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991.
一种陆基微生物燃料电池供电的无线传感器网络 总被引:1,自引:0,他引:1
Aquatic Microbial Fuel Cell(AMFC) must be inoculated and work in water environment. Terrestrial Microbial Fuel Cell(TMFC) can overcome the shortcoming. In order to realize the practical application of TMFC, a single-hop Wireless Sensor Network(WSN) powered by a TMFC experimental setup is designed and established. Power generation performance of the TMFC and sensor data acquisition, wireless transmission and processing of the WSN are tested by experiments. Experimental results show that the proposed TMFC can drive the single-hop WSN periodically, which validates the feasibility of TMFC powered WSN. 相似文献
992.
可溶性微生物产物(Soluble Microbial Product,SMP)是活性污泥污水处理体系中的微生物的重要代谢产物,是污泥絮体形成以及保证体系稳定运行的关键因素之一.本文对CASS和A2O工艺产生的脱水污泥进行了好氧和厌氧培养,提取了SMP和胞外聚合物(Extracellular Polymeric Substances,EPS),表征并探究了两者对含偶氮染料废水的微生物燃料电池产电性能的影响,以及对脱色效率的改善情况.红外分析表明,不同工艺和培养方法得到的SMP和EPS的成分构成相似度很高;PACl沉降试验表明,SMP中的大分子物质含量普遍低于EPS.SMP和EPS均可提升微生物燃料电池的电压,最高可达130mV,且两者均可提高偶氮染料的脱色率,最高可达93%.这些研究表明SMP和EPS有作为染料废水产电资源化助剂的价值. 相似文献
993.
从中国石油长庆石化公司附近的油泥中分离筛选出4株石油降解菌,用于组建降解原油的混合菌体系.在等接种量培养条件下,单菌株对石油烃的降解率达到41.83%~54.87%,而混合菌降解效率高于单菌株,达到64.27%.不同微生物在降解过程中起着不同的作用.居植物柔武士菌(Raoultella planticola)具有脱烷基功能,对一些支链烃有降解效果;蜡状芽孢杆菌(Bacillus cereus)既可以氧化末端烯烃,又可以降解环烷烃;克雷伯氏菌(Klebsiella variicola)是优势菌种,不仅具有以上3种降解功能,还可以降解炔烃;粘质沙雷氏菌(Serratia marcescens)和蜡状芽孢杆菌(Bacillus cereus)均能氧化不饱和醛基.4种单菌株可能存在相互抑制作用,不宜混合培养降解环烷烃.本研究为石油烃的降解机制和筛选功能微生物等方面奠定了理论基础. 相似文献
994.
Of various chopped vegetables tested,Allium spp. high in propyl-containing alkyl sulfides (e.g.,cepa group) caught the most onion flies in trapping tests in the field. Fly catches to chopped onion increased with bait quantity. Attractancy of chopped onion changed dramatically during aging in the field; catch increased over the first few days, peaked at ca. fivefold over fresh material by 3–5 days, and then declined sharply. This age-dependent increase in attraction was not seen for garlic (known to have antimicrobial properties) nor with chopped onion mixed with chopped garlic. These data suggested that attraction of onion flies to onions was strongly influenced by microbial activity associated with decomposing onions. The bacteriumKlebsiella pneumoniae was identified as a major colonizer of onions maximally attractive to onion flies. This increased attraction is not due to the previously reported microbially produced volatiles ethyl acetate and tetramethyl pyrazine.Diptera: Anthomyiidae.Paper No. 11047 of the Michigan State University Agricultural Experiment Station. 相似文献
995.
996.
微生物资源与氨基酸的生产和应用 总被引:4,自引:0,他引:4
微生物资源具有多样性、易变性、生长快等特征,与动、植物资源相比存在许多未知数。对微生物生产氨基酸进行了概述.提出了应积极研究、开发和利用产氨基酸的微生物资源,拓展氨基酸产品,重组具特殊优良性能的氨基酸的生产菌种,大力发展有特色的氨基酸试剂。 相似文献
997.
The interactions between three polynuclear aromatic hydrocarbons (PAHs), namely fluorene, naphthalene and anthracene, and three fractions of a soil, namely fulvic acid (FA), humic acid (HA) and humin/inorganic fractions, were studied experimentally. Prepared PAH + soil fraction binary mixtures, with PAH concentrations ranging over 0.8–7 mass%, were tested using a differential scanning calorimeter (DSC) over a temperature range of 20?390°C. The DSC thermograms for the PAH + HA mixtures showed distinctly different characteristics compared to mixtures with the other two soil fractions, where the endothermic peak for the vaporization of the PAH was absent. With the aid of vapour-liquid flash calculations, the lack of the boiling point peak is interpreted to be due to the liquid-phase miscibility of the PAHs and the HA fraction. Implications of the DSC results on the design and performance of the thermal desorption process are discussed. 相似文献
998.
Sterile and microbe reinfested Cecil Ap and Bt soil materials amended with 0 to 5 µmol/g of ferulic acid,p-coumaric acid,p-hydroxybenzoic acid, or vanillic acid were extracted after varying time intervals with water, EDTA, or NaOH to characterize sorption of cinnamic and benzoic acid derivatives and to determine the effectiveness of water and EDTA extractions in estimating concentrations of free and reversibly bound phenolic acids in soils. Basic EDTA (0.5 M, pH 8) extractions and water extractions provided good estimates of both free and reversibly bound cinnamic acid derivatives, but not of benzoic acid derivatives. Neutral EDTA (0.25 M, pH 7) and water extractions, however, were effective for both cinnamic and benzoic acid derivatives Rapid initial sorption of both cinnamic and benzoic acid derivatives was followed by slow long-term sorption of the cinnamic acid derivatives. Slow long-term sorption was not observed for the benzoic acid derivatives. The amount of sorption of phenolic acids in soil materials was directly related to the concentration of phenolic acids added to soil materials. The addition of a second phenolic acid to the soil materials did not substantially affect the sorption of each individual phenolic acid. Sodium hydroxide extractions, which were made only after phenolic acids in phenolic acid-amended and non-amended soil material were depleted by microbes, confirmed that neutral EDTA and water extractions of soils can be used to make accurate estimates of baseline (residual) levels of free and reversibly bound phenolic acids available to soil microbes and, thus, potentially to seeds and roots.The use of trade names in this publication does not imply endorsement by the North Carolina Agricultural Research Service of products named, nor criticism of similar ones not mentioned. 相似文献
999.
Bioventing is conducted on one-dimensional soil columns.A numerical model is developed for simulating the mass exchange,advective and dispersive transport and biodegradation of toluene.The model parameters are estimated independently through laboratory batch experiments,or from literature.Simulations are found to provide reasonable agreement with experimental data.Experimental results show that toluene removal due to biodegradation is more important at the later stage.The total cleanup time when NAPL(non-aqueous phase liquid)phase exists was twice more than that without NAPL.Sensitivity analysis of parameters suggests that model predictions are mainly dependent on mass transfer coefficient and microbial parameters,such as the half-saturation coefficient and maximum specific substrate utilization rate. 相似文献