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   75篇
  免费   2篇
化学工业   27篇
机械仪表   2篇
建筑科学   1篇
矿业工程   1篇
能源动力   3篇
轻工业   9篇
无线电   4篇
一般工业技术   9篇
冶金工业   11篇
自动化技术   10篇
  2023年   3篇
  2022年   6篇
  2021年   6篇
  2020年   1篇
  2019年   5篇
  2018年   2篇
  2017年   3篇
  2016年   6篇
  2015年   2篇
  2014年   1篇
  2013年   3篇
  2012年   2篇
  2011年   5篇
  2010年   2篇
  2009年   2篇
  2008年   2篇
  2006年   3篇
  2005年   3篇
  2004年   5篇
  2003年   3篇
  2000年   1篇
  1997年   1篇
  1996年   3篇
  1995年   1篇
  1994年   2篇
  1981年   1篇
  1978年   1篇
  1974年   2篇
排序方式: 共有77条查询结果,搜索用时 15 毫秒
71.
We describe a compact luminescent gaseous oxygen (O2) sensor microsystem based on the direct integration of sensor elements with a polymeric optical filter and placed on a low power complementary metal-oxide semiconductor (CMOS) imager integrated circuit (IC). The sensor operates on the measurement of excited-state emission intensity of O2-sensitive luminophore molecules tris(4,7-diphenyl-1,10-phenanthroline) ruthenium(II) ([Ru(dpp)3]2+) encapsulated within sol-gel derived xerogel thin films. The polymeric optical filter is made with polydimethylsiloxane (PDMS) that is mixed with a dye (Sudan-II). The PDMS membrane surface is molded to incorporate arrays of trapezoidal microstructures that serve to focus the optical sensor signals on to the imager pixels. The molded PDMS membrane is then attached with the PDMS color filter. The xerogel sensor arrays are contact printed on top of the PDMS trapezoidal lens-like microstructures. The CMOS imager uses a 32 × 32 (1024 elements) array of active pixel sensors and each pixel includes a high-gain phototransistor to convert the detected optical signals into electrical currents. Correlated double sampling circuit, pixel address, digital control and signal integration circuits are also implemented on-chip. The CMOS imager data is read out as a serial coded signal. The CMOS imager consumes a static power of 320 μW and an average dynamic power of 625 μW when operating at 100 Hz sampling frequency and 1.8 V DC. This CMOS sensor system provides a useful platform for the development of miniaturized optical chemical gas sensors.  相似文献   
72.
Multiwalled carbon nanotubes were synthesized using Ni–Mo–Mg oxide catalyst prepared by sol–gel technique. Carbon nanotubes were formed in situ by the reduction of nickel oxide (NiO) and molybdenum oxide (MoO3) to Ni and Mo by a gas mixture of nitrogen, hydrogen and cyclohexane at 750 °C. Scanning Electron Microscopy (SEM) was used to confirm the formation of carbon nanotubes (CNTs). The pore size distribution of carbon nanotubes (CNTs) was investigated by N2 adsorption and desorption. It was found that the pore size fell into the mesopore range: 2 < d < 50 nm. Interpretation was also made using Raman spectroscopy, Diffuse reflectance spectroscopy, X-ray diffraction and ESR spectra. This method is found to produce a very high yield weighing over 20 times of the catalyst. Based on the experimental conditions and results obtained a possible growth mechanism of the carbon nanotubes is proposed.  相似文献   
73.
Wheat is an important staple food globally, providing a significant contribution to daily energy, fiber, and micronutrient intake. Observational evidence for health impacts of consuming more whole grains, among which wheat is a major contributor, points to significant risk reduction for diabetes, cardiovascular disease, and colon cancer. However, specific wheat components may also elicit adverse physical reactions in susceptible individuals such as celiac disease (CD) and wheat allergy (WA). Recently, broad coverage in the popular and social media has suggested that wheat consumption leads to a wide range of adverse health effects. This has motivated many consumers to avoid or reduce their consumption of foods that contain wheat/gluten, despite the absence of diagnosed CD or WA, raising questions about underlying mechanisms and possible nocebo effects. However, recent studies did show that some individuals may suffer from adverse reactions in absence of CD and WA. This condition is called non‐celiac gluten sensitivity (NCGS) or non‐celiac wheat sensitivity (NCWS). In addition to gluten, wheat and derived products contain many other components which may trigger symptoms, including inhibitors of α‐amylase and trypsin (ATIs), lectins, and rapidly fermentable carbohydrates (FODMAPs). Furthermore, the way in which foods are being processed, such as the use of yeast or sourdough fermentation, fermentation time and baking conditions, may also affect the presence and bioactivity of these components. The present review systematically describes the characteristics of wheat‐related intolerances, including their etiology, prevalence, the components responsible, diagnosis, and strategies to reduce adverse reactions.  相似文献   
74.
Jacobs  Daisy  Ingwersen  Peter 《Scientometrics》2000,47(1):75-93
The paper is a bibliometric study of the publication patterns and impact of South African scientists 1981–96, with special emphasis on the period 1992–96. The subject fields surveyed are Physics; Chemistry, Plant and Animal Sciences; and Biochemistry/Microbiology. Scientists were selected from the ten universities of the Eastern Cape, Western Cape and KwaZulu Natal, which vary considerably, with respect to standards of education, quantity of publications, development and overall progress. The general purpose is two-fold: 1) to observe the publication and citation trends during 1981–96, a period which covers significant policy changes in the country, in particular the end of apartheid 1994; within this context 2) to investigate the patterns used by scientists 1992–96 from these different institutions in publishing the results of their research in the form of conference papers or (inter)national journals. The study collected two sets of data through a scientometric analysis of Science Citation Index and a questionnaire. With the exception of Physics, the results demonstrate a decreasing South African world share, in particular for Plant & Animal Sc. publications, and a similar decline of citations starting in 1986/87. Further, the citation impact relative to the world, after a substantial drop 1985–93 probably representing the international embargo period, in 1994–96 reaches the same level as observed in 1985–89. Also, the study shows that there is a direct relation between academic position, research experience and productivity among South African Scientists in the four scientific disciplines.  相似文献   
75.
76.

Scope

Western type of diets are characterized by high animal protein intake and are associated with various chronic inflammatory diseases. With a higher protein consumption, excess undigested protein will reach the colon and be subsequently metabolized by gut microbiota. Depending on the type of protein, fermentation in the colon generates different metabolites with varying biological effects. This study aims to compare the impact of protein fermentation products from different sources on gut health.

Methods and results

Three high protein diets (vital wheat gluten [VWG], lentil, or casein) are submitted to the in vitro model of colon. Fermentation of excess lentil protein for 72 h results in highest production of short-chain fatty acids and lowest production of branched-chain fatty acids. Exposure of Caco-2 monolayers or Caco-2 monolayers co-cultured with THP-1 macrophages to luminal extracts of fermented lentil protein results in less cytotoxicity of Caco-2 monolayers and less damage to barrier integrity, when compared to VWG and casein. Lowest induction of interleukin-6 is observed in THP-1 macrophages after treatment with lentil luminal extracts, which is identified to be regulated by aryl hydrocarbon receptor signaling.

Conclusion

The findings indicate that protein sources affect the health effects of high protein diet in the gut.  相似文献   
77.
International Journal of Information Security - Intrusion detection systems (IDS) identify cyber attacks given a sample of network traffic collected from real-world computer networks. As a powerful...  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