Abstract: The present disclosure provides apparatuses for collecting aerosol samples by ionizing an air sample at different degrees. An air flow is generated through a cavity in which at least one corona wire is disposed and electrically charged to form a corona therearound. At least one grounded sample collection plate is provided downstream of the at least one corona wire so that aerosol ions generated within the corona are deposited on the at least one grounded sample collection plate. A plurality of aerosol samples ionized to different degrees can be generated. The at least one corona wire may be perpendicular to the direction of the flow, or may be parallel to the direction of the flow. The apparatus can include a serial connection of a plurality of stages such that each stage is capable of generating at least one aerosol sample, and the air flow passes through the plurality of stages serially.

Abstract: Techniques and devices are disclosed for detecting particle composition. In one aspect, a method performed by a detector to detect particles includes receiving particles at an aerosol inlet of the detector. The method includes carrying the received particles within a stream of gas and charging the particles within the stream of gas using a charger to have a charge. The method includes transporting the charged particles to a location of a collection electrode. The method includes biasing the collection electrode to a voltage using a high-voltage supply to attract either negatively or positively charged particles, and analyzing the particles.

Abstract: The invention relates to a device and method for measuring the density of a plasma by determining an impulse response to a high-frequency signal coupled into a plasma. The density, electron temperature and/or collision frequency as a function of the impulse response can be determined. A probe having a probe head and a probe shaft can be introduced into the plasma, wherein the probe shaft is connected to a signal generator for electrically coupling a high-frequency signal into the probe head. The probe core is enclosed by the jacket and has at its surface mutually insulated electrode areas of opposite polarity. A balun is arranged at the transition between the probe head and an electrically unbalanced high-frequency signal feed to convert electrically unbalanced signals into balanced signals.

Abstract: A scalable vacuum photosensor configured to simplify mass production with a housing having an evacuated first side at an ultrahigh vacuum and a second side which does not require high vacuum. The first side of the device is sealed to a base plate, having a central electron readout element, using an oxide-free sealing technique, with the deposited sealing areas serving as high voltage throughputs from the first to second sides. A conductive photocathode layer on the transparent first side converts photons to photoelectrons and concentrates the photoelectrons upon the readout. The first and second sides together form an electrostatic lens for accelerating and focusing photoelectrons upon the readout, preferably having a scintillator which generates secondary light measured by an optical detector in the second side of the housing.

Abstract: A semiconductor device structure is embedded within a semiconductor chip that calibrates a photon-emission luminosity scale by running multiple known currents through the device. The method comprises embedding at least one photon emission device in an integrated circuit having at least one functional device. A control current is applied to the at least one photon emission device. The photon emission intensity produced by the at least one photon emission device is captured. The current density of the at least one photon emission device is calculated. A test current is applied to the at least one functional device. The photon emission intensity produced by the at least one functional device is captured. The current density of the at least one functional device is estimated based on a comparison with the calculated current density of the at least one photon emission device.

Abstract: A fine particle measurement system including a primary-side power supply circuit connected to a primary side of an isolation transformer, a control circuit configured to control the primary-side power supply circuit, a first current measurement circuit configured to transmit to the control circuit a first signal indicating a first current that flows from a trapping unit toward a secondary-side reference potential line, and a second current measurement circuit configured to transmit to the control circuit a second signal indicating a second current corresponding to the amount of ions that are not trapped by the trapping unit. The control circuit adjusts the electrical power supplied to the ion generating unit based on the first current and measures the amount of the fine particles in the gas based on the second current. Further, the first current measurement circuit includes an isolation amplifier and amplifies the first signal via the isolation amplifier and transmits the first signal to the control circuit.

Abstract: The present invention provides an ionization detector having a base having an enclosed chamber. The enclosed chamber has a first end and a second end. The detector also includes a first outlet which is a source of an excitable medium. A second outlet is provided which functions a source of an analyte that is transported by a carrier gas. An ionization source for creating a discharge from said excitable medium is also provided. The collector electrode generates a time dependent current based on its interaction with ionized analytes from which the analyte may be detected.

Abstract: The disclosure features systems and methods for detecting organic compounds that include: (a) a transfer line; (b) a probe connected to a first end of the transfer line, the probe including an inlet port and a membrane positioned across an opening in the inlet port; (c) an analysis unit connected to a second end of the transfer line; and (d) an electronic controller. The analysis unit can include a valve featuring multiple ports, a first detection unit configured to measure a photoionization current, and a second detection unit configured to identify chemical compounds, and a trap configured to condense chemical compounds from a vapor phase to a liquid phase. The electronic controller is connected to the valve, the first and second detection units, and the trap.

Abstract: A particle count measurement device includes a preprocessing section configured to place an aerosol introduced into a measurement region in an electrical state of any of a neutralized state, a positively charged state or a negatively charged state, a unipolar charging section configured to place the aerosol which has been introduced in an electrical state different from at a time of introduction, an ion trap arranged on a downstream of the unipolar charging section in terms of a flow of the aerosol for generating an electric field that draws only gas ions in the aerosol, an exhaust mechanism configured to discharge the aerosol from the measurement region at a constant flow rate, and an ammeter for detecting, as a measurement value corresponding to a particle count concentration, a difference between current supplied by the unipolar charging section and current flowing into the ion trap.

Abstract: Apparatus comprising a module for detecting a single nucleotide polymorphism, SNP, within a genome and comprising: four reaction chambers for receiving a fluid sample, the reaction chambers each containing a different one of the bases A, C, G, T, and a primer; a reference electrode which in use is immersed in said fluid sample; a pair of Ion Sensitive Field Effect Transistors, ISFETs, associated with each reaction chamber, the ISFETs of each pair comprising respective sensing membranes, or a common sensing membrane, exposed within the associated reaction chamber; and a plurality of difference detectors, each difference detector having a pair of inputs coupled respectively to outputs of ISFETs associated with different reaction chambers.

Abstract: A powder sensor includes a piezoelectric element, an oscillator circuit, a phase determination circuit, and a powder presence/absence determination circuit. The oscillator circuit applies to the piezoelectric element an output signal having a frequency equal to or near a resonance frequency of the piezoelectric element. The phase determination circuit determines phase of a terminal voltage of the piezoelectric element relative to phase of the output signal from the oscillator circuit. The powder presence/absence determination circuit determines that powder is absent if the phase determination circuit determines, n consecutive times (where “n” is an arbitrary integer satisfying n?2), that the phase of the terminal voltage of the piezoelectric element, relative to the phase of the output signal from the oscillator circuit, satisfies a predetermined condition.

Abstract: A discharge ionization current detector capable of supplying plasma gas in large quantity to stabilize plasma simultaneously with lowering the sample dilution ratio to improve detection sensitivity is provided. A gas supply pipe 7 for supplying a plasma gas, which also functions as a dilution gas, is connected to a point near the connecting section of a first gas passage 3 having electrodes 4-6 for plasma generation and a second gas passage having electrodes 16 and 17 for ion detection. A first gas discharge pipe 8 is connected to the other end of the first gas passage 3, and a second gas discharge pipe 13 is connected to the other end of the second gas passage 11. Flow controllers 9 and 14 are provided in the gas discharge pipes 8 and 13, respectively. The flow rate of the gas passing through a plasma generation area and that of the gas passing through an ion current detection area can be independently regulated.

Abstract: An aging treatment is performed by using cleaning gas obtained by mixing inert gas, as an impurity, to plasma gas. Plasma generation by dielectric-barrier discharge is performed until a predetermined period of time has elapsed by applying high AC voltage to an electrode while supplying the cleaning gas to a dielectric tube from a gas inlet.

Abstract: A pulsed discharge helium ionization detector for gas chromatography with multiple combined bias/collecting electrodes.

Abstract: The invention relates to an electrochemical sensor integrated on a substrate, the electrochemical sensor including: a field effect transistor integrated on the substrate and having a source, gate and drain connections, said gate of the field effect transistor including: a sensing gate conductively coupled to a sensing electrode; and a bias gate, wherein the sensing gate is capacitively coupled to the bias gate and the bias gate is capacitively coupled to the substrate.

Abstract: An analysis device comprising a discharge ionization current detector, a plasma gas supply section, a sample gas supply section, a flow rate setting condition holding section and a gas flow rate setting means controller. The flow rate setting condition holding section holds, as a flow rate setting condition, a relationship between a sample gas supply flow rate from the sample gas supply section and a supply flow rate of plasma gas to be set with respect to the sample gas supply flow rate and the gas flow rate controller is configured to set a plasma gas supply flow rate from the plasma gas supply section to a flow rate according to the sample gas supply flow rate, based on the flow rate setting condition held in the flow rate setting condition holding section.

Abstract: A particulate matter sensor includes first and second electrodes spaced from each other with a bias resistor connected between the first and second electrodes. The particulate matter sensor allows an open circuit fault condition in the sensor or in the connectors or wiring to the sensor to be detected. A sensing system using the particulate matter sensor and a method for diagnosing faults in a sensing system are also provided.

Abstract: A testing device for solid oxide fuel cell (SOFC) is disclosed. The testing device which combines the original cell housing with a four-point probe equipment is set for measuring SOFC MEA. The current collectors on anode and cathode in the original cell housing are respectively replaced by four independent probe units. They are not only to collect current but also to become measuring probes. Therefore, the lateral impedance of anode and cathode can be measured. Furthermore, the local characteristics are examined by open circuit voltage (OCV), I-V curve, and electrochemical impedance spectroscopy (EIS) measurements. The results show that the lateral impedance is substantially varied with temperatures. The distributions of OCV, current density, EIS and cell voltage in long-term test at the center of the cell are different from the edge.

Abstract: A fast response output signal circuit (10) for a cold cathode gauge is provided to produce a fast response output signal (48) in addition to a voltage output signal (40) that is representative of the pressure in the cold cathode gauge. The fast response output signal (48) is either on or off, thus can be used to trigger a closing of an isolation valve or other responsive action upon a change in pressure that attains or exceeds a certain set point threshold. The fast response output signal is produced and processed with analog circuits, but the set point is produced with a microprocessor. The voltage output signal can be produced as a logarithmic function of the pressure.

Abstract: Methods and apparatus for providing an air sampling system with first and second PID sensors to discriminate ammonia measurements. In one embodiment, air samples are taken from a vivarium environment to determine ammonia levels for controlling air flow to the vivarium.

Abstract: A photo ionization detector (PID) is provided for selectively determining various compounds or gases present in a breath sample. The PID, comprises a substrate comprising a gas ionization chamber, at least one pair of ion sensing electrodes, and at least one amplifying circuit; and an ultraviolet (UV) ionization source to transmit a UV light beam into the gas ionization chamber. A system comprises the PID is also provided. A method of detecting a response pattern for various compounds or gases in breath using PID is also provided.

Abstract: An electrochemical sensor allows even extremely small quantities or concentrations of a target chemical substance to be detected or quantified with a high precision in a particularly reliable manner. The novel sensor has a detector zone formed by nanoparticles which are embedded in a matrix and have a higher electric conductivity than the matrix material. The electric conductivity of the zone is determined by electron tunneling, ionization or hopping processes among the nanoparticles and by the electrochemical interaction thereof with a target substance to be detected.

Abstract: Methods and systems for detecting a change in the state of plasma confinement within a capacitively coupled RF driven plasma processing chamber are disclosed. In one or more embodiments, the plasma unconfinement detection methods employ an analog or digital circuit that can actively poll the RF voltage at the powered electrode in the form of an Electrostatic Chuck (ESC) as well as the open loop response of the power supply (PSU) responsible for chucking a wafer to ESC. The circuit provides a means detecting both a change in RF voltage delivered to the ESC as well as a change in the open loop response of the PSU. By simultaneously monitoring these electrical signals, the disclosed algorithm can detect when plasma changes from a confined to an unconfined state.

Abstract: A detector for gas chromatography using two or more ionization sources within a single body to separately provide ionization energy to a column gas eluent to provide electrical discharge to two or more collecting electrodes provides improved selectivity and may be so used. Use is made of combined bias/collecting electrodes or of sets of separated bias and collecting electrodes. The use of multiple ionization sources permits generation of multiple detector outputs from within a common body and of a common constituent flow. The ionization sources and any applicable discharge gas and dopant may be selected based on desired selectivity.

Abstract: In various embodiments of the invention, a cargo container can be monitored at appropriate time intervals to determine that no controlled substances have been shipped with the cargo in the container. The monitoring utilizes reactive species produced from an atmospheric analyzer to ionize analyte molecules present in the container which are then analyzed by an appropriate spectroscopy system. In an embodiment of the invention, a sorbent surface can be used to absorb, adsorb or condense analyte molecules within the container whereafter the sorbent surface can be interrogated with the reactive species to generate analyte species characteristic of the contents of the container.

Abstract: A particulate matter detection element includes a capacitance component disposed in parallel with a detected resistance RSEN. A direct current-power source that supplies a direct current (IDC) for particulate matter detection, and an alternating-current power source that supplies an alternating current (IAC) for disconnection detection are provided.

Abstract: An ion mobility gas detector apparatus including a detector core, an inlet gas path, an exhaust gas path, a source of diluent gas, and at least one or more sensors for measuring temperature, pressure and humidity of gas streams. Further included is a mixing mechanism adapted to mix at least first and second gas streams in response to one or more sensor measurements. A controller is provided for applying drive signals to the detector core.

Abstract: In a particle beam therapy system which scans a particle beam and irradiates the particle beam to an irradiation position of an irradiation subject and has a dose monitoring device for measuring a dose of the particle beam and an ionization chamber smaller than the dose monitoring device, the ionization chamber measuring a dose of a particle beam passing through the dose monitoring device, the dose of the particle beam irradiated by the dose monitoring device is measured; the dose of the particle beam passing through the dose monitoring device is measured by the small ionization chamber; and a correction coefficient of the dose measured by the dose monitoring device corresponding to the irradiation position is found based on the dose of the particle beam measured by the small ionization chamber.

Abstract: An ionized gas detector includes at least a pair of ion detecting electrodes that detect ions of the ionized measuring-subject gas, an electrode-voltage applying unit that applies a given voltage to the ion detecting electrodes, the electrode-voltage applying unit being configured to be capable of reversing its voltage polarity, a charge amplifier circuit having a charge capacitor that accumulates electric charges generated by voltage application by the electrode-voltage applying unit, an ion current calculating unit that calculates the value of an ion current of ions of the measuring-subject gas, based on a time-dependent change of the volume of electric charges accumulated in the charge capacitor of the charge amplifier circuit, and a concentration determining unit that determines the concentration of the measuring-subject gas, based on an ion current value calculated by the ion current calculating unit.

Abstract: A detector for gas chromatography using two ionization sources within a single body to separately provide ionization energy to a column gas eluent to provide electrical discharge to two or more collecting electrodes provides improved selectivity and may be so used. Use is made of combined bias/collecting electrodes. The use of two ionization sources permits generation of two detector outputs from within a common body and of a common constituent flow. The ionization sources and any applicable discharge gas and dopant may be selected based on desired selectivity.

Abstract: A technique for reducing an electromagnetic noise entering an electrode or a drift of a signal due to a fluctuation in the ambient temperature is provided to improve the S/N ratio of a signal originating from a component of interest. A dummy electrode having the same structure as an ion-collecting electrode is provided within a lower gas passage at a position where dilution gas with no sample gas mixed therein flows. A differential amplifier is provided to perform differential detection between output A of a current amplifier connected to the ion-collecting electrode and output B of a current amplifier connected to the dummy electrode. The differential signal is free from a common mode noise or drift and hence accurately reflects the amount of the component of interest.

Abstract: There is provided a fine particle detection system with a fine particle sensor, a cable and a sensor drive control device. The fine particle sensor has an ion source unit with first and second electrodes, a particle charging unit and inner and outer sensor casings. The cable has a power supply wiring line connected to the second electrode, an inner shield line electrically continuous with the inner sensor casing and an outer shield line electrically continuous with the outer sensor casing. The sensor drive control device has an ion-source power supply circuit, a signal current detection circuit, an inner circuit casing electrically continuous with a first output terminal of the ion-source power supply circuit and surrounding the ion-source power supply circuit and an outer circuit casing connected to the ground potential and shielding the ion-source power supply circuit, the signal current detection circuit and the inner circuit casing.

Abstract: A system and method is provided for simultaneous ion current sensing and gas analysis. The system acquires an ion current signal and analyzes the composition of a corresponding gas sample.

Abstract: Methods and systems for detecting and/or collecting particles are disclosed. At least some of the particles are electrically charged by a charger (122). At least some of the charged particles are collected by a collector (140). Information indicating the number of the detected/collected particles based on measured electrical charges of the charged particles is obtained by a processor (170).

Abstract: A discharge ionization current detector using a low-frequency dielectric barrier discharge with an improved S/N ratio is provided. A current detector 20 is disposed between an excitation high-voltage power source 8 and a discharge electrode 5 to detect a discharge current flowing in pulses due to plasma generation. The detection signal of the current detector 20 and an output signal from a current amplifier 18 for amplifying an ion current are inputted into an output extraction unit 21. The output extraction unit 21 detects a precipitous-rise portion of the discharge current detection signal and generates a trigger signal, and then extracts an ion current signal for a predetermined time period from the trigger signal. This can remove an influence of a noise appearing in a signal during a time period where no plasma emission is generated, thereby improving the S/N ratio of the detection signal.

Abstract: A discharge ionization current detector using a low-frequency barrier discharge is provided to improve the linearity of detection sensitivity with respect to a sample introduction amount. From a lower end of a lower gas passage connected to a lower end of an upper gas passage, a dilution gas is supplied upward against a downward flow of a plasma gas. A gas discharge passage for discharging a plasma gas, the dilution gas and a sample gas is arranged between an ion-collecting electrode and a bias voltage application electrode. The sample gas introduced through a capillary tube is mixed with the plasma gas and the dilution gas due to a disturbed flow generated by collision of the plasma gas and the dilution gas. The sample component is efficiently ionized by light from the plasma without undergoing light-shielding effect of concentrated sample components.

Abstract: A method for tracking the deterioration of the insulators in a rotating machine, a method for preventive maintenance of these machines using this tracking and devices using the tracking method is presented.

Abstract: The invention relates to anion gauge for determining a total integrated concentration of a substance having a molecular weight falling into a pre-determined range of molecular weights in a gas sample. The anion gauge includes an ionization region in a vicinity of the ionization source; an accelerator for generating a flow of ionized molecules; a mass filter for intercepting the flow for separating ions having the molecular weight falling into the pre-determined range from the ionized molecules and a detector for generating a signal representative of the total integrated concentration of such ions present in the gas sample. The invention further relates to a lithographic apparatus and a method for determining a total integrated concentration of a substance having a molecular weight falling into a pre-determined range of molecular weights in a gas sample.

Abstract: A low-OH-content quartz glass with an OH content equal to or lower than 5 ppm is used as a cylindrical tube (2) covering the surface of metallic plasma generation electrodes (4, 5 and 6) for generating a low-frequency barrier discharge. It has been found that, in the low-frequency barrier discharge, hydrogen and oxygen originating from the OH contained in a dielectric material are released into plasma gas for a long period of time, constituting a primary cause of an increase in the baseline current. The use of a low-OH-content quartz glass dramatically lowers the baseline current and thereby improves the S/N ratio and the detection limit.

Abstract: A particulate matter detection device that detects the diameter and the amount of particulates in exhaust gas while reducing detection error caused by deterioration such as the deterioration of electrodes is provided. In the particulate matter detection device, which measures particulates in a gaseous body, AC voltages having different frequencies are applied to a pair of electrodes disposed apart from each other. The resulting impedances to the different frequencies are detected. A resistance component and/or a capacitance component of the impedances to the different frequencies are calculated. The average diameter and/or the number of particulates in the gaseous body are estimated in accordance with changes in the resistance component and/or the capacitance component.

Abstract: In various embodiments of the invention, a cargo container can be monitored at appropriate time intervals to determine that no controlled substances have been shipped with the cargo in the container. The monitoring utilizes reactive species produced from an atmospheric analyzer to ionize analyte molecules present in the container which are then analyzed by an appropriate spectroscopy system. In an embodiment of the invention, a sorbent surface can be used to absorb, adsorb or condense analyte molecules within the container whereafter the sorbent surface can be interrogated with the reactive species to generate analyte species characteristic of the contents of the container.

Abstract: A detector for gas chromatography using two ionization sources within a single body to separately provide ionization energy to a column gas eluent to provide electrical discharge to two or more collecting electrodes provides improved selectivity and may be so used. Use is made of combined bias/collecting electrodes. The use of two ionization sources permits generation of two detector outputs from within a common body and of a common constituent flow. The ionization sources and any applicable discharge gas and dopant may be selected based on desired selectivity.

Abstract: An apparatus for determining a thickness change of thermal interface material (TIM) disposed between first and second elements is provided. The apparatus includes a first part movable with the first element in a movement direction along which the TIM thickness is to be determined, a second part movable with the second element in the movement direction and a sensor to measure a distance between the first and second parts in the movement direction, the measured distance being related to the TIM thickness change.

Abstract: A process for measuring particle concentrations in a gas using an ejector for producing an essentially constant sample flow and for efficient mixing of the particle-containing sample and essentially clean, ionized gas. The invention also relates to an apparatus implementing such process. The process and the apparatus can be utilized for example in measuring particle concentrations in an exhaust system of a combustion engine.

Abstract: Various environmental systems are disclosed. In accordance with one of the systems, a first and second valve are provided. The valves provide a first air flow path from an air pump to a photo-ionization detector is provided through a pre-filter. The valves also provide a second air flow path from the air pump to the photo-ionization detector so that the pre-filter is isolated from its environmental surroundings. Various other arrangements of environmental monitoring systems with one or more pre-filters are also disclosed.

Abstract: An integrated sensor of volatile organic gas can include a photoionization detector (PID) and one or more additional detectors such as an infrared detector, a catalytic combustion detector, or an electrochemical detector. One embodiment includes a methane detector that allows correction of the PID measurements for the interference of methane with the PID and/or allows a combination of measurements of the sensors to measure a total hydrocarbon concentration. A further sensor of non-hydrocarbon quenching gases such as carbon dioxide may also be used in correction of the PID measurements.

Abstract: An ionization gauge includes an electron generator array that includes a microchannel plate that includes an electron generating portion of the microchannel plate comprising a source for generating seed electrons and an electron multiplier portion of the microchannel plate, responsive to the seed electrons generated by the electron generating portion, that multiplies the electrons. The ionization gauge includes an ionization volume in which the electrons impact a gaseous species, and a collector electrode for collecting ions formed by the impact between the electrons and gas species. The collector electrode can be surrounded by the anode, or the ionization gauge can be formed with multiple collector electrodes. The source of electrons can provide for a spontaneous emission of electrons, where the electrons are multiplied in a cascade.

Abstract: Apparatus and associate method including a substrate having a first surface; a lid having a second surface; at least one spacer element interposed between the substrate and the lid so as to maintain the first and second surface spaced apart; a partition with a plurality of nanometric size through-openings interposed between the spacer element and the lid defining a first chamber a second chamber fluidically connected together through at least one of the openings; the substrate has at least one first electrode on the first surface and the lid has a second electrode, the first electrode being configured to detect an electric signal associated to the passage of one of said particles through one of the through-openings.

Abstract: To provide a discharge ionization current detector 3, where a partition 13a in which a through hole for penetrating a tubule 24 for introducing a sample gas is created is provided between a collector electrode 20 and an outlet for discharging a gas 26 so that a gas for generating plasma that has been generated by electrodes for discharge 15, 16 and 17 passes through a gap between the through hole and the tubule 24 so as to be directed towards the outlet for discharging a gas, and thus, the air that has entered from the other side 25 of the partition cannot pass through the through hole in the opposite direction.

Abstract: This invention provides a sensor having such a structure that the area in which a sensor electrode comes into contact with a liquid, a mist or a gas containing an analyte has been previously specified. The sensor comprises at least an electroconductive first electrode, an electroconductive second electrode, electroconductive first and second wirings connected to the first and second electrodes, and an insulating part for insulating the first and second wirings from each other and from a liquid, a mist or a gas containing the analyte. The insulating part is formed of an organic material. In the first and second electrodes, at least the surface, which comes into contact with a liquid, a mist or a gas containing the analyte, is formed of a material which is insoluble in a liquid or a mist containing the analyte, or is not attacked by a gas containing the analyte.