1
Perfect Neutron Reflector - Computer Simulation (for Susan)
Perfect Neutron Reflector - Computer Simulation (for Susan)
DATE: 2012/07/18::
2
Beryllium oxide - The Russian Hahn David
Beryllium oxide - The Russian Hahn David's channel
DATE: 2012/09/20::
3
Feed the beast- Mindcrack: Ep. 118 -Neutron Reflectors Are Breaking Bad
Feed the beast- Mindcrack: Ep. 118 -Neutron Reflectors Are Breaking Bad
DATE: 2014/01/19::
4
Rarpack Episode 12: I fixed the reflectors!
Rarpack Episode 12: I fixed the reflectors!
DATE: 2014/10/16::
5
Mods per Negati: IndustrialCraft Parte 9B: Seconda Parte sull
Mods per Negati: IndustrialCraft Parte 9B: Seconda Parte sull'Energia Nucleare! [Tutorial ITA]
DATE: 2012/09/29::
6
Idea: Complementary Transmutation Nuclear Reactor
Idea: Complementary Transmutation Nuclear Reactor
DATE: 2012/07/13::
7
Minecraft 1.4.7 Industrialcraft 2 Modreview/Tutorial Deutsch/German Crafting/Erklärung AKW Teil 3
Minecraft 1.4.7 Industrialcraft 2 Modreview/Tutorial Deutsch/German Crafting/Erklärung AKW Teil 3
DATE: 2013/08/06::
8
Fictionalized Criticality Accident
Fictionalized Criticality Accident
DATE: 2007/12/27::
9
Minecraft Industrial Craft 2 Microcycle Nuclear Reactor Design(Generator, Breeder)
Minecraft Industrial Craft 2 Microcycle Nuclear Reactor Design(Generator, Breeder)
DATE: 2013/11/20::
10
Response to iSuperiorReviews Questions
Response to iSuperiorReviews Questions
DATE: 2013/05/10::
11
First Test
First Test
DATE: 2014/11/24::
12
TekkitPedia Episodio 10 - IC2 - Giochicchiando con il Nuclear Reactor e i suoi Components
TekkitPedia Episodio 10 - IC2 - Giochicchiando con il Nuclear Reactor e i suoi Components
DATE: 2013/03/26::
13
ReactorCraft Tutorial #6.1 - 12 Core Fission Reactor
ReactorCraft Tutorial #6.1 - 12 Core Fission Reactor
DATE: 2014/09/11::
14
Minecraft Nuclear reactor Autoloader system for 1.4.5. Industrial Craft Nuclear Reactor Mark 1 EA*
Minecraft Nuclear reactor Autoloader system for 1.4.5. Industrial Craft Nuclear Reactor Mark 1 EA*
DATE: 2013/02/10::
15
Моды на компьютер Майнкрафт 1.4.7
Моды на компьютер Майнкрафт 1.4.7
DATE: 2015/01/31::
16
Minecraft Mod Twilight Forest
Minecraft Mod Twilight Forest
DATE: 2015/03/01::
17
Monster Craft смотреть
Monster Craft смотреть
DATE: 2015/02/08::
18
Сборка Кейна Видео Minecraft
Сборка Кейна Видео Minecraft
DATE: 2015/04/12::
19
Смотреть прохождение Майнкрафт 2
Смотреть прохождение Майнкрафт 2
DATE: 2015/02/19::
20
Neutrons_Cadmium.avi
Neutrons_Cadmium.avi
DATE: 2009/11/15::
21
ReactorCraft Tutorial #6 - 6 Core Fission Reactor
ReactorCraft Tutorial #6 - 6 Core Fission Reactor
DATE: 2014/09/09::
22
Porcelana "Reflector"
Porcelana "Reflector"
DATE: 2010/06/17::
23
Fukushima Needs World Wide Help Big Time
Fukushima Needs World Wide Help Big Time
DATE: 2013/09/25::
24
Professor Steven Jones cold fusion energy on Cancel The Cabal
Professor Steven Jones cold fusion energy on Cancel The Cabal
DATE: 2013/05/18::
25
ThruNite Neutron 1A review - Short Version
ThruNite Neutron 1A review - Short Version
DATE: 2012/11/23::
26
Stippling a flashlight reflector
Stippling a flashlight reflector
DATE: 2012/09/29::
27
ThruNite Neutron 1A review, OH YEAH!!
ThruNite Neutron 1A review, OH YEAH!!
DATE: 2011/02/09::
28
ThruNite Neutron 1C 2C XM-L Flashlight Review
ThruNite Neutron 1C 2C XM-L Flashlight Review
DATE: 2011/02/16::
29
Neutron moderator
Neutron moderator
DATE: 2014/11/14::
30
Thrunite Catapult V3 XML Led (Smooth Reflector)
Thrunite Catapult V3 XML Led (Smooth Reflector)
DATE: 2011/04/05::
31
Silicon optics, windows, lenses, prisms, crystals, wafers sales@dmphotonics.com
Silicon optics, windows, lenses, prisms, crystals, wafers sales@dmphotonics.com
DATE: 2013/06/18::
32
(1/2) Astronomers Discover Most Massive Neutron Star Yet Known - Part I: Discovery
(1/2) Astronomers Discover Most Massive Neutron Star Yet Known - Part I: Discovery
DATE: 2010/10/27::
33
Astronomy - Cleaning a Telescope Mirror Safely
Astronomy - Cleaning a Telescope Mirror Safely
DATE: 2010/09/07::
34
ThruNite TN-32 - 1700 Lumen Flashlight - Demo & Review
ThruNite TN-32 - 1700 Lumen Flashlight - Demo & Review
DATE: 2014/10/19::
35
Neutron v2 style with precession - Down/Down/Up
Neutron v2 style with precession - Down/Down/Up
DATE: 2013/06/13::
36
Five group delayed neutron calculation
Five group delayed neutron calculation
DATE: 2012/08/29::
37
How To Make a DIY SteadyCam Tutorial By [ Neutron Studios]
How To Make a DIY SteadyCam Tutorial By [ Neutron Studios]
DATE: 2012/05/26::
38
THRUNITE TC10 Rechargeable 900 Lumens / PrepperKip
THRUNITE TC10 Rechargeable 900 Lumens / PrepperKip
DATE: 2015/03/24::
39
ThruNite T30S V2
ThruNite T30S V2
DATE: 2014/10/30::
40
Reactorcraft Fission Power Plant Tutorial, Design Guide
Reactorcraft Fission Power Plant Tutorial, Design Guide
DATE: 2014/07/07::
41
Spark SD73-CW & NW Headlamp Review
Spark SD73-CW & NW Headlamp Review
DATE: 2012/05/04::
42
Lumapower Signature LX Video Review at night with both Tele-Force Head and standard reflector
Lumapower Signature LX Video Review at night with both Tele-Force Head and standard reflector
DATE: 2011/02/12::
43
First Commercial Nuclear Reactor: "Atomic Power at Shippingport" circa 1958 AEC-Westinghouse
First Commercial Nuclear Reactor: "Atomic Power at Shippingport" circa 1958 AEC-Westinghouse
DATE: 2012/09/17::
44
First Commercial Nuclear Reactor   Shipping Port PA
First Commercial Nuclear Reactor Shipping Port PA
DATE: 2014/01/30::
45
The Shining Darkness Cards (Yugioh Collection 54)
The Shining Darkness Cards (Yugioh Collection 54)
DATE: 2014/04/09::
46
Fission cross section for epithemral neutrons inside JSI TRIGA Mark II reactor
Fission cross section for epithemral neutrons inside JSI TRIGA Mark II reactor
DATE: 2013/11/05::
47
Cantor Dust Reflector (Scaling Test)
Cantor Dust Reflector (Scaling Test)
DATE: 2012/04/05::
48
JETBeam BC10  R5
JETBeam BC10 R5
DATE: 2011/03/18::
49
Costco
Costco's 4-AAA 300 lumen flashlight (Duracell)
DATE: 2014/10/01::
50
Fukushima arcing
Fukushima arcing
DATE: 2014/10/05::
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RESULTS [51 .. 101]
From Wikipedia, the free encyclopedia
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A neutron reflector is any material that reflects neutrons. This refers to elastic scattering rather than to a specular reflection. The material may be graphite, beryllium, steel, tungsten carbide, or other materials. A neutron reflector can make an otherwise subcritical mass of fissile material critical, or increase the amount of nuclear fission that a critical or supercritical mass will undergo. An example of this is the Demon Core, a subcritical plutonium pit that went critical in two separate fatal incidents when the pit's surface was momentarily surrounded by too much neutron reflective material.

Nuclear reactors[edit]

In a uranium graphite chain reacting pile, the critical size may be considerably reduced by surrounding the pile with a layer of graphite, since such an envelope reflects many neutrons back into the pile.

To obtain a 30 year life span, the SSTAR nuclear reactor design calls for a moveable neutron reflector to be placed over the column of fuel. The reflector's slow downward travel over the column would cause the fuel to be burned from the top of the column to the bottom.

A reflector made of a light material like graphite or beryllium will also serve as a neutron moderator reducing neutron kinetic energy, while a heavy material like lead or lead-bismuth eutectic will have less effect on neutron velocity.

Nuclear weapons[edit]

A similar envelope can be used to reduce the critical size of a nuclear weapon, but here the envelope has an additional role: its very inertia delays the expansion of the reacting material. For this reason such an envelope is often called a tamper. The weapon tends to fly to bits as the reaction proceeds and this tends to stop the reaction, so the use of a tamper makes for a longer lasting, more energetic, and more efficient explosion. The most effective tamper is the one having the highest density; high tensile strength is unimportant because no material remains intact under the extreme pressures of a nuclear weapon. Coincidentally, high density materials are excellent neutron reflectors. This makes them doubly suitable for nuclear weapons. The first nuclear weapons used heavy uranium or tungsten carbide tamper-reflectors.

On the other hand, a heavy tamper necessitates a larger high explosive implosion system. The primary stage of a modern thermonuclear weapon may use a lightweight beryllium reflector, which is also transparent to X-rays when ionized, allowing the primary's energy output to escape quickly to be used in compressing the secondary stage.

While the effect of a tamper is to increase efficiency, both by reflecting neutrons and by delaying the expansion of the bomb, the effect on the critical mass is not as great. The reason for this is that the process of reflection is time consuming.

See also[edit]

References[edit]

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