Radioactivity detection device

Abstract

The utility model relates to a radioactivity detection device which is mainly composed of a measuring tube, a sample pressing plate and a radioactivity detector. The radioactivity detector is composed of a protective film, a scintillator, a light guide, a photomultiplier and a measuring circuit. The radioactivity detector is installed in the measuring tube, a sample is directly placed in the measuring tube after being smashed, and the sample pressing plate is used for pressing the sample and covering the radioactivity detector, so that the radioactivity of the sample is directly measured. Sample preparation and measurement are combined, sample preparation is more convenient and accurate, samples are directly attached to the radioactivity detector, and the efficiency is higher compared with measurement through a sample box.

Description

Technical Field

[0001] The utility model relates to the field of food detection, in particular to a radioactive detection device used for radioactive detection of food. Background Art

[0002] For aquatic products contaminated by nuclear contaminated water, the main measured radionuclides are cesium-137 and strontium-90. The existing food radioactivity detection is measured by sodium iodide gamma spectrometer and high-purity germanium gamma spectrometer. The sample needs to be crushed and stirred and placed in a sample box of a specific shape and size, and then the sample box is placed in the instrument for measurement, or the sampling laboratory low-background αβ detector is used for measurement, and the sample needs to be ashed. All of the above instruments are laboratory measuring instruments, and sampling and sample preparation are cumbersome, and the measurement cycle is long. They cannot adapt to the high-frequency radioactivity measurement of a large number of imported aquatic products. In view of the large volume of radioactivity detection of imported aquatic products at ports and the requirements for customs clearance speed, a radiation detection device with simple structure, convenient and fast operation is needed. Summary of the invention

[0003] The utility model aims to overcome the above shortcomings. It adopts a scintillator detector, which is directly installed in the measuring tube. No sample box is required. The sample is directly introduced into the measuring tube, and the sample pressing plate is pressed down to quickly prepare the sample. The device has a simple structure and is easy to operate. It is suitable for rapid radioactivity measurement of imported aquatic products at ports.

[0004] The utility model is a radioactive detection device, which is mainly composed of a measuring tube, a sample pressing plate and a radioactive detector; the radioactive detector is composed of a protective film, a scintillator, a light guide, a photomultiplier tube and a measuring circuit; the protective film and the light guide are respectively installed on two sides of the scintillator, the protective film is located on one side of the detection surface of the radioactive detector, and faces the sample pressing plate; the photomultiplier tube is installed on the light guide; the radioactive detector is installed in the measuring tube; the sample pressing plate is made of hard material, and the sample pressing plate can move up and down in the measuring tube.

[0005] In the radioactive detection device, the sample pressing plate is provided with air holes. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 It is a three-dimensional diagram of an embodiment of the utility model.

[0007] Figure 2 It is a cross-sectional view of an embodiment of the utility model. DETAILED DESCRIPTION

[0008] The following is an explanation of the implementation method of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0009] See also Figure 1 , Figure 2 It should be noted that the illustrations provided in this embodiment are only used to schematically illustrate the basic concept of the utility model, and the illustrations only show the structures related to the utility model rather than being drawn according to the shapes and sizes in actual implementation. The shape and proportion of the actual implementation may be changed arbitrarily, and the structural layout may also be more complicated.

[0010] The utility model is further described below in conjunction with the accompanying drawings and an implementation example thereof.

[0011] A radioactive detection device of the present embodiment mainly comprises a measuring tube (1), a sample pressing plate (2), and a radioactive detector (3); the radioactive detector (3) comprises a protective film (31), a scintillator (32), a light guide (33), a photomultiplier tube (34), and a measuring circuit; the protective film (31) and the light guide (33) are respectively mounted on both sides of the scintillator (32); the protective film (31) is located on one side of a detection surface (35) of the radioactive detector, facing the sample pressing plate (2); the photomultiplier tube (34) is mounted on the side of the detection surface (35) of the radioactive detector; Installed on the light guide (33); in this embodiment, in order to reduce the absorption of radiation by the protective film, the protective film (31) adopts a low-density and high-strength carbon fiber film; the light guide (33) adopts a high-transmittance optical organic glass. In order to better guide light, the light guide (33) is designed as a conical structure, and the side surface is sprayed with high-reflective titanium dioxide; the scintillator (32) can adopt a sodium iodide scintillator and a thin plastic scintillator, which are used to measure gamma rays and beta rays respectively; the contact surface between the scintillator (32) and the protective film (31) is sprayed with high-reflective titanium dioxide. The radioactive detector (3) is installed in the measuring tube (1); the sample pressing plate (2) is made of a hard material, which can be metal or plastic. In this embodiment, it is made of aluminum alloy. The sample pressing plate (2) can move up and down in the measuring tube (1). The sample (4) is placed between the sample pressing plate (2) and the radioactive detector (3), or the sample pressing plate (2) can be fixed to the measuring tube (1) and remain stationary, while the radioactive detector (3) moves up and down. According to this embodiment, the radioactive detector (3) is fixed to the measuring tube (1) and is immovable. The periphery of the radioactive detector (3) is sealed to the measuring tube (1) by a sealing ring or a sealing glue to prevent sample leakage. The sample pressing plate (2) can move up and down in the measuring tube (1). An O-ring sealing ring or a sliding sealing ring is provided on the side of the sample pressing plate (2) to ensure that the sample pressing plate (2) can be sealed even when it moves up and down. In order to change the air between the sample pressing plate (2) and the radioactive detector (3) when the sample pressing plate (2) moves up and down, an air vent (21) is provided in the sample pressing plate (2).

[0012] According to different measurement requirements, the distance between the sample pressing plate (2) and the radioactive detector (3) may be different. In order to more conveniently adjust the distance, based on the present embodiment, the sample pressing plate (2) may be installed on a lifting module, such as a ball screw module, to replace manual operation. By controlling the lifting module to automatically lift and lower, the moving distance of the sample pressing plate (2) may be controlled.

[0013] The working process of the ballast water sampling device of the utility model is as follows: the sample pressing plate (2) is lifted, and then the sample is directly poured into the measuring tube (1); the sample pressing plate (2) is placed into the measuring tube (1) and then pressed down, air is squeezed out from the air vent (21), the sample is pressed into shape, and the radioactivity detector (3) is turned on to start measurement.

[0014] For this embodiment, further, in order to facilitate operation, a sample injection hole can be opened on the sample pressing plate (2), and the sample can be poured into the measuring tube (1) through the sample injection hole without lifting the sample pressing plate (2).

[0015] The utility model is a radioactive detection device that installs a radioactive detector in a measuring tube. The sample to be tested is directly poured into the measuring tube. No additional sample box is required. The sample can be pressed down directly with a sample pressing plate to quickly and accurately press the sample into the required shape and size. The device has a simple structure and is quick and easy to operate. It avoids the cumbersome operation of using a sample box to prepare samples for existing instrument measurements, improves the efficiency of on-site food radioactive detection, and is particularly easy to operate in the radioactive detection of food at entry ports. It can be directly measured on site, saves measurement time, and improves customs clearance efficiency.

[0016] Finally, it should be noted that the above examples are only illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology can modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the relevant technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A radioactive detection device, Features It is mainly composed of a measuring tube, a sample pressing plate, and a radioactive detector; the radioactive detector is composed of a protective film, a scintillator, a light guide, a photomultiplier tube, and a measuring circuit; the protective film and the light guide are respectively installed on both sides of the scintillator, and the protective film is located on the detection side of the radioactive detector, facing the sample pressing plate; the photomultiplier tube is installed on the light guide; the radioactive detector is installed in the measuring tube; the sample pressing plate is made of hard material, and the sample pressing plate can move up and down in the measuring tube.

2. The radioactive detection device according to claim 1, Features The sample pressing plate is provided with air holes.

Images