Questions tagged [nuclear-engineering]
The study of radiation and radioactive materials and their creation, safety, and applications.
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Why is it impossible for the reactor of the nuclear power plant to turn into an explosive nuclear bomb?
Is it true that both work on the same principle of operation: the interactive fission chain reaction 235U/239Pu and the bombardment of uranium-235 by fast neutrons produce a fission chain reaction ...
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How many more neutrons are flying around in a fast reactor vs thermal reactor?
I'm a bit confused on the number of neutrons in a fast reactor.
So the average neutron in a thermal reactor is 0.05ev and 700kev in a fast reactor. This means fast reactor neutrons are travelling sqrt(...
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Use of Anger logic for sub anode size spatial resolution using pixelated scintillation crystals
Anger logic is widely used as a centroiding formula to spatially locate the scintillation event in multi-anode PMTs (MA-PMT). For pixelated scintillation crystals with pixel sizes smaller than single ...
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What exactly is energy self-shielding in nuclear physics?
I have recently been trying to understand self-shielding, both energy and spatial self-shielding. I am having a particularly hard time understanding energy self shielding. Thus far, everything I’ve ...
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Nuclear Propulsion System
In a fictional sci-fi setting , is it plausible to:
Have a huge nuclear powered aircraft carrier to be propelled by H2-O2 rocket engine (size adjust) where you generate both from sea water on the fly ...
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How much faster does induced fission in a typical reactor occur than spontaneous fission in nature?
I know that the half-life of Uranium-235 is about 704 million years, but...
That includes alpha and beta radiation as well as spontaneous fission, though...
Also, I presume the 'spontaneous fission' ...
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Is special relativity relevant to understand nuclear bombs?
It is often claimed that Special Relativity had a huge impact on humanity because its understand enabled the invention of the nuclear bomb. Often, the formula $E = mc^2$ is displayed in this context, ...
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What is the name of the instrument that separates substances using an electromagnetic field, similar to spectrography
As far as I remember, the elements of the substance are passed across an electromagnetic field in such a way that they seperate as the electromagnetic field alters their trajectory. I also seem to ...
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How will "Fusion Power" deal with it's waste heat?
in application of Fusion power, even if it were doable at present, given the multi-million degree operation, how does such a system dispose of waste heat if plasma is magnetically confined?
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If plutonium-238 (Pu-238) absorbs a neutron, does it become Pu-239?
I am asking this simple question because I am always hearing about how thorium reactors are less perilous to the world because, unlike uranium reactors, they produce some Pu-238, which is not suitable ...
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What would happen if an atomic bomb exploded on a nuclear power plant?
Would the effect be different than if the nuclear power plant were bombeb with traditional explosives?
Would the atomic bomb neutralise any potential radioactive effect of the obliteration of the ...
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Working out radiation rates
Suppose the radiation dose of a CO-$57$ source was measured to be $63$ mR/hour $5$cm away from the source. Is there any way to measure the radiation at the source? ($0$cm from the source). I thought ...
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How photon beam can be attained through Proton Accelerator?
I'm recently had been reading quite a lot about ADS and transmutation possiblity of Proton beam to neutralize nuclear waste. I came across with an Article from Big THINK https://bigthink.com/the-...
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How can I attain deuterons using a proton accelerator?
I'm in high school and I had read in this paper https://cds.cern.ch/record/849079/files/thesis-2005-033.pdf
That deuterons can be better in spallation process. I was curious how we can use the proton ...
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How can I couple MCNP with FLUKA? To attain reactor dynamics and simulate an ADS(Accelerator Driven System) experiment?
I'm new in Particle Physics based Computing. I want to simulate an ADS experiment (Accelerator Driven System) in subcritical fast system. I was advised to simulate the experiment with FLUKA with MCNP ...
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Can Anti-Particle like Anti-Proton give advantage in ADS (Accelerator Driven System) for Neutralizing Nuclear Waste?
I was going through a thesis of Adonai Martinez for "Transmutation of Nuclear Waste in Accelerator-Driven Systems" published in 2004.
I saw he used Proton for ADS but it occured to me that, ...
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What is leftover of MOX fuel after being burned in a fast reactor?
My understanding is that basically the U-238 and P-239 play off each other and it can keep reacting essentially as long as the neutron density is enough. The U-238 that doesn't fission eventually ...
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Tokamak and Lithium "blankets"
I am working on planning out nuclear fusion for a fictional world, and I am wondering if two ideas are able to work together, or if they contradict each other.
So Dueterium-Tritium fusion releases ...
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Will helium produced during a Nuclear fusion go back to Hydrogen?
I don’t know whether I’m right or wrong, but my argument is that, When hydrogen is converted into helium during fusion, a large amount of energy is produced roughly of order of 18Mega eV(At least that’...
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Radiation shield with moving electrons - where would this idea fail?
Disclaimer: I'm a total layman, please go easy on me. :)
On some Youtube video some time ago (yes, sounds promising, but it was a quality video, I swear!) I saw some nuclear physicist talking about ...
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China's "Artificial sun"
So I heard in the radio today about China's "Artificial sun". There is this hype about it having 5x the temperature of the core of the sun.
It is, as I suspected, a fusion reactor. I admit I ...
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Alternatives to Steam Engines [closed]
Since the 18th century, humankind relied on steam engines to convert heat into electricity on mass scale even in fission and fusion (in the future) power plants.
However, this process involves several ...
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How do you contain a nuclear explosion? [closed]
What properties would a material need to contain a nuclear explosion (I'll go with the Tsar Bomba) such that it has no effect on outside conditions. For specificity I'll go with:
Ultimate tensile ...
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Origin of Nuclear fusion energy
What causes the mass of the two reacting nuclei to convert to energy and if it is for a purpose then why is it released. What is the source for this cause (if there)?
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What are the chemical properties of uranium-233 that makes it a more efficient fuel than uranium 235?
i'm trying to find what the best nuclear fuel would be. I've already tried finding this answer online but there's nothing that helps. i would like to find an answer please. btw, by efficient, i mean ...
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Is it possible securely detonate a hydrogen bomb inside a very, very thick iron armor to get the armor only rise its temperature and not break apart? [closed]
Is it possible securely detonate a small hydrogen bomb inside a very, very thick iron armor, preferabely a sphere, to get the armor only rise its temperature and not break apart? Would it be a hazzard ...
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What is the risk of self-detonation or meltdown of unattended nuclear arsenal? [closed]
Assume some missiles or bombs left unattended for at least 1,000 years. Chance of self-detonation? After playing with Powder Toy a bit, started me thinking: if Polonium and Americium are break-down ...
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In a hypothetical neutrinoless beta decay, how the energy spectrum will look like?
If we consider a hypothetical situation in which $\beta^-$ deacay is happening without emitting any anti-neutrino, to be precise, a neutrinoless beta decay is happening. So, in this case, how the ...
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What happens to all the stolen neutrons in nuclear reactor?
I'm reading about chain reactions in pressurized water reactors. All is good and clear. U-235 splits, releases 2 or 3 neutrons, if the reactor is supercritical then reaction will continue. Part of the ...
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How much more efficient is the nuclear fusion reaction of tritium and deuterium compared to two deuterons interacting?
Fusion is all the rage (again) these days, and most sources and popular articles claim that tritium-deuterium is the most 'efficient', with a cross-section of about 5 barns....
But what are the cross ...
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Why is Zirconium neutron transparent while Hafnium is such a neutron absorber?
Out of curiosity I've been researching about Hafnium and Zirconium. I'm curious as to why Hafnium (below Zirconium on the periodic table) is so often used in control rods, while Zirconium is ...
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What happens to a nuclear plant when you stop cooling it?
An IEA report says that many nuclear plants use freshwater for cooling, and that due to climate change, a growing portion of them are going to find themselves in high water stress areas. Does it mean ...
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Are nuclear weapons energy negative?
Not sure if this belongs here, Chemistry, History, or some other Stack Exchange site, but I'll start it here and welcome migration to a different site if appropriate.
In doing some reading on the ...
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Does transmutation of nuclear waste need more energy than it originally produced?
Nuclear transmutation has been proposed as a method to reduce nuclear waste from nuclear power plants:
https://en.wikipedia.org/wiki/Nuclear_transmutation
I recall reading somewhere that this is ...
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Can fusion power production be quickly attenuated/increased, in principle?
Today there was an announcement of a breakthrough in the path toward fusion energy.
This presentation by Michael Shellenberger states that a problem with wind and solar is that, because of ...
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How do nuclear fuel rods get "spent"? Why can't you just throw neutrons at them?
The idea of fuel rods being both "spent" and dangerously radioactive has always seemed to me to be self-contradictory. The typical explanation given is that the human body and environment ...
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Fission Weapon Mechanism and Critical Mass
In the image we see the interior design of the Little Boy atomic bomb dropped on Hiroshima. There are two cylinders composed of uranium, a hollow cylinder at the top which will slide down to merge ...
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Direction of Radioactive Emission
Where does the emission of a radioactive material directed at?
My intuition and background knowledge would firmly say that it is pointing at all directions outward of the atomic nucleus. But let's say ...
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How does light water prevent criticality of natural uranium even as it is outside the zirconium cladding?
The main reason heavy water is used to allow nuclear reactors to operate with nuclear reactor is that they do not absorb neutrons, allowing an increase in neutron temperature that lets the few U-238 ...
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What would happen if I change the polarity of my gas chamber radiation detector?
What would happen if I change my ionization chamber polarity?
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Was it possible for Little Boy to have predetonated and fizzled?
In the Manhattan project they originally planned to use plutonium for their gun-type bomb and gave the design the name "Thin Man". However it was later determined that reactor-bred Pu-239 ...
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What is "plasma discharge"?
I am trying to find the definition of "plasma discharge"? I googled and only found one useful site:https://www.ipp.mpg.de/ippcms/eng/pr/exptypen/tokamak/plasmaentladungen/index
(in magnetic ...
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Which theory can explains or predicts conservation of nucleons?
Number of nucleons are conserved in a nuclear reaction and decays. Is there a theory which predicts that?
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How to mantain plasma current in a tokamak?
I know that a toroidal plasma current is an essential feature on tokamaks as it creates the poloidal magnetic field essential to avoid separation between negative and positive charges.
The current is ...
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Can we affect nuclear warheads with neutrinos?
I heard, that we can either disarm or detonate nuclear warhead if we could target neutrino beam onto it. Is it true? Which reaction it would be? Conversion of neutrons to protons? Or conversion of ...
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How do cycling moltant salt reactors do nuclear fission?
I only have an understand of how PWR's do nuclear fission, looking at the diagram for the salt reactors it's a bit confusing. Where is the fission taking place if the salt is cycling throughout the ...
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Why free neutrons are usually produced in a Nuclear Fission?
The production of neutrons is a feature of fission reaction. Usually 2-3 free neutrons are produced in the fission. Why is that so?
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Does Build up factor actually make it worse to have shielding?
I'm having a little trouble understanding Build up factor in radioactive shielding equations. I learned that the equation for shielding with the Build up factor is:
$$I = I_0 \cdot B e^{-ux}$$
And I ...
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What went wrong with the nuclear boy scouts breeder reactor?
If I recall correctly the Nuclear boy scout tried to build a breeder reactor but the experiment gave him radiation poisoning because the neutron emitter was to emitting to many neutrons.
Does anyone ...
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Why are PWR's being build instead of FBR's or LMFBR's?
Why are PWR's still being built in modern times when we have the option to use designs that allow intake of raw uranium without the need for enrichment and allow for recycling of waste material.
I don'...