All articles starting with F

Formamidase

Formamidase (EC 3.5.1.49, AmiF/FmdA) is a nitrilase-superfamily hydrolase converting formamide to formate and ammonia, letting microbes use formamide as a nitrogen source; H. pylori AmiF hydrolyzes formamide only.

Formamide

Formamide, also known as methanamide or carbamaldehyde, is the simplest amide, a colorless liquid used as a solvent and chemical intermediate, and a molecule detected in interstellar space.

Formamidinium lead iodide

FAPbI3, or formamidinium lead triiodide, is a halide perovskite whose 1.48 eV bandgap makes it the leading light absorber in perovskite solar cells above 26% efficiency.

Formamidinium perovskite solar cells

Formamidinium perovskite solar cells are photovoltaic devices whose absorber, formamidinium lead triiodide (FAPbI₃), offers a narrow 1.48 eV band gap and certified efficiencies of 26.7%, though stabilizing its photoactive black phase remains the main challenge.

Formamidinium tin iodide

Formamidinium tin iodide (FASnI₃) is a lead-free tin halide perovskite with a 1.41 eV band gap, the composition behind the highest efficiencies for tin perovskite solar cells.

Formant

A formant is a broad peak in the spectral envelope of a sound caused by resonance; in speech, the vocal tract's formants distinguish one vowel from another.

Formate dehydrogenase

Formate dehydrogenase (FDH, EC 1.17.1.9) catalyzes reversible formate/CO2 interconversion. Two classes: NAD+-dependent metal-free enzymes and Mo/W-containing prokaryotic enzymes of the DMSO reductase family; used for NADH recycling and CO2 reduction.

Formate hydrogenlyase maturation HycH

HycH (formate hydrogenlyase maturation protein) is a 136-residue E. coli hyc operon protein required for maturation of hydrogenase 3 but not part of the functional FHL-1 complex; it acts as a dual-function assembly chaperone.

Formate pathway in CO2 hydrogenation

The formate pathway in CO2 hydrogenation is a reaction mechanism in which CO2 is hydrogenated via a formate intermediate to methanol, avoiding the CO route, on Cu/ZnO catalysts.

Formate-dependent cytochrome c nitrite reductase, c552 subunit

Formate-dependent cytochrome c nitrite reductase, c552 subunit, commonly called NrfA, is a soluble periplasmic pentaheme cytochrome c enzyme catalyzing the six-electron reduction of nitrite to ammonium, the final step of DNRA.

Formate-dependent phosphoribosylglycinamide formyltransferase

Formate-dependent phosphoribosylglycinamide formyltransferase (PurT, GAR transformylase 2) is a bacterial, ATP- and formate-dependent enzyme of de novo purine biosynthesis, redundant with folate-dependent PurN, supplied formate by PurU, and structurally unrelated to it.

Formation (association football)

Formation (association football): the numbered arrangement of a team's ten outfield players, e.g. 4-4-2, 4-3-3, 3-5-2, 4-2-3-1. Evolved from the 2-3-5 pyramid; shapes shift by phase of play and affect physical and tactical performance.

Formation (song)

Formation is a 2016 Beyoncé song, surprise-released February 6 on Tidal as the lead single of Lemonade, produced by Mike WiLL Made-It with Swae Lee, performed at Super Bowl 50 the next day.

Formation and evolution of globular clusters

The formation and evolution of globular clusters covers how dense systems of roughly 100,000 old stars formed, peaked at redshift 2.5, and dissolved into galactic halos.

Formation and evolution of the Solar System

The Solar System formed about 4.6 billion years ago from the collapse of a giant molecular cloud, with planets accreting from a disk around the young Sun.

Formation constant

The formation constant, or stability constant, is the equilibrium constant for a metal ion binding one or more ligands to form a coordination complex in solution.

Formation control

Formation control is a branch of cooperative control that coordinates groups of robots, vehicles, or spacecraft so they maintain specified geometric configurations while moving through an environment.

Formation microimager

The formation microimager is a wireline well-logging tool producing high-resolution electrical images of the borehole wall; its successor, the Fullbore Formation MicroImager (FMI), was introduced by Schlumberger.

Sep 24, 2026

Formation of the Preobrazhensky and Semyonovsky regiments

The formation of the Preobrazhensky and Semyonovsky regiments (Создание потешных полков) transformed Peter I's childhood amusement troops, begun in 1683 near Moscow, into the founding units of the Russian Guard.

Formation of the samurai

The formation of the samurai is the emergence of Japan's warrior class, the bushi, between the ninth and twelfth centuries, culminating in Minamoto no Yoritomo's Kamakura government in 1185.

Sep 24, 2026

Formation of the USSR

The Formation of the USSR (Образование СССР) was the union of Russia, Ukraine, Belorussia, and Transcaucasia into a single state, proclaimed in Moscow on 30 December 1922.

Sep 29, 2026

Formation testing

Formation testing is a downhole well-logging technique, developed in the mid-1950s, that measures fluid pressure in rock formations and retrieves samples, a central tool of reservoir characterization.

Formation8 Partners

Formation8 Partners, commonly styled Formation 8, was a Palo Alto-based venture capital firm founded in 2012 that backed smart enterprise and energy startups, winding down in 2015.

Formative assessment

Formative assessment, also called assessment for learning, is a planned, ongoing process in which teachers and students use evidence of learning to adjust instruction, unlike summative assessment.

Formazan

A formazan is a highly colored nitrogen-rich organic compound, known since the late 1800s, used as a dye and formed in tetrazolium assays of cell viability such as the MTT assay.

Formentera

Formentera, the smallest inhabited Balearic island (83 km², Pityusic Islands with Ibiza), has no airport and is reached by ferry. Known for Ca na Costa megalithic tomb, UNESCO-listed Posidonia meadows, and vehicle limits under Law 7/2019.

Formentera Partners

Formentera Partners is an Austin, Texas private equity firm, founded in 2020 by Bryan Sheffield and Blake London, that buys and operates mature onshore oil and gas assets.

Former and decommissioned reservoirs of Europe

Former and decommissioned reservoirs of Europe are impounding basins permanently emptied or drawn down, by full demolition, notch cutting, or draining, with documented cases including Krebsbach Dam and Lower Neuadd.

Former and Latter Seven Masters

The Former and Latter Seven Masters (前七子, 后七子) were two Ming dynasty literary groups, led by Li Mengyang and Li Panlong, who championed the archaist revival.