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1.
微波辐射磷钨酸催化合成环己酮1,2-丙二醇缩酮   总被引:1,自引:0,他引:1  
在微波辐射下,以磷钨酸为催化剂,以环己酮和1,2-丙二醇为原料合成了环己酮1,2-丙二醇缩酮.研究了反应物投料比、微波辐射功率、微波辐射时间、催化剂用量、带水剂用量等因素对产品收率的影响.确定了最佳反应条件为:环己酮0.2 mol,n(环己酮)∶n(1,2-丙二醇)=1∶1.5,催化剂用量为反应物总质量的0.50%,微波辐射功率600 W,辐射时间16 min,带水剂(环己烷)用量15 mL.在此条件下,环己酮1,2-丙二醇缩酮的产率可达82.0%.  相似文献   

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在微波辐射下,以氨基磺酸为催化剂、环己酮和1,2-丙二醇为原料合成环己酮1,2-丙二醇缩酮,研究了反应物摩尔比、微波辐射功率、微波辐射时间、催化剂用量、带水剂用量、反应温度等因素对产品收率的影响。确定最佳反应条件为:环己酮为0.2mol,n(环己酮):n(1,2-丙二醇)=1:1.3,微波辐射功率500W,微波辐射时间20min,催化剂用量为反应物总质量的0.18%,带水剂环己烷用量15mL,反应温度130℃。在此条件下,环己酮1,2-丙二醇缩酮的收率可达77.2%。  相似文献   

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在微波辐射下,以硫酸氢钾为催化剂,不用溶剂,合成了环己酮1,2-丙二醇缩酮。考察了酮醇物质的量比、催化剂用量、微波功率和辐射时间对产品收率的影响。结果表明,硫酸氢钾有着良好的催化活性,在环己酮用量0.2 mol,n(环己酮)∶n(1,2-丙二醇)=1∶1.4,催化剂用量为反应物总质量的1.25%,微波功率450 W,辐射时间10 min条件下,环己酮1,2-丙二醇缩酮收率可达79.2%,催化剂重复使用4次仍保持较高活性。  相似文献   

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活性炭负载柠檬酸催化合成环己酮 1,2-丙二醇缩酮   总被引:1,自引:1,他引:1  
采用活性炭负载柠檬酸催化剂,以环己酮和1,2-丙二醇为原料,环己烷为带水剂合成了环己酮1,2-丙二醇缩酮,考察了原料配比、催化剂用量、反应时间等因素对反应收率的影响。得到较佳工艺条件为:n(环己酮)∶n(1,2-丙二醇)=1∶1.5,带水剂的用量为反应物总体积的35%,催化剂的用量为反应物总质量的3.1%,回流反应2.5 h,产品收率为89.4%。对催化剂的重复使用性进行了考查,实验结果表明:活性炭负载柠檬酸是合成环己酮1,2-丙二醇缩酮的良好催化剂,在优化条件下,催化剂重复使用5次产品收率基本不变。  相似文献   

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以S2O82-/SnO2-SiO2为催化剂,用环己酮1,2-丙二醇合成缩酮.系统地研究了带水剂及其用量、酮醇摩尔比、催化剂用量、反应时间诸因素对产品收率的影响.通过正交实验得出适宜的反应条件为:n (环己酮) :n (1,2-丙二醇)=1∶1.6,催化剂用量为反应物总质量的2.0% ,带水剂环己烷5.0mL,反应时间50min.在上述条件下,缩酮收率可高达91.47% .  相似文献   

6.
磷钨酸掺杂聚苯胺催化合成环己酮1,2-丙二醇缩酮   总被引:4,自引:2,他引:2  
报道了磷钨酸掺杂聚苯胺催化剂H3PW12O40/PAn的制备,通过环己酮和1,2-丙二醇反应合成了环己酮1,2-丙二醇缩酮,探讨了磷钨酸掺杂聚苯胺催化剂对缩酮反应催化活性的影响,并系统研究了原料量比、催化剂用量和反应时间诸因素对产品收率的影响。实验表明,磷钨酸掺杂聚苯胺催化剂是合成环己酮1,2-丙二醇缩酮的良好催化剂,在n(环己酮):n(1,2-丙二醇)=1:1.5 、催化剂用量为反应物料总质量的0.50%、环己烷为带水剂、反应时间60 min的优化条件下,环己酮1,2-丙二醇缩酮的收率可达81.6%。  相似文献   

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以环己酮与1,2-丙二醇为原料,稀土固体超强酸SO24-/TiO2/Ce(Ⅳ)为催化剂,合成了环己酮1,2-丙二醇缩酮,考察了影响反应的因素.结果表明,在n(酮):n(醇)=1:1.5、催化剂用量占反应物总质量的1.7%、带水剂环己烷用量占反应物总质量的30%、反应时间1 h的优化条件下,环己酮1,2-丙二醇缩酮收率可达84.28%.  相似文献   

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以MCM-48分子筛负载磷钨钼杂多酸为多相催化剂,通过环己酮和1,2-丙二醇反应合成环己酮1,2-丙二醇缩酮.采用正交实验法探讨了MCM-48分子筛负载磷钨钼杂多酸对缩酮反应的催化活性,较系统地研究了原料用量、催化剂用量、带水剂用量、反应时间等因素对收率的影响.结果表明MCM-48分子筛负载磷钨钼杂多酸是合成环己酮1,2丙二醇缩酮的良好催化剂,在n(环己酮)n(1,2丙二醇)=11.6,催化剂用量为反应物料总质量的0.2%,环己烷为带水剂,反应时间1.0 h的条件下,环己酮1,2-丙二醇缩酮的收率可达90.7%.  相似文献   

9.
报道了以硅胶负载硅钨酸为催化剂,通过环己酮和1,2-丙二醇反应合成了环己酮1,2-丙二醇缩酮;通过正交实验优选反应条件,研究了反应物料配比、催化剂用量、反应时间等因素对反应的影响。结果表明,在n(环己酮):n(1,2-丙二醇)=1:1.5、催化剂用量为反应物料总质量的1.5%、带水剂环己烷10mL、反应时间45min的优化条件下,环己酮1,2-丙二醇缩酮的收率可达79.0%。  相似文献   

10.
以环己酮与1,2-丙二醇为原料,稀土固体超强酸SO42-/TiO2/Ce(IV)为催化剂,合成了环己酮1,2-丙二醇缩酮,考察了影响反应的因素。结果表明,在n(酮)n∶(醇)=1 1∶.5、催化剂用量占反应物总质量的1.7%、带水剂环己烷用量占反应物总质量的30%、反应时间1h的优化条件下,环己酮1,2-丙二醇缩酮收率可达84.28%。  相似文献   

11.
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.  相似文献   

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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.  相似文献   

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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。  相似文献   

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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.  相似文献   

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Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

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