Charge-storage response of separated ionic and electronic charge at an electrode-electrolyte interface. The differential capacitance is $C=dQ/dV$; it can vary with electrode potential, ion packing and surface structure.

A high-temperature alloy based on a nickel-rich disordered $\gamma$ matrix, commonly strengthened by ordered ${\gamma }^{\prime }$ precipitates and substitutional solutes.

A sum whose resulting value is a prime number. This is a condition on the value, rather than a requirement that the summation index run over prime numbers. Counting subsets with a prime-valued sum can use subset sum counts followed by a primality filter on the possible totals.

The Euler-Maclaurin formula relates a sum to an integral, endpoint corrections, and terms involving Bernoulli numbers and endpoint derivatives. Truncating after finitely many derivative corrections gives a remainder term that must be controlled; this supports accurate estimates of long sums.

A cyclic sulfonate ester. Alkoxide attack at a suitable primary carbon bound to the ring oxygen can open the ring by carbon–oxygen cleavage, leaving a sulfonate group.

A convention for the small fractional reduction of azimuthal gas speed due to radial pressure support. With $c_s^2=P_g/{\rho }_g$, radial balance gives $v_{g\varphi }^2=v_K^2(1-2\eta )$ and hence $v_{g\varphi }\simeq v_K(1-\eta )$. Other authors absorb the factor of two into the definition; the convention must accompany a drift formula.

For test particles with linear drag, negligible radial gas flow and negligible dust feedback, Sub-Keplerian rotation removes solid-particle angular momentum. The displayed inward velocity uses Stokes number $\mathrm{St}={\Omega }_K{t}_s$ and the pressure-gradient parameter of a protoplanetary disk. Drift is fastest at $\mathrm{St}=1$; the physical particle size at that point depends on the local gas and drag law.

For $\omega >0$ on $x>0$, use the regular finite branch at zero, decay at infinity, and a finite quadratic-form energy. For trial functions with $[x{y}^2{]}_0^{\infty }=0$, integration by parts givesThe Rayleigh quotient is at least $\omega$, with equality exactly for a nonzero multiple of $e^{-\omega x}$. Direct substitution verifies that this is an eigenfunction with eigenvalue $\omega$, so the lower bound is attained. The zero coefficient $p(0)=0$ makes this a singular-endpoint Sturm-Liouville problem; regularity replaces a prescribed zero endpoint value. Continuous piecewise differentiable trials of finite form energy are allowed in the Rayleigh-Ritz method, even if their derivative has a jump away from the endpoint.

A quark-line diagram can show how existing valence quarks are regrouped into outgoing hadrons while gluons exchange momentum and colour. Alternatively, a quark-antiquark pair can annihilate and create a different flavour pair with zero net flavour. Such drawings enforce global charge, baryon number and flavour constraints; they are not controlled perturbative calculations of an exclusive low-energy hadronic amplitude because binding is nonperturbative.

For a thin lens, relative arrival times follow the difference of $\frac{1}{2}|\theta -\beta {|}^2-\psi (\theta )$ between images, multiplied by $(1+z_l)D_l{D}_s/(c{D}_{ls})$. Both geometry and gravitational potential contribute; an additive delay common to all images is unobservable.

A palindrome is a finite string equal to its reversal. For example, the strings $010$ and $0110$ are palindromes.

An infinite binary word is Sturmian if it has exactly $n+1$ distinct contiguous subwords of length $n$ for every positive integer $n$.

A substring is a contiguous segment of a string. It differs from a subsequence, whose selected characters need not be adjacent.

A cyclic rotation of a string $xy$ is the string $yx$, where $x$ and $y$ are consecutive pieces. For example, rotating ABC left once gives BCA. A length-$n$ string has $n$ rotation positions, though repeated letters can make some resulting strings identical.