脂肪酸稀土用作PVC热稳定剂的压析和喷霜特性

研究了常见脂肪酸的稀土盐用作ＰＶＣ热稳定剂的压析和喷霜霜特性。结果表明,与常用金属皂（如钙、锌皂）有所不同,硬脂酸稀土不但喷霜小,压析也小;脂肪酸稀土的压析和喷霜具有相似的递变规律;硬脂酸稀土一棕榈酸稀土－肉豆劳动酸衔土～月桂酸稀土〈葵酸稀土〈辛酸稀土。     

PVC用稀土热稳定剂的研究进展

介绍了单一稀土和稀土—铅,稀土—有机锡及稀土—锌等稀土复合热稳定剂的研究现状,探讨了稀土复合热稳定剂的作用机理,并分析了稀土热稳定剂的发展前景。     

PVC新型无毒热稳定剂研究进展

概述了聚氯乙烯的热降解与稳定化机理，着重介绍了稀土稳定剂、有机锑稳定剂、钙／锌稳定剂、水滑石稳定剂等热稳定剂的特点、作用机理及其发展趋势。     

聚氯乙烯无毒热稳定剂的研究进展

概述了聚氯乙烯的热降解机理及热稳定剂的作用机理。重点介绍了稀土稳定剂、有机锑稳定剂、钙/锌稳定剂、水滑石稳定剂等热稳定剂的研究发展情况。     

无铅化稳定剂应用研究进展

本文介绍了无铅化稳定剂的应用现状,重点介绍了无铅化稀土复合稳定剂的作用特性及在UPVC制品中的应用,对稀土化合物的稳定机理进行了探讨。研究表明WWP稀土/钙/锌复合稳定剂无毒、高效、多功能,属新一代绿色环保产品,是具有中国特色的值得大力发展的PVC无铅化热稳定剂。     

环氧脂肪酸稀土的合成及其对PVC热稳定作用的研究

制备了环氧基保留完好的高纯度环氧脂肪酸稀土。研究发现环氧脂肪酸稀土对PVC的热稳定作用类似于硬脂酸稀土，具有长期型热稳定剂的特征，但其热稳定效能明显优于后者，可代替硫醇辛基锡达50%而不降低热稳定性，而硬脂酸稀土只能代替约25%。     

稀土复合稳定剂在PVC加工中的应用

研究了以氯化钕为代表的稀土稳定剂在PVC加工中的应用情况，提出了稀土稳定剂的机理，并用稀土稳定剂生产出合格的U－PVC饮用水管。     

稀土钕(Nd)在聚氯乙烯加工中的热稳定性研究

研究表明,在用钡/锌复合物稳定剂作PVC及PVC/ABS合金的加工过程中,加入少量稀土钕化物,特别是在有能改善其初期着色性的助剂存在下,可大大提高其热稳定性。对用钕 钡/锌复合稳定剂所制备的PVC塑料及PVC/ABS合金来说,当与聚氨基甲酸酯泡沫塑料接触时,其稳定性更是出奇的好。对稀土化合物的稳定机理进行了探讨,认为稳定作用来自3个方面:变价元素、类金属皂作用和稀土络合作用。     

绿色环保PVC热稳定剂的研究进展

概述了聚氯乙烯(PVC)的热降解与稳定化机理,重点介绍了稀土稳定剂、钙/锌稳定剂、水滑石稳定剂及辅助稳定剂的种类与作用、复配的协同作用机理.指出随着人们的环境意识增强和相关的法律法规的执行,PVC的热稳定剂向着无毒、环保的方向发展.     

一步法合成新型稀土复合热稳定剂

研究了一种新型PVC稀土复合热稳定剂的合成工艺以及热稳定效果。用一步法合成了两种PVC稀土复合热稳定剂,讨论了两阶段碱分配比、各阶段反应时间、反应温度以及锌、钙、钡的含量对PVC稀土复合热稳定剂热稳定性的影响。结果表明:合成稀土-锌-钙复合稳定剂工艺条件是70℃、5min、15min、20min,稀土-锌-钡热稳定剂是65℃、15min、20min、5min,静态热稳定测试表明产物中的硬脂酸稀土与硬脂酸金属盐之间有良好的协同作用,两种复合稳定剂的静态稳定时间分别为18.6min、17.5min。     

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.     

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。     

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。