JOURNAL OF CHEMICAL THERMODYNAMICS
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2024
·
IF 2.2
Yufeng Tang,Qichao Yang,Zhanping Qiao
The phase equilibrium of ternary systems RbX/CsX + CuX 2 + H 2 O (X = Cl, Br) at T = 298.15 K were investigated by the isothermal dissolution equilibrium method, in which the composition of equilibrium solid phases was determined by the Schreinemaker’s wet residue method. In the system RbCl + CuCl 2 + H 2 O, there were three crystallization regions corresponding to RbCl, Rb 2 CuCl 4 ·2H 2 O and CuCl 2 ·2H 2 O, respectively. Five crystallization fields corresponding to CsCl, CsCuCl 3 , Cs 3 Cu 2 Cl 7 ·2H 2 O, Cs 2 CuCl 4 and CuCl 2 ·2H 2 O were formed in the system CsCl + CuCl 2 + H 2 O. The ternary system RbBr + CuBr 2 + H 2 O had three crystalline regions corresponding to RbBr, Rb 2 CuBr 4 ·2H 2 O and CuBr 2 . In the system CsBr + CuBr 2 + H 2 O, the solid-phases of CsCuBr 3 , Cs 2 CuBr 4 , besides CsBr and CuBr 2 , were discovered. The results were compared with available literature data for cesium bromide/copper bromide salt-water system. The seven new solid phase were characterized using the X-ray diffraction method and thermogravimetric/differential analysis. The dissolution enthalpies of Rb 2 CuCl 4 ·2H 2 O, Rb 2 CuBr 4 ·2H 2 O, CsCuCl 3 , Cs 3 Cu 2 Cl 7 ·2H 2 O, Cs 2 CuCl 4 , CsCuBr 3 and Cs 2 CuBr 4 at T = 298.15 K were measured. Their standard enthalpies of formation were obtained, and the results were in order with −(1714.4 ± 3.2) kJ·mol −1 , −(1533.6 ± 3.3) kJ·mol −1 , −(697.8 ± 3.1) kJ·mol −1 , −(2418.9 ± 6.1) kJ·mol −1 , −(1134.8 ± 3.2) kJ·mol −1 , −(563.5 ± 3.2) kJ·mol −1 and −(966.2 ± 3.3) kJ·mol −1 , respectively.
研究领域:
物理化学
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无机化学
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热力学
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Wentao Wang,Xiaolong Guo,Weiwei Geng,Kanghui Wang,Wenzheng Zhang,Lu Liu,Yuang Zhang,Bingtao Tang,Liming Ding
High performance continuous phase change fibers are of great significance to promote the development and application of functional fibers. But, it is still a challenge to fabricate continuous phase change fibers with high phase transition enthalpy. Herein, a kind of continuous polyurethane phase change fibers (PUPCFs) was first reported which was prepared through melt spinning from the synthesized polyurethane phase change materials (PUPCMs). PUPCFs not only overcomes the leakage problem of phase change materials, but also exhibits high latent heat (110.54 J/g), superior mechanical properties (maximum strain, ∼141.83 %), outstanding fatigue resistance, and good thermal cycle stability. Furthermore, a phase change thermoregulation textile (PUPCT/PDMS) with high enthalpy, hydrophobicity and breathability can be obtained by weaving PUPCFs and then coating with polydimethylsiloxane (PDMS). This work can provide a new idea for efficient and economical production of continuous phase change fibers and opens up opportunities for wearable thermal management textiles.
研究领域:
材料科学
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纺织工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2025
·
IF 9.8
Fengyi Yang,Yimin Xuan,Xianglei Liu
Eutectic salts are widely utilized as latent heat storage materials in various thermal energy storage and management applications. However, developing efficient and accurate methods to predict the thermophysical properties of molten salts and guide their design remains a significant challenge. This study focuses on thermal properties, constructing an element gene feature database, and introducing an integrated machine-learning strategy for the design, screening, and evaluation of eutectic salts. Marginal contribution analysis reveals that the melting point is primarily influenced by features related to structural stability, while the fusion enthalpy is strongly associated with features affecting atomic bonding strength. Based on these insights, five novel eutectic salts are designed and experimentally validated. Among them, NaCl-NaF (66.0–34.0 mol%) exhibits a melting point of 683.7 °C and a fusion enthalpy of 588.8 J/g. High-temperature testing demonstrates that the prediction accuracies for the melting point and fusion enthalpy of the five salts are 94.49 % and 95.01 %, respectively. This study presents an effective and efficient approach for the precise targeted design of novel eutectic salts, offering expanded possibilities and options for the efficient utilization of renewable energy.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2021
·
IF 2.694
Linmao Tang,Yuan Guo,Zuoxiang Zeng,Weilan Xue
The density and liquid heat capacity of propyl cinnamate were measured in the temperature range from 290.15 to 503.15 K by a pycnometer and automatic adiabatic calorimeter and correlated with temperature by the linear equation and quadratic polynomial, respectively. Vapor pressure data of propyl cinnamate were determined by the ebulliometric method at 419.15–559.15 K, and they are in accordance with the Antoine equation. The vaporization enthalpy ΔvapH (Tb) of propyl cinnamate at normal boiling point was attained based on the Clausius–Clapeyron equation. The standard enthalpy of vaporization ΔvapH (298.15 K) was calculated by the Othmer method and verified by the Watson relation.
研究领域:
物理化学
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热力学
✓ 已验证
产品关联
DOI
高影响因子
Soft Matter
·
2015
·Vol. 11
·期 14
·2885-2892
·
IF 4.029
Dashuang Fan,Peizhu Zheng,Yuanming Ma,Tianxiang Yin,Jihua Zhao,Weiguo Shen
The concentration-dependent enthalpies of mixing for water/sodium bis(2-ethylhexyl)-sulfosuccinate (AOT)/n-alkane microemulsions with different water contents ω0 and chain lengths n of n-alkane were determined by isothermal titration microcalorimetry (ITC) and flow-mixing microcalorimetry at 298.15 K and used to calculate the interaction enthalpies (−ΔHC) between the droplets. It was found that −ΔHC increased with ω0, and changed from negative to positive at about ω0 = 10. The investigation of the dependence of −ΔHC on n revealed that the values of −ΔHC were negative and had a minimum for ω0 = 5; while they were positive and had a maximum for ω0 = 15. These phenomena were discussed based on the competition of the overlapping contribution of the surfactant tails between two neighbouring droplets and the penetration contribution of the solvent molecules into the surfactant tails. These results indicated the important role of entropy in the stability of the microemulsion systems.
研究领域:
化学
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物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2016
·
IF 1.835
Chunyan Ma,Yanhua Guo,Dongxue Li,Jianpeng Zong,Xiaoyan Ji,Chang Liu,Xiaohua Lu
The molar enthalpies of mixing for binary systems of choline chloride (chcl)/urea deep eutectic solvents (mole ratios of 1:1.5, 1:2, and 1:2.5) with water were measured at 308.15 and 318.15 K under atmospheric pressure with an isothermal calorimeter. The binary mixture of (chcl/urea (1:2.5) + water) showed endothermic behavior over the entire range of compositions, while the binary mixtures of (chcl/urea (1:1.5) + water) and (chcl/urea (1:2) + water) showed endothermic behavior first and then was changed to be exothermic with increasing content of deep eutectic solvents. The Redlich–Kister (RK) equation and the nonrandom two-liquid (NRTL) model were used to fit experimental molar enthalpies of mixing. The NRTL model with the fitted parameters was further used to predict the vapor pressure for the three systems and was compared with the experimental data from literature. For the binary mixtures of (chcl/urea (1:2) + water), the predicted vapor pressure agreed well with the experimental data only when the temperature was lower than 333.15 K and the mole fraction of chcl/urea (1:2) was lower than 0.1. Otherwise, the deviation increased greatly with an increase of the amount of chcl/urea (1:2).
研究领域:
化学热力学
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2015
·
IF 2.037
Fang Zhang,Yaocun Tang,Long Wang,Li Xu,Guoji Liu
The solubility of 2-methylnaphthalene in different organic solvents was experimentally studied by the equilibrium method at temperatures from (278.15 to 303.15) K under atmospheric pressure. The solubility of 2-methylnaphthalene in all solvents increased with the increasing temperature. The solubility data were correlated with four thermodynamic models including the van’t Hoff equation, modified Apelblat equation, λh equation, and Wilson model. It was found that the calculated solubility with modified Apelblat equation provided a good agreement with the experimental values for the solubility behavior of 2-methylnaphthalene. The thermodynamic properties of the standard dissolution enthalpy, standard entropy, and the standard mole Gibbs free energy were evaluated based on the van’t Hoff analysis. The values of enthalpy of dissolution are positive, which indicate that the dissolution process of 2-methylnaphthalene in different organic solvents is endothermic.
研究领域:
化学
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
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2016
·
IF 2.196
Lejun Feng,Danxing Zheng,Weijia Huang
In this work, three new working pairs, {fluoroethane (HFC161) + dimethylether tetraethylene glycol (DMETEG)}, {HFC161 + dimethylether triethylene glycol (DMETrEG)} and {HFC161 + dimethylether diethylene glycol (DMEDEG)}, are proposed for absorption power cycle. The working pairs are assessed from both thermodynamics and thermokinetic perspective. By combining the microcalorimetry and isothermal synthesis methods, an experimental apparatus was developed to simultaneously obtain the microcalorimetry and vapour–liquid equilibrium data. Then, the solubility and absorption enthalpy data of the three new working pairs were sync-measured at 303.15 K by this sync-measurement experimental apparatus. The thermodynamics data indicated that the affinities of the three working pairs increased from strong to weak in the following order: HFC161 + DMETEG > HFC161 + DMETrEG > HFC161 + DMEDEG. Then the thermokinetic parameters of the absorption rate constant and activation energy were analysed based on the thermokinetic experiment at (303.15, 313.15, 323.15, and 333.15) K. As a result, the affinities of the three working pairs are consistent with the previous thermodynamics study. In addition, the intermolecular interactions within the three systems were analysed according to the intermolecular hydrogen bonds; overall, the (HFC161 + DMETEG) system is considered to be the potential option for applications.
研究领域:
化学工程
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热力学
✓ 已验证
产品关联
DOI
高影响因子
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
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 14
·2072
·
IF 5.3
Xu Zhang,Bo Tian,Zhiheng Ma,He Wang,Zhixuan Cheng,Jiaqiang Xu
As a volatile air pollutant, formaldehyde can enter people’s living environment through interior decoration, furniture and paint, causing serious harm to human health. Therefore, it is necessary to develop a sensor for the real-time detection of formaldehyde in low concentrations. According to the chemical interaction between amino groups and formaldehyde, a MIL-101(Cr) aminated-material-based formaldehyde cantilever sensor was prepared, of which ethylenediamine- functionalized MIL-101(Cr) named ED-MIL-101(Cr)) showed the best gas sensing performance. Using quasi-in situ infrared spectroscopy, ED-MIL-101(Cr) was found bound to formaldehyde through a Schiff base. The adsorption enthalpy of formaldehyde-bound ED-MIL-101(Cr) was −52.6 kJ/mol, which corresponds to weak chemical adsorption, so the material showed good selectivity. In addition, ED-MIL-101(Cr) has the most active sites, so its response value to formaldehyde is larger and it takes longer to reach saturation adsorption than bare MIL-101(Cr). Through the research on the gas sensing performance of functionalized MIL-101(Cr) material, we found that it has a strong application potential in the field of formaldehyde monitoring, and the material performance can be quantitatively and accurately evaluated through combining calculation and experimentation for understanding the gas sensing mechanism.
研究领域:
材料科学
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环境科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2012
·
IF 2.422
Yang Lv,Ning Li,Mei Tang,Zhi-Hong Liu
Two pure hydrated aluminoborates with microporous structure, K 2 [Al(B 5 O 10 )] · 4H 2 O and (NH 4 ) 2 [Al(B 5 O 10 )] · 4H 2 O, have been synthesized and characterized by XRD, FT-IR, DTA-TG techniques and chemical analysis. The molar enthalpies of solution of K 2 [Al(B 5 O 10 )] · 4H 2 O (s) and (NH 4 ) 2 [Al(B 5 O 10 )] · 4H 2 O (s) in 1 mol · dm −3 HCl (aq) were measured to be −(88.65 ± 0.25) kJ · mol −1 and −(93.37 ± 0.25) kJ · mol −1 , respectively. The molar enthalpies of solution of AlCl 3 ·6H 2 O (s) in (HCl + H 3 BO 3 + KCl) (aq) and in (HCl + H 3 BO 3 + NH 4 Cl) (aq) were measured, respectively. With the incorporation of the previously determined enthalpy of solution of H 3 BO 3 (s) in 1 mol · dm −3 HCl (aq), together with the use of the standard molar enthalpies of formation for AlCl 3 ·6H 2 O (s), KCl (s)/NH 4 Cl (s), H 3 BO 3 (s), HCl (aq), and H 2 O (l), the standard molar enthalpy of formation of −(6029.8 ± 4.1) kJ · mol −1 for K 2 [Al(B 5 O 10 )] · 4H 2 O (s) and −(5775.0 ± 4.1) kJ · mol −1 for (NH 4 ) 2 [Al(B 5 O 10 )] · 4H 2 O (s) at T = 298.15 K were obtained on the basis of the appropriate thermochemical cycles. Moreover, Δ f H m o ([Al(B 5 O 10 )] 2− ) of −4355.3 kJ · mol −1 has also been estimated by a group contribution method, which can be used to predict the standard molar enthalpies of formation of other aluminoborates containing [Al(B 5 O 10 )] 2− anionic framework.
研究领域:
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2024
·
IF 2
Jumei Xu,Yu Qi,Zuoxiang Zeng,Weilan Xue
The density and the heat capacity of (E,E)-methyl sorbate (MS) were measured from 286.35 to 433.25 K using a pycnometer and an adiabatic calorimeter, respectively. The saturated vapor pressure of MS was determined by the ebulliometric method from 344.95 to 455.15 K and correlated by the Antoine equation with an average relative deviation of 1.68%. The enthalpy of vaporization of MS at the normal boiling point was figured out to be 44.29 kJ mol–1 according to the Clausius–Clapeyron equation. Based on the Othmer method, the standard enthalpy of vaporization of MS was obtained using three substances as a reference, and the calculated results were further verified by the Watson relation and the Clarke–Glew equation.
研究领域:
物理化学
·
热力学
✓ 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）