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91.
广泛收集了欧盟、北美和日本这些我国电子电气设备主要出口国家及地区的电子电气设备有害物质相关法规,对之进行了分析研究。并在这些研究的基础上。提出了有关电子电气设备有害物质合格评定以及在我国推行环境化设计的建议。 相似文献
92.
采用HPLC法测定甲基多巴中3-甲氧基甲基多巴及其它有关物质的含量,并与药典中的TLC法进行对比.色谱条件为:色谱柱:phenomenex LUNA C18分析柱(4.6 mm×250 mm,5um),流动相:乙腈-2.0%磷酸氢二钠水溶液,加入磷酸调节pH至5.0(10∶90),流速:1 mL/min,检测波长:280 nm,进样量:20μL.该方法中甲基多巴和3-甲氧基甲基多巴及氨基丙腈分离度良好,线性范围分别为0.002~0.1μg(r=0.999 97),检测限:1 ng;0.008~0.2μg(r=0.999 8),检测限:2 ng.本法简单、专属,能有效快速地控制产品质量. 相似文献
93.
综述了山地土壤坡向性分异的研究概况,包括土壤生物积累和盐基淋溶的坡向差异,以及坡向对土壤垂直带谱结构的影响。已有研究大多集中在山地土壤垂直带谱的坡向分异,可将其归纳为山地迎风坡与背风坡和阴、阳坡分异两种主要情况。同时,针对目前有关山地土壤坡向性研究的不足,提出了今后研究的重点:从山体不同坡向的对应高度出发,运用现代地理研究方法,研究山地土壤多种属性的坡向性分异及其生产生态意义。 相似文献
94.
Sebastien Narses Faten Sadaka Claire‐Hélène Brachais Jean‐Pierre Couvercelle 《应用聚合物科学杂志》2013,129(5):2891-2904
The coloration of different polymer films (from commodity and packaging films to performance films) by contact with various food coloring substances was evaluated. For this purpose, both solubility parameters as a prediction tool, and immersion experiments for time range between 24 and 1000 h were established. The two predicting tools are the Hoy and Hoftyzer‐Van Krevelen (HVK) methods. For PE and PP, HVK's method is preferred for predicting coloration. Neither of the HVK's and Hoy's methods was able to establish a coloration prediction for PET while both methods could predict the staining of PEEK. The coloration of partially and fully fluorinated polymers is well predicted by the Hoy's method. The behavior of PP/PA and PP/PA/PP multilayer films was also studied. Crystallinity degree of polymers, temperature and concentration of coloring molecules are also important parameters, which are not taken into account in solubility theories. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
95.
J. A. Alburquerque I. Bautista‐Carrascosa A. Lidón R. García‐de‐la‐Fuente J. Girbent M. Abad J. Cegarra 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):918-926
BACKGROUND: The production of biodegradable wastes and their disposal cause a major financial problem in many industrial activities. Co‐composting was thought to be a feasible alternative for disposing of a strongly alkaline waste from the pharmaceutical industry (AW), mainly consisting of animal fats and partially hydrolysed proteins in a stable emulsion. The AW was added gradually, during the early phase of the composting process, to a substrate made up of ‘alperujo’ (AL), the wet, lignocellulosic, solid by‐product of the olive oil industry, and fresh horse manure, which was added to improve the physical structure of the composting substrate. RESULTS: The addition of AW reduced organic matter degradation during composting, enriched the amount of organic compounds in the water‐ and alkali‐soluble fractions and increased mineral salt contents. Thus, significantly higher electrical conductivity, humification indices and contents of organic matter, P, K and Na were recorded in the end‐composts resulting from AW treatments. However, the application of one AW‐based compost led to soil N immobilisation, as revealed by an incubation experiment, which must be considered in order to avoid potential N starvation in the short term. CONCLUSION: According to these results, composting can be used as a disposal alternative for AW, leading to end‐products with potential uses as organic amendments or fertilisers for agricultural systems. In addition, these composts could be used to produce alternative liquid organic fertilisers, based on the extraction of their humic‐like fraction. Copyright © 2009 Society of Chemical Industry 相似文献
96.
Yu-Ting Chiou 《Desalination》2010,250(2):648-396
Low-pressure membrane processes, such as ultrafiltration (UF), are effective for treating algae-laden eutrophic source waters. However, fouling caused by algae excreted organics can be a major obstacle to the smooth operation of membrane processes. In this study, three algae species, with a similar cell size and shape, but a different amount of extracellular polymeric substances (EPS), were selected. The characteristics of the bound EPS, including its amount and constituents, mainly polysaccharide and protein, were analyzed. Cell suspensions were filtered through a dead-end stirred cell with a regenerated cellulose UF membrane. Based on the observations of permeate flux decline at higher transmembrane pressure (TMP) and critical flux values, it can be concluded that algae cell EPS do affect membrane fouling, and the constituents of EPS may also play a role. 相似文献
97.
The introduction of acid-tolerant heterotrophic microorganisms into sludge bioleaching systems has been proven effective in improving sludge bioleaching processes, and such positive effect is mainly attributed to the biodegradation of low molecular weight organic acids or sludge dissolved organic matter (DOM) toxic to Acidithiobacillus species by the heterotrophic microorganisms introduced. Here we report that elevated dissolved CO2 concentration and resulting extracellular polymeric substances (EPS) in bioleach solution due to the incorporation of heterotrophic microorganisms also play important roles in improving sludge bioleaching. It was found that in tannery sludge bioleaching system coinoculated with Rhodotorula mucilaginosa R30 and Acidithiobacillus species, dissolved CO2 concentration in bioleach solution can be elevated from 0.23-0.54 mg/L to 0.76-1.01 mg/L compared to the control inoculated only with Acidithiobacillus species. Correspondingly, the distinct degradation of sludge DOM was also observed in this experiment. It was experimentally demonstrated that the accumulation of CO2 did greatly enhance the growth of Acidithiobacillus thiooxidans and the decrease rate of pH in the medium. In addition, EPS derived from R. mucilaginosa R30 could bind readily Fe3+ in bioleach solution with maximum binding capacity (MBC) of 0.82 mg Fe3+ by per mg DOC of EPS secreted and the oxidization activity of EPS-bound Fe3+ was decreased but not totally inhibited, indicating that the formation of soluble EPS-Fe(III) complexes enhances, to a certain extent, bioleaching efficiency due to maintaining Fe3+ level in solution by inhibiting Fe precipitation occurrence. 相似文献
98.
A. G. Tumanovskii 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2005,39(2):95-103
The main legislative documents in the field of environmental protection and ecological standards for newly developed equipment of thermal power plants (TTP) of Russia are presented. Problems of raising the efficiency TTP and reducing harmful emissions are considered. Modern methods and process for lowering nitrogen oxide emissions for different kinds of fuel, fields of application of sulfur-removing technologies, and ways for updating fly-ash collectors are discussed. The tendency to tightening of standards regulating the volume of contaminating substances is shown. Data on TTP wastewaters and maximum permissible concentrations (MPC) of primary contaminants are presented. Reduction of atmospheric emissions and of contaminating due TTP wastewaters is estimated until 2010.__________Translated from Elektricheskie Stantsii, No. 1, January 2005, pp. 17–27 相似文献
99.
Effects of surface active substances, natural and synthetic, in selected samples of seawater, river water and industrial effluents on the oxidation-reduction processes of cadmium have been studied by electrochemical methods and compared with the behaviour of different model compounds.Kinetic parameters, transfer coefficient α and apparent standard rate constant of the cadmium electrode reaction have been estimated from the shape and the height of the corresponding differential pulse voltammograms using theoretical curves obtained by digital simulation of the electrode process. The measure of the inhibition effect of surface active substances on the electrode reaction of cadmium was expressed in terms of the ratio of the rate constants determined in the presence and in the absence of surface active substances.It was found that the degree of inhibition depends on the concentration and type of surface active substances and on the pH of solution. 相似文献
100.
Terbium(III) stearoylanthranilate has been prepared as a high property Z-type Langmuir-Blodgett (LB) film on various substrates by a vertical transfer process. The UV-visible absorption spectra and the low angle X-ray diffraction peaks have been collected in order to investigate the molecular arrangement and aggregation in the LB films. The average molecular orientation in multilayer stacking was determined by Attenuated Total Reflection Spectroscopy. The influence of the chemical environment of terbium within the LB films on the luminescence properties has been discussed. 相似文献