超声辅助提取葫芦巴中多糖的工艺研究

采用超声辅助水提醇沉法提取葫芦巴中多糖,考察提取时间、乙醇体积、乙醇浓度、料液比对多糖提取率的影响。结果表明,最佳提取工艺参数为:料液比1∶40 g/m L,乙醇浓度90%,乙醇体积倍数40,超声提取时间1.5 h。在最佳提取条件下,葫芦巴多糖提取率1.34 mg/g,多糖纯度达67%。     

超声辅助提取葫芦巴中多糖的工艺研究

采用超声辅助水提醇沉法提取葫芦巴中多糖,考察提取时间、乙醇体积、乙醇浓度、料液比对多糖提取率的影响。结果表明,最佳提取工艺参数为:料液比1∶40 g/m L,乙醇浓度90%,乙醇体积倍数40,超声提取时间1.5 h。在最佳提取条件下,葫芦巴多糖提取率1.34 mg/g,多糖纯度达67%。     

石楠藤多糖的提取及其抗氧化活性研究

目的:通过正交试验优化石楠藤多糖提取工艺,考察石楠藤多糖清除DPPH自由基的能力.方法:考察提取温度、提取时间、料液比和醇沉体积分数对多糖提取率的影响,寻找最优提取方案;采用DPPH法研究石楠藤多糖的抗氧化能力.结果:石楠藤多糖最佳提取工艺为提取温度80℃、提取时间70 min、料液比1:50(g:mL)、醇沉体积分数...     

茶陵白芷中多糖的提取工艺优化

主要以茶陵白芷为原料,通过水提醇沉法提取茶陵白芷多糖,通过单因素试验研究提取时间、料液比、提取温度、乙醇终浓度等因素对茶陵白芷多糖提取率的影响,并对其最佳工艺进行正交试验优化.结果表明,水提醇沉法提取茶陵白芷多糖的最佳工艺条件为:料液比1:30(g/mL)、乙醇浓度90％、提取温度75℃、提取时间3 h,在此工艺条件下...     

微波辅助提取瓦松多糖的工艺研究

以提取率为评价指标,采用微波辅助法提取瓦松多糖。对微波时间、微波功率、料液比、瓦松目数、醇沉浓度分别进行单因素及正交实验。最佳工艺条件为微波时间8 min、微波功率300 W、料液比1∶40、瓦松目数60目、醇沉浓度80%,在此工艺条件下瓦松多糖提取率为4.96%。     

八角叶多糖的最佳提取工艺研究

采用水提醇沉法提取八角叶多糖,苯酚-硫酸法测定了八角叶的多糖含量。利用正交设计方法优化得到最佳提取工艺条件为:提取温度75℃、料液比1∶50、提取时间3h、提取次数2次,所得八角叶粗多糖产率达12.87%,粗多糖中多糖总含量为28.22%。     

桔梗多糖的提取工艺及抗氧化性研究

采用水提醇沉法提取桔梗多糖,以提取温度、提取时间、料液比为考察因素,通过正交实验优化提取条件。并利用邻苯三酚法和Fenton法研究桔梗多糖的体外抗氧化性。经过正交实验得出的桔梗多糖的最佳提取条件为提取温度80℃,时间3h,料液比1∶30。桔梗多糖对超氧阴离子和羟基自由基表现出较好的清除率,超氧阴离子清除率50%时桔梗多糖的浓度为0.219 mg/mL,羟基自由基清除率50%时桔梗多糖的浓度为0.08 mg/mL。     

瓜拉纳多糖制备的响应面工艺优化及抗氧化活性研究

利用响应面法优化瓜拉纳多糖的提取工艺。采用超声辅助水提法,在单因素试验的基础上,以提取时间、超声功率、液料比、提取温度为变量,以瓜拉纳多糖得率为响应值,应用Box-Benhken设计及响应面分析法进行回归分析,得到最佳提取工艺为提取时间33.5 min,超声功率155 W,水料体积质量比35 m L︰1 g,提取温度62℃,醇沉透析后冷冻干燥得到瓜拉纳多糖,此条件下瓜拉纳多糖得率为20.80%。对瓜拉纳多糖体外抗氧化活性进行评价,并以维生素C(Vc)作对照,结果发现,瓜拉纳多糖还原能力和总的抗氧化活性均与多糖浓度成正比,但都小于Vc,其中抗氧化能力接近Vc。     

响应面法优化超声辅助提取杜仲多糖的工艺研究

采用超声波辅助水提醇沉法提取杜仲粗多糖。以多糖得率为评价指标,考察料液比、提取温度、提取时间和提取功率四个因素水平,采用Box-Behnken法优化提取工艺。结果显示,超声波辅助提取杜仲多糖的最佳工艺条件为料液比1∶31,提取时间为17 min,提取温度为72℃,提取功率为89 W,理论多糖得率为6.19%,在此条件下得到的实际多糖得率为6.28%,相对误差为1.50%。优化的杜仲多糖提取工艺多糖得率高。     

超声波辅助提取银杏落叶中多糖的工艺初探

以银杏落叶为原料,采用超声波辅助水提醇沉的方法提取银杏落叶中的多糖,通过单因素试验和响应曲面法对银杏落叶中多糖提取的工艺进行初探。结果表明：最佳提取工艺条件为5.0 g银杏落叶粗粉,超声波功率600 W,液料比40∶1（mL∶g）,提取温度84 ℃,提取时间50 min,多糖提取得率6.61 %。由于本研究只是对银杏落叶中多糖提取工艺的初步研究,因此选择提取的液料比时未深入考虑"少量多次,总液比尽量少"的提取原则。     

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.     

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.     

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。     

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.     

Inorganic/organic nanocomposite coatings: The next step in coating performance

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Some Large Wood-Boring Beetles in Southeastern USA

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.