新型微孔薄膜复合过滤介质的研究开发

根据减小孔径和改善接触滤饼侧的过滤介质孔隙结构有利于减轻介质污染的原则，利用凝固涂层的方法开发出一种具有良好防污性能的微孔薄膜复合过滤介质。它是以常规机织滤布为基布，复合一层微孔薄膜而成的。该复合滤材的微孔膜具有良好的弹性和耐酸碱能力，且与基布黏合良好，膜表面平滑且具有可控疏水性。复合滤布的孔径为1．41～9．12μm，孔隙度为59．33％～79．84％。在过滤过程中，悬浮液中固体颗粒难以进入微孔薄膜复合过滤介质的孔隙中，介质的抗污染能力良好，滤液浊度小，过滤速度稳定，且气耗量低。     

新型微孔薄膜及其复合过滤介质基本性能研究

介绍了利用凝固涂层的技术研制出综合性能良好的微孔薄膜复合过滤介质,其中的薄膜具有良好的弹性,能完全匹配基布的各种力学形变。且与基布黏合良好。说明了微孔薄膜的孔径可以人为控制,随不同的制膜条件孔径一般在1．41～9．12μm范围内变化,薄膜的孔隙度最小不低于52％,以及具有良好的耐酸碱能力和可控疏水性;同时,复合过滤介质的抗拉强度主要由基布承担,基布复合微孔薄膜后的经向、纬向断裂强度仅提高1．75％和2．38％,经向、纬向断裂伸长率提高7．14％和6．26％;复合滤布表面平整光滑,其最大静摩擦系数小于常规的机织滤布,且具有较高的透水能力。     

微孔薄复合过滤介质及其过滤行为

针对常规机织过滤介质的缺点，本文研究并开发了一种新型微孔薄膜复合过滤介质，并考查了该过滤介质力学性能及过滤特性。研究结果表明，这种过滤介质具有良好的力学稳定性和化学和惰性，因体颗粒截留率是堵塞程度低，使用寿命长，滤液浊度低，完全可用于气压过滤中。     

微孔薄膜复合过滤介质及其过滤行为

针对常规机织过滤介质的缺点，本文研究并开发了一种新型微孔薄膜复合过滤介质，并考查了该过滤介质的力学性能及过滤特性。研究结果表明，这种过滤介质具有良好的力学稳定性和化学惰性，固体颗粒截留率高而堵塞程度低，使用寿命长，滤液浊度低，完全可用于气压过滤中     

机织滤布的生产与使用

介绍了国外固液分离用机织滤布的生产与使用现状，分析了国外过滤介质孔径，开孔率，透水和透气性能等测定标准，对机织滤布的材料，织造，精整加工技术等的发展趋势进行了讨论了，并着重介绍了目前重点发展的单丝滤布，双层复合滤布和涂膜滤布。     

机织过滤介质的流体透过性研究

引言机织过滤介质,又称机织滤布,是固液分离领域应用最为广泛的一种过滤介质．滤布的透过度和透水速率的高低直接反映这类过滤介质过滤指标的好坏,因此,研究机织过滤介质透过度和透水速率的变化规律及影响因素对实际过滤作业中合理选择机织滤布具有指导意义．1理论分析机织过滤介质内的孔隙可以分为3类：织物内纱线间孔隙、纱线内纤维间孔隙和纤维上的孔隙．研究表明［1],对流体透过过滤介质起作用的孔隙主要是织物内纱线间孔隙和纱线内纤维间孔隙,因此,假设机织过滤介质总的透水速率是流体通过过滤介质内两类孔隙时的透水速率之和,…     

微孔过滤介质的进展

近２０年来用于固液分离的普通过滤介质除用化纤织物几乎取代了天然织物过滤介质外，微孔过滤介质有了突破性进展，相继出现了亲水微孔陶瓷；微孔复合薄膜，以及单丝纤维过滤介质等，本文综合介绍它们的特性及其出现的背景和重要意义。     

编织滤布自身性能对过滤的影响

从滤布的自身性能出发,分析归纳总结了编织滤布的纱线类型、线密度、纤维支数,捻度,编织方法和精整加工对过滤的影响,在此基础上,依据各种性能对过滤性进行了排序。对今后过滤介质的选用以及发展提供了可靠的参考依据。     

高分子微孔精密过滤新技术在脱碳液过滤改造中的应用

化工生产中的过滤分离是常见的操作单元，按照过滤精度等级可分为粗级过滤（〉100μm）、亚精密过滤（100-10μm）、精密过滤（10-1μm）、超精密过滤（1．0—0．1μm）、超滤、纳滤及反渗透（〈0．1μm）。目前粗级过滤与亚精密过滤采用非金属、金属滤布或滤网作过滤介质的间歇或连续过滤机可满足工艺要求；超精密液体过滤采用有机或无机微孔膜也可获得较好解决；但应用最广泛的精密过滤因存在如下问题而成为最薄弱的过滤操作。     

滤布的过滤性能试验研究

以4种常用工业滤布为过滤介质,分别进行了透过空气、清洁水和酞氰蓝染料悬浮液的渗透性试验,测得了滤布的透气阻力、透水阻力和透过悬浮液的过滤介质阻力,并推出了它们之间的关系。通过悬浮液的过滤试验,提出了一种理论预测滤布的颗粒截留能力的方法。     

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.     

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.     

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.     

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。     

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。