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   318篇
  免费   12篇
  国内免费   1篇
电工技术   3篇
化学工业   112篇
金属工艺   3篇
机械仪表   3篇
建筑科学   3篇
能源动力   8篇
轻工业   25篇
水利工程   2篇
石油天然气   1篇
无线电   32篇
一般工业技术   79篇
冶金工业   22篇
原子能技术   1篇
自动化技术   37篇
  2024年   2篇
  2023年   2篇
  2022年   11篇
  2021年   10篇
  2020年   11篇
  2019年   14篇
  2018年   8篇
  2017年   10篇
  2016年   9篇
  2015年   13篇
  2014年   11篇
  2013年   16篇
  2012年   9篇
  2011年   6篇
  2010年   7篇
  2009年   5篇
  2008年   13篇
  2007年   9篇
  2006年   14篇
  2005年   7篇
  2004年   12篇
  2003年   6篇
  2002年   4篇
  2001年   7篇
  2000年   8篇
  1999年   4篇
  1998年   3篇
  1997年   11篇
  1996年   6篇
  1995年   6篇
  1994年   6篇
  1993年   4篇
  1992年   3篇
  1991年   6篇
  1990年   4篇
  1988年   3篇
  1987年   5篇
  1985年   2篇
  1984年   5篇
  1983年   4篇
  1982年   4篇
  1981年   6篇
  1979年   3篇
  1978年   3篇
  1976年   4篇
  1975年   3篇
  1974年   3篇
  1972年   1篇
  1969年   3篇
  1968年   1篇
排序方式: 共有331条查询结果,搜索用时 31 毫秒
321.
A strong acid ferromagnetic cation-exchange resin based on styrene divinylbenzene polymer has been prepared and characterized.  相似文献   
322.
We report the preparation of a range of rf-sputtered FeN compounds by control of the sputtering parameters. Contrary to earlier reports, we have shown that single phase Fe4N can be synthesized by the exclusive use of N2 gas. However, adding H2 to the sputtering gas improves the ease of formation and the range of control. The X-ray diffraction and Mössbauer data are presented.  相似文献   
323.
Tracking Uncertainty with Probabilistic Logic Circuit Testing   总被引:1,自引:0,他引:1  
The diverse nature of the faults and defects that may occur at nanoscale ranges necessitates new techniques for ATPG. This article proposes an efficient technique that relies on a probabilistic approach to detect and diagnose nontraditional faults and defects.  相似文献   
324.
325.
326.
The Fusarium verticillioides produces a mycotoxin, that is, fumonisin b1 (Fb1), which commonly infects corn and agricultural commodities. The Fb1 showed hepatotoxicity, neurotoxicity, and carcinogenicity in animals. Hence, the present investigation aimed to evaluate the effect of apocynin (AP) on Fb1-induced neurotoxic effects and its mechanism in the mice model and cell line. The male Balb/c mice, with the 6.75 mg/kg bwt of Fb1 were injected subcutaneously for 5 days to induce neurotoxicity. A significant elevation of serotonin (5-HT) was observed in mice treated with Fb1 in the whole brain showing biogenic amines may reflect Fb1 neurotoxicity, but the negatively regulated mechanisms were attenuated by the pretreatment of AP. In addition, AP pretreatment normalized apoptotic changes in histology and immunohistochemistry studies. In Western blotting studies, apoptotic genes were upregulated and oxidative stress genes were downregulated due to Fb1 treatment; while treating with AP, these gene expressions were rectified. Further cell cytotoxicity was investigated by MTT and lactate dehydrogenase (LDH) assays in SH-SY5Y cell line. MTT and LDH assays indicated the IC50 value to be 150 µM of Fb1, which was protected by 100 µg of AP. The electron microscopy evaluated the Fb1-induced apoptotic conditions and its cell morphology recovery by AP. These results suggest that nicotinamide adenine dinucleotide phosphate hydrogen oxidase–mediated reactive oxygen species is the primary upstream signal leading to increased Fb1-mediated neurotoxicity in mice. The use of the antioxidant AP reversed the toxin-induced oxidative stress and apoptosis by its antioxidant potency.  相似文献   
327.
328.
The dietary fibers were mainly isolated from seed hull of field beans (Phaseolus vulgaris), waste pulp of pineapple (Ananas camosus) as well as from whole wheat flour and, the fiber yields were 16.8, 2.0 and 7.0g/100g, respectively. These isolated fibers were included in sponge cake preparation by partially replacing all-purpose flour (maida) by 5% (w/w). Cakes and cake batter were evaluated for pH change, specific gravity, volume, moisture content, and color. The sensory characteristics and volume of the cakes were not altered with the inclusion of isolated fiber in the cake. The sensory quality evaluation showed that the fiber incorporated cakes were acceptable similar to the cake without added fiber. Incorporation of various fibers in the cake preparation increased the total dietary fiber content of the product by 4-6%.  相似文献   
329.
A prevalent diabetic complication is Diabetic Retinopathy (DR), which can damage the retina’s veins, leading to a severe loss of vision. If treated in the early stage, it can help to prevent vision loss. But since its diagnosis takes time and there is a shortage of ophthalmologists, patients suffer vision loss even before diagnosis. Hence, early detection of DR is the necessity of the time. The primary purpose of the work is to apply the data fusion/feature fusion technique, which combines more than one relevant feature to predict diabetic retinopathy at an early stage with greater accuracy. Mechanized procedures for diabetic retinopathy analysis are fundamental in taking care of these issues. While profound learning for parallel characterization has accomplished high approval exactness’s, multi-stage order results are less noteworthy, especially during beginning phase sickness. Densely Connected Convolutional Networks are suggested to detect of Diabetic Retinopathy on retinal images. The presented model is trained on a Diabetic Retinopathy Dataset having 3,662 images given by APTOS. Experimental results suggest that the training accuracy of 93.51% 0.98 precision, 0.98 recall and 0.98 F1-score has been achieved through the best one out of the three models in the proposed work. The same model is tested on 550 images of the Kaggle 2015 dataset where the proposed model was able to detect No DR images with 96% accuracy, Mild DR images with 90% accuracy, Moderate DR images with 89% accuracy, Severe DR images with 87% accuracy and Proliferative DR images with 93% accuracy.  相似文献   
330.
This work concerns a novel means to generate wholly thermoplastic composites based on low-melting thermoplastics reinforced with high-melting thermotropic liquid crystalline polymers (TLCPs). A novel dual extrusion process was employed to generate nylon-11 fibers that are reinforced with continuous fibrils of a hydroquinone-based liquid crystalline polyester (DuPont TLCP, HX8000). These composite fibers display tensile properties significantly higher than those predicted by composite theory. These fibers were subsequently woven into a fabric, which in turn serves as a composite preform. Several layers of the fabric preform were stacked and consolidated to yield a composite plaque. The consolidation was carried out at temperatures just high enough for nylon-11 to melt, but well below the melting temperature of HX8000. Fabric preform composites based on the composite fibers with ∼35 wt% HX8000 gave modulus values close to five and one half times that of nylon-11, and strength values approximately two and one half times that of nylon-11. The tensile and flexural properties of these composites are superior to continuous glass-fiber reinforced composites at comparable loadings on a volume basis. Moreover, as the reinforcing fibrils are already encapsulated by the matrix, fiber wetting and fabric impregnation issues that are critical in the fabrication of continuous glass and carbon fiber composites are eliminated.  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