氨基功能型离子液体吸收CO_2的性能

氨基功能型离子液体在常温常压下对CO_2具有较强的吸收选择性能,在分离固定CO_2方面具有较好的应用前景。合成了4种氨基功能型离子液体,对产物进行了IR和~1H NMR表征,探究了这些功能型离子液体的CO_2吸收性能及再生性能。结果表明,4种氨基功能型离子液体均具有强于常规型离子液体的CO_2吸收性能,再生性能良好,可循环使用;离子液体的CO_2溶解度受黏度影响显著,随吸收温度的升高而降低,随吸收压力的升高,吸收剂浓度的增加而增大;强化传质能提高再生效率,多次的再生对离子液体的吸收性能没有明显影响。     

离子液体中电化学还原CO_2研究评述与展望

近百年来,伴随着矿石燃料的大量消耗,CO_2的排放量剧增,引发了全球性的生态环境和社会问题。CO_2同时也是廉价且可再生的碳资源,可作为生产醇、醚、酸、酯等重要化工品的原料。在众多吸引力十足的CO_2利用路线中,作为清洁、可控的反应过程,电化学还原固定CO_2技术在温和条件下生产化学品方面具有独特的优势。离子液体以其特有的性质被广泛用于电化学还原CO_2过程,本文对目前国内外离子液体介质中电化学还原CO_2的研究现状进行了综述,介绍了离子液体介质中电化学还原CO_2的主要反应及基本原理;针对离子液体对CO_2高效活化和转化等关键科学问题进行深入探讨,提出新型功能化离子液体的应用将成为CO_2电化学还原领域的发展方向和热点。     

离子液体固定CO2及其转化利用的研究进展

综述了新型绿色溶剂离子液体在CO2固定和转化利用领域的应用研究进展.根据离子液体的结构特征和CO2的固定机理,离子液体固定CO2可以分为常规离子液体固定、功能化离子液体固定和离子液体固定转化.常规离子液体固定CO2为物理作用过程,功能化离子液体固定CO2为化学作用过程,而离子液体固定转化CO2的过程在固定CO2的同时又实现了CO2从工业废气直接到有用化学品的转变.因此,设计合成高效的功能化离子液体来实现CO2的固定转化一体化将具有重要的意义.     

离子液体催化二氧化碳合成环状碳酸酯的研究进展

离子液体作为一种新型绿色环保介质,由于其结构可设计、稳定性高以及催化活性高等优点,使其在CO_2环加成反应的催化方面应用前景广阔。本文综述了近年来离子液体催化CO_2与环氧化物的环加成反应制备环状碳酸酯的研究进展。传统离子液体包括咪唑类、吡啶类、季铵盐季盐等离子液体,而功能化离子液体包括羟基功能化、羧基功能化等离子液体。与传统离子液体相比,功能化离子液体具有更好的催化活性。无机或有机材料负载的非均相离子液体催化剂报道较多,载体包括SiO_2、氧化石墨烯、聚合物等。非均相催化剂具备易分离、可在固定反应器中连续反应等优点,更适应工业化生产。指出了CO_2与环氧化合物反应制备环状碳酸酯过程中出现的催化剂活性低、反应条件苛刻等关键问题,因此寻求高选择性合成环状碳酸酯的环境友好的新型高效催化剂具有重要的学术意义和实用价值。     

离子液体固定和转化CO_2研究

近几年,随着化工行业的发展,CO_2的排放量也随之升高,使得全球气候变暖,人们赖以生存的环境已不堪重负,所以把CO_2吸收转化为有用的化工品已成为研究的重要方向。离子液体具有化学固定和吸收CO_2,并且还可以回收,非挥发性及对设备无腐蚀性的特点。因此,用离子液体吸收转化CO_2有重大的意义。主要综述了几种不同类型的离子液体吸收和转化CO_2的机理。     

咪唑类离子液体微胶囊的CO_2吸附和扩散行为

采用高速剪切法,制备微胶囊型固载咪唑类离子液体,研究离子液体微胶囊的微观结构、CO_2吸附量、CO_2/N2选择性、稳定性以及CO_2的扩散行为。结果表明,制备的离子液体微胶囊结构完整,且微观结构的完整性和粒径是影响CO_2吸附量的主要因素。在0. 1 MPa和298 K下,气相硅胶含量24%、离子液体58. 46%、水含量8. 77%、乙二醇含量8. 77%的样品BCE24-11,其CO_2吸附量为3. 41%,达吸附平衡仅30 min,CO_2/N2选择性为17. 05,稳定性和循环使用性较好;与纯离子液体的扩散系数值(10-11m2/s)相比较,微胶囊型结构的固载离子液体具有更快的CO_2的扩散速率。     

咪唑类离子液体微胶囊的CO_2吸附和扩散行为

采用高速剪切法,制备微胶囊型固载咪唑类离子液体,研究离子液体微胶囊的微观结构、CO_2吸附量、CO_2/N2选择性、稳定性以及CO_2的扩散行为。结果表明,制备的离子液体微胶囊结构完整,且微观结构的完整性和粒径是影响CO_2吸附量的主要因素。在0. 1 MPa和298 K下,气相硅胶含量24%、离子液体58. 46%、水含量8. 77%、乙二醇含量8. 77%的样品BCE24-11,其CO_2吸附量为3. 41%,达吸附平衡仅30 min,CO_2/N2选择性为17. 05,稳定性和循环使用性较好;与纯离子液体的扩散系数值(10-11m2/s)相比较,微胶囊型结构的固载离子液体具有更快的CO_2的扩散速率。     

多活性位点季鏻盐型功能化离子液体的二氧化碳捕集行为

采用两步法合成了三种季鏻盐型功能化离子液体[a P4443][AA]([AA]=[Triz]、[2-Op]、[2-Np]),考察了温度、CO_2浓度和烟气组分(水分、氧气)对离子液体吸收CO_2性能的影响。结果表明,在30℃、常压条件下,三种离子液体都具有较高的CO_2捕集能力,[a P4443][Triz]、[a P4443][2-Op]和[a P4443][2-Np]对纯CO_2的吸收量分别为1. 32,1. 57,1. 88 mol CO_2/mol ILs。温度升高和CO_2浓度降低均不利于CO_2吸收;烟气其他组分影响离子液体对CO_2的吸收性能,9%H2O/CO_2,5%O2/CO_2和9%H2O/5%O2/CO_2时,CO_2的饱和吸收量比纯CO_2分别降低了10. 2%,2. 5%和16. 7%。     

多活性位点季鏻盐型功能化离子液体的二氧化碳捕集行为

采用两步法合成了三种季鏻盐型功能化离子液体[a P4443][AA]([AA]=[Triz]、[2-Op]、[2-Np]),考察了温度、CO_2浓度和烟气组分(水分、氧气)对离子液体吸收CO_2性能的影响。结果表明,在30℃、常压条件下,三种离子液体都具有较高的CO_2捕集能力,[a P4443][Triz]、[a P4443][2-Op]和[a P4443][2-Np]对纯CO_2的吸收量分别为1. 32,1. 57,1. 88 mol CO_2/mol ILs。温度升高和CO_2浓度降低均不利于CO_2吸收;烟气其他组分影响离子液体对CO_2的吸收性能,9%H2O/CO_2,5%O2/CO_2和9%H2O/5%O2/CO_2时,CO_2的饱和吸收量比纯CO_2分别降低了10. 2%,2. 5%和16. 7%。     

离子液体吸收CO_2及其在沼气净化中的应用研究进展

本文综述了近年来离子液体用于CO_2吸收及用于CO_2/CH_4体系选择性吸收的研究状况,并对离子液体在沼气除杂净化中的应用前景进行了展望。     

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.     

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。     

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.     

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。