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81.
城市生活垃圾焚烧烟气的新式净化工艺处理效果 总被引:6,自引:0,他引:6
二恶英类毒物是目前已知最有害的环境污染物之一,而迄今为止,90%的二恶英类毒物都来源于垃圾焚烧.作为垃圾焚烧烟气中的重点污染物,在确定垃圾焚烧烟气净化工艺时,应重点考虑对该种污染物的去除.传统的半干法净化工艺普遍对二恶英类污染物的处理效果不佳,而利用半干法净化法 活性炭注射法 袋式除尘器法相结合的新工艺对垃圾焚烧烟气进行处理,经实用证明,达到了理想的净化效果. 相似文献
82.
通过对ZG32Cr06铸钢粗晶成因的分析及消除粗晶的工艺性能试验,探讨了粗晶导致铸件断裂的机理。试验证明,由于浇铸温度过高,水爆清砂时开箱过早而产生的粗晶可以用热处理方法消除,同时提出了铸件在浇铸时防止粗晶的措施。 相似文献
83.
84.
The current aqueous cleaning step in the surface preparation of aluminum nitride (AlN) prior to metallization causes performance and reliability issues for the substrates used for microelectronic packaging due to surface reactions. These issues limit the use of AlN and its replacing of BeO, an environmentally hazardous material currently used. The aim of this investigation was to determine the effects of different solutions on the surface of AlN substrates under varying conditions at times up to 2419.2 ks (28 days). Concentration of the solutions, temperature, and immersion time were varied for the AlN samples in the solutions. Both elevated temperatures (50°C and 90°C) and low temperatures (5°C) were investigated.
Four general types of behavior were observed: minor changes in average surface roughness and microstructure, linear change in average surface roughness and pitted grains, nonlinear change in average surface roughness and product formation on AlN surface, and miscellaneous change in average surface roughness with surface product formation.
The surface roughening kinetics were very complex due to changes in both the reaction product morphology and reaction mechanism with temperature, solvent, and pH for a specific solvent. Minor changes in average surface roughness and microstructure were observed for HCl pH = 5, H2 SO4 pH = 5, NaOH pH = 8, NaOH pH = 10, NaOH pH = 12, deionized water and Alfred tap water at 5°C, HCl pH = 3 and oleic acid at 50°C and citric acid and oleic acid at 90°C. Linear changes in average surface roughness and pitted grains were observed for HCl pH = 2 and H2SO4 pH = 3 at 50°C and HCl pH = 2, H2SO4 pH = 3, and deionized water at 90°C. Non-linear change in average surface roughness and product formation on AlN surface was observed for HCl pH = 5, NaOH pH = 8 and Alfred tap water at 50°C and HCl pH = 5 and H2SO4 pH = 2 at 90°C. Miscellaneous changes in average surface roughness with surface product formation were observed for H2SO4 pH = 2, H2SO4 pH = 5, NaOH pH = 10, NaOH pH = 12, citric acid, Micro-90 and deionized water at 50°C and HCl pH = 3, H2SO4 pH = 5, NaOH pH = 8, NaOH pH = 10, NaOH pH = 12, Micro-90 and Alfred tap water at 90°C. 相似文献
Four general types of behavior were observed: minor changes in average surface roughness and microstructure, linear change in average surface roughness and pitted grains, nonlinear change in average surface roughness and product formation on AlN surface, and miscellaneous change in average surface roughness with surface product formation.
The surface roughening kinetics were very complex due to changes in both the reaction product morphology and reaction mechanism with temperature, solvent, and pH for a specific solvent. Minor changes in average surface roughness and microstructure were observed for HCl pH = 5, H2 SO4 pH = 5, NaOH pH = 8, NaOH pH = 10, NaOH pH = 12, deionized water and Alfred tap water at 5°C, HCl pH = 3 and oleic acid at 50°C and citric acid and oleic acid at 90°C. Linear changes in average surface roughness and pitted grains were observed for HCl pH = 2 and H2SO4 pH = 3 at 50°C and HCl pH = 2, H2SO4 pH = 3, and deionized water at 90°C. Non-linear change in average surface roughness and product formation on AlN surface was observed for HCl pH = 5, NaOH pH = 8 and Alfred tap water at 50°C and HCl pH = 5 and H2SO4 pH = 2 at 90°C. Miscellaneous changes in average surface roughness with surface product formation were observed for H2SO4 pH = 2, H2SO4 pH = 5, NaOH pH = 10, NaOH pH = 12, citric acid, Micro-90 and deionized water at 50°C and HCl pH = 3, H2SO4 pH = 5, NaOH pH = 8, NaOH pH = 10, NaOH pH = 12, Micro-90 and Alfred tap water at 90°C. 相似文献
85.
阐述了整杆式甘蔗收获机械非直线排列剥叶元件疲劳分析的总体思路.利用计算机仿真分析的方法分析了剥叶元件装夹参数及其注塑加工过程中产生的缺陷对元件寿命的影响,提出了不同工况剥叶元件疲劳分析的有限元计算模型.通过仿真分析,方便、快捷地得出剥叶元件疲劳寿命预估值,并用试验证明了其有效性. 相似文献
86.
TiO2纳米光催化杀菌技术及其在空调系统中的应用 总被引:3,自引:0,他引:3
论述了TiO2纳米光催化技术降解有机污染物的机理及在空气净化与杀菌技术方面的应用,给出了将TiO2纳米光催化与传统空气净化技术结合应用于空调系统中的方法,指出了应用方面存在的问题及发展方向。 相似文献
87.
As the demand for large capacity storage drives has increased, the flying height of near-field recording (NFR) sliders becomes
as small as 100 nm for super high storage density. Accordingly contamination problems have been a concern of information storage
industry because it may cause a serious damage to solid immersion lens (SIL) of optical flying head. Sub-micro contaminants
in air bearing of the NFR slider may affect the flyability and stability of the optical slider. In addition, the cleaning
of small particles becomes more difficult as the contaminant particle size decreases because the adhesion force increases
very much as the particle size decreases. Recently developed high-frequency ultrasonic (megasonic) cleaning technique have
made it possible to remove sub-micron particles less than 100 nm without surface erosion and many remarkable results have
been reported. In this paper, the megasonic technique is applied and tested for the cleaning of the flying head of NFR drive.
1 MHz ultrasound with maximum 100 W was used to remove polystyrene latex (PSL) particles and alumina particles deposited on
the surface of the slider. Effective cleaning performance was observed without any damages on the slider surface using optical
microscope and AFM at different ultrasonic energy levels and cleaning times.
Received: 20 June 2002 / Accepted: 9 September 2002 相似文献
88.
介绍一种用于电力系统清扫绝缘子表面污垢的风力清扫环,它由一个绝缘环和风力推动碗、毛刷环、刮板等组成,利用风力使清扫环在绝缘子上旋转,扫除和刮去绝缘子表面上的污垢,使绝缘子保持清洁,有利于防止污闪事故的发生。对比试验和实际挂网运行结果表明.这是一种防止污闪的有效方案。 相似文献
89.
针对磺化反应器的垢样,通过对酸浓度与腐蚀速率关系的研究,给磺化反应器特殊材质实施化学 清洗提供了必要的依据. 相似文献
90.
黄台电厂7号炉在第三次大修中进行了投产后的首次化学清洗,清洗方法采用了盐酸加硫脲一步除铜清洗,复合磷酸盐淋洗、钝化的工艺。清洗结果是成功的,为今后机组的安全经济运行奠定了基础;同时我们也总结了经验,吸取了教训。本文着重对这次酸洗中存在的问题做了简要的分析,提出了几点建议。 相似文献