in the continuous gas lift operation, compressed gas is injected into the lower section of tubing through annulus. the produced liquid flow rate is a function of gas injection rate and injection depth. all the equations to determine depth of injection assumes constant density for gas based on an average temperature of surface and bottomhole that decreases the accuracy of gas lift design. also g...

When holes are doped into an antiferromagnetic insulator they form a slowly fluctuating array of ‘‘topological defects’’ ~metallic stripes! in which the motion of the holes exhibits a self-organized quasi-onedimensional electronic character. The accompanying lateral confinement of the intervening Mott-insulating regions induces a spin gap or pseudogap in the environment of the stripes. We prese...

The physics of sliding nanofriction at high temperature near the substrate melting point, TM, is so far unexplored. We conducted simulations of hard tips sliding on a prototype non-melting surface, NaCl(100), revealing two distinct and opposite phenomena for ploughing and for grazing friction in this regime. We found a frictional drop close to TM for deep ploughing and wear, but on the contrary...

Electron paramagnetic resonance in ac dissipation was observed due to the Cooper pairs breaking up to their quasiparticle state. This phenomenon is the result of a flux motion on a pinning centers in high temperature superconducting materials. The detection of ac dissipation was performed in a low ac field (15 and 22 MHz) as well as in microwave range. Vortex motion hysteresis loop with magneti...

Field-effect devices based on SiC metal-oxide-semiconductor (MOS) structures are attractive for electronic and sensing applications above 250°C. The MOS device operation in chemically corrosive, high-temperature environments places stringent demands on the stability of the insulating dielectric and the constituent interfaces within the structure. The primary mode of oxide breakdown under these ...

The discovery of superconductors with high critical temperatures (~) has led to a considerable effort to fabricate Josephson junctions operating at temperatures approaching, or even exceeding, 77 K for both scientific investigations and potential applications. Superconductor-normal-superconductor ( SNS) devices, with noble or oxide metals as normal interlayers, are perhaps the most widely explo...

We experimentally demonstrated that nanoribbon field-effect transistors can be used for stable high-temperature applications. The on-current level of the nanoribbon FETs decreases at elevated temperatures due to the degradation of the electron mobility. We propose two methods of compensating for the variation of the current level with the temperature in the range of 25-150°C, involving the appl...

superconducting materials are capable of trapping extremely high magnetic fields. this property and meissner effect of superconductors causes a levitation force between bulk superconductors and a permanent magnet (pm). this levitation force has possible industrial applications such as permanent magnet guideways (pmg). because of the high price of permanent magnets, the optimization of pmg desig...

Combustion synthesis is a special thermophysico-chemical process applied for production of intermetallic compounds. In the present work, a reaction–diffusion numerical model was developed to analyze the combustion synthesis of aluminide intermetallics by self-propagating high-temperature synthesis process. In order to verify the reliability of the numerical model, an experimental setup was desi...