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   28338篇
  免费   3112篇
  国内免费   1426篇
电工技术   2813篇
技术理论   8篇
综合类   3079篇
化学工业   1538篇
金属工艺   370篇
机械仪表   793篇
建筑科学   4857篇
矿业工程   1200篇
能源动力   1396篇
轻工业   2281篇
水利工程   2548篇
石油天然气   1138篇
武器工业   400篇
无线电   1274篇
一般工业技术   2332篇
冶金工业   2065篇
原子能技术   430篇
自动化技术   4354篇
  2024年   144篇
  2023年   449篇
  2022年   912篇
  2021年   1165篇
  2020年   1139篇
  2019年   940篇
  2018年   989篇
  2017年   991篇
  2016年   1382篇
  2015年   1224篇
  2014年   2136篇
  2013年   2399篇
  2012年   2175篇
  2011年   2369篇
  2010年   1789篇
  2009年   1769篇
  2008年   1641篇
  2007年   1780篇
  2006年   1688篇
  2005年   1208篇
  2004年   981篇
  2003年   814篇
  2002年   640篇
  2001年   442篇
  2000年   318篇
  1999年   249篇
  1998年   213篇
  1997年   146篇
  1996年   133篇
  1995年   87篇
  1994年   92篇
  1993年   60篇
  1992年   46篇
  1991年   42篇
  1990年   40篇
  1989年   42篇
  1988年   38篇
  1987年   25篇
  1986年   23篇
  1985年   15篇
  1984年   19篇
  1983年   16篇
  1982年   15篇
  1981年   8篇
  1980年   9篇
  1979年   7篇
  1965年   15篇
  1963年   5篇
  1961年   6篇
  1959年   5篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Risk factors affecting the course of posttraumatic stress disorder (PTSD) are poorly understood. As part of a larger study on characterizing exposure to herbicides in Vietnam, the authors investigated this issue in a random sample of 1,377 American Legionnaires who had served in Southeast Asia during the Vietnam War and were followed over a 14-year period. High combat exposure, perceived negative community attitudes at homecoming, minority race, depression symptoms at Time 1, and more anger at Time 1 predicted a more chronic course. Community involvement at Time 1 was protective and associated with decreased risk at Time 2. Discomfort in disclosing Vietnam experiences was associated with an increased risk for developing PTSD but did not predict its course. Combat exposure predicted PTSD course more strongly than any other risk factor. Findings suggest recovery from PTSD is significantly influenced by perceived social support. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
Reviews the book, The achievement test desk reference: A guide to learning disability identification, second edition by Dawn P. Flanagan, Samuel O. Ortiz, Vincent C. Alfonso, and Jennifer T. Mascolo (2006). The Second Edition of the Achievement test desk reference comes only four years after its first edition. Its content echoes the first edition, with the chapters now re-organized and updated. However, this edition is also timely; its significant contributions are its theoretical and practical model for defining and assessing learning disabilities (LD) and its update of practical information for interpreting many of the new standardized achievement tests. The goal for this edition was to provide an integrated and systematic framework for achievement testing within the framework of the Cattell-Horn-Carroll (CHC) theory of human cognitive abilities and the Response to Intervention (RTI) movement. Part 1 of provides an update of the theories, definitions, assessment, interpretation, and identification of LD. Part 2 describes and reviews the psychometric, theoretical, and qualitative features of achievement tests published between 1996 and 2006 and normed on people from the United States. Part 3 provides a comprehensive, step-by-step process for assessing learning disabilities under the Individuals with Disabilities Education Improvement Act (IDEA 2004). This volume guides practitioners to choose the best achievement tests to use. It shows how to get the most efficient and effective evaluations of students' academic skills that could account for their difficulties and possible learning disabilities. This book will be essential reference material for effective LD assessments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
There is a growing trend of research in neuropsychological assessment in Asia: The mean number of published studies increased from 1.8 in the 1980s to 16.0 in 2 recent years. About 40% of the studies reviewed concerned test development or adaptation, with the latter greatly outnumbering the former. To facilitate the test selection for clinical use, 36 clinical measures were evaluated based on some statistical criteria. The results showed that only 8 neuropsychological tests (5 Chinese. 2 Korean, and 1 Japanese) met the criteria. Given that Asian and Western populations differ on certain cognitive processes, future development of neuropsychological assessment measures in Asia should move from the adaptation of Western tests toward the construction of original tests with better ecological validity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
94.
潘凤丽  刘峰 《有色矿冶》2003,19(3):63-65
针对目前大多数科研单位在内部会计控制中存在的问题,探讨了科研单位在转制过程中应如何建立和完善内部会计控制制度,以达到防范经营风险,保护资产安全、完整,促进单位经营管理目标和政策有效实施。  相似文献   
95.
96.
管道完整性管理标准及其支持体系   总被引:4,自引:0,他引:4  
王弢  帅健 《天然气工业》2006,26(11):126-129
通过对美国管道完整性管理标准ASME B31.8S和API 1160内容的论述,总结了管道完整性管理标准的3个特点:①管道完整性管理标准是一种过程标准;②管道完整性管理标准提供了一种管道运行管理的模式和理念,反映了当前管道安全管理从单一安全目标发展到优化、增效、提高综合经济效益的多目标趋向;③完整性管理是以管道安全为目标的系统管理体系,管道完整性管理标准是一种体系规范。从管道完整性管理系统的角度,列举了美国管道完整性管理的主要支持性标准、规范和法律文件。最后对国内管道完整性管理研究提出了建议。  相似文献   
97.
本分析了高职院的发展环境及负债情况,对高职院负债融资引起的财务风险的涵义、影响财务风险的因素进行了探讨,并提出了防范财务风险的策略。  相似文献   
98.
The ability to accurately and reliably predict whether an older adult will commit suicide has eluded clinicians and researchers. A random national sample of psychologists who work with older adults was surveyed regarding their perception of 36 risk factors for completed suicide and indirect self-destructive behavior in older adults. This study produced a profile of psychologists' assessment and treatment practices when working with suicidal older adults. Determining what psychologists consider to be the most salient risk factors for completed suicide is important in identifying a minimum standard that clinicians should follow when assessing older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
Skill and risk taking are argued to be independent and to require different remedial programs. However, it is possible to contend that skill-based training could be associated with an increase, a decrease, or no change in risk-taking behavior. In 3 experiments, the authors examined the influence of a skill-based training program (hazard perception) on the risk-taking behavior of car drivers (using video-based driving simulations). Experiment 1 demonstrated a decrease in risk taking for novice drivers. In Experiment 2, the authors examined the possibilities that the skills training might operate through either a nonspecific reduction in risk taking or a specific improvement in hazard perception. Evidence supported the latter. These findings were replicated in a more ecological context in Experiment 3, which compared advanced and nonadvanced police drivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
张祥彬 《水力发电》2006,32(12):97-99
安全性评价是一种现代化的管理手段。开展安全性评价可以提高水电站的安全生产管理水平和设备安全稳定运行水平。结合工作实践,介绍了周宁水电站安全性评价工作的实施过程、主要措施和取得的初步成效。  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