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   186篇
  免费   15篇
  国内免费   5篇
电工技术   1篇
综合类   1篇
化学工业   31篇
金属工艺   4篇
机械仪表   9篇
建筑科学   2篇
矿业工程   1篇
能源动力   11篇
轻工业   85篇
石油天然气   3篇
无线电   15篇
一般工业技术   15篇
冶金工业   3篇
原子能技术   3篇
自动化技术   22篇
  2024年   4篇
  2023年   15篇
  2022年   17篇
  2021年   24篇
  2020年   9篇
  2019年   6篇
  2018年   14篇
  2017年   13篇
  2016年   10篇
  2015年   7篇
  2014年   9篇
  2013年   8篇
  2012年   8篇
  2011年   3篇
  2010年   2篇
  2009年   5篇
  2008年   1篇
  2007年   10篇
  2006年   5篇
  2005年   1篇
  2004年   2篇
  2003年   3篇
  2002年   5篇
  2001年   1篇
  2000年   2篇
  1999年   2篇
  1998年   3篇
  1995年   2篇
  1994年   1篇
  1990年   4篇
  1987年   3篇
  1986年   4篇
  1985年   2篇
  1979年   1篇
排序方式: 共有206条查询结果,搜索用时 15 毫秒
1.
2.
Chronic inflammation represents a long-term reaction of the body's immune system to noxious stimuli. Such a sustained inflammatory response sometimes results in lasting damage to healthy tissues and organs. In fact, chronic inflammation is implicated in the development and progression of various diseases, including cardiovascular diseases, respiratory diseases, metabolic diseases, neurodegenerative diseases, and even cancers. Targeting nonresolving inflammation thus provides new opportunities for treating relevant diseases. In this review, we will go over several chronic inflammation-associated diseases first with emphasis on the role of inflammation in their pathogenesis. Then, we will summarize a number of natural products that exhibit therapeutic effects against those diseases by acting on different markers in the inflammatory response. We envision that natural products will remain a rich resource for the discovery of new drugs treating diseases associated with chronic inflammation.  相似文献   
3.
Active queue management (AQM) is an effective method used in Internet routers for congestion avoidance, and to achieve a tradeoff between link utilization and delay. The de facto standard, the random early detection (RED) AQM scheme, and most of its variants use average queue length as a congestion indicator to trigger packet dropping. This paper proposes a novel packet dropping scheme, called self-tuning proportional and integral RED (SPI-RED), as an extension of RED. SPI-RED is based on a self-tuning proportional and Integral feedback controller, which considers not only the average queue length at the current time point, but also the past queue lengths during a round-trip time to smooth the impact caused by short-lived traffic dynamics. Furthermore, we give theoretical analysis of the system stability and give guidelines for selection of feedback gains for the TCP/RED system to stabilize the average queue length at a desirable level. The proposed method can also be applied to the other variants of RED. Extensive simulations have been conducted with ns2. The simulation results have demonstrated that the proposed SPI-RED algorithm outperforms the existing AQM schemes in terms of drop probability and stability.  相似文献   
4.
网络存储技术是当前存储应用的发展趋势,IP SAN是其中的热点之一,如何构建网络存储系统直接关系到校园网络的安全性。介绍了SAN、ISCSI协议及其工作原理,结合高校数据中心存储的需求分析,提出了一种基于ISCSI协议的经济实用、高性价比的高校数据中心网络存储设计方案。  相似文献   
5.
6.
7.
利用冷冻反向成球技术,即将乳酸钙和黄原胶复配成芯液后,冷冻为小球,然后置于常温放置的海藻酸钠-低酯果胶复合溶液中,蒸馏水漂洗后用壳聚糖溶液固化,制得爆珠。以跌落测试、质构分析作为主要评判标准,并观察小球的成球性,得到爆珠的最佳制作工艺。为丰富爆珠的营养价值和口感,将具有药食两用价值的连翘叶提取物加入爆珠芯液中,以感官评分为标准,通过单因素试验和正交试验得到连翘叶风味爆珠的最佳制备工艺。试验结果表明,爆珠的最佳制备工艺为:成球反应时间10 min、海藻酸钠-低酯果胶复合溶液浓度0.6%(w/w)、芯液添加量400 μL;连翘叶风味爆珠芯液的最佳工艺配方为:连翘叶提取物载入量3%(w/w)、白砂糖载入量8%(w/w)、黄原胶载入量0.2%(w/w)。该结果可为连翘叶的开发利用提供科学依据,为风味爆珠的研发提供工艺参考。  相似文献   
8.
Hierarchical-Beta zeolites have been hydrothermally synthesized by adding a new gemini organic surfactant. The used gemini surfactant play the role of a “pore-forming agents” on the mesoscale, on the same time, providing alkaline environment for the system. With this hierarchical Beta zeolite as the core support, we successfully prepared a shell layer of Ni-containing (22 wt%) petal-like core-shell-like catalyst and applied it to bioethanol steam reforming. At the reaction temperature of 350 °C–550 °C, the conversion rate of ethanol and the selectivity of hydrogen were always above 85% and 70%. After reaction of 100 h on stream at 400 °C, there were not obvious inactivation could be observed on NiNPs/OH-MBeta catalyst.  相似文献   
9.
Along with the progress in nanoscience, a variety of advanced functional nanomaterials were constructed to develop effective and innovative analytical techniques for food safety surveillance. In this review, we summarized the advanced analytical methods that have been developed based upon advanced functional nanomaterials, including plasmonic nanomaterial-based colorimetric methods, fluorescent nanomaterial-based fluorescent methods, advanced functional material-based molecular imprinting technology, advanced functional material-based chromatographic methods, plasmonic nanomaterial-based surface enhanced Raman scattering technology, and advanced functional material-based electrochemical methods. This review provides a progressive roadmap for further development of portable, rapid, and in situ detection technology to promote food safety surveillance from bench to market and eventually reduce the gap between research in the laboratory and industrial applications.  相似文献   
10.
本文以抑菌圈直径为指标,采用单因素试验和响应面法对解淀粉芽孢杆菌HRH317菌株产抗菌肽的发酵条件进行优化,并对该抗菌肽的抑菌谱及其最小抑菌浓度(MIC)进行了研究。得到最佳发酵条件为:pH7.5,装液量为50 mL,接种量3%,培养时间13h、温度38.5℃、转速145r/min,抗菌肽含量441.56±1.24 μg/mL。在此条件下抗菌肽的抑菌圈直径达15.95 mm。针对9种指示菌的抑菌谱结果表明,抗菌肽对枯草芽孢杆菌、金黄色葡萄球菌抑制效果最好,其次是霉菌、酵母菌。其中,抗菌肽对枯草芽孢杆菌、金黄色葡萄球菌的MIC为 3.45 μg/mL,大肠杆菌、白地霉、巴氏醋酸杆菌MIC为6.9 μg/mL,禾谷镰孢菌、黄曲霉、假丝酵母MIC为 55.20 μg/mL,红酵母MIC为110.40μg/mL。  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