植物多酚在化妆品领域中的应用

植物多酚具有较高的自由基清除能力和抗氧化作用,可以抵抗紫外线照射引起的皮肤老化问题,也可以抵御色素异常沉着。介绍了植物多酚在化妆品中的作用机理、添加植物多酚化妆品的制备和功效检测,阐述了植物多酚在应用过程中出现的问题和改善方法,指出植物多酚具有高安全性和高提取率,将其运用到抗衰老、美白、防晒等功能化妆品中具有良好的发展前景。     

美容化妆品中的植物多酚提取实验研究

根据美容化妆品种常用的植物多酚进行实验研究,借鉴相似相溶原理,多数植物中多酚都含有较强的酚羟基官能团。实验结果表明,利用乙醇溶剂会提取更多的植物多酚,其化学机理为植物多酚与金属离子反应,促使金属离子成显色。本实验分析结果显示提取植物多酚的最佳条件为乙醇浓度控制在35%-45%的范围。     

植物多酚复配物对水包油型膏霜化妆品抗氧化性能的影响

基于水包油型膏霜化妆品的抗氧化性能测试,研究多酚复配物的配比及在各种不同的外界条件下复配物对化妆品过氧化值的影响;同时考察了复配物配比对羟基自由基清除能力的影响.将膏霜化妆品溶液分别经过紫外光照射、加热到不同温度和添加0.1 mol·L-1 MnCl2的条件下各6 h后与添加V(路边青):V(过路黄)=2:1的植物多酚复配物以及添加合成抗氧化剂2,6-二叔丁基对甲酚的同样膏霜化妆品溶液测定过氧化值进行比较.结果表明,加入植物多酚的抗氧化效果较佳,羟基自由基清除率也较大,复配物的抗氧化活性优于合成抗氧剂2,6-二叔丁基对甲酚.     

植物多酚在橡胶中的应用研究进展

随着植物多酚化学的发展,植物多酚的化学结构和性质已逐渐被深入揭示。关于其独特的生理活性、天然活性以及应用方面的综述也屡见不鲜。植物多酚独特的化学结构和物理性质,引起了橡胶工业的注意,其在橡胶中的应用近几年得到较大的发展。在此,主要对植物多酚在橡胶中的应用进展进行了概述。     

植物成分化妆品研究进展

植物成分化妆品在近年来备受关注,因其自然和绿色的特点而受到广大消费者的喜爱。本论文旨在综述植物成分化妆品的研究进展,包括植物成分的应用和其功效等方面。通过文献综述,发现越来越多的研究探索了各种植物提取物在化妆品中的应用,如花卉提取物、植物油和植物精华等。这些植物成分在化妆品中具有抗氧化、抗皱、美白和保湿等功效。此外,还总结了植物成分化妆品研究进展的挑战和未来发展方向,如提高植物成分的稳定性和有效性,并进行更深入的安全性评估。期望对今后开发植物成分化妆品提供一些参考。     

植物精油的添加对化妆品防晒性能的影响研究

以防晒系数基准物及常见化妆品为样品,采用紫外分光度法测定其加入不同种类植物精油前后的吸光度值,比对及评价化妆品防晒性能的变化,从而判断不同种类植物精油在不同质量分数时对化妆品防晒性能的影响趋势。结果表明,在所筛选的五种植物精油中,陈皮精油和佛手柑精油会显著降低化妆品的防晒性能,其最适质量分数为1%;茶树精油对化妆品的防晒性能有增益作用,其最适质量分数为10%;植物精油对基础型化妆品影响能力较大,对护肤型化妆品影响能力较小。     

天然植物保湿成分在护肤品中的应用概况

保湿是皮肤护理的关键,皮肤保湿功能下降会导致多种皮肤问题,随着人们对化妆品安全性的重视及绿色环保的要求,绿色天然化妆品成为消费者的首选,阐述了天然植物提取物在化妆品中的研究及应用情况。     

植物源防腐剂及其在化妆品中的应用

系统介绍了主要抑菌植物和抑菌成分类型的研究进展。综述了化妆品防腐剂以及植物源防腐剂在化妆品中的应用现状,对其在应用过程中存在的问题进行了分析,指出了具有防腐作用的功能性植物提取物将是今后化妆品防腐剂的主要发展方向。     

植物多酚在有机污染物降解上的应用研究进展

植物多酚表现出强烈而稳定的电子传递能力,极具运用开发价值,已引起科学界极大地关注。植物多酚被广泛应用于环境污染物的去除,尤其是有机污染物的降解过程。本文根据植物多酚的不同角色综述了近年来国内外关于植物多酚直接或间接参与有机污染物降解的最近进展,重点介绍了植物多酚对有机污染物降解的强化作用,分析了植物多酚在有机污染物降解上的作用机理,以期为促进植物多酚在环境污染物修复上的应用和推广提出参考。     

石榴皮主要活性成分及其在化妆品中的应用研究进展

近些年来,随着人们对于化妆品的安全性的重视程度不断加深,植物提取物在化妆品中的应用也越加广泛。石榴皮作为传统的中药材,其中含有的丰富的鞣质类化合物、黄酮类化合物、多糖和有机酸等多种生物活性成分,体现出了它在化妆品中具有很好的应用价值。研究发现,石榴皮提取物可以在具有抗皱、防腐、美白、防晒等多种功效的化妆品中发挥作用。文章总结论述了石榴皮中含有的主要活性成分以及功效性研究,并讨论了石榴皮在化妆品中的应用现状以及未来的展望。     

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。