GEOMETRICAL SCALING EFFECTS IN HIGH PERMITTIVITY CAPACITORS

ABSTRACT

In integrated circuit designs, smaller is better; high permittivity films allow circuit designers to save substrate space, but the small geometries of such devices introduce parasitic effects. In this work we investigate the relationship between device geometry and capacitance density, quality factor, and leakage current density. The devices in this study have electrode areas ranging from 12 × 12 μm² to 45 × 45 μm². For each electrode area we have structures with 5 μm, 7.5 μm, 10 μm, 12.5 μm and 15 μm mesa ledges.     

PROTEASE BIOSYNTHESIS FROM LACTOBACILLUS SPECIES: FERMENTATION PARAMETERS AND KINETICS

In the present study, 15 strains of Lactobacillus species, isolated from 25 samples of curd, were screened for their ability to produce extracellular protease. The proteolytic activities of these strains based on casein hydrolysis showed a variation of 1.26–5.80 U/mL with Lactobacillus IH₈ showing a maximum of all. Different cultural conditions for enhanced production of protease by Lactobacillus IH₈ were optimized. It was found that optimal conditions for the production of enzyme were an incubation temperature of 35C and a medium pH of 5.5. The maximum proteolytic activity of Lactobacillus IH₈ (7.28 U/mL) was achieved after 48 h of cultivation. The kinetic parameters such as product yield coefficient (Y p/x), growth yield coefficient (Y x/s), specific product yield coefficient (qp) and specific growth yield coefficient (qx) also revealed that the values of experimental results were highly significant when analyzed kinetically.     

The influence of time elapsed after milking and lactation stage on the lactoperoxidase system of milk in Sahiwal cattle and Nili‐Ravi buffaloes

The effects of time elapsed after milking and lactation stage were assessed on the lactoperoxidase (LP) enzyme activity and concentrations of thiocyanate in Sahiwal cattle (N = 15) and Nili‐Ravi buffaloes (N = 15). The LP activity and thiocyanate concentrations decreased as the time elapsed after milking (P < 0.05) but the concentration of these components increased as the lactation advanced. The LP enzyme activity was sufficient until 12 h post milking but the thiocyanate concentration after 8 h decreased to an insufficient level to activate the LP System, hence additional thiocyanate would be beneficial from external sources. No difference was noted regarding the LPS activity in cattle and buffaloes at the time of collection and subsequently after storage. However, at the end of lactation, the thiocyanate concentration was lower in buffaloes than that in cattle. (P < 0.05).