厦门港大气PM2.5中重金属污染特征及健康风险评价

于2020年夏季和秋冬季在厦门港海天码头和嵩屿码头进行大气PM_2.5的采集,并对20种元素污染特征、来源及健康影响进行了分析.结果表明,厦门港大气PM_2.5浓度较低,且两个站点的PM_2.5浓度并无显著性差异,也不存在明显的昼夜差异.地壳元素中以Ca和Si的含量最高,而痕量元素中以Zn和Mn的含量为最高.与标准值相比,重金属元素中只有Cr（Ⅵ）出现超标.受风向和吞吐量季节性变化的影响,部分元素浓度在夏季高于秋冬季. Cu、 Zn、 SO₂和NO₂有较一致的明显昼夜变化,但来自重油燃烧排放的V和Ni并无明显昼夜差异.PMF源解析确定码头PM_2.5的4个污染因子为工业源、船舶排放、交通源和海盐+建筑尘混合源,其中工业源对PM_2.5浓度的贡献率最大（55.2%～59.4%）,远高于船舶排放的贡献率（7.1%～7.7%）.健康风险评估显示,厦门港大气PM_2.5中重金属对人群具有潜在的致癌风险(>1×10^-5...     

武汉典型饮用水水源中典型POPs污染特征与健康风险评估

为了揭示武汉典型饮用水水源中典型持久性有机污染物(POPs)的污染特征与风险水平,采用固相萃取-气相色谱-质谱定性定量分析法,对武汉长江及其支流上18个典型集中式饮用水水源地,共26个采样点水体中多环芳烃(PAHs)、有机氯农药(OCPs)和多氯联苯(PCBs)浓度进行了检测,分析了 POPs的污染水平,并开展健康风险评估.结果表明,26个采样点均有PAHs检出,除苯并[k]荧蒽检出率为88.46％外,其他15种单体检出率均为100.00％,多环芳烃累积ρ(∑PAHs)检出范围为57.04～475.79 ng·L-1,平均值为173.86 ng·L-1.PAHs污染程度总体较低,PAHs主要以中低环芳烃为主,来源于以石油源为主的混合源.共有8种OCPs被检出,(∑OCPs)范围为ND-4.57 ng.L-1,平均值为0.78 ng·L-1,OCPs浓度水平相对较低.共有24种PCBs被检出,ρ(∑PCBs)范围为ND-77.49 ng·L-1,平均值为9.88 ng·L-1,PCBs主要以不易降解的高氯联苯为主,部分点位PCBs浓度超过我国地表水环境质量标准限值,HeptaCBs-180物质需要引起持续关注.健康风险评估结果显示,研究区域内PAHs和PCBs的致癌风险指数均处于10-6～10-4,对人体可能产生潜在的致癌风险;OCPs和PCBs的非致癌风险指数均小于1,不会对人体产生非致癌风险.     

Technology development and cost analysis of multiple pollutant abatement for ultra-low emission coal-fired power plants in China

The implementation of ultra-low emission (ULE) limits (SO₂: 35 mg/m³, NOx: 50 mg/m³, PM: 10 mg/m³) promoted the development of flue gas treatment technologies in China. Pollutant control technology development for Chinese coal-fired power plants was summarized and an analysis of the applicability and cost of pollutant control technologies was conducted. Detailed data were collected from 30 ultra-low emission coal-fired units across China. Based on a cost analysis model, the average unit power generation incremental costs were 0.0144 and 0.0095 CNY/(kW·hr) for SO₂ and NOx control technologies, respectively. The unit power generation incremental cost of twin spray tower technology was 7.2% higher than that of dual-loop spray tower technology. The effect of key parameters on operating cost was analyzed. The unit power generation incremental cost increased because of increments in the electricity price for SO₂ control technology and the price of the reductant in NOx control technology. With high sulfur content or NOx concentration, the unit power generation incremental cost caused by pollutant control increased, whereas the unit pollutant abatement cost decreased. However, the annual operating hours or load increased, thereby leading to a decline in unit power generation incremental cost and unit pollutant abatement cost.     

广州市大气污染特征及其典型环流形势分析

基于2016—2019年空气质量监测数据、地面气象观测数据和中低层天气形势图,分析了广州市大气污染特征及其典型环流形势特征,揭示了不同环流形势与污染物浓度之间的关系.结果表明：(1)近年来广州市随着细颗粒物污染持续改善,空气质量优良率基本维持在80%及以上,但光化学污染问题逐渐凸显,O₃已成为广州市大气污染的主要污染物.(2)广州市大气污染季节变化明显,主要表现为秋、冬季更易出现大气污染,且多为持续性(≥5 d)污染.(3)经过分型和统计,总结出10种典型500 hPa-850 hPa-地面环流型,分别为台风外围-台风外围-台风外围、副高边缘-反气旋环流-变形高压脊、副高边缘-反气旋环流-冷锋前、副高-偏南气流-均压场、副高-偏东气流-均压场、副高-反气旋环流-均压场、副高边缘-反气旋环流-冷高压脊、西风槽槽后-反气旋环流-变性高压脊、副高-偏南气流-冷锋前、副高边缘-偏南气流-冷锋前.个例分析表明,这10种典型环流型可以概述最主要的广州大气污染环流形势,对空气质量预报有一定的指导作用.     

基于DGT技术的黄河上游典型水库沉积物氮磷释放与污染源解析

针对黄河上游河库连通背景下水库的污染源解析不足的问题,基于薄膜梯度扩散和高分辨率孔隙水采样,分析了黄河上游典型水库——沈家河水库的污染特征和扩散通量.结果表明,清水河入库口水质为劣Ⅴ类,沉积物为重度污染状态.各点位上覆水可溶性磷酸盐（SRP）平均值低于孔隙水,表明沉积物SRP因浓度梯度向上扩散.各点位DGT-P与DGT-Fe的相关性及沉积物-水界面浓度差存在空间异质性,1号的沉积物DGT-P释放受Fe-P还原释放主导,2号的表层沉积物DGT-P释放能力较差,3号的表层沉积物DGT-P的释放能力较强,可根据释放机制采取不同治理措施.沉积物-水界面附近1号（4～8 mm）、 2号（8～20 mm）和3号（-8～8 mm）发生NH⁺₄-N浓度减小和NO^-₃-N浓度增加的现象.沉积物释放导致的TP、 TN和NH⁺₄-N负荷增加量分别占总量的100%、 78.3%和56.5%,表明沉积物释放是负荷的主要来源,但是清水河输入对氮的影响不可忽略.结果为黄河上游水库污染源...     

基于循证理论的事故隐患排查治理研究

为更好对企业进行事故隐患排查治理,本文从知识可及性和知识转移等角度,分析导致企业隐患排查治理差异的因素;然后提出基于循证理论的企业隐患排查治理方法并进行实证分析。研究表明:将循证理论引入到企业事故隐患排查治理中具有可行性和有效性。     

再生水补给型城市景观水体中抗生素抗性基因的污染特征——以圆明园为例

由于抗生素抗性基因(Antibiotic Resistance Genes,ARGs)对环境和人类健康存在潜在威胁而逐渐受到人们的重视,高人口密度城市中典型景观水体是ARGs储存库和传播媒介.本研究采用实时荧光定量PCR技术,研究了圆明园不同点位的ARGs污染情况和分布特征.结果表明:园区中ARGs的绝对丰度范围在n.d.(未检出)～1.08×10~9copies·L~(-1)之间;园区进水口目标ARGs的丰度低于末端,表明封闭的水体可能为ARGs的积累提供了理想培养基.在所检测基因中,磺胺类ARGs占主导,ARGs的绝对丰度依次为:sulIIsulImefAtetQtetMermB.磺胺类ARGs与指示微生物粪大肠菌群和大肠杆菌间存在显著相关性,表明指示微生物在ARGs的传播中可能起着关键作用.     

活性炭纤维三维电极电催化降解水中间甲酚——效能及影响因素研究

探讨了以活性炭纤维作为三维粒子电极电氧化降解水中间甲酚的可行性与效果.首先对活性炭纤维的表面形貌,比表面积,孔结构和表面官能团情况进行了表征,发现活性炭纤维（ACFs）以单束纤维的结构交叉排列而成,比表面积较大（>1480m²/g）,另外发现活性炭纤维的表面存在较多官能团种类.结合活性炭纤维表征结果,论文对活性炭纤维三维电极的相关影响因素进行了考察,研究了活性炭纤维种类,活性炭纤维与电极的接触方式以及反应溶液初始pH值对实验结果的影响.结果表明,活性炭纤维表面过多的含氧官能团不利于污染物的快速降解,而三维电极电氧化效果随着pH值的降低而显著增大,不同的电极接触方式对三维电极电氧化效果也有较大影响.     

An efficient way to enhance the total nitrogen removal efficiency of the Anammox process by S0-based short-cut autotrophic denitrification

In order to reduce the amount of NO_3~-–N generated by the Anammox process, and alleviate the competition between denitrification and Anammox for NO_2~-–N in a single reactor, the preference of S~0 for reacting with coexisting NO_2~-–N and NO_3~-–N in the sulfur autotrophic denitrifying(SADN) process and the coupling effect of short-cut SADN and the Anammox process were studied. The results showed that S~0 preferentially reacted with NO_3~-to produce NO_2~-–N, and then reacted with NO_2~-–N when NO_3~-–N was insufficient, which could effectively alleviate the competition between SADN bacteria(SADNB) and Anammox bacteria(An AOB) for NO_2~-–N. After 170 days of operation, coupling between short-cut S~0-SADN and the Anammox process was first successfully achieved. SADNB converted the NO_3~-–N generated by the Anammox process into NO_2~-–N, which was once again available to An AOB. The total nitrogen removal efficiency eventually stabilized at over 95%, and the effluent NO_3~-–N was controlled within 10 mg/L, when high NH_4~+–N wastewater was treated by the Anammox process. Microbial community analysis further showed that Candidatus Brocadia and Thiobacillus were the functional microorganisms for An AOB and SADNB.     

Woody species Rhus chinensis Mill. seedlings tolerance to Pb: Physiological and biochemical response

Screening potential plant species is a crucial consideration in phytoremediation technology. Our previous study demonstrated that Rhus chinensis Mill. seedlings had potentials for phytoremediation of Pb contaminated soil. However, its bioaccumulation and tolerance characteristics remain unclear. Seedling growth, LMWOAs secreted by roots, Pb subcellular distribution and chemical forms, and mineral elements in R. chinensis tissues were evaluated under different Pb concentrations (0, 25, 50, 100, 200 and 400?mg/L) in culture solution at 14?days after planting. R. chinensis did not show visual symptoms of Pb toxicity under lower Pb treatments; however, Pb significantly declined the growth of seedlings under higher Pb treatments. Higher Pb stress also decreased the concentrations of nitrogen in leaves, but increased the concentrations of P and K in roots. Pb stress also decreased Mn concentrations in leaves. A great quantity of Pb was uptake and mostly retained in R. chinensis roots. Nonetheless, R. chinensis can still concentrate 459.3 and 1102.7?mg/kg Pb in leaves and stems, respectively. Most of Pb in R. chinensis tissues was stored in the cell wall with HAc-, HCl-, and NaCl-extractable form. LMWOAs secreted by R. chinensis roots showed a strong positive correlation with Pb concentrations in all plant tissues and with P in roots. Our results suggested that Pb deposited in the cell wall and integration with phosphate or oxalate might be responsible for the tolerance of R. chinensis under Pb stress in short period.