Vertically aligned ZnO nanowires have been synthesized by a hydrothermal method. After being irradiated by a short laser pulse, the tips of the as-synthesized ZnO nanowires can be tailored into a spherical shape. Transmission electron microscopy revealed that the spherical tip is a single-crystalline piece connected to the body of the ZnO nanowire, and that the center of the sphere is hollow. T...

We present a novel method for estimating 3-D positions of near light sources by using highlights on the outside and inside of a single clear hollow sphere. Conventionally, the positions of near light sources have been estimated by using observed highlights on multiple reference objects, e.g. mirror balls.

In this paper, the general solution of steady-state two-dimensional non-axisymmetric mechanical and thermal stresses and mechanical displacements of a hollow thick cylinder made of fluid-saturated functionally graded porous material (FGPM) is presented. The general form of thermal and mechanical boundary conditions is considered on the inside and outside surfaces. A direct method is used to sol...

We report the peculiar behavior of the oblique impacts of a single sphere on stationary like spheres arranged in a tetrahedral array. We compare the resulting kinematic coefficient of normal restitution to that in impacts on a single sphere attached to a thick plate and in binary impacts. The results provide detailed insight into the generation of ejecta in the saltation process.

The formation of a hollow cellular sphere is often one of the first steps of multicellular embryonic development. In the case of Hydra, the sphere breaks its initial symmetry to form a foot-head axis. During this process a gene, ks1, is increasingly expressed in localized cell domains whose size distribution becomes scale-free at the axis-locking moment. We show that a physical model based sole...

In this paper, we investigate the vortex nucleation on a thin superconducting hollow sphere. The problem is studied using a simplified system of Ginzburg–Landau equations. We present numerical algorithms which preserve the discrete gauge invariance for both time dependent and time independent simulations. The spatial discretization is based on a spherical centroidal Voronoi tessellation which o...

Cu/Cu2O nano-heterostructure hollow spheres with a submicron diameter (200-500 nm) were prepared by a microwave-assisted hydrothermal method using Cu(OAc)2·H2O, PVP and ascorbic acid solution as the precursors. The morphology of the products could evolve with the hydrothermal time from solid spheres to thick-shell hollow spheres, then to thin-shell hollow spheres, and finally to nanoparticles. ...

Measurements are presented of the phase function, P11, and asymmetry parameter, g, of five ice clouds created in a laboratory cloud chamber. At 7 1C, two clouds were created: one comprised entirely of solid columns, and one comprised entirely of hollow columns. Similarly at 15 1C, two clouds were created: one consisting of solid plates and one consisting of hollow plates. At 30 1C, only hollow ...