全文获取类型
收费全文 | 330篇 |
免费 | 9篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 9篇 |
化学工业 | 67篇 |
金属工艺 | 9篇 |
机械仪表 | 4篇 |
建筑科学 | 13篇 |
能源动力 | 6篇 |
轻工业 | 44篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 10篇 |
一般工业技术 | 53篇 |
冶金工业 | 85篇 |
自动化技术 | 38篇 |
出版年
2023年 | 4篇 |
2022年 | 15篇 |
2021年 | 12篇 |
2020年 | 4篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 10篇 |
2016年 | 7篇 |
2015年 | 9篇 |
2014年 | 9篇 |
2013年 | 16篇 |
2012年 | 15篇 |
2011年 | 25篇 |
2010年 | 19篇 |
2009年 | 18篇 |
2008年 | 20篇 |
2007年 | 15篇 |
2006年 | 16篇 |
2005年 | 12篇 |
2004年 | 12篇 |
2003年 | 11篇 |
2002年 | 9篇 |
2001年 | 9篇 |
2000年 | 4篇 |
1999年 | 3篇 |
1998年 | 9篇 |
1997年 | 11篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
排序方式: 共有340条查询结果,搜索用时 15 毫秒
1.
Dichotic listening procedures have been used to assess cerebral lateralization in normal Ss. One particularly useful technique is the use of stimuli that fuse into a single percept. Although this procedure has many advantages over other dichotic listening methods, it is particularly susceptible to stimulus dominance, which acts as noise in a S's response data, thus reducing the power of any statistical test of the ear advantage. It is proposed that the solution to this problem is a log-linear analysis of the response data to yield a λ-type index (λ*) that is a measure of ear dominance independent of stimulus dominance. Details of the analysis are provided, as well as a sample analysis of data collected from 104 right-handed and 30 left-handed Ss. Comparisons are drawn between the log-linear analysis and other methods that have been proposed to control for stimulus dominance in this single-response dichotic fusion procedure. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
The mechanical and microstructural properties of 6061+20% Al2O3p and 7005+10% Al2O3p aluminium based metal matrix composites joined by friction stir welding were analyzed in the present study. The two materials were welded into the form of sheets of 7 mm thickness after T6 treatment and were tested in tension at room temperature. The microstructure of the joints was observed by optical microscopy and the fracture surfaces were analyzed by employing a scanning electron microscope equipped with field emission gun in order to study the micromechanisms involved during the deformation. 相似文献
3.
Naturally produced methane shows different delta 13C-values with respect to its origin, e.g., geological or biological. Methane-production of ruminants is considered to be the dominant source from the animal kingdom. Isotopic values of rumen methane--given in literature--range between -80/1000 and -50/1000 and are related to feed composition and also sampling techniques. Keeping cows, camels and sheep under identical feed conditions and sampling rumen gases via implanted fistuale we compared delta PDB 13C-values of methane and CO2 between the species. Referring to mean values obtained from 4 or 5 samples at different times of 11 animals (n = 47) we calculated delta PDB 13C-medians resulting in small but not significant differences within and significant differences between the species for CO2 and methane. The delta PDB 13C-differences between methane and CO2 were statistically equal within and also between the species. Therefore a linear regression of methane values on CO2 is appropriate and leads to: delta PDB 13C(methane)/1000 = 1.57 * delta PDB 13C(CO2)/1000 - 47/1000 with a correlation coefficient of r = 0.87. 相似文献
4.
Tweet this: A uses and gratifications perspective on how active Twitter use gratifies a need to connect with others 总被引:2,自引:0,他引:2
Gina Masullo Chen 《Computers in human behavior》2011,27(2):755-762
Twitter is an Internet social-network and micro-blogging platform with both mass and interpersonal communication features for sharing 140-character messages, called tweets, with other people, called followers. Hierarchical OLS regression of survey results from 317 Twitter users found that the more months a person is active on Twitter and the more hours per week the person spends on Twitter, the more the person gratifies a need for an informal sense of camaraderie, called connection, with other users. Controlling for demographic variables does not diminish this positive relationship. Additionally, frequency of tweeting and number of @replies, public messages between Twitter users, mediate the relationship between active Twitter use and gratifying a need for connection. Results are discussed in light of uses and gratifications theory. 相似文献
5.
In the area of membrane computing, time-freeness has been defined as the ability for a timed membrane system to produce always
the same result, independently of the execution times associated to the rules. In this paper, we use a similar idea in the
framework of spiking neural P systems, a model inspired by the structure and the functioning of neural cells. In particular,
we introduce stochastic spiking neural P systems where the time of firing for an enabled spiking rule is probabilistically
chosen and we investigate when, and how, these probabilities can influence the ability of the systems to simulate, in a reliable
way, universal machines, such as register machines. 相似文献
6.
Milliken Garrett W.; Ferra Gina; Kraiter Kyle S.; Ross Courtney L. 《Canadian Metallurgical Quarterly》2005,119(4):430
Sixteen sifakas (11 Propithecus verreauxi coquereli, 2 Propithecus verreauxi verreauxi form majori, and 3 Propithecus tattersalli) were videotaped as they fed on leaves in an arboreal context. The hand used to feed and the hand used to maintain postural stability was coded. For each subject, the lateral bias of the hand used to feed was opposite the hand used in postural support. Seven sifakas displayed no bias for feeding or posture-related hand use, 7 sifakas displayed significant feeding-related reach preferences for pulling branches to the mouth (5 left- and 2 right-hand preferences), and 9 sifakas exhibited significant hand preferences for postural support (2 left-, 7 right-hand preferent). Although these data do not strongly support the postural origins theory of behavioral lateralization, the modal preference pattern for sifakas that displayed significant hand preferences for posture and feeding involve a left bias for feeding and a right bias for postural support. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Wall Jacqueline Remondet; Busch Monique; Koch Steven M.; Alexander Gina; Minnich Heike; Jackson-Walker Susan 《Canadian Metallurgical Quarterly》2005,2(1):39
Questions are often raised regarding the effectiveness and value of treatment programs for children and families. Recently, programs have been increasingly held accountable for services offered. In response, the member agencies of IARCCA have developed a comprehensive outcome measurement program. This article describes the project, focusing on the conditions that led to its inception and how the measurement plan was developed. In addition, the article includes information on the selection of personnel, measurement instruments, and methods and on the process of data collection. Summary results are provided, including how these results are utilized to improve services. Finally, the continued expansion and future directions of the Outcome Project are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Silver Steven M.; Rogers Susan; Knipe James; Colelli Gina 《Canadian Metallurgical Quarterly》2005,12(1):29
This article presents the results of a time-limited psychological relief effort using eye movement desensitization and reprocessing (EMDR) following the attacks on the World Trade Center on September 11, 2001. Clients made highly significant positive gains on a range of outcome variables, including validated psychometrics and self-report scales. Analyses of the data suggest 2 broad conclusions: EMDR is a useful treatment intervention both in the immediate aftermath of disaster as well as later; the longer treatment is delayed, the greater the level of disturbance experienced by clients. Also discussed are problems in conducting research during mass disaster response situations. A demonstration of an analog to a wait-list control group is provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Friction Stir Welding of Ceramic Particle Reinforced Aluminium Based Metal Matrix Composites 总被引:1,自引:0,他引:1
P. Cavaliere E. Cerri P. Leo L. Marzoli J. Dos Santos 《Applied Composite Materials》2004,11(6):399-399
The mechanical and microstructural properties of 6061+20% Al2O3p and 7005+10% Al2O3p aluminium based metal matrix composites joined by friction stir welding were analyzed in the present study. The two materials were welded into the form of sheets of 7 mm thickness after T6 treatment and were tested in tension at room temperature. The microstructure of the joints was observed by optical microscopy and the fracture surfaces were analyzed by employing a scanning electron microscope equipped with field emission gun in order to study the micromechanisms involved during the deformation. 相似文献
10.
G. Greco T. Svaldo Lanero S. Torrassa R. Young M. Vassalli A. Cavaliere R. Rolandi E. Pelucchi M. Faimali J. Davenport 《Journal of the Royal Society Interface》2013,10(84)
Marine biofouling causes problems for technologies based on the sea, including ships, power plants and marine sensors. Several antifouling techniques have been applied to marine sensors, but most of these methodologies are environmentally unfriendly or ineffective. Bioinspiration, seeking guidance from natural solutions, is a promising approach to antifouling. Here, the eye of the green crab Carcinus maenas was regarded as a marine sensor model and its surface characterized by means of atomic force microscopy. Engineered surface micro- and nanotopography is a new mechanism found to limit biofouling, promising an effective solution with much reduced environmental impact. Besides giving a new insight into the morphology of C. maenas eye and its characterization, our study indicates that the eye surface probably has antifouling/fouling-release potential. Furthermore, the topographical features of the surface may influence the wettability properties of the structure and its interaction with organic molecules. Results indicate that the eye surface micro- and nanotopography may lead to bioinspired solutions to antifouling protection. 相似文献