JPH04102096A - Shielding body against thermal neutron - Google Patents
Shielding body against thermal neutronInfo
- Publication number
- JPH04102096A JPH04102096A JP21892990A JP21892990A JPH04102096A JP H04102096 A JPH04102096 A JP H04102096A JP 21892990 A JP21892990 A JP 21892990A JP 21892990 A JP21892990 A JP 21892990A JP H04102096 A JPH04102096 A JP H04102096A
- Authority
- JP
- Japan
- Prior art keywords
- ray
- thermal
- neutrons
- neutron
- shielding layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000002245 particle Substances 0.000 claims abstract description 21
- 230000005251 gamma ray Effects 0.000 claims abstract description 14
- 239000011347 resin Substances 0.000 claims abstract description 8
- 229920005989 resin Polymers 0.000 claims abstract description 8
- 150000001639 boron compounds Chemical class 0.000 claims abstract description 7
- 239000011159 matrix material Substances 0.000 abstract description 11
- XLYOFNOQVPJJNP-ZSJDYOACSA-N Heavy water Chemical compound [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 abstract description 8
- 229910052739 hydrogen Inorganic materials 0.000 abstract description 8
- 239000001257 hydrogen Substances 0.000 abstract description 8
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 abstract description 6
- 239000004809 Teflon Substances 0.000 abstract description 3
- 229920006362 Teflon® Polymers 0.000 abstract description 3
- 230000000717 retained effect Effects 0.000 abstract 1
- 230000005855 radiation Effects 0.000 description 12
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 5
- 229910052796 boron Inorganic materials 0.000 description 5
- 150000001875 compounds Chemical class 0.000 description 5
- 238000002601 radiography Methods 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 238000004364 calculation method Methods 0.000 description 3
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 3
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 2
- 239000004698 Polyethylene Substances 0.000 description 2
- 239000006096 absorbing agent Substances 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 150000002431 hydrogen Chemical class 0.000 description 2
- 238000003384 imaging method Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229910052744 lithium Inorganic materials 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- -1 polyethylene Polymers 0.000 description 2
- 229920000573 polyethylene Polymers 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000002745 absorbent Effects 0.000 description 1
- 239000002250 absorbent Substances 0.000 description 1
- 239000011358 absorbing material Substances 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004992 fission Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000001956 neutron scattering Methods 0.000 description 1
- 238000009659 non-destructive testing Methods 0.000 description 1
- 239000012188 paraffin wax Substances 0.000 description 1
- 229920002379 silicone rubber Polymers 0.000 description 1
- 239000004945 silicone rubber Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
この発明は、熱中性子を遮蔽するための熱中性子用遮蔽
体に関する。Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a thermal neutron shield for shielding thermal neutrons.
［従来の技術］
近時、中性子ラジオグラフィ （ＮＲＧ）による非破壊
検査及び中性子の散乱を利用した物質の分子構造解析等
の分野において、熱中性子を利用する技術が注目を集め
、各方面で種々研究されている。この場合に、中性子そ
の他の放射線を外部に漏らさないように、装置各部を遮
蔽体で覆う必要がある。[Prior Art] Recently, technology that uses thermal neutrons has attracted attention in fields such as non-destructive testing using neutron radiography (NRG) and molecular structure analysis of substances using neutron scattering, and has been used in various fields. being researched. In this case, it is necessary to cover each part of the device with a shield to prevent neutrons and other radiation from leaking to the outside.
第４図に示すように、従来の遮蔽体２は、線源９５の側
に中性子遮蔽層３が設けられ、この外側がガンマ線遮蔽
層４で覆われている。線源５から放射される中性子は遮
蔽層３で吸収され、ガンマ線は鉛製の遮蔽層４で吸収さ
れるようになっている。As shown in FIG. 4, in the conventional shielding body 2, a neutron shielding layer 3 is provided on the side of the radiation source 95, and the outside thereof is covered with a gamma ray shielding layer 4. Neutrons emitted from the radiation source 5 are absorbed by the shielding layer 3, and gamma rays are absorbed by the shielding layer 4 made of lead.
中性子遮蔽層３は、ポリエチレン、シリコーンゴム、ま
たはパラフィン等からなるマトリックス中にホウ素化合
物粒子（Ｂ２０３ 、Ｂ４Ｃ等）を所定の割合で分散さ
せたものである。ホウ素化合物粒子は、中性子を吸収す
る吸収材としての役割を有する。このような遮蔽体２に
おいては、中性子遮蔽層３のマトリックス中に多量の水
素が含まれており、これら水素原子によって高速中性子
が減速され、熱中性子（減速中性子）６となる。さらに
、熱中性子６はホウ素化合物粒子によって捕獲される。The neutron shielding layer 3 is made by dispersing boron compound particles (B203, B4C, etc.) in a predetermined ratio in a matrix made of polyethylene, silicone rubber, paraffin, or the like. The boron compound particles serve as an absorbent that absorbs neutrons. In such a shielding body 2, a large amount of hydrogen is contained in the matrix of the neutron shielding layer 3, and fast neutrons are slowed down by these hydrogen atoms to become thermal neutrons (decelerated neutrons) 6. Furthermore, thermal neutrons 6 are captured by boron compound particles.
［発明が解決しようとする課題］
しかしながら、従来の遮蔽体は、高速中性子に対しては
優れた遮蔽性能を示すが、低速の熱中性子に対する遮蔽
性能は必ずしも万全ではない。これは、中性子遮蔽層の
マトリックス中に多量の水素が含有されているために、
吸収材に熱中性子６が吸収されてしまう前に、熱中性子
６の一部が水素原子に捕獲されて、高エネルギの二次ガ
ンマ線７（工、ネルギレベルが約２．２ＭｅＶ）を放出
するからである。この高エネルギの二次ガンマ線７は、
ホウ素から放出される比較的低エネルギの二次ガンマ線
を遮蔽する程度の厚さの鉛遮蔽層４では十分に遮蔽でき
ない。このため、人体に有害な高エネルギ二次ガンマ線
７が外部に漏れ出し、実験者等が被爆するおそれが生じ
る。[Problems to be Solved by the Invention] However, although conventional shielding bodies exhibit excellent shielding performance against fast neutrons, their shielding performance against slow thermal neutrons is not necessarily perfect. This is because the matrix of the neutron shielding layer contains a large amount of hydrogen.
Before the thermal neutrons 6 are absorbed by the absorbing material, some of them are captured by hydrogen atoms and emit high-energy secondary gamma rays 7 (energy level is about 2.2 MeV). It is. This high-energy secondary gamma ray 7 is
The lead shielding layer 4, which is thick enough to shield relatively low-energy secondary gamma rays emitted from boron, cannot sufficiently shield them. Therefore, there is a risk that high-energy secondary gamma rays 7 harmful to the human body leak outside, exposing experimenters and others to radiation.
ここで、熱中性子とは、エネルギレベルが約１ｅＶ以下
のものをいい、高速中性子を減速材で減速させた低エネ
ルギ状態の中性子のことをいう。Here, the thermal neutron refers to a neutron with an energy level of about 1 eV or less, and refers to a low-energy neutron obtained by moderating a fast neutron with a moderator.
高速中性子は、炉心内の燃料の核分裂で放出された状態
で、通常、エネルギレベルがｌ Ｍ ｅ Ｖ以上である
。Fast neutrons are released by nuclear fission of fuel in a reactor core and typically have an energy level of 1 M e V or higher.
ところで、従来においては、高速中性子の遮蔽を主目的
としていたので、遮蔽体中に減速材としての水素の存在
は必要不可欠であり、高エネルギの二次ガンマ線の発生
を回避することはできない。By the way, in the past, since the main purpose was to shield fast neutrons, the presence of hydrogen as a moderator in the shielding body was essential, and the generation of high-energy secondary gamma rays could not be avoided.
しかし、近時、熱中性子の利用促進に伴い、熱中性子だ
けの遮蔽を行なうための遮蔽体が必要とされている。熱
中性子は、水素原子のみならず、鉄、アルミニウム等の
金属原子に捕獲されると、人体に有害な高エネルギの二
次ガンマ線を生じる。However, in recent years, as the use of thermal neutrons has been promoted, a shielding body for shielding only thermal neutrons is required. When captured by not only hydrogen atoms but also metal atoms such as iron and aluminum, thermal neutrons produce high-energy secondary gamma rays that are harmful to the human body.
この発明は、かかる事情に鑑みてなされたものであって
、人体に有害な高エネルギ二次ガンマ線を生じることな
く、熱中性子を遮蔽することができる熱中性子用遮蔽体
を提供することを目的とする。This invention was made in view of the above circumstances, and an object of the present invention is to provide a thermal neutron shield that can shield thermal neutrons without producing high-energy secondary gamma rays that are harmful to the human body. do.
［課題を解決するための手段及び作用コこの発明に係る
熱中性子用遮蔽体は、熱中性子を捕獲すると高エネルギ
の二次ガンマ線を発生する高エネルギ二次ガンマ線発生
元素を含まない樹脂の中に、熱中性子を吸収する熱中性
子吸収元素を含む粒子を分散させたことを特徴とする。[Means and Effects for Solving the Problems] The thermal neutron shield according to the present invention includes a resin containing no high-energy secondary gamma ray-generating element that generates high-energy secondary gamma rays when thermal neutrons are captured. , is characterized by dispersing particles containing a thermal neutron absorbing element that absorbs thermal neutrons.
熱中性子吸収元素を含む粒子にはＢ ２０３．８４Ｃ等
のホウ素系化合物を採用することが最も好ましい。Ｂは
、熱中性子を捕獲したときに、これから放出されるに次
ガンマ線が比較的低エネルギ（エネルベルが約０．５Ｍ
ｅＶ）である。このため、Ｂによれば人体に有害な高エ
ネルギ二次ガンマ線を放出することなく、熱中性子を吸
収することができる。また、ホウ素系化合物以外の他の
物質としてＬｉＦ等のリチウム系化合物を熱中性子吸収
元素を含む粒子に用いることもできる。It is most preferable to employ a boron-based compound such as B 203.84C for the particles containing a thermal neutron absorbing element. B is that when a thermal neutron is captured, the next gamma ray emitted from it has relatively low energy (the energy level is about 0.5M).
eV). Therefore, according to B, thermal neutrons can be absorbed without emitting high-energy secondary gamma rays that are harmful to the human body. Furthermore, a lithium-based compound such as LiF can also be used as a material other than a boron-based compound for particles containing a thermal neutron absorbing element.
従って、このようなホウ素系化合物およびリチウム系化
合物は、熱中性子吸収材として用いるのに好適である。Therefore, such boron-based compounds and lithium-based compounds are suitable for use as thermal neutron absorbers.
通常、遮蔽体として使用される材料の成分元素の内、高
エネルギ二次ガンマ線を発生する元素の典型的なものと
しては水素がある。水素以外の元素では、鉄、アルミニ
ウム等の金属があげられる。Among the constituent elements of materials normally used as shielding bodies, hydrogen is a typical element that generates high-energy secondary gamma rays. Elements other than hydrogen include metals such as iron and aluminum.
従って、これらの成分がマトリックスの樹脂中に含まれ
ないようにする必要がある。Therefore, it is necessary to prevent these components from being included in the matrix resin.
従って、マトリックスの樹脂には、フッ素系樹脂を用い
ることか好ましい。Therefore, it is preferable to use a fluororesin as the matrix resin.
一般に、フッ素樹脂は、ゴムやポリエチレンに比べて耐
放射線性の点で劣るといわれている。しかし、熱中性子
遮蔽体は、放射線レベルが比較的低い環境で使用される
こと、および、構造材料としての強度は要求されないこ
と、の理由から実用上不都合は生じない。Generally, fluororesins are said to have inferior radiation resistance compared to rubber and polyethylene. However, thermal neutron shields do not pose any practical disadvantages because they are used in environments where the radiation level is relatively low and strength as a structural material is not required.
［実施例］
以下、添付の図面を参照しながら、この発明の実施例に
ついて具体的に説明する。[Embodiments] Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings.
研究用原子炉の建屍に隣接して中性子ラジオグラフィ設
備が設けられている。原子炉プールには炉心が浸漬され
、炉心周囲に重水タンクが設けられている。重水タンク
から中性子ラジオグラフィ設備に至るまでの間に、ガラ
ス製の中性子導管が設けられており、熱中性子だけを取
り出すことができる。A neutron radiography facility is located adjacent to the research reactor building. The reactor core is immersed in the reactor pool, and a heavy water tank is installed around the reactor core. A glass neutron conduit is installed between the heavy water tank and the neutron radiography equipment, allowing only thermal neutrons to be extracted.
第２図に示すように、中性子導管１２の先端が中性子ラ
ジオグラフィ設備の撮影容器１１の入口に到達している
。撮影容器１１は鉄鋼材料でつくられている。容器１１
の入口にはシャッタ１３が設けられている。シャッタ１
３には熱中性子遮蔽体が張り付けられている。容器１１
の入口に対面するように感光板１５が設けられている。As shown in FIG. 2, the tip of the neutron conduit 12 has reached the entrance of the imaging container 11 of the neutron radiography equipment. The photographic container 11 is made of steel material. Container 11
A shutter 13 is provided at the entrance. shutter 1
3 is attached with a thermal neutron shield. Container 11
A photosensitive plate 15 is provided so as to face the entrance.
感光板１５は、熱中性子遮蔽体を有する部材１６でバッ
クアップされている。容器入口から感光板１５までの間
にはカプセル状の被検体１４が載置され、入口から入射
した熱中性子６が被検体１４に当たるようになっている
。The photosensitive plate 15 is backed up by a member 16 having a thermal neutron shield. A capsule-shaped specimen 14 is placed between the entrance of the container and the photosensitive plate 15, so that thermal neutrons 6 incident from the entrance hit the specimen 14.
次に、第１図に示すモデルを参照して熱中性子遮蔽体に
ついて説明する。なお、上記の遮蔽シャッタ１３および
遮蔽部材１６は、これと実質的に同様の構成をなすもの
である。Next, the thermal neutron shield will be explained with reference to the model shown in FIG. Note that the shielding shutter 13 and shielding member 16 described above have substantially the same configuration as this.
中性子遮蔽体２０は、線源５の側に中性子遮蔽層２３を
、その外側にガンマ線遮蔽層２４ををする。中性子遮蔽
層２３は、マトリックスにテフロン等のフッ素系樹脂を
用い、この樹脂中にＢ４Ｃ粒子を分散させて形成されて
いる。８４Ｃ粒子は、平均粒径が５１で、平均分布率が
２Ｘ１０９個／ａｍ３である。この場合に、８４Ｃ粒子
とマトリックス樹脂との混合比は重量比で約１対９であ
る。The neutron shielding body 20 has a neutron shielding layer 23 on the side of the radiation source 5 and a gamma ray shielding layer 24 on the outside thereof. The neutron shielding layer 23 is formed by using a fluororesin such as Teflon as a matrix and dispersing B4C particles in this resin. The 84C particles have an average particle size of 51 and an average distribution rate of 2×10 9 particles/am 3 . In this case, the mixing ratio of 84C particles and matrix resin is approximately 1:9 by weight.
次に、第１図および第３図を参照しながら熱中性子遮蔽
体の機能について説明する。Next, the function of the thermal neutron shield will be explained with reference to FIGS. 1 and 3.
遮蔽シャッタ１３を開け、重水タンクから導管１２を介
して熱中性子６を被検体１４に所定時間たけ照射する。The shielding shutter 13 is opened, and the subject 14 is irradiated with thermal neutrons 6 from the heavy water tank through the conduit 12 for a predetermined period of time.
熱中性子６は、被検体１４を透過し、後方の感光板１５
を感光させる。遮蔽部材１６に含まれるＢ４Ｃ粒子２５
に熱中性子６が当たると、これが粒子２５に捕獲され、
かわりに低エネルギの二次ガンマ線７が放出される。こ
の二次ガンマ線７は、保有エネルギが約０．５ＭｅＶ程
度であるので、外側の鉛遮蔽層２４によって十分に遮蔽
され得る。The thermal neutron 6 passes through the object 14 and hits the photosensitive plate 15 at the rear.
expose to light. B4C particles 25 contained in the shielding member 16
When thermal neutron 6 hits, it is captured by particle 25,
Instead, low-energy secondary gamma rays 7 are emitted. Since this secondary gamma ray 7 has an energy of about 0.5 MeV, it can be sufficiently shielded by the outer lead shielding layer 24.
また、中性子遮蔽層２３のマトリックスに水素を含まな
いので、熱中性子６が粒子２５に捕獲吸収されてしまう
間に、熱中性子６の一部がマトリックスに当たって高エ
ネルギ二次ガンマ線が生しることはない。この結果、撮
影容器１１の外部への放射線漏洩量か大幅に低減される
。Furthermore, since the matrix of the neutron shielding layer 23 does not contain hydrogen, while the thermal neutrons 6 are captured and absorbed by the particles 25, there is no chance that some of the thermal neutrons 6 will hit the matrix and generate high-energy secondary gamma rays. do not have. As a result, the amount of radiation leaking to the outside of the imaging container 11 is significantly reduced.
次に、第１図および第２図に示すモデルを用いて輸送計
算コードＡＮＩＳＮにより模擬計算を行ない、本発明と
従来とを理論的に比較した場合について説明する。Next, a case will be described in which a simulation calculation is performed using the transportation calculation code ANISN using the models shown in FIGS. 1 and 2, and a theoretical comparison is made between the present invention and the conventional method.
遮蔽体の形状および寸法、ホウ素の原子個数密度、並び
に線源の強さの条件を同じにして、両者を比較した。こ
の場合に、中性子吸収層３ではホウ素化合物２０重量％
に対してポリエチレン８０重量％の割合に、中性子吸収
層２３ではホウ素化合物１０重量９６に対してテフロン
９０重量％の割合とした。線Ｆｉ、５の径は１ｃＩＴｌ
で、中性子放出量は毎秒３ Ｘ １０１０とした。中性
子遮蔽層３．２３は、内径を５ ｃｍ 、厚さを５印と
した。鉛遮蔽層４゜２４は、内径を１０ｃｍ、厚さを１
０ｃｍとした。なお、線源５と中性子遮蔽層３．２３の
間には空気が存在するとした。The two were compared under the same conditions, including the shape and dimensions of the shield, the boron atomic number density, and the strength of the radiation source. In this case, the neutron absorption layer 3 contains 20% by weight of a boron compound.
In the neutron absorbing layer 23, the ratio of Teflon was 90% by weight to 10% by weight of the boron compound. The diameter of the wire Fi, 5 is 1cITl
The amount of neutrons emitted was 3 x 1010 per second. The neutron shielding layer 3.23 had an inner diameter of 5 cm and a thickness of 5 marks. The lead shielding layer 4゜24 has an inner diameter of 10 cm and a thickness of 1.
It was set to 0 cm. It is assumed that air exists between the radiation source 5 and the neutron shielding layer 3.23.
上記モデルを用いた模擬計算の結果によれば、鉛遮蔽層
の外表面おけるガンマ線の線量等量率は、本発明の遮蔽
体では従来の遮蔽体の約１／１０に低■する。線量等量
率を同程度とすれば、本発明の遮蔽体では、外側の鉛遮
蔽層の厚さを従来の約１／２まで薄くすることが可能に
なる。According to the results of simulation calculations using the above model, the dose equivalent rate of gamma rays on the outer surface of the lead shielding layer is about 1/10 lower in the shielding body of the present invention than in the conventional shielding body. If the dose equivalent rate is kept at the same level, in the shielding body of the present invention, the thickness of the outer lead shielding layer can be reduced to about 1/2 of that of the conventional shielding body.
また、上記実施例の遮蔽体は、従来のものより耐熱性に
優れ、約２００℃までの温度で使用可能である。Further, the shield of the above embodiment has better heat resistance than the conventional shield and can be used at temperatures up to about 200°C.
［発明の効果コ
本発明の熱中性子用遮蔽体によれば、高エネルギの二次
ガンマ線の発生量を従来のものより大幅に低減すること
ができる。このため、従来のものよりも放射線遮蔽性能
が向上し、同程度の遮蔽性能であれば、外側の鉛遮蔽層
の厚さを大幅に薄くすることが可能になり、遮蔽体を軽
量化できる。[Effects of the Invention] According to the thermal neutron shield of the present invention, the amount of high-energy secondary gamma rays generated can be significantly reduced compared to conventional shields. Therefore, the radiation shielding performance is improved compared to the conventional one, and with the same level of shielding performance, it is possible to significantly reduce the thickness of the outer lead shielding layer, and the weight of the shield can be reduced.
また、本発明の遮蔽体は、従来のものより加工性か良好
である。さらに、耐熱性に優れ、水素を含まないので不
燃性であり、長期間の使用に耐えられる。Further, the shielding body of the present invention has better workability than conventional shielding bodies. Furthermore, it has excellent heat resistance, is nonflammable because it does not contain hydrogen, and can withstand long-term use.
第１図はこの発明の実施例に係る熱中性子用遮蔽体を示
す断面模式図、第２図は中性子ラジオグラフィ装置の一
部を示す断面模式図、第３図は熱中性子の吸収挙動を説
明するために、中性子遮蔽層の一部を拡大して示す概念
図、第４図は従来の遮蔽体を示す断面模式図である。
５・・・線源、６・・・中性子、７・・・二次ガンマ線
、１３．１６．２０・・・遮蔽体、２３・・・中性子遮
蔽層、２４・・・ガンマ線遮蔽層、２５・・・熱中性子
吸収材。Fig. 1 is a schematic cross-sectional diagram showing a thermal neutron shield according to an embodiment of the present invention, Fig. 2 is a schematic cross-sectional diagram showing a part of a neutron radiography device, and Fig. 3 explains the absorption behavior of thermal neutrons. FIG. 4 is a schematic cross-sectional view showing a conventional shielding body. 5... Radiation source, 6... Neutron, 7... Secondary gamma ray, 13.16.20... Shielding body, 23... Neutron shielding layer, 24... Gamma ray shielding layer, 25. ...Thermal neutron absorber.
Claims (2)
を発生する高エネルギ二次ガンマ線発生元素を含まない
樹脂の中に、熱中性子を吸収する熱中性子吸収元素を含
む粒子を分散させたことを特徴とする熱中性子用遮蔽体
。(1) Particles containing a thermal neutron absorbing element that absorbs thermal neutrons are dispersed in a resin that does not contain a high energy secondary gamma ray generating element that generates high energy secondary gamma rays when absorbing thermal neutrons. Features a thermal neutron shield.
あることを特徴とする請求項１記載の熱中性子用遮蔽体
。(2) The thermal neutron shield according to claim 1, wherein the particles containing the thermal neutron absorbing element are boron compounds.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21892990A JPH04102096A (en) | 1990-08-22 | 1990-08-22 | Shielding body against thermal neutron |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21892990A JPH04102096A (en) | 1990-08-22 | 1990-08-22 | Shielding body against thermal neutron |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04102096A true JPH04102096A (en) | 1992-04-03 |
Family
ID=16727534
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21892990A Pending JPH04102096A (en) | 1990-08-22 | 1990-08-22 | Shielding body against thermal neutron |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04102096A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007047096A (en) * | 2005-08-12 | 2007-02-22 | Hitachi Ltd | Radioisotope manufacturing equipment and its installation method |
| JP2014055854A (en) * | 2012-09-12 | 2014-03-27 | High Energy Accelerator Research Organization | Neutron absorber and neutron exposure preventing structure |
| JP2017026563A (en) * | 2015-07-28 | 2017-02-02 | 株式会社▲高▼田機械製作所 | Neutron shielding material, method for manufacturing the same, and neutron shielding container |
-
1990
- 1990-08-22 JP JP21892990A patent/JPH04102096A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007047096A (en) * | 2005-08-12 | 2007-02-22 | Hitachi Ltd | Radioisotope manufacturing equipment and its installation method |
| JP2014055854A (en) * | 2012-09-12 | 2014-03-27 | High Energy Accelerator Research Organization | Neutron absorber and neutron exposure preventing structure |
| JP2017026563A (en) * | 2015-07-28 | 2017-02-02 | 株式会社▲高▼田機械製作所 | Neutron shielding material, method for manufacturing the same, and neutron shielding container |
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