A new energetic complex, Ni(3,4'-Hbpt)2(Hoba)2(H20)2 (3,4'-Hbpt = 3-(3-pyridyl)- 5-(4'-pyridyl)-l-H-l,2,4-triazole and H2oba = 4,4'-oxybis(benzoic acid)), has been synthesized by hydrothermal reactio...A new energetic complex, Ni(3,4'-Hbpt)2(Hoba)2(H20)2 (3,4'-Hbpt = 3-(3-pyridyl)- 5-(4'-pyridyl)-l-H-l,2,4-triazole and H2oba = 4,4'-oxybis(benzoic acid)), has been synthesized by hydrothermal reaction and characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric analyses and X-ray powder diffraction. Single-crystal X-ray diffraction analysis indicates that the complex belongs to the monoclinic system, space group P2j/c with a = 10.2357(9), b = 24.594(2), c = 10.4225(9)/k, β = 114.0110(10)°, V = 2396.7(4) A3, Dc = 1.460 g/cm3,μ = 0.482 mm-1, Mr = 1053.63, F(000) = 1088, Z = 2, the final R = 0.0358 and wR = 0.0973 with I 〉 2σ(I). Both 3,4'-Hbpt and H2oba ligands adopt monodentate modes linking one Ni(II) ion to form a 0D motif. Furthermore, the 0D motifs are linked into a 3D supramolecular architecture with hydrogen bonds. In addition, the catalytic performance for thermal decomposition of the efficacy of ammonium perchlorate (AP) is explored by differential scanning calorimetry (DSC), which indicates that the complex is a good candidate for a promoter of the thermal decomposition of ammonium perchlorate.展开更多
The decomposition kinetics of glucose was studied in high-temperature liquid water (HTLW) from 180 to 220℃ under a pressure of 10 MPa. It was found the main products from glucose decomposition were 5-hydroxymethylf...The decomposition kinetics of glucose was studied in high-temperature liquid water (HTLW) from 180 to 220℃ under a pressure of 10 MPa. It was found the main products from glucose decomposition were 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA). The decomposition kinetics of 5-HMF and stability of LA in HTLW were further investigated. A kinetic model for glucose decomposition was proposed accordingly. In the model, a series of first-order reactions with the consideration of parallel by-reactions were used to illustrate the decomposition of glucose. The decomposition activation energies of glucose, 5-HMF, and LA were evaluated as 118.85, 95.40, and 31.29 kJ·mol^-1, respectively.展开更多
Perovskite-type La0.8Sr0.2MnO3 was prepared by stearic acid gel combustion method.The obtained powders were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),scaning electron micro...Perovskite-type La0.8Sr0.2MnO3 was prepared by stearic acid gel combustion method.The obtained powders were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),scaning electron micrograph(SEM)and X-ray photoelectron spectroscopy(XPS)techniques.The catalytic activity of La0.8Sr0.2MnO3 was investigated on thermal decomposition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)by thermal gravity-differential scanning calorimetry(TG-DSC)techniques.The experimental results show that La0.8Sr0.2MnO3 is an effective catalyst for HMX thermal decomposition.The surface-adsorbed species such as H2O,OH - and adsorbed oxygen(Oad)could result in an advance in the onset temperature of HMX thermal decomposition.The mixture system of Mn 3+ and Mn 4+ ions and lattice oxygen could play key roles for the increase of the decomposition heat of HMX because these exothermic reactions could be catalyzed by La0.8Sr0.2MnO3 between CO and NOx(from the thermal decomposition of HMX)and the oxidation reaction of CO.According to the previous researches and our results,perovskite-type La0.8Sr0.2MnO3 may be used as a novel catalyst or modifier for nitrate ester plasticized polyether(NEPE)propellant.展开更多
The decomposition kinetics of glucose and 5-hydroxymethylfurfural catalyzed by copper chloride were measured in small volume high-pressure vessel batch reactors,at various temperatures from 423.15 K to 463.15 K and ca...The decomposition kinetics of glucose and 5-hydroxymethylfurfural catalyzed by copper chloride were measured in small volume high-pressure vessel batch reactors,at various temperatures from 423.15 K to 463.15 K and catalyst concentration from 0 to 0.08 mol·L-1.The results showed that their conversion went up with the increase of reaction temperature and catalyst concentration,resulting in higher yield of levulinic acid.By comparing the correlation coefficients,it was confirmed that both glucose and 5-hydroxymethylfurfural decomposition are first order reaction.By using first order kinetics equation,the activation energies of desired and undesired reaction were estimated,134.65 kJ·mol-1 and 144.1 kJ·mol-1 for glucose decomposition,131.97 kJ·mol-1 and 135.18 kJ·mol-1 for 5-hydroxymethylfurfural decomposition,respectively.This work would provide important basic data not only for the exploration of reaction mechanism of glucose decomposition,but also for the development of high activity and high selectivity catalyst.展开更多
The crystal of [Co(H2O)6]·(Hnip)2·(H2nip)2·(OMA)2·(H2O)8 has been cultured using direct method and characterized by X-ray single crystal diffractometry, elemental analysis and FTIR spectr...The crystal of [Co(H2O)6]·(Hnip)2·(H2nip)2·(OMA)2·(H2O)8 has been cultured using direct method and characterized by X-ray single crystal diffractometry, elemental analysis and FTIR spectroscopy. It crystallizes in triclinic system, P-1 space group with the cell parameters of a=0.7012(1) nm, b=1.1378(2) nm, c=1.6612(3) nm, α= 84.92(3)°, β=85.19(3)°, γ=85.91(3)°, V= 1.3128(5) nm^3, Z=1, Dc= 1.573 g·cm^-3. Final R indices [1〉2σ(I)] are: R1 =0.0279, wR2=0.0765 while R indices for all data are: R1 =0.0327, wR2=0.0806. The Co coordination octahadra are each surrounded by two Hnip, two H2nip, two DMA and eight water molecules that are linked by hydrogen bonds and π-π stacking interactions. Thermal analyses of DSC and TG-DTG have been performed on the complex to predict its thermal decomposition mechanism and determine the most probable kinetic model function using Kissinger, Ozawa, integral and differential methods.展开更多
基金Supported by the National Natural Science Foundation of China(No.21263019)
文摘A new energetic complex, Ni(3,4'-Hbpt)2(Hoba)2(H20)2 (3,4'-Hbpt = 3-(3-pyridyl)- 5-(4'-pyridyl)-l-H-l,2,4-triazole and H2oba = 4,4'-oxybis(benzoic acid)), has been synthesized by hydrothermal reaction and characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric analyses and X-ray powder diffraction. Single-crystal X-ray diffraction analysis indicates that the complex belongs to the monoclinic system, space group P2j/c with a = 10.2357(9), b = 24.594(2), c = 10.4225(9)/k, β = 114.0110(10)°, V = 2396.7(4) A3, Dc = 1.460 g/cm3,μ = 0.482 mm-1, Mr = 1053.63, F(000) = 1088, Z = 2, the final R = 0.0358 and wR = 0.0973 with I 〉 2σ(I). Both 3,4'-Hbpt and H2oba ligands adopt monodentate modes linking one Ni(II) ion to form a 0D motif. Furthermore, the 0D motifs are linked into a 3D supramolecular architecture with hydrogen bonds. In addition, the catalytic performance for thermal decomposition of the efficacy of ammonium perchlorate (AP) is explored by differential scanning calorimetry (DSC), which indicates that the complex is a good candidate for a promoter of the thermal decomposition of ammonium perchlorate.
基金Supported by the National Natural Science Foundation of China (20674068) and the Natural Science Foundation of Zhejiang Province (Y405157).
文摘The decomposition kinetics of glucose was studied in high-temperature liquid water (HTLW) from 180 to 220℃ under a pressure of 10 MPa. It was found the main products from glucose decomposition were 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA). The decomposition kinetics of 5-HMF and stability of LA in HTLW were further investigated. A kinetic model for glucose decomposition was proposed accordingly. In the model, a series of first-order reactions with the consideration of parallel by-reactions were used to illustrate the decomposition of glucose. The decomposition activation energies of glucose, 5-HMF, and LA were evaluated as 118.85, 95.40, and 31.29 kJ·mol^-1, respectively.
基金Supported by the National Natural Science Foundation of China (20671084)
文摘Perovskite-type La0.8Sr0.2MnO3 was prepared by stearic acid gel combustion method.The obtained powders were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),scaning electron micrograph(SEM)and X-ray photoelectron spectroscopy(XPS)techniques.The catalytic activity of La0.8Sr0.2MnO3 was investigated on thermal decomposition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)by thermal gravity-differential scanning calorimetry(TG-DSC)techniques.The experimental results show that La0.8Sr0.2MnO3 is an effective catalyst for HMX thermal decomposition.The surface-adsorbed species such as H2O,OH - and adsorbed oxygen(Oad)could result in an advance in the onset temperature of HMX thermal decomposition.The mixture system of Mn 3+ and Mn 4+ ions and lattice oxygen could play key roles for the increase of the decomposition heat of HMX because these exothermic reactions could be catalyzed by La0.8Sr0.2MnO3 between CO and NOx(from the thermal decomposition of HMX)and the oxidation reaction of CO.According to the previous researches and our results,perovskite-type La0.8Sr0.2MnO3 may be used as a novel catalyst or modifier for nitrate ester plasticized polyether(NEPE)propellant.
文摘The decomposition kinetics of glucose and 5-hydroxymethylfurfural catalyzed by copper chloride were measured in small volume high-pressure vessel batch reactors,at various temperatures from 423.15 K to 463.15 K and catalyst concentration from 0 to 0.08 mol·L-1.The results showed that their conversion went up with the increase of reaction temperature and catalyst concentration,resulting in higher yield of levulinic acid.By comparing the correlation coefficients,it was confirmed that both glucose and 5-hydroxymethylfurfural decomposition are first order reaction.By using first order kinetics equation,the activation energies of desired and undesired reaction were estimated,134.65 kJ·mol-1 and 144.1 kJ·mol-1 for glucose decomposition,131.97 kJ·mol-1 and 135.18 kJ·mol-1 for 5-hydroxymethylfurfural decomposition,respectively.This work would provide important basic data not only for the exploration of reaction mechanism of glucose decomposition,but also for the development of high activity and high selectivity catalyst.
基金Project supported by the National Natural Science Foundation of China (No. 20471008).
文摘The crystal of [Co(H2O)6]·(Hnip)2·(H2nip)2·(OMA)2·(H2O)8 has been cultured using direct method and characterized by X-ray single crystal diffractometry, elemental analysis and FTIR spectroscopy. It crystallizes in triclinic system, P-1 space group with the cell parameters of a=0.7012(1) nm, b=1.1378(2) nm, c=1.6612(3) nm, α= 84.92(3)°, β=85.19(3)°, γ=85.91(3)°, V= 1.3128(5) nm^3, Z=1, Dc= 1.573 g·cm^-3. Final R indices [1〉2σ(I)] are: R1 =0.0279, wR2=0.0765 while R indices for all data are: R1 =0.0327, wR2=0.0806. The Co coordination octahadra are each surrounded by two Hnip, two H2nip, two DMA and eight water molecules that are linked by hydrogen bonds and π-π stacking interactions. Thermal analyses of DSC and TG-DTG have been performed on the complex to predict its thermal decomposition mechanism and determine the most probable kinetic model function using Kissinger, Ozawa, integral and differential methods.