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In this study, survival of four probiotic strains ( Lactobacillus acidophilus, L. casei, L. rhamnosus and Bifidobacterium bifidum ) immobilized in edible films based on carboxymethyl cellulose (CMC) and physicochemical properties of films were investigated during 42 days of storage at 4 and 25 °C. Results showed a significant decrease in viability of bacterial cells during 42 days of storage at 25 °C. However, viability of L. acidophilus and L. rhamnosus were in the range of recommended levels during the storage at 4 °C (10 7 CFU/g). Probiotic films caused more water vapor permeability (WVP)and opacity, and less tensile strength (TS) and elongation at break (EB) compared to the control film. However, no significant physicochemical changes were observed among probiotic films containing different strains. Therefore, incorporation of some probiotic strains in edible coats and films could be their suitable carrier at refrigerated temperatures. [ABSTRACT FROM AUTHOR]

In this paper, we propose a fully AlGaN high electron mobility (HEMT) in which the gate electrode, the barrier and the channel are all AlGaN. The p-type AlGaN gate facilitates the normally-off operation to be compatible with the state-of-the-art power amplifiers. In addition, the AlGaN channel increases the breakdown voltage ( V BR ) to 598 V due to the higher breakdown field of AlGaN compared to GaN. To assess the efficiency of the proposed structure, its characteristics are compared with the conventional and recently proposed structures. The two-dimensional device simulation results show that the proposed structure has the highest threshold voltage ( V th ) and the V BR with the moderately low ON-resistance ( R ON ). These features lead to the highest figure of merit (2.49 × 10 12 ) among the structures which is 83%, 59%, 47% and 49% more than those of the conventional, with a field plate, AlGaN gate and AlGaN channel structures, respectively. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present an I–V model for LDMOSFETs. It is based on modeling the Lightly-Doped Drain (LDD) region of the device as voltage-controlled resistors where velocity saturation effect is also taken into account. Using the LDD region model along with a model for the channel region of the device, the on-state I–V characteristic of the transistor is accurately calculated. The models for the LDD region resistors can be incorporated into a circuit simulator such as HSPICE which has an accurate model for the channel region of the transistor. The accuracy of the models is verified by comparing its results with those of a device simulator. The results show a maximum error of 1% for a wide range of voltages and overlapped LDD region lengths. [Copyright &y& Elsevier]