CN109254318B - 3D printing process on-line real-time monitoring method based on positron annihilation - Google Patents

3D printing process on-line real-time monitoring method based on positron annihilation Download PDF

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CN109254318B
CN109254318B CN201810810598.9A CN201810810598A CN109254318B CN 109254318 B CN109254318 B CN 109254318B CN 201810810598 A CN201810810598 A CN 201810810598A CN 109254318 B CN109254318 B CN 109254318B
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printing
positron
printing process
annular array
array detector
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CN109254318A (en
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肖辉
赵敏
刘兼唐
姚敏
陈皓
梁欢
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Nanjing University of Aeronautics and Astronautics
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Nanjing University of Aeronautics and Astronautics
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Abstract

The invention discloses a positron annihilation-based 3D printing process online real-time monitoring method, which comprises the following steps of: a. selecting the species of positive electron nuclides to generate positive electron nuclides with activity; b. enabling the interior of the 3D printing object to uniformly and continuously generate positrons by using a positron nuclide; c. fixing a 3D printer inside a gamma photon annular array detector for collecting gamma photon data generated by positron annihilation in real time; d. and establishing a mathematical model of the corresponding relation between the positron nuclide concentration distribution and the image pixels, and obtaining a 3D image of the distribution condition of the printing material in the printing process of the 3D printer by adopting an MLEM (multi-level emission EM) or OSEM (open source imaging) mathematical algorithm. The invention has the advantages of space synchronous imaging, high imaging efficiency, short testing time, good imaging quality and no radiation hazard; the invention reconstructs a 3D image of the spatial state distribution of the printing material through a mathematical algorithm, and intuitively and vividly achieves the aim of online real-time monitoring of the 3D printing process.

Description

3D printing process on-line real-time monitoring method based on positron annihilation
Technical Field
The invention belongs to the technical field of 3D printing, and particularly relates to a positron annihilation-based 3D printing process online real-time monitoring method.
Background
The field of the relatively mature application of gamma photon three-dimensional imaging based on positron annihilation is the clinical use of PET (positron emission tomography) in the biomedical field. The scholars of the university of Innova Habib Zaidi studied the improvement of the spatial resolution of PET instruments in 2007, think that PET/CT can replace pure PET, and think that PET/MRI has higher imaging precision than PET/CT in 2008. Meanwhile, Martin S Judenhofer at the university of California studies how a PET detector evaluates the performance of a data acquisition board in the high-speed sampling process in 2004, and a paper is published in Nature Medicine in 2008, which proves that PET/MRI is a new method for studying biological functions and morphological imaging, and scholars engaged in positron annihilation 3-dimensional imaging research worldwide shift the research focus to the theoretical research of PET/CT and PET/MRI since 2007. The PET/CT and PET/MRI devices have higher imaging precision in the aspect of biomedical 3-dimensional imaging.
A gamma photon 3-dimensional imaging detection technology based on positron annihilation is premised on a proper positron generation mode, the currently common positron generation mode is a cyclotron positron generation method, an ion source at the central part of a cyclotron emits a particle beam through high-voltage arc discharge to gas ionization, the particle beam moves in a semicircular electrode box, a high-frequency oscillation power supply connected with the electrode box provides an alternating electric field for the particles, under the action of a magnetic field and an electric field, the accelerated particles move and fly in a track similar to a spiral track and enter another electrode box, the track radius of the another electrode box is larger than that of the previous electrode box, after the charged particles are accelerated for multiple times, the track radius reaches the maximum and the maximum energy is obtained, at the moment, the particles are extracted by a beam extraction device and led into a target chamber to irradiate target nuclei, so that the target nuclei are lack of neutrons to become positive electronic nuclides, the principle is shown in fig. 1. In clinical medicine, after some organic solutions are repeatedly accelerated by a cyclotron, various medical imaging agents with half-lives ranging from several minutes to several hours are generated, such as solutions of fluorodeoxyglucose, fatty acid, protein and the like, and the solutions marked with nuclides can be absorbed by specific organism organs to show disease parts in a three-dimensional image, so that the purpose of disease diagnosis is achieved.
Positrons are extremely unstable in a natural state, and after a picosecond-level thermalization process, positron annihilation events can occur with surrounding electrons, a pair of gamma photons with energy of 511KeV and directions of 180 degrees are generated, the gamma photons form a response line (straight line), and the response line is recorded by a pair of gamma photon detectors, and the principle of the gamma photon detector is shown in FIG. 2.
At present, a gamma photon 3-dimensional imaging detection technology based on positron annihilation is mature in the field of clinical disease diagnosis, but is researched by few scholars in the field of industrial detection, and although a 3D printing technology has a fire explosion market, the 3D printer has various printing modes, the industrial standard is not perfect, and the evaluation of a processing technology does not form a uniform technical standard. The nondestructive testing method for the 3D printed test piece generally adopts X-ray detection, electron microscope monitoring and the like, and the method has the defects of high cost, large radiation hazard, detection of shallow surface defects only, incapability of online real-time monitoring and the like in actual detection. The industrial CT detection process is plane asynchronous imaging, the imaging efficiency is low, the testing time is long, and online real-time detection cannot be realized. The optical microscope and the transmission electron microscope cannot detect the inner cavity of the part; the detection depth of X-ray scattering can reach centimeter level, but the resolution of the defect size does not reach nanometer level.
Disclosure of Invention
The purpose of the invention is as follows: in order to overcome the defects in the prior art, the invention aims to provide a 3D printing process on-line real-time monitoring method based on positron annihilation.
The technical scheme is as follows: the invention discloses a positron annihilation-based 3D printing process online real-time monitoring method, which comprises the following steps of:
a. preparing corresponding positron nuclide according to the time consumed in the 3D printing processing process, the printing material and other parameters, and selecting the type of the positive electron nuclide to generate the positive electron nuclide with activity;
b. according to different printing materials of the 3D printer, positron nuclide is used to enable positron to be generated uniformly and continuously in the 3D printing object in the 3D printing process;
c. fixing a 3D printer inside a gamma photon annular array detector according to the detection precision, the type of a 3D printing material and the size of the 3D printer, and collecting gamma photon data generated by positron annihilation in real time;
d. and establishing a mathematical model of the corresponding relation between the positron nuclide concentration distribution and the image pixels, and obtaining a 3D image of the distribution condition of the printing material in the printing process of the 3D printer by adopting an MLEM (multi-level emission EM) or OSEM (open source imaging) mathematical algorithm.
The positive electron species in step a is 18 F、 127 Xe or 55 Of Fe, positive electron speciesThe activity is 0.1 mCi-1 mCi. The positive electron nuclide is prepared by a cyclotron system, the main basis for selecting the type of the positron nuclide is the time required by the test, and the positive electron nuclide with the half-life period meeting the requirement is selected according to the test time. According to practical experience, the half-life of the positive electron species needs to be more than 5 times of the test time. After the positive electron nuclide species are determined, positron nuclides with proper activity need to be prepared according to the filling rate set during 3D printing, and when the set filling rate is larger, the activity of the prepared positron nuclides is also improved, and vice versa.
When the printing material of the 3D printing object in the step b is resin, marking positive electron nuclides into the 3D printing material; when the printing material of the 3D printing object is metal, the inert gas in the 3D printer is changed into positive electron nuclide. The 3D printing can be classified into PLA printing and metal printing according to the type of printing material, in order to ensure that positive electrons are continuously and uniformly generated inside a 3D printing object in the 3D printing process, the mode of marking the positive electron nuclide on the 3D printing material is as follows, when the PLA is printed, a certain compound is generally extracted from the PLA material, the chain structure of the compound is analyzed, and the terminal of the chain is modified with OTS groups (such as 18 F) Achieving the purpose of labeling positron nuclide, such as labeling positive electron nuclide 18F into a BTE precursor; in metal printing, inert gas inside a 3D printer is generally changed into positron nuclide, such as common xenon for 96 hours, and after the irradiation product is cooled and absorbed into a container at the temperature of liquid nitrogen, the positron nuclide can be generated 127 Xe, then positive electron species 127 Xe is injected into a 3D printer.
In the step c, the diameter of the gamma photon annular array detector is 50 cm-100 cm, and the gamma photon annular array detector is an LYSO annular array detector, a BGO annular array detector or an LSO annular array detector.
Has the advantages that: compared with the prior art, the invention has the following remarkable characteristics: the invention has the advantages of space synchronous imaging, high imaging efficiency, short testing time, good imaging quality and no radiation hazard; according to the invention, positive electron nuclide is marked inside the printing material, so that positive electrons are fully generated from the inside of the printing material in the 3D printing process, and are reconstructed into a 3D image of the printing material in a spatial state distribution through a mathematical algorithm, and the purpose of online real-time monitoring of a 3D printing process is intuitively and vividly achieved; the method intuitively and vividly reflects the filling condition between layers, the bending condition of a 3D printing complex test piece cavity and the connection condition of a seam in the 3D printing process by generating positrons in the printing material and performing real-time 3D imaging, and the detection precision of positrons generated by positron nuclides in positron liquid is high, and the detection size of defects on the inner wall and the surface of the 3D printing test piece can reach the nanometer level; the invention takes gamma photons as a defect information carrier, and is not interfered by external factors such as temperature, pressure intensity, electric field, magnetic field and the like of a test environment; the present invention has no specific requirements for 3D printed materials, which must not be electrically conductive as is required for electromagnetic noise detection methods.
Drawings
Figure 1 is a schematic diagram of cyclotron positron generation.
Fig. 2 is a schematic diagram of positron annihilation to produce gamma photons.
Fig. 3 is a schematic diagram of the evaluation application of a positron annihilation-based gamma photon 3-dimensional imaging detection technology in a 3D printing processing technology.
FIG. 4 is a drawing showing 18 F-labelling to BTE precursor scheme.
Fig. 5 is a schematic diagram of gamma photon image reconstruction.
Fig. 6 is a 3D image of a 3D printed object image and a spatial distribution of printed material.
Fig. 7 is another 3D printed object diagram.
Detailed Description
Example 1
When the printing material is PLA, the method for monitoring the 3D printing process on line in real time based on positron annihilation comprises the following steps:
step one, producing H-containing product by an accelerator 18 H of F 2 18 O solution in N 2 Flow-transported positron nuclides 18 F activity 0.1mCi, passed through a QMA solid phase extraction column (10mL NaHCO at 0.5mol/L concentration) 3 Rinsing and reusing20mL of ultra pure water rinse), H 18 F was adsorbed on QMA solid phase extraction column using 1.5mL K222/K after adsorption 2 CO 3 Eluting the eluate to a reaction tube, heating the mixture to 105 ℃ by a heater, and evaporating the solvent under nitrogen flow;
step two, adding 2mL of anhydrous acetonitrile again, evaporating the solvent to dryness at 105 ℃ under the action of nitrogen flow, starting a cooling fan to cool the reaction tube to below 50 ℃, then adding an acetonitrile solution of a BTE precursor (10mg of the precursor dissolved in 1mL of acetonitrile), heating the reaction solution at 90 ℃ for 10min, cooling to room temperature after the reaction is finished, separating and purifying by using a C-18 column, and finally taking a certain amount of acetonitrile 18 F-BTE is mixed into the 3D printing material and stirred for 10 minutes, and the marking principle is shown in figure 4;
step three, constructing an LYSO annular array detector with the diameter of 50cm, fixing a 3D printer in the LYSO annular array detector, and collecting gamma photon data generated by positron annihilation in real time;
and step four, establishing a mathematical model of the corresponding relation between the positron nuclide concentration distribution and the image pixels, and obtaining a 3D image of the printing material distribution condition in the printing process of the 3D printer by adopting an MLEM mathematical algorithm.
Example 2
When the printing material is metal Fe, the 3D printing process on-line real-time monitoring method based on positron annihilation comprises the following steps:
step one, selecting positron nuclide 127 Xe, generating a positron nuclide with an activity of 1mCi 127 Xe;
Step two, using positron nuclide 127 Xe enables positron to be generated uniformly and continuously in the 3D printing object during the 3D printing process;
thirdly, a BGO annular array detector with the diameter of 100cm is built, and a 3D printer is fixed in the gamma photon annular array detector and is used for collecting gamma photon data generated by positron annihilation in real time;
and step four, establishing a mathematical model of the corresponding relation between the positron nuclide concentration distribution and the image pixels, and obtaining a 3D image of the distribution condition of the printing material in the printing process of the 3D printer by adopting an OSEM mathematical algorithm.
Example 3
When the printing material is polypropylene resin, the 3D printing process on-line real-time monitoring method based on positron annihilation comprises the following steps:
step one, selecting positron nuclide 55 Fe, to form a positron nuclide with an activity of 0.5mCi 55 Fe;
Step two, using positron nuclide 55 Fe enables positive electrons to be uniformly and continuously generated inside the 3D printing object in the 3D printing process;
step three, an LSO annular array detector with the diameter of 75cm is built, and a 3D printer is fixed inside the gamma photon annular array detector and used for collecting gamma photon data generated by positron annihilation in real time and coincident with detection;
and step four, establishing a mathematical model of the corresponding relation between the positron nuclide concentration distribution and the image pixels, and obtaining a 3D image of the distribution condition of the printing material in the printing process of the 3D printer by adopting an MLEM mathematical algorithm.
The method comprises the steps of generating positrons inside a printing material in the 3D printing process, acquiring gamma photon data and reconstructing gamma photon 3-dimensional images, and obtaining 3-dimensional imaging of the printing material in the spatial distribution state of a printing object, realizing online real-time monitoring of the 3D printing process, filling the blank of application of the gamma photon 3-dimensional imaging detection technology in the 3D printing processing process detection field, wherein the principle is as shown in figure 3, a 3D printer 1 is installed in a gamma photon annular array detector 6, the 3D printer 1 comprises a servo system 3, a printing head 4 and a printing platform 5, and the 3D printing material 2 is connected with the 3D printer 1 through a feeding pipe. The gamma photon annular array detector 6 is preferably a LYSO annular array detector, a BGO annular array detector or a LSO annular array detector.
The distribution of the positive electron nuclide in the 3D printing object is reconstructed into a 3D image, so that the purpose of online real-time monitoring of a positron annihilation 3D printing process can be realized, therefore, a corresponding relationship between the positive electron nuclide and an image pixel/voxel needs to be established, as a positron generates a response line (a pair of gamma photons), only the corresponding relationship between the response line recorded by a detector and the image pixel/voxel needs to be established, the principle of the method is shown in fig. 5, the nuclide in the 3D printing object 9 continuously generates positrons, the nuclide with certain activity generates a certain number of positrons, one positron annihilation generates a pair of gamma photons with directions forming 180 degrees, the pair of gamma photons form a response line, namely a gamma photon running track 10, and the response line is recorded by a pair of gamma photon detectors 7, so that the position of the positron annihilation is always on the connection line of the pair of gamma photon detectors 7, the MLEM/OSEM algorithm aims to find the position of the positron annihilation point 8, and the number of the positron annihilation points 8 represents the size of an image pixel.
Applications 1
As shown in FIG. 6, with an activity of 0.5mCi 18 The F nuclide is used for carrying out experiments, and the filling condition between layers, the bending condition of a cavity of a complex test piece and the connection condition of a seam can be clearly detected in the 3D printing process through a positron annihilation 3D imaging detection technology.
Application 2
With activity 1mCi, as in FIG. 7 55 The Fe nuclide is subjected to an experiment, and the leakage region, the leakage position and the inner wall distribution of the 3D printed object, namely the circle part in the figure 7, can be clearly detected by a positron annihilation 3D imaging detection technology.

Claims (3)

1. A3D printing process on-line real-time monitoring method based on positron annihilation is characterized by comprising the following steps:
(a) selecting the species of positive electron nuclides to generate positive electron nuclides with activity;
(b) positron nuclides are used for enabling positrons to be uniformly and continuously generated inside the 3D printing object in the 3D printing process;
(c) fixing a 3D printer inside a gamma photon annular array detector for collecting gamma photon data generated by positron annihilation in real time;
(d) establishing a mathematical model of the corresponding relation between the positron nuclide concentration distribution and the image pixels, and obtaining a 3D image of the distribution condition of the printing material in the printing process of the 3D printer by adopting an MLEM (multi-level emission EM) or OSEM (open source imaging) mathematical algorithm;
the positive electron species in the step (a) is 18 F、 127 Xe or 55 Fe, the activity of the positive electron nuclide is 0.1mCi to 1 mCi;
the diameter of the gamma photon annular array detector in the step (c) is 50 cm-100 cm, and the gamma photon annular array detector is an LYSO annular array detector, a BGO annular array detector or an LSO annular array detector.
2. The positron annihilation-based 3D printing process on-line real-time monitoring method of claim 1, wherein: when the printing material of the 3D printing object in the step (b) is resin, marking positive electron nuclide into the 3D printing material.
3. The method for on-line real-time monitoring of the 3D printing process based on positron annihilation according to claim 1, wherein: and (c) when the printing material of the 3D printing object in the step (b) is metal, changing inert gas in the 3D printer into positive electron nuclide.
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Publication number Priority date Publication date Assignee Title
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1172566A (en) * 1997-08-29 1999-03-16 Toshiba Corp Gamma camera system
CN102109476A (en) * 2009-12-29 2011-06-29 同方威视技术股份有限公司 Method and system for detecting material defects based on photonuclear reaction
CN106108934A (en) * 2016-08-31 2016-11-16 清华大学 Many gammaphotons are launched the medicine time simultaneously and are met nuclear medicine imaging system and method
CN106388845A (en) * 2015-11-19 2017-02-15 南京瑞派宁信息科技有限公司 Positron emission cerenkov-gamma bi-radiation imaging method and device

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7402807B2 (en) * 2005-11-02 2008-07-22 Siemens Medical Solutions Usa, Inc. Method for reducing an electronic time coincidence window in positron emission tomography
PL388555A1 (en) * 2009-07-16 2011-01-17 Uniwersytet Jagielloński Linear device and method for determining the location and time of reaction of gamma quanta and the use of the device for determining the location and time of reaction of gamma quanta in positron emission tomography
CN104865280A (en) * 2015-04-30 2015-08-26 南京航空航天大学 Positron liquid perfusion system and method
CN105158278B (en) * 2015-09-01 2018-01-02 南京航空航天大学 Pass through the nondestructive detection system and detection method of positive electron probe positioning cavity inner wall defect
CN105241909B (en) * 2015-10-08 2018-07-20 南京航空航天大学 From the device and method sought formula positive electron liquid and positioned to inner cavity of component and surface defect
WO2017156113A1 (en) * 2016-03-09 2017-09-14 University Of Maryland, Baltimore Techniques for producing an image of radioactive emissions using a compton camera and compton lines
CN108167271A (en) * 2017-11-22 2018-06-15 南京航空航天大学 Hydraulic oil bubble and the system and method for hydraulic part leakage are detected using positron annihilation technique

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1172566A (en) * 1997-08-29 1999-03-16 Toshiba Corp Gamma camera system
CN102109476A (en) * 2009-12-29 2011-06-29 同方威视技术股份有限公司 Method and system for detecting material defects based on photonuclear reaction
CN106388845A (en) * 2015-11-19 2017-02-15 南京瑞派宁信息科技有限公司 Positron emission cerenkov-gamma bi-radiation imaging method and device
CN106108934A (en) * 2016-08-31 2016-11-16 清华大学 Many gammaphotons are launched the medicine time simultaneously and are met nuclear medicine imaging system and method

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
利用轫致辐射X射线进行正电子分析的研究;张翼等;《核电子学与探测技术》;20110420(第04期);全文 *
符合线路SPECT显像原理及其应用;王荣福;《中国医学装备》;20130115(第01期);全文 *

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