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The indices of the reflecting crystal planes are indicated on dark-field images, as well as the numbers are indicated on SAED.
In the SEM-image of sample 1, a large number of pores is clearly seen, in spite of using the nanopowder Cu-Sn.
This unsatisfied structure and a low sample density (ρ=62%), allows us to conclude that the obtained solid sample under such conditions is not of a sufficient quality because of a significant number of pores, the presence of which can be easily explained by the low sintering temperature.
More than 50 percent of the sample consists of gray grains, which most likely are intermetallic Cu-Sn.
However, there are seen the impregnations of material (white) that fill the space between the grain boundaries, reducing the number of pores.

Number of tools were produced for the injection moulding applications, and some of them in the production of the tools for zinc alloy (casting temperature 420-430 degrees Celsius, pressure 300 bars) and aluminium die casting (casting temperature 690 degrees Celsius, pressure 400 bars).
The thickness of the first and the next layer is equal to the grain size of the powder (accuracy of the part ± 50 microns, minimum thickness of the wall 0.6 mm) For DMLS applications three different powders (developed by Electro Optical Systems Finland Finland) are recently used: DM 20 (grain size 20 microns) is based on bronze (for tooling inserts for injection molding up to 10.000 pieces and for functional prototypes), and DS 20 (grain size 20 microns) is based on steel (for injection molding tooling inserts up to 100.000 pieces, aluminum casting up to 1.000 castings and for functional metal prototypes).
Material DS H20 (grain size 20 microns) is the latest on steel based material which offers the highest strength, hardness, wear resistance and surface density of all available materials.
The sintered steel structure is dense, fine-grained material showing very fine dendrite spacing.

From these reasons in a number of cases Gd and Y elements are used replaceable because they play the same role in crystalline structure and strongly modify magnetic interactions.
Note, that higher amount of Y atoms is connected with a grain growing of the nanocrystalline phase.
Indeed, in the case of the Y15 sample the mean diameters of Fe2B, Fe2Y and BFe14Y2 grains were found to be about 60 nm.
For the sample denoted as Y30 the mean grain size was determined as 57 nm.
 The addition of 4.8 at. % of yttrium causes formation of iron nanocrystallities with mean grain diameter of 64 nm.

Coolant with anionic surfactant is effective in reducing the friction between diamond grains and quartz grains in stone [4].
The absorbed lubricating films have been found between the diamond and quartz grains.
observation and the measurement of surface roughness have proved that the small breakages of granite are caused more frequently using coolant with surfactants than using water [7]. 600 700 800 900 10000 10-2 10-1 1 Surfactant concentration (%) Surface microhardness HV0.02 Cationic Non-ironic Anionic Water -80 -40 0 40 800 10-3 10-2 10-1 1 Cationic Non-ionic Anionic Surfactant concentration (%) Zeta potential (mv) Fig.5 Surface zeta potential of granite Fig.6 Surface micro-hardness of granite ground by different surfactants [7] with several surfactants by diamond disk 0 1.0 2.0 3.0 4.0 5.0 10-3 10-2 10-1 1 Cationic Non-ionic Anionic Water Surfactant Concentration (%) Material removal rate (mm 3 /s) 0 0.5 1.0 1.5 2.0 600# 1000# 1500# 2000# Water Cationic(0.02%) Diamond grit mesh Material removal (mm3/s) rate Fig.7 Material removal rates of different Fig.8 Effects of diamond grain
This is because the number of cutting edges increases, the cutting forces acting on each individual grit decrease.
The granite with higher quartz content and a larger grain size normally shows fewer initial defects and higher hardness.

The test pieces chemically cleaned with acetone just before welding and rigid clamped in the fixture by a number of fingers which prevent any movement during friction stir welding operation.
This can be attributed to the temperature increasing with increasing rotation speed and became close to melting temperature of Al at high rotation speeds, and perhaps liquation of grain boundary occurred.
This seems to cause grains coarsening instead of the more grains refining expected.
This behavior is realistic because lowering welding speed may introduce more heat input to the weld joint and time available for dynamic grain refining of weld metal.
But more decrease in welding speed may introduce much higher heat input to weld joint enough to rise peak temperature again near melting temperature and generate coarser grains instead of finer one Fig. 5.

Polycrystalline metals, ceramics and natural rocks are aggregates of crystallite grains, characterised by structure, size and crystal lattice orientation distributions.
Due to the inhomogeneous nature of lattice orientations and anisotropic mechanical properties, local grain level stresses invariably arise when a polycrystalline material is deformed [1, 2].
The evolution of these two families of grains has been determined by studying a specific azimuthal angular section of 15◦ for the perpendicular direction) on the detector [3].
A fit of individual planes to a pseudo-Voigt profile function was used in order to study the strain partitioning between subsets of grains having specific {hkl} plane-normals oriented parallel and perpendicular to the loading direction [3].
Discussion and summary The errors in the calculation of the phase specific elastic constants could come from a number of sources.

For austenitic weld metal with a columnar grain structure, a common assumption is that the material is transversely isotropic.
The experiment exhibits that the type of grain structure about the austenitic weld is columnar grain structure [4].
It can be mathematically expressed as: (8) Where and are the Young modulus obtained by experiments and predicted by regression formulas respectively; and are the mean values of and , respectively; N is the number of the statistical samples.
Because the type of grain structure about the cladding stainless steel layer shows columnar grain structure, the each layer of the stainless steel caldded layers can be approximately simplified as the transversely isotropic material.

Thus it could also change crystal direction of the grain, refine microstructure, lower impurity, decrease segregation and improve the overall performance of welding joint [1].
These achieved the purpose of refining grain, inhibiting blow holes, reducing spatter, reducing cracks.
This promotes the bulky columnar crystal and dendrites into small cubic and refines grain [25].
Results of fatigue life testing are plotted as curves in terms of the maximum load versus number of cycles to failure, as shown in Fig. 6.
[24] Hellawell A: Grain evolution in conventional castings [A].

The electromagnetic radiation emitted by an assembly of nano-entities (molecules, dots, grains) by way of the feedback effect establishes their coherence thus greatly reducing the duration and enhancing the intensity of the deexcitation pulse.
Then the dimensionless dipolar field in the -th site is , , (2) where is the radius-vector connecting the particles with the numbers and ; are dimensionless vectors of interparticle distances, is a mean interparticle distance.
Figures 2с, 2d, and 2e then illustrate the speed of relaxation for these two orientations for different number of the layers.

In the Czech Republic there is a number of composting plants with poor sales of compost they produce, in spite of the fact that they offer it for one third of the price if compared to the value of the nutrients contained.
Grain size composition Fig. 1 shows the result of grain size analysis – mean value of grain size (d050) for the studied composts.
In all the composts where wood chips were added, grain size is bigger than 3 mm.
Fig. 1 Mean value of grain size in composts Conclusions With respect to energy utilization, 10 composts produced in composting plants in the Moravosilesian Region were studied.