Fe(Ⅱ)、Fe(Ⅲ)和Fe(Ⅵ)活化过硫酸盐氧化降解水中的菲

分别采用Fe(Ⅱ)、Fe(Ⅲ)和Fe(Ⅵ)活化过硫酸盐(PS)氧化降解水中的菲,考察了反应pH、药剂投加量及氧化时间等因素的影响,并对比了不同价态铁活化PS对菲的氧化降解效果.在反应pH为8、n(菲):n(Fe):n(PS)为1:2:2的优化条件下,反应60 min后Fe(Ⅱ)-PS和Fe(Ⅲ)-PS体系对菲的去除率分...     

Application of a Second-Order Kinetic Model to a Complex Melt Polymerization Reaction

A novel copolymer system has been synthesized using methyl hydroquinone diacetate (MHQDA), 1,4 naphthalene dicarboxylic acid (1,4 NDCA), and polybutylene terephthalate (PBT) using the melt polymerization technique. The optimum kinetic parameters pertinent to this system are reported in this study. A simple second-order reaction sequence summarizes catalyzed and uncatalyzed reactions between MHQDA, 1,4 NDCA, and PBT. The kinetic parameters for the copolymerization reaction were determined using a new second-order model. This technique was used to compute the moles of acetic acid generated in the polymerization process. The model was compared to that of the experimentally determined data. Close comparison (percentage error of less than 5%) was obtained between the experimental and theoretical data. The kinetic data support block copolyester formation. The thermal data also supports formation of block polymers.     

Compostability of Poly(lactide): Degradation in an Inert Solid Medium

Commercial poly(lactide) degradation was studied in an inert solid medium simulating compost conditions, with the aim to achieve a complete carbon balance of the polymer degradation. The mineralisation rate at the end of the test was compared to those obtained for poly(lactide) degradation in compost. It was shown that the mineralisation rate after 45 days of degradation was quite lower in inert solid medium than in compost but the standard deviation of data was enhanced. A protocol for both extraction and quantification of the carbon included in the different degradation by-products was proposed and the carbon balance of the polymer degradation was followed during the test with a satisfactory accuracy. The non-degraded PLA material was recovered during the test, hence the evolution of the glass transition temperature and the molecular weight was followed. A two-step degradation mechanism was highlighted in inert solid medium, showing the fundamental role of abiotic reactions for PLA degradation in compost.     

新型聚硅氯化铁铝絮凝剂的制备及性能

以二甲基二氯硅烷为硅源,与氯化铁、氯化铝聚合制得新型的聚硅氯化铁铝（PSFAC）絮凝剂,考察了制备条件及PSFAC对含油废水和药厂废水的絮凝效果。制备PSFAC的最佳条件：nFc：nAl为0．4,nSi：n（Al＋Fe）为0．1,碱化度为2．0,C（Al,Fe）、为0．1mol／L,熟化时间为1-2d。当PSFAC加入量为10mg／L时,对含油废水、药厂废水的浊度去除率分别为84％和86％。PSFAC具有加入量少、沉降速度快、适用的pH范围较宽等优点。     

Reasons for implementing ISO 14001 in Malaysia

Environmental management systems (EMS) have been introduced globally to reduce environmental degradation issues brought about by industrial development. The research discussed in this paper is aimed at identifying the benefits and motivations of the implementation of EMS in compliance with the International Organization for Standardization (ISO) 14001 standard in Malaysian industries by using the pairwise comparison method. Experts in EMS from the Scientific and Industrial Research Institute of Malaysia were invited to participate in the research panel. Based on the experts’ input, data analysis was carried out by using multi‐criteria pairwise comparisons. The findings showed the ranked benefits and motivations of the implementation of the ISO 14001 standard for businesses. The results can indicate to policy‐makers and business advisors how businesses can be encouraged to implement the ISO 14001.     

Hydrological Connectivity Between Headwater Streams and Downstream Waters: How Science Can Inform Policy1

Abstract: In January 2001, the U.S. Supreme Court ruled that the U.S. Army Corps of Engineers exceeded its statutory authority by asserting Clean Water Act (CWA) jurisdiction over non‐navigable, isolated, intrastate waters based solely on their use by migratory birds. The Supreme Court’s majority opinion addressed broader issues of CWA jurisdiction by implying that the CWA intended some “connection” to navigability and that isolated waters need a “significant nexus” to navigable waters to be jurisdictional. Subsequent to this decision (SWANCC), there have been many lawsuits challenging CWA jurisdiction, many of which are focused on headwater, intermittent, and ephemeral streams. To inform the legal and policy debate surrounding this issue, we present information on the geographic distribution of headwater streams and intermittent and ephemeral streams throughout the U.S., summarize major findings from the scientific literature in considering hydrological connectivity between headwater streams and downstream waters, and relate the scientific information presented to policy issues surrounding the scope of waters protected under the CWA. Headwater streams comprise approximately 53% (2,900,000 km) of the total stream length in the U.S., excluding Alaska, and intermittent and ephemeral streams comprise approximately 59% (3,200,000 km) of the total stream length and approximately 50% (1,460,000 km) of the headwater stream length in the U.S., excluding Alaska. Hillslopes, headwater streams, and downstream waters are best described as individual elements of integrated hydrological systems. Hydrological connectivity allows for the exchange of mass, momentum, energy, and organisms longitudinally, laterally, vertically, and temporally between headwater streams and downstream waters. Via hydrological connectivity, headwater, intermittent and ephemeral streams cumulatively contribute to the functional integrity of downstream waters; hydrologically and ecologically, they are a part of the tributary system. As this debate continues, scientific input from multiple fields will be important for policymaking at the federal, state, and local levels and to inform water resource management regardless of the level at which those decisions are being made. Strengthening the interface between science, policy, and public participation is critical if we are going to achieve effective water resource management.     

上海南汇潮滩表层中多环芳烃分布特征及环境意义

利用ＧＣ／ＭＳ分析了上海南汇淤泥质潮滩６，８两月表层沉积物中有机污染物多环芳烃，结果表明，该区在６月和８月８潮滩中ＰＡＨ组化芘，苯并芘及黄蒽具有较高的含量，并且在ＰＡＨ总量中所占比重也产大，在潮滩沉积物中已呈明显富集的趋势。     

Effect of airborne SO_2 on performance of the turnip moth,Agrotis segetum Schiff

SO2 Pollution; rape plant (Brassica chinensis); turnip moth (Agrotis segetum); growth and developmental parameters.     

用智能测硫仪测定水中可吸附有机硫

采用智能测硫仪,使吸附在活性炭上的有机硫在高温空气流中燃烧、分解、定量地转化为二氧化硫,用库仑滴定法测定。水中无机硫化物的干扰用乙酸铜均匀沉淀法去除。     

骆马湖表层水体中32种PPCPs类物质的污染水平、分布特征及风险评估

为评价骆马湖水体中药品和个人护理品(PPCPs)的污染水平、空间分布特征及生态风险,利用高效液相色谱-串联质谱测定了骆马湖水体中22个采样点的32种PPCPs.结果表明,骆马湖表层水体中共检出了23种PPCPs,总浓度范围为892~1 536 ng·L~(-1),其中浓度最高的为诺氟沙星(256~707 ng·L~(-1)),其次是酮洛芬(85~438 ng·L~(-1))、安赛蜜(101~290 ng·L~(-1))及萘普生(1.9~112 ng·L~(-1)).不同采样位点的PPCPs浓度存在一定的空间差异,呈现湖东北部地区较高,西南部地区较低的趋势.房亭河入湖口处PPCPs浓度较高,嶂山闸出湖口处浓度较低.对13种药物类PPCPs生态风险评价结果表明,诺氟沙星RQs为0.26~0.72,对于骆马湖水生生态系统表现为中风险,吉非罗齐在大部分采样点RQs0.01,表现为低风险,其余的化合物RQs0.01未表现出生态环境风险.采用简单叠加模型计算PPCPs的联合毒性风险熵范围为0.29~0.75,整体上看,骆马湖PPCPs对于水生生物表现出中风险.对6种PPCPs的人体健康风险结果表明,RQs均小于1,表明骆马湖PPCPs对人体健康无直接风险.