in this research, the effects of temperature, time and grinding on the types of phases in the calcined kaolin and calcite mixture was investigated. differential thermal analysis (dta) and x-ray diffraction of samples showed that gehlenite is formed at 990 ˚c as the main phase which transforms into anorthite with an increase in the temperature to 1200 ˚c. after grinding the mixture and with incr...

In this paper, a new X band Metamaterial (MTM) based ferrite phase shifter is presented. The phase shifter is excited by circular polarized wave base on combination of TE10 and TE01 modes in a square waveguide. In order to synthesize negative refractive index metamaterial (NIM), negative permeability of ferrite slabs in extraordinary mode is mixed with the negative permitivity of printed period...

The rapid increase of non-linear loads in the last three decades has caused electrical quantities such as voltages and currents in 3-phase distribution systems to become distorted waveforms. This paper reviews, explains and discusses some new concepts, definitions and new available theory in the unbalanced and distorted systems. The usefulness of the proposed practical definitions is investigat...

This study was performed to radiographically examine the prevalence of aspiration sites and to evaluate their anatomical correlation with the bronchial patterns. Ten healthy beagle dogs were repeatedly radiographed, at weekly intervals, in the left and right lateral, ventrodorsal (VD) and dorsoventral (DV) positions. Three milliliters of iohexol distilled with same volume of saline was infused ...

The rapid increase of non-linear loads in the last three decades has caused electrical quantities such as voltages and currents in 3-phase distribution systems to become distorted waveforms. This paper reviews, explains and discusses some new concepts, definitions and new available theory in the unbalanced and distorted systems. The usefulness of the proposed practical definitions is investigat...

An 88-year-old woman with advanced Parkinson's disease (stage V on the Yahr scale) had difficulty in expectoration and underwent tracheostomy in 1999. In July 2004, granulation tissue was formed in the tracheal lumen at the tip of the tracheostomy tube, and a standard type silicone T-tube was inserted. Thereafter, she was cared for at home, where she was doing well until early March 2009, when ...

A 23-year-old woman, who had suffered recurrent acute bronchitis, dyspnoea, and stridor, was found to have a tracheal stenosis and complete left main bronchus obstruction. Biopsy of the tumour showed an adenoid cystic carcinoma. After pneumonectomy the trachea was closed through tumour tissue. Two weeks later a right thoracotomy showed that a tumour had invaded the trachea from the carina up to...