甲基肼苦味酸盐的合成与性能

将苦味酸与液体推进剂甲基肼进行反应,合成了甲基肼苦味酸盐,通过元素分析、红外光谱分析、核磁共振对其结构进行了表征,利用TG-DTG和DSC对其热分解性能进行了分析;利用Kissinger法研究了甲基肼苦味酸盐的热分解并计算了其热分解活化能,通过非等温DSC曲线的特征数据计算了其热爆炸临界温度。结果表明,甲基肼苦味酸盐热分解主要发生在170.8～225.3℃之间,其分解过程为放热反应,熔点约为120℃,其非等温动力学方程式为ln(β/T~2_p)=-15.393(1/T_p)+23.288,热分解活化能E为127.98kJ/mol,指前因子ln(A/s~(-1))为26.04,热爆炸临界温度T_b为171.33℃;甲基肼苦味酸盐具有合成工艺简单、反应快速及热稳定性良好等特点,可用于甲基肼的报废处理及再利用。     

耐高温聚酰胺6T/66的热降解机理

采用热重分析法测试了聚酰胺6T/66 (PA6T/66)的热稳定性,确定了热降解机理函数,通过裂解气相色谱-质谱(Py-GC-MS)法分析了PA6T/66的热裂解产物,并通过热裂解产物分析了其热降解过程。结果表明,PA6T/66在不同升温速率下的降解过程均为一步降解。通过三种“model-free”的拟合方法(KAS,FWO和Tang)确定了PA6T/66的热降解活化能平均值为224.90 kJ/mol,并通过Coats-Redfern积分法确定了其热降解机理函数类型为三级减速型反应(F3型)。进一步通过Py-GC-MS分析了PA6T/66树脂的热裂解产物为二氧化碳、环戊酮、正己胺、苯甲腈等物质,并通过热裂解产物推测了其热降解过程的反应方程式。     

N-脱氢枞基丙烯酰胺的合成、表征及其聚合性能分析

以歧化松香为原料,先制得脱氢枞胺,再与丙烯酰氯经酰胺化反应合成了N-脱氢枞基丙烯酰胺单体,经提纯为液相色谱纯度97.95%的白色固体。通过 FT-IR、MS、¹H NMR、¹³C NMR、TG、GPC及DSC表征了其结构和性能。结构表征结果显示成功合成了N-脱氢枞基丙烯酰胺。DSC分析显示,单一单体在151~196℃时发生热聚合,且自由基引发剂偶氮二异丁腈(AIBN)的存在可以降低其聚合温度,聚合物的玻璃化转变温度在100.34℃。TG分析显示,聚合物在209~483℃发生热分解。对N-脱氢枞基丙烯酰胺聚合物进行GPC分析,结果为M_n=4 301,M_w/M_n=1.56。     

棉籽酸化油的理化性质及脂肪酸组成分析

采用气相色谱法分析了棉籽酸化油的脂肪酸组成,并对其理化性质进行了研究。分析结果表明,棉籽酸化油的含油率为91.33%,酸值为144.35mgKOH/g,碘值为116.58gI2/100g,皂化值为199.80mgKOH/g;其主要脂肪酸为棕榈酸(21.29%)、硬脂酸(2.29%)、油酸(23.72%)、亚油酸(50.23%)和亚麻酸(0.39%),其中不饱和脂肪酸的含量高达74%,具有很高的工业利用价值。     

一种膨润土的表征及其对重金属离子吸附研究

以原矿膨润土为原料，对其结构进行表征和分析。然后从单因素条件分析膨润土对Cu²⁺、Cd²⁺、Pb²⁺的吸附效果。结果表明：在相同条件下，膨润土加入量为0.30 g、温度为25℃时，Cu²⁺初始浓度为200 mg/L,溶液pH值为5.0,其最大吸附率为99.92%;Cd²⁺初始浓度为150 mg/L,溶液pH值为6.0,其最大吸附率为99.84%;Pb²⁺初始浓度为50 mg/L,溶液pH值为3.5,其最大吸附率为99.12%。竞争吸附中膨润土对Cd²⁺吸附效果最佳。此研究对处理含重金属离子的废水具有较好的潜在价值。     

毛竹纳米纤丝化纤维素/TiO2气凝胶的制备及表征

以钛酸四丁酯为原料,纳米纤丝化纤维素(NFC)为模板,制备NFC/TiO₂气凝胶。采用扫描电子显微镜(SEM)、X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、比表面积及孔径分析仪对其进行表征。结果表明:NFC/TiO₂气凝胶中NFC保留了其原有的空间网络结构;TiO₂主要以颗粒的形式附着在NFC表面;通过BET分析可知其比表面积为12.55 m²/g,平均孔径为17.07 nm。     

硅橡胶/氟橡胶共混胶的硫化及热稳定性

采用机械共混法制备了质量比为10/90的硅橡胶/氟橡胶共混胶,研究了共硫化体系和硫化条件对其力学性能的影响,并通过傅里叶变换红外光谱分析了其化学组成,通过动态力学分析研究了其结构相容性,用热重法探讨了其热稳定性。结果表明,最佳的共硫化体系为过氧化二异丙苯/三烯丙基异三聚氰酸酯体系,一段硫化宜为温度170℃、压力10 MPa、时间30 min,二段硫化宜为温度200℃、时间6 h。在共混胶中硅橡胶与氟橡胶存在部分的相容性;少量硅橡胶的加入可以拓宽氟橡胶的使用温度,使其耐热性能有所提高,耐低温性能有所改善。     

Si3N4/TiN复相陶瓷的抗氧化性能

以铁尾矿和含钛高炉渣为主要原料合成了Si3N4/TiN复相陶瓷,在热力学分析的基础上,研究了Si3N4/TiN复相陶瓷的抗空气氧化性能,并对其氧化过程进行了动力学分析.采用X射线衍射、扫描电镜和能谱等对Si3N4/TiN复相陶瓷的氧化过程、氧化后样品显微形貌进行了表征,并通过分析样品的恒温氧化质量增加曲线研究了其抗氧化...     

油菜秸秆高温水解液中单糖组分的高效液相色谱测定

建立了高温水中CO₂催化油菜秸秆水解体系中单糖的高效液相色谱（HPLC）分析的方法。其分析采用Prevail^TM ES糖柱,蒸发光散射检测器（ELSD）,流动相为乙腈/水（体积比80∶20）,等度洗脱,流速0.8 mL/min,柱温35 ℃,漂移管温度95 ℃,干燥空气作为载气,流速为3.0 L/min。20 min内阿拉伯糖、木糖、果糖、甘露糖、半乳糖和葡萄糖6种单糖得到了较好的分离,各物质线性回归方程的相关系数R²为0.999 1~0.999 7,其平均回收率为95.3 %~108.0 %,相对标准偏差（RSD）均小于3 %。     

基于C-Br键断裂还原反应合成含能化合物1,3,5-三硝基六氢嘧啶

以2-溴-2-硝基-1,3-丙二醇、叔丁胺及37%甲醛溶液为原料,通过缩合环化、硝化和NaBH4(或KI)作用下的C-Br选择性还原切断反应获得了含能化合物1,3,5-三硝基六氢嘧啶(TNHP),总收率33%(或21.11%)。通过红外、核磁、元素分析及质谱技术对TNHP及其合成中间体的结构进行了表征;通过X射线单晶衍射分析制备并测定了TNHP的单晶结构,同时以实验和理论方法进一步研究了其物理化学和爆轰性能。结果表明,TNHP在单斜晶系中以P₂₍₁/c)的空间群结晶排列,晶体密度为1.787g/cm³。其热分解温度为150.6℃,计算生成焓、爆速和撞击感度分别为-50.49kJ/mol、8388m/s和22.5J,显示了其在炸药领域的潜在应用前景。     

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.     

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。     

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.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

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.     

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.