巯基化对复合填料（ZIF-7@FG）改性环氧涂层的力学及摩擦磨损性能的影响

通过水浴搅拌法分别在氟化石墨烯(FG)表面负载沸石咪唑酯骨架材料(ZIF-7)及其巯基化材料(SH-ZIF-7)以制备复合填料ZIF-7@FG和SH-ZIF-7@FG,并应用于环氧涂层。采用红外光谱仪(FT-IR)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(EDS)对复合填料进行表征,并通过拉伸测试和摩擦磨损试验对改性环氧涂层性能进行了研究。结果表明：利用水浴搅拌法可成功制备ZIF-7@FG和SH-ZIF-7@FG复合填料,改性环氧涂层的力学及摩擦磨损性能明显提升,其中,SH-ZIF-7@FG改性环氧涂层的性能最佳,拉伸强度为26.43 MPa,磨损率为1.8×10^-4mm³/(m·N)。     

环氧树脂复合材料的摩擦学性能研究

综述了环氧树脂复合材料摩擦学性能研究的前沿进展,从无机润滑填料、纳米填料、纤维、有机填料的单一填充以及无机/无机、有机/无机、纤维/填料复合填充等方面阐述了环氧树脂复合材料中填充不同填料改性对其摩擦磨损性能的影响。复合填充多种填料可提高环氧树脂复合材料的耐磨损性能,降低其摩擦系数,使环氧树脂复合材料具有更优异的摩擦学性能。     

无机颗粒填充复合材料摩擦磨损性能研究进展

综述无机粒子填充聚合物复合材料的摩擦磨损性能，从磨损类形、机理、填料的摩擦学作用、摩擦副及工况条件(滑动速度、载荷、温度)的影响等几个方面分析了目前填充改性复合材料摩擦磨损性能的研究进展情况。试验证实，填料与聚合物、聚合物与摩擦副、填料与摩擦副均可能发生化学反应。     

低压高效石墨烯复合涂料的电热性能研究

分别在环氧、环氧改性有机硅、乙烯基树脂3种体系中,以石墨烯为导电填料,研究不同含量的石墨烯对涂料电热性能的影响。结果表明:石墨烯填充在乙烯基树脂中时,发热效率最高,石墨烯复合环氧树脂的涂层附着力最好;石墨烯与环氧改性有机硅复合综合性能最佳。当温度为25℃时,石墨烯含量为3%的环氧改性有机硅涂层在20 V低电压下通电2 min,涂层维持温度为61℃,涂层功率为12.5 W/dm~2,而且涂层物理性能最佳。石墨烯复合环氧改性有机硅树脂的电热涂料能满足安全、便捷、高效的要求。     

填料改性PTFE复合材料的性能

用MG-2000型高速高温摩擦磨损试验机对4组填料填充PTFE复合材料摩擦磨损性能进行研究,并考察相同含量填料由一元增至三元对其摩擦学性能及力学性能的影响。结果表明:单一CF与其混合填料均能提高PTFE复合材料的硬度及压缩强度,降低比重,大幅增强PTFE耐磨性;混合填料改性效果更明显,其中三元填料改性效果最优,且CF/SiC纤维/石墨三元填料改性比CF/GF/石墨三元填料改性效果更佳;石墨、CF与SiC纤维协同效应更显著。     

填充粒子改性聚合物基复合材料摩擦学行为研究进展

综述了无机粒子改性聚合物复合材料的摩擦学方面的研究进展,总结了填充改性后复合材料的摩擦磨损形式及其机理.并且从填料的摩擦学作用,摩擦副以及工矿条件(滑动速度、载荷、温度)等几个侧面分析了目前填充改性复合材料摩擦磨损性能的研究进展情况.最后,文章又指出了聚合物及复合材料的摩擦学研究方向.     

纤维填充PTFE复合材料的摩擦学研究

在聚四氟乙烯（PTFE）中分别填充碳纤维（CF）、玻璃纤维（GF）及这两种纤维不同配比的混杂纤维（HF），制备了具有不同力学性能和摩擦磨损性能的PTFE基复合材料。探讨了填料组成对复合材料硬度和干摩擦条件下摩擦磨损性能的影响，并研究了PTFE基复合材料磨损表面的形貌学。结果表明，适量填充CF和GF均可提高PTFE的摩擦磨损性能，CF比GF效果更为显著；CF和GF的混杂纤维填充PTFE复合材料．表现出一定的协同性，比填充单种纤维，其效果更显著。     

玻璃纤维及石墨增强聚四氟乙烯复合材料摩擦磨损性能的研究

用机械混合、冷压成型和烧结的方法制备了不同质量分数(5%~30%)的玻纤和石墨填充聚四氟乙烯(PTFE)复合材料制品。用M-2000型磨损试验机评价了不同样品在干摩擦下的磨损性能,揭示了填料玻纤和石墨对PTFE复合材料磨损性能的影响,并对磨损机理进行了探讨。用扫描电镜(SEM)对试样磨损形貌进行观察。结果表明:对玻纤进行改性能极大地提高PTFE复合材料的耐磨性能,同时可提高复合材料硬度;玻纤和石墨协同作用,对改善PTFE摩擦磨损性能有比较显著的效果;20%玻纤 10%石墨填充PTFE复合材料有着较好的摩擦磨损性能。     

UHMWPE摩擦磨损性能及其机理的研究进展

介绍了超高相对分子质量聚乙烯(UHMWPE)的摩擦磨损特性及其机理的研究进展，重点介绍了改进摩擦磨损性能方法的研究进展，包括交联改性、填料填充改性、增强改性、共混和加工方法的研究等，并针对这些方法的不足之处和可能的新方法提出了今后的研究方向。     

环氧树脂基复合涂层摩擦磨损性能研究

研究了不同质量分数石墨、碳纤维、纳米ZrO2对环氧树脂(EP)涂层摩擦磨损性能的影响,并用扫描电子显微镜观察了涂层磨损表面形貌并探讨了磨损机理。结果表明:石墨质量分数为20%时复合涂层的磨损率仅为纯EP的7.75%;纳米ZrO2质量分数为4%时复合涂层的磨损率为纯EP的30%;纳米ZrO2与碳纤维以及石墨的协同作用提高了EP的摩擦磨损性能。EP复合涂层的磨损机理以粘着磨损、磨粒磨损以及疲劳磨损为主。     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.