Construction method of dynamic transfer model of radionuclide discharge by fish
By constructing a dynamic transfer model of radionuclides excreted from fish, the problem of the lack of small fish excretion models in the existing technology is solved, and the dynamic transfer and impact assessment of radionuclides in fish are realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA INST FOR RADIATION PROTECTION
- Filing Date
- 2025-12-29
- Publication Date
- 2026-05-12
AI Technical Summary
Existing technologies lack dynamic models of the process by which fish expel radionuclides, especially for small fish whose tissue sites cannot be distinguished, making methods for estimating concentration coefficients inapplicable.
A dynamic transfer model of radionuclides excreted by fish was constructed. By establishing a two-compartment model of water and fish and introducing correction parameters, the dynamic transfer of radionuclides in the water and fish body was described. Differential equations and parametric equations were used to simulate the excretion process of radionuclides, and specific parameters were solved for zebrafish.
This study provides a method for researching the dynamic transfer of radionuclides excreted from small fish, which can accurately simulate the concentration and excretion of radionuclides in fish, providing a basis for assessing the impact of radionuclides on the aquatic environment.
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Figure CN122019929A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of environmental impact assessment technology for nuclear facilities, and in particular to a method for constructing a dynamic transfer model of radionuclide excretion by fish. Background Technology
[0002] Nuclear energy, characterized by its economy and efficiency, is an ideal clean energy source that has fueled rapid economic development. However, while creating economic value, nuclear power also results in the discharge of liquid effluents containing radioactive nuclides into nearby waters, potentially impacting the aquatic environment and organisms. Studies have shown that fish, as a key link in the aquatic food chain, can accumulate radioactive nuclides through direct contact with water or ingestion, posing a potential threat to human health through biomagnification. Simultaneously, when fish contaminated with radioactive nuclides enter clean waters, the radioactive nuclides within their bodies will enter the water, polluting the aquatic environment due to their ability to metabolize them. Therefore, to understand the metabolic capacity of fish for radioactive nuclides and to subsequently assess the impact of radioactive nuclide effluent discharges on the aquatic environment, it is necessary to study the dynamic transfer patterns of radioactive nuclides during discharge.
[0003] In existing technologies, there are only methods for estimating the concentration coefficient of radionuclides in water equilibrium for fish, but no methods exist for establishing dynamic models of the radionuclide excretion process in fish. Furthermore, the methods for estimating the concentration coefficient are not applicable to small fish that cannot distinguish between different tissue sites or the rapid and slow phases of radionuclide excretion. Summary of the Invention
[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a method for constructing a dynamic transfer model of radionuclide excretion by fish. This method can simulate the dynamic transfer process of radionuclide excretion by fish, thereby further assessing the impact of contaminated fish on the aquatic environment.
[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A method for constructing a dynamic transfer model of radionuclide excretion in fish, characterized by comprising the following steps: A two-compartment model of water body and fish was established, and differential equations describing the dynamic transfer of radionuclides in water body and fish body during the excretion of radionuclides were obtained; Assuming that some radionuclides accumulate in the muscle tissue of fish and are no longer excreted, a correction parameter is introduced. , The specific activity of radionuclides that cannot be excreted from the fish body is represented by the differential equation. After transformation, the parametric equation of the specific activity of radionuclides in the fish body as a function of time is obtained. For the aforementioned parametric equation, let the initial specific activity of the radionuclide during the effluent process be . Biological half-out period is The system of equations was obtained and solved simultaneously to obtain a dynamic transfer model of radionuclides in the fish body during the excretion process.
[0006] The initial specific activity of radionuclides The specific activity of the unexcreted portion And biological half-excretion period is The specific values are substituted into the dynamic transfer model of radionuclides in the fish body during the excretion process to obtain the corresponding relationship of the dynamic transfer model of radionuclides excreted by fish.
[0007] Furthermore, the dynamic transfer model of the radionuclide within the fish during the excretion process is as follows: (1) In the formula, C 1( t ( ) represents the time of radioactive nuclides in the fish body t Specific activity, Bq / kg.
[0008] Furthermore, the differential equation is: (2) In the formula, The radioactive decay constant is 1 / d; k 10 is the migration rate constant of the radionuclide from the fish body to the water body, 1 / d; Specific activity of nuclides that cannot be excreted from the fish, in Bq / kg.
[0009] Furthermore, the parametric equation is as follows: (3) In the formula, K Let be any non-zero constant.
[0010] Furthermore, the system of equations is as follows: .
[0011] Furthermore, the fish in question is a zebrafish.
[0012] Furthermore, the zebrafish used is a wild-type AB strain zebrafish.
[0013] Furthermore, the radioactive nuclide is 137 Cs.
[0014] Furthermore, the concentration process of the radionuclide takes at least 198 days.
[0015] Furthermore, because radioactive nuclides are 137 Cs has a long half-life, and the radioactive decay constant in the equations is... Negligible.
[0016] Compared with existing technologies, the beneficial effects of this invention are as follows: This method constructs a dynamic transfer model of radionuclide excretion in fish, focusing on the concentration and excretion of radionuclides within the fish body, and no longer relying on the acquisition of transfer parameters. This invention provides a new method for studying the dynamic transfer process of radionuclide excretion in small fish, where it is difficult to distinguish different tissue sites and fast and slow phases within the body. It lays the foundation for further understanding the metabolic capacity of fish for radionuclides, mastering the dynamic transfer patterns of their radionuclide excretion, and subsequently assessing the impact of liquid radionuclide effluent discharge on the aquatic environment. Attached Figure Description
[0017] Figure 1 This is a block diagram of a reservoir model established for the dynamic transfer process of radionuclides between water and fish in an embodiment of the present invention.
[0018] Figure 2 The zebrafish excretion process obtained in this embodiment of the invention 137 A comparison chart of measured and calculated Cs specific activity values. Detailed Implementation
[0019] To enhance understanding of the present invention, we will now describe it in further detail with reference to the accompanying drawings. These embodiments are for illustrative purposes only and do not constitute a limitation on the scope of protection of the present invention.
[0020] A specific embodiment of a method for constructing a dynamic transfer model of radionuclide excretion in fish, wherein wild-type AB strain zebrafish is used as the research object, and the method includes the following specific steps: S1: Establish as follows Figure 1 The water-zebrafish two-compartment model is shown, and a systems analysis method is used for analysis. It is assumed that some radionuclides accumulate in the muscle of the fish and are no longer excreted, and correction parameters are introduced. The description obtained is of the radioactive nuclides during the discharge process. 137 The differential equation for the dynamic transfer of Cs in water and zebrafish is as follows: (2) In the formula, The radioactive decay constant is 1 / d; k 10 is the migration rate constant of the radionuclide from the fish body to the water body, 1 / d; Specific activity of nuclides that cannot be excreted from the fish, in Bq / kg;C 1( t ( ) represents the time of radioactive nuclides in the fish body t Specific activity, Bq / kg.
[0021] S2.1: Order ， Equation (2) can be simplified to: (4) S2.2: After several transformations of equation (4), we get the following: (6) (7) According to the relevant theory of integrals, we can obtain from equation (7): (8) In the formula, C It is an arbitrary constant.
[0022] Equation (8) can be further transformed to obtain: (9) (10) Simplifying equation (10) yields: (5) In the formula, K Let be any non-zero constant.
[0023] S2.3: Order ， Substituting this back into equation (5), we obtain the radionuclides found in zebrafish. 137 The parametric equation for the change of Cs specific activity over time is shown below: (3) S3: For the parametric equation (3) obtained in S2, let the initial specific activity of the radionuclide during the discharge process be... Biological half-out period is Given the initial conditions, we can obtain the following system of equations: Solving the above system of equations yields the results of the radioactive nuclides emitted during the process. 137 The dynamic transfer model of Cs in zebrafish is as follows: (1) S4: Initial specific activity of the radionuclide The specific activity of the unexcreted portion And biological half-excretion period is Substituting the specific values into equation (1) yields the corresponding radionuclides emitted during the process. 137 A dynamic transfer model of Cs in zebrafish.
[0024] The excretion mechanism of radionuclides in fish is a key aspect of assessing long-term ecological risks. To study the dynamic transfer patterns of radionuclides in aquatic ecosystems and assess the impact of liquid radionuclide effluents on fish in the aquatic environment, a model analysis method can be used to establish a dynamic transfer model of radionuclides excreted by fish.
[0025] The model is constructed by treating the migration of radionuclides between water and fish as a combination of a water reservoir and a fish reservoir with certain boundary spaces. Radionuclides can migrate and mix freely between the reservoirs, and the transfer rate of radionuclides is characterized by a specific rate constant or transfer coefficient, so as to analyze the entire system.
[0026] To verify the effectiveness of the model, the following comparative experiments were conducted.
[0027] zebrafish 137 Taking the construction of the excretion dynamic transfer model of Cs as an example, the experiment used wild-type AB strain zebrafish as the research object. Before the excretion experiment began, the zebrafish were transferred to a container of clean water to wash away any residue remaining on their bodies. 137 The Cs nuclide was then transferred to an uncontaminated discharge tank.
[0028] During the expulsion experiment, the water in the expulsion tank was regularly changed daily, while an equal amount of fresh water was added to maintain a constant concentration of radionuclide activity in the water. The entire expulsion process lasted 198 days, with samples taken on days 1, 3, 6, 10, 17, 22, 33, 60, 109, 128, and 198 for live measurements. The radionuclide activity concentration in zebrafish at each sampling time was obtained. 137 Measured values of Cs activity concentration, experimental results are as follows: Figure 2 The measured values are shown in the figure.
[0029] Then, the initial specific activity of the radionuclide was... The specific activity of the unexcreted portion And biological half-excretion period is Substitute the specific parameter values into equation (1), where =2370 Bq / kg, =5810 Bq / kg, =70d, and finally the corresponding radionuclides were obtained during the discharge process. 137Dynamic transfer model of Cs in zebrafish: The zebrafish obtained during the excretion process in the above embodiments 137 The calculated values of Cs specific activity from the model were compared with the measured values, such as... Figure 2 As shown.
[0030] from Figure 2 It can be seen that when excretion occurs more than 30 days later, the zebrafish obtained using this method... 137 The calculated Cs specific activity values from the model closely approximate the measured values. The calculated and experimental values from the dynamic transfer model established using this method show relatively good agreement, demonstrating the effectiveness of the method. Therefore, this method is highly practical and provides a new approach for studying the dynamic transfer process of radionuclides excreted from small fish, where it is difficult to distinguish between different tissue sites and between fast and slow phases.
[0031] The above specific embodiments are only for illustrating the technical concept and structural features of the present invention, and are intended to enable those skilled in the art to implement them. However, the above content does not limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit and essence of the present invention should fall within the scope of protection of the present invention.
Claims
1. A method for constructing a dynamic transfer model of radionuclide excretion in fish, characterized in that, Includes the following steps: A two-compartment model of water body and fish was established, and differential equations describing the dynamic transfer of radionuclides in water body and fish body during the excretion of radionuclides were obtained; Assuming that some radionuclides accumulate in the muscle tissue of fish and are no longer excreted, a correction parameter is introduced. , The specific activity of radionuclides that cannot be excreted from the fish body is represented by the differential equation. After transformation, the parametric equation of the specific activity of radionuclides in the fish body as a function of time is obtained. For the aforementioned parametric equation, let the initial specific activity of the radionuclide during the effluent process be . Biological half-out period is The system of equations was obtained and solved simultaneously to obtain a dynamic transfer model of radionuclides in the fish during the excretion process. The initial specific activity of radionuclides The specific activity of the unexcreted portion And biological half-excretion period is The specific values are substituted into the dynamic transfer model of radionuclides in the fish body during the excretion process to obtain the corresponding relationship of the dynamic transfer model of radionuclides excreted by fish.
2. The method for constructing a dynamic transfer model of radionuclide excretion in fish according to claim 1, characterized in that: The dynamic transfer model of radionuclides within the fish body during the excretion process is as follows: （1） In the formula, C 1( t ( ) represents the time of radioactive nuclides in the fish body t Specific activity, Bq / kg.
3. The method for constructing a dynamic transfer model of radionuclide excretion in fish according to claim 2, characterized in that: The differential equation is: （2） In the formula, The radioactive decay constant is 1 / d; k 10 is the migration rate constant of the radionuclide from the fish body to the water body, 1 / d; Specific activity of nuclides that cannot be excreted from the fish, in Bq / kg.
4. The method for constructing a dynamic transfer model of radionuclide excretion in fish according to claim 3, characterized in that: The parametric equation is as follows: （3） In the formula, K Let be any non-zero constant.
5. The method for constructing a dynamic transfer model of radionuclide excretion in fish according to claim 4, characterized in that: The system of equations is 。 6. The method for constructing a dynamic transfer model of radionuclide excretion in fish according to claim 1, characterized in that: The fish in question is a zebrafish.
7. The method for constructing a dynamic transfer model of radionuclide concentration in fish according to claim 6, characterized in that: The zebrafish used are wild-type AB strain zebrafish.
8. The method for constructing a dynamic transfer model of radionuclide excretion in fish according to claim 1, characterized in that: The radioactive nuclide is 137 Cs.
9. The method for constructing a dynamic transfer model of radionuclide concentration in fish according to claim 8, characterized in that: The concentration process of the radionuclide takes at least 198 days.
10. The method for constructing a dynamic transfer model of radionuclide concentration in fish according to claim 8, characterized in that: Because radioactive nuclides are 137 Cs has a long half-life, and the radioactive decay constant in the equations is... Negligible.