The dye-sensitized solar cells (DSC) provides a technically and economically credible alternative concept to present day p–n junction photovoltaic devices. In contrast to the conventional systems where the semiconductor assume both the task of light absorption and charge carrier transport the two functions are separated here. Light is absorbed by a sensitizer, which is anchored to the surface o...

Objectives: The purpose of this study was to evaluate whether intra-canal application of controlled direct electric current (DEC) could accelerate the amount of orthodontic tooth movement (OTM) in young adult mixed breed dogs. Methods: Fourth premolars of both jaws of five young adult mixed breed dogs were divided into two groups of control and experimental groups. Orthodontic force...

The frequency-dependent nonlinear dielectric increment of dipolar fluids in nonpolar fluids is often measured by using a stationary relaxation method in which two electric fields are used: The static direct current (dc) field of high strength causing the dielectric nonlinearity, and the probing alternating current (ac) field of low strength and high frequency. When a nonlinear composite is subj...

Using a modified ionization model based on nonlocal impact ionization, Miller's relationship is examined for typical reach-through collector VLSI bipolar transistors with collector epi-thickness between 0.025 and 1 /im. The empirical parameter n in Miller's relationship is evaluated under nonlocal impact ionization conditions within the useful range of current gain which corresponds to 0.1 > 1 ...

We have studied the influence of misfit dislocations on hole accumulation in the base layer of an n-AlGaAs/p-GaAs/n-InGaAs heterojunction phototransistor ~HPT!. Spatially and temporally resolved cathodoluminescence ~CL! measurements reveal that variations in the hole accumulation is caused primarily by strain-induced defects which impede the transport of holes in the collector. The lifetime of ...

Mussel seed, obtained from the intertidal zone and permanently immersed collector ropes, was cultivated on ropes suspended from three rafts located at three different sites within the Ria de Arousa (Galicia, NW Spain). Sites were characterized by different levels of phytoplankton availability. The source of seed stock had a marked influence upon subsequent mussel growth; seed originating from c...

Transistor bandwidths are approaching terahertz frequencies. Paramount to high speed transistor operation is submicron device scaling. High bandwidths are obtained with heterojunction bipolar transistors by thinning the base and collector layers, increasing emitter current density, decreasing emitter contact resistivity, and reducing the emitter and collector junction widths. In mesa HBTs, mini...

Solar energy can be converted directly into electric and thermal energy through photovoltaic cells and thermal collectors, respectively. However this conversion, in particular the photovoltaic, has a reduced efficiency. A solution proposed to increase this efficiency is with the hybrid solar structure, which consists in the junction of the photovoltaic panel and the thermal collector in a singl...

Absrmct-A physically based, large signal HBT model is presented to account for the time dependence of the base, collector, and emitter charging currents, as well as self heating effects. The model tracks device performance over eight decades of current. As such, the model can be used as the basis of SPICE modeling approximations, and to this end, examples are presented. A thesis for the diverge...