Multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation

Abstract

This invention discloses a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation, belonging to the field of micro calorimeter technology. It includes a support block, a furnace body positioned above the support block, an insulation layer arranged sequentially inside the furnace body, a heating cylinder inside the insulation layer, a homogenizing block inside the heating cylinder, and a calorimetric cavity inside the homogenizing block. A temperature sensor for the homogenizing block is positioned at the center of the calorimetric cavity. Several calorimetric channels are equidistantly arranged around the center of the homogenizing block inside the calorimetric cavity. These calorimetric channels are configured with either a multi-sample high-efficiency mode or a dual-channel high-precision mode. The invention also includes a dynamic temperature field compensation module and an intelligent anti-interference detection unit. This invention, employing the aforementioned multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation, combines high throughput, high precision, and strong anti-interference capabilities, meeting the dual requirements of scientific research for experimental efficiency and data reliability.

Description

Technical Field

[0001] This invention relates to the field of micro calorimetry technology, and in particular to a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation. Background Technology

[0002] Existing three-dimensional microcalorimeters are all single-channel structures, consisting of one sample channel and one reference channel, allowing only one sample to be placed in each experiment. However, various studies often require testing multiple sets of samples with different components, ratios, and quantities. When using existing single-channel instruments, samples must be tested sequentially, which not only multiplies the total time and the number of samples, significantly reducing research efficiency, but also introduces two scientific problems: First, even samples prepared in the same batch may undergo changes in properties (such as slight differences in reaction degree, water content, and component homogeneity) during storage due to the long sequential testing time, resulting in additional time-related deviations in the test results; second, the single-channel design makes it difficult to conduct parallel experiments under the same experimental conditions, leading to a lack of repeatability verification and an inability to effectively assess the stability and reliability of the data, which contradicts the basic requirements of repeatability and verifiability in scientific research. In existing single-channel three-dimensional micro calorimeters, multiple experiments are often conducted at different times, and the ambient temperature may deviate significantly. In addition, due to the characteristics of the instrument itself, there are always subtle differences at different time points. Especially for micro calorimeters, even extremely small differences may affect the quantitative measurement data.

[0003] To address the low efficiency of single-channel calorimeters, some existing technologies have proposed multi-channel calorimeters, but significant drawbacks remain: First, the multi-channel layout leads to severe thermal crosstalk between channels, with the thermal effects of samples in adjacent channels interfering with each other and reducing measurement accuracy. Second, the temperature field control accuracy is insufficient, with uneven temperature field distribution in the heating cylinder and homogenizing block, resulting in poor temperature consistency across different channels. Third, the anti-interference capability is weak; external factors such as ambient temperature fluctuations, humidity changes, air pressure fluctuations, and mechanical vibrations can easily interfere with heat flow and temperature signals, and existing technologies often rely on simple software-level corrections, making it difficult to completely eliminate common-mode noise. Fourth, the calibration process after mode switching is cumbersome; switching between high-efficiency and high-precision multi-channel modes requires complex recalibration, affecting experimental continuity and efficiency.

[0004] The above problems are particularly prominent when a large number of comparative experiments or high-throughput screenings are required: on the one hand, the total experimental time increases linearly with the number of samples, which reduces the research efficiency; on the other hand, since it is difficult to keep the testing conditions absolutely consistent, the repeatability and stability of the experimental data are greatly affected, and it is often necessary to increase the number of repeated experiments to verify the results, which further extends the research cycle and increases costs. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation, which has high throughput, high precision and strong anti-interference ability, and can meet the dual requirements of scientific research for experimental efficiency and data reliability.

[0006] To achieve the above objectives, the present invention provides a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation, comprising a support block, a furnace body disposed above the support block, a heat insulation layer disposed sequentially inside the furnace body, a heating cylinder disposed inside the heat insulation layer, a heat homogenizing block disposed inside the heating cylinder, a calorimetric cavity disposed inside the heat homogenizing block, a temperature sensor of the heat homogenizing block disposed at the center of the calorimetric cavity, and a plurality of calorimetric channels disposed at equal distances around the center of the heat homogenizing block inside the calorimetric cavity, wherein the distance between any two adjacent calorimetric channels is the same, a three-dimensional thermopile is fitted on the outer wall of each calorimetric channel, and the number of calorimetric channels is at least three, wherein the calorimetric channels are configured with a multi-sample high-efficiency mode or a dual-channel high-precision mode; It also includes a dynamic temperature field compensation module and an intelligent anti-interference detection unit; The dynamic temperature field compensation module includes an annular microchannel heat exchange structure, a phase change energy storage material, a micro electromagnetic valve, and a gradient thermal insulation coating. The annular microchannel is arranged inside the heat homogenizing block around the calorimetric channel. The phase change energy storage material is filled inside the annular microchannel. The micro electromagnetic valve is arranged between the calorimetric channel and the annular microchannel and is electrically connected to the PID algorithm control module of the main control circuit. The gradient thermal insulation coating is applied to the inner wall of the calorimetric channel. The intelligent anti-interference detection unit includes a multi-dimensional sensor array, an interference signal analysis chip, and an interference compensation algorithm module. The multi-dimensional sensor array is respectively set outside the furnace body and inside the calorimeter cavity. The interference signal analysis chip is integrated into the main control circuit, and the interference compensation algorithm module is set in the host computer PC software. The heat flow signal of the sample channel is connected in reverse series with the reference channel to obtain a differential signal, and interference correction is performed by the intelligent anti-interference detection unit.

[0007] Preferably, the phase change energy storage material is graphene composite paraffin, with a phase change temperature range of -196℃ to 200℃; the gradient thermal insulation coating consists of an inner nano-zirconia thermal insulation layer and an outer aluminum nitride thermal conductive layer, with the coating thickness at both ends of the axial direction being 1.5 times that of the middle region.

[0008] Preferably, the multi-dimensional sensor array includes an ambient temperature sensor, a humidity sensor, a barometric pressure sensor, and a micro-vibration sensor, with a sampling frequency ≥100Hz; the interference signal analysis chip has a built-in machine learning model for quantifying interference intensity and generating compensation parameters.

[0009] Preferably, the outer wall of the heating cylinder is uniformly wound with heating wires or heating strips, and the inner wall of the heating cylinder is provided with four heating cylinder temperature sensors, with the average value of the four temperature points used as the basis for temperature control; the top and bottom of the heating cylinder are respectively provided with an upper end cover and a lower end cover, and a heat insulation element is provided above the upper end cover.

[0010] Preferably, the three-dimensional thermopile, the uniform heating block temperature sensor, the heating cylinder temperature sensor, the heating wire or heating belt, the miniature electromagnetic valve, and the multi-dimensional sensor array are all connected to the main control circuit. The main control circuit includes a signal acquisition module, a signal amplification and filtering module, a data algorithm processing chip, an interference signal analysis chip, a data transmission module, and a PID algorithm control module. The main control circuit is connected to the host computer PC software.

[0011] Preferably, when the calorimetric channels are set to four, the multi-sample high-efficiency mode is to use three calorimetric channels as sample channel one, sample channel two and sample channel three respectively, and one as reference channel one; The dual-channel high-precision mode uses two calorimetric channels as sample channel four and sample channel five, and two as reference channel two and reference channel three, respectively. When switching between the two modes, a rapid calibration process of ≤30 seconds is automatically triggered.

[0012] Preferably, the multi-sample high-efficiency mode employs a channel consistency dynamic calibration method, which obtains the deviation coefficient of each channel through a standard reference sample and calibrates it in real time; the dual-channel high-precision mode employs a thermal crosstalk reverse cancellation algorithm, which outputs a reverse compensation electrical signal based on the temperature data of the annular microchannel.

[0013] Preferably, the heat flux calculation formulas for sample channel one, sample channel two, and sample channel three are as follows: ; ; ; in, These represent the actual differential heat fluxes of sample channel one, sample channel two, and sample channel three, respectively. These are the heat flows of sample channel one, sample channel two, and sample channel three, respectively. For the heat flow of reference channel one; All are channel deviation coefficients; This is the interference compensation correction value.

[0014] Preferably, the heat flux calculation formulas for sample channel four and sample channel five are as follows: ; ; in, These are the actual differential heat flows of sample channel four and sample channel five, respectively. These represent the heat flow of sample channel four and sample channel five, respectively. , These are the heat flows of reference channel two and reference channel three, respectively. , All values ​​are thermal crosstalk compensation values.

[0015] Preferably, the dual-mode adaptive calibration method for the three-dimensional micro calorimeter includes the following steps: S1, Dynamic calibration of channel consistency; S2, Thermal Crosstalk Reverse Cancellation Algorithm; S3, Quick Mode Switch Calibration; Step S1 obtains the deviation coefficient through a standard reference sample and calibrates it in real time; Step S2 cancels the interference of adjacent channels through reverse compensation electrical signals; Step S3 completes the adaptive adjustment of parameters within 30 seconds.

[0016] Therefore, the present invention employs the aforementioned multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation, and the technical effects are as follows: (1) Significantly improved measurement accuracy: In the dynamic temperature field compensation module, the phase change energy storage material of the annular microchannel can achieve dynamic thermal buffering across the entire temperature range (-196℃~200℃). Combined with the gradient thermal insulation coating, it blocks heat conduction between channels, making the thermal crosstalk error between channels ≤±0.002μW. The intelligent anti-interference detection unit captures external interference through a multi-dimensional sensor array, performs real-time compensation after quantitative analysis by a machine learning model, and achieves an interference signal attenuation rate ≥92%, a heat flow measurement error ≤±0.01μW, and a temperature measurement resolution improved to 0.001℃, which is more than 50% higher than the accuracy of existing multi-channel calorimeters.

[0017] (2) High experimental efficiency: The original application retains the core advantages of multi-channel. The four calorimetric channels can realize the high-efficiency mode of three samples + one reference. Multiple sets of samples can be tested simultaneously in a single experiment, which is more than 3 times more efficient than single-channel instruments. At the same time, an innovative fast mode switching calibration process is created. When switching between two working modes, an adaptive calibration of ≤30 seconds is automatically triggered without manual intervention. This solves the problem of cumbersome calibration after switching modes in the existing technology and ensures the continuity of experiments.

[0018] (3) Significantly enhanced anti-interference capability: Compared with the existing technology that relies solely on software differential correction for anti-interference, this invention acquires reverse series differential signals at the hardware level, combined with multi-dimensional interference capture and real-time compensation by the intelligent anti-interference detection unit. It can effectively suppress interference caused by ambient temperature fluctuations of ±5℃, humidity changes of ±20%, air pressure fluctuations of ±10kPa, and micro-vibration amplitudes of ≤5μm. The common-mode noise elimination rate is ≥95%, the data stability is greatly improved, and the thermal coefficient fluctuation is ≤±2% for 72 consecutive hours of operation.

[0019] (4) Wider range of applicable scenarios: The phase change energy storage material and gradient thermal insulation coating design of the dynamic temperature field compensation module enable the instrument to be stably applied to low temperature (-196℃) liquid nitrogen environment, room temperature and high temperature (200℃) reaction scenarios, covering a variety of temperature control requirements such as temperature scanning, constant temperature and cooling; the multi-channel layout and dual working mode can flexibly adapt to high-throughput screening (multi-sample high efficiency mode) and high-precision analysis (dual-channel high precision mode), meeting the experimental needs of different fields such as materials science, chemistry, and biology.

[0020] (5) Optimized ease of operation: The host computer PC software adds functions such as visualization of interference compensation parameters and automatic storage and retrieval of calibration data. Combined with the automated control of the main control circuit, it realizes full-process automation of experimental parameter setting, mode switching, data acquisition, analysis and calibration, reducing the professional threshold for operators. Each module adopts a modular design, which is convenient to maintain. The dynamic temperature field compensation module or intelligent anti-interference detection unit can be repaired and upgraded separately, extending the service life of the instrument.

[0021] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of an embodiment of a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to the present invention; Figure 2 This is a cross-sectional view of the furnace body of an embodiment of a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to the present invention; Figure 3 This is a cross-sectional view of the internal structure of the furnace body in an embodiment of a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to the present invention. Figure 4 This is a top cross-sectional view of the calorimetric channel of an embodiment of a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to the present invention. Figure 5 This is a logic block diagram of the main control circuit of an embodiment of a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to the present invention. Figure 6This is a temperature change curve of the sample channel and reference channel over time in Embodiment 1 of the multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation of the present invention. Figure 7 This is a graph showing the change in heat flow with temperature in the sample channel of a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to Embodiment 1 of the present invention.

[0023] Figure Labels 1. Support block; 2. Furnace body; 3. Top cover; 4. Top cover of the calorimeter channel; 5. Insulation layer; 6. Heating cylinder; 7. Heating cylinder temperature sensor; 8. Upper end cover; 9. Lower end cover; 10. Calorimeter chamber; 11. Uniform heating block; 12. Uniform heating block temperature sensor; 13. Calorimeter channel; 131. Calorimeter channel one; 132. Calorimeter channel two; 133. Calorimeter channel three; 134. Calorimeter channel four; 14. Three-dimensional thermopile; 15. Insulation element. Detailed Implementation

[0024] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0026] Example 1: like Figures 1-7 As shown, this embodiment provides a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation, which is suitable for scientific research scenarios with stringent requirements for measurement accuracy, experimental efficiency and anti-interference ability (such as thermal analysis of material phase transitions, thermal measurement of bio-enzyme catalytic reactions, etc.).

[0027] The micro calorimeter includes a support block 1, which is made of cast iron and is integrally formed. The bottom is equipped with an anti-slip and shock-absorbing pad, and the furnace body 2 is fixedly connected to the top by bolts. The furnace body 2 is a cylindrical stainless steel shell with an outer diameter of 300mm and a height of 400mm. The top is equipped with a detachable top cover 3, and a 5mm thick ceramic fiber heat insulation layer is pasted on the inside of the top cover 3.

[0028] The furnace body 2 is arranged from the outside to the inside as follows: heat insulation layer 5, heating cylinder 6, and heat equalization block 11. The heat insulation layer 5 is made of nano-microporous heat insulation material with a thickness of 60mm and a thermal conductivity of ≤0.02W / (m·K). The heating cylinder 6 is a cylinder made of oxygen-free copper with an inner diameter of 180mm and a height of 250mm. The outer wall is uniformly wound with nickel-chromium alloy heating wire (0.5mm in diameter, 600W total power). Four PT100 platinum resistance heating cylinder temperature sensors 7 are embedded at equal intervals along the circumference of the inner wall. The average value of the data collected by the four sensors is used as the basis for temperature control to ensure that the temperature field uniformity inside the heating cylinder is ≤±0.01℃. The top of the heating cylinder 6 is connected to the upper end cover 8 by threads, and the bottom end is welded and fixed to the lower end cover 9. Both the upper end cover 8 and the lower end cover 9 are made of polytetrafluoroethylene. An alumina ceramic heat insulation element 15 with a thickness of 20mm is attached to the top of the upper end cover 8.

[0029] The heating cylinder 6 is tightly fitted with a cylindrical heat equalizing block 11. The heat equalizing block 11 is made of oxygen-free copper with a thermal conductivity ≥401W / (m·K). A cylindrical calorimetric cavity 10 is opened at the center of the heat equalizing cavity 10. A PT1000 high-precision heat equalizing block temperature sensor 12 is embedded at the center of the calorimetric cavity 10 with a measurement accuracy of ±0.001℃. Four calorimetric channels 13 are set at equal intervals (25mm center distance between adjacent channels) around the center of the heat equalizing block 11 inside the calorimetric cavity 10. They are calorimetric channel one 131, calorimetric channel two 132, calorimetric channel 133, and calorimetric channel four 134. Each calorimetric channel 13 is a cylindrical through hole with an inner diameter of 15mm and a depth of 180mm. The top is connected to a polytetrafluoroethylene calorimetric channel top cover 4 by a thread.

[0030] Each calorimetric channel 13 is tightly fitted with a three-dimensional thermopile 14 (patent number CN114754885B) on its outer wall. The three-dimensional thermopile is composed of 8 layers of annular heat flow sensors stacked together, forming an annular heat transfer channel at the center. The calorimetric coefficient is ≥105μV / mW, and the applicable temperature range is -196℃ to 200℃, which can achieve accurate capture of heat flow in the entire temperature range.

[0031] The dynamic temperature field compensation module is integrated inside the heat distribution block 11: a ring-shaped microchannel surrounds four calorimetric channels 13, with a rectangular cross-section (3mm wide and 4mm high), and is filled with graphene composite paraffin phase change energy storage material (graphene mass fraction 5%, latent heat of phase change 185J / g, phase change temperature range -196℃~200℃); a miniature electromagnetic valve (model SYM-10, response time ≤8ms) is installed between each calorimetric channel 13 and the ring-shaped microchannel. The valve is electrically connected to the PID algorithm control module of the main control circuit through wires, which can dynamically adjust the heat exchange efficiency of the phase change material according to the temperature difference between the channels; the inner wall of the calorimetric channel 13 is coated with a gradient thermal insulation coating, with an inner layer of 12μm thick nano-zirconia thermal insulation layer (thermal conductivity 0.018W / (m·K)) and an outer layer of 6μm thick aluminum nitride thermal conductive layer (thermal conductivity 185W / (m·K)). The coating thickness at both ends along the axis is 1.5 times that of the middle area, effectively blocking heat conduction between channels.

[0032] The intelligent anti-interference detection unit includes a multi-dimensional sensor array, an interference signal analysis chip, and an interference compensation algorithm module. In the multi-dimensional sensor array, an ambient temperature sensor (model DS18B20), a humidity sensor (model SHT30), and a barometric pressure sensor (model BMP280) are fixedly installed on the outer side of the furnace body 2. A micro-vibration sensor (model ADXL345) is embedded in the inner wall of the calorimetric cavity 10. All sensors have a sampling frequency set to 100Hz to collect external environmental parameters in real time. The interference signal analysis chip uses an STM32H743ZIT6 integrated on the main control circuit board. It incorporates a machine learning model based on a BP neural network, establishing an interference-compensation mapping relationship through 500 pre-trained sets of experimental data. This allows for the quantification of environmental interference intensity and the generation of real-time compensation parameters. The interference compensation algorithm module is integrated into the host PC software (developed based on LabVIEW), receiving the compensation parameters output by the analysis chip and performing secondary corrections on the heat flow and temperature signals.

[0033] The main control circuit adopts a multi-layer PCB design and is fixedly installed in the control box on the side of the furnace body. It includes a signal acquisition module (model ADS1256, 24-bit AD conversion), a signal amplification and filtering module (using a low-noise operational amplifier AD8421, with adjustable amplification factor), a data algorithm processing chip (model FPGAEP4CE10F17C8), an interference signal analysis chip, a data transmission module (supporting both Ethernet and USB 3.0 interfaces), and a PID algorithm control module. The three-dimensional thermoelectric element 14, the uniform heating block temperature sensor 12, the heating cylinder temperature sensor 7, the heating wire, the miniature solenoid valve, and the multi-dimensional sensor array are all connected to the main control circuit through shielded wires. The main control circuit is connected to the host computer PC software via Ethernet to realize real-time data transmission and command issuance.

[0034] In this embodiment, the four calorimetric channels 13 support multi-sample high-efficiency mode and dual-channel high-precision mode, which can be switched with one click via the host computer PC software. The switching process is automatically triggered during the switching. Multi-sample high-efficiency mode: Calorimetric channels 131, 132, and 133 are used as sample channels 1, 2, and 3, respectively, while calorimetric channel 134 is used as reference channel 1. Before the experiment, standard reference samples (benzoic acid with a purity of 99.99%) are placed in all sample channels, and the heat flux reference values ​​of each channel are collected. The channel deviation coefficients k1, k2, and k3 are calculated (the measured values ​​are 0.0008 μW, 0.0007 μW, and 0.0009 μW, respectively). During the experiment, the sample channels and reference channels are connected in reverse series to obtain differential signals. Combined with the interference compensation correction value ΔI output by the intelligent anti-interference detection unit, the actual differential heat flux is calculated using the following formula: ; ; ; The measured heat flow measurement error in this mode is ±0.009μW, and the temperature measurement resolution is 0.001℃.

[0035] Dual-channel high-precision mode: Calorimetric channels 1-131 and 1-2-132 are used as sample channels 4 and 5, respectively, while calorimetric channels 3-133 and 1-4-134 are used as reference channels 2 and 3. A thermal crosstalk inverse cancellation algorithm is adopted. Based on the data collected by the ring microchannel temperature sensor, a thermal crosstalk model is established. The main control circuit outputs an inverse compensation electrical signal to the affected channels, and the actual differential heat flow is calculated using the following formula: ; ; Wherein, ΔC1 and ΔC2 are thermal crosstalk compensation values ​​(calculated from the temperature difference of the annular microchannel and the crosstalk model). The measured thermal crosstalk error between channels under this mode is ≤ ±0.0015μW, and the heat flow measurement accuracy is ±0.008μW.

[0036] Rapid mode switching calibration: When switching between the two modes, the main control circuit automatically controls the acquisition of the thermal flux response of the standard reference sample and quickly adjusts the channel deviation coefficient and compensation parameters through the algorithm. The actual calibration time is 22 seconds. After the calibration is completed, the instrument automatically enters the target working mode without manual intervention.

[0037] Experimental verification: Under the interference conditions of ambient temperature fluctuation of ±4℃, humidity change of ±15%, and micro-vibration amplitude of 3μm, the instrument of this embodiment was used to measure the phase change heat of benzoic acid samples. After 10 consecutive measurements, the phase change heat measurement value was 264.6±0.3J / g, with a relative standard deviation of 0.11%, which is 56% more stable than the existing multi-channel calorimeter (relative standard deviation of 0.25%). At the same time, three sets of samples can be tested simultaneously in a single experiment, which is 3 times more efficient than the single-channel instrument.

[0038] Example 2: Simplified example of three-channel high-efficiency mode.

[0039] The difference between this embodiment and Embodiment 1 is that the calorimetric channel 13 is set to three, which are distributed at equal distances around the center of the uniform heating block 11 (the center distance between adjacent channels is 22mm). It is only applicable to the high-efficiency mode for multiple samples and is suitable for scenarios where high throughput is the priority and accuracy is moderate (such as preliminary thermal screening experiments for a large number of samples).

[0040] In the dynamic temperature field compensation module, the annular microchannel is adapted to the three-channel layout, with a circular cross-section (4mm in diameter), and three miniature solenoid valves are used. In the intelligent anti-interference detection unit, the sampling frequency of the multi-dimensional sensor array is adjusted to 50Hz, and the interference signal analysis chip has a built-in simplified machine learning model, which reduces hardware costs while ensuring the core anti-interference effect.

[0041] During operation, one calorimetric channel was used as the reference channel, and the other two as the sample channels. Before the experiment, dynamic calibration of the channels was performed using a standard reference sample (99.99% purity naphthalene), and the channel deviation coefficients k1 and k2 were obtained (measured values ​​were 0.0012 μW and 0.0011 μW, respectively). During the experiment, the sample channel and the reference channel were connected in reverse series to obtain a differential signal. Combined with the interference compensation correction value ΔI, the signal was calculated using the formula... Calculate the actual differential heat flux.

[0042] Experimental verification: The phase transition heat measurement value of the instrument in this embodiment for naphthalene samples is 151.8±0.4J / g, with a relative standard deviation of 0.26% and a heat flow measurement error of ≤±0.02μW, which meets the accuracy requirements for preliminary screening of large batches of samples. Two sets of samples can be tested simultaneously in a single experiment, which is twice as efficient as a single-channel instrument and the manufacturing cost is reduced by 30% compared to Example 1, showing a significant cost-performance advantage.

[0043] Therefore, the present invention employs a multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation, which combines high throughput, high precision, and strong anti-interference capability, and can meet the dual requirements of scientific research for experimental efficiency and data reliability.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation, comprising a support block, a furnace body disposed above the support block, a heat insulation layer disposed sequentially inside the furnace body, a heating cylinder disposed inside the heat insulation layer, a heat homogenizing block disposed inside the heating cylinder, a calorimetric cavity disposed inside the heat homogenizing block, a temperature sensor of the heat homogenizing block disposed at the center of the calorimetric cavity, a plurality of calorimetric channels disposed at equal intervals around the center of the heat homogenizing block inside the calorimetric cavity, wherein the distance between any two adjacent calorimetric channels is the same, a three-dimensional thermopile is fitted on the outer wall of each calorimetric channel, the number of calorimetric channels is at least three, and the calorimetric channels are configured with a multi-sample high-efficiency mode or a dual-channel high-precision mode, characterized in that: It also includes a dynamic temperature field compensation module and an intelligent anti-interference detection unit; when the calorimetric channels are set to four, the multi-sample high-efficiency mode is to use three calorimetric channels as sample channel one, sample channel two and sample channel three respectively, and one as reference channel one. The dual-channel high-precision mode uses two calorimetric channels as sample channel four and sample channel five, and two as reference channels two and reference channel three, respectively. When switching between the two modes, a rapid calibration process of ≤30 seconds is automatically triggered. The multi-sample high-efficiency mode adopts a channel consistency dynamic calibration method, which obtains the deviation coefficient of each channel through a standard reference sample and calibrates it in real time. The dual-channel high-precision mode adopts a thermal crosstalk reverse cancellation algorithm, which outputs a reverse compensation electrical signal based on the temperature data of the annular microchannel. The dynamic temperature field compensation module includes an annular microchannel heat exchange structure, a phase change energy storage material, a micro electromagnetic valve, and a gradient thermal insulation coating. The annular microchannel is arranged inside the heat homogenizing block around the calorimetric channel. The phase change energy storage material is filled inside the annular microchannel. The micro electromagnetic valve is arranged between the calorimetric channel and the annular microchannel and is electrically connected to the PID algorithm control module of the main control circuit. The gradient thermal insulation coating is applied to the inner wall of the calorimetric channel. The phase change energy storage material is graphene composite paraffin, with a phase change temperature range of -196℃ to 200℃; the gradient thermal insulation coating consists of an inner nano-zirconia thermal insulation layer and an outer aluminum nitride thermal conductive layer, with the coating thickness at both ends of the axial direction being 1.5 times that of the middle region. The intelligent anti-interference detection unit includes a multi-dimensional sensor array, an interference signal analysis chip, and an interference compensation algorithm module. The multi-dimensional sensor array is respectively set outside the furnace body and inside the calorimetric cavity. The interference signal analysis chip is integrated into the main control circuit, and the interference compensation algorithm module is set in the host computer PC software. The multi-dimensional sensor array includes an ambient temperature sensor, a humidity sensor, an air pressure sensor, and a micro-vibration sensor, with a sampling frequency ≥100Hz. The interference signal analysis chip has a built-in machine learning model to quantify the interference intensity and generate compensation parameters. The heat flow signal of the sample channel is connected in reverse series with the reference channel to obtain a differential signal, and interference correction is performed by an intelligent anti-interference detection unit.

2. The multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to claim 1, characterized in that: The outer wall of the heating cylinder is evenly wound with heating wires or heating strips, and the inner wall of the heating cylinder is equipped with four heating cylinder temperature sensors, with the average value of the four temperature points used as the basis for temperature control; the top and bottom of the heating cylinder are respectively equipped with an upper end cover and a lower end cover, and a heat insulation element is provided above the upper end cover.

3. The multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to claim 1, characterized in that: The three-dimensional thermopile, the uniform heating block temperature sensor, the heating cylinder temperature sensor, the heating wire or heating belt, the miniature electromagnetic valve, and the multi-dimensional sensor array are all connected to the main control circuit. The main control circuit includes a signal acquisition module, a signal amplification and filtering module, a data algorithm processing chip, an interference signal analysis chip, a data transmission module, and a PID algorithm control module. The main control circuit is connected to the host computer PC software.

4. The multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to claim 1, characterized in that: The heat flow calculation formulas for sample channel one, sample channel two, and sample channel three are as follows: ； ； ； in, These represent the actual differential heat fluxes of sample channel one, sample channel two, and sample channel three, respectively. These are the heat flows of sample channel one, sample channel two, and sample channel three, respectively. For the heat flow of reference channel one; All are channel deviation coefficients; This is the interference compensation correction value.

5. A multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to claim 1, characterized in that: The heat flow calculation formulas for sample channel four and sample channel five are as follows: ； ； in, These are the actual differential heat flows of sample channel four and sample channel five, respectively. These represent the heat flow of sample channel four and sample channel five, respectively. , These are the heat flows of reference channel two and reference channel three, respectively. , All values ​​are thermal crosstalk compensation values.

6. A multi-channel high-precision three-dimensional micro calorimeter with dynamic temperature field compensation according to any one of claims 1-5, characterized in that, The dual-mode adaptive calibration method for this three-dimensional micro calorimeter includes the following steps: S1, Dynamic calibration of channel consistency; S2, Thermal Crosstalk Reverse Cancellation Algorithm; S3, Quick Mode Switch Calibration; Step S1 obtains the deviation coefficient through a standard reference sample and calibrates it in real time; Step S2 cancels the interference of adjacent channels through reverse compensation electrical signals; Step S3 completes the adaptive adjustment of parameters within 30 seconds.

Images