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Montero and Martin (2003) analyzed the Hölder spectrum of 20 samples based on soil laser diffraction, and showed that the combination of laser diffraction and Hölder spectrum analysis is a potential tool for detecting changes in soil grain distributions.
Sampling was performed at two depths (0 cm to 20 cm and 20 cm to 40 cm) in each plot, grain size was measured using MasterSize2000 (particle size measuring range from 0.02 μm to 2000 μm).
The data of the content of 100 grade soil grain was obtained, and the soil was the sandy loam（Table 1）.
In the intervals, the number of cells of equal sizes for k =1 to 6 were considered.
Holder spectrum of dry grain volume-size distributions in soil.

Fig. 4: SEM Analysis of 0% incorporation of maize straw Fig. 5: SEM Analysis of 5% incorporation of maize straws Fig. 6: SEM Analysis of 7.5% incorporation of maize straws Fig. 7: SEM Analysis of 10% incorporation of maize straws The micrograph in Figure 4 which is the control concrete without maize straw addition has many concrete grains connecting one another to form a single solid body having numbers of holes or defects acting as regions of discontinuities within the concrete.
The presence of holes or voids could be linked with air trapped within the concrete grains during processing which later open as voids after curing/setting.
After the addition of maize straws, the spatial arrangement of concrete grains appears different from that of the control.
The number of defects seen on the surface of the microstructure (Fig. 4) is fewer compared with those in Fig. 4 to Fig. 7 where most of the concrete grains appear disjointed.
The microstructure in Fig. 6 appears better than that in Fig. 4 because its number of surface defects are lower than those in Fig. 4 but its lower compressive strength than that of the control could be linked with the weakness of the structure developed from the interaction of the maize straw (7.5%) with that of concrete since the maize straw itself is weaker than the concrete.

They used the nuclear properties of 26Al and measured the 26Al tracer diffusivity in coarse-grained (grain size 130–200 µm) polycrystalline a-alumina and claimed that bulk diffusion was predominant.
(6) where is the correlation factor (»1), the number of equivalent nearest neighbour sites, the distance between equivalent sites and the attempt frequency (»1013 s-1).
Grain Boundary Diffusion of O and Al.
At one has the concentration in the grains.
Near the grain boundaries (r » R) the equilibrium concentration, , will be reached rapidly since the mullite/mullite grain boundaries act as fast diffusion paths.

The average particle diameter was around 20-30 nm, calculated by considering that the grains were spheres.
It is possible to observe grapefruit-like grains with nanometric dimension between 25 to 80 nm.
The peaks broadening are indicative of nanostructured grain size.
The number of HGF-CEMP1 cells attaching to ZnAl2O4 nanostructured material surface showed an increase of 53, 81 and 86% at 180, 300 and 420 min (p<0.05) when compared to controls.
The spherical nanophase as showed by the images of the topography by AFM and SEM has a grain size of around 20-30 nm.

Suresh et al. [29] have highlighted the influence of the grain structure and slip characteristics in aluminum alloys.
During testing, the number of cycles and crack extension data were recorded until specimen fractured.
The etched microstructure consisted of elongated grains.
Another obvious feature revealed in the section was the secondary cracks along the grain boundaries.
The crack(s) started propagating along the grain boundaries but stopped up afterwards.

One way to reduce the number of these elements is to use 3D printing.
The resulting grains then grow in the direction of the heat flux across the powder layers.
The microstructure of the grains formed in this way as reported in the literature [13, 16] is then made up of a cellular substructure.
o These inclusions precipitated mainly along the grain boundaries and then in the grains volume
- The heat treatment procedures used lead to the removal of the cellular substructure and polygonization of austenite grains boundaries

It significantly affects on the process of nucleation and grain growth [5] and type of the crystallizing phases.
When the grain decreases, the strength increases.
On its basis, increase of the yield strength limit with decrease of the grains size can be explained, determined usually by image analysis of a metallographic specimen.
In the casting structure, the grain size can be described by a direct parameter, i.e.
The series of the high pressure die casting (HPDC) were made, obtaining an adequate number of adherent samples for the mechanical properties testing (the same casting conditions as in the casting process).

(22) Where: -velocity of water surface (); -distributed parameters of flow velocity, =0.6; -relative depth of water from water surface.The vertical mean flow rate can be calculated with integration: (23) According to fig.3, the velocity of water at the buoy position is: (24) When study the project, hydraulic factors and grain diameters of bed material at the section Huanglinmiao were tested, the test result is shown as Tab.1.
Tab.1 Hydraulic factors and grain diameters of bed material at the section Huanglinmiao Number of viewing perpendicular 1# 2# 3# Number of viewing perpendicular 1# 2# 3# Water temperature (°C) 23.2 23.8 22.4 Depth of water(m) 17.1 63.2 60.87 Distance to start point (m) 510 350 310 Discharge section area(m2) 17922 18530 17092 Viewing time interval (s) 2.27 2 0.57 Width of river surface(m) 504 511 495 Rate of flow(m3/s) 30000 42200 11200 Gradient of water surface (‰) 0.102 0.181 0.019 From TAB.1, the water flow of No.2# is maximum, water depth is maximum, mean flow rate is 2.27m/s, so No.2# was chose as the fixed position for monitoring platform when study the project.
Tab.2 Design parameter Length of buoy 50 Viscosity resistance coefficient 0.4 Diameter of buoy 0.2 Density of river Diameter of mooring cable 0.006 Mean flow rate of river on buoy position Density of mooring cable Lift coefficient 0.07 Modulus of elasticity for mooring cable Mass of buoy 1463 Coefficient of initial force 1 Angle of mooring cable and river bottom (°) Depth of river 63.2 Number of mooring cable 6 Distance from buoy to river surface 10 Total buoyancy 17240 Response of buoy.

Introduction Bismuth layer structured ferroelectrics (BLSFs) belong to the Aurivillius family of compounds with a general formula (Bi2O2)2+(Am-1BmO3m+1)2-, where A=Bi3+,La3+,Sr2+,Nd3+; B=Ti4+,Fe3+,Nb5+; and m refers to the number of perovskite-like layers between Bi2O2 layers[1-4].
There were no indication of second phase in the system indicates that a single phase-layered perovskite structure were formed (JCPDS number 73-2181).For the mass difference and ionic radius difference of both A and B sites.
The crystal lattice has some distortion and diffraction peaks have a deviation from the standard sample (JCPDS number 73-2181).
The SEM obtained fot Y-BSNNF pellet shows the presence of extended plate shaped grains associated with inter and intra-porosity, similar to other bismuth layered perovskites[7].
The average grain diameter is about 2.5um and thickness 1um.

It could be found in Fig.3 that the inclusions in steel B had a grain appearance.
However, secondary refining was adopted in Steel A, which caused that there were less inclusions in steel A and the inclusion were mainly not banded sulphide inclusions but grain oxide inclusions.
Because of the great number of long sulphide inclusions in steel B, the number of pitting corrosion sources was large, which led to anode current density increased abruptly.
The shape and number of inclusions in low alloy steel could be changed by metallurgy technology and heat treatment.