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   124篇
  免费   1篇
  国内免费   1篇
电工技术   2篇
化学工业   10篇
金属工艺   1篇
建筑科学   1篇
能源动力   11篇
轻工业   3篇
无线电   12篇
一般工业技术   35篇
冶金工业   15篇
原子能技术   2篇
自动化技术   34篇
  2024年   1篇
  2022年   2篇
  2021年   4篇
  2020年   1篇
  2019年   1篇
  2018年   4篇
  2017年   1篇
  2016年   6篇
  2015年   1篇
  2014年   2篇
  2013年   15篇
  2012年   5篇
  2011年   9篇
  2010年   4篇
  2009年   5篇
  2008年   6篇
  2007年   1篇
  2006年   9篇
  2005年   4篇
  2004年   1篇
  2003年   5篇
  2002年   3篇
  2001年   3篇
  2000年   3篇
  1999年   2篇
  1998年   5篇
  1997年   4篇
  1996年   3篇
  1995年   1篇
  1994年   2篇
  1993年   2篇
  1992年   6篇
  1991年   1篇
  1989年   1篇
  1984年   1篇
  1983年   1篇
  1981年   1篇
排序方式: 共有126条查询结果,搜索用时 62 毫秒
121.
Tetra- and hexasaccharides were arrayed on the exterior surface of cowpea mosaic virus by using a copper-catalyzed azide-alkyne cycloaddition reaction. Inoculation of chickens with these virus conjugates gave rise to large quantities of polyclonal anti-glycan IgY antibodies that displayed excellent avidity and specificity on analysis with printed glycan microarrays. Avian IgY antibodies are produced in significantly higher yield than is possible for mouse or rabbit IgG, and exhibit reduced cross reactivity with native mammalian proteins. For a tri-LacNAc antigen, affinity purification against immobilized mono-LacNAc was necessary to provide a set of antibodies with specific binding properties. Comparable performance was observed for the virus-based polyclonal versus a commercial monoclonal antibody raised against the globo-H tetrasaccharide; this highlights the utility of the glycan microarray for both quality control and rapid in-depth analysis. Virus-carbohydrate conjugates are promising candidates for development in diagnostic and immunotherapeutic applications.  相似文献   
122.
Ash gourd (Benincasa hispida Cogn) is a vegetable used in Asian countries and the peel contains high edible waxy materials. This paper reports extraction, characterization, and utilization of ash gourd peel wax as an edible coating in fruits; with strawberry (Fragaria ananassa) as a model system. Crude wax had melting point of 80°C and molecular weight by number (Mn) and molecular weight by weight (Mw) at 2,277 and 2,323 respectively. Dip method was used to coat crude wax as an emulsion on strawberry. Quantity of wax, concentration of sodium benzoate, and dip time were optimized and the values were 0.5%, 1M, and 3 min, respectively. Results were comparable with carnauba wax coating. Fruits without wax coating spoiled completely in less than 2 days at 25°C. Wax coating enhanced the shelf life to 7 days at 25°C and the properties such as texture, color, weight loss, titrable acidity, and microbial counts were well acceptable.  相似文献   
123.
A set of closure relations, in the context of a one-dimensional three-fluid model, is presented for the prediction of dryout and post-dryout heat transfer at high pressure (P/Pcr>0.3) conditions. It is shown that the traditional models based on low pressure data for interfacial friction, droplet size and the transition criteria for onset of annular flow cannot be readily extended to high pressure situations. The proposed new relations are validated by comparing with literature data in the pressure range of 30-200 bar, mass flux range of 500-3000 kg m−2 s−1 and tube inner diameters in the range of 10-25 mm. Good agreement is obtained for the dry out quality and the tube wall temperature in the post-dry out region except for cases of low mass flux at high pressures. The predictions show that at high pressure, high mass flux conditions, annular flow may prevail for low gas phase volume fraction, the droplet and the liquid film volume fractions being an order of magnitude higher than those encountered in typical air-water experiments.  相似文献   
124.
Ba0.70Ca0.30TiO3-(BCT),Ba(Zr0.2Ti0.8)O3-(BZT) ceramics were fabricated by conventional mixed oxide route to develop inorganic dielectric materials suitable for use as an insulator with high dielectric constant and low energy loss for capacitor applications. The structural phase transition, ferroelectric, dielectric and energy storage properties of BCT, BZT ceramic capacitors were investigated. Room temperature X-ray diffraction (XRD) patterns revealed prominent peaks corresponding to tetragonal perovskite crystal structure for both BCT, BZT solid solutions. Slim ferroelectric hysteresis (P-E) loops were observed for BCT, BZT solid solutions. Temperature dependent dielectric property measurements of BCT, BZT solid solutions have shown a high dielectric constant and low dielectric loss. Room temperature (300K) breakdown field strength and energy densities were obtained from the integral area of P-E loops. For the BCT ceramics, the largest recoverable energy (unreleased energy) density is 1.41 J/cm3 with dielectric breakdown strength as high as 150 kV/cm. For the BZT ceramics, the largest recoverable energy (unreleased energy) density is 0.71 J/cm3 with dielectric breakdown strength as high as 150 kV/cm. Bulk BCT, BZT ceramics have shown interesting energy densities; these might be the strong candidate materials for capacitor applications.  相似文献   
125.
Detection of Listeria monocytogenes in pigs and pork   总被引:1,自引:0,他引:1  
In this study, we surveyed hogs (n = 300) as well as pork products (ground pork and raw chitterlings) for Listeria monocytogenes. Pig specimens collected before (tonsil swabs) and after slaughter (tonsils, lymph nodes, carcass swabs, and rectal contents) were examined for L. monocytogenes by enrichment with conventional enrichment broths followed by subculturing to selective agar. A multiplex polymerase chain reaction assay targeting the highly conserved 16S rRNA gene of the Listeria species as well as the hlyA gene unique to L. monocytogenes was used to screen aliquots of the enrichment (method I) as well as to confirm presumptive Listeria colonies from Columbia agar with 0.05% glucose supplemented with polymyxin B-acriflavine-lithium chloride-ceftazidime-aesculin-mannitol (PALCAM; method II). Subculturing to PALCAM agar was the more sensitive of the two methods on the basis of the overall detection of Listeria. For hog tissues, method I detected L. monocytogenes (0.87% positive) and no other Listeria spp. in all samples (n = 1,849). In contrast, method II detected significantly more (P < 0.05) L. monocytogenes (2.38%) and Listeria spp. (0.38%) in these tissues. For small intestines (n = 300 raw chitterlings), L. monocytogenes was identified in 8.3% of enrichments with University of Vermont modified Listeria enrichment broth; plating to PALCAM slightly improved recovery (9%). Overall, ground pork samples (n = 340) harbored L. monocytogenes (45% positive) and other Listeria species (1.5% positive), as determined by method I. Subculturing to PALCAM significantly (P < 0.05) improved the detection of L. monocytogenes (50.2%) but not that of other Listeria species (1.7%). L. monocytogenes isolates (n = 243) were assigned to serotype 1 (53.5%), serotype 4 (25%), and serotypes other than 1 and 4 (21.4%).  相似文献   
126.
Chalcopyrite copper indium aluminum diselenide (CuIn0.81Al0.19Se2) compound is prepared by direct reaction of high purity elemental copper, indium, aluminum and selenium in their stoichiometric proportion. Structural and compositional characterizations of pulverized material confirm the formation of a single phase, polycrystalline nature. CuInAlSe2 (CIAS) thin films are deposited on organically cleaned soda lime glass substrates using flash evaporation technique by varying the substrate temperatures in the range from 423 K to 573 K. Influence of substrate temperature observed by X-ray diffraction (XRD), scanning electron microscope (SEM), optical and electrical measurement. CIAS Films grown at different substrate temperatures are polycrystalline in nature, exhibiting a chalcopyrite structure with lattice parameters a = ∼0.576 nm and c = ∼1.151 nm. The crystallinity in the films increases with increasing substrate temperature up to 473 K, and tend to degrade at higher substrate temperatures. Optical band gap is in the range of 1.20 eV–1.38 eV and the absorption coefficient is close to 105 cm−1. Electrical characterization reveals p-type conductivity and the structural, morphological and optical properties indicate potential use of CIAS thin films as an absorber layer for thin film solar cell applications.  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