Abstract: A self-contained, transportable system for conducting any of hydrologic tests or water sampling techniques without the need for retooling or readjusting the system. The system includes a borehole unit for conducting the tests in a borehole, and a data acquisition unit for monitoring and recording the results of the tests. The borehole unit includes, connected in serial relation, a pair of borehole packers for forcing the unit in place in the borehole, several pressure transducers for obtaining hydraulic measurements, a pump located between the borehole packers for withdrawing fluid and a fluid injector for injecting fluid. The data-acquisition system includes flow meters for monitoring fluid injection and fluid withdrawals, a data-acquisition module for monitoring a fluid pressure from the pressure transducers, power source and a computer interface.

Abstract: An apparatus and method for determining the viscosity of the circulating blood of a living being over plural shear rates caused by a decreasing pressure differential by monitoring the changing weight of the blood, or the changing level of a column of blood over time. The apparatus and method utilize a riser, a capillary tube, a collector and a mass detector, such as a precision balance or a load cell, for monitoring the changing weight of a sample of fluid that flows through these components under the influence of the decreasing pressure differential; alternatively, the apparatus and method use a column level detector to monitor the changing level of the column of blood over time.

Abstract: The present invention herein relates to a sample injection device for micro gas chromatograph is assembled from five layers of thin plates and membrane. The first layer serves as cover plate and interfacial connection to outside columns. The second layer is fabricated with a sample channel and a carrier gas inlet split into an analytical channel and a reference gas channel, and two valve seats. The third layer is a flexible diaphragm for valve actuation. The fourth layer is fabricated with a pressurizing gas inlet hole and pressurizing channel leading to the diaphragms of valve seats. The fifth layer serves as another cover plate. An external solenoid valve is used to control the processes of sampling and injection. The channels and valve seats on each layer plate can be fabricated through several well-developed fabrication techniques such as photolithographic, LIGA processes or precision micro machining. All five layers are properly aligned and bonded by adhesives.

Abstract: A device for determining the adequacy of a sealant between construction elements is attached to a source of compressed air whose pressure is controlled by a regulator. The device includes a cylinder containing at least one piston, the piston containing an air chamber and a plunger, the air chamber being in communication with a pressure gauge. The device also includes an armature having a first and a second end, the first end being attached to the cylinder, the second end having a flow valve and an air fitting in communication with the air source, the handle containing tubing as a means to conduct air from the compressed air source, the tubing being interrupted with a bleed valve. The device also includes a moveable tip such that the tip moves in the direction parallel to the axis of the cylinder, said tip comprising a wheel, a wheel bracket and a plunger shaft, the plunger shaft being attached to the plunger within the piston.

Abstract: Gas chromatographs of the invention generally comprise four or more analysis channels. Specifically, four or more gas chromatography columns are configured for parallel analysis of four or more gaseous samples with detection being effected using a microdetector array comprising four or more microdetectors. In one embodiment, the four or more microdetectors 510 are microfabricated detectors, and are integrally formed with a substrate or with one or more microchip bodies mounted on a substrate. In a preferred embodiment, a microdetector array comprises four or more thermal conductivity detectors having one or more thin-film detection filaments. A preferred heated environment for highly parallel gas chromatographs is also disclosed.

Abstract: A monitoring system for chemical shipments having an apparatus for detection of a leak from a shipment vessel having a shroud. A first chemical sensor is in communication with a chamber of the shroud for detecting the presence of a substance leaking from the vessel. A second sensor is in communication with the ambient environment surrounding the shroud. A monitoring circuit in communication with the first chemical sensor and the second chemical sensor monitors a first chemical sensor output and a second chemical sensor output and signals an information unit dependant on the increase of at least one of the first and second chemical sensors. The information unit emits a signal to an alarm or output device in response to an increase of the magnitude and/or rate of increase of at least one of the first chemical sensor output and the second chemical sensor output. A physical sensor can be in combination with the monitoring circuit.

Abstract: The invention relates to a gas analyzer comprising a measuring volume (6) for a sample gas mixture (G), a radiation source (1) for providing a beam (20) of electromagnetic radiation to pass said measuring volume, a heat sink (4) for said radiation source, at least one thermopile detector (9), at least one optical bandpass filter (10), electrical contact pins (12) for signal(s) in the housing of said detector, a thermal mass formed of a material having high thermal conductance. Said thermal mass has a cavity (21) and an outer surface (22), surrounding at least said detector housing in the cavity, being in contact with said detector housing, and extending towards the radiation source. There is a thermal barrier between the heat sink (4) and the thermal mass (8, 16). The gas analyzer further comprises electrical wires (15), which are composed of materials and having dimensions producing an overall thermal conductance substantially lower than that of said electrical contact pins.

Abstract: In a method and apparatus for monitoring the composition of a breathing gas mixture having a first gaseous component and a second gaseous component, a data processor is supplied, either as an input value or as a measured value from associated humidity sensors with an indication of a moisture content value (RHComp1) for the first gaseous component and a moisture content value (RHComp2) second gaseous component before mixing. An indication of the moisture content value for the mixture (RHMix) is measured and provided to the data processor. From these inputs the data processor determines a value indicative of the amount (x,y) of one or both of the first gaseous component and the second gaseous component in the mixture according to the relationship: RHComp1·x+RHComp2·y=RHMix.

Abstract: Microfluidic devices, systems, and methods measure viscosity, flow times, and/or other flow characteristics within the channels, and the measured flow characteristics can be used to generate a desired flow. Multi-reservoir pressure modulator and pressure controller systems, electrokinetic systems and/or other fluid transport mechanisms can generate the flow, controllably mix fluids, and the like.

Abstract: A gas detector, as useful for conducting refrigerant fluid leak detection, having a housing, a probe and a sample flow path assembly capable of providing a sample air flow rate to a sensing device in excess of 300 SCCM. The sample flow path assembly also provides the gas detector with a short signal path between the sensing device and a printed circuit board within the housing, an efficient sample path, and ready access to and easy replacement of the sensing device as well as of the probe, making the gas detector generally more reliable and cost effective. The sample path assembly requires a simple method of construction and sensing device replacement thereby reducing the difficulty and the time required for manufacturing the sample flow path assembly and, ultimately, reducing the cost of manufacturing the electronic gas leak detector.

Abstract: 1. Method for testing the tightness of capacitive sensors 2.1. Known methods of seal testing cannot be used because of the extremely small volume of the sensor cavity or on wafer level. Other known methods of seal testing are only possible with high expenditure on safety because, for example, radio isotopes are used. 2.2. Method for testing the tightness of capacitive sensors arranged in a hermetically sealed enclosure, in which the processed sensors are arranged in the form of a wafer, wherein the already sawn wafer bearing the sensors is immersed in a test fluid under defined conditions, the capacitance of each sensor is then measured and compared with the capacitance of reference sensors. 2.3. The invention is especially suitable for testing the tightness of capacitive, hermetically sealed sensors.

Abstract: A hand-held chemical vapor detector for detecting biological substances in an indoor and outdoor setting is claimed. More specifically, the present invention relates to a plasma chromatograph (PC) vapor detector that is interfaced to a biological sample processing and transfer introduction system. The biological sample processing was accomplished by quartz tube thermal decomposition (TD), and the resultant vapor was transferred by gas chromatography (GC) to the PC detector. This system is comprised of a thermal decomposition module, gas chromatography module and a plasma chromatograph detector. These components are connected in a series fashion. The device is referred to as a Biological Classifier System (BCS). The BCS can be described as a hyphenated device where two analytical dimensions (the GC and PC), in series, allow the separation and isolation of individual components from the thermal decomposition of biological analytes.

Abstract: A method for measuring viscosity of liquid, in which a liquid detecting piece 3 is vibrated by a vibrator 1, vibration of the liquid detecting piece 3 in liquid 4 is detected, and viscosity of the liquid 4 is measured from vibration thus obtained, the method comprising the steps of detecting frequency and amplitude which are variable attributable to liquid-specific visco-elasticity from the vibration, obtaining impedance of the liquid from the frequency and the amplitude, and obtaining a dynamic viscosity from a real number part and an imaginary number part of the impedance. There is also disclosed a method for measuring visco-elasticity of liquid comprising the step of obtaining a dynamic viscosity, a dynamic elasticity and a static elasticity of the liquid from a real number part and an imaginary number part of the impedance.

Abstract: A method and sensor or sensor subsystem permit improved evaporative leak detection in an automotive fuel system. The sensor or sensor subsystem computes temperature-compensated pressure values, thereby eliminating or reducing false positive or other adverse results triggered by temperature changes in the fuel tank. The temperature-compensated pressure measurement is then available for drawing an inference regarding the existence of a leak with reduced or eliminated false detection arising as a result of temperature fluctuations.

Abstract: A system for conducting high-temperature liquid chromatographic analysis includes a mobile phase transport tube configured to operably convey mobile phase from a source to respective chromatographic instruments in the system, a pre-heater apparatus operably coupled to the mobile phase transport tube for heating the mobile phase to a desired temperature, a chromatographic column operably coupled to the pre-heater apparatus, and including temperature-maintaining means for maintaining the column at a pre-determined temperature and a counter-flow heat exchanger operably exchanging heat from outlet mobile phase to inlet mobile phase through conductive heat transfer means. In a particular embodiment, the mobile phase passing through the chromatographic column is maintained in a substantially adiabatic environment.

Abstract: A method for locating an internal transfer leak in a fuel cell stack by applying a substantially constant gas pressure difference between a first fluid stream passage and a second fluid stream passage, wherein gas pressure in the second fluid stream passage is higher than gas pressure in the first fluid stream passage. A test gas is supplied to the second fluid stream passage and a test liquid is supplied to the first fluid stream passage. A parameter indicative of flow rate of the test gas exiting the first fluid stream passage is measured as the test liquid fills the first fluid stream passage. An apparatus for locating an internal transfer leak in a fuel cell stack is also provided.

Abstract: Described is a method of measuring the permeability of a coating (3) on a plastic wall (1) to low-molecular gases, wherein the diffusion coefficient and/or solubility coefficient of the coating (3) with respect to the low-molecular gases is an order of magnitude lower than that of the plastic wall (1), wherein the space (4) on the coating side is subjected to the action of a first fluid (5) and is flushed through therewith until only said first fluid (5) is in the space. Also described is a device for carrying out the method.

Abstract: A method for automatically conducting a leak test for a vacuum system includes receiving a process status input representing the completion of a manufacturing cycle. On determining that the process status is in a complete state, the vacuum system isolation valve is closed. In one embodiment, the first pressure input is measured at the beginning of the leak test and compared to a second pressure input measured at the expiration of timer. If the difference between the first and second pressure measurements are greater than the configurable threshold pressure, then the vacuum system is determined to be leaky. In another embodiment, the vacuum system is determined to be leaky if at least one of a series of pressure measurements exceeds the threshold pressure value. In response to the determination of the leak, an interlock signal to disable the operation of the vacuum system is activated.

Abstract: A hydraulic leakage rate testing device for testing hydraulic components has two circuits, a filling circuit that fast-fills the component with hydraulic fluid and a leakage circuit that measures the leakage rate of fluid flow through the component. The filling circuit is first connected to the component to fill the component. Once full, flow through the filling circuit is blocked and flow to the component is provided by the leakage circuit, which includes a leakage flow rate measuring device. The filling circuit provides a flow rate that is at least twice the flow rate provided through the leakage circuit.

Abstract: A sensor probe and method of use for determining the temperature, velocity, and/or liquid volumetric fraction of gas laden with droplets. In one variation, the probe includes a single heating element used in a well-characterized flow. The heating element is maintained above the Leidenfrost transition for the droplets, which prevents cooling effects from the droplets from impacting the temperature measurement. In another variation, the probe includes two or more heating elements arranged in similar flow environments. The property of interest is derived by relying on thermodynamic and heat transfer principles, which are not usable in conjunction with conventional devices.