RDX改性双基球形小粒药的燃烧特性

讨论了改性双基球形小粒药中RDX颗粒的分布和RDX热分解的特点,提出了RDX改性双基球形小粒药的燃烧机理。通过密闭爆发器实验测定了RDX改性双基小粒药的燃烧特性,并对实验结果进行了理论分析。结果表明,改性双基球形小粒药中RDX与双基火药基体的分解是各自独立进行的;随着压力的升高,改性双基小粒药的燃速将大于改型双基小粒药的燃速。     

改性双基球形药的制备工艺研究

介绍了改性双基球形药的悬浮法制备工艺,探讨了增能物质含量及其改性物质的粉碎程度对球形药假密度和粒径的影响,并对溶剂用量、脱水剂浓度及驱溶速度的影响进行了讨论。     

GAP改性单基球形药制备工艺研究

讨论含氮量、表面活性剂等对单基球形药形貌及密度的影响。结果表明,含氮量增加时,单基球形药密度增大,含氮量高的NC配方比含氮量低的配方制得的球形药成球率低;在GAP改性单基球形药制备中,表面活性剂浓度为0. 1 g/m L时球形药颗粒成型最好,浓度为0. 07 g/m L及0. 13 g/m L时产品拖尾现象明显,成球率较差。较高浓度表面活性剂下能制得粒径更小的球形药;脱水剂用量增加时,改性球形药的密度增大,脱水剂用量为17. 4 g时药粒表面光滑,圆度较高,脱水剂用量为8. 7 g和26. 1 g时,药粒表面存在较多凹坑。     

高固含量推进剂模压工艺

探索了一条高固含量推进剂较安全的成型工艺路线,重点介绍了一种高固含量球形药工艺.采用内溶法制得纯硝化棉黏合剂体系及硝化棉与ETPE(含能热塑性弹性体)混合黏合剂体系的高固含量(RDX(黑索今)质量分数为55％～60％)球形药,其球形药密度接近理论计算值,颗粒饱满,粒度均匀致密.采用模压成型工艺将其压制成推进剂药柱,药柱经无损检测,均匀致密,内部无气孔.同时药柱进行了各项性能实验.研究结果表明:该工艺方法简单可行,安全可靠.     

GAP改性单基球形药的表征

采用内溶法制备了由聚叠氮缩水甘油醚(GAP)改性的单基球形药,用扫描电子显微镜(SEM)、假密度测定器、激光粒度仪和傅里叶变换红外(FT-IR)对GAP改性单基球形药进行表征。结果表明,所制得的GAP改性单基球形药圆球率较高,颗粒间无粘结,流散性好;在驱溶时采取缓慢升高真空度和温度的方法可制得较好的GAP改性单基球形药,驱溶时间从10min增长至60min时,假密度从0.5467g/cm3增大至0.8315g/cm3,适宜的驱溶时间为40～50min;搅拌速度从700r/min提高至1 500r/min时,GAP改性单基球形药的中位粒径d50从134.53μm减小至59.80μm,适宜的搅拌速度为1 000～1 500r/min。     

壳聚糖／羧甲基纤维素钠多层复合载药微囊的制备及其体外释药性能初探

文章以戊二醛为交联剂制备得到以利福平（PEP）为核，壳层材料次序为CS和CMCNa交替的多层复合载药微囊，并考察了微囊的释药机制和囊材层数对体外释药的影响。结果表明，制备的多层复合微囊球形规整，表面光滑，平均粒径约为8．44±454μm。药物被很好地包埋在多层微囊囊芯中，释药方式主要以扩散作用进行，囊材层数增加，药物的缓释性能明显。     

微气孔球形药常压传火速度的测试方法

为了简便快速地测试微气孔球形药的常压传火速度,对靶线法、半圆槽法、直管法等传火速度测试方法进行了对比,研究了测试管材料的种类、外界气流、测试管长径比等条件对常压传火速度的影响规律。结果表明,在几种测试方法中直管法操作简便,偏差小,且不受外界气流的影响;随着测试管长径比的增加,直管法测得的传火速度逐步提高;采用底部开口状态测试管得到的测试结果比底部封闭的测试管得到的结果偏大近50%;采用透明的玻璃管作为测试管可以研究传火速度和药粒的点传火现象。采用透明玻璃管测试常压状态下微气孔球形药的传火速度是可行的。     

双基球形药成球工艺的研究

以水和乙酸乙酯为介质,硝化棉、吸收药为原料,经成球、洗涤、烘干等过程制得球形药。研究了球形药的成球工艺。结果表明,球形药的成球温度、预驱量及脱水剂质量分数依次为66℃~68℃、60%、3%~5%时成球率高;随着溶剂比的提高,球形药的堆积密度增加;随着搅拌速率的提高,球形药的粒径减小。     

大颗粒磷酸氢钙(药品级)生产新工艺

大颗粒磷酸氢钙 (药品级 )的制备应同时满足 3个条件 :(1)粒径分布要求 ;(2 )颗粒形状应为球形或近似球形 ;(3)满足各种药典如ＵＳＰ、ＣＰ、ＪＰ、ＢＰ等要求。1　工艺特点　　本工艺不同于传统的磷酸氢钙 (药品级 )生产工艺 ,其主要区别在于 :(1)传统工艺为液态磷酸与轻质碳酸钙或重质碳酸钙 (俗称方解石 )悬浮液反应 ,为液固反应。本工艺为液态磷酸与经消化处理的纯净石灰水 (清澈透明 ,主要成分为氢氧化钙 )反应 ,为液液反应 ,可避免传统方法碳酸钙中携带的有害杂质 ,大大地提高了药品级磷酸氢钙的纯度 ,同时保证晶体的同一性。 (2 )本…     

GAP改性单基球形药制备工艺研究

讨论含氮量、表面活性剂等对单基球形药形貌及密度的影响。结果表明,含氮量增加时,单基球形药密度增大,含氮量高的NC配方比含氮量低的配方制得的球形药成球率低;在GAP改性单基球形药制备中,表面活性剂浓度为0. 1 g/m L时球形药颗粒成型最好,浓度为0. 07 g/m L及0. 13 g/m L时产品拖尾现象明显,成球率较差。较高浓度表面活性剂下能制得粒径更小的球形药;脱水剂用量增加时,改性球形药的密度增大,脱水剂用量为17. 4 g时药粒表面光滑,圆度较高,脱水剂用量为8. 7 g和26. 1 g时,药粒表面存在较多凹坑。     

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.     

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.     

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。     

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.