全文获取类型
收费全文 | 678篇 |
免费 | 55篇 |
专业分类
电工技术 | 7篇 |
化学工业 | 99篇 |
金属工艺 | 8篇 |
机械仪表 | 9篇 |
建筑科学 | 16篇 |
能源动力 | 47篇 |
轻工业 | 44篇 |
水利工程 | 10篇 |
石油天然气 | 3篇 |
无线电 | 73篇 |
一般工业技术 | 130篇 |
冶金工业 | 179篇 |
原子能技术 | 2篇 |
自动化技术 | 106篇 |
出版年
2023年 | 5篇 |
2022年 | 5篇 |
2021年 | 22篇 |
2020年 | 18篇 |
2019年 | 12篇 |
2018年 | 31篇 |
2017年 | 17篇 |
2016年 | 24篇 |
2015年 | 12篇 |
2014年 | 18篇 |
2013年 | 35篇 |
2012年 | 38篇 |
2011年 | 43篇 |
2010年 | 21篇 |
2009年 | 34篇 |
2008年 | 39篇 |
2007年 | 39篇 |
2006年 | 24篇 |
2005年 | 22篇 |
2004年 | 29篇 |
2003年 | 19篇 |
2002年 | 15篇 |
2001年 | 13篇 |
2000年 | 12篇 |
1999年 | 7篇 |
1998年 | 28篇 |
1997年 | 14篇 |
1996年 | 11篇 |
1995年 | 15篇 |
1994年 | 11篇 |
1993年 | 16篇 |
1992年 | 8篇 |
1990年 | 2篇 |
1989年 | 7篇 |
1988年 | 2篇 |
1987年 | 6篇 |
1986年 | 2篇 |
1985年 | 6篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 5篇 |
1973年 | 5篇 |
1971年 | 2篇 |
1955年 | 1篇 |
排序方式: 共有733条查询结果,搜索用时 15 毫秒
1.
Daniela Frasca Maria Romero Alain Diaz Denisse Garcia Seth Thaller Bonnie B. Blomberg 《International journal of molecular sciences》2021,22(4)
Senescent cells accumulate in the adipose tissue (AT) of individuals with obesity and secrete multiple factors that constitute the senescence-associated secretory phenotype (SASP). This paper aimed at the identification of B cells with a SASP phenotype in the AT, as compared to the peripheral blood, of individuals with obesity. Our results show increased expression of SASP markers in AT versus blood B cells, a phenotype associated with a hyper-metabolic profile necessary to support the increased immune activation of AT-derived B cells as compared to blood-derived B cells. This hyper-metabolic profile is needed for the secretion of the pro-inflammatory mediators (cytokines, chemokines, micro-RNAs) that fuel local and systemic inflammation. 相似文献
2.
Takeshi Kondo Sang Min Lee Michal Malicki Benoit Domercq Seth R. Marder Bernard Kippelen 《Advanced functional materials》2008,18(7):1112-1118
We report on a single‐layer organic memory device made of poly(N‐vinylcarbazole) embedded between an Al electrode and ITO modified with Ag nanodots (Ag‐NDs). Devices exhibit high ON/OFF switching ratios of 104. This level of performance could be achieved by modifying the ITO electrodes with some Ag‐NDs that act as trapping sites, reducing the current in the OFF state. Temperature dependence of the electrical characteristics suggest that the current of the low‐resistance state can be attributed to Schottky charge tunnelling through low‐resistance pathways of Al particles in the polymer layer and that the high‐resistance state can be controlled by charge trapping by the Al particles and Ag‐NDs. 相似文献
3.
Seth Green George Turkiyyah 《International journal for numerical methods in engineering》2004,61(3):380-405
We present a new method for enforcing boundary conditions within subdivision finite element simulations of thin shells. The proposed framework is demonstrated to be second-order accurate with respect to increasing refinement in the displacement and energy norm for simply supported, clamped, free and symmetric boundary conditions. Second-order accuracy on the boundary is consistent with the accuracy of subdivision-based approaches for the interior of a body. Our proposed framework is applicable to both triangular and quadrilateral refinement schemes, and does not impose any topological requirements upon the underlying subdivision control mesh. Several examples from an obstacle course of benchmark problems are used to demonstrate the convergence of the scheme. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
4.
Kelly Jeffrey A.; Murphy Debra A.; Sikkema Kathleen J.; Kalichman Seth C. 《Canadian Metallurgical Quarterly》1993,48(10):1023
Behavior change remains the only means for primary prevention of HIV disease. Psychology should take a leading role in efforts to curtail the epidemic, but has not contributed to HIV prevention at a level proportionate to the urgency of the crisis. The authors propose an updated agenda for behavioral research on AIDS-HIV prevention implementing accelerated community trials of promising behavior change models, conducting trials of community-level interventions on a large scale and focused on populations most vulnerable to HIV infections, establishing partnerships between HIV research and community service organizations, integrating efforts from across psychology disciplines to advance and refine HIV prevention interventions, and mobilizing interdisciplinary HIV prevention resources and communication mechanisms to rapidly translate research findings to community and public policy arenas. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
A system for recognizing a large class of engineering drawings 总被引:9,自引:0,他引:9
Yuhong Yu Samal A. Seth S.C. 《IEEE transactions on pattern analysis and machine intelligence》1997,19(8):868-890
We present a system for recognizing a large class of engineering drawings characterized by alternating instances of symbols and connection lines. The class includes domains such as flowcharts, logic and electrical circuits, and chemical plant diagrams. The output of the system, a netlist identifying the symbol types and interconnections, may be used for design simulation or as a compact portable representation of the drawing. The automatic recognition task is divided into two stages: 1) domain-independent rules are used to segment symbols from connection lines in the drawing image that has been thinned, vectorized, and preprocessed in routine ways; 2) a drawing understanding subsystem works in concert with a set of domain-specific matchers to classify symbols and correct errors automatically. A graphical user interface is provided to correct residual errors interactively and to log data for reporting errors objectively. The system has been tested on a database of 64 printed images drawn from text books and handbooks in different domains and scanned at 150 and 300 dpi resolution 相似文献
6.
Sherman Seth J.; Atri Alireza; Hasselmo Michael E.; Stern Chantal E.; Howard Marc W. 《Canadian Metallurgical Quarterly》2003,117(3):526
Eight subjects studied a set of complex visual images after administration of 0.4 mg scopolamine. Another 8 subjects performed the same task without drug administration. On a subsequent item recognition test, subjects rated, on a 5-point scale, their confidence that the studied pictures and an equal number of unstudied lures were actually presented. Results showed that scopolamine affected responses to studied items, but not unstudied lures, demonstrating an unambiguous effect of scopolamine on recognition memory. To describe the scopolamine-injected subjects' data, the authors constructed a new model of 2-process recognition that includes the A. P. Yonelinas (1994) model as a limiting case. The model analysis suggests that scopolamine affected both familiarity and recollection. In particular, scopolamine did not affect the frequency with which recollection took place, but rather, affected the amount of recollected information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Kalichman Seth C.; Russell Robert L.; Hunter Tricia L.; Sarwer David B. 《Canadian Metallurgical Quarterly》1993,61(5):887
The effects of celebrity self-disclosure of HIV seropositivity on perceptions of HIV and AIDS were investigated. AIDS-related interest and knowledge measures were collected from 468 men before and after basketball star Earvin "Magic" Johnson's self-disclosure of HIV seropositivity. Increased interest in AIDS paralleled media coverage of the announcement, with the most substantial effects occurring within 2 wks. Perceived impact of the disclosure was greatest among African-American men and men who had not previously known someone with HIV/AIDS. Celebrity self-disclosure appears to affect perceptions through mechanisms similar to those involved in personally knowing someone infected with HIV. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
9.
Nestor Paul G.; Faux Steven F.; McCarley Robert W.; Penhune Virginia; Shenton Martha E.; Pollak Seth; Sands Stephen F. 《Canadian Metallurgical Quarterly》1992,101(4):682
M. I. Possner's 1980 reaction time (RT) paradigm was used to examine the engagement and disengagement operations of visual selective attention in patients with schizophrenia. In the 1st experiment 14 medicated, chronic schizophrenic Ss (diagnosed by criteria of the Diagnostic and Statistical Manual of Mental Disorders [DSM-I]), and 15 age-matched normal and control Ss made a speeded response to a target preceded by a valid, and invalid, or no cue. Control Ss showed the expected advantage and disadvantage in RT for valid and invalid cues, which suggests intact engagement and disengagement operations. For schizophrenic Ss, valid cues also enhanced RT, but invalid cues did not slow RT. Similar results were found in the 2nd experiment. The failure of unpredictable, invalid cues to inhibit RT in chronic schizophrenia may be related to an abnormality in the disengagement operation of selective attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Coatings derived from organofunctional silanes have been investigated as possible replacements for the chromate-based systems used in the aerospace industry. In this study, organofunctional silanes [bis-(triethoxysilylpropyl)ethane and bis(triethoxysilylpropyl) tetrasulfide] were reacted with commercially available acrylate (ECO-CRYL™ 9790) and epoxy (EPI-REZ™ WD-510) resins, resulting in a one-step, low-VOC, chromate-free primer. Liquid-state 29Si and 13C NMR were used to determine structural characteristics of various optimized formulations. 相似文献