全文获取类型
收费全文 | 939篇 |
免费 | 33篇 |
专业分类
电工技术 | 7篇 |
化学工业 | 222篇 |
金属工艺 | 17篇 |
机械仪表 | 45篇 |
建筑科学 | 59篇 |
矿业工程 | 2篇 |
能源动力 | 9篇 |
轻工业 | 118篇 |
水利工程 | 9篇 |
石油天然气 | 1篇 |
无线电 | 51篇 |
一般工业技术 | 113篇 |
冶金工业 | 217篇 |
原子能技术 | 3篇 |
自动化技术 | 99篇 |
出版年
2023年 | 6篇 |
2022年 | 12篇 |
2021年 | 15篇 |
2020年 | 22篇 |
2019年 | 16篇 |
2018年 | 30篇 |
2017年 | 18篇 |
2016年 | 22篇 |
2015年 | 17篇 |
2014年 | 28篇 |
2013年 | 57篇 |
2012年 | 43篇 |
2011年 | 57篇 |
2010年 | 35篇 |
2009年 | 39篇 |
2008年 | 54篇 |
2007年 | 47篇 |
2006年 | 56篇 |
2005年 | 33篇 |
2004年 | 35篇 |
2003年 | 30篇 |
2002年 | 28篇 |
2001年 | 20篇 |
2000年 | 20篇 |
1999年 | 13篇 |
1998年 | 33篇 |
1997年 | 28篇 |
1996年 | 19篇 |
1995年 | 22篇 |
1994年 | 15篇 |
1993年 | 12篇 |
1992年 | 2篇 |
1991年 | 5篇 |
1990年 | 11篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 8篇 |
1984年 | 11篇 |
1983年 | 5篇 |
1981年 | 7篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1954年 | 1篇 |
排序方式: 共有972条查询结果,搜索用时 15 毫秒
1.
Discusses the cover art for this issue of American Psychologist. Portions of the article are based on an interview with the artist, Melissa Miller, on November 6, 2006. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
We describe simple linear time algorithms for coloring the squares of balanced and unbalanced quadtrees so that no two adjacent squares are given the same color. If squares sharing sides are defined as adjacent, we color balanced quadtrees with three colors, and unbalanced quadtrees with four colors; these results are both tight, as some quadtrees require this many colors. If squares sharing corners are defined as adjacent, we color balanced or unbalanced quadtrees with six colors; for some quadtrees, at least five colors are required. 相似文献
3.
R.M. Scanlan W.A. Barletta D. Dell'Orco A.D. McInturff A. Asner E.W. Collings P.F. Dahl H. Desportes A. Devred R. Garre E. Gregory W. Hassenzahl M. Lamm D. Larbalestier D. Leroy P. McIntyre J. Miller T. Shintomi H. ten Kate S. Wipf 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,380(3):544-554
4.
5.
Frijns J.H.M. Mooij J. ten Kate J.H. 《IEEE transactions on bio-medical engineering》1994,41(6):556-566
Presents an upgraded cable model of mammalian myelinated nerve fibers in an extracellularly applied field. The kinetics of the nodes is based upon voltage clamp data in rat motor fibers at 37°C (J.R. Schwartz and G. Eikhof, 1987), while the resting membrane potential is computed with the Goldman equation. The resulting spike shape, conduction velocity, strength/duration behavior, and absolute and relative refractory period are in good quantitative agreement with published experimental data in mammals at normal body temperature and at 20°C. Results at intermediate temperatures however, suggest that the widely used concept of a constant Q10 for the rate constants is invalid. In addition, the model generates realistic abortive spikes towards the end of the absolute refractory period and it can describe the consequences of repetitive firing. The results stress the advantages of a multiple nonlinear node model even if only time aspects of nerve behavior are under study. It turned out, that the model presented here describes in vivo neural properties relevant for electrical prosthesis design better than previous models in literature 相似文献
6.
Rice Catherine; Koinis Daphne; Sullivan Kate; Tager-Flusberg Helen; Winner Ellen 《Canadian Metallurgical Quarterly》1997,33(1):54
68 3-yr-olds received a standard appearance–reality task along with either a trick task, in which the appearance question was placed in the context of a deceptive game, or a reduced information processing task, in which a dual object (e.g., a sponge-rock) was presented along with an object that matched the dual object's identity (a sponge) and one that matched the dual object's appearance (a rock). Children were more likely to pass either the trick or reduced information processing task and fail the standard than the reverse. Thus, 3-yr-olds can grasp the distinction between appearance and reality (a) when their goal is to trick someone, which may prime them to think about the other's mental state, and (b) when they do not need to hold conflicting object identities in mind at the same time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Describes the use of running therapy in the case of a 32 yr old female incest survivor to delineate specific, predictable, and salient characteristics and issues that may inhere to this type of therapy. The need to address client variables and therapist attributes is discussed. Significant interpersonal issues include changes in the therapeutic bound, competition, and body awareness. Characteristics of running therapy include changes in thinking patterns, the use of symbolism and metaphor, and nonverbal communication. The positive effects of aerobic exercise in the context of psychotherapy may lead to a more profound and beneficial experience of psychotherapy. Further understanding of this form of therapy is useful both to those interested in the relationship between exercise and mental health and those studying varieties of psychotherapeutic experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
M. E. Fitzpatrick M. T. Hutchings J. E. King D. M. Knowles P. J. Withers 《Metallurgical and Materials Transactions A》1995,26(12):3191-3198
The effects of a thermal residual stress field on fatigue crack growth in a silicon carbide particle-reinforced aluminum alloy
have been measured. Stress fields were introduced into plates of material by means of a quench from a solution heat-treatment
temperature. Measurements using neutron diffraction have shown that this introduces an approximately parabolic stress field
into the plates, varying from compressive at the surfaces to tensile in the center. Long fatigue cracks were grown in specimens
cut from as-quenched plates and in specimens which were given a stress-relieving overaging heat treatment prior to testing.
Crack closure levels for these cracks were determined as a function of the position of the crack tip in the residual stress
field, and these are shown to differ between as-quenched and stress-relieved samples. By monitoring the compliance of the
specimens during fatigue cycling, the degree to which the residual stresses close the crack has been evaluated.
formerly Research Student, Department of Materials Science and Metallurgy, University of Cambridge
formerly Lecturer, Department of Materials Science and Metallurgy, University of Cambridge
This article is based on a presentation made in the symposium entitled “Creep and Fatigue in Metal Matrix Composites” at the
1994 TMS/ASM Spring meeting, held February 28–March 3, 1994, in San Francisco, California, under the auspices of the Joint
TMS-SMD/ASM-MSD Composite Materials Committee. 相似文献
9.
Parental power assertion is traditionally studied in the behavioral domain--discipline triggered by the child's immediate misbehavior--but rarely in the cognitive domain--parent-child discussions of the child's past misbehavior. Maternal power assertion was observed in "do" and "don't" discipline contexts from 14 to 45 months and in the context of mother-child discourse about a recent misbehavior at 56 months. Mothers' use of power cohered across the "do," "don't," and discourse contexts, but its implications were domain specific. Power assertion in the "don't" discipline context predicted behavioral outcomes (more moral conduct at 56 and 73 months, less antisocial conduct at 73 months) but not cognitive outcomes (moral cognition at 56 and 73 months). Power assertion in the discourse context predicted less mature moral cognition but not moral or antisocial conduct. Mothers' high Neuroticism predicted more power assertion in all three contexts. Child effects were examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Michael Rabinovich Kate L. Olsavsky Burr Leach Mauricio Cabrera‐Ríos José M. Castro 《应用聚合物科学杂志》2008,109(4):2465-2471
Sheet molding compound (SMC) is a fiber‐reinforced polymeric composite. It is often used in automotive, marine, and industrial applications over other materials because of its high strength to density ratio, resistance to corrosion, and low cost. There is a demand in the SMC industry to be able to characterize SMC processability. This is particularly true for heavy truck body panels, one of the fastest growing applications of SMC. Because of their large size and high strength requirement, the molding forces have a major influence in the molding cycle. Also because of the long flow paths involved, the ability of the paste to carry glass needs to be properly characterized when developing new SMC materials. In this article, we demonstrate the benefits of using spiral flow as a processability tester. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献