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11.
The photocatalytic decomposition of ethylene glycol and propylene glycol was investigated by using UV-illuminated TiO2 and metal-loaded TiO2 catalysts. The effects of pH, initial concentration, and wavelength of light on the decomposition rate of the glycols were
explored. Platinum-and palladium-loaded TiO2 catalysts enhanced the rates of photodecomposition compared to unloaded TiO2. The glycols were oxidized primarily to carbon dioxide and water. Formaldehyde was found to be an important reaction intermediate.
A detailed chemical reaction mechanism for the destruction of ethylene glycol and propylene glycol in water via free radical
pathway and trapped hole reactions at the particle surface is proposed. 相似文献
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13.
J. Klier C. J. Tucker T. H. Kalantar D. P. Green 《Advanced materials (Deerfield Beach, Fla.)》2000,12(23):1751-1757
Microemulsions are thermodynamically stable, fluid, optically clear dispersions of two immiscible liquids. Recent interest in microemulsion systems has resulted from their utility in a broad range of applications including enhanced oil recovery, consumer and pharmaceutical formulations, nanoparticle synthesis, and chemical reaction media. However, the high levels typically required to ensure complete microemulsification and formulation stability often result in unacceptably high residue, contaminant levels, and formulation cost. One way to reduce surfactant requirements in microemulsion systems is through the use of efficient surfactants and interfacially active cosurfactants. We have explored and developed microemulsion systems based on efficient anionic surfactants and glycol ether cosurfactants that are stable to temperature and compositional changes and yet employ low levels of non‐volatile surfactants. These microemulsion systems are finding utility in a range of applications, including consumer and industrial cleaning formulations, chemical reaction media, polymerization, and active ingredient delivery. 相似文献
14.
P.D. Francis 《臭氧:科学与工程》1987,9(4):369-390
Organic contaminants dissolved in deionized pretreated and raw mains water were reacted with ultraviolet light and ozone. Ozone first was used for partial oxidation followed by ozone combined with ultraviolet radiation to produce total oxidation. The reduction of TOC level and direct oxidation of halogenated compounds were measured throughout the treatment process. The rate of TOC reduction was compared for ozone injected upstream and inside the reactor. 相似文献
15.
乙二醇装置在多年的生产过程中逐渐暴露出了许多腐蚀问题,虽然目前已有许多企业关注并加强了乙二醇装置的腐蚀控制,但总体上讲腐蚀问题并未得到充分重视。文章简要介绍了目前国内乙二醇装置的生产工艺原理,重点对乙二醇装置的腐蚀现状进行了总结分析,从加强工艺操作、材质升级、表面处理、腐蚀监测等方面对防腐对策进行了介绍。 相似文献
16.
We constructed a fuel‐flexible fuel cell consisting of an alkaline anion exchange membrane, palladium anode, and platinum cathode. When an alcohol fuel was used with potassium hydroxide added to the fuel stream and oxygen was the oxidant, the following maximum power densities were achieved at 60 °C: ethanol (128 mW cm−2), 1‐propanol (101 mW cm−2), 2‐propanol (40 mW cm−2), ethylene glycol (117 mW cm−2), glycerol (78 mW cm−2), and propylene glycol (75 mW cm−2). We also observed a maximum power density of 302 mW cm−2 when potassium formate was used as the fuel under the same conditions. However, when potassium hydroxide was removed from the fuel stream, the maximum power density with ethanol decreased to 9 mW cm−2 (using oxygen as oxidant), while with formate it only decreased to 120 mW cm−2 (using air as the oxidant). Variations in the performance of each fuel are discussed. This fuel‐flexible fuel cell configuration is promising for a number of alcohol fuels. It is especially promising with potassium formate, since it does not require hydroxide added to the fuel stream for efficient operation. 相似文献
17.
二甘醇或乙二醇连续催化合成1,4-二氧六环 总被引:1,自引:0,他引:1
采用连续法合成1,4 二氧六环。以二甘醇为原料,温度240℃,催化剂初始浓度:硅钼酸3%,或硫酸铁3%,或硅钨酸银2%;连续补加浓度:硅钼酸1%,硫酸铁1%,硅钨酸银05%;以乙二醇为原料,温度190℃,催化剂初始浓度:硅钼酸4%,或硫酸铁35%,或硅钨酸银2%;补加浓度:硅钼酸15%,硫酸铁15%,硅钨酸银1%;控制塔顶温度为95~105℃,反应速度快,产率较高。 相似文献
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The effects of organic additives on the electrochemical and morphological deposit changes from acid tin methanesulfonate solutions are presented. In the absence of additives, tin deposition is diffusion-controlled with concomitant hydrogen gas evolution and the tin deposits are rough. Addition of polyethylene glycol suppresses hydrogen gas evolution yet has little effect on the mechanism of stannous reduction and the deposit structures. Polypropylene glycol enhances stannous reduction and produces a slightly smoother tin coating. The addition of phenolphthalein to solutions already containing the glycol additives results in a kinetically-controlled tin reduction process and a smooth matte tin deposit. 相似文献
20.
在常压、313-413K下,采用NDJ-1旋转式黏度计,测定了含NY2催化剂的乙二醇和二甘醇的黏度.采用黏度Andrade关系式,将黏度数据与NY2催化剂质量分数和温度进行关联,得到经验关系式.结果表明,由经验方程计算值与实验结果基本相符,为催化水合制乙二醇的反应器设计和优化分离设备提供必要的基础数据. 相似文献