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61.
Electrochemical recovery of hydrogen from coal acid mine drainage for the enhancement of sulphate reduction using grass cellulose as carbon source 下载免费PDF全文
Jean Mulopo 《Water and Environment Journal》2017,31(3):302-309
This paper investigates the generation of hydrogen at the cathode in an electrolytic cell treating acid mine drainage (AMD) and the effect of the generated hydrogen on the biological removal of sulphate using grass cellulose. The performance of the bioreactors was assessed by means of sulphate reduction, chemical oxygen demand (COD), and volatile fatty acid (VFA) utilization. To this end, two batch reactors, A, B were operated similarly with the exception of the addition of hydrogen. Reactor A received no hydrogen to act as a control, while reactor B received hydrogen for the experimental duration. Further experiments were conducted to investigate the feasibility of sulphide oxidation to elemental sulphur using air. The results show that during sulphide oxidation, the sulphate concentration decreased from 364 to 183 mg/L, a decrease of 50% and the concentration of sulphide decreased from 163 to 70 mg/L, a decrease of 57%. 相似文献
62.
63.
Alina-Crina Ciubotariu Lidia Benea Magda Lakatos-Varsanyi Viorel Dragan 《Electrochimica acta》2008,53(13):4557-4563
In this paper, the results on the electrochemical impedance spectroscopy and corrosion properties of electrodeposited nanostructured Al2O3-Ni composite coatings are presented. The nanocomposite coatings were obtained by codeposition of alumina nanoparticles (13 nm) with nickel during plating process. The coating thickness was 50 μm on steel support and an average of nano Al2O3 particles inside of coatings at 15 vol.% was present. The structure of the coatings was investigated by scanning electron microscopy (SEM). It has been found that the codeposition of Al2O3 particles with nickel disturbs the nickel coating's regular surface structure. The electrochemical behavior of the coatings in the corrosive solutions was investigated by polarization potentiodynamic and electrochemical impedance spectroscopy methods. As electrochemical test solutions 0.5 M sodium chloride and 0.5 M potassium sulphate were used in a three electrode open cell. The corrosion potential is shifted to more negative values for nanostructured coatings in 0.5 M sodium chloride. The polarization resistance in 0.5 M sodium chloride decreases in 24 h, but after that increases slowly. In 0.5 M potassium sulphate solution the polarization resistance decreases after 2 h and after 30 h of immersion the polarization resistance is higher than that of the beginning value. The corrosion rate calculated by polarization potentiodynamic curves obtained after 30 min from immersion in solution is smaller for nanostructured coatings in 0.5 M potassium sulphate (4.74 μm/year) and a little bit bigger in 0.5 M sodium chloride (5.03 μm/year). 相似文献
64.
65.
Zinc diffusion and extractability as affected by zinc carrier and soil chemical properties 总被引:1,自引:0,他引:1
A. S. Modaihsh 《Nutrient Cycling in Agroecosystems》1990,25(2):85-91
This work was carried out to evaluate the effect of soil chemical properties, Zn carrier and time elapsed after fertilizer application on the diffusion and extractability of Zn. A soil block technique was used to study zinc diffusion and DTPA extractability from ZnEDTA and ZnSO4 fertilizers in three soils that varied in texture, CaCO3 content, organic matter content, and pH using Zn65 tracer. ZnEDTA diffused readily in all soils, moving 20–25 mm from the fertilizer layer after three days. The rate of Zn diffusion and the extractability of Zn, however, varied among the soils and were lowest in Baha soil with the highest clay content, organic matter, and CEC despite its lower pH. The high pH and CaCO3 content in Dirab soil did not restrict the diffusion or reduce the extractability of ZnEDTA in this soil. On the other hand, the diffusion of Zn from ZnSO4 fertilizer was largely restricted in all soils and was confined to 5 mm from the fertilizer layer after 13 d. The extractability of ZnSO4 fertilizer was largely affected by soil pH and CaCO3 content and was lowest in Dirab calcareous soil. Organic matter amendment at 5% (as alfalfa) considerably reduced the diffusion and the extractability of ZnSO4 in both Dirab calcareous and Bakyria noncalcareous soils. The application of 1% (w/w) elemental S reduced soil pH and increased Zn diffusion from ZnSO4 fertilizer in Bakyria soil but had slight effect on Dirab calcareous soil. 相似文献
66.
钼冶炼烟气制酸产生的高氟废水采用电石渣-氯化钙和硫酸亚铁处理,再用浓硫酸反调pH值后排放.通过实验室试验,确定中和pH值范围为10~ 11、氯化钙用量为400 mg/L、硫酸亚铁用量为600 mg/L,沉淀时间4h.工业应用表明,出水可满足GB 8978-1996《废水综合排放标准》一级排放要求. 相似文献
67.
研究了硫酸耐尔蓝与十二烷基苯磺酸钠(SDBS)的反应,建立测定SDBS的双波长叠加紫外光度法。在pH=5.02缓冲溶液中,硫酸耐尔蓝与SDBS形成离子缔合物,在紫外区有正、负吸收峰,大正吸收波长位于304 nm,大负吸收波长位于280 nm,摩尔吸光系数分别为ε280为2.5×104L·mol-1·cm-1,ε304为2.2×104L·mol-1·cm-1,当用双波长叠加法时,ε280+304为4.7×104L·mol-1·cm-1,线性范围均为0.5~4 mg/L。研究了反应的适宜条件,用于环境水中SDBS的测定,回收率在98.9%~103.2%。 相似文献
68.
搭配上层为二折叶式,下层为推进式的双层搅拌桨,选用聚丙烯(PP)或增强聚丙烯(PPR)材质的管束冷却,代替搪瓷反应釜夹套冷却应用于硫酸铜结晶生产过程,解决了搪瓷夹套换热面积受限制问题,缩短了冷却结晶时间,提高了硫酸铜生产效率。 相似文献
69.
段威 《硫磷设计与粉体工程》2012,(5):42-45,52
针对氟硅酸钠生产中收率偏低分析其化学反应的影响因素,并采取调整生产中的盐水过量系数和母液循环回收利用等多种改进措施,实现了氟硅酸钠生产装置产品收率的较大提升,由改进前的73%提高到改进后的81%,大大的提高了磷肥副产氟资源的回收利用率. 相似文献
70.
采用平面波展开法数值计算了对二维光子晶体在TE和TM偏振态下的带隙进行了计算,给出了光子晶体中的禁带存在的理论依据,选择二维三角晶格光子晶体(GaAs)作为基底,在空气孔内填充浓度(质量百分浓度)为一定的待测溶液硫酸铜材料,通过计算得到了温度为298K情况下介电常数在71.917-62.530变化时,待测浓度的对应关系,并由此得到液体填充的光子晶体在不同偏振模式下光子禁带结构.结果表明,以硫酸铜的水溶液作为空气圆孔中的介质材料,当溶液质量百分浓度不同时光子带隙(PBG)发生变化。这对溶液浓度检测应用方面有一定的指导作用。 相似文献