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31.
32.
Yew Pei Ling Chee-Heong Ooi Akihiko Matsumoto Fei-Yee Yeoh 《Ceramics International》2018,44(2):1411-1419
Water sludge from Sungai Dua Penang fresh water processing plant has been successfully converted into functional pottery clay with improved physicochemical behavior and properties. Water sludge was generally made of kaolinite mineral that consisted of silica and alumina. At 7 h of milling duration, water sludge demonstrated a narrow particle size distribution at the size range of 107–150 µm. Water sludge owned a specific surface area of 27 m2/g with 8.8 nm (diameter) pore size and 0.05 cm3/g pore volume. Plasticity of clay body increased when clay formulation involved fine particles, e.g. water sludge or bentonite, which promote water adsorption ability. Fine particles with large surface area and better compaction also explained the enhanced hardness of pottery clay. The incorporation of clay minerals such as bentonite and sodium silicate into the formulation has facilitated metals immobilization within the clay body. Final clay product has a terra cotta color and performed a uniform shrinkage without obvious fracture. The fabrication of pottery wares from water sludge with minimized metals leakage has not only higher reutilize value but also a cost effective green method for handling waste and environmental issues. 相似文献
33.
为更好地回收含油污泥(即油泥)中可用资源,国内外油泥资源化处理方法不断更新和突破,并在室内实验研究阶段取得较好的处理效果。本文从油泥的高温热处理法、常温法、低温冻融法三个方面综述了热解、微波、萃取等油泥资源化处理方法的研究进展、优缺点以及适用条件等。热解法油品回收率达95.8%,具有油泥处置彻底、油品回收质量高的特点。电动力学法处理油泥,油泥减量化达44.3%,采用浮选法,油泥减量化达95%,两种方法均具有操作简单、易实施、适合大批量处理的特点,工程化应用潜力较大。油泥来源不同,性质各异,采用单一技术难以实现大量油泥的资源化和无害化目标。多项技术联合,如热解法联合浮选法或电动力学法处理大规模油泥能提高油品回收率和质量,降低残油率和处理成本,将成为油泥资源化处理技术的发展方向。 相似文献
34.
The disintegration of waste active sludge was investigated by photo‐Fenton processes. A batch study was conducted to evaluate parameters, such as Fe2+ and Fe0 ions and H2O2, governing the activated sludge integration by the photo‐Fenton process. Under optimum conditions, the concentration of soluble chemical oxygen demand (SCOD) with the classical Fenton process (CFP) increased very rapidly in the first five minutes due to the sufficient presence of reaction components in the medium, and then the rate of increase declined. In the modified Fenton process (FTP), the SCOD concentration increased more slowly as metallic iron powder must first be dissolved. The photo‐Fenton process proved to be a feasible and efficient process for the disintegration of waste sludge. 相似文献
35.
大幅减少炼油生化剩余污泥对降低企业污泥处理和处置费用、保护生态环境意义重大。考察了炼油生化剩余污泥催化深度减量SMR技术工业化的处理效果,运行结果表明:对含水率98.3%的炼油生化剩余污泥,经过SMR污泥减量装置的处理,污泥脱水性能得到显著改善,脱水残渣平均含水率57.1%、污泥量减少99.4%、挥发性悬浮物平均去除率78.3%、消解液BOD5/COD比为0.31,达到了污泥深度减量化的目的。 相似文献
36.
37.
Mechanical sludge disintegration for the production of carbon source for biological nutrient removal 总被引:6,自引:0,他引:6
Kampas P Parsons SA Pearce P Ledoux S Vale P Churchley J Cartmell E 《Water research》2007,41(8):1734-1742
The primary driver for a successful biological nutrient removal is the availability of suitable carbon source, mainly in the form of volatile fatty acids (VFA). Several methods have been examined to increase the amount of VFAs in wastewater. This study investigates the mechanism of mechanical disintegration of thickened surplus activated sludge by a deflaker technology for the production of organic matter. This equipment was able to increase the soluble carbon in terms of VFA and soluble chemical oxygen demand (SCOD) with the maximum concentration to be around 850 and 6530 mgl(-1), for VFA and SCOD, respectively. The particle size was reduced from 65.5 to 9.3 microm after 15 min of disintegration with the simultaneous release of proteins (1550 mgl(-1)) and carbohydrates (307 mgl(-1)) indicating floc disruption and breakage. High performance size exclusion chromatography investigated the disintegrated sludge and confirmed that the deflaker was able to destroy the flocs releasing polymeric substances that are typically found outside of cells. When long disintegration times were applied (>or=10 min or >or=9000 kJkg(-1)TS of specific energy) smaller molecular size materials were released to the liquid phase, which are considered to be found inside the cells indicating cell lysis. 相似文献
38.
Characterisitcs of copper-binding, in the soluble fraction of a digested sewage sludge, were determined using ion-selective electrodes. Results showed that ion exchange with protons is a principal component in copper binding and that the soluble organic matter has a cation exchange capacity of 8.86 m-equiv g−1 at pH 6.5. A pH-dependent exchange constant, defined in terms of mole fractions of exchange components, describes the data in the pH range 2–8 and is independent of both pH and the extent of exchange in the range 5.5–8. Supplementary data include acid/base titration curves and simple kinetic measurements. Anion uptake is insignificant in the pH range 2.5–7. A model of the aqueous phase of a sewage sludge, containing soluble organic matter with only copper and protons as competing ions, predicts that at pH 7 over 99% of the copper present will be bound to the soluble organic matter. 相似文献
39.
Twelve independent batch experiments (<9h) with fresh municipal activated sludge were conducted to assess the occurrence and the mechanisms of deflocculation under a temperature shift from 30 to 45 degrees C. In each experiment, a transient reactor (2 L) was subjected to the temperature shift and a control reactor was operated at a constant temperature of 30 degrees C. The occurrence of deflocculation was demonstrated by the increase in turbidity and in the concentrations of biopolymers in the sludge supernatant from the transient reactor. The maximum levels of proteins in the supernatants ranged from 53 to 81 mg/L, for DNA from 34 to 36 mg/L, for humic compounds from 20 to 40 mg/L, and for carbohydrates from 21 to 31 mg/L. All the biopolymer concentrations in the control reactor remained below 5-10 mg/L. The release of biopolymers was accompanied by an increase in sludge supernatant conductivity (16-32% increase, up to 1.20 mS/cm), soluble chemical oxygen demand (from 129 to 440 mg/L), total suspended solids (>25 mg/L up to 128 mg/L), and a decrease in the mixed liquor volatile suspended solids (up to 11%). The temperature shift was also found to inhibit microbial metabolism by reducing the sludge biomass substrate removal capacity, as measured by oxygen-uptake rates. The temperature shift had a marginal effect causing sludge lysis (as an increase in beta-galactosidase activity) and had no significant impact on sludge viability (live/dead ratio of bacterial cells). It was concluded that sludge deflocculation under a temperature shift from 30 to 45 degrees C involves the solubilisation of extracellular polymeric substances from the flocs and likely also floc fragmentation. In addition, sludge deflocculation and the inhibition of microbial metabolism explain the poor treatment performance observed in previous continuous reactors under similar temperature shifts. 相似文献
40.
Characteristics of sludge developed under different loading conditions during UASB reactor start-up and granulation 总被引:8,自引:0,他引:8
Sludge characteristics available inside the reactor are of vital importance to maximize advantages of UASB reactor. The organic loading rate and sludge loading rate applied during start-up are among the important parameters to govern the sludge characteristics. Effects of these loading rates on the characteristics of the sludge developed are evaluated in six laboratory scale UASB reactors. The sludge characteristics considered are VSS/SS ratio of the sludge, sludge volume index, specific gravity, settling velocity and metal contents of the sludge developed under different loading rates. The experimental results indicate that, for developing good characteristics sludge, during primary start-up from flocculent inoculum sludge, organic loading rate and sludge loading rate should be in the range of 2.0-4.5 kg COD/m3 d and 0.1-0.25 kg COD/kg VSS d, respectively (chemical oxygen demand, COD). Proper sludge granulation and higher COD removal efficiency will be achieved by these loading rates. 相似文献