荧光假单孢菌PS-1发酵条件的研究

对荧光假单孢菌(P.Fluorescens)PS-1菌株的工业发酵培养基成分和发酵条件进行了研究.通过单因子实验和正交实验,确定最佳培养基组成:可溶性淀粉10 g/L,豆饼粉15 g/L,葡萄糖3 g/L,KH2PO4 0.6 g/L,CaCO3 2 g/L;最佳发酵条件:温度为28 ℃,pH为7.0,装液量为20 mL/250 mL三角瓶装量;搅拌速率200 r/min.最大发酵菌数达到1.78×1010/mL.     

花生粕混合菌发酵产挥发性物质的初步探索

对花生粕进行混合菌发酵,通过感官评价发酵醪确定适宜的混合菌发酵条件,采用同时蒸馏萃取法提取挥发性物质,并通过气相色谱法进行分析。初步确定花生粕基质料液比为0.6∶1、混合菌最佳组合为A+C(配比3∶1)、最佳蒸馏萃取温度为90℃。同时蒸馏萃取法是提取挥发性物质的有效方法,提取条件和气相色谱条件有待进一步探索优化。     

放线菌10885除草活性物质的分离鉴定

雪白链霉菌SPRI-10885菌株的发酵代谢产物对多种阔叶杂草和禾本科杂草具有显著的除草活性,通过溶剂萃取、柱层析分离、HPLC等手段,从中分离得到5个主要活性物质.经过质谱、核磁共振等分析,确定10885-Ⅰ分子质量为453、分子式为C18H23N5O9、10885-Ⅱ分子质量为535、分子式为C23H29N4O10、10885-Ⅲ分子质量为551、分子式为C23H29N5O11;另外两个分子质量分别为254和270,分子式分别为C15H10O4和C15H10O5.综合各种谱图分析确定前3个化合物的结构分别与文献报道的除草素herbicidin B、F、A相同,后两个与大豆异黄酮类物质三羟基异黄酮(genistein)、黄豆甙原(daidzein)一致.     

~(13)C、~(15)N双标记氨基脲的同位素丰度测定

采用微量高温灼烧法制备样品气,运用同位素质谱测定稳定性同位素13 C、15 N双标记氨基脲(13C、15 N3-SEM)产品的13C、15 N同位素丰度。通过实验对影响测定结果准确度的相关因素进行了考察,确定了最佳质谱转化条件为:称取1mg 13C、15 N3-SEM.HCl样品,10mg微粒状氧化铜,放入玻璃样品管,于真空状态下熔封样品管。将样品管放入马弗炉,530℃反应4h。实验表明:测定结果具有良好的精密度、重复性及再现性,满足了稳定性同位素13 C、15 N双标记氨基脲产品的同位素丰度测定的要求。     

C群和W_(135)群脑膜炎球菌发酵工艺的优化

目的优化C群和W135群脑膜炎球菌的发酵工艺,提高荚膜多糖产量。方法在5L发酵罐中,通过调整溶氧(DO)、pH值、培养温度、葡萄糖补料速率等参数,了解C群和W135群脑膜炎球菌在发酵过程中的代谢规律,优化发酵工艺,并将C群脑膜炎球菌在100L发酵罐中放大发酵。结果在发酵过程中,DO在20%～40%范围内对多糖合成无明显影响;在pH6.6左右,培养温度37℃,有利于多糖合成;发酵中间补加葡萄糖可增加多糖合成,低速补糖较高速补糖更有利于多糖合成。C群脑膜炎球菌在100L罐中放大发酵,多糖产量可达5L罐水平。结论通过参数优化,确定了C群和W135群脑膜炎球菌的最佳发酵工艺。     

一株微生物絮凝剂产生菌产絮凝剂的条件及其发酵生理研究

通过正交实验研究了絮凝剂产生菌F00产絮凝剂的条件及其发酵生理.结果表明,F00产絮凝剂的最佳条件为:初始pH值为6.5,培养温度为30℃,通气量为80 r·min-1,C/N为10;培养72 h絮凝剂活性最高达到72%.F00发酵过程中,絮凝剂生物合成最多是处于菌体快速生长之后、菌丝停止生长到开始进入繁殖阶段大量产生分生孢子的时期,因此可在此时收获絮凝剂.     

微生物发酵麻黄草提取麻黄碱的优化工艺研究

采用微生物发酵麻黄草提取麻黄碱,对麻黄草发酵条件进行了研究.确定最佳发酵条件为:茵丝体接种量10%,料液比1:1.5,发酵时间20 h,发酵温度38℃.麻黄草发酵后在常压最佳提取条件(提取次数3次,每次提取时间1 h.提取温度80℃,料液比1;10)下,麻黄碱的平均提取率为0.9%,较传统高温高压提取工艺提高了25.8%.表明微生物发酵麻黄草可以提高麻黄碱提取率,减少能源消耗,降低生产成本.     

1,13-十三碳二羧酸发酵工艺的研究

以热带假丝酵母(Candidatropicalis)为菌种发酵生产1,13 十三碳二羧酸(DCl3)是现阶段最经济的方法。通过对接种量、补碱工艺、发酵级数和空气流量的优化以及采取中间补加正十三碳烷烃(C13)、延长发酵周期等措施,确定了最佳的DC13发酵工艺,15m3发酵DC13的产量达到850kg,主要原材料正十三碳烷烃的消耗下降了11 6%。     

PVC／PU合金—碳酸钙填充防水卷材的性能

本文介绍了在PVC/PU防水卷材研制过程中,引用临界颜料体积浓度(C.P.V.C)的概念,通过力学性能及流变性能的测定,确定了活化碳酸钙在PVC/PU合金中的最佳用量。     

序批式MBBR处理低C/N生活污水

通过序批式移动床生物膜反应器(MBBR)处理低COD/TN(C/N)生活污水的试验研究,探讨了载体填充率、曝气量对处理效果的影响,确定适合反应器的填充率为53%,最佳曝气量为0.07L/h.在该实验条件下,COD平均去除率为87%左右,氨氮去除率均在93%以上,TN去除率最高为65%,发生了同时硝化反硝化现象,结果表明:反应器对低C/N生活污水有较好的处理效果.     

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。