Objective(s):The aim of this study was to improve flowability and compressibility characteristics of starch to use as a suitable excipient in direct compression tabletting. Quasi-emulsion solvent diffusion was used as a crystal modification method. Materials and Methods: Corn starch was dissolved in hydrochloric acid at 80˚C and then ethanol as a non-solvent was added with lowering temperature ...

In the present study, the conjugate turbulent free convection with the thermal surface radiation in a rectangular enclosure bounded by walls with different thermophysical characteristics in the presence of a local heater is numerically studied. The effects of surface emissivity and wall materials on the air flow and the heat transfer characteristics are the main focus of the present investigati...

This paper describes a theoretical study to investigate the heat transfer characteristics of porous radiant burners. A one dimensional model is used to solve the governing equations for porous medium and gas flow before the premixed flame to the exhaust gas. Combustion in the porous medium is modeled as a spatially dependent heat generation zone. The homogeneous porous media, in addition to its...

In this paper, the cooling performance of water-cooled heat sinks for heat dissipation from electronic components is investigated numerically. Computational Fluid Dynamics (CFD) simulations are carried out to study the rectangular and circular cross-sectional shaped heat sinks. The sectional geometry of channels affects the flow and heat transfer characteristics of minichannel heat sinks. T...

The authors investigate the effect of the thermal boundary resistance between the GaN layer and the substrate on the current–voltage characteristics of GaN MESFETs. Using material specific models for carrier drift-diffusion and thermal conductivity the authors determine the dependence of the breakdown voltage on thermal boundary resistance. The mechanism of the thermal breakdown in GaN transist...

Heterodyne strategies can be used to characterize thermal coupling in integrated circuits when the electrical bandwidth of the dissipating circuit is beyond the bandwidth of the thermal coupling mechanism. From the characterization of the thermal coupling, two possible applications are described: extraction of characteristics of the dissipating circuit (the determination of the center frequency...

To elucidate the three-way relationship among a crystal’s structure, its phonon dispersion characteristics, and its thermal conductivity, an analysis is conducted on layered diatomic Lennard-Jones crystals with various mass ratios. Lattice dynamics theory and molecular dynamics simulations are used to predict the phonon dispersion curves and the thermal conductivity. The layered structure gener...

Evolution of adiabatic remnants of an aspherical supernova explosion in uniform medium are considered. Thermal X-ray emission of such remnants are investigated. It is shown that integral thermal X-ray characteristics (X-ray luminosity and spectrum) of the objects do not allow us to reveal the assymetry in the explosion because these characteristics are close to their Sedov counterparts. Surface...

We studied the evolution of two small flares (GOES class C2 and C1) that developed in the same active region with different morphological characteristics: one is extended and the other is compact. We analyzed the accuracy and the consistency of different algorithms implemented in RHESSI software to reconstruct the image of the emitting sources, for energies between 3 and 12 keV. We found that a...

Three-dimensional (3D) integration has the potential to improve the communication latency and integration density of chip-level multiprocessors (CMPs). However, the stacked high power density layers of 3D CMPs increase the importance and difficulty of thermal management. In this paper, we investigate the 3D CMP run-time thermal management problem and describe efficient management techniques. Th...