Temporal distribution and potential sources of atmospheric mercury measured at a high-elevation background station in Taiwan

Measurements of gaseous elemental mercury (GEM), reactive gaseous mercury (RGM), and particulate mercury (PHg) have been conducted at Lulin Atmospheric Background Station (LABS) in Taiwan since April 2006. This was the first long-term free tropospheric atmospheric Hg monitoring program in the downwind region of East Asia, which is a major Hg emission source region. Between April 13, 2006 and December 31, 2007, the mean concentrations of GEM, RGM, and PHg were 1.73 ng m^?3, 12.1 pg m^?3, and 2.3 pg m^?3, respectively. A diurnal pattern was observed for GEM with afternoon peaks and nighttime lows, whereas the diurnal pattern of RGM was opposite to that of GEM. Spikes of RGM were frequently observed between midnight and early morning with concurrent decreases in GEM and relative humidity and increases in O₃, suggesting the oxidation of GEM and formation of RGM in free troposphere (FT). Upslope movement of boundary layer (BL) air in daytime and subsidence of FT air at night resulted in these diurnal patterns. Considering only the nighttime data, which were more representative of FT air, the composite monthly mean GEM concentrations ranged between 1.06 and 2.06 ng m^?3. Seasonal variation in nighttime GEM was evident, with lower concentrations usually occurring in summer when clean marine air masses prevailed. Between fall and spring, air masses passed the East Asian continent prior to reaching LABS, contributing to the elevated GEM concentrations. Analysis of GEM/CO correlation tends to support the argument. Good GEM/CO correlations were observed in fall, winter, and spring, suggesting influence of anthropogenic emission sources. Our results demonstrate the significance of East Asian Hg emissions, including both anthropogenic and biomass burning emissions, and their long-range transport in the FT. Because of the pronounced seasonal monsoon activity and the seasonal variation in regional wind field, export of the Asian Hg emissions to Taiwan occurs mainly during fall, winter, and spring.     

地表水中溶解氧监测及变化规律

采用碘-淀粉光度法对连云港大浦河水域中溶解氧进行测定,并对其日变化、季节变化和垂直分布及变化规律进行了分析。     

阿尔泰多拉纳萨依金矿床初探

新疆多拉纳萨依金矿床位于阿尔泰克兰海西褶皱带玛尔卡库里大断裂的西南侧,西与苏联矿区阿尔泰之列宁诺戈尔斯克—孜里亚诺夫斯克构造成矿亚带相接。地层为中泥盆统托克萨雷组浅变质岩,大致呈南北走向的长条状分布在三个斜长花岗岩侵入体之间,并有许多钠长斑岩岩脉穿插。主要构造线方向为北北东,向西倾斜。金矿体赋存在沿断裂带侵入于灰岩中的石英钠长岩(或钠长石化斜长花岗岩)中。蚀变围岩主要为千糜岩化、白云母化的石英钠长岩。石英脉中金的品位虽然较高,但工业储量主要赋存于蚀变围岩中。自然金主要以显微和次显微状独立矿物被包裹于黄铁矿等矿物中,成色很高(932—967),其中的少量元素为银、汞和铋。为与斜长花岗岩有关的岩浆期后高—中温热液充填—交代矿床。     

蕨类植物中的Υ辐射体

报道了对七种蕨类植物作γ能谱分析的结果。铁芒萁及乌毛蕨对~(232)Th放射性系列的辐射子体吸收率很高。铁芒萁的~(223)Ac含量约为附近树叶的20倍,树枝的80倍,草的40倍。计算了芒萁对各γ辐射体的富集比率。铁芒萁和乌毛蕨可作为土壤中钍系含量的指标植物。人们应避免使用干蕨作为燃料。     

基于社会成本下农用化学品最优使用量的探讨

分析了农用化学品使用的现状及其对环境的负面影响，重点探讨了考虑社会总成本时农用化学品最优使用量的确定，介绍了农用化学品使用环境成本的核算方法。     

超声波强化污水生物处理的可行性探讨

通过对超声波空化处理难降解有机废水机理和超声波辐射促进微生物活性作用机制的分析研究，提出将超声波应用于强化污水生物处理的可行性。同时设计了利用超声波空化反应单元作为污水生物处理的前处理工艺，提高污水的可生化性，和在生物处理反应器中直接进行超声波辐射提高生物处理能力的工艺。分析了超声波强化污水生物处理的影响因素，并对未来的研究方向进行了展望。     

北京城区雨水径流水质及其主要影响因素

掌握城区雨水径流水质及其主要的影响因素是有效地利用城区雨水资源和控制城市非点源污染的基础。根据北京 1998— 2 0 0 0年大量的降雨径流水质数据 ,本文分析了城区屋面和道路雨水径流的水质变化规律及其主要影响因素城市雨水径流的水质很差 ,初期径流的污染程度甚至超过城市污水。除了空气质量的影响外 ,最重要的影响因素是屋面材料、道路类型及路面污染状况、气温、降雨强度、降雨量和降雨间隔时间等     

活性炭纤维吸附-催化燃烧装置处理有机废气

介绍一种处理有机废气的吸附－催化燃烧新型装置，以活性炭纤维为吸附剂，结合多单元分流组合式中附床，采用PLC电脑来实现整个系统的连续运行。实验运行结果表明，对于处理大风量，低浓度的有机废气，该技术与其他技术相比具有净化效率高，节能降耗，自动化水平高等优点。     

高羊茅对微牛物强化修复石油污染土壤影响的研究

进行了石油污染土壤在外源微生物菌剂和高羊茅协调作用下的强化修复试验，对外源微生物菌剂在不同植被条件下的去除特征进行了分析。分别进行了没有植物、高羊茅草坪、高羊茅草种新育草坪3种不同情况下的降解试验。结果表明，微生物菌剂对石油污染土壤有着良好的降解效果，去除率为36％-43％，而没有微生物菌剂和植被作用下的对照组的去除率仅为5．74％～6．0％；高羊茅草坪能够提高微生物进一步降解的能力，在直接铺草坪的情况下，去除率可以达到51％～62％；在播种高羊茅草种，形成新嫩草坪的情况下，去除率为48％～54％。结果表明，在直接铺高羊茅草坪条件下，微生物菌剂的强化分解作用可以提高41．6％-44．2％，在新嫩草坪作用下能够提高27．9％-30．6％，可以认为高羊茅草坪对于提高微生物菌剂的强化分解有一定的促进作用。在试验过程中还对不同修复的土壤pH值变化特性进行了分析。     

Modeling time-dependent toxicity to aquatic organisms from pulsed exposure of PAHs in urban road runoff

Understanding of the magnitude of urban runoff toxicity to aquatic organisms is important for effective management of runoff quality. In this paper, the aquatic toxicity of polycyclic aromatic hydrocarbons (PAHs) in urban road runoff was evaluated through a damage assessment model. Mortality probability of the organisms representative in aquatic environment was calculated using the monitored PAHs concentration in road runoff. The result showed that the toxicity of runoff in spring was higher than those in summer. Analysis of the time-dependent toxicity of series of runoff water samples illustrated that the toxicity of runoff water in the final phase of a runoff event may be as high as those in the initial phase. Therefore, the storm runoff treatment systems or strategies designed for capture and treatment of the initial portion of runoff may be inappropriate for control of runoff toxicity.