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Although the HVPE-GaN seed crystal is almost opaque due to a lot of included grain boundaries, the transparency of the LPE crystal (a result of the LPE growth that filled in the boundaries) is sufficient to be able to discern the characters through the crystal, as shown in Figure 4.
We estimated the number of dislocations included in the crystal from the etching treatment in the 500 ºC NaOH melt.
In the circle in Fig. 6b, a light scattering due to low-angle grain boundaries that should be derived from the coalescence of the facets can be seen just under the dislocation line.
Although bent dislocations may move outside the sample, TEM observation indicates that the number of dislocations should be drastically reduced.
Thereafter, the number of facets decreased as thickness increased and a (0001) face started to develop.

In addition to the solid and liquid phase, a phase related to the interdendritic liquid which is enclosed within a dendritic grain is introduced [11].
The distinction between extradendritic and interdendritic liquid is based on the notion of an envelope, which connects tips of a dendritic grain [12].
The influence of a magnetic field on fluid flow is characterized by several non-dimensional parameters which are the skin layer δ normalized by the pool radius R, the interaction parameter � and the magnetic Taylor number mTa .
Dimensionless numbers and parameters applied in simulation
Time of formation of a sole lateral "tree branch" is about s30 and during this period a number of vortices dissipate in a mushy zone.

By using radioactive isotopes of Co-57 and Am-241, the energy calibration formula was calculated as follows: En = 0.059066×CH + 0.37067 [KeV], (1) where CH is a channel number of MCA.
Integrated intensity becomes so high that there are many crystal grains which satisfies X-ray diffraction conditions.
Acknowledgement The synchrotron radiation experiments were performed at the BL28B2 of SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal Number 2012B125).
And this study was supported by JSPS KAKENHI Grant Number 24560083.
Weertman, Dislocations, grain size and planar faults in nanostructured copper determined by high resolution X-ray diffraction and a new procedure of peak profile analysis, Acta.

The grain size of spherical CaCO3 became bigger, surface became smoother, and particle dispersion became better with the increase of calcium ion concentration.
The content of vaterite increased and particle grain size changed a little with the increase of pH.
The application of vaterite particles is determined by a great number of strictly defined parameters, such as large surface area, good dispersibility, small density, good solubility and so on[1-2].

In this paper, aluminum alloy 7075 is used as the raw material to study the tensile strength of the welding interface and the development of welding seam and grains by using local compression test.
The cut specimen is milled by waterproof abrasive paper of different numbers (#_240, 400, 600, 800, 1200, 1500, 2000, 2400, 4000), and then finished by 0.5μm Al2O3 powder aqueous solution.
On the lower billet, different grains have obvious black lines in different directions, it may because of the new plane direction resulted from the heating pressing process.
The grains in main body specimen, as shown in Fig. 14(a) and (b), are round, whereas long and narrow grain shape is formed on flash part specimen due to material shear flow.
The metallurgical structure observed through OM: (a) upper specimen of main body; (b) lower specimen of main body; (c) flash part has long grains and almost no seam.

Analytical surveillance programmes by food controlling agencies are required to control aflatoxin contamination of food grains and human exposure.
This method is recommended for detection and quantification of the less toxic aflatoxin B2, which is presented in grains.
Currently, the easy availability of ELISA kits has paved the way for analysis of large number of samples simultaneously.
This technique has been successfully applied for analyzing aflatoxins in grains and peanuts [51].
Pascale, Detection methods for mycotoxins in cereal grains and cereal p roducts, Matica Srpska Proceedings for Natural Sciences 117 (2009) 15-25

Depending on the size of the volumes in which they manifest (appears an heterogeneity of deformation) are defined the following categories of residual stresses [3, 10, 12]: a) macrostresses: - first order residual stresses (macroscopic) (), which causes deformations and develops in the deformed piece at a larger scale than the grain size of the material or a significant volume element (millimeters), they result from the balance of internal forces and correspond to an average value of all the material; b) microstresses: - second-order residual stresses (microscopic or intergranular) () acting at the grain scale (micrometer), they are almost always at polycrystalline materials because the elastic and thermal properties of neighboring grains are different; their value is a stress variation of every grain around the average value, represented by the () stress; () stresses are referred to as homogeneous microstresses
- third-order residual stresses or ultramicroscopic (), acting on the level of atoms, due to the presence of dislocations or other crystal lattice defects (at a scale on the order of a few tens of nanometers), they are found in materials with multiphasic microstructure, being generated by the phasic transformations; their value fluctuates around the mean value of the stresses of a grain (); stresses can be called heterogeneous microstresses.
Recent specialized literature [14], suggests a concept of residual stress management and a number of engineering tools to analyze the major aspects of residual stresses.

The accumulation surface④ is level and its friction coefficient is 0.4. ① ② ③ ④ ①sliding surface ②mounding trough ③motion surface④accumulation surface Fig.2 Numerical Experimentation Model 2.2 Generate sample and set parameter Comprehensive calculation efficiency, the grain composition of physical model and similar degree and particle size distribution, the grain size will be enlarged in order to reduce the grain number and computing workload, and improve the calculation efficiency, eventually, 501 particles are generated, which diameter of its size range is 0.1-0.3 m.
Monitoring results of average contact force and average unbalance force between particles and monitoring results of y direction action force the change of the retaining wall of fill the tank (figure 3, 4) showed that average contact force between particles stable, unbalance force tend to zero, accumulation grains get to stable equilibrium state.
[10] LU Xiao-bing, ZHANG Xu-hui ，Numerical simulation of clastic grain flow along a slope[J], Rock and Mechanics，2009，Vol.30 Supp.2：524-527( in Chineses) [11] LIU Jian-bao, WANG Nai-ang, etc, Influencing Factors of Respose Angle of Sand Dunes: an experiment[J], JOURNAL OF DESERT RESEARC, 2010 ,Vol.30 No.4,758-762( in Chineses) [12] Jiang Peng,Yang Shubi, EXPERIMENT STUDY ON RHEOLOGIC BEHAVIOR AND LONG TERM STRENGTH OF GRAVEL IN CHENGDU AREA[J], Journal of Geological Hazards and Environment Preservation, 1998,Vol.9 No.1,38-42( in Chineses)

Sample number 1 was the sample before nitrocarburization.
Samples number 2 and 3 were samples after nitrocarburization at a temperature of 400oC for 5 and 6 hours consecutively.
This means that in a change of nitrocarburization time from 5 hours to 6 hours, the number of nitrogen and carbon atoms that have diffused into the local bolt material did not increase much.
Figures 3-7 shows the matrixes of ferrite, pearlite, austenite, and grain boundaries.
Dutka, Journal of Super-hard Materials, 1063-4576, Vol. 30, Number 5, 2008

The average grain size, found using the linear intercept method, was 3.6 mm.
Hysteresis loops for selected numbers of cycles were recorded in disk memory.
Results and discussion The stress amplitude σa as a function of the number of cycles N obtained for both treated and untreated specimens cycled at 800 °C is shown in Fig. 1.
Fig. 2a shows the stress amplitude σa at half life vs. the number of cycles to fracture Nf in the bilogarithmic representation.
Fatigue life curves in the representation of the plastic strain amplitude εap at half life vs. the number of cycles to fracture Nf are shown in Fig. 2b.