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In this paper, accord to effect of CBN abrasives in vitrified wheel, eight kinds CBN abrasives were analyzed for its room performance, microcosmic crystal photographs, high temperature performance and corrosion resistance, by right of single grain pressure-resistant intensity apparatus, SEM and DTA etc advanced apparatus.
However, No.8# abrasive size is only two size number smaller than No.1 # and No.2 # abrasive, its static press strength which has reached 5.06(kg) is still more advantage than others.

Moreover, dispersion strengthening mechanism may not be completely applicable because the nanoparticles mainly locate at the grain boundaries [9, 12].
A great number of interface failures result in a higher tensile strength as compared to the non-reinforced aluminum [3].

In this paper , the grain was abstracted as an ideal cone with the top angle of 106°and the height of 0.12mm, while the work piece dimension was 4×3mm.
The number of elements along the direction of grinding depth was about 3 to 4, using the hourglass control method to control the excessive distortion of grids and selecting the reduced first-order linear and plane quadrilateral element for its high stability, shown as Fig.1 .

When the gap voltage is applied to the tool electrode, r : Displacement ε : Degree of eccentricity ω0 : Natural frequency ω : Number of revolutions l : Shaft length m : Mass of the shaft ms : Mass of the electrode d : Shaft diameter E : Young's modulus z : Damping ratio ms l r d m Fig. 2 Cantilever model.
In finishing process, aluminum oxide film 2 μm in mean grain size was attached to copper pipe of 6 mm in diameter and the pipe was chucked on the turning machine.

Result and discussion 1.3 Calculation of the maximum pH value obtainable on the interface Due to the inhomogeneity of the metal surface, deficiencies, such as grain boundaries, impurities, sediments, intercrystalline compounds, and natural oxide films were discovered, among others.
Fick’s first law posits that under a steady state [7], the following formula applies: (7) where jc cathodic current density F Faraday constant density of O2 in solution ontology N electron transfer number diffusion coefficient of O2 thickness of diffusion layer density of OH- on the interface density of OH- in solution ontology diffusion coefficient of OH- Under the steady state, the numerical value of is not associated with species in terms of certain fluid, namely, =.

Asphalt pavement water damage: that is under the influence of water or freeze-thaw cycles, due to the action of automobile wheel dynamic loads, hydrodynamic pressure or vacuum aspiration repeat cycles have happened when the water enter into pavement interspace, water gradually into asphalt and aggregate interface, so that adhesion of asphalt gradually lose, bitumen membrane shedding from the stone surface (strip), asphalt mixture out grain, loose, and then the pit phenomenon will form.
At present, for the asphalt cement fiber mechanical and overall performance, as well as fiber to improve the mixture of high and low temperature performance have done a large number of studies by domestic and foreign scholars[1-5], more valuable design ideas and construction experience are obtained, but specifically for the fiber to improve the water stability of asphalt mixtures is still lack systematical awareness.

In Chinese rural area, population cardinal number is large, the cost of construction is low, and an unprecedented change is taking place in energy consumption of rural housing.
The biomass materials which can be utilized directly for building insulation are abundant, such as straw and other grain planting by-products, carvings, net shell and other processing by-product, sawdust, bark, leaves, grass and other forestry processing by-products.

C) Environmental benefits: to protect and improve people's living environment and air quality, China has canceled a number of small boilers.
The borehole data shows that: the layers 200m below the surface in the new campus of Taiyuan university is mainly the quaternary layers:a)Lower pleistocene(Q1): yellow, celadon, brown sandy clay, coarse, medium and fine-grained sand interbedded, lacustrine sediments; b)Middle pleistocene(Q2): yellow, red sandy clay, gravel and sand interbedded; c)Upper pleistocene(Q3): isabelline sandy clay, thin sand, ginger rock.layer; 4)Holocene(Q4): modern alluvial layer, mostly sand, sand and gravel deposits.

Incomplete grain boundaries can be clearly seen in this figure, which confirm that the Ni–B alloy coatings are actually a mixture of nanocrystalline and amorphous phase.
The coatings is mainly made of amorphous phase, nanocrystalline cluster is few in number.

Excessive heat during welding of aluminum alloys results in large and equaled grains in the weld bead [6].
The equation for the SNR of HB characteristic is (1) Table 3 Control factors and their levels Table 4 Summary of experimental layout Where is the number of tests in a trial and is the D/W ratio of weld bead.