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While well pumping tests are widely used to estimate K values, many limitations such as limited number of wells, and cost of conducting a pumping test can affect the quality of representative K values determined for an aquifer.
The Formation is a lower Cretaceous of the Khorat group which is composed of medium to coarse-grained sandstone, conglomeratic sandstone and conglomerate.
The K value of a fractured aquifer is normally and spatially a random number.
The empirical probability [6], Fs, was calculated by Fs = m/(n+1), m is rank of data, and n is number of data.

Investigation of the process of electric arc synthesis and thermal centrifugal dispersion of KV for the implementation of the technology for the manufacture of powders, with a main fraction size of 0.5-8 microns, a spheroidal grain shape, suitable for the manufacture of high-quality metal-cutting tools and a raw material basis for additive technologies for the production of complex-shaped products of a wide range. 2.
Organization of production of powder raw materials for additive and instrumental industries Current State of Technology for the Production of Dispersed Powders From 1973 to 2017, the properties and phase transformations of the W-C system, studies of the structure and properties of individual phases (W2C; WC; WCi-x), the synthesis of carbides, and the formation of coatings were devoted to over 600 works The composition and properties of the powder depend on the method of its preparation, each of which has a number of disadvantages (table 1.) [1 - 5].
The particle size depends on a number of factors: the diameter of the blanks, the speed of rotation and feed of the rods, the intensity of the heat flux of the plasma arc, the presence and nature of the gas atmosphere in the reactor.
Modeling, 1999, volume 11, number 2, 55–64)

A number of thermoplastic or thermo-type polymers are used in various forms, such as liquid resins, powder and latex redispersibile, water soluble polymers or copolymers to change concrete and mortar [1].
But the builders are skeptical about use of these types of materials either the small number of research carried out on these materials or due to their higher costs.
As the water penetrates the the matrix and reach the surface of unhydrated cement particle, new reactions take been, new products appear which cause cracking in polymer and etringit matrix and the hydration of mineralogical compounds with hydraulic activity from cement grain (calcium silicates) is carried out.
In these mixtures, it can also be seen a large number of air voids.

Probably, the effect of dislocations, which form subgrain boundaries, on dislocation nucleation in Mo single crystal under the indenter is insignificant as the size of even the smallest grains (200 µm) is considerably larger than the contact size.
Values of power law exponent m are 1 for flat cylinders, 1.5 for spheres and 2 for cones. 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0 2 4 6 8 10 Number of events Critical load Pc, mN (001) Mo a 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0 2 4 6 8 10 12 14 16 Number of events Critical load Pc, mN (001) Mo - Ir b Fig. 3.
Besides, because of the solid solution strengthening the stress necessary to activate the Load P h а R hс Zone of the highest shear stress multiplication source (for example, the FranK - Read source) of the same configuration is higher in the Mo - Ir single crystal. 0 5 10 15 20 25 0 5 10 15 20 25 30 Number of events Critical shear stress τcrit, GPa Mo Mo - 1.5Ir Fig. 6.

Mn is added to increase the strength of the Al-Mg-Si alloy as well as to control the grain size [4,5].
In addition the number of deep tips and crevices decreases for the finer polished surface Fig. 1 a) line scans of a surface polished with 0.25µm diamond paste and polished with SiC paper grit 4000 b) Number of tips and crevices measured on line scans of 500µm length for a surface grinded with SiC paper grit 4000 and a surface polished with diamond paste 0.25µm.From the data given in Fig. 1 b) crevice distance can be estimated which can be related to possible initiation site density.
Despite the reduced number of crevices in the measured area the PP is astoundingly low, namely -578mV ±73mV.

Literature survey highlights the selection of proper optimal parameter for obtaining higher material removal rate and lower surface roughness in WEDM due to the large number of process variables. 3.0 Material and Methods Tungsten Carbide composite with cobalt binder (WC-20%Co) was selected as work material.
Composition and Properties of WC-20%Co Av.grain Size (µ) Density (g/c.c) Young’s modulus (GPa) Hardness (H R.A) Thermal expansion (K-¹) 0.9 13.55 490 85.5 6.4 x 10-6 Table 2.
For the HB and LB, the definitions of the loss function (L) for machining performance results (MRR, surface roughness) of n repeated number are, Where YMRR and YSF are the response for material removal rate and surface finish respectively and n denotes the number of experiments.

Roundness of workpiece has direct relation with rotate accuracy of workpiece Fig. 2 Structure sketch of machine tool Fig. 1 Sketch map of workpiece Headstock Fig. 4 Distribution of dimensions 25.110 25.120 25.130 25.140 25.150 25.160 25.170 25.180 25.190 25.200 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 (number) ( m m ) left end right end and wheel.
Grinding number [piece] Cycle [s] Roundness [µm] Straightness [µm] Waviness [µm] Roughness Rz [µm] 1 65 0.27 0.65 0.3 0.87 5 40 0.4 0.77 0.6 0.9 10 36 0.35 0.82 0.45 0.95 20 29 0.54 0.96 0.68 1.1 35 28 0.47 1.1 0.59 1.2 50 28 0.43 1.4 0.5 1.3 It can be seen from Table 3 that grinding cycle became shorter gradually then stable after twenty and straightness and roughness deteriorated along with number increasing, while the changes of 0ame or Items Specification or Parameters Wheel type 1A8 20×33×M8 Rotate speed of the wheel ns = 30000～45000 r/min, ds =φ20mm Workpiece and its surface to be ground Inner hole of the piston, dw=φ25.4mm Workpiece material NiCrMo alloy, HRC45～55 Grinding allowance ap = 0.1～0.3 mm Wheel dressing Diamond rotary wheel, ad = 0.005~0.02 mm Cooling mode Water cooling Parameters Machines Cycle [sec] Roundness [µm] Straightness [µm] Waviness [µm] Roughness[µm] Dressing interval [piece] TOYO
However, grinding force fell soon then stable after ten workpieces and roughness value became bigger gradually because the wheel was sharper and sharper along with grain fracture and detachment.

.%) 10.56 7.25 18.24 42.18 21.74 Microstructural characterization The metallographic samples extracted from AlCrNiCuMn ingots were first polishing with SiC wet metallographic papers (P60-P1200), then mirror polished with Al2O3 suspensions (1 μm and 0.02 μm grain sizes).
SEM analysis under atomic number contrast (elemental map) reveals a different chemical composition for the dendrites and biphasic interdendritic matrix.
SEM observations under atomic number contrast reveal a different chemical composition for the lamellae, with a higher concentration of Cr in a dendritic (DR) domain, is forming a phase of Cr-Mn.
Acknowledgments This work was supported by a grant of the Romanian National Authority for Scientific Research, CNCS-UEFISCDI project number PN-II-PT-PCCA-2013-4-1048.

On the basis of the remarkable physical properties and the versatile applications of the ZnO material, a number of 1D ZnO nanomaterials with different morphologies such as wires [5], rods [6], needles [7], columns [8], towers [9], belts [10], nails [11], helices [12], combs [13], and Tetrapod [14] have been successfully synthesized.
The FTIR spectrum has been recorded using a SHIMADZU FTIR – 8400S spectrometer in the wave number range of 400 - 4000 cm-1.
The grain size of as prepared nano particles is found to be 41 nm.
Zinc oxide, with a high surface reactivity owing to a large number of native defect sites arising has emerged to be an efficient photocatalyst material compared to other metal oxides [25-27].

The average grain size of the material was 40 7 microns.
This behavior may be ascribed either to the formation of phosphide precipitates in lower number densities or to their near absence.
Differences in diffusion behavior and the number density of TiC precipitates formed due to the variation in Ti concentration cause significant changes in the swelling behavior.
By systematically varying the welding parameters such as peak current, background current, pulse width, pulse rate, welding speed, arc gap, electrode tilt, gas flow rate, and total time of welding during the trials, the number of cracks and their dimensions were gradually brought down and finally completely eliminated [11].