Liquid viscosities and densities of HFC-134a+glycol mixtures

Liquid viscosity and density of six binary mixtures of HFC-134a with glycols [ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (400), and polypropylene glycol (2000)] have been measured in the temperature range from 273 to 333 K. The viscosity was measured by a rolling-ball viscometer calibrated with standard liquids of viscosities and densities (JS5, JS10, JS20, and JS50). The density was measured with a glass pycnometer. The uncertainties of the measurements were estimated to be less than 3.4 % for viscosity and 0.04 % for density, respectively. An equation is given to represent the obtained viscosity values as a function of weight fraction and temperature.     

烃类在三甘醇和四甘醇中无限稀释活度系数的测定与关联

用气相色谱法分别测定了苯、甲苯、乙苯、正庚烷、正辛烷、正壬烷和正癸烷在三甘醇和四甘醇中的无限稀释活度系数 ,测定温度范围为 5 0～ 13 0℃。用修正的UNIFAC模型 (Dortmund)对上述不同温度下的无限稀释活度系数实验数据进行关联 ,得到了三甘醇和四甘醇与其它基团的相互作用参数 ,并将计算结果与实测值进行了比较。     

花片状钌纳米颗粒的控制合成

以三氯化钌为前驱体、聚乙烯吡咯烷酮（PVP）为稳定荆、三缩四乙二醇（TEG）和Zn粉为还原剂,于170℃反应2h。再加入适量十六烷基三甲基溴化铵（CTAB）,继续反应4h成功制得花片状Ru纳米颗粒。反应体系中最适宜RuCl2：PVP：CTAB：Zn（摩尔比）为1：20：1：1．5。产物用透射电子显微镜（TEM）、X-射线粉末衍射（XRD）、紫外可见吸收光谱（UV—Vis）等进行了表征。     

甲苯-正庚烷-(环丁砜+四甘醇)体系液-液平衡数据的测定与关联

利用气相色谱法测定了常压下30,40,50℃时甲苯-正庚烷-(环丁砜+四甘醇)体系的液-液平衡数据,采用峰面积相对质量校正因子归一化法定量。用NRTL模型对所测数据进行了热力学关联,关联时采用封闭体系的热力学平衡准则-混合吉布斯自由能最小来解决其多值问题。用单纯形优化法,选用摩尔分数目标函数求出了相应的模型参数。用该模型对本体系进行了计算,计算值与实测值的平均偏差较小,结果令人满意。     

Viscosity of the binary systems containing trifluoroethanol,water and tetraethylene glycol dimethyl ether. Prediction of the ternary viscosity from binary data

Kinematic viscosities were measured over the entire range of composition and at atmospheric pressure for the binary systems trifluoroethanol (TFE)-H₂O, TFE-tetraethylene glycol dimethyl ether (TEGDME), and TEGDME-H₂O from 293.15 to 333.15 K. The data were fitted by the Stephan and Heckenbergber (1989) correlation, which accounts for the dependence on temperature and mixture composition. Methods for predicting ternary excess viscosities from excess viscosity data for the three binary mixtures involved are examined and tested for the system TFE-H₂O-TEGDME at 303.15 K by comparing predicted and experimental data. The empirical correlation of Colinet (1967) is shown to be the best for this system.     

微波辐照下铂纳米颗粒的形貌控制合成

以氯铂酸为前体、聚乙烯吡咯烷酮和十六烷基三甲基溴化铵为保护剂、乙二醇和三缩四乙二醇混合物为溶剂及还原剂,在一定量KOH存在下,微波辐照加热100 s,制备"爆米花"形铂纳米颗粒.通过调节乙二醇和三缩四乙二醇的体积比可以控制"爆米花"形铂纳米颗粒的大小.     

Densities,viscosities, and excess properties of trifluoroethanol-water,tetraethylene glycol dimethylether-water,and trifluoroethanol-tetraethylene glycol dimethylether at 303.15 K

Densities and kinematic viscosities of trifluoroethanol + water, tetraethylene glycol dimethylether + water, and trifluoroethanol + tetraethylene glycol dimethylether have been measured at 303.15 K and atmospheric pressure over the entire range of composition. Dynamic viscosities, excess volumes, excess viscosities, and excess Gibbs energies of activation of flow were obtained from the experimental results. The excess volumes were negative, whereas excess viscosities and energies of activation were positive, presenting the three thermodynamic properties asymmetric composition dependence. The kinematic viscosities were used to test McAllister, Stephan, and Soliman and Marshall correlations.     

液相法甲醇合成的平衡收率

对液相法甲醇合成系统进行了热力学分析，建立了求解该系统相平衡和化学平衡问题的非线性方程组。在此基础上，分别对以四甘醇二甲醚和角鲨烷为液相介质的反应热力学平衡进行了计算，结果表明液相介质具有提高甲醇平衡收率的作用。研究了液相介质的性能、用量、温度、压力及原料气组成对甲醇平衡收率的影响。     

离子交换法再生处理四甘醇溶剂的工艺研究

用于石化厂中间产品提纯工艺中的四甘醇溶剂，因积累有机色素而需要再生处理。选用的大孔阴离子交换树脂可以吸附溶剂中的有机色素达80％左右。对负载有机色素的树脂可用1mol／LHCl溶液淋洗，经水洗后用1mol／LNaOH溶液转型，再经水洗后返回吸附。在充分返回利用部分酸、碱溶液的条件下，酸、碱用量不大。该处理工艺具有实用价值。     

溶剂稳定的钯金属纳米颗粒的制备与催化性能

用三缩四乙二醇作溶剂,制备了溶剂稳定的钯金属纳米颗粒,得到了分布均匀、粒径在2～3nm范国内的钯金属纳米颗粒。所得到的钯金属纳米颗粒用于环已烯的催化加氢反应,其催化活性较传统的钯／碳催化剂约高2倍。