Effects of Sc2O3 and MgO passivation layerson the output power of AlGaN/GaN HEMTs

The low temperature (100°C) deposition of Sc₂O₃ or MgO layers is found to significantly increase the output power of AlGaN/GaN HEMTs. At 4 GHz, there was a better than 3 dB increase in output power of 0.5×100 μm² HEMTs for both types of oxide passivation layers. Both Sc₂ O₃ and MgO produced larger output power increases at 4 GHz than conventional plasma-enhanced chemical vapor deposited (PECVD) SiN_x passivation which typically showed ⩽2 dB increase on the same types of devices. The HEMT gain also in general remained linear over a wider input power range with the Sc₂O₃ or MgO passivation. These films appear promising for reducing the effects of surface states on the DC and RF performance of AlGaN/GaN HEMTs     

Performance enhancement of an induction motor by secondaryimpedance control

The paper demonstrates the use of nonresistive secondary control of an induction motor to improve efficiency, power factor and torque. A mathematical algorithm is presented to predict the control requirements in terms of secondary capacitance. The required secondary capacitance is implemented by a novel electronic switching technique that effectively increases the value of the used capacitor. This overcomes the high-capacitance demand and provides a feasible solution. Experimental verification is presented in the results obtained from a small induction motor drive     

Dewatering of liwuid radioactive wastes in thin-film rotary evaporators

Translated from Atomnaya Énergiya, Vol. 67, No. 1, pp. 11–15, July, 1989.     

Transitional Architectures for Enterprise Evolution

To transform your IT architecture, consider implementing discrete plateaus to provide stability and manage change while you move gradually closer to your goal.     

Applications of an Infrared Imager for Determining Temperature Fields in Gas Flows

A device containing a temperature converter with an infrared camera is described. Its application allows one to instantly measure the temperature field of a gas flow in regions of arbitrary sizes.