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151.
介绍了改良MEA脱碳技术的基本原理、工艺特点以及在工业中的应用情况,实践表明,改良MEA提高了溶液的吸收能力,降低了再生热耗,解决了MEA易降解损耗等问题。 相似文献
152.
用活性炭填充弹性高发泡乙烯/醋酸乙烯共聚物颗粒制备新型悬浮填料,在悬浮填料移动床工艺中为微生物提供附着生长的载体。载体具有通孔结构,从表面到内部形成不同溶解氧梯度,在反应器内发生同时硝化反硝化反应(SND)。研究表明,当双螺杆挤出温度为185℃、交联剂过氧化二异丙苯为1%(质量分数,下同)、发泡剂偶氮二甲酰氨为1.5%、活性炭为18%时,填料密度和空隙率分别达到0.85g/mL和60%。在复合式生物反应器中处理模拟生活污水,发生SND的工艺条件为:溶解氧(DO)为2.0~2.2mg/L,碳氮比(COD/YH4^+-N,简写为C/N)为30,水力停留时间为5h。 相似文献
153.
A lab-scale anaerobic-anoxic-oxic (A^2O) process used to treat a synthetic brewage wastewater was investigated. The objectives of the study were to identify the existence of denitrifying phosphorus removing bacteria (DPB), evaluate the contribution of DPB to biological nutrient removal and enhance the denitrifying phosphorus removal in A^2O bioreactors. Sludge analysis confirmed that the average anoxic P uptake accounted for approximately 70% the total amount of P uptake, and the ratio of anoxic P uptake rate to aerobic P uptake rate was 69%. In addition, nitrate concentration in the anoxic phase and different organic substrate introduced into the anaerobic phase had significant effect on the anoxic P uptake. Compared with conventional A^2O processes, good removal efficiencies of COD, phosphorus, ammonia and total nitrogen (92.3%, 95.5%, 96% and 79.5%, respectively) could be achieved in the anoxic P uptake system, and aeration energy consumption was saved 25%. By controlling the nitrate recirculation flow in the anoxic zone, anoxic P uptake could be enhanced, which solved the competition for organic substrates among poly-P organisms and denitrifiers successfully under the COD limiting conditions. Therefore, in wastewater treatment plants the control system should be applied according to the practical situation to optimize the operation. 相似文献
154.
155.
介绍了焦炉湿式与干式推焦地面除尘系统的流程,对两者在运行特点、运行能耗、运行维护、除尘效果等方面进行了比较,指出两种除尘系统的优劣,认为湿式除尘系统由于采用了新型湿式高效净化装置,在焦炉地面除尘上更具有优势。 相似文献
156.
草酸是废水中多种有机物氧化降解的中间产物,与臭氧反应速率很低,难以直接氧化去除。本研究通过热解法煅烧不同摩尔比例的三聚氰胺与醋酸锰(Ⅲ)二水合物,制备出不同负载量的载锰氮化碳催化剂,并研究了不同条件下载锰氮化碳催化臭氧法对草酸的降解效果,考察三聚氰胺与醋酸锰摩尔比、催化剂投加量、p H值、臭氧浓度等因素以及叔丁醇对草酸去除效果的影响。实验结果表明:相对于单独臭氧氧化而言,载锰氮化碳催化臭氧法可以极大的提高草酸的去除率,在投加0.15 g/L三聚氰胺与醋酸锰20∶1的催化剂后,草酸在60 min的TOC去除率可达到89.1%。叔丁醇加入对草酸的去除率影响较小,表明·OH在载锰氮化碳催化氧化草酸的过程中起作用但不是唯一因素。 相似文献
157.
The rates of absorption of CO2 into water and 0.1 kmol/m3 aqueous solutions of MEA, DEA and AMP were measured in a stirred cell with a flat gas-liquid interface in the presence of fine activated carbon particles. Experiments showed that the rates of absorption increased significantly with increases in the loading of activated carbon up to about 6 kg/m3 and thereafter remained constant. 相似文献
158.
The purpose of this study is to conduct a concurrent product and process parameters determination for further cost reduction and quality enhancement. The process design-related parameters, such as process mean, process tolerance and product design-related parameters, such as product tolerance, are considered simultaneously in the proposed approach. To reflect the response from these three key controllable characteristics: process mean, process tolerance and product tolerance, the key measurement score, which is the sum of the mean cost, tolerance cost, quality loss and failure cost, is used to evaluate the present model. Two examples are provided for demonstrating the application of single and multiple quality characteristics. 相似文献
159.
The electrochemical oxidation of 2-naphthol has been studied by galvanostatic electrolysis, using a range of electrode materials such as lead dioxide, boron-doped diamond (BDD) and Ti-Ru-Sn ternary oxide anodes. The influence of some operating parameters, such as current density, flow-rate and chloride concentration on naphthol oxidation has been investigated in order to find the optimum experimental conditions. Measurements of chemical oxygen demand, HPLC and total organic carbon have been used to follow the oxidation. The experimental data indicate that on PbO2 and BDD, naphthol oxidation takes place by reaction with electrogenerated hydroxyl radicals and is favoured by low current density and high flow-rate. On the contrary, on a Ti-Ru-Sn ternary oxide the mineralisation of naphthol occurs only in the presence of chloride ions that act as redox mediators and COD removal is affected by chloride concentration and is not significantly influenced by the current density and mass-transfer coefficient. From a comparison of the results of the three electrodes it has been found that boron-doped diamond gives a faster oxidation rate and better current efficiency. 相似文献
160.
通过改变电流密度、通电时间、沉淀时间等因素,采用电凝聚法对微污染水中的细菌、浊度、CODMn的去除进行了试验研究。得出电凝聚通过电解氧化、凝聚和气浮联合作用,对微污染水中的浊度、细菌能有效地去除,同时对CODMn具有很强的降解作用。 相似文献