一株脂肽类生物表面活性剂产生菌的性能及其影响因素研究

通过对实验筛选出一株产脂肽类生物表面活性剂的菌株BW-23,进行性能及其影响因素研究.结果表明:脂肽表面活性剂的CMC浓度为70 mg/L时,表面张力为31.0 mN/m;发酵液稀释10倍后,乳化指数仍为24.72％;在10～60℃间菌株BW-23所产的生物表面活性剂的耐热性较好;菌株BW-23在pH值为5.0～8.0时表面活性最好;当NaCl浓度小于15％时,菌株BW-23水溶液的表面张力变化幅度最小;当Ca2+浓度达到5000 mg/L时,菌株BW-23水溶液的表面张力为30.5 mN/m.     

低成本原料发酵生产生物表面活性剂及其特性研究

以低成本的泔水油和豆粕为碳、氮源,发酵培养不动杆菌菌株XH-2(Acinetobacter sp.XH-2)生产生物表面活性剂。以表面张力及排油圈直径为考察指标,对菌株XH-2产生物表面活性剂的发酵条件进行单因素优化,并研究了该生物表面活性剂的稳定性。结果表明,菌株XH-2在最优培养基(泔水油3%、豆粕5%、氯化镁2%、磷酸氢二钾6%、磷酸二氢钾3.8%、三氯化铁0.5%、氯化钠2%和初始pH值6.0)中发酵培养2d后,所产的生物表面活性剂的临界胶束浓度为200mg·L~(-1),其使发酵液的表面张力由73.01mN·m~(-1)降至25.25mN·m~(-1),具有广泛的温度、pH值和盐度适应性,初步的成分分析结果表明该生物表面活性剂可能为糖脂类。     

脂肽类生物表面活性剂的研究进展

脂肽类生物表面活性剂是一类由微生物产生的次级代谢产物,具有独特的化学结构,表现出优良的表面活性和生理特性。简介了脂肽类生物表面活性剂的产生菌及其种类,重点介绍了海洋微生物所产的脂肽类表面活性剂,并展望了其研究前景。     

脂肽-糖脂混合型生物表面活性剂的性能及助剂

分离提取了枯草芽孢杆菌Bacillus subtilis THY-8发酵产物中的生物表面活性剂,采用飞行时间质谱鉴定为鼠李糖脂和表面活性素、芬芥素等的混合物。考察了该混合型生物表面活性剂的性能,研究了其对油砂原油的驱油效率,并探索了合适的助剂种类及配伍浓度。结果表明,THY-8所产的脂肽-糖脂混合型生物表面活性剂具有良好的表面活性、热稳定性和乳化性,pH值为5.5时表面张力为27.59 mN/m,临界胶束浓度为15 mg/L;在70 ℃放置5天,表面张力基本不变;可将液体石蜡乳化形成粒径10～30 μm的乳液。正辛醇助剂与该混合生物表面活性剂复配后界面张力降低到10?3 mN/m,驱油效率提高3.2倍。含0.9 g/L生物表面活性剂的发酵液驱油效果与正辛醇-生物表面活性剂复配体系相当。     

一种漆脂基季铵盐双子表面活性剂的合成与性能

以漆脂、环氧氯丙烷、二乙醇铵、1,4-二溴丁烷为原料,合成了一种漆脂基季铵盐双子表面活性剂。采用红外光谱、核磁共振碳氢谱对其结构进行分析,并对产物的表面性能进行分析。结果表明:合成产物临界胶束浓度(cmc)为5×10-4mol·L-1,表面张力(γ)可达33.6 mN·m-1;当质量分数为0.1%时,分出5 mL水的时间为10 min;表面张力和乳化性能与传统的十六烷基三甲基溴化铵(CTAB)相当。     

一种新型双联两性表面活性剂的合成与性能

采用1,4-丁二醇、马来酸酐、环氧氯丙烷、十六烷基叔胺为主要原料,合成了一种新型双联(Gemini)两性表面活性剂--丁二醇双琥珀酸一氯羟丙基季铵双酯磺酸钠(HDBC).红外光谱和质谱分析确证,合成的表面活性剂为目标产物.该表面活性剂水溶液最低表面张力为25.92 mN.m-1、临界胶束浓度为0.01 g.L-1;并考察了其发泡、稳泡性、乳化力和钙皂分散力.     

青海花土沟油田产生物表面活性剂本源菌的实验研究

采用排油圈、血平板等几种方法从青海花土沟油田分离出4株产生物表面活性剂菌,通过L16(45)正交实验,找出最佳菌种和最佳培养基,最佳产表面活性剂菌为BIOS682.BIOS682经16SrDNA基因序列分析鉴定为土壤短芽孢杆菌(Brevibacillus agri).BIOS682菌的最优培养条件为:花土沟原油40 mL·L-1、蛋白胨6 g·L-1、pH 7.2、培养温度为45℃.在此条件下培养3 d,培养液的表面张力从71.8251 mN·m-1降为29.8932 mN·m-1.     

含松香骨架甜菜碱类两性表面活性剂的合成

以脱氢枞酸为原料,合成了3种新型含松香骨架的甜菜碱类表面活性剂:N-(2-脱氢枞酰氧基)乙基-N,N-二甲基羧甲基甜菜碱,N-(2-脱氢枞酰氧基)乙基-N,N-二甲基磺丙基甜菜碱和N-(2-脱氢枞酰氧基)乙基-N,N-二甲基磷酸酯甜菜碱。通过红外和核磁共振氢谱对产物结构进行表征,3种甜菜碱cmc分别为3.16 mmol.L-1、3.01 mmol.L-1和2.56 mmol.L-1,此时表面张力分别为31.91 mN.m-1、33.20 mN.m-1和25.79 mN.m-1,说明3种甜菜碱具有好的表面活性。     

一种全氟辛基两性磷酸酯氟碳表面活性剂的复配研究

对一种全氟辛基两性磷酸酯氟碳表面活性剂协同作用进行了研究,考察了该表面活性剂与无机盐、阴离子碳氢表面活性剂、阴离子氟碳表面活性剂和非离子氟碳表面活性剂的复配性能,并对结果进行了讨论。研究表明:该两性磷酸酯氟碳表面活性剂自身表面张力为24.0 mN/m;电解质氯化钠对该两性磷酸酯氟碳表面活性剂影响显著,可使表面张力下降到22.4 mN/m;阴离子碳氢表面活性剂十二烷基硫酸钠(SDS)可使表面张力降至21.4 mN/m;阴离子氟碳表面活性剂全氟丁基磺酸钾和四乙基全氟辛基磺酸铵分别使表面张力降至20.9 mN/m和20.2 mN/m;而非离子氟碳表面活性剂N-乙基-N-聚氧乙烯(9)醚-全氟辛基磺酰胺能使表面张力降至20.9 mN/m。     

一种三硅氧烷硫酸盐表面活性剂的合成及性能

以1,1,1,3,5,5,5 -七甲基三硅氧烷(TSO)、甲基丙烯酸羟丙酯和氨基磺酸为原料合成了一种三硅氧烷硫酸盐表面活性剂;通过IR和1HNMR对合成的中间体及最终产物的结构进行了表征,并对其表面活性、泡沫性能和渗透性能等进行了测试.结果表明,三硅氧烷硫酸盐表面活性剂的最低表面张力(γcmc)为23.3 mN· m-1,临界胶束浓度(cmc)为3.16×10-2 tmol·L-1;该表面活性剂有较好的渗透性能,但是起泡性和稳泡性不强.     

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.     

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.