鸡蛋白四苯基锰卟啉催化乙醇氧化性能研究

使用鸡蛋蛋白(HEW)作为载体,制备鸡蛋白四苯基锰卟啉(Mn-TPP/HEW)催化剂并进行表征.考察该催化剂在不同时间、温度和压力等反应条件下的催化活性及其催化氧化乙醇生成乙醛和乙酸的能力.在最佳反应条件下,该催化剂得到的乙醇转化率和选择性(乙醛+乙酸)分别为18.3%、70.5%.并初步提出了可能的催化反应机理.     

氨水改性氧化石墨烯高效催化 Knoevenagel缩合反应

通过浸渍法制备了氨水改性氧化石墨烯,考察了其在苯甲醛和丙二腈的Knoevenagel缩合反应中的催化性能。通过X射线粉末衍射(XRD)、拉曼光谱(Raman)、傅里叶变换红外光谱(FTIR)、NH3程序升温脱附(NH3-TPD)、元素分析等对催化剂进行了表征,考察了工艺条件对其催化剂性能的影响。结果表明:氨水改性氧化石墨烯可以有效地将NH4+固载于氧化石墨烯表面;氧化石墨烯经氨水改性后在苯甲醛和丙二腈的Knoevenagel缩合反应中表现出良好的催化性能,随着改性实验中氨水质量分数的增加,催化剂的活性不断增加。以质量分数5%的氨水为改性剂制备的催化剂(AW-GO-5%)在60℃、4 h下催化苯甲醛和丙二腈的Knoevenagel缩合反应,苯甲醛的转化率高达93.6%,产物苄亚基丙二腈的选择性为94.8%,该催化剂重复使用4次后催化活性仍较高。     

乙醇催化脱氢合成乙醛的工艺研究

采用共沉淀法制备系列CuZnAl催化剂,在固定床反应器考查了催化剂对乙醇脱氢制备乙醛并副产氢气的催化性能。研究了CuZnAl组分比例对催化剂活性的影响,并对工艺条件进行优化。结果表明:Cu∶Zn∶Al=4∶4∶2时,乙醇脱氢反应催化活性达到最高;在温度为280℃,压力为1MPa,床层空速为0.8h-1,n(乙醇)∶n(水)=2,乙醇转化率达53.6%,乙醛选择性达92.2%,副产氢气纯度高达97.5%。200h连续实验,CuZnAl催化剂催化乙醇脱氢反应转化率稳定在50%以上。     

CuBr2-吡啶离子液体催化甲醇液相一步氧化生成甲缩醛

考察了以CuBr_2与具有不同烷基支链和阴离子类型的吡啶离子液体组成的催化剂体系对甲醇一步液相氧化合成甲缩醛(DMM)的催化性能,发现CuBr_2-N-乙基吡啶溴盐催化性能最好。考察了不同催化剂组成、催化剂浓度、反应温度、氧气压力、反应时间对甲醇一步液相氧化合成甲缩醛反应的影响,得到的最佳反应条件为:n(CuBr_2)/n(N-乙基吡啶溴盐)=1.0、催化剂质量浓度为40 g/L、反应温度130℃、氧气压力3 MPa和反应时间4 h,在该条件下甲醇转化率达到26.1%,DMM选择性达到95.0%。CuBr_2-N-乙基吡啶溴盐重复使用9次后,甲醇转化率为22.2%,DMM选择性为91.2%,催化活性仍然保持稳定。     

SO_4~(2-)/TiO_2/高岭土催化合成丙二酸二乙酯

利用共沉淀-浸渍法制得固体超强酸SO_4~(2-)/TiO_2/高岭土。以丙二酸和无水乙醇为原料,SO_4~(2-)/TiO_2/高岭土为催化剂,催化合成丙二酸二乙酯。考察了合成时间、不同带水剂、带水剂使用量、n(乙醇)∶n(丙二酸)、催化剂使用量、催化剂的重复使用性能等反应条件对酯化反应效率的影响。结果表明,在n(丙二酸)=0.10 mol、n(乙醇)∶n(丙二酸)=3.0、w(催化剂)=7%、带水剂V(环己烷)=5 mL、t=3 h的条件下,酯化率可达89.60%,催化剂重复使用6次,仍具有较高的活性,表明固体超强酸SO_4~(2-)/TiO_2/高岭土催化剂具有良好的催化活性和重复使用性,可以广泛应用于催化反应中。     

炭基固体酸对芳香酸酯化反应的催化性能研究

通过重氮盐还原反应对活性炭进行磺化处理,制备炭基固体酸催化剂(简称炭催化剂),考察了炭催化剂对苯甲酸、苯乙酸、3-苯丙酸等芳香酸与乙醇的酯化反应的催化活性。结果表明,炭催化剂对苯甲酸的催化活性较低,反应10 h的催化效果仅为硫酸催化剂的6%;炭催化剂对苯乙酸、3-苯丙酸催化活性较高,10 h催化效果达到硫酸的89%。     

硫酸氢钾催化合成肉桂酸异丙酯

用硫酸氢钾催化肉桂酸与异丙醇的酯化反应,合成了肉桂酸异丙酯.研究结果表明,硫酸氢钾具有较高的催化活性.考察了肉桂酸/异丙醇摩尔比、催化剂用量、反应时间对酯产率的影响,以及催化剂的重复使用性能.在典型反应条件(肉桂酸/异丙醇/硫酸氢钾的摩尔比=1∶5.5∶0.48,回流3 h)下,所得肉桂酸异丙酯的产率为72.0%.该催化剂易于回收且可重复使用.     

硫酸氢钾催化合成肉桂酸异丁酯

应用硫酸氢钾催化肉桂酸与异丁醇的酯化反应,合成了肉桂酸异丁酯.研究结果表明,硫酸氢钾具有较高的催化活性.考察了肉桂酸/异丁醇摩尔比、催化剂用量、反应时间对酯产率的影响,以及催化剂的重复使用性能.在典型反应条件(肉桂酸/异丁醇/硫酸氢钾的摩尔比=1∶10∶0.37,回流3 h)下,所得肉桂酸异丁酯的产率为87.0%.该催化剂易于回收且可重复使用.     

硫酸氢钾催化合成肉桂酸乙酯

应用硫酸氢钾催化内桂酸与乙醇的酯化反应，合成了内桂酸乙酯。研究结果表明，硫酸氢钾具有较高的催化活性。考察了内桂酸／乙醇摩尔比、催化剂用量、反应时间对酯产率的影响，以及催化剂的重复使用性能。在典型反，条件（内桂酸／乙醇／硫酸氢钾的摩尔比=1：19：0．74，回流3h）下，所得肉桂酸乙酯的产率为97．1％。该催化剂易于回收且可重复使用。     

SO_4~(2-)/TiO_2型固体酸催化剂的催化及稳定性能研究

运用水热法制备了SO2-4/TiO2型固体酸催化剂,考察其在乙酸与正丁醇酯化反应中的催化活性。利用X射线衍射、红外光谱和热重分析考察了催化剂的结构特征和催化稳定性。结果表明,SO2-4/TiO2型固体酸催化剂具有纳米级晶粒,完善的锐钛矿晶型和较高的热稳定性;当水热温度150℃,硫酸浸渍浓度1 mol/L,水热时间24 h,m(催化剂)=0.5 g的条件下,正丁醇的转化率达到82.09%,乙酸正丁酯的选择性为100%。催化剂重复使用3次时流失较严重,之后催化活性一直保持稳定。该催化剂具有良好的催化活性和重复使用性能。     

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。