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Shrinkage ratio was denoted by the ratio of length variation value to original length, positive number indicating shrinkage and negative indicating swell. 2.2.2 Volume measurement After mixed, the fresh concrete was poured into a glass bottle with a 5 L or 2.5 L capacity, and the concrete mass was about the 4/5 of the bottle capacity, then, Liquid paraffin was poured at the top of the concrete, cork the bottle, there was a glass tube in the middle of the cork, and then sealed the cork with Vaseline immediately, as shown in Fig.1. the glass tube had a scale, with the decrease of the concrete volume, the liquid level in tube will drop, the dropped value was used to express the volume change of concrete.
The maximum diameter and grain diameter distribution of aggregate have no direct influence on shrinkage.
However, the aggregates with larger diameter and good grain diameter distribution can reduce the mixing water, which reduce the cement paste content, and leads to a smaller shrinkage for concrete.

Though FSP has been basically advanced as a grain refinement technique, it is a very attractive process for also fabricating composites.
Also results revels that with the increase in sinteringtemperature, the number of pores decreased and therate of grain growth apparently increased.However, this method requires alloy powders that are generally more expensive than bulk material, and involves complicated processes during the material fabrication.

In 1986, Babcock & Wilcox Company designed and built the portable, ultrasonic Nondestructive Oxide Thickness Inspection System (NOTIS®) for measuring oxide scale in the inner surface of tubes[3], which makes it possible to nondestructively assess a large number of tubes in a relatively short time.
Schematic representation of the tube configuration with oxide scale grown on steam side The alloy was assumed to be T22 (2¼Cr-1Mo), a ferritic alloy commonly used for boiler superheater and reheater tubes, which forms oxide scales in steam that typically consist of two main layers: an inner layer next to the alloy (usually fine-grained) consisting of Fe-Cr spinel [(Fe,Cr)3O4], and an outer layer which has a columnar-grained structure, and consists of essentially magnetite(Fe3O4).

The gray blocks are SiC grains from the Si-C reaction.
The small gray blocks are β-SiC grains from the Si-C reaction.
The thickness and density of the struts of the products are decided by the silica content in the C/SiO2 composite that depends on the number of cycles of the impregnation procedure.

Property Clean soil Natural water content, wn(%) 28.3 Plastic limit, wP (%) 22.6 Liquid limit, wL (%) 43.5 Specific gravity, Gs 2.75 Soil pH 7.93 Grain size distribution (%) Clay particle fraction 17.3 Silt particle fraction 80.4 Sand particle fraction 2.3 Number of replicates : 3, Confidence interval (CI) : ≥95%, and standard deviation (SD) : <5% Powdered phosphate rock used in this study is provided by Yiwu Xudong Phosphate Rock Co., Ltd.
It can be seen from Fig. 4 that products taking part in the reaction include Mg(OH)2 (i.e. the hydration product of MgO), MgKPO4·6H2O and Mg3(PO4)·8H2O (gels), Zn3(PO4)2·2H2O and CaZn2(PO4)2·2H2O (grain particles partly found on the surface of phosphate rock), and large amount of dispersed particles Pb5(PO4)3.

Since the differentiation of the material is associated with the aggregation and disaggregation of particles - grains of hydrating materials, the rate of heat release and, as a consequence, the temperature in a thermally open system will change.
From Fig. 7 it is clear that the appearance of a large number of cells of large area indicates the presence of large areas with a constant temperature.
As a result, the basis for predicting strength characteristics can be the Voronoi network [19], built on polyhedra, each of which contains areas filled with material closest to the analyzed structure-forming fraction (grain of the original binder, filler particle, pores [15]) than to neighboring objects.

Notwithstanding this is an excellent performance, such systems still have two main limitations: a) the low thermomechanical resistance due to the high porosity (mainly in those materials with pore volume fraction above 50%) and b) the reduction of porosity caused by sintering and grain growth phenomena which intensify above 1100 °C [7].
The S/N ratio for thermal conductivity specified by Taguchi as given below: SN=-10log1n{y12+y22+------+yn2} (1) Wherein, the thermal conductivity response is represented by y1, y2,…. yn, and n is representing the number of observations.
Thermal Resistance of Grain Boundaries in Alumina Ceramics and Refractories.

There were coupling relation between metallic cations Ni2+(Mo4+) and OH- negative ion in preparation conditions, because the lower h.e. overpotential of Mo, the hydrogen evolution in electrolysis progress was obviously effecting the growth ability of forming grain, and forcing the crystal lattice breakdown, which forms a number of nuclei of atoms.
The nanocrystal size was extremely small, which lead to the grain boundary increase.

The superplastic deformations are possible in a narrow gap of temperature (870°C to 950°C for TA6V for fine grain and can be reduced to 750°C for Ultra Fine Grain alloys).
If any solution cannot be found, the cover design will be revised: the change of the number and the position of the lamps, the maximal power delivered and the type of reflectors.

To date, a large number of studies have been carried out to address corrosion issues and to improve the corrosion performance of Mg alloys [1,2].
All samples were mechanically ground for surface standardization with silicon carbide (SiC) papers with the decreasing of the grain size of the abrasive material down to 15 μm and further polished with aluminum oxide paper with the grain size down to 3 μm.