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41.
总有机碳含量(TOC)是评价页岩生烃能力和页岩油气藏的一个重要指标,目前国内外利用地震资料直接定量预测TOC的报道很少,因此,有必要对地震预测TOC的方法作进一步的研究。为此,以四川盆地焦石坝地区为例,从岩心实测TOC出发,通过TOC与地球物理参数交会分析,寻找到TOC敏感地球物理参数——密度,并建立密度与TOC之间的最佳拟合方程,得到计算总有机碳含量的经验公式;结合叠前地震反演获得的密度体便可计算出TOC数据体,从而达到定量预测页岩TOC的目的。将改进的预测方法应用于四川盆地焦石坝地区海相页岩气勘探,结果表明:①利用叠前同时反演直接求得的密度体避免了累计误差,稳定性好,多解性少,结果可靠,为精细定量预测TOC提供了基础保证;②预测的TOC与实测结果吻合程度高,相对误差较小。结论认为,该技术在四川盆地海相页岩气勘探中具有广阔的应用前景。  相似文献   
42.
The removal of Ag+ or AgNPs released from nano-products or effluent of WTP is important to reduce the potential risk of AgNPs. In this work, we prepared bimodal nanoporous silica (BNS) to compare the removal efficiency of Ag+ and AgNP with unimodal nanoporous silica (NS). To determine the adsorption capacity of Ag+ and AgNPs on NS and BNS, isotherm and kinetics studies was carried out at different concentrations. The results showed BNS with a bimodal nanoporous structure and a large external surface showed a higher uptake capacity and faster adsorption rate.  相似文献   
43.
煤层气发电是煤层气利用的重要途径之一,但煤层气发电排放的高温尾气中含有大量的氮氧化物(NO_x),会对环境造成污染,需要对其进行脱硝处理,而高温烟气(约500℃)又不宜用V_2O_5/TiO_2蜂窝式催化剂进行直接脱硝处理。为此,在分析比较煤层气发电高温烟气与燃煤发电烟气差别的基础上,应用纳米组装和灌注法研制了GJ-HC-5型催化剂,并通过室内实验确定了脱除NO_x的最佳温度窗口(400~600℃)。之后,在某煤层气电厂进行中间试验,将发电机组高温烟气直接通入到SCR一体化装置进行脱硝处理,在SCR反应器进出口处连续监测,进口NO_x浓度约为620 mg/m~3,出口监测浓度约为20 mg/m~3,对烟气中的NO_x的脱除率始终保持在90%以上。试验结果表明,所研制的高温SCR催化剂符合实际烟气温度条件,且制备方法简单,是一种可行的煤层气发电高温烟气的脱硝方法。  相似文献   
44.
45.
The influence of different types of iron salts (i.e., ferrous or ferric cations with sulphate, nitrate or chloride anions) on the reaction between coarse thermomechanical pulp and acid hydrogen peroxide (Fenton chemistry) was studied when the initial pH was 3.2 and 5.3. Also, ferric ions chelated with EDTA or EDG at different molar ratios were compared with ferrous sulphate when the initial pH was extended from about 3 to 8. Different anions of ferric ion salt gave a similar catalytic effect. At an initial pH of 7–8, the ferric-EDTA catalyzed reaction resulted in similar or higher hydrogen peroxide consumption and more detectable hydroxyl radicals than the ferrous sulphate catalyzed reaction, but less reaction with the pulp was indicated. Between pH 5–8, using Fe-EDG as a catalyst gave higher hydrogen peroxide consumption and more detectable hydroxyl radicals than if using ferrous sulphate; however, the measured effect on the pulp was similar or less.  相似文献   
46.
Nowadays, aflatoxin B1 (AFB1) could be considered as one of the most hazardous mycotoxins for humans, and nuts comprise one of the major responsible food categories for human exposure to this mycotoxin. Thus, complete elimination of AFB1 or reduction of its content in nut foods, such as pistachio attracted lots of attentions. In the current study, the efficacy of roasting process by incorporation of lemon juice and/or citric acid on the reduction of AFB1 in contaminated pistachio nuts (AFB1 at two levels of 268 and 383 ng/g) was investigated. Significant degradation of AFB1 (up 93.1% for AFB1) was recorded by applied treatment protocols. Although roasting of 50 g pistachio nuts with 30 ml water, 30 ml lemon juice and 6 g of citric acid at 120 °C for 1 h resulted to a significant degradation (93.1 ± 8.2%) of AFB1, this treatment altered the desired physical properties. Roasting with 30 ml water, 15 ml lemon juice and 2.25 g of citric acid at 120 °C for 1 h reduced the level of AFB1 in 49.2 ± 3.5% of the initial level without a noticeable change in desired appearance of pistachios. Hence, a synergistic effect between heating and lemon juice/citric acid in order to AFB1 degradation was observed. It could be concluded that roasting process with lemon juice and citric acid could be applied as a useful and safe degradation method of AFB1 in naturally contaminated pistachio nuts.  相似文献   
47.
A simple and convenient HPLC-FD detection method for ochratoxin A (OTA) with a high detection limit and a short run time has been developed. OTA has been found in most samples of Chinese market wine, including domestic and imported wines, but the content was not very high. Only a few wines showed an OTA content that exceeded the EC and OIV limits, indicating that most Chinese market wines were safe. The OTA intake for Chinese from wine was 0.017 ng/kg (bw) per day, which was lower than the SCF and JECFA limits and also lower than in many other countries. This was mainly due to the low per capita wine consumption in China, but it is still necessary for the Chinese government and wine makers to monitor OTA levels in wine and to establish relevant regulations. An egg white treatment (0.20 mg/mL, 48 h) was the best removal method for OTA.  相似文献   
48.
The organic olives from Çine-Ayd?n (Turkey) were washed with tap or ozonated water for 2 and 5 min, respectively, and pressed to olive oil. The effects of wash treatments on fatty acid composition and several quality parameters of the oils were determined. The maximum values after 2-min ozonated water washes were 9.58 meqO2/kg, 0.73%, 2.44 and 0.16 for peroxide, free acid, K232 and K270 values, respectively, which were under the standard limits for extra-virgin olive oil. Five min of ozonated water washes also yielded acceptable results, except for a slight excess on K232 value. Ozonated water washes had almost no effect on fatty acid composition.  相似文献   
49.
This paper reports fabrication, optimization and characterization of multifunctional biocapsules with immobilized enzyme using a layer-by-layer configuration and their application for removal of phenol and bisphenol A (BPA). The method is based on the combined use of enzymatic oxidation of the BPA and subsequent binding of the reaction product onto a chitosan core biopolymer. This platform has multiple functions including: (1) enzymatic degradation of BPA, (2) adsorption of the degraded compound within the core material, (3) colorimetric quantification and (4) magnetic capabilities. We examined various configurations of core/shell structures of alginate and chitosan and determined the stability and the optimum conditions in which these structures provide the most effective removal capacity. The amount of BPA that can be removed per capsule is 5.6 ppm while phenol can be removed up to 10 ppm per capsule within 15 h.  相似文献   
50.
In order to quickly remove nitrate from aqueous solution, a magnetic strong base quaternary ammonium anion exchange resin (MAER) has been successfully designed and synthesized. The physicochemical properties of the MAER as well as its adsorption ones for nitrate removal were investigated in detail. A series of batch experiments were carried out to evaluate the effects of several factors on removal efficiency of nitrate, such as retention time, resin amount and initial nitrate concentration. Compared to the commercial Purolite A300 and D213, the equilibrium time for the adsorption process using MAER was only around 20 min, which is significantly less than that of two ones mentioned. Furthermore, the kinetic process of nitrate sorption on MAER could be well described by both pseudo-first-order and pseudo-second-order models. In addition, the results of batch experiments can be better fitted by the Langmuir and Freundlich adsorption isotherm models. Most importantly, the effects of competing ions on nitrate removal followed the order as: SO42− > Cl > HCO3. These results are of significance in guiding the development of novel resins with the rapid nitrate removal rate from aqueous solution, which would improve efficiency and save energy greatly.  相似文献   
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