Historical steel made by welding and forging suitable steel bars, often from blister steel.

Steel melted in a crucible to improve compositional uniformity relative to incompletely homogenized starting stock.

The Bessemer process converts molten pig iron toward steel by blowing air through the liquid. Oxidation of constituents, especially silicon and carbon, releases heat within the bath. This combination of mixing, chemical reaction and internal heating made rapid bulk conversion possible without supplying all the required heat from an external fire.^[ref]

The product depends on the feed chemical composition, the extent of oxidation and subsequent adjustment of the carbon content. Removing carbon alone does not guarantee useful steel: other constituents also affect its properties. This illustrates why a successful process in metallurgy must control both its desired reaction and the fate of unwanted constituents. Henry Bessemer's patent describes the central idea of generating heat by reaction inside the molten material.

An iron–manganese–carbon alloy historically used to adjust steel composition.

A dye used in tissue investigation, notably for detecting amyloid through characteristic staining and optical behavior. Dye binding supplies evidence about an ordered deposit rather than identifying the precursor protein by itself.

Staining that identifies organisms or material retaining dye after an acid-containing decolorization step. The property reflects cell-envelope chemistry; a positive stain alone does not identify every species or demonstrate viability.

A histological stain that detects certain carbohydrate-rich structures after chemical oxidation produces reactive groups. The staining pattern identifies chemical properties and location rather than a unique molecule.

A property of the evaluation stack at a specified program point. For expression compilation, a useful contract is that generated code transforms any incoming stack $\sigma$ into $\sigma ,v$, leaving all pre-existing values unchanged. For a statement, a useful contract is preservation of $\sigma$.

A designated stack symbol marking its bottom. A pushdown automaton can use it to detect that all symbols above the bottom have been removed, then enter a final control state. The marker must be distinct from the other stack alphabet symbols.

A stack supporting access to its minimum in constant time complexity when its contents are nonempty. Each linked list node stores its value and the minimum of the suffix beginning there. Pushing computes one new cached minimum; popping reveals the previous cached minimum. Keeping one cached value per node handles repeated minima without a special case.

A sensory pathway carrying information including pain and temperature; injury to crossing fibres in the central spinal cord can produce dissociated sensory loss.

The anterior horn is the ventral gray-matter region of the spinal cord, containing somatic motor neurons and associated circuitry. Its organization links spinal segments to muscle groups. It is distinct from the roots through which motor axons leave the cord.

A descending motor pathway carries signals from more rostral neural centers toward brainstem or spinal circuits contributing to movement. Its effect depends on intervening interneurons and motor neurons. An anatomical projection is therefore not necessarily a direct command to one muscle.

Predicting a branch's continuation before its outcome is known, allowing instruction fetch and potentially execution to proceed. An incorrect prediction requires recovery of younger speculative work.

Build a max-heap in an array, then repeatedly exchange its root with the last element of the active heap and restore heap order by heapify down. The inactive suffix grows in ascending order. Bottom-up heap construction costs $O(n)$ because the number of nodes at height $h$ decreases geometrically, and the extraction phase costs $O(n\log n)$. Iterative sifting uses constant auxiliary storage. Long-distance exchanges can reverse equal-key records, so the usual version does not provide stable sorting.

First exchange the endpoints of the current subarray if they are out of order. For current length $m>2$, put $k=\lfloor m/3\rfloor$ and recursively sort its first $m-k$ entries, its last $m-k$ entries, then its first $m-k$ entries again. Each child has length $\lceil 2m/3\rceil$; the split must use the current subproblem length. The master theorem gives exponent ${\log }_{3/2}3\approx 2.7095$, worse than quadratic. The usual algorithm is not stable: endpoint exchange on $[2_a,2_b,1]$ leaves the equal-key records reversed after sorting.

A sorting algorithm that sorts memory-sized runs and merges them using storage-backed passes. It can also eliminate repeated database tuples.

A solution whose concentration has been established for use as a measurement reference, for example in titration. It can be prepared from a primary standard or established by titrant standardization. The word “standard” does not imply one universal concentration.

Assign distinct responsibilities to components with explicit interfaces, so one responsibility can change without requiring unrelated changes elsewhere. For example, a model-view-controller application separates domain state, presentation and input interpretation. The Observer pattern can communicate a coherent state change to several views while keeping concrete display details out of the model. The separation should follow actual responsibilities; multiplying classes without a clear boundary does not establish it.

The organization of a software system's major components, their responsibilities and their interactions. A software architecture constrains which components own state and which may request or observe changes. Model-view-controller is one example for interactive applications.