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971.
针对硫化氢气体的特点,研制了在泄漏事故中用于清除硫化氢气体的硫化氢捕消剂;开展了密闭空间和开放空间硫化氢清除应用试验,结果表明,硫化氢捕消剂能够有效地清除泄漏在空气中的硫化氢气体。 相似文献
972.
Juan Qin Chuanmeng Yang Chong Cui Jiantao Huang Ahmad Hussain Hailong Ma 《环境科学学报(英文版)》2016,28(9):91-99
Lime mud is a kind of solid waste in the papermaking industry, which has been a source of serious environmental pollution. Ceramsites containing anorthite and gehlenite were prepared from lime mud and fly ash through the solid state reaction method at 1050°C. The objective of this study was to explore the efficiency of Ca2 + and OH− release and assess the phosphorus and copper ion removal performance of the ceramsites via batch experiments, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that Ca2 + and OH− were released from the ceramsites due to the dissolution of anorthite, gehlenite and available lime. It is also concluded that gehlenite had stronger capacity for Ca2 + and OH− release compared with anorthite. The Ca2 + release could be fit well by the Avrami kinetic model. Increases of porosity, dosage and temperature were associated with increases in the concentrations of Ca2 + and OH− released. Under different conditions, the ceramsites could maintain aqueous solutions in alkaline conditions (pH = 9.3–10.9) and the release of Ca2 + was not affected. The removal rates of phosphorus and copper ions were as high as 96.88% and 96.81%, respectively. The final pH values of both phosphorus and copper ions solutions changed slightly. The reuse of lime mud in the form of ceramsites is an effective strategy. 相似文献
973.
Identifying the major fluorescent components responsible for ultrafiltration membrane fouling in different water sources 总被引:1,自引:0,他引:1
Three-dimensional fluorescence excitation–emission matrix(EEM) coupled with parallel factor analysis(PARAFAC) was performed for a total of 18 water samples taken from three water sources(two lakes and one wastewater treatment plant(WWTP) secondary effluent),with the purpose of identifying the major ultrafiltration(UF) membrane foulants in different water sources. Three fluorescent components(C1, C2 and C3) were identified,which represented terrestrially derived humic-like substances(C1), microbially derived humic-like substances(C2), and protein-like substances(C3). The correlations between the different fluorescent components and UF membrane fouling were analyzed. It was shown that for the WWTP secondary effluent, all three components(C1, C2 and C3) made a considerable contribution to the irreversible and total fouling of the UF membrane.However, for the two lakes, only the C3 exhibited a strong correlation with membrane fouling, indicating that the protein-like substances were the major membrane foulants in the lake waters. Significant attachment of C1, C2 and C3 to the UF membrane was also confirmed by mass balance analyses for the WWTP secondary effluent; while the attachment of C1 and C2 was shown to be negligible for the two lakes. The results may provide basic formation for developing suitable fouling control strategies for sustainable UF processes. 相似文献
974.
975.
小波分析在PM10浓度时间序列分析中的应用 总被引:1,自引:0,他引:1
以西安市PM10日平均浓度时间序列为例,根据小波分析的基本原理,应用小波分解和重构对PM10浓度时间序列的变化进行了分析,得到PM10的年变化趋势和突变特征。研究结果表明,用小波分析应用于大气污染物浓度时间序列的分析是可行的。 相似文献
976.
LI Yu-jiang YANG Min ZHANG Xiao-jin WU Tao CAO Nan WEI N BI Yan-jun WANG Jing 《环境科学学报(英文版)》2006,18(1):23-28
A hydrotalcite with Mg/AI molar ratio 2 was prepared by co-precipitation method and was characterized by XRD, TG/DTA, Zeta potential and BET surface area. The hydrotalcite was calcined at 500℃, with the dehydration from interlayer, the dehydroxilation from the brucite-like layer and the decomposition of carbonate successively, transformed into the mixed oxide type. The removal of thiocyanate from aqueous solution by using the original hydrotalcite and calcined hydrotalcite (HTC-500) was investigated. The results showed that the thiocyanate adsorption capacity of calcined hydrotalcite was much higher than that of the original form. Calcined hydrotalcite was particularly effective at removing thiocyanate, and that the effective range of pH for the thiocyanate removal are between 5.5-10.0. The experimental data of thiocyanate removal fit nicely with Langmuir isotherm, and the saturated adsorption uptake was 96.2 mg SCN-/g HTC-500. The adsorption of thiocyanate by calcined hydrotalcite follows first-order kinetics. And the intercalation to the structure recovery for calcined hydrotalcite. But the presence of additional anions could affect the adsorption behavior of thiocyanate. 相似文献
977.
978.
推进地震安全农居工程 总被引:1,自引:0,他引:1
2006年10月,在山东省召开的全省农村民居防震保安工作电视会议上,张昭福副省长曾指出,各级部门必须认清形势,提高认识,切实增强做好农村民居防震保安工作的责任感和紧迫感。他要求各级部门要把地震安全农居工程作为一件大事来抓,尽快改变农村抗震能力薄弱的现状。 相似文献
979.
目的 改善2219铝合金钨极氩弧焊焊缝的耐腐蚀性能。方法 采用激光冲击技术对焊缝进行强化处理,比较分析处理前后的表面残余应力、物相组成和元素状态,通过静态浸泡失重法和电化学试验测量腐蚀速率的变化。结果 经过激光冲击强化处理后,2219铝合金焊缝部位的元素状态没有改变,但焊缝区域的残余拉应力变为残余压应力。2219铝合金钨极氩弧焊接区域的自腐蚀电位明显下降,相比未经激光冲击处理的试件,焊核区和焊接过渡区的平均腐蚀电流分别减小了14%和12.7%,腐蚀速率分别减小了16.9%和12.9%。结论 激光冲击强化可以有效提升2219铝合金钨极氩弧焊焊缝区域的耐腐蚀性能,可以为提升特种装备安全性和轻量化提供技术参考。 相似文献
980.
Yasong Li Shasha Yin Shijie Yu Ling Bai Xudong Wang Xuan Lu Shuangliang Ma 《环境科学学报(英文版)》2021,33(1):354-368
In this study, we conducted an observation experiment from May 1 to June 30, 2018 in Zhengzhou, a major city in central China, where ground ozone (O3) pollution has become serious in recent years. The concentrations of O3 and its precursors, as well as H2O2 and meteorological data were obtained from the urban site (Yanchang, YC), suburban (Zhengzhou University, ZZU) and background sites (Ganglishuiku, GLSK). Result showed that the rates of O3 concentration exceeded Chinese National Air Quality Standard Grade II (93.3 ppbv) were 59.0%, 52.5%, and 55.7% at the above three sites with good consistency, respectively, indicating that O3 pollution is a regional problem in Zhengzhou. The daily peak O3 appeared at 15:00–16:00, which was opposite to VOCs, NOx, and CO and consistent with H2O2. The exhaustive statistical analysis of meteorological factors and chemical effects on O3 formation at YC was advanced. The high concentration of precursors, high temperature, low relative humidity, and moderately high wind speed together with the wind direction dominated by south and southeast wind contribute to urban O3 episodes in Zhengzhou. O3 formation analysis showed that reactive alkenes such as isoprene and cis-2-butene contributed most to O3 formation. The VOCs/NOx ratio and smog production model were used to determine O3-VOC-NOx sensitivity. The O3 formation in Zhengzhou during early summer was mainly under VOC-limited and transition regions alternately, which implies that the simultaneous emission reduction of alkenes and NOx is effective in reducing O3 pollution in Zhengzhou. 相似文献