Inflation and exhaust device for measuring activity of nitrogenase

Abstract

The utility model discloses an air charging and exhausting device for measuring the activity of nitrogenase, which comprises a bottle body, a rubber plug is arranged at the upper end of the bottle body, a hose a and a hose b are arranged on the rubber plug, the upper end of the hose a is communicated with a two-way valve a, the upper end of the hose b is communicated with a two-way valve b, and the lower ends of the hose a and the hose b are positioned in the bottle body. The utility model has the beneficial effects that the air tightness of the bottle body is ensured by arranging the rubber plug at the upper end of the bottle body, and the air inflation or air exhaust operation is carried out by controlling the opening and closing of the corresponding ports of the two-way valve a and the two-way valve b, so that the rubber plug is prevented from being manually pulled and installed for many times, the air leakage is avoided, and the accuracy of an experimental result is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of inspection and detection, in particular to an air filling and exhausting device for measuring nitrogenase activity. Background Art

[0002] Nitrogen fertilizer production costs are high, the process is complex, and the utilization rate of farmland is mostly less than 40%. Biological nitrogen fixation is still the main source of nitrogen supply in agricultural ecosystems. It is estimated that about 85% of the world's annual nitrogen fixation comes from biological nitrogen fixation. In order to improve the soil nitrogen supply capacity of agricultural ecosystems and alleviate the environmental pollution caused by excessive nitrogen fertilizer input, making full use of biological nitrogen fixation is an economical and effective method. Biological nitrogen fixation refers to the process in which nitrogen-fixing microorganisms reduce atmospheric nitrogen (N2) to ammonia with the help of nitrogenase catalysis. Therefore, the nitrogenase activity of nitrogen-fixing microorganisms is one of the important indicators reflecting their nitrogen fixation efficiency.

[0003] At present, the acetylene reduction method is often used to determine the activity of nitrogenase. The nitrogenase secreted by nitrogen-fixing microorganisms can not only catalyze the reduction of N2 to ammonia, but also catalyze the reduction of acetylene (C2H2) to ethylene (C2H4). C2H2 and N2 have similar affinities for nitrogenase, and their reduction processes are parallel and related. Therefore, C2H2 can be used as a substitute substrate for N2 to detect the activity of nitrogenase. The specific process is as follows: put the sample containing nitrogen-fixing microorganisms in a 100 ml glass bottle and seal it with an isobutyl rubber stopper. Add 10 ml of C2H2 gas (10%) with a syringe, incubate at a constant temperature, and use a gas chromatograph to detect the concentration of C2H4 in the sample within a certain period of time. Since the peak height of C2H4 is proportional to the content of C2H4 in the gas, the amount of C2H4 in the sample can be determined by the external standard method, thereby estimating the activity level of nitrogenase reduction reaction. However, this method involves multiple inflation and degassing steps, requiring the cooperation of multiple people, resulting in a waste of manpower. At the same time, the traditional glass bottle and rubber stopper combination is prone to leakage, resulting in large errors in the experimental results. Utility Model Content

[0004] The utility model aims to overcome the shortcomings of the prior art and provide a gas filling and exhausting device for measuring nitrogenase activity.

[0005] The purpose of the utility model is achieved through the following technical scheme: a gas filling and exhausting device for determining the activity of nitrogenase, comprising a bottle body, a rubber plug is arranged at the upper end of the bottle body, a hose a and a hose b are arranged on the rubber plug, the upper end of the hose a is connected to the two-way valve a, the upper end of the hose b is connected to the two-way valve b, and the lower ends of the hose a and the hose b are both located in the bottle body.

[0006] Preferably, the height of the lower end of hose a is higher than the height of the lower end of hose b.

[0007] Preferably, a step is provided on the rubber plug, and the opening end of the bottle body is located on the step.

[0008] Preferably, the diameter of the upper surface of the rubber plug is larger than the opening diameter of the bottle body.

[0009] Preferably, the two-way valve a and the two-way valve b are both made of PVC.

[0010] Preferably, hose a and hose b are silicone peristaltic pump tubes.

[0011] The utility model has the following advantages: the utility model ensures the air tightness of the bottle body by arranging a rubber plug at the upper end of the bottle body, and performs inflation or exhaust operation by controlling the opening and closing of the corresponding ports of the two-way valve a and the two-way valve b, thereby avoiding manual multiple extraction and installation of the rubber plug, avoiding air leakage, and ensuring the accuracy of the experimental results. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the gas filling and exhausting device;

[0013] In the figure, 1-bottle body, 2-rubber plug, 3-two-way valve a, 4-two-way valve b, 6-switch a, 7-switch b, 11-hose a, 12-hose b. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0015] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0016] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0017] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0018] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the utility model product is usually placed when in use, or the positions or positional relationships commonly understood by those skilled in the art, which are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0019] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] In this embodiment, if Figure 1 As shown, a gas filling and pumping device for determining nitrogenase activity includes a bottle body 1, a rubber plug 2 is provided at the upper end of the bottle body 1, a hose a11 and a hose b12 are provided on the rubber plug 2, the upper end of the hose a11 is connected to the two-way valve a3, the upper end of the hose b12 is connected to the two-way valve b4, and the lower ends of the hose a11 and the hose b12 are both located in the bottle body 1, preferably, the hose a11 and the hose b12 are silicone peristaltic pump tubes. By providing the rubber plug 2 at the upper end of the bottle body 1, the air tightness of the bottle body 1 is ensured, and then the corresponding ports of the two-way valve a3 and the two-way valve b4 are controlled to open and close to perform inflation or pumping operations, avoid multiple manual extraction and installation of the rubber plug 2, avoid air leakage, and ensure the accuracy of the experimental results. In this embodiment, the bottle body 1 is made of high borosilicate glass.

[0021] Furthermore, the lower end height of the hose a11 is higher than the lower end height of the hose b12. Specifically, the outlet pipe of the nitrogen bottle is first connected to the two-way valve b4. After the nitrogen filling begins, the experimenter opens the two-way valve b4 and the two-way valve a3 in turn by turning the switch b7 and the switch a6, and flushes the bottle body 1 with a nitrogen flow rate of 10 ml / s for 15 seconds; the nitrogen enters the bottle body 1 through the III end and the IV end in turn. Since the lower end height of the hose a11 is higher than the lower end height of the hose b12, when the nitrogen goes out through the II end and the I end in turn, it means that the bottle is full of nitrogen, the nitrogen input is stopped, and then the two-way valve a3 and the two-way valve b4 are closed in turn to complete the nitrogen filling operation.

[0022] In this embodiment, a step is provided on the rubber plug 2, and the opening end of the bottle body 1 is located on the step. Furthermore, the diameter of the upper surface of the rubber plug 2 is larger than the opening diameter of the bottle body 1. Specifically, the diameter of the lower surface of the rubber plug 2 is slightly larger than the opening diameter of the bottle body 1, so that the friction force can be increased and the sealing performance can be ensured. The main function of the upper surface diameter of the rubber plug 2 being larger than the opening diameter of the bottle body 1 is to facilitate the experimenter to remove the rubber plug 2.

[0023] In this embodiment, the two-way valve a3 and the two-way valve b4 are both made of PVC.

[0024] In another embodiment, a thread is provided on the outer side of the opening of the bottle body 1, on which an outer cover is installed, and a through hole is opened in the middle of the outer cover. When the outer cover is installed, the plug 2 is installed on the inner side of the opening of the bottle body 1, that is, the plug 2 is located below the through hole.

[0025] The working process of the utility model is as follows: first, the nitrogen bottle outlet pipe is connected to the two-way valve b4. After the nitrogen filling starts, the experimenter opens the two-way valve b4 and the two-way valve a3 in turn by turning the switch b7 and the switch a6, and flushes the bottle body 1 with a nitrogen flow rate of 10 ml / s for 15 seconds; the nitrogen enters the bottle body 1 through the III end and the IV end in turn. Since the lower end height of the hose a11 is higher than the lower end height of the hose b12, when the nitrogen goes out through the II end and the I end in turn, it means that the bottle is full of nitrogen, the nitrogen input is stopped, and then the two-way valve a3 and the two-way valve b4 are closed in turn to complete the nitrogen filling operation;

[0026] After the nitrogen filling is completed, an empty syringe is connected to the I end of the two-way valve a3, and the experimenter turns the switch a6 to open the two-way valve a3, draws 10 ml of nitrogen through the syringe, and immediately turns the switch a6 to close the two-way valve a3, and then connects the syringe filled with 10 ml of acetylene to the III end of the two-way valve b4. The experimenter turns the switch b7 to open the two-way valve b4, fills the bottle 1 with 10 ml of acetylene gas, and immediately turns the switch b7 to close the two-way valve b4 to keep the bottle 1 sealed, completing the acetylene filling operation;

[0027] After the acetylene filling operation is completed, the bottle 1 is placed in a constant temperature culture at 28°C for 48 h. After the culture is completed, the bottle 1 is shaken to mix the internal gas evenly, and then an empty syringe is connected to the I end of the two-way valve a3. The experimenter turns the switch a6 to open the two-way valve a3, draws 10 ml of the gas to be tested through the syringe, and immediately turns the switch a6 to close the two-way valve a3 to complete the gas extraction operation;

[0028] After the gas extraction operation is completed, the ethylene peak value is measured by a gas chromatograph, and the ethylene concentration and the nitrogenase activity are calculated according to the standard gas peak value, thereby avoiding the manual extraction and installation of the rubber plug 2 for many times, avoiding air leakage, and ensuring the accuracy of the experimental results. In this embodiment, the calculation of the ethylene concentration and the nitrogenase activity are both calculated using the existing method, which is not improved here and will not be described in detail.

[0029] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A gas filling and exhausting device for measuring nitrogenase activity, characterized in that: The invention comprises a bottle body (1), wherein a rubber plug (2) is arranged at the upper end of the bottle body (1), and a hose a (11) and a hose b (12) are arranged on the rubber plug (2), wherein the upper end of the hose a (11) is connected to a two-way valve a (3), and the upper end of the hose b (12) is connected to a two-way valve b (4), and the lower ends of the hose a (11) and the hose b (12) are both located inside the bottle body (1).

2. The gas filling and exhausting device for measuring nitrogenase activity according to claim 1, characterized in that: The height of the lower end of the hose a (11) is higher than the height of the lower end of the hose b (12).

3. The gas filling and exhausting device for measuring nitrogenase activity according to claim 2, characterized in that: The rubber stopper (2) is provided with a step, and the opening end of the bottle body (1) is located on the step.

4. The gas filling and exhausting device for measuring nitrogenase activity according to claim 3, characterized in that: The diameter of the upper surface of the rubber plug (2) is greater than the opening diameter of the bottle body (1).

5. The gas filling and exhausting device for measuring nitrogenase activity according to claim 4, characterized in that: The two-way valve a (3) and the two-way valve b (4) are both made of PVC.

6. The gas filling and exhausting device for measuring nitrogenase activity according to claim 5, characterized in that: The hose a (11) and the hose b (12) are silicone peristaltic pump tubes.

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