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The structure of palladium grains were measured in a H2/N2 gas mixture atmosphere containing H2 in the concentration range 0-4%.
Absorption of hydrogen into palladium is a two-step process involving dissociative chemisorption on the Pd surface and subsequent diffusion of hydrogen atoms into the bulk of metal nano-grains.
In the last years, it was found that palladium in the form of nano-grains caused an improvement of the hydrogen sensing properties.
LABE detector shows a contrast composition of analyzed material regarding Z (atomic number).
In S1 sample (Fig. 1a, b) Pd nano-grains are located at grain boundaries of the substrate forming conductive paths, in contrast to S2 sample (Fig. 1c, d), where Pd nano-grains are spread over the entire surface of substrate.

The density of the soil seed bank are indicated by the number of viable seed in per unit area[6].All datas were processed and analyzed by PASW Statistics 18.0 and Excel software.
Results and Analysis The density and composition of SSB After the germation test, all the germinated seedlings are 1364 grains, containing 21 genera and 12 families and 25 species, Compositae have the richest species.
Among all the germinated seeds, the numbers of Glycine soja and Setaria viridis are huge, while the numbers of others species are small.
As most of the lands are surrounded by the water,large numbers of plant seeds fall into the water, water transportation sends this seeds to long-range places.
The results show that the species are not abundant,only belonging to 12 families, 21 genera and 25 kinds.But its density is very considerable, detected viable seeds reach to 1364 grains,the density of soil seed bank can reach to7.27×105grains/m2.That means there are potentials for regeneration by using SSB.

A number of particles near the surfaces of the cell wall appear to be slug trapped during casting.
It may suggest that the number of nuclei for solidification is not sufficient for such liquid thin film of several tens of micrometers in thickness during the solidification/foaming process of the foams.
It seems most likely that stress singularity at free edges of grain boundaries (i.e. intersections between surface and grain boundaries) can reduce apparent stress necessary in case of grain boundary fracture.
Number of cracks observed is about 50 % larger in the dynamic loading than that of the quasi-static loading.
Since grain boundary is not shown in these images because the liquid metal wetting technique is fundamentally a destructive inspection due to the liquid metal embrittlement, only large numbers of micro-pores and particles are seen in the figure.

As more layers are added, the refined grains become nuclei to form elongated and thin columnar grains.
According to Shuai et al. [14], average grain size increases on decreasing laser scanning speed.
The grain size becomes larger when the scanning speed is further decreased.
Moreover, according to Akinlabi and Akinlabi [15] and Fatoba et al. [16], increase in number of scan changes to type of heat treatment and produces strain hardening in material causing the grain sizes to be reduced as laser scans increases.
Effect of Grain Size Deformation on Laser Processed Sheet Steel Under High Temperature.

Angularity refers to the number and size of corners.
The grain is characterized by a smooth and polished surface.
The value of fractal dimension DS increases from 2.662 for the smoothest grain, to 2.879 for the grain with the most variable and complex microtexture.
Mahaney, Atlas of sand grain surface textures and applications, Oxford Univ.
Woronko, Micromorphology of quartz grains as a tool in the reconstruction of periglacial environment, in: P.

(1) where Γ is the Gibbs-Thomson coefficient, R is the dendrite tip radius, Pei is the Peclet number for i, mi is the liquidus slope, C0,i is the initial concentration for i, ki is the partition coefficient for i, ζc(Pei) is a function of the Peclet number, Iv(Pei) is the Ivantsov solution (i=Cr or Al) and Ghkl is the average temperature gradient at the dendrite tip.
Reduction of grain boundary formation along molten pool centerline is induced.
The metallurgical factors avoid stray grain formation and improve crack-resistant microstructure development.
Competitive grain growth mechanism in three dimensions during directional solidification of a nickel-based superalloy.
Three-dimensional in situ characterization of phase transformation induced austenite grain refinement in nickel-titanium.

A limited number of reactors use mixed uranium-plutonium fuel which increases the primary use of the uranium raw material.
It is evident that gradual increase of embedded deformation leads to increase in recrystallized grain share.
At lower deformation levels recrystallization behaviour is observable on the borders of casting grains only, at higher levels of deformation the recrystallization can be already found inside of grains.
It is evident that next to the grain borders recrystallization takes place easier also on the specimen surface, where it makes a very homogenous belt of fine grains.
Large non recrystallized areas are clearly visible within recrystallized grains.

The result is the grain size of ZnO pellets increased with increasing sintering time and pressing pressure.
However, this has been extensively research recently and a huge number of scientific publications on ZnO due to its important properties and performance in optics, electronics, piezoelectric and photonics.
The grain size of each ZnO sintered pellet is tabulated in Table 1.
Grain size of pellets increased due to the process known as grain growth.
During sintering, some grains were grown, some even consuming others.

The grain size was determined using a linear intercept method from a large number of nonoverlapping measurements.
Fig. 2(a) is an optical micrograph of as-cast GW103K alloy, which shows that significant quantities of the eutectic phase decorates the grain boundaries and triple points.
There is no any obvious difference between the optical microstructure of aged specimen and that of solutionised ones, and the grain size doesn't change during aging.
The grain size of GW103K, GW103K+0.4Ca alloy, GW93K+0.6Ca alloys in T6 condition, is 40, 37 and 42 µm respectively, which exhibits a small difference.
Ca segregates to the grain boundaries and exists in the cuboid-shaped particles with a trace concentration.

It has been confirmed that the films possess polycrystalline nature with orthorhombic phase and the grain size of the films vary from 27.92 to 81.37 nm.
Table 2 shows the calculated grain size of BiSb2S3 as deposited and annealed thin films at various temperatures.
The higher temperature annealing result in a decrease in the bandgap energies of the films which may be attributed to the improvement of grain size in the annealed films [11,12].
The grain sizes of the films were found to increase with the increasing annealing temperature as well as increase in thickness.
It has been confirmed that the bandgap energy decreases with increase in annealing temperature due to the expansion of grain size.