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Although many researchers have investigated the mechanism of fracture propagation in rock with numerical methods and laboratory experiment [1-5], it is well known that rock mass is composed of various of grains, microcracks and holes, which is regarded as the most complicated material in nature for the tectonic evolution of the earth.
It was observed that subjected to uniaxial compressive loading, a large number of isolated microfractures inducted from the heterogeneity of rock and some of them from the tip of pre-existing flaw, and it is difficult to predict where the microfractures initiate from the dispersion characteristic of AE events in this stage (Fig. 4a,5a).
The microfractures begin to localize in this stage, and the number of microfractures sites (AE events) indicates that microfractures interaction can cause microfractures to propagate and coalesce, as a consequence, the so called wing crack is formed.

A number of surface modification techniques, for example, electrochemical plating, conversion coating, anodizing, gas-phase deposition process and organic coating, have been used to improve its wear and corrosion resistance.
For the alloy AlFeCuCoNiCrTi1.5 in the experiments, its mixing entropy DSm=Rln(n)=Rln7=1.95R, (R: gas constant; n: the number of elements), is much higher than the formation entropy of intermetallic compounds or ordered phases.
The reason is that, under the effect of rapid heating and rapid cooling of the laser beam, the microstructure became very fine and is benefical to improve the microhardness of the HEA coating due to the fine-grained strengthening effect.

Introduction Dry bulk carriers are usually used for the transportation of considerable volumes of homogenous cargo: chemical products (phosphates, fertilizers), cement, iron ore, coal, agro products (grain, beans) [1].
It should be noted that whilst the terminals in Japan and South Korea are largely import terminals there are a number of export coal terminals in China.
The smallest vessel is taken as 20 000 DWT for the following reasons: - there are only 5.8% of vessels below 20 000 DWT in the world fleet; - there are a significant number of terminals in Asian region which can accommodate vessels up to 20 000 DWT; - the trend is for future vessels to be larger; - only 1% of calls over the last two year at Vostochny Port were by dry bulk carriers less than 10 000 DWT whereas 7.5% of calls were by 10 000 - 15 000 DWT vessels and 29.5% of all calls were by vessels of 20 000 - 25 000 DWT.

For a laminar particle moving Reynolds number is sub-unitary.
The dispersed material can determine a significant diminution of grain size if it intensifies the nucleation process.
Although the gravitational casting of mixtures has some advantages should not be neglected a number of specific problems related especially to incorporation of additional material in the metallic molten or settling tendency of particles.

Because of these advantages, cold spray technology has become a powerful new tool to enhance the useful life of an almost unlimited number of metallic components with profound benefits not only for availability and cost savings, but also for sustainable manufacturing efforts and minimizing the impact of industrial processes on the environment.
CS deposited metals, using high-pressure and generally helium or nitrogen, can now consistently achieve low porosity (< 1%), exceptional mechanical strength (>40 ksi) and adhesion (>10 ksi), and produce wrought type microstructures with low or sub-micron sized grains (ref.
Therefore, due to its numerous advantages, cold spray technology has become a powerful new tool to enhance the useful life of an almost unlimited number of metallic components with profound benefits not only for enhanced availability and cost savings, but also for sustainable manufacturing efforts and minimizing the impact of industrial processes on the environment, as there are no toxic fumes or other harmful emissions from cold spray.

The equation for water quality change is: Equation for riverway: (1) Equation for riverway junction: (2) Where: Q and Z are respectively flow and water level; A is section area of the riverway; Ex is a vertical diffusion factor; C is the concentration of the substance transported by water flow; Ω is the water surface area of riverway junction (node); j is node number; l is the number of riverway connected with node j; Sc is an attenuation item related to the concentration of the transported substance, with Sc=kdAC; kd is the attenuation factor; S is an external source or sink.
Langmuir adsorption model simulates the adsorption-desorption kinetics process, according to the median grain size measurement and Huang’s research, after the repeated debug, determine the cadmium absorption rate factor is 0.000045/ (ppm.s), and the desorption rate factor is 0.0000015/s.

Disintegrators present a group of milling machines operating at high collision speeds (up to 200–400 m/s) and they have a number of advantages over other mills [8]: (a) they are compact and allow grinding materials with a very wide hardness range, (b) they have very low contamination of ground products, (c) the consumption of energy at the same amount of new surface units of materials is twice lower than by vibration mills and ten times lower than by ball mills and (d) during the simultaneous grinding of different materials, an ideal mixing of all materials takes place.
Niobium slag: a – initial pieces of slag, b – cross-section of piece with Nb grains.
Direct and selective mode Separative mode Number of rows 2 3 4 5 2-5 Productivity [ton/h] 1.9 0.9 0.7 0.5 0.25 0.1 Specific energy of treatment [kWh/ton] 3.9 5.9 7.5 8.8 20 50 Particles size [μm] depends on material properties <250 <100 Cement testing.

Some recrystallized grains are elongated in the rolling direction.
For the anodized one, a smooth anodic coating with numbers of pits had formed upon the surface (Fig. 3b).
After anodizing, there are numbers of pits on the oxidized surface, which caused stress concentration as defects.

The average spatial distribution of the charged ions is also taken to follow the Boltzmann distribution, (1.3) r is the number density of the ions and r0 is the corresponding density in the bulk solution. z is the valency, y is the electrostatic potential and e is the electronic charge.
The Debye screening length (k ) is defined as (1.5) where NA is the Avogadro’s number and C is the ionic strength.
Wade, Brownian Dynamics Simulation of Protein Solutions: Structural and Dynamical Properties, Biophysical Journal Volume, 99, 3782–3791, December 2010 [13] Xuan-YuMeng, Yu Xu, Hong-Xing Zhang, Mihaly Mezei and Meng Cui, Predicting Protein Interactions by Brownian Dynamics Simulations, Journal of Biomedicine and Biotechnology, volume 2012, page 1-11, 2012 [14] Po-Hsien Lee, Volkhard Helms, and Tihamér Geyer, Coarse-grained Brownian dynamics simulations of protein translocation through nanopores, The Journal of Chemical Physics, 137, 145105, 2012 [15] David R.

Particular attention has been given to production of material with minimal number of pores in a ceramic layer.
Microhardness depends significantly on the ceramic composition and reaches its maximum at 6-10% AlN, which is associated with grinding of grains and reduction in porosity of ceramics.
Mechanic properties of steel 3310H σb, MPa σ0, MPa δ5,% Ψ,% KCU, J/cm2 930 735 10 45 78 The tests of plates of HGC-ceramics with Ti-TiCrN-TiCrAlSiN were carried out in machining of crown end of work pieces for gear wheels made of steel 3310H on a lathe of model 16K40.After roughing and thermal machining, work pieces for gear wheels made of steel 3310H were cemented along the entire height of gear crown (number of teeth of wheel crown z = 75, module m = 10) to depth h = 2.05-2.4 mm up to hardness HRC3>56 when hardness of base metal HRC> 30 (Fig. 2).