Quantum mechanics and molecular dynamics are used to simulate guanidinium ionic liquids. Results show that the stronger interaction exists between guanidine cation and chlorine anion with interaction energy about 109....Quantum mechanics and molecular dynamics are used to simulate guanidinium ionic liquids. Results show that the stronger interaction exists between guanidine cation and chlorine anion with interaction energy about 109.216 kcal/mol. There are two types of spatial distribution for the title system: middle and top. Middle mode is a more stable conformation according to energy and geometric distribution. It is also verified by radial distribution function. The continuous increase of carbon dioxide (CO2) does not affect the structure of ionic liquids, but CO2 molecules are always captured by the cavity of ionic liquids.展开更多
The chemical structure evolution of coal,which is important for understanding coalification and the accompanying volatile and possible oil generation,is generally thought to be influenced by temperature,time and confi...The chemical structure evolution of coal,which is important for understanding coalification and the accompanying volatile and possible oil generation,is generally thought to be influenced by temperature,time and confining pressure.Though evidence concerning the impacts of stress on the chemical structure has accumulated for many years and some hypotheses have been proposed,the mechanism remains controversial.Recent years have seen a breakthrough in mechanochemistry,which proves that stress can act on the molecule directly to initiate or accelerate reactions by deforming the chemical bonds.The progress in mechanochemistry gives researchers incentive to consider how stress works on the chemical structure of coals.Preliminary quantum chemical calculations have been performed on the macromolecule of anthracite to explain the mechanism of gas generation during the deformation experiments at low temperatures.This paper briefly reviews the evidence regarding the impacts of stress on the chemical structure of coals and introduces the recent achievements in the mechanism research.To further investigate this problem,more work should be undertaken by researchers from both geology and quantum chemistry fields.展开更多
In the past decades, combustion chemistry research grew rapidly due to the development of combustion diagnostic methods,quantum chemistry methods, kinetic theory, and computational techniques. A lot of kinetic models ...In the past decades, combustion chemistry research grew rapidly due to the development of combustion diagnostic methods,quantum chemistry methods, kinetic theory, and computational techniques. A lot of kinetic models have been developed for fuels from hydrogen to transportation fuel surrogates. Besides, multi-scale research method has been widely adopted to develop comprehensive models, which are expected to cover combustion conditions in real combustion devices. However, critical gaps still remain between the laboratory research and real engine application due to the insufficient research work on high pressure and low temperature combustion chemistry. Besides, there is also a great need of predictive pollutant formation model. Further development of combustion chemistry research depends on a closer interaction of combustion diagnostics, theoretical calculation and kinetic model development. This paper summarizes the recent progress in combustion chemistry research briefly and outlines the challenges and perspectives.展开更多
基金ACKNOWLEDGMENTS This work was supported by the Open Project Program of Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education, Hunan University of Science and Technology, China (No.E21104), the National Natural Science Foundation of China (No.21201062 and No.21172066), and the International Cooperation Project (No.2013DFG60060).
文摘Quantum mechanics and molecular dynamics are used to simulate guanidinium ionic liquids. Results show that the stronger interaction exists between guanidine cation and chlorine anion with interaction energy about 109.216 kcal/mol. There are two types of spatial distribution for the title system: middle and top. Middle mode is a more stable conformation according to energy and geometric distribution. It is also verified by radial distribution function. The continuous increase of carbon dioxide (CO2) does not affect the structure of ionic liquids, but CO2 molecules are always captured by the cavity of ionic liquids.
基金supported by the National Key Research and Development Program of China(2016YFC0600401)the National Natural Science Foundation of China(41030422)
文摘The chemical structure evolution of coal,which is important for understanding coalification and the accompanying volatile and possible oil generation,is generally thought to be influenced by temperature,time and confining pressure.Though evidence concerning the impacts of stress on the chemical structure has accumulated for many years and some hypotheses have been proposed,the mechanism remains controversial.Recent years have seen a breakthrough in mechanochemistry,which proves that stress can act on the molecule directly to initiate or accelerate reactions by deforming the chemical bonds.The progress in mechanochemistry gives researchers incentive to consider how stress works on the chemical structure of coals.Preliminary quantum chemical calculations have been performed on the macromolecule of anthracite to explain the mechanism of gas generation during the deformation experiments at low temperatures.This paper briefly reviews the evidence regarding the impacts of stress on the chemical structure of coals and introduces the recent achievements in the mechanism research.To further investigate this problem,more work should be undertaken by researchers from both geology and quantum chemistry fields.
基金supported by the National Natural Science Foundation of China(91541201,91641205,51622605)the National Basic Research Program of China(2013CB834602)+1 种基金the National Postdoctoral Program for Innovative Talents(BX201600100)China Postdoctoral Science Foundation(2016M600312)
文摘In the past decades, combustion chemistry research grew rapidly due to the development of combustion diagnostic methods,quantum chemistry methods, kinetic theory, and computational techniques. A lot of kinetic models have been developed for fuels from hydrogen to transportation fuel surrogates. Besides, multi-scale research method has been widely adopted to develop comprehensive models, which are expected to cover combustion conditions in real combustion devices. However, critical gaps still remain between the laboratory research and real engine application due to the insufficient research work on high pressure and low temperature combustion chemistry. Besides, there is also a great need of predictive pollutant formation model. Further development of combustion chemistry research depends on a closer interaction of combustion diagnostics, theoretical calculation and kinetic model development. This paper summarizes the recent progress in combustion chemistry research briefly and outlines the challenges and perspectives.