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D-gun coating, one of the thermal spraying processes, is increasingly popular owing to its versatility in spraying a large number of materials.
The orthogonal array chosen was L27 (33) which have 27 rows corresponding to the number of tests (26 degree of freedom) with 13 columns.
The grain size has a reversed trend compared to velocity, as the grit size increases the erosion rate is significantly reduced.
An optimum parameter combination for high erosion resistance are the medium velocity (40m/s), medium angle of impact (45o) and medium grain size (180μm) Similarly medium velocity (40m/s), minimum angle of impact (30o) and lowerm grit size (120μm) yields maximum erosion rate indicating low resistance.
Number 2 .

Furthermore, modifying some parameters such as a high number of cycles, high extrusion pressure, high abrasive concentration and low abrasive grain size, improved the precision of surface polishing [6-7].
The active grain density on a medium's surface was also determined by stochastic simulation [13].
Figure 8 presents the effects of number of working cycles on surface roughness in the different passageways.
According to Fig. 8 regardless what passageways were used, surface roughness decreased with increase in number of working cycles.

A large number of experiments show that: in the compaction test, moisture content has significant effect on the material dry bulk density.
For harmonic system composed of a number of natural frequency, each has its own law of vibration frequency, when using the natural frequency of the same frequency to trigger the system, high amplitude resonance phenomenon can be produced.
Where Shear strength is closely related to material properties, for clay, due to the particles is small, interaction between soil - water system and cementing material form grain structure, the small influence of friction angle can be ignored,the shear strength is mainly produced by the cohesion.
Sand is single grain structure and cohesion in the process of compaction is small which can be ignored.
Table 1 Aggregate quality parameters Material Name crushed aggregate 9.5~19mm crushed aggregate 19~37.5mm crushed aggregate 4.75~9.5mm Chippings 0~4.75mm stacking density （g/cm3） 1.60 1.38 1.56 1.623 Apparent density （g/cm3） 2.652 2.777 2.757 2.631 mud content （%） 0.2 0.3 0.6 3.3 crushing value （%） 11.8 / / / acicular content（%） 4.2 3.9 3.2 / Table 2 Mixture Gradation Composition Number 1 2 3 4 5 6 7 8 9 Mesh size（mm） 37.5 31.5 26.5 16.0 9.5 4.75 1.18 0.6 0.075 throughput rate /% 1# 100 97.2 78.5 58.3 38.5 24.8 14.6 9.4 1.1 2# 100 97.1 78.3 57.9 37.9 25.0 15.2 10.1 1.5 Mean value 100 97.2 78.4 58.1 38.2 24.9 14.9 9.8 1.3 3.2 Test schemes and results The tests are using two schemes, one is in different moisture content, the dry density of mixture was measured by using heavy compaction; the other is in a different vibration frequencies, different vibration times and different moisture content, the dry density of mixture was measured by using vibration compactor.

Presented research results allow to determine the relationship between the structure, wear resistance, and the specific module responsible for the number, type and position of cathodes used in the constitution of the tested coatings.
The modules that are responsible for the position, number and type of cathodes in the chamber, after the appropriate combination, allow to obtain very good results when it comes to the structure, mechanical and functional properties of the coatings produced.
The areas of coatings dimensioned 5´5 µm were scanned during the measurement, and N=512×512 measurements of specimen height were made, where numbers refer, respectively, to the number of scanned lines and measuring points for each of them.
However, the image of the surface of the breakthroughs of the AlCrSiN 2 coating confirms the existence of a fine-grained nanocrystalline structure and diversified grain size (Fig. 10).
Appropriate selection of the module, position, number and type of cathodes, gives the possibility to obtain very good results about to the structure, mechanical and functional properties of the coatings produced.

Wetlands play a number of roles in the environment, which are also considered the most biologically diverse of all ecosystems.
The change pattern of wetland resources Amplitude of the dynamic changes of wetland resources available wetland changes, characterized by speed and changes in the number of regional differences, the degree of change of wetlands can be quantitatively describe the speed of change in wetlands, its relatively wetland resources change area Different and forecast the future trends of the wetlands have a positive meaning.
The wetlands dynamic calculation of the rate of change of a single wet Land resources can express the number of changes of some type in the area some time within the formula is expressed as: M = (Kb-Ka) / Ka * T Where Ka, Kb, respectively, for the study of the number of beginning and end of a particular type; T study period.
Spatial and temporal variations in sediment grain size in tidal wetlands, Yangtze Delta: On the role of physical and biotic controls Estuarine, Coastal and Shelf Science,2008, 77,pp.657-671

Taguchi technique was employed to get optimum number of experiments for turning white cast iron after the cryogenic treatment and before cryogenic treatment.
M N Islam [6] concluded that precipitation and distribution of η phase after cryogenic treatment improves wear resistance and slight increase in grain size contributes to toughness.
Seah et al [8] implemented the cryogenic treatment on cobalt-bonded tungsten carbide (Co-WC) and reported superior behaviour because the number of η-phase particles has been increased.
Taguchi Design of experiments was used to design the optimum number of experiments.
The total number of experiments conducted were 36.

A number of MWNTs were observed pulled out from the alumina matrix.
The alumina grains became more rounded and more pores (indicated by arrows) could be found in Fig.3B.
On the fracture surface, MWNTs were observed pulled out from the matrix, but their number was relatively less compared to the number of MWNTs in Fig.2B.
This lower density and fewer numbers of pulled-out MWNTs caused the catastrophic decrease in bending strength.

On the basis of numerical methods, the mutually dependent parameters or variables are solved in the finite number of the nodal points of the discretization mesh in calculated domain.
The numerical methods enable us to find the solution of the physical variable for the specific number of discrete sites (nodes) in relation to the selected differential mesh (finite element mesh) and it is in connection with the whole domain and surface part of the created geometrical model.
The basic principle of FEM is based on the fact that the arbitrary continuous variable (e.g. temperature, velocity, etc.) is substituted by discrete model which is defined as a set of continuous functions (polynomials) with reference to finite number of sub-domains (elements).
The searched functions are approximated by polynomials in the boundaries of the each one sub-domain in such a way that the coefficients of the approximating polynomials are expressed by the values of searched function in the finite number of the nodal element points.
After the evaluation of the nine samples under the different stresses on the basis of the temperature and time effect, it can be concluded that stainless steel (designated as STN 17 248) is able to operate for short time (for ~1 hour) at 900°C, but when the holding time is increased at the same temperature, the grain coarsening is observed and it can have negative influence on corrosion resistance as well as mechanical properties of the tested material.

Title of Publication (to be inserted by the publisher) Scaffold Fabrication The polymers foams were impregnated with the following suspension: 88,4 g of TiO2 powder (Kronos TiO2 No 1171, Kronos Titan GmbH, Leverkusen, Germany) with a median grain size of 0.3 µm mixed with 25,8 g deionised water.
Results Foam structure The macrostructure of the sintered scaffolds is characterised by a fully open structure for both ppi-numbers, although a very low number of closed cells is always present.
The tortuosity, which was measured in the mercury intrusion meter, was several factors higher for 60 ppi scaffolds compared to 45 ppi and therefore do also explain the lower permeability for higher ppi-numbers.
The pore size is easily adjusted by using polymer foams with different ppi-numbers.

The titanium substrates were placed in the reactor so that sample number 1 was located in the middle of the cumulative jet, samples number 2 and number 3 on the periphery at equal distance from the center.
The average crystallite size for sample number 1 estimated by Scherrer formula is: · crystallites TiC – 33 nm., · crystallites of HCP titanium – 16 nm., · crystallites of BCC titanium – 7 nm.
This indicates the presence of the transition zones where titanium grains of substrate are mixed with the coating material.