Ferrocyanide is the hexacyanoferrate(II) anion, $[\mathrm{Fe}(\mathrm{CN}{)}_6{]}^{4-}$. Six cyanide ligands surround formally iron(II), giving an approximately octahedral coordination complex.

One-electron oxidation gives ferricyanide without requiring loss of the whole ligand framework. Distinguishing a coordinated cyanide ligand from free cyanide is essential when describing the chemical species.

Given a particular input $x$, finding a different input $x^{\prime }$ with the same digest should be computationally infeasible. Preimage resistance asks for any input matching a given digest; collision resistance allows choosing both colliding inputs. These are different security requirements.

Chest discomfort associated with transient inadequate oxygen supply to the myocardium relative to its requirements. Several mechanisms can produce the syndrome.

Transient constriction of a coronary artery. It can reduce blood flow and produce ischemia without a fixed narrowing of the same severity, connecting dynamic vascular tone with cardiac symptoms.^[ref]

Disorder of the small vessels supplying the heart muscle. Impaired regulation of local flow can cause ischemia even when the major coronary arteries lack a large obstructing lesion.^[ref]

For a scalar conservation law $u_t+q(u{)}_x=0$, an entropy condition restricts its weak solutions to physically admissible ones. For every convex entropy function $\eta$, define an entropy flux by $Q^{\prime }={\eta }^{\prime }{q}^{\prime }$. The displayed inequality is imposed in the distributional sense. Positive diffusion explains this choice: for $u_t+q(u{)}_x=ϵ[D(u)u_x{]}_x$ with $D>0$, the entropy balance is $\eta (u{)}_t+Q(u{)}_x=ϵ[{\eta }^{\prime }(u)D(u)u_x{]}_x-ϵ{\eta }^{\prime \prime }(u)D(u)u_x^2$. The last term is nonpositive, and an appropriate vanishing-diffusion limit yields the entropy inequality. For a strictly concave flux and a single shock, this selects states with incoming characteristics, rather than a discontinuity whose characteristics spread outward.

A condensed matter physicist studies condensed matter physics through mathematical theory, observation or experiment. The field determines the relevant physical systems and measurements, while the individual biographies below connect particular contributions with their scientific ideas.

The number of elementary operations on bits required by an algorithm. Arithmetic-operation counts treat operations on entire integers as units, whereas bit complexity charges for the sizes of their operands. An algorithm using few multiplications can therefore require substantially more bit operations when the operands grow. State the model when comparing bounds for repeated squaring or dynamic programming counts.

A transformation that computes a repeated program expression once and reuses its saved result when the value is known not to have changed. A repeated load can be reused only when intervening stores, calls or other changes cannot alter the relevant location. Alias analysis helps establish that fact. Maximal address sharing can be counterproductive if instruction selection could otherwise fold an address addition into register-offset addressing.

Analysis of whether two accesses may designate the same storage location. Common subexpression elimination must not reuse a previously loaded value after a store that might change that location, unless an additional argument justifies it. A saved memory address can remain valid even though a value previously loaded at that address is invalidated.

Choosing target-machine instructions to implement an intermediate representation. A memory operand using register-offset addressing can cover both an address addition and a load or store; computing the full address into a temporary variable can prevent that covering and add an unnecessary instruction.

A choice among enabled communication events, committing one ready event. An event whose Boolean guard is false is not offered. Output events must be selected before their value-producing expression or post-send state update is performed.

The capacity of a chemical substance to undergo combustion with a suitable oxidizing agent. It is a property, distinct from the combustible substance possessing it.

A diffusion flame sustained by the evaporation and chemical breakdown of wax delivered through a wick by capillary action.

A flame in which fuel and oxidizing agent enter separately and react as they mix.

A material used as a source of released chemical energy, commonly by reaction with an oxidizing agent during combustion.

A controlled test in which a taper is exposed to a specified gas mixture to determine whether its candle flame persists under a fixed protocol. The result depends on composition, flow, time, taper and thermal conditions; it is not a general test of whether the gas can safely be breathed.

A fibrillar collagen prominent in reticular supporting networks, including those of lymph nodes.

The aqueous condensate and wash liquid from historical gasworks, containing dissolved Ammonia and other constituents.

The complex condensable organic fraction produced during destructive distillation of coal.