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   56篇
  免费   6篇
  国内免费   3篇
综合类   2篇
化学工业   4篇
金属工艺   3篇
机械仪表   13篇
建筑科学   2篇
矿业工程   1篇
能源动力   2篇
轻工业   12篇
石油天然气   2篇
武器工业   1篇
无线电   6篇
一般工业技术   4篇
冶金工业   2篇
自动化技术   11篇
  2021年   2篇
  2020年   2篇
  2018年   1篇
  2017年   3篇
  2016年   1篇
  2015年   1篇
  2014年   2篇
  2013年   3篇
  2012年   3篇
  2011年   6篇
  2010年   7篇
  2009年   2篇
  2008年   6篇
  2007年   8篇
  2006年   2篇
  2004年   3篇
  2003年   3篇
  2002年   1篇
  2001年   2篇
  2000年   1篇
  1999年   1篇
  1997年   2篇
  1995年   1篇
  1993年   2篇
排序方式: 共有65条查询结果,搜索用时 15 毫秒
1.
Blood has traditionally been used as a high protein ingredient in both human food and animal feed, with resulting economic, environmental and nutritional benefits. However, potentially serious health and safety issues related to blood consumption, particularly the risk of pathogenic or harmful metabolic materials, the infectivity of prion diseases, and the presence of identified allergens such as bovine serum albumin (BSA), are causing many consumers to shy away from any product containing either animal blood or ingredients derived from animal blood. Thus, despite the significant volumes of blood produced by slaughterhouses, blood is currently underutilized as a food ingredient. This article reviews the use of animal blood as an ingredient in food intended for human consumption or for animal feed and discusses the related consumer concerns.  相似文献   
2.
After the Bovine Spongiform Encephalopathy (BSE) crisis emerged in 1985/1986, all processed animal proteins (PAPs) were finally banned for use in animal feed in the European Union. To partially lift this feed ban, paths for re-introduction of PAPs from species other than ruminants e.g. pig and poultry, are described in the Transmissible Spongiform Encephalopathies (TSE) Roadmap 2. Cannibalism, however, is still not allowed. Specific detection methods for pig and poultry meal and PAPs are prerequisites for reintroduction of pig and poultry processed animal proteins into animal feed. Developing a sensitive PCR method that specifically detects the taxonomically diverse and therefore artificial group ‘poultry’ and that does not detect other birds at the same time is a challenge. Here, a novel TaqMan PCR method for poultry detection is presented. The specificity of the poultry method against target and non-target species has been extensively investigated. The efficiency, linearity and sensitivity was tested using dilution series of chicken, turkey, duck and goose DNA isolated from meat and autoclaved meat as a model system for PAPs.  相似文献   
3.
在KYKY-1000B扫描电镜上进行X射线能谱分析时,常出现附加的铁峰。本文从理论上对产生附加铁峰的原因作出了解释,并推导出附加铁峰强度和样品原子序数的函数关系的解析表达式,同时对附加的铁的百分含量进行了实验测量。由实验数据拟合得出的实验曲线和理论分析得出的表达很好地符合。  相似文献   
4.
Slate is a fine-grained, low-grade metamorphic rock derived from argillaceous sediments or occasionally volcanic ash. Although most slates contain mainly quartz, chlorite and white mica, they vary considerably in their durability, some lasting centuries while others fail after a few years of service. A detailed characterisation of their mineralogy is required for the assessment of performance, and to establish the provenance of a used slate. A combination of methods was used to examine Ballachulish slates; XRD analysis to determine the principal minerals present, XRF analysis to determine the total chemical composition, and scanning electron microscopy to determine the chemical composition of individual minerals. It was found that the white mica in Ballachulish slate is phengite and the chlorite is ripidolite. Feldspar is present as albite and carbonate as ferroan dolomite. Several accessory minerals were also identified, including chloritoid, monzonite and zircon. There was considerable variation in the ratio of the principal minerals, making it impossible to identify used slates by this criterion. Instead, chemical composition of the individual minerals, and possibly key accessory minerals, should be used to determine the provenance of slates.  相似文献   
5.
Bovine spongiform encephalopathy (BSE), or ‘mad cow disease’, is one of several transmissable spongiform encephalopathies (TSEs) known to affect certain mammals and is spread through the ingestion of infected animal tissue. It is believed that the inadvertent contamination of meat and bone meal (MBM) with infected animal tissue and the subsequent use of this material as a feed supplement contributed to the spread of the disease in cattle. As a result, the use of processed animal proteins (PAPs) in animal feeds is regulated in many parts of the world. Although feed testing is the only definitive means to certify compliance, regulatory compliance often relies solely on paper certification. Recently, rapid methods have become available that can be used by regulators to determine compliance during routine inspections. We describe a rapid, immunochromatographic strip test that can detect 0.1% MBM in animal feed. The test takes 15 min to perform and large numbers of samples can be screened for PAPs simultaneously.  相似文献   
6.
介绍了一种在CPM系统中适用的均衡方案,判决反馈均衡(DFE)的原理,并通过MATLAB仿真对该方案和线性均衡(LE)的优缺点进行了比较,最后给出了该种均衡方法在DSP中的实现方案,在此基础上选择了一种针对CPM系统实用的均衡系统。  相似文献   
7.
仿真结果评估组件设计与实现   总被引:1,自引:0,他引:1  
李权  李群  王维平  朱一凡 《计算机仿真》2003,20(12):24-26,120
该文主要介绍了空军战役过程推演仿真系统中的仿真结果评估组件的设计和实现,重点介绍了它的层次化的评估过程和系统的功能组成,并实现了系统开发,具有操作使用简单、评估结果可靠性高的特点。  相似文献   
8.
欠定和非完全稀疏性的盲信号提取   总被引:6,自引:5,他引:1       下载免费PDF全文
谢胜利  孙功宪  肖明  傅予力  吕俊 《电子学报》2010,38(5):1028-1031
两步策略已成为欠定盲信号分离的基本方法,混叠矩阵的估计是源恢复的先决条件.本文针对非完全稀疏性情况,提出一个两步的盲提取方法.该方法先利用信号的单源区间样本,估计部分源的基矢量(混叠矩阵的列矢量),后最小干扰地提取所对应的源;除它所对应的基矢量外,它不依赖的其它的基矢量,故回避了混叠矩阵可识别的必要条件.几个仿真实验结果显示了该算法的性能和实用性.  相似文献   
9.
The effects of fucose-containing sulfated polysaccharides, ascophyllan and fucoidan, isolated from the brown alga Ascophyllum nodosum, on the growth of various cell lines (MDCK, Vero, PtK1, CHO, HeLa, and XC) were investigated. In a colony formation assay, ascophyllan and fucoidan showed potent cytotoxic effects on Vero and XC cells, while other cell lines were relatively resistant to these polysaccharides. Almost no significant effects of these polysaccharides were observed in the cell lines tested using the Alamar blue cytotoxicity assay over 48 h with varying initial cell densities (2500–20,000 cells/well) in growth medium. Interestingly, a significant growth promoting effect of ascophyllan on MDCK cells was observed, whereas treatment with fucoidan showed growth suppressive effects on this cell line under the same experimental conditions. These results suggest that ascophyllan is distinguishable from fucoidan in terms of their bioactivities. This is the first report of the growth promoting effects of a sulfated fucan on a mammalian cell line under normal growth conditions.  相似文献   
10.
We report the development of an adaptive, multi-parameter battery state estimator based on the direct solution of the differential equations that govern an equivalent circuit representation of the battery. The core of the estimator includes two sets of inter-related equations corresponding to discharge and charge events respectively. Simulation results indicate that the estimator gives accurate prediction and numerically stable performance in the regression of model parameters. The estimator is implemented in a vehicle-simulated environment to predict the state of charge (SOC) and the charge and discharge power capabilities (state of power, SOP) of a lithium ion battery. Predictions for the SOC and SOP agree well with experimental measurements, demonstrating the estimator's application in battery management systems. In particular, this new approach appears to be very stable for high-frequency data streams.  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