Abstract: In a resin molded controlled-release product which comprises a volatile or elutable active agent dispersed in a substantially transparent and inert resin molded material, the improvement which comprises a colored material located inside or on the back surface of the molded product which is not visible through the product at the initial concentrations of the active agent, but is visible through the resin product at concentrations of the active agent at which the activity of the product is substantially extinct.

Abstract: A photosensitive composition containing the 2-trihalomethyl-5-aryl-1,3,4-oxadiazole compound represented by the following general formula: ##STR1## wherein X represents a chlorine atom or a bromine atom and A represents a phenyl group, a naphthyl group or a phenyl or naphthyl group substituted by a halogen atom, an alkyl group, an alkoxy group, a nitro group, a cyano group or a methylenedioxy group.

Abstract: An automatic hydraulic tappet for taking up clearance between a cam and a valve stem in an internal combustion engine with an overhead camshaft can rapidly attain its optimum operational efficiency when the engine is started, since the supply conduit, which supplies engine lubricating oil to an annular groove communicating with a chamber between two tappet members, is provided with a sump which is lower than the groove and, therefore, acts as an oil reservoir when the engine is stopped.

Abstract: Discoloring and fading of silver halide color photographic materials are effectively prevented by incorporating a compound of the formula (I) or (II) in a silver halide photographic layer thereof ##STR1## wherein A represents an aryl group; R.sub.1, R.sub.2 and R.sub.3 each represents hydrogen, a halogen atom, an alkyl group, or an aryl group, except that R.sub.1, R.sub.2 and R.sub.3 cannot all be hydrogen atoms; R.sub.4 and R.sub.5 each represents hydrogen, a halogen atom, an alkyl group, an aryl group, an alkoxy group, an alkylthio group, an acyl group, an aryloxy group, a carboxy group, a sulfo group or a hydroxy group; and R.sub.6 and R.sub.7 each represents hydrogen, a halogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkylthio group, an acyl group, or a hydroxy group; or R.sub.6 and R.sub.7 together form an ##STR2## group or a 5-membered or 6-membered carbocyclic or heterocyclic ring.

Abstract: In a method for electrolyzing hydrochloric acid in an electrolysis apparatus, the improvement which comprises the electrolysis apparatus comprising at least two electrolysis cells, each electrolysis cell having at least one anode, at least one cathode and at least one cation exchange membrane therebetween to define an anode compartment and a cathode compartment therein, and the method comprising the steps of(a) feeding hydrochloric acid aqueous solution as a starting material into the anode compartment of a first electrolysis cell and electrolyzing the hydrochloric acid aqueous solution therein,(b) feeding hydrochloric acid aqueous solution discharged from the anode compartment of the first electrolysis cell into the anode compartment of a second electrolysis cell and electrolyzing the hydrochloric acid aqueous solution therein,(c) feeding hydrochloric acid aqueous solution discharged from the anode compartment of the last electrolysis cell of the electrolysis apparatus into the cathode compartment of each of

Abstract: An apparatus and method for separating light and heavy materials from one another. Materials to be separated are transported on a conveyer belt past a set of overhead rollers. Air is sucked through gaps between the rollers with covers surrounding groups of rollers which are coupled to a suction pump. Air is jetted through apertures in the conveyer belt to loosen adherence between lighter materials and larger articles. A high voltage is impressed upon the rollers to provide electrostatic attraction for light dry materials. The rollers may be provided with opposing protrusions which are used to pinch off certain materials.

Abstract: Connecting means for connecting the ends of at least a pair of pipes, said pipe ends being immersed in water and one of the or each pair of pipe ends being mounted on a fixed structure and connected, e.g. to an oil well, and the other of the or each pair of pipes being mounted on a movable structure, e.g. a column, mounted for oscillatory movement relative to the fixed structure, comprises in respect of the or each pair of pipes a tube of a length greater than the maximum distance between the pipe ends and in a spiral and/or helical shape, wherein the tube is supported intermediate the ends thereof solely by means for correcting the buoyancy thereof to reduce the buoyancy to substantially zero.

Abstract: The invention concerns a drill head for the attachment of bone drills or bone milling cutters, as well as the bone drills or milling cutters themselves, especially for preparing bone cavities into which enossal prosthetic elements can be inserted. The designation "bone drill" or "bone milling cutter" is meant to include all drills or cutters with which, in the field of human or veterinary medicine, including the dental field, material can be removed from teeth, bones and bone-like tissue, as well as from corresponding substitute materials. Finally the invention concerns also dental and half-implants, being particularly simply inserted with these instruments.

Abstract: A focussing lens servo driving device for an optical information reading device in which the lens is first driven towards the focussed position with a controlling servo circuit operated in an open loop mode. Once the lens has passed a predetermined position an opposition force is produced in dependance on the lens position. The opposition force is gradually reduced and the servo loop is closed when the lens has been turned back to the predetermined position so that stable operation is provided.

Abstract: A telescoping, U-shaped straight through, primary flow invert form may be lenghtened or shortened to meet the diameter of the cylindrical manhole and is mounted at opposite ends to the aligned main flow inlet and outlet pipes of the manhole. Longitudinally projecting bottom and opposed side invert tabs located at the ends of the straight through invert form contact the insides of the inlet and outlet pipes, respectively, to center the form. Slide guides, each carrying a retainer tab, adjust the retaining tabs longitudinally to position them within respective pipes at respective ends of the form for preventing lifting of the invert form during concrete pouring within the manhole. An angularly adjustable, intersecting side flow invert form projects from another pipe opening to the manhole at some angle to the straight through form and includes interlocking, axially slidable, opposed section halves.

Abstract: A cathode-ray tube image recording device for recording images on a photosensitive thermal development recording medium which may have a reduced sensitivity due to time deterioration. An image of a density wedge is exposed and developed then sensed to determine the sensitivity of the recording medium. The sensing operation produces a density identification step number which is used to set one or both of the brightness and light emission time of the cathode-ray tube in accordance with a predetermined characteristic curve or function. A switchable resistor circuit or read-only memory may be used for applying the characteristic function.

Abstract: A boot for covering the juncture between a drive shaft and a universal joint casing formed of a resilient material and having a small end portion and a large end portion with a bellows structure therebetween. The bellows has undulations with ridges and valleys with ridge angles determined such that contact between adjacent undulations when the boot is operatively connected is confined to a plane. Preferably, the thickness of the resilient material is greater in a longitudinally center portion than in the remaining portions of the bellows and the distance between neighboring ridges in the central portion is greater than in the remaining portions.

Abstract: A device for supplying air into the exhaust gases of an internal combustion engine to promote complete combustion of carbon monoxide and hydrocarbons for the reduction of atmospheric pollution has a manually operable shut-off valve held open by a spring, which can be operated by a push-button to intercept the supply of air to an air feed pipe when making test measurements on the engine or tuning the carburettor.

Abstract: This invention provides a rotor sealing device used on an open-end spinning apparatus having a spinning rotor which forms therein air-discharge apertures, the opening in said spinning rotor being openably closed by a body member which has a fibers delivery aperture formed therein; said rotor sealing device being characterized in that a sealing member is inserted into the space located between said rotor opening and said body member positioned in opposite relation thereto. This device, though being of such a simple construction, is capable of improving the effect of rotor inside sealing over devices heretofore.

Abstract: A silver halide photographic light-sensitive material having a hydrophilic organic colloid layer containing a dispersion of a substantially water-insoluble photographic additive dissolved in a phosphoric acid ester represented by the following general formula (I): ##STR1## wherein R.sub.1 represents a saturated alicyclic group; and R.sub.2 and R.sub.3, which may be the same or different, each represents a saturated alicyclic group, an alkyl group or an aryl group.

Abstract: A tractor vehicle has a driving station including a driver's seat and steering console which is mounted on a base for swivelling movement about a vertical axis through 180.degree. between a tractor configuration and a pushing power unit configuration. In the latter configuration the driving station is supported on a higher tractor cab floor level to enable the driver to see over equipment being pushed. The driving station has a support which is connected to the tractor cab floor by at least one parallelogram linkage and weight compensating springs which lift the support off the cab floor.

Abstract: A chopper type switching circuit having first and second transmission paths adapted to transmit a predetermined input signal to respective output terminals. First and second switching elements are connected respectively between the mid points of the first transmission path and a reference voltage line. A group of resistors are series connected between the output terminals. Third and fourth switching elements are connected respectively between the series connection points of the group of resistors and the reference voltage line. The first and fourth switching elements and the second and third switching elements are controlled to be alternately rendered conductive and non-conductive.

Abstract: A method is disclosed for the preparation of implants, especially dental implants, from ceramic substances having in particular a porous surface which stimulates ingrowth of bone tissue.

Abstract: A process for producing a flame resistant rigid polyurethane foam by reacting a reaction mixture comprising a polyetherpolyol and/or a polyesterpolyol having an active hydrogen atom, a polyisocyanate, water and/or a volatile foaming agent and an emulsifying agent, in which a specific amine compound shown by the general formula as defined hereinafter in the specification is added to the reaction system, the weight ratio of amine compound to polyetherpolyol and/or polyesterpolyol being from 70:30 to 30:70, and also the flame resistant rigid polyurethane foam produced by the process.