Abstract: A microwave heating apparatus comprises a heating chamber, high frequency radio wave generator and heating resistors selectively connected through first and second switches to a power supply, and a control circuit connected through the first switch to the power supply. The heating apparatus also comprises heating resistor coupling units each including a displaceable member and a third switch. The displaceable member is displaced when the heater end is inserted into a predetermined position of the coupling unit. The third switch is closed when this displaceable member is displaced. This third switch is connected in series between the first switch and the control circuit. The high frequency radio wave generator or the heater is not connected to the power supply unless the heater end is completely connected to the heater coupling unit. Accordingly, it can prevent external leakage of the radio wave, dielectric breakdown accident or the like.

Abstract: An optically active .alpha.-cyano-3-(4-halogenophenoxy)-benzyl 2-(4-chlorophenyl)isovalerate, which consists substantially of or is rich in (S)-.alpha.-cyano-3-(4-halogenophenoxy)benzyl (S)-2-(4-chlorophenyl)isovalerate; a method for preparing the same; and an insecticidal and/or acaricidal composition containing the same.

Abstract: A mixture of stereoisomers of an .alpha.-cyano-3-(4-halogenophenoxy)benzyl 2-(4-chlorophenyl)isovalerate, which consists substantially of or is rich in an enantiomer pair of an (S)-.alpha.-cyano-3-(4-halogenophenoxy)benzyl (S)-2-(4-chlorophenyl)isovalerate and an (R)-.alpha.-cyano-3-(4-halogenophenoxy)benzyl (R)-2-(4-chlorophenyl)isovalerate; a process for preparing the same; and an insecticidal and/or acaricidal composition containing the same.

Abstract: An apparatus for forming a cloud of magnetic toner particles has a rotatable magnet roller with a number of magnetic poles disposed within a non-magnetic cylindrical sleeve. Magnetic toner particles are supplied from a hopper onto the sleeve. A magnetic bar is disposed above the sleeve. The rotation of the magnet roller causes the sleeve to carry magnetic toner particles thereon. When the magnetic toner particles carried approach to the magnetic bar, those become in a cloudy state.

Abstract: This invention relates to novel compounds of the general formula (I): ##STR1## wherein A represents ##STR2## in which B represents a ring-forming residue of a 5- or 6-membered carbon-containing heterocycling ring containing at least one nitrogen atom and which may further contain an oxygen atom in the ring, and R.sub.1 and R.sub.

Abstract: An .alpha.-cyano-3-phenoxybenzyl 2-(4-chlorophenyl)isovalerate which consists substantially of or is rich in (S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-(4-chlorophenyl)isovalerate and (R)-.alpha.-cyano-3-phenoxybenzyl (R)-2-(4-chlorophenyl)isovalerate. A method for preparing the same and an insecticidal and acaricidal composition.

Abstract: A process for racemization of optically active phenylacetic acid derivatives, which comprises heating an optically active phenylacetic acid derivative of the formula (I): ##STR1## wherein X and Y, which may be the same or different, each represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a halogen-substituted lower alkyl group or a halogen-substituted lower alkoxy group, or X and Y may jointly form an alkylenedioxy group; m and n, which may be the same or different, each represents an integer of 1 to 5, and the sum of m and n does not exceed 5; and R represents an isopropyl group or a cyclopropyl group, to a temperature of at least 150.degree. C. in the presence or absence of an inert solvent.

Abstract: A magnetic brush apparatus is provided with a hopper for supplying powdered one-component magnetic developer to a cylindrical sleeve housing a rotating magnet roller with a number of magnetic poles. The powdered magnetic toner supplied onto the sleeve surface is formed into a magnetic brush on the sleeve surface under control of alternating magnetic field generated by the magnet roller. The magnet brush is carried around the sleeve surface with rotation of the magnet roller. Outside the sleeve surface a predetermined distance is positioned a magnetic member which may be attached to the tip end of a doctor blade. The magnetic member disturbs the alternating magnetic field on the sleeve surface, thereby restricting the height of the powdered developer passing between the end of the magnetic member and the sleeve surface.

Abstract: Disclosed herein is a system for controlling an ignition timing of an internal combustion engine in its idle condition. A control chamber of a vacuum advancer for operating a distributor of the engine is connected, via a vacuum modulator valve formed as a double diaphragm mechanism, to a vacuum signal port formed in an intake passageway of the engine at a position downstream of a throttle valve in its idle position. The vacuum modulator is adapted to control the vacuum level at the control chamber of the advancer to be reversely proportional to the vacuum level at the vacuum signal port. Accordingly, a stable idle operation of the engine can be obtained.

Abstract: An oxide-coated cathode for electron tubes which comprises a base metal plate made of an alloy comprising nickel as a main component and 2% by weight or more of at least one high-melting point metal, an oxide layer coated on the base metal plate comprising at least one oxide of a reducing element, a carbon coating layer coated on the oxide layer, and an alkaline earth oxide layer capable of emitting electrons coated on the carbon coating layer can maintain electron emitting life for a long period of time due to the prevention of interfacial reaction between the base metal plate and the alkaline earth oxide layer by the oxide layer and the carbon coating layer.

Abstract: A pressure control valve assembly comprising a rubber diaphragm to which is applied the negative pressure of the engine intake manifold and the exhaust gas pressure of the engine exhaust manifold. The diaphragm of the present invention is formed with a gradual descent sloping down from a valve-actuating central portion to an outer periphery. Adjacent to one portion of the outer periphery of the diaphragm a port opening to the outside of the valve assembly is provided. Thus, any gas ingredients such as condensed water can be expelled along the descent of the diaphragm via the port without gathering on the diaphragm surface which will therefore be free from objectionable oxidation or corrosion.

Abstract: In a coated metal structure comprising a metal substrate and a coating layer of a thermoplastic polyester resin heat-bonded to the metal surface, the polyester resin has a relative viscosity of 1.2 to 1.8 as measured at 25.degree. C. in o-chlorophenol at a concentration of 0.5 g/100 ml and the tack point of the polyester resin is not lower than 130.degree. C. and the degree of crystallinity of the polyester resin is up to 30%.This structure has improved peel resistance and is excellent in mechanical and chemical properties, especially adaptability to shaping processing and corrosion resistance. This structure can easily be formed into various vessels and containers and closure means of vessels and containers by such processing as drawing and ironing. This structure provides shaped articles excellent in peel resistance, corrosion resistance and processability.

Abstract: A pressure sensitive adhesive tape comprising a backing and a pressure sensitive adhesive layer, wherein the backing is produced by stretching a long sheet composed of polypropylene as a main component in the substantially transverse direction, the backing having the properties that the shock edge tearing resistance is below 200g, the elongation at break is above 200% in the lengthwise direction, the tensile strength is above 170 kg/cm.sup.2 in the lengthwise direction and above 800kg/cm.sup.2 in the transverse direction and the impact strength is above 15kg.cm/mm.sup.2 in the lengthwise direction and above 40kg.cm/mm.sup.2 in the transverse direction, and the backing having a thickness of about 10 to 300 microns.

Abstract: An apparatus is provided for introducing secondary air for into an internal combustion engine. The apparatus has an air pump coupled to an air injection pipe system, the latter having an end terminating upstream of the catalytic converter, for introducing an amount of secondary air into the exhaust system of the engine. The apparatus further includes a valve device for maintaining the secondary air directed to the exhaust system from the air pump at determined constant pressure; thus, the amount of secondary air introduced into the exhaust system is effectively decreased during high rotational speed engine operation in order to prevent the catalytic converter from being overheated.

Abstract: A sulfonated product of butadiene or isoprene oligomer of the formula: ##STR1## wherein one of R.sub.1 and R.sub.1 ' is hydrogen or methyl and another one is hydrogen; R.sub.2 ' is hydrogen or methyl; one of X.sub.1 and X.sub.2 is --SO.sub.3 M and another one is hydrogen; a and b are each an integer satisfying the conditions; n = a + b, 2 < n < 40 and 0 < b; M is hydrogen, Na, K, Li or --NR.sub.3 R.sub.4 R.sub.5 R.sub.6 ; and R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each hydrogen or an alkyl having 1 to 6 carbon atoms, which has specific properties, particularly excellent hard water resistance, and is useful for various utilities, for instance, as a surfactant, emulsifier, or the like, and a process for the production of the sulfonated product.

Abstract: A differential circuit including in a monolithic semiconductor chip a pair of differential amplifying elements having each one electrode connected in common and to a common diode means and respective input and output electrodes, another diode means connected to the output electrode of one of said amplifying elements, one transistor having an input signal electrode connected to one end of said common diode means to allow the passage of a current of half the magnitude of that through said common diode, another transistor having an input signal electrode connected to one end of said another diode means to allow the passage of a current of equal magnitude as that through said another diode means, and an output terminal connected to said one and another transistors.

Abstract: This application discloses an EGR system in which the vacuum control valve is improved to comprise:A first diaphragm;A second diaphragm;A first chamber which is formed outside said first diaphragm and communicating with the atmosphere;A second chamber which is formed between said first and second diaphragm and communicating with the pressure control chamber of the EGR valve, and;A third chamber which is formed outside said second diaphragm and communicating with the intake pipe of the engine at the downstream of the throttle valve of the carburetor.

Abstract: A radio-frequency automatic gain control circuit wherein at the time of a weak field input, the input signal is amplified by a differential amplifier, and at the time of an intense field input, the differential amplifier is operated as a grounded-emitter amplifier.

Abstract: An FM multiplex demodulator circuit comprises, within a semiconductor integrated circuit, a double balance type synchronous detection circuit which includes load elements formed within the semiconductor integrated circuit, a pair of negative feedback type differential amplifier circuits which amplify a pair of detection outputs from the detection circuit and also perform de-emphasis thereof, respectively, and a pair of emitter follower circuits which are connected to outputs of the negative feedback type differential amplifier circuits, respectively.

Abstract: In a receiver comprising a radio frequency amplifier stage, a frequency converter stage, an intermediate frequency amplifier stage and a detector, so that the gains of the radio frequency amplifier stage and the intermediate frequency amplifier stage are automatically controlled by an AGC voltage derived from the detector, the improvement further comprising a voltage comparator which compares a signal amplitude value of the radio frequency amplifier stage and a predetermined reference value and which provides a detection output signal when the former value becomes greater than the latter value, the gain of the radio frequency amplifier stage being reduced by the detection output signal so as to prevent the output clipping of the radio frequency amplifier stage.