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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 Enthalpy of Fusion of Fenoxycarb

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Chinese Journal of Chemistry 2005年第5期23卷 501-505页

作者：孙晓红刘源发谭志诚贾婴琦杨建武王美涵 CollegeofChemicalEngineering ChemicalResearchInstituteNorthwestUniversityXi'anShaanxi710069China//DepartmentofChemistryNorthwestUniversityXi'anShaanxi710069China DepartmentofChemistry NorthwestUniversityXi'anShaanxi710069China ThermochemistryLaboratory DalianInstituteofChemicalPhysicsChineseAcademyofSciencesDalianLiaoning116023China CollegeofChemicalEngineering ChemicalResearchInstituteNorthwestUniversityXi'anShaanxi710069China

Fenoxycarb was synthesized and its heat capacities were precisely measured with an automated adiabatic calorimeter over the temperature range from 79 to 360 K. The sample was observed to melt at (326.31±0.14) K. The molar enthalpy and entropy of fusion as well as the chemical purity of the compound were determined to be (26.98±0.04) kJ·mol ‐1 , (82.69±0.09) J·K ‐1 ·mol ‐1 and 99.53%±0.01%, respectively. The thermodynamic functions relative to the reference temperature (298.15 K) were calculated based on the heat capacity measurements in the temperature range between 80 and 360 K. The extrapolated melting temperature for the absolutely pure compound obtained from fractional melting experiments was (326.62±0.06) K. Further research on the melting process of this compound was carried out by means of differential scanning calorimetry technique. The result was in agreement with that obtained from the measurements of heat capacities.

关键词： fenoxycarb heat capacity thermodynamic functions adiabatic calorimetry differential scanning calorimetry

heat capacity and Thermodynamic Properties of Myclobutanil

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Chinese Journal of Chemistry 2005年第1期23卷 23-27页

作者：孙晓红刘源发谭志诚贾婴琦王美涵邸友莹 DepartmentofChemistry NorthwestUniversityXi'anShaanxi710069China ChemicalEngineeringCollege ChemicalResearchInstituteNorthwestUniversityXi'anShaanxi710069China ThermochemistryLaboratory DalianInstituteofChemicalPhysicsChineseAcademyofSciencesDalianLiaoning116023China

The low‐temperature heat capacities of myclobutanil (C 15 H 17 ClN 4 ) were precisely measured with an automated adiabatic calorimeter over the temperature range from 78 to 368 K. The sample was observed to melt at (348.800 ±0.06) K. The molar enthalpy and entropy of the melting as well as the chemical purity of the substance were determined to be Δ fus H m (30931±11) J · mol −1 , Δ fus S m (88.47±0.02) J · mol −1 · K −1 and 99.41%, respectively. Further research of the melting process for this compound was carried out by means of DSC technique. The result was in agreement with that obtained from the measurements of heat capacities.

关键词： myclobutanil heat capacity adiabatic calorimetry DSC

heat capacity of Sodium Ditungstate Na_2W_2O_7(s)

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Chinese Chemical Letters 1998年第5期9卷 495-496页

作者： Shi Jun LIU Qi Yuan CHEN Ping Min ZHANG(Department of Chemistry, Central South University of Technology, Changsha 4l0083) Department of Chemistry Ctrl. South University of Technology Changsha 410083 China

The heat capacity of Na2W2O7(s) has been measured using the dropcalorimetry method with a high temperature calorimeter HT1000 in the temperaturerange of 273-974K. The resultS can be represented by the equation C,o/J K... 详细信息

关键词： heat capacity sodium ditungstate,calorimetry

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 capacity of Zn Substituted Cobalt Ferrite Nanosphere:The Relation between Magnetic Properties and Microstructure

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 984-995页

作者： YUAN Meng GU Xiaojie FU Jie WANG Shaoxu SHI Quan TAN Zhicheng XU Fen College of Environmental and Chemical Engineering Dalian Jiaotong UniversityDalian I16028China Thermochemistry Laboratory Dalian Institute of Chemical PhysicsChinese Academy of ScienceDalian Il6023China Guangxi Key Laboratory of Information Materials(Guilin University of Electronic Technology) Guilin 541000China

Co_((1-x))ZnxFe_(2)O_(4)nanospheres(x=0,0.5,0.8)with a unidirectional cubic spinel structure were prepared by a solvothermal *** using a range of theoretical and empirical models,the experimental heat capacity values were fitted as a function of temperature over a suitable temperature range to explain the possible relationship between the magnetic properties and microstructure of the *** a result,at a low temperature(T50 K),the Debye temperature decreases with increasing Zn concentration,which is due to the weakening of the interatomic bonding force after the addition of non-magnetic materials to the Co Fe_(2)O_(4)spinel ferrite.

关键词： Co-Zn spinal ferrite nanospheres magnetic properties heat capacity thermodynamic functions PPMS

Thermodynamic properties and heat capacity of Ru metal in HCP,FCC,BCC and liquid state

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Transactions of Nonferrous Metals Society of China 2010年第10期20卷 1950-1956页

作者：彭红建周姣连谢佑卿 School of Chemistry and Chemical Engineering Central South University School of Materials Science and Engineering Central South University

Isometric heat capacity cv and isobar heat capacity cp of Ru metal in HCP,FCC,BCC and liquid state were calculated by using pure element systematic *** results are in good agreement with joint army-navy-air force(JANAF) experimental value and the calculation result by first-principle(FP) *** the results have great differences in contrast to Scientific Group Thermodata Europe(SGTE) *** cause is found that it cannot neglect the electron devotion to heat capacity to adjust cp in one-atom(OA) *** disparity between OA method and SGTE database was *** main cause is that OA method adopts the crosspoint with iso-Ec-line and iso-a-line in hybritriangle to determine the properties,but SGTE database is obtained by extrapolation from activity measurements and critical assessment of data from a large number of binary *** properties of Ru metal in HCP,FCC,BCC and liquid state,such as entropy S,enthalpy H and Gibbs energy G were ***,the full description of thermodynamic properties from 0 K to random temperature is implemented.

关键词： Ru metal heat capacity thermodynamic property OA method

Zero-Thermal Expansion and heat capacity of Zirconium Pyrovanadate Doped with Zirconia and Vanadium (V) Oxide

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Rare Metals 2001年第1期20卷 1-4页

作者： Xianran Xing, Zhenqi Zhu, Xinping Qiu, Guirong Liu (Dept. of Physical Chemistry University of Science and Technology Beijing, Beijing 100083, China Dept. of Chemistry, Tsinghua University, Beijing 100084, China) 北京科技大学北京 100083 清华大学北京 100084)

The dominant phase ZrV2O7 material, doped with zirconia and vanadium (V) oxide, was synthesized by solid state reaction and sol-gel methods. X-ray power diffraction patterns show that it is cubic structure. Thermal mechanic analysis measurements exhibit a zero-thermal expansion of this material above 150 degreesC. Meanwhile, the heat capacity dependent on temperature, determined by differential scanning calorimetry, keeps in constant almost in the same temperature range. The relationship between unusual thermal expansion and abnormal heat capacity is discussed with Gruneisen parameter.

关键词： zero-thermal expansion of ZrV2O7 heat capacity Gruneisen parameter

Structure and heat capacity of the NaCeF_4 compound

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Journal of Rare Earths 2013年第9期31卷 911-915页

作者： Virgil Constantin Ana-Maria Popescu "Ilie Murgulescu" Institute of Physical Chemistry of the Romanian Academy Splaiul Independentei 202 st.060021BucharestRomania

This work continued our general research program on obtaining metallic cerium by electrodeposition from NaCeF4 dis-solved in different molten fluorides. The structure of NaCeF4 （cubic or hexagonal depending on the way of preparation） was estab-lished by DTA analysis, IR spectra and X-ray diffraction. The heat capacity （Cp） of NaCeF4 was measured by differential scanning calorimetry in the temperature range of 300-1093 K using the“step-method”. The Cp was fitted by an equation with a satisfactory re-sult. heat capacity was compared with that calculated from the Neumann-Kopp rule （NKR） and the deviations observed were consis-tent with the stability of the NaCeF4 compound.

关键词： cerium compounds structure heat capacity NaCeF4 rare earths