祥鹄微波合成仪

立了儿童玩具中的壬基酚和辛基酚的高效液相色谱串联质谱分析方法。样品用甲醇微波提取，采用ZORBAX Eclipse Plus C18色谱柱，以甲醇-水为流动相，等梯度洗脱分离后，串联四极杆质谱多反应监测方式检测，以保留时间和相对离子丰度(离子比率)定性，外标法定量。在优化条件下，该方法5 min内即可完成待测物的分析。壬基酚和辛基酚在0.001~0.10 mg/L的范围内线性关系良好，相关系数大于0.999，方法的定量下限为0.02 mg/kg。在加标水平为0.02、0.2、2.0 mg/kg时，待测物的平均加标回收率为76.8 %~99.0 %，相对标准偏差(n=6)小于6.6 %。该方法准确、快速、灵敏，适用于儿童玩具中的壬基酚和辛基酚的快速确认和定量检测。

Abstract An organic–inorganic poly(3,4-ethylenedioxy-thiophene) (PEDOT)/RuO2·xH2O nanocomposite (approxi-mately 1 wt.% RuO2) has been successfully prepared for the first time under microwave irradiation within 5 min with power 900 W via in situ chemical polymerization. The morphology and structure of the resultant material is characterized by transmission electron microscope and Fourier transform infrared. Moreover, the electrochemical properties of the synthesized nanocomposite can be controlled by adjusting the annealing temperature, which is definitely illustrated by cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectra. Electrochemical data have shown that the PEDOT/RuO2·xH2O nanocomposite annealed at 150 °C possesses the most favorable charge/discharge ability with a specific capacitance of 153.3 F g?1at a current density of 150 mA g?1 and the high efficient utilization of PEDOT at various current densities. Furthermore, such composite has a less capacitance degradation of 23.8% after 1,000 continuous cycles. The improved electrochemical performance are mainly attributed to the large electroactive surface of nanocomposite and the existence of amorphous RuO2·xH2O particles as well as a synergistic effect of the polymer PEDOT and annealed RuO2·xH2O. Thus, the PEDOT/RuO2·xH2O nanocomposite annealed at 150 °C can act as a promising electroactive material for supercapacitor application

通过 298、308 K 和 318 K 温度下的平衡吸附实验和 298 K 下的动力学实验 ，考察了 HPD－100大孔 吸 附 树 脂 吸 附 水溶 液 中 葛 根 异 黄 酮 的 热 力 学 和 动 力 学 过 程. 分别用 Langmuir 和 Freundlich 等温方程对热 力学数据进行拟合并计算得到各热力学参数 ，结果表明，HPD－100 树脂对水溶液中葛根异黄酮的吸附可用 Freundlich 吸附模型描述（相关系数大于 0．992），吸附为不均匀表面的多分子层吸附. 负 的 热 力 学 焓 变 和吉 布斯自由能证实反应为可自发进行的放热过程 ，低温有 利 于 吸 附 的 进 行 ，负 的 熵 变说 明 吸 附 后 体 系 的混乱 度降低. 动力学实验结果显示，吸附为快速过程. 通过拟一级 ／ 二级动力学方程的拟合可知，HPD－100吸附水 溶液中葛根异黄酮的过程遵循拟二级吸附动力学（相关系数大于 0．99）规律. 吸附速率随异黄酮初始浓度升 高而显著降低.

相比于索氏提取，时间更短，产率更高。 Abstract: The longan (Dimocarpus Longan Lour.) peel was extracted with 95% ethanol employing microwave-assisted extraction and Soxhlet extraction method, the total phenolic content of microwave-assisted extract of Langan peel (MEL) and Soxhlet extract of Langan peel (SEL) reached 96.78 mg/g and 90.35 mg/g dry weight, respectively, expressed as pyrocatechol equivalents, which were quanti?ed using Folin–Ciocalteu reagent. Subsequently, antioxidant properties of two extracts were investigated employing various established systems in vitro including 2,20-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, hydroxyl radical scavenging assay using a new resonance scattering (RS) method, reducing power and total antioxidant capacity. MEL and SEL showed excellent antioxidant in all test systems compared to synthetic antioxidant 2,6-di-ter-butyl-4-methylphenol (BHT) and the antioxidant activities of MEL were all superior to those of SEL. Furthermore, the suitability of MEL and SEL as substitute of BHT were determined in peanut oil, and the decrease of lipid oxidation were monitored using thiobarbituric acid-reactive substances (TBARS) assay. MEL and SEL treatment signi?cantly (P < 0.05) reduced lipid oxidation in peanut oil compared to the control. No signi?cant differences (P ? 0:05T in lipid oxidation were detected between MEL, SEL and BHT samples of peanut oil.