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991.
Rudolf Witte 《Forschung im Ingenieurwesen》1934,5(5):205-211
Ohne Zusammenfassung
VDI
Mitteilung aus der Betriebskontrolle Oppau der I. G. Farbenindustrie A.-G. 相似文献
992.
993.
Rudolf Kunz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1901,4(15):673-683
Ohne Zusammenfassung
Mittheilung aus der k. k. allgemeinen Untersuchungsanstalt für Lebensmittel in Wien. 相似文献
994.
995.
996.
Chi-Tin Shih Yun-Yin Cheng Stephen A. Wells Ching-Ling Hsu Rudolf A. Römer 《Computer Physics Communications》2011,182(1):36-38
The electronic transmission properties of DNA molecules are believed to play a significant role in many physical phenomena taking place in living organisms (Chakraborty, 2007) [1]. Here we study the charge transport (CT) properties of cancer-related genes, including some of the most important tumor suppressors. We find that the changes in averaged CT around the sites of pathogenic and cancerous mutations are statistically smaller than those on sites where pathogenic mutations have not been observed. The results suggest that CT might be an indicator to discriminate between pathogenic and non-pathogenic mutations at an early stage. Mutations which cause little change in CT may be more likely to occur, or more likely to be missed by damage-repair enzymes which probe CT, and are therefore more likely to persist and cause disease. 相似文献
997.
An extended critical review of twenty years of countermeasures used in agriculture after the Chernobyl accident 总被引:1,自引:0,他引:1
Fesenko SV Alexakhin RM Balonov MI Bogdevitch IM Howard BJ Kashparov VA Sanzharova NI Panov AV Voigt G Zhuchenka YM 《The Science of the total environment》2007,383(1-3):1-24
A wide range of different countermeasures has been used to mitigate the consequences of the Chernobyl accident for agriculture in affected regions in Belarus, Russia and Ukraine. The paper comprehensively brings together key data on countermeasure application over twenty years for all three countries and critically evaluates the response to the accident with respect to agriculture. The extents of countermeasures implementation in various periods following the ChNPP accident are documented. Examples of best practices and drawbacks in remediation of affected areas are identified. Data on the effectiveness of agricultural countermeasures have been evaluated and the impact of countermeasures implementation to mitigate consequences of the accident has been assessed for the period 1986-2006. Implementation of agricultural countermeasures averted 30-40% of the internal collective dose that would have been received by the residents of affected regions without the use of countermeasures. The current situation in agriculture of areas subjected to contamination following the Chernobyl accident is described. Current and future needs for remediation, including a consideration of various strategies of rehabilitation of affected areas are presented. 相似文献
998.
Processes with thermal treatment of starch-based materials for biologically degradable packaging products are analyzed here.
The paper describes experiments on thermal forming of potato starch-based water suspensions in a closed mold at elevated pressures
and temperatures of walls heated up to 200 °C. The time course of temperatures and also the sample expansion were detected
by a network of thermocouples and compared with the pressure recorded inside the mold. Evolution of temperature profiles enables
the estimation of time courses of sample expansion. Experiments with marking particles show that the crust sticks to the heater
walls and only the sample core expands. Temperatures and pressures are closely related during expansion and the free water
evaporation stage. Experiments confirm that temperatures are more or less uniform in the longitudinal direction and that the
time profiles of temperature and pressure are characterized by peaks corresponding to perforation and recovery of foamed structure. 相似文献
999.
Engel E Santarelli F Vasold R Ulrich H Maisch T König B Landthaler M Gopee NV Howard PC Bäumler W 《Analytical chemistry》2006,78(18):6440-6447
Tattooing is a widespread process of puncturing pigments into skin, whereas the resulting concentration inside the skin remains unknown. Many tattoo colorants are organic pigments, such as azo pigments, manufactured for other uses. To remove tattoos from skin, laser pulses at very high intensities are applied to the skin to destroy the tattoo pigments. Recent investigations have shown that several azo compounds are cleaved by laser light leading to potentially toxic or carcinogenic compounds. To assess the risk of tattooing and laser treatment of tattoos, the concentration of the pigments and their decomposition products in the skin must be determined. Therefore, an extraction method was established to determine the concentration of tattoo pigments and decomposition products quantitatively. The extraction of two widely used azo compounds, Pigment Red 22 and Pigment Red 9, and their laser-induced decomposition products, 2-methyl-5-nitroaniline, 4-nitrotoluene, 2,5-dichloraniline, and 1,4-dichlorobenzene, was accomplished using recovery experiments and HPLC-DAD technology. Despite the poor solubility of the pigments, a nearly complete recovery from aqueous suspension (> 92%) or lysed skin (> 94%) was achieved. The decomposition products were extracted from aqueous suspension or skin showing a recovery of up to 100%, except for the very volatile 1,4-DCB. 相似文献
1000.
Graeme Moad Katherine Dean Lex Edmond Natalia Kukaleva Guoxin Li Roshan T. A. Mayadunne Rudolf Pfaendner Armin Schneider George P. Simon Hendrik Wermter 《大分子材料与工程》2006,291(1):37-52
Summary: Poly(propylene) (PP)‐clay nanocomposites were prepared from unmodified montmorillonite clays (NaMMT), with poly(ethylene oxide)‐based nonionic surfactants as dispersants/intercalants/exfoliants. The primary objective of this research was to find dispersants that (a) allow PP nanocomposites to be formed by direct melt mixing; (b) are effective with unmodified clays and (c) comprise of only a minor component with respect to both the clay and the overall composition. Linear, branched, gemini and sugar‐based surfactants and structures containing poly(dimethyl siloxane) and poly(methyl methacrylate) blocks were examined. These additives were found to be effective in breaking down the clay agglomerates to tactoids, giving some expansion of the clay structure and partial exfoliation and providing substantially improved clay dispersion. The properties of the derived nanocomposites depend on the level of additive and its structure. Tensile and impact properties show significant improvement over the precursor PP. Also notable are the significantly better thermal and thermo‐oxidative stabilities, as compared to both PP and “clay alone” composites. For optimal properties, it is both necessary and desirable that the surfactant should only be a minor constituent (20–50%) of the composition, with respect to the clay. A preferred surfactant is linear PE‐block‐PEO, with a short PEO block and an alkyl chain with approximately 30 carbon atoms (C30).