金属纤维毡在高温除尘上的性能测试与分析

通过对5μm金属纤维毡在不同温度下的拉伸性能和不同过滤风速下的过滤效率进行对比分析,并采用滤料模拟测试装置对滤料进行了VDI结果的测试。结果表明金属纤维毡能达到高温除尘的使用要求,通过提高过滤风速可以有效提高过滤精度,对于粒径大于5μm的粉尘过滤效果可达100%,老化处理后纤维毡过滤周期时间大幅缩短,阻力上升变快,但出口排放浓度降低。     

金属纤维烧结毡表面电镀Ni-P合金工艺及性能研究

利用电镀的方法改变金属纤维烧结毡的性能,在金属纤维烧结毡表面覆盖一层Ni-P合金,并对镀液、镀层及镀后纤维毡过滤性能进行测试。结果表明,Ni-P合金电镀工艺镀液极化良好,性能稳定,电镀光亮范围宽,可以获得外观光泽明亮,表面平整、光滑,没有缺陷的镀层,改善了纤维毡的表面质量。金属纤维烧结毡的透气性随着电镀时间的加长而降低,泡点压力和纤维毡的过滤精度随着电镀时间的加长而升高。     

均匀设计法在滤料过滤性能研究中的应用

以滑石粉作为试验粉尘,以1#、3#中空纤维滤料作为过滤介质,对高效纤维过滤器的性能进行了研究。采用均匀设计法考察了气体含尘浓度、过滤风速、滤料压缩率和过滤时间四个因素对过滤器阻力降和过滤效率的影响。利用DPS数据回归处理方法建立数学模型,确定出试验范围内的优化工艺条件:对于1#滤料,在气体含尘浓度0.68 g/m3,过滤风速0.5 m/s,滤料压缩率16.7%,过滤时间10.3 min时,阻力降为172 Pa,过滤效率为99.993%;对于3#滤料,在气体含尘浓度0.5 g/m3,过滤风速0.5 m/s,滤料压缩率15.4%,过滤时间3 min时,阻力降为493 Pa,过滤效率为99.992%。     

烧结金属多孔材料的过滤精度

过滤精度是烧结金属多孔材料的重要性能指标。除烧结金属丝网多孔材料以平均孔径来判定过滤精度之外,烧结金属粉末以及金属纤维多孔材料都采用过滤效率来判定材料的过滤精度。从GB/T6886《烧结不锈钢过滤元件》、GB/T6887《烧结金属过滤元件》、GB/T20100《不锈钢烧结纤维滤毡》以及GB/T25863《烧结金属丝网多孔材料及其元件》标准中的材料技术指标就可以看出各自过滤精度的判定方法。过滤材料液体的过滤效率(过滤精度)已形成相应的国际标准和国家标准。气体过滤效率(过滤精度)的检测影响因素多,目前没有形成统一标准。从相关资料得到烧结金属多孔材料的液体与气体过滤精度有一定的比对关系。     

金属纤维烧结毡厚度对其过滤比的影响

金属纤维烧结毡作为一种深度型过滤材料,由于其特殊的制作工艺,厚度是一项重要的技术指标。针对某型号金属纤维烧结毡的厚度与其过滤比的关系,进行了相关的试验对比及数据结果分析,对过滤材料的选择及设计具有一定的指导意义。     

金属纤维烧结毡过滤材料过滤性能与科学应用

随着污染控制技术的发展及过滤理论的深入研究,金属纤维烧结毡作为新型的过滤材料在化工、化纤、冶金、石化、食品加工、机械设备、环保等行业得到广泛的应用。金属纤维烧结毡过滤材料是采用不锈钢纤维(镍纤维),利用纤维杂乱交织烧结碾压,形成具有无数不规则孔隙通道和一定厚度的载体,用此来拦截液流中的污染物。该材料具有无脱落,高过滤精度,高纳污容量,耐高温,耐高压,耐有机溶剂,可折波,可焊接,可反复清洗等特点。     

金属纤维烧结毡在过滤与分离行业中的应用

随着高新技术的发展与普及,污染控制领域急待开发新的过滤材料。金属纤维烧结毡正可解决目前现有过滤材料过滤性能所久缺的过滤机能。     

金属纤维毡在高温除尘方面的应用

滤料是高温除尘技术的关键部分,本文着重介绍了不同过滤温度下选用金属纤维毡滤料的类别以及耐高温原理,并对金属纤维毡在高温除尘过程中的过滤机理和性能特点做了详细介绍,提出金属纤维毡将会成为高温除尘滤料的优先首选材料之一。     

熔体过滤器在天然气集输过程中的应用

熔体过滤器采用不锈钢金属纤维烧结毡为过滤介质,是一种具有无数不规则孔隙通道和一定厚度的载体。该过滤器具有可在恶劣环境条件下工作,无脱落,高过滤精度,高纳污容量,通流量大,耐高温、高压、耐腐蚀,可重复使用等特性。     

直流电场中不同凝并参数对粉尘粒度分布的影响

以预荷电室和凝并室为实验系统,对电凝并装置的凝并效果进行了研究,分析了凝并室直流电场中不同极配形式、不同峰值电压、不同烟道风速以及不同粉尘初始浓度对粉尘粒度分布的影响。研究结果表明,当粉尘初始质量浓度为1 g/m3、烟道风速为1.4 m/s、凝并室直流电压为30 k V、凝并室极配形式为双芒刺板时,可吸入颗粒物的凝并效果较好。     

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。     

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.     

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.     

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.