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91.
Compared to the online interaction behavior of other users, little is known about the difficulties dyslexic Web users encounter online. This paper reviews existing literature at the intersection of dyslexia and accessibility research to determine what useful knowledge exists regarding this important and relatively large group of users. This review uncovers that, although there are few published usability tests with dyslexic users, there is a considerable body of knowledge on dyslexia as well as many design guidelines for authoring dyslexic-accessible interfaces. Through a comparison of existing accessibility guidelines for dyslexic and non-dyslexic users and discussion of the plain language movement, it is argued that dyslexic-accessible practices may redress difficulties encountered by all Internet users. This conclusion suggests that usability testing yielding a clearer profile of the dyslexic user would further inform the practice of universal design, but also that enough knowledge is already available to allow doing more to increase accessibility for dyslexic Internet users. 相似文献
92.
An analysis of simultaneous variation in protein structures 总被引:5,自引:0,他引:5
Chelvanayagam G; Eggenschwiler A; Knecht L; Gonnet GH; Benner SA 《Protein engineering, design & selection : PEDS》1997,10(4):307-316
The simultaneous substitution of pairs of buried amino acid side chains
during divergent evolution has been examined in a set of protein families
with known crystal structures. A weak signal is found that shows that amino
acid pairs near in space in the folded structure preferentially undergo
substitution in a compensatory way. Three different physicochemical types
of covariation 'signals' were then examined separately, with consideration
given to the evolutionary distance at which different types of compensation
occur. Where the compensatory covariation tends towards retaining the
combined residue volumes, the signal is significant only at very low
evolutionary distances. Where the covariation compensates for changes in
the hydrogen bonding, the signal is strongest at intermediate evolutionary
distances. Covariations that compensate for charge variations appeared with
equal strength at all the evolutionary distances examined. A recipe is
suggested for using the weak covariation signal to assemble the predicted
secondary structural elements, where the evolutionary distance, covariation
type and weighting are considered together with the tertiary structural
context (interior or surface) of the residues being examined.
相似文献
93.
Supercritical Carbon Dioxide (SC CO2) is used as a reaction/processing medium in the fabrication of fiber‐reinforced composite materials. SC CO2 allows resin (reactive monomer), to penetrate inside the fibers themselves, partitioning into the amorphous regions of the fiber. The crystal structure then templates polymerization of matrix within the fiber. This process produces a composite that exhibits ultralong‐range order from the nanoscale reinforcement of crystals to the macroscale fiber reinforcement of matrix. In addition, SC CO2 lowers resin viscosity and aids in wetting out Nylon 6,6 fiber reinforcement in a process similar to reaction injection molding (RIM) or resin transfer molding (RTM). This article will discuss the fabrication technique in detail, including process parameters and the structure of resulting composites and morphology of modified fibers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1600–1607, 2003 相似文献
94.
Mnica Aguilera Valerio Rossini Ana Hickey Donjete Simnica Fiona Grady Valeria D. Felice Amy Moloney Lauren Pawley Aine Fanning Lorraine McCarthy Siobhan M. OMahony John F. Cryan Ken Nally Fergus Shanahan Silvia Melgar 《International journal of molecular sciences》2021,22(15)
Interactions between the intestinal microbiota, immune system and nervous system are essential for homeostasis in the gut. Inflammasomes contribute to innate immunity and brain–gut interactions, but their role in microbiota–neuro–immune interactions is not clear. Therefore, we investigated the effect of the inflammasome on visceral pain and local and systemic neuroimmune responses after antibiotic-induced changes to the microbiota. Wild-type (WT) and caspase-1/11 deficient (Casp1 KO) mice were orally treated for 2 weeks with an antibiotic cocktail (Abx, Bacitracin A and Neomycin), followed by quantification of representative fecal commensals (by qPCR), cecal short chain fatty acids (by HPLC), pathways implicated in the gut–neuro-immune axis (by RT-qPCR, immunofluorescence staining, and flow cytometry) in addition to capsaicin-induced visceral pain responses. Abx-treatment in WT-mice resulted in an increase in colonic macrophages, central neuro-immune interactions, colonic inflammasome and nociceptive receptor gene expression and a reduction in capsaicin-induced visceral pain. In contrast, these responses were attenuated in Abx-treated Casp1 KO mice. Collectively, the data indicate an important role for the inflammasome pathway in functional and inflammatory gastrointestinal conditions where pain and alterations in microbiota composition are prominent. 相似文献
95.
96.
Seung Min Lee Benjamin P. McCarthy Pavel Hrma Jaehun Chun Richard Pokorny Jaroslav Klouzek Albert A. Kruger 《Journal of the American Ceramic Society》2020,103(3):1615-1630
During the final stages of conversion of melter feed (glass batch) to molten glass, the glass-forming melt becomes a continuous liquid phase that encapsulates dissolving solid particles and gas bubbles that produce primary foam at the bottom of the cold cap (the reacting melter feed in an electric glass-melting furnace). The glass-forming melt viscosity plays a dominant role in primary foam formation, stability, and eventual collapse, thus affecting the rate of melting (the glass production rate per cold-cap area). We have traced the glass-forming melt viscosity during the final stages of feed-to-glass conversion as it changes in response to changing temperature and composition (resulting from dissolving solid particles). For this study, we used high-level waste melter feeds—taking advantage of the large amount of data available to us—and a variety of experimental techniques (feed expansion test, evolved gas analysis, thermogravimetric analyzer-differential scanning calorimetry, X-ray diffraction, and viscometer). Starting with a relatively low value at the moment when the melt connects, melt viscosity reached maximum within the primary foam layer and then decreased to its final melter operating temperature value. At the cold-cap bottom—the boundary between the primary foam layer and the thermal boundary layer—where physicochemical reactions of a melter feed influence the driving force of the heat transfer from the melt to the cold cap, the melt viscosity affects the rate of melting predominantly through its effect on the temperature at which primary foam is collapsing. 相似文献
97.
98.
基于多元目标的主成分分析的热岛效应成因研究——以西安市为例 总被引:1,自引:0,他引:1
城市热岛效应作为城市化进程的负效应,其成因具有复杂性和地域性特征.以西安市为例,基于多元目标分析的主成分方法定量计算了不同影响因子对西安市热岛效应的贡献度大小,并以此为基础,最终筛选了城市人口、人均拥有道路面积、人均拥有机动车数、人均绿化面积、建成区面积、降水量及平均风速7个主要因素作为西安市热岛效应的主要成因;最后,从调整城市规划思路、控制工业热源、调控民用热源等三个方面为出发点构建了应对西安市热岛效应的宏观调控体系,其内容由3个一级指标、12个二级指标和5个三级指标构成.对应对和缓解西安市热岛效应具有积极的指导意义,也为其它城市应对热岛效应提供范式参考. 相似文献
99.
E. J. Tozzi D. M. Lavenson M. J. McCarthy R. L. Powell 《American Institute of Chemical Engineers》2012,58(1):59-68
The evolution of the concentration profiles of an adsorbing solute diffusing in a stagnant bed of cellulosic fibers is measured using magnetic resonance imaging. Effective diffusivities are calculated by matching concentration profiles with a numerical model of one‐dimensional Fickian diffusion. The measured values of the effective diffusion coefficients are interpreted using a model that accounts for the porosity, tortuosity, and adsorption equilibrium constant. The effective diffusivities in fiber beds are significantly lower than the bulk diffusivity of the solute and highly dependent on fiber type. The diffusivity is lower for the fiber type that exhibited stronger adsorption properties. The influence of concentration, adsorption, and other fiber characteristics on diffusion rates and rates of reaction is discussed. © 2011 American Institute of Chemical Engineers AIChE J, 2012 相似文献
100.
Davis Aline M.; Grattan David R.; McCarthy Margaret M. 《Canadian Metallurgical Quarterly》2000,114(5):923
During development, exposure to gonadal steroids results in brain sexual differentiation. Postnatally, hypothalamic gamma-aminobutyric acid (GABA) levels are almost double in males versus females. We hypothesized that increased GABA neonatally results in masculinization. Males, females, and androgenized females were infused intrahypothalamically with antisense oligonucleotides against glutamic acid decarboxylase (GAD) mRNA at birth to reduce GABA synthesis. GAD protein and GABA levels were reduced 24 hr later without obvious toxic effects, as determined by histological examination. As adults, neonatally antisense-treated, androgenized females showed reduced intromission-like behavior and lordosis quotients compared with vehicle and scrambled controls. Lordosis quotients were reduced about 50% in nonandrogenized females versus vehicle and scrambled controls. These data suggest that GABA is involved in mediating brain sex differentiation and may act in both males and females. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献