JOURNAL OF CHEMICAL THERMODYNAMICS
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2022
·
IF 3.269
Jinkun Guo,Bo Jin,Shijin Chu,Rufang Peng
A different type of heat-flow calorimeter is developed to measure the energy of combustion. This calorimeter uses differential thermopile as the heat-flow sensor. The calorimeter and oxygen bomb have a special structure to ensure that the heat generated by combustion heat is slowly transferred to the thermopile, and the temperature of the outside interface of the thermopile is constant. The calorific coefficient is determined by chemical calibration, providing for the chemical calibration S =(64.806 ± 0.029) μV mW −1 , which means uncertainty is 0.05 % for calibration. The combustion enthalpies of anthracene and naphthalene are measured by using this calorimeter, and the results agree with the literature values or recommended values.
研究领域:
热化学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2016
·
IF 4.836
Qi Sun,Lin Jiang,Liang Gong,Jin-Hua Sun
During PUREX spent nuclear fuel reprocessing, mixture of tributyl phosphate (TBP) and hydrocarbon solvent are employed as organic solvent to extract uranium in consideration of radiation contaminated safety and resource recycling, meanwhile nitric acid is utilized to dissolve the spent fuel into small pieces. However, once TBP contacts with nitric acid or nitrates above 130 °C, a heavy “red oil” layer would occur accompanied by thermal runaway reactions, even caused several nuclear safety accident. Considering nitric acid volatility and weak exothermic detection, C80 micro calorimeter technique was used in this study to investigate thermal decomposition of TBP mixed with nitric acid. Results show that the concentration of nitric acid greatly influences thermal hazard of the system by direct reactions. Even with a low heating rate, if the concentration of nitric acid increases due to evaporation of water or improper operations, thermal runaway in the closed system could start at a low temperature.
研究领域:
化学工程
·
核能安全
·
热分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2013
·
IF 2.297
Qiu-Yue Kang,Qing Song,Sa-Ying Li,Zhi-Hong Liu
Two pure borophosphates microporous materials, K[ZnBP 2 O 8 ] and NH 4 [ZnBP 2 O 8 ], have been synthesized and characterized by XRD, FT-IR, DTA-TG techniques and chemical analysis. The molar enthalpies of solution of K[ZnBP 2 O 8 ](s) and NH 4 [ZnBP 2 O 8 ](s) in 3 mol · dm −3 HCl(aq), of KCl/NH 4 Cl(s) in (HCl + H 3 BO 3 )(aq), and of Zn(PO 3 ) 2 (s) in (HCl + H 3 BO 3 + KCl/NH 4 Cl)(aq) were measured by microcalorimeter at T = 298.15 K, respectively. With the incorporation of the previously determined enthalpy of solution of H 3 BO 3 (s) in 3 mol · dm −3 HCl(aq), together with the use of the standard molar enthalpies of formation for Zn(PO 3 ) 2 (s), KCl(s), NH 4 Cl(s), H 3 BO 3 (s) and H 2 O(l), the standard molar enthalpies of formation of −(3184.0 ± 1.2) kJ · mol −1 for K[ZnBP 2 O 8 ] and −(3067.6 ± 1.2) kJ · mol −1 for NH 4 [ZnBP 2 O 8 ] at T = 298.15 K was obtained on the basis of the appropriate thermochemical cycles.
研究领域:
无机化学
·
物理化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2019
·
IF 2.29
Jun-Feng Wang,Pan Liang
A pure barium borate of BaB 8 O 11 (OH) 4 ·3H 2 O has been synthesized and characterized by XRD, FT-IR, TGA, and chemical analysis. The molar enthalpies of solution of BaB 8 O 11 (OH) 4 ·3H 2 O in 1 mol dm −3 HCl(aq), and Ba(OH) 2 ·8H 2 O in the mixture solvent of {2.00 cm 3 of 1 mol·dm −3 HCl + H 3 BO 3 (aq)} were measured by microcalorimeter at T = 298.15 K, respectively. With the use of previously determined enthalpy of solution of H 3 BO 3 (s) in 1 mol·dm −3 HCl(aq), and the standard molar enthalpies of formation for Ba(OH) 2 ·8H 2 O(s), H 3 BO 3 (s), and H 2 O(l), the standard molar enthalpy of formation of −(7500.6 ± 6.5) kJ·mol −1 at T = 298.15 K was obtained based on an appropriate thermochemical cycle. Moreover, the molar enthalpy of formation of −6091.7 kJ mol −1 for [B 8 O 11 (OH) 4 ] 2− was estimated by a group contribution method, which was used to predict the Δ f H m o of a series of alkaline-earth metal borates for MB 8 O 11 (OH) 4 (M = Ca, Sr, Ba).
研究领域:
物理化学
·
无机化学
·
热化学
✓ 已验证
DOI
高影响因子
THERMOCHIMICA ACTA
·
2019
·
IF 2.251
Shijie Zhang,Jiaoqiang Zhang,Huimin Shi,Zhenguo Gao,Kaichang Kou
The polyacrylonitrile- b -poly(hydroxyethyl acrylate) (PAN- b -PHEA) was synthesized of polyacrylonitrile-TeMe (PAN-TeMe) and 2-Hydroxyethyl acrylate (HEA) via organotellurium-mediated living radical polymerization (TERP), and the PAN-TeMe and PAN- b -PHEA were characterized by several methods. A Calvet micro-calorimeter was used to investigate the polymerization of PAN-TeMe and HEA at different temperatures (358.15 K, 363.15 K, 368.15 K, 373.15 K, 378.15 K and 383.15 K). The kinetic equations of polymerization at different temperatures were obtained, and the apparent activation energy ( E ) of polymerization is 16.43±0.17 kJ∙mol −1 and the pre-exponential factor ( A ) is 0.6845±0.0366 s −1 . Furthermore, the thermodynamic parameters including the standard molar Gibbs free energy of activation ( Δ G ≠ θ ), the standard molar enthalpy of activation ( Δ H ≠ θ ) and the standard molar entropy of activation ( Δ S ≠ θ ) are acquired.
研究领域:
高分子化学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）