摘要:
An ultrasonic imaging apparatus and method of forming an image of an acoustic image of an object employing the aperture synthesis technique, in which at least one partial aperture for accommodating a predetermined number of successive transducers is established and applied to a transducer array to select the predetermined number of successive transducers accommodated in the partial aperture so that the selected transducers serve to transmit ultrasonic acoustic signals to an object and receive signals reflected from the object, and the at least one partial aperture is specifically moved along the arrayed transducers for similar signal transmission to and/or signal reception from the object, whereby the apparatus and the method do not suffer substantial noise caused during changeover between transmitting and receiving operation modes and/or enjoy and enlarged aperture for signal transmission or enlarged aperture for signal reception with a suppressed decrease of the frame rate.
摘要:
In NMR spectrometers, a probe coil has been disposed close to a sample that is placed in a uniform polarizing magnetic field. Conventionally, this coil has comprised several turns which are wound on the curved surface of a cylindrical sample region. The present invention provides a probe coil having an odd number of turns and capable of detecting signals with high sensitivity. The probe coil can be made to have an inductance best suited to the purpose of the observation.
摘要:
In a tract wire tightening device for a carriage of a printer, a wire connected to the carriage is looped around pulleys. A motor to drive the wire is movable with respect to a base. A spring is interposed between the motor and the base so as to bias the pulley which is interlocked with the motor.
摘要:
A sacrificial brazing fin stock for use in an aluminum base alloy heat exchanger comprises an aluminum base alloy core having a grain size of 100 .mu.m or more and consisting essentially of 0.5 to 2 wt. % manganese plus iron, said manganese being more than iron, 0.1 to 0.7 wt. % zinc, 0.001 to less than 0.02 wt. % tin, and balance aluminum and a cladding consisting of one material selected from an Al-Si base alloy and an Al-Si-Mg base alloy.The above fin stock protected a main tube of the heat exchanger from a pitting corrosion and led to a greatly expanded use of the aluminum base alloy heat exchanger.
摘要:
1-Halogenotricyclo [4.3.1.1.sup.2,5 ] undecanes are prepared by reacting tricyclo [4.3.1.1.sup.2,5 ] undecane with bromine or by reacting tricyclo [4.3.1.1.sup.2,5 ] undecane-1-ol with thionyl halide. The compounds are useful intermediates for preparing 1-aminotricyclo [4.3.1.1.sup.2,5 ] undecane hydrochloride which has antiviral activity.
摘要:
8-EXO-HYDROXYMETHYL-ENDO-TRICYCLO [5.2.1.0.sup.2,6 ] DECANE IS PREPARED BY HYDROGENATING 8- AND 9-EXO-FORMYL-ENDO-TRICYCLO [5.2.1.0.sup.2,6 ] DECA-3-ENES.
摘要:
4-HOMOISOTWIST-3-YL-CARBINOL HAVING THE FORMULA (II): ##STR1## is prepared by reducing 4-homoisotwistane-3-carboxylic acid or a salt or lower alkyl ester thereof, having the formula (I): ##STR2## wherein A is hydrogen, one equivalent of an alkali metal or an alkaline earth metal, or an alkyl group having 1 to 8 carbon atoms.
摘要:
A method for manufacturing a polycrystalline silicon ingot includes unidirectionally solidifying a molten silicon upwardly from the bottom of a crucible, wherein the crucible is provided with silica deposited on the bottom of the crusible; and then dividing the degree of solidification in the crucible into a first zone from 0 mm to X in height (10 mm≦X
摘要:
A layer forming device forms a layer of liquid absorbing particles on a surface of a layer of a hardenable solution capable of being hardened in response to a given stimulus so that the liquid absorbing particles absorb liquid drops supplied to the surface of the layer of the hardenable solution.
摘要:
A reciprocating compressor having an aperture control valve for an inlet passage. Sectional area of the inlet passage is maintained near the outlet holes of the aperture control valve, distribution of flow rates of refrigerant gas drawn into the cylinder bores during inlet stroke is even. A cylinder block is provided with cylinder bores, a valve plate opposing one end of the cylinder block having inlet and outlet hole pairs, and a cylinder head forming an annular outlet chamber and a cylindrical inlet chamber radially inside the outlet chamber. The cylinder head has an inlet passage and an outlet passage, and an aperture control valve with an inlet hole connecting with the inlet passage and outlet holes controlling the aperture of the inlet passage. The aperture control valve is disposed in the inlet chamber.