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751.
土地革命时期,中共在湖北建立了广大的苏区,为了保护军民健康、保障部队战斗力、改善民众生活状况,各苏区努力开展防疫减灾事业,建设红军医院、救治军民、普及防疫减灾知识,此举有效治疗了军民的伤病,提高了民众的防疫减灾意识、保障了苏区的巩固发展。 相似文献
752.
753.
The high content of alkali chlorides in municipal solid waste incineration(MSWI) fly ash limit its resource reuse due to the potential environmental risks.In this paper, with superheated steam as the gasifying agent and inducer, chlorides in fly ash were removed by thermal treatment within a moderate temperature range.Thermal treatment experiments were performed under different conditions: temperature(500–800℃), steam addition(mass ratio of steam to fly ash = 0.25–1) and residence time(0.5–3 hr).Iron and aluminum powders were added to fly ash to improve the chlorine removal efficiency.Water-soluble chlorides included Na Cl and KCl, and insoluble chlorides mainly included Ca(OH)Cl.The heating process with the addition of water steam was more efficient than that without steam in terms of the removal performance of water-soluble chlorides.The removal efficiency of soluble chlorides reached 75.25% for a mass ratio of 1:1 after 1-hr thermal treatment at 700℃.When the residence time was increased above 1 hr, the total dechlorination efficiency was not increased dramatically.Moreover, adding iron and aluminum powder into the fly ash improved the removal of water-insoluble chlorides, and the total dechlorination efficiency was increased by 11.41%–16.64%. 相似文献
754.
Yi Li Hua Zhang Zongshan Zhao Yong Tian Kun Liu Feifan Jie Liang Zhu Huanwen Chen 《环境科学学报(英文版)》2018,30(5):287-293
Particulate matters(PMs) emitted by automobile exhaust contribute to a significant fraction of the global PMs. Extractive atmospheric pressure chemical ionization mass spectrometry(EAPCI-MS) was developed to explore the molecular dependence of PMs collected from exhaust gases produced at different vehicle engine speeds. The mass spectral fingerprints of the organic compounds embedded in differentially sized PMs(e.g., 0.22–0.45, 0.45–1.00, 1.00–2.00, 2.00–3.00, 3.00–5.00, and 5.00–10.00 μm) generated at different engine speeds(e.g., 1000, 1500, 2000, 2500, and 3000 r/min) were chemically profiled in the mass range of mass to charge ratio(m/z) 50–800. Organic compounds,including alcohols, aldehydes, and esters, were detected in all the PMs tested, with varied concentration levels for each individual PM sample. At relatively low engine speeds(≤ 1500 r/min), the total amount of organic species embedded in PMs of 0.22–1.00 μm was greater than in PMs of other sizes, while more organic species were found in PMs of5.00–10.00 μm at high engine speeds(≥ 3000 r/min), indicating that the organic compounds distributed in different sizes of PMs strongly correlated with the engine speed. The experimental data showed that the EAPCI-MS technique enables molecular characterization of PMs in exhaust, revealing the chemical dependence of PMs on the engine speeds(i.e., the combustion conditions) of automobiles. 相似文献
755.
Myat Sandar Win Zhengyang Tian Hui Zhao Kai Xiao Jiaxian Peng Yu Shang Minghong Wu Guangli Xiu Senlin Lu Shinich Yonemochi Qingyue Wang 《环境科学学报(英文版)》2018,30(9):13-31
Atmospheric humic-like substances(HULIS) are not only an unresolved mixture of macroorganic compounds but also powerful chelating agents in atmospheric particulate matters(PMs); impacting on both the properties of aerosol particles and health effects by generating reactive oxygen species(ROS). Currently, the interests of HULIS are intensively shifting to the investigations of HULIS-metal synergic effects and kinetics modeling studies, as well as the development of HULIS quantification, findings of possible HULIS sources and generation of ROS from HULIS. In light of HULIS studies, we comprehensively review the current knowledge of isolation and physicochemical characterization of HULIS from atmospheric samples as well as HULIS properties(hygroscopic, surface activity, and colloidal) and possible sources of HULIS.This review mainly highlights the generation of reactive oxygen species(ROS) from PMs, HULIS and transition metals, especially iron. This review also summarized the mechanism of ironorganic complexation and recent findings of OH formation from HULIS-metal complexes. This review will be helpful to carry out the modeling studies that concern with HULIS-transition metals and for further studies in the generation of ROS from HULIS-metal complexes. 相似文献
756.
对长江中下游 南黄海地震带地震活跃期、幕划分及其发展趋势进行了研究,对江苏及其邻区今后几年的地震大形势及重点危险区进行了判定。分析认为,长南带从1971年以来进入第二活跃期的第3幕,该幕地震活动将持续到2010年前后,最高活动水平为6.5级左右。今后几年江苏东部至南黄海海域发生5~6级或6级以上地震的可能性较大。 相似文献
757.
Fe(Ⅲ)水解过程中无机阴离子的影响作用 总被引:18,自引:5,他引:18
本文通过PO^3- 4,F^-,SO^2- 4,Cl^-,NO^- 3和ClO^- 4存在时,0.1mol/1 FeCl3溶液的碱中和曲线的分析对比,说明了用曲线斜率区分滴定曲线为三个区域:(A)自发水解反应;(B)聚合反应;(C)沉淀反应,以及阴离子对中和曲线的影响及其规律,指出阴子子对Fe(Ⅲ)浓度中和反应影响为不同程度的竞争配位,参与聚合及电中和脱稳,使沉淀反应提前等。并与OH^-共同形成F 相似文献
758.
拟除虫菊酯在不同猝灭体系中的光化学降解 总被引:5,自引:0,他引:5
本文选择了具有抗氧作用或光屏蔽作用的六种物质,测定了它们在不同浓度配比,不同光照时间,不同充气条件下对这四种拟除虫菊光解稳定性的影响,结果表明,它们对拟除虫菊酯有不同程度的光稳定作用,光屏蔽型稳定对浓度的变化更为敏感,耗氧型稳定剂由于自身的消耗对光照时间,充氧条件为敏感,由此可见,不同的环境条件对拟除虫菊酯类农药的残留产生较大影响,同时,使用光稳剂将是一种增强拟除虫菊酯光稳定性,充分发挥杀虫作用的 相似文献
759.
长春市南湖大气降尘长期演变规律 总被引:1,自引:0,他引:1
本文统计分析了1984-1993年长春市南湖大气降尘数据,探讨了冬季与夏季的代表月份以及10年间的代表年份大气降尘长期演变规律。10年间冬季降法量呈波浪式递减趋势;从统计来看,冬季1月份降尘最是夏季7朋份降尘量的2.3倍左右;同年度内冬季、春季大风时段的除尘量一般高于夏、秋季;冬季煤烟型大气污染已逐年在所改善,一些自然因素对大气除尘的影响逐渐突出。 相似文献
760.
填埋结构对渗滤液中氨氮脱除的影响 总被引:3,自引:0,他引:3
建立了模拟填埋试验中试装置,研究了准好氧填埋渗滤液NH3-N的变化特性和稳定期垃圾对渗滤液NH3-N的处理效果.结果表明,准好氧填埋结构下渗滤液NH3-N衰减很快,下降率可达99.6%,没有出现传统填埋场累积的现象,为渗滤液后续处理解决了氨氮浓度过高的难题;随着水力负荷的增大,NH3-N的去除率呈下降趋势,去除率由低水力负荷时的99.9%,下降到高水力负荷时的87.7%;准好氧填埋垃圾对低可生化性、高浓度氨氮的渗滤液有很好的处理能力,但反硝化能力不足;较高有机物浓度有利于反硝化作用,使氨氮彻底转化为氮气. 相似文献