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It is a number describing how much that sample resists the flow of electricity; resistivity is measured in units of ohm meters.
Comparisons are made between different two alloys. [8] The reason why resistivity increases with increasing temperature is that the number of imperfection in the atomic lattice structure increases with temperature and this hampers electron movement.
In time, these copper-rich compounds migrate to the metallic grain boundaries and they interfere with movement between slip-planes as load is applied to the material. 2.2 Quenching Process Cold water is the most common quenching medium.
Elastic deformation is a change in shape of a material at low stress that is recoverable after the stress is removed, but Plastic deformation involves the breaking of a limited number of atomic bonds by the movement of dislocations.

Although their main use is to prevent particles from clumping, they offer a number of other benefits: • Complete, or at least partial, elimination of the phenomenon of particles sticking to the grinding bodies
For this reason, the grinding time cannot be determined exactly, and therefore the number of passes (falls) of the ground raw material through the mill is indicated.
The problem with the wear of the rotors which is probably caused by inappropriate grain morphology and insufficient pre-grinding of the sample was solved here.
Sample Number of drops 1 2 3 4 5 6 7 8 9 10 Specific Surface Area [m2/kg] Cement 281 299 281 277 279 267 267 258 255 252 Cement+ SIKA ViscoCrete PC 1 273 301 313 296 301 327 346 343 318 331 Cement + SIKA ViscoCrete SK 3,2 272 295 276 280 277 274 276 266 265 255 The problem with this grinding technology is that it does not ensure perfect dispersion of the intensifier in the sample.

Micro-geometrical profile parameters were measured by a profilometer a2 dp dg Li Work surface 2α △Lc △Lg Fig.2 Schematic diagram of a spherical grain removal material from workpiece surface TALSURF5, and SEM was used to observe surface micro-morphology.
The higher the abrasive concentration was, the greater number of effective abrasive there was participated in machining, and the stronger the sliding-friction effect on workpiece surface became, which better uniformed and reduced surface roughness and waviness.
Fig.3 Effect of abrasive mesh size on △Ra value Fig.4 Effect of percentage abrasive concentration on Ra values at different number of cycles Effect of Initial Abrasive Jet Speed on Surface Roughness.
Cai: Journal of Northeastern University (Natural Science), Vol. 26 (6) Fig.5 Effect of number of cycles on surface roughness percentage improvement △Ra% Fig.6 Effect of media flow speed on △R value (2005), pp.578-581.

The Vickers hardness numbers were taken at the cross section at half of the depth of the weld at spacing distance of 0.1mm between each indentation.
The interfaces of the weld have grain distortion feature, and a pair of the base metals in some weldment are not in the same plane as expressed in Figure 1(a).
Figure 2 shows the Vickers hardness numbers are higher in the weld and neighboring region but lower in the base metal that far from the weld region.
Compare these figures, the distribution of the higher Vickers numbers closed to the interface (see Figure 2) is wider than the widths of the welds (see Figures 1(j) ~ 1(l)).

The absorption peak of MoO3 in the Ni-doping catalyst gradually moved to lower wave number areas compared with that of the pure Fe-Mo catalyst.
Moreover, the absorption peaks locations moved significantly to the low wave number area.
Thus, an increasing number of lattice oxygen (O2-) in the catalyst would improve its activity.
Excessive amounts of Ni will damage the structure of Fe2 (MoO4)3, the addition of Ni not only reduces Mo5+ content but also influences the grain structure of the catalyst and changes the state of Mo species.

However, the precipitates can play a number of roles in the total thermal-mechanical history of the material.
This is consistent with TEM observations which show that the number of Orowan loops around the precipitates increase with deformation strain for these samples.
The number of lath shaped particles decreases and plate shaped particles appear.
a) b) c) d) Fig.5 a) Evolution of yield stress during annealing, b) cell structure in sample aged 7days at 325oC, cold rolled 40% and then annealed at 325oC for 100 min c) dislocation network and d) recrystallized grain in sample aged 7 days at 250oC, cold rolled 40% and then annealed at 325 oC for 7 days (Note: equilibrium phases Q and β formed during annealing). 0 40 80 120 160 200 240 280 10 100 1000 10000 100000 1000000 10000000 Time (s) YS (MPa) SSS-Aged 325C,7days-CR40%-Annealed 325C SSS-Aged 250C,7days-CR40%-Annealed 325C4.

The trial serial numbers and surface roughness of the normal honing and ultrasonic honing are taken as horizontal coordinate, vertical coordinate respectively, and the test results are shown in Fig. 4.
Relative to the general honing, ultrasonic honing can improve the honing surface quality with less grinding force impacted on single grain; during the ultrasonic honing process, vibration at 18.6 KHz is added on the whetstone, which is seldom plugged, and under the high-frequency vibration and flushing lubricant make small chips more difficult to be stored in whetstone hole in debris to avoid "second cutting" machined surface.
Those experiments’ numbers are selected only if the actual test material removal rate greater than zero, then to plot the results with those experiments’ numbers as horizontal coordinates and the actual material removal rate of calculated ordinary and ultrasonic honing as vertical coordinates, which is shown in Fig. 6: Fig.6 Actual material removal rate test chart By analyzing the removal rate of ultrasonic vibration honing Nd-Fe-B permanent magnet material process, it concludes that the actual grinding depth of ultrasonic honing processing, ap-actual is larger than ap, and so the actual material removal rate also increased, which indicating the advantages of ultrasonic vibration honing Nd-Fe-B permanent magnet material, but also it verifies the removal model of ultrasonic vibration honing Nd-Fe-B material.

(a) second section curve (b) fourth section curve (c) 15th section curve (d) 20th section curve (e) 23th section curve (f) 25th section curve Fig. 3 Model by through the point Fig. 4 Model by combination modeling method We know UG provides a variety of curved surface tectonic methods, including straight grain surface, through the curve group, through the curve grid, scanning, etc.
The project number is YK07-01-11.
The international Journal of Advanced Manufacturing Technology, 2005, Volume 27, Numbers 11-12, Pages 1119-1123 [10] Xavier Pessoles, Yann Landon and Walter Rubio, Kinematic modelling of a 3-axis NC machine tool in linear and circular interpolation.
The International Journal of Advanced Manufacturing Technology, 2010, Volume 47, Numbers 5-8, Pages 639-655

Soil surface roughness is very important in soil wind erosion prediction, because it influences trapping and emission of soil particles, abrasion of the soil surface by sultating grains, and the development of wind profiles [1].
The method of rms height statistics is as follows: (1) where: n is the number of observations taken per sample; s(x) is the surface height a point x in the surface profile; and is the average height of the surface profile.
In this article, D is calculated by root mean square(RMS) method. fractal dimensions were calculated from the average deviation around the mean elevation value of all points located inside a box with size h. average values of RMS, denoted as S(h), for different scale ranges h, were calculated according to: (3) where is the total number of boxs of size h, is the number of points in a box of size h, is the measured value of profile curve that correspond to the position, represents the average elevation value for all points in the ith box, C is scale parameter, is fractal dimension.

The Xianghai nature reserve have six of the crane, accounting for 40% of the total number of crane in world, accounting for two-thirds of the total number of crane in China .
The Xianghai wetland not only has rich natural resources, also there is a huge environment regulating function and ecological benefit, it in protecting biodiversity, maintain freshwater resources, resist flood, adjusting the climate, the degradation of pollutants and provide for human life and production resources play an important role, and is also the northeast of the Songliao plain major grain producing areas important ecological barrier.
In recent years, due to the influence of the global climate, the Xianghai wetland in serious drought, the river flow, water level drops, aquatic plants degradation are the decrease in the number of species, cause wetland atrophy, which greatly reduces the Xianghai nature reserve as an international important wetland, important birds breeding, migration and the habitat of the role.