预氧化—混凝—复合滤料组合工艺处理含剑水蚤水源水试验研究

经检测,大伙房水库水源水在8～18℃温度范围时含有剑水蚤。本试验采用预氧化—混凝—复合滤料组合工艺达到完全去除剑水蚤的目的,并分别对预氧化、混凝、复合滤料过滤三个水处理工艺单元以及预氧化—混凝—复合滤料组合工艺对剑水蚤的去除效果进行了探究。在PAC投加量为10mg/L、ClO_2投加量为0.2mg/L、采用ΣL/d=1078的无烟煤—石英砂复合滤料的试验条件下,平均出水浊度为0.5NTU,剑水蚤去除率达到100%。在持续4个月的试验过程中,取得了良好的处理效果。试验证明含剑水蚤水源水适合采用预氧化—混凝—复合滤料组合工艺进行降浊除蚤处理。     

羟基磷灰石去除煤矿矿井水氟化物工艺研究及参数优化

针对煤矿矿井水中氟含量超标的问题,采用3种粒径的羟基磷灰石开展连续除氟实验,探讨了羟基磷灰石投加量、进水流量、进水pH、吸附时间及再生次数对矿井水除氟效果的影响。结果发现,羟基磷灰石可用于矿井水深度除氟,其除氟过程为一级反应过程,粒径3μm~5μm的羟基磷灰石除氟效果最好,当羟基磷灰石投加量为100 g、进水流量为0.8 L/h、进水pH=7.53、吸附时间≤60 h时,矿井水出水氟质量浓度能降至≤1 mg/L。     

制备条件对掺镁羟基磷灰石结构及除氟性能的影响

为了提高羟基磷灰石(HAP)滤料的除氟能力,以磷酸、四水硝酸钙和六水硝酸镁为原料,采用化学沉淀法制备一种Mg掺杂羟基磷灰石(Mg-HAP)除氟滤料,研究了制备条件对滤料除氟性能的影响,探究了Mg-HAP滤料的结构与除氟性能之间的关系。结果表明:掺镁量和陈化时间主要影响晶体结构;钙、镁与磷的摩尔比和反应温度主要影响Mg-HAP的纯度;在滤料晶体结构相对保持完整时,滤料的羟基含量越多,滤料的除氟容量越高。在n(Mg)/n(Ca+Mg)为0.10,n(Ca+Mg)/n(P)为1.50,反应温度30℃,搅拌1 h,90℃陈化60 min的优化制备工艺条件下,制备的Mg-HAP滤料样品,Mg在HAP的内部分布均匀;Mg取代羟基磷灰石晶格中的少部分Ca,导致晶面结构发生畸变,晶格缺陷增加,表面吸附能力增强;同时滤料的羟基含量提高,滤料的除氟容量提高。与HAP相比,Mg-HAP除氟容量提高了近4倍。     

反渗透除氟除氨氮技术在饮用水中的应用

反渗透工艺可有选择地将氟离子、氨氮与水分离。水质监测表明,宁夏B市A水厂出水氟化物和氨氮浓度超标,针对现有工艺状况及水质特征,A厂采用了反渗透除氟除氨氮技术进行水质提标改造。为了节省投资及运行成本,采用原水+反渗透膜处理水勾兑方案,近远期勾兑比例分别为3.5∶1和10∶3。主体工艺为多介质过滤器+反渗透装置。长期运行的结果表明,反渗透工艺对氟化物与氨氮的去除效率分别为97%和88%。A厂改造后的出水氟化物浓度、氨氮浓度及其他指标均满足饮用水卫生标准要求,运行成本仅增加0.31元/m³。此工程为国内首次较大规模采用反渗透除氟除氨氮的供水厂,对于以地下水为水源且氟化物、氨氮等特征因子超标的原有水厂提标改扩建、新建水厂除氟、除氨氮具有推广及示范意义。     

连续微滤分离膜和硫酸铝混凝除氟的研究

天津经济技术开发区污水处理厂二级出水的氟离子质量浓度为1.8-3mg／L,研究去除二级出水中氟离子对超标的地下水或其他高氟水的开发、利用具有重要意义,作者主要研究了硫酸铝混凝除氟工艺,并提出和探讨连续微滤膜分离技术(CMF)和铝盐混凝组合除氟的新工艺。CMF系统出水中氟离子质量浓度小于1mg／L,系统出水的SDI值小于3,悬浮物质量浓度低于5mg／L,浊度低于0．5NTU,实验结果令人满意。     

煤-砂双层滤料滤池运行参数优化试验

强化过滤在饮用水常规处理技术中发挥着重要作用。通过对比国内外煤一砂双层滤料滤池设计参数,设计不同配置滤层的试验滤柱进行优化无烟煤一石英砂双层滤料滤池运行参数研究,可为双层滤料滤池设计运行提供一定的技术支持。试验结果表明,上层无烟煤层厚为600 mm、有效粒径为1.0 mm、K_(80)=1.4,下层石英砂层厚为300 mm、有效粒径为0.5 mm、K_(80)≤2.0的配置下滤柱具有较好的过滤性能。当滤速为12 m/h时,滤池出水浊度控制在0.1 NTU以下,2~5μm颗粒数在3 000/mL以下,过滤周期长达26 h,且可以防止浊度和颗粒数穿透滤池。     

高级氧化法深度处理含氟废水的工艺研究

以电子产品洗涤过程中产生的含氟废水为研究对象,针对有机氟化物难降解、生化性差等特点,采用Fenton氧化-钙盐-树脂的耦合工艺处理有机氟废水。Fenton氧化方法可对废水中的有机氟化物进行深度氧化处理,将废水中的有机氟分解为无机氟,氧化后的废水通过"钙盐+树脂"的工艺深度去除废水中的无机氟离子。研究结果表明:Fenton氧化过程中控制pH为4、H_2O_2浓度为12 g/L、Fe~(2+)浓度为12 mmol/L时,氟离子去除效率最高;深度除氟工艺中,钙盐工艺能够将废水中的氟离子浓度降低至12 mg/L,树脂工艺可以进一步将氟离子浓度降低至小于1 mg/L。     

水淬渣处理电厂生活污水的试验研究

通过石英砂和水淬渣单层滤料的对比试验,了解水淬渣的过滤性能.并采用水淬渣-石英砂双层滤料不加药直接过滤技术对电厂生活污水二级出水进行深度处理.试验结果表明:在去除浊度方面,水淬渣和石英砂的过滤性能相差不大;在去除COD方面,水淬渣的过滤性能优于石英砂.滤速为7.5 m/h时,水淬渣-石英砂滤料的平均出水浊度＜3 NTU、COD＜15 mg/L,满足回用标准,出水水质稳定.     

浅层气浮除藻工艺中试试验

该文考察了浅层气浮工艺除藻效能。结果表明浅层气浮工艺除藻的最佳工艺参数:PAC投加量为2~3 mg/L,PAM投加量为0.1 mg/L,溶气罐进口压力为0.30~0.4 MPa,回流比为16%,水力负荷小于7.6 m3/m2·h,进气量大于0.2 m3/min。在此适宜工况下,除藻率大于80%。     

石灰软化-絮凝法处理地下水硬度的试验研究

采用石灰软化-絮凝法处理华南地区某水厂地下水硬度。在实验室进行静态烧杯试验研究,考察石灰投加量、混凝剂投加量、沉淀时间和过滤条件对试验效果的影响。试验结果表明,石灰投加量为180~240 mg/L,PAC投加量为15~30 mg/L,沉淀时间小于30 min,滤料粒径为0.5 mm、滤速为10 m/h时处理效果最佳。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、环氧树脂、不饱和聚酯树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。     

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.     

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.