Abstract: A thermal expansion-absorbing structure for piping, which is attached to a pipe end, is provided. A semicircular form of torus shell is joined to a cylindrical form of short double pipe to define together a U-shaped longitudinal section, which is deformed due to the expansion or contraction displacement of the pipe, thereby absorbing thermal expansion. This achieves a piping reduction, compactness of a reactor building and a reduction in the construction cost of a fast reactor plant, and ensures great safety.

Abstract: A piezoelectric vibrator includes a thin quartz plate portion for generating vibrations, and non-contact electrodes for applying an alternating electric field. The electrodes are arranged on opposing sides of the thin quartz plate portion so as to not contact with the thin quartz plate portion. The electrodes may be formed on a supporter which can be bonded directly to the thin quartz plate. The electrodes may also be formed above the thin quartz plate and supported by the plate outside the thin quartz plate portion. The piezoelectric vibrator has a superior Q of resonance at high frequencies.

Abstract: Provided is a Rydberg atom impact type ion source in a mass spectrometric apparatus wherein gaseous sample molecule is impinged on Rydberg atom to ionize the sample and thus-ionized sample is subjected to mass spectrometric analysis, said ion source being characterized in that a needle rod-like grid is used in a Rydberg atom generating portion of an ion source block.

Abstract: Antenna sharing device used for a communications system such as a land mobile radiotelephone which has a transmitting frequency and a receiving frequency that are different from each other, and which commonly uses the antenna transmission and reception. The bands of transmission and reception of the antenna sharing device are each divided into half and are switched into a pair of sending side low-pass filter and a receiving side low-pass filter and a pair of sending side high-pass filter and a receiving side high-pass filter by a switching device, whereby the band widths of transmission and reception are narrowed and the isolation point is increased between the transmission and reception.

Abstract: A quartz vibrator mounted on a terminal substrate member having a through-hole. The ratio of through hole area being from 0.5 to 0.8 of the vibrators electrode area. Fine frequency adjustment is obtained by evaporation of material thru the through hole.

Abstract: A damped piezoelectric ceramic resonator. The resonator is a thin flat plate of piezoelectric ceramic material which has parallel major planar surfaces and is polarized in one direction in such a way that said direction is at an angle of from 0.degree. to 60.degree. with respect to said major surfaces, the thickness dimension of said plate being such as to impart thereto a resonance of vibrations in a thickness-shear mode at a particularly selected frequency higher than one megacycle. Operating electrodes are applied to said major planar surfaces. Vibration damping means is attached tightly to the contour of the edge of said flat plate so as to suppress unwanted resonance vibrations in said flat plate during operating. The vibration damping means is a ring of a rubber material having a hardness from 20 to 70 on the Shore A Scale and is under a tension of 20-500 gm/cm.

Abstract: This invention provides a surface elastic wave device constituted by a unitary body of a piezoelectric plate having a pair of transducers thereon, which unitary body is embedded in a casing, and wherein the wave propagation of a surface elastic wave generated on the surface of the piezoelectric plate during excitation of the device is prevented from being transferred to the casing by a thin film inserted between the casing and the wave propagation surface of the piezoelectric plate or by using as the casing a roll of flexible sheet which has the same function of wave propagation prevention as that of the thin film. This device is advantageous because it has a low spurious signal level without incrementing insertion loss, is easy to manufacture and is inexpensive. This invention also provides an effective method of making the device.

Abstract: Crystalline N.sup.6,2'-O-dibutyryl-adenosine-3',5'-cyclic monophosphate monosodium salt (DB.sub.c -AMP-N.sub.a), and a process for producing the same which may comprise the step of causing at least one solvent selected from an ether, ketone, and an ester, constituting a crystallizing organic solvent, to contact an alcoholic solution, aqueous alcoholic solution, or a simple aqueous solution of DB.sub.c -AMP-N.sub.a or may comprise the step of dissolving crude crystalline or amorphous DB.sub.c -AMP-N.sub.a in a mixture of an alcoholic solvent and the crystallizing organic solvent.

Abstract: A frequency discriminating apparatus is constituted by a piezoelectric ceramic resonator, a reference capacitor, a pre-amplifier including a broad tuning circuit, a pair of amplitude detectors, and a differential amplitude limiter. The piezoelectric ceramic resonator is made of a piezoelectric lead titanate ceramic plate having a pair of electrodes covering the entire area of the major surfaces thereof, and the plate is poled with a poling field of not less than 50 kV/cm in the thickness direction. The thickness of the plate is chosen so as to cause the plate to vibrate in the thickness-extensional vibration of the 3rd harmonic overtone at a preselected frequency when an electrical signal is applied to the pair of electrodes. The differential amplitude limiter differentially adds the two signals detected by the two amplitude detectors and limits the peak output voltage amplitudes to a predetermined amplitude.

Abstract: A piezoelectric device comprisng a thin plate of a piezoelectric material which has a Poisson's ratio of less than one-third, and has an electrode region and a non-electrode region, wherein the thickness relation between the electode region and the non-electrode region is arranged so that the thickness of the electrode region is smaller than the thickness of the non-electrode region when a value of equations represented by (.pi.p/4)+(4/k.sup.3)cot(.pi.kp/2) Q for the thickness-extensional mode, and (.pi.q/4)+(4/k)cot(.pi. q/2k) Q for the thickness-shear mode is negative respectively for a desired vibratory mode, and that the thickness of the electrode region is larger than the thickness of the non-electrode region when the value of the above equations are positive respectively for a desired thickness vibration mode.