陶土负载TiO2/

制备了以陶土为载体的TiO2/SO2-4固体超强酸催化剂,并考察了它对丁酸异戊酯合成反应的催化性能.通过正交试验优化了丁酸异戊酯合成条件催化剂活化温度600℃,催化剂用量12%(以0.15 mol正丁酸为基准),反应物醇酸摩尔比1.21,反应时间1h,酯化率达95.2%.     

陶土负载TiO2/SO2-4催化合成丁酸异戊酯

制备了以陶土为载体的TiO2/SO2-4固体超强酸催化剂,并考察了它对丁酸异戊酯合成反应的催化性能.通过正交试验优化了丁酸异戊酯合成条件:催化剂活化温度600℃,催化剂用量12%(以0.15 mol正丁酸为基准),反应物醇酸摩尔比1.2:1,反应时间1h,酯化率达95.2%.     

固体酸WO_3/TiO_2的制备及其催化合成正丁酸己酯

制备了WO3为活性组分、TiO2为载体的双金属固体酸酯化催化剂WO3/TiO2,用于正丁酸与正己醇酯化合成正丁酸己酯,考察了催化剂中WO3含量、焙烧温度、催化剂用量、n(正己醇)∶n(正丁酸)、反应时间和催化剂重复使用性等因素对酯化率的影响。实验结果表明,催化剂的适宜制备条件是WO350%、500℃焙烧2.0 h。催化合成正丁酸己酯的适宜反应条件为:n(正己醇)∶n(正丁酸)=2.0,催化剂用量2.0 g,环己烷10 mL,反应时间90 m in。在此条件下,酯化率为98.8%,催化剂使用5次后,酯化率仍可达87.6%。     

硫酸氢钠催化合成丁酸戊酯的研究

利用硫酸氢钠作为酯化反应催化剂合成了丁酸戊酯，其最佳反应条件为：催化剂用量0.2g/0.1mol丁酸，醇酸摩尔比2：1，带水剂10mL,反应时间1.0h，丁酸的酯化率可达99．19％。该催化剂催化效果好，使用量少，酯化率高，环境污染小，价廉易得，极有应用价值。     

固体超强酸树脂催化合成邻苯二甲酸二甲酯的工艺研究

以固体超强酸树脂为催化剂合成了邻苯二甲酸二甲酯,分别对醇酸摩尔比、催化剂用量、反应温度、反应时间进行单因素和正交试验,并通过极差和方差分析对酯化过程中显著影响酯化率的因素进行统计分析。结果表明最佳的合成工艺条件为:醇酸摩尔比4.5、催化剂用量2.5%、反应温度115℃、反应时间160min,在此工艺条件下酯化率可达99.5%。该催化剂具有良好的耐磨性,可重复使用。     

陶土负载TiO2／SO4^2-催化合成丁酸异戊酯

制备了以陶土为载体的TiO2／SO4^2-固体超强酸催化剂，并考察了它对丁酸异戊酯合成反应的催化性能。通过正交试验优化了丁酸异戊酯合成条件：催化剂活化温度600℃，催化剂用量12％(以0．15mol正丁酸为基准)，反应物醇酸摩尔比1．2：1，反应时间1h，酯化率达95.2％。     

活性炭负载磷钨酸催化合成乳酸正戊酯

以磷钨酸/活性涂为催化剂,催化酯化合成乳酸正戊酯。通过正交设计法考察了催化剂用量、醇酸摩尔比、反应时间及带水剂用量等因素对反应的影响。结果表明:在催化剂用量1.8 g、醇酸摩尔比1.5、反应时间2 h和带水剂环己烷5 mL的条件下,乳酸正戊酯的酯化率大于96.2%,并且催化剂可多次使用,活性没有明显下降。     

食用香料丁酸己酯合成研究

以钨硅酸为催化剂,通过丁酸和己醇反应合成了丁酸己酯,探讨了醇酸物质的量比、催化剂用量及反应时间对酯化率的影响.实验结果表明:钨硅酸具有良好的催化活性,在醇酸物质的量比为1.2:1、催化剂用量为0.2g/0.1mol丁酸、带水剂(环己烷)8mL、反应温度112～126℃、反应时间1h时,酯化率可达99.1%.     

碳基固体酸催化剂的制备及催化合成油酸甲酯

以蔗糖和对甲基苯磺酸混合物为原料,采用水热法一步合成了碳基固体酸催化剂,用于催化油酸和甲醇酯化合成油酸甲酯。考察了催化剂用量、原料配比、反应时间及催化剂重复使用性等对酯化率的影响。结果表明,适宜反应条件为:催化剂用量为油酸质量的3.54%,醇酸摩尔比6∶1,反应时间7 h,酯化率可达94.96%。该催化剂尚具有一定的重复使用性。     

d—SBA-15-SO3H介孔分子筛催化合成丁酸异戊酯

采用自制的d-SBA-15-SO3H介孔分子筛为催化剂,异戊醇与正丁酸反应合成丁酸异戊酯,考察了催化剂用量、醇酸物质的量比、反应温度、反应时间、催化剂重复使用次数及带水剂等因素对酯化率的影响.结果表明该催化剂具有催化活性高,易分离回收,重复使用性良好等优势.最佳反应条件为:正丁酸用量为0.2 mol时,醇酸物质的量比1.8,催化剂用量2.0g,反应温度130℃,反应时间2.0 h,此时酯化率达97.5%.     

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。