Abstract: A system and method for utilizing a carbide-derived carbon (CDC) fiber in solid-phase micro extraction. Optically pumping the carbide-derived carbon (CDC) fiber, as compared to using thermal desorption, enhances performance of the system. CDC provides for a broad based sorbent that is insensitive to high humidity. Optical pumping may be done axially or radially on a modified gas chromatography needle. In some cases, staged, or pulsed, optical pumping is used to drive off solvent or other lower boiling compounds first and then the desorption of the remaining analytes is cleaner and the instrumentation is less likely to be overloaded.

Abstract: An analysis apparatus column oven equipped with a plurality of columns is capable of efficiently performing heat conduction on column basis, recognizing a column cartridge that holds a column, and being easily exchanged on column basis. The column change mechanism includes a ferrule, a movable ferrule connector, a pipe, a fastener pull, a fastener fitting, a column cartridge presser, a slide guide, an RFID reader, a fixed wall, a column changer heat insulating member, a fixed bottom plate, a receiver, and a fixed fitting. A plurality of column cartridges can be installed in the heat block, and are in contact with the column heat block to control the temperature in the column cartridges. The column cartridge is fixed between left and right column change mechanisms, and when the fixed column cartridge is opened, the column change mechanism on the left side is moved leftward and opened.

Abstract: A detector for a liquid chromatograph, includes a detector that detects components in liquid, a pipe that guides liquid to the detector, a casing that contains at least part of the pipe and the detector and has a bottom portion, and a thermal insulator provided on the bottom portion in the casing, wherein a discharge port is provided in the bottom portion of the casing, the thermal insulator has an upper surface and a lower surface, a first opening is provided in the upper surface of the thermal insulator, and a second opening is provided in the lower surface of the thermal insulator to overlap with the discharge port in a plan view, a flow path that guides liquid from the first opening to the second opening is provided in the thermal insulator, and the flow path has a bend portion.

Abstract: Provided is a component extraction device for eluting a component in a sample into a supercritical fluid to extract the component from the sample. The component extraction device includes: a container rack including a plurality of sample container holding parts; a rack mounting stand including a mounting section on which the container rack is mounted; a plurality of heating blocks fixedly disposed on a mounting face of the mounting section at positions respectively corresponding to the plurality of sample container holding parts; a plurality of temperature sensors each configured to detect a temperature of each of the plurality of heating blocks; and a control unit configured to respectively control the plurality of heating blocks, based on results of detection by the plurality of temperature sensors.

Abstract: A gas chromatograph with a positioning system for the inlet liner and the column includes a column and the positioning system for the inlet liner and the column. The column is configured for gas chromatography. Wherein, the positioning system for the inlet liner and the column is configured to position the inlet liner and the column with respect to one another. The positioning system for the inlet liner and the column is configured to repeatably and optimally position the inlet liner and the column with respect to one another. The positioning system for the inlet liner and the column positions the inlet liner in a perpendicular orientation to the column.

Abstract: A control system for controlling extraction of landfill gas from a landfill via a gas extraction system comprising well piping, the landfill gas having a first temperature when extracted, the control system comprising: a gas composition chamber coupled to the well piping and comprising at least one sensor configured to measure one or more characteristics of a landfill gas sample in the gas composition chamber; a temperature control mechanism configured to heat the landfill gas sample in the gas composition chamber to a second temperature at least a threshold amount greater than the first temperature; and a controller configured to control the at least one sensor to measure the one or more characteristics of the landfill gas sample in the gas composition chamber when a temperature of the landfill gas sample in the gas composition chamber is at least the threshold amount greater than the first temperature.

Abstract: The disclosure relates to a sensor for detecting and/or analysing a gas. The sensor comprises a substrate, a recess or opening arranged in the substrate, a first bridge structure and a second bridge structure. The first bridge structure and the second bridge structure extend over said recess or opening and are anchored in the substrate. The first bridge structure forms a first hotplate and comprises a first patch of sensing material, in particular of a metal oxide material, arranged on the first hotplate, electrodes adapted to measure an electrical property of the first patch and a heater adapted to heat the first hotplate. The second bridge structure comprises a temperature sensor. The sensor comprises circuitry for driving the heater and for processing signals from the electrodes and the temperature sensor.

Abstract: In a capillary heating type thermal type mass flow meter comprising a sensor configured to detect temperature and pressure of a fluid and a correction means configured to correct a mass flow rate based on said temperature and said pressure, change rates of the mass flow rate of the fluid with respect to temperature and pressure have been previously acquired, and the mass flow rate is corrected based on said temperature and said pressure as well as these change rates. Thereby, the mass flow rate can be measured accurately and simply even when the temperature and/or pressure of the fluid, whose mass flow rate is to be measured, change.

Abstract: A method of comprising: introducing a sample volume into an inlet end of a liquid chromatography column, wherein the liquid chromatography column includes a focusing segment proximal to the inlet end of the liquid chromatography column and a separation segment proximal to an elute outlet of the liquid chromatography column; maintaining only the focusing segment at a first temperature as the sample is introduced into the focusing segment; and subsequently heating the focusing segment to a second temperature that is higher than the first temperature after the entire sample volume has been introduced into the focusing segment.

Abstract: A thermal conductivity detector for a gas chromatograph includes a heatable resistive detector element configured to be physically arranged in a flow of analytes eluting from a chromatography column and electrically arranged together with resistors in separate arms of a measuring bridge, wherein to provide a new configuration of the thermal conductivity detector to allow high detector sensitivity and to meet intrinsic safety requirements, the detector element includes at least two equal detector sub-elements that are configured to be physically arranged in series in the flow of analytes and electrically arranged in parallel with each other, where the detector element in one arm and a reference resistor in the other arm of the same half of the measuring bridge are configured such that the total resistance of the parallel detector sub-elements at operating temperature is at least approximately equal to the resistance of the reference resistor.

Abstract: Certain embodiments described herein are directed to inserts and ion sources. In some examples, an insert can comprise a positioning guide configured to provide for visual positioning of a chromatography column under the positioning guide. In other examples, an ion source configured with an aperture to couple to a carrier tube to render the ion source non-removable from an instrument housing when the carrier tube is coupled to the ion source is described.

Abstract: Provided is a trace gas measurement apparatus for electrical equipment that includes at least one sample cell configured to collect an oil sample from the electrical equipment. The sample cell having an oil receiving portion for receiving an oil sample, at least one perforated or porous sheet within a head space thereof for receiving the oil sample from the oil receiving portion, housing the oil sample thereon, and separating a new oil sample received from an existing oil sample within the at least one sample cell. The trace gas measurement apparatus also includes an oil pump for selectively pumping oil into and out of the sample cell, and a control module controlling operation of the oil pump, to adjust an oil level and air pressure within the sample cell, for performing an extraction process of trace gases within the oil sample.

Abstract: An apparatus for heating a flowing fluid includes a tubing assembly, a heater block made of thermally conductive material, and a heater cartridge in thermal communication with the heater block. The heater cartridge is configured to provide heat to the heater block for transfer to fluid flowing through the tubing assembly. The apparatus also includes circuitry in electrical communication with the heater cartridge to control a temperature of the heater block by controlling operation of the heater cartridge. The heater block is die-cast about the tubing assembly.

Abstract: A control apparatus for an internal combustion engine having a means for performing a model calculation to calculate, as an exhaust temperature calculation value, the temperature of exhaust gas in an exhaust branch tube at the time of starting an engine, using a model representing the temperature behavior of the exhaust gas in the exhaust branch tube during stop of an engine; and an exhaust temperature actual measurement value output means for detecting the temperature of exhaust gas in the exhaust branch tube, and outputting the detected temperature as an exhaust temperature actual measurement value, wherein the model includes at least one parameter.

Abstract: A system and method for rapidly determining ambient temperature in a fluid-analyte meter. The meter includes a housing defining an interior space and an area for receiving a fluid sample. A processor and a first temperature sensor are disposed within the interior space of said the housing. A second temperature sensor is disposed on the housing. One or more processors are configured to determine a first temperature value from temperature data received from the first temperature sensor. The processor(s) are also configured to apply a variable current to a temperature-adjustment source such that the second temperature sensor is adjusted to a predetermined steady-state temperature value different from the first temperature value. The processor(s) are further configured to determine an ambient temperature of an exterior space of the housing based on the applied variable current, pre-determined steady-state temperature, and received first temperature values.

Abstract: Disclosed is a gas chromatography chip including: a substrate having an upper substrate and a lower substrate; a gas supply connecting part formed on one plane of one surface of the substrate or on one plane of an opposite surface of the substrate; a gas discharge connecting part formed another plane of the one surface of the substrate or on another plane of the opposite surface of the substrate; a micro channel continuously extending from the gas supply connecting part to the gas discharge connecting part to form a micro channel part and having a circular cross-section; at least two position alignment markers formed on one surface or an opposite surface of the opposite surfaces of the substrate; and a heat transfer part and a temperature control unit for controlling a temperature of the substrate.

Abstract: Methods and systems for cooling gas chromatography ovens that comprise a housing having a fluid entry and a sleeve positioned within the housing to provide a fluid gap between the inner surface of the housing and the outer surface of the sleeve, where the sleeve is coupled to the fluid entry, and where a cooling fluid from the fluid entry traverses the inner layer of the sleeve and thereafter the outer layer of the sleeve via the fluid gap. In one embodiment, the housing includes at least one adjustable fluid exit, and the fluid gap is in fluid communications with the fluid exit(s). The fluid entry and the sleeve can be concentric, and the sleeve can include a heating element. A fan can be positioned to drive the cooling fluid from the fluid entry.

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: New sensors and methods for qualitative and quantitative analysis of multiple gaseous substances simultaneously with both high selectivity and high sensitivity are provided. The new sensors rely on a characteristic difference in energy between the interaction of a particular substance with a catalyst coated heat transfer device (HTD) and a non-catalyst coated (or one coated with a different catalyst) reference HTD. Molecular detection is achieved by an exothermic or endothermic chemical or physical reaction between the catalytic surface of the sensor and the molecule, tending to induce a temperature change of the sensor. Both high temperature and non-destructive low temperature detection are possible. The magnitude and rate of endothermic or exothermic heat transfer from a specific molecule-catalyst interaction is related to molecular concentration.

Abstract: To provide a gas sensor chip, and a gas sensor provided therewith, capable of producing stable output characteristics over an extended period of time even when installed in a harsh environment such as a boiler smokestack carrying exhaust gasses. There is a backside structure wherein a catalyst carrier that contacts a gas to be measured is disposed on one side of a thermal conductor, a temperature sensing portion is disposed in a location that does not contact the gas to be measured, on the other side of the thermal conductor, and the temperature sensing portion measures the temperature corresponding to the temperature of the catalyst carrier through the thermal conductor, to enable the sensing of the amount of flow over an extended period of time without the temperature sensing portion being negatively affected by the gas to be measured.

Abstract: Systems, methods and computer program products for the multi-modal detection of particles are described herein. An embodiment of the present invention is a particle detector that includes a first chamber wherein analyte particles are subjected to a first particle detection mechanism, and a second chamber coupled to the first chamber, wherein the analyte particles are subjected to a second particle detection mechanism, and wherein the detection characteristics of second particle detection mechanism are orthogonal to detection characteristics of the first particle detection mechanism.

Abstract: A temperature measurement device includes a first thermocouple mounted on a tubular body that is shielded from the effects of radiation by a radiation shield, and a second, unshielded thermocouple. A difference in the measured temperatures from the first and second thermocouples is compared with calculated temperatures using an iterative process to determine a corrected temperature of the gas stream that estimates and compensates for incident radiation.

Abstract: A method and apparatus for improving accuracy of measurement of fluid pressure at a fluid port, such as at a supply port or control port of a fluid control valve, involves a closed-loop precision pressure measurement method with barometric pressure and temperature compensation.

Abstract: A method of analyzing a gas specimen mixture includes measuring the concentrations of inert components in the gas specimen mixture and the pressure and temperature of the gas specimen mixture. A number of sample gas mixtures are generated with varying percentages of hydrocarbon gases, each including the measured inert component concentrations. For each generated sample gas mixture, the method includes calculating the speed of sound therein based on the measured pressure and temperature and the particular percentages of hydrocarbon gases therein, measuring the speed of sound in the gas specimen mixture, and iteratively comparing the measured speed of sound with the calculated speed of sound in different sample gas mixtures until convergence for a particular sample gas mixture. The molecular weight of the particular sample gas mixture is calculated, and set the molecular weight of the gas specimen mixture to the calculated molecular weight.

Abstract: A gas specimen mixture analysis system includes at least one sensor for measuring the concentrations of inert components in the gas specimen mixture, a pressure sensor for measuring the pressure of the gas specimen mixture, and a temperature sensor for measuring the temperature of the gas specimen mixture. A subsystem measures the speed of sound in the gas specimen mixture, and a processing subsystem, responsive to the at least one inert component sensor, the pressure sensor, the temperature sensor, and the subsystem for measuring the speed of sound, is configured to generate a number of sample gas mixtures with varying percentages of hydrocarbon gases, each including the measured inert component concentrations.

Abstract: A heat switch for remote self-contained gas chromatography is disclosed. The device mechanically separates a hot or cold reservoir from the chromatography column when heating or cooling is not needed. The column needs a cooling system to obtain initial temperatures below ambient. At other times the column needs to be heated to relatively high temperatures, during which time the cooling system is preferably detached. The heat switch allows for rapid temperature changes while minimizing the peak cooling power requirement.

Abstract: A temperature sensor control apparatus includes a reference potential section, a driving potential section set to a driving electric potential, a temperature sensor configured to vary a resistance in accordance with a temperature, and disposed between the reference potential section and the driving potential section, a conduction path, two reference resistance elements each connected in series with the temperature sensor, a potential controlled point disposed in the conduction path between the reference resistance elements, a potential setting section configured to set an electric potential of the potential controlled point to the driving electric potential; and a resistance switching control section configured to control the potential setting section to switch the electric potential of the potential controlled point, and to switch each of the reference resistance elements to one of an energized state and a deenergized state.

Abstract: In a gas mixture temperature estimation method for an internal combustion engine, before a forefront portion of a gas mixture reaches an inner wall surface of the combustion chamber, the gas mixture temperature is calculated in accordance with a predetermined equation which is based on the assumption that no head exchange occurs between the gas mixture and cylinder interior gas which exists around the gas mixture without mixing with fuel. After the gas mixture forefront portion reaches the inner wall surface of the combustion chamber, the gas mixture temperature calculated in accordance with the equation is corrected in consideration of the quantity of heat transfer between the gas mixture and the cylinder interior gas and the quantity of heat transfer between the gas mixture and the wall.

Abstract: A micro fluid analyzer that may be highly sensitive, fast and very compact. The analyzer may use sufficiently low power per analysis to be easily implemented with an equivalently small battery pack or other portable power source. There may be energy conservation features in the analyzer, such as optimal adsorber film thicknesses in the pre-concentrator, concentrator and chromatographic separators. There may be special timing of the phased heating elements in the concentrators and separators to further reduce energy consumption. Various kinds of detectors and sensors may be incorporated in the analyzer for achieving low probability for false positives and detection versatility. There may be a controller that provides data acquisition and analyses, drive signals for control, management of wireless signal transmission and reception, processing, and other operational uses of the micro analyzer.

Abstract: A micromechanical thermal-conductivity sensor is provided which includes a thermally insulated diaphragm formed by a recess in a base plate exhibiting poor thermal conductivity. At least one heating element is applied on the diaphragm, at least one temperature-dependent electrical resistor is applied on the diaphragm for measuring the temperature of the diaphragm, as well as at least one further temperature-dependent electrical resistor is applied outside of the diaphragm on the base plate for measuring the ambient temperature. On one or both of its sides, the diaphragm is covered by a porous cover plate permitting gas exchange by diffusion, a cavity being left open between the diaphragm and the porous cover plate.

Abstract: Methods and systems for cooling gas chromatography ovens that comprise a housing having a fluid entry and a sleeve positioned within the housing to provide a fluid gap between the inner surface of the housing and the outer surface of the sleeve, where the sleeve is coupled to the fluid entry, and where a cooling fluid from the fluid entry traverses the inner layer of the sleeve and thereafter the outer layer of the sleeve via the fluid gap. In one embodiment, the housing includes at least one adjustable fluid exit, and the fluid gap is in fluid communications with the fluid exit(s). The fluid entry and the sleeve can be concentric, and the sleeve can include a heating element. A fan can be positioned to drive the cooling fluid from the fluid entry.

Abstract: A modeling module is disclosed that couples to a modular platform chassis. The modeling module includes a resident management controller to implement a test to model a component layout for a module to be received and coupled to the modular platform chassis. The test includes an operating thermal load for a component resident on the module at a given location. The module has a dimensional length and width that is similar to that of the modeling module. The modeling module also includes a thermal load device that is responsive to the management controller. The thermal load device is to implement at least a portion of the test by simulating the operating thermal load for the component resident on the module at the given location.

Abstract: An apparatus, method, and system for ensuring a more accurate and precise calibration of gas or liquid analyzers using gas emitting permeation tubes for the production of calibration samples. The permeation devices are placed in a temperature-controlled housing to ensure that calibration samples are produced at the optimal temperature for such devices. The housing temperature may be controlled by a semi-conductor heating and cooling device. The apparatus also controls the flow rate of the medium that is mixed with the impurities released from the permeation devices, yielding a more accurate, precise, and reliable calibration. The sample can be conveyed to the calibration device/instrument by hooking the apparatus directly to the calibration device. The invention also contemplates a novel method of calibrating apparatuses using a device kept at the optimal temperature, using a constant flow rate that minimizes variations in the calibrations.

Abstract: A precision gas flow meter that is capable of measuring small flow rates of gasses precisely in the range of 0.01 to 10 L per minute. The meter is designed to measure the gas flow in small volume increments of predetermined value, and therefore can be used to measure a gas flow that is continuous or discontinuous. The flow meter can be used to measure the gas production rates from many processes, including biological reactors, chemical reactors, and thermal-chemical reactors. The device can also be used to meter the gases that are required in small or minute volumes.

Abstract: A fluid analyzer having a concentrator and separator for concentrating and separating fluid samples at pressures up to about 10,000 psi (˜700 bar). The concentrator and separator may consist of a solid-state thin-film heater-adsorber and a channel supported by a solid substrate. The concentrator may have numerous heated interactive elements for adsorbing and desorbing constituents of a sample fluid. The interactive elements may be heated in a time phased sequential manner by heaters. The separator may separate the sample fluid by compound. There may be thermal conductivity detectors, a flow sensor and electrical conductivity detectors proximate to the channels. This system of concentrator, separator, heaters and sensor may provide information about the sample fluid composition. A pump may be connected to the channel to move the sample fluid through it.

Abstract: A micro fluid analyzer having a concentrator and separator. A strip continuous through a channel in the concentrator may provide a hot zone that may move with the flow of fluid through the channel of the concentrator to provide a concentration of heat in the flow. A pump may provide a flow to the fluid through the analyzer. Detectors may be positioned at places where the fluid may flow. A processor or controller may be connected to the strip, separator, pump and detectors. The concentrator, separator, detectors and processor may be integrated on one chip.

Abstract: An apparatus, system and method reduce the cool down time of GC ovens by supplying larger volumes of air through oven intake ducts. The system and method provide intake cross-sheets in an oven intake duct to reduce airflow spin, increasing the flow rate of fresh air into the GC oven and reducing the overall cool-down time of the GC oven. In addition, because the improved airflow allows the oven wall temperature to quickly match the oven air temperature, the noise in the temperature signal may be reduced. As a result, the GC oven can reach an equilibrium “ready” state faster. Furthermore, the utilization of the cross-sheets may allow for flexibility in the design of a fast GC oven—specifically in the location and shape of the intake duct—without loss of performance. This flexibility may become increasingly significant as GC ovens continue on the trend of becoming smaller and faster.

Abstract: The measuring sensor, particularly a lambda probe, has a ceramic sensor member retained at a high temperature during measuring operation. It is shielded from water droplets, carried along in the gas to be analyzed, by a heated protective housing, permeable for the gas to be analyzed, by which water droplets carried along in the direction of the sensor member are evaporated before reaching the sensor member. In this way, the water droplets are unable to cause any shock-like temperature drops at spots on the surface of the sensor member or material flaking.

Abstract: A carbon dioxide gas measurement and control system and method which comprises a thermal conductivity absolute humidity sensor which measures carbon dioxide during dynamic temperature and humidity changes by isolating the particular sensor response for absolute humidity and temperature, i.e., Vm(D,T) in order to track carbon dioxide concentration.

Abstract: A smoke sensor and a carbon monoxide sensor are integrated into a common detector housing. The smoke sensor is coupled to a smoke detector control integrated circuit which generates a binary output signal indicative of the presence of smoke. This signal is coupled to a programmed microprocessor in the detector housing. The carbon monoxide sensor is also coupled to the microprocessor. Outputs from the two sensors are processed substantially independently. In the presence of smoke, the smoke alarm is generated by the microprocessor. In the presence of sufficient levels of carbon monoxide, in the absence of smoke, a carbon monoxide alarm will be generated.

Abstract: The invention is a gas chromatograph that includes a mechanism to heat the carrier gas to a temperature higher than that of the columns through which it flows. The carrier gas may be temperature programmed to achieve much the same results as the known technique of temperature programming the column.

Abstract: A gas analyzer has a measuring chamber, a gas inlet channel, a gas outlet channel, a pump for providing a gas flow through the chamber, a device for irradiating the gas in the chamber with pulsating electromagnetic energy to generate acoustic pressure fluctuations therein, and at least one microphone communicating with the chamber for detecting the fluctuations. The inlet channel and the outlet channel each has an acoustic filter formed by channels with reduced sectional area of flow and a plurality of cavities associated therewith. The gas analyzer has at least one sandwich device formed of joined plate-like elements. The channel sections of the inlet and/or outlet channel are defined by at least two elements and the vibration-reducing cavities are also defined by at least two elements. The connections between the respective channels and cavities are formed as transverse apertures in the elements or element portions adjoining the channel and the cavities, respectively.

Abstract: A scaled quadrature pulse output signal is generated for representing direction and volume in predetermined increments of the flow of a liquid or a gas through a meter. An unscaled pulse signal is received from a meter. A scaling factor is applied to each unscaled pulse signal for accurately representing an increment of volume. The increments are sequentially added or subtracted to/from one another (depending upon flow direction) and a scaled quadrature output signal is provided for indicating the direction of flow and the volume of flow in predetermined increments.

Abstract: A gas chromatography system includes a gas chromatography oven having a door adapted for integration with gas chromatography modules which are located outside of the oven cavity. For these purposes, the oven door has module receiving openings in which the modules are secured. The gas chromatography module includes a module housing containing a main coil of the capillary column, a pair of transfer lines sleeved on the free ends of the capillary column, a heater wire wound on the transfer lines, and, optionally, a pair of chromatography connectors which extend into the oven cavity and through which the free ends of the capillary column, as well as transfer lines, projecting into the oven cavity. A wall of the GC oven has an injector port and a detector port for injection of a sample into the oven cavity and for detecting the sample constituents. Column lengths extend within the oven cavity between the module and injector and detector, respectively.

Abstract: The present invention includes electronic device workpieces, methods of semiconductor processing and methods of sensing temperature of an electronic device workpiece. In one aspect, the invention provides an electronic device workpiece including: a substrate having a surface; a temperature sensing device borne by the substrate; and an electrical interconnect formed upon the surface of the substrate, the electrical interconnect being electrically coupled with the temperature sensing device. In another aspect, a method of sensing temperature of an electronic device workpiece includes: providing an electronic device workpiece; supporting a temperature sensing device using the electronic device workpiece; providing an electrical interconnect upon a surface of the electronic device workpiece; electrically coupling the electrical interconnect with the temperature sensing device; and sensing temperature of the electronic device workpiece using the temperature sensing device.

Abstract: A method and apparatus using thermomechanical means for signalling the concentration of a reactive gas is disclosed. The thermomechanical means uses movement of a mechanical member to produce a signal corresponding to the concentration of the reactive gas in a gas stream. The method and apparatus may include means for converting a specific gas in a gas stream to a reactive gas. The apparatus may then provide an analog readout of the concentration of the specific gas.

Abstract: A smoke sensor and a carbon monoxide sensor are integrated into a common detector housing. The smoke sensor is coupled to a smoke detector control integrated circuit which generates a binary output signal indicative of the presence of smoke. This signal is coupled to a programmed microprocessor in the detector housing. The carbon monoxide sensor is also coupled to the microprocessor. Outputs from the two sensors are processed substantially independently. In the presence of smoke, the smoke alarm is generated by the microprocessor. In the presence of sufficient levels of carbon monoxide, in the absence of smoke, a carbon monoxide alarm will be generated.

Abstract: A system for determining the energy and volume delivered by a flowing natural gas carried within a pipeline based on BTU content analysis of the natural gas using a micro-miniature gas chromatograph. By monitoring key parameters of the flowing natural gas, such as temperature, pressure, flow rate, and BTU content, the system 110 accurately determines the total energy and total volume delivered by the flowing natural gas over a programmable duration of time. Micro-miniature fabrication of the gas chromatograph imparts important advantages to the system 110, including small size, modular design, low power consumption, fast BTU analysis times, and low consumption of consumable carrier and reference gases.