磁性SO4^2—ZrO2固体超强酸催化合成丁酸丁酯的研究

利用磁性对固体超强酸组装，制备出磁性SO4^2-ZrO2固体超强酸催化剂，应用于丁酸丁酯的合成反应中。最佳反应条件为：正丁醇0.36mol,丁醇0.2mol，磁性催化剂1.0g，带水剂甲苯15mL，反应温度为回流温度，反应时间2.0h，酯化率可达96．4％。利用催化剂的磁性可将催化剂迅速分离，回收率达83．2％，并能重复使用。     

磁性SO_4~(2-)-ZrO_2固体超强酸催化合成丁酸丁酯的研究

利用磁性对固体超强酸组装 ,制备出磁性SO2 -4 -ZrO2 固体超强酸催化剂 ,应用于丁酸丁酯的合成反应中。最佳反应条件为 :正丁醇 0 36mol,丁酸 0 2mol,磁性催化剂 1 0g ,带水剂甲苯 15mL ,反应温度为回流温度 ,反应时间 2 0h ,酯化率可达 96 4%。利用催化剂的磁性可将催化剂迅速分离 ,回收率达 83 2 % ,并能重复使用     

固体超强酸SO2-4/Fe2O3催化合成丙酸丙酯

利用制备的固体超强酸SO4^2-／Fe2O3代替浓硫酸作催化剂，将正丙酸和正丙醇酯化合成丙酸丙酯，讨论了催化剂的制备及合成丙酸丙酯的条件。实验表明：固体超强酸不仅能减少对生产设备的腐蚀，而且具有很好的催化活性，当催化剂用量为1．0g(正丙酸为0．1mol)，醇酸摩尔比为2．5：1，回流反应3h时，酯收率可达97．2％。     

磁性固体超强酸催化合成乳酸丁酯

利用磁性对固体超强酸组装 ,制备出磁性 SO2 -4/Zr O2 固体超强酸催化剂 ,应用于合成乳酸正丁酯的反应中 ,最佳反应条件为 :丁醇 0 .3mol,乳酸 0 .1 mol,磁性催化剂 1 .2 g,反应时间 2 .5 h,酯化率可达 96.5 %。利用催化剂的磁性可将催化剂迅速分离 ,回收率达 82 .5 %,并能重复使用。     

磁性纳米SO4^2-／Fe3O4-ZrO2固体超强酸催化合成己二酸二正辛酯

利用磁性对纳米固体超强酸组合，制备出磁性纳米SO4^2-／Fe3O4-ZrO2固体超强酸催化剂，并用TEM、IR、Hammett指示剂检测磁性纳米固体超强酸催化剂性能。将其用于己二酸二正辛酯（DOA）的合成反应中。得到最佳反应条件为负压下，反应温度155℃，n（正辛醇）：n（己二酸）=3．2：1，反应时间2h，w（催化剂）=1．5％，己二酸的转化率达99％。利用催化剂的磁性可将纳米颗粒催化剂迅速分离，回收率达93．8％，并能重复使用。     

磁性固体超强酸催化合成丁酸异戊酯的研究

利用磁性对固体超强酸组装,制备出磁性SO42-/ZrO2固体超强酸催化剂,应用于合成丁酸异戊酯的反应中。研究了影响反应的因素。实验表明:丁酸0.15 mol;异戊醇0.21 mol;磁性催化剂1.4 g;反应时间1.5 h,酯化率可达97.5%。利用催化剂的磁性可将催化剂迅速分离,回收率达82.2%,并能重复使用。     

磁性固体超强酸ZrO_2/SO_4~(2-)催化合成丁二酸二丁酯

以丁二酸和正丁醇为原料,磁性固体超强酸ZrO2/SO2-4为催化剂合成了丁二酸二丁酯。考察了影响酯化率的各种因素,确定最佳反应条件是:丁二酸为0 05mol,正丁醇与丁二酸的摩尔比为2 4,催化剂0 5g,甲苯5ml作带水剂,反应时间2h,酯化率91%以上。结果表明,磁性固体超强酸ZrO2/SO2-4是合成丁二酸二丁酯的优良催化剂,同时利用催化剂的磁性可将催化剂迅速分离。     

磁性纳米SO42-/Fe3O4-ZrO2固体超强酸催化合成己二酸二正辛酯

利用磁性进行了纳米固体超强酸组合,制备出磁性纳米SO4^2-／Fe3O4-ZrO2固体超强酸催化剂,并将其用于己二酸二正辛酯(DOA)的合成反应中。得到最佳反应条件：在负压下,反应温度155℃,正辛醇和己二酸的摩尔比为3.2：1,反应时间2h,催化剂用量1．5％(质量),在此条件下己二酸的转化率达99．4％。实验结果表明,利用催化剂的磁性可将纳米颗粒催化剂迅速分离,回收率达93．8％,并能重复使用。     

固体铁系超强酸催化合成丙酸异戊酯的研究

采用固体铁系超强酸代替无机酸作催化剂催化合成了丙酸异戊酯。最佳反应条件为:正丙酸:异戊醇的摩尔比为1:2．5,当反应物总量为0．56mol时,固体铁系超强酸的用量为2．0g,反应时间2．5 h,酯收率可达87．6％。     

SO4^2—／TiO2／La^3＋固体超强酸催化合成水杨酸异丙酯

以水杨酸和异丙酸为原料,稀土固体超强酸SO4^2-/TiO2/La^3 为催化剂合成了水杨酸异丙酯,考察了影响反应的因素。最佳反应条件为：醇酸比（mol:mol)为3．0：1．0,催化剂的用量为1．5g（水杨酸为0．1mol),反应时间为3.5h,温度为回流温度,酯收率可达94．8％,并且催化剂可再生重复使用。     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

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.