We investigate the role and behaviour of dust grains in C-type MHD shock waves in weakly ionized, dense molecular clouds. The structure of C-type shocks in molecular clouds are largely determined by the coupling of the charged species and the magnetic fields in the pre-shock gas. In weakly ionized clouds, charged dust grains enhance the energy and momentum transfer between the magnetic field an...

Grain size is an important control on mantle viscosity and permeability, but is difficult or impossible to measure in situ. We construct a two-dimensional, single phase model for the steady state mean grain size beneath a mid-ocean ridge. The mantle rheology is modeled as a composite of diffusion creep, dislocation creep, dislocation accommodated grain boundary sliding, and a plastic stress lim...

To uncover the genetics of rice grain weight, we constructed an RIL population derived from a cross between a large grain accession M201 and a small size variety JY293. Specific Locus Amplified Fragment Sequencing (SLAF-Seq) technology was used to genotype two bulked DNA pools made from individual DNA of the heaviest 30 lines and the lightest 30 lines according to the 1000 grain weight (TGW). B...

In this paper, the microstructure, the room-temperature and high-temperature tensile mechanical properties of monolithic TA15 alloy and TiB whisker-reinforced TA15 titanium matrix composites (TiBw/TA15) fabricated by vacuum hot-pressing sintering were investigated. The microstructure results showed that there were no obvious differences in the microstructure between monolithic TA15 alloy and Ti...

The pinning effect of small incoherent particles on grain growth in two-dimensional polycrystalline systems has been simulated using a phase field model. Simulations were performed for different sizes and area fractions of the second-phase particles and for two types of initial microstructure and different initial grain sizes. The grain size distribution and the number of particles located at g...

A field experiment was conducted during 2001-2003 to evaluate the effect of water stress on the yield and yield components of four rice cultivars commonly grown in Mazandaran province, Iran. In northern Iran irrigated lowland rice usually experiences water deficit during the growing season include of land preparation time, planting, tillering stage, flowering and grain filing period. Recently d...

Two silver samples, coarse grained (c-Ag, grain size 300730 nm) and nanocrystalline (n-Ag, grain size 5576 nm), are compressed in a diamond anvil cell in separate experiments. The pressure is increased in steps of 3 GPa and the diffraction pattern recorded at each pressure. The grain size and compressive strength are determined from the analysis of the diffraction line-widths. The grain size of...

We study a 3D bicrystal containing an axially symmetric shrinking grain which is initially a spherical segment attached along a circular groove root to the flat exterior surface of the second grain. Following Mullins [1]-[3], a time dependent problem is formulated for the coupled motion of the grain boundary, the groove root, and the external surface. Numerical solutions calculated using an imp...

The magnetic permeabiility and the thickness of the socalled %on"magnetic grain boundary were studied for a MgMnZn-femte with composition M~,J~,&ln,lFe,,,03,m For the mono-domain situation the grain size dependence of the effective initial permeability is well described by the nonmagnetic grain boundary model. A gradual increase of permeability with grain size around the transition from monoto ...

The purpose of this paper is to describe the five-parameter grain boundary character distribution (GBCD) of polycrystalline silicon and compare it to distributions measured in metals and ceramics. The GBCD was determined from the stereological analysis of electron backscatter diffraction maps. The distribution of grain boundary disorientations is non-random and has peaks at 36", 39", 45", 51", ...