A high-precision, low-voltage, low-power Σ∆ modulator has been designed using a delayed input feedforward architecture and a tracking multi-bit quantizer employing a single comparator. A 0.18-μm CMOS experimental prototype achieves 100 dB of dynamic range, 100-dB peak SNR and 95dB peak SNDR for a signal bandwidth of 25 kHz, while consuming only 870 μW of total power from a 0.7-V supply at a 5-M...

© 2012 ETRI Journal, Volume 34, Number 1, February 2012 Power metal-oxide semiconductor field-effect transistor (MOSFET) devices are widely used in power electronics applications, such as brushless direct current motors and power modules. For a conventional power MOSFET device such as trench double-diffused MOSFET (TDMOS), there is a tradeoff relationship between specific on-state resistance an...

Ethanol production from lignocellulosic biomass comprises pretreatment, hydrolysis, and fermentation. However, several inhibitors are generated during rice straw chemical including furfural, 5-hydroxymethylfurfural (HMF), phenolics. These inhibitors, i.e., furfural HMF, toxic to yeast cells, can negatively impact growth metabolism, reduce the process efficiency yield. Total phenolics also repor...

Simultaneous saccharification and fermentation (SSF) of alkaline hydrogen peroxide pretreated Antigonum leptopus (Linn) leaves to ethanol was optimized using cellulase from Trichoderma reesei QM-9414 (Celluclast from Novo) and Saccharomyces cerevisiae NRRL-Y-132 cells. Response surface methodology (RSM) and a three-level four-variable design were employed to evaluate the effects of SSF process ...

We fabricated high standoff voltage ~450 V! Schottky rectifiers on hydride vapor phase epitaxy grown GaN on sapphire substrate. Several Schottky device geometries were investigated, including lateral geometry with rectangular and circular contacts, mesa devices, and Schottky metal field plate overlapping a SiO2 layer. The best devices were characterized by an ON-state voltage of 4.2 V at a curr...

In many forage legumes, hard seed coat is the main problem impeding thegermination by preventing water and gases transport in seed. We evaluated theeffects of mechanical scarification, chilling, different seedbeds (peat and sand) andtheir combination on the germination ratio and time of 9 naturally grown legumespecies belonging Lathyrus and Vicia genus. Control seeds showed very lowgermination ...

Neste trabalho são propostos métodos analíticos rápidos para a determinação direta de Al, Cu e Fe em água de coco não processada por espectrometria de absorção atômica com atomização eletrotérmica. Para a determinação de Fe, 100 μL das amostras foram diluídos com 1400 μL de solução 0,1% v/v HNO 3 . Alíquotas de 10 μL desta solução foram injetadas no tubo de grafite sem a adição de modificador q...

We report simple and compact V-cavity semiconductor laser capable of full-band wavelength tuning. A half-wave coupler is used to obtain high side-mode suppression ratio (SMSR) without any grating or epitaxial regrowth. Temperature induced gain spectrum shift is employed in combination with the Vernier tuning mechanism to extend the wavelength tuning range beyond the free spectral range limit. W...

Somatosensory information can be modulated by nicotinic acetylcholine receptors (nAChRs) in the superficial dorsal horn of the spinal cord. Nonetheless, the functional significance of nAChRs in the deep dorsal horn of adult animals remains unclear. Using whole-cell patch-clamp recordings from lamina V neurons in the adult rat spinal cord, we investigated whether the activation of nAChRs could m...

The vasoconstrictor angiotensin II (ANG II) inhibits several types of K(+) channels. We examined the inhibitory mechanism of ANG II on voltage-gated K(+) (K(V)) currents (I(K(V))) recorded from isolated rat arterial smooth muscle using patch-clamp techniques. Application of 100 nM ANG II accelerated the activation of I(K(V)) but also caused inactivation. These effects were abolished by the AT(1...