尿素-氯化胆碱低共熔溶剂中均苯四甲酸二酰亚胺的清洁合成

研究了尿素-氯化胆碱DES中由均苯四甲酸二酐制取均苯四甲酸二酰亚胺工艺,考察了反应时间、反应温度及DES与均苯四甲酸二酐PMDA比例对产物收率的影响,通过响应面实验和Design-Expert中岭回归分析对反应条件进行了优化,得出最佳反应温度为130℃、反应时间4 h、DES与均苯四甲酸二酐质量比8.1:1,最终产物收率可达93.0%。采用红外光谱、紫外-可见光光谱仪、熔点仪、XRD对合成产物进行了表征,证明产品为均苯四甲酸二酰亚胺。基于尿素-氯化胆碱低共熔溶剂分解动力学,提出了简单的反应机理。尿素-氯化胆碱DES可起到溶剂、原料兼催化剂三重作用,且可重复使用,实现了均苯四甲酸二酰亚胺的绿色合成。     

基于高效回收废旧锂离子电池正极材料的低共熔溶剂的筛选

针对废旧锂离子电池(LIBs)回收过程中产生的二次污染及高能耗等问题, 提出了一种绿色高效浸出废旧LIBs正极材料中有价金属的新方法. 以氯化胆碱和不同的氢键供体(草酸、 丙二酸、 戊二酸和苯磺酸)为原料, 合成了氯化胆碱/酸二元低共熔溶剂(DES)、 氯化胆碱/酸/水和氯化胆碱/酸/乙醇等三元DES. 通过傅里叶变换红外光谱(FTIR)和核磁共振波谱(NMR)表征了氯化胆碱和酸之间氢键的形成过程, 探究了DES中羧酸的烷基链长、 酸性大小以及添加水和乙醇组分对浸出废旧LiCoO₂正极材料的影响. 研究结果表明, 羧酸烷基链长的增加会使DES的浸出能力下降; 酸的酸性大小不能作为溶解金属氧化物能力强弱的主要依据; 加入等摩尔量的水对DES的浸出效率影响较小, 而等摩尔量加入无水乙醇会影响DES的氢键结构, 对浸出结果影响较大. 筛选出氯化胆碱/苯磺酸/乙醇DES作为废旧LiCoO₂绿色高效的浸出剂, Li和Co的浸出效率分别高达98.6%和95.2%.     

氯化胆碱/尿素和氯化胆碱/甘油的性质与应用

作为绿色溶剂,离子液体在化学和物理学科引起广泛关注.低共融溶剂,如氯化胆碱/尿素和氯化胆碱/甘油,不仅被认为是一类新型的离子液体,还具有价格低廉、环境友好及合成简便等优势.为了促进氯化胆碱/尿素和氯化胆碱/甘油这两种低共融溶剂的应用,本文考察了氯化胆碱/尿素和氯化胆碱/甘油的微观结构、物理化学性质及水分对其物性的影响,并将其与传统离子液体进行了比较.此外,还分析了氯化胆碱/尿素和氯化胆碱/甘油在摩擦学及CO2分离中的潜在应用.已有研究结果表明,氯化胆碱/尿素和氯化胆碱/甘油有希望应用于摩擦学及CO2分离中,但是在大规模工业应用之前依然存在很多不确定性和瓶颈,还需要进一步在其纳米结构、实验测定及模型等方面进行研究.     

铜负载聚酰亚胺光-芬顿降解甲基橙研究

采用尿素-氯化胆碱DES辅助制备了铜负载的聚酰亚胺催化剂,并将其应用于光-芬顿降解甲基橙染料。其中,尿素-氯化胆碱DES可作为溶剂和去质子化试剂,使得铜能更好地负载到聚酰亚胺上。同时,通过SEM、XRD、红外光谱、EDS、TEM、XPS等手段对催化材料进行了表征,验证了铜的负载。进一步探究了催化剂用量、H₂O₂用量、pH、光照强度、初始浓度等条件对最终降解效率的影响,通过正交试验对实验条件进一步优化,得出甲基橙初始浓度为10 mg·L^-1、pH=3、光照强度500 W、H₂O₂加量0.15 mL、催化剂用量为0.15 g时,可达到甲基橙的几乎完全降解。     

基于低共熔溶剂的分散液液微萃取/超高效液相色谱-串联质谱法测定马肉中非甾体抗炎药

采用氯化胆碱和苯酚合成低共熔溶剂(DES),以其为萃取剂建立了分散液液微萃取(DLLME)结合超高效液相色谱-串联质谱(UPLC-MS/MS)测定马肉中10种非甾体抗炎药的方法.优化了提取溶剂、萃取剂、分散剂和盐的加入量等条件,最佳萃取条件为:以氯化胆碱和苯酚(比例为1 ∶ 2)合成的低共熔溶剂为萃取剂,马肉样品经5 ...     

憎水性低共熔溶剂的合成及在萃取分离领域中的应用研究进展

综述了憎水性低共熔溶剂合成及应用的国内外研究状况。结合萜烯、季铵盐、长链脂肪酸和氯化胆碱等几大类憎水性DES的分子结构特点,比较并分析了氢键供体和氢键受体中不同官能团对亲脂性和憎水性的贡献。简述了不同系列憎水性DES的熔点、密度、粘度、折光率或电导率以及在水中的溶解性等理化性质特点。评述了不同系列憎水性DES在萃取水溶液中金属离子、农药和染料,植物中生物活性化合物以及分析化学中液-液微萃取制样等诸多萃取领域的应用技术状况和发展潜力。     

低共熔溶剂辅助水热法合成分层球状微/纳米ZnO晶体及其光催化性能

使用尿素-氯化胆碱低共熔溶剂(UCC-DES),采用水热合成和反溶剂(乙醇)法,以化工材质ZnO粉末为原料制备了分层的球状微/纳米ZnO晶体.分析了反应时间、反溶剂的种类和含量对ZnO晶体形貌的影响以及ZnO晶体析出的原因.并将制备的分层球状ZnO微/纳米晶体应用于光催化降解甲基橙.结果表明,制备的ZnO晶体对甲基橙有良好的光催化降解性能.     

塑料膜中塑化剂(DEHP)低共熔溶剂液相微萃取的开路电位和PM7半经验分子轨道法研究

开路电位法研究了邻苯二甲酸二(2-乙基)己基酯在尿素-氯化胆碱碳糊电极表面上微萃取行为。在6000s的饱和萃取时间下的开路电位差与邻苯二甲酸二(2-乙基)己基酯在萃取溶液中的浓度呈反比,其表观一级动力学常数为6.35×10-4s~(-1),可应用于不同塑料膜中邻苯二甲酸二(2-乙基)己基酯的相对含量的检测。基于DES与DEHP相互作用的分子簇模型,半经验分子轨道量子化学方法计算了分子簇的热力学参数,表明DES与DEHP相互作用形成分子簇过程为自发过程,三个DES可以支撑一个DEHP分子,为DES萃取有机酯类化合物提供理论依据。     

磺酸功能化胆碱催化合成14-芳基-14H-二苯并[a,j]氧杂蒽衍生物

以氯化胆碱为原料,制备了磺酸功能化胆碱催化剂,在水介质中催化芳香醛和2-萘酚反应合成了一系列14-芳基-14H-二苯并[a,j]氧杂蒽衍生物,产率达85～97%。该催化剂具有良好的生物相容性,易于分离和重复利用,符合绿色化学的发展理念。     

氯化胆碱对MgCl_2·6H_2O脱水及电沉积研究

采用单因素法寻找氯化胆碱对六水氯化镁脱水的最佳试验条件,最终确定了温度、质量比、时间3个主要因素以及各自的4个适宜水平;分别采用正交法、响应曲面法确定了脱水的最优水平组合,并且预测了氯化胆碱对六水氯化镁脱水的最佳实验条件。试验结果表明,最佳脱水条件为:m(MgCl_2·6H_2O):m(氯化胆碱质量)=1:3、160℃、真空干燥22 h。利用脱水后的六水氯化镁混合物在氯化胆碱-尿素离子液体中进行恒电位电解,以铜片为电沉积基体,得到Pr-Mg-Ni合金膜,经EDX分析得合金膜中镁的质量分数达15.03%,所得合金膜表面均匀、致密性好。进一步证明,氯化胆碱对六水氯化镁具有一定的脱水作用,且脱水后产物可直接用于电解制备含镁合金膜。     

利用手持技术改进测定乙醇分子结构实验

利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。     

光谱仪测试范围的扩展

由于石化行业的生产需要，其材质的使用具有多样性和广泛性，经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识，根据光谱仪的测试能力及标样的采集，实现了一个或几个元素测量范围的扩展，并对其测量的影响因素进行了研究。     

Neutral diterpenoids of oleoresins of five species of conifers of Transcarpathia

The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin

The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

物质分配系数的测定实验改进

实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。     

Calculation of enthalpies of hydrogenation of hydrocarbons

Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。