超声波辅助杂多酸催化环己醇氧化合成己二酸

在超声波作用下,以磷钨酸为催化剂,用过氧化氢氧化环己醇的方法合成了己二酸。探讨了物料配比、催化剂用量、反应温度、反应时间对己二酸产率的影响。在环己醇用量10.5 mL,30%过氧化氢溶液用量60 mL,催化剂用量0.5 mmol,反应温度75°C,反应时间8 h,己二酸产率达82.1%。最佳条件下的产率比常规方法的产率(60%~70%)高出12%。实验结果表明,这是一种合成己二酸的切实可行的绿色化学工艺。     

磺化炭催化制备环己烯

以活性炭磺化制得的磺化炭为催化剂,环己醇为原料制备环己烯。通过考察反应温度、催化剂用量、催化剂重复使用次数对反应时间与环己烯产率的影响,得出反应的优化条件为:环己醇20 g,反应温度180℃,催化剂用量为环己醇质量的15%。在优化条件下环己烯的产率可达到89%,反应时间约为1 h。磺化炭催化剂重复使用6次后环己烯的产率仍在80%以上。产品经过红外光谱表征。     

杂多酸催化环己醇氧化制备已二酸

以磷钨酸为催化荆,用过氧化氢氧化环己醇的方法合成了已二酸.探讨了物料配比、催化剂用量、反应温度、反应时间对己二酸产率的影响.在环己醇用量10.5 mL,30%过氧化氢溶液用量60mL,催化剂用量0.5 mmol,反应温度80℃,反应时间8 h的条件下,己二酸产率达70.6%.实验结果表明,这是一种合成己二酸的切实可行的绿色化学工艺.     

有机化学实验环己醇制备环己烯的绿色化研究

探索了以无水三氯化铁作催化剂,环己醇脱水制备环己烯的绿色化研究,得出了最佳的反应条件:环己醇20.0 g (0.20 mol),催化剂用量为环己醇物质的量的10%,反应时间为60 min,反应产率可达76%,纯度高达96%。     

杂多酸催化环己醇氧化制备己二酸

以磷钨酸为催化剂，用过氧化氢氧化环己醇的方法合成了己二酸。探讨了物料配比、催化剂用量、反应温度、反应时间对己二酸产率的影响。在环己醇用量10．5mL，30％过氧化氢溶液用量60mL，催化剂用量0.5mmol，反应温度80℃，反应时间8h的条件下，己二酸产率达70．6％。实验结果表明，这是一种合成己二酸的切实可行的绿色化学工艺。     

钼磷酸催化环己醇脱水制备环己烯

研究了钼磷酸催化环己醇脱水制备环己烯的反应,考察了不同催化剂、催化剂用量、反应温度、反应时间、重复使用的催化剂对反应的影响。结果表明,环己醇用量20 g,钼磷酸用量为环己醇的1%,在190~200℃反应50 min时,环己烯收率达83.4%,催化剂可重复使用。     

碘催化环己醇合成环己烯

以碘作为环己醇的脱水剂成功地制备了环己烯,探讨了催化剂用量、反应温度、反应时间对脱水反应的影响。不同催化剂活性比较等问题。结果表明,碘是环己醇脱水制备环己烯的良好催化剂。最佳工艺条件为:催化剂用量为环己醇质量的6.2%,反应温度80～90℃,反应时间4 h,收率68.39%。     

碘催化合成乙酸环己酯的研究

研究了碘催化乙酸与环己醇的酯化反应.考察了物料配比,催化剂用量和反应时间对产品产率的影响.合成乙酸环己酯的最佳条件是:在回流条件下,环己醇用量为0.1 mol,乙酸用量为0.16 mol,即n(乙酸)/n(环己醇)=1.6:1.0,碘的用量为2.0 g,反应时间为120 min.在最佳条件下,乙酸环己酯的产率可达68....     

稀土杂多配离子柱撑水滑石催化合成环己烯

以十四酸根阴离子柱撑ZnAl水滑石为预撑前体,用离子交换法将稀土杂多配离子[Ce(PMoV)2]19-(记为Ce(PMoV)2)插层组装到了水滑石层板间,制备了稀土杂多配离子柱成水滑石催化材料ZnAl-Ce(PMoV)2。对其催化环己醇脱水合成环己烯的反应进行了研究,考察了催化剂用量、反应时间、反应温度和催化剂重复使用等因素对环己烯产率的影响,最佳反应条件为:催化剂用量为环己醇质量的4.0%,反应时间为40min,反应油浴温度为160～170℃,环己烯产率可达86.81%,纯度可达96.7%。反应条件温和,操作简便,催化剂可重复使用,对设备无腐蚀,对环境无污染。     

固体超强酸SO4^2-/ZrO2和S2O8^2-/ZrO2催化合成环己烯

应用固体酸催化剂SO42-/ZrO2和S2O82-/ZrO2作为环己醇的脱水剂,成功地制备了环己烯,并对反应时间、反应温度、催化剂的用量等对脱水反应的影响进行了探讨,实验结果表明,SO42-/ZrO2和S2O82-/ZrO2是环己醇脱水制备环己烯的良好催化剂,并且反应时间短、后处理容易、催化剂用量少、可以重复使用、收率高。脱水反应的最佳工艺条件为：催化剂用量为环己醇质量的6%,反应时间为0.9 h,反应温度为150℃,催化剂用量为环己醇质量的6%。     

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。