危险废物鉴别体系比较研究

主要从危险废物(HW)定义及名录、危险废物鉴别程序和危险废物危险特性及其鉴别这三个方面将我国危险废物鉴别体系与美国及欧盟进行了比较,分析了我国危险废物界定和鉴别存在的问题,提出了修改建议。     

Estrogenic and dioxin-like compounds in sediment from Zierikzee harbour identified with CALUX assay-directed fractionation combined with one and two dimensional gas chromatography analyses

The identity of compounds responsible for estrogenic and dioxin-like activities in sediment from the harbour of the small town Zierikzee in Zeeland, The Netherlands, was investigated using a bioassay directed fractionation approach with the in vitro estrogen and dioxin responsive reporter gene assays ER- and DR-CALUX. For identification of compounds exhibiting activity in the bioassays, either one or two-dimensional GC in combination with quadrupole (MSD), ion trap (ITD) or time-of-flight mass spectrometric detection (ToF-MS) was used, depending on the biological and chemical characteristics and the complexity of the fractions. The natural estrogenic hormone 17-β-estradiol and its metabolite estrone were identified with GC–ITD as the main contributors to the estrogenic activity. After successive rounds of fractionation, the dioxin-like activity could be explained by the presence of various polycyclic aromatic hydrocarbons identified with GC–MSD and two-dimensional comprehensive GC × GC–ToF-MS. Some estrogenic activity of a relatively non-polar nature remained unidentified.     

Simultaneous determination of gaseous and particulate chlorinated polycyclic aromatic hydrocarbons in emissions from the scorching of polyvinylidene chloride film

An analytical method for the determination of gaseous and particulate chlorinated polycyclic aromatic hydrocarbons (ClPAHs) was investigated. By means of this method, concentrations and isomer profiles of the 27 target ClPAHs could be analyzed. To evaluate the usefulness of the method for analyzing ClPAH emissions, laboratory-scale scorching tests were performed on polyvinylidene chloride (PVDC) plastic wrap over a flame of the gas burner. Only seven of the target ClPAHs were detected, and all compounds detected had 2, 3, or 4 rings. The detected ClPAHs were present in both the particulate phase and the gaseous phase, but they were present at higher concentrations in the gaseous phase than in the particulate phase. Relationships between the number of chlorine substituents on the naphthalene/phenanthrene rings and the overall concentration and the percentage in the particulate phase were also investigated.     

Fate of PM2.5-bound PAHs in Xiangyang, central China during 2018 Chinese spring festival: Influence of fireworks burning and air-mass transport

Variations of levels, possible source and air mass transmission were investigated for 16 USEPA priority-controlled PAHs in PM_2.5 during 2018 Chinese Spring Festival (CSF) in Xiangyang City, central China which is the North-South pollutant airmass transport channel of China. Totally 37 samples were collected. Mass concentrations of Σ₁₆PAHs for the Pre–CSF day (Pre–CSFD), during the CSF day (CSFD) and after the CSF day (Af–CSFD) are 33.78 ± 17.68 ng/m³, 22.98 ± 6.49 ng/m³, and 8.99 ± 4.44 ng/m³, respectively. High resolution samples showed that Σ₁₆PAHs are higher in the morning (06:00–11:00) or afternoon (11:30–16:30), than those in the evening (17:00–22:00) and at night (22:30–05:30), whereas the result is reversed during the CSFD. Fireworks burning can obviously increase the mass concentration of PAHs. Air mass trajectory indicated that Xiangyang is a sink area of pollutants for northwest and southeast, and the sources of the northeast and southwest. The air mass only can be transmitted out through northeast and southwest. It is effective for improvement of air quality in Wuhan and Hunan to control fireworks emission in Henan and local areas. Fireworks burning was an important source for PAHs during CSFD, biomass, coal combustion, and traffic emission were the main sources of PAHs for Pre–CSFD and Af–CSFD periods. The health risk on the CSFD was higher than the acceptable levels, especially during the intensive fireworks burning, the risk value far exceed 1.0 × 10^?4, controlling burning fireworks is required.     

大穗型杂交水稻父本材料的抗旱性筛选与鉴定

培育大穗型品种是我国超级杂交稻主要育种目标之一,但大穗型水稻品种常存在结实率过低或结实不稳定等严重问题,而旱害常成为上述问题产生的直接原因。以21份大穗型水稻父本品种为供试材料,采用盆栽法,从花粉母细胞减数分裂期开始进行连续10 d的干旱处理（控制土壤相对含水量至40%~50%）,研究了结实率和每穗总粒数的变化。结果表明,干旱处理后品种的结实率和每穗总粒数降低,敏感品种降低幅度显著大于强耐旱品种。试验共筛选出8个大穗型强耐旱父本材料,10个耐旱型父本材料,3个敏感型父本材料。其中R527和9 311选的结实率和总粒数在干旱条件下都表现良好。2个耐旱性差异品种的授粉生物特性分析发现,干旱处理后各品种的花药长度、每柱头花粉总数和萌发数及萌发率均降低,强耐旱型品种R527降低幅度较小;而敏感型品种BL006降低幅度较大,花药长度、每柱头花粉萌发数及萌发率对照和处理间存在极显著差异。研究表明,结实率和每穗总粒数可以作为大穗型品种耐旱性筛选与鉴定的联合指标,花药长度和每柱头花粉萌发率可作为重要的参考指标,大穗型水稻品种耐旱性差异与其在干旱条件下雄性配子的形成及其活力密切相关     

嗜铁细菌CAS17的分离鉴定及其对毒死蜱的降解特性研究

采用改良定向培育法,从获得的几株嗜铁细菌菌株中经过驯化筛选,获得1株对毒死蜱有较高降解作用的细菌CAS17.结合其生理生化特性及16S rRNA序列分析,将其鉴定为耐盐短杆菌(Brevibacterium halotolerans).生长特性和毒死蜱降解试验结果表明,该菌株对毒死蜱有较高的耐受性,在毒死蜱浓度达到800 mg·L-1时仍可生长.最适毒死蜱降解浓度为≤100 mg·L-1,降解率可达67%左右,浓度继续升高时降解效果明显降低;最适降解温度为30℃,对高温敏感;对pH值有着较强的适应范围,pH值在5~9之间的降解率波动不大;最适降解时间为48 h,振荡速率为150 r·min-1,接种量为4%;适合其降解的最佳外加碳源为葡萄糖,最佳氮源为酵母粉,最佳无机盐为CaCl2.     

长江三角洲区域表土中多环芳烃的近期分布与来源

采集长江三角洲区域11个地市范围内的243个样点的表层土壤样品,针对29种多环芳烃(polycyclic aromatic hydrocarbons,PAHs)浓度的空间分布模式、组分谱特征以及初步排放源进行分析.结果表明,研究区域内总PAHs浓度范围在21.0~3 578.5 ng·g~(-1),算术均值310.6 ng·g~(-1),标准偏差459.1 ng·g~(-1).区域PAHs浓度表现出较大的空间分布差异.此外,表土PAHs浓度与表土总有机碳分数TOC呈现正相关.研究涉及的11个地市中,表土PAHs浓度的高值主要集中在苏州辖区,可达759.0 ng·g~(-1)±1 132.9 ng·g~(-1);而无锡(565.3 ng·g~(-1)±705.5 ng·g~(-1))、上海(349.4 ng·g~(-1)±220.1 ng·g~(-1))两市表土的PAHs平均含量仅次于苏州.全区域表土中PAHs组分以2~4环的中、低环组分为主,其中低环比例最高.利用特征比值与主成分分析,可初步判断长江三角洲地区表土中PAHs的近期主要排放源为混合源,即工业燃煤和生物质的燃烧过程同时,局部区域还涉及交通尾气排放.     

1株1,2-二氯乙烷降解菌的分离及降解特性研究

从浙江某化工厂污水处理池的活性污泥中筛选分离到1株能以1,2-二氯乙烷(1,2-dichloroethane,1,2-DCA)为唯一碳源和能源生长的菌株T-2,根据菌株的形态特征、生理生化特性及16S rRNA基因序列分析,该菌株被鉴定为Starkeya sp.研究表明,Starkeya sp.T-2生长和降解1,2-DCA较适宜的温度为30℃,较适宜的pH为7.0～8.0;菌株降解1,2-DCA的过程遵循Haldane动力学模型,其最大比生长速率μmax为0.065 h-1,最大比降解速率vmax为0.54 h-1;菌株降解1,2-DCA的耐受浓度为500 mg.L-1,细胞产率系数(以1,2-DCA计)为0.191 mg.mg-1,菌株T-2利用1,2-DCA生长的过程中能同时把1,2-DCA最终矿化为CO2和H2O,矿化率为45%.     

Pollution characteristics, sources and lung cancer risk of atmospheric polycyclic aromatic hydrocarbons in a new urban district of Nanjing, China

This paper focused on the pollution characteristics,sources and lung cancer risk of atmospheric polycyclic aromatic hydrocarbons(PAHs) in a new urban district of Nanjing,China.Gaseous and aerosol PM_(2.5)(particulate matter with aerodynamic diameter smaller than2.5 urn) samples were collected in spring of 2015.Sixteen PAHs were extracted and analyzed after sampling.Firstly,arithmetic mean concentrations of PAHs and BaP_(eq)(benzo[a]pyrene equivalent) were calculated.The mean concentrations of PAHs were 29.26±14.13,18.14±5.37 and 48.47±16.03 ng/m~3 in gas phase,particle phase and both phases,respectively.The mean concentrations of BaP_(eq) were 0.87±0.51,2.71±2.17 and 4.06±2.31 ng/m~3 in gas phase,particle phase and both phases,respectively.Secondly,diagnostic ratios and principal component analysis were adopted to identify the sources of PAHs and the outcomes were the same:traffic exhaust was the predominant source followed by fuel combustion and industrial process.Finally,incremental lung cancer risk(ILCR) induced by whole year inhalation exposure to PAHs for population groups of different age and gender were estimated based on a Monte Carlo simulation.ILCR values caused by particle phase PAHs were greater than those caused by gas phase PAHs.ILCR values for adults were greater than those for other age groups.ILCR values caused by total(gas + particle) PAHs for diverse groups were all greater than the significant level(10~6),indicating high potential lung cancer risk.Sensitivity analysis results showed that cancer slope factor for BaP inhalation exposure and BaP_(eq) concentration had greater impact than body weight and inhalation rate on the ILCR.     

长江安徽段江心洲土壤重金属的分布特征及来源分析

在长江安徽段15个面积较大的江心洲采集表层(0~20 cm)和深层(150~180 cm)土壤样品,研究其重金属元素含量的分布特征和来源.表层土壤中Cd、Hg、Pb、Cu和Zn等元素平均含量分别是深层的2.33、1.67、1.35、1.48和1.43倍.以长江沉积物背景值作为基线值进行的地累积指数评价结果表明,土壤重金属富集程度依次为CdHgCuZnAsPb.不同江心洲之间以及同一江心洲内部土壤重金属含量的差异,主要与江心洲的成因及其发育演变过程有关,近期淤长的部分,土壤重金属元素含量通常比较高.因子分析结果表明,研究区土壤重金属的富集主要与细颗粒物质的粒径效应、含钙矿物对Cd等元素的固定,以及受燃煤影响的大气沉降输入有关.利用因子得分-多元回归法量化了不同来源重金属的贡献,土壤粒度端元对研究区土壤Ni、Cu、Pb、Zn、As、Cd的贡献率均超过70%.