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Finally, the terms lapping and fine polishing are very known, however its concept is more known in qualitative terms, that is evident for the fact that industries still continue to specify like rustic, smooth, cloudy, shining or with an adimensional number the finished polished surface.
It showed that the abrasive sandpaper grains of mesh 600 are excessively harder than the surface of the polycarbonate.

We can study them, such as analyzing grains' size, appearance and distribution.
The diagnosis of polluted hydraulic oil A large number of practical experience and theoretical studies show that, many kinds of factors cause the hydraulic oil pollution, but the factors is usually around hydraulic oil.

Compared to casting technology, precision forging of semimonocoque is superior for economy of material and energy, less machining process, lower production cost, continuous distribution of metal streamline, grain refinement, significant higher performance and longer service life.
For complicated forge pieces, the number of finite elements is about at least 15 times that of its volume (cm3) in order to get good simulation effect. 2) Equivalent stress-strain distribution during forming process is analyzed and effect of forging shape on the flow law of metal materials is discussed.

The risk of brittleness under the influence of molten metal is well established, but description of the phenomena is still difficult because of inadequate understanding of its mechanisms and large number of parameters which may be responsible for the LME effect.
Main variables which may be responsible for LME effect are [8-11]: crack propagation rate, deformation during cracking, chemical composition of molten metal (beside the change of physicochemical properties like surface energy and mutual solubility, molten metal influences the effects at the end of a crack, decreases the critical intensity of cracking stress and changes its micromechnisms; additionally the alloying elements of metallizing bath can increase and decrease the brittleness), chemical composition and structure of solid metal, wettability, surface energy and grain boundary energy.

These strategies propose to make the old industrial of the Northeast, Northwest, Southwest and other regions which concentrate the energy and raw materials and machinery manufacturing industry and the cities that relying on grain, coal, oil and other resource-rich regions to become the key of the economic.
Especially in the early days of the ‘the 1st 5 years plan’ and ‘ the 2nd 5 years plan’ period, our country lay emphasis on investing many large-scale modern factories and developing of large numbers of industrial bases.

Simulation step number is taken as 1000, which is sufficient to simulate the stability of composite system [11].
On the issue of how to get good dispersity, uniform grain size of metal nanoparticles, the deep researches with specific theory and experimental methods are needed.

The first mix proportion of ordinary cement-stabilized gravel without fiber is as follows: Cement: gravel=6: 94, optimum moisture content is 5.3%; maximum dry density is 2.292g/cm3; aggregate gradation is medium coarse sand and natural gravel (maximum grain size is less than 3cm) =1:4.
When mixed with right volume content of polypropylene fiber in the cement-stabilized base material, the large number of uniformly distributed fiber in the base material can constraint the base material evenly, increase its resistance to freeze-thaw expansion pressure, and at last improve the freeze-thaw performance.

IP6 is contained in grains of wheat, rice, corn, and soybean [5] and has a strong chelating capability to Ca2+ ions, similar to ethylenediaminetetraacetic acid (EDTA) [6].
Figures 3b-d and f-h show that the number of the HAp particle agglomerates decreased with an increase in the IP6 concentration; surface-modification of HAp with IP6 inhibits the agglomeration of HAp particles.

As seen in the figure, while threading screw and edge dislocations, the latter forming small angle grain boundaries, were clearly detected, no basal plane dislocations were observed over the entire area.
We examined another couple of 4H-SiC boules in addition to other areas of the same boule but hardly detected basal plane dislocations in the crystal part underneath the as-grown growth front of PVT-grown 4H-SiC boules, although we found a number of basal plane dislocations in 4H-SiC substrates sliced out from the portions of the boules well below the growth front.

Introduction Recently, a number of phosphate based bioactive glass ceramics have been widely interested as bioimplants for different biomedical applications, particularly in the context of their chemical composition is closely similar to that of natural bone.
The finely grain powder sample (< 45 mm) of about 30 mg was placed in an alumina crucible and heated at a rate of 5 °C/min, 10 °C/min, 15 °C/min and 20 °C/min respectively from ambient temperature to 1000 °C to study the crystallization kinetics for all the glass samples.