石墨烯的特征、制备及应用研究进展北大核心

石墨烯作为碳的一种同素异形体,由于具有独特的结构和优异的力学、电学、热学、比表面积大等性能,成为该领域研究的前沿和热点话题,它可以与金属、金属化合物、碳纳米管等结合,并在超级电容器、燃料电池、传感器、电极材料等许多领域具有广泛的应用前景。本文综述了石墨烯的起源,对石墨烯的多种制备方法作了介绍,就石墨烯最新应用前景进行了阐述,最后对石墨烯今后的研究方向与发展作了展望。     

石墨烯的特征、制备及应用研究进展

石墨烯作为碳的一种同素异形体,由于具有独特的结构和优异的力学、电学、热学、比表面积大等性能,成为该领域研究的前沿和热点话题,它可以与金属、金属化合物、碳纳米管等结合,并在超级电容器、燃料电池、传感器、电极材料等许多领域具有广泛的应用前景。本文综述了石墨烯的起源,对石墨烯的多种制备方法作了介绍,就石墨烯最新应用前景进行了阐述,最后对石墨烯今后的研究方向与发展作了展望。     

石墨烯改性防弹材料研究进展

综述了国内外关于石墨烯改性防弹材料的研究进展,包括石墨烯改性陶瓷复合材料、石墨烯改性芳纶材料、石墨烯改性超高分子量聚乙烯等其它防弹材料,揭示了石墨烯对防弹材料各项性能的良好的改善效果及其在防弹领域的巨大应用潜力,尤其是在制备轻量化、高性能的防弹材料方面具有较好的应用前景.此外,简要介绍了石墨烯薄膜、多层石墨烯片、石墨烯...     

石墨烯材料在锂离子电池中的应用与前景

石墨烯作为一种新型纳米材料,以其特殊的二维单层延伸碳结构、出色的导电性、导热性、韧性及强度等优异性能,在功能材料、能源等多个领域有着广泛的应用前景。其中石墨烯在锂离子电池电极材料的优化改进方面受到了人们的重视,将石墨烯材料用作电极材料或与其他材料的复合能够在一定程度上发挥优势,对电池性能的提升有一定的效果。本文主要介绍石墨烯材料在锂离子电池中的应用及优势发挥,通过对石墨烯结构、性能的分析,简要地分析总结了石墨烯在锂离子电池正极材料、负极材料等方面的应用,从而分析目前石墨烯材料的优势发挥和重点的研究方向,并对石墨烯在锂离子电池领域的应用前景进行一定的展望,为未来石墨烯电池的制备和发展提供参考。     

石墨烯材料在催化剂中应用功能综述

石墨烯和其衍生物(氧化石墨烯、还原氧化石墨烯和掺杂石墨烯等)以独特的物理性质和可调变的表面化学性质在催化领域有巨大的应用潜力.首先简述石墨烯及其衍生物的制备方法和材料特性,接着归纳该材料在催化剂开发与应用中的研究情况,重点阐述石墨烯材料在催化剂中若干功能,包括作为载体负载金属/金属氧化物活性组分或嫁接有机官能团,作为结...     

石墨烯的制备、特性与应用前景

由于具有许多良好的性质,石墨烯在超级电容器、电极材料、传感器、半导体等领域有巨大的潜在发展空间。不过获取品质优良的石墨烯是石墨烯应用的前提,制备功能完好的石墨烯是未来应用的重点。文章论述了石墨烯的特性、制备、应用以及对其应用的展望。     

MXenes材料的制备、应用及其机理综述

MXenes是一种新型二维晶体材料,由过渡金属及碳/氮元素组成,具有与石墨烯类似的结构,在力学性能、抗氧化性、导电性和亲水性等方面表现优异,可广泛应用于多个领域.综述了MXenes的制备方法及形态结构形态,概述了其在电化学、催化、吸附、储氢等领域的应用性能及有关机理,并对MXenes材料的应用前景做出展望.     

钯/石墨烯复合材料的制备及其性能表征

石墨烯常被用于储能器件的电极材料,然而采用化学方法制备的石墨烯其实际应用性能远低于其理论值。有鉴于此,本文提出了利用惰性金属钯纳米材料解决石墨烯实际应用中存在的电导率差和易产生团聚的问题。制备的钯/石墨烯复合材料具有优异的导电性能,比单一石墨烯材料具有更高的电导率,这表明金属钯纳米颗粒显著改善石墨烯片层间的堆叠团聚以及结构缺陷问题。此外,研究了金属钯纳米颗粒对于钯/石墨烯复合电极材料功率密度的影响。     

石墨烯的制备方法及应用研究进展

石墨烯是在室温下能够稳定存在的碳质二维晶体,其非常优秀的导电性能、机械性能、热性能以及光学性质,是纳米材料领域的研究热点之一。讨论了微机械剥离法、外延生长法、氧化还原法、化学气相沉积法等制备石墨烯材料的方法,并对各种方法的优缺点进行分析。同时简述石墨烯的应用进展,并展望了石墨烯的未来发展前景。     

石墨烯的制备及其负载催化剂的应用研究进展

石墨烯是一种具有二维平面结构的新型碳纳米材料,其特殊的单原子层结构使其具有独特的理化性质。石墨烯具有多种形貌和结构,其形貌和结构与优异的物理和化学性质息息相关,因此,有关石墨烯的制备和应用研究已成为研究的前沿和热点之一。综述了石墨烯的制备方法、功能化方法以及在化学领域中的应用。重点阐述石墨烯应用于化学修饰电极、化学电源和催化剂载体以及气体传感器等方面的研究进展,并对石墨烯在相关领域的应用前景作了展望。     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料，介绍了2005—2006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生产量以及各国塑料制品的进出口情况。作为对比，介绍了中国塑料的生产情况。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（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序，对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008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、不饱和聚酯树脂、环氧树脂)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.