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Results obtained in planar grinding will be possible to apply also to other types of grinding for the same equivalent diameter De because the track size of abrasive grains, the number of active grains, thickness of abstracted layer, and depth of cut by one grain will be same.

[Å] (1) where n is a whole number = 1; λ - the wavelength = 1.54439 Å and θ-the calculated diffraction angle θ.
After TM processing a nanocrystalline (NC) microstructure has been obtained, consisting ofβ-Ti and α”-Ti grains, with acrystallite size close to 42 nm for β-Ti grains and 7 nm for α”-Ti grains.

However, for materials with a high atomic number, 3D visualization of fine structural features such as microcracks or pores by X-ray CT is still a challenge, mainly because of the larger X-ray absorption coefficient.
The microstructure of the cast Hadfield steel crossing is fully austenitic, with a grain size of ~150 mm.
Different lengths of the fatigue pre-crack at different locations as well as different crack extensions generated during the subsequent montonic loading may be caused by the microstructural factors such as crystallography of grains, grain boundaries and micropores, and also by the crack-tip mechanical environment, which is probably associated with the morphology and length of the crack at various locations along the crack front.

The average grain size, inside the NF´s, increased with the crystalline phase transformation from 10 to 24 nm for anatase-TiO2 and from 30 to 47 nm for rutile-TiO2, which were estimated by using the Scherrer-Debye equation.
Introduction The synthesis of new semiconductor materials in nanometric size has received much attention in recent years because of the industrial demands increase [1], the number of reports on these nanoparticles such as nanofibers (NF’s) has increased worldwide mainly on titanium dioxide [2].
However, it is not the only one; a greater number of their physical properties can be exploited by carrying out a more detailed and systematic characterization of the morphological and structural properties.
For AT = 500 °C a grain size of 13.65 nm is obtained, for a higher AT the grain size exceeds 14 nm; therefore, the CP transformation occurs (see Fig. 6a).
Fig. 7a displays a high-resolution TEM image showing the anatase CP grains in the M5-NF (AT = 500 °C).

Based on a large number of onsite structural surface investigations, acoustic measurements and field and laboratory tests, this paper discusses the related issues on division of rock mass structure using single lumpiness indicators and analyzes the impact of the structural body property and structural surface effect on the rock mass structure.
By comparing the different lithology test data of a number of hydropower projects, the following several aspects need further deepen: (1) The value range of hard rock strength is too large; this is easy to lead to the big difference of anti-deforming capability in the same kind of rock mass; Along with our country current dam height increase, the requirements for dam foundation rock mass will be stricter.
Physical and mechanical properties and deformation modulus of rock Type Representative rock Genetic feature Volumetric weight (g/cm3) Saturated compressive strength (MPa) Deformation modulus (GPa) Very hard rock gabbro, diorite, fine-grained granite, basalt, porphyrite plutonic intrusive or eject 2.60-3.10 150.0-240.0 33-65 2.72-2.92 165.4-169.8 34-38 gneiss, schist metamorphic 2.64-2.75 140.1-188.0 22-35 Hard rock sandstone, conglomerate shelf clastic deposit 2.65-2.70 60.0-80.0 20-14 limestone sedimentary 2.60-2.70 60.0-90.0 9-22 Medium hard rock coarse grained granite, pegmatite, porphyry shallow intrusive 2.57-2.61 59.2 4.4-23 hard shale sedimentary 2.50-2.65 30.0-70.0 0.81-7.14 schist, Slate regional metamorphism (light) 2.60-2.75 50.0 9-13 Soft-hard rock shale, sandy shale, shaly sandstone, feldspar sandstone sedimentary 2.34-2.57 2.40-2.60 13.7-38.8 0.51-3.20 argillaceous limestone shallow sea deposit 2.45-2.66 7.8-40.0 7.2 (2) Effect of rock
Even if they are cut by a large number of closed structural surfaces, the deformation modulus of rock mass is still higher than that of amygdaloidal basalt.

Carton black grain is so small that it just can be seen with the aid of microscope, so that the detected area of rubber’s surface is very small.
(b) Selecting the number of the frequency group, which is very important for histogram.
On the other hand, if the number is too big, the bins are too narrow, what may appear to be meaningful information really may be due to random variations that show up because of the small number of data points in a bin.
So the number of the frequency group is 8.
(d) Counting the number of the data points falling in various intervals (e) Drawing the shape.

By both SAXS and XRD particle size in the matrix can be calculated, proving small particles can be better combination of the matrix of PI, increasing the number of traps, more effectively cutting off charge corrosion and making corona resistance greater performance.
This article describes that PI/TiO2 nano-composite films are prepared in situ polymerization by changing the particle size to change the degree of integration of PI and nano-particles and increasing the number of traps, and particle size has an effect on the electrical properties of polyimide through the corona resistance research.
TABLE I THE TYPE AND NUMBER OF FILM Constituent Particle size 7wt% 15 wt % 25 wt % 20nm A1 A2 A3 50nm B1 B2 B3 Characterization of PI/TiO2 nanocomposite films.
Conclusions In this paper, the different particle size of PI/ TiO2 nanocomposite films were tested and analyzed following conclusions: By XRD spectrum we can judge that particles are Anatase TiO2, nanoparticles disperse in the polyimide and polyimide structure isn’t destroyed, after calculations and analysis grain size is consistent with actual size.
By the corona resistance time of the composite films, small nanoparticles have a longer corona resistance time, on the one hand increasing the surface area can better lateral release charge and make corona resistant of films strengthen, on the other hand a large number of traps generated trapped charge to reduce the chance of breakdown, Particles added increase thermal stability of the film to reduce the erosion of films.

The HIPed alloy shows uniform microstructure with low number of porosities.
The grain size of the as HIPed samples varied from 10 to 30 μm.
Vajpai, Kei Ameyama, A novel powder metallurgy processing approach to prepare fine-grained Ti-rich TiAl-based alloys from pre-alloyed powder, Interrmetallics, 2013, 42, 146–155
[15] Satoshi Emura, Aya Araoka, Masuo Hagiwara, B2 grain size refinement and its effect on room temperature tensile properties of a Ti–22Al–27Nb orthorhombic intermetallic alloy, Scripta Mater., 2003, 48, 629–634

Introduction N-lamina model of non-plug flow solid conveying in feeding section by single-screw extrusion molding is aiming at the state which materials just enters into the screw of a single screw extruder and is not compressed into solid plug, it takes powder materials or grain materials as the research object, and establishes the mathematical model and the physical model, all analyses and solutions are derived on the basis of non-plug solid conveying theory and virtual work principle of rigid body, etc [1, 2, 4].
(4) Conclusions when total number of laminae n takes 3 in n-lamina model When m=3 is put into equation (1), velocity of each lamina of materials, such as, can be explicitly solved, then the mean velocity of all laminae of materials,, can be gotten.
Then the roots of the unary cubic equation of coefficient k, such as,,are as follows Among the above three roots,,don’t meet the requirements, for they are two roots of imaginary number; may be the root which meets the requirements, for it is a real number.
Conclusions when total number of laminae n takes 4 in n-lamina model When m=4 is put into equation (1), velocity of each lamina of materials, such as, can be explicitly solved, then the mean velocity of all laminae of materials,, can be gotten.
Conclusions when total number of laminae n takes 5 or more in n-lamina model The general form of a polynomial equation of degree n is ，in the formula are constants.

When shifting from the base metal closer to the weld, grain size changes significantly.
Test results of steel grade 09G2S samples №№ series Sample type Max. tensile strength (σmax), [MPa] Fatigue stress range (Aσ), [MPa] Number of cycles (N) 1.
Test results of steel grade 17G1S-U samples №№ series Sample type Max. tensile strength (σmax), [MPa] Fatigue stress range (Aσ), [MPa] Number of cycles (N) 1.
B – nonwelded samples 360 36 368210 11. 360 28 527300 12. 270 36 481480 13. 270 20 1265300 14. 270 20 637800 Determining residual operation time is possible if the number of load cycles and their amount are known (Na).
On the supposition of probable operation conditions of the tested welded construction (σmax and Aσ), one can determine the number of loads at failure (Nf).