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991.
Introduction The salting out effect in the systems of aliphatic al-cohol-water is of industrial interest. The addition of or-ganic solvents to the aqueous solution of a salt normally decreases the solubility of the salt. So the method can be used for salting-out of inorganic salts to improve yield and purity.1-3 However, the phase diagrams of the inves-tigated systems are required as basic data. There are lots of aliphatic alcohol-water systems having been deter-mined. The 1-butanol-water-Na…  相似文献   
992.
3,3′,5,5′-Tetramethylbenzidine(TMB)-H2O2-horseradish peroxidase(HRP) voltammetric enzyme linked immunoassay system1 has very high sensitivity, low detection limit and wide detection range for the determination of some plant viruses. However, the understanding of the mechanism of HRP catalyzed by H2O2 oxidizing TMB in this system is of significance. In the previous paper, we have reported the spectroelectro- chemical study of TMB on SnO2: F film optically transparent electrode in the …  相似文献   
993.
Thickness and stability of films formed by different surfactants are studied by means of thin film balance (TFB) technique to observe the formation and stability of the films. It is demonstrated that stable Newton black films (NBFs) can be easily obtained with non-ionic surfactants (C12E5, C12G2) than ionic surfactants (C12TAB, C16TAB). Common black film (CBF) was obtained with C16TAB at 5×10-3 mol/L, while the film of C12TAB is unstable. It has been demonstrated that the horizontal forces should also be taken into consideration for explaining film stability.  相似文献   
994.
A new MEEKC method assisted with pressure-driven mobile phase was presented for the separation of felted explosives. Microemulsion solution was composed of 80 mmol/L heptane-120 mmol/L SDS (sodium dodecyl sulphate)-900 mmol/L butanol-10 mmol/L borate at pH 9.4 and a pressure-driven flow of 0.020 mL/min under 1.3 MPa was employed to manipulate the separation. Explosives HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane) and TATB(triamino-trinitrobenzene), which were felted on fluorine rubber F2311 (polytrifluorochlorethylene and polyvinylidene fluoride 1/1 co-polymerization) and F2314 (polytrifluorochlorethylene and polyvinylidene fluoride 4/1 co-polymerization) were well separated with very good peak shapes.  相似文献   
995.
用X-射线光电子能谱对3种植物基活性炭材料:椰壳活性炭 (CAC4)、剑麻茎基活性炭(SSAC)和剑麻基活性碳纤维 (SACF) 的表面化学结构进行了表征,并研究和对比了它们的吸附性能,包括对碘、苯酚和亚甲基蓝的液相吸附性能,对有机蒸汽的吸附性能以及对Au3+的还原吸附性能等。结果表明,3个样品表面均含有多种含氧官能团,吸附能力SACF>SSAC> CAC4。样品的吸附性能主要取决于自身孔结构,与其表面化学结构也有密切的关系。  相似文献   
996.
1. INTRODUCTION The serious environment pollution and natural resources waste is imperiling human existence and development. To counter the exhaustion and dilution of natural resources, and to prevent environment from further pollution, it is their duty …  相似文献   
997.
本文合成了九种不同取代基的苯基四氟硼酸重氮盐及其与18-冠醚-6形成的分子络合物, 考察它们的低频红外光谱, 讨论这类络合物的成键状况。  相似文献   
998.
Enantiomeric separation of epinephrine and salbutamol was investigated by micellar electrokinetic chromatography employing β-cyclodextrin as chiral additive in ammonium chloride-ammonia solution. The analytes were detected by electrochemistry using gold microelectrode at 0.65 V versus SCE reference electrode. The effects of detection potential,concentration of β-cyclodextrin, concentration of sodium dodecyl sulfate, pH value of electrolyte and applied voltage were discussed.  相似文献   
999.
The crystal structure of [CoCl ( C7H5N2CH2COPh)4] Br has been determined by means of X-ray crystallography. The molecular structure consists of a discrete [CoCl ( C7H5N2CH2COPh)4] ^ cation and one Br^- anion, in the [CoCl ( C7H5N2CH2COPh)4]^ cation, the coordination geometry of the central Co atom is square-pyramidal with four tertiary N atoms of benzimidazole from four α-( benzimidazol-1-yl) -hypnone ligands in the basal position and one chloride anion in the apical position. In the solid state, [CoCl ( C7H5N2CH2COPh)4]^ and Br^- anion possess intermolecular and intramolecular interactions, which stabilize the crystal structure. The characterization of the title compound were also carried out by using elemeutal analysis, FTIR, UV spectrometries and TG-DSC.  相似文献   
1000.
本文介绍采用毛细管气相色谱-质谱法研究了甘肃敦煌栽培的茴霍香精油的化学成分。色谱分离出30多个组分,质谱鉴定了25种化合物,占色谱流出峰总面积的97.87%。其中有19种化合物为该植物化学成分的首次报道。异薄荷酮(35.22)、茴香脑(24.30%)和长叶薄荷酮(16.66%)为该精油的主要成分。  相似文献   
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