Single-channel stability analyzer based on scattering method and transmission method

Abstract

The invention discloses a single-channel stability analyzer based on a scattering method and a transmission method, which comprises a light source mounted on a light path platform, a light path channel, a transmission light detector, a back scattering light detector, a control unit of the back scattering light detector, a round sample bottle and a lifting mechanism for integrally lifting the light path platform, incident light emitted by the light source irradiates a sample bottle containing a sample through the light path channel, the change of the sample along with time or temperature is detected by detecting scattered light signals and transmitted light signals passing through the sample bottle, then the instability change of the sample along with space distribution, time and temperature is obtained, and a quantitative instability index Ius is given. Sample layering thickness, particle migration speed and sample particle size information. According to the invention, a plurality of single-channel hosts can be controlled by a set of software system installed in a computer, so that a plurality of samples can be tested at the same time.

Description

Technical Field

[0001] The invention relates to the field of testing and control, and in particular to a single-channel stability analyzer based on a scattering method and a transmission method. Background Art

[0002] The stability analyzer is used to measure the separation, sedimentation, suspension or clarification, flotation, aggregation, coagulation or product storage period and particle size distribution of samples. It is widely used in the research and development of suspension formulations, emulsions and foams, detection and improvement of unstable suspensions, prediction of product storage stability, monitoring of centrifugal acceleration separation processes, determination and control of the optimal amount of sedimentation agents, and quality control for various industries, such as industrial oils, muds, pharmaceuticals, cosmetics, foods, coatings, dyes, chemical suspensions, CMP polishing fluids, nano-scale soft particles, colloids, polymer suspensions, agricultural products, lubricants, wastewater treatment, mud separation, pulp and papermaking industries, etc.

[0003] Product stability research is one of the urgent needs of scientific research, especially industrial users. For a long time, the research on stability has been based on qualitative empirical observations, and there has always been a lack of a quantitative, fast, accurate, non-invasive, and high-throughput method. Summary of the invention

[0004] In order to solve the above problems, the present invention discloses a single-channel stability analyzer based on scattering method and transmission method.

[0005] The specific technical solutions are as follows:

[0006] A single-channel stability analyzer based on scattering method and transmission method, comprising a lifting mechanism, an optical path platform, a sample testing area, a light source installed on the optical path platform, an optical path channel, a transmission light detector, a backscattered light detector and a sample bottle;

[0007] The light source, the transmitted light detector and the backscattered light detector are arranged in the optical path platform;

[0008] The sample bottle is placed vertically, and the incident light emitted by the light source is irradiated onto the sample bottle containing the sample through the optical path channel. The change of the sample over time or temperature is detected by detecting the scattered light signal and the transmitted light signal passing through the sample bottle, thereby analyzing the stability of the sample;

[0009] A touch LCD screen is set on the analyzer housing to display the instrument status and set the internal temperature;

[0010] The optical path platform comprises a light source and an outgoing light channel for limiting the outgoing angle of the light source, a transmitted light detector and a transmitted light channel for limiting the incident angle of the transmitted light, a backscattered light detector and a backscattered light channel for limiting the incidence of the backscattered light;

[0011] The lifting mechanism comprises a motor arranged on a bottom plate, the output end of the motor is connected to a bearing through a synchronous belt, wherein the bearing has a lead screw;

[0012] The optical path platform is connected to the bearing and is lifted and lowered by rotating the bearing to detect the transmission and backscattering signals of samples at different heights;

[0013] The sample testing area includes a sample bottle holder for holding a sample bottle, wherein a typical sample bottle for testing is cylindrical and is used to hold a sample. After the sample bottle is placed in the sample bottle holder, its position is fixed and cannot be moved. During the test, the sample remains stationary, and the device does not apply other forces to the sample, which is a non-invasive test;

[0014] The support column is arranged on the bottom plate of the analyzer, and is used for supporting the lead screw and fixing the sample test area; when the light source is turned on, the signal received by the transmitted light detector and the signal received by the backscattered light detector are respectively transmitted to the data acquisition card, and the data acquisition card transmits the received signal to the microprocessor, and the microprocessor transmits the final signal to the PC.

[0015] The single-channel stability analyzer based on scattering and transmission methods has a preferred solution in which the setting direction of the transmission light detector takes into account the refraction of the light beam through the circular sample bottle, and the main light spot of the light beam will not deviate from the detection range of the transmission light detector after passing through the sample bottle under the condition of water as the medium. The transmission light detector is used to detect samples with weak scattering. Such samples are characterized by low turbidity and strong transmission signal, that is, the transmission light signal is higher than 0.2%, and the transmission signal is used to calculate the sample instability index.

[0016] The single-channel stability analyzer based on scattering and transmission methods has a preferred solution in which the backscattered light detector is arranged in a direction to detect the scattered signal of the sample near the bottle wall on the back side of the sample bottle. The backscattered light detector is used to detect samples with strong scattering. The scattering volume corresponding to the backscattered light detector is close to the bottle wall of the sample bottle. Such samples are characterized by high turbidity and weak transmission signal, that is, the transmission light signal is lower than 0.2%, and the scattered signal is used to calculate the sample instability index.

[0017] The single-channel stability analyzer based on scattering and transmission methods, the preferred solution is that the motor driven lifting mechanism controlled by the microprocessor moves the optical path platform up and down, with 20 μm in the vertical direction as a detection point, to detect the transmission and backscattering signals of samples at different positions in the vertically placed sample bottle, and simultaneously generate the curve of the backscattering and transmission signals depending on the detection time and the height position of the sample bottle. Each time the optical path platform performs detection, the zero point position is confirmed by the photoelectric switch during its movement, and multiple movements will not cause cumulative errors.

[0018] The preferred embodiment of the single-channel stability analyzer based on scattering and transmission methods is that the intrinsic reasons for sample changes can be qualitatively understood according to the changes of the transmitted light or scattered light signal of the sample over time or temperature. For example, the sedimentation and floating process of the sample will bring about opposite change trends of the signals at the top and bottom of the sample bottle; the increase or decrease of the particle size of the sample will bring about the increase or decrease of the overall signal; and the phase separation process of the sample will bring about a sudden change of the signal at the interface between the two phases.

[0019] The single-channel stability analyzer based on the scattering method and the transmission method has a preferred embodiment in which the analyzer has a temperature control capability and can control the temperature of the sample within the range of room temperature + 5°C to 80°C, and the test temperature can be set through software or the LCD function keys on the front panel of the instrument.

[0020] The single-channel stability analyzer based on the scattering method and the transmission method has a preferred embodiment in which the analyzer has the ability to programmatically change the sample temperature, and can heat or cool the sample within a set temperature range, at a set temperature interval and under constant temperature time conditions, and programmatically perform signal detection during the temperature change process to examine the impact of temperature on the sample.

[0021] The single-channel stability analyzer based on the scattering method and the transmission method, the preferred solution is to control up to 10 single-channel hosts through a software system installed in a computer to simultaneously test up to 10 samples, and each single-channel host can perform independent testing according to a set standardized operating procedure SOP.

[0022] The single-channel stability analyzer based on the scattering method and the transmission method, its preferred solution is that a three-color indicator light strip with blue, green and red colors is set on the device casing, and the blue color is always on to indicate that the instrument is powered on; the green color is always on to indicate that the software is connected, and the green flashing indicates the start of the test; the green and red color flash at intervals to indicate a high temperature test state exceeding 40°C, the red color is always on to indicate a high temperature standby state exceeding 40°C, and the red color flashes quickly to indicate that the instrument has failed.

[0023] Beneficial Effects

[0024] 1. The high-sensitivity detection optical path of the present invention, which combines the scattering method and the transmission method, can provide a detection capability 100 times higher than the recognition capability of the naked eye, and the detection is faster and more accurate;

[0025] 2. You can use I US The instability index provides quantitative sample change information;

[0026] 3. The intrinsic reasons that lead to sample changes can be qualitatively obtained through the original transmission or backscattering spectrum, such as particle size change, sedimentation, floating, phase change, etc.;

[0027] 4. The sample can be heated or cooled within a set temperature range, at a set temperature interval and constant temperature time, and signal detection can be performed in a programmed manner during the process to examine the effect of temperature on the sample;

[0028] 5. The software can control up to 10 detection devices at the same time and detect 10 samples at the same time, with high detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The schematic diagram of a single-channel stability analyzer based on scattering and transmission methods is shown in FIG.

[0030] Figure 2 It is a schematic diagram of the external structure of a single-channel stability analyzer based on scattering method and transmission method;

[0031] Figure 3 It is a schematic diagram of the internal structure of a single-channel stability analyzer based on scattering method and transmission method;

[0032] Figure 4 It is a schematic diagram of the transmitted light detection in the present invention;

[0033] Figure 5 This is a schematic diagram of backscattered light detection in the present invention;

[0034] Figure 6 It is a test logic flow chart of the present invention;

[0035] Figure 7 The original signal and instability index I involved in the present invention US Schematic diagram of curve generation;

[0036] Figure 8 A schematic diagram is generated for the migration rates involved in the present invention.

[0037] In the figure: 1 is a lifting platform, 2 is a liquid crystal screen, 3 is an indicator light strip, 4 is an optical path platform, 5 is a sample bottle, 6 is a support column, 7 is a bearing, 8 is a sample bottle fixing seat, 9 is a scattering volume, 10 is a synchronous belt, 11 is a motor, 12 is a light source, 13 is a backscattered light detector, 14 is a backscattered light channel, 15 is a sample, 16 is a transmitted light detector, 17 is a transmitted light channel, 18 is a light beam, and 19 is an outgoing light channel. DETAILED DESCRIPTION

[0038] The following is combined with Figure 1-8Specifically describing the present invention, a single-channel stability analyzer based on scattering method and transmission method comprises a lifting mechanism, an optical path platform, a sample testing area, a light source mounted on the optical path platform, an optical path channel, a transmission light detector, a backscattered light detector and a sample bottle;

[0039] The light source 12, the transmitted light detector 16, and the backscattered light detector 13 are arranged in the optical path platform 4; the sample bottle 5 is placed vertically, and the incident light emitted by the light source 12 is irradiated onto the sample bottle 5 containing the sample 15 through the optical path channel, and the change of the sample 15 with time or temperature is detected by detecting the scattered light signal and the transmitted light signal passing through the sample bottle 5, thereby analyzing the stability of the sample;

[0040] A touch LCD screen 2 and an indicator light 3 are provided on the analyzer housing to display the instrument status and set the internal temperature;

[0041] The optical path platform 4 includes a light source 12 and an outgoing light channel 19 for limiting the outgoing angle of the light source, a transmitted light detector 16 and a transmitted light channel 17 for limiting the incident angle of the transmitted light, a backscattered light detector 13 and a backscattered light channel 14 for limiting the incidence of the backscattered light;

[0042] The lifting mechanism comprises a motor 11 arranged on the bottom plate, the output end of the motor 11 is connected to the bearing 7 through a synchronous belt 10, wherein the bearing 7 has a lead screw;

[0043] The optical path platform 4 is connected to the bearing 7 and is raised and lowered by rotating the bearing 7 to detect the transmission and backscattering signals of samples at different height positions;

[0044] The sample testing area includes a sample bottle holder 8 for holding a sample bottle 5, wherein a typical sample bottle 5 for testing is cylindrical and is used to hold a sample 15. After the sample bottle 5 is placed in the sample bottle holder 8, its position is fixed and cannot be moved. During the test, the sample remains stationary, and the device does not apply other forces to the sample, which is a non-invasive test;

[0045] The support column 6 is used to support the lead screw and fix the sample test area.

[0046] When the light source is turned on, the signal received by the transmitted light detector 16 and the signal received by the backscattered light detector 13 are respectively transmitted to the data acquisition card, and the data acquisition card transmits the received signals to the microprocessor, and the microprocessor transmits the final signal to the PC.

[0047] The setting direction of the transmitted light detector 16 takes into account the refraction of the light beam 18 through the circular sample bottle 5. Under the condition of water as the medium, the main light spot of the light beam will not deviate from the detection range of the transmitted light detector 16 after passing through the sample bottle. The transmitted light detector 16 is used to detect samples with weak scattering. Such samples are characterized by low turbidity and strong transmission signals, that is, the transmission light signal is higher than 0.2%, and the transmission signal is used to calculate the sample instability index.

[0048] The backscattered light detector 13 is set in a direction to detect the scattered signal of the sample near the bottle wall on the back side of the sample bottle 5. The backscattered light detector 13 is used to detect samples with strong scattering. The backscattered light detector corresponds to a scattering volume 9 close to the bottle wall of the sample bottle. The backscattered light detector 13 corresponds to a scattering volume close to the bottle wall of the sample bottle 5. Such samples are characterized by high turbidity and weak transmission signal, that is, the transmission light signal is lower than 0.2%, that is, the scattered signal is used to calculate the sample instability index.

[0049] The motor driven lifting mechanism controlled by the microprocessor moves the optical path platform 4 up and down, with 20 μm in the vertical direction as a detection point, to detect the transmission and backscattering signals of samples at different positions in the vertically placed sample bottle 5, and simultaneously generate a curve of the backscattering and transmission signals depending on the detection time and the height position of the sample bottle. Each time the optical path platform 4 performs a detection, the zero point position is confirmed by the photoelectric switch during its movement, and multiple movements will not cause cumulative errors.

[0050] The intrinsic reasons for the changes in the sample 15 transmitted light or scattered light signals over time or temperature can be qualitatively understood. For example, the sedimentation and floating process of the sample will bring about opposite changes in the signals at the top and bottom of the sample bottle; the increase or decrease in the particle size of the sample will bring about an increase or decrease in the overall signal; and the phase separation process of the sample will bring about a sudden change in the signal at the interface between the two phases.

[0051] The analyzer has temperature control capability and can control the temperature of samples in the range of room temperature + 5°C to 80°C, and the test temperature can be set through software or the LCD function keys on the front panel of the instrument.

[0052] The analyzer has the ability to programmatically change the sample temperature. It can heat or cool the sample within a set temperature range, at a set temperature interval and constant temperature time. In this process, it can programmatically detect signals to examine the impact of temperature on the sample. Through a software system installed in the computer to control multiple single-channel hosts, it can control up to 10 detection devices at the same time and detect 10 samples at the same time. Each single-channel host can be independently tested according to the set standardized operating procedure SOP.

[0053] A three-color indicator light strip 3 with blue, green and red colors is provided on the device casing. The blue color is constantly on to indicate that the instrument is powered on; the green color is constantly on to indicate that the software is connected, and the green color flashes to indicate the start of the test; the green and red colors flash alternately to indicate a high temperature test state exceeding 40°C, the red color is constantly on to indicate a high temperature standby state exceeding 40°C, and the red color flashes quickly to indicate that the instrument has a fault.

[0054] The detection process of the present invention comprises the following steps:

[0055] Step 1: Set the test parameters of the sample in the software, including the number of scans, scanning step distance, test temperature, sample constant temperature time, etc.;

[0056] Step 2: Turn on the light source 12, and the motor moves the optical path platform 4 so that the optical path platform is located at the bottom of the sample bottle 5 containing the sample;

[0057] Step 3: Determine whether the set start scanning time has been reached. If so, start a scan;

[0058] Step 4: The transmitted light signal and the backscattered light signal are collected by the transmitted light detector 16 and the backscattered light detector 13 respectively, and are saved together with the real time of the test into the data acquisition card;

[0059] Step 5: The microprocessor controls the optical path stage to move upward in the vertical direction according to the stepping distance set in the software;

[0060] Step 6: Determine whether the moving position reaches the specified position;

[0061] Step 7: If it is the specified position, proceed to the steps described in step 4;

[0062] Step 8: Repeat the operations from step 3 to step 7 until the platform moves to the top position of the sample bottle set in the software, and stop the test;

[0063] Step 9: Determine whether the total number of scans has been reached. If so, stop scanning. If not, continue with steps 3 to 8 until all the set number of scans have been completed.

[0064] In the present invention, the collected signals are processed by software in a PC, and the software processing process includes the following steps:

[0065] Step 1: Set the distance between the bottom of the bottle and the meniscus according to the spectrum, and then select the effective analysis range.

[0066] Step 2: Select a spectral curve and set it as the reference curve.

[0067] Step 3: Compare all curves after the reference curve with the reference curve to obtain a set of trend curves of signal changes over time at different test times. By calculating this curve, the instability index Ius is obtained.

[0068]

[0069] Where: In(h) is the signal intensity at position h, n is the nth scan, and h is the height of the scan position.

[0070] Step 4: For signal data with obvious peak characteristics, you can set the peak left and right positions and height thresholds to calculate the peak thickness, and then calculate the migration rate by the ratio of peak thickness to time.

[0071] Step 5: The average hydrodynamic particle size of the sample can be calculated using the migration rate and hydrodynamic parameters.

[0072]

[0073] Where: V is the migration rate, ρ p is the particle density, ρ c is the medium density, d is the average particle diameter, g is the gravity intensity, η is the medium viscosity, and Φ is the volume concentration.

[0074] Step 6: The optical average particle size can be calculated using the Lambert-Beer law.

[0075]

[0076] Where T 0 is the incident light intensity, T is the light intensity detected by the transmission detector, r i is half of the inner diameter of the sample bottle, l is the mean free path of photons, d is the particle size of the sample, Φ is the volume fraction, and Qs is obtained from the Mie theory.

Claims

1. A single-channel stability analyzer based on scattering method and transmission method, characterized in that: It includes a lifting mechanism, an optical path platform, a sample testing area, a light source installed on the optical path platform, an optical path channel, a transmitted light detector, a backscattered light detector and a sample bottle; The light source, the transmitted light detector and the backscattered light detector are arranged in the optical path platform; The sample bottle is placed vertically, and the incident light emitted by the light source is irradiated onto the sample bottle containing the sample through the optical path channel. The change of the sample over time or temperature is detected by detecting the scattered light signal and the transmitted light signal passing through the sample bottle, thereby analyzing the stability of the sample; A touch LCD screen is set on the analyzer housing to display the instrument status and set the internal temperature; The optical path platform comprises a light source and an outgoing light channel for limiting the outgoing angle of the light source, a transmitted light detector and a transmitted light channel for limiting the incident angle of the transmitted light, a backscattered light detector and a backscattered light channel for limiting the incidence of the backscattered light; The lifting mechanism comprises a motor arranged on the bottom plate of the analyzer, the output end of the motor is connected to a bearing through a synchronous belt, wherein the bearing has a lead screw; The optical path platform is connected to the bearing and is lifted and lowered by rotating the bearing to detect the transmission and backscattering signals of samples at different heights; The sample testing area includes a sample bottle holder for holding a sample bottle, wherein a typical sample bottle for testing is cylindrical and is used to hold a sample. After the sample bottle is placed in the sample bottle holder, its position is fixed and cannot be moved. During the test, the sample remains stationary, and the device does not apply other forces to the sample, which is a non-invasive test; The support column is arranged on the bottom plate of the analyzer and is used to support the lead screw and fix the sample test area; When the light source is turned on, the signal received by the transmitted light detector and the signal received by the backscattered light detector are respectively transmitted to the data acquisition card, and the data acquisition card transmits the received signals to the microprocessor, and the microprocessor transmits the final signal to the PC.

2. A single-channel stability analyzer based on scattering method and transmission method according to claim 1, characterized in that: The arrangement direction of the transmitted light detector in the optical path platform takes into account the refraction of the light beam through the circular sample bottle. Under the condition of water as the medium, the main light spot of the light beam will not deviate from the detection range of the transmitted light detector after passing through the sample bottle; the transmitted light detector is used to detect samples with weak scattering. The characteristics of such samples are low turbidity and strong transmission signal, that is, the transmitted light signal is higher than 0.2%, and the transmission signal is used to calculate the sample instability index.

3. A single-channel stability analyzer based on scattering method and transmission method according to claim 1, characterized in that , the backscattered light detector is arranged in the optical path platform in a direction to detect the scattered signal of the sample on the back side of the sample bottle close to the bottle wall; The backscatter detector is used to detect samples with strong scattering. The corresponding scattering volume of the backscatter detector is close to the wall of the sample bottle. This type of sample is characterized by high turbidity and weak transmission signal, that is, the transmission light signal is lower than 0.2%, and the scattering signal is used to calculate the sample instability index.

4. A single-channel stability analyzer based on scattering method and transmission method according to claim 1, characterized in that: A motor-driven lifting mechanism controlled by a microprocessor is used to move the optical path platform up and down. The transmission and backscattering signals of samples at different positions in a vertically placed sample bottle are detected with 20μm in the vertical direction as a detection point, and a curve of the backscattered and transmission signals depending on the detection time and the height position of the sample bottle is generated at the same time.

5. A single-channel stability analyzer based on scattering method and transmission method according to claim 1, characterized in that: The stable analyzer has the ability to control temperature. It can control the temperature of the sample in the range of room temperature + 5℃ to 80℃, and the test temperature can be set through the software or the LCD function keys on the front panel of the instrument.

6. A single-channel stability analyzer based on scattering method and transmission method according to claim 1, characterized in that: The stable analyzer has the ability to programmatically change the sample temperature. It can heat or cool the sample within a set temperature range, at a set temperature interval and constant temperature time. During the temperature change process, it can programmatically perform signal detection to examine the impact of temperature on the sample.

7. A single-channel stability analyzer based on scattering method and transmission method according to claim 1, characterized in that: A software system installed in a computer controls up to 10 single-channel hosts to test up to 10 samples simultaneously. Each single-channel host can perform independent testing according to the set standardized operating procedure SOP.

8. A single-channel stability analyzer based on scattering method and transmission method according to claim 1, characterized in that: The optical signal obtained from the test is transmitted to the PC, and the software in the PC processes and calculates the signal according to the logical steps of the software processing process, thereby obtaining the instability index, sample layer thickness, particle migration speed and sample particle size information.

9. A single-channel stability analyzer based on scattering method and transmission method according to claim 1, characterized in that: A three-color indicator light strip with blue, green and red colors is set on the device housing, and the blue light is always on to indicate that the instrument is powered on; The green light always indicates the software is connected, and the green light flashes to indicate the start of the test. The green and red light flash alternately to indicate a high temperature test state exceeding 40°C, the red light always indicates a high temperature standby state exceeding 40°C, and the red light flashes quickly to indicate an instrument failure.

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