重金属污染土壤修复技术研究进展

随着工农业的快速发展,我国面临着严峻的土壤重金属污染。重金属污染土壤修复已经成为当今生态环境领域面临的重要课题,受到广泛关注。立足于国内外重金属污染土壤修复技术的前沿,对土壤重金属污染的主要来源进行了简单介绍,同时详细阐述和分析了重金属污染土壤的主要修复技术,如物理修复技术、化学修复技术、生物修复技术等,针对各种修复技术的特点和缺点,提出了重金属污染土壤修复技术领域的改进和发展方向,为土壤修复技术研究提供借鉴。     

农田土壤重金属污染与修复技术

文章系统阐述了农田土壤重金属污染种类、来源及其污染特点,针对我国农田土壤重金属污染状况,介绍了当前几类主要的重金属污染土壤修复技术,最后,对土壤重金属污染修复技术的发展进行了展望。     

重金属污染土壤修复技术的研究进展

针对土壤重金属污染的特点,文章介绍了几种主要的重金属污染土壤修复技术:物理修复技术、化学修复技术和生物修复技术,分析了不同修复技术的特点及其存在的问题,同时在此基础上,对重金属污染土壤修复技术的未来发展进行了展望,旨在为重金属污染土壤修复技术提供理论依据和科学支持。     

重金属污染的生物修复研究进展

目前,对重金属污染土壤进行生物修复已成为一个世界性的环境问题,引起了人们的高度关注。本文对重金属污染土壤修复技术的进展情况作了简要介绍和述评,重点介绍了植物修复技术和微生物修复技术,为土壤重金属污染的生物修复提供参考。     

微生物联合植物修复土壤重金属研究现状

经济快速发展的今天，重金属对土壤的污染已成为大家关注的焦点。高效、安全、投入低的微生物联合修复方法，是目前修复土壤重金属污染的主要方式。通过归纳总结微生物联合植物的重金属抗性机制，并对其在修复重金属污染土壤方面的应用进行了综述。现阶段对PGPR技术的研究已经较为全面，但是对于内生菌通过辅助植物修复重金属污染土壤的机制尚不明确，但是具备开发的潜力。     

土壤重金属污染修复技术研究进展

本文概述了土壤重金属污染的来源于危害,主要综述了土壤重金属污染修复技术,并探讨了土壤重金属污染修复技术的研究进展。     

矿区土壤重金属污染的化学修复治理研究进展

金属矿区及周边土壤重金属污染已成为严重的环境问题之一。目前,修复重金属污染土壤的方法很多,文章介绍了目前常用的两种化学修复技术,并对金属矿山重金属污染土壤的化学修复指出进一步发展方向。     

重金属污染土壤修复技术研究现状及发展方向

人类的生存与发展离不开土壤,近年来随着工业的快速发展,重金属污染土壤的问题日益显现,不仅造成了生态环境的破坏,还出现了生物富集现象,最终将危及人类自身,因此很有必要对受重金属污染的土壤进行治理。指出了土壤重金属污染的危害和来源,综述了重金属污染土壤修复技术研究现状,当前主要有物理修复技术、化学修复技术、生物修复技术、生物质炭修复技术以及复合修复技术。单一修复技术需要综合考虑其适用性、修复效果、成本、修复时间等,并须对已修复土壤进行长期监测,因此探索其他经济、高效、环保的修复技术或者复合修复技术将是未来重金属污染土壤修复技术的发展方向。     

土壤重金属污染及治理技术

分析了土壤中重金属污染状况,总结了土壤重金属污染主要修复技术,包括物理化学修复、化学修复、生物修复和农业修复四种技术,并对四种修复技术进行了比较,使人们了解不同修复技术的特点及适用条件.对今后重金属主要研究方向进行了展望.     

土壤重金属污染修复技术研究及进展

总结了目前较常用的土壤重金属污染修复技术有物理修复、化学修复和生物修复,了解到不同修复技术的适用性和局限性;详细阐述了零价铁修复技术的发展概况,以及零价铁用于修复土壤重金属污染的可行性和存在的问题,为今后土壤重金属污染修复指明了一个新的方向。     

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.     

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.     

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.     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.