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Abstract: Carlin Trend gold ores are often refractory by conventional cyanid, for a number reasons:1) the gold is locked up within host sulfide minerals such as pyrite or arsenopyrite; 2) the ore contains carbonaceous compounds which are preg-robbing; 3) the gold is locked up in silicate minerals.
Although the fire assay was the classical methods, but the accuracy and practical are more advantage, especially from the quite a large number of samples of trace metal still have the enrichment of uniquely method.
Let the lead into the furnace of 900 ℃ about 20 min to preheating, closed door 1-2 min, Immediately open door after Lead buckle melt, and black membrane surface withdraws, And at the same time, to temperature control in the 850-900 ℃ or so, until all blowing melt lead over, after the glory of the gold and silver and grain in point, the ash moved to nearby door of dish, After cooling from grey dish out $grain, used for laboratory analysis.

For polycrystalline materials, depending on average grain size and doping level, one or another charge carrier transport mechanism becomes dominant [15].
In this case the barrier mechanism can hardly occur at low temperatures due to significant freezing-off of carriers (small number of carriers in the grain bulk) and low values of thermal energy kT needed to overcome the barrier.
So, the main transport mechanism in the range of hopping conductance is the conductance at grain boundaries.
Short hopping distance at single occupied states (by an order of magnitude smaller than the grain diameter) indicates the significant seggregation of impurities at grain boundaries.
Jump radius via the double occupied states is comparable with the grain size.

A number of X-ray studies on machined surfaces of two- or multi-phase materials have shown that shear stresses which are forbidden at the very surface may be present within the penetration depth of the X-rays [1-3].
As opposed to the steel, polycrystalline tungsten is homogeneous and elastically isotropic on grain level.
A region of significant grain refinement is present at less than 3 µm from the sample surface.
Both samples are structurally graded with a morphology consisting of sub-micron size oblate-like grains located within 1 µm from the sample surface then followed by larger size grains with their long axis aligned along the grinding direction.
Due to the pronounced grain orientation contrast from the ion channelling effect in FIB microscopy, the grain refinement towards the surface can be well resolved with this technique.

The resulting coating remained nanocrystalline with grain size ranges of 27-47nm.
In cross section area of plasma sprayed ceramics coating layers, the columnar grains were always observed.
The microhardness as well as the wear resistance of ceramics materials increases with decreasing in grain size.
The smaller the grain size, the higher the external stress required to induce plastic deformation, microcracking, grain boundary cracking, and grain pull out because the grain boundary becomes larger.
The remarkable characteristic of the plasma sprayed TiO2-ZnO nano-compounded coatings is that there are quite a number of aggregates in white on the splat surface.

It can be explained as follows, for grinding the specimen, due to the action of its surface residual compressive stress field, material lattice contraction, the inter-atomic force field make the surface pores and cracks are in a closed state, so the grains are linked closely together, the material is not easy to wear.
The breaking strength in test pieces after grinded decreases with the grinding depth, this is because the grinding depth, the number and size of grinding crack increase. under the same grinding condition, fracture strength in unheated parts after grinding is higher than the heated parts, this is because the former residual compressive stress value is big, more important is the residual stress depth, surface crack is completely in the compressive stress layer and not easy to expand, shallow depth of the specimen for the residual compressive stress acts, due to the radial cracks is in the tensile stress layer, the tensile stress will tear two fracture surface crack, playe an extended crack, surface microcracks part tip is also possible located tensile stress layer, the fracture strength is reduced.
When the workpiece feedspeed Vw is less than 8m/min, the residual compressive stress increases with increasing of the workpiece feed speed, while Vw greater than 8m/min rapid decline. residual compressive stress increases with the improvement of the wheel speed, when the wheel speed Vs is less than 25m/s, the residual compressive stress with the wheel velocity increases, while Vs is greater than 25m/s residual compressive stress no longer increase, maintain the basic stability. (2) using a diamond grinding wheel grind Al2O3 ceramic, the residual compressive stress decreased with decreasing grain size of diamond grinding wheel. when the grain size is the same, the residual stress is different with different wheel types, using particle size 80/100 diamond grinding wheel, white fused alumina grinding wheel, green silicon carbide grinding wheel to grind Al2O3 ceramic specimens, results showed that the residual compressive stress in green silicon carbide grinding wheel and white corundum grinding
The hardness in diamond grinding wheel is much higher than the grinding specimen, the cutting effect is dominant, and the abrasive grain is not easy passivation, so the residual compressive stress is small.(3) under the same experimental conditions, the measurement residual compressive stress of diamond grinding wheel on three different ceramic materials grinding HP-Si3N4, Al2O3, ZrO2, the results derived compressive residual stress in ZrO2 is greatest, HP-Si3N4followed and Al2O3 minimum, therefore, ceramic grinding surface residual stress sensitivity with different materials affect is higher than it in different grinding conditions.
For a given grinding wheel, grinding force is related to grinding depth and unit area normal grinding force, by using grinding wheel with multiple cutting edge and finer grinding grain size to reduce the load of each particle, can reduce the compressive stress of subsurface zone below surface layer, with the volume of material continuous removed, the sub-surface normal grinding force increase, and the residual compressive stress does not change.

And it has many kinds for difference of carbon fiber orientation or number of layer, in order to utilize the excellent in specific intensity [2].
The tool base material use to tungsten (W) with fine particle type carbide of about 0.2 μm average grain diameter.
As shown in Fig. 6 (a), the average grain diameter of tungsten of the usual carbide tool is approximate 1 μm, so the top of cutting edge roundness radius has approximate 2 μm to 3 μm.
However, as shown in Fig. 6 (b), the case of ultra-super fine tungsten grain diameter of the top of cutting edge roundness radius has approximate 0.5 μm lower.
Fig. 4 The cutting edge of hollow type drill Fig. 5 The sectional view of eccentric between the center Edge round r=2~3 [μm] 5,000×2.00μm Rake face Relief face Edge round r=0.5 [μm] 10,000×1.00μm Rake face Relief face (a) The case of general grain diameter size (b) The case of ultra-super fine grain diameter size Fig. 6 Relationship between tungsten grain size and tool edge roundness (SEM photograph) Experimental Method This experiment used hollow type drill which tool has eccentric penetration hole of developed, as the edge outside diameter is 6.3 mm (shank diameter is 7 mm) and the inside diameter is 4 mm.

Thereby it is assumed that inelastic deformations and plastic flow are caused by slip on a limited number of slip systems and mechanical twinning.
Crystal plasticity model (micro level) The constitutive model used to describe the mechanical behavior on the level of magnesium grains goes back to the work of Asaro and Rice [2, 3].
This texture is then mapped qualitatively to polycrystalline aggregates, discretized by a finite element mesh such that each grain is modeled as one finite element.
This generally allows for non-uniform deformation between and within the grains.
In order to save computational time, however, each polycrystal is modeled by 8*8*8 grains, described by a single 8-noded brick element each.

Introduction In recent years the researches on the grain refinement of the steels are attracting more and more attentions around the world.
Form figure.1 (a) it can be seen that without the relaxation the microstructure is long and wide bainite lathes and the bainite lath can across through an original austenite grain.
An original-austenite grain was divided into several regions, in each region the laths were almost aligning in the same direction and such a region is called a packet.
Acoording to the misorientation distribution of boundaries, it can be seen from Fig.d that in this sample there is only boundaries with misorientation over than 15 o , and there is no boundaries with misorientation lower than 15 o . that is to say there is only high angle boundaries of original austenite grain boundaries and there is no lower angle grain boundaries.
These cell walls are composed of interwoven dislocation network, and a large number of precipitates appear in cells and at cell walls, and these precipitates pin the subgrains and make the substructures stable effectively.

No grain growth was observed with increasing the calcination temperature, as can be seen from Fig.2(l).
More homogenous transition from the precursor compounds into manganite perovskite in the latter case is reflected on the more stable crystal structure formed at 600 oC with only subsequent grain growth noticed with the increase in the annealing temperature.
Improved effective superexchange interaction as the reason for increasing magnetization values with the increase in calcination temperature might be related to the high-temperature induced grain growth in case of the samples prepared in microemulsion, whereas the changes in the crystal structure, including the probable partial changes in Mn valence number implied by the compensation of charges, might be taken as the cause of such dependence in case of the bulk-synthesized sample.
However, it is more homogenous as-dried composition in case of the sample prepared in microemulsion comparing to the one prepared in bulk conditions that might naturally be ascribed to the observed difference in grain growth within these two synthesis approaches.
However, narrow size distribution of the grains of microemulsion-synthesized sample is destroyed after annealing at temperatures higher than 600 oC due to the sintering of grains as is obvious by considering particles morphology transition on 600 oC - 800 oC increase in calcination temperature (Fig. 5g - Fig. 5h).

Therefore, in recent years a number of studies have been made on how to produce acceptable hot bands for drawable cold sheet rolling[2-3].The formability of cold sheets is primarily dependent on their strength level, work hardening ability, morphology of the microstructure and plastic anisotropy.
In most cases, these properties are dominated by the grain size and the crystallographic texture resulting from the final treatment in the batch or continuous annealing furnace[4-6].
The strips having a grain size of 20μm were subsequently cold rolled to 1.0 mm by a 75% reduction using a laboratory mill.
Fig.3 ODF intensities along α- and γ-fibre cold rolling and annealing based on CSP Greater the degree of cold rolling, the {111}<211> texture of γ-fibre increases and density of up to 8.0, but {111} <011> texture content is almost unchanged, remain in 6.0 to 7.0 between.Showed a slight cold deformation can improve the favorable texture {111}<211> orientation density also makes the unstable {001} <110> texture density increased significantly, {001} <110> orientation of the deformed grains, deformation stored energy is low, in the difficult process of batch annealing recrystallization, recrystallization priority easily occur {111} <211> and {111} <110> recrystallized grains "eat", which will benefit after the The annealing process increased {111}<211>and {111}<110> texture .
However γ-fiber increases rapidly since the beginning of recrystallization, and there is a slight decrease in the grain coarsening stage.