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Ahmad, Iftikhar

Publications and source records attributed to Ahmad, Iftikhar.

Apparatus and method for processing battery electrodes

An apparatus for processing battery electrodes includes: a microwave applicator cavity with slots on opposite ends to allow a continuous sheet to move through the cavity in a first direction; a processing chamber constructed of microwave-transparent material, disposed within the applicator cavity and surrounding the continuous sheet, the processing chamber having slots to allow the continuous sheet to pass through it; a microwave power supply to deliver power to the applicator cavity; a source of heated gas providing a controlled gas flow through the processing chamber in a direction opposite the first direction; and, at least one non-contacting temperature measuring device positioned to measure a surface temperature at a selected location on the continuous sheet as it passes through the processing chamber. The apparatus is particularly suited for removing polar solvents from porous electrode coatings. A related method is also disclosed.

Ahmad, Iftikhar↗

Structural, Thermal and Luminescence Properties of AlN:Tm Thin Films Deposited on Silicon Substrate and Optical Fiber

Thin films of AlN:Tm are deposited on a Si(111) and Si(100) substrates and optical fiber by rf magnetron sputtering method. 200–400 nm thick films are deposited at various temperatures to observe the effect of temperature on their structure and morphology. Liquid nitrogen is used to deposit films at low temperature of –196°C. An electric heater is used to grow films at 250–700°C range. The deposited films are analyzed for their structure and thermal stability using X-ray diffraction and thermogravimetric analysis. Films deposited at liquid nitrogen temperature are amorphous and those deposited at high temperature are crystalline. Average grain size, strain and interatomic distance of the crystalline films are calculated. The grain size and inter-atomic distance increase from 36.54 to 45.12 nm and from 0.2368 to 0.25 nm respectively. Photoluminescence of the films excited by 783 nm crystal laser shows an intense infrared emission from Tm{sup +3} at 802 nm as a result of {sup 3}H{sub 4} → {sup 3}H{sub 6} transition.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗