The porous cubic yttrium oxides with high specific surface area were prepared yttrium nitrate and its complex formed with methyl salicylate. The specific surface area by the explosive decomposition of and properties o...The porous cubic yttrium oxides with high specific surface area were prepared yttrium nitrate and its complex formed with methyl salicylate. The specific surface area by the explosive decomposition of and properties of powders synthesized at various temperatures were characterized using BET, X-ray diffraction （XRD）, infrared spectra （IR）, and scanning electron microscopy （SEM）. The results indicate that the highest specific surface area is found to be 65.37 m^2·g^-1 at the calcination temperature of 600 ℃, and then decreases to 20.33 m2· g^- 1 with the calcination temperature rising from 600 to 900 ℃. The powders show strong surface activity for adsorping water and carbon dioxide in air, which also decreases with the rising calcination temperature. The drop both on the surface area and surface activity of samples at higher temperatures may be due to pore-narrowing（sintering） effects.展开更多
The explosion characteristics of chlorine dioxide gas have been studied for the first time in a cylindrical exploder with a shell capacity of 201. The experimental results have indicated that the lower concentration l...The explosion characteristics of chlorine dioxide gas have been studied for the first time in a cylindrical exploder with a shell capacity of 201. The experimental results have indicated that the lower concentration limit for the explosive decomposition of chlorine dioxide gas is 9.5% （[ClO2]/[air]）, whereas there is no corresponding upper concentration limit. The maximum pressure of explosion relative to the initial pressure was measured as 0.024 MPa at 10% ClO2 and 0.641 MPa at 90% ClO2. The induction time （the time from the moment of sparking to explosion） at 10% ClO2 was 2195 ms, but at 90% ClO2 the induction time was just 8 ms. The explosion reaction mechanism of ClO2 is of a degenerate chain-branching type involving the formation of a stable intermediate （Cl2O3）, from which the chain branching occurs.展开更多
A new crystal form of diammonium 5,5＇-bistetrazole-1,1＇-diolate （1） was prepared by two novel methods and fully characterized by using IR, NMR spectroscopy, elementary analysis, single crystal X-ray crystallograph...A new crystal form of diammonium 5,5＇-bistetrazole-1,1＇-diolate （1） was prepared by two novel methods and fully characterized by using IR, NMR spectroscopy, elementary analysis, single crystal X-ray crystallography and thermal gravity/differential thermal analysis （TG/DTA）. Crystalline 1 was found as monoclinic and space group of P21/c （14）. The TG/DTA analysis showed that the decomposition temperature of 1 was 287.8℃ with a mass loss of 91.2% in the range of 220-300℃ at a heating rate of 5℃/min. The sensitivities test towards impact, friction of 1 indicated that 1 has much lower sensitivities than those of RDX/HMX and is comparable to those of TNT, which suggested that 1 could be used as a good candidate of new insensitive energetic compound.展开更多
文摘The porous cubic yttrium oxides with high specific surface area were prepared yttrium nitrate and its complex formed with methyl salicylate. The specific surface area by the explosive decomposition of and properties of powders synthesized at various temperatures were characterized using BET, X-ray diffraction （XRD）, infrared spectra （IR）, and scanning electron microscopy （SEM）. The results indicate that the highest specific surface area is found to be 65.37 m^2·g^-1 at the calcination temperature of 600 ℃, and then decreases to 20.33 m2· g^- 1 with the calcination temperature rising from 600 to 900 ℃. The powders show strong surface activity for adsorping water and carbon dioxide in air, which also decreases with the rising calcination temperature. The drop both on the surface area and surface activity of samples at higher temperatures may be due to pore-narrowing（sintering） effects.
基金supported by the National Natural Science Foundation of China (No.50774068) and Shanxi Provincial Science and Technology Department,China.
文摘The explosion characteristics of chlorine dioxide gas have been studied for the first time in a cylindrical exploder with a shell capacity of 201. The experimental results have indicated that the lower concentration limit for the explosive decomposition of chlorine dioxide gas is 9.5% （[ClO2]/[air]）, whereas there is no corresponding upper concentration limit. The maximum pressure of explosion relative to the initial pressure was measured as 0.024 MPa at 10% ClO2 and 0.641 MPa at 90% ClO2. The induction time （the time from the moment of sparking to explosion） at 10% ClO2 was 2195 ms, but at 90% ClO2 the induction time was just 8 ms. The explosion reaction mechanism of ClO2 is of a degenerate chain-branching type involving the formation of a stable intermediate （Cl2O3）, from which the chain branching occurs.
文摘A new crystal form of diammonium 5,5＇-bistetrazole-1,1＇-diolate （1） was prepared by two novel methods and fully characterized by using IR, NMR spectroscopy, elementary analysis, single crystal X-ray crystallography and thermal gravity/differential thermal analysis （TG/DTA）. Crystalline 1 was found as monoclinic and space group of P21/c （14）. The TG/DTA analysis showed that the decomposition temperature of 1 was 287.8℃ with a mass loss of 91.2% in the range of 220-300℃ at a heating rate of 5℃/min. The sensitivities test towards impact, friction of 1 indicated that 1 has much lower sensitivities than those of RDX/HMX and is comparable to those of TNT, which suggested that 1 could be used as a good candidate of new insensitive energetic compound.
