我国农村生活污水组合处理技术研究进展

为确保农村水源安全和人民身体健康,农村生活污水治理刻不容缓,针对我国农村生活污水的来源和特点,按照农村生活污水处理技术的作用机理,将其分为生物组合、生态组合、生物-生态组合3类。根据厌氧单元和好氧单元的不同组合工艺,叙述了近年来各类生物组合处理技术的研究进展;介绍了同种生态技术组合工艺和不同生态技术组合工艺的应用状况;归纳了广泛应用于我国农村生活污水处理的生物+人工湿地组合技术和其他生物+生态组合技术。认为在中国农村地区普遍面临资金短缺、能源不足的情况下,采取一次性投资低、能耗低、运行稳定、运行费用低、维护管理方便的组合技术是解决中国农村污水污染问题的主要途径。     

厌氧滤池-人工湿地处理生活污水的实验研究

采用厌氧滤池-人工湿地的组合工艺处理生活污水,研究对COD、NH3-N、TP的去除效果,研究结果表明：厌氧处理工艺采用生活污水做进水,对COD和氨氮的去除率分别达到79.5%和76.1%;人工湿地采用厌氧滤井出水为进水,对COD、氨氮和总磷的去除率达到77.1%;91.8%;93.2%。     

跌水接触氧化-人工湿地技术处理农村污水研究

针我国村镇分散式污水水质、水量的特点并综合考虑经济、技术等存在的问题,设计了单板交替式跌水方式,并将其与传统人工湿地装置组合处理农村污水。本装置由跌水接触氧化单元和人工湿地单元这两个单元组成。采用生物-生态方法相结合的工艺理念,先通过跌水接触氧化生物法去除有机物以及氮,后通过人工湿地的内部好氧-缺氧-厌氧环境对污水中的有机物及氨氮进行深度去除。     

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。     

农村污水现状及处理技术研究进展

介绍了农村污水状况,农村污水的危害及特点以及农村污水处理模式;阐述了人工湿地、生物生态滤池处理技术、厌氧好氧处理技术、稳定塘、水处理组合工艺、净化槽和土壤渗滤处理技术和污水一体化装置。认为人工湿地、稳定塘、污水处理一体化装置能适合大部分农村污水的处理,但需要进一步改良以提升污水的处理效率和稳定性,其他处理技术耦合效果还有待人们探究。     

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求。     

江门潭江流域农村生活污水分散处理技术工程设计

潭江是江门市人民的母亲河,加强潭江流域农村生活污水治理,对保护潭江地区可持续发展具有重要的意义。文章以潭江流域鹤山市某农村生活污水处理示范项目为例,介绍了"厌氧生物滤池+人工湿地"协同处理农村生活污水工艺流程、工艺设计参数及运行效果。工程应用表明,该工艺处理农村生活污水出水水质稳定,达到了《城镇污水处理厂污染物排放标准》(GB 18918-2002)二级标准,该工艺无人值守管理方便、运营成本低廉,适于潭江流域农村生活污水分散处理推广应用。     

太阳能臭氧生态污水处理

采用生物厌氧／人工湿地／臭氧组合工艺对北京某郊区农村生活污水进行深度处理。同时根据地理位置条件,利用太阳能发电技术为工程提供电源,使出水水质达到《城市污水再生利用景观环境用水水质》（GB／T18921—2002）的标准。该项目具有操作管理简单,运行费用低,无二次污染的特点,处理后的出水全部回用。     

广东某农村生活污水一级A达标处理工艺设计

根据广东某农村生活污水处理工程设计出水水质达《城镇污水处理厂污染物排放标准》(GB18918-2002)一级A标准的要求,选用"酸化水解+MBR+人工湿地"组合处理工艺对该农村生活污水进行处理,该组合工艺对该农村居民区生活污水具有良好的处理效果,出水水质稳定达标。该工程为一级A排放标准条件下小城镇生活污水处理积累了设计经验。     

针对南京市六合区农村生活污水处理案例分析及方案推荐研究

针对江苏省南京市六合区农村生活污水实际情况,推荐了合适六合区各街道(镇)不同农村特点的农村生活污水处理工艺,并以六合区龙袍街道某行政村为例,介绍其主要工艺流程以及运维效果。该行政村主要采用“农户三格化粪池+厌氧处理+人工湿地+生态塘净化”的生态化农村生活污水集中处理组合工艺。同时在系统建成后监测数据表明,该组合工艺出水COD、HN₃-N、TN和TP水质指标优于《农村生活污水处理设施水污染排放标准》(DB32/3462-2020)二级标准。     

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.