首页 | 官方网站   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   150篇
  免费   2篇
工业技术   152篇
  2023年   2篇
  2022年   4篇
  2021年   6篇
  2020年   2篇
  2019年   1篇
  2018年   11篇
  2017年   4篇
  2016年   3篇
  2015年   1篇
  2014年   10篇
  2013年   6篇
  2012年   10篇
  2011年   10篇
  2010年   8篇
  2009年   8篇
  2008年   7篇
  2007年   8篇
  2006年   6篇
  2004年   3篇
  2003年   2篇
  2000年   1篇
  1999年   1篇
  1998年   1篇
  1997年   2篇
  1994年   1篇
  1993年   1篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1982年   1篇
  1981年   1篇
  1980年   3篇
  1979年   2篇
  1977年   1篇
  1976年   2篇
  1973年   1篇
  1972年   2篇
  1971年   2篇
  1970年   3篇
  1969年   1篇
  1968年   1篇
  1967年   2篇
  1966年   3篇
  1965年   1篇
  1962年   1篇
  1961年   1篇
排序方式: 共有152条查询结果,搜索用时 125 毫秒
61.
The distribution of dislocation density has been investigated experimentally in aluminum single crystals with various concentrations of copper impurity (~0.0002, 0.005, and 0.05 wt %) that were obtained upon the crystallization of the melt under the action of a pressure and the gravitational-field component directed along the surface of the crystallization front. It has been found that a strong nonuniformity in the dislocation distribution arises in cross sections of the crystals in the direction of the field and this nonuniformity increases with increasing gravitational-field component and decreasing in the impurity concentration and rate of crystallization of the melt. It has been found that the degree of nonuniformity of the dislocation distribution in the crystals substantially depends on the magnitude of pressure at which the crystallization of the melt is realized and reaches a maximum at a certain pressure that is “optimum” for given conditions of the process of phase transformation.  相似文献   
62.
The aim of this study was to investigate the effects of meat fiber directions and air conditions on moisture and temperature developments, shrinkage, and effective diffusivity constants compared to homogenous minced meat samples. The lean meat with three fiber directions and minced meat samples were dried at temperatures of 48 and 70°C and air flow rates of 0.5, 1.0, and 1.7 m/s. The minced meat samples showed 1.0 ± 0.19 to 4.4 ± 0.03°C higher temperature values and 2.3 ± 0.004 to 6.2 ± 0.003% lower moisture losses than the lean meat samples in all fiber directions. The lowest temperatures were observed in lean meat with h 1 (normal flow, normal drying) fiber direction. The highest moisture loss and diffusion coefficient were observed in lean meat with h 2 (parallel flow, normal drying) and v (normal flow, parallel drying) fiber directions, which also possessed the shortest drying times (10.4 and 13.4 h, respectively). The estimated diffusion coefficient values ranged between 1.11 × 10?9 and 5.54 × 10?9. The results indicated that lean and minced meat samples differed in their drying behaviors in a tray dryer under the tested conditions with >90% reproducibility (or ≤10% coefficient of variation).  相似文献   
63.
64.
Management of engineered-to-order (ETO) components and their related information is a challenging task due to the complexity of information and its flow. Different information items are generated, accessed and exchanged between different organizations and they must continually flow through design, production, construction, and operations and maintenance. Current manual and labor-intensive methods are inefficient; as a result, information is frequently incomplete, inaccurate or unavailable during the life-cycle of a facility. This paper provides a vision of intelligent components, which know their identities, locations and history, and communicate this information to their environments. It proposes streamlining information flow through supply chains by utilizing radio frequency identification (RFID) technology. To explore the technical feasibility of intelligent components, component-related information flow patterns in ETO supply chains were identified and analyzed. Requirements analysis and corresponding technology deployment and testing were performed for three types of ETO components through different life-cycle phases. These experiments demonstrated that it is technically feasible to have intelligent components in construction supply chains by using RFID technology; that status information can be collected automatically; and that maintenance information can be stored and retrieved during the service life of a facility.  相似文献   
65.
This study reports the experimental results for the pyrolysis of pistachio shell under different conditions in a tubular reactor under a nitrogen flow. For the different conditions of pyrolysis temperature, nitrogen flow rate and heating rate, pyrolysis temperature of 773 K gave the highest bio-oil yield with a value of 27.7% when the heating rate and carrier gas flow rate were chosen as 300 K min−1 and 100 cm3 min−1, respectively. Column chromatography was applied to this bio-oil and its subfractions were characterized by elemental analysis, FT-IR and 1H-NMR. Aliphatic subfraction was conducted to gas chromatography–mass spectroscopy for further characterization. The results for the characterization show that using pistachio shell as a renewable source to produce valuable liquid products is applicable via pyrolysis. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
66.
Syndactyly type I is an autosomal dominant condition with complete or partial webbing between the third and fourth fingers or the second and third toes or both. We report here a previously undescribed phenotype of severe mesoaxial syndactyly and synostosis in patients born to affected parents. The characteristic features of these severe cases are (1) complete syndactyly and synostosis of the third and fourth fingers; (2) severe bone reduction in the proximal phalanges of the same fingers; (3) hypoplasia of the thumbs and halluces; (4) aplasia/hypoplasia of the middle phalanges of the second and fifth fingers; and (5) complete or partial soft tissue syndactyly of the toes. We report on three offspring with this phenotype from two different branches of a syndactyly type I family, suggesting that they may be homozygous for this condition. SSCP and linkage analysis indicated that neither HOXD13 nor other relevant genes in the chromosome 2q31 region was responsible for this phenotype.  相似文献   
67.
Neural Processing Letters - Reproducible machine learning models with less number of parameters and fast optimization are preferred in embedded system design for the applications of artificial...  相似文献   
68.
Magnetic Resonance Materials in Physics, Biology and Medicine - To investigate metabolic changes of mild cognitive impairment in Parkinson’s disease (PD-MCI) using proton magnetic resonance...  相似文献   
69.
Semiconductors - The transition from a two-domain to one-domain surface on a Si(100) substrate is investigated. It is demonstrated using reflection high-energy electron diffraction that at a...  相似文献   
70.
Microemulsions of styrene dispersed in water using sodium dodecyl sulphate and pentanol and polystyrene, isolated after the polymerizations were carried out to completion, were studied by photon correlation spectroscopy and time-averaged intensity measurements. Microemulsions contained droplets 40.8 nm in diameter. It was found that the size distributions of polystyrene were bimodal. The results indicate that smaller droplets in a microemulsion provide an increased surface area which can complete with micelles in the capture of radicals. The bimodal nature of the products is evidence for two mechanisms of initiation and particle growth.  相似文献   
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-23

京公网安备 11010802026262号