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Heat Capacities and Thermodynamic Properties of 3-(2,2-Dichloroethenyl)-2,2-dimethylcyclopropanecarboxylic Acid

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Chemical Research in Chinese Universities 2007年第4期23卷 460-464页

作者： XUE Bin WANG Jian-ya tan zhi-cheng WU Tong-hao School of Petrochemical Engineering Shenyang University of Technology Liaoyang 111003 P. R. China College of Chemistry Jilin University Changchun 130021 P. R. China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Science Dalian 116023 P. R. China

The heat capacities of 3-（ 2,2-dichloroethenyl）-2,2-dimethylcyclopropanecarboxylic acid （a racemic mixture, molar ratio of cis-/trans-structure is 35/65） in a temperature range from 78 to 389 K were measured with a precise automatic adiabatic calorimeter. The sample was prepared with a purity of 98.75% （ molar fraction）. A solid-liquid fusion phase transition was observed in the experimental temperature range. The melting point, Tm, enthalpy and en- tropy of fusion, △fusHm, △fusSm, of the acid were determined to be （331.48±0.03 ） K, （16.321±0.031） kJ/mol, and （49.24±0.19） J/（ K·mol）, respectively. The thermodynamic functions of the sample, Ht-H298.15, Sr-S298.15 and Gr-G298.15, were reported at a temperature intervals of 5 K. The thermal decomposition of the sample was studied using thermogravimetric（TG） analytic technique, the thermal decomposition starts at ca. 418 K and ends at ca. 544 K, the maximum decomposition rate was obtained at 510 K. The order of reaction, preexponential factor and activation energy are n =0.23, A =7.3 ×10^7 min^-1 , E =70.64 kJ/mol, respectively.

关键词： 3-(2,2-Dichloroethenyl)-2,2-dimethylcyclopropanecarboxylic acid Adiabatic calorimetry Heat capacity Thermodynamic function Thermal decomposition

Low-temperature Heat Capacities and Thermodynamic Properties of Hydrated Sodium Cupric Arsenate [NaCuAsO_4·1.5H_2O(s)]

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Chemical Research in Chinese Universities 2007年第5期23卷 574-578页

作者： CHEN Jing-tao DI You-ying tan zhi-cheng SUN Li-xian College of Chemistry and Chemical Engineering Liaocheng University Liaocheng 252059 P. R. China Department of Chemistry Shaanxi Educational College Xi＇an 710061 P. R. China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian i 16023 P. R. China

Low-temperature heat capacities of the solid compound NaCuAsO4·1.5H2O（s）were measured using a precision automated adiabatic calorimeter over a temperature range of T=78 K to T=390 K.A dehydration process occurred in the temperature range of T=368-374 *** peak temperature of the dehydration was observed to be TD=（371.828±0.146）K by means of the heat-capacity *** molar enthalpy and entropy of the dehydration were ΔDHm=（18.571±0.142）kJ/mol and ΔDSm=（49.946±0.415）J/（K·mol）,*** experimental values of heat capacities for the solid（Ⅰ）and the solid-liquid mixture（Ⅱ）were respectively fitted to two polynomial equations by the least square *** smoothed values of the molar heat capacities and the fundamental thermodynamic functions of the sample relative to the standard reference temperature 298.15 K were tabulated at an interval of 5 K.

关键词： NaCuAsO4·1.5H2O(s) Adiabatic calorimetry Heat capacity Thermodynamic function Dehydration process

Heat Capacity and Enthalpy of Fusion of Crystalline Pyrimethanil Decylate(C_(22)H_(33)N_3O_2)

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Chemical Research in Chinese Universities 2005年第6期21卷 697-701页

作者： SUN Xiao-hong LIU Yuan-fa tan zhi-cheng WANG Mei-han JIA Ying-qi College of Chemical Engineering Chemical Research Institute Northwest University Xi＇an 710069 P. R. China Department of Chemistry Northwest University Xi＇an 710069 P. R. China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 P. R. China

Low-temperature heat capacities of pyrimethanil decylate （ C22 H33 N3 O2 ） were precisely measured with an automated adiabatic calorimeter over the temperature range from 78 to 373 K. The sample was observed to melt at （311.04 ± 0.06） K. The molar enthalpy and entropy of fusion as well as the chemical purity of the compound were determined to be（45876± 12） J/mol, （147. 50 ±0. 05） J. mol^-1 · K^-1 and （99. 21 ±0. 03）% （mass fraction）, respectively. The extrapolated melting temperature for the absolutely pure compound obtained from fractional melting experiments is （311. 204±0. 035 ） K.

关键词： Pyrimethanil decylate Heat capacity Adiabatic calorimetry DSC

Heat Capacity and Thermodynamic Properties of Crystalline 2-Chloro- N, N-dimethylnicotinamide

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Chinese Journal of Chemistry 2005年第11期23卷 1490-1494页

作者： SUN, Xiao-Hong LIU, Yuan-Fa tan, zhi-cheng JI, Peng-Ju WANG, Mei-Han College of Chemical Engineering Chemical Research Institute Northwest University Xi'an Shaanxi 710069 China Department of Chemistry Northwest University Xi'an Shaanxi 710069 China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian Liaoning 116023 China

Low-temperature heat capacities of 2-chloro-N,N-dimethylnicotinamide were precisely measured with a high-precision automated adiabatic calorimeter over the temperature range from 82 K to 380 K. The compound was observed to melt at （342.15±0.04） K. The molar enthalpy AfusionHm, and entropy of fusion, △fusionSm, as well as the chemical purity of the compound were determined to be （21387±7） J·mol^-1, （62.51±0.01） J·mol^-1·K^-1, （0.9946±0.0005） mass fraction, respectively. The extrapolated melting temperature for the pure compound obtained from fractional melting experiments was （342.25±0.024） K. The thermodynamic function data relative to the reference temperature 298.15 K were calculated based on the heat capacity measurements in the temperature range from 82 to 325 K. The thermal behavior of the compound was also investigated by different scanning calorimetry.

关键词： 2-chloro-N,N-dimethylnicotinamide heat capacity adiabatic calorimetry

Low Temperature Heat Capacities and Thermodynamic Properties of Zinc L-Threonate Zn(C_4H_7O_5)_2(s) by Adiabatic Calorimetry

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Chemical Research in Chinese Universities 2008年第5期24卷 603-607页

作者： CHEN Jing-tao DI You-ying tan zhi-cheng CHEN San-ping GAO Sheng-li Department of Chemistry Shaanxi Educational College Xi＇an 710061 P. R. China College of Chemistry and Chemical Engineering Liaocheng University Liaocheng 252059 P. R. China Department of Chemistry Northwest University Xi＇an 710069 P. R. China

Low-temperature heat capacities of the solid compound Zn（C4H7O5）2（s） were measured in a temperature range from 78 to 374 K, with an automated adiabatic calorimeter. A solid-to-solid phase transition occurred in the temperature range of 295？322 K. The peak temperature, the enthalpy, and entropy of the phase transition were determined to be （316.269±1.039） K, （11.194±0.335） kJ？mol-1, and （35.391±0.654） J？K-1？mol-1, respectively. The experimental values of the molar heat capacities in the temperature regions of 78？295 K and 322？374 K were fitted to two polynomial equations of heat capacities（Cp,m） with reduced temperatures（X） and [X = f（T）], with the help of the least squares method, respectively. The smoothed molar heat capacities and thermodynamic functions of the compound, relative to that of the standard reference temperature 293.15 K, were calculated on the basis of the fitted polynomials and tabulated with an interval of 5 K. In addition, the possible mechanism of thermal decomposition of the compound was inferred by the result of TG-DTG analysis.

关键词： Zn(C4H7O5)2(s) Adiabatic calorimetry Low-temperature heat capacity Solid-to-solid phase transition Thermodynamic property TG-DTG

Low-temperature Heat Capacities and Thermodynamic Properties of Solid State Coordination Compound Zn(nicotinate)_2·H_2O(s)

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Chemical Research in Chinese Universities 2009年第4期25卷 526-531页

作者： CHEN Jing-tao DI You-ying DAN Wen-yan HONG Yuan-ping YANG Wei-wei KONG Yu-xia HE Dong-hua tan zhi-cheng College of Chemistry and Chemical Engineering Liaocheng University Liaocheng 252059 P. R. China Department of Chemistry Shaanxi Educational College Xi ＇an 710061 P. R. China

A novel compound-monohydrated zinc nicotinate was prepared via room temperature solid phase synthesis and ball ***,chemical and elemental analyses and X-ray powder diffraction technique were applied to characterizing the structure and composition of the ***-temperature heat capacities of the solid coordination compound were measured by a precision automated adiabatic calorimeter over a temperature range from 77 to 400 K.A solid-solid phase transition process occurred in a temperature range of 321―342 K inferred according to the heat capacity curve,and the peak temperature,molar enthalpy and entropy of the phase transition of monohydrated zinc nicotinate were determined to be Ttrs=（340.584±0.829） K,ΔtrsHm=（12.682±0.041） kJ/mol and ΔtrsSm=（37.235±0.101） KJ/mol）.The experimental values of the molar heat capacities in the temperature regions of 77―321 K and 342―400 K were,respectively,fitted to two polynomial *** addition,the polynomial fitted values of the molar heat capacities and fundamental thermodynamic functions of the sample relative to the standard reference temperature 298.15 K were calculated and tabulated at intervals of 5 K.

关键词： Zinc nicotinate Adiabatic calorimeter Heat capacity Phase transition Thermodynamic function

基于数值模拟的新型合流制溢流调蓄池优化研究

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中国给水排水 2021年第23期37卷 114-121页

作者：谭志程余健湖南大学土木工程学院湖南长沙410082

针对合流制溢流污染现状,构建了一种有效容积为5000 m^(3)的新型合流制溢流调蓄池,并利用计算流体力学软件FLUENT对新型调蓄池进行三维的固-液两相流数值模拟,采用稳态模拟与正交试验相结合的方法优化其内部结构并分析池内物理量场的分... 详细信息

针对合流制溢流污染现状,构建了一种有效容积为5000 m^(3)的新型合流制溢流调蓄池,并利用计算流体力学软件FLUENT对新型调蓄池进行三维的固-液两相流数值模拟,采用稳态模拟与正交试验相结合的方法优化其内部结构并分析池内物理量场的分布;采用非稳态模拟的方法讨论其对场次降雨所产生的溢流污染的去除效果。模拟结果表明,稳态条件下,当水力停留时间为0.7 h时,池体的最佳结构尺寸如下:进水口长度为1.6 m、竖直挡板深度为2 m、水平挡板长度为0.75 m、底部斜板角度为45°,折流段对SS的去除率为97.3%;非稳态条件下,新型调蓄池对重现期≤1年的场次降雨产生的超量溢流污染的去除率为同等体积传统调蓄池的2倍左右。

关键词：合流制溢流污染新型调蓄池计算流体力学非稳态模拟

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正二十二烷醇的热力学性质

物理化学学报 2008年第9期24卷 1699-1702页

作者：童波谭志诚王韶旭中国科学院大连化学物理研究所热化学实验室辽宁大连116023 大连交通大学环境与化学工程学院辽宁大连116028

用精密自动绝热量热仪测定了广谱抗病毒药物正二十二烷醇在78-400K温区的热容.根据实验测定的热容数据,用最小二乘法拟合计算出热容对温度的多项式方程,得到其相变温度、相变焓、相变熵分别为340.844K、85.07kJ·mol-1、249.6J·K-1·mo... 详细信息

用精密自动绝热量热仪测定了广谱抗病毒药物正二十二烷醇在78-400K温区的热容.根据实验测定的热容数据,用最小二乘法拟合计算出热容对温度的多项式方程,得到其相变温度、相变焓、相变熵分别为340.844K、85.07kJ·mol-1、249.6J·K-1·mol-1.根据热力学函数关系式计算了其在80-400K温区每隔5K的热力学函数[HT-H298.15]和[ST-S298.15].用DSC、TG热分析技术进一步考查了该物质在400-900K的热稳定性.

关键词：正二十二烷醇热容 DSC TG 热力学性质

配合物Zn(Phe)(NO_3)_2·H_2O(s)的低温热容和标准摩尔生成焓

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物理化学学报 2007年第9期23卷 1437-1441页

作者：邸友莹高胜利谭志诚聊城大学化学化工学院山东聊城252059 西北大学化学系西安710069 中国科学院大连化学物理研究所热化学实验室辽宁大连116023

利用精密自动绝热热量计直接测定了配合物Zn(Phe)(NO_3)_2·H_2O(s)(Phe:苯丙氨酸)在78-370 K温区的摩尔热容.通过热容曲线的解析得到该配合物的起始脱水温度为,T_0=(324.27±0.37)K.将该温区的摩尔热容实验值用最小二乘法拟合得到摩尔... 详细信息

利用精密自动绝热热量计直接测定了配合物Zn(Phe)(NO_3)_2·H_2O(s)(Phe:苯丙氨酸)在78-370 K温区的摩尔热容.通过热容曲线的解析得到该配合物的起始脱水温度为,T_0=(324.27±0.37)K.将该温区的摩尔热容实验值用最小二乘法拟合得到摩尔热容(C_(p,m))对温度(T)的多项式方程,并且在此基础上计算出了它的舒平热容值和各种热力学函数值.依据Hess定律,通过设计热化学循环,选择体积为100 mL浓度为2 mol·L^(-1)的盐酸作为量热溶剂,利用等温环境溶解-反应热量计分别测定混合物{ZnSO_4·7H_2O(s)+2NaNO_3(s)+L-Phe(s)}和{Zn(Phe)(NO_3)_2·H_2O(s)+Na_2SO_4(s)}的溶解焓为,Δ_dH_(m,1)~0=(69.42±0.05)kJ·mol^(-1),Δ_dH_(m,2)~0=(48.14±0.04)kJ·mol^(-1),进而计算出该配合物的标准摩尔生成焓为,Δ_fH_m^0=-(1363.10±3.52)kJ·mol^(-1).另外,利用紫外-可见(UV-Vis)光谱和折光指数(refractive index)的测量结果检验了所设计的热化学循环的可靠性.

关键词： Zn(Phe)(NO3)2·H2O(s) 绝热量热法低温热容溶解-反应量热法标准摩尔生成焓