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In addition, the brittleness and high hardness can also cause strength degradation due to the formation of surface and subsurface cracks and other defects [16-18].Flawless machining, free of brittle fracture was possible by having a critical depth of cut and flattened grains slightly protruding from the surface of the grinding wheel [19].
It was observed [20] that the material removal rate increases and the quality of the ground surface decreases with increasing number of cracks in grinding and cutting of advanced ceramics with diamond grinding wheels containing a binding resin bond.
In ceramics, plastic deformation does not occur during material removal, both the strength and brittleness reduce at high temperatures due to the softening of a glassy phase at the grain boundaries; the material is removed mainly due to the combination of brittle fracture and plastic deformation [39].Although LAM is a comparatively low cost process with improved efficiency, the surface quality of machined by LAM parts leaves something to be desired: when the cutting tool enters and exits the work piece during the laser assisted milling of ceramics (Si3N4), it results in work piece edge chipping at both the entry and exit location [40].An increase in work piece temperature at the cutting zone during LAM of Si3N4 can eliminate both the macro-scale entry and interior edge chippings, but the macro-scale exit edge chipping cannot be avoided completely.

In the general format, austenite transforms into other phases following: dXdt=FT, G, C×SX SX=X0.41-X1-X0.4X (1) where X represents ferrite, pearlite, or bainite phase fractions, F is a function of current temperature at an IP, G, the Prior Austenite Grain Size (PAGS), and C, the steel composition.
(a) Finite element input model showing the temperature distribution (˚{TTP}730 C) for the high speed autogenous weld with the centre of the torch being at the middle; (b) finite element calculation of bainite distribution in the middle of the beam for the slow speed traverse; (c) effect of prior Austenite grain size on the phase transformation from austenite into bainite: finite element results for cooling rate of 3 ˚{TTP}730 C/sec 4.
Comparison between results for ASTM PAGS number 0 and 3 in Fig. 1c shows that the change in the PAGS can change the nature of the transformation sigmoidal function.

Introduction Rice husk (RH) is the outermost layer of a paddy grain which can be separated from rice grain by milling process.
The functional groups of the synthesized and treated silica nanoparticles were analyzed by Fourier transform infrared spectroscopy (FTIR, Spectrum 400 FT-IR/FT-NIR Spectrometer/PerkinElmer) at room temperature over the wave number range from 4000 - 550 cm-1.

The high number of people, who lived in the cities composed of cave-houses, made necessary adjustments to make the places healthy: the underground dwellings, therefore, were equipped with ventilation systems, cisterns, warehouses, wells and small openings not visible to the outdoor but that allowed the exchange air.
In the case of windmills the driving force is the wind: this moves the large blades, made of wood, placed at the top of the structure; a system of gears is connected to these, which move the millstones that grind the grain or operate the mechanisms being used to pump the water.
Over the centuries the system has been applied on several occasions and it is certainly easy to associate the shape of the water mill with the millstones for the grain and, therefore, the production of flour.

The degree of their impact depends on the wood density as well as on the orientation of the wood grain [7].
Altogether sixteen sets of specimens were prepared for the experiment, all of them consisting of seven veneer layers while the grain of veneer in alternate plies was at right angles.
Mechanical properties were determined using a set consisting of an equal number of convex and concave specimens and the properties were determined through statical bend using testing device in accordace with the standard [13].

Besides, using grain crops to produce biodiesel will create a situation of “cars competing with human for food”.
With the rapid development of Chinese economy, the demand for energy will become even bigger, it is estimated that China’s demand for primary energy will be 2.83 billion tons of standard coal equivalent in 2020, which will be twice the number in 2000.
[7] Li Weimin, Yao Jian and Yang Hongli: Making Biodiesel from Hogwash Oil, published on Grain and Food Industry, NO.1, Vol.15, 2008

Increasing the annealing temperature increases also the grain size of the ferrite, which is in concordance with the results of N.
XRD patterns of the four heat-treated doped garnets The morphology of crystal grains of the Al doped yttrium-iron garnets, with different amounts of aluminium was studied by SEM and the results are shown in Fig. 5.
When the aluminium content increases not only the pore diameter will be changed, but number of the larger pores will be decreased too.

From the point of view of electromagnetics, such a highly inhomogeneous material becomes difficult to predict due to the fact that currents can flow only through well connected paths, and the effect of the magnetic field depends strongly on the type and the distribution of defects or grain structure.
Down: corresponding magnetic map number proportional to the average of the field over the surface of the sample: [] ∫∫ −=− dxdyHyxB S HB z 0 0 ),( 1 µ µ (1) where S is the area of the surface of the sample.
From the current maps we can distinguish the critical current in the joint, Jc GB, and the current in each grain, Jc G , the ratio Jc GB/ Jc G is the figure of merit of the weld it is of 0.7 for sample A and 0.96 for sample B.

With the well depth increase and downhole condition more and more complex, the buttress premium thread connections with great joint strength and good sealing property had been developed out successfully and were used in a great number of oil fields [3-4].
The grain size is grade 9.5 and the inclusions of material are A0.5, B0.5, D0.5.
Crack is easy come out at the interface between wide ferrite batten in upper bainite and fat carbide that locate between ferrite battens, and it is impossible to prevent crack extending under the role of small grain boundary, so the ductility of material is cut down by this bad structure.

Each thermocouple is numbered from 1 to 7 as shown in Fig.1 (a).
Many pinholes appear for Ni film and the grain size expands for Cu film [8].
Since the electrical conductivity or resistivity depends on the mean free path of electron or relaxation time for electron, pinhole or large crystal grain seems to affect the electrical property.