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   216篇
  免费   14篇
电工技术   6篇
综合类   1篇
化学工业   45篇
金属工艺   8篇
机械仪表   6篇
能源动力   5篇
轻工业   32篇
水利工程   3篇
无线电   17篇
一般工业技术   48篇
冶金工业   17篇
自动化技术   42篇
  2024年   1篇
  2023年   5篇
  2022年   7篇
  2021年   12篇
  2020年   14篇
  2019年   11篇
  2018年   22篇
  2017年   15篇
  2016年   12篇
  2015年   13篇
  2014年   13篇
  2013年   18篇
  2012年   15篇
  2011年   13篇
  2010年   9篇
  2009年   10篇
  2008年   9篇
  2007年   9篇
  2006年   6篇
  2005年   1篇
  2004年   3篇
  2003年   2篇
  2002年   2篇
  2001年   1篇
  1999年   1篇
  1998年   1篇
  1996年   1篇
  1994年   1篇
  1990年   1篇
  1974年   1篇
  1970年   1篇
排序方式: 共有230条查询结果,搜索用时 15 毫秒
51.
A review containing 83 references on the chemistry aspects (mechanism and structure–property relationships) for IPN synthesis is presented.  相似文献   
52.
53.
Metallurgical and Materials Transactions B - A phenomenological model for the reduction of iron ore/carbon composite pellets in a multi-layer bed rotary hearth furnace has been developed. A single...  相似文献   
54.
The efficient use of energy is essential to address concerns of cost and sustainability. Many data centers contain MapReduce clusters to process Big Data applications. A large number of machines and fault tolerance capabilities make MapReduce clusters energy inefficient. In this paper, we present a Configurator based on performance and energy models to improve the energy efficiency of MapReduce systems. Our solution is novel as it takes into account the dependence of the performance and energy consumption of a cluster on MapReduce parameters. While this dependence is known, we are the first to model it and design a Configurator to optimize these parameter settings for maximizing the energy efficiency of MapReduce systems. Our empirical evaluations show that the Configurator can result in up to 50% improvement in the energy efficiency of typical MapReduce applications in two architecturally different clusters.  相似文献   
55.
Joint watermarking and encryption is an upcoming security solution that combines leading but complementary techniques to achieve an enhanced security level. Real time applications using joint watermarking and encryption framework has three requirements: data to be efficiently compressed, watermarking technique to sustain compression, and encryption technique to be developed in a way so as not to disturb the compression efficiency. Finding an optimal solution that combines the three techniques while fulfilling these requirements is a challenging problem. This paper thus, proposes a wavelet domain based joint watermarking and encryption framework that employs singular value decomposition based watermark embedding and sign bit encryption prior to compression. The varying significance of different subbands has been considered to encrypt the data without adversely effecting the compression ratio. Experimental analysis using various evaluation parameters and attack scenarios has revealed the ability of the proposed framework to prove content-ownership, even from the encrypted data. Comparative analysis with the existing techniques reflect its ability to provide better security with less computational resources. This makes it a preferable solution for data security at all stages of data archival, transmission or distribution.  相似文献   
56.
57.
在7178铝合金中添加不同比例的Al-10%TiB中间合金,考察TiB对铝合金的晶粒细化、磨损和压缩变形行为的影响。组织观察表明,TiB颗粒起着晶粒细化剂的作用,导致生成球状枝晶。当Al-TiB中间合金的添加量超过20%时,合金的耐磨性和强度随着中间合金添加量的增加而降低,即使其枝晶组织变得更细而接近于球状组织。  相似文献   
58.
Present investigation deals with the hot corrosion behaviour of the NiCrAlY coatings deposited by HVOF technique on Superni76 under cyclic conditions at 900  °C in the presence of Na2SO4 + 60% V2O5 salt. The weight change behaviour of the coatings was followed with time up to 200 cycles and K p value was calculated for the hot corrosion process. Surface and cross-section of the corroded samples were examined by FESEM/EDS and XRD to follow the progress of corrosion up to 200 cycles. In earlier cycles, the corrosive species oxidised top surface of the coatings. With increasing number of cycles, oxidation of the coatings occurred up to 40-μm depth. A Cr-depleted band was seen below the oxide scale. Further increase in number of cycles led to migration and oxidation of Al to form Al2O3 sublayer at coating/scale interface, thereby leading to formation of Al-depleted zone in the coating below the Al2O3 sublayer. The corrosion resistance of the NiCrAlY coatings is attributed to the formation of the continuous and dense Al2O3 sublayer at the coating/scale interface, which acts as barrier to the migration of Cr to the surface. The appearance of Al3Y after 100 and 200 cycles also contributes to the increased corrosion resistance of coatings after 100 and 200 cycles.  相似文献   
59.
Many fruit and vegetable processing operations are examining technologies to reduce effluent volume and encourage water recovery and reuse. Implementing technologies and programs to promote in-plant reuse and recycling of discharge water is cost-effective and may improve processing efficiency. The efficacy of ozonation of defrost water has been investigated to determine the appropriate treatment level for in-plant reuse at a fruit processing plant in Clovis, California. Treatments of 0.5 ppm and 1.0 ppm of aqueous ozone achieved water quality acceptable for in-plant reuse, while an ozone treatment of 1.0 ppm was needed to significantly (P < 0.05) reduced the microbial load of flume wash effluent.  相似文献   
60.
During studies on exploiting the catalytic promiscuity of crude porcine pancreas lipase (PPL) in ionic liquid for CC bond formations, bovine serum albumin (BSA) was found to be competing for these reactions. After a detailed investigation, we establish that these transformations are possible by unspecific protein catalysis rather than catalytic promiscuity of “PPL” – a first insight into the role of protein impurities in crude enzyme. Thus, a novel and highly efficient, environmentally friendly approach involving synergistic catalysis by bovine serum albumin‐1‐butyl‐3‐methylimidazolium bromide (BSA‐[bmim]Br) has been developed for the synthesis of (E)‐α,β‐unsaturated compounds including a one‐pot cascade synthesis of cinnamic acids and coumarins via aldol, Knoevenagel and Knoevenagel–Doebner condensations.  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