Abstract: A process for preparing an optically active 1,4-bridged-cyclohexane carboxylic acid derivatives which are clinically important thromboxane A.sub.2 thromboxane of formula (IV): ##STR1## wherein, R is phenyl or phenyl substituted with hydroxy, lower alkoxy, halogen, or lower alkyl; Y is oxygen, methylene, substituted methylene; m is 0 or 1; n is 0, 1 or 2; q is 3 or 4 with the proviso that when m is 1, n is 0 or 1 from an optically active norbornyl amine derivative.

Abstract: A receiver has a plurality of receiving systems connected to a plurality of antennas, respectively, and a selective switching circuit for carrying out selective switching between output signals from the plurality of receiving systems to output an output signal from a receiving system in the most satisfactory receiving state, wherein the selective switching circuit has a fuzzy inference operation unit for discriminating receiving states of respective receiving states by a fuzzy inference. Accordingly, it is possible to synthetically judge the receiving state of the receiver to easily and stably select the optimum receiving system in the receiver.

Abstract: A windshield antenna for a vehicle is mounted on a central portion of a window glass of the vehicle. The heating wires serve both as a window defogger element and as an antenna for receiving amplitude-modulated (AM) waves. A pair of first and second antenna elements are disposed on right and left sides of the heating wire, each of the first and second antenna elements serving as an antenna for receiving frequency-modulated (FM) waves. These antenna elements can be the same size, yielding improved diversity reception characteristics.

Abstract: A high frequency, negative feedback amplifier is coupled at its input to an inductance network which together with the input capacitance of the negative feedback amplifier forms a resonance circuit. The resonance frequency of the resonance circuit is set within the desired reception band of the amplifier, to thereby form a band pass filter having a pass band corresponding to the desired reception band. The resonance circuit assures only a real input to the amplifier thereby reducing the input noise attributable to the input source.

Abstract: A space diversity system capable of operating accurately over a wide range of received input electric field strengths. With a middle or high received electric field strength, a search operation for the antenna with the highest strength is commenced in response to noise detected in the output of the antenna presently selected. With a low received electric field strength, the search operation is carried out in response to noise such as white noise at all times.

Abstract: A method for the preparation of polyurethane elastomers in which polyethyleneglycol-bis(4-aminobenzoate) is used as the curing agent to be admixed with the polyurethane formulations. This curing agent imparts considerably extended pot life to the ready-prepared polyurethane composition to be cured by heating into an elastomer having improved properties.

Abstract: 4-Chloro-3,5-diaminophenyl acetates having the formula ##STR1## wherein R represents an alkyl group are useful as curing agent for polyurethane elastomer and intermediates for pharmaceutical and agrochemical compounds and are produced by simultaneously nitrating hydrolyzing 4-chlorobenzylcyanide and esterifying the resulting 4-chloro-3,5-dinitrophenyl acetic acid and then reducing the resulting ester.

Abstract: A curing agent for polyurethane which has a melting point at most 110.degree. C and comprises a mixture of at least two compounds of the general formula: ##STR1## Wherein n is zero or a positive integer. This curing agent has a low solidifying point and good solubility in solvents and thus is excellent in workability. This curing agent is used for the production of polyurethane highly stabilized in quality.