长余辉发光材料的硅溶胶表面包覆研究

采用正硅酸乙酯（TEOS）为原料，通过溶胶-凝胶法对铝酸锶型长余辉发光粉颗粒表面包覆氧化硅膜，防止发光粉的水解失效。试验以草酸作催化剂，分别讨论了乙醇、水、催化剂对包膜效果的影响，最终确定硅溶胶制备的工艺条件[n（TEOS）：n（EtOH）：n（H2O）为1：4：8]。经耐水性、激发光谱、发射光谱以及长余辉性能测试，发光粉与SiO2的比为10：4时就可以很好地防止水解，晶体结构不会发生变化，初始亮度为包膜前的95.9％，余辉时间长达12h。     

改进的溶胶-凝胶工艺制备ZrB_2纳米粉体

采用改进的溶胶-凝胶工艺,以ZrOCl2、H3BO3和蔗糖为原料,以柠檬酸（CA）为络合剂,聚乙二醇（PEG）为分散剂,制备出均匀稳定的Zr-B-C体系溶胶,再以氨水为调节剂,实现溶胶向凝胶转化。在1 500℃温度下经碳热还原反应制备出粒径尺寸约为40 nm,类球状ZrB2粉体。采用XRD、SEM等微观分析手段,对制备的纳米粉体进行了相组成与微观形貌分析。实验中研究了改进的溶胶-凝胶中柠檬酸络合-聚合技术对溶胶性能的影响。结果表明：当n（柠檬酸）∶n（Zr离子）为1∶3时,可获得稳定的Zr-B-C体系溶胶;增大n（B）/n（Zr）值,有利于得到纯度较高、且相组成可控的ZrB2纳米粉体;加入质量分数为1.0%的PEG时,粉体的团聚性能得到很大改善。     

溶胶-凝胶法制备二氧化钛凝胶的影响因素分析

研究了用溶胶-凝胶法制备二氧化钛溶胶的过程，以钛酸丁酯为前驱物，无水乙醇为溶剂，分析了不同的反应条件对凝胶时间的影响。通过实验得到了制备透明稳定凝胶的条件为：反应温度在20～40℃范围内；pH值为2—5；反应物的配比为：醇／钛酸丁酯（摩尔比）为10，水／钛酸丁酯（摩尔比）为3～4，冰醋酸／钛酸丁酯（摩尔比）为1。     

工艺因素对非水解溶胶-凝胶法低温合成硅酸锆的影响

以工业纯ZrCl4、Si（OC2H5）4为前驱体，采用无溶剂的非水解溶胶-凝胶法合成了硅酸锆，研究矿化剂种类、矿化剂用量、前驱物配比对硅酸锆合成效果的影响。结果表明：以LiF为矿化剂、前驱物n（Si）：n（Zr）=1．2：1、矿化剂用量n（Li）：n（Si）=0．3：1、煅烧温度为700℃，可制备出合成率高达98．4％的硅酸锆。     

锌离子室温交联聚丙烯酸酯无皂水溶胶的研究

制备了Zn2+/聚丙烯酸酯无皂水溶胶交联乳液,考察了交联剂用量、交联温度对涂膜交联度、耐水性能及力学性能的影响。结果表明:交联乳液的最佳制备温度为60℃,交联反应室温下即进行完全。涂膜的耐水性能于n(—COO-)∶n(Zn2+)=10∶3时达到最大(水中溶胀度减小了86%),交联反应主要发生在胶乳表面—COO-与Zn2+之间。涂膜力学性能在n(—COO-)∶n(Zn2+)=2∶1时最佳(拉伸强度增加了823%),因为随交联剂用量的增加,少量胶乳内部—COO-也参与了交联反应。     

溶胶-凝胶法制备纳米SiO2/环氧树脂杂化材料

采用溶胶凝胶（Sol-Gel）法,以正硅酸乙酯（TEOS）为无机先驱体,γ-甲基丙烯酰氧丙基三甲氧基硅烷（KH-570）为偶联剂,氨水为催化剂,制备了纳米SiO2／环氧树脂杂化材料以有效控制纳米粒子在基体树脂中的分散。考察了共溶剂乙醇对溶胶-凝胶过程的影响,通过力学性能测试研究了TEOS和KH-570用量对杂化材料性能的影响并通过扫描电镜（SEM）对杂化材料的微观结构进行了表征。结果表明：TEOS质量分数为3％,KH-570质量分数为2％时杂化材料拉伸强度和弯曲强度分别提高9％和10％。杂化材料断口形貌有明显的波纹状,表现为韧性断裂。该方法能够实现无机成分和有机环氧树脂在分子级别上的复合,制备出高性能杂化材料。     

ZrO2/SiO2复合溶胶稳定性的实验研究

以硅酸乙酯和氧氯化锆为先驱体，制备了ZrO2／SiO2复合溶胶，重点考察了ZrO2的摩尔含量、添加剂DMF和TEABr、陈化温度对ZrO2／SiO2复合溶胶稳定性的影响。结果表明：氧氯化锆的存在不利于ZrO2／SiO2复合溶胶的稳定，且随着氧氯化锆摩尔百分含量的增加，溶胶易于凝胶；随着陈化温度的升高，凝胶时间变短；DMF能明显延长ZrO2／SiO2复合溶胶的凝胶时间；当0．4〈n（TEABr）／n（TEOS）〈1时，TEABr能提高溶胶的稳定性。     

稳定纳米二氧化钛水溶胶的制备研究

采用胶溶法制备稳定的纳米二氧化钛水溶胶，研究了pH值、肢体浓度、胶溶剂的浓度及制备温度对胶溶效果的影响。用激光粒度仪测定了其水溶胶纳米体系粒度分布，用SEM电镜：分析观察陶瓷镀膜表面形貌，用EDX能谱分析测定了其微观成分。研究结果显示．在T=313K-353K、pH=1．2—2．0、胶涔浓度0．05—0．3mol／L之间、胶溶剂硝酸和盐酸浓度分别为5％和3％的条件下制备的溶胶较分散稳定。     

溶胶-凝胶法制备Li-β-Al2O3纳米粉体

以硝酸锂、硝酸铝和碳酸氢铵为原料,采用溶胶-凝胶法制备了Li-β-Al2O3纳米粉体。研究了pH值、热处理温度和锂铝物质的量比[n（Li）/n（Al）]对制备Li-β-Al2O3纳米粉体的影响。用X射线衍射仪（XRD）、场发射扫描电镜（FE-SEM）和自动电位粒度仪对制备的粉体进行了表征。结果表明,当n（Li）/n（Al）=1∶5（为化学计量比时）,pH值在3.6左右时,可得到稳定透明的凝胶,经1000℃热处理后,产物为纯相的Li-β-Al2O3,FE-SEM结果表明粉体的粒度在100nm以内。     

纳米二氧化锆溶胶对有机硅耐磨涂料性能的影响

以纳米二氧化锆溶胶、去离子水、乙酸、正硅酸甲酯（ TMOS）、甲基三甲氧基硅烷 （MTMS）、苯基三乙氧基硅烷（ PTES）、γ-（2,3-环氧丙氧）丙基三甲氧基硅烷（ KH-560）为原料,采用溶胶-凝胶法合成了系列有机硅树脂;研究了纳米二氧化锆溶胶、催化剂和溶剂等因素对应用于聚甲基丙烯酸甲酯（ PMMA）基材上的有机硅耐磨涂料综合性能的影响。结果表明：不加纳米二氧化锆溶胶制备的树脂,以 1,8-二氮杂环 [5,4,0]十一烯 -7（DBU）为催化剂,每 100 g涂料中用量为 100 mg,以混合溶剂异丙醇 /醋酸丁酯 /乙二醇乙醚 /丙二醇甲醚醋酸酯（质量比 4∶1∶2∶1）为稀释剂,润湿流平剂 BYK-333用量为涂料的 0. 3%,可制备出附着力为 0级,硬度为 5H,耐磨和耐水煮性能优异的有机硅耐磨涂料。纳米二氧化锆溶胶的添加可提高树脂的折射率,但随着溶胶用量的增加,漆膜的交联能力、耐磨性、耐水性、透明性等性能逐渐降低。     

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。