芦荟在护肤化妆品中的保湿性的研究

本文对护肤化妆品中芦荟的保湿性进行了探讨。实验表明，芦荟具有较好的保湿效果。在护肤霜中，芦荟原汁的最佳保湿浓度为45％--55％，其保湿性优于5％的甘油和2％的1．3丁二醇；在护肤液中，芦荟原汁的最佳保湿浓度为35％--50％，其保湿效果优于5％甘油和0．1％透明质酸。     

γ-聚谷氨酸的保湿性研究

采用体外称重法考察了γ-聚谷氨酸溶液的浓度、p H对其保湿性的影响,并比较了γ-聚谷氨酸与透明质酸、甘油水溶液的保湿性差异。研究结果表明,γ-聚谷氨酸溶液的浓度越高,保湿效果越好,但二者不成正比例关系。γ-聚谷氨酸溶液在中性和偏碱性环境下的保湿性明显优于酸性和偏酸性环境。0. 5%γ-聚谷氨酸、透明质酸和甘油水溶液都具有良好的保湿性,其保湿性排序为:透明质酸γ-聚谷氨酸甘油。     

芦荟保湿防晒霜的研制

介绍了体系的pH值和芦荟的含量对芦荟的保湿性、防晒性的影响，实验结果表明，当体系的pH值为5.5，芦荟的含量为40％时能同时获得较好的保湿性和防晒性。     

玉竹多糖的保湿和吸湿性能研究

以化妆品常用保湿剂甘油、聚乙二醇和透明质酸钠作为对照试样,分别在高湿度环境和低湿度环境比较玉竹多糖和对照试样的吸湿、保湿性能。研究结果表明,玉竹多糖和透明质酸钠的吸湿性能优于甘油和聚乙二醇10000,在低湿度的环境下,玉竹多糖的吸湿能力优于透明质酸钠。同时,玉竹多糖的保湿性能优于甘油和聚乙二醇10000,和透明质酸钠的保湿性能相当。玉竹多糖是一种值得开发的新型保湿剂,将其自制成面膜,检测面膜的保湿性能优异。     

低聚壳聚糖的保湿特性及其在化妆品中的应用

以透明质酸(HA)及甘油为参照,利用皮肤测试仪测定皮肤水合率,考察低聚壳聚糖在涂抹不同时间段后的保湿性能及其在不同浓度下的保湿效果.结果表明,甘油保湿性能受环境湿度影响较大,而低聚壳聚糖和透明质酸受其影响较小;在相同涂抹时间下,随着低聚壳聚糖的浓度逐渐增加至0.75％,其水合率逐渐增加至最大值,之后逐渐减小.0.75％的低聚壳聚糖水合率高于0.1％HA.此外,低聚壳聚糖与常规化妆品成分相容性良好,产品外观、pH值、微生物总数、热稳定性等项目均合格.     

昆布氨酸的吸湿保湿性及动力学研究

通过将自制的昆布氨酸与原料L-赖氨酸盐酸盐以及甘油和透明质酸进行对比,对昆布氨酸的吸湿性能和保湿性能进行了研究,并对其吸湿过程作了初步的动力学分析。结果表明:昆布氨酸在相对湿度43%时的最大吸湿率为43.7%,保湿率为100.7%;在相对湿度81%时的最大吸湿率为85.1%,保湿率为103.8%;其吸湿性和保湿性均优于L-赖氨酸盐酸盐、甘油和透明质酸;昆布氨酸的吸湿过程符合二级吸附动力学模型,相关系数达到0.99以上。     

几种常用保湿剂的保湿性能研究

对透明质酸钠、小分子透明质酸钠、金钗石斛茎提取物、β-葡聚糖、芦荟凝胶提取液、Aquaxyl(含木糖醇基葡糖苷、脱水木糖醇、木糖醇)、银耳提取液、海藻糖、神经酰胺9种常用的保湿成分30 min和2 h后的皮肤水分变化率以及保湿能力(相对于质量分数4%的甘油保湿效果)进行测定,每种成分选择两个水平标准。实验结果表明,在30 min和2 h后皮肤水分值变化率均在20%以上的保湿剂有小分子透明质酸钠组、2.00%金钗石斛茎提取物、神经酰胺组、3.00%β-葡聚糖;30 min和2 h后保湿能力值均大于1的保湿剂有小分子透明质酸钠、2.00%金钗石斛茎提取物、神经酰胺。综合两者,小分子透明质酸钠、金钗石斛茎提取物、神经酰胺是较为理想的保湿成分。     

鲑鱼皮胶原蛋白肽的保湿性研究

以鲑鱼皮为原料,采用酸浸-水提法得到鲑鱼皮明胶,并通过酶解制备了鲑鱼皮胶原蛋白肽,其中超过91.5%的鲑鱼皮胶原蛋白肽分子量小于1 000 Da。通过葡聚糖凝胶G-15层析柱分离出5种组分,按其分子量的大小依次为:S1S2S3S4S5。体外试验结果表明,相对湿度81%的环境下,吸湿性顺序为:S5S4甘油鲑鱼皮胶原蛋白肽S3S2S1≈透明质酸鲑鱼皮明胶;保湿性顺序为:S5≈S4S3S2甘油鲑鱼皮胶原蛋白肽S1透明质酸鲑鱼皮明胶。相对湿度43%的环境下,吸湿性顺序为:S5甘油S4鲑鱼皮胶原蛋白肽≈S3透明质酸S2S1鲑鱼皮明胶;保湿性顺序为:S5S4甘油S3≈鲑鱼皮胶原蛋白肽透明质酸≈S2S1鲑鱼皮明胶。皮肤测试结果表明,涂抹含鲑鱼皮胶原蛋白肽的护肤品能够显著提高皮肤水分含量和降低经表皮失水率(TEWL),小分子鲑鱼皮胶原蛋白肽的保湿效果优于鲑鱼皮明胶。     

透明质酸等化妆品用生物活性多糖吸湿保湿性能测定

目的：研究单一生物活性多糖及复配物的吸湿保湿性能。方法：通过干燥器控制湿度的方法对透明质酸、鲨鱼软骨素、海藻酸钠、水溶性壳聚糖、卡拉胶寡糖等天然保湿材料与常用保湿剂甘油进行吸湿和保瀑性能测试。结果：在RH81％条件下,各试样吸湿能力顺序为：卡拉胶寡糖,甘油,海藻酸钠,水溶性壳聚糖,透明质酸〉鲨鱼软骨素;在RH43％条件下,各试样吸湿能力顺序为：甘油,海藻酸钠,水溶性壳聚糖,透明质酸,卡拉胶寡糖,鲨鱼软骨素。硅胶环境下,各试样的保湿能力顺序为：透明质酸〉水溶性壳聚糖〉卡拉胶寡糖〉鲨鱼软骨素〉海藻酸钠〉甘油。遥过对5种聚糖的两两复配实验,筛选出卡拉胶寡糖、水溶性壳聚糖、透明质酸3种生物活性多糖与其它多糖复配效果较好。结论：本实验所采用的吸湿、保湿性能评价方法准确、简单、可靠,适用于各种类型的保湿剂,可作为一种化妆品用保瀑剂的性能评价方法。     

单一保湿剂体外保湿功能的评价

通过测试神经酰胺、透明质酸、海藻糖、芦荟凝胶汁、生物因子等5种单一保湿剂在不同环境湿度(85%和62%)下的保湿率和相对保湿率,并对单一保湿剂在相对湿度为62%时放置4 h后的相对保湿率差异性的显著与否进行了分析。结果表明,保湿剂在高湿度(85%)环境中的保湿性能高于低湿度(62%),不同单一保湿剂在两个相对湿度下保湿性能的变化有差别。对5种单一保湿剂的体外保湿功能评价方法的可行性进行了讨论。体外保湿功能的评价方法可对保湿剂进行初步筛选。     

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。