Abstract: The present disclosure relates to a blood hose set, or to an extracorporeal blood circuit, for a single-needle treatment. In some embodiments, the set includes: a patient hose line and a Y-shaped connector or three-way connecter, which is connected to the patient hose line. In some embodiments, the blood hose set does not include any single-needle chamber in a blood path or on a blood side, nor is it connected to any single-needle chamber provided in a blood path or on a blood side. The present disclosure further relates to a control device or closed-loop control device, a blood treatment apparatus, a method for the single-needle treatment, a digital storage medium, a computer program product and a computer program.

Abstract: A method for dosing an injection product into a base product, in particular, for the production of a finishing and/or protective paint product, including the following steps: (a) supply of a mixing device, (b) establishment of a continuous flow of base product, (c) injection of the injection product into the continuous flow for a given time, (d) measurement of the amount of injection product injected, (e) calculation of a desired amount of base product based on the amount of injection product injected, steps (c), (d) and (e) being repeated when the amount of base product having passed since the start of step (c) is equal to the amount of base product desired, the injection product being injected into the base product only during step (c).

Abstract: Powered and non-powered kits for the treatment of fluid in boiler and cooling systems, both open and closed recirculating are disclosed. The kits generally include a fluid container, a fluid connector configured to engage the fluid container, a hose configured for fluid communication with the fluid connector, a port, a fluid container suspension means, and a hose end support member. The fluid container is configured to enclose chemical agents and/or solutions. The port may be formed along the fluid container and be configured to receive the fluid connector. The hose end support member may support at least one portion of the hose at a desired height above the standing fluid to be treated. In embodiments, a metering pump is included with the kits, the metering pump configured to cause a predetermined amount of the chemical agents or solutions to be dispersed from the fluid container.

Abstract: A chromatography system includes a gradient delay volume defined as an overall fluid volume between where gradient is proportioned until an inlet of a chromatography column, a pump pumping a flow of gradient; and at least one valve located downstream from the pump, the at least one valve having a plurality of ports including an inlet port that receives the flow of gradient from the pump and an outlet port through which the flow of gradient exits the at least one valve, the at least one valve having at least two positions. A first position of the at least two positions of the at least one valve increases the gradient delay volume of the chromatography system relative to when the at least one valve is in a second position.

Abstract: In a fluid injection system for dispensing a solution, said fluid injection system comprises a feeder tank having a product to be dispensed therein, an inlet connection for diverting fluid from a flow line to a fluid nozzle means and an outlet connection for dispensing the solution into the flow line or onto a matter.

Abstract: Exemplary embodiments are directed to methods and systems for controlling fluid parameters within a detector. A first and second fluid pump manager control the flow of a first and second fluid to one or more heating/cooling devices, and a mixer receives and mixes the first and second fluids. An optical detector flow cell receives the fluid mixture from the mixer, and a pressure regulator controls the pressure at the optical detector flow cell. Thus, the composition, temperature, and pressure of a fluid mixture entering an optical detector flow cell can be controlled in real time.

Abstract: When a liquid in the column is replaced by carbon dioxide in a supercritical state in the chromatograph, an operation of a first pump is controlled by a flow rate control unit, and the carbon dioxide in the supercritical state is supplied at a constant pressure. Moreover, when a flow rate of the carbon dioxide in the supercritical state reaches a predetermined flow rate thereafter, the flow rate control unit controls an operation of the first pump so that the carbon dioxide in the supercritical state is supplied at a constant flow rate.

Abstract: In order to accurately calculate an estimated flow rate by a dynamic constant volume method, a flow rate calculation system including a tank into which fluid flows, an inflow line through which the fluid flows into the tank, and a pressure sensor that detects the pressure inside the tank is adapted to include: a pressure change data storage part that stores pressure change data indicating a temporal change in the pressure detected by the pressure sensor during an inflow period; a flow rate calculation part that calculates the estimated flow rate during the inflow period based on a pressure change rate; and a flow rate correction part that, on the basis of first pressure detected by the pressure sensor after a predetermined time has elapsed after the inflow period and second pressure included in the pressure change data and higher than the first pressure, corrects the estimated flow rate.

Abstract: A liquid feeding device includes a discharge channel, a pump part, a feeding pressure sensor, a non-discharge pressure sensor, a pre-compression part, and a pre-compression speed determination part. The pump part has plunger pumps connected in series or parallel. At least one of the plunger pumps is a closed pump in which communication with the discharge channel is disconnected during a non-discharge time. The pre-compression part causes the closed pump that is after the suction process for sucking the liquid into a pump chamber is completed and during the non-discharge time to execute a pre-compression process to perform a discharge operation until a non-discharge pressure is substantially the same as a feeding pressure based on output of the feeding pressure sensor and output of the non-discharge pressure sensor. The pre-compression speed determination part determines a pre-compression speed of the closed pump in the pre-compression process.

Abstract: A method for conveying a fluid of a fluid circuit by means of an electric motor-powered fluid pump of a motor vehicle, in particular an oil pump, wherein by means of the fluid pump a fluid pressure of the fluid circuit is adjusted to a target pressure, and wherein an actual pressure of the fluid is determined without a pressure sensor.

Abstract: A control system for a water treatment apparatus that includes a control valve assembly having a servo chamber in which a stationary port defining signal ports is located. A regeneration control disc sealingly engages and rotates on a planar surface of the port disc and selectively communicates fluid signals to water pressure operated components within the control valve. An electric motor located in a dry chamber is operatively coupled to the regeneration control disc and rotates the disc during a regeneration cycle. An encoder coupled to the control disc monitors its position and movement. A turbine assembly monitors water treated or to be treated and is electronically coupled to a regeneration controller. A sensor emits pulses related to rotation of the usage turbine and communicates these pulses to the controller which uses this information to determine when a regeneration is needed whereupon the drive motor is appropriately energized.

Abstract: Described are an interface module for two-dimensional chromatography and a method of performing a chromatographic separation that may use the interface module. The interface module includes a valve module, a collection needle, a modifier module and a sample storage element. The valve module has a first port configured to receive an eluent from a first chromatography system, a second port configured to provide a fraction obtained from the eluent, a third port and a fourth port. The collection needle and the modifier module are in fluidic communication with the valve module at the third and fourth ports, respectively. The modifier module includes a source of a modifier solvent. The sample storage element is in fluidic communication with the valve module and is configured to receive a volume of the fraction for injection as a sample into a second chromatography system.

Abstract: A fluid pump includes: three or more volume chambers that suction and discharge a fluid sequentially; moving elements that are respectively provided in the volume chambers, move relative to the volume chamber, and suction and discharge the fluid from and to the volume chamber; a cam that abuts against and drives the moving elements; and a driving section that drives at least one of the moving elements and the cam and relatively rotates the moving elements and the cam to discharge the fluid one time from each of the volume chambers in one cycle of the relative rotation, in which, when suctioning and discharging the fluid, regarding a discharge rotation angle ?, ?=(Z/M)×N is satisfied, where the number of volume chambers is M and any integer from 2 to (M?1) is N.

Abstract: A fluid pump includes: three or more volume chambers that suction and discharge a fluid sequentially; moving elements that are respectively provided in the volume chambers, move relative to the volume chamber, and suction and discharge the fluid from and to the volume chamber; a cam that abuts against and drives the moving elements; and a driving section that drives at least one of the moving elements and the cam and relatively rotates the moving elements and the cam to discharge the fluid one time from each of the volume chambers in one cycle of the relative rotation, in which, when suctioning and discharging the fluid, regarding a discharge rotation angle ?, ?=(Z/M)×N is satisfied, where the number of volume chambers is M and any integer from 2 to (M?1) is N.

Abstract: Methods and devices for producing a population of liposomes are provided. Aspects of the methods include applying a centrifugal force to a suspension of liposomes in a manner sufficient to pass the liposomes through a porous membrane to produce a population of liposomes. Aspects of the invention further include devices, systems and kits useful for performing the methods.

Abstract: A method of actuating a double-action pump assembly with a reciprocating plunger includes signaling the reciprocating plunger to stop for a changeover period; while the pump is stopping, signaling the first inlet and outlet valves to close; while the first inlet and outlet valves are closing, signaling the second inlet and outlet valves to open, such that the second inlet and outlet valves begin to mechanically open at least a dwell period after the first inlet and outlet valves have entirely closed; and signaling the reciprocating plunger to begin moving while the second inlet and outlet valves are closing.

Abstract: A dialysis system includes: (i) a source of water made suitable for a dialysis treatment; (ii) at least one concentrate for mixing with the water from the source; (iii) a dialysis fluid pump; and (iv) a disposable set operable with the dialysis fluid pump and in fluid communication with the source of water and the at least one concentrate, the disposable set including a container having a first end and a second end, the container configured to allow the water and the at least one concentrate pumped by the dialysis fluid pump to enter at the second end and exit from the first end to mix for the dialysis treatment.

Abstract: A charging device 10 of a circulating-water utilization system 1 to be constructed in a specific area includes: a wastewater amount measuring unit 18a configured to individually measure an amount of wastewater discharged from each of water consuming members; a water-quality measuring unit 18b configured to individually measure a water-quality index related to a water quality of the wastewater discharged from each of the water consuming members; and a circulating-water fee calculating part 10A configured to calculate a circulating-water fee of each of the water consuming members on the basis of the amount and the water quality of the wastewater discharged from each of the water consuming members.

Abstract: To determine a corrected flow rate value of a mobile phase flowing in a liquid chromatography (LC) system, a flow rate of the mobile phase at a selected reference position in the LC system is measured to produce one or more flow rate values. A model of the LC system is applied to the flow rate value(s) to determine the corrected flow rate value(s). The model includes a distribution of capacitive elements and resistive elements arranged according to a topology of the LC system. The capacitive and resistive elements are representative of system and solvent properties affecting flow rate while operating the LC system. The system and solvent properties may be properties affecting the flow rate while operating the LC system under dynamic conditions.

Abstract: A compact, modular dosing pump system that is capable of microdose and macrodose volume flow rates, reduces or eliminates the need for additional flow control components such as temperature and pressure sensors, and utilizes a wider operational flow range than existing systems while maintaining the level of accuracy and precision exhibited by conventional dosing pump systems is provided. The dosing pump utilizes a a control system to deliver a range of fluid volumes. The control system monitors the motor emf voltage, calculates the flow rate, and makes adjustments to the pump motor voltage to precisely maintain the desired flowrate.

Abstract: In a method for processing successive fluidic sample portions provided by a sample source, sample reception volumes are filled successively temporarily with at least a respective one of the sample sections, and the sample sections are emptied successively out of the sample reception volumes in such a way, that, while emptying, it is avoided to bring two respective ones of the sample sections, which have not left the sample source directly adjacent to one another, in contact with one another.

Abstract: A control device of a piston pump unit comprising at least two piston-cylinder units that operate in a phase-shifted manner for the purpose of liquid chromatography and to a piston pump unit is described. The control device corrects fluctuations of the system pressure while switching from one piston cylinder unit to the respective other piston cylinder unit. The fluctuations can occur as a result of the cooling of the liquid medium that is heated in an adiabatic manner during a pre-compression phase in the working piston. The control unit controls the piston speed of at least one piston-cylinder unit during the transition phase depending on at least one characteristic, which is ascertained from chronologically previously detected pressure values, such that variations of the system pressure as a result of the cooling of the adiabatically heated medium are at least partially compensated for.

Abstract: A system for blending solutions and a buffer solution is disclosed. In this system a switch valve is present capable of flowing one or more solutions, a low pressure pump for pumping the one or more solutions through the switch valve and a T-joint capable of receiving the one or more solutions through the low pressure pump and blending the one or more solutions with a buffer solution. A high pressure pump is present for collecting a blended solution.

Abstract: A diffuser assembly includes a flexible diffuser membrane and a diffuser body. The flexible diffuser membrane defines a perimeter edge bead along four edges. The diffuser body defines an underlying body portion underlying the flexible diffuser membrane, and a perimeter edge frame covering a covered portion of the perimeter edge bead. The edge frame defines an inside surface that conforms to an outside shape of the covered portion of the perimeter edge bead. The perimeter edge frame is integral to the underlying body portion.

Abstract: The present invention relates to a method of operating a pump generating a flow of a fluid with a pressure, the method comprising operating the pump with a pump speed S satisfying the equation S=Ssimple(1+COR(t)); wherein S is the pump speed, Ssimple is the pump speed disregarding any compression and/or expansion of the fluid, t is a time, and COR(t) is a time dependent correction function; wherein the time dependent correction function COR(t) is a product of a corrective amplitude Acor and a time-dependent function f(t), i.e., COR(t)=Acor·ƒ(t); and wherein the corrective amplitude Acor is set based on a measure for the flow and a measure for the pressure. The present invention also relates to a corresponding use, a pump, a pump system and an HPLC system.

Abstract: The present invention relates to a dialysis machine having a hydraulic system that is intended for providing a dialysis solution or an element of the dialysis solution, wherein the hydraulic system has a degassing pump for degassing the dialysis solution or an element of the dialysis solution, and having a pneumatic system in which a vacuum is present at least at times for operating a component of the dialysis machine, wherein there is a connection line between the suction side of the degassing pump and the pneumatic system for a vacuum generation in the pneumatic system.

Abstract: The invention discloses a method for predicting the pH error during mixing of an aqueous buffer comprising at least one weak acid species and/or at least one weak base species, which comprises the steps of: a) selecting a start composition of the buffer, giving start values for pH and/or buffer concentration; b) calculating the concentrations of all ionic species present in the buffer at a specified pH value from the total composition of the buffer and available dissociation constants; c) calculating the contribution of each of said ionic species to a total pH variance from the specified pH value, the buffer concentration, the calculated concentrations of the ionic species and variances in amounts of buffer components; d) calculating the pH variance, and; e) setting the variance or the square root of the pH variance as the pH error.

Abstract: The invention relates to a method for setting a gradient delay volume GDV of a liquid chromatography system for a chromatography run in liquid chromatography, in particular a high-performance liquid chromatography system, in which a desired value GDVtarget of a gradient delay volume of the liquid chromatography system is ascertained or predefined and, if the value GDVtarget deviates from a specific fixed value GDVactual of a liquid chromatography system, this value GDVtarget is set in a range 0??GDV=GDVtarget?GDVactual?Vmax of a volume of a volume adjustment device 5. Furthermore, the invention relates to an automatic sampler for carrying out such a method.

Abstract: The present disclosure relates to methodologies, systems and apparatus for cooling pump heads and providing balanced cooling and heat transfer between multiple pump heads. Multi-pump systems that are used to pump fluids that vary greatly in density with minor changes in temperature, such as the mobile phase of a CO2-based chromatography system, require highly stable temperature conditions. In order to achieve a substantially equal average heat transfer between multiple pump heads and a coolant fluid, coolant fluid may be flowed through coolant passageways within the pump heads in a recursive and/or parallel coolant flow patterns. Such recursive and/or parallel coolant fluid flow patterns provide increased stability in temperature, compressibility, and density of the fluids passing through a multi-pump system.

Abstract: The invention discloses a piston for a process column, said piston comprising a top side and a bed contact side, wherein said top side comprises a drainage trench.

Abstract: A portable water conditioning system is provided that includes an incoming water inlet; a reverse osmosis stage in fluid communication with the incoming water inlet, the reverse osmosis stage having a permeate outlet and a concentrate outlet; a diversion device having a diversion valve, the diversion valve placing the concentrate outlet in fluid communication with a waste water outlet; a deionizing stage in fluid communication with a pure water outlet; a bypass valve configured to selectively place the permeate outlet in fluid communication with one or more of the waste water outlet, the deionizing stage, and the pure water outlet; and a controller configured to control the diversion device and the bypass valve to provide water at the pure water outlet of a desired condition.

Abstract: A liquid chromatograph comprising a column coupled to a microring resonator array and methods of using the same are disclosed. The microring resonator array measures the bulk refractive index of the mobile phase and any sample injected onto and separated in the column. While carrying out the methods, the composition of a mobile phase passing through the chromatography column may remain substantially constant (isocratic elution) or it may vary (gradient elution). One or more microrings may comprise a covering to act as a thermal control. In addition, the sensor surface may be modified with some type of capture agent that can interact with one or more components in the sample.

Abstract: A water mixer with mixer cartridge (40) with control element (42) and lever handle (31) operable from left to right to control the ratio water flow from respective hot and cold intakes to a single outlet (18), and about a transverse axis to control rate of flow. A mixer body (20) defines a post (22) and a protruding outlet arm (24) at its end. The body defines, at the aforesaid end of the post and extending into the arm, a rim (25) about a recess (26) that receives part of the lever handle in a central off position thereof. In another aspect, lever handle (31) is pivotally mounted to support (50, 150) at a first pivot (52,54) that is fixed against translation and to the control element of the cartridge at a second pivot (48) that is slidable in a slot (39).

Abstract: A method and apparatus for a pump control system. One or more embodiments of the invention include a pump controller that can perform a self-calibrating procedure, can provide precise motor speed control, can provide a limp mode before shutting down the motor when system parameters are exceeded and/or fault conditions occur, can detect fault conditions, and can store fault conditions for later retrieval.

Abstract: Apparatus and methods for high performance liquid chromatography. The apparatus includes a preparation loop comprising two linear stepping pumps, a sample loop comprising a sample injector, a chromatography column, and a detector device. The detector device can include a flash lamp, a flow cell, and a light sensor comprising an entrance slit, a grating; and a charge-coupled device array.

Abstract: A method and system for de-oiling a feed comprising oil and water. The feed has an input temperature above the boiling point of water and an input pressure sufficient to maintain the water in a liquid state. In at least one embodiment, the method comprises pumping the feed with a motive pump through a phase separator having a restriction to effect a phase separation of oil and water in the feed and produce an agitated mixture, supplying the agitated mixture from the phase separator into a pressure vessel operating at a pressure sufficient to maintain in a liquid state water that is at a temperature above the boiling point of water, removing an oil phase from the pressure vessel, and removing a water phase from the pressure vessel.

Abstract: A device for extracting aroma substances from vegetable aroma carriers into a brewing liquid, in particular into beer, includes a fluidized bed extractor accommodating a suspension bed including the brewing liquid and solid particles contained in aroma carriers. The fluidized bed extractor has at least an inlet and an outlet for the brewing liquid. A feed pump pumps the brewing liquid from the inlet through the fluidized bed extractor to the outlet. A feeding speed of the feed pump is set to a value at which an average vertical feeding speed of the brewing liquid in the fluidized bed extractor is lower than an average vertical sedimentation speed of the solid particles in the fluidized bed extractor.

Abstract: Apparatus and method measure the flow rate of fluid for use in calibrating fraction collection in a chromatography system. An injector inserts a detectable substance into a flow of fluid. A first detector, disposed in a path of the flow of liquid with the substance, produces a signal in response to detecting the substance in the flow of fluid. A second detector, disposed downstream from the first detector in the path of the flow of fluid with the substance, produces a signal in response to detecting the substance in the flow of fluid. A computing system receives each signal produced by the first and second detectors upon detecting the substance in the flow of fluid, and computes a volumetric flow rate of the flow of fluid based on a time interval between the signals and a volume of the path between the first and second detectors.

Abstract: This invention describes the equipment and a method to recover starch from a dilute starch stream produced by manufacturing facilities which process the starch-containing materials, such as potato and corn.

Abstract: A device installable into a tap to detect the presence of one or more types of contaminants in the tap water. When the tap is operated, a sample chamber fills with the tap water, such that one or more electronic receivers are capable of detecting the presence of contaminants. Preferably, at least one of the one or more electronic receivers is a photometric sensor for detecting absorption of ultraviolet (UV) light in the 250 nm to 300 nm range. A UV254 LED can be activated when water fills the sample chamber, and a measurement circuit calculates Total Organic Carbon (TOC) by correlation with UV254 absorbance. The device can transmit contamination data, including, but not limited to TOC levels, to a remote apparatus for remote monitoring of the tap water.

Abstract: A secure automated water treatment trailer for inserting chemical in a pipeline, the trailer having a frame with at least one axle and a tongue, a base, a plurality of connected walls, a top engaging each of the plurality of connected walls opposite the base forming an enclosure, a door, a plurality of discharge ports, a plurality of suction ports, a controller in communication with each of the pumps and a network, a plurality of pressure measurement devices, a power supply, a plurality of valves, and a plurality of back pressure control regulators. The secure automated water treatment trailer automatically processes multiple fluids simultaneously into the pipeline. Each fluid has fluid characteristics and a specific gravity.

Abstract: This disclosure is directed to the regulated injection of a chemical(s), solution(s) or material(s) hereafter referred to as chemicals into stormwater runoff, other surface waters or other fluid streams to promote the removal of a pollutant(s) or to alter the properties of the water. Specifically, and depending upon the types of chemicals injected, the physical, chemical and/or biological properties of the water can be altered. The invention provides a passive system to alter stormwater runoff or other surfaces. The system may be deployed at a remote site, such as a construction site, and implemented with minimal or zero external power requirements.

Abstract: A transimpedance amplifier circuit (1) includes an amplifier (22) that amplifies a received signal, an automatic gain control (AGC) circuit (2) that controls the amplification gain of the amplifier by a first time constant in accordance with the level of the received signal, and a first selection circuit (25) that selects the first time constant from a plurality of predetermined values. This can simultaneously implement a short time constant of an AGC function necessary to instantaneously respond to a burst signal and a long time constant of the AGC function necessary to obtain a satisfactory bit error rate (BER) characteristic in a continuous signal by an inexpensive and compact circuit arrangement.

Abstract: A liquid chromatograph analysis method and a liquid chromatograph minimize analysis time when performing analyses by switching columns and mobile phases. Liquid chromatograph 100 for performing a plurality of analyses according to a schedule table includes: mobile phase switching sections 15, 16 for switching a plurality of mobile phases to select a mobile phase to be used in analysis; column switching sections 31, 33 for switching a plurality of columns 32a-32f to select a column to be used in analysis; and control section 60 including memory 61 for storing an equilibration time of each of the plurality of columns 32a to 32f and an equilibration controller 66 for controlling column equilibration. If used columns or used mobile phases are different between two consecutively executed analyses, equilibration controller 66 equilibrates a column used in the later of the two analyses over an equilibration time read out from memory 61.

Abstract: Process for treating effluents containing nitrogen in ammonium form, using a sequential biological reactor (1), according to which: a volume of effluents to be treated in one complete cycle is introduced into the biological reactor in one or more successive fractions by volume, each fraction by volume being treated during a subcycle; each subcycle comprises a phase of feeding with a fraction by volume, and at least a first aerated step, during which total or partial oxidation of the ammonium to nitrites takes place by injection of air or of oxygen into the effluent, a settling out and emptying step taking place after the end of the complete cycle; the weight of N—NH4 to be treated is determined from the volume of effluents in the reactor at the end of the feeding phase, and from the difference between the initial N—NH4 concentration in the reactor and a concentration desired at the end of the aerated step, a maximum aeration time TM is dedicated to the aerated step, and an initial air flow rate Qairinit, for

Abstract: A method and apparatus for producing a biocide from a hypochlorite oxidant and an ammonium salt are provided. The method includes monitoring a control parameter to optimize the ratio between the hypochlorite oxidant and the ammonium salt. The control parameter may be oxidation-reduction potential, conductivity, induction or oxygen saturation.

Abstract: A device for generating high pressure ozone water by using a low pressure ozone gas source includes an ozone gas and water mixture bucket. A water inlet of the ozone gas and water mixture bucket is connected with a tap water inlet through a pipe system and a water inlet solenoid valve. A water outlet of the ozone gas and water mixture bucket is connected with a water outlet through the pipe system and a water outlet one-way valve. An ozone gas inlet of the ozone gas and water mixture bucket is connected with an ozone inlet through the pipe system and an ozone gas inlet one-way valve. The ozone gas and water mixture bucket is provided with an off-gas outlet. The off-gas outlet is connected with a discharge outlet through the off-gas destruct bucket. The water inlet solenoid valve is connected with a power control unit.

Abstract: Provided is a dialysate supply unit and a blood dialyzing apparatus including the dialysate supply unit for supplying dialysate of a dialysate tank to a hemodialyzer and collecting dialysate passing through the hemodialyzer in an effluent tank. The dialysate supply unit includes a dialysate pump, an effluent pump, a first flow-blocking valve, a second flow-blocking valve, and a flow-blocking valve driver. The dialysate pump connects the dialysate tank and the hemodialyzer and the effluent pump connects the hemodialyzer and the effluent tank. The first flow-blocking valve alternately blocks a dialysate outflow tube connecting the hemodialyzer and the dialysate pump and an effluent inflow tube connecting the hemodialyzer and the effluent pump. The second flow-blocking valve alternately blocks a dialysate inflow tube connecting the dialysate pump and the dialysate tank and an effluent outflow tube connecting the effluent pump and the effluent tank. The flow-blocking valve driver drives the flow-blocking valve.

Abstract: A portable hemodialysis system is provided including a disposable cartridge and a reused dialysis machine. The disposable cartridge includes a dialysate flow path and a blood flow path which flow in opposite directions through a dialyzer. The disposable cartridge includes a filter for removing waste products from the dialysate. The reused dialysis machine possesses a reservoir for dialysate, various sensors including a reservoir level sensor assembly, and a processor connected to the various sensors for controlling and monitoring hemodialysis treatment. The reservoir level sensor assembly includes a vertically extending electrode array for transmitting electrical signals to the processor detecting whether the reservoir possesses sufficient dialysate for therapy, and for detecting whether there is a fault condition during therapy such as a loss of dialysate in the reservoir or an increase in fluid in the reservoir which may indicate a failure in the dialysis membrane.

Abstract: A method of preparing a liquid mixture for use in a liquid chromatography system is provided. The mixture comprises one or more acids, one or more bases, one or more salts, and one or more solvents, and the method comprises the steps of: i) calculating pH and/or salt concentration at a particular time t from a user-determined gradient function; and ii) based on the values obtained in step (i), calculating percent acid, percent base, percent salt and percent solvent in the liquid mixture at time t. A liquid chromatography system incorporating such method is also provided.