EP0225322A1 - Method for determining the zeta-potential of solid materials - Google Patents

Method for determining the zeta-potential of solid materials

Info

Publication number
EP0225322A1
EP0225322A1 EP85903192A EP85903192A EP0225322A1 EP 0225322 A1 EP0225322 A1 EP 0225322A1 EP 85903192 A EP85903192 A EP 85903192A EP 85903192 A EP85903192 A EP 85903192A EP 0225322 A1 EP0225322 A1 EP 0225322A1
Authority
EP
European Patent Office
Prior art keywords
potential
flow
pressure difference
zeta potential
measuring
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP85903192A
Other languages
German (de)
French (fr)
Inventor
Hans Jörg JACOBASCH
R. Hanke
H. Körber
Josef Schurz
Volker Ribitsch
Christian Jorde
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Forschungsanwendungsgesellschaft Mbh
Original Assignee
Forschungsanwendungsgesellschaft Mbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Forschungsanwendungsgesellschaft Mbh filed Critical Forschungsanwendungsgesellschaft Mbh
Publication of EP0225322A1 publication Critical patent/EP0225322A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/60—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrostatic variables, e.g. electrographic flaw testing

Definitions

  • the invention relates to a method for determining the zeta potential of solids which are in contact with liquids by means of flow potential / flow current measurements.
  • the zeta potential is a measurement variable that provides information about the structure of the electrochemical double layer at the solid / liquid phase boundary.
  • the structure of the electrochemical double layer and thus also the sign and the level of the zeta potential greatly influence numerous processes in nature and technology as well as the processing and use behavior of materials. examples are
  • the zeta potential at the solid / liquid phase boundary is in
  • the liquid used for the measurement is pressed by a compressed gas through capillaries or capillary systems, which are formed by the solid bodies to be examined, and the potential difference which arises as a result of the liquid flow is measured by electrodes which are located on both sides of the capillary system .
  • the zeta potential ⁇ results from the relationship
  • R electrical resistance between the electrodes
  • the prerequisite for the latter method is the conversion of the pressure difference; ⁇ p into an analog electrical signal.
  • the linear pressure change with time is obtained by opening or closing the valve of a nitrogen or compressed air tank in a defined manner via a stepper motor.
  • Both measuring principles require the use of a nitrogen or compressed air tank for the appropriate safety precautions Application must come.
  • the transportation of zeta potential measuring devices to their place of use in process control is made more difficult.
  • the space requirement is considerable.
  • the first-mentioned measuring principle requires a considerable amount of time.
  • the complex control of a stepper motor and the calculation of the quotient E p / ⁇ p from the slope of a straight line are required.
  • the aim of the invention is to reduce the expenditure on equipment for determining the zeta potential and to significantly reduce the time required for the measurement process.
  • the object is achieved in that a pressure difference across a measuring section is generated with the aid of a speed-controlled pump, the pressure difference and the flow potential or the flow flow are measured synchronously, the quotient
  • the invention provides a device for carrying out the method in which a centrifugal pump and a 4-way valve are arranged between a measuring liquid reservoir and a measuring cell, a differential pressure sensor being located between the outlet and inlet of the measuring cell.
  • FIG. 1 shows the schematic structure of the measuring device.
  • a time-variable pressure difference is generated with the help of a speed-controllable centrifugal pump over a measuring section, in which the material to be measured and through which a liquid flows, synchronously with the pressure difference, the flow potential, e.g. measured as a voltage or as a current between the electrodes, and both measured values are simultaneously fed to a microprocessor for processing.
  • the pressure difference is measured with a differential pressure sensor, the output signal of which is a voltage proportional to the pressure difference, which can be processed directly by the microprocessor.
  • the device for carrying out the method is constructed as follows:
  • a pressureless storage container 1 is accommodated, from which a speed-controllable centrifugal pump 2 sucks the measuring liquid 3 and pumps it through a replaceable measuring cell 5 via a built-in conductivity measuring cell 4 and the measuring liquid 3 flows back from the measuring cell 5 into the storage container 1, between one - And exit from the measuring cell 5, a differential pressure sensor 6 is arranged and between the conductivity measuring cell 4 and the exchangeable measuring cell 5 4-way valve 7 is arranged, through which the flow direction through the exchangeable measuring cell 5 can be changed.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Automatic Analysis And Handling Materials Therefor (AREA)

Abstract

Procédé pour déterminer le potentiel électrocinétique zeta dans lequel la pression différentielle nécessaire pour la mesure, engendrée sur un intervalle de mesure, est obtenue à l'aide d'une pompe commandée en agissant sur la vitesse de rotation de celle-ci et où le potentiel d'écoulement ou le courant sont mesurés en synchronisme avec la pression différentielle et où le potentiel zeta est ensuite calculé de manière connue. Avec ce procédé, on diminue le déploiement d'appareillage ainsi que le temps nécessaire à la mesure du potentiel zeta électrocinétique.Method for determining the electrokinetic zeta potential in which the differential pressure necessary for the measurement, generated over a measurement interval, is obtained using a pump controlled by acting on the speed of rotation thereof and where the potential flow or current are measured in synchronism with the differential pressure and where the zeta potential is then calculated in a known manner. With this process, the deployment of equipment is reduced as well as the time required to measure the electrokinetic zeta potential.

Description

Verfahren zur Bestimmung des Zeta-Potentials von Peststoffen Method for determining the zeta potential of pesticides
Anwendungsgebiet der ErfindungField of application of the invention
Die Erfindung betrifft ein Verfahren zur Bestimmung des ZetaPotentials von Feststoffen, die sich im Kontakt mit Flüssigkeiten befinden, über Strömungspotential/Strömungsstrom-Messungen.The invention relates to a method for determining the zeta potential of solids which are in contact with liquids by means of flow potential / flow current measurements.
Das Zeta-Potential ist eine Meßgröße, die Aussagen über den Aufbau der elektrochemischen Doppelschicht an der Phasengrenze Festkörper/Flüssigkeit vermittelt. Die Struktur der elektrochemischen Doppelschicht und damit auch das Vorzeichen und die Höhe des Zeta-Potentials beeinflussen in starkem Maße zahlreiche Vorgänge in Natur und Technik sowie das Verarbeitungs- und Gebrauchsverhalten von Werkstoffen. Beispiele sindThe zeta potential is a measurement variable that provides information about the structure of the electrochemical double layer at the solid / liquid phase boundary. The structure of the electrochemical double layer and thus also the sign and the level of the zeta potential greatly influence numerous processes in nature and technology as well as the processing and use behavior of materials. examples are
- die Filtration von Feststoffen in der chemischen Verfahrenstechnik,- the filtration of solids in chemical process engineering,
- der Flotationsprozeß,- the flotation process,
- Fließvorgänge in erdölführenden Speichergesteinen,- flow processes in petroleum-bearing storage rocks,
- die Textilveredelung,- textile finishing,
- die Herstellung und Verarbeitung von Synthesefaserstoffen und anderen Polymeren,- the manufacture and processing of synthetic fibers and other polymers,
- Membrantransportprozesse in lebenden Organismen,- membrane transport processes in living organisms,
- die Papierherstellung.- papermaking.
Die Messung des Zeta-Potentials vermittelt also wichtige Informationen zu technologisch wichtigen haterialeigenschaften und ermöglicht somit die Kontrolle, Steuerung und Optimierung technologischer Prozesse. Charakterisierung der bekannten technischen LösungenThe measurement of the Zeta potential thus conveys important information on technologically important material properties and thus enables the control, control and optimization of technological processes. Characterization of the known technical solutions
Das Zeta-Potential an der Phasengrenze fest/flüssig ist imThe zeta potential at the solid / liquid phase boundary is in
Prinzip unter Verwendung der elektrokinetischen EffektePrinciple using electrokinetic effects
Strömungspotential/Strömungsström,Flow potential / flow flow,
Eletroosmose,Eletroosmosis,
Elektrophorese,Electrophoresis,
Sedimentationspotential meßbar.Sedimentation potential measurable.
Die Anwendung der beiden letztgenannten Meßprinzipien ist auf feinverteilte Festkörper mit Teilchengrößen < 5 μm beschränkt. Nach dem Strömungspotential/Strömungsstrom- sowie dem Elektroosmose-Prinzip sind dagegen Messungen an beliebig geformten Festkörpern, d. h. an feinen und groben Pulvern, Fasern, Folien, Platten und Stäben möglich, wobei jedoch vorwiegend Strömungspotential-Messungen angewendet werden. Dabei wird allgemein wie folgt vorgegangen:The application of the latter two measuring principles is limited to finely divided solids with particle sizes <5 μm. According to the flow potential / flow flow principle and the electroosmosis principle, on the other hand, measurements on arbitrarily shaped solid bodies, i. H. possible on fine and coarse powders, fibers, foils, plates and rods, however mainly flow potential measurements are used. The general procedure is as follows:
Durch Kapillaren bzw. Kapillarsysteme, die von den zu untersuchenden Festkörpern gebildet werden, wird durch ein komprimiertes Gas die zur Messung verwendete Flüssigkeit gedrückt und die Potentialdifferenz, die infolge der Flüssigkeitsströmung entsteht, wird durch Elektroden, die sich zu beiden beiten des Kapillarsystems befinden, gemessen. Das Zeta-Potential ς ergibt sicn nach der BeziehungThe liquid used for the measurement is pressed by a compressed gas through capillaries or capillary systems, which are formed by the solid bodies to be examined, and the potential difference which arises as a result of the liquid flow is measured by electrodes which are located on both sides of the capillary system . The zeta potential ς results from the relationship
wobei in which
Ep = Strömungspotential η = dynamische Viskosität der Flüssigkeit l = Kapillarlänge ε = relative Dielektrizitätskonstante der Flüssigkeit εo = elektrische FeldkonstanteE p = flow potential η = dynamic viscosity of the liquid l = capillary length ε = relative dielectric constant of the liquid ε o = electric field constant
R = elektrischer Widerstand zwischen den ElektrodenR = electrical resistance between the electrodes
Δp = Druckdifferenz q = KapillarquerschnittΔp = pressure difference q = capillary cross section
bedeuten.mean.
Da normalerweise auch im drucklosen Zustand zwischen den Elektroden vor und nach dem Kapillarsystem eine Potentialdifferenz exis- tiert (Asymmetriepotential), ist es erforderlich, für mehre re Druckwerte zu bestimmen. Dies erfolgt entweder dadruch, daß durch das Öffnen und Schließen des Ventils eines Druccbehälters für ein komprimiertes Gas verschiedene Druckdifferenzen zwischen der Einström- und der Ausströmseite der Meßzelle erzeugt und Ep und Δp mittels eines Millivoltmeters bzw. eines Manometers getrennt gemessen werden und aus der Mittelung von mindestens zweiSince there is normally a potential difference (asymmetry potential) between the electrodes before and after the capillary system even in the depressurized state, it is necessary for several to determine re pressure values. This is done either by opening and closing the valve of a Drucc container for a compressed gas, which creates various pressure differences between the inflow and outflow sides of the measuring cell, and E p and Δp are measured separately using a millivolt meter or a manometer and from the averaging of at least two
Meßwerten der Quotient Ep/Δp errechnet wird; oder dau bei zeitlich konstanter Druckänderung die Funktion Ep = f(p) von einem x-y-Schreiber geschrieben und aus dem Anstieg der erhaltenen Geraden der wuotient Ep /Δp ermittelt wird.Measured values the quotient E p / Δp is calculated; or if the pressure change is constant over time, the function E p = f (p) is written by an xy recorder and the wuotient E p / Δp is determined from the slope of the straight line obtained.
Voraussetzung für das letztgenannte Verfahren ist die Umwandlung der Druckdifferenz; Δp in ein analoges elektrisches Signal. Die lineare Druckänderung mit der Zeit wird dadurch erhalten, daß das Ventil eines Stickstoff- oder Druckluftbehälters über einen Schrittmotor definiert geöffnet oder geschlossen wird. Beide Meßprinzipien erfordern die Verwendung eines Stickstoff- oder Druckluftbehälters, für die entsprechende Sicherheitsvorkehrungen zur Anwendung kommen müssen. Auch wird wegen der Größe und Masse der Druckbehälter der Transport von Zeta-Potential-Meßgeräten zu ihrem Einsatzort bei der Prozeßkontrolle erschwert. Der Platzbedarf ist erheblich. Das erstgenannte Meßprinzip erfordert einen erheblichen zeitlichen Aufwand. Für die Anwendung des zweiten Meßprinzips ist die aufwendige Regelung eines Schrittmotors, sowie die Berechnung des Quotienten Ep/Δp aus dem Anstieg einer Geraden erforderlich.The prerequisite for the latter method is the conversion of the pressure difference; Δp into an analog electrical signal. The linear pressure change with time is obtained by opening or closing the valve of a nitrogen or compressed air tank in a defined manner via a stepper motor. Both measuring principles require the use of a nitrogen or compressed air tank for the appropriate safety precautions Application must come. Also, because of the size and mass of the pressure vessels, the transportation of zeta potential measuring devices to their place of use in process control is made more difficult. The space requirement is considerable. The first-mentioned measuring principle requires a considerable amount of time. In order to use the second measuring principle, the complex control of a stepper motor and the calculation of the quotient E p / Δp from the slope of a straight line are required.
Ziel der ErfindungAim of the invention
Ziel der Erfindung ist es, den apparativen Aufwand zur Bestimmung des Zeta-Potentials zu verringern und den Zeitaufwand für den Meßvorgang bedeutend zu senken.The aim of the invention is to reduce the expenditure on equipment for determining the zeta potential and to significantly reduce the time required for the measurement process.
Darlegung des .Wesens der Erfindung Technische AufgabeStatement of the essence of the invention Technical problem
Der Erfindung liegt die Aufgabe zugrunde, eine Flüssigkeitsströmung entsprechend einer wählbaren Funktion Δp = f(t) ohne Benutzung eines Drucicbehälters zu erzeugen.The invention has for its object to generate a liquid flow according to a selectable function Δp = f (t) without using a pressure container.
Merkmale der ErfindungFeatures of the invention
Erfindungsgemäß wird die Aufgabe dadurch gelöst, daß eine Druckdifferenz über eine Meßstrecke mit Hilfe einer drehzahlgesteuerten Pumpe erzeugt, die Druckdifferenz und das Strömungspotential oder der Strömungsstrom synchron gemessen, der QuotientAccording to the invention the object is achieved in that a pressure difference across a measuring section is generated with the aid of a speed-controlled pump, the pressure difference and the flow potential or the flow flow are measured synchronously, the quotient
gebildet und das Zeta-Potential in bekannter Weise berechnet wird. Vorteilhaft ist es, die Druckdifferenz mit einem piezoresistiven Differenzdruckaufnehmer zu messen und in ein der Druckdifferenz proportionales Spannungssignal umzuformen. Weiterhin sieht die Erfindung eine Vorrichtung zur Durchführung des Verfahrens vor, bei der zwischen einem Meßflüssigkeits-Vorratsbehälter und einer Meßzelle eine Kreiselpumpe und ein 4-WegeHahn angeordnet sind, wobei sich zwischen dem Aus- und Eintritt der Meßzelle ein Differenzdruckaufnehmer befindet.formed and the zeta potential is calculated in a known manner. It is advantageous to measure the pressure difference with a piezoresistive differential pressure sensor and to convert it into a voltage signal proportional to the pressure difference. Furthermore, the invention provides a device for carrying out the method in which a centrifugal pump and a 4-way valve are arranged between a measuring liquid reservoir and a measuring cell, a differential pressure sensor being located between the outlet and inlet of the measuring cell.
AusführungsbeispielEmbodiment
Nachstehend soll die Erfindung ah einem Ausführungsbeispiel näher erläutert werden. In der zugehörigen Zeichnung zeigt Fig. 1 den schematischen Aufbau der Meßvorrichtung. Über einer Meßstrecke, in der sich das Meßgut befindet und die von einer Flüssigkeit durchströmt wird, wird eine zeitlich veränderliche Druckdifferenz mit Hilfe einer drehzahlsteuerbaren Kreiselpumpe erzeugt, synchron mit der Druckdifferenz das Strömungspotential, z.B. als Spannung bzw. als Strom zwischen den Elektroden gemessen, und beide Meßwerte gleichzeitig einem Mikroprozessor zur Verarbeitung zugeführt. Die Druckdifferenz wird mit einem Differenzdruckaufnehmer gemessen, dessen Ausgangssignal eine der Druckdifferenz proportionale bpannung ist, die vom Mikroprozessor direkt verarbeitet werden kann.The invention will be explained in more detail in one embodiment. In the accompanying drawing, Fig. 1 shows the schematic structure of the measuring device. A time-variable pressure difference is generated with the help of a speed-controllable centrifugal pump over a measuring section, in which the material to be measured and through which a liquid flows, synchronously with the pressure difference, the flow potential, e.g. measured as a voltage or as a current between the electrodes, and both measured values are simultaneously fed to a microprocessor for processing. The pressure difference is measured with a differential pressure sensor, the output signal of which is a voltage proportional to the pressure difference, which can be processed directly by the microprocessor.
Weiterhin ist es zweckmäßig, die zeitfunktion Δp = f(t) über die Drehzahlansteuerung der Kreiselpumpe variabel zu gestalten, um für verschiedenes Meßgut die jeweils günstigste zeitliche Druckdifferenzänderung wählen zu können.Furthermore, it is expedient to make the time function Δp = f (t) variable via the speed control of the centrifugal pump in order to be able to select the most favorable temporal pressure difference change for different measured material.
Die Vorrichtung zur Durchführung des Verfahrens ist folgendermaßen aufgebaut:The device for carrying out the method is constructed as follows:
In einem Grundgerät ist ein druckloser Vorratsbehälter 1 untergebracht, aus dem eine drehzahlsteuerbare Kreiselpumpe 2 die Meßflüssigkeit 3 ansaugt und über eine fest eingebaute Leitfänigkeitsmeßzelle 4 durch eine auswechselbare Meßzelle 5 pumpt und die Meßflüssigkeit 3 von der Meßzelle 5 in den Vorratsbehälter 1 zurückfließt, wobei zwischen Ein- und Austritt aus der Meßzelle 5 ein Differenzdruckaufnehmer 6 angeordnet ist und zwischen der Leifähigkeitsmeßzelle 4 und der auswechselbaren Meßzelle 5 ein 4-Wege-Hahn 7 angeordnet ist, durch den die Durchströmrichtung durch die auswechselbare Meßzelle 5 geändert werden kann. In a basic device, a pressureless storage container 1 is accommodated, from which a speed-controllable centrifugal pump 2 sucks the measuring liquid 3 and pumps it through a replaceable measuring cell 5 via a built-in conductivity measuring cell 4 and the measuring liquid 3 flows back from the measuring cell 5 into the storage container 1, between one - And exit from the measuring cell 5, a differential pressure sensor 6 is arranged and between the conductivity measuring cell 4 and the exchangeable measuring cell 5 4-way valve 7 is arranged, through which the flow direction through the exchangeable measuring cell 5 can be changed.

Claims

Patentansprüche Claims
1. Verfahren zur Bestimmung des Zeta-Potentials von Feststoffen über Strömungspotential/Strömungsstrom-Messungen, dadurch gekennzeichnet, daß eine Druckdifferenz über einer Meßstrecke mit Hilfe einer drehzahlsteuerbaren Pumpe erzeugt, die Druckdifferenz und das Strömungspotential oder der Strömungsstrom synchron gemessen, der Quotient1. A method for determining the zeta potential of solids via flow potential / flow current measurements, characterized in that a pressure difference across a measuring section with the help of a speed-controllable pump, the pressure difference and the flow potential or the flow current measured synchronously, the quotient
gebildet und das Zeta-Potential in bekannter Weise berechnet wird.formed and the zeta potential is calculated in a known manner.
2. Verfahren nach Punkt 1, dadurch gekennzeichnet, daß die Druckdifferenz mit einem piezoresistiven Differenzdruckaufnehmer gemessen und in ein der Druckdifferenz proportionales Spannungssignal umgeformt wird.2. The method according to point 1, characterized in that the pressure difference is measured with a piezoresistive differential pressure sensor and is converted into a voltage signal proportional to the pressure difference.
3. Vorrichtung zur Durchführung des Verfahrens nach Punkt 1 und 2, dadurch gekennzeichnet, daß zwischen einem MeßflüssigkeitsVorratsbehälter und einer Meßzelle eine Kreiselpumpe und ein 4-Wege-Hahn angeordnet sind, wobei sich zwischen dem Aus- und Eintritt der Meßzelle ein Differenzdruckaufnehmer befindet.3. Device for performing the method according to items 1 and 2, characterized in that a centrifugal pump and a 4-way valve are arranged between a measuring liquid reservoir and a measuring cell, with a differential pressure transducer being located between the outlet and inlet of the measuring cell.
Hierzu 1 Blatt Zeichnung 1 sheet of drawing
EP85903192A 1984-07-09 1985-07-08 Method for determining the zeta-potential of solid materials Withdrawn EP0225322A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DD26502184 1984-07-09
DD265021 1984-07-09

Publications (1)

Publication Number Publication Date
EP0225322A1 true EP0225322A1 (en) 1987-06-16

Family

ID=5558647

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85903192A Withdrawn EP0225322A1 (en) 1984-07-09 1985-07-08 Method for determining the zeta-potential of solid materials

Country Status (3)

Country Link
EP (1) EP0225322A1 (en)
AU (1) AU4602785A (en)
WO (1) WO1986000707A1 (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0327545B1 (en) * 1986-09-30 1996-12-04 Colloidal Dynamics Pty. Ltd. Determination of particle size and electric charge
HU194998B (en) * 1986-10-28 1988-03-28 Mta Kutatasi Eszkoezoeket Kivi Test method for detecting zeta potential of suspended substance in liquid medium
US5245290A (en) * 1989-02-27 1993-09-14 Matec Applied Sciences, Inc. Device for determining the size and charge of colloidal particles by measuring electroacoustic effect
GB9011333D0 (en) * 1990-05-21 1990-07-11 Paper Chemistry Lab Inc A method and apparatus for measuring an electrical characteristic of a fibrous dispersion
GB9110318D0 (en) * 1991-05-13 1991-07-03 Wiggins Teape Group Ltd Streaming potential measurement cell
AT414211B (en) * 2002-08-09 2006-10-15 Wolfgang Dipl Ing D Strohmaier Determining functionality of surfactants, useful e.g. for diagnosis of respiratory disease when applied to pulmonary surfactant, comprises measuring electrokinetic properties
AT503235B1 (en) * 2002-08-09 2008-02-15 Volker Dr Ribitsch METHOD AND DEVICE FOR DETERMINING THE FLOW POTENTIAL BZW. ZETA POTENTIAL
AT515744B1 (en) 2014-05-13 2016-08-15 Anton Paar Gmbh A method and apparatus for determining zeta potential for characterizing a solid-liquid phase boundary with controlled pressure profile loading

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3130529C2 (en) * 1981-08-01 1985-01-31 Bayer Ag, 5090 Leverkusen Device for measuring the zeta potential
ATE26888T1 (en) * 1981-11-09 1987-05-15 Wiggins Teape Group Ltd APPARATUS FOR DETERMINING AN ELECTRICAL CHARACTERISTIC OF A FIBER DISPERSION.

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8600707A1 *

Also Published As

Publication number Publication date
WO1986000707A1 (en) 1986-01-30
AU4602785A (en) 1986-02-10

Similar Documents

Publication Publication Date Title
EP0285833A2 (en) Method for determining the concentrations of gases in a gaseous mixture, and probe for measuring the thermal conductivity
EP0254160A1 (en) Device for measuring volume flow in a tube
DE2601487A1 (en) METHOD AND DEVICE FOR VISCOSITY MEASUREMENT
EP0225322A1 (en) Method for determining the zeta-potential of solid materials
DE2411210A1 (en) METHOD AND DEVICE FOR THE ANALYSIS OF REACTION RATES IN CONTINUOUS AND DISCONTINUOUSLY FLOWING SAMPLES
DE2723391A1 (en) DEVICE FOR MEASURING THE DENSITY
EP2944952B1 (en) System for determining the zeta potential for characterising a fixed liquid phase border with controlled pressure profile application
DE10392699B4 (en) High-precision measurement and control of low fluid flow rates
DE19603386A1 (en) Measurement and control of surfactant solution surface tension using bubble excess pressure tensiometer
DE19755183C2 (en) Micro split cell
DE102020114487A1 (en) Thermal flow sensor and method of operating the same
AT503235B1 (en) METHOD AND DEVICE FOR DETERMINING THE FLOW POTENTIAL BZW. ZETA POTENTIAL
DE2104869C3 (en) Method and device for the production of mixed concentrations of defined end values from two liquid components of known initial concentration
EP3968118B1 (en) Method for determining a mean content of a component in a fluid mixture
DE3814735A1 (en) POTENTIOMETRIC SENSOR FOR DETERMINING THE OXYGEN PARTIAL PRESSURE
DE2548518C3 (en) Method and device for determining the ion concentration
DE4236994C2 (en) Method and device for measuring molecular gas diffusion coefficients in liquids
DE102016108964B4 (en) Apparatus and method for determining the mole fraction of gas components of a discrete sample of a multi-component gas mixture
DE3225894C2 (en)
WO2022199960A1 (en) Thermal sensor and method for operating the thermal sensor
DE19540206A1 (en) Zeta potential determining device for fine particles
AT517080B1 (en) Measuring device for measuring the zeta potential of specimens
DD213513A1 (en) ZET APOTENTIAL MEASURING CELL FOR PLATE-FORMAL MATERIAL
DE3224761A1 (en) Method and apparatus for determining the mixing ratio of the components in a gas mixture
DE3609358A1 (en) HARMONIOUS MESSOSCILLATOR FOR DETECTING PHYSICAL PARAMETERS

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE FR GB IT LI LU NL SE

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19860411

RIN1 Information on inventor provided before grant (corrected)

Inventor name: SCHURZ, JOSEF

Inventor name: JORDE, CHRISTIAN

Inventor name: HANKE, R.

Inventor name: JACOBASCH, HANS, JOERG

Inventor name: RIBITSCH, VOLKER

Inventor name: KOERBER, H.