The Mg 2+ and Ga 3+ cation distributions in the MgGa 2 O 4 lattice were characterized by refinement of crystal structure firing temperature dependence microwave dielectric properties was described this study. ceramics fired at different temperatures indicated that degree inversion x , which represents 8( a ) 16( d sites (Mg 1- )[Mg 2- ]O slightly decreases from 0.88 to 0.84 with increasing 1500 1600 °C. This implies preferentially occupies site, i.e., tetrahedral temperature. constant (ε r...

MgO ceramics with a nominal composition of (1- x )MgO– LiF ( = 0.02–0.10) were synthesized and the effects addition sintering conditions on microwave dielectric properties investigated in this study. With addition, well-sintered at 950 °C covered crucible, Q · f value LiF-added ceramic strongly depended amount time. As result, 0.96MgO–0.04LiF =0.04) exhibited highest 751,500 GHz (ε r 9.6 TCf - 56 ppm/°C) when they sintered for 100 h crucible. The endothermic reaction was observed by...

Abstract Mg 0.7 Al 2.2 O 4 and 0.4 2.4 ceramics with cation vacancies were synthesized using the molten salt method, relationships between microwave dielectric properties crystal structures of these materials investigated. The 27 NMR spectra indicate that preferential occupation tetrahedral sites by 3+ cations was enhanced introduction vacancies. λ values fired at 1600°C, which correspond to fraction in sites, 0.37 0.60, respectively. Crystal structure refinements Rietveld method suggest are...

The dielectric and thermal properties of isotactic polypropylene/magnesium oxide (0–30 vol %) composites were investigated. constant the composite material increased from 2.3 to 3.2 on increasing MgO content observed variation with fraction was in good agreement Bruggeman mixing model. Low losses at microwave frequencies, order 10−4, obtained using highly crystalline as filler, it also found that use larger particle sizes led further reductions loss. absolute value temperature coefficient...

The microwave dielectric properties and crystal structure of spinel-structured (1 − x)MgGa2O4–xZnGa2O4 ceramics were characterized in this study. From the linear variation lattice parameters, formation solid solution was obtained over whole composition range. On basis refined atomic coordinates, variations volume tetrahedron octahedron estimated expansion MO4 (M = Mg, Zn, Ga) recognized. covalency cation–oxygen bond 8a site decreased with increasing x, suggesting preferential Zn substitution...

New measurements of the free energy and entropy mixing associated thermodynamic properties liquid Na-Cd Na-In alloys are reported. It is inferred that there exists some kind short-range order Na, whilst a phase separation tendency in Na-rich region. These contradictory features interpreted terms interchange energies which vary as function Na concentration.

The main impetus for this work is the reduction of experimental associated with yield locus identification sheet metal through homogeneous tests. Inverse strategies have been devised to simultaneously extract a number model parameters from an experiment leading non-uniform stress and strain fields. Amongst them, Finite Element Model Updating (FEMU) technique probably most intuitive approach which conclusive proof concept can be found in literature. A thorough understanding, however, key...

The spinel-structured Mg0.4Al2.4−xGaxO4 ceramics were obtained in the composition range of 0.4–1.2. coexistence spinels with and P4332 was suggested from X-ray powder diffraction crystal structure refinement. cation distribution characterized by 27Al 71Ga solid-state NMR it found that Al3+ cations preferentially occupy octahedral site, while tetrahedral site is occupied Ga3+ cations, resulting increase fraction 0.30 to 0.69. No remarkable variation εr Ga substitution for Al (εr ≒ 8.1)...

MgAl2O4 particles were synthesized through the solid-state reaction method (MAO-S) or molten-salt (MAO-M). The crystallinity, particle size, and crystal structure of spinel-structured MAO-S MAO-M characterized these used as dielectric fillers filled into an isotactic polypropylene matrix, up to 30 vol % filler concentration. Significant differences in degree inversion (λ), which represents cation distribution tetrahedral octahedral sites, obtained for by NMR measurements λ value fired 10 h...

ABSTRACT The high‐frequency dielectric, thermal, and mechanical properties of poly(2,6‐dimethyl‐1,4‐phenylene ether)/high‐impact polystyrene (PPE/HIPS) alloys compounded with MgO filler were investigated as a function content. A comparison isotactic polypropylene/MgO composites was also carried out. Composite samples without voids successfully prepared by melt‐kneading hot‐pressing processes. reduction dielectric loss (tan δ) to less than 10 −3 achieved adding 40 vol % the PPE/HIPS alloys....

A holographic 3D printer is a system that produces direct hologram with full-parallax information using the 3-dimensional data of subject from computer. In this paper, we present proposal for reproduction full-color images printer. order to realize color image, selected 3 laser wavelength colors red (λ=633nm), green (λ=533nm), and blue (λ=442nm), built one-step optical projection liquid crystal display. The image obtained by synthesizing in 2D array multiple exposure these wavelengths made...

MgO ceramics with a nominal composition of (1-x)MgO–xLiF (x = 0.02–0.10) were synthesized and the effects LiF addition sintering conditions on microwave dielectric properties investigated in this study. With addition, well-sintered at 950 °C covered crucible, Q·f value LiF-added ceramic strongly depended amount time. As result, 0.96MgO–0.04LiF (x=0.04) exhibited highest 751,500 GHz (εr 9.6 TCf= - 56 ppm/°C) when they sintered for 100 h crucible. The endothermic reaction was observed by...

This paper describes the fatigue strength and subsurface crack initiation behaviour in gasnitrided low alloy steel, SCM 435. Cantilever type rotating bending tests have been conducted at room temperature laboratory air using smooth specimens with different nitrided depths, effect of depth on was evaluated fracture process fish-eye studied basis detailed fractographic examination. The increased increasing could be by equation σw/σn=D/(D-2dn), where σw is limit materials, σn maximum applied...