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991.
Howard Marc W.; Jing Bing; Rao Vinayak A.; Provyn Jennifer P.; Datey Aditya V. 《Canadian Metallurgical Quarterly》2009,35(2):391
In episodic memory tasks, associations are formed between items presented close together in time. The temporal context model (TCM) hypothesizes that this contiguity effect is a consequence of shared temporal context rather than temporal proximity per se. Using double-function lists of paired associates (e.g., A–B, B–C) presented in a random order, the authors examined associations between items that were not presented close together in time but that were presented in similar temporal contexts. After learning, across-pair associations fell off with distance in the list, as if subjects had integrated the pairs into a coherent memory structure. Within-pair associations (e.g., A–B) were strongly asymmetric favoring forward transitions; across-pair associations (e.g., A–C) showed no evidence of asymmetry. While this pattern of results presented a stern challenge for a heteroassociative mediated chaining model, TCM provided an excellent fit to the data. These findings suggest that contiguity effects in episodic memory do not reflect direct associations between items but rather a process of binding, encoding, and retrieval of a gradually changing representation of temporal context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Sin Hock-Peng; Nahrgang Jennifer D.; Morgeson Frederick P. 《Canadian Metallurgical Quarterly》2009,94(4):1048
Although it is an explicitly dyadic approach to leadership, some leader–member exchange (LMX) research has been characterized by relatively low levels of agreement between leader and member judgments of the relationship. Using a combination of meta-analytic methods and primary data collection, the authors sought to explore several theoretically and methodologically meaningful factors that might account for lower levels of agreement. On the basis of data from 64 independent samples (N = 10,884 dyads), the authors found that overall agreement was moderate in nature (ρ = .37). In addition, they found that longer relationship tenure, affectively oriented relationship dimensions, and ad hoc sampling techniques showed the highest levels of agreement. Empirical results from 98 matched dyads revealed that the extent of LMX agreement increases as the length of relationship tenure and intensity of dyadic interaction increases. Implications for LMX theory and future empirical research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Stephens Mary Ann Parris; Fekete Erin M.; Franks Melissa M.; Rook Karen S.; Druley Jennifer Ann; Greene Kenneth 《Canadian Metallurgical Quarterly》2009,28(1):48
Objective: The authors investigated health-related effects of social control (influence) that spouses exert in relation to osteoarthritis patients' medical adherence after total knee replacement surgery. Patients' behavioral and emotional responses to control were examined as mediators of associations between spouses' use of two control strategies (pressure, persuasion) and patients' physical and psychological recovery. Design: The authors used a three-wave panel design with assessments at one month before surgery, 1 month and 3 months after surgery. Data were collected during in-person interviews with 70 married, older adult patients. Main Outcome Measures: Recovery outcomes were assessed as improvement in knee limitations and depressive symptoms at the 3 month follow-up. Results: Spousal pressure and persuasion at one month postsurgery were indirectly associated with patients' recovery outcomes through patients' positive emotional responses to control. Conclusion: Although there are often immediate behavioral benefits in response to partners' use of both pressure and persuasion, the long-term health effects of these strategies seem to be accounted for by their opposing links to positive emotions. Findings further refine theory on health-related social control in marriage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Ganiban Jody M.; Ulbricht Jennifer A.; Spotts Erica L.; Lichtenstein Paul; Reiss David; Hansson Kjell; Neiderhiser Jenae M. 《Canadian Metallurgical Quarterly》2009,23(5):646
Analyses assessed the degrees to which personality accounts for associations between marital quality and parenting and mediates genetic contributions to these relationships. Participants included 318 male and 544 female same-sex twin pairs from the Twin and Offspring Study in Sweden. All twins completed self-report measures of marital quality and personality (anxiousness, aggression, sociability). Composite measures of parent negativity and warmth were derived from the twins’ and their adolescent children’s ratings of the twins’ disciplinary styles and the emotional tone of the parent–child relationship. Observational ratings of marital quality and parenting were also obtained for a subset of twins. Personality characteristics explained 33% to 42% of the covariance between reported marital quality and parenting and 26% to 28% of the covariance between observed marital quality and parenting. For both sets of analyses, personality accounted for more than half of the genetic contributions to covariance between marital quality and parenting. Results indicate that personality significantly contributes to associations between marital quality and parenting and that personality is an important path through which genetic factors contribute to family relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Jennifer Bergers Stefan Herion Susanne Hhler Christian Müller Jrg Sttzel 《Stahlbau》2006,75(11):897-915
Analysis of fatigue details typically used in crane structures. For joints and attachments in crane structures usually the verification of the fatigue strength governs the design. When using the nominal stress approach some details often used in crane structures, especially welded details, cannot be classified according to the tables of fatigue classes given in the standards. Together with representatives from the crane industry such details have been identified. In the frame of the FOSTA research project P 512 fatigue tests have been carried out, so that proposals for the classification according to Eurocode 3 could be made. In addition, fatigue tests on structural details already covered by the codes have been executed to check the influence of material strength. A general increase of the fatigue strength when using high strength steel could not be observed but details with low notch effects show a better behaviour compared with normal strength steel. This is attributed to higher fabrication qualities. The research project P 512 was funded by the Stiftung Stahlanwendungsforschung, Essen, and has been carried out in behalf of the Forschungsvereinigung Stahlanwendung e.V. 相似文献
996.
Mercury emissions to the atmosphere from anthropogenic sources in Europe in 2000 and their scenarios until 2020 总被引:1,自引:0,他引:1
Pacyna EG Pacyna JM Fudala J Strzelecka-Jastrzab E Hlawiczka S Panasiuk D 《The Science of the total environment》2006,370(1):147-156
The paper reviews the current state of knowledge regarding European emissions of mercury and presents estimates of European emissions of mercury to the atmosphere from anthropogenic sources for the year 2000. This information was then used as a basis for Hg emission scenario development until the year 2020. Combustion of coal in power plants and residential heat furnaces generates about half of the European emissions being 239 tonnes. The coal combustion is followed by the production of caustic soda with the use of the Hg cell process (17%). Major points of mercury emission generation in the mercury cell process include: by-product hydrogen stream, end box ventilation air, and cell room ventilation air. This technology is now being changed to other caustic soda production technologies and further reduction of Hg emissions is expected in this connection. The third category on the list of the largest Hg emitters in Europe is cement production (about 13%). The largest emissions were estimated for Russia (the European part of the country), contributing with about 27% to the European emissions, followed by Poland, Germany, Spain, Ukraine, France, Italy and the United Kingdom. Most of these countries use coal as a major source of energy in order to meet the electricity and heat demands. In general, countries in the Central and Eastern Europe generated the main part of the European emissions in 2000. Emission reductions between 20% and 80% of the 2000 emission amounts can be obtained by the year 2020, as estimated by various scenarios. 相似文献
997.
Arunsri Leejeerajumnean S Craig Duckham J David Owens Jennifer M Ames 《Journal of the science of food and agriculture》2001,81(5):525-529
Thua nao, a traditional, proteolytic, fermented soybean condiment of northern Thailand, was prepared from cooked whole soybeans by natural flora fermentation. The microbial flora during the fermentation was dominated by Bacillus species. The formation of volatile compounds during the fermentation was studied. In addition, the volatile compounds of two samples of commercial dried thua nao and two samples of commercial Japanese natto were analysed. Fermentation led to a large increase in the concentration of total volatile compounds, from 35 µg kg?1 wet weight in cooked soybeans to 3500 µg kg?1 wet weight in 72 h fermented material. The major volatile compounds in fermented beans were 3‐hydroxybutanone (acetoin), 2‐methlybutanoic acid, pyrazines, dimethyl disulphide and 2‐pentylfuran. Sun drying of 72 h fermented material resulted in the loss of 65% of total volatiles, including important aroma compounds. The commercial dried thua nao samples had low concentrations of total volatile compounds (380 µg kg?1 wet weight). It is suggested that improved drying/preservation methods are needed to retain aroma compounds in the traditional products. The natto samples were devoid of aldehydes, aliphatic acids and esters, and sulphur compounds, whereas the thua nao samples contained a diversity of these compounds. Previous investigators have reported these compounds in natto and it is not possible to suggest the existence of systematic differences between the volatile compounds in traditional thua nao prepared with an undefined, mixed microbial flora and those in natto fermented with Bacillus subtilis. © 2001 Society of Chemical Industry 相似文献
998.
Transesterification of rapeseed oil in the presence of basic zeolites and related solid catalysts 总被引:8,自引:1,他引:7
Elisabeth Leclercq Annie Finiels Claude Moreau 《Journal of the American Oil Chemists' Society》2001,78(11):1161-1165
The transesterification of rapeseed oil with methanol was performed by reflux of methanol over cesium-exchanged NaX faujasites,
mixed magnesium-aluminum oxides, magnesium oxide, and barium hydroxide for different methanol-to-oil ratios. Over cesium-exchanged
NaX faujasites and mixed magnesium-aluminum oxides, a long reaction time and a high methanol-to-oil ratio are required to
achieve both high oil conversion and high yields in methyl esters. However, over a 300 m2/g magnesium oxide, methanol-to-oil ratios and reaction times are significantly reduced to obtain both high oil conversion
and high yield in the methyl esters, particularly when the hydroxide precursor is calcined at 823 K. Finally, preliminary
results with other basic solids such as barium hydroxide have shown a very high activity and a very high yield in esters.
This catalyst is particularly effective since, for a methanol-to-oil ratio of 6, at reflux of methanol and after a reaction
time of only 1 h, the oil conversion is about 80% with a nearly quantitative ester molar fraction.
Part of this work was presented at the 91st AOCS Annual Meeting, San Diego, California, April 2000. 相似文献
999.
Quantitative determination of Ni and V in FCC catalysts monitored by ESR spectroscopy 总被引:1,自引:0,他引:1
Calibration mixtures containing Ni0 and V4+ in the range from 500 to 4000 ppm have been prepared using various supports (silica, alumina, titania and ultrastable Y zeolite
(USY)) with different particle sizes. ESR measurements revealed a linear relation between the impregnated metal amounts and
the registered ESR signal integrals and/or intensities, suitable for the determination of the NiO (reduced to Ni0) and V4+ contents in FCC catalysts, respectively. The amount of NiO in a FCC equilibrium catalyst was determined to about 1300 ppm
of a total of 2500 ppm Ni compound present in this sample, whereas the amount of V4+ was estimated to about 1800 ppm of a total of 2800 ppm vanadium species. Hence, this catalyst contains about 1000 ppm V5+.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
1000.
Eugen Seel Elisabeth Zeeb und Karl Reihling 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1919,37(1-2):1-17
Zusammenfassung Die Ergebnisse der chemischen Untersuchung von Fleisch- und Wurstwaren sind als ausschließliche Grundlage für ihre Beurteilung durchaus ungenügend; denn wir können noch nicht annähernd sämtliche chemischen Einzelbestandteile des Fleisches und der Wurstwaren mittels der im praktischen Laboratorium anwend aren Methoden nachweisen und noch viel weniger diese Einzelbestandteile quantitativ ermitteln. Es läßt sich aber auch im allgemeinen durch die chemische Untersuchung allein nicht feststellen, ob eine unter bestimmten Namen in den Handel gebrachte Ware die in diesem Namen zum Ausdruck gebrachten Fleischbestandteile tatsächlich enthält, wie z. B., ob Leberwurst Leber enthält, ferner ob minderwertige oder verbotene Organund Gewebeteile beigemischt sind oder nicht.Daher ist die mikroskopische Untersuchung, besonders in gerichtlichen Fällen, unerläßlich.Die nur auf mikroskopischem Wege erreichbare Kenntnis der in Fleisch und Wurstwaren enthaltenen Gewebe und Organe erleichtert bezw. ermöglicht die Beurteilung von Fleisch- und Wurstwaren nicht nur in vorgenannter Richtung, sondern sie erleichtert auch sehr wesentlich die Beurteilung ihres Gesamtwertes. Dieser ist verschieden je nach dem Vorhandensein der mikroskopisch nachzuweisenden Gewebe bezw. Organe und nach deren Wassergehalt. Letzterer wiederum ist z. B. bei Muskelfleisch konstanter und liegt in engeren Grenzen als bei den drüsigen Organen; im elastischen Bindegewebe ist er bedeutend niedriger als im kollagenen Bindegewebe oder im Muskelfleisch.In der vorliegenden Arbeit ist der Versuch gemacht, die mikroskopischen Schnitte der wichtigsten in Betracht kommenden Gewebe und Organe in gekochtem Zustande so zu charakterisieren, daß sie in Gemischen einwandfrei identifiziert werden können.Die Technik der mikroskopischen Untersuchung von Fleisch- und Wurstwaren ist unter Angabe bewährter Verfahren eingehend dargestellt. 相似文献