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Properties of the Obtained Porous Si3N4-SiO2 composites Sample Numbers Porosity Thermal conductivity [W/m·K] Compression strength [MPa] S-D1(Sol-gel+Freeze-Drying,1200 oC) 64~80 0.08-0.1 15~17 S-D2(Sol-gel+conventional drying, 1200 oC) 58~63 0.11-0.13 16~17 S-D3(Sol-gel+Freeze-Drying,1300 oC) 60~73 0.1-0.12 20~25 Results and discussion Phases analysis.
It was found that two kinds of pores appeared in the specimens , one is the larger open pores with pore size of 1~5 μm in grain boundary and the porosity is about 20%~30%; The other, closed pores, is the nanometer level in the grain with pore size, and the volume is more than 50%.

Marked progress was due by, principally, high level and/or unique combination of a number of structure-related physical properties (principally magnetic and mechanical) of alloys in disordered state [3-5].
The annealing purpose is the obtaining nanocrystalline state to all product volume without transition into temperature range in which recrystallization process leads to structure with larger grains having significantly worse properties, is implemented.
It can be assumed, that the phases separation on grain boundary are process taking priority of one fast growth at recrystallization.

By repeating this process a number of times a solid 3D object of intended shape is fabricated.
At slow and fast cooling rates, the β-phase transforms to the acicular α-phase and metastable hexagonal α’-martensite and some residual β at grain boundaries, respectively.
Owing to the high temperature gradients that happen during the SLM process, the microstructure of the as-built SLM samples comprises of a martensitic α′-phase within prior β grains that are mostly aligned with the building direction.

The granularity of mid-fan become smaller compared with fan root, the lithology is mainly characterized by gritstone and grained sandstone, the amplitude of the electric curves become lower.
Fanlike sand body is accumulated in the deep lake area by a great number of debris which is carried by turbidity current of sublacustrine fan system, its shape commonly like huge lensing in the dark mudstone[10].It mainly developed in retrogradation sequence sets (Sq2,Sq3) of fault depression super sequence, formed a setting of grey black mud shale of a semi-deep lake, represented a set of anti-size grading sandtone sedimentation ,containing the debris of land sources transported by the gravity flow and rapid accumulation.
The lithology of fan delta can make a transition from grained sandstone to mudstone.

Ultrasonic liquid processing depends on a number of parameters, such as amplitude, pressure, temperature, and viscosity.
Katgerman, Influence of ultrasonic melt treatment on the formation of primary intermetallics and related grain refinement in aluminum alloys, J.
Ma, Ultrasonic grain refinement of magnesium and its alloys, InTec, Available from: (2011).

Research in natural fibres, such as sisal, coconut, flax, jute, hemp, bamboo, wood, palm fibres, straw, and their possible application in and outside of civil engineering is being carried out by a number of experts worldwide, e.g.
As an aggregate, lightweight expanded glass with grains sized 0.25‒0.5, 0.5‒1 and 1‒2 was chozen and also expanded perlite, grain size 0.315‒2.5.

Design principles of thermal insulation materials (1)Optimize the design of the grain size and grain gradation of styrofoam particles and the best ratio of that with other gelled material to make the density, thermal conductivity, heat storage coefficient, shrinkage and strength and other performance indicators have been optimized
(3)The introduction of additives make a large number of bubbles, cut off the heat transmission channel, not only reached the thermal insulation effect, but also improve the water keeping effects, the degree of cement hydration and insulation strength

Fig.2 also show that the shrinkage rate for all the samples reaches to peak value at about 1700 °C, a large number of low-viscosity liquid should is formed, which indicates that the formation of SiAlON has little been affected by h-BN.
There should initiate microcrack in SiAlON/BN composite materials during cooling after sintering, and the cohesion between grains is incremented, and the thermal stress also be erased fowling the microcrack closed when test sample heating.
Kim, Growth of elongated grains in α-SiAlON ceramics, Mater.

A number of cutting experiments with single abrasive grit were performed to study the mechanism of grit-workpiece interaction [1].
Simulative model of single grit cutting Geometric Model of Single Grit In authors’ previous research, white light interferometer was employed to measure the surface topography of alumina grinding wheels with different grain size [8].
Rong, Research on microscopic grain-workpiece interaction in grinding through micro-cutting simulation, part 2: factorial study, Adv.

When increasing the charge to 2C, the Sn grains increase and begin to show a tetragonal crystal shape while the pore size reduced a little (Fig. 2b).
The Sn grains also grow over 200 nm with a clear tetragonal structure.
With the increase of cycle number, the charge and discharge plateaus are becoming less obvious, which indicate the capacity loss with cycles.