N,N-二甲基甲酰胺-三氯甲烷-水物系液液相平衡研究

为了获得制革DMF废水萃取回收工艺所需的基础数据,在常压20℃温度下,测定了三氯甲烷-N,N-二甲基甲酰胺-水拟三元体系的液液平衡数据,得到了三元体系平衡相图。实验数据点用NRTL模型进行了关联,得出了三氯甲烷-N,N-二甲基甲酰胺-水拟三元体系的模型参数。将实验数据与关联结果比较,表明NRTL模型能对该物系进行较准确关联。     

二乙氧基甲烷+水+甲苯或对二甲苯三元体系的液液相平衡

文章探讨了在常压下298.2和308.2 K时三元体系水+二乙氧基甲烷+甲苯和水+二乙氧基甲烷+对二甲苯的液液相平衡数据。根据实验数据对分配系数和分离因子进行了估算,其值均高于1,表明甲苯和对二甲苯作为萃取剂具有较好的萃取能力和较高的选择性;使用Othmer-Tobias和Hand经验方程来检验实验数据的准确性和可靠性,其线性相关的平方均大于0.990 0,表明数据具有较高的一致性;利用NRTL和UNIQUAC热力学模型对测量数据进行关联,相对均方根偏差(RMSD)均低于0.009 7,表明NRTL和UNIQUAC都能很好地关联三元体系的实验数据。     

正庚烷-甲苯-糠醛三元体系液液相平衡数据的测定与关联

在常压条件下测定了正庚烷-甲苯-糠醛三元体系在不同温度(293.15,303.15,313.15 K)下的液液相平衡数据。采用Othmer-Tobias方程对不同温度下的相平衡数据进行可靠性检验,相关性系数接近于1,表明实验数据存在较好的可靠性。用NRTL活度系数模型方程对实验数据进行关联,并使用Aspen Plus模拟软件回归计算出了该三元体系的二元交互作用参数,根据实验值和模拟值绘制不同温度下的三元相图。关联计算结果表明:NRTL方程对该三元体系适用性较好,实验值与模拟值之间的均方根偏差在1%以内,数据准确性高。根据实验数据计算出了萃取剂的选择性,为以后实验提供参考。     

水-醋酸-醋酸正丁酯三元体系液液平衡研究

文章用液液平衡装置在常压下，测定了水．醋酸-醋酸正丁酯三元体系40℃的液液相平衡数据。运用Othmer-Tobias方法对系线组成进行关联。由实验数据回归确定了NRTL、UNIQUAC以及修正的UNIFAC活度系数模型参数，并运用这些模型对体系相平衡进行了预测。将实验数据与关联结果比较，结果表明，三种方程均能较好地对溶液组成进行预测，其中UNIQUAC方程的拟合精度最好。     

N,N-二甲基甲酰胺-三氯甲烷-水体系液液相平衡数据的测定与关联

为获得进一步研究DMF废水萃取回收工艺所需的基础数据,利用液液平衡釜在常压下温度分别为30℃、35℃、40℃时进行N,N二甲基甲酰胺-三氯甲烷-水体系的液液相平衡实验,各物质的平衡组成由气相色谱分析,所得液液相平衡数据用NRTL和UNIQUAC模型进行关联,应用单纯形法求得相应的模型参数.计算值与实验值比较结果表明:NRTL与UNIQUAC模型的计算值与实验数据吻合良好,模型计算的总平均绝对误差分别为0.0032和0.0033,总平均相对误差分别为2.60%和2.97%.     

N-甲酰吗啉加水溶剂抽提芳烃的液液平衡

用液液平衡釜测定了常压 ,60℃下加水 N-甲酰吗啉和苯、甲苯、对二甲苯、正庚烷、甲基环己烷组分间 6个拟三元体系的液液平衡 ,得到了拟三元液液平衡体系的共轭相组成和分配曲线 ;实验数据用 UNIQUAC和NRTL模型进行了关联 ;用共轭相作图拟合法和模型参数推算法获得了各体系的褶点数据 ;并求得了溶剂对溶质的选择性和分配系数     

正十二烷-甲苯-苯酚三元体系液液相平衡数据的测定与关联

为获得研究中低温煤焦油典型组分之间的溶解特性以及指导煤焦油中酚类化合物提取所需的基础数据,在常压下测定了正十二烷-甲苯-苯酚三元体系在303.15、323.15和353.15 K时的液液相平衡数据,得到该体系三元相图。采用Othmer-Tobias方程对不同温度下的相平衡数据进行可靠性检验,相关性系数在0.992以上,表明实验数据可靠性较好,选取NRTL和UNIQUAC模型对所得液液平衡数据进行关联,获得了不同温度下模型参数,计算值与实验值比较表明:NTRL和UNIQUAC模型的计算值与实验值吻合良好,其相对均方根偏差均在1%以内。     

棕榈酸异丙酯+异丙醇+水三元物系液液相平衡数据的测定与关联

用平衡法测定测定了常压下棕榈酸异丙酯+异丙醇+水三元混合物体系的液液相平衡数据。通过AspenPlus软件,用NRTL和UNIQUAC活度系数模型对该三元物系的液液相平衡实验数据进行了关联,回归得到了该三元物系的二元交互参数,并用回归得到的模型参数,对该三元物系的液液相平衡进行了关联,将计算值与实验值进行比较,结果表明UNIQUAC模型能够很好的关联实验数据,其平均相对误差ARD小于NRTL模型的ARD。为棕榈酸异丙酯的分离提纯和工程设计提供了必不可缺少的工程基础数据。     

乙腈-正丙醇-N,N-二甲基甲酰胺体系的等压汽液平衡

用改进Rose釜测定了101.3 kPa下乙腈-正丙醇、乙腈- N,N-二甲基甲酰胺(DMF)、正丙醇-N,N-二甲基甲酰胺(DMF)、乙腈-正丙醇- N,N- 二甲基甲酰胺(DMF)体系的等压汽液平衡数据,并通过了热力学一致性检验,用Wilson、NRTL模型对三个二元体系的汽液平衡数据进行关联,效果良好.由关联得到...     

邻甲酚-间二甲苯-乙二醇液液平衡数据的测定与关联

乙二醇可从含芳烃组分油品中选择性萃取酚类，为支撑焦化含酚油中的酚类化合物萃取分离新工艺开发，针对其组分特点，在现有相平衡数据基础上选定代表物，利用液液平衡釜法测出常压下303.15、313.15和323.15 K时邻甲酚-间二甲苯-乙二醇体系液液相平衡数据，并利用Othmer-Tobias方程、Hand方程、Bachman方程分别进行实验数据可靠性检验，其线性相关系数的平方均大于0.99。同时分别用NRTL和UNIQUAC活度系数模型对实验数据进行关联，回归得到不同温度下的模型参数，模型计算值与实验数据对比后发现其均方根偏差小于1.8%，说明NRTL和UNIQUAC模型均可较好地描述该三元体系相平衡行为。     

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.     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.