Radiation source preparation apparatus

Abstract

The application relates to a radioactive source preparation device. The radioactive source preparation device is used to realize a radioactive source preparation method, which comprises the following steps: obtaining a target nuclide irradiation body according to the application requirement of well logging, and irradiating the target nuclide irradiation body placed in a radiation cavity of the radioactive source preparation device with light neutrons until the target nuclide irradiation body meets a preset condition, so that a prepared radioactive source is obtained. The radioactive source prepared by the method can meet the well logging requirement, and the life of the rays of the prepared radioactive source is fixed and relatively short. After the application of the radioactive source is completed, the radioactivity of the radioactive source disappears in a very short time and reduces to a safe range, so that the risk caused by the out-of-control radioactive source is greatly reduced, radioactive accidents can be avoided to a certain extent, and the occurrence rate of radioactive accidents is reduced.

Description

Technical Field

[0001] This application relates to the field of radioactive well logging technology, and in particular to a radioactive source preparation device. Background Technology

[0002] Well logging is an important branch of geophysics, widely used in the exploration and development of important resources such as oil and gas fields, metal deposits, and coal. While there are various well logging techniques, radioactive logging technology has received considerable attention due to limitations imposed by downhole conditions (such as dry wells, oil-based mud, and high-salinity mud).

[0003] In radioactive logging, the main process involves loading a radioactive source into a downhole instrument and extending it underground. The exploration is achieved by utilizing the interaction between the radiation generated by the radioactive source and the formation material.

[0004] However, the radioactive sources used in radioactive logging have low safety, leading to a high incidence of radioactive accidents. Summary of the Invention

[0005] Therefore, it is necessary to provide a radioactive source preparation device to address the above-mentioned technical problems. This device is used to implement a radioactive source preparation method that can produce a safe radioactive source that meets the requirements of well logging and reduce the incidence of radioactive accidents.

[0006] In a first aspect, embodiments of this application provide a method for preparing a radioactive source, the method comprising:

[0007] Based on the application requirements of well logging, obtain the target nuclide irradiant; the target nuclide irradiant includes at least one working nuclide.

[0008] The target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment is irradiated with photoneutrons until the target nuclide irradiator meets the preset conditions, thus obtaining the prepared radioactive source.

[0009] In one embodiment, if the radioactive source is a gamma radioactive source, the preset conditions include gamma radiation conditions; by irradiating the target nuclide irradiator placed in the radiation cavity of the radioactive source preparation device with photoneutrons until the target nuclide irradiator meets the preset conditions, the prepared radioactive source is obtained, including:

[0010] Photoneutrons are generated by a neutron converter and used to irradiate the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the gamma emission conditions, thus obtaining a gamma radiation source.

[0011] In one embodiment, the gamma radiation conditions include the target ray intensity value; photoneutrons are generated by a neutron converter to irradiate the target nuclide irradiator within the radiation cavity until the target nuclide irradiator meets preset conditions, thus obtaining the prepared radioactive source, including:

[0012] A gamma radiation source is prepared by reacting the atomic nuclei within the target nuclide irradiation body with the rays of photoneutrons until the ray intensity of the target nuclide irradiation body equals the ray intensity of the target ray.

[0013] In one embodiment, the neutron converter is obtained by targeting a working nuclide with a reaction threshold energy lower than a preset threshold energy threshold.

[0014] In one embodiment, the method further includes:

[0015] Electrons generated by an electron accelerator in a radioactive source preparation device are accelerated to obtain electrons with the target electron energy value.

[0016] Electrons are converted into radiation by an electron conversion target in a radioactive source preparation device;

[0017] Radiation is converted into photoneutrons using a neutron converter.

[0018] In one embodiment, if the radioactive source is a mixed radioactive source, the preset conditions include mixed radioactive conditions; by irradiating the target nuclide irradiator placed in the radiation cavity of the radioactive source preparation device with photoneutrons until the target nuclide irradiator meets the preset conditions, the prepared radioactive source is obtained, including:

[0019] Photoneutrons are generated by a neutron converter and used to irradiate the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the gamma emission conditions, thus obtaining a gamma radiation source.

[0020] By combining a gamma radiation source with a neutron converter, a hybrid radiation source is prepared; the radiation intensity value of the gamma radiation source meets the preset radiation intensity conditions.

[0021] In one embodiment, if the radioactive source is a neutron radioactive source, then after the preparation of the mixed radioactive source is completed, the method further includes:

[0022] The gamma rays emitted by the gamma radiation source are shielded to obtain a neutron radiation source from the mixed radiation source.

[0023] In one embodiment, if the radioactive source is a hybrid radioactive source or a neutron radioactive source, the gamma radioactive source used to generate the hybrid radioactive source has a radiation energy value greater than the reaction threshold energy for the nuclear reaction to be generated by the neutron converter.

[0024] In one embodiment, the application requirements for logging include logging duration and the intensity of the radioactive source required for logging;

[0025] Based on the application requirements of well logging, obtain the target radionuclide irradiation body, including:

[0026] Select at least one working nuclide from a pre-defined irradiant material library that meets the requirements of logging duration and the radiation energy value of the required radioactive source for logging, and obtain the target nuclide irradiant.

[0027] In a second aspect, embodiments of this application provide a radioactive source preparation apparatus, which includes: a processor, an electron accelerator, an electron conversion target, and an irradiation cavity. The processor is used to implement the steps of the method in any of the embodiments of the first aspect above through the electron accelerator, the electron conversion target, and the irradiation cavity.

[0028] Thirdly, embodiments of this application also provide a computer device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method in any of the embodiments of the first aspect described above.

[0029] Fourthly, embodiments of this application also provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the method in any of the embodiments of the first aspect described above.

[0030] Fifthly, embodiments of this application also provide a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the method in any of the embodiments of the first aspect described above.

[0031] This application provides a radioactive source preparation device for implementing a radioactive source preparation method. The method includes: obtaining a target nuclide irradiant, i.e., at least one working nuclide, according to the application requirements of well logging; and irradiating the target nuclide irradiant placed in the radiation cavity of the radioactive source preparation device with photoneutrons until the target nuclide irradiant meets preset conditions to obtain a prepared radioactive source. The radioactive source prepared using this method not only meets the well logging requirements but also ensures that the lifetime of the prepared radioactive source's radiation is fixed and relatively short. After the application of the radioactive source ends, the radioactivity of the source will disappear within a very short time, dropping to a safe range, greatly reducing the risk of uncontrolled radioactive source activity and thus, to a certain extent, avoiding radioactive accidents and reducing their incidence. Simultaneously, the method can prepare a short-lived radioactive source, reducing resource waste during application and thus lowering economic costs. Furthermore, the method can prepare radioactive sources that meet application requirements, enabling the preparation of radioactive sources for different radioactive scenarios, making the radioactive source preparation method more versatile and expanding its application scenarios. Attached Figure Description

[0032] Figure 1 This is a diagram illustrating the application environment of a radioactive source preparation method in one embodiment;

[0033] Figure 2 This is a schematic flowchart of a radioactive source preparation method in one embodiment;

[0034] Figure 3 This is a graph showing the relationship between photoneutron energy and neutron fluence rate in another embodiment;

[0035] Figure 4 This is a graph showing the relationship between the radiation energy and half-life of a gamma radiation source in another embodiment.

[0036] Figure 5 for Figure 4 Enlarged view of the corresponding part of the embodiment;

[0037] Figure 6 This is a flowchart illustrating the radioactive source preparation method in another embodiment;

[0038] Figure 7 This is a schematic diagram showing the positional relationship of indium inserted into beryllium in another embodiment;

[0039] Figure 8 This is a schematic diagram illustrating the process of generating a gamma radiation source and lowering it into a well, as described in another embodiment.

[0040] Figure 9This is a schematic diagram illustrating the process of generating a hybrid radioactive source and lowering a gamma radioactive source into a well, as described in another embodiment.

[0041] Figure 10 This is a structural block diagram of a radioactive source preparation apparatus in one embodiment;

[0042] Figure 11 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0044] In the field of well logging, radioactive logging is a primary method for measuring indicators such as lithological density and key elemental composition. It is widely used due to its broad applicability and minimal dependence on downhole conditions (such as dry wells, oil-based mud, and high-salinity mud). Radioactive logging involves placing a radioactive source in the wellbore and extending it deep underground. The interaction between the radiation generated by the source and the formation material allows for exploration, measuring indicators such as lithological density, hydrogen content, oil saturation, and porosity. The logging results are then obtained based on these measurements.

[0045] Radioactive sources in related technologies continuously and over long periods release radiation according to a predetermined attenuation pattern, which cannot be artificially controlled, leading to a high incidence of radioactive accidents. Therefore, this application provides a method for preparing a radioactive source that can produce a safe radioactive source that meets the requirements of well logging, thereby reducing the incidence of radioactive accidents.

[0046] The above-mentioned method for preparing radioactive sources can be applied to Figure 1 In the illustrated application environment, the environment includes a processor, an electron accelerator, an electron conversion target, and an irradiation cavity. The processor executes the radioactive source preparation method via the electron accelerator, electron conversion target, and irradiation cavity. The processor may include, but is not limited to, microcontrollers, central processing units, digital signal processors, programmable logic devices, etc., and this application embodiment does not limit this. Optionally, the processor is communicatively connected to the electron accelerator and electron conversion target, respectively. This communication method can be Wi-Fi, mobile network, or Bluetooth connection, etc. The radioactive source prepared in this application embodiment can be applied to technologies such as online elemental analysis and security inspection. However, this application embodiment uses the application of the prepared radioactive source in well logging technology as an example to illustrate the implementation process of the radioactive source preparation method. The following embodiments will use the processor as the execution subject to illustrate the implementation process of the radioactive source preparation method.

[0047] like Figure 2The diagram shown is a schematic flowchart of a radioactive source preparation method provided in an embodiment of this application. This radioactive source preparation method may include the following steps:

[0048] S100. Based on the application requirements of well logging, obtain the target nuclide irradiant; the target nuclide irradiant includes at least one working nuclide.

[0049] Specifically, the processor in the radioactive source preparation equipment can determine at least one working nuclide based on the application requirements of well logging. Optionally, the application requirements of well logging can be attribute information of the radioactive source required for well logging prepared by using the working nuclide, which may include information such as activity and / or logging duration.

[0050] It should be noted that different radioactive sources may correspond to the same or different target nuclide irradiators; the working nuclide in the target nuclide irradiator can be understood as the material required to prepare the radioactive source.

[0051] S200. The target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment is irradiated with photoneutrons until the target nuclide irradiator meets the preset conditions, and the prepared radioactive source is obtained.

[0052] Based on the target nuclide irradiator determined in the above steps, the processor in the radioactive source preparation equipment can control the mechanical device to place the target nuclide irradiator into the radiation cavity of the radioactive source preparation equipment. Further, the processor controls the photoneutron irradiation of the target nuclide irradiator within the radiation cavity until the target nuclide irradiator meets preset conditions, thus obtaining the prepared radioactive source.

[0053] In one embodiment, the method of obtaining a prepared radioactive source by controlling the photoneutron irradiation of the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the preset conditions can be as follows: the photoneutron irradiation of the target nuclide irradiator in the radiation cavity is controlled according to the target irradiation duration, and when the photoneutron irradiation duration is equal to the target irradiation duration, it is determined that the target nuclide irradiator meets the preset conditions, and the prepared radioactive source is obtained.

[0054] In another embodiment, the aforementioned photoneutron irradiation can be understood as a reaction process. In some scenarios, although the selected target nuclide irradiator meets the application requirements of well logging, the duration of photoneutron irradiation varies, resulting in radioactive sources that may be the same or different. Therefore, to prepare a radioactive source that meets the application requirements of well logging, the method of controlling the photoneutron irradiation of the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the preset conditions can also be to obtain the parameter change curves of the radioactive source at different times during the photoneutron irradiation process, and determine whether the target nuclide irradiator meets the preset conditions based on the parameter change curves of the radioactive source at different times. If the target nuclide irradiator meets the preset conditions, the photoneutron irradiation is stopped, and the prepared radioactive source is obtained.

[0055] Optionally, the aforementioned preset conditions may include the radiation energy value of the radioactive source reaching a specific energy threshold, the half-life of the radiation from the radioactive source reaching a specific time threshold, and the intensity of the radiation from the radioactive source reaching a specific intensity threshold. The half-life of the radiation from the radioactive source can be understood as the time generally required for the radioactivity of the radioactive source to decrease.

[0056] Furthermore, radioactive logging can be achieved using a prepared radioactive source. Since the half-life of the radiation produced by the prepared radioactive source is fixed, the radioactivity of the source will drop to a safe range in a very short time after the radioactive logging is completed. This greatly reduces the risk of uncontrolled radioactive sources and can, to some extent, prevent radioactive accidents and reduce their incidence.

[0057] In this process, after radioactive logging is completed, the intensity of the radioactive source will be significantly lower than before it was lowered into the well. Meanwhile, during the lowering process, because the newly prepared radioactive source is highly radioactive, to prevent harm to the human body from the radioactivity, the processor can control a mechanical device to install the radioactive source into the lowering instrument and lower it into the well.

[0058] In this embodiment, the prepared radioactive source decays according to its corresponding half-life under natural conditions and is not affected by factors such as well pressure, temperature, or collisions. During the working period, the activity of the radioactive source meets the requirements for well logging applications. If a fall-in-well accident occurs during the well-running process, the radioactivity of the source can be guaranteed to decrease to a safe range within a short time based on the working parameters used during preparation. This reduces the complexity of retrieval (or eliminates the need for retrieval) and avoids potential resource and property losses due to well sealing or other control measures.

[0059] The radioactive source preparation method provided in this application embodiment can obtain a target nuclide irradiator, i.e., at least one working nuclide, according to the application requirements of well logging, and irradiate the target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment with photoneutrons until the target nuclide irradiator meets the preset conditions, thereby obtaining the prepared radioactive source. The radioactive source prepared using the above method not only meets the needs of well logging but also ensures a fixed and short lifetime of radiation. After application, the radioactivity of the source dissipates quickly, dropping to a safe level, significantly reducing the risk of uncontrolled radioactive source spread and thus mitigating the risk of radioactive accidents. Furthermore, the short-lived nature of the source reduces resource waste and lowers economic costs. Moreover, the method allows for the preparation of radioactive sources that meet various application requirements, enabling the preparation of sources for different radioactive scenarios, thus enhancing the versatility and expanding the application scenarios. Additionally, the raw materials used in this method, namely the working nuclide, can be reused, allowing the preparation of multiple different radioactive sources from the same raw material, further reducing the economic cost of preparing multiple different sources.

[0060] In some scenarios, different types of radioactive sources need to be prepared according to the required radiation intensity values ​​of the radioactive source for the application. The following describes the process of preparing a radioactive source by taking a gamma radioactive source as an example, and irradiating the target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment with photoneutrons until the target nuclide irradiator meets the preset conditions.

[0061] In one embodiment, if the radiation source is a gamma radiation source, the preset conditions include a first gamma radiation condition; the steps in S200 above may include: generating photoneutrons through a neutron converter to irradiate the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the first gamma radiation condition, thereby obtaining a gamma radiation source.

[0062] Specifically, the neutron converter can be obtained through a target working nuclide, which may or may not be the same as any working nuclide in the target nuclide irradiator.

[0063] In practical applications, regardless of the energy value of the photoneutron, as long as photoneutrons are generated, they can irradiate the target nuclide to produce a gamma radiation source.

[0064] The processor can generate photoneutrons through a neutron converter to irradiate the target nuclide irradiator within the radiation cavity until the target nuclide irradiator meets the first gamma emission condition, thus obtaining a gamma radiation source. Optionally, gamma radiation sources will be generated regardless of the irradiation duration during the irradiation process. However, gamma radiation sources generated by different irradiation durations may not necessarily meet the requirements for well logging applications. Therefore, during the irradiation process, irradiation will only stop when the target nuclide irradiator meets the first gamma emission condition, and at this point, the gamma radiation source required for well logging will be generated. Otherwise, if the target nuclide irradiator does not meet the first gamma emission condition, the generated gamma radiation source will not meet the requirements for well logging applications.

[0065] Optionally, the first gamma radiation condition may be that the irradiation time of the target nuclide reaches a specific irradiation time threshold and / or the activity of the target nuclide reaches a specific activity threshold, etc.

[0066] In one embodiment, the first gamma radiation condition includes the target ray intensity value; the step of generating photoneutrons through a neutron converter to irradiate the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the preset conditions to obtain the prepared radioactive source may include: the photoneutron rays react with the atomic nuclei in the target nuclide irradiator until the ray intensity value of the target nuclide irradiator is equal to the target ray intensity value, then stopping the nuclear reaction to obtain the prepared gamma radioactive source.

[0067] The neutron converter is obtained by using a working nuclide with a reaction threshold energy lower than a preset threshold energy threshold.

[0068] In this embodiment, only photoneutrons generated by a neutron converter obtained from a working nuclide with a reaction threshold energy lower than a preset threshold energy can excite the nuclei in the target nuclide irradiator to undergo a nuclear reaction, which can be an (n, γ) reaction. It should be noted that the neutron converter can be obtained by processing the shape of the working nuclide with a reaction threshold energy lower than the preset threshold energy and then placing the processed working nuclide into a suitable container. Optionally, the above processing can be understood as opening a hole at any position of the working nuclide; that is, no actual nuclear reaction treatment of the working nuclide is required to obtain the neutron converter.

[0069] In practical applications, the radiation intensity value A of a mixed radioactive source can be expressed by the following formula:

[0070] (1);

[0071] In the above formula (1), A represents the intensity value (1 / s) of a specific gamma ray produced by the gamma radiation source, and N represents the number of target nuclide atoms in the target nuclide irradiator. This represents the (n, γ) reaction cross section (barn, 10) of the target nuclide irradiation body to a neutron with incident energy E. -24 cm 2 ), The neutron flux rate in the irradiation cavity with energies from E to E+dE represents the neutron flux rate. cm -2 s -1 ), This represents the decay constant (1 / s) of the active nuclei generated by photoneutron irradiation. Indicates irradiation duration (s). This represents the time (in seconds) from the end of photoneutron irradiation to the start of logging. The percentage represents the intensity (%) of gamma rays with specific characteristics produced by activated nuclei, wherein the above... This can be understood as the intensity value of a neutron.

[0072] For example, if the electron accelerator in the radioactive source preparation equipment is 9 MeV (MeV is a unit of energy) and the target power of the electron accelerator is 900 W, then the irradiation cavity in the radioactive source preparation equipment can generate 2.4 × 10⁻⁶ W. 9 cm -2 s -1 The total neutron flux rate, such as Figure 3 The graph shows the relationship between photoneutron energy and neutron fluence rate during photoneutron generation. The horizontal axis represents photoneutron energy, and the vertical axis represents neutron fluence rate. The aforementioned electron accelerator can be a component of an electron accelerator neutron source.

[0073] Among them, the duration of radiation over time When the gamma radiation source is equal to infinity, the radiation intensity value A is equal to... At this point, the radiation intensity value A of the gamma-ray source can represent the neutron fluence rate provided. The upper limit of the intensity of gamma rays from a gamma-ray source prepared by neutron energy.

[0074] In practical applications, neutron converters are used as... 9 Taking Be (threshold energy 1.67 MeV) as an example, if the half-life of the gamma radiation source to be prepared is between half an hour and two days, the corresponding change curves of gamma radiation sources with different ray energies, different half-lives, and corresponding ray intensity values ​​generated during irradiation are shown in the figure below. Figure 4 As shown. Figure 4 The horizontal axis represents the half-life of the gamma-ray source, and the vertical axis represents the energy value of the gamma-ray source. Figure 4 The different dots represent gamma-ray sources with different energies, half-lives, and corresponding intensity values. Each dot has a different color, and the specific intensity value can be determined by... Figure 4 The color stops on the right are determined, among which, Figure 4 The color code on the right can be understood as the color code corresponding to the radiation intensity value of the gamma radiation source. In the embodiment of this application, the radiation intensity value of the gamma radiation source is represented by log10 (Nspb).

[0075] like Figure 5 for Figure 4 Enlarged image, from Figure 5 Therefore, In, Na, Mn, and Ga are the working nuclides with higher log10 (Nspb) values. Figure 4 and Figure 5 The points within the shaded area represent the optimal working nuclides for preparing radioactive sources within a predetermined half-life range. Figure 4 and Figure 5 This is a scatter plot showing the corresponding changes in radiation energy, half-life, and intensity values ​​between different gamma radiation sources, using a preset half-life range of half an hour to two days as an example. Figure 4 and Figure 5 The points on the same horizontal line correspond to gamma rays from the same gamma source with the same half-life but different energies and intensities.

[0076] The technical solution in this application embodiment can generate photoneutrons through a neutron converter to irradiate the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the first gamma emission condition, thus obtaining a gamma radiation source. The gamma radiation source prepared by this method can not only meet the logging requirements, but also ensure that the lifetime of the prepared gamma radiation source is fixed and relatively short. After the application of the gamma radiation source is completed, the radioactivity of the gamma radiation source will drop to a safe range in a very short time, greatly reducing the risk of uncontrolled radiation source, thereby avoiding radioactive accidents to a certain extent and reducing the incidence of radioactive accidents. At the same time, this method can prepare a gamma radiation source with low radioactivity that can meet the logging requirements, thereby reducing radiation to the human body during the logging process and improving personal safety.

[0077] The process of obtaining photoneutrons required for photoneutron irradiation is described below. In one embodiment, before performing the steps in S200 above, as follows: Figure 6 As shown, the above-mentioned method for preparing a radioactive source may further include the following steps:

[0078] S300: The electrons generated by the electron accelerator are accelerated by the electron accelerator of the radioactive source preparation equipment to obtain electrons with the target electron energy value.

[0079] Specifically, the processor in the radioactive source preparation equipment can control the operation of the electron accelerator in the radioactive source preparation equipment. After the electron accelerator is working, it can accelerate the electrons generated by its cathode. When the energy value of the electron is equal to the target electron energy value, the electron accelerator is controlled to be turned off, and at this time, electrons with the target electron energy value are obtained.

[0080] Optionally, the target electron energy value can be determined based on the radiation energy value required for logging the radioactive source to be prepared. Optionally, the operating speed of the electron accelerator can be controlled, and the specific operating speed is not limited in this embodiment. It should be noted that different radioactive sources require the generation of electrons with different energy values. In practical applications, the generation of electrons with different energy values ​​can be controlled by controlling the acceleration duration and acceleration speed. Optionally, the electron accelerator can be an accelerator radiation source or a hadron accelerator; this is not limited in this embodiment.

[0081] S400: Electrons are converted by the electron conversion target of the radioactive source preparation equipment to obtain radiation.

[0082] Specifically, the processor can convert electrons into radiation through the electron conversion target of the radiation source preparation device. Optionally, the radiation can be alpha rays or beta rays, etc., but in the embodiments of the application, the radiation is X-rays. Optionally, the conversion of electrons into radiation is an instantaneous process, so in practical applications, there is no need to control the conversion time.

[0083] S500 converts radiation into photoneutrons through a neutron converter.

[0084] Based on the radiation obtained in the above steps, the processor can convert the radiation into photoneutrons using a neutron converter. Optionally, the conversion of radiation into photoneutrons is an instantaneous process, so in practical applications, there is no need to control the conversion time.

[0085] It should be noted that as long as the energy value of the electron obtained above is equal to the energy value of the target electron, the resulting photoneutrons will be able to meet the requirements for photoneutron irradiation.

[0086] The technical solution in this application embodiment can accelerate electrons generated by an electron accelerator in a radioactive source preparation device to obtain electrons with the target electron energy value. The electrons are then converted into radiation by an electron conversion target in the radioactive source preparation device. Finally, the radiation is converted into photoneutrons by a neutron converter. This method can obtain the photoneutrons required during the photoneutron irradiation process when preparing different radioactive sources. The method for obtaining photoneutrons is relatively simple and does not require human intervention, which can reduce radiation to the human body and improve personal safety.

[0087] In some scenarios, different types of radioactive sources need to be prepared according to the required radiation intensity values ​​of the radioactive source for the application. The following describes the process of preparing a radioactive source by taking a mixed radioactive source as an example, and irradiating the target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment with photoneutrons until the target nuclide irradiator meets the preset conditions.

[0088] In one embodiment, if the radiation source is a hybrid radiation source, the preset conditions include a second gamma radiation condition; the steps in S200 above may include: generating photoneutrons through a neutron converter to irradiate the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the second gamma radiation condition to obtain a gamma radiation source, and combining the gamma radiation source with the neutron converter to obtain the prepared hybrid radiation source; the radiation intensity value of the gamma radiation source meets the preset radiation intensity condition.

[0089] It should be noted that the neutron converter in this step can be the same as or different from the neutron converter in the previous steps. To achieve the goal of generating a neutron radiation source from the neutron converter in this step, any neutron converter that meets the specific content requirements of the target working nuclide can be used. In the embodiments of this application, the aforementioned mixed radiation source may include a gamma radiation source and a neutron radiation source.

[0090] The processor obtains a prepared gamma-ray source from the target nuclide irradiator and controls the gamma-ray source to be placed within a certain distance from the neutron converter. This causes the gamma rays emitted by the gamma-ray source to irradiate the neutron converter, producing a neutron source, thus generating a mixed radioactive source. The nuclear reaction here can be a (γ, n) reaction. It should be noted that generating a neutron source in the environment where the gamma-ray source emits gamma rays effectively produces a mixed radioactive source.

[0091] In this embodiment, the gamma radiation source used to prepare the hybrid radioactive source needs to meet a preset radiation intensity condition. Only under this condition can the gamma rays emitted by the gamma radiation source irradiate the neutron converter to generate a neutron radiation source. Optionally, the preset radiation intensity condition may include a specific radiation intensity value, which may be determined based on historical experience or according to the requirements for preparing the hybrid radioactive source. That is, during the preparation of the gamma radiation source, the target nuclide irradiator needs to meet a second gamma radiation condition, whereby the radiation intensity value of the target nuclide irradiator is equal to the specific radiation intensity value.

[0092] Since the target radioactive sources required for well logging (i.e., the mixed radioactive source and the gamma radioactive source) are different radioactive sources, and the gamma radioactive source used in preparing the mixed radioactive source can be understood as an intermediate product and the target product, the specific radiation intensity value corresponding to the gamma radioactive source used in preparing the mixed radioactive source required for well logging is different from the target radiation intensity value corresponding to the gamma radioactive source used in directly preparing the gamma radioactive source required for well logging.

[0093] In another embodiment, if the radioactive source is a neutron radioactive source, the method further includes, after the preparation of the mixed radioactive source, shielding the gamma rays emitted by the gamma radioactive source to obtain a neutron radioactive source from the mixed radioactive source.

[0094] It should be noted that if the radioactive source required for well logging is a neutron radioactive source, after the mixed radioactive source is prepared, a pure neutron radioactive source can be separated from the mixed radioactive source. Specifically, the processor can control the mechanical device to add a gamma shield (such as bismuth or lead) to the outside of the gamma radioactive source to shield the gamma rays released by the gamma radioactive source in the neutron converter, thereby obtaining a relatively pure neutron radioactive source in the mixed radioactive source.

[0095] If the radioactive source is a mixed radioactive source or a neutron radioactive source, then the gamma radioactive source used to generate the mixed radioactive source has a radiation energy value greater than the reaction threshold energy for the nuclear reaction to be generated by the neutron converter.

[0096] In the embodiments of this application, since the hybrid radioactive source or neutron radioactive source is prepared based on the gamma radioactive source, if a neutron radioactive source that meets the requirements of well logging applications is to be prepared, a gamma radioactive source with a radiation energy value greater than the reaction threshold energy of the neutron converter to generate nuclear reactions can be prepared first. This ensures that the gamma rays generated by the gamma radioactive source excite the nuclear reactions of the working nuclides in the neutron converter.

[0097] Optionally, the target working nuclide in the neutron converter can be heavy water (working nuclide is...). 2 H) or beryllium (working nuclide is ... 9 Be). In the process of preparing a neutron radiation source, indium is used as the target nuclide irradiator, and photoneutrons generated by a 9MeV / 900W electron accelerator are used to irradiate indium (that is, indium is inserted into beryllium or heavy water), resulting in a yield greater than 10. 7 A neutron radiation source with n / s can produce neutrons with engineering applications. For example... Figure 7 This is a schematic diagram showing the positional relationship of indium inserted into beryllium.

[0098] In practical applications, a neutron converter (containing a working nuclide) is excited by gamma rays from a gamma radiation source γ. 2 H or 9Be) undergoes a nuclear reaction to produce a neutron radioactive source n. The corresponding formula for the nuclear reaction is given by equation (2), i.e.:

[0099] (2);

[0100] Among them, E γ The value represents the gamma ray energy, p represents the proton produced by the nuclear reaction, and 2α represents the two alpha particles produced by the nuclear reaction. In addition, the above 2.223 MeV and 1.67 MeV both represent the reaction threshold energy of the nuclear reaction.

[0101] The technical solution in this application embodiment can obtain a prepared gamma radioactive source through a target nuclide irradiator; irradiate a neutron converter with the gamma radioactive source until the neutron converter meets the mixed radiation conditions to obtain a mixed radioactive source; the mixed radioactive source prepared by this method can not only meet the well logging requirements, but also ensure that the lifetime of the prepared mixed radioactive source is fixed and relatively short. After the application of the mixed radioactive source is completed, the radioactivity of the mixed radioactive source will disappear in a very short time and drop to a safe range, which greatly reduces the risk of uncontrolled radioactive source, thereby avoiding radioactive accidents to a certain extent, reducing the incidence of radioactive accidents, and improving personal safety.

[0102] In practical applications, the application requirements of different radioactive sources for well logging may vary depending on the specific needs of the source. Therefore, it is necessary to select different raw materials to prepare different radioactive sources that meet the application requirements of well logging. The process of obtaining the raw materials for preparing radioactive sources is described below. In one embodiment, the application requirements of well logging include the logging duration and the radiation energy value of the radioactive source required for logging. The process of obtaining the target nuclide irradiator according to the application requirements of well logging in S100 above may include: selecting at least one working nuclide from a preset irradiator material library that meets the logging duration and the radiation energy value required for logging, thereby obtaining the target nuclide irradiator.

[0103] Specifically, the logging duration mentioned above can be estimated data. In this embodiment, the logging duration can be approximately equal to the half-life of the prepared radioactive source. Optionally, the irradiant material library may include identification information of multiple different working nuclides, identification information of the radioactive sources corresponding to each working nuclide, the half-life of the radioactive sources corresponding to each working nuclide, the radiation energy value of the radioactive sources corresponding to each working nuclide, and the correspondence between these information.

[0104] It's important to note that once the working nuclide in the target irradiation body is determined, the energy value and half-life of the radiation produced by the corresponding radioactive source are fixed. Only the irradiation duration varies, resulting in different radiation intensity values. The radiation energy value of the radioactive source must match the response range of the logging equipment. Different radioactive sources required for logging will have different half-lives and radiation energy values. Optionally, the response range of the logging equipment can be understood as the logging range; matching the radiation energy value of the radioactive source with the response range of the logging equipment can be understood as the radiation energy value produced by the gamma radiation source being able to detect measurement indicators within the logging range.

[0105] The identification information of the radioactive source to be prepared can be determined according to the type of the radioactive source to be prepared. In this embodiment, the processor can select at least one working nuclide from a preset irradiant material library that meets the requirements of the logging duration and the radiation energy value of the radioactive source required for logging, based on the identification information of the radioactive source to be prepared, to obtain the target nuclide irradiant.

[0106] Meanwhile, in this embodiment, each working nuclide in the target nuclide irradiator used to prepare the radioactive source should possess the strength and hardness required by the harsh working conditions downhole, in order to avoid the radioactive source failing in a high-temperature and high-pressure environment. The working nuclide is initially non-radioactive.

[0107] like Figure 8 The diagram illustrates the process of placing a target nuclide irradiant selected from an irradiant material library into an irradiation chamber, then preparing a gamma radiation source using a radiation source preparation device, and finally lowering the gamma radiation source into the well. Figure 9 The diagram shows the process of placing a target nuclide irradiant selected from the irradiant material library into the irradiation chamber, then preparing a mixed radioactive source using a radioactive source preparation device, and finally lowering the gamma radioactive source into the well.

[0108] It should be noted that, in order to reduce the radiation dose to the human body, after the gamma radiation source is prepared, the neutron converter and the gamma radiation source can be simultaneously lowered into a well using a mechanical device. Then, underground, the gamma rays generated by the gamma radiation source excite the target working nuclide in the neutron converter to undergo a nuclear reaction, producing a neutron radiation source. Figure 9 The diagram illustrates the process of preparing a neutron radioactive source and its placement in a well using this method.

[0109] The technical solution in this application embodiment can select at least one working nuclide from a preset irradiant material library that meets the radiation energy value of the logging time and the required radioactive source for logging, and obtain the target nuclide irradiant. This method can select appropriate working nuclides according to different radioactive sources to be prepared, so that different working nuclides can be flexibly selected to prepare different types of radioactive sources required for logging, making the radioactive source preparation method more versatile and enriching the application scenarios of the radioactive source preparation method.

[0110] In one embodiment, this application also provides a method for preparing a radioactive source, the method comprising the following steps:

[0111] (1) Based on the logging duration and the radiation energy value of the radioactive source required for logging, at least one working nuclide that meets the logging duration and the radiation energy value of the radioactive source required for logging is selected from the preset irradiation body material library to obtain the target nuclide irradiation body; the target nuclide irradiation body includes at least one working nuclide.

[0112] (2) The electrons generated by the electron accelerator are accelerated by the electron accelerator of the radioactive source preparation equipment to obtain the electrons with the target electron energy value.

[0113] (3) Electrons are converted by the electron conversion target of the radioactive source preparation equipment to obtain radiation.

[0114] (4) The radiation is converted by a neutron converter to obtain photoneutrons.

[0115] (5) The target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment is irradiated with photoneutrons until the target nuclide irradiator meets the preset conditions, and the prepared radioactive source is obtained.

[0116] Among them, the steps in (5) above can be implemented in different ways depending on the different radioactive sources to be prepared:

[0117] Firstly, if the radiation source is a gamma radiation source, the preset conditions include gamma radiation conditions, and the steps in (5) above may include:

[0118] (51) The nuclear reaction is carried out between the ray of photoneutrons and the atomic nuclei in the target nuclide irradiation body until the ray intensity value of the target nuclide irradiation body is equal to the ray intensity value of the target ray, and the nuclear reaction is stopped to obtain the prepared gamma radiation source; the neutron converter is obtained by using a working nuclide with a reaction threshold energy lower than the preset threshold energy threshold.

[0119] The second approach, if the radiation source is a mixed radiation source, includes a second gamma radiation condition as a preset condition, and the steps in (5) above may include:

[0120] (52) Photoneutrons are generated by a neutron converter and used to irradiate the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the second gamma emission condition, thus obtaining a gamma radiation source;

[0121] (53) The gamma radiation source is combined with the neutron converter to obtain the prepared hybrid radiation source; the radiation intensity value of the gamma radiation source meets the preset radiation intensity condition.

[0122] Thirdly, if the radioactive source is a neutron radioactive source, then based on the second method described above, the steps in (5) above may also include:

[0123] (54) Shield the gamma rays emitted by the gamma radiation source to obtain a neutron radiation source from the mixed radiation source.

[0124] The specific execution process in (1) to (5) above can be found in the description of the above embodiments. The implementation principle and technical effect are similar, and will not be repeated here.

[0125] This application also provides a radioactive source preparation device, which includes a processor, an electron accelerator, an electron conversion target, and an irradiation cavity. The processor is used to implement the steps in any of the above-described radioactive source preparation methods through the electron accelerator, the electron conversion target, and the irradiation cavity.

[0126] Among them, such as Figure 1 The radioactive source preparation apparatus shown may further include a radiation shield to shield the radiation generated during the radioactive source preparation process from the electron conversion target, neutron conversion body, and irradiation cavity. Figure 1 A working nuclide is shown inside the irradiation cavity. Meanwhile, after the photoneutron irradiation within the irradiation cavity is completed, the neutron moderator can be removed.

[0127] In another embodiment, the radioactive source preparation apparatus includes a heavily charged particle accelerator and an irradiation cavity, and the processor is used to implement the steps in any of the embodiments of the above-described radioactive source preparation method through the heavily charged particle accelerator and the irradiation cavity. Optionally, the heavily charged particle accelerator can be a component in a neutron source of a heavily charged particle accelerator, which can be a deuterium-deuterium (DD) neutron source or a deuterium-tritium (DT) neutron source.

[0128] The heavy charged particle accelerator can produce deuterium nuclei with specific energies. These deuterium nuclei then react with deuterium or tritium within the accelerator to produce neutrons. These neutrons function the same as the photoneutrons described in the previous embodiment, only the names differ depending on the production environment. It should be noted that the nuclear reaction described above can be a DD reaction or a DT reaction, and the terms deuterium and tritium refer to components.

[0129] The radioactive source preparation equipment provided in this application embodiment can realize the radioactive source preparation method provided in any of the above embodiments. The implementation principle and technical effect are similar, and will not be described again here.

[0130] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0131] Based on the same inventive concept, this application also provides a radioactive source preparation apparatus for implementing the radioactive source preparation method described above. The solution provided by this apparatus is similar to the solution described in the above method; therefore, the specific limitations in one or more embodiments of the radioactive source preparation apparatus provided below can be found in the limitations of the radioactive source preparation method described above, and will not be repeated here.

[0132] In one embodiment, such as Figure 10 As shown, a radioactive source preparation apparatus is provided, comprising: an irradiant acquisition module 11 and a photoneutron irradiation module 12, wherein:

[0133] The irradiant acquisition module 11 is used to acquire the target nuclide irradiant according to the application requirements of well logging; the target nuclide irradiant includes at least one working nuclide.

[0134] The photoneutron irradiation module 12 is used to irradiate the target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment with photoneutrons until the target nuclide irradiator meets the preset conditions, thus obtaining the prepared radioactive source.

[0135] The radioactive source preparation apparatus provided in this embodiment can perform the above-described method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0136] In one embodiment, if the radiation source is a gamma radiation source, the preset conditions include a first gamma radiation condition; the photoneutron irradiation module 12 includes a first irradiation unit, wherein...

[0137] The first irradiation unit is used to generate photoneutrons through a neutron converter to irradiate the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the first gamma emission condition, thus obtaining a gamma radiation source; the neutron converter is obtained by using a working nuclide with a reaction threshold energy lower than a preset threshold energy threshold.

[0138] The radioactive source preparation apparatus provided in this embodiment can perform the above-described method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0139] In one embodiment, the first gamma radiation condition includes a target ray intensity value; the first irradiation unit is specifically used for:

[0140] The nuclear reaction is carried out by the photoneutron rays and the atomic nuclei in the target nuclide irradiation body until the radiation intensity of the target nuclide irradiation body is equal to the radiation intensity of the target ray, and then the nuclear reaction is stopped, thus obtaining the prepared gamma radiation source.

[0141] The radioactive source preparation apparatus provided in this embodiment can perform the above-described method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0142] In one embodiment, the radioactive source preparation apparatus further includes a photoneutron acquisition module, which is specifically used for:

[0143] Electrons generated by an electron accelerator in a radioactive source preparation device are accelerated to obtain electrons with the target electron energy value.

[0144] Electrons are converted into radiation by an electron conversion target in a radioactive source preparation device;

[0145] Radiation is converted into photoneutrons using a neutron converter.

[0146] The radioactive source preparation apparatus provided in this embodiment can perform the above-described method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0147] In one embodiment, if the radiation source is a hybrid radiation source, the preset conditions include a second gamma radiation condition; the photoneutron irradiation module 12 includes a second irradiation unit, wherein...

[0148] The second irradiation unit is used to generate photoneutrons through a neutron converter to irradiate the target nuclide irradiator in the radiation cavity until the target nuclide irradiator meets the second gamma emission condition, thus obtaining a gamma radiation source. The gamma radiation source is then combined with the neutron converter to obtain the prepared hybrid radiation source. The radiation intensity value of the gamma radiation source meets the preset radiation intensity condition.

[0149] The radioactive source preparation apparatus provided in this embodiment can perform the above-described method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0150] In one embodiment, the application requirements for well logging include the logging duration and the radiation energy value of the radiation source required for logging; the irradiation body acquisition module 11 is specifically used for:

[0151] Select at least one radiation energy value from a pre-defined irradiant material library that meets the logging duration and the required radioactive source for logging to obtain the target nuclide irradiant.

[0152] The radioactive source preparation apparatus provided in this embodiment can perform the above-described method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0153] Specific limitations regarding the radioactive source preparation apparatus can be found in the limitations regarding the radioactive source preparation method described above, and will not be repeated here. Each module in the aforementioned radioactive source preparation apparatus can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0154] In one embodiment, a computer device is provided, the internal structure of which can be shown in the following diagram. Figure 11 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computational and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The database stores a pre-defined library of irradiated materials. The network interface communicates with external endpoints via a network connection. When executed by the processor, the computer program implements a method for preparing a radioactive source.

[0155] Those skilled in the art will understand that Figure 11 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0156] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0157] The target nuclide irradiant is obtained according to the application requirements of well logging; the target nuclide irradiant includes at least one working nuclide.

[0158] The target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment is irradiated with photoneutrons until the target nuclide irradiator meets the preset conditions, thus obtaining the prepared radioactive source.

[0159] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0160] The target nuclide irradiant is obtained according to the application requirements of well logging; the target nuclide irradiant includes at least one working nuclide.

[0161] The target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment is irradiated with photoneutrons until the target nuclide irradiator meets the preset conditions, thus obtaining the prepared radioactive source.

[0162] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0163] The target nuclide irradiant is obtained according to the application requirements of well logging; the target nuclide irradiant includes at least one working nuclide.

[0164] The target nuclide irradiator placed in the radiation cavity of the radioactive source preparation equipment is irradiated with photoneutrons until the target nuclide irradiator meets the preset conditions, thus obtaining the prepared radioactive source.

[0165] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0166] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0167] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A radioactive source preparation device, characterized in that, The device includes a processor, an electron accelerator, an electron conversion target, and an irradiation cavity. The processor is used to implement a method for preparing a radioactive source using the electron accelerator, the electron conversion target, and the irradiation cavity. The method includes: At least one working nuclide that meets the requirements of logging duration and the radiation source energy value required for logging is selected from a pre-set irradiant material library to obtain a target nuclide irradiant; the target nuclide irradiant includes at least one working nuclide; If the radioactive source is a hybrid radioactive source, the electrons generated by the electron accelerator in the radioactive source preparation device are accelerated to obtain electrons with the target electron energy value; The electrons are converted by the electron conversion target of the radioactive source preparation device to obtain radiation. The radiation is converted into photoneutrons by a neutron converter; The target nuclide irradiator within the irradiation cavity is irradiated with photoneutrons until the radiation energy of the target nuclide irradiator exceeds the reaction threshold energy for nuclear reaction in the neutron converter, the half-life of the radiation from the target nuclide irradiator reaches a specific time threshold that meets the application requirements of well logging, and the radiation intensity of the target nuclide irradiator is equal to the specific radiation intensity value that causes the gamma rays emitted by the gamma radiation source to irradiate the neutron converter and generate a neutron radiation source, thus obtaining the gamma radiation source; the target nuclide irradiator includes indium, and the target working nuclide in the neutron converter includes heavy water or beryllium; the well logging duration is approximately equal to the half-life of the prepared radiation source; the radiation energy and half-life of the gamma rays emitted by the indium are fixed; The indium is controlled to be inserted into beryllium or heavy water, causing a nuclear reaction to occur when gamma rays emitted by the indium irradiate the beryllium or heavy water. This generates a neutron radioactive source, resulting in the prepared hybrid radioactive source; γ represents a gamma radioactive source. 2 H is the working nuclide of heavy water. 9 Be is the working nuclide of beryllium, p represents the proton produced in the nuclear reaction, 2α represents the two alpha particles produced in the nuclear reaction, and E γ The values ​​represent gamma ray energies; 2.223 MeV and 1.67 MeV both represent the reaction threshold energies at which nuclear reactions occur. The control mechanism installs the hybrid radioactive source into the downhole instrument and lowers it into the well. If the radioactive source is a neutron radioactive source, then after the mixed radioactive source is prepared, the gamma rays emitted by the gamma radioactive source are shielded, and the neutron radioactive source is obtained from the mixed radioactive source. The control mechanism installs the neutron radiation source into the downhole instrument and lowers it into the well.

2. The device according to claim 1, characterized in that, The method further includes: If the radiation source is a gamma radiation source, photoneutrons are generated by a neutron converter to irradiate the target nuclide irradiator in the irradiation cavity until the target nuclide irradiator meets the first gamma radiation condition, thus obtaining the gamma radiation source.

3. The device according to claim 1, characterized in that, The neutron converter is obtained by targeting a working nuclide with a reaction threshold energy lower than a preset threshold energy.

4. The device according to any one of claims 1-3, characterized in that, The specific radiation intensity value corresponding to the gamma radiation source used in preparing the hybrid radioactive source required for well logging is different from the target radiation intensity value corresponding to the gamma radiation source required for direct well logging.

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