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Particle size has been shown to promote uniform corrosion rather than a localized dissolution along grain boundaries [6].
The agglomeration and grain growth tends to happen in acidic environment due to the particles in the morphology were fused with each other and produced larger particles with size (111.78nm).
The CoNiFe nanoparticles exposed in alkaline environment produced the smallest particle size of 71.06 nm due to the existence of high number of boundary atoms in dendritic grain boundaries.
The existence of many grain boundaries in the dendritic structure was the main contributor for the particle size reduction [7].

A semiquantitative evaluation of the phase content was carried out using the corundum number RIR (Reference Intensity Ratio) by the Chung method.
The shape, size and chemical composition of the grains were examined by scanning electron microscopy using JEOL JSM 6390-LA microscope, shooting conditions: electron beam accelerating voltage 15 kV, SEI, BES, working state 10 mm, magnification up to 30,000 times.
The results of electron microscopic studies have shown that amorphous silica is composed of pulverulent, friable, neo-canted, spherical-shaped grains.
The distribution of elements along the grain and their alignment shows that the material under investigation consists mainly of pure SiO2, (Fig. 6).
Distribution of elements along the grain and their combination.

This was followed by a solution treatment at 1063 K for 10.8 ks (the solution treatment is abbreviated to “ST”) in vacuum with subsequent water quenching for grain refinement.
The average grain sizes of H-ST and S-ST were ≈14 μm and ≈16 μm, respectively.
Furthermore, it is noticed that there is a precipitated free zone (PFZ) near a grain boundary that is not related to the microsegregation.
The results of the fatigue tests that shows number of cycles to failure at each maximum cyclic stress for S- and H-samples subjected to ST, AT43.2, and AT259.2 are shown in Fig. 6.
The number of cycles to failure at a maximum cyclic stress of 700 MPa for S- and H-AT43.2 is 34,460 cycles and 2,435,170 cycles, respectively, which is a significant difference.

Number of papers containing the keyword "stent" in the last 35 years Classification of types of stent coatings Stents have coated and uncoated types.
After this fatigue test slip lines and grain boundaries occurred, but the coating remained uniform (Fig. 12, 13).
The coating has different thickness on the lighter and on the darker parts because bigger atomic number gave lighter shade and smaller atomic number gave darker shade therefore there is thicker the silicone layer on the darker parts.
Slip lines occurred, grain boundaries were outlined, so the roughness was grown locally, because of the anisotropic plastic deformation, but the coating did not change significantly.
Nam: The role of carbon on the occurrence of grain boundary serration in an AISI 316 stainless steel during aging heat treatment, Materials Letters 59 (2005) 1439-1443

When used as element sensors have as main feature their microstructure, which consists of grains, grain outlines, and when porous have a large surface area.
Fig. 5b and Fig. 5c, for films with 12.5 and 15 % (weight) of ZrO2-TiO2 respectively, show very similar images regarding the sintering stage and the number of pores.
It is possible to observe a better homogeneity in the sizes and shapes of pores, as well as the grain components of the microstructures of 12.5 and 15 % (weight) films.
Despite the different numbers of layers deposited to obtain each film, the thickness measurements indicate very close values, whose average is approximately 55 μm.
The differents numbers of layers deposited to obtain each film, the thickness measurements average is approximately 55 μm and classifies these films as thick.

The grain size of the tube body was 11.5μm, which is smaller than that normally used.
Samples were taken from the site where a transverse crack was found by NDT and the sample number was 2# (transverse crack).
The tube body, weld and HAZ of the failed coiled tubing were all F+P, with fine grain size of 11.5μm.
When the lateral crack on the outer surface was opened, the low-power analysis showed that the crack section presented several step-like features, and the crack surface of each step had obvious shell grain lines.
A number of fatigue striations perpendicular to the crack propagation direction and basically parallel to each other were observed at high power by SEM.

Analysis results with respect to the morphology are showing that grain size of top surface appeared small in case Ar gas pressure increases.
From the results, the Mg films deposited at high Ar gas pressure exhibited fine grain structure.
The relative value of Mg surface energy can be calculated by γ=PUc/ZN∆S [γ=surface free energy, Z=Coordination number, N=6.02×10 -23 number/mol (Avogadro number), ∆S=Mean surface area of an atom, P=Number of the bonds, Uc=Cohesive energy].
Through the results of the monitoring experiment, the Mg thin film of fine grain structure, obtained at high Ar gas pressure of 1×10-2 Torr exhibited excellent corrosion resistance.

Tests concerning solid warehouse static side pressure of large diameter silo has been performed respectively by Li [5] and Yuan [6] in state grain storage, after multiple testing it found that test results is less than the standard value of static lateral pressure of shallow bin.
The stored material used in the test is standard sand in FuJian PingTan (Table 1), followed are each index of the sand’s physical properties: grain size gradation, particle diameter D>0.65mm accounts for 3%, D =0.45~0.65mm accounts for 40±5%, D=0.25~0.4mm accounts for 51±5%, D<0.25mm accounts for 6%.
Table. 6 The comparison between static and dynamic pressure value of the measuring point in Group A in the eccentric discharge when open 1# discharge port Number Depth [m] Specific value [kPa] Static pressure value [kPa] Dynamic pressure value [kPa] Increase values [kPa] Increase magnitude 982# 0.1 0.58 0.3341 0.5122 0.1781 53.30％ 1003# 0.3 1.74 1.644 3.3024 1.6584 100.86％ 1034# 0.5 2.9 2.4846 2.3204 0.1642 6.61％ 981# 0.7 4.06 4.2604 4.4540 0.1936 4.54％ 1001# 0.8 4.64 4.8813 4.9699 0.0886 1.81％ 1035# 0.9 5.22 5.5152 5.6639 0.1487 2.70％ 1020# 1.0 5.8 6.3163 7.1172 0.8009 12.68％ 990# 1.1 6.38 7.0068 6.9657 -0.0411 -5.87％ 995# 1.2 6.96 7.6842 8.0126 0.3284 4.27％ Table 7 The comparison between static and dynamic pressure value of the measuring point in Group C in the eccentric discharge when open 1# discharge port Number Depth [m] Specific value [kPa] Static pressure value [kPa] Dynamic pressure value [kPa] Increase values [kPa] Increase magnitude 988# 0.1 0.58 0.2262 0.1885 -0.0377 -
Lohnes, Grain bin over pressures induced by dilatancy upon unloading, ASAE Paper No.80-3013, American Society of Agricultural Engineers, St.
Li, Testing and analysis of Large diameter grain SILO wall pressure, Master's Thesis of Zhengzhou Institute of Technology, 2002

It is very difficult to obtain a mathematical model of such a complex and multifactorial dynamic process with a large number of variables.
The first hydration bonds between the particles appear in about an hour and in another hour a gel forms on the surface of the cement grains [20].
The use of superplasticizers leads to a change in the morphology of hydrated new growths, the classical fibrillar structure of the surface of cement grain transforms into a globular structure [22].
At the same time, a large number of grains of crystallization and the rapid growth of crystalline hydrates lead to the occurrence of internal stresses, destruction and restructuring of the crystal lattice, which causes sharp jumps and drops in the strength of the cement stone at an early age of hardening.
A number of researchers [5, 8, 11, 26 – 29] have noted an abrupt increase in the strength of artificial stone based on cement binders.

A fine-grained and smooth-faced coating was obtained at TNmr =2, which exhibited the highest corrosion resistance in 3.5% NaCl environment.
It could be seen that there are coarser grains and some directional ditches on the surface of coatings from baths with TNmr =0 and 1 (Fig.2a and 2b).
With the increasing TNmr up to 2 the coatings become uniform, smooth and finely grained (Fig.2c).
Fig.3 Dependence of the polarization curve (a), and Nyquist plots (b) for Zn-Ni coatings in 3.5%NaCl, on the TNmr value in plating baths at a deposition current density of 2A/dm2, the number in diagrams represents the TNmr value.
This is related to its significantly higher Ni content, more uniform and finely grained surface.