全文获取类型
收费全文 | 3561篇 |
免费 | 235篇 |
国内免费 | 5篇 |
专业分类
电工技术 | 19篇 |
综合类 | 9篇 |
化学工业 | 962篇 |
金属工艺 | 40篇 |
机械仪表 | 49篇 |
建筑科学 | 209篇 |
矿业工程 | 3篇 |
能源动力 | 56篇 |
轻工业 | 603篇 |
水利工程 | 37篇 |
石油天然气 | 18篇 |
无线电 | 144篇 |
一般工业技术 | 532篇 |
冶金工业 | 637篇 |
原子能技术 | 9篇 |
自动化技术 | 474篇 |
出版年
2023年 | 27篇 |
2022年 | 86篇 |
2021年 | 134篇 |
2020年 | 58篇 |
2019年 | 88篇 |
2018年 | 97篇 |
2017年 | 90篇 |
2016年 | 116篇 |
2015年 | 90篇 |
2014年 | 154篇 |
2013年 | 224篇 |
2012年 | 186篇 |
2011年 | 273篇 |
2010年 | 179篇 |
2009年 | 157篇 |
2008年 | 189篇 |
2007年 | 158篇 |
2006年 | 168篇 |
2005年 | 106篇 |
2004年 | 121篇 |
2003年 | 100篇 |
2002年 | 84篇 |
2001年 | 57篇 |
2000年 | 58篇 |
1999年 | 51篇 |
1998年 | 51篇 |
1997年 | 48篇 |
1996年 | 54篇 |
1995年 | 43篇 |
1994年 | 38篇 |
1993年 | 35篇 |
1992年 | 40篇 |
1991年 | 40篇 |
1990年 | 51篇 |
1989年 | 33篇 |
1988年 | 37篇 |
1987年 | 30篇 |
1986年 | 22篇 |
1985年 | 22篇 |
1984年 | 31篇 |
1983年 | 12篇 |
1982年 | 24篇 |
1981年 | 7篇 |
1980年 | 15篇 |
1979年 | 24篇 |
1978年 | 13篇 |
1977年 | 11篇 |
1975年 | 13篇 |
1971年 | 6篇 |
1969年 | 6篇 |
排序方式: 共有3801条查询结果,搜索用时 31 毫秒
991.
Reviews the book, Career counseling: A narrative approach by Larry Cochran (2000). This book introduces a narrative approach to career counselling. The author specifically makes the distinction that this is a counselling approach, not a career development theory. A narrative approach invites counsellors to make their career interventions with clients more personal. In contrast to the traditional objective emphasis in career counselling, this is a subjective approach that emphasizes meaning and meaning-making. Cochran characterizes the central task of career counselling as "emplotment" rather than matching. Emplotment involves casting the individual as the main character in a career narrative that is meaningful, productive, and fulfilling. The book is intended for scholars, professionals, and graduate students who already have some familiarity with counselling and career development. It is presumed that the reader has at least some knowledge and skill in counselling. At the end of each chapter, there are exercises that enable the reader to apply the principles and concepts outlined in the chapter. A client situation is described, and several questions are used to guide the reader. Overall, this book is a welcome addition to the career literature. Indeed, the approach need not only be used in counselling involving work or occupational problems. Meaning-making and narrative concepts can be applied to any and all issues in people's lives. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
993.
The boundary lubrication of an aluminium-silicon cylinder liner operating under mild wear conditions has been investigated. The interface was lubricated with synthetic six centistokes poly alpha olefin base oil, which contained either calcium sulphonate or calcium sulphonate and zinc dialkyldithiophosphate. Effective replication of silicon grains within an aluminium-silicon alloy using a silicon crystal substrate affords valuable reproduction of tribofilms. The physical and chemical characteristics of films generated on either substrate were comparable. A marked difference in structure was exhibited between the tribofilms formed from either lubricant. Detailed tribological and tribochemical analysis has been conducted on either substrate. 相似文献
994.
D.C. electrical conductivity measurements on ADP single crystals added with simple organic compounds
Pure and impurity added (with urea and thiourea) ADP single crystals were grown by the free evaporation method. D.C. electrical
conductivity measurements were carried out along both the unique axis and perpendicular directions at various temperatures
ranging from 40–150°C by the conventional two-probe method. Activation energies were also determined. The present study indicates
that the conductivity increases with the increase in impurity concentration and temperature. 相似文献
995.
A methodology is presented for the rational function approximation of a passive network function from sampled values of its real part over the bandwidth of interest. The accuracy and validity of the proposed methodology are demonstrated through its application to the fitting of several broadband, multiport transfer functions. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. 相似文献
996.
Researching pedagogy: a sociocultural agenda 总被引:2,自引:0,他引:2
Anne Edwards 《Pedagogy, Culture & Society》2001,9(2):161-186
Pedagogy is currently receiving attention from producers of education policy in England. It is, however, a version of pedagogy that remains located in a history of schooling as social control, of curricular knowledge as a commodity to be transmitted and of teachers as paraprofessionals. Those who resist recent attempts to shape pedagogy, and attempt to enhance both pedagogy and professionalism in order to prepare learners and teachers for informed participation in the new knowledge economy, are constrained by the impoverished understandings of pedagogy available in the United Kingdom. The author argues that understandings of pedagogy that are grounded in the hermeneutic psychology offered by Vygotskian theory can enhance teachers' professionalism and inform a pedagogy for the new knowledge age, 'Vygotsky is concerned to study how people, through the use of their own social activities, by changing their own conditions of existence can change themselves' (Shotter, 1993, p. 111). 相似文献
997.
Change during a 20-week group therapy program was researched for 40 women who were survivors of childhood sexual abuse. Results indicated that the women who participated in group therapy, compared with a quasi-experimental control group, decreased significantly on measures of depression, social maladjustment, self-blame, and posttraumatic stress responses, with no significant increases in anger. Scores on the main variables remained stable during assessment and follow-up periods for the women who participated in group therapy. In addition, there were no significantly different patterns of change based on either sexual abuse variables (number of perpetrators, sexual abuse by a father figure, nature of sexual abuse, and duration) or participation in concurrent individual therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
999.
1000.
Daniel Rodrigues Cardoso Anne M. Frederiksen Alexandre Ataíde da Silva Douglas W. Franco Leif H. Skibsted 《European Food Research and Technology》2008,227(4):1109-1116
Sugarcane spirit extracts of six different Brazilian woods for potential use in manufacturing aging casks were compared with
similar extracts of five oak samples from different geographic origin and heat treatment regarding: (1) content of phenolics
and copper; (2) radical reducing capacity and reactivity toward 2,2-diphenyl-1-picrylhydrazyl radical (DPPH·); and (3) effect
on the rate of oxygen depletion rate in a peroxidating lipid model system. Total phenolic contents of the Brazilian wood extracts
ranged from 0.65 (canela-sassafrás) to 6.4 (jatobá) mmolGAE L−1 and from 1.39 to 2.87 mmolGAE L−1 for oak extracts. Flavonoids ranged from 1.54 × 10−4 (ipê) to 6.5 × 10−2 (oak) mmolrutin L−1, and tannins from below the detection limit to 0.22 (jatobá) mmoltannic acid L−1. Correlation was observed for the antioxidant capacity versus phenolics/flavonoids/tannins content, where oak extracts exhibit
the highest radical scavenging capacity compared to Brazilian woods. Rate constant for radical scavenging by the extracts
ranged from 4.9 × 103 M−1 s−1 (canela-sassafrás) to 9.7 × 104 M−1 s−1 (oak). The oxygen consumption index showed the Brazilian woods amendoim and jatobá to be more efficient inhibitors than the
oak extracts for lipid autoxidation initiated by metmyoglobin, despite that the oak extracts seem to be more efficient to
scavenge DPPH·. No simple correlation with phenolics or copper content could be established, and a prooxidative tendency was
observed for the extracts of canela-sassafrás, castanheira, and louro-canela. 相似文献