全文获取类型
收费全文 | 83篇 |
免费 | 9篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 18篇 |
金属工艺 | 3篇 |
机械仪表 | 3篇 |
建筑科学 | 1篇 |
矿业工程 | 1篇 |
能源动力 | 3篇 |
轻工业 | 12篇 |
无线电 | 11篇 |
一般工业技术 | 26篇 |
冶金工业 | 7篇 |
自动化技术 | 8篇 |
出版年
2023年 | 1篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2014年 | 4篇 |
2013年 | 8篇 |
2012年 | 5篇 |
2011年 | 6篇 |
2010年 | 3篇 |
2009年 | 5篇 |
2008年 | 7篇 |
2007年 | 3篇 |
2006年 | 4篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 4篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1987年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有94条查询结果,搜索用时 0 毫秒
51.
52.
C. Morales H. Juarez T. Diaz Y. Matsumoto E. Rosendo G. Garcia M. Rubin F. Mora M. Pacio A. García 《Microelectronics Journal》2008,39(3-4):586-588
SnO2 films were deposited by atmospheric pressure chemical vapor deposition (APCVD) on glass substrates using tin tetrachloride as the tin precursor, H2O vapor and O3–O2 as oxidizing agents and O3–O2 with HF as the fluorine dopant source. The deposition temperatures varied from 200 to 350 °C. It is shown that the deposition temperature and the oxidizing agent used are related with the structure, optical transmission percent, and resistivities of the films. Finally, films with good transmission percent between 85% and 90% in the visible spectrum and lower resistivities ranged from 0.1 to 0.02 Ω cm are obtained. 相似文献
53.
A rotating machinery test rig was instrumented with fiber Fabry-Perot interferometer strain sensors for condition monitoring of rolling element bearings. Strain variations produced by ball passes were observed and analyzed in the time and frequency domain. Wavelength division multiplexing was utilized to simultaneously monitor the sensors with analog and digital readout systems--analog for high bandwidth and digital for high dynamic range and the monitoring of multiple sensors. The effects of imbalance on the shaft, changes in rotational speed, effects on the rotor system, and detection of bearing defects were investigated. Frequency peaks observed in the bearing sensor spectra closely matched predicted values. Imbalance and rotational speed tests showed good agreement with expected trends, and bearing defects were successfully detected. 相似文献
54.
55.
56.
Germn P. Hernndez A.S. Juarez M.C. Resendiz X. Mathew 《Solar Energy Materials & Solar Cells》2006,90(15):2289-2296
Development of a proper electrical contact between CdTe and the metallic substrate is one of the hurdles in the fabrication of flexible solar cells on metal foils. From the point of view of matching thermal expansion coefficient; Molybdenum (Mo) is favored as the substrate material. However, the large difference in work, function of CdTe and Mo necessitates a no-rectifying interlayer. In this work we are presenting some preliminary results of our efforts on developing a pseudo-ohmic layer between CdTe and Mo substrate. A thin interlayer of Au seems to reduce the contact resistance. The dependence of the film morphology on the substrate material as well as the substrate temperature is discussed. 相似文献
57.
Kalina Lígia Cavalcante de Almeida Farias Aires Juarez Everton de Farias Aires Aluízio Freire da Silva Júnior Cleide Maria Diniz Pereira da Silva e Silva 《Drying Technology》2013,31(16):2034-2046
AbstractThis study presents two liquid diffusion models to represent the convective drying of apple, osmotically dehydrated in sucrose solution, cut into parallelepiped-shaped pieces. Model 1 considered water diffusivity and the volume of the slices with constant values. Model 2 considered water effective diffusivity and the dimensions of the slices as variable. The numerical solution of the three-dimensional diffusion equation in Cartesian coordinates was obtained through the finite volume method, with a fully implicit formulation and boundary condition of the third kind. Process parameters were estimated by an optimizer using experimental data. A spatial distribution analysis was carried out for water effective diffusivity and moisture content in the apple slices. The results showed that the concentration of the osmotic solution used in the pretreatment influenced the drying process and that the mathematical model that considered a variable diffusivity and shrinkage was more suitable to describe the experimental data. 相似文献
58.
The elevated expression of the urokinase-type plasminogen activator gene, which is necessary for the invasive phenotype of several types of cancers, is controlled by growth factors such as epidermal growth factor, transforming growth factor a, and fibroblast growth factor which bind to and activate protein tyrosine kinase transmembrane receptors. Since these activated receptors communicate with the nucleus via a signaling pathway in which c-Raf-1, mitogen-activated protein kinase kinase 1 (MEK1), and the extracellular signal-regulated kinases are sequentially activated, we determined the effect of a specific MEK1 inhibitor (PD 098059) on urokinase expression in two squamous cell carcinoma cell lines (UM-SCC-1 and MDA-TU-138) characterized as avid secretors of the plasminogen activator. PD 098059 treatment of either cell line reduced the amount of secreted urokinase in a dose-dependent manner. In contrast, a compound (daidzein) chemically unrelated to PD 098059 had little effect on urokinase secretion. The effect of PD 098059 on urokinase secretion in UM-SCC-1 cells was reversible and correlated with decreased extracellular signal-regulated kinase 1 activity. PD 098059 caused a dose-dependent reduction in the in vitro invasiveness of UM-SCC-1 cells whereas it had little effect on proliferation rates. Transient transfection assays with a chloramphenicol acetyl transferase reporter driven by the urokinase promoter indicated that diminished secretion of the protease was largely a consequence of reduced promoter activity. These findings suggest that interfering with MEK1 may provide a novel means of controlling the invasiveness of tumors in which this signaling cascade is activated by autocrine and/or paracrine growth factors. 相似文献
59.
MP De Leon T Yanagi M Kikuchi J Mu O Ayau V Matta M Paz S Juarez H Kanbara I Tada K Hirayama 《Canadian Metallurgical Quarterly》1998,28(12):1867-1874
Fifty fresh isolates of Trypanosoma cruzi from Triatoma dimidiata vectors and 31 from patients with Chagas' disease were analysed for DNA polymorphisms within the 432-bp core region of the cruzipain gene which encodes the active site of cathepsin L-like cystein proteinase. The cruzipain gene showed signs of polymorphism consisting of four different DNA sequences in Central and South American isolates of T. cruzi. The PCR fragments of Guatemalan isolates could be divided into three groups, Groups 1, 2 and 3, based on different patterns of single-stranded DNA conformation polymorphism. All of the strains isolated from Brazil, Chile, and Paraguay, except for the CL strain, showed a Group 4 pattern. Two to four isolates from each group were analysed by cloning and sequencing. A silent mutation occurred between Groups 1 and 2, and five nucleotides and two aa substitutions were detected between Groups 1 and 3. The DNA sequence of Group 4 contained five nucleotides and one aa substitution from Group 1. All of the DNA sequences corresponded well with the single-stranded DNA conformation polymorphism. The Group 1 isolates, the majority in the Guatemalan population (70/81, 86.4%), were isolated from both triatomines and humans, but Group 3 were isolated only from humans. Moreover, the Group 2 isolates were detected only in triatomine vectors (9/50; 18%), but never in humans (0/32, P<0.05) suggesting that this group has an independent life-cycle in sylvatic animals and is maintained by reservoir hosts other than humans. 相似文献
60.