CA1126983A - Method and means for measuring surface tension - Google Patents
Method and means for measuring surface tensionInfo
- Publication number
- CA1126983A CA1126983A CA324,194A CA324194A CA1126983A CA 1126983 A CA1126983 A CA 1126983A CA 324194 A CA324194 A CA 324194A CA 1126983 A CA1126983 A CA 1126983A
- Authority
- CA
- Canada
- Prior art keywords
- liquid
- pump
- container
- drops
- plunger
- 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.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N13/00—Investigating surface or boundary effects, e.g. wetting power; Investigating diffusion effects; Analysing materials by determining surface, boundary, or diffusion effects
- G01N13/02—Investigating surface tension of liquids
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N11/00—Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties
- G01N11/02—Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties by measuring flow of the material
- G01N11/04—Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties by measuring flow of the material through a restricted passage, e.g. tube, aperture
- G01N11/08—Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties by measuring flow of the material through a restricted passage, e.g. tube, aperture by measuring pressure required to produce a known flow
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N13/00—Investigating surface or boundary effects, e.g. wetting power; Investigating diffusion effects; Analysing materials by determining surface, boundary, or diffusion effects
- G01N13/02—Investigating surface tension of liquids
- G01N2013/0241—Investigating surface tension of liquids bubble, pendant drop, sessile drop methods
Landscapes
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- Pathology (AREA)
- Sampling And Sample Adjustment (AREA)
- Reciprocating Pumps (AREA)
- Force Measurement Appropriate To Specific Purposes (AREA)
- Investigating Or Analysing Biological Materials (AREA)
- Basic Packing Technique (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A method of measuring surface tension of liquids which are only available in small quantities, for example the measurement of the surface tension of fetal water to ascer-tain lung development of the fetus. The liquid is discharged from a liquid container by a pump and the pump displacement required to press out each drop from the container is measured.
A method of measuring surface tension of liquids which are only available in small quantities, for example the measurement of the surface tension of fetal water to ascer-tain lung development of the fetus. The liquid is discharged from a liquid container by a pump and the pump displacement required to press out each drop from the container is measured.
Description
The present invention, in the first place, relates to a method of measuring the surface tension of liquids, particularly that of faetal water, in order to establish lung-ripeness or not of the faetus. In the second place, the invention relates to an instrument for carrying out the method in question.
Up till now, for measuring the lung-ripeness of faetuses, time-consuming, unwieldy and undependable methods have been utilized which have caused difficulties in clinical practice.
The present invention has for its object to provide a quick method which enables accurate measuring results to be obtained by simple means This object, according to the invention, is obtained substantially by pressing out a predetermined number of drops of the liquid from a liquid container, and measuring the distance which the liquid in the liquid container has moved at the moment when said predetermined number of drops have left the liquid container. An instrument which is particularly well adapted for carrying out this method is obtained by the fact that a discharge nozzle through which the liquid drips from the container, has a conically divergent end portion with wall portions which taper towards the extreme end to define a sharp end edge, and the noæzle having, additionally, at least one air inlet which enables air and liquid to meet before the liquid will have reached the coni-cally divergent end portion.
The invention will now be disclosed more in detail with reference to the accompanying drawings, in which:-. . . . .
Figure 1 diagrammatically illustrates an instrumentaccording to the invention;
Figure 2 shows a part of the instrument;
Figure 3 is a cross section along the line III-III
in Figure 2; and Figure 4 shows a discharge nozzle forming part of the instrument.
The instrument shown in Figure 1 comprises a liquid container 1 containing a liquid, the surface tension of which is to be measured. Projecting into the liquid container 1 is the plunger 2a of a pump 2 which is operated by a step-by-step motor 3 which is connected to a source of electric current (not shown) through a circuit 4. Circuit 4 comprises a switch 5 for con-trolling the direciton of movement of the motor 3, and thus of the pump 2. The circuit 4 further comprises two micro-type limit switches 6 and 7 adapted to be actuated by a lever 2b forming part of the pump 2. The micro-type limit switches 6 and 7 determine the lenyth of throw of the pump 2, firstly in that the switch 6 will open circuit 4 when, on a downward throw of the pump 2, the lever 2b will reach this switch 6, and secondly in that the switch 7 will open circuit 4 when, on an upward throw of the pump 2, the lever 2b will reach the switch 7.
The motor 3 is connected through a lead 8 to a calcula-tor 9 adapted to calculate the average pump plunger displacement for a number of drops, for instance 10 drops.
The pump plunger 2a is adapted to force out liquid, the surface tension of which is to be measured, from the liquid container 1 into a conduit 10 connected thereto, and down into a succeeding collector pipe 11. The collector pipe 11 is adapted to discharge the liquid into a nozzle 12 which may suitably be carried by a pivoting lever 13, so that the nozzle 12 can be set into various positions relative to the collector pipe 11, for instance.
The nozzle 12 is so designed as to discharge the liquid drip-wise, and drops 14 fall from the nozzle 12 down into a collector vessel 15 while passing by a photocell device which, in a manner well known ~ se, comprises light-emitting unit 16 and a pick-up unit 17, the drops 14 passing between these units. The units 16, 17 of the photocell device are connected to the calculator 9 through leads 18, 19.
In the embodiment shown, the motor 3 is provided with an axis 3a for displacing the plunger 2a of the pump 2. This axis has a thread 3b whi.ch is engaged by a corresponding thread (not shown) in a nut member 2c of the pump 2. The nut member 2c is provided with a flange 2e which i~ reccived in a recess 20 in a fixed member 21 of the instrument, whereby the nut member can no~t be rotated but is displaced at rotation of the axis. The lever 2b and the pump plunger 2a are mounted on the outer end of said nut member 2c.
~126983;
The motor 3 rotates the axis 3a such that the nut member 2c and thereby the plunger 2a are displaced to force liquid out of the liquid container 1. When the lever 2b has reached the limit switch 7 and broken the operation of the motor 3, the collector pipe 11 may be filled with a new liquid, the surface tension of which is to be measured. For filling, the motor 3 is once again started, but so that the axis 3a rotates in the opposite direction. The filling process is completed as soon as the lever 2b reaches the limit switch 6, whereby the operation of the motor is broken.
This filling process is efficient but relatively time-consuming, especially since it is often preferable to give the thread 3b of the axis 3a a smaller pitch in order to attain a very high accuracy of measurement.
The filling process may be accelerated by means of a device illustrated in Figures 2 and 3. In this device, the nut member 2c has no thread for the axis 3a, but a bore 2d through which the axis extends. Furthermore, at least one spring element 22 is mounted in a bore 23 in the nut member 2c and engages on the one hand a fixed plug 25 and on the other hand a body 24, preferably a ball, and press thls towards the axis 3a. The body 24 is shaped so that it may engage the thread 3b of the axis and the spring force is chosen so that the ball 24 is maintained in engagement with the thread for obtaining connection between the motor 3 and the pump plunger 2a for plunger operation and so that the plunger 2a may be pressed back to its starting position by hand. Thereby, the collector pipe may be filled very quickly, namely by pressing down the plunger 2a, e,g, by means of the lever 2b, The ball 24 will then be pressed out of engagement with the thread 3b but rests finally once again in said thread for transferring the movement of the axis 3a to the pump plunger.
One spring element 22 is sufficient per se, but more than one, preferably three symmetrically arranged spring elements are provided and spaced apart so that the balls 24 thereof simultaneously engage the thread 3b of the axis, By means of this device, time can be saved and a more ~imple motor 3 having only one direction of rotation may be used, Additionally, the several symmetrically arranged spring elements 22 facilitate the pressing process and prevent the thread 3b of the axis 3a from being damaged, The nozzle 12 of Figure 4 comprises a receiver portion 12a and a conical discharge-end portion 12b, The hollow interior 12c of the receiver portion 12a is disposed concentrically with the hollow interior 12d of the discharge-end portion 12b, these interior spaces 12c, 12d being interconnected by a centrally disposed restriction 12e, The collector pipe 11 projects downward into the interior space 12c of the receiver portion 12a, on one hand so that the end edge lla of the pipe 11 is disposed in spaced relation above the bottom 12f of the space 12c, and on the other 1~26g8~
hand so that the same is decentered relative to the restriction 12e. As a consequence of this construction, the liquid running down from the collector pipe 11 will contact the air before the liquid will reach the conical discharge-end portion 12b/ whereby an advantageous ejector action will be obtained due to the fact that a free liquid surface will form within the receiver portion 12a.
The conically divergent discharge-end portion 12b comprises wall portions 12h which taper towards the extreme end 12g so as to form a sharp-edged extreme end 12g. Owing to this design the drops 14 are prevented from wetting the outer surface 12b of the nozzle, thus resulting in a stable drop-formation.
Accurate values of the surface tension of the liquid are obtair.ed by pressing out a definite number of drops 14 of the liquid from the liquid container 1, and measuring the way-length described by the liquid within the container 1 as the predetermined number of drops 14 have been discharged from the liquid container 1. The number of drops 14 is counted by the aid of the photocell device, the units 16, 17 of which count the indicated numb~r through leads 18, 19 to the calculator 9, Particularly correct measuring values will be obtained in a simple way by measuring the movement of the liquid in the liquid con-tainer 1 by measuring the numbér of pulses in the circuit 4 through which the motor 3 for operating the pump 2 is driven.
Generally, from a cleaning point of view it is un-favourable if the liquid, the sllrface tension of which is to be measured, should come into contact with the parts of the pump 2.
This problem can be solved simply by causing the liquid in the liquid container 1 to be displaced by the pump 2 through an air cushion.
The method and instrument thus described and illustrated may be varied within the scope of the appended claims. The method, as well as the instrument, can be used for measuring the surface tension of various types of liquids and, suitably, can be used, for instance, for measuring the surface tension of faetal water to ascertain lung-ripeness of a faetus.
'., : ~,
Up till now, for measuring the lung-ripeness of faetuses, time-consuming, unwieldy and undependable methods have been utilized which have caused difficulties in clinical practice.
The present invention has for its object to provide a quick method which enables accurate measuring results to be obtained by simple means This object, according to the invention, is obtained substantially by pressing out a predetermined number of drops of the liquid from a liquid container, and measuring the distance which the liquid in the liquid container has moved at the moment when said predetermined number of drops have left the liquid container. An instrument which is particularly well adapted for carrying out this method is obtained by the fact that a discharge nozzle through which the liquid drips from the container, has a conically divergent end portion with wall portions which taper towards the extreme end to define a sharp end edge, and the noæzle having, additionally, at least one air inlet which enables air and liquid to meet before the liquid will have reached the coni-cally divergent end portion.
The invention will now be disclosed more in detail with reference to the accompanying drawings, in which:-. . . . .
Figure 1 diagrammatically illustrates an instrumentaccording to the invention;
Figure 2 shows a part of the instrument;
Figure 3 is a cross section along the line III-III
in Figure 2; and Figure 4 shows a discharge nozzle forming part of the instrument.
The instrument shown in Figure 1 comprises a liquid container 1 containing a liquid, the surface tension of which is to be measured. Projecting into the liquid container 1 is the plunger 2a of a pump 2 which is operated by a step-by-step motor 3 which is connected to a source of electric current (not shown) through a circuit 4. Circuit 4 comprises a switch 5 for con-trolling the direciton of movement of the motor 3, and thus of the pump 2. The circuit 4 further comprises two micro-type limit switches 6 and 7 adapted to be actuated by a lever 2b forming part of the pump 2. The micro-type limit switches 6 and 7 determine the lenyth of throw of the pump 2, firstly in that the switch 6 will open circuit 4 when, on a downward throw of the pump 2, the lever 2b will reach this switch 6, and secondly in that the switch 7 will open circuit 4 when, on an upward throw of the pump 2, the lever 2b will reach the switch 7.
The motor 3 is connected through a lead 8 to a calcula-tor 9 adapted to calculate the average pump plunger displacement for a number of drops, for instance 10 drops.
The pump plunger 2a is adapted to force out liquid, the surface tension of which is to be measured, from the liquid container 1 into a conduit 10 connected thereto, and down into a succeeding collector pipe 11. The collector pipe 11 is adapted to discharge the liquid into a nozzle 12 which may suitably be carried by a pivoting lever 13, so that the nozzle 12 can be set into various positions relative to the collector pipe 11, for instance.
The nozzle 12 is so designed as to discharge the liquid drip-wise, and drops 14 fall from the nozzle 12 down into a collector vessel 15 while passing by a photocell device which, in a manner well known ~ se, comprises light-emitting unit 16 and a pick-up unit 17, the drops 14 passing between these units. The units 16, 17 of the photocell device are connected to the calculator 9 through leads 18, 19.
In the embodiment shown, the motor 3 is provided with an axis 3a for displacing the plunger 2a of the pump 2. This axis has a thread 3b whi.ch is engaged by a corresponding thread (not shown) in a nut member 2c of the pump 2. The nut member 2c is provided with a flange 2e which i~ reccived in a recess 20 in a fixed member 21 of the instrument, whereby the nut member can no~t be rotated but is displaced at rotation of the axis. The lever 2b and the pump plunger 2a are mounted on the outer end of said nut member 2c.
~126983;
The motor 3 rotates the axis 3a such that the nut member 2c and thereby the plunger 2a are displaced to force liquid out of the liquid container 1. When the lever 2b has reached the limit switch 7 and broken the operation of the motor 3, the collector pipe 11 may be filled with a new liquid, the surface tension of which is to be measured. For filling, the motor 3 is once again started, but so that the axis 3a rotates in the opposite direction. The filling process is completed as soon as the lever 2b reaches the limit switch 6, whereby the operation of the motor is broken.
This filling process is efficient but relatively time-consuming, especially since it is often preferable to give the thread 3b of the axis 3a a smaller pitch in order to attain a very high accuracy of measurement.
The filling process may be accelerated by means of a device illustrated in Figures 2 and 3. In this device, the nut member 2c has no thread for the axis 3a, but a bore 2d through which the axis extends. Furthermore, at least one spring element 22 is mounted in a bore 23 in the nut member 2c and engages on the one hand a fixed plug 25 and on the other hand a body 24, preferably a ball, and press thls towards the axis 3a. The body 24 is shaped so that it may engage the thread 3b of the axis and the spring force is chosen so that the ball 24 is maintained in engagement with the thread for obtaining connection between the motor 3 and the pump plunger 2a for plunger operation and so that the plunger 2a may be pressed back to its starting position by hand. Thereby, the collector pipe may be filled very quickly, namely by pressing down the plunger 2a, e,g, by means of the lever 2b, The ball 24 will then be pressed out of engagement with the thread 3b but rests finally once again in said thread for transferring the movement of the axis 3a to the pump plunger.
One spring element 22 is sufficient per se, but more than one, preferably three symmetrically arranged spring elements are provided and spaced apart so that the balls 24 thereof simultaneously engage the thread 3b of the axis, By means of this device, time can be saved and a more ~imple motor 3 having only one direction of rotation may be used, Additionally, the several symmetrically arranged spring elements 22 facilitate the pressing process and prevent the thread 3b of the axis 3a from being damaged, The nozzle 12 of Figure 4 comprises a receiver portion 12a and a conical discharge-end portion 12b, The hollow interior 12c of the receiver portion 12a is disposed concentrically with the hollow interior 12d of the discharge-end portion 12b, these interior spaces 12c, 12d being interconnected by a centrally disposed restriction 12e, The collector pipe 11 projects downward into the interior space 12c of the receiver portion 12a, on one hand so that the end edge lla of the pipe 11 is disposed in spaced relation above the bottom 12f of the space 12c, and on the other 1~26g8~
hand so that the same is decentered relative to the restriction 12e. As a consequence of this construction, the liquid running down from the collector pipe 11 will contact the air before the liquid will reach the conical discharge-end portion 12b/ whereby an advantageous ejector action will be obtained due to the fact that a free liquid surface will form within the receiver portion 12a.
The conically divergent discharge-end portion 12b comprises wall portions 12h which taper towards the extreme end 12g so as to form a sharp-edged extreme end 12g. Owing to this design the drops 14 are prevented from wetting the outer surface 12b of the nozzle, thus resulting in a stable drop-formation.
Accurate values of the surface tension of the liquid are obtair.ed by pressing out a definite number of drops 14 of the liquid from the liquid container 1, and measuring the way-length described by the liquid within the container 1 as the predetermined number of drops 14 have been discharged from the liquid container 1. The number of drops 14 is counted by the aid of the photocell device, the units 16, 17 of which count the indicated numb~r through leads 18, 19 to the calculator 9, Particularly correct measuring values will be obtained in a simple way by measuring the movement of the liquid in the liquid con-tainer 1 by measuring the numbér of pulses in the circuit 4 through which the motor 3 for operating the pump 2 is driven.
Generally, from a cleaning point of view it is un-favourable if the liquid, the sllrface tension of which is to be measured, should come into contact with the parts of the pump 2.
This problem can be solved simply by causing the liquid in the liquid container 1 to be displaced by the pump 2 through an air cushion.
The method and instrument thus described and illustrated may be varied within the scope of the appended claims. The method, as well as the instrument, can be used for measuring the surface tension of various types of liquids and, suitably, can be used, for instance, for measuring the surface tension of faetal water to ascertain lung-ripeness of a faetus.
'., : ~,
Claims (13)
1. A method of measuring the surface tension of a liquid comprising the steps of:
(a) discharging the liquid from a liquid container by a pump;
(b) forming a drop from the discharged liquid; and (c) measuring the pump displacement necessary to provide the amount of liquid required for forming the drop.
(a) discharging the liquid from a liquid container by a pump;
(b) forming a drop from the discharged liquid; and (c) measuring the pump displacement necessary to provide the amount of liquid required for forming the drop.
2. The method claimed in claim 1, wherein the displacement required to press out each drop of the liquid from the liquid container is measured by recording the number of pulses required to operate the pump to execute said displacement.
3. The method claimed in claim 2, characterized in that the liquid in the liquid container is displaced by the pump through the medium of an air cushion which prevents any contact between the pump and the liquid.
4. The method as claimed in claim 1 a plunger of the pump is movably mounted in relation to a motor-operated driving axis for driving said plunger to force liquid out of said liquid container.
5. The method as claimed in claim 4 wherein the movement of the plunger relative the driving axis is performed by overcoming a spring force which is applied to obtain connection between said driving axis and said plunger.
6. The method as claimed in claim 1 wherein the liquid to be measured is available only in small quantit and the liquid is fetal water the surface tension of which is to be measured to ascertain lung-ripeness of a fetus.
7. The method of measuring the surface tension of a liquid comprising the steps of:
(a) discharging the liquid from a container by a pump having a displaceable member;
(b) operating the pump to effect said discharging step by pulses;
(c) forming a predetermined number of drops from the discharged liquid;
(d) recording the number of pulses required to operate the pump to execute the pump displacement needed to form the predetermined number of drops;
(e) counting the number of drops formed with a sensing device;
(f) calculating, in a calculating device for processing information derived from said recording and counting steps, the pump displacement to discharge each drop of liquid; and (g) computing, from the calculation of pump displacement to discharge each drop, the surface tension of the discharged liquid.
(a) discharging the liquid from a container by a pump having a displaceable member;
(b) operating the pump to effect said discharging step by pulses;
(c) forming a predetermined number of drops from the discharged liquid;
(d) recording the number of pulses required to operate the pump to execute the pump displacement needed to form the predetermined number of drops;
(e) counting the number of drops formed with a sensing device;
(f) calculating, in a calculating device for processing information derived from said recording and counting steps, the pump displacement to discharge each drop of liquid; and (g) computing, from the calculation of pump displacement to discharge each drop, the surface tension of the discharged liquid.
8. The method claimed in claim 7 wherein said step of form-ing a predetermined number of drops includes the further steps of:
(a) sending the discharged liquid through and out of a liquid discharge pipe to expose the liquid to air;
(b) directing the liquid from the discharge pipe into eccentric communication with a nozzle to enhance the exposure to air and to create an ejection action in the nozzle, which nozzle has a conically diver-gent discharge end; and (c) passing the liquid through the nozzle to form stable drops by preventing outside wetting of the device which forms the drops.
(a) sending the discharged liquid through and out of a liquid discharge pipe to expose the liquid to air;
(b) directing the liquid from the discharge pipe into eccentric communication with a nozzle to enhance the exposure to air and to create an ejection action in the nozzle, which nozzle has a conically diver-gent discharge end; and (c) passing the liquid through the nozzle to form stable drops by preventing outside wetting of the device which forms the drops.
9. A device for measuring the surface tension of a liquid comprising:
(a) a liquid container;
(b) a pump for discharging liquid from said container, said pump having a displaceable member;
(c) a liquid discharge pipe coupled with said pump for receiving and transporting the discharged liquid;
(d) a nozzle disposed downstream of said discharge pipe in spaced, non-sealing relationship therewith for forming the discharged liquid into drops, said nozzle including a receiving portion, a flow restric-tion and a conically divergent end portion which tapers towards an extreme end-edge to form a sharp end-edge; and (e) means for measuring the pump displacement necessary to provide the amount of liquid to form a drop of discharged liquid;
(f) whereby air may contact the liquid as it passes from the discharge pipe to the nozzle to create an ejector action and whereby the passage of liquid through the nozzle forms stable drops to be counted.
(a) a liquid container;
(b) a pump for discharging liquid from said container, said pump having a displaceable member;
(c) a liquid discharge pipe coupled with said pump for receiving and transporting the discharged liquid;
(d) a nozzle disposed downstream of said discharge pipe in spaced, non-sealing relationship therewith for forming the discharged liquid into drops, said nozzle including a receiving portion, a flow restric-tion and a conically divergent end portion which tapers towards an extreme end-edge to form a sharp end-edge; and (e) means for measuring the pump displacement necessary to provide the amount of liquid to form a drop of discharged liquid;
(f) whereby air may contact the liquid as it passes from the discharge pipe to the nozzle to create an ejector action and whereby the passage of liquid through the nozzle forms stable drops to be counted.
10. A method of measuring surface tension of a liquid, com-prising discharging the liquid from a container by the aid of prising discharging the liquid form a container by the aid of a pump and measuring the pump displacement to discharge each drop of liquid from the container by recording the number of pulses required to operate the pump to execute said displacement.
11. A method as claimed in claim 10, wherein the liquid in the container is displaced by the pump through the intermediary of an air cushion which prevents any contact between the pump and the liquid.
12. A method as claimed in claim 10, wherein the pump comprises a plunger for pressing liquid in and out of the container and movably mounted in relation to a motor-operated driving shaft for driving said plunger to force liquid out of said container.
13. A method as claimed in claim 12, wherein a movement of the plunger relative to the driving shaft is obtained by over-coming a spring force which is applied for obtaining a driving connection between said driving shaft and said plunger.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE7803385-9 | 1978-03-23 | ||
| SE7803385A SE7803385L (en) | 1978-03-23 | 1978-03-23 | METHOD OF META VETSKORS SURFACE TENSION AND DEVICE FOR IMPLEMENTING THE METHOD IN QUESTION |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1126983A true CA1126983A (en) | 1982-07-06 |
Family
ID=20334408
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA324,194A Expired CA1126983A (en) | 1978-03-23 | 1979-03-23 | Method and means for measuring surface tension |
Country Status (10)
| Country | Link |
|---|---|
| US (1) | US4228677A (en) |
| JP (1) | JPS54164193A (en) |
| AU (1) | AU520105B2 (en) |
| CA (1) | CA1126983A (en) |
| DE (1) | DE2911028A1 (en) |
| FR (1) | FR2420750A1 (en) |
| GB (1) | GB2017317B (en) |
| IL (1) | IL56925A (en) |
| NL (1) | NL7902327A (en) |
| SE (1) | SE7803385L (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2937476A1 (en) * | 1979-09-17 | 1981-04-02 | Agfa-Gevaert Ag, 5090 Leverkusen | DEVICE FOR MEASURING THE SURFACE TENSION |
| US4646562A (en) * | 1984-10-30 | 1987-03-03 | Miller Brewing Company | Method and apparatus for detecting relative dynamic liquid surface activity |
| JPS62174261U (en) * | 1986-04-24 | 1987-11-05 | ||
| US5121636A (en) * | 1991-10-08 | 1992-06-16 | Wda Contracts Corporation | Surface energy meter |
| DE19646925C1 (en) * | 1996-11-13 | 1998-07-16 | Fraunhofer Ges Forschung | Device for measuring the surface tension of liquids |
| US6119511A (en) * | 1998-04-27 | 2000-09-19 | Surface Tensiometry, Inc. | Method and apparatus to measure surface tension by inverted vertical pull |
| GB0618065D0 (en) * | 2006-09-14 | 2006-10-25 | Inkski Ltd | Management of surface tension and other rheological properties of liquids |
| CN104390888B (en) * | 2014-12-01 | 2016-09-28 | 四川大学 | Hollow cylinder discharging liquid measures the method for liquid surface tension coefficient |
| CN104390889B (en) * | 2014-12-01 | 2016-09-28 | 四川大学 | Transparent glass tube with a scale measures the method for surface tension of liquid |
| CN112683734A (en) * | 2020-11-25 | 2021-04-20 | 江苏科技大学 | Hydrophobic surface performance testing device and method thereof |
| CN114383979B (en) * | 2022-01-21 | 2023-05-02 | 四川大学 | Method for measuring surface tension coefficient of liquid by liquid drop method |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR537548A (en) * | 1921-01-31 | 1922-05-24 | Apparatus for measuring the surface tension of liquids | |
| US2473553A (en) * | 1946-01-07 | 1949-06-21 | Arthur J Stokes | Method of and apparatus for measuring the film strength of liquids |
| US3483737A (en) * | 1968-06-25 | 1969-12-16 | Chevron Res | Apparatus for measuring interfacial tension |
| DE1773754B2 (en) * | 1968-07-02 | 1976-03-25 | Veba-Chemie Ag, 4660 Gelsenkirchen-Buer | DEVICE FOR THE AUTOMATIC MEASUREMENT OF THE MELTING INDEX OF PLASTICS |
| DE2104885A1 (en) * | 1971-02-03 | 1972-08-24 | Teldec Telefunken Decca | Device for measuring surface tension, especially in electroplating baths |
| US3775262A (en) * | 1972-02-09 | 1973-11-27 | Ncr | Method of making insulated gate field effect transistor |
| US3827949A (en) * | 1972-03-29 | 1974-08-06 | Ibm | Anodic oxide passivated planar aluminum metallurgy system and method of producing |
| JPS495431A (en) * | 1972-04-20 | 1974-01-18 | ||
| JPS5731315B2 (en) * | 1974-05-13 | 1982-07-03 |
-
1978
- 1978-03-23 SE SE7803385A patent/SE7803385L/en unknown
-
1979
- 1979-03-21 DE DE19792911028 patent/DE2911028A1/en not_active Withdrawn
- 1979-03-22 IL IL56925A patent/IL56925A/en unknown
- 1979-03-22 US US06/022,903 patent/US4228677A/en not_active Expired - Lifetime
- 1979-03-22 GB GB7910152A patent/GB2017317B/en not_active Expired
- 1979-03-23 FR FR7907351A patent/FR2420750A1/en not_active Withdrawn
- 1979-03-23 AU AU45380/79A patent/AU520105B2/en not_active Ceased
- 1979-03-23 JP JP3498379A patent/JPS54164193A/en active Granted
- 1979-03-23 NL NL7902327A patent/NL7902327A/en not_active Application Discontinuation
- 1979-03-23 CA CA324,194A patent/CA1126983A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| AU520105B2 (en) | 1982-01-14 |
| AU4538079A (en) | 1979-09-27 |
| JPS6142812B2 (en) | 1986-09-24 |
| GB2017317B (en) | 1982-11-10 |
| DE2911028A1 (en) | 1979-10-04 |
| GB2017317A (en) | 1979-10-03 |
| SE7803385L (en) | 1979-09-24 |
| FR2420750A1 (en) | 1979-10-19 |
| JPS54164193A (en) | 1979-12-27 |
| NL7902327A (en) | 1979-09-25 |
| US4228677A (en) | 1980-10-21 |
| IL56925A0 (en) | 1979-05-31 |
| IL56925A (en) | 1982-09-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |