Abstract: In a structure of a radio frequency (RF) variable capacitor having a variable range of capacitance between a first minimum value and a first maximum value, and a method of manufacturing the structure, the structure includes a first capacitor, which has a variable range of capacitance between a second minimum value greater than the first minimum value and a second maximum value greater than the first maximum value, and a second capacitor, which is connected in series to the first capacitor and has a capacitance of a fixed value. By the structure and method, a quality factor of a radio frequency (RF) variable capacitor may be increased without adding complex processing steps.

Abstract: Compounds are provided which have the structure wherein Q is C or N, A is O or S, Z is O or a bond, X is CH or N and R1, R2, R2a, R2b, R2c, R3, Y, x, m, and n are as defined herein, which compounds are useful as antidiabetic, hypolipidemic, and antiobesity agents.

Abstract: Compounds are provided which have the structure wherein Q is C or N, A is O or S, Z is O or a bond, X is CH or N and R1, R2, R2a, R2b, R2c, R3, Y, x, m, and n are as defined herein, which compounds are useful as antidiabetic, hypolipidemic, and antiobesity agents.

Abstract: A differential type VCO (Voltage Controllable Oscillator) is disclosed. The VCO has a differential amplifier having a couple of transistors and a couple of LC tanks. At each LC tank, a transformer is connected to form a buffer. An oscillating signal is output through the buffer with no power consumption. Additionally, a capacitor is connected to the secondary coil of the transformer to form a bandpass filter, thereby attenuating a harmonic signal included in the oscillating signal.

Abstract: A differential type VCO (Voltage Controllable Oscillator) is disclosed. The VCO has a differential amplifier having a couple of transistors and a couple of LC tanks. At each LC tank, a transformer is connected to form a buffer. An oscillating signal is output through the buffer with no power consumption. Additionally, a capacitor is connected to the secondary coil of the transformer to form a bandpass filter, thereby attenuating a harmonic signal included in the oscillating signal.

Abstract: Compounds are provided which have the structure 1

Abstract: Compounds are provided which have the structure 1

Abstract: Compounds are provided which have the structure 1

Abstract: Compounds are provided which have the structure 1

Abstract: Disclosed is a method for producing an SiC preform of a high volume fraction used for the manufacture of a metal matrix composite. The method involves the steps of mixing SiC particles of different particle sizes each selected from a range of 0.2 to 48 &mgr;m with an organic binder, an inorganic binder, an aggregating agent, and distilled water, thereby producing a mixture, and stirring the mixture in accordance with a ball milling process, thereby producing a slurry containing the SiC particles, pouring the slurry containing the SiC particles into a mold having upper and lower molds respectively provided with absorbent bodies, and squeezing the slurry in the mold, thereby reducing a residual moisture content of the slurry, completely drying the slurry reduced in residual moisture content, thereby producing an SiC preform, and calcinating the SiC preform. The preform is impregnated with a metal matrix while maintaining a high reinforcement volume fraction of 70 vol % or more.

Abstract: Compounds are provided which have the structure wherein Q is C or N, A is 0 or S, Z is O or a bond, X is CH or N and R1, R2, R2a, R2b, R2c, R3, Y, x, m, and n are as defined herein, which compounds are useful as antidiabetic, hypolipidemic, and antiobesity agents.

Abstract: The present invention relates to a method of preparing a preform with a high volume fraction of SiC particles. A slurry containing SiC particles and binders is ball-milled and pressed in an apparatus to give a primary preform. This primary preform is dried at room temperature and then, at a high temperature. The dried primary preform is subjected to calcination to prepare the preform. In the apparatus, which comprises a bottom die; a top mold with a cavity, placed on the bottom die, an upper punch for pressing a material for the preform in the cavity; and two water-absorbers, one being inserted between the bottom die and the top mold, the other being placed on the top mold, the slurry is introduced in the cavity and pressed by the punch while the water is absorbed in the absorbers or drained through a gap between the bottom die and the top mold, thereby improving the volume fraction of SiC particles.