Chemical and optical properties of aerosols and their interrelationship in winter in the megacity Shanghai of China

A field campaign on air quality was carried out in Shanghai in winter of 2012. The concentrations of NO, NO₂, NO_x, SO₂, CO, and PM_2.5 increased during haze formation. The average masses of SO₄^2-, NO₃^- and NH₄⁺ were 10.3, 11.7 and 6.7 μg/m³ during the haze episodes, which exceeded the average (9.2, 7.9, and 3.4 μg/m³) of these components in the non-haze days. The mean values for the aerosol scattering coefficient (b_sp), aerosol absorption coefficient (b_ap) and single scattering albedo (SSA) were 288.7, 27.7 and 0.91 Mm^-1, respectively. A bi-peak distribution was observed for the mass concentrations of CO, NO, NO₂, and NO_x. More sulfate was produced during daytime than that in the evening due to photochemical reactions. The mass concentration of NH₄⁺ achieved a small peak at noontime. NO₃^- showed lower concentrations in the afternoon and higher concentrations in the early morning. There were obvious bi-peak diurnal patterns for bsp and bap as well as SSA. bsp and bap showed a positive correlation with PM_2.5 mass concentration. (NH₄)₂SO₄, NH₄NO₃, organic mass, elemental carbon and coarse mass accounted for 21.7%, 19.3%, 31.0%, 9.3% and 12.3% of the total extinction coefficient during non-haze days, and 25.6%, 24.3%, 30.1%, 8.1% and 8.2% during hazy days. Organic matter was the largest contributor to light extinction. The contribution proportions of ammonium sulfate and ammonium nitrate to light extinction were significantly higher during the hazy time than during the non-haze days.     

双信号细胞电化学法检测氯酚类的毒性

以多壁碳纳米管和离子液体复合修饰电极(MWCNTs-IL/GCE)为工作电极,运用线性扫描伏安法(LSV)研究了人乳腺癌(MCF-7)细胞的电化学行为,检测到了2个明显的氧化峰,其氧化峰电位分别为0.725 V和1.038 V.结合4种嘌呤碱基与模型细胞的电化学行为比较与高效液相色谱分析,确定细胞的电化学响应来源分别为细胞质中黄嘌呤与鸟嘌呤、次黄嘌呤与腺嘌呤的电化学氧化.基于2个响应信号峰电流的变化,研究了五氯酚(PCP)、2,4,6-三氯酚(TCP)和2,4-二氯酚(DCP)对MCF-7细胞的毒性效应,根据剂量-效应关系曲线计算半数抑制效应浓度(IC50)值,并与四甲基偶氮唑盐(MTT)比色法进行比较.结果发现,氯酚类污染物对MCF-7细胞活性有明显抑制作用,细胞电化学法与MTT法测得细胞毒性顺序均为:PCPTCPDCP,表明细胞电化学法可以快速、准确地评价氯酚类污染物的细胞毒性.该研究结果可从核苷酸代谢角度为危害化学品的安全无标记、准确客观的毒性评价方法建立提供新思路.     

聚合氯化铝-壳聚糖复合絮凝剂对腐殖酸的絮凝特性研究

研究了聚合氯化铝-壳聚糖(PAC-CTS)絮凝剂的絮凝特性,进行了聚合氯化铝-壳聚糖复合絮凝剂和单独聚合氯化铝对水中溶解态腐殖酸的去除实验。结果表明:复合絮凝剂在投加量为80 mg/L时即可达到与单独聚合氯化铝投加量为150 mg/L时的去除效果,同时前者适应的pH值范围更宽;与投加量和pH值相比,水样浊度和絮凝搅拌速度是影响絮凝效果的次要因素;另外红外光谱分析发现复合絮凝剂中壳聚糖与聚合氯化铝之间存在相互作用。     

典型页岩气油基钻屑的组成分析及危害评价

分别从重庆某两个页岩气井场选取水平井油基钻屑(A)和直井油基钻屑(B)样品,详细分析其基本性质及组成。结果表明:油基钻屑由72.78%~81.34%的灰分、14.14%~26.21%的有机物和1.01%~4.52%的水分组成。灰分来源于钻井液中的无机添加剂和钻头破碎的岩石碎屑,主要成分为CaCO_3、BaSO_4、SiO_2和Fe_2O_3。有机物来源于调制钻井液的基础油和各类有机添加剂,主要成分为烷烃、多环芳烃、苯系物和烯烃。碱性盐、重金属和有机物是油基钻屑中的三类有害物质,且其危害依次增加,若不加以有效处置,将对当地生态环境和人类健康造成持久性破坏。     

关于环境行政执法公示制

各地环境保护部门正根据政府法制部门的要求实施环境行政执法公示制。对环境行政执法公示制的概念、程序等相关问题以及组织实施环境行政执法公示制进行了探讨。     

Policy options to promote Chinese new energy vehicles consumption

Inspired by the green revolution,new energy vehicles(NEVs)provide a fresh,alternative mode of transportation for Chinese consumers mat reduce their reliance on traditional,gasoline/diesel-based cars.However,despite strong government support for NEVs in China,the level of uptake by consumers remains slow.Using Shanghai as a case study,this article provides a much-needed insight into local consumers’motivations to invest in NEVs through a survey of 100 Shanghai residents.Results indicate that current NEV promotion policies do not have a significant impact on the cognitive trade-off of NEV consumption under the"Integrated Consumer Behavior Model,"mainly due to inconvenient charging facilities,technical concerns regarding battery,higher prices,and wait-and-see attitudes regarding the pilot policy environment.Drawing on experiences from Sweden and New Zealand,this research serves to enhance knowledge on consumer attitudes towards NEVs and assist policy makers in developing more effective green consumption promotion campaigns in the future.     

二噁英类的主要形成过程及分析方法

二噁英高度的持久性、强烈的亲合性使其几乎无处不在,并在生物组织中极易积累,从而成为人们所熟悉的环境中毒性最大的有机化合物之一.本文简单地介绍了二噁英类的毒性、主要形成过程及分析方法.     

Parameter Uncertainty Reduction for SWAT Using Grace,Streamflow, and Groundwater Table Data for Lower Missouri River Basin1

Abstract: This study incorporates the newly available Gravity Recovery and Climate Experiment (GRACE) water storage data and water table data from well logs to reduce parameter uncertainty in Soil and Water Assessment Tool (SWAT) calibration using a SUFI2 (sequential uncertainty fitting) framework for the Lower Missouri River Basin. Model evaluations are performed in multiple stages using a multiobjective function consisting of multisite streamflow and GRACE water storage data as well as a groundwater component. Results show that (1) a model calibrated with both streamflow and GRACE data simultaneously can maintain the water balance for the whole basin, but may improperly partition surface flow and base flow. Additional inclusion of the groundwater constraint can significantly improve the model performance in groundwater hydrological processes. In our case, the estimation of specific yield of shallow aquifers has been increased to 10^?2 from previous much underestimated level (<10^?3). (2) The daily streamflow data are needed to confine the parameters related to water flow in channels such as the Manning’s coefficient, which are less sensitive to the monthly simulations. (3) Parameters are nonuniformly sensitive for different goal variables, and thus, proper specification of a prior distribution of parameters may be the key factor for global optimization algorithms to obtain stable and realistic model performance.     

南岭箭竹生物源挥发性有机物排放特征

本研究于2018年9～11月采用动态顶空套袋法采样与热脱附-气相色谱质谱联用(TD-GC-MS)分析技术,获得了南岭箭竹排放的20种生物源挥发性有机物(BVOCs)的排放组成特征与排放速率.结果表明,异戊二烯是南岭箭竹排放的最主要的BVOCs,其排放速率((1.36±0.99)x104μgC/(m2·h))远高于单萜烯...