The improvement in reverse recovery of power NPN bipolar transistor (BJT) through incorporation of ‘‘universal contact’’ in the base is studied in detail. It is shown that use of universal contact allows redistribution of base current in saturation from collector region where recombination lifetime is high to extrinsic base region where effective recombination lifetime is low. The reverse recov...

A disk pressed from commercial SnO2 powder, sandwiched between two nickel screen current collectors, was used as a lithium-ion secondary anode. Its electrochemical lithium insertion–extraction behavior was investigated by galvanostatic charge–discharge and galvanostatic intermittent titration (GITT) using a microcurrent on one current collector. The transelectrode voltage was measured to monito...

environmental degradation and economic growth are two important proofs in sustainable developmentwhich are followed by steel industry. in this case, energy and environmental damages as sustainabilitypatterns of environment have been investigated in three different dust collectors to select the mostenvironmentally suitable dust collector for electric furnace. in this article, the consumption amo...

The end-product of the electrospinning process is typically a randomly aligned fiber mesh or membrane. This is a result of the electric field generated between the drop of polymer solution at the needle and the collector. The developed electric field causes the stretching of the fibers and their random deposition. By judicious selection of the collector architecture, it is thus possible to deve...

1 Vladan V. Vu kovi , The Faculty of Electronic Engineering, Serbia (phone: 381-018-529523; e-mail: [email protected]). Abstract The paper presents basic construction principles of the universal electronic power regulator using the microcontroller Microchip PIC16F84 coupled with optoelectronic component and standard triac BT 139/800. The device runs using the phase control of the network alter...

Introduction Electrospinning process is broadly used to obtain membrane-like webs with submicron to micron fibers (Li and Xia 2004). Electrospun nanofibers, with its large surface area and multiple pores, can be used to construct unique functional nanostructures for composites, filtration membranes, biomaterials, and breathable textile fabrics (Greiner and Wendorff 2007; Li and Xia 2004; Pham e...

Due to its high theoretical capacity, high energy density, and easy availability, the lithium-sulfur (Li-S) system is considered to be the most promising candidate for electric and hybrid electric vehicle applications. Sulfur/carbon cathode in Li-S batteries still suffers, however, from low Coulombic efficiency and poor cycle life when sulfur loading and the ratio of sulfur to carbon are high. ...

Objective(s): Since the electric field is the main driving force in electrospinning systems, the modeling and analysis of electric field distribution are critical to the nanofibers production. The aim of this study was modeling of the electric field and investigating the various parameters on polyacrylonitrile (PAN) nanofibers morphology and diameter. Methods:</st...