Abstract: Sample introduction for atomic absorption spectrophotometry is effected by passage through a heated, axially displaceable capillary tube of a thermospray device; at least a fraction thereof is vaporized so that it emerges from one end of the capillary tube as a jet. A carrier liquid is forced through the capillary tube by a high pressure pump. In a retracted position, the outlet end of the capillary tube is disposed in a vacuum exhaust chamber. The sample is contained in a sample loop adapted to be connected into the flow path of the carrier liquid through an inlet valve. The capillary tube then advaces so that said end is projected into a furnace pre-heated to drying temperature. The sample is thus deposited on the inner wall of the furnace whereas the vaporized carrier is drawn off. The furnace is then heated to atomization temperature and subsequently cooled to the drying temperature.

Abstract: The invention is directed to cooled mirror assemblies which include, in combination, a first heat exchanger plate having an upper surface forming a mirror facesheet and a plurality of cooling channels thereunder, a second distribution plate disposed underneath the first plate, which has an upper foam layer, hydraulic apparatus for feeding coolant fluid to the cooling channels and to the foam layer, and hydraulic apparatus for bleeding the coolant from the cooling channels and from the foam layer. According to one aspect of the invention the hydraulic apparatus for bleeding the coolant fluid is disposed closely adjacent the hydraulic apparatus for feeding the coolant fluid to counteract the effect of the temperature rise of the cooling fluid on the distortion of the mirror assembly.

Abstract: A method and apparatus for standardizing spectral line intensities in a spectral monochromator separate an input beam into a sample spectral line characteristic of a sample element, a reference spectral line, a standard spectral line and a background spectral band. At a first point in time an intensity I.sub.A of the sample line, a first intensity I.sub.R1 of the reference line and a first intensity I.sub.B1 of the background band are measured. At a second point in time an intensity I.sub.S of the standard line, a second intensity I.sub.R2 of the reference line and a second intensity I.sub.B2 of the background band are measured. An intensity ratio IR defined by the formula ##EQU1## is computed wherein the intensity ratio IR represents a standardized intensity of the sample line compensated for source fluctuations.

Abstract: A detector cell assembly for use in a spectrophotometer comprises a thermally insulating body having a bore with open ends therethrough and transparent windows closing the ends of the bore. An inlet passage and an outlet passage open into the bore adjacent the opposite ends thereof for flowing fluid therethrough. The body has size defined by an outer surface spaced laterally from the bore by a distance of at least about two times the bore diameter. Preferably the thermally insulating body is polymeric and has an outwardly facing annular surface respectively encircling each end of the bore approximately normal thereto and in contact with a corresponding surface on the respective window. A spring urges each respective transparent window against the respective annular surface to effect a fluid seal between the body and each window.

Abstract: A reference and calibration grid (44a or 44b) of silicon is incorporated into a particle beam lithography system (10) and used to calibrate the system (10). The grid (44a or 44b) is formed in a silicon die (50) of much thicker structure and with square holes (64) and with a period to enable direct coordination with binary electronics. The grid (44a or 44b) is coated with a suitable material, preferably gold (72), to prevent charged particles or electrons from passing through the solid portions of the grid and the grid is preferably mounted on a grid holder (52) which can be aligned to the X-Y reference on the workpiece stage (32) and may be adjusted in tilt and in height (Z direction). The crystallography of silicon provides accuracies in orthogonality, corner radii, and edge roughness required for grids used as fiducials for particle beam lithography.

Abstract: A three-axis adjustment detector mounting assembly in a spectrometer comprising first and second interconnected support plates with a pivot ball assembly interconnecting the first plate to the spectrometer for pivotal positioning of the first plate about first and second axes and a plurality of pivot ball assemblies interconnecting the first and second plate for pivotal positioning of the second plate about a third axis with a detector element mounted to the second plate such that a first adjustment screw mounted to the first plate moves the detector along a horizontal x-axis, a second adjustment screw mounted to the first plate moves the detector orthogonally along a z-axis, and a third adjustment screw mounted to the second plate moves the detector vertically along a y-axis for three-axis detector alignment.

Abstract: A direct-imaging, monochromatic electron microscope includes an objective lens for collecting a substantial portion of emitted electrons from an area across a sample surface, and focusing the electrons through an image plane. A collimating lens for collimating the electrons into beams is located at its focal distance from the image plane. An energy filter with an entrance aperture is receptive of the beams to transit monochromatic beams, and a transfer lens is receptive of the monochromatic beams for refocusing the same through a projection lens to effect an image of the plurality of spots in a projection plane. The objective lens is formed of a magnetic toroidal coil having a central hole therein with a dish-shaped magnetically permeable member cupped coaxially over the toroidal coil. The permeable member has a neck portion protruding through the central hole. The sample surface is interposed proximate the objective lens between the objective lens and the energy filter.

Abstract: The invention is directed to a scanning Michelson type interferometer assembly which includes a beam splitter assembly for receiving a beam of radiation from a source, a stationary plane mirror for receiving and returning a first subbeam over a fixed optical path from the beam splitter assembly and an adjustable plane mirror for receiving and returning a second subbeam over a variable length optical path from the beam splitter, a system for receiving the combined output beam from the beam splitter assembly for forming a spectrum of the input beam radiation, a path difference generator having a pair of parallel spaced mirrors mounted so that the second subbeam is incident on one mirror and is reflected by both mirrors so as to emerage from this direction of incidence, the beam splitter assembly and the stationary plane mirror and the adjustable plane mirror as well as the optical path difference generator assembly being all mounted on a single, rigid monolithic structural frame to provide stability for the ent

Abstract: A variable width transparent photographic film vacuum hold-down device. Two spaced parallel vacuum slits formed on a flat platen are connected by the longitudinal edges of the film, and when covered by a flexible cover sheet form two vacuum channels holding the film flat and unobscured to the extreme edges. Any film width not exceeding the length of the vacuum slits is held without any modification or adjustment to the device. Any length of film can be used.

Abstract: Liquid chromatography column coupling assembly having a column enclosed in a housing member to form a column cartridge and including coupling assemblies at respective ends of the cartridge, each comprising a coupler member and a collar member. The coupler member and collar member are tubular in configuration and disposed in coaxial telescoping relation with one end of the coupler member abutting the respective end of the column with an annular seal interposed therebetween. The collar member has one end threaded onto the end of the column housing and at its opposite end an inwardly extending radial flange coacting with an outwardly extending radial flange on said one end of the coupling member. Rotation of the collar member when threading it onto the column housing causes relative axial displacement of the members to compress the seal between the abutting ends of the column and coupler member.

Abstract: The automatic serial testing of the heats of transformation of material samples is accomplished. The samples are enclosed in capsules which are placed into sample carriers on a turntable. A transfer mechanism transfers the capsules from the turntable to a controllably heatable test sample receiver and, after the measurement, back to the turntable. The entire arrangement is located in a housing filled with nitrogen. The sample carriers with the capsules can be inserted into this housing and onto the turntable through an air lock.

Abstract: It has been discovered that a glass envelope at elevated temperature containing a noble gas will result in electrons being evolved. The phenomenon has been employed to construct both argon and helium detectors for gas chromatography.

Abstract: A cobalt bonded tungsten carbide powder is produced by a method comprising preparing a mixture consisting of a first tungsten carbide powder having a particle size of -5 microns, a second tungsten carbide powder having a particle size of -44+10 microns, a cobalt powder having a particle size of -5 microns and a carbon powder having a particle size of -1 micron. The mixture has proportions, by weight totaling 100%, of about 10% to 30% first tungsten carbide, 40% to 80% second tungsten carbide, 8% to 25% cobalt and 0.5 to 3% carbon. The mixture is processed by compacting, sintering, crushing, and classifying to produce the cobalt bonded tungsten powder in a size range -100+10 microns.

Abstract: A desiccant system is for maintaining an enclosure at atmospheric pressure and in a gas controlled condition. The system includes desiccant material contained in two gas permeable packets each having a flattened side. A perforated box has a cover plate and is adapted for retaining the two packets with the respective flattened sides juxtaposed. An open tube has a length to internal diameter ratio of at least about ten and an outer end open to atmosphere through the cover plate. An inner end of the tube is positioned centrally between the flattened sides of the packets. The box is insertable into a port in an enclosure with the cover plate adapted to seal the port.

Abstract: Disclosed is a chromatographic column having an elongated housing, an elongated central core element, a plurality of annular, concentric would fiber layers, so as to form a plurality of uniform fluid passageway, though the housing, and a coating of stationary phase material on the passageways.

Abstract: A mounting system includes a carriage member section of an apparatus being isolated from external vibrations, and a bench member having three support assemblies thereon to support the apparatus. Each support assembly comprises an upwardly oriented pin affixed to the bench member, and an elastomer isolating ring with a central hole press fitted onto the pin. The carriage member has an aperture therein aligned with each support assembly. The aperture is shaped as a slot portion superimposed centrally on a circular hole portion press fitted over the isolating ring. The isolating ring thereby is retained in compression between the pin and the outer wall such that elastomer overfill of the isolating ring can expand into the slot portion sufficiently to compensate for tolerance misalignment between the support member and the aperture, without substantial thickening of the isolating ring. A clamping assembly with an elastomer isolation pad holds the carriage onto three upward protrusions over each support assembly.

Abstract: The system includes a synchronous voltage-to-frequency converter connected to receive an analog input signal voltage and to generate a train of output pulses. A counter is connected to receive and count the output pulses and a digital register is connected to the counter for periodically receiving and storing the count in the counter. A conversion interval timer circuit is connected to control the operation of the counter and the register to determine a conversion interval during which the output pulses from the synchronous voltage-to-frequency converter are accumulated in the counter and then stored in the register. The conversion interval timer circuit is operable to determine the end of a prior conversion interval and the beginning of a new conversion interval in response to a predetermined phase of a predetermined cycle of the ac power line voltage.

Abstract: A method of and apparatus for producing a dense and tenacious coating with a thermal spray gun including a nozzle member and a gas cap. The gas cap extends from the nozzle and has an inwardly facing cylindrical wall defining a combustion chamber with an open end and an opposite end bounded by the nozzle. An annular flow of a combustible mixture is injected at a pressure of at least two bar above atmospheric pressure from the nozzle coaxially into the combustion chamber. An annular outer flow of pressurized air is injected from the nozzle adjacent to the cylindrical wall. Heat fusible powder entrained in a carrier gas is fed axially from the nozzle into the combustion chamber. An annular inner flow of pressurized air is injected from the nozzle into the combustion chamber coaxially between the combustible mixture and the powder-carrier gas. Upon combusting the annular mixture a supersonic spray stream containing the powder is propelled through the open end to produce a coating.

Abstract: A powder feeding system includes closed loop regulation of powder feed rate. A feed gas is discharged under constant pressure into an enclosed hopper. A valve is disposed to constrict a carrier conduit conveying powder in a carrier gas. A load cell measures the rate at which powder is flowing from the hopper through an intake orifice into the carrier conduit, and filtered flow rate signal is produced. A first controller produces a reference signal representative of the difference between a set point signal and the flow rate signal. A differential signal is produced corresponding to the pressure difference between the hopper pressure and a carrier conduit pressure taken between the intake orifice and the valve. A second controller produces a control signal representative of the difference between the differential signal and the reference signal. The valve is responsive to the control signal to proportionately constrict the carrier gas stream such as to regulate the powder flow rate.

Abstract: Apparatus for detecting and determining the direction of arrival of optical radiation. The apparatus includes a first mask having one or more slit apertures, a binary encoding mask which combines the functions of angle sensing and digitizing using a so-called gray encoding scheme, and interdigitated detector(s) to produce differential electrical signals, and output processing electronics for providing a digital code or word corresponding to the angle-of-arrival of the incident radiation.