加热辊压复合土工膜的膜-基复合过渡区研究．

提出了膜-基复合过渡区的概念，认为此为复合土工膜中重要的结构形式；复合土工膜的结构和性能直接与膜-基复合过渡区相关。应用电镜、热分析等技术对复合土工膜的微观结构(横截面结构、平面区域结构、纤维与膜材之间的界面、膜材的结晶结构等)进行研究，阐述了在膜-基复合过渡区中具有的“膜包纤维”微结构，认为膜-基复合过渡区是一种非均匀、非连续、带有一定离散和随机性的材料互穿结构；膜材表层存在纤维状凹槽，纤维与膜材间的界面以弱相互作用为主；加热过程和复合作用对膜材的结晶结构有明显影响。     

光纤对土工膜应力影响的数值仿真

光纤土工膜是一种将光纤蛇形连续地布置于传统土工膜的夹层之中获得具有分布式监测功能的防渗材料，内置光纤对土工膜的应力影响显著，光纤土工膜整体强度的变化规律亟待研究。选用数值仿真方法，探讨光纤对土工膜的加筋作用，分析膜内光纤间距的变化对其力学参数的影响。研究表明：复合土工膜上铺设光纤之后，复合土工膜的抗拉强度得到提高，并且内置光纤减小了复合土工膜的变形，同时，结合光纤的温度敏感度，建议光纤问隔为0．6m。     

PVC复合土工膜的研制与应用

本文介绍了土工膜在水力工程中的应用及PVC复合土工膜的结构,制造工艺流程,产品性能和在工程中应用情况。     

土工膜在水利防渗工程中的应用

随着我国科学技术的不断发展,水利工程已经逐渐成为了上级政府关注的重点项目。而土工膜作为一种新型的防渗透材料,在水利工程中应用非常广泛,尤其是在水坝和水提的修筑过程中能够很好地起到防渗透的作用。下面就土工膜在水利防渗工程中的应用进行简单的分析和探讨。     

天津市卫津化工厂专版

聚氯乙烯复合土工膜通过市级鉴定 天津市卫津化工厂根据[天津经科(91)12号文]下达的任务,对聚氯乙烯复合土工膜进行研制及应用,现已完成批量生产,于1992年12月25日通过市级鉴定。经鉴定委员会对资料审查和现场考核认为:聚氯乙烯复合土工膜是一种新型防渗材料。经在东北双辽电厂、唐山、承德的闸坝、太原热电一厂、二厂的灰坝等十几个工程应用研究表明,该产品具有防渗效果可靠,力学性能好,低温柔性好摩擦系数高,布幅宽,施工方便等特点,成为水利、电力工程有效的,很有发展前途的新型防渗材料,有明显的经济效益、社会效益和环境效益。     

复合聚烯烃土工膜的研制

介绍采用挤出片熔融复合的有增强线网的无纺织物土工膜、纺织织物复合土工膜和防老化复合土工膜，研究了膜结构和增强网对机械性能的影响及膜的耐老化性能。结果表明，按拉伸强度一般编织织物复合土工膜＞无纺织物复合土工膜＞土工膜，按伸长率一般土工膜＞无纺织物复合土工膜＞编织织物复合土工膜。无纺织物复合土工膜具有较好的排水性能，可通过增加一个增强线网提高拉伸强度和降低伸长率。在纺丝、拉丝和挤出片材前加防老化母料，可提高土工膜的耐老化性，由测试结果表明，采用该所的防老化ＰＰ，人工加速老化性能达到２００ｈ，拉伸强度保持率７５．５％，３００ｈ达６８．２％，２００ｈ的人工加速老化相当于２年的自然气候曝晒试验。     

全球PVC薄膜市场发展前景广阔

正据业内人士分析,全球土工膜市场发展前景广阔,到2022年,复合年增长率将保持较快增长。汽油、建筑、采矿等产业对废料处理投入的不断增加,将推动土工膜市场的发展。由于土工膜防刺穿、防撕扯和拉伸强度等性能优越,被应用于水池衬垫、水资源处理、填埋、水产养殖和隧道。全球市场根据应用领域、原料、技术和地区对土工膜进行分类。应用领域又分为隧道与民用建设、采矿和废水处理。2014年,采矿业是主要应用领域。预计采矿业中,密封和填埋技术的不断应用将扩大对土工膜的需求。2015年到2022年,由于全球土工合成材料的应用不断增     

防渗膜在磷石膏渣场的应用

对广西鹿寨化肥厂磷石膏渣场建设过程中存在的问题及经验进行了总结,详细介绍了复合土工膜在磷石膏渣场的应用情况及应注意的问题。     

锂离子电池多孔硅基复合负极材料的研究进展

概述了多孔硅基负极材料在锂离子电池中的应用,重点介绍了材料结构和复合方式对其电化学性能的影响;分析了导致其循环性能降低的主要原因,指出控制电池循环过程中硅基材料体积变化、抑制SEI膜的增加是改善硅基负极材料循环性能的重要途径. 对多孔硅基复合负极材料的研究进行了展望,提出在纳米化和复合化的基础上,设计特殊孔道结构、制备多孔的硅/碳复合材料是推进硅基负极材料应用的重要研究方向.     

聚乙烯土工膜中碳黑、氧化诱导时间及灰分之间的影响研究

氧化诱导时间(OIT)和碳黑含量、分散以及灰分均为检测聚乙烯复合土工膜材料的重要指标。对聚乙烯土工膜产品碳黑和OIT进行试验研究,得出了聚乙烯土工膜产品中碳黑与OIT的影响关系:当碳黑分散度在1~2级的范围内,随着碳黑含量的增加,OIT数值也不断增大;而碳黑分散度在1~3级的范围内,此时试样的碳黑粒子分布不均匀,并存在聚集体,碳黑含量和OIT数值没有相关联系。在OIT测试时,当试验恒温温度及气体等条件相同时,在试样质量为14.5~15.5 mg的范围内,得出了试样质量的变化对土工膜材料的OIT值并无线性影响。采用GB/T 13021—2000和GB/T 9345.1—2008两种方法对聚乙烯土工膜产品灰分含量进行测定和比较,结果表明:两种方法所测定的试样中灰分含量存在一定的差异,其中采用GB/T9345.1的方法反映了聚乙烯土工膜真实的灰分含量,并建议修订GB/T 17643时增加灰分含量技术要求及方法。     

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.     

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。