Abstract: An automatic sample injector for high pressure liquid chromatography, utilizing a cassette-like holder of a plurality of sample columns and an automatic injection unit which sequentially and successively advances the cassette and removes each sample therefrom in accordance with the test to be conducted on the sample. The cassette-like sample carrier utilizes a plurality of sample columns disposed in line with each other, with the body of the cassette being unsymmetrical to prevent reversal thereof in the injection machine. The injection machine, when a sample cassette is placed thereon, automatically advances the cassette to the first sample column, connects the column to the chromatographic or other system, removes the sample therefrom, decouples the sample tube from the system and again advances the cassette to the next sample tube therein for similar processing thereof.

Abstract: A small volume electron capture detector has a cylindrical cell 120 inside which there is provided a generally funnel-shaped insert structure 130 having a cup-shaped section and a cylindrical section. The rims of the cup-shaped section nearly touch the inner walls of the cell 120 so as to separate the active volume from the areas at the top corners of the cell 120 which are not actively swept by the carrier gas, thus reducing the tailing of chromatographic peaks.

Abstract: A method and apparatus for use in gas chromatography for confirming the presence of compounds in the sample. By directly comparing the transient decay time domain signals of the sample and of known compounds as detected in an ion cyclotron resonance mass spectrometer connected to the chromatographic column, one is able to effect sample confirmation without the computer intensive processes of Fourier transformation and analysis of the resulting mass spectrum.

Abstract: Disclosed are a method and apparatus for rapidly heating a thermionic vacuum tube cathode, thereby enabling the vacuum tube to be placed in useful operation shortly after the tube is switched on. Rapid heating of the cathode is achieved by passing current through the cathode, thereby directly heating it. Simultaneously, the cathode is also heated by an indirect radiant heater and by electron bombardment by electrons emitted from the heater. When the cathode reaches its operating temperature, the direct heating current and the electron bombardment are stopped and the cathode is maintained at its operating temperature by the indirect heater alone. Cathode warm-up times of less than 1 second may be attained using this invention.

Abstract: A sample valve for solute modulated synchronous detection alternately directs into a detector a sample gas stream F.sub.1 which passes through a modulator cell and a reference gas stream F.sub.2 which passes through a balance cell. The sample valve is made of a symmetrically structured chamber with inlets and outlets. An ordinary valve causes a control gas to stream into the chamber alternately though one of two openings to exit openings of the chamber are synchronously opened and closed so that gas streams F.sub.1 and F.sub.2 are alternately led into the detector and out of the system.

Abstract: An electron capture detector for use with a capillary column is provided with a sample inlet comprising a tubular anode through which sample molecules and a make-up gas are introduced into the detector cell. The tubular anode has side ports for producing a plug-like flow inside the cell. The inner surface of the anode is protected by an insulating tube so that the capillary column can be extended to a point beyond the side ports without the fear of its electrical contact with the anode. This allows the sample molecules to flow nearly entirely in the center section of the cell. The peripheral regions of the cell where a radioactive foil is disposed is swept nearly entirely by the make-up gas entering the cell through the side ports. This has the effects of reducing sample dilution by the make-up gas and sample loss due to contact with the detector walls.

Abstract: A sample modulator cell for chromatographic analysis uses a diverting valve to send a carrier gas into a duct in a generally closed circular form periodically alternately through two separate ports. A sample inlet port opens between the carrier ports so that a sample-containing gas periodically alternately flows to an exit port through two channels A and B of different lengths in the duct. A phase-shift of 180.degree. is introduced between the channels so that all of the sample introduced into the modulator will be used for the analysis, thus increasing the peak response.

Abstract: A baffle divides a housing into first and second compartments. The first compartment includes a chromatography oven having a fan for circulating heated air over the columns while the oven is closed and for sucking ambient temperature cooling air in the first compartment into the oven while the oven is open. Ambient air is sucked into a tortuous path in the first compartment. Cooling air from the second compartment flows into the first compartment via openings in the baffle. The cooling air flows over the oven exterior and is at least partially sucked into the oven by an oven fan while the oven is open. The oven heater, coaxial with the blades, is located between an oven wall and blades. A ring baffle, having approximately the same diameter as and coaxial with the blades, is located between the wall and the blades. A fan outside of the oven sucks air from the oven through an outlet while the oven is open.

Abstract: A liquid sample in a syringe can be injected into a capillary column with inner diameter less than 200 microns without inserting the injection needle of the syringe into the column. The end of a modified injection needle according to this invention has a tubular opening with inner diameter sufficiently large so that the intake end of the column can be inserted inside, thereby establishing an annular duct between the needle and the column. A carrier gas is caused to flow through this duct while the plunger on the syringe is pressed to squeeze the liquid into the needle, thus forcing the liquid into the capillary column.

Abstract: An optimized annular sputter target assembly for use in sputtering magnetic material, comprising a thin target piece of magnetic material mounted on a backing structure of nonmagnetic material. Said backing structure provides means for easy mounting and removal of the target assembly and for providing good thermal and electrical contact with the cooling wall of the sputter source. The target piece has a portion extending radially outwardly from said cooling wall thereby providing greater target surface area.

Abstract: A hydraulic pulse dampener has two diaphragms, each positioned opposite a recess formed in the housing. The regions between the diaphragms and the associated recesses are sealed from the fluid which flows through the dampener so that a rise in pressure in the fluid may cause each diaphragm to flex towards the recess behind until it may completely nest in it. The diaphragms are designed differently so that they will begin to flex and take a completely nested position in different pressure ranges.

Abstract: The contrast ratio of an image intensifier of the photocathode-amplifier-phosphor type is increased by using a fiber optic plate of which the thickness is reduced to such extent that the plate may not be able to function as a vacuum seal or an electrical insulator when a typical voltage for the operation of the intensifier is applied to the phosphor layer. This relatively thin fiber optic plate is placed entirely inside a vacuum, protected from the atmospheric pressure by a thick output window plate which is optically transparent.

Abstract: A hydraulic pulse dampener of liquid compressibility type has a flexible tubing wound around a form within a liquid-tight housing filled with a compressibility liquid and a stiff diaphragm placed adjacent a recess formed in a receiving member. As the fluid flowing inside the tubing experiences pressure pulses, the walls of the tubing expand and transmit the pulse energy through the compressibility liquid and causes the diaphragm to gradually flex towards the recess until it may completely nest in it. The recess in the receiving member preferably has a central flat portion so that the flexing diaphragm will first contact the receiving member at the center and the nesting will spread outwardly therefrom.