Anatase Ti0_(2) nanosheet-based hierarchical spheres(HSs)with nearly 100%exposed{001}facets were synthesized via a facile solvothermal process.Using these hierarchical spheres as a scattering layer on nanocrystaline T...Anatase Ti0_(2) nanosheet-based hierarchical spheres(HSs)with nearly 100%exposed{001}facets were synthesized via a facile solvothermal process.Using these hierarchical spheres as a scattering layer on nanocrystaline TiO_(2)film,hi-layered dye-sensitized solar cells(DSSCs)have been fabricated by electrophoresis deposition method,which well preserved the fragile hierarchical structure.Owing to the superior dye adsorption and light scattering effect of HSs,an overall energy conversion efficiency of 7.38%is achieved,which is 26%higher than that of nanoparticle-based photoanode.展开更多
Density waves in 3D spiral galaxies are studied.In order to eliminate the forbidden region near the corotation in the grand-design galaxies,we assume that the perturbation satisfies the stable condition Q(r)>1 over...Density waves in 3D spiral galaxies are studied.In order to eliminate the forbidden region near the corotation in the grand-design galaxies,we assume that the perturbation satisfies the stable condition Q(r)>1 over all the disk except that at the corotation.Then,a new method is put forward here to determine some basic parameters of spiral galaxies.We apply it to our Galaxy,and the results are in good agreement with the previous results.展开更多
A new method is presented to determine the thickness of spiral galaxies.Based on the rigorous solution of the Poisson equation for logarithmic density disturbance in three-dimensional spiral galaxies,we have derived a...A new method is presented to determine the thickness of spiral galaxies.Based on the rigorous solution of the Poisson equation for logarithmic density disturbance in three-dimensional spiral galaxies,we have derived an accurate dispersion relation for the stellar and gaseous disk with a finite thickness.From this relation,a new method is put forward here for determining the thickness of galaxies.We apply this way to M31 and get the thickness of about 0.7kpc,which is in good agreement with the previous results.展开更多
文摘Anatase Ti0_(2) nanosheet-based hierarchical spheres(HSs)with nearly 100%exposed{001}facets were synthesized via a facile solvothermal process.Using these hierarchical spheres as a scattering layer on nanocrystaline TiO_(2)film,hi-layered dye-sensitized solar cells(DSSCs)have been fabricated by electrophoresis deposition method,which well preserved the fragile hierarchical structure.Owing to the superior dye adsorption and light scattering effect of HSs,an overall energy conversion efficiency of 7.38%is achieved,which is 26%higher than that of nanoparticle-based photoanode.
基金Supported in part by the National Natural Science Foundation of China under Grant No.19873005the Director Foundation of National Education Ministry(9528424)the National Climbing Project on Fundamental Researches.
文摘Density waves in 3D spiral galaxies are studied.In order to eliminate the forbidden region near the corotation in the grand-design galaxies,we assume that the perturbation satisfies the stable condition Q(r)>1 over all the disk except that at the corotation.Then,a new method is put forward here to determine some basic parameters of spiral galaxies.We apply it to our Galaxy,and the results are in good agreement with the previous results.
基金Supported in part by the National Natural Science Foundation of China under Grant No.19873005the Director Foundation of National Education Ministry(9528424)the National Climbing Project on Fundamental Researches.
文摘A new method is presented to determine the thickness of spiral galaxies.Based on the rigorous solution of the Poisson equation for logarithmic density disturbance in three-dimensional spiral galaxies,we have derived an accurate dispersion relation for the stellar and gaseous disk with a finite thickness.From this relation,a new method is put forward here for determining the thickness of galaxies.We apply this way to M31 and get the thickness of about 0.7kpc,which is in good agreement with the previous results.