AU2020104424A4 - A method and equipment for measuring absorption coefficient of liquid - Google Patents
A method and equipment for measuring absorption coefficient of liquid Download PDFInfo
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- AU2020104424A4 AU2020104424A4 AU2020104424A AU2020104424A AU2020104424A4 AU 2020104424 A4 AU2020104424 A4 AU 2020104424A4 AU 2020104424 A AU2020104424 A AU 2020104424A AU 2020104424 A AU2020104424 A AU 2020104424A AU 2020104424 A4 AU2020104424 A4 AU 2020104424A4
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/314—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry with comparison of measurements at specific and non-specific wavelengths
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
- G01N21/03—Cuvette constructions
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/314—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry with comparison of measurements at specific and non-specific wavelengths
- G01N2021/3155—Measuring in two spectral ranges, e.g. UV and visible
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Abstract
The invention provides a method and equipment for measuring absorption coefficient of liquid.
Wherein, the measuring equipment is composed of a light source unit, a sample cell unit, a
detection unit, a position control unit, a signal synchronization and data acquisition unit and an
instrument shell. Specifically, the sample cell unit is fixedly connected with a light source unit
on the left side and a detection unit on the right side. And they are all placed in the instrument
shell. The signal synchronization and data acquisition unit positioned outside the instrument
shell, is electrically connected with the light source unit and the detection unit respectively.
Further, the sample cell unit has a rectangular shell-like structure. The position control unit is
located in the sample cell unit and is in sliding connection with it. Besides, the left side of the
sample cell is provided with a first through hole and the position control unit is provided with
a second and a third through hole. The invention can avoid the large measurement error caused
by the reflectivity difference between the two interfaces inside the cuvette when measuring the
absorbance of liquid with high transmittance.
Description
A Method and Equipment for Measuring Absorption Coefficient of Liquid
The invention relates to the technical field of water body index determination, in
particular to a method and equipment for measuring absorption coefficient of liquid.
As an atomic or molecular absorption spectrum, ultraviolet-visible (UV-vis)
absorption spectrum is generated by energy level transition of electrons, owing to the
absorption of ultraviolet or visible light energy by molecules (or ions) in matter. In
addition to the electronic energy level transition, energy absorption by molecules (or
ions) will be accompanied by the vibration and rotation of molecules (or ions),
resulting in the transitions of vibration energy level and rotation energy level.
UV-vis absorption spectrum has a wide range of applications. It can be used for
quantitative analysis, qualitative analysis and structural analysis, as well as for the
analysis of inorganic and organic substances. Because of its simple and fast operation,
high sensitivity and accuracy, it has been widely used in many fields. For example, in
food production, in order to ensure the colour consistency of coloured drinks (such as
cola, fruit juice and tea drinks), the absorbance value can be measured by UV-vis
spectrophotometer in the visible light region to make the colour difference meet
product requirements. UV-vis spectrophotometry is the most widely used method for
determination of polysaccharide content in recent years. In the study of water quality,
the correlation and mathematical model between UV-vis absorption spectrum data
and some special substances in water are often established, and then the content of these special substances in water can be quantitatively acquired based on analysis of aforesaid UV-vis absorption spectrum data.
Dual-beam UV-vis absorption spectrometer is a commonly used instrument for
measuring absorption spectrum. The absorption of light by matter is selective,
therefore, the characteristics of the measured substance can be understood by its
absorption characteristics of light at a certain wavelength. Since different substances
have various molecules, atoms and molecular spatial structures, their absorption of
light energy will not be the same as well. Therefore, each substance has its own
unique and fixed absorption spectrum curve, and its content can be judged or
determined according to the absorbance at some characteristic wavelengths on the
absorption spectrum. Technicians who often use dual-beam UV-vis absorption
spectrometers know such a phenomenon which is contrary to common sense: when
measuring some liquid samples with high transmittance, the absorbance may appear
negative. Obviously, such measurement results need to be corrected.
The main defect of the prior art is as follows. Fig. 2 is the partial optical path diagram
of the dual-beam UV-vis absorption spectrometer, wherein PMT is a photomultiplier
tube, Ref is a reference cell cuvette, Sam is a sample cell cuvette, W is a diaphragm,
SEC and CH are combined semi-reflective mirror, M7 and M1O are plane mirrors,
and M6 and M9 are concave mirror. During baseline scanning, the cuvettes in
reference cell and sample cell are blank. Supposing the light intensity of the light path
passing through the sample and reference cells is the same, and accordingly, the
intensity of the last two beams to the photomultiplier tube is the same. Let the light passing through the reference cell be Io, and the light passing through the sample cell be I. During baseline scanning, the contents of the two sample cells are the same, and the baseline scanning value is always 0. It can be considered that the light passing through the sample cell is the same as that of the reference cell.
When the high transmittance liquid is put into the sample cell, the absorbance can be
expressed by the following formula:
A =-lg T = lg(0) (1) I Wherein, A is absorbance and T is transmittance (I/o). In the traditional dual-beam
spectrophotometer, the light intensity entering the sample cell is usually replaced by
the light intensity passing through the reference cell. If the light intensity passing
through the sample cell is greater than the light intensity passing through the reference
cell, the measured value of absorbance will be negative.
The new UV-2600 instrument of Shimadzu Instrument Company is taken as an
example. Entering the wavelength scanning interface and setting the scanning range
from 200 nm to 900 nm, scanning step size to 2 nm. Two clean quartz cuvettes are
placed in the sample and reference cells for baseline scanning. The obtained baseline
is a straight line with absorbance of 0 in the range of 200 nm-900 nm. After filling the
cuvette in the sample cell with deionized pure water, putting it into the sample cell
and the blank cuvette in the reference cell is unchanged, and then wavelength
scanning detection is carried out. The results are shown in Fig. 3 with wavelength as
abscissa and absorbance as ordinate. It can be found from Fig. 3 that the absorbance
of pure water appears negative at most wavelengths. Based on common sense, the attenuation of light under water is extremely serious, and even that under the purest filtered water cannot be ignored. Obviously, the light transmittance of air should be higher than that of water, even if it is pure deionized water. Therefore, the absorbance measurement result of water should be positive. However, on the premise that the experimental steps are correct and the instruments and supporting tools are working normally, the absorbance of the measured deionized pure water sample still appears negative.
The cuvette in the sample cell contains pure water, and the cuvette in the reference
cell contains air. The light transmittance of clean air should be greater than that of
pure water. How can the light intensity after passing through the sample cell be
greater than that after passing through the reference cell? If you consider the interface
reflection of the cuvette, you will find that this is the case.
When light passes through the cuvette of the sample cell or reference cell, it needs to
pass through four interfaces, as shown in Fig. 4. The two external interfaces (©and
@) of the cuvettes in sample cell and reference cell are consistent, so the reflection of
light on the interface is the same. However, due to the great difference of refractive
index of the contents, the reflectance at the two interfaces (3 and G)) of the sample
cell cuvette and the reference cell cuvette is very different. When the absorbance of
the contents in the sample cell cuvette is large, the difference of reflectivity between
the two interfaces can usually be ignored; however, when the light transmittance of
the contents in the sample cell cuvette is larger than that in reference cell cuvette, the
reflectivity difference between their two interfaces cannot be ignored.
When measuring, the content of reference cell cuvette is air, with refractive index
about 1. The content of sample cell cuvette is pure water, whose refractive index is
larger than that of air and closer to that of quartz. Therefore, the reflectivity of two
inner interfaces in sample cell cuvette is less than that of two inner interfaces in
reference cell cuvette, and the difference is even greater than that of pure water and
air, which leads to negative absorbance measurement of pure water. In order to get the
correct measurement results, the reflectivity difference between the two interfaces of
the sample cell must be considered. That is to say, when measuring the absorbance of
a liquid with high transmittance, such as purified water, it is necessary to consider the
influence of the reflectivity difference between the two interfaces inside the cuvette
and correct the measurement result. The correction method is usually cumbersome,
and there is a certain deviation in accuracy.
The instrument of the present invention is to solve above-mentioned problem
conveniently.
The purpose of the present invention is to provide a method and equipment for
measuring absorption coefficient of liquid to solve the problems existing in the prior
art. The measuring equipment and method can avoid the problem of large
measurement result error caused by the influence of the reflectivity difference
between the two interfaces inside the cuvette when measuring the absorbance of the
liquid with higher transmittance. Moreover, the measuring equipment and method are
simple and practical, with accurate measurement results.
In order to achieve above purpose, the invention provides the following scheme.
A measuring equipment of liquid absorption coefficient is composed of a light source
unit, a sample cell unit, a detection unit, a position control unit, a signal
synchronization and data acquisition unit and an instrument shell. Specifically, the left
side of the sample cell unit is fixedly connected with the light source unit, and its right
side is fixedly connected with the detection unit. And they are all placed in the
instrument shell. The signal synchronization and data acquisition unit positioned
outside the instrument shell, is electrically connected with the light source unit and the
detection unit respectively.
Further, the sample cell unit has a rectangular shell-like structure. The position control
unit is located in the sample cell unit and is in sliding connection with it. Besides, the
left side of the sample cell is provided with a first through hole and the position
control unit is provided with a second and a third through hole.
Preferably, the signal synchronization and data acquisition unit is used for adjusting
and controlling the light wavelength output by the light source unit and collecting
electric signals obtained by the detection unit, so as to know the light intensity
incident on the detector after being absorbed by liquid.
Preferably, the front plate and the back plate of sample cell are both provided with
main scales, and a graduated scale is lapped above the sample cell, specifically
located above the position control unit.
Further, a quartz transmitting collimation window is installed in the first through hole,
a condenser lens window is installed in the second through hole, and the third through
hole is located below the second through hole.
Specifically, the detection unit comprises optical fibres, which extend into the sample
cell unit and are connected with the condenser lens window.
Specifically, the lower plate, the front plate and the rear plate of the position control
unit are precisely polished and embedded with the bottom plate, front plate and back
plate of sample cell, respectively.
Moreover, the bulbs of the light source unit adopt xenon lamps and tungsten lamps,
and the light splitting part adopts prism light splitting or grating light splitting.
The measuring method of liquid absorption coefficient includes the following steps.
1) The general rule of light absorption by medium can be expressed by formula (2):
I= 10 - e- (2)
In the formula, Jo represents the intensity of incident light, and I represents the
intensity of incident light after traveling in the medium for x distance, In the dual
beam UV-vis absorption spectrometry, the intensity measured by reference laboratory
is used to replace the intensity incident on the sample cell, that is,
A = ax = -ln( ) (3) I Wherein, A is absorbance and a is absorption coefficient.
2) After the hot radiation with light intensity Io passes through the sample cell, the
light intensity detected by the detector can be described by the following formula:
I = (I0 - AI)- e-" (4)
In the formula, a is the light absorption coefficient of medium, x is the travel distance
of light in medium, AI is the light intensity lost by interface reflection and Io is the
incident light intensity of sample cell. Further, the light absorption coefficient a of
sample can be calculated by measuring the light intensity Ix at different lengths and x
positions of sample cell.
3) Light with a certain wavelength is selected to enter the sample cell, and the probes
of the position control unit and the optical fibre are close to the first through hole of
the sample cell, which is provided with a quartz transmitting collimation window, and
the intensity of the incident light is measured as Io. Injecting the liquid to be measured
into the sample cell and moving the probes of position control unit as well as the
optical fibre to the position x, thereby measuring the light intensity Ix. Recording
multiple groups of position x and corresponding light intensity values Ix. Then the
light absorption coefficient of the liquid to be measured at a certain wavelength is
calculated by formula (4).
The invention discloses the following technical effects.
1. In this invention, a light source unit, a sample cell unit, a position control unit, a
detection unit, a signal synchronization and data acquisition unit are arranged.
Further, a first through hole with a quartz transmitting collimation window inside is
arranged on the sample cell unit and a second through hole with a condenser lens
window is arranged on the position control unit. In this way, the light absorption
coefficient of the liquid can be calculated by measuring the transmitted light intensity
at different positions (i.e., the light intensity passing through liquids with different thicknesses), so that when measuring the absorbance of the liquid with higher transmittance, the problem of large measurement error caused by the difference of reflectivity between the two interfaces inside the cuvette can be avoided.
2. The main scale is set on the front plate and back plate of the sample cell, and the
graduated scale is lapped over the sample cell, specifically above the position control
unit. The main scale and graduated scale form a vernier scale, which can accurately
read the position of the position control unit board.
3. The position control unit is provided with a third through hole below the second
through hole, and the third through hole is a liquid flow window, which can keep the
sample liquid level unchanged before and after the position control unit moves.
In order to explain the embodiments of the present invention or the technical scheme
in the prior art more clearly, the figures needed in the embodiments will be briefly
introduced below. Obviously, the figures in the following description are only some
embodiments of the present invention, and for ordinary technicians in the field, other
figures can be obtained according to these without paying creative labour.
Figure 1 is a schematic structural diagram of the liquid absorption coefficient
measuring equipment in the present invention.
Figure 2 is the optical path diagram of UV-2600 UV-vis spectrometer.
Figure 3 is an absorption curve of pure water.
Figure 4 is a schematic diagram of light passing through a cuvette.
Figure 5 is a schematic structural diagram of a sample cell unit and a position control
unit.
Wherein, 1 is light source unit, 2 is sample cell unit, 3 is graduated scale, 4 is position
control unit, 5 is detection unit, 6 is signal synchronization and data acquisition unit, 7
is instrument shell, 8 is optical fibre, 201 is sample cell front plate, 202 is sample cell
back plate, 203 is first through hole, 401 is second through hole and 402 is third
through hole.
The technical scheme in the embodiments of the present invention will be described
clearly and completely with reference to figures in the embodiments of the present
invention. Obviously, the described embodiments are only part of the embodiments of
the present invention, not all of them. Based on the embodiments of the present
invention, all other embodiments obtained by ordinary technicians in the field without
creative labour belong to the protection scope of the present invention.
In order to make the above objects, features and advantages of the present invention
more obvious and easier to understand, the present invention will be further explained
in detail with reference to figures and specific embodiments.
Referring to Figs. 1-5, the invention provides a measuring equipment of liquid
absorption coefficient, which is composed of a light source unit (1), a sample cell unit
(2), a detection unit (5), a position control unit (4), a signal synchronization and data
acquisition unit (6) and an instrument shell (7). Specifically, the left side of the
sample cell unit (2) is fixedly connected with the light source unit (1), and its right side is fixedly connected with the detection unit (5). And they are all placed in the instrument shell (7). The signal synchronization and data acquisition unit (6) positioned outside the instrument shell (7), is electrically connected with the light source unit (1) and the detection unit (5) respectively.
Further, the sample cell unit (2) has a rectangular shell-like structure. The position
control unit (4) is located in the sample cell unit (2) and is in sliding connection with
it. Besides, the left side of the sample cell is provided with a first through hole (203)
and the position control unit (4) is provided with a second (401) and a third through
hole (402). Wherein, the second through hole (401) can be installed with an optical
fiber probe, and the third through hole (402) can keep the liquid balance on the left
and right sides of the position control unit (4);
The signal synchronization and data acquisition unit (6) is used for adjusting and
controlling the light wavelength output by the light source unit (1) and collecting
electric signals obtained by the detection unit (5), so as to know the light intensity
incident on the detector after being absorbed by liquid. The structure and principle of
the signal synchronization and data acquisition unit (6) belong to the available
technology, which is a common general knowledge of those technical personnel in the
art and will not be repeated here.
As a further optimization scheme, the front plate (201) and the back plate (202) of
sample cell are both provided with main scales, and a graduated scale (3) is lapped
above the sample cell, specifically located above the position control unit (4). The main scales and the graduated scale (3) constitute a vernier scale, which can accurately read out the position of the position control unit (4) board.
Preferably, a quartz transmitting collimation window is installed in the first through
hole (203), a condenser lens window is installed in the second through hole (401), and
the third through hole (402) is located below the second through hole (401). The third
through hole (402) is a liquid flow window, which can keep the liquid level of the
sample unchanged before and after the position control unit (4) moves.
As a preferred scheme, the detection unit (5) comprises optical fibres (8), which
extend into the sample cell unit (2) and are connected with the condenser lens
window. The detection unit (5) is similar to other light detection units, including
photodetectors such as photomultiplier tubes, avalanche photodiodes and other servo
circuits. Its internal structure and principle also belong to the available technology,
which is a common general knowledge of those technical personnel in the art and will
not be repeated here.
Further, the lower plate, the front plate and the rear plate of the position control unit
(4) are precisely polished and embedded with the bottom plate, front plate (201) and
back plate (202) of sample cell, respectively.
Furthermore, the bulbs of the light source unit (1) adopt xenon lamps and tungsten
lamps, and the light splitting part adopts prism light splitting or grating light splitting.
The measuring method of liquid absorption coefficient provided by the invention
includes the following steps.
1) The general rule of light absorption by medium can be expressed by formula (2):
I=10-e- (2)
In the formula, Jo represents the intensity of incident light, and I represents the
intensity of incident light after traveling in the medium for x distance, In the dual
beam UV-vis absorption spectrometry, the intensity measured by reference laboratory
is used to replace the intensity incident on the sample cell, that is,
A = ax = -ln( ) (3) I Wherein, A is absorbance and a is absorption coefficient.
2) After the hot radiation with light intensity Io passes through the sample cell, the
light intensity detected by the detector can be described by the following formula:
I = (I0 - AI)- e-" (4)
In the formula, a is the light absorption coefficient of medium, x is the travel distance
of light in medium, Al is the light intensity lost by interface reflection and Io is the
incident light intensity of sample cell. Further, the light absorption coefficient a of
sample can be calculated by measuring the light intensity Ix at different lengths and x
positions of sample cell.
3) Light with a certain wavelength is selected to enter the sample cell, and the probes
of the position control unit (4) and the optical fibre (8) are close to the first through
hole (203) of the sample cell, which is provided with a quartz transmitting collimation
window, and the intensity of the incident light is measured as Io. Injecting deionized
distilled water into the sample cell and moving the probes of position control unit (4)
as well as the optical fibre (8) to the position x, thereby measuring the light intensity
Ix.Then the light absorption coefficient of the liquid to be measured at a certain
wavelength is calculated by formula (4).
Light with a certain wavelength is selected to enter the sample cell, and the probes of
the position control unit (4) and the optical fibre (8) are close to the first through hole
(203) of the sample cell, which is provided with a quartz transmitting collimation
window, and the intensity of the incident light is measured as Io. Injecting deionized
distilled water into the sample cell and moving the probes of position control unit (4)
as well as the optical fiber (8) to the position x, thereby measuring the light intensity
Ix. Wherein, x is 1.0 cm, 2.0 cm, 5.0 cm and 10.0 cm, respectively. The measured data
are shown in Table 1.
Table 1. Light intensity at different positions detected by position control unit
Length of liquid Detected light intensity /Io /cm 380 nm 400 nm 500 nm 600 nm 700 nm 1 1.100 1.098 1.091 1.091 1.110 2 1.100 1.098 1.091 1.088 1.103 5 1.100 1.097 1.090 1.081 1.082 10 1.099 1.097 1.089 1.069 1.049 The optical absorption coefficients of liquids with different wavelengths are
calculated by formula (4), as shown in Table 2.
Table 2. Measured value of absorption coefficient of water
Wavelength /nm Absorption Standard coefficient /m- 1 deviation /m-1 380 0.010 0.004 400 0.011 0.005 500 0.022 0.003 600 0.224 0.004 700 0.628 0.004
In the description of the present invention, it should be understood that the orientation
or position relationship indicated by the terms of "longitudinal", "transverse",
"upper", "lower", "front", "rear", 'left", "right", "vertical", "horizontal", "top",
"bottom", "inner" and "outer", etc. is based on the orientation or position relationship
shown in figure, which is only for the convenience of describing the invention, rather
than indicating or implying that the device or element referred to must have a specific
orientation, be constructed and operated in a specific orientation, therefore, it cannot
be understood as a limitation of the invention.
The above embodiments only describe the preferred mode of the invention, but do not
limit the scope of the invention. On the premise of not departing from the design spirit
of the invention, various modifications and improvements made by ordinary
technicians in the field to the technical scheme of the invention shall fall within the
protection scope determined by the claims of the invention.
Claims (7)
1. A measuring equipment of liquid absorption coefficient, characterized by comprising a
light source unit (1), a sample cell unit (2), a detection unit (5), a position control unit (4),
a signal synchronization and data acquisition unit (6) and an instrument shell (7).
Specifically, the left side of the sample cell unit (2) is fixedly connected with the light
source unit (1), and its right side isfixedly connected with the detection unit (5). And
they are all placed in the instrument shell (7). The signal synchronization and data
acquisition unit (6) positioned outside the instrument shell (7), is electrically connected
with the light source unit (1) and the detection unit (5) respectively.
Further, the sample cell unit (2) has a rectangular shell-like structure. The position control
unit (4) is located in the sample cell unit (2) and is in sliding connection with it. Besides,
the left side of the sample cell is provided with a first through hole (203) and the position
control unit (4) is provided with a second (401) and a third through hole (402).
The signal synchronization and data acquisition unit (6) is used for adjusting and
controlling the light wavelength output by the light source unit (1) and collecting electric
signals obtained by the detection unit (5), so as to know the light intensity incident on the
detector after being absorbed by liquid.
2. The measuring equipment of liquid absorption coefficient according to Claim 1,
characterized in that the front plate (201) and the back plate (202) of sample cell are both
provided with main scales, and a graduated scale (3) is lapped above the sample cell,
specifically located above the position control unit (4).
3. The measuring equipment of liquid absorption coefficient according to Claim 1,
characterized in that a quartz transmitting collimation window is installed in the first through hole (203), a condenser lens window is installed in the second through hole
(401), and the third through hole (402) is located below the second through hole (401).
4. The measuring equipment of liquid absorption coefficient according to Claim 1,
characterized in that the detection unit (5) comprises optical fibres (8), which extend into
the sample cell unit (2) and are connected with the condenser lens window.
5. The measuring equipment of liquid absorption coefficient according to Claim 1,
characterized in that the lower plate, the front plate and the rear plate of the position
control unit (4) are precisely polished and embedded with the bottom plate, front plate
(201) and back plate (202) of sample cell, respectively.
6. The measuring equipment of liquid absorption coefficient according to Claim 1,
characterized in that the bulbs of the light source unit (1) adopt xenon lamps and tungsten
lamps, and the light splitting part adopts prism light splitting or grating light splitting.
7. The measuring method of liquid absorption coefficient according to Claim 1,
characterized by including the following steps:
1) The general rule of light absorption by medium can be expressed by formula (2):
I= 10 - e- (2)
In the formula, Jo represents the intensity of incident light, and I represents the intensity
of incident light after traveling in the medium for x distance, In the dual-beam UV-vis
absorption spectrometry, the intensity measured by reference laboratory is used to replace
the intensity incident on the sample cell, that is,
A = ax = -ln( ) (3) I
Wherein, Ais absorbance andcaxis absorption coefficient.
2) After the hot radiation with light intensity Io passes through the sample cell, the light
intensity detected by the detector can be described by the following formula:
I = (I0 - AI) - e-" (4)
In the formula, a is the light absorption coefficient of medium, x is the travel distance of
light in medium, Al is the light intensity lost by interface reflection and Io is the incident
light intensity of sample cell. Further, the light absorption coefficient a of sample can be
calculated by measuring the light intensity Ix at different lengths and x positions of
sample cell.
3) Light with a certain wavelength is selected to enter the sample cell, and the probes of
the position control unit (4) and the optical fibre (8) are close to the first through hole
(203) of the sample cell, which is provided with a quartz transmitting collimation
window, and the intensity of the incident light is measured as Io. Injecting the liquid to be
measured into the sample cell and moving the probes of position control unit (4) as well
as the optical fibre (8) to the position x, thereby measuring the light intensity Ix.
Recording multiple groups of position x and corresponding light intensity values Ix. Then
the light absorption coefficient of the liquid to be measured at a certain wavelength is
calculated by formula (4).
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010154150.3A CN111272683B (en) | 2020-03-07 | 2020-03-07 | Liquid absorption coefficient measuring device and measuring method |
| CN202010154150.3 | 2020-03-07 |
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| Publication Number | Publication Date |
|---|---|
| AU2020104424A4 true AU2020104424A4 (en) | 2021-06-03 |
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ID=70997689
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|---|---|---|---|
| AU2020104424A Ceased AU2020104424A4 (en) | 2020-03-07 | 2020-10-09 | A method and equipment for measuring absorption coefficient of liquid |
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| Country | Link |
|---|---|
| CN (1) | CN111272683B (en) |
| AU (1) | AU2020104424A4 (en) |
| WO (1) | WO2021179592A1 (en) |
| ZA (1) | ZA202105839B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114088666A (en) * | 2021-12-06 | 2022-02-25 | 上海易清智觉自动化科技有限公司 | Sand washing wastewater treatment detection device and method |
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| CN111272683B (en) * | 2020-03-07 | 2022-11-25 | 广东海洋大学 | Liquid absorption coefficient measuring device and measuring method |
| CN112763184B (en) * | 2020-12-23 | 2023-08-29 | 中国人民解放军国防科技大学 | Gain fiber absorption coefficient measuring device and method based on side scattered light detection |
| CN114397270A (en) * | 2021-12-06 | 2022-04-26 | 华中光电技术研究所（中国船舶重工集团公司第七一七研究所） | Water attenuation coefficient measuring system |
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| CN2093395U (en) * | 1991-06-25 | 1992-01-15 | 华祥荣 | Photoelectric type turbidimeter |
| CN101825564B (en) * | 2010-04-23 | 2012-07-04 | 浙江大学 | Optical detection method for continuously monitoring liquid concentration for a long time |
| CN101852727A (en) * | 2010-05-18 | 2010-10-06 | 浙江大学 | Optical detection method for continuously monitoring liquid concentration |
| US8475725B1 (en) * | 2012-08-21 | 2013-07-02 | East Coast Distribution, Inc. | System and method for liquid treatment |
| KR101472504B1 (en) * | 2013-03-06 | 2014-12-15 | 주식회사 메카시스 | Method of adjust the path length automatically for sample analysis, and it includes sample analysis method and its device. |
| CN103278450B (en) * | 2013-05-24 | 2017-12-12 | 徐姗 | Sample room for liquid absorption spectrum analysis |
| CN104833642B (en) * | 2015-05-20 | 2017-12-08 | 浙江科技学院 | A kind of adjustable liquid light transmission features measurement apparatus of light path |
| CN107202759A (en) * | 2017-06-26 | 2017-09-26 | 苏州奥特科然医疗科技有限公司 | A kind of solution absorbance auxiliary detection device and system |
| CN109374552B (en) * | 2018-11-23 | 2020-06-05 | 国家海洋局第二海洋研究所 | Water absorption coefficient measuring device based on segmented light path |
| CN209784178U (en) * | 2019-02-21 | 2019-12-13 | 德之馨（上海）有限公司 | Solution light absorption intensity detection device |
| CN111272683B (en) * | 2020-03-07 | 2022-11-25 | 广东海洋大学 | Liquid absorption coefficient measuring device and measuring method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114088666A (en) * | 2021-12-06 | 2022-02-25 | 上海易清智觉自动化科技有限公司 | Sand washing wastewater treatment detection device and method |
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| Publication number | Publication date |
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| CN111272683B (en) | 2022-11-25 |
| WO2021179592A1 (en) | 2021-09-16 |
| CN111272683A (en) | 2020-06-12 |
| ZA202105839B (en) | 2021-10-27 |
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