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AN AUTOMATED ADIABATIC CALORIMETER FOR USE FROM 80 TO 600 K——HEAT CAPACITIES OF α-ALUMINA

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中国科学B辑(英文版) 1986年第12期29卷 1239-1247页

作者：张志英 thermochemistry laboratory Northwestern University Xi’an

The construction of an automated adiabatic calorimeter for use from 80 to 600 K is reported. The main feature of the calorimoter is to mount three radiation shields in the cryostat for advancing the working tomperature. The molar heat capacity of α-Al2O3 has been measured in order to assess the reliability of the calorimeter. Deviations of the experimental heat capacities of α-Al2O3 from the smoothed curve are within ±0.3% except for a few experimental points. Our smoothed results agree with those of tho National Bureau of Standards. USA, within ±0.3% over the entire working temperature range.

关键词： smoothed advancing calorimeter automated mount ALUMINA satis molar timer illustrated

Estimation of the lattice heat capacity of rare-earth compounds

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Chinese Journal of Chemistry 1986年第1期4卷 7-19页

作者： ZHANG Zhi-Ying thermochemistry laboratory, Northwestern University, Xi’an thermochemistry laboratory Northwestern University Xi'an

On the basis of the experimental data reported in literature, the contributions of cationmass （m） and molar volume （V） to lattice heat capacity （C） were analyzed. The volumetric-mass formula,C=（1-f）·C+f·C+Cm·（m-m’）, was presented for estimating the heat capacities of rare-earthcompounds. In the formula Cand Crepresent the lattice heat capacities of two reference sub-stances respectively, f=V-V/V-Vand Cm represents the lattice heat capacity variation withthe variation 1 g of cation mass. The equation relating the Cm with temperatures was derived as fol-lows: Cm=0.084 e-0.27 e, and mand m’ (=（1-f） m+f m) represent thepractical and "assumed" cation masses of the substance in question respectively.

关键词： heat Estimation of the lattice heat capacity of rare-earth compounds

Estimation of the lattice entropy of rare-earth compounds

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Chinese Journal of Chemistry 1984年第2期2卷 89-94页

作者： ZHANG Zhi-Ying thermochemistry laboratory,Northwestern University,Xi’an thermochemistry laboratory Northwestern University Xi'an

Resolution of excess entropy of many types of transitions and estimation of standardentropy at 298.15K of compounds,for which experimental entropies have not yet been measured,depend on a reliable estimation of the lattice *** taking into account the effects of cationmass and molar volume of the rare-earth compounds,the following formula is proposedS~(0298.15)=S~(0ref)+3/2n1′·R·InM/(Mref)+3/2n2·R·InV/(Vref)for the estimation of the lattice entropy of isostructural iso-anionic rare-earth *** investigated 32 compounds,and found good agreements between estimated and experimentalentropies.

关键词： Estimation of the lattice entropy of rare-earth compounds

Low-Temperature Heat Capacity and Thermal Decomposition of Crystalline[Ho(Thr)(H_2O)_5]Cl_3

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Chinese Journal of Chemistry 2003年第8期21卷 1043-1046页

作者：蓝孝征谭志诚刘北平南照东孙立贤徐芬 thermochemistry laboratory Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian

Rare earth elements have been widely used in many areas. Rare earth complex bearing an amino acid was synthesized to study the influence and the long term effect of rare earth elements on environment and human beings, because amino acid is the basic unit of the living things. Previous work on these kinds of complex is focused on synthesis and characterization of them. But their thermodynamic data have seldom been reported. Here we present the thermodynamic study of [Ho(H 2O) 5]Cl 3. The heat capacity of Holmium complex with threonine, [Ho(Thr)(H 2O) 5]Cl 3 , was measured with an automatic adiabatic calorimeter in the temperature range from 79 K to 330 K and no thermal anomaly was found in this range. Thermodynamic functions relative to standard state 298 15 K were derived from the heat capacity data. Thermal decomposition behavior of the complex in nitrogen atmosphere in the range from 300 K to 900 K was studied by thermogravimetric (TG) technique and a possible decomposition mechanism was proposed according to the TG DTG results.

关键词： RE complex of threonine heat capacity thermal decomposition adiabatic calorimetry thermodynamic function TG analysis

Low-temperature heat capacities and standard molar enthalpy of formation of pyridine-2,6-dicarboxylic acid

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Chinese Physics B 2010年第6期19卷 188-194页

作者：杨伟伟邸友莹孔玉霞谭志诚 College of Chemistry and Chemical Engineering Liaocheng University thermochemistry laboratory Dalian Institute of Chemical PhysicsChinese Academy of Sciences

This paper reports that the low-temperature heat capacities of pyridine-2,6-dicarboxylic acid were measured by a precision automatic calorimeter over a temperature range from 78 K to 380 K. A polynomial equation of heat capacities as a function of temperature was fitted by the least-squares method. Based on the fitted polynomial, the smoothed heat capacities and thermodynamic functions of the compound relative to the standard reference temperature 298.15 K were calculated and tabulated at intervals of 5 K. The constant-volume energy of combustion of the compound was determined by means of a precision rotating-bomb combustion calorimeter. The standard molar enthalpy of combustion of the compound was derived from the constant-volume energy of combustion. The standard molar enthalpy of formation of the compound was calculated from a combination of the datum of the standard molar enthalpy of combustion of the compound with other auxiliary thermodynamic quantities through a Hess thermochemical cycle.

关键词： pyridine-2,6-dicarboxylic acid adiabatic calorimetry low-temperature heat capacity standard molar enthalpy of formation

Microencapsulation of n-Eicosane as Energy Storage Material

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Chinese Journal of Chemistry 2004年第5期22卷 411-414页

作者：蓝孝征谭志诚邹光龙孙立贤张涛 thermochemistry laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian Liaoning 116023 China

For heat energy storage application, polyurea microcapsules containing phase change material, n-eicosane, were synthesized by using interfacial polymerization method with toluene-2,4-diisocyanate (TDI) and diethylenetriamine (DETA) as monomers in an emulsion system. Poly(ethylene glycol)octyl-phenyl ether (OP), a nonionic surfactant, was the emulsifier for the system. The experimental result indicates that TDI was reacted with DETA in a mass ratio of 3 to 1. FT-IR spectra confirm the formation of wall material, polyurea, from the two monomers, TDI and DETA. Encapsulation efficiency of n-eicosane is about 75%. Microcapsule of n-eicosane melts at a temperature close to that of n-eicosane, while its stored heat energy varies with core material n-eicosane when wall material fixed. Thermo-gravimetric analysis shows that core material n-eicosane, micro-n-eicosane and wall material polyurea can withstand temperatures up to 130, 170 and 250 ℃, respectively.

关键词： phase change material n-eicosane microcapsule interfacial polymerization heat energy storage thermal analysis

A small sample-size automated adiabatic calorimeter from 70 to 580 K——Molar heat capacities of α-Al_2O_3

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Science China Chemistry 1999年第4期42卷 382-390页

作者：谭志诚张际标孟霜鹤李莉 1. thermochemistry laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences 116023 Dalian China

An automatic adiabatic calorimeter for measuring heat capacities in the temperature range 70-580K, equipped with a small sample cell of 7.4 cm3 in the internal volume has been developed. In order to obtain a good adiabatic condition of the calorimeter at high temperature, the calorimeter was surrounded in sequence by two adiabatic shields, three radiation shields and an auxiliary temperature-controlled sheath. The main body of the cell made of copper and the lid made of brass are silver-soldered and the cell is sealed with a copper screw cap. A sealing gasket made of Pb- Sn alloy is put between the cap and the lid to ensure a high vacuum sealing of the cell in the whole experimental temperature range. All the leads are insulated and fixed with W30-11 varnish, thus a good electric insulation is obtained at high temperature. All the experimental data, including those for energy and temperature are collected and processed automatically with a personal computer using a predetermined program. To verify the accuracy of the calorimeter, the heat capacities of α-Al2O3 of the calorimetric standard reference material is measured. The standard deviations of experimental heat capacity values from the smoothed values are within ±0.28%, while the inaccuracy is within ±0.4% compared with those of the National Bureau of Standards over the entire working temperature range.

关键词： adiabatic calorimetry calorimetric technique heat capacity α-Al2o3 small sample.

Unleashing the Power of Bio-based Thermotropic Liquid Crystal Modifiers:Toughening and Reinforcing Petroleum-based Epoxy Resin without Compromising Other Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1093-1102页

作者： Qing-Yun Lu Hong-Wei Gu Jia-Hui Li Qian-Qian Fan Bei-Tao Liu Yan Kou Xi-Gao Jian Zhi-Huan Weng State Key laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsLiaoning Technology Innovation Center of High Performance Resin MaterialsDepartment of Polymer Science&EngineeringDalian University of TechnologyDalian 116024China thermochemistry laboratory Liaoning Province Key Laboratory of Thermochemistry for Energy and MaterialsDalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Toughening the petroleum-based epoxy resin blends with bio-based modifiers without compromising their modulus,mechanical strength,and other properties is still a big challenge in view of the *** this study,a bio-based liquid crystal epoxy resin(THMT-E P)with an s-triazine ring structure was utilized to modify a petroleum-based bisphenol A epoxy resin(E51)with 4,4'-diaminodiphenylsulfone(DDS)as a curing agent,and the blended systems were evaluated for their thermal stability,mechanical properties,and flame *** results showed that the impact strength of the blended system initially increased and then decreased with the increase in THMT-EP content,and it reached the a maximum value of 26.5 kJ/m^(2)when the THMT-EP content was 5%,which was 31.2%higher than that of E51/***,the flexural strength,modulus,and glass transition tem perature of the blended system were all simultaneously improved with the addition of *** the same time,the addition of THMT-EP enhanced the flame retardancy of the system by increasing the char yield at 700℃and decreasing the peak heat release rate and total heat release *** work paves the way for a more sustainable improvement in the comprehensive performance of epoxy resin.

关键词： Epoxy resin Toughening Bio-based Thermotropic liquid crystal

Thermodynamic Investigation of the Azeotropic Mixture Composed of Water and Benzene

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Chinese Journal of Chemistry 2004年第1期22卷 4-8页

作者：南照东谭志诚 Department of Chemistry Liaoning Normal University thermochemistry laboratory Dalian Institute of Chemical PhysicsChinese Academy of Sciences

The molar heat capacity of the azeotropic mixture composed of water and benzene was measured by an adia-batic calorimeter in the temperature range from 80 to 320 K. The phase transitions took place in the temperature range from 265.409 to 275.165 K and 275.165 to 279.399 K. The phase transition temperatures were determined to be 272.945 and 278.339 K, which were corresponding to the solid-liquid phase transitions of water and benzene, respectively. The thermodynamic functions and the excess thermodynamic functions of the mixture relative to stan-dard temperature 298.15 K were derived from the relationships of the thermodynamic functions and the function of the measured heat capacity with respect to temperature.

关键词： azeotropic mixture water benzene heat capacity adiabatic calorimetry