钛酸酯改性微纳米水镁石的制备与表征

通过化学键合作用,将异丙基三(二辛基焦磷酸酰氧基)钛酸酯连接到水镁石表面,制备了一种新型的改性水镁石材料。考察了改性剂用量、改性时间、改性温度等条件对材料疏水性能的影响。结果表明,改性剂添加量为3.5%,改性时间为60 min,改性温度为70℃时,所制备材料的疏水性最好。该材料可用于聚氯乙烯(PVC)塑料的填充改性,有效提高塑料的阻燃性能。     

电气石改性研究

为了增强电气石与有机聚合物的相容性和分散性,对电气石进行了表面改性。用甲苯做溶剂,以钛酸酯做改性剂对电气石进行表面改性,得到疏水性电气石粉体;并对改性电气石进行了活化指数、接触角、亲油化度测试,主要研究了球磨时间,改性剂用量,反应时间,反应温度,固液比对电气石改性效果的影响,确定了电气石粉体表面改性的较好的实验条件。     

硼酸酯偶联剂在HDPE/水镁石复合材料中的应用

用自制的硼酸酯偶联剂改性水镁石,然后将改性水镁石添加到高密度聚乙烯(HDPE)中制得HDPE/水镁石复合材料,并对其进行氧指数、力学性能和微观形貌等测试。结果表明:经硼酸酯偶联剂处理的水镁石的活化指数可达49.7%;活化水镁石用量为50%时,HDPE/水镁石复合材料的氧指数达到24.1%,冲击强度由纯HDPE的6.2 kJ/m2提高到7.9 kJ/m2。SEM测试结果表明:改性水镁石与HDPE基体的相容性较好,并具有良好的增韧作用。     

氧化锑/水滑石复合微粉的表面改性研究

采用共沉淀法制备氧化锑/水滑石复合阻燃微粉,用单硬脂酸甘油酯对其进行表面改性,研究了改性剂的用量、改性时间、改性温度对活化指数的影响。结果表明,最佳改性工艺条件为：改性剂用量4%,改性时间40min,改性温度60℃。单硬脂酸甘油酯对阻燃微粉的表面处理属于氢键吸附,表面处理效果理想,氧化锑/水滑石复合阻燃微粉的晶体结构并未因改性受到影响。     

大分子界面改性剂对PA6/水镁石阻燃性能的影响

通过测试氧指数,探讨了自制的大分子界面改性剂对PA6／水镁石阻燃性能的影响,并与偶联剂TC-114进行了对比。结果表明,加入大分子界面改性剂可以明显提高PA6／水镁石的阻燃性能,当大分子界面改性剂的用量为8份,水镁石添加量为40％时,阻燃效果最佳,氧指数高达37％,比用TC-114处理的PA6／水镁石的氧指数有较大提高。     

复合型氢氧化镁阻燃剂的改性研究

采用石灰乳法制备氢氧化镁阻燃剂,对混合碱用量、溶剂总量、水/醇比和反应时间进行考察,并采用三种典型的改性剂———磷酸三苯酯、双咪唑啉、双子磺酸钠对氢氧化镁阻燃剂进行改性。结果表明,Mg（OH）2的最佳制备条件为：氯化镁与混合碱的摩尔比为1∶2.2,溶剂的总量为2 100 mL,水/醇的体积比为4∶1,反应时间为30 min。采用晶须改性剂磷酸三苯酯时,温度在80℃,改性时间4 h,添加量2%（质量百分比）时,活化指数较好;采用双咪唑啉、双子磺酸钠时,温度在40℃,改性时间2 h,添加量4%（质量百分比）时,活化指数较好。     

钛酸酯偶联剂改性纳米MgO的研究

以钛酸酯偶联剂为改性剂,采用超声波分散的方法对纳米氧化镁（MgO）进行了表面改性。研究了偶联剂用量、改性温度、改性时间对纳米MgO表面改性的影响。通过活化指数实验和扫描电镜的方法表征了纳米MgO的改性效果。结果表明：当钛酸酯偶联剂用量为2％（质量分数）,改性温度为50℃,改性时间为60min时,纳米MgO的表面改性效果最好。     

蛇纹石粉体表面改性研究

研究了Span60、硬脂酸、硼酸酯等8种表面活性剂对蛇纹石粉体的改性效果,确定Span60与硼酸酯以1:1复配型表面活性剂(B1S1)作为蛇纹石粉体的改性剂.以活化指数、浊液体积为表征指标,获得了B1S1湿法改性粉体的优化工艺条件:改性剂用量5%、改性温度70 ℃、改性时间30 min.利用SEM观察了粉体改性前后在环己烷中的分散情况.改性粉体红外光谱分析与热分析表明改性剂与粉体表面发生了化学键合与物理吸附,从而使粉体在非极性溶剂中表现出良好的分散性与悬浮稳定性.     

碱式碳酸镁阻燃低密度聚乙烯的性能研究

采用改性剂对碱式碳酸镁进行表面改性,利用X射线衍射、偏光显微镜分析了碱式碳酸镁改性效果.并将改性的碱式碳酸镁添加到低密度聚乙烯( PE-LD)中,研究了碱式碳酸镁阻燃剂对PE-LD性能的影响.利用热重分析法分析了阻燃PE-LD的热稳定性,利用扫描电镜观察了阻燃PE-LD的微观形貌.结果表明,当阻燃剂的添加量为60%时,...     

硬硼钙石的湿法改性及表征

分别以硬脂酸和油酸为改性剂,无水乙醇为溶剂,采用湿化学法对硬硼钙石进行表面改性。考察了改性温度、改性时间、液固比及改性剂用量等因素对硬硼钙石改性效果的影响。采用红外光谱、XRD、热重分析、SEM等手段对改性前后的硬硼钙石进行分析表征。研究结果表明：在硬脂酸用量为5%（质量分数）、改性时间为75 min、改性温度为75 ℃、液固比（mL/g）为2∶1的条件下,改性产物性能最佳,活化指数达到99.45%;在油酸用量为5%（质量分数）、改性时间为50 min、改性温度为60 ℃、液固比（mL/g）为1∶1的条件下,改性硬硼钙石的活化指数达到68.30%。     

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.     

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。     

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。