环庚三烯酚酮对植物致病菌的抑菌研究

主要采用滤纸片法来研究环庚三烯酚酮对植物致病菌的抑菌活性,并且运用菌丝生长速率测定法得出5种供试菌的抑菌率,当环庚三烯酚酮的质量浓度〉50.00×10^-6时,对植物致病菌都有较好的抑菌效果。     

环庚三烯酚酮的合成

以环戊二烯和二氯乙酰氯为原料,应用2+2加成、扩环反应生成了环庚三烯酚酮。此方法工艺路线较简捷,产率71%,纯度为99.00%以上。     

杀菌防霉涂料

具有良好的防UV褪色性的题述组合物,含有环庚三烯酚酮金属配合物。含10％4-异丙基环庚三烯酚酮锌配合物(由4-异丙基环庚三烯酚酮钠盐和氯化锌制得)的一种丙烯酸乳液具有良好的防霉性,在UV照射下具有良好的抗褪色性。     

桉树脑类除草剂环庚草醚的合成

α－蒎烯与硫酸反应，给出１，４－桉树脑。再与锂、１，３－丙二胺反应，得萜品－４－醇，再气化后，与α－甲基氯苄反应得到环庚草醚。     

丁二烯为原料合成大环类香料

丁二烯是石油催化裂解副产的碳四馏分中最重要的C4烯烃,它可自碳四馏分往萃取分离获得,也可由丁烷和丁烯脱氢制得。丁二烯最重要的用途是用于合成橡胶。另一重要用途是先直接三聚成为环十二碳三烯,再经控制性选择加氢成为环十二碳单烯,如经彻底加氢则成为环十烷,后者经催化氧化得到环十二醇,如若继之催化脱氢便成为环十二酮。制得一系列更富利用价值的中间体。     

六溴环十二烷的研制

介绍了以环十二碳三烯溴化制六溴环十二烷的反应机理和简单易行的合成工艺,着重讨论了溶剂和催化剂对产品质量、收率的影响,经应用试验,获得较满意的阻燃效果。     

环丙基砜衍生物的合成研究

在温和的碱性条件下,以TosMIC为砜源,对2-酰基-1-氯环丙烷羧酸酯的区域进行选择性加成,直接合成具有潜在生物活性的环丙基砜类化合物,产率可高达85％,非对映选择性可超过20:1.研究结果首次证明了TosMIC与缺电子环丙烯的亲核加成反应.     

含降冰片烯多脂环化合物在高聚物上的应用

综述了含降冰片烯多脂环化合物的合成及其在配位络合聚合,环烯烃开环聚合丙烯酸多脂环酯与丙烯酸多脂环烯酯合成方面的应用;并介绍了用它合成的一系列高聚物的性质和应用。     

固体酸催化环己醇脱水制备环己烯

评述了对甲苯磺酸，五水四氯化锡、二水氯化亚锡、六水三氯化铁、一水合硫酸氢钠、Ti^4＋-、阳离子交换树脂、固体超强酸、杂多酸和沸石分子筛催化环己醇脱水制备环已烯的方法，并指出固体超强酸、条多酸和沸石分子筛是环己醇脱水制备环己烯的优良催化剂。     

环十二碳三烯连续加氢制环十二烷

探索了环十二碳三烯在滴流床中连续加氢制环十二烷的反应规律,采用ST-1催化剂,在压力2×10~6Pa、温度110C、液相空时83.4min、气液比大于3:1的条件下,环十二烷的收率可达99％以上,加氢产物可直接用于后续氧化反应。催化剂经近500h连续试验,活性和选择性均没有发生变化,可望应用于工业生产。     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.     

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.