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Adiabatic Calorimeter (adiabatic + calorimeter)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Novel Synthesis of , -FeOOH Nanofluid and Determination of Its Heat Capacity by an Adiabatic Calorimeter

CHINESE JOURNAL OF CHEMISTRY, Issue 7 2009
Zhaodong NAN
Abstract A novel and facile method for preparation of stable nanofluid is introduced, in which FeCl3·6H2O and urea were used as reactants without any surfactants. The obtained solid sample was proved to be , -FeOOH by XRD technology and spindle-shaped by TEM technology. The coexisting NH3 molecules may be the main reason for the stable nanofluid. The weak bonding between nitrogen and iron atoms would be formed. The investigation on the excess heat capacity of the obtained nanofluid sustains this opinion. The heat capacities of the obtained , -FeOOH particles and the nanofluid were determined by an adiabatic calorimeter. And these obtained results will help the applications of , -FeOOH and the nanofluid to industry, and the establishment of the model of thermal conductivity of nanofluid. The thermodynamic properties of the obtained , -FeOOH particles and the nanofluid were calculated based on the obtained functions of heat capacity with respective to thermodynamic temperature and the relationships between the thermodynamic properties. [source]

Measurements of the Heat Capacity of an Azeotropic Mixture of Water and n -Butanol from 78 to 320 K

CHINESE JOURNAL OF CHEMISTRY, Issue 10 2005
Zhao-Dong Nan
Abstract Molar heat capacities of n -butanol and the azeotropic mixture in the binary system [water (x=0.716) plus n -butanol (x=0.284)] were measured with an adiabatic calorimeter in a temperature range from 78 to 320 K. The functions of the heat capacity with respect to thermodynamic temperature were established for the azeotropic mixture. A glass transition was observed at (111.9±1.2) K. The phase transitions took place at (179.26±0.77) and (269.69±0.14) K corresponding to the solid-liquid phase transitions of n -butanol and water, respectively. The phase-transition enthalpy and entropy of water were calculated. A thermodynamic function of excess molar heat capacity with respect to temperature was established, which took account of physical mixing, destructions of self-association and cross-association for n -butanol and water, respectively. The thermodynamic functions and the excess thermodynamic ones of the binary systems relative to 298.15 K were derived based on the relationships of the thermodynamic functions and the function of the measured heat capacity and the calculated excess heat capacity with respect to temperature. [source]

Thermodynamic Investigation of the Azeotropic Mixture Composed of Water and Benzene

CHINESE JOURNAL OF CHEMISTRY, Issue 1 2004
Zhao-Dong Nan
Abstract The molar heat capacity of the azeotropic mixture composed of water and benzene was measured by an adiabatic 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 standard 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. [source]

Hazard ratings for organic peroxides

PROCESS SAFETY PROGRESS, Issue 2 2008
Yih-Shing Duh
Abstract Nine of commercially available organic peroxides were assessed with differential scanning calorimeter (DSC) and adiabatic calorimeters. These organic peroxides are cumene hydroperoxide (CHP), di- tert -butyl peroxide (DTBP), methyl-ethyl-ketone peroxide (MEKPO), tert -butyl hydroperoxide (TBHP), benzoyl peroxide (BPO), hydrogen peroxide, lauroyl peroxide (LPO), tert -butyl peroxybenzoate (TBPBZ), and dicumyl peroxide (DCPO). Exothermic onset temperatures, self-heat temperature and pressure rates, and heats of decomposition were measured and assessed. Adiabatic runaway reaction characteristics were determined by using ARC (accelerating rate calorimeter) and VSP2 (vent sizing package). Incompatibility, tests with several potential contaminants, was made using DSC, VSP2, and microcalorimeter. An incompatibility rating was developed using onset temperature, lowering of the onset temperature, heat of decomposition, maximum self-heat rate, adiabatic temperature rise, maximum pressure of decomposition, and maximum pressure rising rate, etc. © 2008 American Institute of Chemical Engineers Process Saf Prog 2008 [source]