Extraction of 17β-estradiol in water using non-imprinted polymer submicron particles in membrane filters

17β-Estradiol (E2) is an endocrine disrupting chemical of harm to both animals and human beings at a low concentration level (ng/L). It cannot be completely removed by wastewater treatments, and is often detected in both environment and drinking waters. The purpose of this feasibility study, towards environmental engineering in the field of water analysis and treatment, was to remove E2 by extraction using non-imprinted polymer (NIP) submicron particles. Experimental results showed that 0.5 mg/L of E2 could be completely extracted by adding 10 mg of NIP particles directly into 10 mL of water. However, the extraction efficiency decreased to 64% for 100 mL of water. prefilling the NIP particles inside a membrane filter showed a potential for water treatment of a large volume, requiring no effort to distribute the particles uniformly in the water. High extraction efficiency (80 ± 10)% for E2 was achieved for 100 mL of water. A total mass of 0.29 mg E2 was extracted from 1000 mL of water containing 0.8 mg/L E2 (by using only 10 mg of NIP particles). Both efficiency and mass capacity can be increased, by scaling up the amount of NIP particles, towards environmental engineering applications.     

沉淀法、吹脱法处理高浓度味精废水试验研究

本研究分别采用混凝沉淀法和吹脱法处理高浓度味精废水。试验结果表明 ,用碱式氯化铝和聚丙烯酰胺作为混凝剂和助凝剂处理 ,对废水中氨氮其去除率小于 10 % ;磷酸铵镁沉淀法氨氮去除率最大可达 6 3% ;吹脱法在 p H>9.5、温度 >5 0℃条件下吹脱 6 h后吹脱效率即可达 5 0 %以上 ,吹脱所需费用为 7.36元 / t,而且吹脱过程中 SO42 - 也被大幅度削减 ,因此应用于实际生产是一种较为可行的方法     

不同生长期加拿大蓬挥发油对蚕豆保卫细胞的毒性效应

为探讨入侵植物加拿大蓬(Erigeron canadensis L.)的化感作用机制,以蚕豆(Vicia faba L.)叶下表皮为材料,研究了营养期和生殖期加拿大蓬挥发油各1μL、2μL、3μL、4μL、5μL分别处理保卫细胞10 min、20 min、30 min后产生的毒性效应。结果表明:挥发油处理后保卫细胞大量死亡,核形态发生较大改变;细胞死亡率和核异常率显著上升(p0.05),与处理剂量和时间呈正相关(p0.01);营养期挥发油处理后细胞的死亡率和核异常率总体高于生殖期;加入泛Caspase抑制剂后,细胞死亡率显著降低(p0.05)。研究表明,加拿大蓬挥发油引起的保卫细胞死亡为Caspase依赖性的细胞凋亡,营养期挥发油的化感胁迫效应比生殖期更强。结合GC-MS分析可见,不同生长期加拿大蓬挥发油毒性的差异可能与其化感物质的组成和含量差异有关。     

The great metals boom: A retrospective

The metals boom that ran from 2003 to 2008 represented the most powerful and sustained such boom since the Second World War. As the boom gathered momentum, the notion began to emerge that commodities were at the beginning of a multi-year ‘super cycle’ driven by demand growth in the emerging economies and, in particular, China. The persistence of the boom helped sustain this belief right up to the point when metal prices collapsed in the second half of 2008. Looking back over the period, much of what occurred can be readily explained by the unusual strength of the demand shock and the lagged response of the supplying industry, with prices receiving an additional boost from the activities of commodity investors. There is, however, some evidence to suggest that the combination of downward pressure on the costs of manufactured goods and upward pressure on the costs of mineral commodities which accompanied the boom marked a shift in the terms of trade between these two product groups. This in turn seems to have brought to an end the sustained decline in real terms metal prices that occurred in the years following the boom of the 1970s. In sum, the key structural change taking place may not have been on the demand side of the industry as the super cyclists maintained, but on the supply side.     

种植油麦菜评价多环芳烃污染土壤的农用风险

污染土壤引起的农产品安全问题已不容忽视.为了探讨多环芳烃(polycyclic aromatic hydrocarbons,PAHs)污染土壤农用的安全性,本文通过盆栽实验方法,以某焦化企业周边长期受PAHs污染的农田土壤为研究对象,以广泛种植的油麦菜(Lactuca sativa L.)为农产品代表,利用超声振荡提取和气相色谱-质谱联用仪(GC-MS)分析方法,解析样品中优先控制的16种PAHs的含量,揭示土壤-油麦菜体系中PAHs的迁移转化与富集特征,评估其潜在风险.结果表明,油麦菜地上部分(YS)PAHs的含量(Σ16PAHs)大于地下部分(GS),YS中3～5环PAHs相对含量高,GS中4～6环PAHs含量高. YS对不同PAHs的富集系数均大于GS,YS中蒽(Ant)的富集系数最大(2. 41),荧蒽(Fla)最小(0. 458),GS中苯并[a]芘(Bap)最大(0. 862),Fla最小(0. 130). 16种PAHs从GS到YS的转运系数均大于1. 00.关联性分析表明GS与初始土壤(SS) PAHs拟合优度中等(R~2=0. 71),YS与SS的PAHs拟合优度最大(R~2=1. 0),YS和GS的PAHs拟合优度最小(R~2=0. 39). YS和GS的健康风险值分别是国家食品标准Bap最大风险控制值的11. 8和12. 7倍.表明油麦菜食用的潜在风险较高,焦化企业周边污染土壤农用的安全问题不容忽视.     

The prevalence of heavy metals in Cladophora glomerata L. from Farahabad Region of Caspian Sea – Iran

The presence of toxic heavy metals in the environment is considered as a risk factor for adverse human and environmental health effects. Farahabad Region is a tourist center in the southern coast of Caspian Sea in Mazandaran Province of Iran. Environmental monitoring of this site is important for public health for individuals visiting and residing in this region. Although numerous biomonitoring data are available globally, very few if any apparent investigations have been conducted in this region. In this study, concentration of three heavy metals chromium (Cr), lead (Pb), and cadmium (Cd) was determined for one year in Cladophora glomerata, the predominant macroalga species present in this region. Detection of heavy metals was performed with atomic absorption spectrophotometer using standard methods. Results showed that the range of Cr metal in various algal samples was 29–55 ppm/g dry weight. The levels of Pb in algal samples (Cladophora) ranged from 2 to 8 ppm/g dry weight. The Cd concentrations in C. glomerata biomass ranged from 1.5 to 8.2 ppm/g dry biomass. In view of potential threats of such high metal concentrations in coastal waters and in algal tissues, it is necessary to adopt conservation measures to ensure public health safety.     

孔雀草对镉胁迫的响应及其积累与分布特征

采用营养液培养法研究了不同浓度的Cd(0、0.01、0.05、0.1、0.2、0.3、0.4 mmol·L-1)对孔雀草叶片光合色素和丙二醛含量以及Cd积累量、亚细胞与化学形态分布的影响.结果表明,随着营养液Cd浓度的增加,叶片光合色素含量呈先升后降趋势,丙二醛含量则呈线性递增趋势,高浓度Cd处理(≥0.1 mmol·L-1)对孔雀草产生了显著的胁迫响应.Cd主要贮存于可溶组分中,根系中占50.91%—66.40%,叶片中占39.09%—60.52%;其次为细胞壁,细胞器中的镉比例较低.随着Cd处理浓度的增加,Cd在根系细胞壁中的贮存比例呈增加趋势.液胞区隔化和细胞壁固持是孔雀草应对Cd胁迫的重要耐性机制.根系中的Cd主要以乙醇提取态存在,占27.62%—70.46%,叶片中Cd主要以去离子水提取态和氯化钠提取态存在,两者合计占58.91%—71.09%.叶片中活性态Cd含量显著低于根系,显著降低了地上部Cd的积累,也显著降低了Cd对地上部的胁迫作用.     

多金属富集植物李氏禾根系对铜吸收机理的研究

李氏禾（Leersia hexandra Swartz）是一种多金属富集植物,通过研究其根系吸收铜的途径和方式,有助于解释李氏禾对铜的富集现象,为开发李氏禾修复铜污染土壤的植物修复技术提供科学依据。本文在温室水培条件下,利用钙离子通道抑制剂（LaCl3）和钾离子通道抑制剂（TEA）,研究了李氏禾根系铜吸收与钙、钾离子通道的关系;同时,在研究 ATP 酶抑制剂、解偶联剂和低温作用对铜吸收影响的基础上,探讨了李氏禾根系铜吸收与能量代谢的关系。结果表明,在1 mmol＆#183;L-1钙离子通道抑制剂的作用下,李氏禾根对铜的吸收明显被抑制了（p＜0.05）。处理48 h后,李氏禾根中铜的浓度较对照下降了39.2%。这说明李氏禾根吸收铜与钙离子通道密切相关。在5 mmol＆#183;L-1钾离子通道抑制剂的作用下,李氏禾根对铜的吸收与对照没用显著差异。这表明,李氏禾根系对铜的吸收可能不是通过钾离子通道进行的。ATP酶抑制剂钒酸钠（Na3VO4）显著地抑制李氏禾根对铜的吸收（p＜0.05）。25μmol·L^-1和50μmol·L^-1 Na3VO4处理48 h后,李氏禾根中铜的浓度较对照分别下降了26.2%和31.0%。由此,推测李氏禾根系对铜的吸收是一个消耗能量的过程。该结果与解偶联剂抑制实验结果相一致。在25μmo·L^-1和50μmol·L^-1解偶联剂2,4-二硝基苯酚（DNP）作用下,李氏禾根系中的铜浓度较对照分别下降了25.8%和42.7%。低温处理对李氏禾根吸收铜的抑制作用较解偶联剂和ATP酶抑制剂更为明显。2℃下暴露48 h,李氏禾根中铜的浓度较对照（25℃）下降了60.1%。这进一步证明了,李氏禾根系对铜的吸收存在消耗能量的主动过程。     

Durable goods and long-run electricity demand: Evidence from air conditioner purchase behavior

I estimate a dynamic structural model of demand for air conditioners, the most energy-intensive home appliance in the US. The model explores the links between demand for durable goods and expected changes in key attributes: energy efficiency and price. I incorporate expectations explicitly as a feature of the choice setting, and use parameter estimates from the model to calculate durable good demand elasticities with respect to energy efficiency, electricity price, and price of the durable itself. These estimates fill a large gap in the literature, and also shed light on consumer behavior in this setting. Results indicate that consumers are forward-looking and value the stream of future savings derived from energy efficiency.     

城市污泥及落叶蚯蚓处理最优条件因子实验研究

蚯蚓的环境生态作用具有促进微生物和其他土壤动物活动、消化分解土壤中重金属的功能,并且能够破碎与分解枯落物。通过城市污泥和城市落叶发酵后建立起蚯蚓养殖基床,以赤子爱胜蚓为主体,通过蚯蚓对污泥中重金属的富集作用实现城市污泥无害化,达到城市污泥与落叶资源化的目的。通过设计四因子四水平正交试验探索赤子爱胜蚓处理城市污泥及落叶的最优条件组合。实验结果表明:在落叶添加比例为35%,蚓床湿度为75%,培养温度为14℃,饲养密度为32mg/g时,赤子爱胜蚓对城市污泥和落叶的处理指标达到峰值,蚯蚓床对于污泥中重金属Cu和Zn的富集量分别为274.32μg/箱和420.98μg/箱,处理效果最佳。