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The high crystalline quality is characterized by the absence of secondary polytype inclusions and the absence double position grain boundaries.
A number of approaches have been followed in the past with the goal to grow high quality cubic SiC for the application in electronic devices.
The suppression of double position grain boundaries remains very critical.
In this work a number of positions and sizes of the tantalum foil have been tested.
The material is free of double position grain boundaries and exhibits no secondary polytype inclusions.

It is now evident that the driving force for this unusual phenomenon is the softening associated with the replacement of particular work-hardened austenite grains by softer, undeformed ferrite grains [3].
Dependence of the volume fraction of ferrite on pass number for the C-Mn steel.
The phase proportions increase with pass number to a maximum of about 35% and decrease with the length of the interpass interval.
Dependence of the volume fraction of ferrite on pass number for the X70 steel.
It should be noted that transformation does not occur simultaneously throughout the material, as the grains that are appropriately oriented crystallographically transform before the others (i.e. high m-value grains).

The results show that before ageing, a large number of fine γ precipitates with DO22 type structure are distributed on the matrix.
Then the increased DP at grain boundaries leads to the decline of strength in the material.
A great number of fine precipitates were observed in the matrix, as marked by SADP, these fine precipitates are ordered phase with D022 type structure (Fig. 2(b)).
As observed in Fig. 2(a), Fig. 3(b-f), the DP appear at grain boundaries, under 400 ℃ more DP exhibited at 1400 min than at 360 min.
According to Matthiessen’ s rule [16], the electrical resistivity is related to the precipitates, solute atoms, dislocations, vacancies and grain boundaries.

The overall rate of reaction of VM can be expressed as: (3) (3) The GM model or unreacted core model was proposed by Szekely and Evans[4].The model assumes that a solid pellet is consisted with a number of small particle or grain[5].
In this model, the pore surrounds the grain.
The reaction occurs at the surface of the grain.
Therefore, in order to react with grain, the gasifying agent must firstly defuse through the pore to reach the surface of the grain.
A product layer will be form on the surface of the grain throughout the time.

This feature makes the program effective for a large number of steel grades with a wide range of chemical composition variations.
Fig. 4 shows predicted variation in austenite grain size and retained strain over the strip width of Grade #1 steel with time of rolling.
Predicted variation in austenite grain size (a) and retained strain (b) distributions over the strip width in Grade #1 steel with time of rolling.
This model was calibrated using a mechanical properties data base for a number of practically important steels hot rolled on mill 2000 under different rolling regimes.
The model STAN 2000 has greatly contributed to the development of new technologies for production of pipe steels, high strength steels for mechanical engineering and shipbuilding, as well as a number of structural steels.

The density of SSB is represented by the number of viable seeds per unit area in the soil.
Results and Analysis The species composition and density of SSB The total germinated seedlings are 3274 grains.Urban districts are 1432 grains, belonging to 12 families, 14 genera and 14 kinds;suburban districts are 1157 grains, belonging to 19 families, 23 genera 36 kinds; outer suburbs are 685 grains, belonging to 26 families and 39 genera 42 kinds.
Table 3 The similarity between SSB and ground vegetation in different regions Regions a b w Sorensen Index Urban districts 14 35 9 0.367 Suburban districts 23 61 14 0.333 Outer suburbs 42 63 13 0.248 a-the specie number in SSB b-the specie number of ground vegetation c-the specie number in common Community structure of SSB As gene reservoir of the ground vegetation, SSB can carry important information of community succession[8].
The closer to the urban districts, the larger number of herbs.
As an important reference for vegetation restoration，the numbers of woody plants are very important.In suburban districts, the numbers of woody plants are more than 10 times than the other two regions.The differences in number of Lianas are significant,the number are 6, 21, 44.

Meanwhile, the SAPS-YSZ coating exhibited a bimodal distribution with small grains (30-50nm) and large grains (60-110nm), the latter was the main microstructure of the coating.
The measured values for particle velocity and surface temperature in operating condition were the average values of detected particles (the number of particles were approximately 2000).
As shown in Fig.4a and Fig.4b, the as-sprayed coating was mainly composed of unmelted feedstock particles with grain size ranging from 30 to 50nm and crystals formed from the melt with grain size ranging from 60 to 110nm.
In addition, the grain size of the latter was larger than that of the former.
Fig.4 TEM micrographs of as-sprayed YSZ coating; (a) unmelted particles with grain size ranging from 30 to 50nm; (b) crystals formed from the melt with grain size ranging from 70 to110nm; (c) HRTEM micrograph of grain boundary.

Objective: To study whether the veneering technique will have an impact on zirconia grain and the bonding type and relationship on interface between zirconia and veneer porcelain.
Grated to the final thickness of 1 mm, veneer porcelain were grated and polished orderly (the final grain of polish paste was 1µm).
The interface was grated and polished (the grain of final polish paste was 1µm), then it was acid-etched with 9.5%HF glue for 15s, 30s and 60s separately.
With etching time extending, a large number of material loosed in the veneering side of 4 types porcelain and corrosional hit deepened, enlarged.
In the TEM observation for interface between KAVO zirconia and VINTAGE dentin porcelain, this study discovered an interface of about 200nm between zirconia grain and glass.

Introduction Severe plastic deformation（SPD）methods have been developed in order to create bulk ultrafine-grained materials on account of severe plastic deformation by mechanical methods and materials that there is nano-internal organization and no holes, density, and material purity can be refinemented by its strong grain refining capacity [1].
Three-dimensional modeling, built by Pro/E Wildfire4.0 software firstly, is imported into Deform-3D software. and modeling parameters as follow: Material 1100Al from software materials library of Deform-3D is selected,and sample geometry is 15mm×15mm×70mm; Helix angle of spiral channel =90°and length of spiral channel L=30mm, and spiral groove is 10mm×10mm×30mm .The die and punch are assumed to be non-occurrence of deformation and heat conduction and rigid solid type; Four-node isoparametric tetrahedral elements and adaptive mesh re-classified technical are adopted to automatically divide into grids and the number of grid cells is set to 40000.
Structure and properties of ultrafine-grained materials produced by severe plastic deformation[J].
Trend of Ultrafine grained steel[J].
[6] Valiev RZ, Estrin Y, Horita Z, Langdon TG, Zehetbauer MJ, Zhu YT Producing Bulk Ultrafine-grained Materials by Severe Plastic Deformation[J].

Asymmetrical distributions show bleached and unbleached grains.
HF was used to remove most of the feldspars and to etch the surface of quartz grains.
After that few grains (<1 g) of feldspar contaminated quartz subsamples remained.
A different number of aliquots were measured for each sample.
However, further research on a higher number of lime mortar samples with different origin and ages is needed to study the problems found in this first insight.