石墨添加对中间相炭微球电化学性能的影响

以煤焦油沥青为原料，采用聚合法制备中间相炭微球。研究了不同天然鳞片石墨添加量在相同热处理条件下得到的中间相炭微球作为锂离子电池炭负极材料的电化学性能。研究结果表明，石墨的添加使中间相炭微球内部结构变的复杂，X衍射显示石墨的添加降低了炭微球的石墨化度和晶形尺寸。随石墨添加量的增加，电池的首次充放电容量和效率有所减小，三次循环后充放电效率趋于一致。     

热处理温度对锂离子电池用中间相炭微球结构及性能的影响

中间相炭微球作为一种重要的锂离子电池的负极材料,其结构直接关系到锂离子电池的充放电性能。以沥青为原料在惰性环境下,进行热缩聚反应,制备出中间相炭微球。采用XRD手段分别对炭化样品的和石墨化样品（热处理温度不同的炭微球）进行结构分析,又通过恒电流仪对他们的充放电性能进行了测试和结果比较。探讨了热处理温度对中间相炭微球结构及其性能的影响。     

炭化温度对中间相炭微球制备高密高强炭材料性能的影响

采用等静压成型工艺,以中间相炭微球为原料制备自烧结炭材料,研究了炭化温度对所制备材料性能的影响。结果表明,炭化温度对样品的性能有较大影响,自烧结炭材料的密度、抗折强度、抗压强度都随炭化温度(500~1 300℃)的升高而增大,分别可达1.75 g/cm~3、83.5 MPa、333 MPa。样品的电阻率随炭化温度的升高而明显降低,且所制得炭材料各向同性度为1.04。     

炭化温度对掺杂改性树脂炭结构及其抗氧化性能的影响

研究了炭化温度对掺杂改性树脂炭结构及其抗氧化性能的影响。借助于X射线衍射仪、红外光谱仪、扫描电子显微镜和差示扫描量热仪对掺杂改性树脂炭化后的炭结构及其抗氧化性能进行了表征。结果表明:在埋炭条件下,炭化温度对掺杂改性树脂炭化后的炭结构有显著影响:随炭化温度升高,掺杂改性树脂炭化后的炭结构逐渐向石墨化碳结构方向演化;当炭化温度为600℃时,掺杂物表面开始有大量碳晶须生成,晶须的直径约为50~100nm,长度约为几百纳米,随炭化温度升高,碳晶须长径比提高,但碳晶须的产量逐渐下降;当炭化温度为1 000℃时,掺杂物表面生成大量的碳微球,碳微球的直径约为100~500nm。与树脂炭相比,掺杂改性树脂炭化后碳产物的氧化峰值温度提高了约80℃。     

溶胶-凝胶法介孔沥青炭微球的制备及电化学性能研究

以水性中间相沥青(AMP)为前驱体,阳离子表面活性剂(CTAB)为结构导向剂,通过控制AMP的凝胶化和自组装过程,采用溶胶-凝胶法来制备介孔沥青炭微球。利用SEM、HRTEM、SAXRD、FT-IR等分析手段,对产物的形貌及结构进行表征,并研究了介孔沥青炭微球的形成机理和电化学性能。结果表明:在制备介孔沥青炭微球的过程中,CTAB与离子化的AMP可通过S+I-静电力作用形成凝胶球,经炭化后得到介孔沥青炭微球。当CTAB/AMP=1.2时(CTAB为2 g),炭化后得到的介孔炭微球之间界面明显,表面光滑,球体粒径为300~500 nm,当增加CTAB胶束在溶液中的浓度时,炭化产物中得到纳米炭棒。所得介孔沥青炭微球C-AMP1.2-800有序度差、石墨化度低,球体为乱层石墨结构,其在50 mV.s-1下的比电容为103.5 F/g。     

蔗糖基炭材料的制备及其电化学性能研究

在蔗糖中按不同比例掺入膨胀石墨（EG）,在800qC和1000℃炭化制得蔗糖基炭材料。通过扫描电子显微镜（SEM）,透射电子显微镜（TEM）,X射线电子衍射（XRD）,对蔗糖基炭材料的表面形态和内部结构进行表征。采用循环伏安（cv）和恒流充放电表征其电化学性能,并分析其储锂机理。电化学实验结果表明：掺入3％质量比的EG在800℃下炭化得到的蔗糖基炭材料具有最优的大电流充放电性能,其在100mA／g的电流密度下,可逆放电容量为210mAh／g,容量保持率为85．5％;在200rnA／g的电流密度下,可逆放电容量为178．6mAh／g,容量保持率为72．5％。     

氮掺杂空心炭球作为锂离子电池负极材料的研究

以聚苯乙烯为模板,聚吡咯为炭前驱体,制备出尺寸均匀的氮掺杂空心炭球(NHCs)。通过N_2吸脱附曲线、X射线光电子能谱、X射线衍射、扫描电子显微镜、透射电子显微镜和循环伏安法等测试方法考察了炭化温度对空心炭球的微观结构与电化学性能的影响。结果表明,制备的空心炭球直径在160 nm左右,氮原子百分含量达到9.69%。0.5 A·g~(-1)的电流密度下,800℃炭化所得空心球经过200次循环可逆容量达到493.4 mA·h·g~(-1),容量保持率为84%;在5 A·g~(-1)的电流密度下,经过1000次循环,可逆容量仍高达265.2 mA·h·g~(-1)。说明所制备的空心球拥有高的可逆容量、良好的倍率性能和长的循环寿命,是一种优异的储锂材料。     

煤抽提物基炭材料的制备及其电化学性能

以某煤抽提物为前驱体,在N_2保护下,分别在600℃,700℃,800℃和900℃炭化制备四种电化学电容器用炭材料,分别记作:FKC600,FKC700,FKC800和FKC900.采用低温N_2吸附法对各炭材料的孔结构进行表征,并通过恒流充放电和循环伏安测试研究其电化学性能.结果表明:随着炭化温度的升高,四种炭材料的比表面积和总孔容逐渐增大,但孔结构总体上发育不完善,FKC600和FKC700的比表面积仅为14 m~2·g~(-1)左右.四种炭材料在3 mo1/L KOH电解液中具有良好的充放电可逆性和典型的双电层电容特性;其体积比电容和面积比电容随炭化温度的升高呈现先增大后减小的趋势,FKC700的体积比电容高达112.4 F·cm~(-3),FKC600和FKC700的面积比电容大于800μF·cm~(-2),远远高于炭材料的理论储能极限.     

树脂包覆对石墨化中间相沥青炭微球电化学性能的影响

以中间相沥青炭微球(SSGMCMB)为核、酚醛树脂(PR)热解炭为壳，采用浸渍一固化一炭化手段制备出树脂热解炭包覆SSGMCMB复合材料，并对其电化学性能进行了研究。通过SEM、XRD、恒电流充放电测试等手段研究了不同树脂包覆量对该复合材料的形态、结构及其电化学行为的影响，结果表明：树脂热解炭对SSGMCMB有较好的包覆作用，保持了SSGMCMB的球形形态，有利于锂离子的嵌入／脱出反应，对其电化学性能有一定的提高，改进了酚醛树脂热解炭有较大电压滞后的问题。     

聚丙烯腈基炭纳米球的制备

采用低浓度水相分散聚合的方法合成了粒径在230 nm～250 nm的聚丙烯腈球,对其依次经过冷冻干燥、氧化及炭化工艺,用扫描电镜对炭化后的样品形貌进行了观察.结果表明,聚丙烯腈球炭化后转化为粒径在170 nm～190 nm之间的炭纳米球.炭纳米球经1 500 ℃,2 300 ℃及2 800 ℃的高温处理后,X射线衍射仪分析表明,在2 300 ℃处理温度以上可以得到石墨化度明显增加的炭纳米球.     

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.     

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.     

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。