Abstract: Systems and methods for positive dispense verification. In one aspect, a system has a plurality of light emitters. The light from the emitters is directed toward a plurality of light detectors across a proximately horizontal plane. The liquid dispense device is positioned above the horizontal plane of light emission from the plurality of light emitters to the plurality of light detectors such that the dispensed liquid will travel through the horizontal plane defined by the emitted light and onto the container being inoculated. Each of the plurality of detectors is coupled to an amplifier. The amplifier generates a signal in response to an interrupt in the transmission of light from the light emitters to the light detectors when the light path is disrupted by the dispense of liquid confirming the liquid was dispensed onto the container.

Abstract: A sample analyzer with an optical detection device and a sample analysis method of the sample analyzer are disclosed. The optical detection device includes a fluid chamber, a light source and a light detector. The fluid chamber includes an illumination zone. An analyte flows through the illumination zone so as to form a sample stream. The light source illuminates the illumination zone to excite cell articles, reacted with a reagent, of the sample stream to emit a light signal. The light detector detects the fluorescent lights and transforms it into an electric signal. The light detector can include a silicon photomultiplier.

Abstract: An automated analyzer includes an analysis operation part that causes a sample and a reagent to react and based on the reaction result performs analysis of the sample, wherein: the automated analyzer includes a plurality of units constituting the analysis operation part, a temperature adjustment mechanism that heats or cools the units, a temperature sensor that measures the temperature of the units, and a control part that controls the temperature adjustment mechanism. The control part sets the measurement startable temperature range of each unit, which is the temperature range of the operation specification thereof, and the operable temperature range, which is a temperature range that is wider than the measurement startable temperature range, and starts the analysis process of the sample when the temperature of each unit has entered the operable temperature range.

Abstract: Embodiments of the present disclosure provide optical methods and systems to evaluate the performance of a demulsifying agent in wellbore fluid. The present embodiments provide an optical system which scans wellbore fluid in order to detect the phase separation caused by a demulsifying agent. Using spectral data, the optical system quantifies the opacity and/or transparency of the different phases in the wellbore fluid in order to evaluate the demulsifying agent.

Abstract: A drip chamber for an infusion tube that includes a first end arranged to receive a drip tube, a second end including an exit port, at least one wall connecting the first and second ends, a space enclosed by the first and second ends and the at least one wall, and first and second lenses each directly fixed to said at least one wall.

Abstract: A fluid measurement apparatus according to an embodiment includes an optical emitter capable of radiating light to an irradiation target including a fluid, an optical detector capable of receiving scattered light scattered by the fluid, and a controller that includes a generator configured to generate a frequency spectrum based on the scattered light and an estimation unit configured to estimate a flow state of the fluid, based on a characteristic component of the frequency spectrum. The controller causes the generator to generate a first frequency spectrum based on a measurement target fluid and a second frequency spectrum based on the fluid in a known flow state, and then causes the estimation unit to compare a characteristic component of the first spectrum and a characteristic component of the second frequency spectrum, whereby the controller can estimate a flow state of the measurement target fluid.

Abstract: Systems and methods for increasing the accuracy of a turbidity sensor are disclosed. The systems include a turbidity sensor and a flow module with a specialized flow path, with the turbidity sensor engaging with the flow module such that a measurement zone of the turbidity sensor is disposed within a flow path of the flow module and a bypass path of the flow module does not pass through the measurement zone. The methods include flowing a fluid containing bubbles into a system that separates the fluid in the flow module into a first stream of fluid containing relatively more bubbles and a second stream of fluid containing relatively fewer bubbles, the first stream flowing through a bypass path that does not pass through the measurement zone, and the second stream flowing through the measurement zone of the turbidity sensor.

Abstract: Techniques for optical analysis of fluid samples using sensors and water enhancing agents for in-line measurements with a continuous flow of the fluid samples are provided. In one aspect, a device includes: at least one reagent dispenser located at an introduction point along a conduit, the conduit being configured to contain a flow of a fluid sample; at least one first detector located at a first detection point along the conduit downstream from the introduction point; and at least one second detector located at a second detection point along the conduit downstream from the first detection point, wherein the at least one first detector and the at least one second detector are configured to make optical measurements of the fluid sample. A method employing the device is also provided.

Abstract: Microscatterometry system for generating an angularly resolved scattered light profile from the collected data.

Abstract: In the additive manufacturing process, a monitored or controlled mixture of materials is deposited to form an additive manufactured product by delivering the mixture of materials through a material flow path while using an excitation source to introduce electromagnetic energy into the material flow path using a circuit element having inductive or capacitive reactance disposed adjacent the material ejecting orifice. The excitation source produces an electromagnetic field condition within the material flow path that is responsive to at least one of the permeability and permittivity properties of a space within the material flow path. A sensing means coupled electrically or magnetically to the excitation means is responsive to the electromagnetic field condition and provides at least one control parameter based on the electromagnetic field condition that may be used to control the composition of the mixture of materials by adjusting proportions of constituent materials.

Abstract: A method for detecting and counting particles suspended in fluids, such as bacteria suspended in urine, utilizing dynamic features of the suspended particles and employing light scattering measurements. The disclosed method is suitable for determining the susceptibility of bacteria to antibiotics. A cuvette for detecting bacteria in fluids, which is especially suited for the light scattering measurements, is provided.

Abstract: A method of illuminating and extracting scattered and transmitted light from a liquid within a sealed glass bottle, the method comprising initiating transmission of an incident light beam from a light source to the sealed bottle, directing the incident light beam to totally internally refract within a wall of the sealed bottle and thereby cause an evanescent wave within the liquid to generate scattered or absorbed light, receiving the scattered or absorbed light from the liquid contained in the sealed bottle, and processing one or more signals representative of the scattered or absorbed light, the signals indicative of one or more molecules indicative of a characteristic being present in the liquid contained in the sealed bottle.

Abstract: A covered chamberless particulate detector includes a chamberless detector configured to produce a signal when particulate sensing events occur; one or more optical emitters disposed on the chamberless detector, configured to emit one or more emitting cones of light; one or more optical sensors disposed on the chamberless detector, defining one or more receiving cones; and a protective cover on the chamberless detector defining an inside region and an outside region. Each of the one or more optical sensors is configured to detect occurrence of particulate sensing events. The protective cover includes a material having one or more optical properties of transmission, reflection, and absorption; and at least of these optical properties has a bandwidth.

Abstract: Systems and methods for increasing the accuracy of a turbidity sensor are disclosed. The systems include a turbidity sensor and a flow module with a specialized flow path, with the turbidity sensor engaging with the flow module such that a measurement zone of the turbidity sensor is disposed within a flow path of the flow module and a bypass path of the flow module does not pass through the measurement zone. The methods include flowing a fluid containing bubbles into a system that separates the fluid in the flow module into a first stream of fluid containing relatively more bubbles and a second stream of fluid containing relatively fewer bubbles, the first stream flowing through a bypass path that does not pass through the measurement zone, and the second stream flowing through the measurement zone of the turbidity sensor.

Abstract: Various devices, systems, and methods may be presented. A sensor unit may be presented that includes a housing and a chamber arranged within the housing and configured to receive air from outside of the housing of the sensor unit. Also present may be a sensor arranged within the housing and configured to measure a characteristic within the chamber. The sensor unit may include a fan arranged within the housing in relation to the chamber, the fan configured to clear air from the chamber of the sensor unit. Further, the sensor unit may include a controller in communication with the fan and the sensor, the controller configured to operate the fan.

Abstract: The present disclosure provides an instrument and methods for detecting an analyte, comprising a light source capable of generating excitation light for exciting a plurality of luminescence labels, an excitation beam path extending between said light source and said analyte, a detector capable of detecting light emitted from said luminescence label, an emission beam path extending between said analyte and said detector, a filter carrier carrying two or more pairs of filter portions, each pair being related to one luminescence label and comprising a first filter portion for transmitting excitation light and a second filter portion for transmitting emitted light, wherein said first filter portion of one pair is said second filter portion of another pair, and wherein said filter portions are arranged in a manner that a respective one of said pairs can be brought in an operative condition in which said first filter portion is in said excitation beam path and said second filter portion is in said emission beam pat

Abstract: Systems and methods to measure fluid delivery times in a piping system and more particularly a dry pipe fire protection system. A device is provided that includes at least a solenoid valve for coupling to a network of pipes of a dry pipe sprinkler system and a liquid detector for coupling to the network of pipes to detect a flow of water in the network. A timer is coupled to the solenoid valve. Upon operation of the solenoid valve, the timer simultaneously initiates a start time of a fluid detection test. The timer is preferably coupled to the liquid detector such that upon the detector detecting water, the timer defines a stop time of the fluid detection test.

Abstract: A sensing system according to the embodiment of the present invention includes an optical actuator configured to apply an optical stimulus into a detection target substance, a photo detector configured to output an electrical signal having a snapback form in response to an optical response generated according to a concentration of the detection target substance to which the optical stimulus is applied, an amplifier configured to amplify the electrical signal output from the photo detector and to provide the amplified electrical signal as positive feedback to the optical actuator, and a detection unit configured to detect the detection target substance in response to the electrical signal.

Abstract: A chemical controller for an aquatic application comprising at least one output relay. The chemical controller further includes a current detection circuit configured to detect current on an output of the at least one output relay and a current fault detection device configured to output a current fault signal indicative of the occurrence of a current fault condition. The chemical controller further comprises at least one relay latch configured to receive the relay enable signal and the current fault signal and to decouple the relay enable signal from a corresponding relay latch output when the current fault signal indicates the occurrence of a current fault condition. A relay drive circuit is configured to receive a signal from the corresponding relay latch output to and to responsively activate and deactivate the at least one output relay.

Abstract: There is provided a light control circuit including a detected voltage generating circuit, a reference voltage generating circuit, an error amplifier, an NMOS driver and a light source. The detected voltage generating circuit outputs a detected voltage to a first input terminal of the error amplifier. The reference voltage generating circuit outputs a reference voltage to a second input terminal of the error amplifier. The NMOS driver changes a drive current of the light source according to an output of the error amplifier.

Abstract: An air-to-air background-oriented Schlieren system and method for measuring and rendering visible density changes in air that cause a refractive index change by an airborne vehicle. A sensor aircraft equipped with a high-speed visible spectrum camera travels at low airspeed on a predetermined route and on a level altitude over a background having consistent contrast and sunlight reflectivity. The target aircraft, traveling on the same predetermined route but at an altitude between the sensor aircraft and the ground (background) passes beneath the sensor aircraft. The camera on the sensor aircraft captures a series of images including a reference image immediately before the target aircraft enters the image frame followed by several data images as the target aircraft passes through the image frame. The data images are processed to calculate density gradients around the target aircraft. These density gradients include shockwaves, vortices, engine exhaust, and wakes.

Abstract: A photoelectric smoke sensor includes a housing having a circuit accommodation chamber, an inflow chamber provided in the housing, a light emitting portion provided in the inflow chamber, and a light receiving portion provided in the inflow chamber. The light emitting portion includes a first light and a first support portion surrounding the first light guide. The light receiving portion includes a second light guide and guiding the light to the light receiving element and a second support portion surrounding the second light guide. The first support portion and the second support portion are configured to prevent escape of a flame from the circuit accommodation chamber to the inflow chamber.

Abstract: A method for distinguishing between an alarm condition and a nuisance condition in a smoke detector. The smoke detector comprises an illuminator and a light sensor. The method includes measuring a voltage signal in response to an electromagnetic signal emitted by the illuminator, and comparing the voltage signal to an alarm threshold. A rate of change of the voltage signal is determined in response to the comparison of the voltage signal and the alarm threshold. A first frequency component of a first portion of the voltage signal and a second frequency component of a second portion of the voltage signal is determined. The first frequency component and the second frequency component are compared to distinguish between the alarm condition and the nuisance condition. An indication of the alarm condition and the nuisance condition is respectively generated upon an identification of the alarm condition and the nuisance condition.

Abstract: A device for analysis and monitoring of toxicity in waters is described. The device is specifically devised for determining toxicity in waters in several samples at the same time and in quick time with a high degree of accuracy and precision. The device has application in the field of controlling and monitoring the water resources and in the field of the ecotoxicological analyses.

Abstract: A particle fractionating apparatus is described that can sort droplets containing particles in a first mode of operation, and distribute droplets that do not contain particles to a plurality of locations in a second mode of operation. The modes of operation are selectable by a user. Droplets may be emitted from a microchip of the particle fractionating apparatus.

Abstract: A smoke and/or fire detector for the detection and distance measurement of smoke (36) in a monitored zone (2), having a light transmitter (4) for transmitting a transmitted light signal (8), having a light receiver (6) for generating a received light signal (10) from the transmitted light signal (8) remitted or reflected in the monitored zone (2), and having an evaluation unit (12) for evaluating the time of flight of the received light signal (10), wherein the evaluation unit (12) has a transient recorder (14) and wherein the transient recorder (4) is configured to record multiple received light signals (10) of a single transmitted light signal (8) successively following in time in a time period and the evaluation unit (12) is configured to evaluate the received slight signals (10).

Abstract: A microfabricated sheath flow structure for producing a sheath flow includes a primary sheath flow channel for conveying a sheath fluid, a sample inlet for injecting a sample into the sheath fluid in the primary sheath flow channel, a primary focusing region for focusing the sample within the sheath fluid and a secondary focusing region for providing additional focusing of the sample within the sheath fluid. The secondary focusing region may be formed by a flow channel intersecting the primary sheath flow channel to inject additional sheath fluid into the primary sheath flow channel from a selected direction. A sheath flow system may comprise a plurality of sheath flow structures operating in parallel on a microfluidic chip.

Abstract: A detection apparatus includes four sets of transmitter and receiver wherein the transmitters are on a first sliding member of a frame and the receivers are on a second sliding member of the frame; and drives for moving the first and second sliding members back and forth. During the movements of the first and second sliding members, each transmitter emits laser beam toward the receiver of the same set by passing through a space above a photoresist-coated optical glass by 100 ?m, no signal is generated at the receiver if the laser beam is not blocked, and a signal is generated at the receiver if the laser beam is blocked by at least one of a plurality of particles on the photoresist-coated optical glass.

Abstract: Apparatus and methods for size-specific detection of particles entrained in fluids are provided. A particle size selector separates particles entrained in a sample fluid stream using a curved channel. Shroud fluid streams are interposed between the sample fluid stream and walls of the channel. Centrifugal forces arising from fluid flow through the curved channel separate differently-sized particles into different transverse sections of the channel. A detector downstream from the particle size selector specifically detects particles in one or more transverse sections of the channel.

Abstract: A concentration measuring device having a spot-application region, and a configuration capable of measuring the concentration of an object component in the sample liquid dropped on the spot-application region, the concentration measuring device including: a light irradiation device, which is provided on a side below the spot-application region, for emitting an irradiation light having a wavelength absorbable by a coloring matter in the dropped sample liquid. The irradiation light passes through the spot-application region, thereby the sample liquid dropped on the spot-application region is irradiated with the irradiation light from the side below the spot-application region. As a result, a non-covered region in the spot-application region can be easily found by visual observation. The spot-application region is composed of, for example, a through hole formed on the supporting film and a separation membrane that blocks the through hole.

Abstract: A probe including a multiple lens array is disclosed to measure velocity distribution of a moving surface along many lines of sight. Laser light, directed to the moving surface is reflected back from the surface and is Doppler shifted, collected into the array, and then directed to detection equipment through optic fibers. The received light is mixed with reference laser light and using photonic Doppler velocimetry, a continuous time record of the surface movement is obtained. An array of single-mode optical fibers provides an optic signal to the multiple lens array. Numerous fibers in a fiber array project numerous rays to establish many measurement points at numerous different locations. One or more lens groups may be replaced with imaging lenses so a stereo image of the moving surface can be recorded. Imaging a portion of the surface during initial travel can determine whether the surface is breaking up.

Abstract: An optical liquid sensor utilizing a light source, fiber optic cables, a light detector and an irregular transparent surface is provided to detect the presence of liquid in mist and continuous form. The sensor may be integrated into a probe designed for insertion into a pressurized fluid process.

Abstract: A gas analyzing apparatus includes a probe for measuring a concentration of sample gas flowing in a pipe by an optical measurement system. Influence of a thermal lens effect phenomenon is suppressed so that measurement accuracy is improved. The apparatus includes a probe tube disposed to cross a flow path of the sample gas in the pipe to introduce the sample gas flowing in the pipe to a predetermined hollow measurement region. A light emission portion and a light receiving portion for project measurement light to the measurement region in the probe tube and receive the measurement light after passing through the sample gas in the measurement region. A purge gas feed tube disposed in the probe tube supplies purge gas to a region between the optical system members and the measurement region, with a gap to the inner wall surface of the probe tube.

Abstract: A fluid analysis method is provided. A gradient distribution of a first scalar property of a calibration fluid in a space is obtained. A calibration schlieren image of the calibration fluid is acquired and processed to obtain an intensity distribution of the calibration schlieren image. The gradient distribution of the first scalar property of the calibration fluid in the space is mapped to the intensity distribution of the calibration schlieren image, so as to obtain a corresponding relation between the gradients of the first scalar property and the intensities. A test schlieren image of a test fluid is acquired and processed to obtain intensity distribution of the test schlieren image. The intensity distribution of the test schlieren image is converted to the gradient distribution of the first scalar property of the test fluid according to the corresponding relation. Moreover, a fluid analysis system is also provided.

Abstract: The present disclosure is related to a microfluidic flow analyzer for pathological detection. The microfluidic flow analyzer comprises plurality of buffer channels, sample channel, central flow channel, plurality of exciting optical channels and plurality of receiving optical channels. The plurality of exciting optical channels and the plurality of receiving optical channels are placed at predetermined angle to the central flow channel. The plurality of exciting optical channels excite cell in the sample solution flowing through the central flow channel. The cell being excited produces one or more optical signals. The one or more optical signals are received by the plurality of receiving optical channels. The microfluidic flow analyzer comprises plurality of detectors placed on each of the plurality of receiving optical channels for detecting one of the one or more optical signals. The detected optical signal is sent to a computing unit for pathological detection.

Abstract: A system and method for the retrieval of mass density distributions or “profiles” for at least a portion of the Earth's atmosphere for one or more molecular constituent within the atmosphere that absorbs spectral energy. The spectral energy may be anywhere within wavelengths of radiation from UV through visible and into the infrared. The system incorporates a single ended instrument to permit continuous monitoring of the vertical profiles of all constituents of interest.

Abstract: Apparatus and methods for monitoring platelet quality are disclosed. A bag of platelet concentrate is oriented in a desired manner on a transparent surface that is illuminated from one side with a light source. A clamp applies pressure to a desired portion of the bag to temporarily manipulate a predetermined portion of the bag and therefore the fluid in the bag in a known and repeatable manner. A flow inducing member applies pressure to the bag to thereby cause a turbulent flow of the fluid from the bag through a flow path. A detector records optical characteristics of light diffracted by the flowing particles, which is analyzed by software to derive a score correlating to the quality of the platelets. Platelet swirl is scored as a measure of platelet quality where more resting, discoid platelets result in a higher score.

Abstract: A method for characterizing the dielectric response of a fluid includes receiving the fluid into a portion of a flow line that is disposed proximate to a photonic bandgap (PBG) resonant cavity so that a dielectric permittivity of the fluid affects a frequency response of the resonant cavity. The method further includes providing electromagnetic waves to the resonant cavity and measuring a frequency response of the resonant cavity in the presence of the fluid in the flow line. The method further includes determining a property of a resonant mode of the resonant cavity using the frequency response and determining a property of the fluid using the property of the resonant mode.

Abstract: A system and method for analyzing a particle in a sample stream of a flow cytometer or the like. The system has a light source, such as a laser pointer module, for generating a low powered light beam and a fluidics apparatus which is configured to transport particles in the sample stream at substantially low velocity through the light beam for interrogation. Detectors, such as photomultiplier tubes, are configured to detect optical signals generated in response to the light beam impinging the particles. Signal conditioning circuitry is connected to each of the detectors to condition each detector output into electronic signals for processing and is designed to have a limited frequency response to filter high frequency noise from the detector output signals.

Abstract: A method for detecting clots in a liquid is presented. The liquid is in a sample container. Light is irradiated having a first wavelength to the sample container by a first light source at a changeable vertical irradiating position (P—0 to P_n) such that the light irradiated by the first light source passes through the sample container along a first measurement path. An intensity of light having the first wavelength passing along the first measurement path and exiting the sample container is measured. Clots are detected in response to the measured intensity.

Abstract: There is provided a single particle detection technique based on a scanning molecule counting method, enabling individual detection of a single particle using light measurement with a confocal or multiphoton microscope, and quantitative observation of conditions or characteristics of the particle. The inventive technique of detecting a single particle in a sample solution detects light containing substantially constant background light from a light detection region with moving the position of the light detection region of the microscope in a sample solution to generate time series light intensity data; and detects individually a light intensity reduction occurred when a single particle which does not emit light (or a particle whose emitting light intensity in a detected wavelength band is lower than the background light) enters in the light detection region in the time series light intensity data as a signal indicating the existence of each single particle.

Abstract: A method and apparatus for determining the location of a phase boundary such as a fill level, in a vessel. The method includes: providing at least one source of radiation capable of emitting radiation through a portion of the interior of the vessel; providing a plurality of radiation detectors, each detector being capable of detecting, within a part of the measurement range, radiation emitted by the source; and providing a data processing unit for calculation of the position of the phase boundary from the amount of radiation detected by the detectors, wherein the data processing unit calculates the position of the phase boundary from the amount of radiation detected by the detectors by: (i) in a first step, determining within which detector stage the phase boundary is located; and then (ii) in a second step, determining the position of the phase boundary within the detector stage determined in (i).

Abstract: Disclosed are systems and methods for monitoring a multiphase fluid and determining a characteristic of the multiphase fluid. One system includes a flow path containing a fluid, at least one integrated computational element configured to optically interact with the fluid and thereby generate optically interacted light, at least one detector arranged to receive the optically interacted light from the at least one integrated computational element and generate an output signal corresponding to at least one characteristic of a phase of the fluid, and a signal processor communicably coupled to the at least one detector and configured to determine the at least one characteristic of the phase of the fluid.

Abstract: Systems and methods for determining liquid depth information in a condensate pan of a climate control unit are provided. The systems and methods radiate a light beam into a liquid contained in a condensate pan associated with a climate control unit. The light beam is detected at a point of the condensate pan that is below a surface of the liquid. Information related to the depth of the liquid is determined based at least in part on the detected light beam. The systems and methods disclosed herein can determine if liquid depth in a condensate pan is greater than a threshold depth and can control evacuation of the liquid from the condensate pan.

Abstract: Disclosed is a portable handheld characteristic analyzer used to analyze chemical compositions in or near real-time. The analyzer may include a portable housing, at least one optical computing device arranged within the portable housing for monitoring a sample, the at least one optical computing device having at least one integrated computational element configured to optically interact with the sample and thereby generate optically interacted light, at least one detector arranged to receive the optically interacted light and generate an output signal corresponding to a characteristic of the sample, and a signal processor communicably coupled to the at least one detector for receiving the output signal, the signal processor being configured to determine the characteristic of the sample and provide a resulting output signal indicative of the characteristic of the sample.

Abstract: Particles of a flow of aerosol are collected and analyzed by passing them through a housing having an inlet area, an outlet area, and a collection and analysis area. A collection electrode has a tip disposed in the flow path in the collection and analysis area. Particles are collected on the tip of the collection electrode. A microwave pulse is applied to the collection and analysis area such that a plasma is created. Atomic emissions produced during at least part of the microwave step are collected for analysis of the ablated particles.

Abstract: An image sensor integrated circuit may contain image sensor pixels. A channel for receiving a fluid with samples may be formed on top of the image sensor. The image sensor pixels may form light sensors and imagers. The imagers may gather images of the samples as the fluid passes over the imagers or when the samples from the fluid adhere to the surface above an imager array. A protective coating may be formed on surfaces of the channel to protect the image sensor pixels and integrated circuit from potentially damaging materials in the fluid, samples, or materials provided for evaluating the samples. The protective coating may be a base-resistant material such as a silylating agent. A cover glass may be attached above the image sensor integrated circuit to form a portion of the channel. The protective coating may be formed on surfaces of the cover glass.

Abstract: There is provided an optical analysis technique which observes a polarization characteristic of a light-emitting particle using the scanning molecule counting method using an optical measurement with a confocal microscope or a multiphoton microscope. In the inventive optical analysis technique, the light detection region is irradiated with excitation light consisting of predetermined polarized light component(s) and the intensity of at least one polarized light component of the light from the light detection region is detected with moving the position of the light detection region of the optical system in a sample solution; a signal of each light-emitting particle is detected individually in the intensity of at least one polarized light component; and based on the intensity of at least one polarized light component of the signal of the detected light-emitting particle, the polarization characteristic value of the light-emitting particle is computed.

Abstract: A measuring transducer for detecting the formation of foam on a liquid, which is movably inserted into the liquid and the density of which is predetermined, or can be set, such that the measuring transducer floats on the surface of the liquid, wherein a device for determining the luminous flux incident on the top side of the measuring transducer is provided to detect the formation of foam on the liquid which, in many cases, is a process sequence property that is important for process optimization, and wherein an evaluation device of the measuring transducer is configured to output a signal for indicating the formation of the foam when the light flux determined undershoots a predefined threshold value.

Abstract: This invention relates to a novel method and a device for determining middle and protein bound uremic toxins in the biological fluids. More specifically, the present invention relates to an optical method utilizing fluorescence, preferable fluorescence of the spent dialysate, and a specific model, including a unique set of optical spectral components at certain wavelengths, to determine, preferable on-line, the concentration of the middle and protein bound uremic toxins such as beta2-microglobulin (B2M), and indoxyl sulfate (IS).