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The term glass is considered by most scientists to be all amorphous or non-crystalline solid due to deficiency of grain boundaries exist in the glass that display glass transition or transformation performance regardless of their preparation technique.
Table 1 The glass composition of (55-x) H3BO3-45ZnO-xY2O3 based on their mol% Sample Number Composition (mol%) H3BO3 ZnO Y2O3 S1 55.0 45 0.0 S2 54.5 45 0.5 S3 54.0 45 1.0 S4 53.5 45 1.5 S5 53.0 45 2.0 S6 52.5 45 2.5 Sample Characterization The density of the glass samples was measured at room temperature using toluene as an immersion liquid by Archimedes’ principle and using the following equation: (1) where is the density of the sample, is the density of toluene at room temperature (867kg.m-3), a is the weight of the sample in the air and b is the weight of the sample in the toluene.
In addition, the oxygen packing density was determined by using the equation: (3) where C is the number of oxygen per formula unit, M is the molecular weight and is the density of the sample.
The declination in number of oxygen atoms per unit composition in glass samples may be due to the declination in rigidity, fewer cross linked network [14] which resulted in the increasing number of non-bridging oxygen due to the structure of glass has been further expanded and has becomes loosely packed [16].
Table 2 Physical parameter of the glass sample Sample number Glass composition (mol%) Density (g.cm-3) Molar volume (cm3.mol-1) Oxygen Packing Density (g.atom.L-1) H3BO3 ZnO Y2O3 1 55 45 0 3.433 20.572 102.074 2 54.5 45 0.5 3.429 20.838 100.79 3 54.0 45 1.0 3.449 20.954 100.22 4 53.5 45 1.5 3.459 21.129 99.39 5 53.0 45 2.0 3.470 21.297 98.60 6 52.5 45 2.5 3.478 21.484 97.74 Figure 1 Density and molar volume of the glasses containing different compositions of Y2O3 Figure 2 Oxygen Packing Density of the glasses containing different compositions of Y2O3 Mechanical properties From the Table 3 and Figure 3, the micro hardness values of the glass show a linear behavior as the values decreased from 518.80 N.mm-2 to 453.13 N.mm-2 with the increasing of the Y2O3 content from 0.0mol% to 2.5mol%.

The spectra were evaluated based on database entries matching pure ZnO with entry number 9008877 and pure Mn2O3 with entry number 1514113.
Refinement Result Lattice parameters of film AC-Mn2O3ZnONR Parameter Data Base Refinement MZnONR1 MZnONR2 MZnONR3 a = b= c (Å) 9,432 9,333 9,112 8,922 V (Å3) 838,56 811,325 756,55 709,821 X2 - 1,39 1,906 1,604 Rp - 0,1832 0,2212 0,1919 Rwp - 0,2426 0,3007 0,2658 Crystallinity (%) 56 49 43 Based on the database matching pure ZnO with entry number 9008877 and pure Mn2O3 with entry number 1514113, the diffraction phase analysis results of the Mn2O3/ZnONR-AC-CB/aluminum composite found that the pure phase of Mn2O3 and ZnO has success synthesized [22].
The bonding of manganese oxide minerals is represented by the wave number 650 cm-1 [25,26], and wavenumber 860 cm-1 indicates the manganese carbonate phase has been completely transformed to manganese oxide [27].
The reduced grain size distribution increases the material's porosity, reactivity, and mechanical characteristics, making it more active due to its wide surface area and high surface mobility[34–36] Fig 7.

The annual output of Chinese synthetic diamond up to now is approaching 4.4 billion carats and this annual output has undoubtedly become the number one since year 2000.
The height of protrusion can reach 70%-80% of the grain diameter.
In recent years, a number of international high-level products have been developed and have met the demands of manufacturing industry.
However, the number of domestic clients who own 160 m/s machines are limited, therefore they can not be widely used in China.
While in 2002 this number was 68, which shows an increase of 36.

Such constraints may be grain boundaries [25], incompatible twin variants [26], crystal defects and impurities [22], and mechanical damage of the surface [27].
The evolution of the cracks with the number of cycles is presented in Fig. 6b.
(b) Evolution of the crack pattern with the number of actuation cycles.
The twinning stress, when observed from the stress-strain-loops (Fig. 7a), showed an increase as the number of cycles accumulated to level of several hundred millions.
Strain output as a function of number of cycles of a Ni-Mn-Ga stick with dimensions 3x5x20 mm3 cycled at 20 Hz in a MSM actuator. © ETO MAGNETIC GmbH, published with permission.

Weber (We) and Reynold (Re) numbers represent a flow pattern during the drop formation process in a DoD system [17].
Rheological constraints in a DoD system for a Newtonian fluid is determined by dimensionless Ohnesorge number [13,14,18]: 1Oh= ReWe= γρa12η (3) where ρ, γ, and η are the density, surface tension, and dynamic viscosity of the binder liquid, respectively, a being the nozzle head diameter.
By plotting Weber against Reynold number, a parametric space is generated that can be used to identify a printable region.
Ohnesorge number is a Newtonian fluid property, and therefore for a non-Newtonian fluid it can be calculated in the shear rate range of interest.
Although the droplets' energy increases as the print speed increases while keeping the other parameters constant, the amount of binder per unit length decreases, meaning smaller numbers of particles are connected.

(1) Where D was the average thickness of the grain perpendicular to the crystal plane direction. where λ was the wavelength of the X-ray source, and β was the full width at half maximum of the peak concerned, and θ was the diffraction angle.
That was because the fixed catalyst amount bears a limited number of active sites [26], which can only carry a proportional number of COD and NH4+-N, over a certain concentration, that was 600 mg/L, the number of active sites were insufficient for excessive COD and NH4+-N oxidation.
Fig. 7 Effects on the properties in the volume of hydrogen peroxide solution to the photocatalytic oxidation 3.3 Orthogonal Design In order to study the method of multi-factor multistage design, we use orthogonal experimental design to find the optimal horizontal combination through a small number of experiments.
The doping of Sn4+ improves the photocatalytic performance of TiO2, mainly by suppressing the recombination of photogenerated electrons and holes, increasing the number of electrons and holes participating in the degradation process.

Waitz [28] studied the fine twin structure of martensite depending on the grain size D, which varied widely from 15 µm to 50 nm in monophase TiNi alloys.
Simultaneously, in these crystals the new tasks concerning the influence of the number of crystallographic variants of non-equiaxial particles on MT can be assigned.
Analysis of the SE curves in Fig. 35 shows that the stress at which stress-induced MT starts, σcr and the value of Δσ depend on the number of variant particles.
Secondly, the staging of σ(ε) curves, the value of stress hysteresis Δσ, and the value of SE depend on the number of particle variants.
Werner, Solid solution and grain size hardening of nitrogen – alloyed austenitic steels, Mater.

There are a number of types of materials that have been (and will be) used for thermal protection of space vehicles.
The number and layout of sensors will be influenced by the specific acoustic properties of different TPS materials.
This topology provides a level of protection against the loss of very large numbers of sensors in the event of fibre breakage.
High purity single crystal alumina (sapphire) is effectively transparent in the near IR region, so the main absorption mechanisms are likely to result from scattering by grain boundaries within the fibres, by the porous microstructure and possibly by impurities.
Figure 7: The measured attenuation through increasing numbers of switch/connector pairs in the network.

A number of semi-empirical equations [40] are proposed to account for the temperature dependent dielectric behaviour.
The defects depend on either intrinsic or extrinsic heterogeneities due to special heat treatments, ionic substitutions, grain size, additives, and grain boundary nature [48].
Thus, apart from the external electric field and the fields locally generated by polarization mismatch at grain boundaries, relaxors contain sources of local electric fields within the individual grains.
We have recently synthesized a number of niobates in the pure phase with high density by optimizing the process parameters [192].
The above equation describes the high temperature (T > Tm) dielectric permittivity quite well in a number of relaxor ferroelectrics.

The superposition principle, the first assumption of the linear elastic fracture mechanics approach, involves addition of the respective stress intensity factor (SIF) for the applied stresses, so that the total stress intensity factor Ktot = Kapply + Kres and the values of K at the peak and valley of the stress cycles are: max max min min tot apply res tot apply res K K K K K K − − − − = + = + (1) The stress intensity factor, Kres, due to the residual stress field is usually obtained using a linear elastic weight function which is actually a versatile method of determining stress intensity factors for many situations and is especially suited where, for a given geometry, a large number of stress intensity factor solutions for complex loading are desired.
:SW 12 Experiment Crack length from hole edge, c / mm Number of cycles, N / cycle Rlo = 0 − 0.3 AFGROW Figure 1 (a) Definitions of effective SIF range, ∆Keff ff according to mean stress or crack closure approach.
There are a number of possible reasons for this discrepancy between observed and predicted crack growth from cold expanded holes.
In summary, there is clear evidence from a number of studies that significant relaxation of the residual hoop stress occurs as a result of fatigue crack growth at cold expanded holes and this must be taken account of if accurate damage tolerant predictions are to be made.
Unlike mechanical fastening, welding leads to: • Single load path construction • Changed grain structure and strength near the fusion and Heat Affected Zones (HAZ) • Formation of new sources of initiating defect not present in the wrought alloy • Creation of local and global residual stress fields.