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排序方式: 共有628条查询结果,搜索用时 15 毫秒
61.
Abramson Lyn Y.; Garber Judy; Edwards Neil B.; Seligman Martin E. 《Canadian Metallurgical Quarterly》1978,87(1):102
Does the learned helplessness model of depression apply to clinically depressed patients and is it specific to depression? Changes in expectancy following success and failure in skill and chance tasks were assessed for depressed nonschizophrenics (unipolar depressives), depressed schizophrenics, nondepressed schizophrenics, and normal controls (32 Ss, aged 18–50 yrs). Unipolar depressives showed smaller changes in expectancy of future success after failure in the skill task than did the controls and both schizophrenic groups. Depressed schizophrenics did not show smaller expectancy changes than nondepressed schizophrenics. The learned helplessness model has been tested primarily in populations with subclinical depression; the present results provide partial support for learned helplessness as a model of one type of severe clinical depression and suggest that learned helplessness is not a general feature of psychopathology. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Comparison on job knowledge is made between B-52 mechanics receiving field training and those receiving technical school full-time for 2 months. After control for aptitude and maintenance experience by means of matched regression estimates, "there is no significant difference in job knowledge on the part of mechanics exposed to the two training environments. Mechanics at higher levels of aptitude and experience benefit most from field training… lower levels of aptitude and experience benefit most from technical school training." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
64.
Self-help cessation programs for smokeless tobacco users: long-term follow-up of a randomized trial.
Hebert H Severson Judy A Andrews Edward Lichtenstein Brian G Danaher Laura Akers 《Nicotine & tobacco research》2007,9(2):281-289
This paper presents long-term outcomes of the largest clinical trial of smokeless tobacco (SLT) cessation reported to date. SLT users in five northwestern states were recruited to call a toll-free number, and 1,069 users were randomized to one of two self-help conditions: either a manual-only condition or an assisted self-help condition, which included the manual, a targeted video, and two support phone calls. Significant between-group differences were not found for either the 12- or 18-month point-prevalence measure of abstinence from either SLT only or all tobacco products using outcomes based on either the responder or intention-to-treat outcomes. However, using a repeated point-prevalence measure across all three assessment points, we found that significantly more assisted self-help participants reported abstinence, compared with manual-only participants. Compared with manual-only participants, those in the assisted self-help condition were significantly more likely to use recommended cessation techniques. Results demonstrate that low-cost, minimal interventions delivered by mail and phone can help a sizable proportion of individuals quit using SLT. 相似文献
65.
Laura Akers Herbert H Severson Judy A Andrews Edward Lichtenstein 《Nicotine & tobacco research》2007,9(9):907-914
This study assessed the cost-effectiveness of two low-intensity programs for quitting smokeless tobacco, based on results of a randomized trial with 1,069 volunteer participants. Cost data were collected for two levels of intervention: manual only (a self-help manual) and assisted self-help (the manual plus a videotape and two supportive phone calls from tobacco cessation counselors). Incremental cost-effectiveness ratios were calculated for assisted self-help vs. quitting on one's own, using the manual-only quit rate and data from another study as alternative proxies for no intervention. A threshold analysis was conducted to determine the spontaneous quit rate at which the manual-only intervention becomes more cost-effective than assisted self-help. The cost to provide and receive the assisted self-help intervention averaged US $56 per participant vs. $20 for the manual-only intervention (societal perspective, Year 2000 dollars). Estimates for incremental cost per quit for the assisted self-help intervention ranged from $922 to $1,758, depending on the proxy used for no intervention. The manual-only intervention was more cost-effective than assisted self-help if quitting among motivated chewers who do not receive treatment does not exceed 3.4%. Support from a wife or partner added little cost to a quit attempt for male chewers ($3-$4). Providing a manual, video, and brief phone counseling to smokeless tobacco users who want to quit is a reasonable use of health care resources. The self-help quitting guide also may be a cost-effective treatment, but it remains to be demonstrated whether it is more effective than quitting on one's own. 相似文献
66.
Mahler BJ Metre PC Crane JL Watts AW Scoggins M Williams ES 《Environmental science & technology》2012,46(6):3039-3045
Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20-35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments-including stormwater runoff, lake sediment, soil, house dust, and most recently, air-contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them. 相似文献
67.
Judy Schneider Ron Radzilowski 《JOM Journal of the Minerals, Metals and Materials Society》2014,66(10):2123-2129
Designers of transportation vehicles (air, land, or sea) continually seek ways to reduce vehicle weight in response to increasing fuel economy mandates, mission requirements, or other competitive pressures. One way to do this is by the selection of material types and their properties based on functional and structural requirements. While these material changes can help meet performance mandates, their implementation in a production environment relies on retaining economic competitiveness. This article traces the history of the various joining processes relevant to the current challenge in joining the very dissimilar families of steel (Fe) and aluminum (Al) alloys. 相似文献
68.
20 overweight and 20 normal weight female undergraduates underwent habituation, classical conditioning, and extinction of the GSR. Overweight Ss were consistently more responsive to the CS (tone) during all 3 phases of the study and were somewhat more responsive to the UCS (shock). Rates of response attenuation and enhancement, however, were not different during any phase. Results are generally consistent with research which demonstrates that overweight Ss are more externally stimulus bound than normals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Judy A. Townley 《International journal of parallel programming》1980,9(2):93-116
Resolution theory offers a simple, complete method for proving theorems but is generally considered impractical. The theorems we are interested in proving arise in the analysis of programs and usually involve quantification. We have developed a system for proving these theorems using resolution, but have embedded in it a simplifier as the central component. The simplifier is an integrated collection of algorithms for normalizing arithmetic, relational, and logical expressions. The knowledge in the simplifier is encoded in procedures, rather than as axioms or rules. We use the simplifier to prove certain theorems, reduce the clutter in theorems, and reduce the cost of unification, Inherent in the normal form algorithms is the notion of strengthening (e.g., inferringa =b froma b ANDb a). We have incorporated the notion into the unification algorithm as well. The design of the system permits its use along a spectrum from pure resolution to resolution with interpretation of the arithmetic and relational operators. Strengthening is a heuristic that permits the movement along this spectrum. We call the approachi-resolution.i-resolution does not preserve completeness; it does define a means for approaching completeness efficiently and systematically. It thus attempts to provide a pragmatic approach to mechanical theorem proving. 相似文献
70.
Overk CR Peng KW Asghodom RT Kastrati I Lantvit DD Qin Z Frasor J Bolton JL Thatcher GR 《ChemMedChem》2007,2(10):1520-1526
The search for the "ideal" selective estrogen receptor modulator (SERM) as a substitute for hormone replacement therapy (HRT) or use in cancer chemoprevention has focused on optimization of estrogen receptor (ER) ligand binding. Based on the clinical and preclinical benzothiophene SERMs, raloxifene and arzoxifene, a family of SERMs has been developed to modulate activity and oxidative lability. Antiestrogenic potency measured in human endometrial and breast cancer cells, and ER ligand binding data were correlated and seen to provide a guide to SERM design only when viewed in toto. The in vitro studies were extended to the juvenile rat model, in which the desired antiestrogenic profile and putative cardiovascular benefits of SERMs were observed. 相似文献