A new type of embryonic biological stack for spatial multidirectional capture of high-energy heavy ions

Abstract

The application provides a new type of seed biological stack for spatial multidirectional capture of high-energy heavy ions, relates to the technical field of spatial passive individual horizontal radiation detection, and comprises seed fixing units, detection sheets in first, second and third directions, which can be combined in an arbitrary number, each seed fixing unit comprises a supporting column, a middle cross column and a hollow cross-shaped base, wherein the supporting column and the middle cross column are vertically fixed to four corners and the center of the hollow cross-shaped base respectively to form an integrated structure, the first direction detection sheet and the second direction detection sheet are installed in four installation spaces formed between the supporting column and the hollow cross-shaped base, and the third direction detection sheet is installed above the seed fixing unit. The application realizes detection of all heavy ions in six incident directions in three vertical dimensions XYZ of space, and can provide comprehensive radiation accumulation conditions of the tested material.

Description

Technical Field

[0001] This invention relates to the field of space passive individual horizontal radiation detection technology, and more particularly to a novel embryo-organism stack for capturing high-energy heavy ions in multiple directions in space. Background Technology

[0002] High-energy heavy ions in the space environment are a significant factor contributing to health risks during spaceflight. Studying the biological risks posed by high-energy heavy ions in space is a prerequisite for manned lunar and Mars missions. To investigate these biological risks, it is essential to accurately capture the quantity and energy of heavy ions in biological materials struck by them. Therefore, stacking probe materials and biological materials to form a sandwich structure is a crucial technique for this type of research; such a device is called a biostack.

[0003] The passive detection material used in the bio-stack is the CR-39 solid-state nuclear track detector, primarily composed of sheet-like polycarbonate. When struck by heavy ions, the chemical bonds at the impact site break, forming a damaged region. Under the influence of acidic or alkaline solutions, the etching rate at the damaged site is higher than that at undamaged sites, resulting in the formation of a track. After calibration, the energy of the impacting particle can be calculated. This type of detector can only detect heavy ions perpendicular to the normal and at a certain angle of incidence.

[0004] In biological studies at the individual level, plant seeds are generally used as biological materials. Rice seeds are a commonly used model organism in biological research; each rice seed can be considered an individual, and therefore can be used to study the individual-level biological effects of high-energy heavy ions in space. The active site of a rice seed is the rice embryo, and the projection of the embryo onto a nearby detector plate indicates the location of the heavy ion track to be read.

[0005] The rice seed embryo is a three-dimensional structure. Heavy ion tracks in space can potentially enter in the X, Y, and Z directions. Because the biological stack mounted on the spacecraft experiences varying degrees of shielding in different directions, the energy and quantity of heavy ion tracks in each direction are affected. Passive radiation detection materials for acquiring heavy ion tracks typically use the CR-39 solid-state nuclear track detector, which can detect heavy ion tracks incident at a certain angle in one direction. Its maximum detectable angle is determined by the etching scheme used in actual operation. Traditional biological stacks generally employ a layer of biological material and a layer of detector material. This setup can only detect heavy ion tracks from the detector's normal direction, with an actual detection efficiency of approximately one-third of all heavy ions. After flight, the location of heavy ion tracks generally relies on scanning or projection followed by manual identification, inevitably introducing subjective errors.

[0006] In summary, existing bio-stacking devices have two major drawbacks: 1. They cannot fully acquire heavy ion tracks of biological materials, and only detect one direction for each biological material; 2. They cannot accurately locate the projection center of the biological material on the detection surface, especially when there are multiple detection directions, as traditional bio-stacking devices lack multi-directional positioning capabilities. Summary of the Invention

[0007] To address the aforementioned technical problems of existing bio-stacking devices failing to fully acquire heavy-ion tracks from biological materials, only detecting one direction for each biological material and lacking accurate positioning of the projection center of the biological material on the detection surface, thus lacking multi-directional positioning capabilities, this invention provides a novel embryo-bio-stacking device for capturing high-energy heavy ions in multiple spatial directions. This invention primarily achieves heavy-ion incident detection of embryos in three spatial dimensions by adding installation positions that meet the detection requirements of solid-state nuclear track detectors.

[0008] The technical means employed in this invention are as follows: A novel seed-embryo bio-stacking system for capturing high-energy heavy ions in multiple spatial directions includes seed fixing units that can be combined in any number, as well as a first-direction detector, a second-direction detector, and a third-direction detector. Each seed fixing unit comprises an integrated structure consisting of a support column, a central cross column, and a hollow grid base. The first-direction detector and the second-direction detector are installed in four installation spaces formed between the hollow grid base and the support column. The third-direction detector is installed over the seed fixing unit.

[0009] Furthermore, there are four supporting columns, which are vertically fixed to the edges of the four corners of the hollow grid base. The middle cross column is vertically fixed to the center of the hollow grid base, and the edge of the middle cross column is flush with the edge of the hollow grid base to form a mounting base.

[0010] Furthermore, the first direction and the second direction are the X direction and the Y direction, respectively, and the third direction is the Z direction. The X-direction detector and the Y-direction detector are respectively installed in the installation space formed between the hollow grid base of the seed fixing unit and the two supporting columns on the same side. The Z-direction detector is covered and installed on top of any number of seed fixing units to form a biological stack.

[0011] Furthermore, the space between the cross-shaped column and the supporting column is used to accommodate rice seeds, which are fixed in the space with glue.

[0012] Furthermore, the outer side of the supporting column is curved to facilitate adaptation to an external container, which is a container with rounded inner corners or a right-angled rectangle.

[0013] Furthermore, the connection between the bottom side of the supporting column and the hollowed-out grid base has an arc-shaped protrusion, which is used to increase structural strength and restrict the seed direction.

[0014] Furthermore, the hollowed-out area of ​​the hollowed-out grid base is an elliptical bottom hole, which is used to fix the bottom of the seed and restrict the direction of the seed.

[0015] Compared with the prior art, the present invention has the following advantages: 1. The localization and detection of multi-directional heavy ions in space on rice seed embryos, a biomaterial, were realized; 2. By adding installation positions that meet the detection requirements of solid-state nuclear track detectors, heavy ion incident detection of embryos in three spatial dimensions was achieved; 3. This invention enables the detection of all heavy ions in three spatial dimensions (XYZ) and six incident directions, increasing the heavy ion detection coverage by 3 times and providing comprehensive information on the cumulative radiation of the test material. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the biological stacked structure of the present invention.

[0018] Figure 2 This is the main view of the unit structure in this invention.

[0019] Figure 3 This is a three-dimensional schematic diagram of the unit structure in this invention.

[0020] Figure 4 This is a schematic diagram showing the installation positions of the X and Y direction detectors in this invention.

[0021] Figure 5 This is an assembly diagram of this embodiment.

[0022] In the diagram: 1. Supporting column; 2. Central cross column; 3. Hollowed-out grid base; 4. X-direction detection plate; 5. Y-direction detection plate; 6. Z-direction detection plate. Detailed Implementation

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0026] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0027] like Figure 1-3As shown, this invention provides a novel seed-embryo bio-stacking system for capturing high-energy heavy ions in multiple spatial directions. It includes seed fixing units that can be combined in any number, as well as X-direction, Y-direction, and Z-direction detectors. Depending on the application requirements, there can be one or multiple seed fixing units. Each unit comprises an integrated structure consisting of four edge-fan-shaped support columns 1, a central cross column 2, and a hollow grid base 3. It is made entirely of aluminum and has no movable or detachable parts. The support columns 1 are fixedly installed at the edges of the four corners of the hollow grid base 3. The central cross column 2 is located at the center of the hollow grid base 3, and its edge is flush with the edge of the hollow grid base 3 to form a mounting base. The X-direction detector 4 and Y-direction detector 5 are installed in the mounting space formed between the mounting base and the two support columns 1. The Z-direction detector 6 is installed above the entire bio-stacking structure to form a three-dimensional bio-stacking system.

[0028] The space between the central cross-shaped column 2 and the supporting column 1 is used to accommodate rice seeds. The rice seeds are fixed in the installation position using PVAL. After the detector plate and rice seeds are installed, the sides of every two rice plants share a single detector plate plane for X and Y direction detection. A Z-direction detector plate 6 is placed over the seed in the Z direction for Z-direction detection, enabling detection in all three directions of the rice embryo. The X and Y direction detector plates are adhered to the installation surface using adhesive.

[0029] The outer edge of the central cross-shaped column 2 is flush with the hollowed-out grid base 3, forming a mounting base for mounting a solid-state nuclear track detector; The edge support column 1 has an outer arc surface, which can be adapted to the inner rounded corner mounting groove or the right angle mounting groove; The connection between the inner bottom side of the edge support column 1 and the hollow grid base 3 has an arc-shaped protrusion, which is used to increase the structural strength and restrict the seed direction; The bottom of the hollowed-out grid-shaped base has three hollowed-out sections with oval-shaped bottom holes for fixing the bottom of the seeds. The central cross-shaped column 2 and the edge support column 1 are of equal height, forming the mounting plane for the top solid-state nuclear track detector. The entire mechanical structure is machined as a single piece, with no moving parts.

[0030] The dimensions of this structure can be modified according to the type and size of the seeds. By adjusting the size of the bottom hollow grid base 3 and the height of the edges and the central cross pillar 2, it is suitable for any type of plant seed material with the embryo located at one end of the seed.

[0031] This invention can be applied to the plant sample experimental unit of the sample life support subsystem of the extravehicular radiation biology exposure experimental device on the space station, the plant gravity experimental unit of the variable gravity experimental cabinet on the space station, or any other satellite, spacecraft, space shuttle, or other type of spacecraft that can provide the conditions for carrying out the experiment (sample life protection conditions). It is mainly used to carry out exposure experiments on rice seeds in space. It can provide high-energy heavy ion data in all directions to accurately determine the radiation dose received by rice seeds, and provide a research basis for subsequent biological experiments.

[0032] Taking space experiments as an example, rice seeds are exposed to high-energy heavy ions and low-energy radiation from sources such as GCR (galactic cosmic rays), solar proton events, and the South Atlantic Anomaly. Measuring low-energy radiation is relatively simple, relying on a TLD detector plate mounted on the structure. Measuring heavy ions is more difficult, requiring a solid nuclear track detector to be placed in close contact with the biological material, and then obtaining the projection of the biological material onto the solid nuclear track detector. Currently reported biological stacks, including all similar biological stacks launched by the United States, Europe, and Russia in the 1970s-1990s, as well as those from China's Shenzhou 3, Shijian-10, and the Chinese space station, regardless of whether they use nuclear emulsion or CR-39 for radiation detection, have only achieved detection in one direction in space. While the accuracy of detecting only one direction is acceptable for biological research when using tiny seeds in spaceflight experiments, when using micrometer-sized biological samples such as rice embryos, the previous methods of measuring the heavy ion absorbed dose from only one side of the biological stack lead to an uncertainty of over 60%.

[0033] Usage Example 1: Application procedure of the device in the experimental cabinet of the Chinese space station. Rice seeds marked with a marker are installed in one of the four compartments of the unit of this invention using tweezers, with the embryo facing outwards and the length and width of the embryo matching the installation position. After the seed is installed, a small amount of PVAL glue is pushed into the gap between the central cross post 2 and the seed using a disposable syringe, and then allowed to dry at room temperature.

[0034] Take a solid nuclear track detector (hand-cut) suitable for the installation location. Use a steel needle to apply a small amount of 414C silicone rubber to the mounting bases on both sides of the device. Then, use tweezers to install the solid nuclear track detector on the T-shaped mounting base and dry it on a clean bench. Each unit can install 4 detector strips to detect 4 seeds in two directions. Install the fully fixed units in the base of the experimental unit, in groups of 9, and cover them with Z-direction detector strip 6 for detecting the Z direction. Compared with other biological stacks, the addition of detector strips in two directions increases the detection coverage of heavy ions by 200%. After the device is fixed, it can be used for spaceflight and experiments can be carried out in a variable gravity cabinet or an extravehicular sample life support subsystem.

[0035] Upon returning to Earth, the device was activated, and the Z-direction probe 6 was fixed and scanned. Then, all units were removed, and each direction was scanned individually to obtain high-precision images. Image processing software was used to mark the precise location of the rice embryos, and subsequent readings were performed.

[0036] Example of use 2: A three-dimensional rice stack is applied to a recoverable satellite. Several stacks of rice can be installed in a group within a sample container with a top plate. The rounded corners of the supporting pillar 1 can leave gaps with right-angle boundaries to be filled with adhesive material. After installing the seeds with the X-direction detector 4 and Y-direction detector 5, and covering them with the top Z-direction detector 6, the cumulative dose of three-dimensional heavy ion incident radiation in space can be detected. After installation, studies on the heavy ion radiation received by rice embryos during spaceflight can be conducted. After the satellite returns to Earth, the recovery procedures are the same as in Example 1. The total absorbed radiation dose received by the test organism is obtained by marking the position of each embryo in each direction.

[0037] 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 the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A novel embryo-organic stack for capturing high-energy heavy ions in multiple directions in space, characterized in that, It includes seed fixing units that can be combined in any number, as well as a first direction detection plate, a second direction detection plate, and a third direction detection plate. Each seed fixing unit includes an integrated structure consisting of a support column, a central cross column, and a hollow grid base. The first direction detection plate and the second direction detection plate are installed in the four installation spaces formed between the hollow grid base and the support column. The third direction detection plate is installed on top of the seed fixing unit.

2. The novel embryo-organic stack for capturing high-energy heavy ions in multiple directions in space according to claim 1, characterized in that, The support columns consist of four pillars, which are vertically fixed to the edges of the four corners of the hollow grid base. The central cross pillar is vertically fixed to the center of the hollow grid base, and the edge of the central cross pillar is flush with the edge of the hollow grid base to form a mounting base.

3. The novel embryo-organic stack for capturing high-energy heavy ions in multiple directions in space according to claim 1, characterized in that, The first direction and the second direction are the X direction and the Y direction, respectively, and the third direction is the Z direction. The X-direction detector and the Y-direction detector are respectively installed in the installation space formed between the hollow grid base of the seed fixing unit and the two supporting columns on the same side. The Z-direction detector is installed on top of any number of seed fixing units to form a biological stack.

4. The novel embryo-organic stack for capturing high-energy heavy ions in multiple directions in space according to claim 1, characterized in that, The space between the cross-shaped uprights and the supporting uprights is used to hold rice seeds, which are then fixed in this space with glue.

5. The novel embryo-organic stack for capturing high-energy heavy ions in multiple directions in space according to claim 1, characterized in that, The outer side of the supporting column is curved to facilitate adaptation to the external container, which is a container with rounded inner corners or a right-angled rectangle.

6. The novel embryo-organic stack for capturing high-energy heavy ions in multiple directions in space according to claim 1, characterized in that, The connection between the bottom side of the supporting column and the hollowed-out grid base has an arc-shaped protrusion, which is used to increase structural strength and restrict the direction of the seed.

7. The novel embryo-organic stack for capturing high-energy heavy ions in multiple directions in space according to claim 1, characterized in that, The hollowed-out grid base has an oval-shaped bottom hole, which is used to fix the bottom of the seed and restrict the seed's orientation.

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