A reliable and convenient system to generate accurate and stable standard gas mixtures of various atmospheric compounds at parts-per-billion levels has been developed. The system is of simple design; the generator is a coil consisting of an inner tube of microporous polytetrafuluoroethylene (PTFE) membrane tubing and an outer tube of silicone tubing. An aqueous solution of the given compound co...

in magnetic abrasive finishing (maf), abrasive grains as a tool move on surface and can removechip from surface of work piece. in this study al 6061 tube was considered as the work piece andthe effect of finishing parameters such as gap distance between tube and poles, rotational speed oftube, abrasive ration and finishing time on surface roughness was investigated. the mixture offerromagnetic ...

A method of speech enhancement is developed that reconstructs clean speech from a set of acoustic features using a sinusoidal model of speech. This is a significant departure from traditional filtering-based methods of speech enhancement. A major challenge with this approach is to estimate accurately the acoustic features (voicing, fundamental frequency, spectral envelope) from noisy speech. Th...

The inner ear and cochleovestibular ganglion (CVG) derive from a specialized region of head ectoderm termed the otic placode. During embryogenesis, the otic placode invaginates into the head to form the otic vesicle (OV), the primordium of the inner ear and CVG. Non-autonomous cell signaling from the hindbrain to the OV is required for inner ear morphogenesis and neurogenesis. In this study, we...

The body’s control system is seen developing during the 4th week of embryonic life. The neural plate folds into a tube which detaches from the general ectoderm and creates the bodily control system as developed from the cells of the neural crest and tube.22,32,40,42 The neural crest cell derivaties are found throughout the body. Basically they gather information from the outer and inner aspects...

Energy transfer from the translational degrees of freedom to phonon modes is studied for isolated systems of two coaxial carbon nanotubes, which may serve as a nearly frictionless nano-oscillator. It is found that for oscillators with short nanotubes (less than 30 A) a rocking motion, occurring when the inner tube is pulled about 1/3 out of the outer tube, is responsible for significant phonon ...

A bubbly flow in a vertical miniature tube is analyzed theoretically. The liquid and gas phase are co-current flowing upward. The gas phase is injected via a nozzle whose inner diameter is 0.11mm and it is placed on the axis of the tube. A force balance is applied on the bubble at its detachment. The set of governing equations are solved by use of Mathematica software. The bubble diameter and t...

In magnetic abrasive finishing (MAF), abrasive grains as a tool move on surface and can remove chip from surface of work piece. In this study AL 6061 tube was considered as the work piece and the effect of finishing parameters such as gap distance between tube and poles, rotational speed of tube, abrasive ration and finishing time on surface roughness was investigated. The mixture of ferromagne...

In magnetic abrasive finishing (MAF), abrasive grains as a tool move on surface and can remove chip from surface of work piece. In this study AL 6061 tube was considered as the work piece and the effect of finishing parameters such as gap distance between tube and poles, rotational speed of tube, abrasive ration and finishing time on surface roughness was investigated. The mixture of ferromagne...

The deflection of a piezoelectric tube, with the outer (or inner) metal coating sectioned into four quadrants, is analyzed. We show that by applying a voltage V on one of the quadrants, the electromechanical deflection is ( Jzd,, VL2/?rDh), where d,, is the piezoel&tric coefficient, L is the length, D the diameter, and h the wall thickness of the tube. The deflections calculated with it agree w...