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Nuclear reactions
The term "nuclear reaction" may refer either to a change in a nuclide induced by collision with another particle or to a spontaneous change of a nuclide without collision. Natural nuclear reactions occur in the interaction between cosmic rays and matter, and nuclear reactions can be employed artificially to obtain nucl...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Fission barrier
In nuclear physics and nuclear chemistry, the fission barrier is the activation energy required for a nucleus of an atom to undergo fission. This barrier may also be defined as the minimum amount of energy required to deform the nucleus to the point where it is irretrievably committed to the fission process. The energy...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Isospin
In nuclear physics and particle physics, isospin (I) is a quantum number related to the up- and down quark content of the particle. More specifically, isospin symmetry is a subset of the flavour symmetry seen more broadly in the interactions of baryons and mesons. The name of the concept contains the term spin because ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Isospin
Etymologically, the term was derived from isotopic spin, a confusing term to which nuclear physicists prefer isobaric spin, which is more precise in meaning. Before the concept of quarks was introduced, particles that are affected equally by the strong force but had different charges (e.g. protons and neutrons) were co...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Strong nuclear force
In nuclear physics and particle physics, the strong interaction, which is also often called the strong force or strong nuclear force, is a fundamental interaction that confines quarks into proton, neutron, and other hadron particles. The strong interaction also binds neutrons and protons to create atomic nuclei, where ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Strong nuclear force
On a larger scale (of about 1 to 3 fm), it is the force (carried by mesons) that binds protons and neutrons (nucleons) together to form the nucleus of an atom. On the smaller scale (less than about 0.8 fm, the radius of a nucleon), it is the force (carried by gluons) that holds quarks together to form protons, neutrons...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Strong nuclear force
The strong force inherently has such a high strength that hadrons bound by the strong force can produce new massive particles. Thus, if hadrons are struck by high-energy particles, they give rise to new hadrons instead of emitting freely moving radiation (gluons). This property of the strong force is called color confi...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Strong nuclear force
In the context of atomic nuclei, the same strong interaction force (that binds quarks within a nucleon) also binds protons and neutrons together to form a nucleus. In this capacity it is called the nuclear force (or residual strong force). So the residuum from the strong interaction within protons and neutrons also bin...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Strong nuclear force
As such, the residual strong interaction obeys a distance-dependent behavior between nucleons that is quite different from that when it is acting to bind quarks within nucleons. Additionally, distinctions exist in the binding energies of the nuclear force of nuclear fusion vs nuclear fission. Nuclear fusion accounts fo...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Strong nuclear force
Nuclear fission allows for decay of radioactive elements and isotopes, although it is often mediated by the weak interaction. Artificially, the energy associated with the nuclear force is partially released in nuclear power and nuclear weapons, both in uranium or plutonium-based fission weapons and in fusion weapons li...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Nuclear weak force
In nuclear physics and particle physics, the weak interaction, which is also often called the weak force or weak nuclear force, is one of the four known fundamental interactions, with the others being electromagnetism, the strong interaction, and gravitation. It is the mechanism of interaction between subatomic particl...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Effective range
In nuclear physics research, effective range is a physical parameter in the dimension of length to characterize an effective scattering square well potential. It is related to the scattering phase shift by, k cot ⁡ δ = − γ + 1 2 ( γ 2 + k 2 ) r 0 + O ( k 4 r o 3 ) {\displaystyle k\cot \delta =-\gamma +{\frac {1}{2}}\le...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Nuclear spectroscopy
In nuclear physics these methods are used to study properties of the nucleus itself. Methods for studies of the nucleus: Gamma spectroscopy Hypernuclear spectroscopyMethods for condensed matter studies: Nuclear magnetic resonance (NMR) Mössbauer spectroscopy Perturbed angular correlation (PAC, TDPAC, PAC spectroscopy) ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Gamow-Teller transition
In nuclear physics, a beta decay transition is the change in state of an atomic nucleus undergoing beta decay. (β-decay) When undergoing beta decay, a nucleus emits a beta particle and a corresponding neutrino, transforming the original nuclide into one with the same mass, but differing charge. (an isobar) There are se...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Gamow-Teller transition
In a Fermi transition, the spins of the two emitted particles are anti-parallel, for a combined spin S = 0 {\displaystyle S=0} . As a result, the total angular momentum of the nucleus is unchanged by the transition. By contrast, in a Gamow-Teller transition, the spins of the two emitted particles are parallel, with tot...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Magic number (physics)
Atomic nuclei consisting of such a magic number of nucleons have a higher average binding energy per nucleon than one would expect based upon predictions such as the semi-empirical mass formula and are hence more stable against nuclear decay. The unusual stability of isotopes having magic numbers means that transuraniu...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Magic number (physics)
Unlike the magic numbers 2–126, which are realized in spherical nuclei, theoretical calculations predict that nuclei in the island of stability are deformed. Before this was realized, higher magic numbers, such as 184, 258, 350, and 462 (sequence A033547 in the OEIS), were predicted based on simple calculations that as...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Reactivity (nuclear)
In nuclear physics, a nuclear chain reaction occurs when one single nuclear reaction causes an average of one or more subsequent nuclear reactions, thus leading to the possibility of a self-propagating series of these reactions. The specific nuclear reaction may be the fission of heavy isotopes (e.g., uranium-235, 235U...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Stripping reaction (physics)
In nuclear physics, a stripping reaction is a nuclear reaction in which part of the incident nucleus combines with the target nucleus, and the remainder proceeds with most of its original momentum in almost its original direction. This reaction was first described by Stuart Thomas Butler in 1950. Deuteron stripping rea...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Ab initio methods (nuclear physics)
In nuclear physics, ab initio methods seek to describe the atomic nucleus from the bottom up by solving the non-relativistic Schrödinger equation for all constituent nucleons and the forces between them. This is done either exactly for very light nuclei (up to four nucleons) or by employing certain well-controlled appr...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Ab initio methods (nuclear physics)
The strong nuclear force is believed to emerge from the strong interaction described by quantum chromodynamics (QCD), but QCD is non-perturbative in the low-energy regime relevant to nuclear physics. This makes the direct use of QCD for the description of the inter-nucleon interactions very difficult (see lattice QCD),...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Ab initio methods (nuclear physics)
This effective field theory (EFT) includes all interactions compatible with the symmetries of QCD, ordered by the size of their contributions. The degrees of freedom in this theory are nucleons and pions, as opposed to quarks and gluons as in QCD. The effective theory contains parameters called low-energy constants, wh...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Halo nucleus
In nuclear physics, an atomic nucleus is called a halo nucleus or is said to have a nuclear halo when it has a core nucleus surrounded by a "halo" of orbiting protons or neutrons, which makes the radius of the nucleus appreciably larger than that predicted by the liquid drop model. Halo nuclei form at the extreme edges...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Halo nucleus
Its mass radius of 3.16 fm is close to that of 32S or, even more impressively, of 208Pb, both much heavier nuclei.Experimental confirmation of nuclear halos is recent and ongoing. Additional candidates are suspected. Several nuclides including 9B, 13N, and 15N are calculated to have a halo in the excited state but not ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Energy amplifier
In nuclear physics, an energy amplifier is a novel type of nuclear power reactor, a subcritical reactor, in which an energetic particle beam is used to stimulate a reaction, which in turn releases enough energy to power the particle accelerator and leave an energy profit for power generation. The concept has more recen...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Nuclear shell model
In nuclear physics, atomic physics, and nuclear chemistry, the nuclear shell model is a model of the atomic nucleus which uses the Pauli exclusion principle to describe the structure of the nucleus in terms of energy levels. The first shell model was proposed by Dmitri Ivanenko (together with E. Gapon) in 1932. The mod...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Nuclear shell model
Due to some variations in orbital filling, the upper magic numbers are 126 and, speculatively, 184 for neutrons, but only 114 for protons, playing a role in the search for the so-called island of stability. Some semi-magic numbers have been found, notably Z = 40, which gives the nuclear shell filling for the various el...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Atomic Recoil
In nuclear physics, atomic recoil is the result of the interaction of an atom with an energetic elementary particle, when the momentum of the interacting particle is transferred to the atom as a whole without altering non-translational degrees of freedom of the atom. It is a purely quantum phenomenon. Atomic recoil was...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Atomic Recoil
Otto Hahn reworked, explained and demonstrated it in 1908/09. The physicist Walther Gerlach described radioactive recoil as "a profoundly significant discovery in physics with far-reaching consequences".If the transferred momentum of atomic recoil is enough to disrupt the crystal lattice of the material, a vacancy defe...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Bound-state β− decay
In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which an atomic nucleus emits a beta particle (fast energetic electron or positron), transforming into an isobar of that nuclide. For example, beta decay of a neutron transforms it into a proton by the emission of an electron accompanied by an a...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Bound-state β− decay
The probability of a nuclide decaying due to beta and other forms of decay is determined by its nuclear binding energy. The binding energies of all existing nuclides form what is called the nuclear band or valley of stability. For either electron or positron emission to be energetically possible, the energy release (se...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Bound-state β− decay
Beta decay is a consequence of the weak force, which is characterized by relatively lengthy decay times. Nucleons are composed of up quarks and down quarks, and the weak force allows a quark to change its flavour by emission of a W boson leading to creation of an electron/antineutrino or positron/neutrino pair. For exa...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Hyperdeformation
In nuclear physics, hyperdeformation is theoretically predicted states of an atomic nucleus with extremely elongated shape and very high angular momentum. Less elongated states, superdeformation, have been well observed, but the experimental evidence for hyperdeformation is more limited. Hyperdeformed states correspond...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Hyperdeformation
They would be caused by a third minimum in the potential energy surface, the second causing superdeformation and the first minimum being normal deformation. Hyperdeformation is predicted to be found in 107Cd. == References ==
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Odd–odd nuclei
In nuclear physics, properties of a nucleus depend on evenness or oddness of its atomic number (proton number) Z, neutron number N and, consequently, of their sum, the mass number A. Most importantly, oddness of both Z and N tends to lower the nuclear binding energy, making odd nuclei generally less stable. This effect...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Odd–odd nuclei
The neutron–proton ratio is not the only factor affecting nuclear stability. Adding neutrons to isotopes can vary their nuclear spins and nuclear shapes, causing differences in neutron capture cross sections and gamma spectroscopy and nuclear magnetic resonance properties. If too many or too few neutrons are present wi...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Empirical singular values distribution
In nuclear physics, random matrices were introduced by Eugene Wigner to model the nuclei of heavy atoms. Wigner postulated that the spacings between the lines in the spectrum of a heavy atom nucleus should resemble the spacings between the eigenvalues of a random matrix, and should depend only on the symmetry class of ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Resonance escape probability
In nuclear physics, resonance escape probability p {\displaystyle p} is the probability that a neutron will slow down from fission energy to thermal energies without being captured by a nuclear resonance. A resonance absorption of a neutron in a nucleus does not produce nuclear fission. The probability of resonance abs...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Resonance escape probability
These energies depend on the properties of heavy nuclei. Resonance escape probability is highly determined by the heterogeneous geometry of a reactor, because fast neutrons resulting from fission can leave the fuel and slow to thermal energies in a moderator, skipping over resonance energies before reentering the fuel....
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Separation energy
In nuclear physics, separation energy is the energy needed to remove one nucleon (or other specified particle or particles) from an atomic nucleus. The separation energy is different for each nuclide and particle to be removed. Values are stated as "neutron separation energy", "two-neutron separation energy", "proton s...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Separation energy
The energy can be added to the nucleus by an incident high-energy gamma ray. If the energy of the incident photon exceeds the separation energy, a photodisintegration might occur. Energy in excess of the threshold value becomes kinetic energy of the ejected particle. By contrast, nuclear binding energy is the energy ne...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Bateman equation
In nuclear physics, the Bateman equation is a mathematical model describing abundances and activities in a decay chain as a function of time, based on the decay rates and initial abundances. The model was formulated by Ernest Rutherford in 1905 and the analytical solution was provided by Harry Bateman in 1910.If, at ti...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Geiger–Nuttall law
In nuclear physics, the Geiger–Nuttall law or Geiger–Nuttall rule relates the decay constant of a radioactive isotope with the energy of the alpha particles emitted. Roughly speaking, it states that short-lived isotopes emit more energetic alpha particles than long-lived ones. The relationship also shows that half-live...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Geiger–Nuttall law
In practice, this means that alpha particles from all alpha-emitting isotopes across many orders of magnitude of difference in half-life, all nevertheless have about the same decay energy. Formulated in 1911 by Hans Geiger and John Mitchell Nuttall as a relation between the decay constant and the range of alpha particl...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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S-factor
In nuclear physics, the astrophysical S-factor S(E) is a rescaling of a nuclear reaction's total cross section σ(E) to account for the Coulomb repulsion between the charged reactants. It determines the rates of nuclear fusion reactions that occur in the cores of stars.
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Chiral model
In nuclear physics, the chiral model, introduced by Feza Gürsey in 1960, is a phenomenological model describing effective interactions of mesons in the chiral limit (where the masses of the quarks go to zero), but without necessarily mentioning quarks at all. It is a nonlinear sigma model with the principal homogeneous...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Neutron cross-section
In nuclear physics, the concept of a neutron cross section is used to express the likelihood of interaction between an incident neutron and a target nucleus. The neutron cross section σ can be defined as the area in cm2 for which the number of neutron-nuclei reactions taking place is equal to the product of the number ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Neutron cross-section
The larger the neutron cross section, the more likely a neutron will react with the nucleus. An isotope (or nuclide) can be classified according to its neutron cross section and how it reacts to an incident neutron. Nuclides that tend to absorb a neutron and either decay or keep the neutron in its nucleus are neutron a...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Internal conversion coefficient
In nuclear physics, the internal conversion coefficient describes the rate of internal conversion. The internal conversion coefficient may be empirically determined by the following formula: There is no valid formulation for an equivalent concept for E0 (electric monopole) nuclear transitions. There are theoretical cal...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Internal conversion coefficient
Their accuracy is not generally under dispute, but since the quantum mechanical models they depend on only take into account electromagnetic interactions between the nucleus and electrons, there may be unforeseen effects. Internal conversion coefficients can be looked up from tables, but this is time-consuming. Compute...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Internal conversion coefficient
Theoretical calculations of interest are the Rösel, Hager-Seltzer, and the Band, superseded by the Band-Raman calculation called BrIcc. The Hager-Seltzer calculations omit the M and higher-energy shells on the grounds (usually valid) that those orbitals have little electron density at the nucleus and can be neglected. ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Island of stability
While these effects are expected to be greatest near atomic number Z = 114 and N = 184, the region of increased stability is expected to encompass several neighboring elements, and there may also be additional islands of stability around heavier nuclei that are doubly magic (having magic numbers of both protons and neu...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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8
In nuclear physics, the second magic number. In particle physics, the eightfold way is used to classify sub-atomic particles. In statistical mechanics, the eight-vertex model has 8 possible configurations of arrows at each vertex.
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Liquid drop model
In nuclear physics, the semi-empirical mass formula (SEMF) (sometimes also called the Weizsäcker formula, Bethe–Weizsäcker formula, or Bethe–Weizsäcker mass formula to distinguish it from the Bethe–Weizsäcker process) is used to approximate the mass of an atomic nucleus from its number of protons and neutrons. As the n...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Liquid drop model
It was first formulated in 1935 by German physicist Carl Friedrich von Weizsäcker, and although refinements have been made to the coefficients over the years, the structure of the formula remains the same today. The formula gives a good approximation for atomic masses and thereby other effects. However, it fails to exp...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Symmetry energy
In nuclear physics, the symmetry energy reflects the variation of the binding energy of the nucleons in the nuclear matter depending on its neutron to proton ratio as a function of baryon density. Symmetry energy is an important parameter in the equation of state describing the nuclear structure of heavy nuclei and neu...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Valley of stability
In nuclear physics, the valley of stability (also called the belt of stability, nuclear valley, energy valley, or beta stability valley) is a characterization of the stability of nuclides to radioactivity based on their binding energy. Nuclides are composed of protons and neutrons. The shape of the valley refers to the...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Valley of stability
Regions of instability within the valley at high atomic number also include radioactive decay by alpha radiation or spontaneous fission. The shape of the valley is roughly an elongated paraboloid corresponding to the nuclide binding energies as a function of neutron and atomic numbers.The nuclides within the valley of ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Polyadenylation
In nuclear polyadenylation, a poly(A) tail is added to an RNA at the end of transcription. On mRNAs, the poly(A) tail protects the mRNA molecule from enzymatic degradation in the cytoplasm and aids in transcription termination, export of the mRNA from the nucleus, and translation. Almost all eukaryotic mRNAs are polyad...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Polyadenylation
These are the only mRNAs in eukaryotes that lack a poly(A) tail, ending instead in a stem-loop structure followed by a purine-rich sequence, termed histone downstream element, that directs where the RNA is cut so that the 3′ end of the histone mRNA is formed.Many eukaryotic non-coding RNAs are always polyadenylated at ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Burnup
In nuclear power technology, burnup (also known as fuel utilization) is a measure of how much energy is extracted from a primary nuclear fuel source. It is measured as the fraction of fuel atoms that underwent fission in %FIMA (fissions per initial metal atom) or %FIFA (fissions per initial fissile atom) as well as, pr...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Per cent mille
In nuclear reactor engineering, a per cent mille is equal to one-thousandth of a percent of the reactivity, denoted by Greek lowercase letter rho. Reactivity is a dimensionless unit representing a departure from criticality, calculated by: ρ = ( k eff − 1 ) / k eff {\displaystyle \rho =(k_{\text{eff}}-1)/k_{\text{eff}}...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Exponentially decaying
In nuclear science and pharmacokinetics, the agent of interest might be situated in a decay chain, where the accumulation is governed by exponential decay of a source agent, while the agent of interest itself decays by means of an exponential process. These systems are solved using the Bateman equation. In the pharmaco...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Actinium series
In nuclear science, the decay chain refers to a series of radioactive decays of different radioactive decay products as a sequential series of transformations. It is also known as a "radioactive cascade". The typical radioisotope does not decay directly to a stable state, but rather it decays to another radioisotope.
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Actinium series
Thus there is usually a series of decays until the atom has become a stable isotope, meaning that the nucleus of the atom has reached a stable state. Decay stages are referred to by their relationship to previous or subsequent stages. A parent isotope is one that undergoes decay to form a daughter isotope.
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Actinium series
One example of this is uranium (atomic number 92) decaying into thorium (atomic number 90). The daughter isotope may be stable or it may decay to form a daughter isotope of its own. The daughter of a daughter isotope is sometimes called a granddaughter isotope.
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Actinium series
Note that the parent isotope becomes the daughter isotope, unlike in the case of a biological parent and daughter. The time it takes for a single parent atom to decay to an atom of its daughter isotope can vary widely, not only between different parent-daughter pairs, but also randomly between identical pairings of par...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Actinium series
One of the properties of an isotope is its half-life, the time by which half of an initial number of identical parent radioisotopes can be expected statistically to have decayed to their daughters, which is inversely related to λ. Half-lives have been determined in laboratories for many radioisotopes (or radionuclides)...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Actinium series
If and when equilibrium is achieved, each successive daughter isotope is present in direct proportion to its half-life; but since its activity is inversely proportional to its half-life, each nuclide in the decay chain contributes as many individual transformations as the head of the chain, though not the same energy. ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Hyperfine coupling
In nuclear spectroscopy methods, the nucleus is used to probe the local structure in materials. The methods mainly base on hyperfine interactions with the surrounding atoms and ions. Important methods are nuclear magnetic resonance, Mössbauer spectroscopy, and perturbed angular correlation.
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Preemptive nuclear strike
In nuclear strategy, a first strike or preemptive strike is a preemptive surprise attack employing overwhelming force. First strike capability is a country's ability to defeat another nuclear power by destroying its arsenal to the point where the attacking country can survive the weakened retaliation while the opposing...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Minimum deterrence
In nuclear strategy, minimal deterrence, also known as minimum deterrence and finite deterrence, is an application of deterrence theory in which a state possesses no more nuclear weapons than is necessary to deter an adversary from attacking. Pure minimal deterrence is a doctrine of no first use, holding that the only ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Minimum deterrence
While the United States and the Soviet Union each developed robust first- and second-strike capabilities during the Cold War, the People's Republic of China pursued a doctrine of minimal nuclear deterrence. Assuming that decision-makers make cost-benefit analyses when deciding to use force, China's doctrine calls for a...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Minimum deterrence
Decision-makers often feel pressured to expand their arsenals when they perceive them to be vulnerable to an adversary's first strike, especially when both sides seek to achieve the advantage. Eliminating this perceived vulnerability reduces the incentive to produce more and advanced weapons. For example, the United St...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Minimum deterrence
In response to this, China continues to modernize its nuclear forces because its leaders are concerned about the survivability of their arsenal in the face of the United States’ advances in strategic reconnaissance, precision strike, and missile defense.One disadvantage of minimal deterrence is that it requires an accu...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Gamow-Teller transition
In nuclear transitions governed by strong and electromagnetic interactions (which are invariant under parity), the physical laws would be the same if the interaction was reflected in a mirror. Hence the sum of a vector and a pseudovector is not meaningful. However, the weak force, which governs beta decay and the corre...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Gamow-Teller transition
The spin of the parent nucleus can either remain unchanged or change by ±1. However, unlike the Fermi transition, transitions from spin 0 to spin 0 are excluded. In terms of total nuclear angular momentum, the Gamow–Teller transition ( I i → I f {\displaystyle I_{i}\rightarrow I_{f}} ) is Δ I = I f − I i = { 0 I i = I ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Nuclear MASINT
In nuclear war, after nuclear weapons accidents, and with the contemporary threat of "dirty bomb" radiological warfare, measuring the intensity of high-intensity ionizing radiation, and the cumulative dose received by personnel, is critical safety information. The survey function measures the type of active ionizing ra...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Quantum numbers
In nuclei, the entire assembly of protons and neutrons (nucleons) has a resultant angular momentum due to the angular momenta of each nucleon, usually denoted I. If the total angular momentum of a neutron is jn = ℓ + s and for a proton is jp = ℓ + s (where s for protons and neutrons happens to be 1/2 again (see note)),...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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RNA origami
In nucleic acids nanotechnology, artificial nucleic acids are designed to form molecular components that can self-assemble into stable structures for use ranging from targeted drug delivery to programmable biomaterials. DNA nanotechnology uses DNA motifs to build target shapes and arrangements. It has been used in a va...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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RNA origami
RNA nanotechnology combines the simplistic design and manipulation characteristic of DNA, with the additional flexibility in structure and diversity in function similar to that of proteins. RNA's versatility in structure and function, favorable in vivo attributes, and bottom-up self-assembly is an ideal avenue for deve...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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RNA origami
The first work in RNA origami appeared in Science, published by Ebbe S. Andersen of Aarhus University. Researchers at Aarhus University used various 3D models and computer software to design individual RNA origami.
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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RNA origami
Once encoded as a synthetic DNA gene, adding RNA polymerase resulted in the formation of RNA origami. Observation of RNA was primarily done through atomic force microscopy, a technique that allows researchers to look at molecules a thousand times closer than would normally be possible with a conventional light microsco...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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RNA origami
They were able to form honeycomb shapes, but determined other shapes are also possible. Cody Geary, a scholar in the field of RNA origami, described the uniqueness of the method of RNA origami. He stated that its folding recipe is encoded in the molecule itself, and determine by its sequence. The sequence gives the RNA...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Nitro compounds
In nucleophilic aliphatic substitution, sodium nitrite (NaNO2) replaces an alkyl halide. In the so-called Ter Meer reaction (1876) named after Edmund ter Meer, the reactant is a 1,1-halonitroalkane: The reaction mechanism is proposed in which in the first slow step a proton is abstracted from nitroalkane 1 to a carbani...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Trifluoromethylation
The challenges associated with observation of CF3 anion are alluded to its strong basic nature and its tendency to form pentacoordinated silicon species, such as − or −. The reactivity of fluoroform in combination with a strong base such as t-BuOK with carbonyl compounds in DMF is an example. Here CF3− and DMF form an ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Nucleotide sugars metabolism
In nucleotide sugar metabolism a group of biochemicals known as nucleotide sugars act as donors for sugar residues in the glycosylation reactions that produce polysaccharides. They are substrates for glycosyltransferases. The nucleotide sugars are also intermediates in nucleotide sugar interconversions that produce som...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Nucleotide sugars metabolism
These glycoconjugates are virulence factors and components of the fungal and bacterial cell wall. These pathways are also studied in plants, but here the enzymes involved are less well understood. == References ==
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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P value
In null-hypothesis significance testing, the p-value is the probability of obtaining test results at least as extreme as the result actually observed, under the assumption that the null hypothesis is correct. A very small p-value means that such an extreme observed outcome would be very unlikely under the null hypothes...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Ideal number
In number theory an ideal number is an algebraic integer which represents an ideal in the ring of integers of a number field; the idea was developed by Ernst Kummer, and led to Richard Dedekind's definition of ideals for rings. An ideal in the ring of integers of an algebraic number field is principal if it consists of...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Modular curves
In number theory and algebraic geometry, a modular curve Y(Γ) is a Riemann surface, or the corresponding algebraic curve, constructed as a quotient of the complex upper half-plane H by the action of a congruence subgroup Γ of the modular group of integral 2×2 matrices SL(2, Z). The term modular curve can also be used t...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Rational point
In number theory and algebraic geometry, a rational point of an algebraic variety is a point whose coordinates belong to a given field. If the field is not mentioned, the field of rational numbers is generally understood. If the field is the field of real numbers, a rational point is more commonly called a real point. ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Tate conjecture
In number theory and algebraic geometry, the Tate conjecture is a 1963 conjecture of John Tate that would describe the algebraic cycles on a variety in terms of a more computable invariant, the Galois representation on étale cohomology. The conjecture is a central problem in the theory of algebraic cycles. It can be co...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Tate twist
In number theory and algebraic geometry, the Tate twist, named after John Tate, is an operation on Galois modules. For example, if K is a field, GK is its absolute Galois group, and ρ: GK → AutQp(V) is a representation of GK on a finite-dimensional vector space V over the field Qp of p-adic numbers, then the Tate twist...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Freeman Dyson
In number theory and combinatorics rank of a partition of a positive integer is a certain integer associated with the partition. Dyson introduced the concept in a paper published in the journal Eureka. It was presented in the context of a study of certain congruence properties of the partition function discovered by th...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Multipartition
In number theory and combinatorics, a multipartition of a positive integer n is a way of writing n as a sum, each element of which is in turn a partition. The concept is also found in the theory of Lie algebras.
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Ferrers diagram
In number theory and combinatorics, a partition of a non-negative integer n, also called an integer partition, is a way of writing n as a sum of positive integers. Two sums that differ only in the order of their summands are considered the same partition. (If order matters, the sum becomes a composition.) For example, ...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Ferrers diagram
The order-dependent composition 1 + 3 is the same partition as 3 + 1, and the two distinct compositions 1 + 2 + 1 and 1 + 1 + 2 represent the same partition as 2 + 1 + 1. An individual summand in a partition is called a part. The number of partitions of n is given by the partition function p(n).
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Partition problem
In number theory and computer science, the partition problem, or number partitioning, is the task of deciding whether a given multiset S of positive integers can be partitioned into two subsets S1 and S2 such that the sum of the numbers in S1 equals the sum of the numbers in S2. Although the partition problem is NP-com...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus
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Partition problem
In multiway number partitioning, there is an integer parameter k, and the goal is to decide whether S can be partitioned into k subsets of equal sum (the partition problem is the special case in which k = 2). However, it is quite different than the 3-partition problem: in that problem, the number of subsets is not fixe...
https://www.kaggle.com/datasets/conjuring92/wiki-stem-corpus