美国EPA完成固定式发动机清洁空气标准修改

为执行和解协议,美国环保署最后修改标准以减少固定式发努机所造成的空气污染,这包括了工业、农业、油气产品、电厂和其他设施中的产生电力和能源的设备.宣布的最后修改条例中指出,将在2010年的基础上,分别减少2.87亿美元和1.39亿美元的基建投资和年度费用,     

Photocatalytic activity of TiO2 containing anatase nanoparticles and rutile nanoflower structure consisting of nanorods

A series of TiO2 with different crystal phases and morphologies was synthesized via a facile hydrothermal process using titanium nbutoxide and concentrated hydrochloric acid as raw materials. The photocatalytic activity of the samples was evaluated by degradation of Methyl Orange in aqueous solution under UV-Visible light irradiation. On the basis of detailed analysis of the characterizing results of high-resolution transmission electron microscopy, X-ray powder diffraction measurements, X-ray photoelectron spectroscopy and Brunauer-Emmett-Teller measurement, it was concluded that the photo-activity of the catalyst is related directly to the 3D morphology and the crystal phase composition. An excellent catalyst should have both a futile 3D flower-like structure and anatase granulous particles. The 3D flower-like structure could enhance light harvesting, as well as the transfer of reactant molecules from bulk solution to the reactive sites on TiO2. In addition, the optimum anatase/rutile phase ratio was found to be 80：20, which is beneficial to the effective separation of the photogenerated electron-hole pairs.     

Electrochemical and spectroscopic characteristics of dissolved organic matter in a forest soil profile

Dissolved organic matter （DOM） represents one of the most mobile and reactive organic compounds in ecosystem and plays an important role in the fate and transport of soil organic pollutants, nutrient cycling and more importantly global climate change. Electrochemical methods were first employed to evaluate DOM redox properties, and spectroscopic approaches were utilized to obtain information concerning its composition and structure. DOM was extracted from a forest soil profile with five horizons. Differential pulse voltammetry indicated that there were more redox-active moieties in the DOM from upper horizons than in that from lower horizons. Cyclic voltammetry further showed that these moieties were reversible in electron transfer. Chronoamperometry was employed to quantify the electron transfer capacity of DOM, including electron acceptor capacity and electron donor capacity, both of which decreased sharply with increasing depth. FT-IR, UV-Vis and fluorescence spectra results suggested that DOM from the upper horizons was enriched with aromatic and humic structures while that from the lower horizons was rich in aliphatic carbon, which supported the findings obtained by electrochemical approaches. Electrochemical approaches combined with spectroscopic methods were applied to evaluate the characteristics of DOM extracted along a forest soil profile. The electrochemical properties of DOM, which can be rapidly and simply obtained, provide insight into the migration and transformation of DOM along a soil profile and will aid in better understanding of the biogeochemical role of DOM in natural environments.     

基于阳离子树脂的Fenton非均相催化剂制备及性能测试

采用阳离子交换树脂颗粒为催化剂载体采用浸渍法负载二价铁离子,制备出非均相Fenton反应催化剂,并用该非均相Fenton催化剂氧化脱色亚甲基蓝溶液,考察其催化性能。实验结果表明:制备催化剂时最佳FeSO4浓度为16.67 mmol/L,pH=3.0,H2O2初始浓度为46.6 mmol/L,反应时间为30 min的条件下,亚甲基蓝溶液初始浓度为0.028 mmol/L时,亚甲基蓝溶液在非均相Fenton催化氧化过程中,其脱色率可达92.9%。采用序批形式反应使用5次后,该非均相催化剂仍有良好的催化效果,反应30 min后亚甲基蓝溶液脱色率仍可达85.2%,拓宽了Fenton技术的使用范围。     

浅谈城市交通空气污染治理

空气污染是困扰当今世界上成千上万城市的重大环境问题。人类社会发展到二十一世纪,其赖以存活的空气环境的污染程度已对健康和生存构成巨大威胁。我国约有4亿多城市居民生活在不符合基本健康要求的空气中,而造成空气污染的其中一个主要原因就是交通排放污染。     

中国环境科学研究院与瑞士发展合作署共同举办“中瑞清洁空气行动计划研讨会”

2013年11月7—8日中国环境科学研究院与瑞士发展合作署共同举办“中瑞清洁空气行动计划研讨会”。开幕式由中国环境保护部污染防治司汪键副司长、中国环境科学研究院柴发合副院长及瑞士环保署大气污控与化学品管理司马丁西斯司长先后致辞,分别向参会人员介绍了中瑞两国大气污染现状及研讨会举办的背景和意义等。     

《清洁空气研究计划》启动会在京举行

2013年9月29日环境保护部为贯彻落实国务院日前刚刚发布的《大气污染防治行动计划》（以下简称《行动计划》）,加强科技支撑,组织召开了会议,正式启动《清洁空气研究计划》（以下简称《研究计划》）并成立领导小组和总体专家组。启动会由环境保护部总工程师万本太主持。环境保护部副部长吴晓青出席会议并讲话。《研究计划》领导小组、总体专家组以及部分直属单位领导参加了会议。     

γ-Fe_2O_3/膨胀石墨复合材料吸附废水中六价铬的应用研究

介绍了采用溶胶凝胶法合成新型的复合材料-磁性的γ-Fe_2O_3膨胀石墨(MEG)复合材料。通过采用X-射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)以及X-光电子能谱仪(XPS)对该复合材料MEG进行了表征,结果表明MEG中γ一Fe_2O_3的粒径约为50nm,而且其中γ一Fe_2O_3和膨胀石墨通过C=O相互作用。复合材料MEG作为新型的六价铬吸附剂,通过吸附时间、初始溶液的pH值以及再生性对该吸附过程进行了考察。结果表明:在40 min内MEG吸附六价铬的过程基本达到平衡;在初始溶液的pH为3.5时,MEG对六价铬的最大吸附量可以达到16.4mg/g;而且该复合材料MEG重复使用3次后吸附效果基本没有下降。因此,复合材料MEG对于废水中六价铬的处理有选择性吸附作用,而且初始溶液的pH值对其吸附过程起着重要作用。     

浅谈环境空气自动监测站质控方式

采用标准样品检查、PM10采样流量检查和运行管理检查等方式,加强对云南省环境空气自动监测站的质量管理和质量控制,保证了仪器设备的可靠运行和监测数据准确有效。实践证明,这套检查方式操作简单、易于实施、效果较好。     

基于LandsatTM数据的济宁市水体识别方法研究

文章基于济宁市2009年LANDSAT TM影像,根据影像各波段间的相关性和地物在各影像上的灰度差异,分别采用单波段阈值法、多波段谱间关系法、改进的水体指数法(MNDWI)及HIS空间水体提取模型法对济宁市水体信息进行识别提取。在此基础上,结合归一化指数法和HIS空间水体提取模型,提出了一种综合性的水体信息提取方法,并对各方法提取结果进行了精度评价。结果表明,已有方法对济宁市水体识别存在一定的缺陷,而综合法集成了归一化指数法和HIS空间水体模型的优点,很好地弥补了已有方法的不足,对济宁市水体信息进行了较好的提取,尤其是细小水体,同时也很好地消除了建筑物、阴影、水生植被等的影响,提高了济宁市水体信息识别的精度,为更好地定量评价济宁市地表水体时空演变规律等提供帮助。