Convenient device and method for field < 13 > C isotope labeling

Abstract

The invention relates to the technical field of isotope tracer technology, and discloses a convenient device and method for field < 13 > C isotope labeling, the convenient device for labeling comprises a cubic support, the cubic support is formed by assembling a plurality of transverse pipes and a plurality of vertical pipes, the cubic support is covered with a plastic film, and the plastic film is arranged on the cubic support. The cubic support and the plastic film are assembled into the isotope labeling box, the interior of the cubic support is communicated, an air inlet and an edge pressing assembly are formed in the pipe wall of one vertical pipe, the edge pressing assembly comprises an internal edge pressing square frame and an external edge pressing square frame, the external edge pressing square frame adopts a splicing design, and the internal edge pressing square frame is arranged on the cubic support in a sleeving manner. According to the convenient device and method for field < 13 > C isotope labeling, the labeling box can be formed in a flexible disassembly mode, the transportation and movement requirements under the scene of field sample plot replacement and the like are met, the size of the labeling box can be flexibly adjusted in the field scene, and the convenient device and method are suitable for various field ecological system in-situ labeling experiments.

Description

Technical Field

[0001] The present invention relates to the technical field of isotope tracing, and specifically to a convenient device and method for 13 C isotope labeling in the wild. Background Art

[0002] Currently 13 C labeling is mainly carried out through a labeling chamber. The chamber is usually made of a transparent material (such as polycarbonate) to ensure sufficient light. By sealing the chamber and equipped with a liquid filling port or an air inlet and an air outlet to control the gas composition. Inside the chamber, there are sensors for monitoring temperature, humidity and CO2 concentration. The labeling principle is to inject 13 C-labeled CO2 ( 13 CO2) or inject concentrated sulfuric acid (H2SO4) into Na 13 CO3 placed in the labeling chamber in advance to react to generate 13 CO2 (Na2 13 CO3 + H2SO4 → Na2SO4 + H2O + 13 CO2). Plants absorb and fix this labeled carbon during photosynthesis. Subsequently, the collected plant, soil and gas samples are analyzed and measured for the 13 C / 12 C ratio and carbon content by an isotope ratio mass spectrometer (IRMS, Isotope Ratio Mass Spectrometry) to trace the migration and storage of carbon. Considering the portability and labeling effectiveness of field operations, most current relevant researchers use the method of dropping concentrated sulfuric acid (H2SO4) into Na 13 CO3 placed in the labeling chamber in advance to react to generate 13 CO2 for labeling. Currently 13 C isotope labeling chambers are made of materials such as transparent acrylic plates, and are divided into a base and an upper cover. The base is driven into the grass plot to be labeled in advance, and then the upper cover is placed and sealed with water to form a closed cubic space, and 13 C isotope labeling operations are carried out within this closed space.

[0003] Currently, the existing labeling chambers made of transparent acrylic plates are more suitable for indoor experiments. When used in the field environment, their surfaces are easily damaged during the labeling process, affecting the light transmission effect, with poor reusability, and their volumes are relatively fixed. It is difficult to carry multiple labeling chambers at one time for isotope labeling, and it is not suitable for changing multiple field plots. Summary of the Invention

[0004] (1) Technical Problem to be Solved

[0005] In view of the deficiencies of the prior art, the present invention provides a convenient device and method for 13 13C isotope labeling, which solves the problems that the surface of the traditional labeling box is prone to damage during the labeling process when used in the field environment, has poor reusability, and has a relatively fixed volume, making it difficult to carry multiple labeling boxes at one time for isotope labeling, and is not suitable for replacing multiple field plots.

[0006] (2) Technical solution

[0007] To achieve the above object, the present invention provides the following technical solution: A convenient device for 13 13C isotope labeling, including a cubic support, which is assembled by a plurality of horizontal tubes and a plurality of vertical tubes. A plastic film is covered on the cubic support, and the cubic support and the plastic film are assembled into an isotope labeling box. The inside of the cubic support is communicated, and an air inlet is opened on the tube wall of one of the vertical tubes;

[0008] A crimping component, which includes an internal crimping square frame and an external crimping square frame. The external crimping square frame adopts a splicing design, and the internal crimping square frame is sleeved on the cubic support;

[0009] An isotope generating device, which is installed on the vertical side of the cubic support for convenient addition of chemical drugs, and can maintain the airtightness inside the isotope labeling box when injecting chemical drugs;

[0010] An air circulation device, which is installed at a position diagonal to the isotope generating device on the cubic support. Through the internally connected cubic support, the labeled gas can be quickly mixed in the isotope labeling box.

[0011] Preferably, a hemispherical sealing cover is provided at the upper end of the vertical tube, a tapered structure is provided at the lower end of the vertical tube, four threaded tubes are fixed on the tube wall of the vertical tube, the four threaded tubes are grouped in pairs, and the center lines of the two threaded tubes in each group are perpendicular to each other. One group of the threaded tubes is vertically fixed at the sealing cover above the vertical tube, and the other group of the threaded tubes is vertically fixed on the tube wall of the vertical tube above the constriction. Nuts are fixedly connected to the inner edges of the two pipe orifices of the horizontal tube, and the nuts are matched with the tube walls of the threaded tubes.

[0012] Preferably, a plurality of exhaust holes are opened on the tube walls of the plurality of vertical tubes, and the plurality of exhaust holes all face the vertical center line of the cubic support. The air inlet opened on the tube wall of the vertical tube is used for the air flow conveyed by the air circulation device to be discharged from the plurality of exhaust holes.

[0013] Preferably, the inner edge pressing square frame of the edge pressing component is welded by steel bars, and the side length is two centimeters longer than the side length of the cubic support. The outer edge pressing square frame is spliced by two identical C-shaped bars, and the lower ends of the C-shaped bars are fixedly connected with pressing plates of the same structure. Two fixing seats are fixedly connected to the pressing plate of one of the C-shaped bars, and two mating inserting bars are fixedly connected to the pressing plate of the other C-shaped bar. A hand-tightening bolt is connected to the fixing seat. Nail holes are provided at the four corners of the outer edge pressing square frame, and wedges are inserted into the nail holes.

[0014] Preferably, the isotope generating device includes a fixing frame. One side of the fixing frame is fixed on the pipe wall of one of the vertical pipes. One side of the fixing frame is fixedly connected with a rectangular sleeve. A rectangular sleeve is sleeved in the rectangular sleeve. One side of the rectangular sleeve is fixedly connected with a sealing plate. A rubber seat is fixedly connected in the rectangular sleeve. A medicine storage pipe is arranged in the rubber seat. A round opening is opened at the upper end of the rectangular sleeve. A rubber plug is arranged in the round opening. The lower end of the rubber plug extends into the upper end pipe orifice of the medicine storage pipe and is fixedly connected with a diversion pipe. The diversion pipe is composed of an upper cone and a lower cone. A flow limiting hole is arranged at the connection of the upper cone and the lower cone. The lower end of the lower cone is provided with a conical bottom. A plurality of liquid outlet holes are obliquely opened at the conical bottom. An air outlet is arranged on one side of the medicine storage pipe.

[0015] Preferably, a rubber ring is fixedly connected in the air outlet. A right-angle elbow pipe is sleeved in the rubber ring. A clamping seat is arranged on one side of the rubber seat. An air cylinder is clamped in the clamping seat. The upper end of the air cylinder is hermetically connected with a bottle cap. One end of the right-angle elbow pipe penetrates through the bottle cap and extends into the air cylinder. An air outlet pipe is installed on the other side of the bottle cap.

[0016] Preferably, a magnetic sealing ring that can be attracted to the fixing frame is fixedly connected to one side of the sealing plate. A rubber ring is embedded in the inner edge of one end pipe orifice of the rectangular sleeve. The rubber ring is of a hollow structure and is sleeved with the side wall of the rectangular sleeve. A rectangular groove is arranged on one side of the fixing frame.

[0017] Preferably, the air circulation device includes a wind box. One side of the wind box is fixedly connected with a C-shaped clamping ring. The C-shaped clamping ring is clamped on the pipe wall of the vertical pipe and is provided with an opening that matches the air inlet. A partition plate is fixedly connected in the wind box. The partition plate divides the inside of the wind box into a drying chamber and an air inlet chamber. One side of the wind box is fixedly connected with a first fan. The air outlet end of the first fan faces the air inlet and the opening.

[0018] The upper end of the bellows is provided with a medicine placement opening, a sealing cover is installed at the medicine placement opening, a second fan is installed at the upper end of the sealing cover, a plurality of air inlets are arranged on the side wall of the bellows, mesh plates are fixedly connected in the plurality of air inlets, two temperature and humidity sensors are installed at the air inlets, two positioning rings are fixedly connected to the pipe wall of the vertical pipe, and positioning protrusions cooperating with the opening areas of the C-shaped snap rings are correspondingly arranged on the positioning rings.

[0019] The present invention also provides a method for 13 C isotope labeling, which is applicable to conducting field 13 C isotope in-situ labeling experiments on grasslands, small trees, small shrubs, and wetland ecosystems. The specific steps are as follows;

[0020] Step 1: Make an internal cubic bracket. Screw multiple horizontal pipes onto the threaded pipes on multiple vertical pipes to form a cubic bracket, and install an isotope generating device and an air circulation device diagonally.

[0021] Step 2: In the plot to be labeled, select an area of about one square meter. Place the cubic bracket above the labeled plants. Insert the vertical pipes of the cubic bracket into the soil using a drawstring until the bottom edge is flush with the ground to complete the fixation of the cubic bracket. Clear a buffer zone of about 10 cm along the outer periphery of the bottom edge to facilitate subsequent plastic film sealing.

[0022] Step 3: Cover the cubic bracket with a transparent plastic film, and smooth and press the transparent plastic film along the top surface and vertical edges of the cubic bracket from top to bottom with the internal edge pressing frame.

[0023] Step 4: Put on the external edge pressing frame, fix the four corners of the external edge pressing frame to the ground with wedges, and then firmly fix the extended transparent plastic film to the ground to complete the assembly of the isotope labeling box.

[0024] Step 5: Use a syringe needle to quantitatively inject 5 ml of concentrated sulfuric acid into the medicine storage tube in the isotope generating device. The concentrated sulfuric acid reacts with Na2 13 CO3 in the medicine storage tube to generate 13 CO2 gas for labeling. Repeat this step 3 times at 1 hour, 2 hours, and 4 hours after the first labeling is completed to complete the labeling process.

[0025] Step 6: 6 hours after the first labeling is completed, insert a syringe into the transparent plastic film, collect 100 ml of gas and put it into an air bag for preservation and subsequent index determination. Remove the labeling equipment, and then collect plant, soil, and lye (NaOH solution) samples.

[0026] Preferably, in step three, when the ambient temperature is relatively high, a double-layer plastic film is covered. The innermost layer is first fixed by an internal edge-pressing square frame, and then the outermost layer of plastic film is covered and the double-layer plastic film is fixed by an external edge-pressing square frame. At this time, a three-dimensional cavity is formed between the inner and outer plastic films. An air pipe connector is fixed on the outermost layer of plastic film to connect to an air pump, and an exhaust port with the same diameter as the air pipe connector is opened on the corresponding side. The air pump is used to convey gas to make the gas in the cavity flow, so as to achieve the effect of reducing the temperature inside the isotope labeling box.

[0027] (III) Beneficial effects

[0028] Compared with the prior art, the present invention provides a convenient device and method for field 13 C isotope labeling, having the following beneficial effects:

[0029] 1. The cube bracket designed and manufactured in the present invention forms a cube bracket by screwing multiple horizontal tubes onto the threaded tubes of multiple vertical tubes, and an isotope generating device and an air circulation device are installed diagonally. Compared with traditional fixed equipment, it can be conveniently disassembled and carried, saving a large amount of space. Multiple groups can be carried at one time to perform labeling operations on different positions or plants. At the same time, by setting the cube bracket into a structure with internal communication, the air circulation device can be used to make the labeled gas flow back into the isotope labeling box from four directions and blow near the measured plants, enabling the gas in the isotope labeling box to be quickly mixed and improving the labeling quality.

[0030] 2. For the isotope generating device of the present invention, a syringe with a needle is directly used to puncture the rubber stopper. After passing through the rubber stopper, concentrated sulfuric acid can be pushed into the diversion tube. The upper cone of the diversion tube accommodates more concentrated sulfuric acid, and then it slowly drips into the lower cone through a flow-limiting hole. At this time, the concentrated sulfuric acid drips from multiple liquid outlet holes, so that the concentrated sulfuric acid can slowly contact with the Na2 13 CO3 medicine to produce a chemical reaction, avoiding a violent reaction caused by adding too much concentrated sulfuric acid to the Na2 13 CO3 medicine at one time. The labeled gas generated during the reaction process enters the gas cylinder through a right-angle elbow and contacts with sodium hydroxide solution. In this way, the sodium hydroxide solution can be used to absorb the impurities in the gas, and then the relatively pure labeled gas is discharged from the air outlet pipe into the isotope labeling box.

[0031] 3. During the design process of this technical solution, a flexible and detachable cube bracket is made of common durable pipes, and assembled with an economical, practical and recyclable plastic film to form an isotope labeling box. The production of this labeling box does not use a large amount of heavy main materials, so it is relatively light in weight and convenient to move. Using rigid pipes and plastic films, compared with traditional materials such as acrylic sheets, the produced product is strong and durable, and there is no problem of being easily damaged during movement. It is suitable for the transportation and movement requirements in scenarios such as changing sample plots in the wild. It is equipped with a sealing edge pressing frame made by the steel bar welding process, which is strong and durable and can be reused repeatedly. It can effectively ensure the sealing between the plastic film and the ground. The size of the labeling frame can be flexibly adjusted according to the applicable wild scenario, and it is suitable for in-situ labeling experiments in a variety of wild ecosystems. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A convenient device for 13 13C isotope labeling in the wild, the structural schematic diagram;

[0033] Figure 2 A convenient device for 13 13C isotope labeling in the wild, the structural schematic diagram of the cube bracket and the edge pressing component in the convenient device;

[0034] Figure 3 A convenient device for 13 13C isotope labeling in the wild, the structural schematic of the isotope generating device in the convenient device Figure 1 ;

[0035] Figure 4 A convenient device for 13 13C isotope labeling in the wild Figure 3 the structural schematic diagram at position A in the convenient device;

[0036] Figure 5 A convenient device for 13 13C isotope labeling in the wild, the structural schematic of the isotope generating device in the convenient device Figure 2 ;

[0037] Figure 6 A convenient device for 13 13C isotope labeling in the wild, the structural schematic diagram of the air circulation device in the convenient device;

[0038] Figure 7 A convenient device for 13 13C isotope labeling in the wild, the internal structural schematic diagram of the bellows in the convenient device;

[0039] Figure 8 A convenient device for 13Schematic diagram of the structure of the C-shaped clamp and the vertical tube in the convenient device for C isotope labeling;

[0040] Figure 9 A kind proposed by the present invention for use in the field 13 Schematic diagram of the structure of the second fan and the sealing cover in the convenient device for C isotope labeling;

[0041] Figure 10 A kind proposed by the present invention for use in the field 13 Schematic diagram of the structure of the vertical tube and the horizontal tube in the convenient device for C isotope labeling;

[0042] Figure 11 A kind proposed by the present invention for use in the field 13 Schematic diagram of the structure of the edge pressing assembly, vertical tube and horizontal tube after disassembly in the convenient device for C isotope labeling;

[0043] Figure 12 A kind proposed by the present invention for use in the field 13 Schematic diagram of the structure of the plastic film in the convenient device for C isotope labeling;

[0044] Figure 13 A kind proposed by the present invention for use in the field 13 Schematic diagram of the structure when using a double-layer plastic film in the convenient device for C isotope labeling;

[0045] Figure 14 A kind proposed by the present invention for use in the field 13 Schematic diagram of the structure of the external edge pressing square frame in the convenient device for C isotope labeling.

[0046] In the figure: 1. Cubic support; 2. Fixed frame; 3. Sealing plate; 4. External edge pressing square frame; 5. Internal edge pressing square frame; 6. Mouth binding; 7. Wedge; 8. Plastic film; 9. Horizontal tube; 10. Vertical tube; 11. Exhaust hole; 12. Second fan; 13. Positioning ring; 14. C-shaped clamp; 15. Bellows; 16. Magnetic sealing ring; 17. Rectangular sleeve; 18. Rectangular socket; 19. Rubber ring; 20. Bottle cap; 21. Outlet pipe; 22. Gas cylinder; 23. Card seat; 24. Right-angle elbow; 25. Rubber seat; 26. Medicine storage tube; 27. Diversion tube; 28. Rubber plug; 29. Upper cone; 30. Lower cone; 31. Liquid outlet hole; 32. Flow limiting hole; 33. Temperature and humidity sensor; 34. First fan; 35. Opening; 36. Air inlet; 37. Sealing cover; 38. Threaded pipe; 39. Nut; 40. Cavity; 41. Insertion strip; 42. Fixed seat; 43. Hand-tightening bolt; 44. Pressing plate. Detailed implementation mode

[0047] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0048] Embodiment 1: Refer to the attached Figure 1-14 , a convenient device for 13 C isotope labeling, which adopts an assembled three-dimensional framework. Compared with traditional fixed equipment, it can be easily disassembled and carried, saving a large amount of space. Multiple groups can be carried at one time to perform labeling operations on different positions or plants;

[0049] The main technical solutions of this convenient device include a cubic support 1, which is assembled by multiple horizontal tubes 9 and multiple vertical tubes 10. Here, 8 horizontal tubes 9 are required and 4 vertical tubes are equipped to form an octahedral 12-sided cube shape. The materials of the horizontal tubes 9 and the vertical tubes 10 can be common materials such as stainless steel tubes, engineering plastic tubes, alloy tubes, etc. A plastic film 8 is covered on the cubic support 1. The plastic film 8 uses a plastic film with good light transmittance, such as polyethylene (PE) film, polyvinyl chloride (PVC), etc., with good economy. The thickness of the film is 0.15 - 0.3 mm, preferably 0.2 mm, the light transmittance needs to reach 85% - 90%, and the haze is about 5% - 10%. While meeting the light transmittance requirements, it also has good puncture resistance. The cubic support 1 and the plastic film 8 are assembled into an isotope labeling box. The inside of the cubic support 1 is connected, and an air inlet 36 is opened on the wall of one of the vertical tubes 10. A hemispherical sealing cover is provided at the upper end of the vertical tube 10, which can prevent air leakage and avoid puncturing the plastic film 8 at the same time. A tapered structure of a collar 6 is provided at the lower end of the vertical tube 10. The collar 6 is tapered to facilitate inserting the assembled cubic support 1 into the ground for fixation. Four threaded tubes 38 are fixed on the wall of the vertical tube 10. The four threaded tubes 38 are grouped in pairs, and the center lines of the two threaded tubes 38 in each group are perpendicular to each other, that is, the included angle is 90°. One group of threaded tubes 38 is vertically fixed at the sealing cover above the vertical tube 10, and the other group of threaded tubes 38 is vertically fixed on the wall of the vertical tube 10 above the collar 6. Nuts 39 are fixedly connected to the inner edges of the two pipe orifices of the horizontal tube 9, and the nuts 39 cooperate with the walls of the threaded tubes 38. A plurality of exhaust holes 11 are opened on the walls of the plurality of vertical tubes 10, and all the plurality of exhaust holes 11 face the vertical center line of the cubic support 1. The air inlet 36 opened on the wall of the vertical tube 10 is used for the air flow conveyed by the air circulation device to be discharged from the plurality of exhaust holes 11;

[0050] Such as Figure 10As shown, after connecting the hollow threaded pipe 38 with the nut 39, the inside of the vertical pipe 10 and the horizontal pipe 9 can be made to communicate. When the air circulation device operates to generate gas, the gas in the isotope labeling box first enters the inside of the cube bracket 1 and then is discharged from the exhaust hole 11. Since there are 4 vertical pipes 10 provided on the cube bracket 1, it can flow back into the isotope labeling box from four directions and blow towards the vicinity of the plant to be measured, enabling the gas in the isotope labeling box to be quickly mixed and improving the labeling effect.

[0051] As Figure 1 , Figure 2 and Figure 14 shown, the adopted edge pressing assembly is divided into an inner and an outer part, including an inner edge pressing square frame 5 and an outer edge pressing square frame 4. The outer edge pressing square frame 4 adopts a splicing design. The inner edge pressing square frame 5 is sleeved on the cube bracket 1. The inner edge pressing square frame 5 of the edge pressing assembly is welded by steel bars and its side length is two centimeters longer than the side length of the cube bracket 1. When the inner edge pressing square frame 5 is sleeved on the cube bracket 1, it can well make the plastic film 8 adhere to the cube bracket 1 to form a regular isotope labeling box. The outer edge pressing square frame 4 is spliced by two identical C-shaped strips, and the lower ends of the C-shaped strips are fixedly connected with pressing plates 44 of the same structure. The pressing plates 44 have sufficient grounding area. When pressing the plastic film 8, it can effectively improve the sealing line and prevent the labeled gas inside the isotope labeling box from leaking. Two fixing seats 42 are fixedly connected to the pressing plate 44 of one C-shaped strip, and two mating inserts 41 are fixedly connected to the pressing plate 44 of the other C-shaped strip. A hand-tightening bolt 43 is connected to the fixing seat 42. Nail holes are provided at the four corners of the outer edge pressing square frame 4, and wedges 7 are inserted into the nail holes. The wedges 7 can firmly fix the outer edge pressing square frame 4 on the ground and press the plastic film 8. The plastic film 8 is covered in double layers. The innermost layer is first fixed by the inner edge pressing square frame 5, and then the outermost layer of the plastic film 8 is covered and the outer edge pressing square frame 4 is used to fix the double-layer plastic film 8. At this time, a three-dimensional cavity 40 is formed between the inner and outer plastic films 8. A tracheal joint is fixed on the outermost layer of the plastic film 8 to connect to an air pump (as Figure 13 shown by the dotted line in the figure), and an exhaust port with the same diameter as the tracheal joint is opened on the corresponding side. At this time, the air pump extracts the external gas into the cavity 40 between the double-layer plastic films 8, and the flowing cold air can effectively reduce the temperature inside the isotope labeling box, so that the internal temperature of the isotope labeling box can be maintained at a suitable labeling temperature.

[0052] When the present invention is in use, an internal cubic support 1 is fabricated. A plurality of transverse tubes 9 are screwed onto the threaded tubes 38 on a plurality of vertical tubes 10 to form the cubic support 1. The isotope generating device and the air circulation device are installed diagonally. Compared with traditional fixed devices, it can be conveniently disassembled and carried, saving a large amount of space. Multiple groups can be carried at one time to perform marking operations on different positions or plants. At the same time, by setting the cubic support 1 into a structure with internal communication, the air circulation device can be used to make the marking gas flow back into the isotope marking box from four directions and blow towards the vicinity of the plant to be measured, enabling the gas in the isotope marking box to be quickly mixed and improving the marking quality.

[0053] Embodiment 2: The difference from Embodiment 1 is as follows;

[0054] Referring to the appendix Figures 3-5 , in order to facilitate the staff to add drugs multiple times, this technical solution is provided with an isotope generating device. The isotope generating device is installed on the vertical side of the cubic support 1 for convenient addition of chemical drugs, and the sealing performance inside the isotope marking box can be maintained when injecting chemical drugs;

[0055] The adopted isotope generating device includes a fixed frame 2. One side of the fixed frame 2 is fixed on the pipe wall of one of the vertical tubes 10. One side of the fixed frame 2 is fixedly connected with a rectangular sleeve 17. A rectangular sleeve 18 is sleeved inside the rectangular sleeve 17. One side of the rectangular sleeve 18 is fixedly connected with a sealing plate 3. One side of the sealing plate 3 is fixedly connected with a magnetic sealing ring 16 that can be attracted to the fixed frame 2. A rubber ring 19 is embedded in the inner edge of one end of the rectangular sleeve 17. The rubber ring 19 is a hollow structure and is sleeved on the side wall of the rectangular sleeve 18. At this time, the sealing plate 3 and the rectangular sleeve 18 form a movable drawer structure. When it is opened, the rubber ring 19 provides sealing performance, and when it is closed, the rubber ring 19 and the magnetic sealing ring 16 jointly provide sealing performance, so that when adding drugs multiple times, the marking gas in the isotope marking box does not leak;

[0056] In addition, since the plastic film 8 is a whole plastic film with a side length of 2 meters, a rectangular groove is provided on one side of the fixed frame 2. When assembling the isotope generating device, a rectangular hole can be cut out on site along the rectangular groove using a tool, and the rectangular hole is pasted on the fixed frame 2 with transparent tape to ensure airtightness. A rubber seat 25 is fixedly connected inside the rectangular sleeve 18. A medicine storage tube 26 is arranged inside the rubber seat 25. The inside of the medicine storage tube 26 is used to store Na2 13CO3 medicine, a circular opening is provided at the upper end of the rectangular sleeve 18, a rubber stopper 28 is arranged in the circular opening, the lower end of the rubber stopper 28 extends into the upper end pipe orifice of the medicine storage tube 26 and is fixedly connected with a diversion tube 27. The diversion tube 27 is composed of an upper cone 29 and a lower cone 30. A flow limiting hole 32 is arranged at the connection of the upper cone 29 and the lower cone 30. The lower end of the lower cone 30 is provided with a conical bottom, and a plurality of liquid outlet holes 31 are obliquely arranged at the conical bottom. An air outlet is arranged on one side of the medicine storage tube 26. A rubber ring is fixedly connected in the air outlet, and a right-angled elbow 24 is sleeved in the rubber ring. A clamping seat 23 is arranged on one side of the rubber seat 25, and a gas cylinder 22 is clamped in the clamping seat 23. Sodium hydroxide solution is stored in the gas cylinder 22. By using the chemical reaction between sodium hydroxide and sulfur dioxide, the 13 sulfur dioxide gas volatilized from concentrated sulfuric acid in CO3 is removed. The upper end of the gas cylinder 22 is hermetically connected with a bottle cap 20. One end of the right-angled elbow 24 penetrates through the bottle cap 20 and extends into the gas cylinder 22. An air outlet pipe 21 is installed on the other side of the bottle cap 20.

[0057] In the isotope generating device of the present invention, a syringe with a needle is used to directly puncture the rubber stopper 28. After passing through the rubber stopper 28, concentrated sulfuric acid can be pushed into the diversion tube 27. The diversion tube 27 uses the upper cone 29 to accommodate more concentrated sulfuric acid, and then slowly drips into the lower cone 30 through the flow limiting hole 32. At this time, the concentrated sulfuric acid drips from the plurality of liquid outlet holes 31, so that the concentrated sulfuric acid can slowly react chemically with the Na2 13 CO3 medicine, avoiding violent reaction caused by adding too much concentrated sulfuric acid to the Na2 13 CO3 medicine at one time. The labeled gas generated during the reaction process enters the gas cylinder 22 through the right-angled elbow 24 and contacts with the sodium hydroxide solution. In this way, the sodium hydroxide solution can be used to absorb the impurities in the gas, and then the relatively pure labeled gas is discharged from the air outlet pipe 21 into the isotope labeling box.

[0058] Example 3: Different from Example 1;

[0059] Referring to the attached Figures 6-9 , an air circulation device, the air circulation assembly is installed at a position diagonal to the isotope generating device on the cubic support 1. Through the internally connected cubic support 1, the labeled gas can be quickly mixed in the isotope labeling box. The air circulation device includes an air box 15. A C-shaped clamping ring 14 is fixedly connected to one side of the air box 15. The C-shaped clamping ring 14 is clamped on the pipe wall of the vertical pipe 10 and is provided with an opening 35 matching the air inlet 36. A partition is fixedly connected in the air box 15. The partition divides the air box 15 into a drying chamber and an air inlet chamber. A first fan 34 is fixedly connected to one side of the air box 15. The air outlet end of the first fan 34 faces the air inlet 36 and the opening 35;

[0060] The upper end of the bellows 15 is provided with a medicine placement opening, a sealing cover 37 is installed at the medicine placement opening, a second fan 12 is installed at the upper end of the sealing cover 37, the side wall of the bellows 15 is provided with a plurality of air inlets, mesh plates are fixedly connected in the plurality of air inlets, two temperature and humidity sensors 33 are installed at the air inlets, two positioning rings 13 are fixedly connected to the pipe wall of the vertical pipe 10, and positioning protrusions are correspondingly arranged on the positioning rings 13 and are matched with the opening 35 area of the C-shaped clamping ring 14.

[0061] The present invention is provided with an air circulation device. The first fan 34 can be used to extract the gas in the isotope labeling box through the opening 35 and the air inlet and enter into the interior of the cubic support 1. As the first fan 34 continuously promotes the gas flow, the gas in the cubic support 1 is discharged from the exhaust hole 11 at this time. Since the cubic support 1 is provided with 4 vertical pipes 10, it can flow back into the isotope labeling box from four directions and blow near the measured plants, which can quickly circulate and mix the gas in the isotope labeling box, improve the labeling quality. In addition, since the isotope labeling box is in a sealed state, the internal temperature will be higher than the external temperature. At this time, the high temperature will accelerate the evaporation of the soil moisture inside it, resulting in an increase in humidity. Therefore, a desiccant, such as silica gel desiccant, can be placed in the drying chamber. The second fan 12 extracts the gas in the drying chamber and discharges it. The wet air in the isotope labeling box passes through the mesh plate and enters the drying chamber. In this way, a drying cycle can be formed by the second fan 12 to avoid the influence of 13 the high humidity on the stability of CO2 gas. At the same time, the temperature and humidity sensor 33 can be used to detect the temperature and humidity in the isotope labeling box, and the intelligent controller controls the start-stop circuit of the second fan 12. This technology has been widely used in life, and those skilled in the art already know it, so no more details will be given. In addition, the first fan, the second fan and the temperature and humidity sensor are all powered by a mobile power supply.

[0062] The present invention also provides a method for 13 field 13C isotope labeling. This method is applicable to in-situ 13C isotope labeling experiments in ecosystems such as grasslands, small trees, small shrubs, and wetlands. The specific steps are as follows; 13 C isotope in-situ labeling experiment, the specific steps are as follows;

[0063] Step 1: Manufacture the internal cubic support 1. Screw a plurality of horizontal pipes 9 onto the threaded pipes 38 on the plurality of vertical pipes 10 to form the cubic support 1, and install the isotope generating device and the air circulation device diagonally.

[0064] Step 2: In the plot to be marked, select an area of about one square meter. Place the cubic support 1 above the marked plant. Insert the vertical tube 10 of the cubic support 1 into the soil using the drawstring 6 until the bottom edge is flush with the ground to complete the fixation of the cubic support 1. Clear a buffer zone of about 10 cm along the outer periphery of the bottom edge to facilitate subsequent sealing with the plastic film 8. Before that, in the corner of the space covered by the cubic support, clear a bare soil area of 10 cm 2 in size and place an open vial containing 10 ml of 1 mol L –1 sodium hydroxide (NaOH) solution. Cover the vial with an aluminum can with a diameter of 8 cm and a height of 10 cm, and press it firmly to the ground for absorbing soil respiration CO2;

[0065] Step 3: Cover the cubic support 1 with a transparent plastic film 8. Smooth and press the transparent plastic film along the top surface and vertical sides of the cubic support 1 from top to bottom with the inner crimping frame 5. When the environmental temperature is relatively high, cover the plastic film 8 in double layers. The innermost layer is first fixed by the inner crimping frame 5, and then the outermost layer of the plastic film 8 is covered and the double-layer plastic film 8 is fixed using the outer crimping frame 4. At this time, a three-dimensional cavity 40 is formed between the inner and outer plastic films 8. Fix an air pipe joint on the outermost layer of the plastic film 8 to connect to an air pump, and open an exhaust port with the same diameter as the air pipe joint on the corresponding side. Use the air pump to convey gas to make the gas in the cavity 40 flow, so as to achieve the effect of reducing the temperature inside the isotope labeling box;

[0066] Step 4: Slip on the outer crimping frame 4 and fix the four corners of the outer crimping frame 4 to the ground with wedges 7, and then firmly fix the extended transparent plastic film 8 to the ground to complete the assembly of the isotope labeling box;

[0067] Step 5: Use a syringe needle to quantitatively inject 5 ml of concentrated sulfuric acid into the medicine storage tube 26 in the isotope generating device. The concentrated sulfuric acid reacts with Na2 13 CO3 in the medicine storage tube 26 to generate 13 CO2 gas for labeling. Repeat this step 3 times at 1 hour, 2 hours, and 4 hours after the first labeling is completed to complete the labeling process;

[0068] Step 6: 6 hours after the first labeling is completed, insert a syringe into the transparent plastic film, take 100 ml of gas and put it into an air bag for preservation and subsequent index determination. Remove the labeling equipment, and then collect plant, soil, and alkali solution NaOH solution samples.

[0069] Compared with the prior art, in the design process of this technical solution, a flexible detachable cube bracket 1 is made of common durable pipes, and assembled with an economical, practical and recyclable plastic film 8 into an isotope labeling box. The production of this labeling box does not use a large number of heavy main materials, so it is relatively light in weight and convenient to move.

[0070] Using rigid pipes and plastic films, compared with traditional materials such as acrylic sheets, the products made are strong and durable, and there is no problem of being easily damaged during movement, which is suitable for the transportation and movement requirements in scenarios such as changing sample plots in the wild.

[0071] It is equipped with an edge-sealing pressing frame made by the steel bar welding process, which is strong and durable and can be reused repeatedly, effectively ensuring the sealing between the plastic film and the ground.

[0072] The size of the labeling frame can be flexibly adjusted according to the applicable wild scenarios, and it is suitable for in-situ labeling experiments in various wild ecosystems. Since isotope labeling needs to be carried out as simultaneously as possible and with unified operation, it is recommended to prepare a sufficient number of frames and sufficient materials and drugs in advance, and then carry out unified 13 C isotope labeling.

[0073] It should be noted that the term "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0074] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. One for outdoor use 13 A convenient device for C isotope labeling, characterized in that: include: A cubic support (1), the cubic support (1) being assembled from a plurality of transverse tubes (9) and a plurality of vertical tubes (10), the cubic support (1) being covered with a plastic film (8), the cubic support (1) and the plastic film (8) being assembled into an isotope labeling box, the interior of the cubic support (1) being connected and an air inlet (36) being opened on the wall of one of the vertical tubes (10); A side pressing assembly, the side pressing assembly comprising an internal side pressing frame (5) and an external side pressing frame (4), the external side pressing frame (4) adopts a splicing design, and the internal side pressing frame (5) is sleeved on the cubic bracket (1); An isotope generator, which is installed on the vertical side of the cubic support (1) to facilitate the addition of chemicals and can maintain the sealing of the interior of the isotope labeling box when the chemicals are injected; An air circulation device, wherein the air circulation component is installed on a cubic support (1) at a position diagonally opposite to the isotope generating device, and the marking gas can be quickly mixed in the isotope marking box through the internally connected cubic support (1).

2. A method for use in the field according to claim 1 13 A convenient device for C isotope labeling, characterized by: A hemispherical sealing cover is provided at the upper end of the vertical tube (10), and a conical opening (6) is provided at the lower end of the vertical tube (10). Four threaded tubes (38) are fixed on the tube wall of the vertical tube (10). The four threaded tubes (38) are grouped in pairs, and the center lines of the two threaded tubes (38) in each group are perpendicular to each other. One group of the threaded tubes (38) is vertically fixed to the sealing cover above the vertical tube (10), and the other group of the threaded tubes (38) is vertically fixed to the tube wall of the vertical tube (10) above the opening (6). Nuts (39) are fixedly connected to the inner edges of the two tube openings of the transverse tube (9), and the nuts (39) match the tube walls of the threaded tubes (38).

3. A method for use in the field according to claim 1. 13 A convenient device for C isotope labeling, characterized by: A plurality of exhaust holes (11) are provided on the tube walls of the plurality of vertical tubes (10), and the plurality of exhaust holes (11) are all oriented toward the vertical centerline of the cubic support (1). The air inlet (36) provided on the tube walls of the vertical tubes (10) is used for the airflow transported by the air circulation device to enter and be discharged from the plurality of exhaust holes (11).

4. A method for use in the field according to claim 1. 13 A convenient device for C isotope labeling, characterized by: The internal edge pressing frame (5) of the edge pressing assembly is welded with steel bars, and the side length is two centimeters longer than the side length of the cube bracket (1). The external edge pressing frame (4) is spliced ​​with two identical C-shaped bars, and the lower end of the C-shaped bar is fixedly connected with a pressure plate (44) of the same structure, one of the pressure plates (44) of the C-shaped bar is fixedly connected with two fixing seats (42), and the other pressure plate (44) of the C-shaped bar is fixedly connected with two matching insertion strips (41), and the fixing seat (42) is connected with a hand-tightening bolt (43). The four corners of the external edge pressing frame (4) are provided with nail holes, and wedges (7) are inserted into the nail holes.

5. A method for use in the field according to claim 1 13 A convenient device for C isotope labeling, characterized by: The isotope generating device comprises a fixing frame (2), one side of the fixing frame (2) is fixed on the wall of one of the vertical tubes (10), one side of the fixing frame (2) is fixedly connected to a rectangular sleeve (17), a rectangular sleeve (18) is sleeved in the rectangular sleeve (17), one side of the rectangular sleeve (18) is fixedly connected to a sealing plate (3), a rubber seat (25) is fixedly connected in the rectangular sleeve (18), a medicine storage tube (26) is arranged in the rubber seat (25), and the upper end of the rectangular sleeve (18) is provided with a A round mouth is provided in the round mouth, a rubber stopper (28) is provided in the round mouth, the lower end of the rubber stopper (28) extends into the upper end of the medicine storage tube (26) and is fixedly connected to a flow guide tube (27), the flow guide tube (27) is composed of an upper cone (29) and a lower cone (30), a limiting flow hole (32) is provided at the connection between the upper cone (29) and the lower cone (30), a cone bottom is provided at the lower end of the lower cone (30), a plurality of liquid outlet holes (31) are obliquely opened at the cone bottom, and an air outlet is provided on one side of the medicine storage tube (26).

6. A method for use in the field according to claim 5. 13 A convenient device for C isotope labeling, characterized by: A rubber ring is fixedly connected inside the gas outlet, a right-angle elbow (24) is sleeved inside the rubber ring, a clamping seat (23) is provided on one side of the rubber seat (25), a gas cylinder (22) is clamped inside the clamping seat (23), the upper end of the gas cylinder (22) is sealedly connected to a bottle cap (20), one end of the right-angle elbow (24) passes through the bottle cap (20) and extends into the gas cylinder (22), and an air outlet pipe (21) is installed on the other side of the bottle cap (20).

7. A method for use in the field according to claim 5. 13 A convenient device for C isotope labeling, characterized by: A magnetic sealing ring (16) that can be attracted to the fixed frame (2) is fixedly connected to one side of the sealing plate (3); a rubber ring (19) is embedded in the inner edge of the pipe opening at one end of the rectangular sleeve (17); the rubber ring (19) is a hollow structure and is sleeved with the side wall of the rectangular sleeve (18); and a rectangular groove is provided on one side of the fixed frame (2).

8. A method for use in the field according to claim 1. 13 A convenient device for C isotope labeling, characterized by: The air circulation device comprises a wind box (15), one side of the wind box (15) is fixedly connected to a C-shaped clamp ring (14), the C-shaped clamp ring (14) is clamped on the tube wall of the vertical tube (10) and is provided with an opening (35) that matches the air inlet (36), a partition is fixedly connected inside the wind box (15), the partition divides the wind box (15) into a drying chamber and an air inlet chamber, and one side of the wind box (15) is fixedly connected to a first fan (34), the air outlet end of the first fan (34) faces the air inlet (36) and the opening (35); The upper end of the bellows (15) is provided with a medicine placement opening, a sealing cover (37) is installed at the medicine placement opening, a second fan (12) is installed at the upper end of the sealing cover (37), a plurality of air inlets are provided on the side wall of the bellows (15), mesh plates are fixedly connected to the plurality of air inlets, two temperature and humidity sensors (33) are installed at the air inlets, two positioning rings (13) are fixedly connected to the tube wall of the vertical tube (10), and the positioning rings (13) are respectively provided with positioning protrusions that match the opening (35) area of ​​the C-shaped clamping ring (14).

9. A method of using the convenient device described in any one of claims 1 to 8 for outdoor 13 C isotope labeling method is applicable to field research in grassland, small trees, small shrubs, and wetland ecosystems. 13 C isotope in situ labeling experiment, characterized in that The specific steps are as follows; Step 1: Make an internal cubic support (1), screw multiple horizontal tubes (9) onto the threaded tubes (38) on multiple vertical tubes (10) to form a cubic support (1), and install an isotope generator and an air circulation device at opposite corners; Step 2: In the sample plot to be marked, select an area of ​​about one square meter, buckle the cube bracket (1) above the marked plant, insert the vertical tube (10) of the cube bracket (1) into the soil using the tie mouth (6) until the bottom edge is flush with the ground, and complete the fixing of the cube bracket (1). Clean a buffer zone of about 10 cm along the periphery of the bottom edge to facilitate subsequent sealing with a plastic film (8); Step 3: Cover the cube support (1) with a transparent plastic film (8), and use the internal edge pressing frame (5) to smooth and compact the transparent plastic film along the top surface and vertical edges of the cube support (1) from top to bottom; Step 4: insert the external edge pressing frame (4), fix the four corners of the external edge pressing frame (4) to the ground with wedges (7), and then firmly fix the extended transparent plastic film (8) to the ground, thus completing the assembly of the isotope labeling box; Step 5: Use a syringe needle to quantitatively inject 5 ml of concentrated sulfuric acid into the drug storage tube (26) in the isotope generator. The concentrated sulfuric acid and the Na2 13 CO3 reacts to produce 13 CO2 gas was used for labeling. After 1, 2, and 4 hours after the first labeling, this step was repeated 3 times to complete the labeling process. Step 6: 6 hours after the first marking, pierce the transparent plastic film with a syringe, take 100 ml of gas and put it into an air bag for storage and subsequent indicator determination, remove the marking equipment, and then collect plant, soil, and alkali solution (NaOH solution) samples.

10. A method for field 13C isotope labeling according to claim 9, characterized in that: In the step three, when the ambient temperature is high, the plastic film (8) is covered with a double layer, the innermost layer is first fixed by the internal pressing frame (5), and then the outermost layer of the plastic film (8) is covered and the double-layer plastic film (8) is fixed by the external pressing frame (4). At this time, a three-dimensional cavity (40) is formed between the inner and outer plastic films (8), and an air pipe joint is fixed on the outermost layer of the plastic film (8) to connect to an air pump, and an exhaust port with the same diameter as the air pipe joint is opened on the corresponding side. The air pump is used to transport gas to make the gas in the cavity (40) circulate, so as to achieve the effect of reducing the internal temperature of the isotope labeling box.

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