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21.
22.
高炉风口表面处理技术 总被引:1,自引:0,他引:1
介绍近代高炉风口采取等离子喷涂、各种金属渗镀和堆焊高温耐磨合金3种方法进行表面处理的情况。我国中小高炉多趋向发展多元金属渗镀,前苏联和日本风口经堆焊后抗磨性能有明显改善,采用上述3种处理后风口寿命均有数倍的提高。 相似文献
23.
古代刀剑的外观处理技术 总被引:1,自引:0,他引:1
古代刀剑的表面处理方法有:硫化处理;铬盐氧化;错金;镶嵌;髹;失蜡和包金等,用以增进功能,装饰外表,达到保护防腐蚀的效果. 相似文献
24.
25.
详细介绍了2000m^3高压天然气球罐工程的制造、安装过程,并指出每个环节的控制要点。球罐投入运行后,工作状况良好。 相似文献
26.
Preparation of zeolitic adsorbents from waste coal fly ash 总被引:1,自引:0,他引:1
Power plants burning coal generate a large amount of fly ash as waste matter. The objective of this study is to produce zeolitic
adsorbents that possesses high adsorptive capacity for toxic cations. The sample was first pretreated with a High Intensity
Magnetic Separator for the removal of iron and magnetic materials (mainly Fe2O3 and TiO2). The zeolitic adsorbents were prepared under the various conditions of NaOH concentration (1–5 N), reaction time from 3
to 96 hours and at the various temperatures of 60, 80 and 100°C. The results of the experiment showed that the coal fly ash
should be synthesized with 4 N NaOH for 48 hours at 100°C in order to have good adsorptive capacity. The zeolitic adsorbents
showed higher cation exchange capacity values than the natural zeolite in removing NH
4
+
, Pb2+, Ca2+and Cd2+ions. 相似文献
27.
28.
H. van Leeuwen 《臭氧:科学与工程》1988,10(3):291-307
Poor sludge settleability is a problem encountered in many activated sludge wastewater treatment plants. This study was aimed at combatting the unwanted biological growths at the root of this phenomenon with ozone. Ozone dosed directly into the aeration basins of small activated sludge pilot plants treating both domestic and synthetic fuel wastewaters led to a substantial reduction of the bulking problem even at dosages as low as 6 to 10 mg/L. Ozone did not interfere in the delicate nutrient removal processes and significantly enhanced effluent quality. 相似文献
29.
Ozone has been used for a number of years in water treatment for viricidal and bactericidal action, as well as for its oxidizing properties. Energy consumption during its use depends on the performance of the ozone generators, but also on the ozone transfer efficiency from the gas phase to the liquid phase. Therefore, it is important to use a contactor with a high transfer efficiency.A new ozonation reactor has been developed: the Deep U-Tube (DUT). This reactor works under pressure, which increases the saturation concentration of ozone at equilibrium (C ). and creates a great turbulence, which breaks the gas bubbles and increases the interfacial area of exchange. Further, this new contactor has a piston hydraulic behavior in the liquid phase, which leads to a very great efficiency and to a better reduction for all reaction kinetics. 相似文献
30.
The ozonation of aniline and anilinium ion in aqueous solution is investigated by determining the product distributions at different degrees of ozonation. Results indicate that anilinium ion, although less reactive than aniline, still has a remarkable reactivity towards ozone. The high anilinium ion reactivity and the observed product distributions are explained by assuming a radical mechanism for anilinium ion ozonation, whereas the behavior of aniline appears to be regulated mainly by the electrophilic ozonolysis mechanism. 相似文献