全文获取类型
收费全文 | 795篇 |
免费 | 41篇 |
专业分类
电工技术 | 8篇 |
化学工业 | 153篇 |
金属工艺 | 12篇 |
机械仪表 | 15篇 |
建筑科学 | 17篇 |
矿业工程 | 2篇 |
能源动力 | 15篇 |
轻工业 | 96篇 |
水利工程 | 12篇 |
石油天然气 | 3篇 |
无线电 | 61篇 |
一般工业技术 | 143篇 |
冶金工业 | 222篇 |
原子能技术 | 9篇 |
自动化技术 | 68篇 |
出版年
2023年 | 10篇 |
2022年 | 17篇 |
2021年 | 32篇 |
2020年 | 22篇 |
2019年 | 25篇 |
2018年 | 24篇 |
2017年 | 30篇 |
2016年 | 26篇 |
2015年 | 15篇 |
2014年 | 17篇 |
2013年 | 37篇 |
2012年 | 31篇 |
2011年 | 50篇 |
2010年 | 37篇 |
2009年 | 31篇 |
2008年 | 27篇 |
2007年 | 28篇 |
2006年 | 21篇 |
2005年 | 17篇 |
2004年 | 14篇 |
2003年 | 16篇 |
2002年 | 10篇 |
2001年 | 12篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1998年 | 45篇 |
1997年 | 26篇 |
1996年 | 16篇 |
1995年 | 22篇 |
1994年 | 19篇 |
1993年 | 9篇 |
1992年 | 7篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 3篇 |
1987年 | 4篇 |
1986年 | 3篇 |
1985年 | 10篇 |
1984年 | 7篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 11篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 14篇 |
1976年 | 10篇 |
1973年 | 5篇 |
1972年 | 3篇 |
1971年 | 3篇 |
排序方式: 共有836条查询结果,搜索用时 15 毫秒
101.
Discusses articles by D. E. Polkinghorne (see record 1985-07630-001), G. S. Howard (see record 1985-07626-001), and M. J. Patton (see record 1985-07629-001), who recommended that counseling research be reoriented. The accepted definition of science, based primarily on the work of pre-20th-century physical scientists, does not fit in with the current advanced thinking about the philosophy of science. Similarities and differences in the 3 articles are considered, and problems that arise from the inadequacy of available psychometric and statistical techniques for the new kinds of research envisaged are discussed. It is concluded that the rethinking of some assumptions with regard to determinism and the way counseling is defined are necessary. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
The development of the competent self in adolescence, the interrelationship of psychotherapeutic and psychoeducational change, and the role of the high school counselor as a mental health gatekeeper were explored in a pre–post experimental–control design study of group counseling. 147 exemplary ("getting their lives together well and handling school well") and marginal ("having trouble getting their lives together and managing school") high school students participated. Precounseling assessments and patterns of change over the counseling period supported the 1st author's hierarchical competence configuration model of psychosocial functioning, consisting of self-attitudes, world-attitudes, and relevant behavioral attributes. Overall effectiveness of counseling was indicated at multiple levels by significant goal attainment (Kiresuk-Sherman Goal Attainment Scale) and by increased self-efficacy (Rotter's Internal–External Locus of Control Scale). The impact of counseling was significantly different for exemplary than for marginal students and for students from different race and sex subgroups. These findings confirm the interrelation of change patterns at behavioral and personality levels, the importance of sociocultural factors in individual psychosocial change patterns, and the potential therapeutic impact of relatively brief psychoeducational-psychotherapeutic interventions. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Plasmas or ionized gases, existing at temperatures as high as 50,000°C, constitute the highest controlled temperatures known. At these temperatures, reactions occur about which we have little or no knowledge. This paper explores. the various possibilities of using plasma devices for extractive metallurgy. 相似文献
104.
When funds are tight, design and development are curtailed first; however, marketing is one of the last areas to go. That's the view of two recent electrical engineering graduates who spent last summer in a ten-week pilot program for junior marketing engineers. The marketing assistantship program described here was developed by the Hewlett-Packard Co. to acquaint engineering undergraduates with the job opportunities available in marketing. The authors soon realized that their initial impressions of this field were somewhat misleading. 相似文献
105.
The performances of 1 g h?1 and 20 kg h?1 flash pyrolysers are compared for three Australian coals: Loy Yang brown coal (Victoria), Liddell bituminous coal (New South Wales), and Millmerran sub-bituminous coal (Queensland). The two reactors gave comparable yields of tar, char and C1–C3 hydrocarbon gases over a range of operating conditions for each particular coal. The yield of total volatile matter from Millmerran coal was similar from both reactors, as were the compositions of chars from Loy Yang coal and tars from the Liddell and Millmerran coals. For Millmerran coal, the yields of tar, C1–C3 gases and volatiles from the large reactor below 650 °C, were slightly lower than for the small reactor, possibly owing to a shorter retention time of Millmerran coal particles in the large-scale reactor. At a temperature near 600 °C tar yields were independent of tar concentration in the effluent gas, over a range 0.0025–0.1 kg m?3 for Liddell coal, 0.005–0.26 kg m?3 for Millmerran coal and 0.0045–0.09 kg m?3 for Loy Yang coal. The tar yields from Millmerran and Liddell coals at 600 °C in the large reactor, correlate directly with the atomic ratio of the parent coal, in the same manner as that found for a wider range of bituminous coals in the small-scale reactor. 相似文献
106.
Using a national sample of hospital discharges, we found identical seasonal patterns for spontaneous abortions and conceptions but no significant seasonal variation in the rate of spontaneous abortions per 1,000 conceptions. The differences between our findings and those of previous investigators of spontaneous abortion may reflect our more comprehensive definition of spontaneous abortion, our more complete estimate of the monthly number of conceptions, and our more rigorous statistical analysis. The periodic regression analysis (PRA) reported in our study may be useful in other studies that monitor short-term trends. 相似文献
107.
The Cartter Report and Roose-Andersen Reports (sponsored by the American Council of Education) on quality of graduate education in American universities have been used as a basis for national policy and funding judgments, and for institutional, academic discipline, and student applicant uses. It is argued that instead of serving the public purposes for which they were intended, these reports serve more directly private guild interests of the participating disciplines, particularly psychology. Reasons include the fact that psychology has become increasingly technician-oriented, and the sampling procedure used to select raters and the questions asked were biased. These issues could be better approached by defining appropriate models of excellent graduate programs, developing scales for rating the variables considered to contribute to excellence, and then assessing the validity of those measures. The consequences of present biased rating procedures are far too significant for society and students for psychologists to continue to ignore. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
A workable psychology of individuality is "one that would generate good research ideas, which, in turn, would lead to steady increases in dependable knowledge." Individual uniqueness "is described primarily in terms of choice and organization, and I consider it the task of psychologists to make those concepts workable—to bring them into the general stream of thinking in research, assessment, and practical activities." Tyler stresses "the significance of concepts of choice and organization in an inclusive psychology of the development of the human individual… . At each stage of our lives, we impose limits on the next stage, by the choices we make and the ways in which we organize what we have experienced." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
110.
M. G. O'Reilly P. O. Olomolaiye A. H. Tyler T. Orr 《Building Research & Information》1994,22(5):247-251
A useful review of issues of health and safety linked to legislation, as well as highlighting the most serious types of accidents identified in the survey. 相似文献