吉安市农村地区生活污水处理工艺选择

随着农村经济的发展和生活水平的提高,农村生活污水污染问题日趋严重。文章根据吉安市农村地区生活污水的特点,提出了几种适用于农村生活污水处理的工艺,根据当地实际确定了农村污水处理工艺的选择原则。     

豫南地区农村污水处理模式探讨

为推进新农村建设,《国家环境保护"十二五"规划》明确提出,在"十二五"的前三年中,环保部拟投入120亿元用于乡镇农村环境综合治理。探索适合经济相对落后农村地区的污水处理模式势在必行。结合南方农村地区生活污水处理技术研究现状,针对豫南地区地理环境、经济水平等因素,提出了3种适合豫南农村地区的污水处理模式,以期为豫南地区农村分散污水处理系统的建设提供借鉴和参考。     

农村生活污水收集与处理技术现状及进展

在分析农村生活污水特点的基础上,介绍了我国农村现有的生活污水收集模式和国外新的收集技术;结合我国农村的实际情况,提出了农村生活污水处理技术选择原则,概括了我国农村现有的生活污水处理技术方法及研究和应用现状;根据不同处理方法的技术特性和原理,总结归纳了农村生活污水处理组合工艺类型并介绍了典型工程案例。     

一体化处理设备+人工湿地在农村生活污水处理中的优势

随着农村经济的发展,农村污水排放量剧增,加之村民环保意识落后,导致农村水资源破坏严重。在乡村振兴战略的背景下,农村污水处理成了国家发展的重中之重。农村污水处理环境保护工程是五位一体生态文明建设中的重要组成部分。通过分析农村污水处理的特点及存在的问题,指出了一体化处理+人工湿地相结合的污水处理模式在提高污水处理效率上的优势所在,这对我国农村污水处理工程建设发展具有重要意义。     

乡村振兴背景下南四湖流域生活污水治理模式探讨：以微山县为例

文章以微山县为例，探讨乡村振兴背景下南四湖流域农村生活污水的治理模式。根据山东省环保厅的指导方案，本着节省投资、方便运行管理的原则，提出了适合微山县农村污水治理的4种模式：一是市政纳管处理模式；二是村级污水处理站集中处理模式；三是分散收集-集中拉运模式；四是生态治理模式。通过调研和大量数据分析，总结了4种处理模式的使用条件及优缺点，并且重点针对拉运和纳管模式进行了经济分析比较。微山县农村污水的治理经验，可以为南四湖流域地区的农村污水治理项目提供一定的借鉴。     

农村生活污水处理工艺比对和推荐

农村生活污水处理工艺需根据项目区范围内村庄布局、人口规模、地形条件、污水集中收集难易程度、土地资源、周边水面分布、经济条件、种养结构等基本情况进行选择,本文通过对比常用的农村污水处理工艺,总结各工艺的优缺点以及适用条件,对不同情况下的农村污水处理提出推荐工艺。     

农村生活污水处理技术研究进展

农村生活污水是造成农村水环境污染的原因之一,为了改善农村居住环境,必须加强对生活污水的治理。本文分析了我国农村生活污水排放特点、污水处理情况,介绍了几种农村分散污水处理技术,并对其优缺点进行了对比,指出了农村生活污水处理技术未来的发展方向,为我国农村生活污水的治理提供参考。     

发达国家农村污水治理经验及启示

农村在我国社会经济结构中占有重要的地位,党的"十九大"以来我国大力建设美丽乡村.我国农村污水治理的现状复杂,村庄数量多,排水和污水处理设施严重不足,缺乏法规体系和建设管理经验.通过法律法规、建设管理、财政支持、运营模式几方面介绍美国、英国和日本的农村污水治理建设管理先进经验及其存在的问题,为我国农村污水治理建立适合的管理体制、探索科学的建设运营模式、建立有效的监管评价机制等方面提供借鉴.     

农村生活污水处理技术研究进展

分析了我国农村生活污水的特征及处理现状,叙述了人工湿地、蚯蚓生物滤池、稳定塘、土地渗滤、膜生物反应器、生物生态组合工艺这几种农村生活污水处理技术应用现状及研究进展,分析了各处理技术的优缺点。为防止农村水质继续恶化,必须加强农村污水处理,积极探索经济适用的处理技术,分散式、一体化、生态处理技术具有更强的适用性和应用性,可能是今后处理农村生活污水的主要途径。     

人工湿地在农村生活污水处理中的研究及应用现状

人工湿地是一种在农村应用较多的分散生活污水处理技术.本文分析了农村生活污水来源及排放特点,介绍了国内外农村生活污水处理研究现状.从筛选高效基质、组合湿地工艺、系统集成和新型污染物去除等几方面综述了近些年人工湿地在农村生活处理方面的研究及应用现状,最后根据现状从机理研究、工艺设计、优化和运行管理等几方面提出了研究和实践要...     

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.     

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.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.