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2
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3
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Feed the beast- Mindcrack: Ep. 118 -Neutron Reflectors Are Breaking Bad
DATE: 2014/01/19::
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Rarpack Episode 12: I fixed the reflectors!
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DATE: 2012/09/29::
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Idea: Complementary Transmutation Nuclear Reactor
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ReactorCraft Tutorial #6 - 6 Core Fission Reactor
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25
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ThruNite Neutron 1A review - Short Version
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32
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DATE: 2013/06/18::
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Review of the ThruNite Neutron 2C
Review of the ThruNite Neutron 2C
DATE: 2011/02/19::
34
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Thrunite Catapult V3 XML Led (Smooth Reflector)
DATE: 2011/04/05::
35
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ThruNite Neutron Flood EDC Cree XM-L LED Flashlight
DATE: 2011/02/06::
36
Half Moon in a 4.5 Inch Reflector Telescope
Half Moon in a 4.5 Inch Reflector Telescope
DATE: 2011/04/13::
37
Astronomy - Cleaning a Telescope Mirror Safely
Astronomy - Cleaning a Telescope Mirror Safely
DATE: 2010/09/07::
38
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Neutron v2 style with precession - Down/Down/Up
DATE: 2013/06/13::
39
NEUTRON FLUX MONITORING SYSTEM NFMS-IP
NEUTRON FLUX MONITORING SYSTEM NFMS-IP
DATE: 2010/10/13::
40
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Porcelana - Viaje al Sur
DATE: 2010/09/24::
41
How To Make a DIY SteadyCam Tutorial By [ Neutron Studios]
How To Make a DIY SteadyCam Tutorial By [ Neutron Studios]
DATE: 2012/05/26::
42
Newtonian Inspiral of 2 Neutron Stars Simulation
Newtonian Inspiral of 2 Neutron Stars Simulation
DATE: 2007/08/08::
43
Сборка Майнкрафт 18
Сборка Майнкрафт 18
DATE: 2015/05/10::
44
The Shining Darkness Cards (Yugioh Collection 54)
The Shining Darkness Cards (Yugioh Collection 54)
DATE: 2014/04/09::
45
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::
46
First Commercial Nuclear Reactor   Shipping Port PA
First Commercial Nuclear Reactor Shipping Port PA
DATE: 2014/01/30::
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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::
48
ThruNite T30S V2 Flashlight, A Practical Tactical Light
ThruNite T30S V2 Flashlight, A Practical Tactical Light
DATE: 2015/02/01::
49
Cantor Dust Reflector (Scaling Test)
Cantor Dust Reflector (Scaling Test)
DATE: 2012/04/05::
50
How to Assemble The Orion SpaceProbe 130ST EQ - Part 2
How to Assemble The Orion SpaceProbe 130ST EQ - Part 2
DATE: 2012/04/04::
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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. Such an effect was exhibited twice in accidents involving 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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