Vision is one of the most powerful forms of non-contact sensing for monitoring and control of manufactusang processes. However, processes involving an arc plasma or flame such as welding or thermal spraying pose particularly challenging problems to conventional vision sensing and processing techniques. The arc or plasma is not typically limited to a single spectral region and thus cannot be eas...

We report a facile and scalable approach to synthesize single-walled carbon nanotubes (SWNTs) with selected diameter distribution by applying a magnetic field perpendicular to the electric field in the arc plasma region. It is found that this magnetic field-induced diameter-selectivity strategy enables the control of the SWNTs with different diameter distributions in different regions, and the ...

Aluminum nitride (AlN) film coatings have been obtained by a new technique of hybrid helikon-arc ion-plasma deposition. Possibility to combine the magnetic-filtered arc plasma deposition technique with a treatment in RF plasma of helicon discharge allowed us to deposit AlN coatings on thermolabile substrates, significantly increasing the deposition rate. A study of spectral properties of AlN fi...

A two-temperature thermal non-equilibrium model is developed and applied to the threedimensional and time-dependent simulation of the flow inside a DC arc plasma torch. A detailed comparison of the results of the non-equilibrium model with those of an equilibrium model is presented. The fluid and electromagnetic equations in both models are approximated numerically in a fully-coupled approach b...

Keyhole arc welding (KAW), including the keyhole double-sided arc welding process being developed at the University of Kentucky and keyhole plasma arc welding, can achieve much deeper narrower penetration than all other arc welding processes. If it could be controlled such that the heat input and weld pool are minimized while at the same time the desired full penetration is guaranteed, it could...

Arc discharge is one of the most efficient and environmental friendly method to synthesize Single Wall Carbon Nanotube (SWCNT). However, due to the ultra-fast synthesis procedure, localization of the SWCNT synthesis in an arc discharge plasma volume in situ has been a long standing problem. This relates to the ability of controlling volumetric synthesis of nanostructures in plasmas in general. ...

Neuropeptide Y (NPY) neurons in the hypothalamic arcuate nucleus (ARC) play an important role in feeding regulation. Plasma levels of ghrelin and insulin show reciprocal dynamics before and after meals. We hypothesized that ghrelin and insulin also exert reciprocal effects on ARC NPY neurons. Cytosolic Ca²⁺ concentration ([Ca²⁺](i)) was measured by fura-2 microfluorometry in single neurons isol...

AIM The aim of the present study was to evaluate these two high intensity light curing units regarding microleakage beneath metal and ceramic brackets. MATERIALS AND METHODS A total of 60 freshly extracted human premolar teeth were randomly divided into four groups of 15 samples; group I: Metal bracket + LED cured, group II: Ceramic bracket + LED cured, group III: Metal bracket + plasma arc c...

A cascade arc facility has been constructed at The University of Tennessee Space Institute (UTSI) to study the effect of nonequilibrium transport properties in hydrogen-nitrogen arcjet propellant plasmas. These studies are being used to guide development of the physical models required for further development of arcjet computational codes. The cascade arc has been operated on hydrogen with a cu...