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1.
Preozonation on landfill leachate was carried out. COD removal rate has an obvious inflection at ozone dosage 0.186 mgO3/mgCOD in ozonation process. Seven sets of identical O3-SBR combined process under different ozone dosages were studied. The results indicated that the best COD removal rate of synergetic effect is also at 0.186 mgO3/mgCOD. New organic substances produced after ozonation was confirmed by an excitation-emission matrix (EEM). Carbon dioxide production increased from 36.3 mg to 75.7 mg after ozonation, confirming that biodegradability of refractory organics in landfill leachate was enhanced. All the arguments indicated that the inflection point of COD removal by ozonation has a great significance for preozonation.  相似文献   
2.
Manganese oxides on titanium dioxide were prepared by impregnation method at various calcination temperatures and by deposition-precipitation method and the catalysts were characterized using TG-DTA, XRD, XPS, and N2 adsorption. Various oxidation states for manganese were obtained and activity towards ozone decomposition inside a nonthermal plasma catalysis reactor was investigated. Activity tests show that with increasing manganese oxidation state, the greater the degree of ozone decomposition inside the reactor. MnOx/TiO2 prepared by impregnation method calcined at 350 °C showed the highest decrease in ozone concentration.  相似文献   
3.
注CO2驱油作为一种有效提高采收率的方法,在油气田开采中已经占据越来越重要的地位。文章阐述了CO2驱油机理,介绍了对应的驱油方式,其中着重系统地总结出了现行测定及评价注CO2驱参数的各种室内试验方法。  相似文献   
4.
海上油田低品质、难动用储量所占比例逐渐增加,其中低渗透油藏储量已达20%,如何动用开发低渗透油田储量对海上石油而言是一个艰巨的挑战.针对海上低渗油田W-6开展了注CO2气体开发的可行性研究.通过与二氧化碳驱筛选标准对比,认为W-6油田的油藏地质条件基本符合二氧化碳驱筛选标准.在此基础上对W-6油田的流体相态进行模拟研究,为数值模拟组分模型提供了流体状态方程,之后通过数值模拟方法对注气井位、转注气时机、注气方式及混相可能性进行了研究,最后的优化注气方案表明,W-6油田注CO2后虽然不能达到混相,但仍能提高采收率6.1%.  相似文献   
5.
以光反射聚碳酸酯为主线,分析了作为反光板材料的反射性能的本质及其相关的影响因素,以作为不同反射要求的使用要求的配方更改作为指引.  相似文献   
6.
Gas emission during combustion of mixed tropical wood, bamboo, oil palm trunk, acacia, and rubber wood have been investigated by using TG–MS in presence of oxygen as well as FTIR. The weight decreasing profiles and the gas formation rates of oil palm trunk was significantly different among the samples although their elemental composition was almost the same from biomass samples. It was found that H2O is the main product formed for all samples. The evolving rates of the gaseous products during the combustion and infrared spectrums such as CO, H2O, CO2, CH4 and COOH+ were found. The DTG curves spectrums for biomass present four overlapping peaks.  相似文献   
7.
金属铝基由于其良好的散热性能,广泛应用于LED方面;但随着PCB技术进一步向短、小、轻、薄的方向发展,其平面安装技术在安装空间方面受到了极大的限制,因此,如何实现金属基板三维折叠安装成为业界新的研究课题。对铝基+软硬结合板的制作工艺进行了可行性探讨,通过铝基表面复合处理工艺+纯胶预贴局部撕胶十二氧化碳激光切割技术有效实现了金属铝基与挠性电路的有机结合,满足了客户对金属基板实现三维安装的特种需求。  相似文献   
8.
This paper describes a method to design air quality monitoring networks for nitrogen dioxide and ozone and its application in Granada, a city located in Andalusia, southern Spain. The city has a population of 236,988 inhabitants, and traffic is its main source of air pollution. Sampling campaigns with passive diffusion samplers at 88 sites were carried out to obtain information on the pollution distribution in Granada. The average concentrations found for NO2 and O3 were 36.5 μg/m3 and 51.6 μg/m3, respectively. Maximum values of up to 57.1 μg/m3 NO2 were found in Granada city center and O3 reached 77.2 μg/m3 downwind from the emission source. After spatial interpolation of the obtained values with Geographical Information Systems, a selection of the best locations for the monitoring stations was made, in line with the macro- and microscale siting requirements of the European Directive 2008/50/EC on ambient air quality and cleaner air for Europe. Another sampling campaign with diffusive samplers was carried out in 2007 to determine if the locations of the air quality assessment stations were still representative for their zone. A correction was made in the control network following results of this verification campaign.  相似文献   
9.
The effects of sonication time, nitrogen, N2(g), increasing temperature, dissolved oxygen (DO) and titanium dioxide (TiO2) concentrations on the sonodegradation of polyaromatic hydrocarbons (PAHs) in petrochemical wastewaters were investigated. Sonication alone without N2(g), DO and TiO2 provided 80% maximum PAH yields at 2 5°C after 150 min. This PAH yield increased to 89–95% at 60 °C after 150 min sonication. The contribution of DO, N2(g) and TiO2 on the PAH removal was not significant compared to the control. In the presence of HCO3 ?, the degradation of hydrophobic PAH dibenz[a,h]anthracene (DahA)was suppressed in the acceleration step of the sonication. Maximum acute toxicity removal was reached by 30 min N2(g) sparging, 4 mg/L DO and by 0.1 mg/L TiO2 after 150 min sonication.  相似文献   
10.
运用HF-HClO4-H2SO4消解高纯二氧化钛,ICP-AES法测定其中的微量着色杂质铬。采用基体匹配法消除样品中钛基体的影响。该方法简便、可靠、准确,方法的精密度小于5%改为方法的精密度在0.34%~4.11%之间,结果满意。  相似文献   
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