ION-SENSITIVE FIELD-EFFECT TRANSISTORS WITH INORGANIC GATE OXIDE FOR PH SENSING

Ion-sensitive fieldeffect transistors (ISFET’s) have been fabricated by using silicon fiims on sapphire substrates (SOS). Using this structure Si02, Zr02, and TazO5 films are examined as hydrogenion- sensitive materials, and TazO5 fiim has been found to have the highest pH sensitivity (56 mV/pH) among them. The measured pH sensitivity of this SOS-ISFET’s is compared with the theoretical sensitivity based on the site-binding model of proton dimciation reaction on the metal oxide f i i and good agreement between them is obtained

PROPOSAL OF SINGLE-FLUX-QUANTUM LOGIC DEVICE

A new type of logic gate that can be designed using a nonhysteretic Josephson weak link is proposed. The basic component of the proposed device is a one-junction interferometer, and a logic state is represented by either a zero or a single-flux-quantum. In contrast to the “Parametric Quantron,” this device is designed to operate without a three-phase clock and the dependence of the junction critical current on magnetic field is not used. The switching behavior of the device was simulated by computer and an analytical expression for the switching delay has been obtained

PROPOSAL OF SINGLE-FLUX-QUANTUM LOGIC DEVICE

A new type of logic gate that can be designed using a nonhysteretic Josephson weak link is proposed. The basic component of the proposed device is a one-junction interferometer, and a logic state is represented by either a zero or a single-flux-quantum. In contrast to the “Parametric Quantron,” this device is designed to operate without a three-phase clock and the dependence of the junction critical current on magnetic field is not used. The switching behavior of the device was simulated by computer and an analytical expression for the switching delay has been obtained

Investigation of biopharmaceutical and physicochemical drug properties suitable for orally disintegrating tablets

The purpose of this study was to evaluate the biopharmaceutical drug properties suitable for orally disintegrating tablets (ODTs). The net charge at pH 7.4, log D6.5, the highest dose strength, solubility in water, dose number, and elimination t1/2 of 57 ODT drugs and 113 drugs of immediate-release (IR) formulations were compared. These drugs were classified according to the Biopharmaceutical Classification System (BCS). A lower dose strength and a longer elimination t1/2 have been observed as characteristic properties of ODTs. The proportion of basic drugs was higher in the ODTs than in the IR. A significant difference was not observed between the ODT and the IR formulation for log D6.5, solubility in water, and dose number. The distributions of the ODT and IR formulations among each BCS class were similar, suggesting that an ODT can be developed regardless of the BCS class of a drug