Abstract: The present invention provides a bias generation circuit in which the voltage of electrically isolated circuits are stabilized by providing a photovoltaic diode in each circuit, a common light source uniformly positioned to provide equivalent energy to each photovoltaic diode and an operational amplifier, configured with a capacitor as an integration circuit, driving the common light source, wherein one isolated circuit provides feedback to the amplifier, such that variations in the voltage in the isolated circuit causes the amplifier to provide an adjusted signal to the common light source, adjusting the energy output to compensate for voltage variations simultaneously, yet independently occurring in each isolated photovoltaic diode circuit. Such bias voltage circuit may be used with chromatographic ionization detectors as well other devices.

Abstract: A pulsed discharge detector includes a device and method for modular measurement of ionization signals from a sample. The pulsed discharge detector includes a discharge source in a chamber, a collector spaced from the discharge source, a monitor connected to a discharge electrode, an electrometer connected to the collector, a calibrator and a sample and hold processor. The discharge electrodes include a source electrode centrally located in relation to the discharge chamber wall. The collector is centrally located in relation to the chamber wall. Discharge signals are monitored for time and intensity. Collected signals are adjusted based on the discharge intensity. Collected signals are collected during a time window based on the discharge occurrence time. Detector output is predicated on collected signals coordinated with pulsed discharges. The calibrator of the present invention adjusts the collected signals to reduce discharge noise.

Abstract: A pulsed discharge detector includes a device and method for modular measurement of ionization signals from a sample. The pulsed discharge detector includes a discharge source in a chamber, a collector spaced from the discharge source, a monitor connected to a discharge electrode, an electrometer connected to the collector, a calibrator and a sample and hold processor. The discharge electrodes include a source electrode centrally located in relation to the discharge chamber wall. The collector is centrally located in relation to the chamber wall. Discharge signals are monitored for time and intensity. Collected signals are adjusted based on the discharge intensity. Collected signals are collected during a time window based on the discharge occurrence time. Detector output is predicated on collected signals coordinated with pulsed discharges. The calibrator of the present invention adjusts the collected signals to reduce discharge noise.

Abstract: A tapered conic ferrule in accordance with an industry standard is abutted against a male nut. The nut is provided with a length wise passage having an end at a head on the nut. The passage has a radius of curvature to enable the tube to bend, but not sharply so that the tube is not damaged.

Abstract: A variable load mechanism for use in a valve seals the flow of a switched fluid. The flow passes through the mechanism in a region which includes shear seal surfaces. The lives of the components of the valve are extended by limiting the range of excursion in response to valve seat forces. The valve element is provided with a first force from a stack of Bellville washers, for example. A second force acts on the valve element through the spring and is determined by fluid pressure.

Abstract: A method and apparatus are set forth which enables a gas chromatographic column output to be connected with a pulse discharge chamber in which chemically bound chlorine in volatile organic or inorganic samples is measured. A spark discharge is formed in the chamber to ionize and excite helium molecules to a metastable state. In turn, that transfers excitation to a trace of krypton gas in the chamber which is ionized, and the ionized krypton then preferentially binds with chemically bound chlorine. The latter binding occurs with the liberation of a photon centered at about 222 nanometers thereby defining a spectral region of interest which is measured by a photomultiplier tube to quantify chemically bound chlorine.

Abstract: A detection system measures very small concentrations of compounds of interest within gaseous samples. A spark discharge system induces pulsed spark discharges across a pair of electrodes within an inert gas in a gas flow chamber. Various reactions are induced by spark interaction with the flow of inert gas, and with any sample or dopant commingled with the inert gas, in the region of the pulsed spark discharge. This induces photon ionization which creates an instantaneous current flow within the gas flow chamber. Current flow is held constant for all concentrations of sample introduced into the gas flow by means of a control feedback system. The output of the control feedback system is indicative of sample concentration. The system responds linearly over approximately five orders of magnitude of sample concentration for use with the sample which will be described and low femtogram sensitivity is achieved.

Abstract: A valveless positive displacement pump with a closed end cylinder has fluid inlet and outlet ports adjacent to the closed end. A piston is reciprocally and rotatively driven in the cylinder. The piston is provided with crisscrossed helical slots formed thereon which communicate specifically with the inlet and outlet ports for pumping fluid through the positive displacement pump. The piston is rotated by a drive shaft connected to a motor and reciprocated by an cam actuator mechanism cooperating with the drive shaft.

Abstract: A pulsed discharge photoinoization detector is set forth which comprises a plurality of closed chambers for receiving different types of carrier gas flowing there through between inlets and outlets. The carrier gases are exposed to a pair of electrodes forming a spark across each chamber and through each carrier gas. At least one component of each type of carrier gas is excited within each chamber by the spark discharges, and the resonance energies of each type of carrier gas are different. The sample to be analyzed is split and a portion is injected into each of the closed chambers where it is exposed to the excited carrier gases. Carrier gases, upon decay, serve as sources of ionizing radiation of differing energy which react with compounds within the sample gas producing ionization currents which are a function of the types of sample gas compounds and the types of carrier gases.

Abstract: A pulsed rare gas photoionization detector apparatus is set forth and incorporates a closed chamber for receiving a carrier gas flowing there through between inlets and outlets, and the carrier gas is exposed to a pair of electrodes forming a spark across the chamber and through the carrier gas. One component of the carrier gas is a dopant which selected from a plurality of rare gases. The sample to be analyzed is injected into the closed chamber where it commingles with the carrier gas. One reaction involves the formation of selected dopant in an excited state, which upon decay, serves as a source of ionizing radiation which reacts with sample compounds producing detectable events. These events are used to identify and quantify unknown compounds contained in the sample. The methods and apparatus are especially useful in selectively ionizing the compounds to be measured while not ionizing other constituents of the sample. This greatly enhances the signal-to-noise ratio for detecting impurity compounds.

Abstract: A circular chamber is disclosed. Helium is introduced into the chamber to swirl in a circle to flow past a pair of spaced electrodes forming a spark in the helium. The chamber enables a sample detected by interaction with spark initiated ionization.

Abstract: An isolated detector for gas is set forth and incorporates a closed source chamber in cooperation with a sample chamber through which sample gas flows. Gas within the source chamber comprises Krypton which is excited to a metastable state by a pulsed, high voltage, direct current spark. Subsequent decay of metastable argon emits ionizing radiation which passes through a membrane window into the sample chamber thereby ionizing selected constituents within the sample gas. Charged particles resulting from the ionization of selected constituents are collected with voltage biased electrodes in the sample chamber, and the magnitude of the resulting current flow is related to the concentration of the ionized molecules or compounds. The apparatus for generating ionizing radiation requires no external source of gas, is rugged, is relatively inexpensive to manufacture and operate, and exhibits an operating life much longer than source lamps used in prior art devices.

Abstract: A pulsed discharge helium ionization detector set forth and comprises an elongate cylindrical body having an axially flow path. A helium source is connected to deliver helium flowing along this path. At some location in the helium flow path, transversely positioned, facing electrodes are located. When provided with pulses discharged across the helium flow path wherein the discharge is either monopolar or bipolar pulses, the spark interacts with the helium to create photon ionization. Downstream within view of the spark, a counter flow sample injection tube is positioned to deliver samples at a reduced flow rate. The sample is swept back along the helium flow path past a pair of electrode rings spaced along the flow path. The interaction of the photon ionization with the sample creates a current which can be detected by an electrometer across the two terminals.

Abstract: A spark detection apparatus is set forth and incorporates a closed chamber for receiving a carrier gas flowing therethrough between inlets and outlets, and the carrier gas is exposed to a pair of electrodes forming a spark across the chamber and through the carrier gas. One component of the carrier gas is argon. The sample to be analyzed is injected into the carrier gas. One reaction involves the formation of metastable argon which upon decay serves as a source of ionizing radiation which reacts with sample compounds producing detectable events. These events are used to identify and quantify unknown compounds contained in the sample. The methods and apparatus are especially useful in measuring pollutant compounds in atmospheric samples since the ionizing radiation emitted from the decay of metastable argon is below the ionization potential of the major constituents of air. This greatly enhances the signal-to-noise ratio for detecting impurity compounds when the detection system is used to monitor air quality.

Abstract: A sample is loaded along with a carrier gas into a column. The column discharge is introduced into a chamber downstream of spaced electrodes which create a pulsed DC spark. The spark produces a spectral emission and a metastable carrier gas dispersion that then reacts with molecules of the sample to bring the sample to an excited state. The excess energy surrendered by the sample is characteristic of the species and can be measured by detector electrodes in the chamber.

Abstract: A spark detection apparatus is set forth and incorporates a closed chamber for receiving a carrier gas flowing therethrough between inlets and outlets, and the carrier gas is exposed to a pair of electrodes forming a spark across the chamber and through the carrier gas. Compounds of interest interact with the spark. The spark forms a diffusion of electrons or alternately ions during the spark distributed thereafter. The chamber includes a detector electrode spaced from the spark. High mobility particles (primarily electrons) are observed almost instantaneously with the spark while low mobility ionic particles diffuse more slowly after the termination of the spark. Using an inert carrier gas, high energy metastable molecules are dispersed and give up energy over time after the spark. The output is obtained from the electrode during, immediately after, or after a long delay relative to the spark. Another alternate output is obtained from the observed spectra during the spark and after the spark.

Abstract: The present apparatus in the preferred and illustrated embodiment comprises first and second rings which are respectively affixed to the mouthpiece and mouth pipe. As force is increased by the musician in holding the mouthpiece against his lips, such force is measured by cooperative measuring means fixed to said first and second means. In the preferred embodiment, the force measuring means includes an aligned pin on one of said means positioned relative to a transducer coil to thereby provide an indication of force. The signal indicative of force is delivered to a time based recorder and is recorded as a function of time along with additional data including sound intensity levels and frequency of the music to provide correlation between force, intensity and frequency as a function of time. A method is also taught including the recording of such data to teach the musician to reduce the force applied against his lips.

Abstract: This disclosure sets forth a variable tensioning system for use in a valve featuring shear seals. In the preferred and illustrated embodiment, a spring system provides loading on the valve element to force that element into engagement with a valve seat. A sliding sealing surface is accomplished in this contact. The valve element may be a tapered plug, a sphere or a flat face or plate. Typically, it is a hard member working against a seat supporting a seal surface featuring a sliding shear seal. A specific minimum load is applied to the valve element to accomplish sealing against minimum pressure. The present apparatus incorporates a closed chamber enclosing a slideable piston. The piston has a specific cross-sectional area exposed to fluid pressure of the fluid being controlled by the valve. The piston applies pressure dependent force against the valve element.

Abstract: The illustrated and preferred embodiment of the present invention is a sample delivery system for packed or open tubular column gas chromatographic apparatus. The apparatus comprises a sample injection valve constructed and arranged to utilize multiple ports wherein a gaseous or liquid sample is injected through a syringe into an injection port, the valve being heated to volatilize the sample which is then temporarily stored in a sample storage loop. The valve apparatus rotates to connect the sample storage loop with an inlet conduit delivering the sample and sweep gas to an exponential dilution flask (EDF). The flask provides an output which delivers a diluted portion of sample with the extent of dilution controlled as a function of time through a second valve assembly. The second valve assembly is switched with a timer to deliver a portion of the sample flow and sweep gas to a capillary bore gas chromatographic apparatus.

Abstract: An adaptor assembly for connecting a tubing with either a male or female fitting is disclosed. Flow control means within the adaptor assembly comprise an important feature of the disclosed and preferred embodiment wherein the flow control means comprises a filter. The filter is a disk of filtrant material such as a nonwoven fiber formed into a pad of specified thickness and cut in a circle. It is placed adjacent to a shoulder in the adaptor and is supported by a surrounding ring.An alternate embodiment which is one of the preferred embodiments hereof includes a check valve serving as the flow control means. The check valve is constructed with a circular valve seat having a chamfered shoulder, a spherical valve element which closes against the seat to block flow, a surrounding sleeve which permits the check valve element to move toward and away from the chamfered seat and a transversely extending disk to block the passage. The disk blocks the valve element from escape.