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Electronics manufacturing services

Electronics manufacturing services, often called contract manufacturing, is an industry in which companies design, manufacture, test, and repair electronics on behalf of original equipment manufacturers.

Electrons on helium

Electrons on helium are electrons trapped a few nanometers above liquid helium by their image charge, forming a clean two-dimensional electron gas studied since the 1970s and proposed in 1999 as a quantum computing platform.

Electronvolt

The electronvolt (eV), or megaelectronvolt scale unit, is a non-SI energy unit equal to exactly 1.602176634 × 10⁻¹⁹ joule, standard in atomic, nuclear, and particle physics.

Oct 20, 2026

Electronystagmography

Electronystagmography (ENG, electrooculography) is an electrode-based test recording eye movements via the corneo-retinal potential to evaluate vestibular and oculomotor nerves in dizziness; largely replaced by videonystagmography but still used when eyes-closed recording is needed.

Electrooculography

Electrooculography (EOG) is a non-invasive recording technique that tracks eye movements and tests retinal pigment epithelium function by measuring the eye's corneoretinal standing potential with skin electrodes.

Electroorganic synthesis

Electroorganic synthesis is the use of electron transfer at electrodes to drive organic reactions, replacing stoichiometric chemical oxidants and reductants with electrical current, often under mild conditions.

Electroosmotic flow

Electroosmotic flow (EOF) is the motion of an electrolyte solution past a charged solid surface under an applied electric field, a standard pumping method in microfluidics.

Electroperú

Electroperú (Empresa de Electricidad del Perú S.A.) is a Peruvian state-owned electricity company founded in 1972, whose Mantaro complex supplies about 13 percent of Peru's energy.

Electrophile

An electrophile, from "electron-loving," is a reagent that accepts both bonding electrons from its reaction partner, the nucleophile. Electrophiles are Lewis acids and organize most of polar organic chemistry.

Electrophilic addition

Electrophilic addition is an organic reaction in which an electrophile adds across the double or triple bond of an unsaturated molecule, the characteristic reaction class of alkenes.

Electrophilic amination

Electrophilic amination is a synthetic organic chemistry method forming carbon–nitrogen bonds by transferring an electrophilic amino group to organometallic compounds or enolates, inverting usual amine-synthesis polarity.

Electrophilic aromatic substitution

Electrophilic aromatic substitution is an organic reaction in which an electrophile replaces a hydrogen atom on an aromatic ring such as benzene, most often by halogenation, nitration, sulfonation, or Friedel–Crafts reactions.

Electrophilic fluorination

Electrophilic fluorination is a chemical synthesis method that transfers fluorine to electron-rich sites in organic molecules using reagents such as Selectfluor and NFSI, forming C–F, N–F, or O–F bonds in one step.

Electrophilic halogenation

Electrophilic halogenation is an electrophilic aromatic substitution in which bromine or chlorine replaces hydrogen on an aromatic ring, using a Lewis acid catalyst such as FeBr₃.

Electrophilic substitution

Electrophilic substitution is an organic reaction in which an electrophile replaces a hydrogen on an aromatic ring, installing halogen, nitro, sulfonic acid, alkyl, or acyl groups.

Electrophilicity index

The electrophilicity index (ω) is a reactivity descriptor from conceptual DFT, defined by Parr, von Szentpály, and Liu in 1999 as electronegativity squared divided by twice chemical hardness.

Electrophoresis

Electrophoresis, also called ionophoresis, is a laboratory technique in which charged molecules such as DNA, RNA, and proteins migrate in an electric field, separating mixtures by size and charge.

Electrophoretic deposition

Electrophoretic deposition, also called electrophoretic painting or electro-coating, deposits charged particles suspended in a liquid onto an electrode under an applied electric field, forming coatings or solid bodies.

Electrophoretic light scattering

Electrophoretic light scattering is an optical characterization technique that measures the electrophoretic mobility of dispersed particles by detecting the Doppler shift of scattered laser light, yielding zeta potential, a standard indicator of colloidal stability.

Electrophoretic mobility shift assay

The electrophoretic mobility shift assay (EMSA), also called the band shift assay, is a gel technique that detects protein–nucleic acid binding, first reported by Garner and Revzin in 1981.

Electrophoretic separation

Electrophoretic separation is a bench technique that moves charged biomolecules such as DNA, RNA, or proteins through a gel under an electric field, sorting them chiefly by size.

Electrophotocatalysis

Electrophotocatalysis, also called electrophotochemistry, is a synthetic method in which a catalyst is activated electrochemically and then photoexcited, so electricity and light jointly drive chemical transformations.

Electrophotocatalysis with cyclopropenium ions

Electrophotocatalysis with cyclopropenium ions is a synthetic method, introduced in 2019, in which anodically oxidized trisaminocyclopropenium ions act as powerful photocatalysts for oxidant-free C–H functionalization.

Electrophysiological mapping

Electrophysiological mapping is a clinical technique recording electrical activity from many points on cardiac or cortical tissue, localizing abnormal conduction paths and seizure foci for treatment planning.

Electrophysiology

Electrophysiology is the study of the electrical properties of biological macromolecules, cells, tissues, and organs, ranging from currents through single ion channels to clinical EEG, ECG, and EMG testing.

Electrophysiology recording

Electrophysiology recording is a laboratory technique that measures the electrical activity of living cells, such as neurons, using electrodes to detect membrane voltage or ionic currents.

Electrophysiology study

Electrophysiology study (EP study, invasive cardiac electrophysiology): catheter-based heart test recording electrical activity to locate arrhythmias, test drugs, map before ablation, and assess sudden cardiac death risk; 1-4 hours, mortality about 0.2%.