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71.
Increased use of composites in aerospace and defense application induces the search for heat resistant material. In present
study silica reinforced epoxy functionally graded material using quartz fabric is prepared with different thickness. The gradation
in silica : epoxy matrix is maintained with one side pure epoxy to opposite side pure silica. Thermal and mechanical behaviour
of the composites were studied. It was found that the temperature gradient of 350°C to 950°C could be maintained for 2 to
5 min if the thickness of insulating silica layer is increased from 0.5 mm to 16 mm. Mechanical properties such as flexural
modulus and strength of FGM composites were also evaluated. Strength and modulus decreased with increase of insulating layer. 相似文献
72.
Pandit Subrata Mukherjee Pulok K. Gantait Arunava Ponnusankar Sivasankaran Bhadra Santanu 《平面色谱法杂志一现代薄层色谱法》2011,24(6):541-544
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
73.
Pulok Pattanayak S. Asokan 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,62(3):277-280
Alternating Differential Scanning Calorimetric (ADSC) studies show that Se
rich As20Se80-xAgx (0 ≤ x ≤ 15) glasses
exhibit two endothermic glass transitions and two exothermic crystallization
peaks; the observed thermal behavior has been understood on the basis that
As20Se80-xAgx glasses are microscopically phase separated,
containing Ag2Se phases embedded in an As-Se backbone. With increasing
silver concentration, the Ag2Se phase percolates in the As-Se matrix,
with a well-defined percolation threshold at x = 8. A signature of this
percolation transition is shown up in the thermal behavior, as sudden jumps
in the composition dependence of non-reversing enthalpy, ΔHnr
obtained at the second glass transition reaction. Scanning Electron
Microscopic (SEM) studies also confirm the microscopic phase separation in
these glasses. The super-ionic conduction observed earlier in these glasses
at higher silver proportions, is likely to be associated with the silver
phase percolation. 相似文献