人工湿地处理含重金属废水的研究现状及展望

人工湿地是一种集环境效益、经济效益及社会效益为一体的污水处理技术,因其具有低投入、低能耗、低管理费用、抗冲击力强等优点而成为近年来国内外研究的热点。本文从人工湿地处理各种重金属的去除机理、人工湿地处理含重金属的废水的影响因素方面对近年来人工湿地处理重金属的研究现状予以综述,并对人工湿地处理重金属的研究前景进行了展望。     

潜流型人工湿地污水处理系统及其应用

潜流型人工湿地污水处理系统具有水力负荷和污染负荷大,对BOD,COD,SS,重金属等污染指标去除效果好等优点,是目前国际上较多研究和应用的一种人工湿地处理系统。介绍了潜流型人工湿地污水处理系统的特点、构成、运行效果和应用,指出了潜流型人工湿地系统的应用前景和研究方向。     

人工湿地处理污染河水的研究进展

介绍了不同类型人工湿地系统在处理污染河水方面的研究和应用,分析比较了各类型湿地去除污染物的效果,并探讨了人工湿地处理污染河水的发展趋势.人工湿地以其高效率、低投资、低运行费用等优点而适宜于污染河水的处理,水平潜流湿地、复合垂直流湿地以及组合湿地系统在处理污染河水方面都得到了广泛应用,而且组合湿地系统对TSS、BOD5、COD和TP的去除率要高于复合垂直流湿地和水平潜流湿地.但人工湿地在处理污染河水时对总氮的去除效果相对较差,冬季尤为显著,因此提高人工湿地对总氮的去除率是今后研究的重要内容之一;此外,在人工湿地中基质、植物、微生物对污染河水中低浓度污染物的去除机制及长期去除效果方面,需要进行系统全面的研究.     

柑橘皮吸附剂检测水中重金属离子的研究进展

柑橘皮价格低廉,来源广泛,材料易得,皮中含有丰富的多糖类高分子化合物和木质素,可提供官能团与金属离子结合,去除重金属效果好,可用作制备生物吸附剂。如今工业废水污染严重,重金属污染物在环境中稳定,难去除,生物吸附剂对废水溶液重金属离子具有良好的吸附性能,本文收集了国内外学者利用柑橘皮制作生物吸附剂的资料,综述了改性柑橘皮用于吸附废水中重金属处理的研究进展。     

人工湿地处理城市地表径流的研究进展

人工湿地是独特的土壤-植物-微生物系统,具有耐冲击负荷能力强、投资少、运行费用低、维护管理简便等特点.介绍了城市地表径流的污染研究现状及其来源;总结了人工湿地生态系统的技术特性;评述了人工湿地处理污染物的机理及其在城市地表径流污染去除方面的应用研究;最后,对人工湿地处理城市地表径流污染物的研究趋势进行了分析展望.     

工业废水中重金属离子处理方法与零排放分析概述

介绍了几种高效去除工业废水中重金属离子的方法,即离子交换树脂法、膜处理、EDI,综述了这些方法的发展运用,比较了它们的优缺点,最终发现膜处理在去除重金属离子方面有明显的优势。分析并得出膜处理为核心单元结合其他几种高效的处理技术将是实现工业废水零排放的重要途径,但其膜污染以及浓水处理是影响金属离子零排放的关键,最后展望了未来工业废水重金属离子零排放的发展方向。     

锰氧化物对环境中重金属吸附及影响因素研究进展

综述了近年来国内外锰氧化物对重金属相互作用的研究进展,着重介绍了锰氧化物对重金属离子的去除效果及吸附作用机理;讨论了锰氧化物与重金属离子相互作用时的影响因素;分析总结了目前研究中存在的问题,并探讨了今后的发展方向。     

锰氧化物对环境中重金属吸附及影响因素研究进展

综述了近年来国内外锰氧化物对重金属相互作用的研究进展,着重介绍了锰氧化物对重金属离子的去除效果及吸附作用机理;讨论了锰氧化物与重金属离子相互作用时的影响因素;分析总结了目前研究中存在的问题,并探讨了今后的发展方向。     

改性蒙脱土去除水中重金属离子研究新进展

重金属离子污染具有非降解性、持续存在和累积的性质,影响着人类的生命安全。如何从水中去除重金属离子已经成为治理水污染的核心问题之一,其方法之一就是采用改性蒙脱土进行吸附处理。本文介绍了近年来重金属离子吸附用改性蒙脱土的研究新进展,重点回顾了无机改性蒙脱土、有机改性蒙脱土和无机有机复合改性蒙脱土的改性方法及其对重金属离子的去除能力及机理。提出今后改性蒙脱土研究的主要方向是合成多功能高吸附性的蒙脱土高分子复合微球、蒙脱土高分子凝胶和滤膜材料等,为今后改性蒙脱土作为重金属离子优良吸附剂的研究有一定的指导意义。     

生物法去除水中重金属离子的研究

经济高速发展,社会中化工厂的增多,造成环境中的重金属离子越来越多,一些金属离子会造成严重的环境污染。人们在研究应该采用哪种生物法来去除水中存在的这些重金属离子时,发现传统的去除方法虽有成效但不能从根本上去除,易造成对环境的二次污染。经过多次试验后发现,到目前为止,去除效果最好的方法还是微生物法。微生物法与传统的处理方法相比不仅去除重金属离子的效率高,而且绿色无污染;与应用活性炭的方法相比更加经济实用,应用范围也更加广泛。以微生物去除重金属离子的原理和过程、影响微生物去除重金属离子的因素及微生物去除剂解吸与重复利用为脉络详细介绍这种去除重金属离子的方法。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

基于ATRP法制备的触角状亲水性羟胺树脂的吸硼性能的研究

以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。