anomalus CRL-49 exhibiting the highest conversion. Such activity could not be related to the release of aglycones from hops during fermentation, as a substantial part of such activity was intracellular. Nevertheless, the reduction of geraniol to β-citronellol was remarkably efficient for all Brettanomyces strains during fermentation, and it is suggested that two oxidoreductases BbHye2 and BbHye3 may have an influence. Moreover, the transfer of nitrate from hops to wort and its further assimilation by Brettanomyces species was analysed. The amount of nitrate in wort proved to be linearly proportional to the contact time of the hops with the wort. The level of nitrate assimilation by yeast was shown to be dependent on the nitrate assimilation cluster (YNR, YNI, YNT). Hence, the desired yeast strains may be selected according to the genetic make-up. © 2020 The Authors. Journal of the Institute of Brewing published by John Wiley & Sons Ltd on behalf of The Institute of Brewing & Distilling 相似文献
143.
144.
145.
A diffusion-based kinetic model for resin-based ion exchange is proposed that simultaneously describes extra- and intraparticle diffusion for the purpose of predicting batch transient adsorption rates during resin operation. The extraparticle diffusion is simulated through Newton's-law-of-cooling assuming a stagnant laminar layer, while the intraparticle simulation assumes a homogeneous internal pore environment and uses the Nernst–Planck equation to describe multi-ion diffusion. The key parameters of the model are the mass transfer coefficient, the intrinsic diffusivities of the adsorbing and desorbing ions and the equilibrium coefficient associated with the Mass-Action-Law, which is assumed to be applicable at the liquid/resin interface. A novel method is described to determine the critically important ion concentration at the interface from experiment. Kinetic tests are undertaken in a closed circuit system, adsorbing Na, Mg, and Ba ions separately onto gel type acid resin, and the simulation is fitted to the measured raw data using the Hook–Jeeves search algorithm. The intraparticle diffusivities of the three ions are hence measured and reported. 相似文献
146.
147.
Monitoring the structural health and integrity of coated components is of vital importance to increase their lifetime and the overall sustainability of the targeted applications. Here, the temporal oxidation behavior of TiN thin films is tracked using in situ sheet resistance measurements. Based on correlative film morphology, structure, and local composition data, it is evident that observed resistance changes are caused by oxidation of TiN. Thickness measurements of the remaining TiN under the oxide layer are in very good agreement with thicknesses deduced from in situ sheet resistance measurements. Hence, the in situ measured sheet resistance is an autonomous self‐reporting property useful for tracking the temporal oxidation behavior of TiN coatings. 相似文献
148.
Minds and Machines - I examine the abstraction/representation theory of computation put forward by Horsman et al., connecting it to the broader notion of modeling, and in particular, model-based... 相似文献
149.
In this work, we propose a controlled simplification strategy for degenerated points in symmetric 2D tensor fields that is based on the topological notion of robustness. Robustness measures the structural stability of the degenerate points with respect to variation in the underlying field. We consider an entire pipeline for generating a hierarchical set of degenerate points based on their robustness values. Such a pipeline includes the following steps: the stable extraction and classification of degenerate points using an edge labeling algorithm, the computation and assignment of robustness values to the degenerate points, and the construction of a simplification hierarchy. We also discuss the challenges that arise from the discretization and interpolation of real world data. 相似文献
150.
Minh‐Duc Hua Jochen Trumpf Tarek Hamel Robert Mahony Pascal Morin 《Asian journal of control》2019,21(4):1443-1458
This paper presents a new algorithm for online estimation of a sequence of homographies applicable to image sequences obtained from robotic vehicles equipped with vision sensors. The approach taken exploits the underlying Special Linear group structure of the set of homographies along with gyroscope measurements and direct point‐feature correspondences between images to develop temporal filter for the homography estimate. Theoretical analysis and experimental results are provided to demonstrate the robustness of the proposed algorithm. The experimental results show excellent performance and robustness even in the case of very fast camera motions (relative to frame rate) and severe occlusions. 相似文献