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91.
As an attempt to recycle iron scraps, a new method is proposed to produce stainless steel clad plate by hot rolling. Iron scraps (Q195) were cold pressed into stainless steel pipe (304), and were subsequently hot rolled to produce composite clad plates at 1250 °C. Experiments showed that the iron scraps could be compressed into solid steel and joined well with the outer stainless steel surface using the proposed method. The shear strength of the bimetallic interface formed is about 273 MPa after seven pass rolling. The clad plates produced show good bending ductility. Element diffusion occurred at the interface during the hot rolling processes. The peak hardness appears in the vicinity of the interface due to the severe plastic deformation under high temperature and pressure during the rolling processes.  相似文献   
92.
姚方 《煤化工》2008,36(2):60-62
介绍了造气工艺流程中的煤气炉洗涤循环水减排技术和吹风气回收节能技术。根据不同絮凝剂应用试验,提出了企业应根据不同工艺特点采用相应的悬浮物去除技术方案,应用微涡流塔板澄清器从本质上可提高悬浮物的控制水平和降低悬浮物含量;根据不同工艺流程对硫化物含量的控制效果的差异性,提出对应改造方案。并介绍了吹风气回收装置的工艺路线改进方案和改造后运行中需采取的措施,改造实施后,可获得较好的经济效益。  相似文献   
93.
孙亚明 《云南化工》2008,35(2):36-40
随着塑料使用量的大增,废旧塑料己造成了严重的环境污染,同时又蕴含着重要的再生资源。石油和煤不可再生,资源紧缺,从节约地球资源和保护地球环境的角度考虑,目前各国对废旧塑料回收都非常重视,投入大量人力、物力乃至立法,开发各种废旧塑料回收利用的关键技术.废旧塑料回收方法主要有熔融再生,热裂解,能量回收,回收化工原料及其它。主要用途以及技术研究方向有制造燃油、生产防水抗冻胶、制取芳香族化合物、制备多功能树脂胶、防火装饰板、再生颗粒、生产克漏王、制备环保漆、沥青改性材料、流化床气化。相应的设备研制还未跟上。  相似文献   
94.
For the first time, the coupling of fast transient kinetic switching and the use of an isotopically labelled reactant (15NO) has allowed detailed analysis of the evolution of all the products and reactants involved in the regeneration of a NOx storage reduction (NSR) material. Using realistic regeneration times (ca. 1 s) for Pt, Rh and Pt/Rh-containing Ba/Al2O3 catalysts we have revealed an unexpected double peak in the evolution of nitrogen. The first peak occurred immediately on switching from lean to rich conditions, while the second peak started at the point at which the gases switched from rich to lean. The first evolution of nitrogen occurs as a result of the fast reaction between H2 and/or CO and NO on reduced Rh and/or Pt sites. The second N2 peak which occurs upon removal of the rich phase can be explained by reaction of stored ammonia with stored NOx, gas phase NOx or O2. The ammonia can be formed either by hydrolysis of isocyanates or by direct reaction of NO and H2.

The study highlights the importance of the relative rates of regeneration and storage in determining the overall performance of the catalysts. The performance of the monometallic 1.1%Rh/Ba/Al2O3 catalyst at 250 and 350 °C was found to be dependent on the rate of NOx storage, since the rate of regeneration was sufficient to remove the NOx stored in the lean phase. In contrast, for the monometallic 1.6%Pt/Ba/Al2O3 catalyst at 250 °C, the rate of regeneration was the determining factor with the result that the amount of NOx stored on the catalyst deteriorated from cycle to cycle until the amount of NOx stored in the lean phase matched the NOx reduced in the rich phase. On the basis of the ratio of exposed metal surface atoms to total Ba content, the monometallic 1.6%Pt/Ba/Al2O3 catalyst outperformed the Rh-containing catalysts at 250 and 350 °C even when CO was used as a reductant.  相似文献   

95.
In the steam gasification of biomass, the additive effect of noble metals such as Pt, Pd, Rh and Ru to the Ni/CeO2/Al2O3 catalyst was investigated. Among these noble metals, the addition of Pt was most effective even when the loading amount of added Pt was as small as 0.01 wt.%. In addition, the catalyst characterization suggests the formation of the Pt–Ni alloy over the Pt/Ni/CeO2/Al2O3.  相似文献   
96.
研究了影响夜光开关辉度的因素。结果表明,开关的发光亮度(辉度)随夜光颜料的含量、夜光部件厚度的增大而增加,伴随着制件的着色,夜光部件的亮度会降低;介绍了夜光开关的加工方法及加工中应注意的问题;探讨了夜光开关材料回收时存在的问题并提出了相应的解决办法。  相似文献   
97.
电镀污泥中铜、镍、铬、锌的回收利用研究   总被引:3,自引:0,他引:3  
研究电镀污泥中铜、镍、铬、锌的回收工艺流程,确定最佳的工艺条件。结果表明,电镀污泥中铜、镍、铬、锌的浸出率分别达到97.8%、98.6%、94.8%和99.0%,并可循环回收;废渣无害化,可按一般工业固废处置;生产过程闭路循环,无任何排放,实现清洁生产.  相似文献   
98.
氯乙烯生产过程中"三废"的处理   总被引:1,自引:0,他引:1  
介绍了氯乙烯生产过程中触媒废气、氯乙烯废水、酸性废水、碱性废水、精馏尾气及高沸物的处理方法.经过处理,减少了废水和废气的排放量,回收了氯乙烯,既达到了清洁生产的目的又降低了物料消耗.  相似文献   
99.
Eutrophication caused by the excessive supply of phosphate to water bodies has been considered as one of the most important environmental problems. In this study, the powder of zirconium mesostructure (ZM), which was prepared with the template of surfactant, was immobilized in calcium alginate for practical application and the resulting material was tested to evaluate the phosphate removal efficiency. Sorption isotherms and kinetic parameters were obtained by using the entrapped ZM beads with 30 to 60% of ZM. The maximum sorption capacity increased with the higher ZM content. Q max in Langmuir isotherm was 51.74 mg/g for 60% of ZM with 7 mm of size. The smaller the particle size of the ZM beads, the faster the rate of phosphate removal, because the phosphate ions had less distance to reach the internal pores of the immobilized ZM beads. Chemical and electrochemical regeneration techniques were compared. Phosphates adsorbed on the ZM beads were effectively desorbed with NaCl, NaOH, and Na2SO4 solutions. An electrochemical regeneration system consisting of an anion exchange membrane between two platinum-coated titanium electrodes was successfully used to desorb and regenerate the phosphate-saturated ZM beads. Complete regeneration was reached under optimal experimental conditions. Chemical and electrochemical regeneration proved the reusability of the bead form of the entrapped ZM, and will enhance the economical performance of the phosphate treatment process.  相似文献   
100.
本文利用自制的萃取剂A,对粗制硫酸铝溶液〔1〕中的萃取除铁效率进行了实验研究,并探讨了萃取剂的再生方法和适宜条件。实验结果表明:使用萃取剂A,对粗制硫酸铝溶液萃取二次,可使2800ppm 的铁减少到30ppm 以下,达到无铁硫酸铝的要求,而铝几乎不损失。对使用过的萃取剂以2.7% 的硫酸溶液反萃取二至三次后,再通过水洗,碱洗,水洗,即实现再生,可以循环使用。  相似文献   
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