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971.
Schmidt Norman B.; Storey Julie; Greenberg Benjamin D.; Santiago Helen T.; Li Qian; Murphy Dennis L. 《Canadian Metallurgical Quarterly》2000,109(2):308
The present study evaluated the singular and interactive effects of a functional polymorphism (variation) in the serotonin transporter (5-HTT) gene and a psychological trait (anxiety sensitivity [AS], i.e., fear of arousal symptoms) in predicting subjective and physiological responses to a 35% carbon dioxide (CO?) challenge in a community sample (N?=?72). Genotypes were divided into 2 groups in accord with prior research. Findings were partially supportive of the hypothesized risk model. These indicated that the Group L genotype (homozygous for the 1 allele), compared with the Group S genotype (homozygous for the s allele plus heterozygous individuals), predicted greater fearful response to the biological challenge. There was also an AS?×?Genotype interaction predicting heart rate variability (HRV) in response to the CO?, suggesting that high AS plus Group L status predicts decreased HRV. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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973.
Benjamin J. Stewart Ali Navid Kristen S. Kulp Jennifer L. S. Knaack Graham Bench 《Yeast (Chichester, England)》2013,30(2):81-91
Methylglyoxal, a reactive, toxic dicarbonyl, is generated by the spontaneous degradation of glycolytic intermediates. Methylglyoxal can form covalent adducts with cellular macromolecules, potentially disrupting cellular function. We performed experiments using the model organism Saccharomyces cerevisiae, grown in media containing low, moderate and high glucose concentrations, to determine the relationship between glucose consumption and methylglyoxal metabolism. Normal growth experiments and glutathione depletion experiments showed that metabolism of methylglyoxal by log‐phase yeast cultured aerobically occurred primarily through the glyoxalase pathway. Growth in high‐glucose media resulted in increased generation of the methylglyoxal metabolite d ‐lactate and overall lower efficiency of glucose utilization as measured by growth rates. Cells grown in high‐glucose media maintained higher glucose uptake flux than cells grown in moderate‐glucose or low‐glucose media. Computational modelling showed that increased glucose consumption may impair catabolism of triose phosphates as a result of an altered NAD+:NADH ratio. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
974.
975.
Recently, Vul and Pashler (2008) demonstrated that the average of 2 responses from a single subject to general knowledge questions was more accurate than either single estimate. Importantly, this reveals that each guess contributes unique evidence relevant to the decision, contrary to views that eschew probabilistic representations of the evidence-gathering and decision-making processes. We tested an implication of that view by evaluating this effect separately in individuals with a range of memory spans. If memory span is the buffer in which retrieved information is assembled into an evaluation, then multiple estimates in individuals with lower memory spans should exhibit greater independence from one another than in individuals with higher spans. Our results supported this theory by showing that averaging 2 guesses from lower span individuals is more beneficial than averaging 2 guesses from higher span individuals. These results demonstrate a rare circumstance in which lower memory span confers a relative advantage on a cognitive task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
976.
Winegard Benjamin; Bailey Drew H.; Oxford Jonathan; Geary David C. 《Canadian Metallurgical Quarterly》2010,65(9):928
Comments on Evolutionary psychology: Controversies, questions, prospects, and limitations (see record 2010-02208-001) by Confer et al. We applaud Confer et al.’s (February–March 2010) clarifications of the many misconceptions surrounding the use of evolutionary analyses in psychology. As they noted, such misunderstandings are common and result in a curious tendency of some of our colleagues to criticize evolutionary psychology without a firm understanding of evolution itself. Confer et al. also did an admirable job acknowledging current unresolved issues among evolutionary psychologists (e.g., the relative importance of group selection on humans). The above said, we disagree with their view that a current limitation of evolutionary psychology is its inability to explain phenomena “that appear to reduce an individual’s reproductive success, and cannot be explained by mismatches with, or hijacking of, our psychological mechanisms by modern-day novel inputs” (Confer et al., 2010, p. 122). Mismatches between modern environments and environments of evolutionary adaptedness are only one set of explanations for seemingly maladaptive traits (Nesse, 2005). Another set involves evolutionary trade-offs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
977.
Benjamin Ibarra-Sevilla 《Nexus Network Journal》2013,15(1):107-125
Benjamin Ibarra-Sevilla examines the role of the sphere in the Open Chapel built in San Pedro y San Pablo Teposcolula during sixteenth century. This unique Mexican building contains a complex ribbed vault designed on a hexagonal plan forming a semi-spherical dome. The investigation examines the use of the sphere in this structure in light of the design precepts practiced during the Renaissance in Europe. Furthermore, the study finds the connections of these precepts with a mathematical solution to the sphere based on convex shapes theories. By revealing the intricacies of the underlying geometry applied to design this building, this text aims to demonstrate the scholastic and architectural relevance of this refined Mexican piece of architecture. 相似文献
978.
This paper is a modest contribution to the vast exploration to be embarked upon as our maps appear increasingly outdated. We will first explore some outmoded ‘taken for granted’ assumptions and visions: this section aims to clarify why the crisis management world has profoundly changed and how the current understanding of crises and theoretical frameworks is becoming increasingly less adequate. Then, we will try to meet the second challenge of this special issue, by suggesting innovative approaches that will contribute to elaborate the building blocks of a theory of crisis management. We will propose a new theoretical framework, through the use of a fractal approach, following the footsteps of Benoit Mandelbrot, in order to rethink and capture the essence of the new theatre of operations that must be dealt with. Throughout, we will show how this original framework could be put into practice and what its limitations and perspectives are. 相似文献
979.
The achievement of optimum adhesion between a thermoset and an inorganic material is an important goal for the composites and coatings industries. There is a growing interest in the use of structural surface modifiers, such as nanotubes, nanoparticles, and whiskers, to improve this adhesion. Here, a method for electrostatically depositing poly(ethylene imine)‐functionalized silica nanoparticles onto E‐glass fibers was developed. The deposition of 26‐nm functionalized particles onto glycidyloxypropyltrimethoxysilane (GPS)‐functionalized E‐glass fibers and then their embedding in a resin of diglycidyl ether of bisphenol A and m‐phenylene diamine increased the interfacial shear strength (IFSS) 35% over that of bare fibers and 8% over that of GPS‐functionalized fibers. IFSS was highly dependent on the particle size; the 16‐nm functionalized particles had little effect on the IFSS. When the particles size was increased to 71 and 100 nm, this led to increasingly poor IFSS values, whereas the 26‐nm particles produced the best results. Similar results were seen with the transverse flexural strength of the unidirectional composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41516. 相似文献
980.
Scale‐up of agitated drying: Effect of shear stress and hydrostatic pressure on active pharmaceutical ingredient powder properties 下载免费PDF全文
Brenda Remy Weston Kightlinger Eric M. Saurer Nathan Domagalski Benjamin J. Glasser 《American Institute of Chemical Engineers》2015,61(2):407-418
Scale‐up of agitated drying processes to minimize particle size changes in active pharmaceutical ingredients (API) can be challenging. Particle agglomeration or attrition problems due to agitated drying are often discovered on the initial scale‐up from the lab to the plant. Traditional laboratory drying equipment has not successfully reproduced the degree of agglomeration or attrition observed at scale. This discrepancy may be attributed to the ability of particulate solids, such as crystalline API's to transfer stresses from the normal direction into the shearing direction. As batch size increases during scale‐up, the compressive and shearing forces experienced by the API increase. To overcome this limitation, a modified laboratory setup was constructed which reproduces the range of hydrostatic pressures observed during scale‐up. This work highlights the use of the modified setup to characterize the propensity for particle attrition to occur at different stages of the drying process by measuring impeller torque. Torque measurements of the API powder at different hydrostatic pressures revealed a behavior consistent with Coulomb's law of friction. The torque data obtained from these measurements were used to determine the bulk friction coefficient for API powder beds at different liquid content. Additionally, the amount of work done by the impeller blades was correlated to the degree of particle attrition observed. A workflow for assessing risk of API attrition at scale is described. © 2014 American Institute of Chemical Engineers AIChE J, 61: 407–418, 2015 相似文献