Abstract: An improved local area network node of the type described in ANSI/IEEE Standard 802.5, including a receiver-demodulator having an input connectable to the ring and having a received data output and a received clock output, an elasticity buffer connected to the received data output, a modulator for modulating the output of the buffer in accordance with a signal at a clocking input of the modulator, and a phase-locked loop interposed between the received clock output of the demodulator and the clocking input of the modulator, the loop including a voltage-controlled oscillator, a phase detector and a filter connected for providing a control-voltage to the oscillator.

Abstract: A photochromic material adapted for coating light transmissive materials. The photochromic material contains photosensitive silver halide crystals having dimensions in the range of approximately 50 Angstroms to 800 Angstroms. The silver halide crystals are surface doped with copper ions and another sensitizer selected from mild reducing agents or sulfur-bearing ions. The crystals are dispersed in a protective polymer that does not irreversibly bind halogen.

Abstract: The invention includes a drain guard and drain protection system. The drain guard includes a cross-sectionally L-shaped frame having a base and an upstanding sidewall extending therefrom. The upstanding sidewall has a plurality of spaced openings. The base may also have a plurality of spaced openings in communication with the plurality of spaced upstanding sidewall openings positioned relative thereto. The frame is of substantially greater perimeter than the perimeter of the enclosed drain opening. The drain protection system includes a surface layer having ballast spread therealong, a drain opening extending through the surface layer, a portion of the surface layer cleared of ballast, the portion outwardly extending from the drain opening to a drain guard of the above-described type.

Abstract: A micro-titre test plate includes a thermoplastic incubation tray having an array of a plurality of wells extending therethrough, a filter, and a thermoplastic harvester tray for supporting the filter sheet. The harvester tray has a plurality of apertures therethrough arranged to be registerable with the bottoms of the wells in the incubation tray. To prevent cross-talk between the wells along the filter, the facing surfaces of the harvester tray and incubation tray are provided with mating ridges and grooves circumscribing the juncture of each well and aperture. In one embodiment, the ridges and grooves are thermally bonded to one another to provide a fluid-impervious barrier trapping respective filter disks in the juncture of each well and aperture. In another embodiment, the harvester tray is formed of a pair of apertured, thermoplastic sheets nested with respective thermally bonded grooves and ridges to trap the filter, the harvester tray being not necessarily bonded to the incubation tray.

Abstract: A portable loudspeaker system that includes loudspeaker means for reproducing relatively high audio frequencies, and amplifier means, and further includes a carrying case formed as a relatively rigid, low-density, releasably matable pair of polystyrene shells that define an enclosed interior space when mated. Mounted in an opening through a wall of one of the shells is a woofer for reproducing only relatively low audio frequencies as acoustic waves radiating away from said case. Disposed within the case is a body of sound absorbing polyurethane foam that has a plurality of relatively large voids for respectively storing the loudspeaker means, the amplifier means and an optional sound source such as a compact disc player.

Abstract: Disclosed is a data compressing modem for connection to a decompressing modem over communication lines. The compressing modem receives an input data stream, and each character in the data stream is recodified with a compressed character code, the length of which is dependent on the frequency of the character in the data stream. A frequency table is maintained so that changes in the relative frequency of characters in the data stream will be recognized by the compressing modem and the compressed character codes representing such characters will be exchanged accordingly. A decompressing modem, which is connected over communication lines to the compressing modem, processes the compressed character code in a reverse order from the manner in which the compresing modem processing the codes. The decompressing modem also maintains a relative frequency table and as the relative frequencies of the various characters change, the actual characters represented by the compression codes must also change.

Abstract: A powder constant-volume feeder includes a canister having on the inner surface thereof a fin for transferring powder upwards and is inclined to form a return portion for the powder which has been transferred by the fin. A bucket wheel has a plurality of buckets for continuously transferring the powder from the interior of the return portion to a powder hopper. The powder hopper receives the powder from the interior of the buckets of the bucket wheel. A constant volume of powder can thus be fed continously at a constant bulk density.

Abstract: Frequency stabilization is disclosed for a laser device, wherein the laser tube is provided with end mirrors which are mounted in extensions at the respective ends of the laser tube. The laser tube extensions have reduced sections which are movable to allow adjustment of the end mirrors in the laser device. The reduced sections are preferably made of metallic material. The means to stabilize frequency provided is the application of heat or current or both to and around a reduced metallic section in the laser tube extension. This may be accomplished by the passing of current through a wire wrapped around the reduced metallic section. The passing of such current causes the reduced metallic section to contract and expand along an axis in line with the laser tube, and as well as a magnetic field is induced upon the gaseous medium within the laser tube. By such means controlled by suitable circuitry, laser frequency stabilization is accomplished.

Abstract: The present invention is a multidose capsule including a tube having a first end and a second end and a dividing wall, supported by the tube, which separates the tube into first and second chambers. First and second removably supportable caps are slidable along each tube end to the extent sufficient to securely seal the chamber thereunder. In alternative embodiments both the dividing wall and the capsule periphery with respect thereto are frangible such that the capsule may be broken in two under an applied stress.

Abstract: The present invention is a method of producing single, unaggregated magnetic iron oxide particles. An iron or iron and divalent metal halide feed solution is kinetically atomized into a high velocity flame. The feed solution is vaporized and held in a reactor at a temperature and partial pressure of an oxidizing phase sufficient to form either ferrous oxide or magnetite particles. The iron or iron and divalent metal halide vapor reacts with the oxidizing phase vapor and converts to either ferrous oxide vapor or magnetite vapor. Since the vapor phase is beyond equilibrium concentration ferrous oxide or magnetite particles precipitate from the vapor phase. Quenching of the magnetite particles at an enhanced rate to less than 500.degree. C. in a reducing atmosphere renders magnetite and in a oxidizing atmosphere renders maghemite. Quenching of the ferrous oxide particles in a non-oxidizing atmosphere produces magnetite particles.

Abstract: A method for producing fine magnetic particles having the barium or strotium ferrite M-phase crystal structure. An iron and alkaline earth metal halide feed solution is vaporized to form a precursor and oxidizing vapor phase. The precursor and hydrolyzing or oxidizing vapor phases are held in a reactor at a temperature sufficient to effect vaporization of the feed solution yet which is below the melting point of the desired M-phase crystal structure. Small iron oxide particles precipitate from the vapor phase and alkaline earth oxides thereafter. The alkaline earth oxide particles diffuse into the iron oxide particles to form the desired M-phase structure. When the desired width and thickness of the M-phase crystal platelets is achieved, the M-phase particles are cooled by quenching.

Abstract: Disclosed is a data compressing modem for connection to a decompressing modem over communication lines. The compressing modem receives an input data stream, and each character in the data stream is recodified with a compressed character code, the length of which is dependent on the frequency of the character in the data stream. A frequency table is maintained so that changes in the relative frequency of characters in the data stream will be recognized by the compressing modem and the compressed character codes representing such characters will be exchanged accordingly. A decompressing modem, which is connected over communication lines to the compressing modem, processes the compressed character code in a reverse order from the manner in which the compressing modem processing the codes. The decompressing modem also maintains a relative frequency table and as the relative frequencies of the various characters change, the actual characters represented by the compression codes must also change.