黑种草籽油的超临界CO_2萃取及其GC-MS分析

以新疆瘤果黑种草籽为原料,采用超临界CO2萃取技术(SFE-CO2)研究了瘤果黑种草籽油的萃取工艺,并对其化学成分进行了GC-MS分析。得到瘤果黑种草籽油较适宜的工艺条件为:萃取压力20 MPa,萃取温度35℃,萃取时间2 h,CO2流量20 kg/h。在该工艺条件下,黑种草籽油的得油率达36.33%。GC-MS检测出6种脂肪酸成分,主要为不饱和脂肪酸,其中,亚油酸质量分数60.95%,油酸质量分数20.54%,8,11-二十碳二烯酸质量分数2.43%,不饱和脂肪酸的质量分数近84%。     

超临界CO_2萃取维药芹菜根油及其成分分析

以新疆地产芹菜根为原料,采用超临界CO2萃取技术,通过单因素和L9(34)正交实验考察了超临界CO2萃取中萃取压力、萃取温度、时间以及CO2流量对芹菜根油提取率的影响,并用GC-MS技术分析鉴定了所得芹菜根油中化学成分。结果表明,各影响因素影响顺序为:压力(温度(时间;当原料的颗粒度40～60目、CO2流量25kg/h时,超临界CO2萃取芹菜根油的优化工艺条件为:萃取压力20MPa,萃取温度35℃,萃取时间60min,在该工艺条件下萃取芹菜根油的萃取率达5.23%,所得芹菜根油共分离鉴定出了11种脂肪酸,被鉴定出来的脂肪酸成分相对质量分数占总脂肪酸组分的98.84%,主要成分为不饱和脂肪酸。其中相对质量分数最高的为12-十八碳烯二酸(相对质量分数48%,下同),其次为9-十八碳烯酸(15.50%)、十二烷酸(14.2%)和十六烷酸(11.2%)。     

超临界CO2萃取山苍子核仁油的工艺研究

研究了用超临界CO2流体萃取山苍子核仁油的萃取工艺,探讨了各种影响因素对山苍子核仁油萃取率的影响,通过正交试验确定了超临界萃取的最佳工艺为：萃取温度45℃、萃取压力25 MPa、CO2流量220 L/h、萃取时间80 min。在此条件下,山苍子核仁油萃取率84.5%。研究证明了加入溶剂和剥壳均可提高山苍子核仁油的萃取率。     

超临界CO2萃取迷迭香油工艺及其GC—MS分析研究

本文研究了超临界CO2 对迷迭香油的萃取工艺 ,结合温度、压力、CO2 流量及时间等因素对迷迭香油萃取率的影响 ,采用四因素 ,三水平的正交设计 ,得出迷迭香油萃取率最佳工艺条件为压力 (MPa) 3 0 ;温度 (℃ ) 3 5;CO2 流量 (l/h) 2 0 ;萃取时间 (小时 ) 2 ;并用GC -MS分析了迷迭香油的组成 ,得到了 2 2种成分 ,桉叶油素的含量最高 ,超临界萃取得到的迷迭香油组分“天然”全面。     

均匀设计法优化超临界萃取姜油树脂工艺条件的研究

采用均匀设计法,考察了CO2超临界萃取过程中萃取压力、萃取温度、萃取时间及萃取剂CO2流量4个因素对姜油树脂萃取率的影响。结果表明,超临界萃取姜油树脂的最佳工艺条件为:萃取压力30 MPa,萃取温度50℃,萃取时间4.5 h,CO2流量为26 kg/h,在此条件下,姜油树脂萃取率为5.27%。     

超临界CO2萃取柚子花挥发成分的工艺研究

以新鲜柚子花为原料,研究了超临界CO2萃取柚子花挥发成分的工艺,系统地探讨了萃取温度、萃取压力、萃取时间、CO2流量对得率的影响.结果表明:超临界CO2萃取柚子花挥发成分的工艺切实可行,较适宜的工艺条件为:压力16～18MPa,温度大于47℃,时间100～120分钟,CO2流量24～27L/min.     

超临界CO_2萃取山苍子核仁油的工艺研究

研究了用超临界CO2流体萃取山苍子核仁油的萃取工艺,探讨了各种影响因素对山苍子核仁油萃取率的影响,通过正交试验确定了超临界萃取的最佳工艺为:萃取温度45℃、萃取压力25 MPa、CO2流量220L/h、萃取时间80min.在此条件下,山苍子核仁油萃取率84.5%.研究证明了加入溶剂和剥壳均可提高山苍子核仁油的萃取率.     

超临界萃取沙棘油的研究

以沙棘果渣和沙棘籽为原料,分别进行沙棘果油和沙棘籽油的CO2超临界萃取的工艺研究,实验表明沙棘果油的最佳萃取条件为：温度40℃,压力30MPa,时间2h,CO2流量25kg／h;沙棘籽油适宜萃取条件为：温度45℃,压力30MPa,时间0．5h,CO2流量20kg／h。     

超临界CO2萃取丁香花蕾的工艺研究及对萃取物的GC—MS分析

本文应用超临界二氧化碳技术 ,研究了丁香花蕾的最佳萃取工艺。结合温度、压力、堆积密度、CO2 流量等因素对丁香花蕾提取物的萃出率的影响 ,采用四因素三水平的正交设计 ,得出丁香花蕾油萃取的最佳工艺条件为 :压力30MPa ,温度 4 5℃ ,CO2 流量 10L/h ,低堆积密度。作者还对萃取出的丁香花蕾油进行了GC—MS成分分析     

超临界萃取花生中主要成分的研究

采用超临界CO2萃取花生油脂中主要成分,研究了萃取压力、萃取温度、萃取时间和夹带剂用量等对萃取率的影响。结果表明,在CO2流量为10~12 L/h的前提下,最佳工艺条件是:萃取温度45℃,萃取压力30 MPa,萃取时间2.0 h,夹带剂用量20 mL。在此条件下,花生油脂的萃取率可达50.39%。影响提取率的主次因素为萃取压力萃取时间萃取温度夹带剂用量。     

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。