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   237篇
  免费   9篇
电工技术   2篇
化学工业   55篇
金属工艺   3篇
机械仪表   12篇
建筑科学   4篇
矿业工程   1篇
能源动力   7篇
轻工业   2篇
石油天然气   10篇
无线电   29篇
一般工业技术   55篇
冶金工业   46篇
原子能技术   9篇
自动化技术   11篇
  2023年   4篇
  2022年   26篇
  2021年   15篇
  2020年   7篇
  2019年   4篇
  2018年   5篇
  2017年   3篇
  2016年   4篇
  2015年   8篇
  2014年   5篇
  2013年   14篇
  2012年   7篇
  2011年   12篇
  2010年   6篇
  2009年   6篇
  2008年   10篇
  2007年   4篇
  2006年   5篇
  2004年   4篇
  2003年   3篇
  2002年   4篇
  2001年   2篇
  2000年   6篇
  1999年   3篇
  1998年   6篇
  1997年   10篇
  1996年   7篇
  1995年   8篇
  1994年   3篇
  1993年   3篇
  1992年   2篇
  1991年   2篇
  1990年   4篇
  1987年   3篇
  1983年   2篇
  1982年   1篇
  1980年   1篇
  1979年   1篇
  1978年   2篇
  1977年   1篇
  1976年   4篇
  1975年   2篇
  1974年   1篇
  1973年   2篇
  1972年   2篇
  1971年   1篇
  1970年   1篇
  1967年   1篇
  1964年   3篇
  1962年   2篇
排序方式: 共有246条查询结果,搜索用时 15 毫秒
1.
Theoretical Foundations of Chemical Engineering - On the basis of the classic concepts of the theory of solid-phase combustion, for the first time, a model with a detailed scheme of chemical...  相似文献   
2.
Ceria-based solid solutions are important materials for high- and medium-temperature electrochemical applications. However, the stabilities of both binary and ternary ceria-based solid solutions are insufficient at elevated temperatures, which limits their application as solid electrolytes or SOFC cathodes. Data on the high-temperature stability of ceria-based ceramics are unavailable in the literature. In the present study, we report a thermodynamic stability investigation of Y2O3-CeO2 and Y2O3-ZrO2-CeO2 solid solutions. The thermal prehistories of binary and ternary systems were investigated using STA, XRD, and ESCA techniques. The vaporization processes were investigated in the temperature range of 1577–2227°С via the Knudsen effusion mass spectrometry technique. Using data on the component activity in solid-phase thermodynamic properties of Y2O3-CeO2 solid solutions, which is represented as the Gibbs energy, the excess Gibbs energy was calculated as a function of the ceria mol. %. It was shown that the reduction of Ce4+ to Ce3+ in Y2O3-CeO2 and Y2O3-ZrO2-CeO2 solid solutions corresponds to less-negative Gibbs energy compared to ZrO2-CeO2 solid solutions.  相似文献   
3.
Multimedia Tools and Applications - The paper addresses the problem of human activity recognition based on the data from wearable sensors. Human activity recognition depends on a wide context of...  相似文献   
4.
5.
Subchronic intoxication was induced in outbred male rats by repeated intraperitoneal injections with lead oxide (PbO) and/or cadmium oxide (CdO) nanoparticles (NPs) 3 times a week during 6 weeks for the purpose of examining its effects on the contractile characteristics of isolated right ventricle trabeculae and papillary muscles in isometric and afterload contractions. Isolated and combined intoxication with these NPs was observed to reduce the mechanical work produced by both types of myocardial preparation. Using the in vitro motility assay, we showed that the sliding velocity of regulated thin filaments drops under both isolated and combined intoxication with CdO–NP and PbO–NP. These results correlate with a shift in the expression of myosin heavy chain (MHC) isoforms towards slowly cycling β–MHC. The type of CdO–NP + PbO–NP combined cardiotoxicity depends on the effect of the toxic impact, the extent of this effect, the ratio of toxicant doses, and the degree of stretching of cardiomyocytes and muscle type studied. Some indices of combined Pb–NP and CdO–NP cardiotoxicity and general toxicity (genotoxicity included) became fully or partly normalized if intoxication developed against background administration of a bioprotective complex.  相似文献   
6.
Instrumental support of scientific research and EMC tests are considered. Sample generators of field and conducted interferences of microsecond, nanosecond, and subnanosecond ranges are given. The structure of an optoelectronic electromagnetic field gage is described. Characteristics of TEM and GTEM chambers are given.  相似文献   
7.
8.
Listeria monocytogenes is an important food associated pathogen because of its relatively high heat resistance and ability to multiply in refrigeration temperatures. Its thermotolerance can be increased when its cells are subjected to heat shock. One- to eight-fold increase of D values of L. monocytogenes have been reported, depending on the heat shock duration, the temperature and the heating menstrum. This acquisition of heat tolerance is related to the induction of the synthesis of heat shock proteins (HSPs).The adaptive response of food pathogens has important consequences on the safety of thermally processed foods. It is believed that this is responsible for the frequent occurrence of deviations (tails and shoulders) during heat treatments that are observed in the exponential model of microbial inactivation. These deviations from log-linear kinetic especially encountered under mild heat treatments, mean that prediction of food safety can no longer rely upon D and z values. Adaptive response to heat must be considered when quantifying and modeling microbial inactivation during thermal processing in order to achieve microbiologically safe products without overly conservative heat processes. Therefore a more mechanistic approach is needed for more accurate predictions of thermal inactivation. Prerequisite to this model are thorough studies to understand how L. monocytogenes and other pathogens adapt their cellular physiology to overcome heat and other stresses.  相似文献   
9.
From position of the uniform concept of the accident medicine the problems of toxicological supply of the ships of MNF are considered. Peculiarities of chemical accidents in the ship conditions are marked. The question about principles of harmful chemical substances regulating, forming air environment of ship living quarters is discussed. The prospects of practical use of antidotal means, intended for protection of personnel from toxic action of carbon dioxide and chemical combinations, causing development of toxic edema of lungs are given.  相似文献   
10.
In a statistical setting of the classification (pattern recognition) problem the number of examples required to approximate an unknown labelling function is linear in the VC dimension of the target learning class. In this work we consider the question of whether such bounds exist if we restrict our attention to computable classification methods, assuming that the unknown labelling function is also computable. We find that in this case the number of examples required for a computable method to approximate the labelling function not only is not linear, but grows faster (in the VC dimension of the class) than any computable function. No time or space constraints are put on the predictors or target functions; the only resource we consider is the training examples. The task of classification is considered in conjunction with another learning problem - data compression. An impossibility result for the task of data compression allows us to estimate the sample complexity for pattern recognition.  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