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731.
采用穆斯堡尔谱学方法分析煤粉的微波脱硫效果。结果表明微波辐照后煤粉样对应的同质异能移IS和谱面积A都较未辐照的减小 ,并出现磁超精细场 ,说明微波辐照后煤粉中的黄铁矿开始向磁黄铁矿转化。通过计算 ,在给定的微波辐照条件下 ,黄铁矿转化为磁黄铁矿的转化率为 2 4 7% 相似文献
732.
通过对中国北方城市SO2污染的季节性特点进行分析发现,减少采暖燃煤SO2排放,解决采暖期SO2污染,是SO2年日均值达标的关键。而改变采暖期能源结构和采暖方式,将传统燃煤取暖改为清洁能源取暖,提高电厂排放SO2占SO2排放总量中的比例,可以解决大多数北方城市采暖期SO2难以达标的问题。同时,通过电厂脱硫设施建设可有效控制SO2排放总量。 相似文献
733.
734.
735.
目的研究元素硫对825合金在高温高压含CO2/H2S环境中腐蚀行为的影响,为评价825合金在高温高压含CO2/H2S和元素硫环境中的适应性提供依据。方法将825合金分别置于含元素硫和不含元素硫的模拟气田环境中,进行高温高压含硫实验。采用失重法、高温高压电化学法、扫描电镜和能谱测试方法对825合金的均匀腐蚀、局部腐蚀、电化学腐蚀、微观形貌和化学组成进行表征,揭示元素硫对825合金在高温高压含H2S和CO2环境中腐蚀行为的影响规律。结果在不含元素硫的环境中,825合金的均匀腐蚀速率仅为0.0217 mm/a,无局部腐蚀现象产生,也没有检测到明显的点蚀噪声信号;在含元素硫的环境中,825合金的均匀腐蚀速率高达0.469 mm/a,具有明显的局部腐蚀特征,且点蚀噪声信号显著,与光学照片观察结果一致。结论825合金在高温高压含元素硫和氯离子环境中容易发生局部腐蚀,这主要是由于元素硫在水溶液中发生水解反应,在局部区域生成了H2S和H2SO4,在高温和氯离子的耦合作用下,显著地加剧了825合金的腐蚀,腐蚀产物以氧化物和硫化物为主。 相似文献
736.
采用溶胶凝胶法制备4%Ag/Al2O3、4%Ag/10%TiO2-Al2O3催化剂.利用N2物理吸附、氮氧化物/二氧化硫程序升温脱附(NOx/SO2-TPD)以及普通/原位漫反射傅里叶变换红外光谱(FT-IR/DRIFTs)对催化剂进行表征,并探讨催化剂在含硫气氛前后选择性还原NOx活性的变化及中毒机理.结果表明在4%Ag/Al2O3催化剂中掺杂10%TiO2能提高催化剂的中低温活性以及在400℃下抗SO2中毒的能力.TiO2引入后可促进甲酸盐物种的形成从而有利于低温反应的进行;SO2与NO在同一活性位上出现的竞争吸附以及活性组分Ag的硫酸化是4%Ag/Al2O3催化剂失活的重要原因;TiO2的加入能促进NO在催化剂表面的吸附并能减弱其对SO2的吸附,同时能有效抑制活性组分Ag的硫酸化,从而提高催化剂的抗硫性. 相似文献
737.
Odor emission characteristics in rendering plant was studied by measuring 14 kinds of odorants in the emission gases from main processes: cooking of raw bone, concentrating of glue, refining of fat, and drying of bone. The odor from cooker had higher concentration of all odorous components compared with the other processes. From any process except the drying one, there were detected sulfur‐containing odorants in very high concentration. Of the odorants, concentrations of hydrogen sulfide and methyl mercaptan were higher. The odor from drying bed had comparatively low concentration of sulfur‐containing odorants, and higher concentration of ammonia and trimethylamine were detected. Lower fatty acids were detected from all processes though the concentrations were low. In the odorous gases taken at both the emission source and borderline side, high correlations were recognized between organoleptic test value and concentrations of measured odorants. 相似文献
738.
C. M. Tu 《Journal of environmental science and health. Part. B》2013,48(6):1201-1214
Abstract With the exception of EPTC, herbicide treatments showed inhibitory effects on bacterial colony counts in a sandy loam soil for the first week. Monolinuron and simazine were stimulatory to the growth of fungi in the organic soil after 2 wk. None of the herbicide treatments affected nitrification during the first week of incubation. Except the treatment of EPTC in organic soil, all herbicides inhibited nitrification after 2 wk in both soils. All herbicide treatments stimulated SO4 formation during the 8‐wk period in the sandy loam soil. Simazine and tridiphane also stimulated sulfur oxidation after 4 wk in an organic soil. With the exception of EPTC and nitrapyrin, no significant inhibitory effect on the amount of biomass‐C was observed in the organic soil. A stimulatory effect on denitrification was observed with EPTC for 2 wk and monolinuron for 1 wk in the sandy loam soil and with simazine and tridiphane after 2 wk in the organic soil. It is apparent that the indigenous soil microorganisms can tolerate the effects of the chemicals for control of soil weeds. 相似文献
739.
740.
Xue-Yan Liu Hua-Yun Xiao Cong-Qiang Liu Hong-Wei Xiao Yan-Li Wang 《Environmental pollution (Barking, Essex : 1987)》2009,157(7):2066-2071
The application of geochemical signals in mosses is more and more popular to investigate the deposition of atmospheric pollutants, but it is unclear whether records of atmospheric sulfur in mosses differ between their diverse habitats. This study aimed to investigate the influence of growing condition on tissue sulfur and δ34S of Haplocladium microphyllum. Epilithic and terricolous mosses in open fields, mosses under different canopy conditions were considered. We found that tissue sulfur and δ34S of mosses under different habitats were not consistent and could not be compared for atmospheric sulfur research with each other even collected at the same site, moss sulfur and δ34S records would be distorted by subsoil and upper canopies in different degrees, which possibly mislead the interpretation of atmospheric sulfur level and sources. Consequently, mosses on open rocks can be used reliably to assess atmospheric-derived sulfur in view of their identical sulfur and δ34S evidences. 相似文献