对硝基溴苄提纯时的溶剂选择

对硝基甲苯溴化是常用的合成对硝基溴苄的方法,该法对硝基甲苯是过量的,需选择合适的溶剂用重结晶法除去。由实验结果分析,在常用的几种溶剂中,对硝基甲苯在乙醇中的溶解度随温度升高而增大的趋势最强,且对硝基甲苯和对硝基溴苄在乙醇中的溶解度差异趋势也最明显。     

4，4′-二硝基二苯醚的合成研究

用新的合成路线合成4,4′-二硝基二苯醚。并研究了亚硝酸钠加入方式、母液套用、投料比、反应温度、催化剂用量对反应和产品质量的影响。结论是分批加入亚硝酸钠、母液套用三次、无水碳酸钠过量10％、DMF溶剂下的反应温度为145℃、硝基氯苯摩尔量：CuCl质量为1：1时反应的收率较大、时间较短、动力消耗较少。     

甲烷的特殊性与其命题的研究

甲烷是最简单的烃,是烷烃系列的代表。甲烷在组成、结构及性质等方面有其特殊性,对于解题很有帮助。以下就甲烷的特殊性结合解题进行一下阐述。     

1-（4-硝基苯基）-3-（2-吡啶）三氮烯的合成及其与镉的显色反应

文章研究了新显色剂1-(4-硝基苯基)-3-(2-吡啶)三氮烯NPPDT的合成及其与镉的显色反应的适宜条件.结果表明,在Tween-80的存在下,Ph=9.23的Na2B2O7-NaOH缓冲溶液中,该试剂能与镉发生显色反应,镉与NPPDT形成橙黄色配合物,其最大吸收波长位于464nm处.该方法测定微量镉灵敏度较高,选择性较好.     

Calculation of gas-liquid critical curves for binary systems containing methane

The critical curves for binary systems of methane combined with nitrogen, carbon monoxide, carbon dioxide, ethane, propane, butane and water at temperatures from 125 K to 650 K and pressures from 3.5 MPa to 250 MPa were calculated by using Heilig-Franck equation of state. This equation of state contains a repulsion term and an attraction term for intermolecular interaction. With pairwise combination rules for these potentials, three adjustable parameters are needed. The results showed that the critical curves of the former six binary systems belonged to type I, and CH₄+H₂O system belonged to type III. The calculated data were compared with the experimental data, which yielded good results for the pressure-temperature, pressure-composition and temperature-composition behaviors of the seven systems. Moreover, the values of the adjustable parameters were obtained from the calculation of the critical curves. They can also be used for other relevant calculation.     

甲烷中混有乙烯能用酸性KMnO_4除去吗

KMnO_4和溴水或溴的四氯化碳溶液都是有机化学中常用的试剂,均可用来检验不饱和物质的存在。如检验烷烃中混有的烯烃或炔烃时两者都可以使用。但是如果用其来除去烷烃中混有的不饱和烃效果就不同了。《高中化学实验报告册》(北京师范大学出版     

影响实验室制取甲烷要素探析

甲烷在实验室是采用无水醋酸钠和干燥的碱石灰在加热的情况下进行反应制得,但是在实际的反应过程中有很多细节需要注意,若因为操作不当就会给实验带来副反应较多或是达不到预期的实验效果。     

Molecular simulations of methane, ethane and propane adsorption on TON

The aim of this study was to understand and characterize the adsorption of small alkanes, namely methane, ethane and propane, in zeolite TON through detailed Monte Carlo simulations. The isotherms of pure components were calculated and showed good agreement with experimental data. The adsorption positions, adsorption energy of pure components and isotherms of mixtures were also simulated and the results are discussed.     

最低单态和三态硝基甲烷的分子结构与红外光谱的理论研究

文章运用密度泛函方法B3LYP/6-311++G(2d,2P)研究了最低单态和三态硝基甲烷单分子的电子结构和红外频率,绘制了分子在这两种电子态下的红外振动光谱,对它们的红外振动频率进行了理论归属,分析并比较了两种电子态下分子结构和红外振动情况的变化,结果发现三态的硝基甲烷分子的结构要比基态分子结构稍显松散,稳定性下降,分子振动模式中NO2的相关振动有所加强,红外光谱线左移.因此,最低三态分子沿C-N键分裂而致分子分解的可能性较大.