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   243篇
  免费   4篇
电工技术   1篇
综合类   1篇
化学工业   29篇
金属工艺   1篇
机械仪表   1篇
建筑科学   1篇
能源动力   7篇
轻工业   24篇
无线电   5篇
一般工业技术   26篇
冶金工业   126篇
自动化技术   25篇
  2022年   1篇
  2021年   3篇
  2020年   2篇
  2019年   2篇
  2018年   3篇
  2017年   2篇
  2016年   2篇
  2015年   2篇
  2014年   1篇
  2013年   5篇
  2012年   4篇
  2011年   9篇
  2010年   6篇
  2009年   10篇
  2008年   8篇
  2007年   9篇
  2006年   12篇
  2005年   8篇
  2004年   8篇
  2003年   4篇
  2002年   8篇
  2001年   12篇
  2000年   7篇
  1999年   5篇
  1998年   24篇
  1997年   11篇
  1996年   8篇
  1995年   3篇
  1994年   6篇
  1993年   7篇
  1992年   3篇
  1991年   1篇
  1990年   1篇
  1989年   5篇
  1987年   4篇
  1986年   5篇
  1985年   2篇
  1984年   8篇
  1983年   2篇
  1982年   3篇
  1981年   5篇
  1980年   2篇
  1979年   1篇
  1978年   2篇
  1977年   2篇
  1976年   4篇
  1973年   1篇
  1972年   1篇
  1971年   1篇
  1961年   1篇
排序方式: 共有247条查询结果,搜索用时 31 毫秒
1.
2.
On the basis of the behavioral approach system (BAS) dysregulation theory of bipolar disorder, this study examined the relation between occurrence of a BAS activation-relevant life event--goal striving--and onset of hypomanic and depressive episodes and symptoms. In particular, the authors examined the relation between preparing for and completing final exams (a goal-striving event) and onset of bipolar spectrum episodes and symptoms in college students with bipolar II disorder or cyclothymia (i.e., "soft" bipolar spectrum conditions). One hundred fifty-nine individuals with either a bipolar spectrum disorder (n=68) or no major affective psychopathology (controls; n=91) were further classified on the basis of whether they were college students (i.e., completed final exams). Consistent with the BAS dysregulation theory, preparing for and completing final exams was associated with an increase in hypomanic but not depressive episodes and symptoms in individuals with a soft bipolar spectrum diagnosis. Furthermore, self-reported BAS sensitivity moderated the presence of certain hypomanic symptoms during final exams. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Thin-film nickel coatings on fiber materials   总被引:1,自引:0,他引:1  
Vacuum deposition of thin films onto fiber materials is a promising method of obtaining electromagnetic screens. We have studied the structure and the electromagnetic properties of machine-knitted fabric coated with nickel by means of magnetron sputtering. When the fabric is irradiated from the metal-coated side, the reflection coefficient is higher by a factor of 1.4 as compared to the case when the same source of electromagnetic radiation is situated on the opposite side (facing the uncoated surface), while the absorption coefficient in both cases is the same.  相似文献   
4.
Readers' eye movements were monitored as they read sentences containing lexically ambiguous words. The ambiguous words were either biased (one strongly dominant interpretation) or nonbiased. Readers' gaze durations were longer on nonbiased than biased words when the disambiguating information followed the target word. In Experiment 1, reading times on the disambiguating word did not differ whether the disambiguation followed the target word immediately or occurred several words later. In Experiment 2, prior disambiguation eliminated the long gaze durations on nonbiased target words but resulted in long gaze durations on biased target words if the context demanded the subordinate meaning. The results indicate that successful integration of one meaning with prior context terminates the search for alternative meanings of that word. This results in selective (single meaning) access when integration of a dominant meaning is fast (due to a biasing context) and identification of a subordinate meaning is slow (a strongly biased ambiguity with low-frequency meaning). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Court cases of recovered memories of childhood abuse, in which the victim's testimony may constitute the only evidence available, and a growing body of research demonstrating the inexactitude and suggestibility of autobiographical memory of long past events, are forcing courts and cognitive scientists to seek scientific, principled criteria for admissibility of such testimony. The authors use as examples 2 recent court cases. In the 1st case, a concussion produced total retrograde amnesia for an accident for a period of 3 years, and then, over a few months, the driver claimed his memory returned. In the 2nd, 2 adults reported to the police that they witnessed their sister's murder 35 years earlier, when they were 3 and 5 years old, respectively. The authors provide objective guidelines for courts to determine whether testimony about recovered or very-long-term memory for eyewitnessed events should be admissible. The principles outlined can be expanded easily to include eyewitness testimony in general. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
The turbulence in the upward gas flow above a gas-fluidised bed was measured by hot wire anemometry. In this region above the bed—defined as the free is the fluidising velocity. The irregularity of the motion is caused by bursting bubbles at the surface of the bed. It appears that the gas within a bu are termed “ghost bubbles”.Ghost bubble mechanics were studied by releasing single bubbles from: (i) stagnant liquid; and (ii) an incipiently fluidised bed. Tle velocity field wa The velocity of a ghost bubble diminishes as it rises, due to fluid entrainment caused by turbulent circulatory flow within the bubble.From the freeboard turbulence measurements for a continuously bubbling fluidised bed, it is clear that the turbulence is due to ghost bubbles, but the ghost bubble.  相似文献   
7.
Paterson LJ  Weselake RJ  Mir PS  Mir Z 《Lipids》2002,37(6):605-611
The content and positional distribution of CLA in TAG fractions of lamb tissues was examined with either preformed CLA or the linoleic acid precursor of CLA in the diet as experimental treatments. The CLA content of phospholipid (PL) from these tissues was also examined. Thirteen lambs were randomized to the following dietary treatments: (i) control diet (no supplement); (ii) CLA supplementation (0.33 g d−1 for 21 d prior to weaning) to milk-replacer of pre-ruminating lambs, or (iii) feeding linoleic acid-rich oil (6% safflower oil on a dry matter basis) to weaned ruminating lambs. At slaughter, tissue samples were procured from diaphragm, rib muscle, and subcutaneous (SC) adipose tissue. Safflower oil supplementation in the diet resulted in an increase in CLA content of the TAG from diaphragm, rib muscle, and SC adipose tissue by about threefold (P<0.05) on a mol% basis. CLA was localized to the sn-1/3 positions of TAG. Animals that received pre-formed CLA, however, had increased proportions of CLA at the sn-2 position of TAG from SC adipose tissue, suggesting that there were tissue-specific dietary effects and possible age-related effects on the mode of FA incorporation into TAG. Safflower oil supplementation in the diet had no effect on the CLA content of PL from diaphragm, rib muscle, and SC adipose tissue, suggesting that CLA was preferentially incorporated into the TAG of these tissues.  相似文献   
8.
Except for a variation in the freeepsilon-amino lysine content of the protein, the Mexican screw-pressed meals were quite similar in their composition. The lysine values for sesame protein obtained for the solvent-extracted meals were much higher than those obtained for the screw-pressed meals. Screening of the endosperm and spermoderm from the solvent-extracted meals was effective in reducing the oxalate content of the resulting flour although some epiderm fragments passed through a 60-mesh screen. The decortication process completely removed the portion containing the oxalate from the seed and also reduced the calcium, sugar, and silica contents. Presented at the annual meeting, American Oil Chemists' Society, Dallas, Tex., April 4–6, 1960. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U.S. Department of Agriculture.  相似文献   
9.
Hazard perception is one of the most important facets of driving and if the appropriate diagnostic tool is used it can discriminate between novice and experienced drivers. In this study video clips of actual driving scenarios were shown to novice and experienced drivers. The clips were stopped just prior to hazard onset and either the screen went black or the final still image stayed on the screen. Participants were then asked five questions about what happened next. This variant of the hazard perception test allowed the influence of processing time to be included and the level of situation awareness to be measured. Experienced drivers significantly anticipated more correct hazardous outcomes than novice drivers when the screen went black. Novice drivers benefited from the extra processing time afforded by the image remaining on the screen and significantly anticipated more hazards when the image remained on the screen than when it went black. The findings indicate that when processing time is manipulated, hazard perception accuracy reveals experiential differences. These differences are discussed with reference to hazard perception and situation awareness. This research informs the current controversy over whether hazard perception is a good diagnostic tool for driving performance. It identifies potential confounds in previous work and demonstrates that experiential differences can be found if the appropriate tests are used. Further, it suggests improvements for new hazard perception tests.  相似文献   
10.
Universal Access in the Information Society - In recent years, researchers have attempted to shift patient decision aids (PDAs) from paper-based to web-based to increase its accessibility. Insulin...  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