气相色谱用微波诱导氩等离子体光离子化检测器的研究

本文报道了以Surfatron 表面波为激发器件的微波诱导氩等离子体光离子化检测器,以氩气为载气和工作气体,研究了三种不同类型检测器的结构性能, 通过测量检测器的工作参数及苯的检出限等,对检测器的基本特性和离子化机理进行了探讨,并应用于实际样品分析,结果令人满意     

微波辐射下芳醛与5, 5-甲基-1, 3-环己二酮的固相和液 相反应

芳醛(1)与5,5-二甲基-1,3-环己二酮(2)在固相条件下,经微波辐射得到3,而在乙二醇溶剂中,经微波辐射得到4,产率接近定量。     

微波辐射下4-芳基-7,7-二甲基-5-氧代-3,4,5,6,7,8-六氢 香豆素的合成及其晶 体结构

芳醛(1),5,5-二甲基-1,3-环已二酮(2),麦氏酸(3)经微波辐射3～5min,不需任何催化剂,得到4-芳基-7,7-二甲基-5-氧代-3,4,5,6,7,8-六氢香豆素(4)。产物的结构经红外、核磁、元素分析及X-射线衍射法确证。对反应过程提出了可能的机理。     

微波辐射一步法合成吡喃和吡喃[2, 3-c]吡唑衍生物

芳醛、丙二腈与5,5-二甲基-1,3-环己二酮或3-甲基-1-苯基-2-吡唑啉-5-酮在乙醇溶剂中用哌啶作催化剂,经微波辐射一步合成了2-氨基-3-氰基-4-芳基-7,7-二甲基-5-氧代-5,6,7,8-四氢苯并吡喃和6-氨基-5-氰基-4-芳基-1,4-二氢吡喃[2,3-c]吡唑,反应在2～12min内完成,产率53%～91%。     

Plasma catalytic reaction of natural gas to C2 product over Pd-NiO/Al2O3 and Pt-Sn/Al2O3 catalysts

The decomposition of natural gas over Pd-NiO/Al₂O₃ and Pt-Sn/Al₂O₃ is carried out in a microwave catalytic reaction at room temperature. The decomposition of methane is caused by collision by excitation of unstable electronic state. Measuring the flow rate and plasma power can provide kinetic data and indicate the mechanism. The conversion of C₂ products increases from 47 to 63.7% in the microwave plasma catalytic reaction with electric field. Comparing the activities of catalysts, Pd-NiO/Al₂O₃ bimetallic catalyst is more active than Pt-Sn/Al₂O₃ catalyst because of modification of the surface of catalysts by carbon formation. The kinetic modeling of plasma of methane conversion seems related to the power of the electric discharge. It was also revealed that proper coking or polymeric carbon formation improves the catalytic activity; therefore, the conversion of methane may increase over Pd-Ni/Al₂O₃ catalyst in the plasma system.     

POLYMERIZATION OF N,N′-(PYROMELLITOYL)-BIS-L-LEUCINE DIACID CHLORIDE WITH HYDANTOIN DERIVATIVES BY MICROWAVE IRRADIATION

Facile and rapid polycondensation reactions of N,N′-(pyromellitoyl)-bis-L-leucine diacid chloride 1 with eight different derivatives of hydantoin compounds 2a-h were developed by using a domestic microwave oven in the presence ora small amount of polar organic medium such as o-cresol. The polycondensation reactions proceeded rapidly, compared with the conventional solution polycondensation, and was completed within 7-10 min, producing a series of novel optically active poly(amide-imide)s 3a-h with high yield and inherent viscosity of 0.35-0.65 dL/g. All of the above polymers were fully characterized by FT-IR, elemental analyses, inherent viscosity (ηiaa), solubility test and specific rotation. Some structural characterization and physical properties of these optically active poly(amide-imide)s are reported.     

微波固相法合成层状磷锑酸钾化合物

应用微波合成技术, 以石墨或三氧化二铁为加热介质, 合成了两种新的层状磷锑酸钾: KSbP2O8, K3Sb3P2O14。与传统固相反应相比较(典型合成条件为:950~1000℃下、24h), 微波法可在微波辐射下(2.45 GHz), 仅在40~90分钟内使反应完成。在详细研究相转变的同时, 对微波在固相合成中的作用进行了初步的讨论。     

Microwave-enhanced dechlorination of chlorobenzene

- Heterogeneous liquid-phase dechlorination of chlorobenzene over supported palladium-based catalysts to form benzene was examined using microwave and conventional heating methods. The reaction was carried out in a solution of NaOH in 2-propanol at atmospheric pressure and reflux temperature (approx. 83°C). Two types of commercial aluminium-silicate and -alumina-supported catalysts have been tested. The results obtained under microwave (MW) and conventional (CH) conditions were compared with respect to the rate enhancement, selectivity and catalyst activity. The sole product of the chlorobenzene dehalogenation was benzene. The effect of the addition of NaOH has been analysed for the neutralisation of HCl.     

微波促进下1-芳甲酰基-4-（2’-苯并呋喃甲酰基）氨基硫脲及其衍生物的合成

微波辐射条件下，首先由2-苯并呋喃甲酰氯在相转移条件下依次与硫氰酸铵和 芳甲酰肼反应合成了一系列1-芳甲酰基-4-（2’-苯并呋喃甲酰基）氨基硫脲，进 一步在微波辐射的条件下由这些氨基硫脲分别与碘酸钾、醋酸或醋酸汞等试剂作用 高产率地制得了1-芳甲酰基-4-（2’-苯并呋喃甲酰基）氨基脲、2-芳基-5-（2’- 苯并呋喃甲酰胺基）-1，3，4-噻二唑和2-芳基-5-（2’-苯并呋喃甲酰胺基）-1， 3，4-（口恶）二唑。     

微波作用下1，5－苯并硫氮杂Zhuo－α－氨基－β－内酰胺衍生物的合成及晶体结构

甘氨酸N－端保护试剂邻苯二甲酰亚胺乙酰氯、1，5－苯并硫氮杂Zhuo在三乙 胺的存在下，用微波辐射合成了5个1，5－苯并硫氮杂Zhuo-α－氨基－β－内酰胺 衍生物，反应在6min内完成，产率较为满意。X射线衍射分析确定了产物的立体结 构，结果表明，微波辐射下的反应为立体 专一性反应，β－内酰胺环上的两个取 代基位于环的同侧为顺式。