全文获取类型
收费全文 | 35637篇 |
免费 | 2293篇 |
国内免费 | 1418篇 |
专业分类
电工技术 | 1312篇 |
技术理论 | 7篇 |
综合类 | 4171篇 |
化学工业 | 5286篇 |
金属工艺 | 1393篇 |
机械仪表 | 2258篇 |
建筑科学 | 4652篇 |
矿业工程 | 1553篇 |
能源动力 | 1075篇 |
轻工业 | 2705篇 |
水利工程 | 1434篇 |
石油天然气 | 2531篇 |
武器工业 | 467篇 |
无线电 | 1749篇 |
一般工业技术 | 2708篇 |
冶金工业 | 2639篇 |
原子能技术 | 514篇 |
自动化技术 | 2894篇 |
出版年
2024年 | 74篇 |
2023年 | 352篇 |
2022年 | 672篇 |
2021年 | 893篇 |
2020年 | 1032篇 |
2019年 | 728篇 |
2018年 | 659篇 |
2017年 | 957篇 |
2016年 | 1124篇 |
2015年 | 1301篇 |
2014年 | 2513篇 |
2013年 | 1999篇 |
2012年 | 2707篇 |
2011年 | 2922篇 |
2010年 | 2272篇 |
2009年 | 2287篇 |
2008年 | 1923篇 |
2007年 | 2376篇 |
2006年 | 2291篇 |
2005年 | 1818篇 |
2004年 | 1517篇 |
2003年 | 1363篇 |
2002年 | 1054篇 |
2001年 | 898篇 |
2000年 | 720篇 |
1999年 | 536篇 |
1998年 | 428篇 |
1997年 | 291篇 |
1996年 | 255篇 |
1995年 | 197篇 |
1994年 | 159篇 |
1993年 | 122篇 |
1992年 | 103篇 |
1991年 | 67篇 |
1990年 | 84篇 |
1989年 | 60篇 |
1988年 | 53篇 |
1987年 | 34篇 |
1986年 | 33篇 |
1985年 | 23篇 |
1984年 | 45篇 |
1983年 | 18篇 |
1982年 | 19篇 |
1966年 | 25篇 |
1964年 | 21篇 |
1963年 | 18篇 |
1959年 | 30篇 |
1957年 | 17篇 |
1955年 | 23篇 |
1954年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
Presents an obituary for Hans Hermann Strupp, internationally acclaimed clinical psychologist and psychotherapy research pioneer, who died October 5, 2006, in Nashville, Tennessee, following a long struggle with Parkinson's disease. Hans Strupp elicited unusual respect across disciplines, including psychiatry and medicine, and across national boundaries in numerous countries. Hans was truly a person of great distinction; he brought honor to his friends, his discipline, his university, his nation, and his family. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
In its policy rationale for evidence-based practice in psychology (EBPP), the APA Presidential Task Force on Evidence-Based Practice (see record 2006-05893-001) claims to have constituted itself with "scientists and practitioners from a wide range of perspectives and traditions, reflecting the diverse perspectives within the field" (p. 273). We applaud this attention to diversity but contend that an entire perspective of the debate was omitted in the Task Force's newly approved policy and its underlying report. The failure to consider a philosophy of science perspective led the Task Force to make a number of epistemological assumptions that are not based on evidence or rationale and that thus violate the very spirit of evidence-based decision making. In this comment, we reveal a few of these assumptions and discuss their detrimental consequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Replies to comments by J. Read (see record 2007-07130-012), D. Gleaves et al (see record 2007-07130-013), V. Edwards et al (see record 2007-07130-014), M. Black and R. Black (see record 2007-07130-015), and S. Ullman (see record 2007-07130-016), which raised important points about the authors' original article (see record 2006-03947-003). Those comments extend our thinking about how to ask participants about abuse in an ethical way. Together, the comments point to the importance of researchers examining our own reasons for asking--or not asking--about abuse and of paying attention to how we respond when we ask. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
工业废水中金属离子对水环境造成污染,并危及人体健康,应准确进行测定.论述了原子吸收分光光度法测定工业废水中金属元素的原理,重点论述了测定Zn的条件、范围、干扰等因素,总结了测定锌的条件及测定结果;实验证明,用原子吸收分光光度法测定工业废水中的Zn元素,可取得较好的结果. 相似文献
86.
87.
朱颖 《湖南冶金职业技术学院学报》2004,(3)
从能力培养的角度较全面、系统地阐述了教师组织课堂教学的基本方法和手段。并针对职业教育的培养要求及学生的心理特点,在有效整合学校各种教学资源、努力实现学生知识结构与能力培养和谐统一方面进行了一些有益探索和实践。 相似文献
88.
梁昔明 《中南工业大学学报(英文版)》2005,12(1):93-96
An active set truncated-Newton algorithm (ASTNA) is proposed to solve the large-scale bound constrained sub-problems. The global convergence of the algorithm is obtained and two groups of numerical experiments are made for the various large-scale problems of varying size. The comparison results between ASTNA and the subspace limited memory quasi-Newton algorithm and between the modified augmented Lagrange multiplier methods combined with ASTNA and the modified barrier function method show the stability and effectiveness of ASTNA for simultaneous optimization of distillation column. 相似文献
89.
Timo Nurminen 《International Journal of Project Management》1985,3(3):163-168
When dealing with a Soviet client, tendering, scheduling, consideration of available resources, management responsibilities, start-up and hand-over must be approached from a slightly different angle than when dealing with Western clients. Aspects of project management from feasibility analysis to hand-over are described, based on the experience of a Finnish general contractor, Finn Stroi. 相似文献
90.