Abstract: A membrane filtration method and an apparatus for continuously monitoring the state of a membrane during the filtration, particularly for membrane fouling due to cake or gel layers of solutes developed on the surfaces of a filtered membrane, by estimating a membrane potential and a membrane solute rejection while making measurements of a set of physical properties of feed, variations of a streaming potential difference across pores of the membrane, variation in pressure differences between an upstream side and a downstream side of the membrane, and concentration differences between the feed and permeate filtered through the membrane.

Abstract: An improved structure of an electric connector of a gas sensor is provided which is designed to establish a firm electric connection between each electrode terminal formed on a sensing element and one of plural leads extending outside of the gas sensor for connection with an external device. The connector has a stopper which is placed in contact with an end wall of an insulating member to keep the connector on the insulating member without the connector dropping into a hole through which a lead extends from the sensing element when the lead is coupled to the connector. This allows the connector to be pressed and welded to secure the lead in a constant position relative to the insulating member, thus improving the stability of the sensor signal to be received at the external device.

Abstract: The invention relates to a probe device for determining the concentration of highly volatile components in liquids and/or gases, with a probe body (1) comprising a probe core (2) and a probe finger (3) being permeable for the highly volatile components, in the area of probe core (2) or of probe finger (3) a sensor (4) for the highly volatile components being provided, and comprising a protective tube (5) enclosing probe finger (3) and having passage openings (7). The invention teaches that protective tube (5) is configured as a piston (5) of a sluice device (6) having a measuring position and a servicing position of piston (5), and that passage openings (7) of piston (5) are disposed such that piston (5) has in addition the function of a slider valve sleeve, with probe finger (3) being connected over passage openings (7) in the measuring position to a measuring space (8) and in the servicing position to a servicing space (9) separated from measuring space (8).

Abstract: A gas sensor, comprises a substrate, a sensor unit including a functional layer and an electrode structure, and an electric heating and/or temperature measuring arrangement. An electrically conductive shielding structure is provided between the sensor unit and the electric heating arrangement in order to shield the measurement process at the sensor unit from interferences owing to the heating process, thereby reducing or preventing the effects of electrical fields caused by voltages applied to the heating arrangement from altering or disrupting the measurement process.

Abstract: Method and apparatus are provided for a non-invasive bubble measuring instrument operable for detecting, distinguishing, and counting gaseous embolisms such as bubbles over a selectable range of bubble sizes of interest. A selected measurement volume in which bubbles may be detected is insonified by two distinct frequencies from a pump transducer and an image transducer, respectively. The image transducer frequency is much higher than the pump transducer frequency. The relatively low-frequency pump signal is used to excite bubbles to resonate at a frequency related to their diameter. The image transducer is operated in a pulse-echo mode at a controllable repetition rate that transmits bursts of high-frequency ultrasonic signal to the measurement volume in which bubbles may be detected and then receives the echo. From the echo or received signal, a beat signal related to the repetition rate may be extracted and used to indicate the presence or absence of a resonant bubble.

Abstract: A device which may be carried by and part of an unmanned vehicle which measures characteristics of manure of animals such as dairy cows that are milked and fed in a stable provided for them. The vehicle is supported by three driven wheels and carries a mechanism for analyzing manure which comprises a compression chamber for receiving a manure sample. A sieve is provided on one side of the chamber and a piston forces the manure sample through the sieve. By measuring the pressure required to squeeze the manure sample through the sieve, characteristics such as the fibrousness and the viscosity of the manure sample can be determined. The vehicle also carries an identification instrumentality for identifying the animal that provided the manure sample and may carry a temperature sensor and an inertia meter. It is operatively associated with a computer which registers data provided from analysis of each animal's manure sample and provides same as displayable data.

Abstract: The liquid to be measured flows through a flow-pipe and bathes the end (1) of a pivoting probe in a spectrophotometric cell (2). One measuring surface (15) of the probe (2) remains immersed in the liquid whose level is advantageously assured by an overflow barrier (19); but when the probe has pivoted, the measuring surface opens onto a duct (23) in which a rinsing liquid flows and leads into the flow-pipe and cleans it. This rinsing is quick and safe and requires no dismounting of the probe. The invention applies in particular to liquids containing radioactive products such as uranium and/or plutonium.

Abstract: Method and apparatus are provided for a non-invasive bubble measuring instrument operable for detecting, distinguishing, and counting gaseous embolisms such as bubbles over a selectable range of bubble sizes of interest. A selected measurement volume in which bubbles may be detected is insonified by two distinct frequencies from a pump transducer and an image transducer, respectively. The image transducer frequency is much higher than the pump transducer frequency. The relatively low-frequency pump signal is used to excite bubbles to resonate at a frequency related to their diameter. The image transducer is operated in a pulse-echo mode at a controllable repetition rate that transmits bursts of high-frequency ultrasonic signal to the measurement volume in which bubbles may be detected and then receives the echo. From the echo or received signal, a beat signal related to the repetition rate may be extracted and used to indicate the presence or absence of a resonant bubble.

Abstract: A method and apparatus for retrieving magnetic casing fragments from a well using a shrouded magnet are disclosed. Retrieving casing fragments allows the determination of weight loss from the casing to assist in analyzing the integrity and the condition of the casing and to determine whether more expensive analysis is required. The shrouded magnet, that is formed by a non-magnetic container enclosing a source of magnetic field, recovers metal casing fragments by attracting them and other magnetic materials from oil and gas well fluids passing by the shrouded magnet device, which fragments are easily separated from the device by removing the source of magnetic field from the container.

Abstract: System of evaluating physical parameters such as the absolute permeability of porous rocks of a zone of an underground reservoir, from fragments taken from this zone, such as rock cuttings carried along by the drilling mud. Rock fragments (F) are immersed in a viscous fluid contained in a vessel (1). Pumping means (2, 3) first inject into vessel (1) a fluid under a pressure that increases with time, up to a determined pressure threshold, so as to compress the gas trapped in the pores of the rock. This injection stage is followed by a relaxation stage with injection stop. The pressure variation measured by detectors (7, 8) during these two successive stages is recorded by a computer (9). The evolution of the pressure during the injection process being modelled from initial values selected for the physical parameters of the fragments, the computer adjusts them iteratively so as to best get the modelled pressure curve to coincide with the pressure curve really measured. Application: petrophysical measurement.

Abstract: A robust single-chip hydrogen sensor and a method for fabricating such a sensor. By adding an adhesion-promoting layer between the body of a sensor and an on-chip hydrogen-exposed electrically-resistive hydrogen-sensing element, device yields are improved when compared to directly applying the electrically-resistive hydrogen-sensing elements to the sensor body. The resistance of the sensing element is indicative of the hydrogen in the medium surrounding the sensor. According to a preferred embodiment of the present invention, the adhesion-promoting layer is a chromium (Cr) adhesion layer, and the hydrogen-exposed electrically resistive hydrogen sensing element is a PdNi alloy.

Abstract: Device and method for determining a wheel braking pressure and/or an admission pressure in a braking system in which pressure medium is introduced from a reservoir for the pressure medium having an admission pressure into a wheel brake through at least one shutoff device for inlet and/or outlet and/or passage of a pressure medium, it being possible to remove pressure medium from the wheel brake through at least one means delivering the pressure medium. In so doing, a pressure quantity representing the admission pressure is estimated, at least one operating state of at least one actuator in the braking system is detected and the wheel braking pressure is estimated as a function of the estimated admission pressure and the detected operating states.

Abstract: For tightness testers with a plurality of in-line test stations (1) on a conveyor it is proposed to supply the tightness-relevant measurement signals from the chambers by detecting pressure change measurements via pressure sensors or electrical impedance measurements via electrodes that occur at the test stations over a time interval. The signals are supplied through multiplexers (5) to a central evaluation (9).

Abstract: An assembly for desorbing sampling tubes comprises a gas chromatograph known per se provided with an injector. The sampling tubes are provided with an inflow opening and an outflow opening. The assembly comprises an adapter which is placed in the injector and which is provided with a chamber which is bounded by a heat conducting housing. The adapter is arranged for placing a sampling tube in the chamber thereof, while in a condition of a sampling tube wherein it is placed in the adapter, the inflow opening thereof is in fluid communication with a first carrier gas supply duct, while the outflow opening of the sampling tube is in fluid communication via the injector with a gas chromatography column disposed in the gas chromatograph.

Abstract: A system and method for determining a time of occurrence of a pressure wave in a pipe provides a first sonic transducer and a second sonic transducer at each of a plurality of site locations along a pipe. Sonic waves are generated through a pipewall at a known desired rate. At each of the plurality of site locations, the sonic waves travel from the first sonic transducer to the second sonic transducer through a liquid flow in the pipe. A measure of travel time is set for the sonic waves. The measure is compared to each of the successive travel times for the sonic waves as the sonic waves arrive at the respective second transducers. A string of counts is output at each second transducer. Each count includes a first count value if a present sonic wave has a travel time that is late as compared to the measure. A time of occurrence of the pressure wave is determined based on a reference clock when the string of counts includes a string of first count values longer than a threshold value.

Abstract: A gas concentration measuring apparatus is provided which measures the concentration of two kinds of gas components such as O2 and NOx contained in exhaust gasses of an internal combustion engine of automotive vehicles. The apparatus has a gas sensor which includes a first cell responsive to application of a voltage to discharge O2 in the exhaust gasses to the outside and produce an electric current as a function of concentration of the discharged O2 and a second cell responsive to application of a voltage to produce an electric current as a function of concentration of NOx in the exhaust gasses from which the O2 is discharged by the first cell. The apparatus offsets an error component of the electric current produced by the second cell which depends upon O2 contained in the exhaust gasses.

Abstract: For leak testing closed containers (9) which are filled with a filling product containing at least one liquid component the container is introduced in a test cavity (1) which is evacuated at least down to vapour pressure of that liquid component. The pressure in the surrounding of the container (9) and thus within test cavity (1) is monitored. Monitoring is performed by a vacuum pressure sensor (7), whereas lowering pressure surrounding the container (9) is performed by a vacuum pump (5). Leakage is detected by monitoring a pressure change in the surrounding of the container which is due to evaporation of liquid emerging from a leak and being evaporated in the low pressure surrounding.

Abstract: An acoustic viscometer and method for determining both the kinematic viscosity and the intrinsic viscosity of a liquid which includes an acoustic wave generator, a transmitting piezoelectric transducer, a receiving piezoelectric transducer, and a phase-shift detector. The transmitting piezoelectric transducer is positioned so as to be in contact with the liquid and is operably connected to the acoustic wave generator. The transmitting piezoelectric transducer propagates a longitudinal wave of known frequency through the liquid. The receiving piezoelectric transducer is spaced apart from the transmitting piezoelectric transducer and detects the longitudinal wave and a corresponding shear wave propagated through the liquid.

Abstract: A method and equipment for measuring vapor flux from a surface e.g. the rate of water loss from human skin which is useful in the evaluation of the efficiency of the skin/water barrier uses a closed cylinder which is placed with the open end against the skin and the closed end is cooled. By measuring the temperature and relative humidity within the cylinder the water vapor flux can be determined.

Abstract: The mass of particulate of an effluent gas flowing in a stack is measured with a mass measurement assembly in which sampling is isokinetically controlled by determining in real-time the molecular weight of the effluent gas, and in particular, determining the moisture content of water vapor in the effluent gas. Readings from a pair of flow sensors connected in series and separated by a dryer are compared to provide a real-time moisture measurement of the effluent gas. The moisture measurement is used to determine a total molecular weight of the effluent gas in real-time and the velocity of the effluent gas in real-time for isokinetic sampling during measurement of the mass of particulate flowing in the effluent gas.