一种新的NMR法测定溶液中碱土金属混合物的方法原理

本文研究了碱土金属离子-锶、钡及钙可以形成在NMR标尺上是稳定配合物的条件。找到了最适合得到这样的配合物的配体-C222穴醚。研究并归属了碱土金属离子以及碱金属-钠、钾及锂配合物在氯仿中的¹³C NMR谱。检测出了可用于分析自由配体及其与碱土金属配合物的¹³C NMR信号,还研究了不同比例混合物的碱土金属及碱金属在氯仿中的¹³C NMR谱,得到了当自由配体过量时在钡、钙及锶每种金属浓度为1×10^-3M的谱中可观测到相当于自由配体及每种离子配合的配体的分立信号。这些信号的积分值的精度可以定量地表征金属离子的浓度,所得结果为首次观测到的。它可以作为用¹³C NMR波谱建立新的无机分析方法。文中并阐明了作溶液中碱土金属混合物NMR测定方法的具体条件,并讨论了将这一方法扩展到包括一系列碱金属在内的更复杂的混合物的可能性。试验在VARIAN XL-200波谱仪上进行。     

CHARACTERIZATION AND CATALYTIC BEHAVIOR OF WATER-SOLUBLE PHOSPHINE RHODIUM (I) COMPLEX

IntroductionInhomogcncouscatal}-sis*arccurrentproblcmisthcseparationofthcorganicproductsfromtheactivecatal}'stThcapplicationoft`atersolubletransitionmctalcomplcxcsf0rcataI}ticrcactionshasrcccntl}'attractcdconsidcrablcattcntio.lI~3l.Thcx"atcr-solubleligandsarcslightl}'solublcinorganicmcdia-allot"ingthccatal}'sistobccarricdoutinat\"o-phascs}'stcm.Catal\'strccovcry'isthuscasil}'achievcdb}'dccantationandseparationofthctx"ophascs.Thctris(sodiumm-sulfophcn}-l)-phosphinc,P(m-C6fuS03Na)3(abbr.asTP…     

空气瓶—树脂试剂法鉴定微量有机物中氮,硫和卤素

制备了7种树脂试剂。采用空气瓶预分解徽量有机物,配合树脂试剂法鉴定氮、硫和卤素。检出限(μg)分别为:NO_3- 0.023,SO_4~(2-)1.2,F-0.03,Cl-2.1,Br-0.05及I~-0.9。并研究了氮的“假检出”问题。     

Thermal and crystallization studies of nano-hydroxyapatite reinforced polyamide 66 biocomposites

The thermal and crystalline behaviour of nano-hydroxyapatite (n-HA) reinforced polyamide 66 (PA66) biocomposites was studied by thermogravimetry (TG) and differential scanning calorimetry (DSC). The thermal properties of PA66 and n-HA/PA66 composites were analysed by TG. The effect of hydroxyapatite on the melting and crystallization of PA66 was evaluated by DSC. DSC measurements exhibited an increase in the crystallization temperature, however, decrease in crystallinity with the addition of n-HA to the PA66 matrix, which was attributed to the hydrogen bonds between the n-HA surface and polyamide 66 molecules. With increase of n-HA content, the melting peak of the PA66 component shifted to higher temperature, suggesting constrained melting. The addition of n-HA to PA66 played the role of nucleating agent and enhanced the crystallization rate. Non-isothermal parameter a measured by Liu method varies from 1.13 to 1.18, from 1.02 to 1.07, and from 1.18 to 1.21 for PA66, 30 wt% n-HA/PA66 and 40 wt% n-HA/PA66, respectively, and the values of K_(T) systematically increase with rise in relative degree of crystallinity.     

Synthesis of graphite nanosheets/AgCl/polypyrrole composites via two-step inverse microemulsion method

An effective process for the synthesis of graphite nanosheets/AgCl/polypyrrole (NanoGs/AgCl/PPy) composites was developed. NanoGs were prepared by treating the expanded graphite with sonication in aqueous alcohol solution. Then nanocomposites were fabricated via in situ polymerization of pyrrole in the presence of NanoGs and AgCl particles through two-step sequentially inverse microemulsion method. The nanoscale dispersion of NanoGs and AgCl particles was evidenced by the SEM and TEM examinations. From the thermogravimetric analysis, the introduction of inorganic nano-AgCl and NanoGs exhibited a beneficial effect on the thermal stability of pure PPy. According to the four-point-probe test, the conductivity of the final NanoGs/AgCl/PPy composites was dramatically increased compared with pure PPy.     

Study on the Phase Behavior of Supercritical CO2／Dynol—604／Water System and Solubilization of Methyl Orange in the Microemulsions

It was found that Dynol-604, a non-fluorous and no silicon-containing nonionic surfactant,was soluble in supercritical (SC) CO2. The phase behavior of SC CO2/Dynol-604/water system was studies. The results showed that one-phase water-in-CO2 microemulsions could be fromed. The solubilization of methyl orange in the microemulsions proved further the existence of water domain in the microemulsions.     

Kinetics of the Esterification Reaction Catalyzed by Lipase in W／O Microemulsions of Alkyl Polyglucoside

A novel kinetic mechanism of esterification reaction of 1-hexanoic acid with 1-butanol,catalyzed by lipase, was studied in water-in-oil microemulsions. The microemulsions were formed by alkyl polyglucoside C10G1.54/1-butanol/cyclohexane/phosphate buffer solution. The restult shows that when the ratio of mol concentration of 1-butanol to 1-hexanoic acid is about 3.0,the initial rate V0 get the maximum values. This phenomenon was explained by the modified fishlike phase diagrams.