Lifting-line model is developed for a propeller of large aspect ratio inblade-attached noninertial system. In the analysis of the method of matched asymptoticexpansions, a fictitious velocity potential is introduced. ...Lifting-line model is developed for a propeller of large aspect ratio inblade-attached noninertial system. In the analysis of the method of matched asymptoticexpansions, a fictitious velocity potential is introduced. Control equation, boundarycondition and Bernoulli equation are derived in blade- attached system. The analysis ofthe matched asymptotic expansions shows that if the advance ratio of propeller is notvery small, lifting-line theory is still valid in blade-attached noninertial system for propeller.展开更多
Different precursors were prepared via a simple low heat solid state reaction(LHSSR) upon changing the ligands. The ZnO photoanode films were obtained by the doctor blade technique, and their composition, thermal de...Different precursors were prepared via a simple low heat solid state reaction(LHSSR) upon changing the ligands. The ZnO photoanode films were obtained by the doctor blade technique, and their composition, thermal decomposition process and morphologies were identified by means of X-ray diffraction(XRD), thermal gravimetric analysis-differential thermal analysis(TGA-SDTA) and scanning electron microscope(SEM). The results show that the morphologies of ZnO photoanodes are irregular block, regular lamellar and irregular sheet-cluster, and the multistage structure can be found in all the photoanodes. Furthermore, there exists a genetic effect of morphology between the precursors and the corresponding photoanodes. The optimum power conversion efficiency of the sheet-cluster ZnO photoanode was 3.12% with the short circuit current density(dsc) being 11.23 mA/cm2. The multistage sheet-cluster structure could result in the increase of the scattering of the incident light and provide a rapid electronic transmission channel to reduce the risk of electronic recombination. A beneficial enlightenment was obtained to simplify the process and the photoanode films with various morphologies can be prepared with lower price in the further research.展开更多
文摘Lifting-line model is developed for a propeller of large aspect ratio inblade-attached noninertial system. In the analysis of the method of matched asymptoticexpansions, a fictitious velocity potential is introduced. Control equation, boundarycondition and Bernoulli equation are derived in blade- attached system. The analysis ofthe matched asymptotic expansions shows that if the advance ratio of propeller is notvery small, lifting-line theory is still valid in blade-attached noninertial system for propeller.
文摘Different precursors were prepared via a simple low heat solid state reaction(LHSSR) upon changing the ligands. The ZnO photoanode films were obtained by the doctor blade technique, and their composition, thermal decomposition process and morphologies were identified by means of X-ray diffraction(XRD), thermal gravimetric analysis-differential thermal analysis(TGA-SDTA) and scanning electron microscope(SEM). The results show that the morphologies of ZnO photoanodes are irregular block, regular lamellar and irregular sheet-cluster, and the multistage structure can be found in all the photoanodes. Furthermore, there exists a genetic effect of morphology between the precursors and the corresponding photoanodes. The optimum power conversion efficiency of the sheet-cluster ZnO photoanode was 3.12% with the short circuit current density(dsc) being 11.23 mA/cm2. The multistage sheet-cluster structure could result in the increase of the scattering of the incident light and provide a rapid electronic transmission channel to reduce the risk of electronic recombination. A beneficial enlightenment was obtained to simplify the process and the photoanode films with various morphologies can be prepared with lower price in the further research.