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These sinks can be from grain/lath boundaries, oxide nanofeatures to actual radiation-induced voids or bubbles, which can even become the dominant sinks in the system [12].
The critical size is sensitive to a number of environmental and physical parameters [26].
While the positron lifetime is roughly proportional to the increasing nano-void size, an increase in the number of helium atoms in nano-voids decreases the lifetime [22].
The S parameter was defined by the ratio of the number of counts at the centre of the energy peak of the annihilation gamma rays (range, 511 ± 0.64 keV) to the number of counts for the entire range (range, 511 ± 12.79 keV).
Dpa represents the average number of displacements per atom, Tirr [°C] is the irradiation temperature and cHe [appm] is the concentration of helium produced in material [47].

Caballero et al. [8-10] carried out a vast number of investigations on the formation and characteristics of bainite.
To reveal the prior austenite grain size, an etchant was used, which is composed of saturated picric acid C6H4(CH3)2 and hydrochloric acid [2].
The prior austenite grain size was evaluated by a standard linear intercept method.
The average prior austenite grain size for these heat treatments is between 10 and 14 μm.
One might be that, although the prior austenite grain size is constant, the microstructural size of the bainitic structure is changed.

An increase in doping led to a decrease in grain size.
The addition of NZTO causes more stress, which causes atoms to rearrange and larger grains to grow.
The pure thin-film grains (Fig 6-A) seem to have few pores and a non-smooth surface.
Additionally, the number of black particles observed on the surface increases, indicating the formation of dopant-rich regions or secondary phases.
This increase is associated with an increase in the number of free electrons and therefore the number of holes transferred by oxygen ions [48].

A large number of core analysis, drill results and test mining research has confirmed that the study area is constructed by the strong force, the micro-cracks are well developed, it is not only important reservoir space, but also the flow of oil and gas wells to obtain high yield important seepage paths, is to obtain yield the necessary conditions.
Pore types and structural characteristics Through a large number of core observation, microscope, scanning electron microscope, mercury intrusion analysis, results show that, ShiWu broken faulted layer clastic rock reservoir space genetic types are dominated by secondary porosity.
Major types of secondary porosity[1] include intergranular pores (heteroaryl between particles, or carbonate cements,or edges and corners of particles, etc, were eroded or metasomasised, formation of intergranular porosity), intraparticle pores (formed after detrital internal component’s partial dissolution or metasomatism), intergranular pores (pores between clay minerals ceramic), cast film pores (formed after detrital grains have all been dissolved or metasomasised, and retention of the original particle morphology) and cement dissolved pore (mainly formed after dissolution of carbonate cements).

Specimens of a line are numbered from ‘A’ to ‘I’.
Outer two 105x105x105mm cubic specimens are used for MCWR measurements of radial-tangential direction (RT-direction) and longitudinal direction (L-direction) of wood grains.
Screw directions of specimens ‘C’ and ‘G’ are close to Tangential(T) and Radial(R) directions of wood grains respectively.
It is considered differences between three rows are reflecting the effect of angle of the grain, etc.
The effect of grain on shear strength is a little greater than those on withdrawal resistance measurements.

The interval between the spray nozzle and the collector was maintained at (10 ± 1 cm), the spray solution volume was (50 ml), the spraying number was (20), and the interval between the sprayings was (5 sec).
It portrays a homogenous distribution and dense uniform spherical crystalline grains with an average size ≤ of 0.8 µm for a flat sample and ≥ 1 µm for cylindrical design.
The developed grains upon the surface being irregular in a spherical form and densely packed.
The grains homogenously distributed inside the area of scanning.
Komem, The effect of grain size on the sensitivity of nanocrystalline metal-oxide gas sensors, Journal of Applied Physics, 95(11) (2004) 6374 - 6380 [16] G.F.

Due to the interaction between atoms, so the valence electron energy levels of individual atoms can be combined into a band when large number of atoms combine to form a solid, it makes the continuous band of the bulk material narro ，then restored gradually and split into discrete energy levels.
Beard and other tests [11] showed that when the grain size of the silicon nano is 9.5nm (equivalent Eg = 1.20ev), it can trigger multiple exciton generation of quantum yield of 260% [12].
Timmerman and other tests [13] showed that it will produce a two-photon process between the silicon nanocrystals when the silicon nanocrystals as 3.1nm and the grain spacing as 3nm. e.g
(2) It is the photon energy of the incident, the incident photon generates an electron - hole pairs in the first silicon grains at first and then the excess energy stimulating the adjacent silicon grains by Auger process to generating excitons.
The effective quantum dot array must have two demand, which is the size of silicon nanometer grain close to the consistent and the distribution of density close to equal.

The chemical composition of produced stainless steels are given in Table 1 in which steel number 1 is the reference DIN X45CrNiW 18-9 steel which was melted in air atmosphere.
Steel 4 shows finer grains of the scale comparable with steel 1.
It is clear that the presence of nitrogen in absence of nickel render the oxide film more fine grained as shown in Figure 7.
On the other hand, steels 3 and 7, with moderate values of nickel and nitrogen, show more compact texture with more fine grains, which at the same time showed lowest steady state mass gain and oxidation rate constant and the highest activation energy.
Yurek “Effect of alloy grain size and silicon content on the oxidation of austenitic Fe-Cr-Ni- Mn-Si alloys in pure O2", Oxid.

Detailed information on de-percolation threshold of capillary porosity in cement paste with dispersed aggregate grains surrounded by ITZs is missing.
Size of the representative volume element (RVE) for composition is three to five times the maximum grain size [12-14].
The " wall effect" in the fresh state is known leading to relatively inferiour cement packing densities in a thin layer near to the aggregate grain's surface [18].
(2) The connected fraction of porosity is concentrated in the contact layer of aggregate grains with a thickness less than 1µm.
[7] S.Diamond, S.Mindess, and J.Lovell: On the Spacing between Aggregate Grains in Concrete and the Dimension of the Aureole de Transition.

The evolution of these two families of grains has been determined by studying a specific detector angular section of 15°; 352.5° to 7.5° and 172.5° to 187.5° for the parallel and 82.5° to 97.5° and 262.5° to 277.5° for the perpendicular direction.
This angular range was chosen to sample a sufficient number of grains to obtain a statistically relevant signal. 1-D patterns were obtained for these zones of the 2-D patterns.
A fit of individual reflections to a pseudo-Voigt profile function was used in order to study the stress partitioning between subsets of grains having specific {h k l} plane-normals oriented parallel and perpendicular to the loading direction [14].
For a grain family having {hkl} aligned axially, the resolved stiffness depends upon the cubic elastic anisotropy factor , where greater A{hkl} implies greater stiffness [16].
Within the grains, the microstructure is highly refined, and is characteristic of lath martensite that forms during rapid cooling of steels.