The oxidation behavior of Al2O3-30%TiCN-0.2%Y2O3 composite and its effect on high temperature bending strength was studied. The result indicates that the mass gain during static oxidation of the material under normal ...The oxidation behavior of Al2O3-30%TiCN-0.2%Y2O3 composite and its effect on high temperature bending strength was studied. The result indicates that the mass gain during static oxidation of the material under normal atmosphere follows the parabolic law. Oxide increases with increasing temperature and prolonging time. It has good oxidation resistance. The product of oxidation of the material is TiO2. Therefore, the volume of the material expands. The oxide film is destroyed because residual stress inside the oxide film is released. Proper oxidation is beneficial to the improvement of bending strength of Al2O3-30%TiCN-0.2%Y2O3 composite. The strength increase is up to 4.5%.展开更多
By the use of the 3/2 power law presented by Toba combined with the significant wave energy balance equation for wind wave, wind wave growth at a limited fetch is analytically investigated. The new wind wave growth re...By the use of the 3/2 power law presented by Toba combined with the significant wave energy balance equation for wind wave, wind wave growth at a limited fetch is analytically investigated. The new wind wave growth relations (WWGRs) are analytically derived with sheltering coefficient and wind drag coefficient as parameters. The geometrical average of observational values of sheltering coefficient and the arithmetic average of observational values of wind drag coefficient are applied to determine the new WWGRs. Comparisons with existing empirical WWGRs are made.展开更多
Wind input parameterizations proposed by Jeffreys, Sverdrup and Munk, and Plant are analyzed. It is found by analogy that the similarity of integrals of the three wind input parameterizations exists. Wave breaking dis...Wind input parameterizations proposed by Jeffreys, Sverdrup and Munk, and Plant are analyzed. It is found by analogy that the similarity of integrals of the three wind input parameterizations exists. Wave breaking dissipation parameterizations proposed by Tsikunov, Hasselmann, and Phillips are also analyzed. Likewise it is found by analogy that the similarity of integrals of the three dissipation parameterizations exists. The similarities of wind input and dissipation are applied to the investigation of the fetch-limited growth of wind waves, together with the 3/2 power law presented by Toba. Some semi-empirical formulas concerning the growth of wave height and period with fetch are presented. The results from the formulas are in good agreement with previous field observations.展开更多
Red phosphorus(RP)is beneficial to industrialization due to its rich resources,chemical stability and environmental friendliness.However,the low electronic conductivity and large volume expansion limit its application...Red phosphorus(RP)is beneficial to industrialization due to its rich resources,chemical stability and environmental friendliness.However,the low electronic conductivity and large volume expansion limit its application for energy storage.Herein,we first used RP to prepare a novel bouquet-like Co_(3)(HPO_(4))_(2)(OH)_(2) by the hydrothermal approach as cathode materials for hybrid supercapacitors(HSC),which delivered a large specific capacity(119.2 mA h g^(−1) at 1 A g^(−1)),a superb rate capability(83.6 mA h g^(−1) at 100 A g^(−1))and a splendid electrochemical stability(92%capacity retention after 5000 cycles at 10 A g^(−1)).Furthermore,a novel HSC device assembled with Co_(3)(HPO_(4))_(2)(OH)_(2) as the cathode,porous carbon(PC)as the anode showed a high energy density of 44.6 W h kg^(−1) and a remarkable power density of 33.75 kW kg^(−1),along with an exceptional cyclic performance(91.8%capacity retention after 10,000 cycles at 3 A g^(−1)).This study not only develops a novel type of high-performance battery-type cathode material,but also provides a new idea for the industrial application of RP.展开更多
文摘The oxidation behavior of Al2O3-30%TiCN-0.2%Y2O3 composite and its effect on high temperature bending strength was studied. The result indicates that the mass gain during static oxidation of the material under normal atmosphere follows the parabolic law. Oxide increases with increasing temperature and prolonging time. It has good oxidation resistance. The product of oxidation of the material is TiO2. Therefore, the volume of the material expands. The oxide film is destroyed because residual stress inside the oxide film is released. Proper oxidation is beneficial to the improvement of bending strength of Al2O3-30%TiCN-0.2%Y2O3 composite. The strength increase is up to 4.5%.
基金by the major state basic research program(No.G1999043809)the National Natural Science Foundation of China(No.40076003)the the Excellent Young Teachers Program of Ministry of Education,P.R.China(M.[2001]39)
文摘By the use of the 3/2 power law presented by Toba combined with the significant wave energy balance equation for wind wave, wind wave growth at a limited fetch is analytically investigated. The new wind wave growth relations (WWGRs) are analytically derived with sheltering coefficient and wind drag coefficient as parameters. The geometrical average of observational values of sheltering coefficient and the arithmetic average of observational values of wind drag coefficient are applied to determine the new WWGRs. Comparisons with existing empirical WWGRs are made.
文摘Wind input parameterizations proposed by Jeffreys, Sverdrup and Munk, and Plant are analyzed. It is found by analogy that the similarity of integrals of the three wind input parameterizations exists. Wave breaking dissipation parameterizations proposed by Tsikunov, Hasselmann, and Phillips are also analyzed. Likewise it is found by analogy that the similarity of integrals of the three dissipation parameterizations exists. The similarities of wind input and dissipation are applied to the investigation of the fetch-limited growth of wind waves, together with the 3/2 power law presented by Toba. Some semi-empirical formulas concerning the growth of wave height and period with fetch are presented. The results from the formulas are in good agreement with previous field observations.
基金financially supported by the National Natural Science Foundation of China(21601057)Hunan Provincial Natural Science Foundation(2021JJ30216)。
文摘Red phosphorus(RP)is beneficial to industrialization due to its rich resources,chemical stability and environmental friendliness.However,the low electronic conductivity and large volume expansion limit its application for energy storage.Herein,we first used RP to prepare a novel bouquet-like Co_(3)(HPO_(4))_(2)(OH)_(2) by the hydrothermal approach as cathode materials for hybrid supercapacitors(HSC),which delivered a large specific capacity(119.2 mA h g^(−1) at 1 A g^(−1)),a superb rate capability(83.6 mA h g^(−1) at 100 A g^(−1))and a splendid electrochemical stability(92%capacity retention after 5000 cycles at 10 A g^(−1)).Furthermore,a novel HSC device assembled with Co_(3)(HPO_(4))_(2)(OH)_(2) as the cathode,porous carbon(PC)as the anode showed a high energy density of 44.6 W h kg^(−1) and a remarkable power density of 33.75 kW kg^(−1),along with an exceptional cyclic performance(91.8%capacity retention after 10,000 cycles at 3 A g^(−1)).This study not only develops a novel type of high-performance battery-type cathode material,but also provides a new idea for the industrial application of RP.
