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   1312篇
  免费   41篇
电工技术   10篇
综合类   2篇
化学工业   214篇
金属工艺   5篇
机械仪表   17篇
建筑科学   70篇
矿业工程   3篇
能源动力   13篇
轻工业   134篇
水利工程   23篇
石油天然气   3篇
无线电   100篇
一般工业技术   138篇
冶金工业   488篇
原子能技术   1篇
自动化技术   132篇
  2023年   6篇
  2022年   15篇
  2021年   24篇
  2020年   18篇
  2019年   15篇
  2018年   20篇
  2017年   20篇
  2016年   27篇
  2015年   24篇
  2014年   35篇
  2013年   69篇
  2012年   55篇
  2011年   75篇
  2010年   44篇
  2009年   32篇
  2008年   64篇
  2007年   57篇
  2006年   61篇
  2005年   41篇
  2004年   48篇
  2003年   37篇
  2002年   29篇
  2001年   24篇
  2000年   22篇
  1999年   23篇
  1998年   70篇
  1997年   34篇
  1996年   39篇
  1995年   23篇
  1994年   39篇
  1993年   22篇
  1992年   26篇
  1991年   6篇
  1990年   22篇
  1989年   16篇
  1988年   11篇
  1987年   11篇
  1986年   9篇
  1985年   13篇
  1984年   6篇
  1983年   13篇
  1982年   9篇
  1981年   12篇
  1980年   5篇
  1979年   11篇
  1978年   11篇
  1977年   12篇
  1976年   15篇
  1973年   6篇
  1970年   6篇
排序方式: 共有1353条查询结果,搜索用时 15 毫秒
1.
2.
Many engineering students enter and exit general chemistry courses with little appreciation of chemistry's relevance to other fields. At WPI many of these students go on to take introductory materials science and arrive with poor attitudes about chemistry and little retention of key concepts, but then become more engaged as they discover connections to engineering applications. Consequently, instructors in chemistry and mechanical engineering collaborated to augment general chemistry laboratories with explicit “bridges” to material properties and applications. Evaluation results showed that while students' attitudes toward chemistry were unaffected by bridging, particular aspects of the students' lab experience were enhanced to a statistically significant degree. Similar cross‐disciplinary collaborations might be considered elsewhere as a means of helping students find meaning and integrate subject matter, in a manner that is more feasible than large‐scale course or curriculum restructuring.  相似文献   
3.
Memory, suggestibility, stress arousal, and trauma-related psychopathology were examined in 328 3- to 16-year-olds involved in forensic investigations of abuse and neglect. Children's memory and suggestibility were assessed for a medical examination and venipuncture. Being older and scoring higher in cognitive functioning were related to fewer inaccuracies. In addition, cortisol level and trauma symptoms in children who reported more dissociative tendencies were associated with increased memory error, whereas cortisol level and trauma symptoms were not associated with increased error for children who reported fewer dissociative tendencies. Sexual and/or physical abuse predicted greater accuracy. The study contributes important new information to scientific understanding of maltreatment, psychopathology, and eyewitness memory in children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
5.
6.
Alzheimer's disease (AD) and Parkinson's disease (PD) impair working memory (WM). It is unclear, however, whether the deficits seen early in the course of these diseases are similar. To address this issue, the authors compared the performance of 22 patients with mild AD, 20 patients with early PD and without dementia, and 112 control participants on tests of inhibition, short-term memory, and 2 commonly administered tests of WM. The results suggest that although mild AD and early PD both impair WM, the deficits may be related to the interruption of different processes that contribute to WM performance. Early PD disrupted inhibitory processes, whereas mild AD did not. The WM deficits seen in patients with AD may be secondary to deficits in other cognitive capacities, including semantic memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Longitudinal analyses on normal versus impaired functioning across 7 domains were conducted in children who had experienced profound institutional deprivation up to the age of 42 months and were adopted from Romania into U.K. families. Comparisons were made with noninstitutionalized children adopted from Romania and with nondeprived within-U.K. adoptees placed before the age of 6 months. Specifically, the validity of the assessment, the degree of continuity and change in levels of functioning from 6 to 11 years, and the factors in the pre- and postadoption environment accounting for heterogeneity in outcome were examined. Pervasive impairment was significantly raised in children experiencing institutional deprivation for ≥6 months of life, with a minority within this group showing no impairment. There was no additional significant effect of duration of deprivation beyond the 6-month cutoff, and few other predictors explained outcome. The pattern of normality/impairment was mainly established by 6 years of age, with considerable continuity at the individual level between 6 and 11 years. The findings are discussed in terms of the possibility of a sensitive period for development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Attempting to understand and predict weather on a local and global basis has challenged both the scientific and engineering communities. One key parameter in understanding the weather is the ocean surface wind vector because of its role in the energy exchange at the air-sea surface. scatterometers, radars that measure the reflectivity of a target offer a tool with which to remotely monitor these winds from tower-, aircraft-, and satellite-based platforms. This paper introduces three current airborne scatterometer systems, and presents data collected by these instruments under low-, moderate-, and high-wind conditions. The paper focuses on airborne scatterometers because of their ability to resolve submesoscale variations in wind fields. Discrepancies between existing theory and the observations are noted and the concerns in measuring low-wind speeds discussed. Finally, the application of using this technology for estimating the surface-wind vector during a hurricane is demonstrated  相似文献   
9.
Schools often use peer-tutoring as a corrective program for students who are experiencing difficulties academically. Given appropriate behavioral structure, peer-tutoring can become a powerful classwide instructional intervention. An historical perspective on the use of students as teachers for their peers is given in this selective literature review. Also, information on the efficacy of considering behavioral function and structure and data addressing ecobehavioral variables to establish a productive learning environment are provided. The authors emphasize infusing peer-tutoring programs with applied behavior analysis techniques to increase the academic success of large numbers of students cost effectively. Peer-tutoring programs are considered to be a way for applied behavior analysts to gain greater access to American school learning environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
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