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Divergence theorem
The divergence theorem, also called Gauss's theorem or Ostrogradsky's theorem, states that a vector field's outward flux through a closed surface equals the volume integral of its divergence.
Divergent boundary
A divergent boundary, also known as a divergent plate or constructive boundary, is where two tectonic plates pull apart and magma rising between them creates new crust.
Divergent series
A divergent series, also known as a nonconvergent series, is an infinite series whose sequence of partial sums does not approach a finite limit, diverging either to infinity or by oscillating.
Divergent synthesis
Divergent synthesis is a chemical strategy in which one common intermediate is converted through parallel branching steps into many products, used in dendrimer chemistry and combinatorial library synthesis.
Diversity-oriented synthesis
Diversity-oriented synthesis (DOS) is a synthetic chemistry strategy, introduced by Stuart L. Schreiber in 2000, that prepares many structurally varied small molecules in few steps for drug discovery screening.
Divertor
A divertor is a magnetic-confinement fusion device component that intercepts plasma escaping the core and directs its heat and particles onto engineered target plates, as in tokamaks and stellarators.
Divertor detachment
Divertor detachment is a tokamak operating regime in which the plasma separates from the divertor target, sharply reducing heat and ion fluxes to the target plates.
Divertor detachment control
Divertor detachment control is the feedback regulation of plasma detachment in a tokamak divertor, using gas puffing to cut target heat loads while preserving core confinement.
Divide–expand–consolidate coupled cluster
Divide–expand–consolidate coupled cluster, known as DEC, is a local correlation method in quantum chemistry developed by Poul Jørgensen and coworkers at Aarhus University, giving linear-scaling calculations with rigorous error control.
Divinyl ether
Divinyl ether (vinyl ether, divinyl oxide) is a volatile ether used as an inhalational anesthetic in the 1930s and now mainly as a monomer in polymer chemistry.
Divinylbenzene
Divinylbenzene (DVB) is an aromatic hydrocarbon, C₁₀H₁₀, with two vinyl groups on a benzene ring, used as a cross-linking monomer in ion exchange resins and chromatography media.
Divisia index
The Divisia index is an index number whose growth rate is the expenditure-share-weighted average of its components' growth rates, introduced by François Divisia in 1926.
Divisibility (ring theory)
Divisibility in ring theory studies when one element of a ring divides another, generalizing integer divisibility; properties like unique factorization into primes can fail in general rings.
Divisibility rule
A divisibility rule, also called a divisibility test, is a shortcut that checks whether an integer is divisible by another by examining its digits instead of dividing.
Division (mathematics)
Division is the arithmetic operation of taking the ratio of two numbers, the inverse of multiplication, where x is the dividend, y the divisor, and the result the quotient.
Division algorithm
The division algorithm is a theorem of elementary number theory: any integer divided by a nonzero divisor yields a unique quotient and remainder, with 0 ≤ r < divisor.
Division by zero
Division by zero, also called dividing by zero or a zero denominator, is dividing a number by zero, undefined for real numbers, with 0/0 an indeterminate form.
Division ring
A division ring, also called a skew field, is a nonzero ring in which every nonzero element has a multiplicative inverse, while multiplication need not commute.
Division sign
The division sign (÷), also called the obelus, is a mathematical symbol used to indicate division. Johann Rahn first used it for division in his 1659 book Teutsche Algebra.
Divisor
A divisor (also called a factor) of an integer n is an integer that divides n with no remainder; its study is the starting point of number theory.
Divisor (algebraic geometry)
In algebraic geometry, a divisor is a formal object on an algebraic variety or scheme recording codimension-1 subvarieties with integer multiplicities, tied to line bundles through the Picard group.
Divisor function
The divisor function, also called the sum-of-divisors function, is the number-theoretic function σk(n) summing the k-th powers of n's divisors; σ0 counts them and σ1 adds them up.
Dixie Fire
The Dixie Fire was a 2021 wildfire in the northern Sierra Nevada, ignited by a tree contacting a PG&E line, that burned 963,309 acres and destroyed Greenville.
Dixon's Q test
Dixon's Q test is a statistical test for detecting a single outlier in a small univariate sample, introduced by W. J. Dixon in 1950 and standard in analytical chemistry.
Dizocilpine
Dizocilpine, also known as MK-801, is a non-competitive NMDA receptor antagonist developed by Merck in 1982; restricted medically, it is a standard research tool in schizophrenia studies.
DLin-KC2-DMA
DLin-KC2-DMA, known as KC2, is a synthetic ionizable cationic lipid used in lipid nanoparticles to deliver siRNA, and the ancestor of the clinically approved lipid MC3.
DLin-MC3-DMA
DLin-MC3-DMA, also known as MC3, is a synthetic ionizable cationic lipid used in lipid nanoparticles to deliver RNA, most notably in Onpattro (patisiran), the first FDA-approved siRNA drug in 2018.
DLPNO-CCSD(T)
DLPNO-CCSD(T) is a reduced-scaling quantum chemical method developed by Frank Neese and coworkers in 2013 that approximates the canonical CCSD(T) "gold standard", achieving near-linear scaling while recovering about 99.9% of its correlation energy.
DLVO theory
DLVO theory, the Derjaguin–Landau–Verwey–Overbeek theory, is the classical theory of colloid stability, developed by Derjaguin and Landau in 1941 and independently by Verwey and Overbeek in 1948.
DM Tau
DM Tau is a young T Tauri star in the constellation Taurus, about 470 light-years away, surrounded by a protoplanetary disk with two dust rings.