Method and apparatus for liquid safety-detection by backscatter with a radiation source

• US 7,400,706 B2
• Filed: 11/23/2005
• Issued: 07/15/2008
• Est. Priority Date: 11/26/2004
• Status: Active Grant

• Current Assignee: Nuctech Company Limited (Tsinghua Tongfang Co., Ltd.), Tsinghua University
• Original Assignee: Nuctech Company Limited (Tsinghua Tongfang Co., Ltd.), Tsinghua University
• Inventors: Qi, Mingrui, He, Wenjun, Liu, Yinong, Li, Yuanjing, Zhang, Li, Wang, Yi, Chen, Zhiqiang, Hu, Haifeng, Kang, Kejun, Wu, Wanlong, Li, Yulan
• Primary Examiner(s): Ho; Allen C.
• Application Number:
  US11/285,395
• Publication Number:
  US 20060133566A1
• Time in Patent Office: 965 Days
• Field of Search: 378/57, 378/70, 378/76, 378/79, 378/86, 378/87, 378/88, 378/89, 378/90
• US Class Current: 378/89
• CPC Class Codes: G01N 2223/637 liquid
• CPC Class Codes: G01N 23/20066 Measuring inelastic scatter of gamma rays, e.g. Compton effect
• CPC Class Codes: G01N 23/203 Measuring back scattering
• CPC Class Codes: G01V 5/222 measuring scattered radiation

Abstract

A method and an apparatus for liquid safety-detection by backscattering with a radiation source are provided that relate to a radiation detecting technology field. The invention comprises using a radiation source, a collimator, a detector, a data collector and a computer data processor, and has the main steps of: 1) placing a liquid article to be detected onto a rotatable platform; 2) emitting a ray from the radiation source, said ray causing Compton scattering at the surface of the liquid after passing through the package layer of the liquid article; 3) the scattering photons being received by the detector after passing the collimator; 4) the detector transmitting the received data to the data collector; and 5) the data collector transmitting the amplified and shaped data to the computer data processor, which processes the data to obtain the liquid density of the detected article, then compares the result with the densities of dangerous articles in a current database, and gives a warning if the density of the detected article is consistent with that of a dangerous article. Compared to the prior art, the invention is convenient to use, detects rapidly and accurately, has a strong anti-interference, is very safe and reliable to use, and protection is easy.

Claims

1. A method for detecting the safety of a liquid in a packaged liquid article by backscattering with a radiation source, said method comprising:

1) placing said packaged liquid article onto a rotatable platform;

2) emitting a beam of radiation from a radiation source, said beam of radiation causing Compton scattering at the surface of said liquid in said liquid article after passing through said liquid article'"'"'s package;

3) receiving scattered photons from said Compton scattering by a detector after passing said photons through a collimator;

4) transmitting said detector'"'"'s data that is to be output to a data collector, by said detector; and

5) transmitting, by said data collector, data that has been amplified and shaped by said data collector to a computer data processor, and

6) processing said amplified and shaped data to obtain a density for said liquid, then

7) comparing said density of said liquid with the densities of dangerous articles in a database, and

8) giving a warning if the density of said liquid in said liquid article is found to be consistent with that of a dangerous article in said database, by said processor.

2. The method according to claim 1, wherein said radiation source employs an X-ray machine or an isotope as the source of said radiation.

3. The method according to claim 1 or claim 2, wherein said detector employs a solid detector array having scintillation crystal coupling photodiodes.

10. The method according to any one of claim 1 or claim 7, wherein said packaged liquid article on said platform is rotated.

4. An apparatus for detecting the safety of a liquid in a packaged liquid article by backscattering with a radiation source, said apparatus comprising a radiation source (1) for emitting a ray of radiation that causes Compton scattering at the liquid surface of said liquid article after passing through said liquid article'"'"'s package, a collimator (2), a detector (3), a data collector (4) having an amplifying and shaping circuit and a computer data processor (5) having a database of substance densities of dangerous liquids, said apparatus being characterized by that said apparatus further comprises a rotary platform (6) on which said packaged liquid article is placed and that said radiation source (1) is located on one side of the rotary platform (6), that said detector (3) is located on the same side as the radiation source (1) and faces a Compton scattering beam from the detected liquid article, that the collimator (2) is placed in front of the detector (3), that a data output of the detector (3) is connected to the data collector (4), and that the data collector (4) is connected to the computer data processor (5).

5. The apparatus according to claim 4, characterized by that said radiation source (1) employs an X-ray machine or an isotope as the source of said radiation.

6. The apparatus according to claim 4 or 5, characterized by that said detector (3) employs a solid detector array (7) having scintillation crystal coupling photodiodes.

7. A method for detecting the safety of a liquid in a packaged liquid article by backscattering with a radiation source, said method comprisingplacing said article in an apparatus that comprises:

a radiation source (1), that emits a beam of radiation that causes Compton scattering at a surface layer of liquid after passing through a package layer of a liquid article, a collimator (2), a detector (3), a data collector (4) having an amplifying and shaping circuit and a computer data processor (5) having a database of substance densities of known dangerous liquids, characterized by that said apparatus further comprises a rotary platform (6) on which said packaged liquid article to be detected can be placed and that said radiation source (1) is located on one side of said rotary platform (6), that said detector (3) is located on same side as the radiation source (1) and faces a Compton scattering beam of said packaged liquid article, that the collimator (2) is placed in front of the detector (3), that said detector'"'"'s (3) data output is connected to the data collector (4), and that the data collector (4) is connected to the computer data processor (5)

2) emitting a beam of radiation from said radiation source, said beam of radiation causing Compton scattering at the surface of said liquid in said liquid article after passing through said liquid article'"'"'s package;

3) receiving scattered photons from said Compton scattering by a detector after passing said photons through said collimator;

4) transmitting said detector'"'"'s data that is to be output to said data collector, by said detector; and

5) transmitting, by said data collector, data that has been amplified and shaped by said data collector to said computer data processor,

6) processing said amplified and shaped data to obtain a density for said liquid, then

7) comparing said density of said liquid with the densities of said known dangerous liquids in said database, and

8) giving a warning by said processor if the density of said liquid in said liquid article is found to be consistent with that of a known dangerous liquid in said database.

8. The method according to claim 7, characterized by that said radiation source (1) employs an X-ray machine or an isotope as the source of said radiation.

9. The method according to claim 7 or claim 8, characterized by that said detector (3) employs a solid detector array (7) having scintillation crystal coupling photodiodes.