以PHBV为固相碳源同时去除地下水中硝酸盐氮和对氯苯酚的试验研究

化肥和农药的施用导致中国的地下水中硝酸盐氮和农药污染同时存在,并成为威胁人体健康的重要因素之一。其中氯酚类物质是一类常见的农药,具有高毒性和难降解性。目前,关于固相反硝化用于硝酸盐氮和对氯苯酚同时去除的研究较少,并且对微生物群落结构演变情况的分析还鲜见报道。论文以聚羟基丁酸戊酸共聚酯(PHBV)为反硝化固体碳源,通过序批试验研究同步去除硝酸盐氮和对氯苯酚的效果,并探讨对氯苯酚的加入对反硝化速率的影响;利用末端限制性长度多态性分析(T-RFLP)技术,使用Alu I酶切总细菌16S r RNA,研究对氯苯酚的存在对微生物群落的影响。结果表明,(1)在50 mg·L-1的硝酸盐氮(NO3--N)的浓度水平下,对氯苯酚(4-CP)的加入前后,硝酸盐氮(NO3--N)的去除率为(97.5±1.2)%和(95.3±1.7)%,总体上使去除效果略有降低;在10 mg·L-1的质量浓度水平下,对氯苯酚24 h的平均去除率为45.4%,其去除85.5%是由于微生物的降解作用引起的。(2)从对氯苯酚的加入到第45天的时间内,反硝化速率表现为先下降后上升,说明对反硝化速率起到先抑制后促进的作用。(3)在对氯苯酚加入前后45 d内,系统微生物群落结构发生明显的变化,趋向于多样化和均匀化。     

“2014.5.10”云南怒江州福贡泥石流成因分析

2004年5月10日云南怒江州福贡县石月亮乡发生泥石流等地质灾害,造成人员、经济重大损失。分析了此次泥石流形成的条件,并着重探讨了天气学成因,结果表明:脆弱的地质环境、陡峻的迎风坡、便于集水、集物的地形地貌和丰富的松散物质是怒江贡山泥石流易发生的有利地质地貌条件;连续性累积降水及短时间暴雨的产生为泥石流提供了较好的水源条件;高原短波槽与孟加拉湾南支槽东移合并,中、低层槽前西偏南暖湿气流500 h Pa偏西北气流是形成怒江暴雨过程的大尺度天气环流背景;地面辐合线、干线、低层显著湿区、湿舌等是导致降水的中尺度系统;高能高湿的潜在不稳定及近地层的水汽辐合是暴雨发生的有利条件;多普勒雷达图10~20 d Bz分散的絮状回波、部分35 d Bz块絮状回波、卫星云图多絮状对流云、无强对流云团活动反映此次暴雨过程为非对流性暴雨。     

2013年北川聚落空间的地质灾害灾情分析

北川羌族自治县是2008年汶川8.0级地震的极重灾区之一。2013年7月8-12日,北川县境内普降暴雨,引起地质灾害事件大面积爆发。洪灾之后的灾情普查数据表明,县域内共有1 318个居民点受到各类地质灾害的威胁,这些地质灾害点的类型多样、分布广泛并且所造成的危害严重。根据灾情普查数据,按乡镇单元提取了各自的灾害点数量、受威胁面积、受威胁户数、受威胁人数、受威胁财产以及防治费用等6个指标,采用主成分分析方法来进行地质灾害灾情的综合评价,根据各乡镇的综合得分对乡镇的灾情进行了排序。这个评价结果较好地反映了各乡镇之间的灾情差异,也为上一级政府进行诸如制定乡镇社会经济发展指标、决定防灾减灾资金及技术力量的投向等行政决策提供了直接依据。     

纳米铜颗粒的种间毒性关系

纳米颗粒的种间毒性关系尚无明确结论,因此很难判断纳米颗粒对未进行毒性测试的物种的风险如何。本文作者将5种水蚤(Daphnia magna, Daphnia pulex, Daphnia galeata, Ceriodaphnia dubia, Chydorus sphaericus)暴露于4种不同粒径的纳米铜颗粒(CuNPs)和1种亚微米铜颗粒的悬浊液中,考察物种的形态特征与CuNPs急性毒性的关系。结果显示,杆状的CuNPs比球状的CuNPs毒性更低。纳米铜颗粒与溶出铜离子均对CuNPs的毒性有贡献,其中,当新生蚤的体长、体表面积和身体体积更小时,5种悬浊液中颗粒的毒性更大。5种蚤的身体体积与5种CuNPs的毒性显著相关(r_adj²>0.51, p < 0.001),78-nm CuNPs与蚤身体体积的相关性最好 (r_adj²?=?0.95, p < 0.001)。这个研究可以为纳米颗粒对有相似外形特征的物种进行毒性种间外推提供线索。
精选自Lan Song, Martina G. Vijver, Geert R. de Snoo and Willie J.G.M. Peijnenburg. Assessing toxicity of copper nanoparticles across five cladoceran species. Environmental Toxicology and Chemistry: Volume 34, Issue 8, pages 1744–1750, August 2015. DOI: 10.1002/etc.3000
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3000/full     

云南兰坪县城滑坡地质特征及其成因分析

2000年9月兰坪县城发生特大型山体滑坡,造成重大经济损失,采取挡墙、抗滑桩等措施后,北部边坡局部基本稳定,南部依见明显新变形,2010~2013年尤甚。基于滑坡现状特征及区域地质环境条件分析,提出了以隐伏断裂(F2)为界将滑坡区重新分块,能够合理反映滑坡的变形破坏特征,并为类似滑坡地质勘察加强针对隐伏断裂的影响分析具有重要的借鉴意义。通过分析滑坡体地质及变形破坏特征,认为滑坡的成因主要受控于滑坡区发育的不利岩性条件及地质结构面,水~岩作用是导致岩体崩解破坏诱发滑坡的主要因素。     

Effects of two polybrominated diphenyl ethers (BDE-47, BDE-209) on the swimming behavior,population growth and reproduction of the rotifer Brachionus plicatilis

Polybrominated diphenyl ethers(PBDEs) are new kinds of persistent organic pollutants(POPs) and their potential threats to the equilibrium and sustainability of marine ecosystems have raised worldwide concerns. Here, two kinds of PBDEs, tetra-BDE(BDE-47)and deca-BDE(BDE-209) were applied, and their toxic effects on the swimming behavior,population growth and reproduction of Brachionus plicatilis were investigated. The results showed that:(1) The actual concentrations of BDE-47 and-209 in the seawater phase measured by GC–MS(Gas Chromatography-Mass Spectrometer) were much lower than their nominal concentrations.(2) In accordance with the 24-hr acute tests, BDE-209 did not show any obvious swimming inhibition to rotifers, but a good correlation did exist between the swimming inhibition rate and BDE-47 concentration suggesting that BDE-47 is more toxic than BDE-209.(3) Both BDE-47 and-209 had a significant influence on the population growth and reproduction parameters of B. plicatilis including the population growth rate, the ratio of ovigerous females/non-ovigerous females(OF/NOF), the ratio of mictic females/amictic females(MF/AF), resting egg production and the mictic rate, which indicate that these parameters in B. plicatilis population were suitable for monitoring and assessing PBDEs. Our results suggest that BDE-47 and-209 are not acute lethal toxicants and may pose a low risk to marine rotifers at environmental concentrations for short-term exposure. They also accumulate differently into rotifers. Further research data are needed to understand the mechanisms responsible for the effects caused by PBDEs and to assess their risks accurately.     

轻质油中间原料储罐腐蚀现状及对策

对近年来加工原料劣质化后轻质油中间原料储罐腐蚀问题突出和腐蚀导致的安全事故多发的现状进行了论述,介绍了中国石化轻质油中间原料储罐的调研情况和发现的主要问题,从多个方面提出了轻质油中间原料储罐的防腐对策.     

黑碳气溶胶的测量方法对比研究

大气黑碳气溶胶主要有光学分析法、热学分析法以及热光结合分析法。利用苏州南门国控子站的碳分析数据,对三种黑碳浓度测量方法进行对比并分析其差异来源。主要得出以下结论:黑碳仪衰减系数无普适标准,热学分析法使有机碳碳化、元素碳不完全分离,TOT法协议设置存在争议是三种方法存在差异的主要原因。     

Trends of the sunshine duration and diffuse radiation percentage on sunny days in urban agglomerations of China during 1960–2005

The long-term observational data of sunshine duration (SD) and diffuse radiation percentage (defined as diffuse solar radiation/total solar radiation, DRP) on sunny days during 1960–2005 were analyzed in 7 urban agglomerations and the whole of China. The results show that the sunny sunshine duration (SSD) has decreased significantly except at a few stations over northwestern China in the past 46 years. An obvious decrease of the SSD is found in eastern China, with the trend coefficients lower than − 0.8. Accompanied by the SSD decline, the sunny diffuse radiation percentage (SDRP) in most stations shows obvious increasing trends during the 46 years. The averaged SDRP over China has increased 2.33% per decade, while the averaged SSD shows a decrease of − 0.13 hr/day per decade. The correlation coefficient between SDRP and SSD is − 0.88. SSD decreased over urban agglomerations (small to large city clusters) in the past 46 years, especially in large cities and medium cities, due to the strong anthropogenic activities and air pollution represented by aerosol option depth (AOD) and tropospheric column NO₂ (TroNO₂). On the regional scale, SSD has an opposite trend from SDRP during 1960 to 2005, and the variation trends of regional mean values of SSD and SDRP in southeastern China are more pronounced than those in northwestern China.     

超声雾化法捕集气溶胶的试验研究

核设施退役过程,放射性气溶胶浓度较高,需要进行处理,以降低工作人员辐照风险。研究捕集剂配方、雾化通入量等对模拟气溶胶捕集效果的影响,结果表明:捕集剂配方对气溶胶捕集的效果差异明显;粒径越小的气溶胶粒子被雾化捕集的速度较慢;捕集剂通入量在0.06 kg/m3以下,对气溶胶捕集效果影响显著。对等离子切割解体设备产生的241Am、239Pu污染气溶胶进行雾化捕集,初始污染水平为136 Bq/m3的气溶胶经雾化捕集后可降至1.23 Bq/m3,捕集的效果显著。