氮气增强溶液雾化技术制备聚乙二醇微粒

以超临界流体增强溶液分散技术为基础,用N2取代C02以实现该过程更好的雾化效果.实验研究以聚乙二醇(PEG6000)/丙酮溶液制备PEG微颗粒,探讨预膨胀压力和溶液流量对粒径及粒径分布的影响.结果表明,超临界N2增强的溶液雾化技术可以制得形态基本上为球形的PEG微粒,并且粒径分布可以方便地控制在1～5μm.PEG微粒随预膨胀压力增大而减少,粒径分布变窄;低PEG/丙酮溶液流量下制备的微粒粒径分布较窄.     

基于超临界流体技术的四环素超细微粒制备

吸入式给药既要求药物微粒有合适的平均粒径,又要求粒径分布在较小的范围内。利用近两年提出的超临界流体膨胀减压过程,以四环素-水+乙醇-二氧化碳系统为研究对象,成功制备了适于吸入式给药的四环素超细微粒,系统分析了混合器压力和温度、溶液浓度及进液速率对微粒形态,粒径和粒径分布的影响。结果表明:利用超临界膨胀减压过程,以水和乙醇的混合溶液为溶剂,可制备出粒径在1～3μm的四环素超细微粒,且大部分微粒形态呈完好的球形;各影响因素对微粒粒径及其分布均有不同程度的影响,其中混合器压力和溶液浓度对微粒粒径及其分布的影响最明显,进液速率和混合器温度的影响较小。在研究操作范围内,较为理想的操作条件为混合器压力12MPa、温度60℃,溶液浓度15mg·mL-1,进液速度5mL·min-1。     

超临界快速膨胀技术制备超细聚苯乙烯

以丙烷为超临界溶剂，运用超临界溶液快速膨胀技术成功制得了微米级聚苯乙烯微粒，并考察了超临界溶液快速膨胀过程中溶液浓度、预膨胀温度、喷嘴结构和接收距离等对微粒粒径的影响。结果表明：制得的微粒形态良好、粒径分布较窄；当其它操作条件保持不变时，增加溶液浓度、降低预膨胀温度、增大喷嘴直径、减小喷嘴长度以及降低样品收集距离，都能有效地降低粒径。     

超临界CO2法制备超细HMX颗粒

考察了预膨胀压力、HMX丙酮溶液初始浓度、取样停留时间及其他因素对制备HMX超细微粒粒度和晶体性质的影响.制备的超细HMX微粒平均粒径在350 nm以下,一部分微粒粒度小于100 nm.结果表明,预膨胀压力对HMX颗粒尺寸的影响较大,压力增加,HMX平均粒度变小,粒度分布变窄;HMX丙酮溶液初始浓度对HMX的粒度和粒度分布有很大影响,初始浓度越小平均粒径就变小,粒度分布变窄.停留时间及喷嘴尺寸对颗粒粒度、粒度分布及其形貌都有不同程度的影响.     

不同溶剂条件下利用SEDS法制备乙基纤维素微粒的实验研究

分别利用二氯甲烷、丙酮和乙醇作为溶剂采用超临界流体增强溶液分散法(SEDS)制备了乙基纤维素微粒,考察了不同压力、温度和溶剂条件下所制备微粒的粒径大小及形态。实验表明:在体系亚临界和超临界状态下制备的微粒粒径及形态完全不同;聚合物的玻璃化温度的降低对微粒的形态影响比较大;溶剂对微粒粒径及形态也有较大影响,特别是对可制备微粒的压力及温度的范围的影响。     

超临界辅助雾化法制备红霉素超细微粒

超临界辅助雾化(SAA)过程是近两年才提出的一种制备纳、微米粉体微粒的新方法,是一种高效的超细粉体制备技术,在药物超细化处理方面有广阔的应用前景.在自建的超临界辅助雾化过程实验装置上,以红霉素-乙醇-二氧化碳系统为研究对象,分别研究了混合器压力和温度、溶液浓度及进液速率对微粒形态和粒径的影响.实验结果表明:选用乙醇做溶剂可制备出粒径在1～3 μm的红霉素超细微粒,大部分微粒形态呈完整的球形;各影响因素对微粒粒径及粒径分布均有不同程度的影响,其中混合器压力对微粒粒径及粒径分布的影响最明显,混合器温度的影响最小,微粒粒径及粒径分布可通过改变操作参数进行控制;在本研究范围内,最优操作条件为混合器压力10.5 MPa,混合器温度70℃,溶液浓度15 mg·min-1,进液速度9 mL·min-1.实验制得的微粒适用于吸入式给药.     

超临界流体技术制备三棕榈酸甘油酯微粒

利用气体饱和溶液微粒形成技术实验装置,分别用超临界N2和超临界Co2制备三棕榈酸甘油酯微粒,探讨压力、温度以及喷嘴大小等工艺参数对微粒（粒径、粒径分布和形貌）的影响。结果表明：N2辅助过程得到的微粒基本为球状;预膨胀压力越高,粒径越小,粒径分布越窄;100μm喷嘴下制得的微粒粒径最小,且分布较均匀。CO2辅助过程得到的微粒部分为球状,部分为针状和片状;预膨胀压力越高,粒径越小,粒径分布越窄;喷嘴直径大小对微粒平均粒径及粒径分布影响不大;预膨胀温度升高,颗粒的粒径稍微增大。CO2辅助过程得到的微粒粒径比N2辅助过程得到的微粒粒径稍大,但两者的粒径分布相差不大。     

超临界反溶剂过程制备银杏叶提取物超细微粒

超临界反溶剂过程是近年来提出的一种制备纳微米粉体材料的新方法。应用超临界反溶剂过程实验装置制备银杏提取物(GBE)超细微粒,实验中以乙醇为溶剂,超临界CO2为反溶剂,制备出平均直径在1μm至2μm范围内的GBE超细微粒。同时研究了操作压力、操作温度及二氧化碳与溶液流率比等操作参数对制备的超细微粒粒径、形态及粒径分布的影响。实验结果表明：操作压力、温度对制备的GBE微粒影响较为显著。     

超临界反溶剂过程制备灰黄霉素超细微粒

超临界反溶剂过程(SAS)是近年来提出的一种制备纳微米粉体的新方法。通过一套超临界反溶剂过程间歇式实验装置,以灰黄霉素、丙酮和二氧化碳系统为研究对象,实验研究了SAS过程参数对制备的微粒形态及其尺寸的影响。当操作条件为10 MPa,40℃,溶液浓度13.3 mg/mL和溶液流速1.5 mL/min时,制备了较为理想的灰黄霉素微粒,粒径分布均匀、形状基本呈球状;当8 MPa,42℃,溶液浓度15 mg/mL和溶液流速4.0 mL/min时,微粒粒径分布比较均一、主要呈细小针状。研究结果表明:采用丙酮作为有机溶剂,可制备出不同大小和形态的灰黄霉素超细微粒。这为改变灰黄霉素传统制剂做了前期准备工作,为制成可持缓释药物提供了可能性。     

水力空化混合强化超临界流体辅助雾化制备罗红霉素超细微粒

分析了超临界流体辅助雾化（SAA）过程,发现饱和器内超临界二氧化碳与溶液的混合是SAA成功的关键因素之一,由此引入了水力空化混合器以强化饱和器内两相间的传质。在自行组建的引入水力空化混合器的超临界流体辅助雾化（SAA-HCM）装置上,以罗红霉素为模型药物,考察了混合器压力、沉淀器温度、溶剂、进料中CO₂与液体溶液流量比（R）和溶液浓度对微粒形态和粒径的影响。结果表明,水力空化混合器能有效地强化两相间的传质,SAA-HCM工艺可制备出罗红霉素超细微粒,大部分微粒形态呈球形,通过改变操作参数可制得粒径在1～3 μm的适于吸入式给药的气溶胶药物微粒和粒径小于1 μm的超细微粒。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.     

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.     

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.