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Historical formulation name; composition is identified by pharmacopoeial edition.

Historical formulation name; composition is identified by pharmacopoeial edition.

V. Cannella and J. A. Mydosh measured low-field magnetic susceptibility of gold-iron alloys using a mutual inductance bridge. Moving samples into and out of the pickup arrangement separated their signal from the background. Cooling revealed sharp susceptibility cusps; changing concentration, sample shape and applied magnetic field tested their interpretation. Larger fields rounded the peaks. Their 1972 paper interpreted low-concentration ordering in antiferromagnetic terms: the cusp alone did not demonstrate Parisi's later theory.^[ref]

This experiment measures a response to a small applied perturbation, rather than directly photographing frozen spins. Comparing field strengths is essential because the probing magnetic field itself changes the response.^[ref]

A condition involving excessive accumulation of iron. Venesection removes iron within red blood cells and stimulates use of further iron in their replacement. ^[ref]

Venesection: removal of iron-containing red blood cells and replacement drawing on excess iron.

An engineer associated with the Bessemer process. National Portrait Gallery, sitter biography and dated portraits.

Primary patent specification by Henry Bessemer; cited specification and final claim concern air-blast conversion sustained by oxidation of constituents of molten iron.

Heinrich Barkhausen's 1919 report used iron, a 300-turn pickup coil, moving magnet, amplified telephone readout and galvanometer. Removing iron corrected drive pickup. ^[ref]

A modern primary experiment by Gianfranco Durin and Stefano Zapperi used annealed iron–silicon strips and amorphous alloys. A 60 cm solenoid swept a triangular magnetic field intensity; a 50-turn pickup coil, wound within 1 mm, sensed the specimen. A preamplifier with a 3–20 kHz low-pass filter preceded sampling. Measurements selected the central hysteresis region dominated by magnetic domain wall motion. Above-background threshold crossings defined event durations; integrating between crossings defined event sizes. These are reported procedures, rather than data generated for the diagrams.^[ref]

For this stationary implementation, secure a thin ferromagnet and its pickup coil inside a longer drive solenoid, keeping their relative positions fixed. Drive the solenoid with a slow triangular electric current, monitor that electric current, and record the amplified, filtered induced electromotive force with a digitizer. A speaker may make suitable frequencies audible, but the voltage record is needed for quantitative analysis. Slow variation of the drive does not require smooth magnetization. A triangular drive supplies an approximately constant applied-field sweep rate along each ramp; it does not guarantee constant instantaneous $dM/dt$.

A proposed control sequence makes the inference testable. First record the electronics background with no drive. Repeat the same sweep with the specimen removed, retaining coil geometry: mutual induction from the drive can itself induce a voltage. A matching empty pickup coil wired in opposition can suppress common drive pickup, after checking its matching. Compensation of air flux by an opposed coil is an established method.^[ref] Then restore the specimen, repeat both sweep directions, reduce sweep rate, and compare the same hysteresis region with fixed amplifier gain, filter and threshold. Monitor drive irregularities and mechanical vibration; either can generate spurious pulses. These controls are recommendations for the schematic, rather than undocumented controls attributed to the modern paper.

A genuine material contribution should differ from the blank-coil record and change reproducibly with the magnetic preparation and sweep region. Quieting the drive tests drive-correlated pickup, but a held field need not eliminate all delayed material motion. Reversing the sweep is a consistency check on signed changes, not a demand that individual events retrace. A changing pulse count under a different filter or threshold cannot by itself establish changed microscopic dynamics. The useful inference is intermittent collective magnetization change within the instrument's signal bandwidth, with spatial detail left unresolved.

A chemical compound containing iron; the oxidation state and associated ligands distinguish medicinal preparations.

Journal of the American Chemical Society 106, 4966–4977. Diiron spiro structures and triiron products show phosphorus–metal and nitrogen–metal bonding; triiron compound 3 is also obtained from diiron compound 2 and neutral iron carbonyls.

The compound with formula $\mathrm{Fe}{\mathrm{S}}_2$. Its conversion with metallic lithium consumes four Li per formula unit and can form iron and two lithium sulfide units; that electron inventory sets an ideal battery capacity.

Conversion of an iron-bearing ore into metallic iron, for example by carbon monoxide reduction in a blast furnace.

Control of iron uptake, storage, utilization and release. post-transcriptional regulation can coordinate these processes without requiring all regulated transcripts to change in the same direction.

A family of iron hydroxide materials. Their precipitation can obscure colour tests unless the analytical sequence controls the pH.

The +2 oxidation state of iron; the aqueous cation is commonly represented by $\mathrm{F}{\mathrm{e}}^{2+}$.

The +3 oxidation state of iron; the aqueous cation is commonly represented by $\mathrm{F}{\mathrm{e}}^{3+}$.

The ferric chloride, historically called perchloride of iron; it is not a perchlorate.

The ferric nitrate, historically called pernitrate of iron.