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Then phosphors were washed to remove the excess of CuxS and ZnO from the grain surface.
The grain size of the phosphors and quality of phosphor surface were estimated with the scanning election microscope Tescan VEGA 3 SBH.
As could be seen at the figure 3, the electron-beam treatment of the initial batch of the phosphors changes their phase content that leads to the increase of the relative number of “green” centers of luminescence in the structure of the phosphor.
Evidently, doping the phosphors with Cu leads to the grain size growth, as shown in figure 4.
Since the radioluminescence is the surface process, the coalescence of the particles typically happens at low Gibbs free energy at the surface in the points of contact of the grains [10].

In other words, if an LLFP element can form liquid phase at relatively low temperature, it can be stabilized as grain boundary phases in silicon nitride ceramics.
The phase transformation did not contribute for the densification, may be due to small grain size of Si3N4 and good wettability of the formed liquid.
Brighter portion is grain boundary phase containing heavier elements, cerium.
After sintering at 1450o C, grain growth of Si3N4 particles was not observed, and only small number of tiny columnar grains are observed.
Cerium exists at grain boundary and form a silicate of +3 valence.

Based upon our previous work [6-14], nanocrystalline WC grains (core) are covered homogeneously by cobalt film or rim and they constitute primary nanocomposite particles, thereby enhancing wetting of WC to Co binder and inhibiting coalescence and growth of WC grains during sintering.
There is another interesting tentative idea to prepare nanocomposite WC-Co powder consisting of grains with a Co core / WC rim structure.
It is revealed that the WC / Co interface possesses strong bonding through three approaches: internal thermal stresses acting at grain boundaries, equilibrium thickness of intergranular noncrystalline films by force balance and grain boundaries.
The carbide surface energy ( BVγ = 2.475 ± 0.200 J·m-2) > cobalt surface energy ( AVγ = 1.900 ± 0.200 J·m-2) > carbide grain - boundary energy BBγ = 0.990 ± 0.300 J·m-2 > carbide - cobalt interface energy ( ABγ = 0.575 ± 0.200 J·m-2, angle of contact = 0º ± 2º).
Conclusions Nanocomposite WC-Co powder consisted of grains with a Co core / WC rim structure was prepared by precipitation covering - continuous reduction / carburization method.

It has a large number of goaf and a variety of no recovery wooden support and some carbon-containing organic material.
The large number of small coal mines within the mining area has historically been up to over 200, spread throughout all the mining area.
Roof was the dark gray siltstone containing plant fossils, fine-grained sandstone on top of the black siltstone; bottom was the gray siltstone, clay cementation, bedding and development, containing a large number of fossils of plant roots.
Roof was black clay rock containing plant fossils, fine-grained sandstone on top of the black siltstone; bottom of a dark gray mudstone, soft and unstable.
Mudstone under the fine-grained sandstone and it has clear horizontal bedding, sandwiching a black sandy clay rock.

The diameter of whisker is much smaller than grain size (average Sn grain size is 35µm).
It is characteristic that whiskers form mainly around grain boundaries.
In the case of the Sn without the tensile stress, the number density of whiskers is greatly lower than that of the Sn with the tensile stress.
The deformation induces multiplication of dislocations and their conservative motions, resulting in their local accumulation around grain boundary.
density of dislocations accumulated around grain boundaries.

A heterogeneous microstructure composed of nano-scale recrystallized grains and non-recrystallized austenite zones was promoted.
In addition, the prior austenite grains (PAGs) are favorable sites for the precipitation of the carbides, as shown in Fig. 3(b).
The ultra-fast tempering experiments of S900 steel were funded by the financial assistance of Business Finland, project FOSSA-Fossil-Free Steel Applications- grant number [5498/31/2021.
Gil Sevillano, Rapid transformation annealing: A novel method for grain refinement of cold-rolled low-carbon steels, Metall.
Karjalainen, High-Speed Erichsen Testing of Grain-Refined 301LN Austenitic Stainless Steel Processed by Double-Reversion Annealing, Metall.

Nevertheless this model neglects the strengthening effect of the pearlite lamellar spacing within the perlite grains.
σ=k1+k2d (2) Where σ is the yield stress, k1 and k2 are the contributions from other strengthening mechanisms and d is the grain size.
In lamellar graphite iron the eutectic cells can encapsulates a number of individual primary dendrites.
Although both samples have similar eutectic cell size, considerably larger number of primary dendrites traverses across the eutectic cell of the low carbon content sample as can be seen in Fig. 8(b).
For example the LGI 2 microstructure in Fig. 9 can be considered stronger than the LGI 1 due to the larger number of primary dendrites that exist within the eutectic cell.

Tailoring the property of magnesium by forming new alloys or new structures has been the main focus of a number of researches [1-4].
First of all, a number of alloying additions (e.g.
The grain size of Mg is reduced to 50nm after 60 hours of milling.
%Ag leads to a fast reduction of grain size to 30nm.
Grain size of various Mg-based alloys as a function of milling times.

Physical and morphological properties (density, knots, clusters knot, resin pockets, deviation of the grain, annual ring width position of board respect to the pith, humidity, etc.) along with mechanical and non destructive properties (elastic modulus, tensile strength, sonic pulse velocity) have been checked.
Sardinian timber is generally characterized by low quality due to the presence of defects (knots, clusters knot, resin pockets, deviation of the grain etc.), but it could be effective if used to produce Cross Laminated Timber (CLT) panels.
UNI 11035-1 [5] defines references for moisture content, direct or indirect evaluation of the density, the latter performed by measuring the number of growth rings contained in a reference line [9], limits to defects reducing the strength (knots, slope of grain, checks, splits, shakes), limits to geometrical features representing growth defects (wane and warp) and decay[10, 11, 12].
Measurements have been performed in the center of mass of the boards along the grain direction.
High values of twist and spring warping are strictly connected to great deviation of grain which is the main characteristic of Sardinian Maritime Pines.

The ultrafine grained AA1060 sheets were made by CR by Marnette et al.
The number of microvoids dramatically increased when deformation went from 50% to 95%.
The RTR-obtained grain size of AA2218 HEAp MMCs is 592 nm, whereas the CR-obtained grain size of AA2218 high entropy alloy particles metal matrix composite is 340 nm at 50% rolling deformation.
By 42.6 percent, the mean grain size has decreased.
Grain refining can increase material strength according to the Hall-Petch formula.