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Beach stability analysis Grain size grading of the ‘native’ and ‘borrow’ material is necessary for assessing the feasibility of a beach nourishment project.
The application of the beach fill model involves calculation of two factors, an overfill factor RA and a renourishment factor RJ, where: RA = the estimated number of cubic meters of fill (nourishment) material required to produce 1 cubic meter of beach material when the beach is in a condition compatible with the native material.
The values of RA and RJ are determined graphically based on the knowledge of the mean grain size and sorting characteristics of the native and borrow materials.
Figure 7 shows isolines of the overfill factor RA and renourishment factor RJ, where: MΦ= the mean diameter of the grain size distribution in phi units; σΦ= the standard deviation of the grain size distribution in phi units (a measure of sorting); subscript b refers to borrow material; subscript n refers to native material The survey of Chinese bay [4] and the report of Xiamen Xiangshan-Changweijiao beach restoration project, showed that MΦn=1.22, MΦb=1.44, σΦn=0.78,σΦb=0.55.
Shoreline turn to the status before fill placement, coarse grains remnant.

The inner pore and defect size of the material will reduce because the hydroxyapatite is made with nano-technology and nano-grain is small.
Because the grain size is small, the number of grain boundaries increased greatly, which provides sufficient opportunities for grain boundary sliding, leads to increase in deformation, facilitates the movement between grains, enhances plasticity, and reduces brittleness.
In addition to improve the mechanical characteristics, as compared with the existing artificial bone materials, the biggest advantage of nano material is that the consistency between the degradation rate of artificial scaffold in vivo and the bone growth rate can be achieved by controlling the grain size.

Introduction Low Energy High Current Pulsed Electron Beam (LEHCPEB) has been developed as a new surface modification technique that can be used for a high number of potential applications [1 - 3].
We can notice that we have two kinds of grains formed in the surface: large 20-25 µm together with some smaller ones having a size of about 5 µm.
Several large equiaxed grains of austenite transformed into a needle-like structure suggesting that the martensitic transformation was activated on cooling in some grains.
In addition, other equiaxed grains (2-5 µm in size) could be indexed with the b.c.c lattice.
It is also clear that the transformation was trigged in some γ grains, other ones were sufficiently stable.

Therefore, a large number of studies, have been conducted to explore the synthesis and applications of HZSM-5 zeolite due to its specific properties.
The grain size of sample 1# distributed between 30nm-100nm (shown as “Detail of 1#” in Fig.1).
The grain size of sample 2# distributed between 20nm-30nm (shown as “Detail of 2#” in Fig.1).
This can be explained by considering the fact that although crystal growth faster, the redissolution of grains occurs is much more easily at higher temperatures.
The average grain size was 20~30 nm, and the average particle size of the agglomerates was 300 nm at a suitable synthesis condition.

., initial grain boundaries and high angle boundaries within the original grains [2-4].
Interestingly, in the case of 5N specimen, very coarse grain structure could be observed just after cold rolling, which indicates grain growth occurred even at room temperature in high purity aluminum foils.
Commercial purity aluminum contains a number of impurities that influence the recrystallization behavior.
EBSD grain orientation maps of AA 1050 and Al 3N recrystallized at 315oC for 5 hrs.
EBSD grain orientation maps of fully recrystallized AA 1050 and Al 3N samples have been given in Fig. 3 and texture measurement results in Fig. 4.

Furthermore, due to the diminishing sources of antimony, tellurium and rare-earth elements, only metallic and non-metallic elements having a large Clerk number should be used for production.
Various magnesium-based alloys and compounds are directly synthesized in order to investigate the effects of grain size, composition, dopants and non-equilibrium states upon the hydrogenstorage behavior and thermoelectric properties.

The main objective of the present research is to obtain fine grain Ni/SiO2 chilled sound composite having very good mechanical properties.
A detail of melting and composite preparation is described elsewhere by number of researchers.
The microstructure reveals fine grain structure because of chilling.
This increase in tensile strength property is mainly because of fine grain structure obtained due to chilling.

Nanosized Powders of Refractory Compounds for Obtaining of Fine-Grained Ceramic Materials J.
One of the ways to produce ceramic materials with fine-grained structure is the application of nanopowders.
One of the aims of application of nanopowders is to obtain materials with fine grain structure and one of possibilities could be mixing of the standard and nanopowders.
Fig. 5 Characteristic shape of particles of used nanopowders: 1 - TiN; 2 - Si3N4-TiN; 3 - Si3N4- 80 wt.% SiC; 4 - Si3N4-6Y2O3-3Al2O3; 5 - β-sialon. 0 5 10 15 20 25 30 35 10 100 1000 size, nm % Particle size distribution of TiCN powder by number Size analysis by Zetamaster S , Malvern Instruments Ltd. 0 5 10 15 20 25 30 35 10 100 1000 size, nm % Particle size distribution of CrCN powder by number Size analysis by Zetamaster S , Malvern Instruments Ltd.
The main advantage of nanopowders application is the possibility to decrease the sintering temperature of ceramic materials and to obtain a structure with more fine grains.

It is commonly believed that there are three major mechanisms of white layer formation [5]: (1) Phase transformation as a result of rapid heating and quenching, (2) Severe plastic deformation that results in ultra fine grain size (10~300nm) due to grain refinement and/or recrystallization effects, and (3) Reaction of the surface with the environment.
Table 1 Chemical composition of SKD-11 (in weight) Element C Cr Si Mn Mo P< S< V≤ Content [%] 1.40-1.60 11.0-13.0 0.40 0.60 0.80-1.20 0.030 0.030 0.20-0.50 Table 2 Grinding parameters Group number Specimen number Grinding speed [m/s] Feed rate [mm/s] Grinding depth [mm] Remarks A 1 19.6 6 0.03 Down grinding, Without coolant 2 19.6 6 0.08 3 19.6 6 0.12 4 19.6 6 0.15 B 5 19.6 3 0.10 6 19.6 6 0.10 7 19.6 10 0.10 8 19.6 15 0.10 In the experiments, the grinding forces were measured by Kistler 9272 four-component piezoelectric dynamometer, and the grinding temperature was measured by thermocouple.
Fig. 6 shows the metallurgical structure of Specimen 1 and 2, which compared with that of bulk material (Fig. 5), indicates a dark layer with homogeneous dark grains filled in the material beneath the ground surface.
A white layer with fine and homogeneous grains and small size circular carbides was formed beneath the ground surface and then a transition layer distributed both dark and white grains was between the white layer and the dark-etching layer.
The white layer with fine and homogeneous grains and small size circular carbides is favorable to the performance and life of products, and the dark-etching layer with the tempered structures is prone to produce crack on the surface so that the product life will be shortened

Under the continuous layer of titania, there was a fine-grained zone composed of mixed oxides.
The Ti-45.9Al-8Nb discs were ground with emery papers up to 1200 grit number, washed with distilled water and acetone.
The powder mixture was composed of 25 wt.% silicon (grain size not exceeding 0.04 mm) and 75 wt.% alumina.
The outermost very thin layer is composed of alumina outgrowths, the subjacent continuous layer is built of columnar titania grains.
Underneath, there is a fine-grained 'mixed oxide' zone containing oxides of all alloy components.