CN105606569A - Method for measuring transmission rate of liquid adherent boundary layer under effect of external electric field - Google Patents

Abstract

The invention discloses a method for measuring the transmission rate of a liquid adherent boundary layer under the effect of an external electric field. The method comprises the steps that an adherent boundary layer area of liquid is determined according to intensity of the electric field and the liquid thickness in the direction of incident rays, and the incident position of the incident rays on a sample groove is determined according to the adherent boundary layer area; incident light intensity of the incident rays and first transmission light intensity after the incident rays penetrate through the empty sample groove are obtained, and light absorbing intensity of the empty sample groove is determined according to the incident light intensity and the first transmission light intensity; incident light intensity of the incident rays and second transmission light intensity after the incident rays penetrate through the sample groove containing liquid to be measured are obtained; based on the incident light intensity, the light absorbing intensity of the empty sample groove and the second transmission light intensity, the transmission rate of the liquid to be measured is determined. The method can achieve the effect of measuring the transmission rate in the electrorheological fluid/ionic liquid boundary layer under the effect of the external electric field.

Description

The measuring method of the adherent boundary-layer transmissivity of liquid under External Electrical Field

Technical field

The present invention relates to miniature scale physical parameter fields of measurement, relate in particular to liquid under External Electrical Field and pasteThe measuring method of wall boundary-layer transmissivity.

Background technology

Below background of related of the present invention is described, but these explanations might not form thisBright prior art.

At present, check small chi sample transmitance equipment be mainly microscope. Wherein, infrared bandDue to its invisibility, measuring will be far away than visible waveband complexity. Infrared microscope is usually used at presentThe fields such as the prevention of electronic equipment detection failure, infrared thermal imaging, microelectronic chip Conciseness of Reliability Analysis,Be mainly used in measuring the solid exemplar of trace or miniature scale, as: measurement molecule and trace contaminant,Measure multi-level different component polymer, detect semiconductor devices, integrated circuit, printed circuit board (PCB) etc.

After existing theoretical research shows to apply electric field can there is larger change in ionic liquid boundary-layer internal transmission factorChange, know that from academic angle research the logical light behavior in boundary-layer particularly measures energising accuratelyLiquid boundary-layer transmissivity development to basic subject fields such as electrochemistry with the variation of applied voltage in situationThere is very large facilitation. Also be suitable for undoubtedly on measuring mechanism for this problem infrared microscope,But need to solve series of problems, and testing sample groove and experimental system are redesigned, as at presentDirectly test substance made often to slide sample or directly put by infrared/visible microscope measurement of speciesPut on objective table and measure, this mode is no doubt feasible to solid matter, but for liquid substance, byOn objective table, lack the relevant device such as container in order to take up liquid, therefore for measuring the small chi of liquidDegree transmitance needs special processing to be adapted to the sample part that microcosmos area is measured. In addition, because microscope carriesThing platform is all in unlimited and nonocclusive measuring process, to be often easily subject to some such as extraneous veiling glare conventionallyImpact, if test substance exists strong absorption to light, or exist under multifrequency signal input condition, canCause measurement result to occur inaccurate. In the actual use procedure of infrared microscope, if testing liquid is thickDegree is unknown, or liquid layer to be measured is in uneven thickness, cannot be in same position when the microscope causing thus focuses onPut focusing, while causing measuring for every time, the logical luminous intensity of incident light is all different, and above all factors all can be ledMeasure error, causes and cannot accurately obtain the now transmissivity of testing liquid. Publish at presentIn patent or document, there is not yet relevant discussion.

Therefore, in prior art, need one can Measurement accuracy External Electrical Field under liquid miniature scale saturatingPenetrate the technical scheme of rate.

Summary of the invention

The object of the invention is to propose the measurement of the adherent boundary-layer transmissivity of liquid under a kind of External Electrical FieldMethod, can solve the transmissivity measurement in ER fluid/ionic liquid boundary-layer under DC Electric Field and askTopic.

According to the measuring method of the adherent boundary-layer transmissivity of liquid under External Electrical Field of the present invention, comprising:

S1, according to the liquid thickness in electric-field intensity and incident ray direction, determine the adherent of liquidBoundary-layer region, and determine the incident of incident ray on sample cell according to described adherent boundary-layer regionPosition;

S2, make incident ray along the direction perpendicular to liquid levels and electric field, from described incoming positionIncident, obtains the incident intensity of incident ray and incident ray and sees through first after empty sample cellTransmitted intensity, determines that according to incident intensity and the first transmitted intensity the extinction of empty sample cell is strongDegree;

S3, make incident ray along the direction perpendicular to liquid levels and electric field, from described incoming positionIncident, the incident intensity and the incident ray that obtain incident ray see through the sample that testing liquid is housedThe second transmitted intensity after groove;

S4, photon absorbing intensity and the second transmitted intensity based on incident intensity, empty sample cell, determineThe transmissivity of testing liquid;

Wherein, sample cell comprises: base and two battery lead plates; The both sides of base raise up, and makeBase has matrix cross section; The two ends of base arrange respectively a battery lead plate; Battery lead plate isType boss structure, comprising: perpendicular to the battery lead plate main body of base be arranged on battery lead plate main body sideHorizontal projection; Horizontal projection coordinates with the matrix cavity shape of base end; Two battery lead plates respectively withThe both positive and negative polarity of power supply connects, for generation of electric field.

Preferably, horizontal projection extension elongation l in the horizontal direction meets following relation:

l＝1.25/d

$d=\sqrt{\frac{\mathrm{\μ}}{7\mathrm{\ρ}}+\frac{L}{0.01E^{3.5}}}$

In formula, μ is the viscosity of liquid in sample cell, and unit is: Pas; ρ is liquid in sample cellDensity, unit is: g/cm³; L is two distances between battery lead plate, and unit is: cm; E isElectric-field intensity, unit is: v/m.

Preferably, sample cell also comprises cover plate; The horizontal projection of battery lead plate thickness in vertical directionEquate the upper surface of the upper surface of horizontal projection and chassis side projection with the height of projection of chassis sideIn same plane, cover plate covers on chassis side projection and described horizontal projection.

Preferably, the one side chromium plating contacting with liquid of described cover plate is also provided with focusing mark, usesThe benchmark of adjusting as position in the time focusing on.

Preferably, the thickness of cover plate is no more than 3mm.

Preferably, the material of base plate and/or cover plate is: CaF₂Or BaF₂。

Preferably, battery lead plate is surperficial platinum plating titanium or niobium.

Preferably, the depth of parallelism between the depth of parallelism and cover plate and the base plate between two battery lead plates is notBe greater than 0.5%; The processing roughness of battery lead plate is less than Ra1.6; The fineness of base plate and cover plate processing is60-40,3, aperture, the depth of parallelism is not more than 0.5%, in base plate and cover plate without bubble, without scatteringGrain.

Preferably, horizontal projection thickness is in vertical direction no more than 3mm.

Preferably, measuring system according to the present invention further comprises:

Between incident light source and sample cell, chopper is set, the light producing from incident light source, interceptsThe wavelength signals of CF is as incident ray;

Two lock-in amplifiers are set between sample cell and measuring unit, are respectively used to eliminate chopperModulating frequency and ac frequency change the impact bringing, and to entering from the optical signal of sample cell outgoingRow amplifies to be processed.

According to beneficial effect of the present invention:

(1) two ends of sample cell base arrange respectively the battery lead plate being connected with power positive cathode, canFor the liquid in sample cell improves electric field, and then measure the variation of liquid refractivity under External Electrical Field;

(2) both sides of base are raised up, battery lead plate is designed toType boss structure,Horizontal projection is coordinated with the matrix cavity shape of base end, be convenient to accurately obtain liquid in sample cellThe thickness of body, improves the accuracy of measuring structure;

(3) horizontal projection of battery lead plate thickness in vertical direction and the height of projection of chassis sideEquate, the upper surface of the upper surface of horizontal projection and chassis side projection in same plane, base sideOn limit projection and horizontal projection, cover a cover plate, can avoid causing due to surface tension of liquidThe uneven problem of liquid level;

(4) between incident light source and sample cell, chopper is set, can intercepts the ripple of CFLong signal is as incident light source; Two lock-in amplifiers are set between sample cell and measuring unit, oneModulating frequency and ac frequency that chopper can be eliminated in aspect change the impact bringing, and on the other hand canReach and amplify from the optical signal of sample cell outgoing, preventing because the optical signal from sample cell outgoing is too weakCannot obtain or cannot go out liquid refractivity by accurate analysis.

Brief description of the drawings

By the detailed description of the invention part providing referring to accompanying drawing, the features and advantages of the present invention willBecome easier to understand, in the accompanying drawings:

Fig. 1 is according to the measuring method of the adherent boundary-layer transmissivity of liquid under External Electrical Field of the present inventionSchematic diagram;

Fig. 2 a is according to the front view of sample cell base of the present invention, and Fig. 2 b is according to sample of the present inventionThe top view of bottom land seat, Fig. 2 c is according to the left view of sample cell base of the present invention;

Fig. 3 a is according to the front view of sample cell battery lead plate of the present invention, and Fig. 3 b is according to sample of the present inventionThe top view of product groove battery lead plate, Fig. 3 c is according to the left view of sample cell battery lead plate of the present invention;

Fig. 4 a-4e is even according to the depth of parallelism and the electric field of two battery lead plates in the preferred embodiment of the present inventionBetween property, be related to schematic diagram;

Fig. 5 is the flow chart of the adherent boundary-layer transmissivity of measurement liquid of invention preferred embodiment.

Detailed description of the invention

With reference to the accompanying drawings illustrative embodiments of the present invention is described in detail. To exemplary enforcementThe description of mode is only for demonstration object, and is never the restriction to the present invention and application or usage.

According to the measuring method of the adherent boundary-layer transmissivity of liquid under External Electrical Field of the present invention, bagDraw together:

S1, according to the liquid thickness in electric-field intensity and incident ray direction, determine the adherent of liquidBoundary-layer region, and determine the incident of incident ray on sample cell according to described adherent boundary-layer regionPosition;

S2, make incident ray along the direction perpendicular to liquid levels and electric field, from described incoming positionIncident, obtains the incident intensity of incident ray and incident ray and sees through first after empty sample cellTransmitted intensity, determines that according to incident intensity and the first transmitted intensity the extinction of empty sample cell is strongDegree;

S3, make incident ray along the direction perpendicular to liquid levels and electric field, from described incoming positionIncident, the incident intensity and the incident ray that obtain incident ray see through the sample that testing liquid is housedThe second transmitted intensity after groove;

S4, photon absorbing intensity and the second transmitted intensity based on incident intensity, empty sample cell, determineThe transmissivity of testing liquid.

Adopt measuring system as shown in Figure 1 according to measuring method of the present invention, comprising: incident light source10, sample cell 20, power supply 30 and measuring unit 40. The present invention adopts sample cell to hold liquid to be measuredBody, sample cell 20 comprises: base 21 and two battery lead plates 22. Wherein, two side direction of base 21Projection, makes base 21 have matrix cross section; The two ends of base 21 arrange respectively an electrodePlate 22. Fig. 2 a is according to the front view of sample cell base of the present invention, and Fig. 2 b is according to sample of the present inventionThe top view of product bottom land seat, Fig. 2 c is according to the left view of sample cell base of the present invention. 21 liang of basesTwo battery lead plates at two projections of side and base two ends form four sides of sample cells 20, thisThe semi-closed structure of four side formation can be for holding testing liquid. Because sample cell 20 is to lightThe absorption of signal, optical signal sees through after sample cell 20 and can be weakened, if from sample cell 20 outgoingOptical signal too a little less than, easily make measuring unit 40 to go out according to weak optical signal accurate analysisThe refractive index of sample cell 20 interior liquid, even makes measuring unit 40 obtain less than optical signal. ForAvoid the generation of this situation, can make the seeing through of optical signal of the designated wavelength range of sample cell 20Rate is not less than a certain threshold value, as 90%. Preferably, for the ease of the transmission of optical signal, base plate 21The material of base plate 21 can be CaF₂Or BaF₂。

Battery lead plate 22 isType boss structure, comprising: perpendicular to the battery lead plate main body of base 21221 and be arranged on the horizontal projection 222 of battery lead plate main body 221 sides. Fig. 3 a is according to of the present inventionThe front view of sample cell battery lead plate, Fig. 3 b is according to the top view of sample cell battery lead plate of the present invention, figure3c is according to the left view of sample cell battery lead plate of the present invention. Horizontal projection 222 and base 21 endsMatrix cavity shape coordinates, and the semi-closed structure forming can be for holding testing liquid. Two electricityPole plate 22 is connected with the both positive and negative polarity of power supply 30 respectively, in the time of opening power 30, and two battery lead plates 22Between produce electric field, make liquid in sample cell 20 under External Electrical Field.

In the process that common metal uses as anode, can constantly dissolve, make to exist between itself and coatingSpace, the coating on surface can hightail along with the dissolving of this metal anode. Because titanium, niobium etc. belong toValve metal, can passivation while directly use as electrode anode and stop reaction and conduction, so self is notCan dissolve and corrosion, in the time using the valve metals such as titanium, niobium as electrode anode, be not easy because substrate is moltenSolution causes platinum coating to come off, and the conductive coating life-span is longer. Therefore, according to a preferred embodiment of the invention.Titanium or niobium that battery lead plate 22 is surperficial platinum plating.

The extension elongation of horizontal projection mainly determines by the boundary layer thickness of liquid, final again by liquidElectrochemistry properties is fixed, and under DC Electric Field, the size of field intensity inhomogeneities determines. Boundary-layer is thickSpend greatly, the extension elongation of the horizontal projection of counter electrode plate can be less, as long as can ensure enoughTesting distance. Preferably, horizontal projection extension elongation l in the horizontal direction meets as ShiShimonosekiSystem:

l＝1.25/d

$d=\sqrt{\frac{\mathrm{\μ}}{7\mathrm{\ρ}}+\frac{L}{0.01E^{3.5}}}$

In formula, μ is the viscosity of liquid in sample cell, and unit is: Pas; ρ is liquid in sample cellDensity, unit is: g/cm³; L is two distances between battery lead plate, and unit is: cm; E isElectric-field intensity, unit is: v/m.

Horizontal projection thickness in vertical direction is mainly determined by the absorption coefficient of liquid, horizontal projectionMore thin being more difficult to processes. If horizontal projection is too thick and sample cell in liquid thickness to be less than horizontal projection thickSpend, be not easy to the interpolation of testing liquid, be also unfavorable for that the liquid in Obtaining Accurate sample cell is thick simultaneouslyDegree; If the liquid thickness in horizontal projection sample cell equates with horizontal projection thickness, can pass through waterThe thickness of liquid in the thickness Obtaining Accurate sample cell that plano-convex rises, but now the thickness of horizontal projection is moreGreatly, corresponding can the increase of liquid thickness in sample cell, if the excessive easy weakening transmission of liquid absorption coefficientOptical signal, make measuring unit cannot obtain optical signal transmissive or the optical signal transmissive that obtains too a little less than,So that cannot obtain the transmissivity of the adherent boundary-layer of liquid. Therefore according to different types of liquid, levelThe thickness of projection can respective change, under the condition that can reach machining accuracy, do as far as possible thin oneA bit. According to a preferred embodiment of the invention, horizontal projection thickness is in vertical direction no more than 3mm.

In theory should keeping parallelism, still actual processing or making sample between two battery lead plates 22When groove, due to mismachining tolerance, between two battery lead plates, be difficult to reach completely parallel. If battery lead plate 22Not parallelly will cause liquid internal electric field intensity distribution inequality, and cause the fluid transmittance in certain area to surveyAmount result is inconsistent, causes larger measure error. In addition, by adding the liquid bulk in sample cellWhen cross-sectional area long-pending and sample cell is determined the liquid thickness in incident ray direction, if sample cell twoThe battery lead plate 22 of end is not parallel, and the liquid thickness obtaining is according to the method described above inaccurate, also can be rightMeasurement result exerts an influence. Therefore,, in order to ensure the accuracy of measurement result, be necessary to make two electricityPole plate 22 keeps certain depth of parallelism.

For the machining accuracy of the Electrode depth of parallelism is on the inhomogeneity impact size of field intensity, pin of the present inventionAdopt the method for numerical simulation to study the Different electrodes depth of parallelism to the rectangular duct of 50mm × 5mmTime, the distribution situation of electric field strength when additional 1V voltage, the spacing between two battery lead plates is5mm. Numerical simulation shows, by the testpieces size designing in this figure, Fig. 4 a-4e shows basisIn the preferred embodiment of the present invention, the relation between the depth of parallelism and the field uniformity of two battery lead plates, figureIn, from the depth of parallelism of Fig. 4 a-Fig. 4 d be respectively 5%, 2.5%, 1% and 0.5%, Fig. 4 e in twoBattery lead plate is completely parallel, and the unit of electric-field intensity is V/m, and the larger surface field intensity of gray value is larger,The uniformity of the larger surface field of gray value difference is poorer. Can find out two electrodes from Fig. 4 a-4ePlate is complete when parallel, and the uniformity of electric-field intensity is best, when incomplete when parallel between two battery lead plates,The depth of parallelism is less, and the uniformity of electric-field intensity is better. In the time that between two electrodes, the depth of parallelism is less than 0.5%,The numerical fluctuations of liquid internal field intensity (feelings when maximum/minimum of a value is compared uniform electric field in incident light directionCondition) be less than 0.5%, and mainly concentrate on upper and lower two end regions of light path, light path middle part field intensity and even electricity fieldField does not almost change.

For the impact on transmissivity measurement result of the numerical fluctuations 0.5% of investigating liquid internal field intensity,Under the condition of Fig. 4 d, continue to investigate field intensity as an example of methyl-propyl iodonium imidazolide salts example and change transmissivityThe impact of measurement result. The complex refractivity index of mediumWith multiple relative dielectric constant ε(ω)＝ε₁(ω)+iε₂(ω) pass between is [n (ω)+i κ (ω)]²＝ε₁(ω)+iε₂(ω), there are real part and imaginary part respectivelyEquate, obtain

n(ω)²-κ(ω)²＝ε₁(ω)2n(ω)κ(ω)＝ε₂(ω)

And absorption coefficient (ω) is directly proportional to extinction coefficient κ (ω), the two presents lower relation of plane:

$\mathrm{\α}\left(\mathrm{\ω}\right)=\frac{2\mathrm{\ω}\mathrm{\κ}\left(\mathrm{\ω}\right)}{c}=\frac{2h\mathrm{\κ}\left(\mathrm{\ω}\right)}{c}$

Wherein ω is angular frequency, and f is frequency, and c is the light velocity;

When wavelength is 1520nm, when voltage is 0V, refractive index is 1.56292, and absorption coefficient is0.474cm^-1, electrical conductivity is 0.8ms/cm^-1, the value that now calculates κ (ω) is1.52 × 10-4 × 0.474/2/3.14=1.132 × 10-5cm-1, calculates ε thus₁(ω) value is2.44272-1.28×10-10＝2.44272，ε₂(ω) value is 0.00000035845;

When wavelength is 1520nm, when voltage is 1V, refractive index is 1.56287, and absorption coefficient is0.775cm^-1, electrical conductivity is 0.8ms/cm, the value that now calculates κ (ω) is1.52×10-4×0.775/2/3.14＝1.875×10-5cm^-1, calculate thus ε₁(ω) value is2.44256-3.515×10-10＝2.44256，ε₂(ω) value is 0.00000058607;

When wavelength is 1520nm, when voltage is 2V, refractive index is 1.56276, and absorption coefficient is0.852cm^-1, electrical conductivity is 0.8ms/cm, the value that now calculates κ (ω) is1.52×10-4×0.852/2/3.14＝2.062×10-5cm^-1, calculate thus ε₁(ω) value is2.44222-4.252×10-10＝2.44222，ε₂(ω) value is 0.00000064448;

When wavelength is 1520nm, when voltage is 3V, refractive index is 1.56266, and absorption coefficient is0.945cm^-1, electrical conductivity is 0.8ms/cm, the value that now calculates κ (ω) is1.52×10-4×0.945/2/3.14＝2.287×10-5cm^-1, calculate thus ε₁(ω) value is2.4419-5.23×10-10＝2.4419，ε₂(ω) value is 0.00000071476;

All to be that 5cm, supply voltage are from 1V for the distance between two battery lead plates due to above voltageChanging to 3V is example, and now field intensity has increased twice (field intensity is changed to 200%), and ε₁(ω) only change1.392 × 10-4, ε₂(ω) also just changed 9.96%, analyzed accordingly, can ignore field intensity and change 0.5%The error that experimental result is caused. Therefore, according to a preferred embodiment of the invention, two battery lead platesThe depth of parallelism remains in 0.5%.

Battery lead plate 22 can be connected with power supply 40 by wire. Such as, one end of wire is welded onOn battery lead plate, the other end of wire is connected with the negative or positive electrode of power supply; For another example, on battery lead plateUnit is stretched out in setting, and one end of wire is connected with battery lead plate by geometrical clamp, or this stretches out on unitOffer the aperture for connecting wire, one end of wire is directly wrapped on this aperture. According to the present inventionPreferred embodiment, on battery lead plate, be provided with and the integrated unit 50 that stretches out of battery lead plate so that withPower supply connects, as shown in Fig. 3 a, 3b. Tiny platinum filament is connected with platinized platinum by argon arc welding, at platinumSilk overcoat layer protective layer, thus prevent that the wall of platinum filament and optical spectrometer sample chamber is sent out in measuring processRaw contact causes electric leakage; Or, clamp platinized platinum with electrode holder and have more the part of glass guide channel, and use wireElectrode holder is connected with outside power supply 40.

The base of sample cell and two electrode plate can be bonded together by optics cold glue, when bonding, needNotice that optics cold glue can not ooze out gummed horizontal plane, so as not to microscope by exerting an influence, glue simultaneouslyWhile closing, must ensure that two battery lead plates remain the state vertical with base. After having glued together, put into dryAfter the dry 12h of case, pour testing liquid into, then leave standstill 6h, to guarantee that liquid in sample cell is without leakage.According to a preferred embodiment of the present invention, in the time measuring, first sample cell is placed onOn the mobile platform of Bruker-hypersion infrared microscope, the surrounding of sample cell place clay withThe position of fixed sample groove.

The liquid of close battery lead plate is due to capillary existence, and its liquid is inhomogeneous, thereby can be to enteringPenetrate light and produce refraction and/or reflection problems, affect the accuracy of measurement result. In addition, work as sampleHour, under the effect of surface tension of liquid, the liquid level of liquid is easily uneven for liquid thickness in groove,Make the liquid thickness at different incoming positions place inconsistent, affect the accuracy of measurement result. In order to disappearExcept surface tension of liquid to measurement result preferably, can design a cover plate 23 for sample cell, and makeThe thickness in vertical direction of horizontal projection of battery lead plate equates with the height of projection of chassis side, waterThe upper surface of the upper surface that plano-convex rises and chassis side projection, in same plane, ensures in sample cellLiquid thickness equates with the thickness of horizontal projection, then on chassis side projection and horizontal projection,Be that liquid level upside covers cover plate, make liquid level parallel with the extension of horizontal projection, so just canEnsure the consistent of the interior liquid thickness of sample cell, avoid the liquid level injustice causing due to surface tension of liquid to askTopic.

In order to improve repeatedly accuracy and the accuracy of measurement result, before each measurement, need to pass throughThe position of adjusting sample cell focuses on. According to a preferred embodiment of the invention, cover plate 23 withThe one side chromium plating of liquid contact is also provided with focusing mark, the base of adjusting as position when focusing onStandard, such as, according to the thickness range of the adherent boundary-layer of liquid of actual measurement or according to fixingApart from interval, at the one side contacting with the liquid cross mark processed of cover plate 23. The thickness of cover plate 23Larger, stronger to the absorption of optical signal, thus weaken from the optical signal of sample cell 20 outgoingIntensity, be not easy to the refractive index of Obtaining Accurate liquid boundary-layer. According to a preferred embodiment of the invention,The thickness of cover plate 23 is no more than 3mm. If the thickness of cover plate 23 is too small, easy floating at liquidUnder power effect, swim in liquid upside, cannot eliminate surface tension of liquid completely to liquid thickness homogeneityImpact. Preferably, the thickness of cover plate 23 is 3mm. Preferably, for the ease of the biography of optical signalDefeated, the material of the base plate 21 of base plate 21 can be CaF₂Or BaF₂。

The incident ray that incident light source 10 produces near the liquid boundary-layer position of battery lead plate 22,Along the direction incident perpendicular to liquid levels and electric field. Measuring unit 40 is positioned at the light of incident rayLu Shang, obtains liquid External Electrical Field for receiving from optical signal the analysis of sample cell 20 outgoingThe transmissivity of adherent boundary-layer.

The incident ray that incident light source 10 produces likely comprises the clutter of its all band, and impact is measuredThe accuracy of result. In order to prevent the appearance of this problem, can be at incident light source 10 and sample cellChopper is set, using the wavelength signals that intercepts CF as incident light source between 20. Simultaneously at sampleTwo lock-in amplifiers are set between product groove 20 and measuring unit 40, on the one hand can eliminate chopperModulating frequency and ac frequency change the impact bringing, and can and amplify to go out from sample cell on the other handThe optical signal of penetrating, prevents because too weak and cannot obtain or cannot be accurate from the optical signal of sample cell outgoingAnalyze liquid refractivity. Fig. 5 shows according to measuring liquid in the preferred embodiment of the present invention adherent attachedThe flow chart of surface layer transmissivity, in figure, the incident ray that continuous spectrum light source 11 sends is through convergingThe rear formation monochromatic light of set of lenses 12, chopper 13 and monochromator 14, then by infrared surface focus lamp15 and infrared microscope 16 penetrate the liquid in sample cell after focusing on, from the optical signal of sample cell outgoingEnter Infrared Detectors 41, Infrared Detectors 41 enters according to the electric current of the light signal generating receivingOne-level lock-in amplifier 42, will enter secondary lock-in amplifier 43, warp again after corresponding electric current amplificationSecondary lock-in amplifier 43 is processed optical signal afterwards and is entered computer 44, and computer 44 is according to receptionOptical signal carry out analytical calculation, determine the transmissivity of the adherent boundary-layer of liquid. One-level lock-in amplifierThe impact that 42 modulating frequencies that are mainly used to eliminate chopper 13 are brought, secondary lock-in amplifier 43Be mainly used in eliminating ac frequency and change the impact bringing to measurement. By these two lock-in amplifiersEffect, can extract the measured signal of CF, get rid of noise signal, and strengthen input meterThe optical signal of calculation machine is to be convenient for measuring. Chopper controller 60 in figure for control chopper 13,One-level lock-in amplifier 42 and secondary lock-in amplifier 43.

Because electric field is little on the impact of liquid refractivity, and the thickness of liquid boundary-layer is less, forThe transmissivity of the adherent boundary-layer of liquid under Measurement accuracy External Electrical Field, must ensure measurement mechanism toolThere is higher certainty of measurement. According to a preferred embodiment of the invention, the depth of parallelism between two battery lead plates,And the depth of parallelism between cover plate and base plate is not more than 0.5%; The processing roughness of battery lead plate is less thanRa1.6; The fineness of base plate and cover plate processing is 60-40,3, aperture, and the depth of parallelism is not more than 0.5%,In base plate and cover plate without bubble, without scattering particles.

Also can be for measuring the transmissivity of liquid under non-electric field effect according to measuring method of the present invention.When the thickness of testing liquid hour, adopt conventional measuring system to be difficult to ensure the liquid level of testing liquidHighly consistent. By adopting sample cell of the present invention, thickness that can Obtaining Accurate testing liquid, andAnd can avoid the uneven problem of liquid level causing due to surface tension of liquid. Based on this, the present invention also canBe applied to gradient liquid (thering is the liquid of non-homogeneous transmissivity) transmissivity measurement, have denseThe field such as the measurement of diverse location place fluid transmittance in the poor solution of degree. The biofilm thickness of organismLess, and biomembranous both sides and inside exist a large amount of biochemical reactions. Due to the present inventionCan measure the fluid transmittance within the scope of miniature scale, therefore also can be with being applied to biofilm thicknessThe fields such as the ir transmissivity measurement of inverting and optical characteristic measurement thereof, dissimilar cell.

Although with reference to illustrative embodiments, invention has been described, should be appreciated that the present inventionBe not limited in literary composition the detailed description of the invention of describing in detail and illustrating, limit not departing from claimsIn the situation of fixed scope, those skilled in the art can make various changing to described illustrative embodimentsBecome.

Claims (10)

1. a measuring method for the adherent boundary-layer transmissivity of liquid under External Electrical Field, its feature existsIn comprising:

S1, according to the liquid thickness in electric-field intensity and incident ray direction, determine the adherent of liquidBoundary-layer region, and determine the incident of incident ray on sample cell according to described adherent boundary-layer regionPosition;

S2, make incident ray along the direction perpendicular to liquid levels and electric field, from described incoming positionIncident, obtains the incident intensity of incident ray and incident ray and sees through first after empty sample cellTransmitted intensity, determines that according to incident intensity and the first transmitted intensity the extinction of empty sample cell is strongDegree;

S3, make incident ray along the direction perpendicular to liquid levels and electric field, from described incoming positionIncident, the incident intensity and the incident ray that obtain incident ray see through the sample that testing liquid is housedThe second transmitted intensity after groove;

S4, photon absorbing intensity and the second transmitted intensity based on incident intensity, empty sample cell, determineThe transmissivity of testing liquid;

Wherein, sample cell comprises: base and two battery lead plates; The both sides of base raise up, and makeBase has matrix cross section; The two ends of base arrange respectively a battery lead plate; Battery lead plate isType boss structure, comprising: perpendicular to the battery lead plate main body of base be arranged on battery lead plate main body sideHorizontal projection; Horizontal projection coordinates with the matrix cavity shape of base end; Two battery lead plates respectively withThe both positive and negative polarity of power supply connects, for generation of electric field.

2. measuring method as claimed in claim 1, wherein, horizontal projection in the horizontal directionExtension elongation l meets following relation:

l＝1.25/d

$d=\sqrt{\frac{\mathrm{\μ}}{7\mathrm{\ρ}}+\frac{L}{0.01E^{3.5}}}$

In formula, m is the viscosity of liquid in sample cell, and unit is: Pas; R is liquid in sample cellDensity, unit is: g/cm³; L is two distances between battery lead plate, and unit is: cm; E isElectric-field intensity, unit is: v/m.

3. measuring method as claimed in claim 1, wherein, sample cell also comprises cover plate; ElectrodeThe horizontal projection of plate thickness in vertical direction equates with the height of projection of chassis side, horizontal projectionUpper surface and the upper surface of chassis side projection in same plane, it is protruding that cover plate covers chassis sideRise and described horizontal projection on.

4. measuring method as claimed in claim 3, wherein, the contacting with liquid of described cover plateOne side chromium plating is also provided with focusing mark, the benchmark of adjusting as position when focusing on.

5. measuring method as claimed in claim 3, wherein, the thickness of cover plate is no more than 3mm.

6. measuring method as claimed in claim 3, wherein, the material of base plate and/or cover plate is:CaF₂Or BaF₂。

7. measuring method as claimed in claim 1, wherein, the titanium that battery lead plate is surperficial platinum plating orNiobium.

8. measuring method as claimed in claim 1, wherein, the depth of parallelism between two battery lead plates,And the depth of parallelism between cover plate and base plate is not more than 0.5%; The processing roughness of battery lead plate is less thanRa1.6; The fineness of base plate and cover plate processing is 60-40,3, aperture, and the depth of parallelism is not more than 0.5%,In base plate and cover plate without bubble, without scattering particles.

9. measuring method as claimed in claim 1, wherein, horizontal projection in vertical directionThickness is no more than 3mm.

10. measuring method as claimed in claim 1, further comprises:

Between incident light source and sample cell, chopper is set, the light producing from incident light source, interceptsThe wavelength signals of CF is as incident ray;

Two lock-in amplifiers are set between sample cell and measuring unit, are respectively used to eliminate chopperModulating frequency and ac frequency change the impact bringing, and to entering from the optical signal of sample cell outgoingRow amplifies to be processed.