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Novosil is a stimulant of plant immunity and growth. It is also used in the fight against plant viruses. The product was developed by the Institute together with the Institute of Cytology and Genetics in 1992. It is used in various regions of Russia, as well as in Kazakhstan, Belarus, Ukraine and Georgia. | Wikipedia - Vorozhtsov Novosibirsk Institute of Organic Chemistry | null | null | null |
Acrylate-siloxane hybrid monomer is a material with the addition of silicon. It can be used to create microcircuits. == References == | Wikipedia - Vorozhtsov Novosibirsk Institute of Organic Chemistry | null | null | null |
Now assume G {\displaystyle G} is a topological group and X {\displaystyle X} a topological space on which it acts by homeomorphisms. The action is said to be continuous if the map G × X → X {\displaystyle G\times X\to X} is continuous for the product topology. The action is said to be proper if the map G × X → X × X {... | Wikipedia - Faithful group action | null | null | null |
In particular, this is equivalent to proper discontinuity when G {\displaystyle G} is a discrete group. It is said to be locally free if there exists a neighbourhood U {\displaystyle U} of e G {\displaystyle e_{G}} such that g ⋅ x ≠ x {\displaystyle g\cdot x\not =x} for all x ∈ X {\displaystyle x\in X} and g ∈ U ∖ { e ... | Wikipedia - Faithful group action | null | null | null |
Now consider the case of a chain of two decays: one nuclide A decaying into another B by one process, then B decaying into another C by a second process, i.e. A → B → C. The previous equation cannot be applied to the decay chain, but can be generalized as follows. Since A decays into B, then B decays into C, the activi... | Wikipedia - Nuclear decay | null | null | null |
{\displaystyle {\frac {\mathrm {d} N_{B}}{\mathrm {d} t}}=-\lambda _{B}N_{B}+\lambda _{A}N_{A}.} The rate of change of NB, that is dNB/dt, is related to the changes in the amounts of A and B, NB can increase as B is produced from A and decrease as B produces C. Re-writing using the previous results: The subscripts simp... | Wikipedia - Nuclear decay | null | null | null |
In the case where B is a stable nuclide (λB = 0), this equation reduces to the previous solution: lim λ B → 0 = N A 0 λ A 0 − λ A ( e − λ A t − 1 ) = N A 0 ( 1 − e − λ A t ) , {\displaystyle \lim _{\lambda _{B}\rightarrow 0}\left={\frac {N_{A0}\lambda _{A}}{0-\lambda _{A}}}\left(e^{-\lambda _{A}t}-1\right)=N_{A0}\left... | Wikipedia - Nuclear decay | null | null | null |
Now define an action of so(3,1) on the σμν, and the linear subspace Vσ ⊂ Cl4(C) they span in Cl4(C) ≈ MnC, given by The last equality in (C4), which follows from (C2) and the property (D1) of the gamma matrices, shows that the σμν constitute a representation of so(3,1) since the commutation relations in (C4) are exactl... | Wikipedia - Bispinor | null | null | null |
Now expand the situation to have one sentient being observing the device. Now, they too enter the indefinite state. Their eyes, body, and brain are seeing both spins at the same time. The mind however, stochastically chooses one of the directions, and that is what the mind sees. | Wikipedia - Many-minds interpretation | null | null | null |
When this observer views the second detector, their body will see both results. Their mind will choose the result that agrees with the first detector, and the observer will see the expected results. However, the observer's mind seeing one result does not directly affect the distant state – there is just no wave functio... | Wikipedia - Many-minds interpretation | null | null | null |
Now more than ever, visibility and optimization of in-ground assets are vital to our industry. The PODS organization maintains 4 strategic goals: | Wikipedia - Pipeline Open Data Standard | null | null | null |
Now that the deduction system of HM is at hand, one could present an algorithm and validate it with respect to the rules. Alternatively, it might be possible to derive it by taking a closer look on how the rules interact and proof are formed. This is done in the remainder of this article focusing on the possible decisi... | Wikipedia - Hindley–Milner type system | null | null | null |
Now that the shape of the proof is known, one is already close to formulating a type inference algorithm. Because any proof for a given expression must have the same shape, one can assume the monotypes in the proof's judgements to be undetermined and consider how to determine them. Here, the substitution (specialisatio... | Wikipedia - Hindley-Milner type inference | null | null | null |
And in fact, one can, as looking at the rules of ⊢ S {\displaystyle \vdash _{S}} suggests:: The critical choice is τ. At this point, nothing is known about τ, so one can only assume the most general type, which is ∀ α . α {\displaystyle \forall \alpha .\alpha } . The plan is to specialize the type if it should become n... | Wikipedia - Hindley-Milner type inference | null | null | null |
Unfortunately, a polytype is not permitted in this place, so some α has to do for the moment. To avoid unwanted captures, a type variable not yet in the proof is a safe choice. Additionally, one has to keep in mind that this monotype is not yet fixed, but might be further refined. | Wikipedia - Hindley-Milner type inference | null | null | null |
: The choice is how to refine σ. Because any choice of a type τ here depends on the usage of the variable, which is not locally known, the safest bet is the most general one. Using the same method as above one can instantiate all quantified variables in σ with fresh monotype variables, again keeping them open to furthe... | Wikipedia - Hindley-Milner type inference | null | null | null |
Done. : Only the application rule might force a refinement to the variables "opened" so far, as required by both premises. | Wikipedia - Hindley-Milner type inference | null | null | null |
The first premise forces the outcome of the inference to be of the form τ → τ ′ {\displaystyle \tau \rightarrow \tau '} . If it is, then fine. One can later pick its τ' for the result. | Wikipedia - Hindley-Milner type inference | null | null | null |
If not, it might be an open variable. Then this can be refined to the required form with two new variables as before. Otherwise, the type checking fails because the first premise inferred a type which is not and cannot be made into a function type. | Wikipedia - Hindley-Milner type inference | null | null | null |
The second premise requires that the inferred type is equal to τ of the first premise. Now there are two possibly different types, perhaps with open type variables, at hand to compare and to make equal if it is possible. If it is, a refinement is found, and if not, a type error is detected again. | Wikipedia - Hindley-Milner type inference | null | null | null |
An effective method is known to "make two terms equal" by substitution, Robinson's Unification in combination with the so-called Union-Find algorithm.To briefly summarize the union-find algorithm, given the set of all types in a proof, it allows one to group them together into equivalence classes by means of a union pr... | Wikipedia - Hindley-Milner type inference | null | null | null |
Assuming an implementation of union-find at hand, one can formulate the unification of two monotypes as follows: unify(ta, tb): ta = find(ta) tb = find(tb) if both ta,tb are terms of the form D p1..pn with identical D,n then unify(ta, tb) for each corresponding ith parameter else if at least one of ta,tb is a type vari... | Wikipedia - Hindley-Milner type inference | null | null | null |
Now that we have all the terminology we need, we can make simple connections between various structures: Complex exponentiation forms an external monoid ( C , ↑ ) {\displaystyle (\mathbb {C} ,\uparrow )} over the abelian group ( C , ⋅ ) {\displaystyle (\mathbb {C} ,\cdot )} . Prime factorization forests form an externa... | Wikipedia - External (mathematics) | null | null | null |
Now we formalize some definitions that naturally arise from considering our problems. | Wikipedia - Distance geometry problem | null | null | null |
Now we have come to the interesting part where Alice, Bob, and Carol decided to adopt a quantum strategy. The three of them now share a tripartite entangled state | ψ ⟩ = 1 2 ( | 000 ⟩ + | 111 ⟩ ) {\textstyle |{\psi }\rangle ={\frac {1}{\sqrt {2}}}(|000\rangle +|111\rangle )} , known as the GHZ state. If question 0 is ... | Wikipedia - Quantum pseudo-telepathy | null | null | null |
Now, consider the case where one of the participants of the protocol (say Bob) is acting as a malicious user by trying to obtain the secret without the other participants being aware. Analyzing the possibilities, one learns that choosing the proper order in which Bob and Charlie release their measurement bases and resu... | Wikipedia - Quantum secret sharing | null | null | null |
Receiver 2 releases measurement basis. Receiver 1 releases measurement basis.This ordering prevents receiver 2 from knowing which basis to share for tricking the other participants because receiver 2 does not yet know what basis receiver 1 is going to announce was used. | Wikipedia - Quantum secret sharing | null | null | null |
Similarly, since receiver 1 must release their results first, they cannot control if the measurements should be correlated or anticorrelated for the valid combination of bases used. In this way, acting dishonestly will introduce errors in the eavesdropper testing phase whether the dishonest participant is receiver 1 or... | Wikipedia - Quantum secret sharing | null | null | null |
Now, fix a basepoint b on the Riemann sphere away from the poles. Analytic continuation of a fundamental solution Y 1 {\displaystyle Y_{1}} around any pole λi and back to the basepoint will produce a new solution Y 2 {\displaystyle Y_{2}} defined near b. The new and old solutions are linked by the monodromy matrix Mi a... | Wikipedia - Isomonodromic deformations | null | null | null |
One therefore has the Riemann–Hilbert homomorphism from the fundamental group of the punctured sphere to the monodromy representation: π 1 ( C P 1 − { λ 1 , … , λ n } ) → G L ( n , C ) . {\displaystyle \pi _{1}\left(\mathbb {CP} ^{1}-\{\lambda _{1},\dots ,\lambda _{n}\}\right)\to \mathrm {GL} (n,\mathbb {C} ).} A chang... | Wikipedia - Isomonodromic deformations | null | null | null |
Now, given a manifold M of dimension n = p + q {\displaystyle n=p+q} and an embedding ϕ: S p × D q → M {\displaystyle \phi \colon S^{p}\times D^{q}\to M} , define another n-dimensional manifold M ′ {\displaystyle M'} to be M ′ := ( M ∖ int ( im ( ϕ ) ) ) ∪ ϕ | S p × S q − 1 ( D p + 1 × S q − 1 ) . {\displaystyle M'... | Wikipedia - Algebraic surgery theory | null | null | null |
{\displaystyle \phi \left(\partial \left(S^{p}\times D^{q}\right)\right)=\phi \left(S^{p}\times S^{q-1}\right).} One says that the manifold M′ is produced by a surgery cutting out S p × D q {\displaystyle S^{p}\times D^{q}} and gluing in D p + 1 × S q − 1 {\displaystyle D^{p+1}\times S^{q-1}} , or by a p-surgery if one... | Wikipedia - Algebraic surgery theory | null | null | null |
Now, imagine that Alice and Bob share the two-qubit entangled state: | Φ ⟩ = 1 2 ( | 00 ⟩ + | 11 ⟩ ) {\textstyle |\Phi \rangle ={\frac {1}{\sqrt {2}}}(|00\rangle +|11\rangle )} , commonly referred to as an EPR pair. Alice and Bob will use this entangled pair in their strategy as described below. The optimality of this ... | Wikipedia - CHSH inequality | null | null | null |
She will then label the two possible outputs resulting from each measurement choice as a = 0 {\displaystyle a=0} if the first state in the measurement basis is observed, and a = 1 {\displaystyle a=1} otherwise. Bob also uses the bit y {\displaystyle y} received from Charlie to decide which measurement to perform: if y ... | Wikipedia - CHSH inequality | null | null | null |
We analyze the case where x = y = 0 {\displaystyle x=y=0} here: In this case the winning response pairs are a = b = 0 {\displaystyle a=b=0} and a = b = 1 {\displaystyle a=b=1} . On input x = y = 0 {\displaystyle x=y=0} , we know that Alice will measure in the basis | 0 ⟩ , | 1 ⟩ {\displaystyle |0\rangle ,|1\rangle } , ... | Wikipedia - CHSH inequality | null | null | null |
Similarly, the probability that they both output 1 is exactly | ( ⟨ 1 | ⊗ ⟨ a 1 | ) | Φ ⟩ | 2 = 1 2 cos 2 ( π 8 ) {\textstyle |(\langle 1|\otimes \langle a_{1}|)|\Phi \rangle |^{2}={\frac {1}{2}}\cos ^{2}\left({\frac {\pi }{8}}\right)} . So the probability that either of these successful outcomes happens is cos 2 (... | Wikipedia - CHSH inequality | null | null | null |
Nowadays it is possible to solve the classical Streeter–Phelps equation numerically by use of computers. The differential equations are solved by integration. | Wikipedia - Streeter-Phelps equation | null | null | null |
Nowadays many therapists work with resistance as a way to understand the client better. They emphasize the importance to work with the resistance and not against it. This is because working against the resistance of a client can result in a counterproductive relationship with the therapist; the more attention is drawn ... | Wikipedia - Psychological resistance | null | null | null |
The feelings the client evokes in the therapist with his/her resistance will give you a hint what the resistance is about. For example, a very directive client can make the therapist feel very passive. When the therapist pays attention to their passive feelings, it can make him/her understand this behavior of the clien... | Wikipedia - Psychological resistance | null | null | null |
It can also be useful to identify resistance with the client. This can not only work towards addressing the issue but can also allow the client to think about and discuss their resistance and the cognitive processes that underlie it. In this way, the client takes an active involvement in their therapy, which may reduce... | Wikipedia - Psychological resistance | null | null | null |
It also helps the client's ability to identify their resistance in the future and respond to it. Relevant to the question of treatment planning are research studies that have looked at resistance traits as indicators and contra-indicators for different types of interventions. | Wikipedia - Psychological resistance | null | null | null |
Beutler, Moleiro, and Talebi reviewed 20 studies that inspected the differential effects of therapist directiveness as moderated by client resistance and found that 80% (n=16) of the studies demonstrated that directive interventions were most productive among clients who had relatively low levels of state or trait-like... | Wikipedia - Psychological resistance | null | null | null |
Nowadays the words 'semialgebraic geometry' and 'real algebraic geometry' are used as synonyms, because real algebraic sets cannot be studied seriously without the use of semialgebraic sets. For example, a projection of a real algebraic set along a coordinate axis need not be a real algebraic set, but it is always a se... | Wikipedia - Real algebraic variety | null | null | null |
Real algebraic functions and Nash functions are examples of semialgebraic mappings. Piecewise polynomial mappings (see the Pierce–Birkhoff conjecture) are also semialgebraic mappings. | Wikipedia - Real algebraic variety | null | null | null |
Computational real algebraic geometry is concerned with the algorithmic aspects of real algebraic (and semialgebraic) geometry. The main algorithm is cylindrical algebraic decomposition. It is used to cut semialgebraic sets into nice pieces and to compute their projections. | Wikipedia - Real algebraic variety | null | null | null |
Real algebra is the part of algebra which is relevant to real algebraic (and semialgebraic) geometry. It is mostly concerned with the study of ordered fields and ordered rings (in particular real closed fields) and their applications to the study of positive polynomials and sums-of-squares of polynomials. (See Hilbert'... | Wikipedia - Real algebraic variety | null | null | null |
Nowadays, among non-QW solar cells, the III/V multi-junction solar cells are the most efficient, recording a maximum efficiency of 46% under high sunlight concentrations. Multi-junction solar cells are created by stacking multiple p-i-n junctions of different bandgaps. The efficiency of the solar cell increases with th... | Wikipedia - Quantum well | null | null | null |
As more quantum wells (QWs) are grown together, the material grows with dislocations due to the varying lattice constants. Dislocations reduce the diffusion length and carrier lifetime. Hence, QWs provide an alternate approach to multi-junction solar cells with minimal crystal dislocation. | Wikipedia - Quantum well | null | null | null |
Nowadays, data management has transferred over from local storage to the cloud. In the late 1990s and early 2000s, Salesforce and Amazon popularized the concept of internet-based services, which appealed to customers as it reduced in-house maintenance costs and increased flexibility in changing the needs of a business.... | Wikipedia - Data Management Platform | null | null | null |
Nowadays, palaeoproteomics is dominated by two mass spectrometry-based techniques: MALDI-ToF (matrix-assisted laser desorption/ionisation-time-of-flight) and LC-MS/MS. MALDI-ToF is used to determine the mass-to-charge (m/z) ratios of ions and their peak patterns. Digested peptides are spotted on a MALDI plate, co-cryst... | Wikipedia - Ancient protein | null | null | null |
It is a powerful analytical technique to separate, sequence and quantify complex protein mixtures. The first step in LC-MS/MS is liquid chromatography. Protein mixtures are separated in a liquid mobile phase using a stationary column. | Wikipedia - Ancient protein | null | null | null |
How liquid analytes interact with a stationary phase depends on their size, charge, hydrophobicity and affinity. These differences lead to distinct elution and retention time (when a component of a mixture exit a column). After chromatographic separation, protein components are ionised and introduced into mass spectrom... | Wikipedia - Ancient protein | null | null | null |
During a first mass scan (MS1), the m/z ratios of precursor ions are measured. Selected precursors are further fragmented and the m/z ratios of fragment ions are determined in a second mass scan (MS2). There are different fragmentation methods, for example, high-energy C-trap dissociation (HCD) and collision induced di... | Wikipedia - Ancient protein | null | null | null |
Protein sequence data can be downloaded from public genebanks (UniProt/NCBI) and exported as FASTA files for sequencing algorithms. Recently, open search engines such as MetaMorpheus, pFind and Fragpipe have received attention, because they make it possible to identify all modifications associated with peptide spectral... | Wikipedia - Ancient protein | null | null | null |
Nowadays, there are two nearly separate concepts of temperature, the thermodynamic concept, and that of the kinetic theory of gases and other materials. The zeroth law belongs to the thermodynamic concept, but this is no longer the primary international definition of temperature. The current primary international defin... | Wikipedia - Zeroth law of thermodynamics | null | null | null |
The zeroth law establishes thermal equilibrium as an equivalence relationship. An equivalence relationship on a set (such as the set of all systems each in its own state of internal thermodynamic equilibrium) divides that set into a collection of distinct subsets ("disjoint subsets") where any member of the set is a me... | Wikipedia - Zeroth law of thermodynamics | null | null | null |
This partitioning allows any member of the subset to be uniquely "tagged" with a label identifying the subset to which it belongs. Although the labeling may be quite arbitrary, temperature is just such a labeling process which uses the real number system for tagging. The zeroth law justifies the use of suitable thermod... | Wikipedia - Zeroth law of thermodynamics | null | null | null |
Such temperature scales bring additional continuity and ordering (i.e., "hot" and "cold") properties to the concept of temperature.In the space of thermodynamic parameters, zones of constant temperature form a surface, that provides a natural order of nearby surfaces. One may therefore construct a global temperature fu... | Wikipedia - Zeroth law of thermodynamics | null | null | null |
For example, if two systems of ideal gases are in joint thermodynamic equilibrium across an immovable diathermal wall, then P1V1/N1 = P2V2/N2 where Pi is the pressure in the ith system, Vi is the volume, and Ni is the amount (in moles, or simply the number of atoms) of gas. The surface PV/N = constant defines surfaces ... | Wikipedia - Zeroth law of thermodynamics | null | null | null |
These systems can now be used as a thermometer to calibrate other systems. Such systems are known as "ideal gas thermometers". In a sense, focused on in the zeroth law, there is only one kind of diathermal wall or one kind of heat, as expressed by Maxwell's dictum that "All heat is of the same kind". | Wikipedia - Zeroth law of thermodynamics | null | null | null |
But in another sense, heat is transferred in different ranks, as expressed by Sommerfeld's dictum "Thermodynamics investigates the conditions that govern the transformation of heat into work. It teaches us to recognize temperature as the measure of the work-value of heat. Heat of higher temperature is richer, is capabl... | Wikipedia - Zeroth law of thermodynamics | null | null | null |
Np(III) or Np3+ exists as hydrated complexes in acidic solutions, Np(H2O)3+n. It is a dark blue-purple and is analogous to its lighter congener, the pink rare-earth ion Pm3+. In the presence of oxygen, it is quickly oxidized to Np(IV) unless strong reducing agents are also present. Nevertheless, it is the second-least ... | Wikipedia - Neptunium compounds | null | null | null |
Np(IV) or Np4+ is pale yellow-green in acidic solutions, where it exists as hydrated complexes (Np(H2O)4+n). It is quite unstable to hydrolysis in acidic aqueous solutions at pH 1 and above, forming NpOH3+. In basic solutions, Np4+ tends to hydrolyze to form the neutral neptunium(IV) hydroxide (Np(OH)4) and neptunium(I... | Wikipedia - Neptunium compounds | null | null | null |
Np(V) or NpO+2 is green-blue in aqueous solution, in which it behaves as a strong Lewis acid. It is a stable ion and is the most common form of neptunium in aqueous solutions. Unlike its neighboring homologues UO+2 and PuO+2, NpO+2 does not spontaneously disproportionate except at very low pH and high concentration: 2 ... | Wikipedia - Neptunium compounds | null | null | null |
Np(VI) or NpO2+2, the neptunyl ion, shows a light pink or reddish color in an acidic solution and yellow-green otherwise. It is a strong Lewis acid and is the main neptunium ion encountered in solutions of pH 3–4. Though stable in acidic solutions, it is quite easily reduced to the Np(V) ion, and it is not as stable as... | Wikipedia - Neptunium compounds | null | null | null |
Np(VII) is dark green in a strongly basic solution. Though its chemical formula in basic solution is frequently cited as NpO3−5, this is a simplification and the real structure is probably closer to a hydroxo species like 3−. Np(VII) was first prepared in basic solution in 1967. In strongly acidic solution, Np(VII) is ... | Wikipedia - Neptunium compounds | null | null | null |
Nubian ibex live in rough, dry, mountainous terrain, where they eat mainly grasses and leaves, especially from Acacia trees (Genus Vachellia). They forage for food on the ground and may also rear up on their hind legs to reach leaves in trees. They can climb into trees while feeding. They reduce feeding on plants with ... | Wikipedia - Nubian ibex | null | null | null |
Preferred plants vary depending on the amount of rain; rainy winters result in higher feeding preference for annual plants over perennials. Ibex preferentially feed in spaces that are close to cliffs where they can easily escape predators, demonstrating a Landscape of Fear: the farther from cliffs, the more vigilant ib... | Wikipedia - Nubian ibex | null | null | null |
When alarmed, they emit a shrill call to alert other ibex of danger. They share their habitat with numerous other herbivores, including rock hyrax (Procavia capensis), Arabian oryx (Oryx leucoryx), gazelles (Genus gazella), and Asiatic wild ass (Equus hemionus). | Wikipedia - Nubian ibex | null | null | null |
Nubian ibex have a mutualistic relationship with Tristram's starling (Onycognathus tristrumil), a small bird that eats the parasites on the ibex's skin.They may host parasites including: the ibex fly (Lipoptena chalcomelanea), blood sucking lice (Linognathus africanus and Damalinia sp. ), ticks (Hyalomma rhipicephaloid... | Wikipedia - Nubian ibex | null | null | null |
NucPosDB: a database of nucleosome positioning in vivo and nucleosomics of cell-free DNA == References == | Wikipedia - Circulating free DNA | null | null | null |
Nuclear acoustic resonance implements physics from both nuclear magnetic resonance and acoustics, involving the use of laws of quantum mechanics to derive theory on acoustic resonance in objects with nuclei that have a nonzero angular momentum (I), with its magnitude given by I ( I + 1 ) {\displaystyle {\sqrt {I(I+1)}}... | Wikipedia - Nuclear acoustic resonance | null | null | null |
However, interactions of acoustic waves with nuclear spins do not guarantee the observation of acoustic resonance in objects. During the interactions, the acoustic waves experience a slight change in magnitude caused by the absorption by the object under nuclear spin, and the measurement of the change is crucial to obs... | Wikipedia - Nuclear acoustic resonance | null | null | null |
Nuclear astrophysics is made of many overlapping disciplines, spanning fields in astronomy, astrophysics and nuclear physics. In order to understand the origin of the elements, or the evolution and deaths of stars in galaxies, quite a broad base of knowledge is required. JINA-CEE created two virtual journals in order t... | Wikipedia - Joint Institute for Nuclear Astrophysics | null | null | null |
The JINA Virtual Journal debuted in 2003, and reviews a broad realm of nuclear astrophysics, followed by the SEGUE Virtual Journal in 2006, focusing more on Galactic Chemical and Structural evolution. Each week, the editors search almost 40 refereed journals for newly published articles. Editors review the articles, fl... | Wikipedia - Joint Institute for Nuclear Astrophysics | null | null | null |
Nuclear astrophysics remains as a complex puzzle to science. The current consensus on the origins of elements and isotopes are that only hydrogen and helium (and traces of lithium, beryllium, boron) can be formed in a homogeneous Big Bang (see Big Bang nucleosynthesis), while all other elements and their isotopes are f... | Wikipedia - Nuclear astrophysics | null | null | null |
The core hydrogen burning of stars, as it now occurs in the Sun, defines the main sequence of stars, illustrated in the Hertzsprung-Russell diagram that classifies stages of stellar evolution. The Sun's lifetime of H burning via pp-chains is about 9 billion years. This primarily is determined by extremely slow producti... | Wikipedia - Nuclear astrophysics | null | null | null |
Work that led to discovery of neutrino oscillation (implying a non-zero mass for the neutrino absent in the Standard Model of particle physics) was motivated by a solar neutrino flux about three times lower than expected from theories — a long-standing concern in the nuclear astrophysics community colloquially known as... | Wikipedia - Nuclear astrophysics | null | null | null |
26Al has a lifetime of a million years, which is very short on a galactic timescale, proving that nucleosynthesis is an ongoing process within our Milky Way Galaxy in the current epoch. Current descriptions of the cosmic evolution of elemental abundances are broadly consistent with those observed in the Solar System an... | Wikipedia - Nuclear astrophysics | null | null | null |
Li, Be, and B are believed to originate from spallation reactions of cosmic-ray nuclei such as carbon and heavier nuclei, breaking these apart. Unclear is, in which sources nuclei much heavier than iron are produced; for the slow and rapid neutron capture reactions, different sites are discussed, such as envelopes of s... | Wikipedia - Nuclear astrophysics | null | null | null |
Nuclear bomb and ballistics simulations at Los Alamos National Laboratory and Ballistic Research Laboratory (BRL), respectively. Monte Carlo simulation (voted one of the top 10 algorithms of the 20th century by Jack Dongarra and Francis Sullivan in the 2000 issue of Computing in Science and Engineering) is invented at ... | Wikipedia - Timeline of computational physics | null | null | null |
Nuclear engineers develop and research methods, machinery and systems concerning radiation and energy in subatomic levels. They require on-site experience and a bachelor's degree in Engineering. These engineers work in Nuclear Power plants and require licenses for practice while working in the power plant. They require... | Wikipedia - Power plant engineering | null | null | null |
Nuclear fission is the reverse process to fusion. For nuclei heavier than nickel-62 the binding energy per nucleon decreases with the mass number. It is therefore possible for energy to be released if a heavy nucleus breaks apart into two lighter ones. The process of alpha decay is in essence a special type of spontane... | Wikipedia - Nuclear research | null | null | null |
It is a highly asymmetrical fission because the four particles which make up the alpha particle are especially tightly bound to each other, making production of this nucleus in fission particularly likely. From several of the heaviest nuclei whose fission produces free neutrons, and which also easily absorb neutrons to... | Wikipedia - Nuclear research | null | null | null |
The fission or "nuclear" chain-reaction, using fission-produced neutrons, is the source of energy for nuclear power plants and fission-type nuclear bombs, such as those detonated in Hiroshima and Nagasaki, Japan, at the end of World War II. Heavy nuclei such as uranium and thorium may also undergo spontaneous fission, ... | Wikipedia - Nuclear research | null | null | null |
The conditions for the smallest critical mass require the conservation of the emitted neutrons and also their slowing or moderation so that there is a greater cross-section or probability of them initiating another fission. In two regions of Oklo, Gabon, Africa, natural nuclear fission reactors were active over 1.5 bil... | Wikipedia - Nuclear research | null | null | null |
Nuclear fusion occurs when the nuclei of two atoms approach closely enough for the nuclear force to pull them together into a single larger nucleus. The strong force is opposed by the electrostatic force created by the positive charge of the nuclei's protons, pushing the nuclei apart. The amount of energy that is neede... | Wikipedia - Beta limit | null | null | null |
Generally, lighter nuclei with a smaller number of protons and greater number of neutrons will have the greatest ratio of energy released to energy required, and the majority of fusion power research focusses on the use of deuterium and tritium, two isotopes of hydrogen. Even using these isotopes, the Coulomb barrier i... | Wikipedia - Beta limit | null | null | null |
Nuclear magnetic resonance (NMR) is a technique used to obtain physical, chemical, electronic and structural information about molecules due to the chemical shift of the resonance frequencies of nuclear spins in the sample. Its combination with electrochemical techniques can provide detailed and quantitative informatio... | Wikipedia - Spectroelectrochemistry | null | null | null |
Nuclear magnetic resonance (NMR) is an important example in the dynamics of two-state systems because it is involves the exact solution to a time dependent Hamiltonian. The NMR phenomenon is achieved by placing a nucleus in a strong, static field B0 (the "holding field") and then applying a weak, transverse field B1 th... | Wikipedia - Two-level quantum mechanical system | null | null | null |
As per the previous section, the solution to this equation has the Bloch vector precessing around ( ω 1 , 0 , ω 0 + ω r / 2 ) {\displaystyle (\omega _{1},0,\omega _{0}+\omega _{r}/2)} with a frequency that is twice the magnitude of the vector. If ω 0 {\displaystyle \omega _{0}} is sufficiently strong, some proportion o... | Wikipedia - Two-level quantum mechanical system | null | null | null |
Nuclear magnetic resonance spectroscopy (sometimes called MRS - magnetic resonance spectroscopy) is a non-invasive technique related to MRI (magnetic resonance imaging) for analyzing metabolic changes in vivo (from Latin: "within the living organism"), which can potentially be used for diagnosing brain tumors, Parkinso... | Wikipedia - Algorithmic cooling | null | null | null |
In MRS, the nuclear spins of the atoms of the metabolites are required to be with a certain degree of polarization, so the spectroscopy can succeed. Algorithmic cooling can be applied in vivo, increasing the resolution and precision of the MRS. Realizations (not in vivo) of algorithmic cooling on metabolites with 13C i... | Wikipedia - Algorithmic cooling | null | null | null |
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