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Modes of high-strength titanium alloys TIG welding Welding mode number Welding current [А] Arc voltage [V] Welding speed [m/h] Filler wire speed[m/h] Welding heat input [kJ/m] 1 350 12 10 - 1512 2 380 12 16 - 1026 3 350 12 8 60 1890 Results Studies of the titanium alloy Ti-6.5Al-3Mo-2.5V-4Nb-1Cr-1Fe-2.5Zr welding joints structure made it possible to conclude that the weld metal obtained by the TIG welding in the state after welding also consists of equiaxed grains of metastable β - phase elongated in the direction of heat removal (Fig. 2, a), detected during sudden cooling after welding.
The release of dispersed particles of the metastable α-phase at the grain and subgrain boundaries is also recorded in the grain body both in the weld metal and in the HAZ.
At the same time, plates of the primary α-phase 1...3 μm thick are formed in the grains of the weld metal (see Fig. 3, b).
Outside of HAZ, grains do not have a substructure.
On the β-phase background, in the HAZ metal grains, as well as in the weld metal, needle-like precipitations of the α′-phase are observed, which are localized mainly near the boundaries and sub-boundaries, and accumulations of very dispersed point precipitates are also present in the HAZ grains.

The grain size distribution curve of the clay is shown in Fig. 1.
Fig. 1 Grain Size Distribution Curve of the Clay Mix Proportion.
Mix Proportions of Plastic Concrete Mixture Number Cement (kg/m3) Clay (kg/m3) Bentonite (kg/m3) Sand (kg/m3) Gravel (kg/m3) Water (kg/m3) PC1 120 160 50 810 710 350 PC2 120 190 50 760 680 400 PC3 120 270 50 720 640 400 PC4 120 310 50 710 620 390 PC5 120 330 50 690 610 400 PC6 120 350 50 685 600 395 PC7 120 370 50 670 590 400 PC8 120 380 50 660 590 400 Experimental Method.
Besides, as the content of clay is increasing, the number of clay particles in unit binding mortar increases.
Fig. 6 Effect of Clay Dosage on Elastic Modulus Conclusions In order to investigate the effect of clay dosage on mechanical properties of plastic concrete, a large number of experiments have been carried out in this study.

When nanoparticles are assembled into films or bulk-size structures, the high density of interfaces such as grain boundaries and steep composition and stress gradients, can give rise to unusual thermodynamic effects such as increase in bulk excess free energy and the interfacial free energy [6].
The assumptions for this size limit are as follows: i) the number of atoms N is such that the thermodynamic arguments remain valid; and ii) the surface of the particle may be characterized by its surface tension while deriving the free energy expression for the surface phase.
Effect of Particle Size on the Melting Point of Nanoparticles: The relationship between particle size and melting temperature has been discussed in our earlier work [8] and it is expressed as: ( ) ( ) 1/3 , , / . 1 / 2 m m l c m T T f B N T R γ γ α ∞ ∞ = + − =  −    (5) where ∞,mT the bulk melting temperature, f is is the geometrical factor depending on the shape of the particle, N is the number of atoms in the particle, and the term (fN2/3) is directly proportional to the ratio of surface to volume atoms.
(6) The size of particles affects the compositional surface segregations due to the change in surface tensions caused by the variations in the number of broken bonds.
It is evident that the surface segregation of Au in Au-Ti nanoparticles are larger when compared to that of the coarser grains (2R >100 nm).

Since the roughness coefficient is not affected only by just a factor, while there are a number of factors, therefore, establishment of a certain roughness coefficient with factors, is unscientific and imprecise, which requires us to establish a Kind of scientific and effective ways to predict.
At the same time, process which the water and sediment flow into the downstream has been changed by the regulation of reservoir and trigger a number of new phenomenon.
The factors affecting roughness coefficient includes Median grain size of bed load, sediment concentration, median grain size of suspended load, Froude number.

Engineering Information Number of floors 6-storey 4-storey, 2-storey Number of buildings 22 12 Underground storey Half-storey Half-storey Foundation depth 3.0 2.0 Form of the structure Frame Frame Size of column net 4×5 4×5 Single column load 1200~2100 600~1200 Form of the foundation Raft foundation Independent foundation Building types B C Foundation design level C C Classification of the building collapsible C C 1.
The effective reinforcement depth of dynamic compaction (m) [2] The single tamping energy（kN·m） Crushed gravel, sand and other coarse grained soil Silt, clay, loess and other fine-grained soil 1000 5.0～6.0 4.0～5.0 2000 6.0～7.0 5.0～6.0 3000 7.0～8.0 6.0～7.0 4000 8.0～9.0 7.0～8.0 5000 9.0～9.5 8.0～8.5 6000 9.5～10.0 8.5～9.0 8000 10.0～10.5 9.0～9.5 Note: The effective reinforce depth should be calculated starting from the initial tamping surface.
Then, a lime-soil compaction pile commitment to treat foundation area (calculated by S = 1.6m): The ground treatment area is 590 m2，the number of pile is: The depth of treatment is 8 m, unit price is 180 yuan / m3，The total cost is about 239 × 180 = 43 020 yuan. 4.2 The Cost of Soil Replacement Cushion Method The ground treatment area is 590 m2，the depth of treatment is 8 m, then the volume of the replacement filling is 590×3=1 770 m3.

The finite element method predicted the number of carbon fibre layers necessary to recover the initial mechanical resistance of the water steel pipe.
Table 2 presents a summary of the structural calculations made by finite elements, with the number of reinforcement carbon layers required, and the maximum stress.
The surface is prepared by mechanical stripping, using an abrasive jet of 50 µm grain ceramic beads.
The grains are projected at high velocity and cause a plastic deformation on the surface.
The type of the reinforcement and the number of layers applied is defined in the structural calculations and two different types of rehabilitation scenario are envisaged.

The elastic modulus of matrix polymer was controlled by changing the number of PFPs.
However, polycrystal NiMnGa cannot generate large magnetostrain due to the restriction from the surrounded grains [5].
The number of PFPs embedded in the silicone matrix was selected to be 0 (silicone only), 2, and 4.
Table 1 MVR start magnetization of each number of PFP.
The number of PFP 0 2 4 MVR start magnetization/kOe × 3.7 2.6 ×: no clear MVR observed Conclusions (1) The elastic modulus of silicone decreases with increasing the number of polystyrene form particles

In the present study the minimum and the maximum normal loads decrease with increasing number of cycles (Fig. 4a).
Minimum Maximum 715 725 735 745 755 765 775 785 0 10000 20000 30000 40000 50000 60000 Number of cycles Tangential load (N) ...
It reached a stabilized value after a certain number of cycles (approx. 20000 cycles).
In the present study the relative displacement amplitude decreased with increasing number of cycles up to 30000 cycles and then decreased (Fig. 5).
However it is not expected that it may have any influence on fatigue life; - the relative displacement amplitude substantially decreases with increasing number of cycles.

That is to say, for a specific reference wind velocity, the wind-blown sand flux will attain to an equilibrium state as the number of moving sand increases to a certain value such that the number of moving sand, sand transport rate, surface ejection flux as well as wind velocity profile keep stabilization [10-12].
As same as in [15], we take the number of entrained particles per unit area of bed per unit time to be proportional to the excess shear stress 2 ( ) a a c N C τ τ= − (1) where aτ is the short term shear stress at the bed, cτ is the critical fluid shear stress for entrainment, and C is a constant.
Trajectories of sand particles For simplicity, here we consider a steady wind blowing over an infinite plane, which is composed of spherical grains with identical diameter. pm is the mass of a sand particle, and pD its diameter.
In this paper, the splash function is chosen as [14]: 2 2 ( 0.56 ) ( ) 0.95 (1 exp( 2 ) xp[ ] (0.2 ) im r o im o im v v N v v e dv v − = × − − × − (3a) 0.3 ( ) 1.75 exp[ ] 0.25 s o im o im v N v v dv v = − (3b)� ( ) ( ) ( ) e o s o r o N v N v N v = + ������������������������������������������������������(3c) where ()roN v is the number of rebounding particles with velocity ov from a single impact of velocity imv , ()soN v is the number of particles ejected per impact and ()eoN v is the total number of particles leaving the bed with velocity ov subsequent to a single impact of velocity imv .
Numerical Results and Discussion Fig. 2 shows the evolution of the number of particles leaving the bed per square meter per 4 second due to both impacts and aerodynamic entrainment (the surface ejection flux).

There are two kinds of fracture morphology: development along the grain boundary, called intergranular crack; crack through the grain, said the transgranular crack; also mixed, as the main seam is intergranular type, seam or edge support are the transgranular crack type[1-7].
A large number of experimental studies have shown that microstructure of stress corrosion cracking is more important than of the chemical composition of steel.
The same ingredients reasonable heat treatment of steel, welded structure can be refined grain, getting the appropriate microstructure, to avoid the cracks welded structure, improve the welded joints and heat affected zone ductility and toughness, to increase resistance to stress corrosion capacity.