CN103995280B - A kind of neutron detector boron film negative electrode and preparation method thereof - Google Patents
A kind of neutron detector boron film negative electrode and preparation method thereof Download PDFInfo
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- CN103995280B CN103995280B CN201410197126.2A CN201410197126A CN103995280B CN 103995280 B CN103995280 B CN 103995280B CN 201410197126 A CN201410197126 A CN 201410197126A CN 103995280 B CN103995280 B CN 103995280B
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- negative electrode
- boron
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- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 title claims abstract description 67
- 229910052796 boron Inorganic materials 0.000 title claims abstract description 53
- 238000002360 preparation method Methods 0.000 title claims abstract description 7
- 239000010408 film Substances 0.000 claims abstract description 44
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 13
- 239000002994 raw material Substances 0.000 claims abstract description 11
- 239000003960 organic solvent Substances 0.000 claims abstract description 8
- 239000010409 thin film Substances 0.000 claims abstract description 6
- 238000000576 coating method Methods 0.000 claims description 11
- 239000011248 coating agent Substances 0.000 claims description 10
- 239000012530 fluid Substances 0.000 claims description 9
- 239000000203 mixture Substances 0.000 claims description 8
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 claims description 5
- -1 phenolic aldehyde amine Chemical class 0.000 claims description 5
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 4
- WQPDQJCBHQPNCZ-UHFFFAOYSA-N cyclohexa-2,4-dien-1-one Chemical compound O=C1CC=CC=C1 WQPDQJCBHQPNCZ-UHFFFAOYSA-N 0.000 claims description 3
- 239000012467 final product Substances 0.000 claims description 3
- 125000000896 monocarboxylic acid group Chemical group 0.000 claims description 3
- 239000007921 spray Substances 0.000 claims description 3
- 239000012745 toughening agent Substances 0.000 claims description 3
- FDPIMTJIUBPUKL-UHFFFAOYSA-N dimethylacetone Natural products CCC(=O)CC FDPIMTJIUBPUKL-UHFFFAOYSA-N 0.000 claims description 2
- 150000007984 tetrahydrofuranes Chemical group 0.000 claims description 2
- NIQCNGHVCWTJSM-UHFFFAOYSA-N Dimethyl phthalate Chemical compound COC(=O)C1=CC=CC=C1C(=O)OC NIQCNGHVCWTJSM-UHFFFAOYSA-N 0.000 claims 2
- FBSAITBEAPNWJG-UHFFFAOYSA-N dimethyl phthalate Natural products CC(=O)OC1=CC=CC=C1OC(C)=O FBSAITBEAPNWJG-UHFFFAOYSA-N 0.000 claims 1
- 229960001826 dimethylphthalate Drugs 0.000 claims 1
- 239000007787 solid Substances 0.000 claims 1
- 238000001514 detection method Methods 0.000 abstract description 21
- 239000000853 adhesive Substances 0.000 abstract description 9
- 230000001070 adhesive effect Effects 0.000 abstract description 9
- 239000011159 matrix material Substances 0.000 abstract description 2
- 239000002184 metal Substances 0.000 abstract description 2
- 238000001228 spectrum Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 7
- 229920001903 high density polyethylene Polymers 0.000 description 5
- 239000004700 high-density polyethylene Substances 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 238000001035 drying Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 239000004698 Polyethylene Substances 0.000 description 2
- 229920000573 polyethylene Polymers 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- LDCRTTXIJACKKU-ONEGZZNKSA-N dimethyl fumarate Chemical compound COC(=O)\C=C\C(=O)OC LDCRTTXIJACKKU-ONEGZZNKSA-N 0.000 description 1
- 229960004419 dimethyl fumarate Drugs 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000005251 gamma ray Effects 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 230000000155 isotopic effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 238000010422 painting Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
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Abstract
The invention discloses a kind of neutron detector boron film negative electrode and preparation method thereof.Neutron detector boron film negative electrode, is a kind of detector negative electrode with good electrical performance and neutron-sensitive performance.Negative electrode uses conducting metal Al matrix, and cathode surface is covered with neutron-sensitive thin film, and the raw material components of neutron-sensitive thin film includes: 100 parts of boron powder, 15 25 parts7 12 parts of firming agent and 30 40 parts of organic solvents, described number is mass fraction.One neutron detector boron film negative electrode of the present invention, prepares simple, with low cost, and adhesive force is high, uniformity is good, and the detection efficient of gained detector is high.
Description
Technical field
The present invention relates to a kind of neutron detector boron film negative electrode and preparation method thereof.
Background technology
The detection of neutron is occupying special status in Detection Techniques, and it is than charged particle or gamma-ray detection difficulty
Much, mainly interacted by it and atomic nucleus and produce charged particle or γ photon realizes.It is coated with boron gas in recent years to visit
Survey device to compare and fill 3He or BF3 detector advantage and show especially, be increasingly becoming a kind of main neutron detection instrument.Quantitatively it is coated with boron negative electrode skill
Art is the most important thing making and being coated with boron gas detector, is related to the determination of detector performance parameters and uses the choosing of environment
Select.
Start late because being coated with the development of boron detector, the fewest and existing about being quantitatively coated with the report of boron cathode technique both at home and abroad
There is poor adhesive force, lack of homogeneity in the negative electrode boron film in technology, thus affects the detection efficient of detector.
Summary of the invention
The present invention newly provides a kind of neutron detector boron film negative electrode and preparation method thereof.
For solving above-mentioned technical problem, the invention of this reality adopts the following technical scheme that
A kind of neutron detector boron film negative electrode, cathode surface is covered with neutron-sensitive thin film, the raw material group of neutron-sensitive thin film
Divide and include: 100 parts of boron powder, 15-25 parts
7-12 part firming agent and 30-40 part organic solvent, described number is mass fraction.
Above-mentioned negative electrode is conductive cathode, it is preferred to use conducting metal Al matrix, first pretreatment, above-mentioned neutron detection before film
Device boron film negative electrode, for neutron detection, the detector negative electrode with good electrical performance and neutron-sensitive performance.
Applicant it has been investigated that: negative electrode, through polishing, cleaning, after the process such as drying processes, uses above-mentioned raw materials component,
After solvent modulation, bridging agent modulation, coating, cold treatment and drying course, available uniform and stable boron film, and thickness can
Control；Boron crosses boron layer at least cannot firmly be coated in region to be coated, and boron too much can cause the in uneven thickness of boron film；Before being coated with boron, solution must
Must adjust uniformly, if there is graininess boron powder, easily make the boron film of shaping produce protruding boron powder particles, protruding place is being visited
Survey in device test and may cause peak discharge phenomenon after high voltage；
Consumption too much can increase outgoing particle
The loss of energy, reduces detection efficient, and very few adhesive force is inadequate.
The material component of above-mentioned neutron detector boron film negative electrode also includes 3-5 part toughener, and described number is mass fraction.
So can further enhance the adhesive force of gained film, uniformity, ensure detection efficient simultaneously.
The raw material components of above-mentioned neutron detector boron film negative electrode also includes 6-8 part HO-[-CH2-NH-CO-NH-CH2-O]n-
H, 1-2 part (COOH) 2 and 0.8-1 part C6H6O, described number is mass fraction, the preferred 70-120 of above-mentioned n.So can more enter one
Step strengthens the adhesive force of gained film, uniformity, improves the detection efficient of detector simultaneously.
The raw material group raw material components of above-mentioned neutron detector boron film negative electrode also includes 3-4 partAnd 0.5-
0.8 part of C36H70CaO, wherein R1 isDescribed number is mass fraction.So can ensure that boron film is uniform
While property, adhesive force, it is ensured that the susceptiveness of detector.
Above-mentionedMiddle n value is 1-3.
Boron powder needs chemical purity and two aspects of isotopic purity, and wherein chemical purity is better than more than 95%, B10 abundance
Not less than 90%.So can be further ensured that the detection efficient of detector.
Above-mentioned firming agent preferably polyetheramine firming agent and phenolic aldehyde amine curing agent mass ratio are the mixture of 1.1-1.3.
So can be further ensured that adhesive force and the drying efficiency of boron film.
Above-mentioned organic solvent is preferably oxolane, dimethyl fumarate, dimethyl sulfoxide or acetone.
The thickness of above-mentioned boron film is preferably 2.5-3.5um, is 0.62-0.82mg/cm2.So can make the spy of detector
Survey efficiency and reach optimum.
The preparation method of above-mentioned neutron detector boron film negative electrode, the following steps including connected in order:
A, cathode treatment: negative electrode is polished, polishes, cleans, dried；
B, by addition to boron powder raw material components mix, obtain coating fluid；
C, by after one layer of coating fluid of even spread on negative electrode, uniformly spray boron powder, the most again last layer coating fluid；
D, by step C gained 92-96 DEG C be incubated 2-2.5 hour, to obtain final product.
Applicant it has been investigated that: use said method relative to methods such as immersion coatings, can significantly save various tree
The consumption of fat, organic solvent etc., and gained boron film is uniform, detection efficient is high is the most cost-effective but also can improve detection efficient
The best approach.
Comprising the neutron detector of above-mentioned neutron detector boron film negative electrode, working gas is 90%Ar and 10%CH4Mixed
Compound.
Above-mentioned gas ionization potential is low, and the drift velocity of electronics is big, and electron adsorption effect is little, it is simple to improve the collection of electronics
Efficiency；And conveniently storage, transport, do not damage health.
The NM technology of the present invention is prior art.
One neutron detector boron film negative electrode of the present invention, prepares simple, with low cost, and adhesive force is high, uniformity is good, gained
The detection efficient of detector is high.
Figure of description
Fig. 1 is the graph of a relation of ionization chamber detection efficient and boron film linear thickness.
Fig. 2 is the schematic diagram of gained boron film on stainless steel substrates in embodiment 1.
Fig. 3 is the detection efficient that embodiment 1 makes boron film negative electrode proportional counter by oneself.
Detailed description of the invention
In order to be more fully understood that the present invention, it is further elucidated with present disclosure below in conjunction with embodiment, but the present invention
Content is not limited solely to the following examples.
Embodiment 1
Being coated with boron film on stainless steel substrates as follows, following steps are connected in order:
A, cathode treatment: negative electrode is polished, polishes, cleans, dried；
B, by addition to boron powder raw material components mix, obtain coating fluid；
C, by after one layer of coating fluid of even spread on negative electrode, uniformly spray boron powder, the most again last layer coating fluid；
D, by step C gained 92-96 DEG C be incubated 2-2.5 hour, to obtain final product.
The raw material components of neutron detector boron film negative electrode includes: 100 parts of boron powder (Dalian Bo Entan science and technology
The amorphous enrichment 10B boron powder (10B abundance 90%, B content 95%) of company limited, 20 parts(meansigma methods of n is 2.3), 10 parts of solidifications
Agent (polyetheramine firming agent D400 and phenolic aldehyde amine curing agent TZ500 mass ratio are the mixture of 1.2), 35 parts of organic solvents, 4 parts
Toughener (QS-BE), 7 parts of part structural formulas are HO-[-CH2-NH-CO-NH-CH2-O] n-H resin (powdery, n is 80-100, prick
Western Jebb chemical industry), 1.5 parts (COOH) 2,0.9 part of C6H6O, 3.5 partsWith 0.6 part of C36H70CaO, wherein R1
ForDescribed number is mass fraction.
Organic solvent is dimethyl sulfoxide；The thickness of boron film is 3um.
Said method gained boron film adhesive force is high, uniformity is good, and the detection efficient of gained neutron detector is high, neutron detection
The working gas of device is 90%Ar and 10%CH4Mixture.
Use said method, made by oneself a kind of at proportional counter enumerator inwall (proportional counter negative electrode) attachment last layer B10 film,
As thermal neutron sensitive layer.Meanwhile, the homemade painting sensitive proportional counter of boron thermal neutron is placed into standard241In Am-Be neutron source
Carry out experiment to measure.Under 800V high pressure respectively with thick for 7mm and 20mm cylindrical high density polyethylene (HDPE) (HDPE winding pipe A type,
Hangzhou Liantong Tube Co., Ltd.) sleeve pipe parcel proportional counter, record two groups of neutron spectra of proportional counter in 1000 seconds；Remove highly dense again
The neutron spectra of naked proportional coumter is recorded under the same terms after degree polyethylene cannula.Analyze three groups of spectrums with multiple tracks software ums to draw
The area under spectrum of each spectrum, entirely compose counting, average energy and counting rate data and be listed in the table below 1.
The detection efficient of self-control boron film negative electrode proportional counter corresponding standard A m-Be neutron source is 0.24%.Am-Be neutron
The average neutron energy in source is 4MeV, for fast neutron source.Boron film negative electrode is that thermal neutron (0.025eV) is sensitive.Calculate and obtain difference
The detection efficient of the self-control boron film negative electrode proportional counter that monoenergetic neutrons is corresponding is shown in Fig. 3.
Neutron spectra parameter after table 1 polyethylene tube parcel proportional coumter
| Measuring condition | Area under spectrum (S) | Entirely compose counting (C) | Average energy (S/C) | Counting rate (C/T)/cps |
| Naked proportional counter | 6219 | 7394 | 0.841 | 7.39 |
| Parcel 7mm thickness HDPE | 5750 | 7635 | 0.753 | 7.64 |
| Parcel 20mm thickness HDPE | 6745 | 9283 | 0.727 | 9.28 |
Note: the data in form are in addition to full spectrum counting and counting rate, and unit is relative unit.
For neutron field, the neutron energy launched because of Am-Be neutron source is mostly up to MeV magnitude, with boron in proportional counter
Membrane interaction cross section is the least, and in the case of proportional coumter naked pipe, counting rate is relatively low.Proportional counter outer wrapping high density is gathered
Pvdf layer is the thickest, and the energy that neutron loses wherein is the most, enters the neutron energy in proportional counter the lowest, is detected
Probability is the highest, thus counting rate is of a relatively high.And for γ field, the counting rate of γ photon is to present such trend
's.This is also just with it is demonstrated experimentally that the signal that proportional counter recorded is strictly the signal of neutron.
Claims (7)
1. a neutron detector boron film negative electrode, it is characterised in that: cathode surface is covered with neutron-sensitive thin film, neutron-sensitive thin film
Raw material components include: 100 parts of boron powder, 15-25 parts7-12 part is solid
Agent, 30-40 part organic solvent, 3-5 part toughener, 6-8 part HO-[-CH2-NH-CO-NH-CH2-O] n-H, 1-2 part
(COOH)2, 0.8-1 part C6H6O, 3-4 partWith 0.5-0.8 part C36H70CaO, wherein R1 isDescribed number is mass fraction.
2. neutron detector boron film negative electrode as claimed in claim 1, it is characterised in that:
Middle n value is 1-3.
3. neutron detector boron film negative electrode as claimed in claim 1 or 2, it is characterised in that: in boron powder, B10 abundance is not less than
90%.
4. neutron detector boron film negative electrode as claimed in claim 1 or 2, it is characterised in that: firming agent is polyetheramine firming agent
It is the mixture of 1.1-1.3 with phenolic aldehyde amine curing agent mass ratio.
5. neutron detector boron film negative electrode as claimed in claim 1 or 2, it is characterised in that: organic solvent is oxolane, richness
Horse dimethyl phthalate, dimethyl sulfoxide or acetone；The thickness of boron film is 2.5-3.5 μm.
6. the preparation method of the neutron detector boron film negative electrode described in claim 1-5 any one, it is characterised in that: include suitable
The following steps that sequence connects:
A, cathode treatment: negative electrode is polished, polishes, cleans, dried；
B, by addition to boron powder raw material components mix, obtain coating fluid；
C, by after one layer of coating fluid of even spread on negative electrode, uniformly spray boron powder, the most again last layer coating fluid；
D, by step C gained 92-96 DEG C be incubated 2-2.5 hour, to obtain final product.
7. comprise the neutron detector of neutron detector boron film negative electrode described in claim 1-5 any one, it is characterised in that:
Working gas is 90%Ar and 10%CH4Mixture.
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| CN105137473A (en) * | 2015-07-21 | 2015-12-09 | 时天成 | Production method for boron-10 element used for neutron detector |
| CN106199681B (en) * | 2016-06-24 | 2018-11-02 | 西北核技术研究所 | A kind of nuclear reaction radiation conversion target and preparation method thereof and a kind of offset-type neutron detector |
| CN110467865B (en) | 2018-05-09 | 2021-12-28 | 同方威视技术股份有限公司 | Boron coating method |
| CN112859142B (en) * | 2021-01-25 | 2023-01-24 | 核工业西南物理研究院 | Preparation method of tube wall neutron sensitive layer and proportional counter tube |
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| CN102749641B (en) * | 2011-04-18 | 2015-11-25 | 同方威视技术股份有限公司 | Be coated with boron neutron detector and manufacture method thereof |
| FR2975108A1 (en) * | 2011-05-12 | 2012-11-16 | Onectra | BORON DEPOSITION METHOD ON A METAL SHEET FOR NEUTRON DETECTION APPARATUS OR IONIZATION CHAMBER |
| US8502157B2 (en) * | 2011-09-09 | 2013-08-06 | General Electric Company | Boron containing coating for neutron detection |
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| 《含碳化硼的吸收和屏蔽中子辐射涂料的研究》;黄益平等;《天津大学学报》;20110731;第44卷(第7期);第639-643页 * |
| 《浸酯涂硼_中子探测器灵敏层制作方法》;陈国云等;《原子能科学技术》;20130331;第47卷(第3期);第486-489页、表2、图1-3 * |
| 《涂硼电离室中子探测效率和灵敏度》;陈国云等;《原子能科学技术》;20110228;第45卷(第2期);245页第1栏 * |
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