由肟一锅法合成乙酰苄胺衍生物

肟与锌粉/醋酸反应,得到的中间产物与醋酸酐反应,一锅两步法高收率地合成了标题化合物.该合成方法操作简单,无须使用昂贵的催化剂,对环境友好,收率高达83%～93%.     

聚氨酯分子印章材料的制备及其性能研究

以聚丙醚(PPG)和甲苯二异氰酸酯(TDI)为原料,20%的二月桂酸二丁基锡邻苯二甲酸二甲酯溶液为催化剂,3,3′-二氯-4,4′-二氨基二苯甲烷(MO-CA)和三羟甲基丙烷(TMP)作混合交联剂,通过浇注法得到用于极性分子印章制备的聚氨酯弹性体材料,其优化配方为:PPG,TDI和交联剂的摩尔比为1∶2.5∶0.90,交联剂中MOCA与TMP的摩尔比为5∶1。这种聚氨酯材料,在乙腈或乙醇中浸泡2h,溶胀体积变化在0.5%以下;其机械硬度、抗拉强度和50%的压缩复原率分别为72HA、3.57MPa和99.6%。     

四(4-羟基-3-苯偶氮基)苯基卟啉的合成、表征及光谱性能

以苯胺和对羟基苯甲醛为原料合成偶氮醛,并进一步与吡咯缩合得到一种新型的偶氮卟啉。通过元素分析、质谱、^1HNMR、UV-Vis表征了其结构。探讨了其荧光性能。通过与四对羟基苯基卟啉的荧光性能的对比,发现有较大程度的荧光猝灭。可能是偶氮苯基与卟啉环相互作用发生分子内电子转移的结果。     

反相高效液相色谱内标法测定环己烷空气氧化产物中二酸类物质

采用反相高效液相色谱内标法对环己烷空气氧化制备己二酸生产工艺中的己二酸及主要副产物戊二酸、丁二酸、丙二酸进行了定性、定量分析。其优化后的色谱条件为色谱柱Zorbax eclipseXDB-C8柱(150mm×4.6mm,ф5μm),以庚二酸为内标物,流动相为甲醇和磷酸水溶液(pH=2.2),柱温为30℃,流量为0.6ml/min,VWD检测波长为206nm。标准样品均在0.0015～0.03mol/l范围内呈良好的线形关系(r>0.9997),平均回收率为99.32%～100.68%,RSD为0.7286%～0.8946%(n=6)。该方法样品不需预处理,分析时间较短,重现性好,准确可靠。     

基于改进简化实频技术的超宽带功率放大器设计

该文提出了一种基于改进简化实频算法的跨多倍频超宽带功率放大器.结合负载牵引技术,分析晶体管负载端的最优阻抗值变化.通过改进简化实频法中的优化目标和误差函数,对频段内选取多个频点的最优阻抗进行分析,设计并优化出了功率放大器的输出匹配电路,提高了功放的工作带宽.测试结果显示,在0.5～2.7?GHz频段内,饱和输出功率达到42.5?dBm,饱和漏极效率为64％～75％.     

大学有机化学实验课程教学探讨

本文对有机化学实验教学的实验内容体系、实验教学方法以及实验教学中的绿色化学改革进行了探讨,认为在实验内容上应根据教学目的整合实验内容,多渠道训练学生的基本操作技能,在教学过程中充分调动学生的主观能动性、积极性和创造力.     

Preparation of p-menthane hydroperoxide from p-menthane in presence of metalloporphyrins

The aerobic oxidation of p-menthane to p-menthane hydroperoxide (PMHP) in the presence of metalloporphyrins was investigated in an intermittent mode under an atmospheric pressure of air. Several important reaction parameters, such as the structure of metalloporphyrin, the air flow rate, and the temperature, were studied. The preliminary mechanism of the aerobic oxidation of p-menthane catalyzed by metalloporphyrins was also discussed. The results show that the reaction is greatly accelerated by the addition of metalloporphyrins at very low concentration, in terms of both the yield and formation rate of PMHP, and the high selectivity of PMHP is maintained during the reaction. Temperature of 120 ℃ and reaction time of around 5 h are the optimal conditions for the best result in the presence of 0.06 mmol/L monomanganeseporphyrins ((p-Cl)TPPMnCl). Furthermore, the yield of PMHP is increased remarkably when the reaction is carried out under programmed temperature compared with the constant temperature. When the reaction is catalyzed by 0.06 mmol/L((p-Cl)TPPMnCl) at the air flow rate of 600 mL/min and 120 ℃ for 4 h, and then the temperature is reduced to 110 ℃, for another 4 h, the yield of PMHP reaches 24.3%, which is higher than that of the reaction at a constant temperature of 120 ℃ or 110 ℃ for 8 h.     

高变异药物醋酸阿比特龙片人体生物等效性评价

目的: 评价高脂餐后单剂量口服高变异药物醋酸阿比特龙片受试制剂与参比制剂在中国健康人体中的生物等效性。方法: 本研究采用随机、开放、双序列、四周期重复四交叉试验设计,共入组健康男性受试者32人,单剂量高脂餐后口服受试制剂和参比制剂醋酸阿比特龙片250 mg。采用LC-MS/MS测定给药后血浆中阿比特龙药物浓度。使用WinNonlin 7.0计算药动学参数并用SAS 9.4软件进行生物等效性评价。结果: 受试制剂和参比制剂中阿比特龙C_max分别为(238.0±108.6）、(220.1±96.9) ng/mL,T _max分别为2.0(1.0-4.0)、2.0(1.0-5.0) h,t _1/2为(13.1±2.6)、(13.0±2.9) h,AUC _0-t 分别为(615.2±226.3)、(589.4±210.1) h·ng·mL^-1,AUC _0-∞分别为(618.7±227.7)、(592.8±211.6) h·ng·mL^-1。受试制剂和参比制剂阿比特龙的AUC _0-t 、AUC _0-∞和C _max的几何均数比值（T/R）的90%置信区间均在80.00%至125.00%范围内。结论: 醋酸阿比特龙片受试制剂与参比制剂在餐后给药时具有生物等效性。     

Effects of Oxygen Transfer Limitation and Kinetic Control on Biomimetic Catalytic Oxidation of Toluene

Under oxygen transfer limitation and kinetic control, liquid-phase catalytic oxidation of toluene over metalloporphyrin was studied. An improved technique of measuring dissolved oxygen levels for gas-liquid reaction at the elevated temperature and pressure was used to take the sequential data in the oxidation of toluene catalyzed by metalloporphyrin. By this technique the corresponding control step of toluene oxidation could be obtained by varying reaction conditions. When the partial pressure of oxygen in the feed is lower than or equal to 0.070 MPa at 463 K, the oxidation of toluene would be controlled by oxygen transfer, otherwise the reaction would be controlled by kinetics. The effects of both oxygen transfer and kinetic control on the toluene conversion and the selectivity of benzaldehyde and benzyl alcohol in biomimetic catalytic oxidation of toluene were systematically investigated. Three conclusions have been made from the experimental results. Firstly, under the oxygen transfer limitation the toluene conversion is lower than that under kinetic control at the same oxidation conditions. Secondly, under the oxygen transfer limitation the total selectivity of benzaldehyde and benzyl alcohol is lower than that under kinetic control with the same conversion of toluene. Finally, under the kinetics control the oxidation rate of toluene is zero-order with respect to oxygen. The experimental results are identical with the biomimetic catalytic mechanism of toluene oxidation over metalloporphyrins.     

有机化学“三结合”模式教学在人才培养中的应用

本文介绍了湖南大学有机化学与实验课程在人才培养过程中开展的将理论教学、实验教学与科学研究紧密结合,将培养学生基础知识与技能、基本知识转移能力与研发能力相结合,将国家教学基地与科研机构、企业公司相结合的"三结合"模式,并研究了该模式在人才培养中的作用。事实证明"三结合"新体系在人才培养中发挥了重要作用。