Abstract: The invention relates to a method for the oxidation of a primary or secondary alcohol, preferably to form an aldehyde or ketone, comprising the following steps: a) providing a catalyst composition comprising at least one compound containing a nitroxyl radical, at least one NO source, at least one carbon or mineral acid or an anhydride of a carbon or mineral acid; b) producing a reaction mixture by adding at least one primary or secondary alcohol and a gas comprising oxygen and optionally one or more than one solvent to the catalyst composition from step a) or step e); c) incubating the reaction mixture from step b) at a temperature of between 0 and 100° C. or at the boiling point of the solvent; d) simultaneously with or subsequent to step c): crystallizing the reaction product; and e) recovering the catalyst composition by removing the crystallized reaction product from the reaction mixture obtained in step d).

Abstract: The invention relates to a method for the oxidation of a primary or secondary alcohol, preferably to form an aldehyde or ketone, comprising the following steps: a) providing a catalyst composition comprising at least one compound containing a nitroxyl radical, at least one NO source, at least one carbon or mineral acid or an anhydride of a carbon or mineral acid; b) producing a reaction mixture by adding at least one primary or secondary alcohol and a gas comprising oxygen and optionally one or more than one solvent to the catalyst composition from step a) or step e); c) incubating the reaction mixture from step b) at a temperature of between 0 and 100° C. or at the boiling point of the solvent; d) simultaneously with or subsequent to step c): crystallizing the reaction product; and e) recovering the catalyst composition by removing the crystallized reaction product from the reaction mixture obtained in step d).

Abstract: The invention relates to a method for producing 2,6-dioxabicyclo-(3.3.0)-octane-4,8-dione (I), comprising the oxidation of dianhydrohexitols (II-IV), or of corresponding hydroxy ketones, with an oxygen-containing gas in the presence of a catalyst composition, the reaction proceeding without the addition of halogen sources.

Abstract: The invention relates to a method for producing 2,6-dioxabicyclo-(3.3.0)-octane-4,8-dione (I), comprising the oxidation of dianhydrohexitols (II-IV), or of corresponding hydroxy ketones, with an oxygen-containing gas in the presence of a catalyst composition, the reaction proceeding without the addition of halogen sources.

Abstract: The invention relates to a method for producing aldehydes and ketones from easily accessible primary and secondary alcohols by oxidation with atmospheric oxygen or pure oxygen using a catalyst system which consists of a derivative of a free nitroxyl radical.

Abstract: A driver for a matrix display successively stores digital data codes. During a first time interval, the driver charges a capacitor coupled to its output to a voltage level represented by the most-significant bits of a stored data code. During a second time interval, the driver shifts the voltage on the capacitor by a magnitude represented by the least significant bits of the stored data code.

Abstract: An illumination system and method for illuminating an output patch includes a first array for receiving light, and which includes first lenslets. A second array, which includes second lenslets, receives the light from the first array and outputs the light to the illumination patch. The first lenslets have a uniform shape and the second lenslets have a non-uniform shape thereby reducing optical extent and maximizing system lighting efficiency.

Abstract: A color television system for transmitting a color television signal, specifically for recording on and subsequently reproducing from a record carrier. The color television signal to be transmitted contains a first carrier which is frequency-modulated with the luminance information and a second carrier which is modulated with the chrominance information, whose frequency lies between zero and the first-order lower side band of the modulated first carrier which corresponds to the highest modulation frequency. Said second carrier does not have a fixed frequency, but is locked to the instantaneous frequency of the modulated first carrier by a constant integral ratio. Depending on the characteristics of the transmission medium and the signal processing equipment said ratio is preferably two or three.

Abstract: An apparatus for reading a disc-shaped record carrier on which information is stored in a preferably spiral-shaped track. Said information is read optically with the aid of a radiation beam, which via a directing system transfers the information contained in the scanning point of the record carrier to a read detector. The radial position of the scanning point is controlled with the aid of a control system which via a first pattern of radiation spots which is projected onto the record carrier receives information about said radial position and by means thereof controls the directing system. In order to ensure that the system is stable under all conditions use is made of a second pattern of radiation spots which are projected onto the record carrier, which pattern is radially shifted relative to the first pattern, and from which a control signal is derived with which the transfer function of the control system is varied so as to stabilize the control system.

Abstract: A system comprising a playback unit and an associated long-playing record on which sound information is recorded in a time division multiplex code on several tracks. Upon reproduction the same track is scanned n times with the aid of a beam of light before this beam of light is directed to the next track. With the aid of a sampling gate the pulses comprising the sound information in time division multiplex code and associated with a first sound channel are sampled with the aid of said sampling gate while during a second revolution pulses from a second sound channel etc. are sampled.In order to operate this sampling gate in synchronism with the scanning of said pulses the playback unit comprises first synchronizing means responding to pulses also comprising the sound information. Furthermore, at the commencement of each track, starting pulses are provided to which second synchronizing means respond.

Abstract: Device for reading-out a disk-shaped record carrier. To compensate for time-base errors of the detected signal caused by eccentricity or out-of-roundness of the record carrier, a tangential tracking system is provided with which the tangential position of the scanning point on the record carrier can be controlled. A control signal for this tangential tracking system is obtained by extracting the line synchronizing signal from the detected video signal. By ensuring through the use of a filter element that the overall transfer function of the control system exhibits a band-pass characteristic about the frequency which corresponds to the speed of the record carrier, a suitable tangential tracking is ensured.

Abstract: A color television system for transmitting a color television signal, specifically for recording on and subsequently reproducing from a record carrier. The color television signal to be transmitted contains a first carrier which is frequency-modulated with the luminance information and a second carrier which is modulated with the chrominance information, whose frequency lies between zero and the first-order lower side band of the modulated first carrier which corresponds to the highest modulation frequency. Said second carrier does not have a fixed frequency, but is locked to the instantaneous frequency of the modulated first carrier by a constant integral ratio. Depending on the characteristics of the transmission medium and the signal processing equipment said ratio is preferably two or three.

Abstract: An arrangement for focussing an image of an information structure which is disposed on or in a substantially flat record carrier, light being projected onto the light-sensitive detector via an optical element and a record carrier, which detector via a control system controls the optical element, the control system also receiving a signal which is a measure of the velocity of movement, which signal limits said velocity of movement.

Abstract: A device for writing information in a disk-shaped record carrier, and/or for reproducing the recorded information, the transducer being radially movable relative to the record carrier, which transducer is disposed on a tubular member, which at its one end is provided with a drive coil and at its other end with a tachometer coil, which coils are movable in an air gap of a stationary magnet system.

Abstract: Circuit arrangement for stabilising the speed of a d.c. motor which is controlled via a control amplifier, and drives a tacho-meter which is connected between the bases of a "long-tailed pair," a tuned circuit being included between the collectors which is tuned to the tacho frequency and which attenuates the other frequencies, the voltage across the tuned circuit being applied to the control amplifier via a charge pump.

Abstract: A record player for disk-shaped video records, provided with an automatic record centering device which includes an adjusting mechanism.The drive means of the adjusting mechanism includes at least two movable transmission elements which act in mutually different directions, each transmission element being movably connected to the frame, engaging with the turntable under pretension and cooperating with a drive means, at least one resilient element being disposed between the drive means and the transmission element.