首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   113篇
  免费   4篇
电工技术   2篇
化学工业   23篇
金属工艺   1篇
机械仪表   10篇
建筑科学   5篇
矿业工程   1篇
能源动力   1篇
轻工业   5篇
水利工程   2篇
石油天然气   1篇
无线电   15篇
一般工业技术   11篇
冶金工业   24篇
自动化技术   16篇
  2020年   3篇
  2019年   2篇
  2018年   1篇
  2017年   1篇
  2016年   3篇
  2015年   5篇
  2014年   5篇
  2013年   11篇
  2012年   2篇
  2011年   8篇
  2010年   8篇
  2009年   9篇
  2008年   10篇
  2007年   5篇
  2006年   4篇
  2005年   1篇
  2004年   2篇
  2003年   1篇
  2002年   1篇
  1999年   2篇
  1998年   9篇
  1997年   3篇
  1996年   3篇
  1994年   1篇
  1993年   3篇
  1990年   1篇
  1988年   1篇
  1986年   1篇
  1985年   2篇
  1983年   2篇
  1982年   1篇
  1980年   1篇
  1976年   3篇
  1974年   1篇
  1972年   1篇
排序方式: 共有117条查询结果,搜索用时 15 毫秒
1.
Storage lipids, triacylglycerols (TAG), and steryl esters (SE), are predominant constituents of lipid droplets (LD) in fungi. In several yeast species, metabolism of TAG and SE is linked to various cellular processes, including cell division, sporulation, apoptosis, response to stress, and lipotoxicity. In addition, TAG are an important source for the generation of value-added lipids for industrial and biomedical applications. The fission yeast Schizosaccharomyces pombe is a widely used unicellular eukaryotic model organism. It is a powerful tractable system used to study various aspects of eukaryotic cellular and molecular biology. However, the knowledge of S. pombe neutral lipids metabolism is quite limited. In this review, we summarize and discuss the current knowledge of the homeostasis of storage lipids and of the role of LD in the fission yeast S. pombe with the aim to stimulate research of lipid metabolism and its connection with other essential cellular processes. We also discuss the advantages and disadvantages of fission yeast in lipid biotechnology and recent achievements in the use of S. pombe in the biotechnological production of valuable lipid compounds.  相似文献   
2.
This paper summarizes the major results of the joint Indo-Soviet experiment for testing the Indianmhd generator channel section, designed and fabricated at the Bhabha Atomic Research Centre, Bombay, which was carried out at the U-02 facility in Moscow, USSR, in May 1980. The total test duration was 65 hours and included electrophysical tests and life tests under applied electric fields. The main purpose of the tests was to substantiate the physical concepts, computer codes, design features and special processing techniques involved in the development ofmhd generators for the Indian pilot plant at Tiruchirapalli. The experimental observations on the phenomena of heat transfer to the walls, gas dynamics in the channel, electrical characteristics of the generator and near-electrode processes including the analysis of arc spots correlate with the theoretical estimates based on present understanding of the physical processes occuring in similarmhd generators. The post-operational inspection of the channel section and extensive investigation of materials through microscopic analysis, chemical analysis and x-ray analysis are also reported in this paper. The joint test programme has clearly demonstrated the definite operating capability of the test section and has given sufficient information and encouragement for building better and improved channels for the future.  相似文献   
3.
The electrical resistance of copper foil under shock compression is measured. The electrical resistance and electrical conductivity are plotted as functions of the shock pressure in the interval up to 20 GPa. These dependences are monotonic and have no visible inflections or singularities. A qualitative dependence of the electrical resistance of the metal on the shock impedance of the material of the block containing the sample is found. A comparison of the data obtained in this study with results of other authors shows that it is important to take into account the block material, the shape and thickness of the sample, and the procedure of determining the state of the sample.  相似文献   
4.
In this paper a fully three dimensional, multiphase, micro-scale solid oxide fuel cell anode transport phenomena numerical model is proposed and verified. The Butler-Volmer model was combined with empirical relations for conductivity and diffusivity - notably the Fuller-Shetler-Giddings equation, and the Fickian model for transport of gas reagents. FIB-SEM tomography of a commercial SOFC stack anode was performed and the resulting images were processed to acquire input data. A novel method for estimating local values of Triple Phase Boundary length density for use in a three-phase, three-dimensional numerical mesh was proposed. The model equations are solved using an in-house code and the results were verified by comparison to an analytical solution within the range of its applicability. A limited parametric study was performed to qualitatively assess simulation performance and impact of heterogeneity. Despite the high dependence of the SOFC anode performance on the geometry of its anisotropic, three-phase microstructure there are very few micro-scale numerical models simulating transport phenomena within these electrodes.  相似文献   
5.
6.
The hydrolytic dehalogenation of rac‐1,3‐dibromobutane catalyzed by the haloalkane dehalogenase LinB from Sphingobium japonicum UT26 proceeds in a sequential fashion: initial formation of intermediate haloalcohols followed by a second hydrolytic step to produce the final diol. Detailed investigation of the course of the reaction revealed favored nucleophilic displacement of the sec‐halogen in the first hydrolytic event with pronounced R enantioselectivity. The second hydrolysis step proceeded with a regioselectivity switch at the primary position, with preference for the S enantiomer. Because of complex competition between all eight possible reactions, intermediate haloalcohols formed with moderate to good ee ((S)‐4‐bromobutan‐2‐ol: up to 87 %). Similarly, (S)‐butane‐1,3‐diol was formed at a maximum ee of 35 % before full hydrolysis furnished the racemic diol product.  相似文献   
7.
Technological features of the manufacture of sets of thickness gauges for use in measuring the thickness of nickel coatings on the D16T aluminum alloy up to 100 μm with error 0.12–0.63 μm (0.4–0.6%) sufficient for inspection of thickness gauges with standard error at least 1% are presented. Translated from Izmeritel’naya Tekhnika, No. 3, pp. 22–23, March, 2009.  相似文献   
8.
An analysis is made of two types of negative differential conductivity in semiconductors and semiconducting superstructures containing ND shallow impurity atomic systems (centers), in crossed electric and magnetic fields corresponding to nonequilibrium phase transitions of n e , where n e is the average density of nonequilibrium carriers (electrons). It is observed that these semiconductors and semiconducting superstructures in crossed electric and magnetic fields may be used to fabricate various semiconductor devices and apparatus, and also memory elements for the acquisition, storage, and protection of information under extreme conditions. Pis’ma Zh. Tekh. Fiz. 25, 39–44 (August 26, 1999)  相似文献   
9.
Small hydrophobic ligands identifying intracellular protein deposits are of great interest, as protein inclusion bodies are the pathological hallmark of several degenerative diseases. Here we report that fluorescent amyloid ligands, termed luminescent conjugated oligothiophenes (LCOs), rapidly and with high sensitivity detect protein inclusion bodies in skeletal muscle tissue from patients with sporadic inclusion body myositis (s‐IBM). LCOs having a conjugated backbone of at least five thiophene units emitted strong fluorescence upon binding, and showed co‐localization with proteins reported to accumulate in s‐IBM protein inclusion bodies. Compared with conventional amyloid ligands, LCOs identified a larger fraction of immunopositive inclusion bodies. When the conjugated thiophene backbone was extended with terminal carboxyl groups, the LCO revealed striking spectral differences between distinct protein inclusion bodies. We conclude that 1) LCOs are sensitive, rapid and powerful tools for identifying protein inclusion bodies and 2) LCOs identify a wider range of protein inclusion bodies than conventional amyloid ligands.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号