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Their importance in grain production has been increasing due to their high yield capacity and lower harvest cost in comparison to other grains [1].
These authors found that the extent of increase of axial effective thermal conductivity with increase of flow rate was larger than that for radial conductivity, but is coincident when the Reynolds number tends to zero.
Kunii and Smith [10] also published data on thermal conductivities of particles bed with flowing fluids, concluding that the flow contribution in the steady state equation is not linear in Reynolds number and is affected by particle diameter.
Elsari and Hughes [11] also performed experimental investigations to measure axial effective thermal conductivities of packed beds for a number of particles and catalyst pellets.
Another important observation was lower differences between bed inlet and outlet temperature for higher air flow conditions, which indicates higher homogeneity in the heat distribution inside the system for higher Re numbers.

Intorduction The method of laser cladding with manual wire feeding allowed to reduce the quantity of machining of products after welding, since allowance for subsequent machining are less than 100 microns, and are substantially in a geometric tolerance after cladding [1], and zones of thermal inluence are at level of hundreds of microns, and the deposited layer has a fine-grained structure [2].
For a number of defects their preliminary preparation with the use of very hard and durable tools is required.
Nickel Ni ~ 1.6 - 2% refines the grains, improves the ductility of steels without their weld ability deteriorates.
During the external examination of the deposited samples of pin compounds number 1 and number 2, cracks, incomplete fusions and other defects were not found.
The microhardness of sample 2 has a number value slightly lower than the base material of the workpiece.

During cooling the secondary α growths from previous β grains in a plate like form.
The metallographic preparation followed the standard sequence of sandpapers and alumina polishing up to 0.3 μm grain size.
Regardless of the coupon geometry, the stress x number cycles (S-N) were obtained as the result of bending momentum.
In the figure, it can be seen the prior β phase grain boundaries enclosing α’ martensite grains.
However, these numbers could be considered quite inaccurate because the unique visible β peak appears around 39°.

In polycrystals the PSBs are generally formed in the surface grains which have suitable orientation for slips to occur.
In high-cycle (low strain) fatigue, the damage process associated with the plastic deformation occurs in localized regions on a micro (grain size) scale.
Figure 3 shows the damage parameter Ψ, LHS of eqn. (9), versus number of cycle to failure, fN , in a log-log scale.
Figure 4 shows the log-log plot of the driving energy versus number of cycles to failure.
A fatigue criterion is then obtained by correlating the driving energy ( + + e p W W ∆ρ∆ / ) to the number of cycles to failure fN to produce a master life curve.

Results and discussion Fig.3 shows the results of the laser bending tests in terms of bending angle as a function of number of laser passes and scan velocity for both foams.
By increasing the number of passes, the bending angle always increases as well as by decreasing the laser power (because of the reduction of the input energy).
During laser forming, some defects can be observed because of the laser-foam interaction (Fig.4), above all at high number of passes.
In the external part of the sample, the typical eutectic structure of the aluminium alloy is characterized by a coarse grain size probably due to a low cooling rate from the melt during the foam production.
Large eutectic grains are visible far from the laser processing area, and a homogeneous fine structure is visible in the HAZ.

The average grain size of the 8 µm foil and the 20 µm foil is 3 and 10 µm, respectively.
The effect of grain size might be important to the fatigue strength.
The number of cycles to failure is Nf=1.4x105.
Relation between strain and number of cycles 80x10-3 60 40 20 0 Strain, ε 100 101 102 103 104 105 Number of cycles, N cycle εmax εmin Figure 11 shows the relation between FWHM and the maximum strain.
The full width at half maximum, FWHM, was a function of both the applied stress and the number of stress cycles.

The morphology of the sample was observed with a large number of pores for the sample that was prepared using planetary ball-mill.
The presence of a high number of pores indicated that the grains were not in good contact with one another, suggesting a low density.
Large number of pores causes higher resistance in the sample [9].
Denser microstructure led to the higher conductivity while a large number of pores reduced the conductivity of the sample.
It can be concluded that the ball-milling process effect the microstructure of the sample which reduces the interconnection between grain and increase the porosity of the sample.

Combined with the standard for classification of soils in the "geological and mineral sectors test methods of soils", these soil particles with similar geotechnical properties are classified according to particle size, and the grain group is divided into: boulders, pebbles, gravel particles, sand, silt and clay.
Because the dredger fill in this study is fine-grained soil, and the particle content of the boulder, pebble and gravel grains are small in the composition of the soil, analysis on the granulometric composition of sand, silt and clay was only made and the soil was named as shown in Table 1.
As the dispersing agent mainly disperses the aggregated particles, it is normally believed that clay exhibits flocculation, which can further agglomerate together in large numbers, to create even larger particles that are called “fake silts”.
Table 4 Physical characteristics of different coastal regions Sampling Spots Particle Density Liquid Limit Plastic Limit Plasticity Index Clay Content Activity Index Naming as the Plasticity Chart ρs ωL ωP IP <0.002mm A=IP/(Clay Content) g/cm3 % % — % Tianjin 2.68 43.47 23.83 19.66 48.08 0.41 High Liquid Limit Clay Dalian 2.57 51.71 30.72 20.81 48.18 0.42 High Liquid Limit Clay Caofeidian 2.59 35.21 22.12 13.08 17.08 0.76 Middle Liquid Limit Clay Huanghua 2.59 29.58 — — — — — Qingdao 2.68 27.46 — — — — — Lianyungang 2.72 50.79 29.04 20.78 28.69 0.72 High Liquid Limit Clay In addition, in fine grained soils, naming the soil only on the basic of the particle size doesn’t accurately reflect the geotechnical properties of the dredger fill.
Conclusion The following conclusions can be drawn from the above research: 1）The diameters of the soil particles in the Bohai Bay coast are relatively small, and the typical grain sizes are mainly clay sized; 2）According to the granulometric composition and mineral composition, there are many kinds of dredger fill in the research area, such as heavy clay, silty soil, light clay, silty loam and so on; 3）The mineral composition for the soils tested has high variation in the sampling area.

Its constituent mainly consists of metallic matrix, flake graphite and eutectic composition in grain boundary.
To ensure higher mechanical properties of casting, a large number of scrap steel is adopted in foundry instead of pig iron.
For example, using silicon-barium inoculants, its inoculation addition amount is one half of the ordinary Silicon iron. (3) Inoculants grain should be appropriate.
Larger-grain inoculants cannot be absorbed quickly by molten iron.
The residual larger-grain inoculants mix with castings will deteriorate casting performances.

Norman et al. [2], for example, showed a reduction of grain size by two orders of magnitude by modifying an AlCu4.5 alloy with 0.55wt% Sc.
As illustrated from the etched microsections, the deformation of the grains was more pronounced for P1 than for P2 and also for the higher strain rate for a given temperature.
The only sample that showed recrystallized grains, probably formed immediately after hot deformation just before water quenching, was the one deformed at 400◦C and 10s-1.
However, the sample deformed at 200◦C and 10s-1 showed some deformation bands inside the deformed grains in P1.
The work is fostered in the TAKE OFF funding program with the project number 839002.