Abstract: In an exhaust gas purifying apparatus including first and second exhaust converters composed of a honeycomb catalytic substrate, arranged in sequence from an exhaust manifold downstream along exhaust gas flow of an engine, wherein the catalytic substrate of the first converter has a heat capacity of not exceeding 0.5 J/K per 1 cm.sup.3 in temperatures ranging from room temperature up to 300.degree. C., and the catalytic substrate of the second converter has a geometric surface area of at least 25 cm.sup.2 /cm.sup.3. The first converter purifies exhaust gas immediately after starting up and before completion of warming up of the engine, and the second converter further purifies noxious contents still remaining as being beyond capacity of the first converter.

Abstract: A curved honeycomb structural body having a number of through holes penetrating along a direction in which the honeycomb structural body is curved. Pitches between adjacent interior partition walls defining through holes are set smaller on a radially outer side of a curved portion than on a radially inner side thereof.

Abstract: A ceramic precombustion chamber construction for an internal combustion engine including a precombustion chamber formed by a ceramic body to be inserted in a precombustion chamber receiving cavity of a metal cylinder head. Projections are formed on an outer circumferential surface of a metal sleeve fitted on the ceramic body, or on an inner circumferential surface of the precombustion chamber receiving cavity of a metal cylinder head, or on an outer circumferential surface of the ceramic body. Thermal insulating spaces are formed by the projections and the inner circumferential surface of the precombustion chamber receiving cavity or the outer circumferential surface of the metal sleeve or the outer circumferential surface of the ceramic body. One of the projections is formed with a glow-plug receiving aperture which communicates with a glow-plug receiving aperture formed in the precombustion chamber receiving cavity of the metal cylinder head.

Abstract: A cylinder head has a ceramic precombustion chamber for an internal combustion engine. The cylinder head includes a part of the cylinder head made of a ceramic body having an injection aperture communicating with a main combustion chamber for jetting burning gases therethrough, a metal sleeve fitted on an outer circumference of the ceramic body and fitted in a precombustion chamber insert bore forming part of the cylinder head, and a head gasket interposed between the cylinder block forming the main combustion chamber and the ceramic body, the metal sleeve and the cylinder head. A surface of the ceramic body facing to the head gasket extends onto a side of the main combustion chamber beyond a surface of the ceramic body opening the injection aperture into the main combustion chamber.

Abstract: A sustained-release particulate preparation having a controlled releasing rate of a pharmacologically active agent contained therein in the living body, and a process for preparing the preparation are disclosed. The preparation comprises a polymeric compound which is capable of being degraded in the living body and which is compatible with living tissue, a pharmacologically active agent, and a natural high molecular weight compound of sugar origin or a derivative thereof. The preparation has fine and uniform particle size and can be administered subcutaneously or intramuscalarly for obtaining a long-lasting pharmacological activity.

Abstract: A precombustion chamber construction for an internal combustion engine comprises a precombustion chamber constructed by a ceramic body having a glow-plug receiving aperture to be inserted in a precombustion chamber receiving cavity of a metal cylinder head. A metal sleeve may be fitted on the ceramic body. A seat is formed at an entrance of a glow-plug receiving aperture on an outer circumferential surface of the metal sleeve, thereby preventing any leakage of burnt gases to ensure the complete thermal insulating effect. The metal sleeve is not necessarily needed. In this case, the seat is formed at an entrance of the glow-plug receiving aperture on an outer circumferential surface of the ceramic body.

Abstract: A ceramic precombustion chamber for an internal combustion engine such as a diesel engine consists of a metal ring and a ceramic body fitted in the metal ring by shrinkage fit. The ceramic body has a through-aperture for an injection nozzle and a combustion gas injection aperture. A shrinking allowance at a lower portion of the ceramic body with the metal ring is smaller than that an upper portion of the ceramic body with the metal ring, thereby decreasing surface pressures at the lower portion of the ceramic body to prevent cracks which would occur in the lower portion caused by surface pressures resulting from the shrinkage fit.

Abstract: A ceramic precombustion chamber construction of an internal combustion engine includes at least one ceramic body having a circular cross-section, a metal ring in which the ceramic body is fixed by shrinkage fitting, and at least one key interposed between the ceramic body and the metal ring for preventing rotation therebetween. Contour lines of a key receiving notch formed in an inner circumference of the metal ring are positioned on inner sides of contour lines of a key receiving notch formed in an outer circumference of the ceramic body. With the arrangement, the ceramic body is prevented from loosening from the fitting with the metal ring due to heat and vibration in use and is prevented from being damaged resulting from cracks occurring in the ceramic body.

Abstract: A method of dynamically balancing an assembly of a metal jig and a ceramic rotor attached thereto, the ceramic rotor having a shaft portion, and the metal jig having at its one axial end a fixing hole, comprising the steps of: inserting the shaft portion of the ceramic rotor into the fixing hole of the metal jig, and thereby fixing the ceramic rotor to the metal jig to provide the assembly; and dynamically balancing the assembly by fixing at least one balancing piece in at least one of a plurality of balancing holes which are formed in the metal jig, the balancing holes being open in an outer surface of the metal jig. Also disclosed is a metal jig of a generally cylindrical shape for rotating a ceramic rotor in a dynamically balanced condition, having a fixing hole in its one axial end portion, in which a shaft portion of the ceramic rotor is inserted and fixed.

Abstract: An oscillator of a pulse generator for use in a system for refreshing a dynamic memory comprises an operational amplifier having first and second input terminals and an output terminal, a thermistor connected between the first input terminal and the output terminal, a capacitor connected between the first input terminal and a ground, and four resistors. A first resistor is connected between the second input terminal and the output terminal. A second resistor is connected between the second input terminal and the ground. A third resistor is connected between the second input terminal and a power supply. A fourth resistor is connected between the output terminal and power supply.

Abstract: A signal generator generates different input signals when the keys are depressed. The signal generator comprises an input signal generating circuit and a double-key-depression detecting circuit. The input signal generating circuit includes a shift register having a plurality of shift stages and the associated output lines, signal lines for transmitting signals which may be sequentially derived from the output lines of the shift stages, and a discriminator for discriminating through which signalline is transmitted the signal.Each output of the shift stages of the shift register provides one information representative of a depressed key. Output of the discriminator provides another information representative of a depressed key. The input signal is identified by the combination of two kinds of the information.

Abstract: A compact electronic calculator having the function of extracting cubic roots comprises a first register for storing therein a number, a circuit for dividing the number in the first register at every three digits and effecting subtraction therefrom, and a second register for storing therein the data provided by the dividing circuit.

Abstract: A calculator of the type having parenthesis keys, wherein there is provided means for performing an operation on an expression containing an exponent term or terms by touching keys in the left-to-right sequence as the expression reads.

Abstract: An electronic calculator having a pair of parenthesis keys is capable of displaying a temporary partial result obtained from an operation performed on a portion of a numerical expression to be calculated, which portion is included within a pair of parentheses. The partial result may be continuously displayed until the next key operation is executed. A temporary result from an exponent term in an expression is also indicated visually.