Satellite observations of Mexico City pollution outflow from the Tropospheric Emissions Spectrometer (TES)

Concurrent tropospheric O₃ and CO vertical profiles from the Tropospheric Emission Spectrometer (TES) during the MILAGRO/INTEX-B aircraft campaigns over the Mexico City Metropolitan Area (MCMA) and its surrounding regions were used to examine Mexico City pollution outflow on a regional scale. The pollution outflow from the MCMA occurred predominantly at 600–800 hPa as evident in O₃, CO, and NO_x enhancements in the in situ aircraft observations. TES O₃ and CO are sensitive to the MCMA pollution outflow due to their relatively high sensitivities at 600–800 hPa. We examined O₃, CO, and their correlation at 600–800 hPa from TES retrievals, aircraft measurements, and GEOS-Chem model results. TES captures much of the spatial and day-to-day variability of O₃ seen in the in situ data. TES CO, however, shows much less spatial and day-to-day variability compared with the in situ observations. The ΔO₃/ΔCO slope is significantly higher in the TES data (0.43) than the in situ data (0.28) due partly to the lack of variability in TES CO. Extraordinarily high ΔO₃/ΔCO slope (0.81) from TES observations at 618 hPa over the Eastern U.S. was previously reported by Zhang et al. [Zhang, L., Jacob, D.J., Bowman, K.W., et al., 2006. Ozone–CO correlations determined by the TES satellite instrument in continental outflow regions. Geophys. Res. Lett. 33, L18804. 10.1029/2006GL026399.]. Thus the application of TES CO–O₃ correlation to map continental pollution outflow needs further examination.     

Regional differences and sources of organochlorine pesticides in soils surrounding chemical industrial parks

Concentrations of organochlorine pesticides (OCPs; dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB)) were investigated in 105 soil samples collected in vicinity of the chemical industrial parks in Tianjin, China. OCP concentrations significantly varied in the study area, high HCH and DDT levels were found close to the chemical industrial parks. The intensity of agricultural activity and distance from the potential OCP emitters have important influences on the OCP residue distributions. Principal component analysis indicates that HCH pollution is a mix of historical technical HCH and current lindane pollution and DDT pollution input is only due to technical DDT sources. The significant correlations of OCP compounds reveal that HCHs, DDTs and HCB could have some similar sources of origin.     

分光光度法与离子色谱法测定空气中氯化氢的对比研究

通过对硫氰酸汞分光光度法和离子色谱法测定空气中氯化氢含量的对比发现，两种方法对实验室质控样和实际样品的分析测定均能达到要求，且F检验法分析表明实测结果没有显著性差异。然而，硫氰酸汞分光光度法的测试过程操作繁琐，误差较大，稳定时间较长，且硫氰酸汞具有剧毒，危害操作人员的健康，残液也难以处理。离子色谱法分析操作简单，过程安全可靠，能够有效降低样品受污染的可能性并保证分析质量。     

The algal toxicity of silver engineered nanoparticles and detoxification by exopolymeric substances

In this study, we report that silver ions (Ag⁺) from the oxidative dissolution of silver engineered nanoparticles (Ag-ENs) determined the EN toxicity to the marine diatom Thalassiosira weissflogii. Most of the Ag-ENs formed non-toxic aggregates (>0.22 μm) in seawater. When the free Ag⁺ concentration ([Ag⁺]_F) was greatly reduced by diafiltration or thiol complexation, no toxicity was observed, even though the Ag-ENs were better dispersed in the presence of thiols with up to 1.08 × 10⁻⁵ M Ag-ENs found in the <0.22 μm fraction, which are orders of magnitude higher than predicted for the natural aquatic environment. The secretion of polysaccharide-rich algal exopolymeric substances (EPS) significantly increased at increasing [Ag⁺]_F. Both dissolved and particulate polysaccharide concentrations were higher for nutrient-limited cells, coinciding with their higher Ag⁺ tolerance, suggesting that EPS may be involved in Ag⁺ detoxification.     

爆炸性气体环境危险区域划分方法改善探讨

本文在对当前爆炸性气体环境的危险区域划分存在的主要问题及其原因分析的基础上,探讨了通过建立爆炸性气体环境危险区域计算机辅助划分平台,提高危险区域划分的可操作性,从而实现爆炸性气体环境危险区域划分方法的改善.探讨了通过运用数值计算方法,基于fluent对爆炸性气体扩散进行研究,对非对称分布场所的危险区域划分提供划分辅助.     

离子色谱分析法用于化学防护服材料渗透性能检测的研究

渗透性能是化学防护服最重要的防护性能指标之一。本文采用PTC200型渗透测试池、蠕动泵、超滤装置和离子色谱分析仪，构建了测试化学防护服渗透性能的装置，并利用该装置对一系列化学防护服面料对浓硫酸和NaOH溶液的渗透性能进行了检测。结果表明，利用该装置可以方便准确地实现服装面料渗透性能测试，是一种具有重要应用价值的检测方法。该方法的开发为规范我们国家化学防护服装及相关产品防护性能检测方式，提高检测结果的准确度和一致性，具有重要的意义。     

A2O氧化沟缺氧区三维流场模拟及结构形式优化

以FLUENT软件为工具，选用三维RNG k-ε紊流数学模型对重庆井口污水厂A²O氧化沟缺氧区内的流场进行模拟，分析了缺氧区内流场分布不均匀及沉泥的原因，提出了水下推进器的合理设置位置与导流墙的合理设置方式，并对优化后的缺氧区进行了模拟计算。通过优化后模拟的结果可见，在相同的功率密度下，缺氧区内的流场得到了较均匀的分布，流速从原来的0.131 m/s提升到0.204 m/s，减少了能量的损失。底部的流速也从原来的0.140 m/s提升到0.226 m/s，有效的防止或减少了沟中的污泥沉积。优化的结果对实际工程的设计也有一定的指导意义。     

我国煤炭生产重心与消费重心演变轨迹研究

利用重心模型,分别测算了1997—2009年我国煤炭生产重心与消费重心的动态变化轨迹,从方向和距离两方面对其进行了对比分析,探讨了煤炭生产重心与消费重心相互偏离的影响。研究表明,我国煤炭生产重心从剧烈不规则运动到剧烈向西南移动,最后平稳向西北转移,煤炭消费重心平缓地呈现出＂西进南移＂的趋势。两者在经度上收敛,纬度上背离,直线距离从1997年的182km增加到2009年的283km;两者间的背离改变了区域煤炭运输格局,加剧了煤炭运输的难度。     

麻质活性炭的制备及其对Cu2＋的吸附研究

以废麻为原料,KOH为活化剂制备粉状活性炭,通过静态吸附实验研究了活性炭对Cu2＋的吸附性能,探讨了溶液起始pH值、活性炭投加量、吸附时间、起始Cu2＋质量浓度等对Cu2＋吸附效果的影响。结果表明,溶液pH和活性炭投加量对吸附效果有较大影响,活性炭对Cu2＋的吸附率在60 min内超过50%,初始浓度在10~50 mg/L时,活性炭对Cu2＋的吸附量与起始浓度近似成正比。采用Langmuir、Freundlich吸附等温式对吸附平衡数据进行了拟合,结果表明吸附等温线符合Frenudlich模型。采用傅立叶红外光谱法（FT-IR）分析了活性炭的表面官能团,分析表明活性炭表面酸性官能团可能是吸附Cu2＋的活性中心。     

市政污泥水热炭化废水组成成分特征

污泥水热炭化处理被认为是极具潜力的污泥安全处置与资源化利用的技术措施之一。为了解废水中碳、氮、磷、钾和重金属含量随水热炭化反应温度和反应时间的变化规律,对市政污泥190℃和260℃水热炭化不同时间（1、6、12、18和24 h）后的废水组成成分进行了研究。结果表明,水热炭化处理后,废水颜色由黑色变成浅黄色;pH由6.40提高到9.14;TOC、COD和BOD5最高分别增加了13 175 mg/L、55 998 O2mg/L和31 723 O2mg/L;氮和钾含量显著提高,但磷含量降低;Cd、Cr含量由未检测到分别增加到0.060 mg/L和2.326 mg/L,As、Pb含量均由0.032 mg/L分别增加到1.408 mg/L和0.590 mg/L,但Cu、Mn及Zn含量降低。比起反应时间,反应温度对废水组成成分的影响更大。