Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existen...Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existence of aromatic structure,heteroatom structure and fat structure in coal.MS(materials studio)software was used to optimize and construct a 3D molecular structure model of coal.A method for establishing a coal molecular structure model was formed,which was“determination of key structures in coal,construction of planar molecular structure model,and optimization of three-dimensional molecular structure model”.The structural differences were compared and analyzed.The results show that with the increase of coal rank,the dehydrogenation of cycloalkanes in coal is continuously enhanced,and the content of heteroatoms in the aromatic ring decreases.The heteroatoms and branch chains in the coal are reduced,and the structure is more orderly and tight.The stability of the structure is determined by theπ-πinteraction between the aromatic rings in the nonbonding energy EN.Key Stretching Energy The size of EB determines how tight the structure is.The research results provide a method and reference for the study of the molecular structure of medium and high coal ranks.展开更多
嵌入式计算机系统作为计算机应用的一个重要领域,应用广泛。Windows XP Embedded(XPE)具备XP与诸多嵌入式系统的优点。首先简单介绍XPE操作系统的特点,提出采用Windows XP Embedded Studio Tools设计工具在Windows XP Professinal操作...嵌入式计算机系统作为计算机应用的一个重要领域,应用广泛。Windows XP Embedded(XPE)具备XP与诸多嵌入式系统的优点。首先简单介绍XPE操作系统的特点,提出采用Windows XP Embedded Studio Tools设计工具在Windows XP Professinal操作系统开发站下构建XPE操作系统。最后讨论XPE操作系统的具体应用。展开更多
： The superfine CaCO3 powder coated with SiO2 was synthesized. Through XRD technique, the cell parameters and crystallite size of reference and coated CaCO3 were calculated. SiO2 present in the state of amorphous and...： The superfine CaCO3 powder coated with SiO2 was synthesized. Through XRD technique, the cell parameters and crystallite size of reference and coated CaCO3 were calculated. SiO2 present in the state of amorphous and prevent the agglomeration and growth of CaCO3 micro-crystal. By comparing the result of XPS analysis of reference compound to coated sample, CaCO3 has been coated successfully with SiO2. The thickness of the coating is about 2.4～ 3.4nm. From the difference(0.8eV increase) of the binding energy of Ca2p, we presume that the bind Si-O-Ca has formed in the surface of CaCO3.展开更多
基金supported by the National Natural Science Foundation of China(41872174 and 42072189)the Program for Innovative Research Team(in Science and Technology)in the Universities of Henan Province,China(21IRTSTHN007)the Program for Innovative Research Team(in Science and Technology)of Henan Polytechnic University(T2020-4)。
文摘Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existence of aromatic structure,heteroatom structure and fat structure in coal.MS(materials studio)software was used to optimize and construct a 3D molecular structure model of coal.A method for establishing a coal molecular structure model was formed,which was“determination of key structures in coal,construction of planar molecular structure model,and optimization of three-dimensional molecular structure model”.The structural differences were compared and analyzed.The results show that with the increase of coal rank,the dehydrogenation of cycloalkanes in coal is continuously enhanced,and the content of heteroatoms in the aromatic ring decreases.The heteroatoms and branch chains in the coal are reduced,and the structure is more orderly and tight.The stability of the structure is determined by theπ-πinteraction between the aromatic rings in the nonbonding energy EN.Key Stretching Energy The size of EB determines how tight the structure is.The research results provide a method and reference for the study of the molecular structure of medium and high coal ranks.
文摘嵌入式计算机系统作为计算机应用的一个重要领域,应用广泛。Windows XP Embedded(XPE)具备XP与诸多嵌入式系统的优点。首先简单介绍XPE操作系统的特点,提出采用Windows XP Embedded Studio Tools设计工具在Windows XP Professinal操作系统开发站下构建XPE操作系统。最后讨论XPE操作系统的具体应用。
文摘： The superfine CaCO3 powder coated with SiO2 was synthesized. Through XRD technique, the cell parameters and crystallite size of reference and coated CaCO3 were calculated. SiO2 present in the state of amorphous and prevent the agglomeration and growth of CaCO3 micro-crystal. By comparing the result of XPS analysis of reference compound to coated sample, CaCO3 has been coated successfully with SiO2. The thickness of the coating is about 2.4～ 3.4nm. From the difference(0.8eV increase) of the binding energy of Ca2p, we presume that the bind Si-O-Ca has formed in the surface of CaCO3.
