固体超强酸催化剂改性的研究进展

综述了国内外有关SO42-/MxOy型固体超强酸催化剂在载体、促进剂、贵金属的引入等方面的改性方法。分析了SO42-/MxOy型固体超强酸的催化机理和失活原因。详细说明了载体中引入纳米材料、稀土元素、其他金属元素（Al,V）、交联剂、分子筛等对催化剂活性和稳定性的影响,阐述了通过使用S2O82-代替SO42-、使用WO3、MoO3、PO43等代替SO42-或引入稀土金属离子改变促进剂完成催化剂改性的方法,以及引入贵金属Pt、Pd等在催化剂改性方面的研究进展。最后展望了SO42-/MxOy型固体超强酸催化剂的发展前景。     

氧化铝对固体超强酸催化萘齐聚反应的影响

按不同 Zr/Al将 Al2 O3 引入 SO42 -/Zr O2 中制备固体超强酸催化剂 SO42 -/Zr O2 -Al2 O3 ,并将所得固体超强酸应用到萘齐聚反应中以制备中间相沥青 .用热台偏光显微镜观察了固体超强酸 SO42 -/Zr O2 及 SO42 -/Zr O2 - Al2 O3 在焙烧过程中形态结构变化及晶相转变过程 .研究发现 ,Al2 O3 引入量对固体超强酸 SO42 -/Zr O2 - Al2 O3 晶相转变温度产生影响 ;适量 Al2 O3 的引入使催化剂中 SO42 -分解温度有较大提高 ;催化剂的 TG- DTG曲线也有所变化 .固相超强酸焙烧温度和引入 Al2 O3 比例影响了萘转化率 .红外光谱分析表明 ,两种固体超强酸催化所得萘齐聚物结构基本相同     

SO_4~(2-)/MxOy型固体超强酸改性研究进展

SO42-/MxOy型固体超强酸是一种新兴的绿色催化剂,在有机合成、废水处理等领域有着广泛的应用。简单分析了SO42-/MxOy型固体超强酸失活的原因,综述了近年来SO42-/MxOy型固体超强酸在载体、促进剂以及贵金属的引入等方面的改性方法。详细介绍了载体中引入纳米材料、稀土元素、其他金属元素、交联剂和分子筛等对催化剂活性和稳定性的影响;综述了用S2O82-,稀土离子,其他离子(Ag+,Ni2+,Al3+,Sn4+等),WO3,MoO3,NO3-等代替SO42-作促进剂,以及引入贵金属Pt和Pd改性方面的研究进展;最后展望了固体超强酸催化剂的发展前景。     

SO_4~(2-)/M_xO_y型固体超强酸催化剂的研究进展

概述了SO2-4/MxOy型固体超强酸催化剂的分类、制备方法及表征手段,详细说明了通过促进剂、催化剂载体及引入金属或离子等对SO2-4/ZrO2型固体超强酸改性方面的研究进展,指出目前在SO2-4/MxOy型固体超强酸催化剂研究方面存在的问题,展望了SO2-4/MxOy型固体超强酸催化剂的发展前景。     

SO2-4/MxOy型固体超强酸催化剂的研究进展

概述了SO2-4/Mx Oy 型固体超强酸催化剂的分类、制备方法及表征手段,详细说明了通过促进剂、催化剂载体及引入金属或离子等对SO2-4/ZrO2型固体超强酸改性方面的研究进展,指出目前在SO2-4/Mx Oy 型固体超强酸催化剂研究方面存在的问题,展望了SO2-4/Mx Oy 型固体超强酸催化剂的发展前景。     

SO_4~(2-)/M_xO_y型固体超强酸催化剂改性研究进展

综述了国内外有关SO24-/MxOy型固体超强酸催化剂在载体、促进剂以及贵金属的引入等方面的改性方法。分析了SO24-/MxOy型固体超强酸催化剂的失活原因,详细介绍了载体中引入纳米材料、稀土元素、其他金属元素(Al,Ga等)、交联剂、分子筛等对催化剂活性和稳定性的影响;综述了用S2O28-,稀土离子,其他离子(Ag+,Ni2+,Al3+,Sn4+等),硫酸盐,WO3,MoO3,NO3-等代替SO42-作促进剂,以及引入贵金属Pt和Pd改性方面的研究进展;最后展望了固体超强酸催化剂的发展前景。     

La掺杂对SO_4~(2-)/ZrO_2固体酸催化剂催化性能的影响

采用浸渍法制备SO42-/Zr O2固体酸,并掺杂稀土元素La对SO42-/Zr O2进行改性,制备了一系列固体超强酸催化剂。通过XRD、TEM表征催化剂结构,并通过滴定法测定催化剂酸量,利用正丁醇和柠檬酸的酯化反应评价催化活性。实验表明,600℃煅烧温度下的SO42-/Zr O2和掺杂量4%SO42-/Zr O2-La2O3活性最高,酯化率分别高达88%和96%,且催化剂具有良好的重复使用性。引入稀土元素La可使活性四方相Zr O2更加稳定,有效增加了催化剂的酸总量,提高了催化剂的活性和重复使用性。     

SO42-/ZrO2固体超强酸催化剂下甲醇和对甲苯酚的醚化反应

通过沉淀-浸渍方法制备了SO42-/ZrO2固体超强酸催化剂。并利用该催化剂进行了甲醇和对甲苯酚醚化反应。结果表明,SO42-/ZrO2固体超强酸催化剂用于醚化反应时,具有很好的催化活性。焙烧温度在650℃左右,催化剂活性较高。此醚化反应的适宜条件:催化剂用量为1.5%,反应物摩尔配比为3∶1,反应温度为120℃,反应时间为4h。     

稀土改性固体超强酸催化制备生物柴油的研究

以SO42-/ZrO2为母体,引入稀土元素La、Ce对其进行改性,制备出一系列稀土固体超强酸催化剂,用X射线衍射、红外光谱和BET手段表征了催化剂的物化性能。研究了催化剂合成生物柴油的催化性能,系统考察了n(甲醇):n(脂肪酸甘油三酯)、催化剂用量、反应温度、反应时间等因素对生物柴油产率的影响。结果表明:稀土的引入使活性四方相ZrO2更加稳定;催化剂中形成了固体超强酸结构,且改性后酸强度增大,催化剂活性中心数目增加。SO42-/ZrO2-La2O3的催化活性较高,n(甲醇)∶n(脂肪酸甘油三酯)=10∶1、m(催化剂)∶m(原料油)=4∶100、反应温度250℃、反应时间9 h,此时甲酯的产率可达到73.46%。该催化剂活性较高,重复使用3次后生物柴油产率仍在60%之上。     

SO^2-4／MxOy型固体超强酸催化剂改性研究进展

综述了国内外有关SO2-4/MxOy型固体超强酸催化剂在载体、促进剂以及贵金属的引入等方面的改性方法.分析了SO2-4/MxOy型固体超强酸催化剂的失活原因,详细介绍了载体中引入纳米材料、稀土元素、其他金属元素(Al,Ga等)、交联剂、分子筛等对催化剂活性和稳定性的影响;综述了用S2O2-8,稀土离子,其他离子(Ag ,Ni2 ,Al3 ,Sn4 等),硫酸盐,WO3,MoO3,NO-3等代替SO2-4作促进剂,以及引入贵金属Pt和Pd改性方面的研究进展;最后展望了固体超强酸催化剂的发展前景.     

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。