全文获取类型
收费全文 | 30324篇 |
免费 | 1989篇 |
国内免费 | 1235篇 |
专业分类
电工技术 | 563篇 |
技术理论 | 4篇 |
综合类 | 8487篇 |
化学工业 | 3393篇 |
金属工艺 | 867篇 |
机械仪表 | 938篇 |
建筑科学 | 3699篇 |
矿业工程 | 473篇 |
能源动力 | 222篇 |
轻工业 | 1840篇 |
水利工程 | 735篇 |
石油天然气 | 1128篇 |
武器工业 | 479篇 |
无线电 | 2141篇 |
一般工业技术 | 1408篇 |
冶金工业 | 2009篇 |
原子能技术 | 97篇 |
自动化技术 | 5065篇 |
出版年
2024年 | 157篇 |
2023年 | 394篇 |
2022年 | 665篇 |
2021年 | 919篇 |
2020年 | 895篇 |
2019年 | 633篇 |
2018年 | 541篇 |
2017年 | 615篇 |
2016年 | 816篇 |
2015年 | 978篇 |
2014年 | 1973篇 |
2013年 | 1626篇 |
2012年 | 2119篇 |
2011年 | 2356篇 |
2010年 | 2238篇 |
2009年 | 2153篇 |
2008年 | 1864篇 |
2007年 | 2008篇 |
2006年 | 1864篇 |
2005年 | 1602篇 |
2004年 | 1330篇 |
2003年 | 1323篇 |
2002年 | 1130篇 |
2001年 | 714篇 |
2000年 | 643篇 |
1999年 | 441篇 |
1998年 | 227篇 |
1997年 | 177篇 |
1996年 | 135篇 |
1995年 | 129篇 |
1994年 | 111篇 |
1993年 | 92篇 |
1992年 | 92篇 |
1991年 | 63篇 |
1990年 | 51篇 |
1989年 | 43篇 |
1988年 | 40篇 |
1987年 | 36篇 |
1986年 | 23篇 |
1985年 | 24篇 |
1984年 | 30篇 |
1983年 | 21篇 |
1982年 | 29篇 |
1981年 | 13篇 |
1960年 | 11篇 |
1958年 | 11篇 |
1957年 | 24篇 |
1956年 | 14篇 |
1955年 | 25篇 |
1954年 | 16篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
在对影响体育教学质量的几种环境因素分析的基础上,提出了克服体育实践教学环境 因素的消极影响的主要措施以及正确利用这些物理因素的积极作用。 相似文献
43.
HHD型核子秤电离室已成功地使用于HCS型核子秤.对它的各种物理性能指标进行了检测,各项性能指标都达到了设计要求。 相似文献
44.
45.
This paper describes how SWoRD (scaffolded writing and rewriting in the discipline), a web-based reciprocal peer review system, supports writing practice, particularly for large content courses in which writing is considered critical but not feasibly included. To help students gain content knowledge as well as writing and reviewing skills, SWoRD supports the whole cycle of writing, reviews, back-reviews, and rewriting by scaffolding the journal publication process as its authentic practice model. In addition, SWoRD includes algorithms that compute individual reviewer’s review accuracy, which is in turn used to support the various drawbacks of reciprocal peer reviews (e.g., variation in motivation or ability of reviewers). Finally, this paper describes an empirical evaluation showing that the SWoRD approach is effective in improving writing quality in content classes. 相似文献
46.
Process Variables, Gelatinized Starch and Moisture Effects on Physical Properties of Mungbean Noodles 总被引:2,自引:0,他引:2
The effects of amounts of gelatinized starch and moisture in the final slurry or dough, cooking time, holding time, and holding temperature on physical properties of mungbean noodles were studied. Cooking loss, cutting stress, work to cut, and transparency of noodles were measured. Moisture content of the final slurry or dough, cooking time, and holding temperature were the most important factors that affected physical properties of mungbean noodles. Processing should be done at moisture contents not exceeding 55%, cooking times not longer than 40 set, and holding temperatures not lower than 3° using 5% of total starch as gelatinized starch and holding time of 36 hr. 相似文献
47.
不良的生活方式和个人行为对健康是一种“自我制造的危害”。吸烟有害世人皆知,然而,近年来吸烟大军更表现为年青化、女性化的特点,青年大学生们吸烟也较普遍,烟草危害在吸烟者身上表现也很明显,已给国家造成极大的疾病负担;青年大学生吸烟还有漫延之势,必须积极开设健康教育,传授保健知识,让他们自己起来同不良的生活习惯作斗争,同时,还必须制定有效的行政干预措施,才能把吸烟带来的毒害控制在最小范围。 相似文献
48.
论述了制造业中、高级岗位职业技术教育的意义、现状、存在问题及其人才市场要求,探讨了办好制造业职业技术教育的几个关键问题。 相似文献
49.
50.
Norbert Delatte 《Canadian Metallurgical Quarterly》2004,130(1):37-43
For the last seven years, a summer Research Experiences for Undergraduates site in structural engineering, funded by the National Science Foundation, has operated at the University of Alabama at Birmingham. During this time, 33 students from 22 colleges and universities have participated in the site. Participants are recruited nationally and have come from as far away as California and Puerto Rico. The program is intended to provide students interested in graduate studies with an introduction to research methods, and to provide students who will not continue their studies past a bachelor of science in civil engineering with a better understanding of how research provides the theoretical foundation of engineering practice. Students work individually with faculty on literature reviews, computer modeling, laboratory testing, and field research. Three students have researched structural failure case studies and the technical and ethical lessons to be learned from them. Participants also have the opportunity to tour construction sites and construction material manufacturers’ and fabricators’ facilities. During the past three years, an ethics seminar series has been added. At the end of the program, students prepare research papers and Web pages documenting their work and present their results to faculty, students, and other participants. 相似文献