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The larger the number and size of M-A island is, the lower the toughness is.
The lower the cooling rate, the larger the grain size and the higher the volume fraction of M-A island formed in the low temperature zone.
When the cooling rate is less than 5 ℃ /s, the main microstructure of the steel is polygonal ferrite and a small amount of pearlite formed along the grain boundary.
Granular bainite replaces ferrite as the main microstructure, and the microstructure becomes more uniform and smaller, and very small amounts of pearlite still exists along the grain boundary.
Some lath bainite formed in steel A, and the grains are refined.

The difficulty of developing a mathematical model based on the macrostructure of fiber concrete is the complication of accounting for the large number of parameters of the dispersiony reinforcement, properties of raw materials (binder materials, aggregates, fiber) and obtained composite material.
In the experimental part introduced a number of restrictions: – dispersion medium selected structure of heavy concrete class B25, B30 and B35 produced from Portland cement CEM 42,5 N, large granite and fine quartz aggregates; – concrete mix should possess characteristics that allow its use for the manufacture of monolithic and maker fiber reinforced constructions; – in the studies used fibers only durable alkali-resistant materials: steel, basalt and polypropylene; – geometric properties of fibers of different materials must match produced in commercial quantities and on the market of the Sverdlovsk region; – the investigated parameters – only the direct measured characteristics of the original substances obtained composite material: geometrical, deformation-strength and technology.
Many researchers point to the need for selecting the fiber length dispersiony reinforcement depending on grain-size concrete aggregate, because of the arrangement of fibers in perpendicular to the load application direction [3, 5].
For hard fibers (steel) an increase in fiber diameter leads to an additional splitting of the grains of coarse aggregate that at a constant ratio of coarse aggregate and mortar matrix leads to an increase in the number of macropores in the structure of concrete [1, 3].
When using a flexible basalt or polypropylene fibers, the variation of the fiber diameter at constant mass (or volume) leads to a change in the number of fibers (dispersion).

The number of electrons was taken according to the total electrode reaction, yBi3+ + wSr2+ + zCa 2+ + xCu 2+ + (3y + 2w +2z +2x)e �BiySrwCazCux Fig. 2 shows the changes of XRD patterns in samples obtained from different electrodeposition times.
Evaluation of the degree of c-axis alignment in the several samples was based upon the X-ray diffraction rocking curves FWHM and calculation of the fraction of random oriented grains using the relation [4], )0010()008()115((113))200( (115))113( IIIII I I ++++ + =� (1) where I(hkl) represents the intensity of the peak with the (hkl) crystallographic orientation.
SEM analysis of the films, Fig. 2b, reveal that the film is covered with a rough layer of grains with a variety of shapes and sizes, but underneath it a plate-like structure is observed, Fig. 2c.
On comparing the degree of the c-axis alignment, the results also reveal that FWHM and � values are almost independent of the number of cycles (for n=30, FWHM=4.03°; �=0.049; for n=50, FWHM=4.65°; �=0.056).
a) Fig.3- a) XRD patterns of annealed films obtained by pulsed potential cycles (n= number of cycles); b) SEM of annealed BSCCO films formed under pulse potential conditions (n=50); c) SEM of the film underneath.

Through counting the numbers, we will be amazed that these people needs around 0.1 billion department units.
The growing number of the aged in the city has burdened the nation old-age pension.
ii.agricultural products In the process of urbanization, there are a great number of farmers entering into downtown, abandoning their ground.
Because of the two reasons above, the output of grains and some agricultural production decreases quickly.
On the contrary, the number of consumers in the city is rising perpendicularly, who eat the vegetables and eggs supplied by the rural area.

And, coarse grain off easy but fine not easy shedding, conduce the poor selectivity of flotation column at past, and the small particle size application.
(1) This machine can improve the overall apparent inflatable rate of flotation column without increasing single generators apparent inflatable rate, thus increased the number of bubbles without increasing the bubble diameter
(2) Avoided the station of particles fall off from bubbles when the particle large and the conveying distance long, thus increasing the adaptability of the flotation column for the material grain size and expanding the upper and lower limits of processing material particle size
It overcomes the shortcomings of the common flotation column bubble, bubble number and the height of column mutual restraint.
It reduced the height and increased the bubble number without increased the bubble diameter

A number of mg-alloys have been tested since (both in-vivo and in-vitro) to optimize their biodegradation rare and corrosion properties.
Introduction Bone defects and associated health problems affect a significant number of human population throughout the world.
Therefore, alloying additions have been required to improve the mechanical properties by strengthening through solid-solution, precipitation or grain-refinement.
The solubility of Ca in Mg is about 1.34 wt. %, and under the equilibrium conditions, Ca contributes to solid solution strengthening, grain boundary strengthening, precipitation and grain-refinement [28].
A number of composite samples with varying HA concentrations were compared through immersion tests in the simulated body fluid (SBF) as shown in Table 4.

By increasing the number of nuclei, very fine and uniform globular microstructures can be obtained, resulting in an increase of mechanical properties.
The most important things for the commercialization of the rheocasting process are to improve the quality of metallic slurry, such as obtaining fine and uniform grain size, to shorten the process time for manufacturing the metallic slurry leading to an increase of productivity, to decrease the production cost, and to improve the mechanical properties.
The H-NCM(Hong-NanoCasting Method) System If the nucleation density increases in the beginning stage of solidification, the primary α phase can easily grow into the globular shape with much finer grain size even under much faster cooling rates.
If we can increase the number of the nucleation density to N=15, such as for H-NCM, very fine and uniform globular microstructures compared to the case of N=1 will be obtained.
If we can increase the number of nucleation density up to N=1000, much finer globular microstructures, such as below 10 �, will be obtained, even at much faster cooling rates of 5°C/sec~10°C/sec.

The Use of Power Monitoring and Electron Microscopy in Evaluating the Performance and Fracture Characteristics of Abrasive Grains Jeffrey Badger1,3,a*, Radovan Drazumeric2,3,b and Peter Krajnik2,3,c 1The Grinding Doc, 82 Jane Street, #5B, New York, NY 10014, USA 2Univerisity of Ljubljana, Faculty of Mechanical Engineering, Askerceva 6, Ljubljana, Slovenia 3The International Grinding Institute, 127 W. 83rd St., #424, New York, NY 10024, USA ajeffrey.badger@grindinginstitute.com, bradovan.drazumeric@fs.uni-lj.si, cpeter.krajnik@fs.uni-lj.si Keywords: Abrasives, sintered abrasive, engineered-shape abrasive, fracture, chip-formation, electron microscopy.
The use of electron microscopy and power-monitoring during grinding was investigated in terms of evaluating the fracture and wear characteristics and chip-formation mechanisms of abrasive grains and bond formulations.
If that wheel is grinding at a wheel speed of vs=50 m/s and has a width of bs=25 mm, we can use the equation for the number of abrasive interactions per second, Na, given as: Na = vs · bs · C (1) to obtain Na=11.6 million abrasive contacts per second.
However, if the Aggressiveness Number, Aggrg, is chosen correctly, the power rise will not be rapid and drastic, as show in Figure 3.

Figure 3 shows nano-spherical grains in the case of pure copper oxide.
When the doping is present; there is a clear change in the shape of the grains after the addition of Ag.
Moreover, the presence of large pores and in greater number with an increase in the doping rate confirms that Ag gives a more porous surface.
It was also observed that there was an increase in the number and in the average size of pores.
Pore number increases with the increase of the doping rate, which gave a very high efficiency and more catalytic surfaces.

Cell number and cell activity (WST) were tested over a period of 3 to 13 days.
Infiltration of farringtonite with PLGA approximately doubled cell number compared to pure farringtonite.
As expected, pore diameter decreased with ppi number.
From SEM images (Fig. 3) a changed grain morphology can be observed at the surface of the struts.
In farringtonite foams microstructure is fine grained with some intergranular porosity.