Abstract: There is disclosed apparatus for monitoring the concentration levels of halogen gas in a gaseous atmosphere as confined in an enclosure over a relatively extended period of time. Such monitoring apparatus includes a sensor including first and second electrodes disposed to define a space therebetween through which the gaseous atmosphere flows and a voltage source for applying a voltage between the first and second electrodes whereby an ionization current flows to the first electrode. A control mechanism illustratively in the form of a programmed microcontroller monitors the ionization current collected by the first electrode as the output signal of the sensor, to determine an increase therein as would be indicative of a halogen leak. Upon determining an increase of the sensor output signal above a predetermined difference, the control mechanism removes the energization from the halogen sensor whereby the ionization current is terminated and the life of the sensor extended.

Abstract: A cold cathode gauge including a glow lamp or the like disposed within the vacuum space of the gauge for initiating the gauge discharge, the lamp emitting UV or blue light directly at at least the cathode of the gauge where the energy of the light is sufficient to release photoelectrons from the cathode to thus initiate the discharge. A member is also provided for removably positioning the glow lamp within the vacuum space whereby the lamp can be removed during bake out and then subsequent thereto, be inserted within the vacuum space to thus enhance longevity of the lamp.

Abstract: A method of determining the percentage gas content of an insulating glass window unit or the like comprises the steps of applying a voltage to opposed panes of the unit, progressively increasing the voltage, monitoring the voltage and recording the magnitude of the voltage at which a continuous discharge occurs, or is about to occur, between the electrodes and converting the magnitude to a number indicative of the percentage gas content of the gas between the panes.

Abstract: An ignition plug for an internal combustion engine includes an ionization current detector electrode 20 adapted to be coupled to an external ionization detector circuit. Preferably, the ionization current detector electrode extends through a lateral through-hole formed vertically through an expanded portion of the electrical insulator 3. The lower end of the ionization current detector electrode may extend into the combustion chamber by a predetermined length. Further, the lower end of the ionization current detector electrode exposed to the fuel/air mixture within the combustion chamber may form a cylindrical grid to increase the contact area with the combustion gas.

Abstract: A cold cathode gauge including a glow lamp or the like disposed within the vacuum space of the gauge for initiating the gauge discharge, the lamp emitting UV or blue light directly at least at the cathode of the gauge where the energy of the light is sufficient to release photoelectrons from the cathode to thus initiate the discharge. Various techniques for supplying power to the lamp are also disclosed.

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: Apparatus for measuring the concentration of carbon compounds in water, the apparatus including a reaction zone for converting such carbon compounds to free and/or combined carbonaceous acids, a device for introducing at least a portion of the water to be analyzed as liquid or vapor into such zone, a device for contacting such acids with weakly basic anion exchange resin and a device for measuring the electrical impedance of at least a portion of such resin.

Abstract: A gas-amplified ionization detector for gas chromatrography which possesses increased sensitivity and a very fast response time. Solutes eluding from a gas chromatographic column are ionized by UV photoionization of matter eluting therefrom. The detector is capable of generating easily measured voltage signals by gas amplification/multiplication of electron products resulting from the UV photoionization of at least a portion of each solute passing through the detector.

Abstract: A method of and an apparatus for analyzing a granular material contained in a sample of a medium such as water produced by an ultra-pure water producing apparatus includes the steps of adding energy to granular materials contained in a sample which is mixed with the medium, wherein the energy is set to be lower than the breakdown threshold of the medium and to be higher than the breakdown threshold of the granular materials, detecting ions which are generated with the breakdown of the granular materials by using a pair of positive and negative electrodes; and analyzing characteristics of the granular materials based on the ions.

Abstract: A dual-column, dual-detector gas detector and analyzer employs both a photo-ionization detector and a flame-ionization detector. In a survey mode, samples of ambient air are driven through both detectors, and the outputs of both detectors are used to determine the presence of one or more gasses. In analysis mode, fixed-volume samples of ambient air are driven through two elution columns having different properties. The output of each elution column is fed to one of the detectors. The arrival times of gas peaks at the two detectors are employed to develop two lists of candidate gasses. The lists are cross-checked for the presence of each candidate on both lists. Candidates identified from their presence on both lists are identified. A further check attempts to identify candidates which are identifiable from their presence on one of the lists, and not on the other. Components identified in this way are added to the final list.

Abstract: The gas detection apparatus for detecting chemical agents in an air stream includes a radioactive source to ionize the air stream and an electrostatic field to increase the efficiency of the apparatus by neutralizing undesired ions, which allows a radioactive source with a lower radiation level to be used than would be required without such neutralization. A diffusion chamber including a baffle device is then used for an ion selection processes. Additional undesired ions are diffused into the walls of the diffusion chamber while the remaining ions, which are the ones sought to be detected, pass from the diffusion chamber into a collection chamber. Detection of the chemical agent ions is achieved when the remaining ions collide with the walls of a collection chamber, transferring their charge to thereby generate a current.

Abstract: A vapor electrical conductivity cell with sensing plates mounted on insulrs exposed to the vapor. Vapor condensation on those insulators cause errors in the conductivity measurements. The improvement of the invention keeps the insulators at a temperature higher than the vapor. The leakage errors are therefore reduced considerably.

Abstract: An ionization current detector for detecting the combustion states of an internal combustion engine is disclosed, which comprises: a high voltage generation circuit means, including a series circuit of a resistor, a diode, a capacitor, and a Zener diode, coupled across the output terminal of the ignition coil and the ground; diodes coupled across the peripheral terminals of the distributor and a negative terminal of the capacitor; and a current detector circuit including a resistor coupled across the positive terminal of the capacitor and the ground and a voltage divider for detecting the amount of the ionization current. An additional Zener diode is coupled in parallel with the capacitor to limit the voltage across the capacitor. The whole detector is incorporated into a single unit mounted to the distributor cap.

Abstract: A flame ionization detector comprises a housing forming a flame chamber for burning a mixture of hydrogen, oxidant and a sample gas. The flame chamber includes: a nozzle in which the sample gas and hydrogen are intimately mixed prior to injection, an igniter for igniting the gas emitted from the nozzle, inlets for hydrogen and oxidant, and an exhaust outlet through which the burnt gases are removed. A collector electrode is electrically insulated from the housing of the flame chamber. The nozzle and flame chamber housing are electrically grounded, and the collector electrode is maintained at a predetermined potential relative to ground. A pre-chamber is disposed adjacent to the flame chamber to provide a substantially constant pressure input of the sample gas to the nozzle.

Abstract: Apparatus for measuring breakdown plasma, comprising an irradiating device for irradiating a sample with a focused light beam and for causing breakdown of a ultrafine particle to be measured in the sample at the focused beam region to change the particle into plasma; a pair of electrodes arranged on opposite sides of the focused region of the beam; and a device for measuring an electrical resistance between the electrodes under a condition where the breakdown plasma is produced between the electrodes and for determining a diameter of the particle according to the measured electrical resistance serves for accurate measurement of the diameter of the ultrafine particle in the sample.

Abstract: A cylinder head gasket is described which also serves as an electrode of an ionization sensor. The gasket (16) has an electrically conductive surface portion (16c) which is electrically insulated from the cylinder head (14) and from the engine block (12) so that it may serve as an electrode of an ionization sensor. The gasket of the preferred embodiment is of five layer sandwich construction comprising two outer layers (16a, 16b) of soft metal capable of deformation under pressure to effect a gas tight seal with the block (12) and the cylinder head (14), a central core (16c) of electrically conductive material to serve as an ionization electrode and two layaers of ceramic material (16e, 16f) insulating the central core (16c) from the two outer layers (16a, 16b).

Abstract: A gas detector system for detecting gases such as CO.sub.2. Sample air is passed through a critically sized sealed sample chamber in a sample cell. Infrared waves are generated in an insulated heater assembly, and radiate through windows of the sealed sample chamber concurrent with the sample air. The strength and magnitude of the infrared waves is attenuated by the level of gas, such as CO.sub.2, present in the sample air passing through the critically sized sealed sample chamber, and is sensed by a thermopile detector, including a filter for a specific frequency of infrared energy. Electronic circuitry processes the thermopile signal and measures other parameters of the gas detector to provide a signal indicative of the percentage of gas concentration in the air. Extensive use of insulation about and around the thermopile detector electronic circuitry and other components of the detector maximize stability and reliability.

Abstract: An alpha particle counter for detecting individual alpha particles with a detection medium which is ambient air. Energetic alpha particles from radioactive decay products or other sources enter the detector volume through a durable wire screen window and ionize the ambient air detection medium. Ions of one polarity are driven to the central collector electrode by an electric field due to a battery imposed potential difference between the outer electrode and the central electrode and housing. One pulse is produced for each alpha particle losing its energy in the detector. The counting efficiency is substantially one hundred percent (100%) and is relatively noise free because the collector electrode is essentially at ground potential. The collector electrode signal is amplified in a field effect transistor (FET) emitter follower circuit, the output of which is fed to an external counter. Rugged construction and minimum maintenance are inherent features of this alpha particle detector.

Abstract: A detector of ambient radon concentrations in real time comprising a housing, at least three conductive elements one of which being grounded, another being biased with respect to the other conductive elements, and at least one other conductive element being connected in series with an amplifier circuit and a counter circuit, respectively. In operation, when an energized alpha particle enters the housing, it ionizes air molecules, thus producing ions which are collected by the conductive element by virtue of the potential between that element and the other elements. The voltage pulse is amplified by the amplifier circuit and then counted.

Abstract: A method for detection of alien matter content in gas, in which the gas and the materials contained in it are ionized in an ionization room (1). The present methods are inaccurate and unreliable. The invention is based on a method, in which the ionized gas is led through chambers (2) containing different electric fields, out of which at least from one of the chambers the field current is measured, from which a signal is obtained, which describes the existence of alien matters in the gas. More parameters are obtained for detection of different materials by measuring favorably the currents passed through several electric field chambers as well as possibly by branching off from the ionization source the flow to different analysis lines of the electric field chambers.

Abstract: A detector system (10) especially suited for detecting a halogen containing component in a gas stream includes a gas chromatograph (12), which is connected by gas line (13) to pyrolysis chamber (14). Sources (16) of additional gas streams are connected by a gas line (18) to the pyrolysis chamber (14). The detector electrodes in the pyrolysis chamber (14) are electrically connected to detector electronics (20) by line (22). A temperature control circuit (24) is electrically connected to heater (26) by line (28). Heater (26) is thermally coupled to the pyrolysis chamber (b 14) at (30). The pyrolysis chamber (14) is thermally coupled to thermocouple (32) at (34). The thermocouple (32) is electrically connected to the temperature control circuit (24) by line (36). The heater (26) is independent of the detector electrodes and maintains a temperature between about 700 degrees and 1000 degrees Centigrade. The detector electrodes are substantially alkali metal free.

Abstract: Apparatus for measuring corona current in high voltage A.C. ionizers uses an electrical sensor adjacently spaced from at least one of the discharge electrodes and coupled to electronic circuitry for separating capacitive current from the corona current. In one mode, the capacitive current component is measured directly by a first sensor adjacently spaced from one discharge electrode whose corona current flow to such electrode is either obstructed or squelched entirely while a second sensor monitors total current. The signals from the two sensors are electrically subtracted when applied to opposing inputs of a differential amplifier to provide an output signal proportional to just corona current. In a second mode, a measure of corona current is again provided by electrically subtracting from a total current signal input to a differential amplifier a signal equal to the capacitive current component.

Abstract: A detector device for a gas chromatograph, for detecting surface ionization wherein ions will be detected which are formed upon contacting amine compounds and ammonia with the surface of metallic oxides having a large work function. The detector enables detection of poisonous amine compounds and ammonia with high sensitivity.

Abstract: The resistivity of particulate matter in a gas stream, such as a combustion gas stream produced in a coal-fired power plant, is measured by collecting a sample of the particulate on the surface of a porous ceramic cylinder, either with or without an applied collection voltage, and then determining the resistance of the sample with a compound measurement electrode having multiple conductors. The reference electrode and the measurement electrode are spirally wound on the ceramic cylinder in an interdigitated manner, so that the two are laterally adjacent down the length of the cylinder. The pressure within the cylinder is controllable, with a pressure below atmospheric being applied to draw the particulate to the suface and ascertain when a sufficient sample for measurement is present, and a pressure above atmospheric being applied to blow away the sample after the measurement is completed, thereby preparing the instrument for the taking of another sample.

Abstract: The surface ionization detector for analyzing gas mixtures comprises a case (1) accommodating a thermoemitter placed at right angles to the direction of movement of a gas mixture and formed with electrically insulated extended ionizing elements, for example, parallel metal wires (9), each of which is connected to its current lead (11) to provide for independent regulation of heating power for each wire (9). The analyzed constituents of the gas mixture, the molecules of which are ionized through surface ionization, are ionized on the surfaces of the metal wires (9), desorbed therefrom and acted upon a potential difference of about several volts between the thermoemitter the ion collector (8) to move towards the ion collector (8) placed after the thermoemitter and made as a perforated element, for example, a metal mesh (13).

Abstract: A small sample of material is introduced into a vacuum to be analyzed, by ionization of atoms or molecular fragments of the sample using an electron or photon beam. The ionized species are trapped in a structure that defines electric fields or a combination of electric and magnetic fields in such a way that their motions are confined to the interior of the trap and that their motions within the trap are characterized by unique and discrete frequencies of oscillation dependent on the mass-to-charge ratio of the individual species. In order to provide for the detection of the frequencies of the motions, additional electrical signals are applied to the trapping structure so as to cause the motions to take place with a considerable degree of coherence. Alternatively, the coherence may be caused by creation of the ions during a very short pulse of the electron or photon beam at a position within the trapping structure but displaced from a positon of equilibrium.

Abstract: A conductivity probe able to withstand high water temperatures and pressures, and intense nuclear radiation is suitable for use within the core of the nuclear reactor. The probe is made with a ceramic insulator, such as sapphire, and a central electrode that is mounted on the insulator. A sleeve that supports the insulator and the central electrode is made from metals having a coefficient of thermal expansion compatible with the coefficient of thermal expansion of the insulator, such as Kovar. The central electrode and sleeve are bonded to the insulator by a brazed compressive seal that protects an internal conductor in the probe from intrusion of the reactor water. A counter electrode made from a corrosion resistant metal, such as Kovar, is attached to the sleeve so that it extends over the central electrode a fixed, spaced distance. A positioning and signal transfer arrangement operatively supports the sleeve and conveys electrical signals to and from the two electrodes.

Abstract: An apparatus for continuously measuring the hydrocarbon concentration in a gas flow includes at least one flame ionization detector with a combustion chamber housing electrodes between which a current flows due to ionization in the area of a burner flame. The combustion chamber of the flame ionization detector is connected to a suction pump in form of a venturi tube for applying an underpressure in the combustion chamber so as to allow especially sample gas but also burner gas and oxidizer to be drawn into the combustion chamber.

Abstract: A discharge ionization detector which comprises with a cylindrical housing wherein is formed a discharge chamber at one end, and wherein is formed an ionization chamber at the other end an aperture connecting the chambers, arc electrodes being located in the discharge chamber, and emitter/collector electrodes being located in the ionization chamber, the latter comprising flat parallel plates, the housing being provided with an inlet into the discharge chamber for delivering discharge gas to the discharge chamber which discharge gas leaves the discharge chamber through the aforementioned aperture, with an inlet into the ionization chamber for delivering sample gas to the ionization chamber, and with an outlet from the ionization chamber for carrying the mixed discharge gas and sample gas out of the ionization chamber. The discharge gas and sample gas mix then pass between the flat parallel emitter/collector plates before leaving the ionization chamber through the outlet.

Abstract: A method and circuit for measuring the pressure of a gas with a cold cathode ionization gauge by measuring the electrical resistance or conductance of the gauge to thus extend the measurement range of the gauge. Current into the gauge may be limited to a substantially constant value at pressures greater than about 10.sup.-6 Torr, for example, so that the gauge voltage varies monotonically with respect to pressure at pressures greater than 10.sup.-6 Torr.

Abstract: In a combustion process a fuel is mixed with an oxygen-containing gas in an adjustable ratio. This fuel-gas-mixture is burned and thereby an exhaust gas is produced. At least a part of the exhaust gas is collected and exposed to an ultra violet radiation source, thereby generating positive and negative charge carriers in the exhaust gas by means of a photoelectric charge separation process. The kind or amount of the positive and/or negative charge carriers is detected to produce a measurement value which reflects the amount and/or the charge of the carriers. Therefrom a control signal is derived and the mixture-ratio of the oxygen-containing gas and the fuel, the so-called .lambda.-factor, is adjusted in response to said control signal in order to improve the efficiency of the combustion and to reduce the emission of toxic substances.

Abstract: A bypass conduit is connected to a primary conduit and has tandem reservoirs formed therein. Continuous measurements are taken from the respective reservoirs of the electrical current generated by the relaxing fluid therein and flowing to ground. These respective measurements are inputted to a microcomputer through respective electrometer elements and converted into a single measure of charge density along with readings of the moisture, conductivity and temperature of the fluid. In a preferred embodiment, the fluid constitutes the oil (or other coolant) circulated in respective conduits between a power transformer and an external heat exchanger. The microcomputer may trigger an alarm (or a control mechanism) whenever the charge density generated in the circulating coolant reaches a predetermined threshold level, thereby avoiding a potential hazardous condition due to the build-up of static electrical charges in the protected transformer or other device.

Abstract: A diesel engine exhaust system is provided with a particulate trap for collecting the products of incomplete combustion during the engine power cycle. A sensing mechanism including an electrode downstream of the trap and a signal generating circuit provides a positive indication of occurrence of regeneration of the trap. Charged particles generated during regeneration induce a charge of the electrode, that charge activates the signal generating circuit and it, in turn, produces an indication external of the exhaust system that trap regeneration is occurring. That indication can be in the operator's compartment.

Abstract: A method and apparatus for classifying non-aqueous liquid suspensions of charged particles employs a large time-varying electric field applied to a suspension situated between capacitive test electrodes. A current waveform is produced that characterizes the suspension with respect to critical properties including concentration, mobility, and plating tendencies of the charged particles suspended therein. The approach is suitable for use with suspensions having relative permitivity constants of about 15 or less.

Abstract: An apparatus and method for providing a continuous and precise measurement of the number of soot particles emitted in the exhaust gas of a diesel engine. A pair of electrodes is provided in the exhaust gas flow and a voltage is applied across the electrodes so as to develop an electrical current across the electrodes indicative of the conductivity, and therefore the quantity, of the soot particles in the exhaust gas. In accordance with one embodiment of the invention, the electrodes are located in a diluting conduit provided with a pump for providing a constant volume of diluted exhaust gas between the electrodes. In accordance with another embodiment of the invention, the electrodes are located in the exhaust pipe of the diesel engine.

Abstract: An apparatus for monitoring the concentration levels of halogen gas in a gaseous atmosphere as confined in an enclosure over a relatively extended period of time. Such monitoring apparatus includes a sensor including first and second electrodes disposed to define a space therebetween through which the gaseous atmosphere flows and a voltage source for applying a voltage between the first and second electrodes whereby an ionization current flows to the first electrode. A control mechanism illustratively in the form of a programmed microcontroller monitors the ionization current collected by the first electrode as the output signal of the sensor, to determine an increase therein as would be indicative of a halogen leak. Upon determining an increase of the sensor output signal above a predetermined difference, the control mechanism removes the energization from the halogen sensor whereby the ionization current is terminated and the life of the sensor extended.

Abstract: Method and apparatus of charge distribution analysis insulating and semiconducting dielectric materials to measure by means of a Coulomb Balance surafce/subsurface space charge layers and the sign, mobility and polarizability of charge carriers. The technique includes measuring the force, attractive or repellent, between a bias electrode to which a voltage is applied and a dielectric material in a condensor half cell arrangement. An apparatus is provided for heating a sample for causing the generation of surface/subsurface charges, and then for applying an external potential while the sample is maintained at a high temperature. The effective mass of the sample is detected by determining the amount of force necessary to restore a balance arm, by which the sample is supported, to its original position, the alteration in position being due to attractive or repulsive electrostatic forces between the sample and the electrodes.

Abstract: The invention relates to a method and an arrangement for detecting ionizing current in an ignition circuit incorporated in the ignition system of an internal combustion engine, in which a measuring voltage is applied to the ignition circuit in at least one secondary winding, and in which a measuring device is used to detect the possible presence of an ionizing current in the ignition circuit. A low measuring voltage is applied during an engine start sequence, or alternatively, no measuring voltage at all, and a high measuring voltage is applied subsequent to the engine start. The invention thereby overcomes the problem existing when measuring ionizing currents of the spark plugs becoming coated with soot deposits as a result of the electrical voltage field which always exists between the electrodes of respective plugs. Such problem is particularly troublesome during an engine start sequence, since the deposits can prevent the engine from starting.

Abstract: Aerosol particles, resulting from the combustion of organic substances with insufficient oxygen supply, usually contain toxic, higher hydrocarbonic substances (e.g. tar) on their surface. These substances, e.g. tar, has the property to be photoelectrically more active than other substances contained in the atmosphere. In the method and apparatus according to the invention an aerosol, i.e. the carrier gas containing the particles to be characterized, is used which has been brought to at least one predetermined temperature sufficient for evaporation or decomposition or preventing condensation of molecules on particles of said aerosol that quench or enhance photoelectric activity. Such aerosol is exposed to electromagnetic radiation and, thereby, activated to electron emission. Thereafter the charge of the photoelectrically positively charged particles is determined by means of size selective filter means which are connected to current or charge measuring equipment.

Abstract: An apparatus for continuously adjusting the corona discharge currrent of a pair of electrodes exposed to an atmosphere of gaseous impurities, particularly halogen. The device consists of a power supply to cause a corona current to flow in a pair of electrodes in series with a summing resistor. Any change in the gaseous impurities which causes a change in the corona current is sampled in the resistor, detected, delayed, amplified and fed back in proper phase to the control element of the power supply to cause the corona current to remain constant. During the finite delay time the change in corona current causes an audible alarm to sound until the corona current is restored to the new level of impurity concentration. The corrective action is continuous for any level of impurity concentration.

Abstract: A detecting element (6) comprising a solid zirconia electrolyte (6a), a reference electrode (6d), a detecting electrode (6c) and a diffusion member (6a) is provided, and also a driving circuit (1b, 4) for impressing a voltage between the electrodes (6c, 6d) of said detecting element so as to detect the threshold current of an oxygen ion pumping current (I.sub.p) is provided. The output of this driving circuit is delivered as a continuous output (V.sub.o) of an air fuel ratio of fuel gas comprising al the regions of rich, stoichiometric and lean air fuel ratios. On the other hand, an I.sub.p detection resistor (Rs) for detecting the pumping current flowing between the input/output terminals of the driving circuit is provided. The opposite-end voltages (V.sub.a, V.sub.o) of this I.sub.p detection resistor are compared by a comparator (5), and a step signal corresponding to the stiochiometric air fuel ratio (.lambda.) is outputted from this comparator.

Abstract: A method and apparatus for determining ion flow imbalance. High-magnitude positive and negative potential sources, each having a high-magnitude potential output terminal, are provided. Two electrodes are adapted for positioning adjacent the location of ions, the electrodes having areas for exposure to the ions. A supply of operating potential is provided for the high-magnitude potential sources. The operating potential supply is switched to supply operating potential alternately between the high-magnitude potential sources. Neutral terminals are provided on each of the high-magnitude potential sources and the current flows from the neutral terminals of the high-magnitude potential sources to reference potential are sensed to determine the current flows to the electrodes.

Abstract: The invention provides a method for the quantitative and/or qualitative characterization of substances which are contained in a gaseous carrier medium. Modifications of the surface of small solid particles suspended in a carrier gas may be measured with very high sensitivity by the application of the photoelectric effect. Thereby, an aerosol is chemically modified, e.g. by admixing a gaseous agent or a gas mixture, or by subjecting it to an electromagnetic radiation, and subsequently the resulting variation of the photoelectron emission from the suspended particles is recorded. By measuring the variation of the photoelectric effect during the admixing or variation of a gaseous agent to the aerosol to be examined or during a variation of the electromagnetic radiation, to which the aerosol to be examined is subjected, the suspended particles may be classified in one or several steps.

Abstract: In the known electrical mobility analyzer, a novel means for charged particle detection instead of measuring the low level current carried by the particles is provided. This detection is based on the burst corona occuring from a positive corona electrode applied with a voltage slightly lower than its onset voltage at an instant when a negatively charged particle arrives at the tip of the corona electrode. This detection detects and counts the burst corona pulses produced by the particles negatively precharged.

Abstract: A relatively simple and compact device is disclosed for monitoring ion imbalance at a preselected, or work, area. A collector is utilized that is charged due to ions contiguous thereto, with the charge at the collector being processed, preferably utilizing a charging capacitor and operational amplifier, to provide an output signal indicative of ion imbalance at the preselected area, which output signal is then utilized to produce an indication of ion imbalance at the preselected area and/or to correct the ion output of an ion generator directing ions toward the preselected area. A pair of collectors can be utilized to separately sense positive and negative ions separately generated by an ion generator with the acquired charge on each collector being separately processed, and the indication of ion imbalance can be accomplished utilizing a meter and/or alarm.

Abstract: A device for gas detection through ion mobility segregation by mobility ranges includes a flow tube through which a sample of atmospheric air with possible contaminant gases flow. Ions formed of gases in the air and the possible contaminant gases are segregated by ion mobility range in either a first, second or subsequent electric field positioned along the flow tube. The ions are collected on an anode or cathode of each electric field. The ions of the gases striking an anode or cathode by charge transfer induce a detection current, the measure of which indicates the presence of gases of interest. A method for detecting a gas by ion mobility segregation is also described.

Abstract: The sensor 1 has its point of operation towards the Townsend discharge zone, and the collection of ions causes an increase in the current passing through it. The electrodes of the sensor are formed by wires bent in the shape of an alpha.

Abstract: An apparatus is disclosed for analyzing trace elements in a gas sample. A unique feedback system is provided for accurately regulating and sensing the pressure supplied to the ion chamber of the device. The feedback system is capable of compensating for a wide range of input gas pressures. The apparatus also includes an improved closed ion source which is resistant to corrosion and aids in the reduction of noise. In addition, a method is disclosed to calibrate the detector for accurately scaling the measurements of trace elements.

Abstract: An inflammable gas detector for detecting an inflammable gas wherein the inflammable gas detector is of the platinum-alloy wire type which forms part of a resistance bridge network to operate in a condition for maximum sensitivity by preadjusting the voltage at the terminals of the inflammable gas detector in accordance with the desired type of gas to be detected, then utilizing the signals supplied by the detector in the resistance bridge network to bring the cathode of a diode to the threshold limit value and at the same time to render two further diodes conductive to activate a signal or control relay or both.

Abstract: Ionization of a medium being monitored is caused by an electric arc between a first pair of electrodes, while the conductivity of the medium between two measuring electrodes controls at least one feedback circuit which indicates relative rates of decay of the ions, as a function of variations in the number and mobility of ionized particles in the ambient medium.