Eureka AIR delivers breakthrough ideas for toughest innovation challenges, trusted by R&D personnel around the world.

Method for reducing breakage rate of quartz tubes during preparation of scintillation single crystals

A preparation process, quartz tube technology, applied in the direction of single crystal growth, single crystal growth, chemical instruments and methods, etc., can solve the large volume change of scintillation crystal material with temperature, low expansion coefficient of scintillation crystal material, and small expansion coefficient of quartz tube and other problems, to achieve the effect of reducing the risk of crystal cracking, reducing the probability of self-absorption, and reducing internal stress

Active Publication Date: 2018-02-09
NORTHEASTERN UNIV
View PDF1 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the expansion coefficient of the quartz tube is small, and the linear expansion coefficient is only 5×10 in the range of 0 to 1000°C. -6 K -1 , its volume changes very little with temperature, but the expansion coefficient of scintillation crystal material is low, for example, the expansion coefficient of sodium iodide (NaI) is 47.4×10 -6 K -1 , the volume of scintillation crystal material changes greatly with temperature
The traditional quartz tube is in the shape of a cylinder with a pointed tip at the bottom. Due to the difference in expansion coefficient between the two, during the preparation of scintillation single crystals, the quartz tube is very easy to crack as the temperature changes. Once cracked, the air will flow from the When the cracks in the quartz tube enter the sample, the sample will be completely useless once it comes into contact with the air, resulting in the waste of all raw materials, time and energy consumed in the previous preparation process.
Even if the quartz tube is not cracked during the preparation process, it is still necessary to break the quartz tube to take out the crystal after the preparation is successful, so the quartz tube can only be used once, which will cause great waste
What's more serious is that after the quartz tube is broken, the crystal and the quartz tube are seriously adhered. Due to the adhesion force, the crystal has internal cracks and becomes a waste product. The failure rate of the entire preparation process is extremely high, which will cause a great waste of resources. technical problem

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for reducing breakage rate of quartz tubes during preparation of scintillation single crystals
  • Method for reducing breakage rate of quartz tubes during preparation of scintillation single crystals
  • Method for reducing breakage rate of quartz tubes during preparation of scintillation single crystals

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0039] The present invention will be described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited by the embodiments.

[0040] figure 2 It is a schematic diagram of the special-shaped quartz tube adopted in the present invention, image 3 It is a schematic diagram of the arrangement of quartz tubes in a single crystal furnace.

[0041] Take sodium iodide doped indium (NaI:In) scintillation single crystal material as an example:

[0042] (1) Quartz tube drawing

[0043] Choose a quartz tube with no defects and a smooth inner wall, wash it repeatedly with deionized water, dry it, and heat it to 1900-2000°C with an oxygen-hydrogen flame to soften the quartz tube, and draw it into a special-shaped quartz tube with a thick top and a thin bottom;

[0044] (2) Inner wall coating of special-shaped quartz tube

[0045] The above-mentioned special-shaped quartz tube is repeatedly washed with deionized wate...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
Login to View More

Abstract

The invention discloses a method for reducing the breakage rate of quartz tubes during the preparation of scintillation single crystals. The method comprises the following steps: drawing a quartz tubeinto a hetero-shaped quartz tube with a thick upper part and a thin lower part, coating the inner wall of the quartz tube with a film, mounting a strain gage on the outer wall of the quartz tube, controlling the growth speed of a single crystal through the feedback of strain amplitude, preventing the breakage of the quartz tube, inverting the hetero-shaped quartz tube after a crystal is formed, and taking out a scintillation crystal after the scintillation crystal is cooled to room temperature. The method has the advantages that the inner wall of the hetero-shaped quartz tube is coated with the film before a single crystal material is loaded, conglutination between the hetero-shaped quartz tube and the produced crystal can be avoided, complete separation of the produced crystal and the hetero-shaped quartz tube body is facilitated, the quartz tube can be prevented from directly extruding the crystal, the method is convenient for reducing micro defects of the crystal, the probability of self-absorption of the crystal is reduced, the cracking risk of the crystal is reduced, the internal performance of the scintillation crystal is obviously improved, in addition, after crystal growthand cooling after accomplished, the quartz tube is not required to be broken to take out the crystal, all that is needed is to open the quartz tube and pour out the crystal, and the quartz tube can be reused after being cleaned.

Description

technical field [0001] The invention belongs to the field of crystal material preparation, in particular to a method for reducing the damage rate of quartz tubes in the preparation of scintillation single crystals. Background technique [0002] Scintillation single crystal materials are usually wide bandgap semiconductor materials. When high-energy photons (such as ultraviolet rays, X-rays, and gamma rays) are incident, a series of complex interactions occur with the lattice of the material, including the photoelectric effect, Compton scattering, and electron pair effects. In this process, the conduction band and valence Many electron-hole pairs are formed in the band and are excited. Electron pairs and holes (eventually forming excitons) then move through the material and are trapped by defects in the forbidden band. Electrons and holes are trapped in the luminescent center and undergo radiative transitions to form scintillation luminescence. By scintillating single crys...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C30B11/00C30B29/12C30B29/46C23C14/35C23C14/06
CPCC23C14/0036C23C14/0652C23C14/35C30B11/002C30B11/006C30B29/12C30B29/46
Inventor 祁阳谭俊
Owner NORTHEASTERN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Eureka Blog
Learn More
PatSnap group products