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The results establish this technology for analysis of nano-scale niobium carbo-nitride precipitates Introduction Niobium is regarded as the most effective microalloying element, providing simultanuously high strength and toughness by grain refinement during thermomechanical processing of flat and long products.
The lightly spotted Debye-Scherrer-rings indicate a grain size above 30 µm of the as cast material.
This region shows the interesting peaks of the precipitates numbered from 1 – 9.
The numbers of peaks correspond to the phases given in Table 2 When compared to model alloy H0, HSLA-HD shows multiple variations in NbxCy-precipitate phases as Nb2C and Nb6C5.

Stable crack propagation and grain bridging were observed in pure mode I test of both specimens.
The decrease of effect of grain bridging also decreased the fracture toughness.
AE event number of notched specimen increased under near-mode I loading
However, the number of AE events decreased under near-mode II loading.
The relationship between the ratio of mode and AE event number.

There was difference in the number of bands and polymorphic bands between different primers.
As can be seen from table 5 and fig 3, the number of bands which were amplified from 20 primers range from 4 ~ 9, a total of 122 bands, an average 6.1 bands of each primer.
The number of amplified polymorphic bands range from 2 ~ 8, a total of 71 bands, an average 3.55 polymorphic bands of each primer.
There was one castor germplasm in1, 2, 3 groups, named “large grain King”, “North 1” and “FenBi 7th” respectively.
As can be known from clustering analysis, the germplasm distinction of 37 castor is small, which may be caused by the following factors: firstly, the number of the castor bean varieties is not abundant to supply enough gene type; secondly, screening is not comprehensive enough by limited random primers; thirdly, number of the castor genotype is small.

Sand, which consists of many small grains, can be used effectively in a site.
In this case, the maximum number of cannonballs fired should be small.

Relative errors are found to be below 12 % when the number of measurements is of order 400-1000.
The number of independent metric parameters that can be determined from 2D sections is limited to three.
A small amount of (nanosized) interstitial pores between the ceramic grains may be present as well, but with respect to the high sintering temperature these pores will of course not contribute any significant porosity.
It has been found that relative errors are below 12 % when the number of measurements is of order 400-1000.
[10] ASTM E 112-96, Standard Test Methods for Determining Average Grain Size, American Society for Testing of Materials, West Conshohocken, PA, 1996

The approach of specified number of cycles is applied to determine the threshold stress intensity factor range DKth, and an EVO scanning electron microscope is applied to investigate the fracture surface morphologies of specimens of GH4133B superalloy.
The Paris formula is written as (1) where, a is the length of fatigue crack, N is the number of cycles, and parameter C and D are two material constants.
Due to the stress concentration effect, the nucleation microviods grow up rapidly and coalesce with each other, and very high levels of stress at the crack tip induce a large strain gradient near the grain boundary.
The grain boundaries can not coordinate the heterogeneous deformations among grains, resulting in grain boundary cracking.
Furthermore, there exist a large number of ductile dimples in the rapid crack growth region, and many fracture crystal planes and secondary cracks at the bottom of dimples can be observed, as shown in Fig. 3(d).

After crushing, grinding and screening, the grain size of minerals used in flotation tests were -0. 106 mm +0. 044 mm.
Through spectral analysis, X-ray diffraction analysis, chemical multi-element analysis and phase analysis, the main chemical compositions of the ore were MgO 42.81 percent, SiO2 2.33 percent, CaO 4.91 percent ; the grain size was coarse; the main gangues were quartz and dolomite; and other impurities were very little.
The chemical elements were analyzed by XPS ,and the grain size of minerals were -5μm.The results were shown in table 1 and Fig. 7.
The calculation results of the coulomb force and bonding intensity of Mn+-O2- bond showed that the breakage of Mg—O bond and Ca—O bond often occur in the magnesite and dolomite crystal structures which cause a large number of metallic cations on the crystal surface.
Effects of grain size and regulators on separation of quartz from magnesite.

According to Fig.2, since the increase of porosity increases the number of places where [high] stress intensity originates, part of the improvement of strength and hardness of hot-press specimens (Table 1) can be attributed to the decrease of fracture origination spots, i.e., the decrease in number and size of pores.
In addition, columnar grains appeared in the hot-press sintered specimen (Fig.2 (b)).
Fig.2 Surface morphology of FM and FMHP observed by SEM (Arrows are pore and columnar grain) Table 2� Porosity and diameter of pore of Material SN, FMa, SNHP and FMHP.
SN Material FMa Porosity, � 1.20 1.43 0.02 0.17 SNHP FMHP Diameter of blow hole, /� m 0.28 0.34 0.06 0.10 d 0 0.5 1 1.5 2 2.5 3 Grain Size, Material SN SNHP FMa FMHP D/� m 0 5 10 15 Aspect ratio Material SN SNHP FMa FMHP Fig.3 Grain size and aspect ratio of SN, FMa, SNHP and FMHP.
Of course, larger numbers of micro-oil droplets stayed near the pores.

In summary the wear testing conditions were as follows: · counter wear surface consisted of a vitrified corundum wheel of industrial standard; · speed of wear test, 30 m/s; · a set “depth-of-cut” of 0.3 mm as set for each traverse of the 50 mm wide wheel and a nominal 100 cuts were used, although for poor quality tools, this number was reduced; · loading on the tool was measured using a load cell mounted on the sample holder; · abrasive wear rate was calculated as the weight loss of the tool per cubic metre of wheel cut.
Wear data for diamond composite coated WC-Co substrates Sample ID Number of cuts Wear distance (m) Wear rate1(g/m3) 1-2 100 3394 7.1 2-3 100 4176 7.3 2-4 100 3399 6.0 3-1 10 379 14589 3-4 4 152 7816 3-8 2 76 7823 1: Weight loss of test sample per cubic meter of grinding wheel removed in the test.
Unlike diamond impregnated metal matrix composites (MMC) in which the diamond grains are frequently plucked out of the MMC, there was no evidence of this wear mechanism in these worn surfaces.
Significantly, none of the worn surfaces showed evidence of diamond grain being plucked from the matrix indicating strong bonding between the diamond and composite matrix.

Based on the theory of poisson ratio testing by wave velocity and a large number of indoor experiments, the poisson ratio characteristic of soil-rock mixture which contains cohesionless soil and stone is analyzed in different conditions.
Indoor experiment Equipments and facilities contain a large vibrating compression equipment which is shown in Fig.1, a GJY-1 engineering testing equipment, longitudinal wave senores (60Hz), shear wave senores (28Hz), XB-150 soil-piezometers, cymometers etc. and the parameters of the large vibrating compression equipment: mass of the vibrating hammer is 138kg, vibration frequency is 0~60Hz, swing is 0.35~0.65mm, vibrating force is 5.4-9.6kN, size of container is 500mm×1000mm, consent maximum grain is 90mm. 1.
Grain composition of the samples is obtained by Talbot Optimization Grading Formulation.
Scilicet, poisson ratio could be described with a binary function which includes two unknown numerical numbers stone content and water content.