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Topic Review
Electro-Osmosis
Electroosmotic flow (or electro-osmotic flow, often abbreviated EOF; synonymous with electroosmosis or electroendosmosis) is the motion of liquid induced by an applied potential across a porous material, capillary tube, membrane, microchannel, or any other fluid conduit. Because electroosmotic velocities are independent of conduit size, as long as the electrical double layer is much smaller than the characteristic length scale of the channel, electroosmotic flow will have little effect. Electroosmotic flow is most significant when in small channels. Electroosmotic flow is an essential component in chemical separation techniques, notably capillary electrophoresis. Electroosmotic flow can occur in natural unfiltered water, as well as buffered solutions.
  • 1.2K
  • 29 Nov 2022
Topic Review
Measurement of Compact Muon Solenoid Magnetic Field
The Compact Muon Solenoid (CMS) is a general-purpose detector at the Large Hadron Collider. The goal of CMS experiment is to investigate a wide range of physics, including the search for the Higgs boson, extra dimensions, and particles that could make up dark matter. The CMS magnetic field is provided by a wide-aperture superconducting thin solenoid with a diameter of 6 m and a length of 12.5 m, where a central magnetic flux density of 3.8 T is created by an operational direct current of 18.164 kA.
  • 1.1K
  • 15 Feb 2022
Topic Review
Stoner–Wohlfarth Model
The Stoner–Wohlfarth model is a widely used model for the magnetization of single-domain ferromagnets. It is a simple example of magnetic hysteresis and is useful for modeling small magnetic particles in magnetic storage, biomagnetism, rock magnetism and paleomagnetism.
  • 1.1K
  • 14 Oct 2022
Topic Review
North Magnetic Pole
The North Magnetic Pole is a wandering point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards (in other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down). There is only one location where this occurs, near (but distinct from) the Geographic North Pole and the Geomagnetic North Pole. The North Magnetic Pole moves over time according to magnetic changes and flux lobe elongation in the Earth's outer core. In 2001, it was determined by the Geological Survey of Canada to lie west of Ellesmere Island in northern Canada at 81°18′N 110°48′W / 81.3°N 110.8°W / 81.3; -110.8 (Magnetic North Pole 2001). It was situated at 83°06′N 117°48′W / 83.1°N 117.8°W / 83.1; -117.8 (Magnetic North Pole 2005 est) in 2005. In 2009, while still situated within the Canadian Arctic at 84°54′N 131°00′W / 84.9°N 131°W / 84.9; -131 (Magnetic North Pole 2009), it was moving toward Russia at between 55 and 60 km (34 and 37 mi) per year. As of 2019, the pole is projected to have moved beyond the Canadian Arctic to 86°26′52.8″N 175°20′45.06″E / 86.448°N 175.34585°E / 86.448; 175.34585 (Magnetic North Pole 2019 est). Its southern hemisphere counterpart is the South Magnetic Pole. Since Earth's magnetic field is not exactly symmetrical, the North and South Magnetic Poles are not antipodal, meaning that a straight line drawn from one to the other does not pass through the geometric center of Earth. Earth's North and South Magnetic Poles are also known as magnetic dip poles, with reference to the vertical "dip" of the magnetic field lines at those points.
  • 1.0K
  • 17 Oct 2022
Topic Review
Solar Energy Conversion
Solar energy conversion describes technologies devoted to the transformation of solar energy to other (useful) forms of energy, including electricity, fuel, and heat. It covers light-harvesting technologies including traditional semiconductor photovoltaic devices (PVs), emerging photovoltaics, solar fuel generation via electrolysis, artificial photosynthesis, and related forms of photocatalysis directed at the generation of energy rich molecules. Fundamental electro-optical aspects in several emerging solar energy conversion technologies for generation of both electricity (photovoltaics) and solar fuels constitute an active area of current research.
  • 1.0K
  • 19 Oct 2022
Topic Review
Implications of Gauge-Free Extended Electrodynamics
Recent tests measured an irrotational (curl-free) magnetic vector potential (A) that is contrary to classical electrodynamics (CED). A (irrotational) arises in extended electrodynamics (EED) that is derivable from the Stueckelberg Lagrangian. A (irrotational) implies an irrotational (gradient-driven) electrical current density, J. Consequently, EED is gauge-free and provably unique. EED predicts a scalar field that equals the quantity usually set to zero as the Lorenz gauge, making A and the scalar potential (F) independent and physically-measureable fields. EED predicts a scalar-longitudinal wave (SLW) that has an electric field along the direction of propagation together with the scalar field, carrying both energy and momentum. EED also predicts the scalar wave (SW) that carries energy without momentum.
  • 1.0K
  • 01 May 2021
Topic Review
Electricity Meter
thumb|North American domestic analogue electricity meter. thumb|Electricity meter with transparent plastic case (Israel) thumb|North American domestic electronic electricity meter An electricity meter, electric meter, electrical meter, or energy meter is a device that measures the amount of electric energy consumed by a residence, a business, or an electrically powered device. Electric utilities use electric meters installed at customers' premises for billing and monitoring purposes. They are typically calibrated in billing units, the most common one being the kilowatt hour (kWh). They are usually read once each billing period. When energy savings during certain periods are desired, some meters may measure demand, the maximum use of power in some interval. "Time of day" metering allows electric rates to be changed during a day, to record usage during peak high-cost periods and off-peak, lower-cost, periods. Also, in some areas meters have relays for demand response load shedding during peak load periods.
  • 988
  • 27 Oct 2022
Topic Review
Electro-gyration
The electrogyration effect is the spatial dispersion phenomenon, that consists in the change of optical activity (gyration) of crystals by a constant or time-varying electric field. Being a spatial dispersion effect, the induced optical activity exhibit different behavior under the operation of wave vector reversal, when compared with the Faraday effect: the optical activity increment associated with the electrogyration effect changes its sign under that operation, contrary to the Faraday effect. Formally, it is a special case of gyroelectromagnetism obtained when the magnetic permeability tensor is diagonal. 
  • 957
  • 05 Dec 2022
Topic Review
«Hadron-M» Complex Installation
“Hadron-M complex installation”, which included an ionization-neutron calorimeter with an area of 55 m2 and an absorber thickness of 1244 g/cm2 (out of eight rows of ionization chambers), one row of neutron detectors and two shower systems of scintillation detectors. The effective area of the “Hadron-M” complex installation was about 30,000 m2.
  • 868
  • 27 Feb 2023
Topic Review
Solid State Ionics
Solid-state ionics is the study of ionic-electronic mixed conductor and fully ionic conductors (solid electrolytes) and their uses. Some materials that fall into this category include inorganic crystalline and polycrystalline solids, ceramics, glasses, polymers, and composites. Solid-state ionic devices, such as solid oxide fuel cells, can be much more reliable and long-lasting, especially under harsh conditions, than comparable devices with fluid electrolytes. The field of solid-state ionics was first developed in Europe, starting with the work of Michael Faraday on solid electrolytes Ag2S and PbF2 in 1834. Fundamental contributions were later made by Walther Nernst, who derived the Nernst equation and detected ionic conduction in heterovalently doped zirconia, which he applied in his Nernst lamp. Another major step forward was the characterization of silver iodide in 1914. Around 1930, the concept of point defects was established by Yakov Frenkel, Walter Schottky and Carl Wagner, including the development of point-defect thermodynamics by Schottky and Wagner; this helped explain ionic and electronic transport in ionic crystals, ion-conducting glasses, polymer electrolytes and nanocomposites. In the late 20th and early 21st centuries, solid-state ionics focused on the synthesis and characterization of novel solid electrolytes and their applications in solid state battery systems, fuel cells and sensors. The term solid state ionics was coined in 1967 by Takehiko Takahashi, but did not become widely used until the 1980s, with the emergence of the journal Solid State Ionics. The first international conference on this topic was held in 1972 in Belgirate, Italy, under the name "Fast Ion Transport in Solids, Solid State Batteries and Devices".
  • 862
  • 31 Oct 2022
Topic Review
D0 Experiment
The DØ experiment (sometimes written D0 experiment, or DZero experiment) consists of a worldwide collaboration of scientists conducting research on the fundamental nature of matter. DØ was one of two major experiments (the other is the CDF experiment) located at the world's second highest-energy accelerator, the Tevatron Collider at the Fermilab in Batavia, Illinois, USA. The research is focused on precise studies of interactions of protons and antiprotons at the highest available energies. It involves an intense search for subatomic clues that reveal the character of the building blocks of the universe.
  • 783
  • 11 Oct 2022
Topic Review
Protein Film Voltammetry
In electrochemistry, protein film voltammetry (or protein film electrochemistry, or direct electrochemistry of proteins) is a technique for examining the behavior of proteins immobilized (either adsorbed or covalently attached) on an electrode. The technique is applicable to proteins and enzymes that engage in electron transfer reactions and it is part of the methods available to study enzyme kinetics. Provided that it makes suitable contact with the electrode surface (electron transfer between the electrode and the protein is direct) and provided that it is not denatured, the protein can be fruitfully interrogated by monitoring current as a function of electrode potential and other experimental parameters. Various electrode materials can be used. Special electrode designs are required to address membrane-bound proteins.
  • 725
  • 02 Dec 2022
Topic Review
Three-Phase
In electrical engineering, three-phase electric power systems have at least three conductors carrying alternating current voltages that are offset in time by one-third of the period. A three-phase system may be arranged in delta (∆) or star (Y) (also denoted as wye in some areas). A wye system allows the use of two different voltages from all three phases, such as a 230/400 V system which provides 230 V between the neutral (centre hub) and any one of the phases, and 400 V across any two phases. A delta system arrangement only provides one voltage magnitude, but it has a greater redundancy as it may continue to operate normally with one of the three supply windings offline, albeit at 57.7% of total capacity. Harmonic current in the neutral may become very large if nonlinear loads are connected.
  • 720
  • 17 Oct 2022
Topic Review
Biological Photovoltaics
Biological photovoltaics (BPV) is an energy-generating technology which uses oxygenic photoautotrophic organisms, or fractions thereof, to harvest light energy and produce electrical power. Biological photovoltaic devices are a type of biological electrochemical system, or microbial fuel cell, and are sometimes also called photo-microbial fuel cells or “living solar cells”. In a biological photovoltaic system, electrons generated by photolysis of water are transferred to an anode. A relatively high-potential reaction takes place at the cathode, and the resulting potential difference drives current through an external circuit to do useful work. It is hoped that using a living organism (which is capable of self-assembly and self-repair) as the light harvesting material, will make biological photovoltaics a cost-effective alternative to synthetic light-energy-transduction technologies such as silicon-based photovoltaics.
  • 680
  • 17 Oct 2022
Topic Review
Electrochemistry
Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential difference, as a measurable and quantitative phenomenon, and identifiable chemical change, with the potential difference as an outcome of a particular chemical change, or vice versa. These reactions involve electrons moving via an electronically-conducting phase (typically an external electrical circuit, but not necessarily, as in electroless plating) between electrodes separated by an ionically conducting and electronically insulating electrolyte (or ionic species in a solution). When a chemical reaction is driven by an electrical potential difference, as in electrolysis, or if a potential difference results from a chemical reaction as in a battery or fuel cell, it is called an electrochemical reaction. Unlike in other chemical reactions, in electrochemical reactions electrons are not transferred directly between atoms, ions, or molecules, but via the aforementioned electronically-conducting circuit. This phenomenon is what distinguishes an electrochemical reaction from a conventional chemical reaction.
  • 678
  • 14 Oct 2022
Topic Review
Water-Based Liquid Scintillators
Monolithic optical detectors, either water–Cherenkov detectors or liquid scintillator detectors, are a well-established technique in neutrino physics. Using water-based liquid scintillators (WbLS) is an approach that exploits Cherenkov and scintillation signals simultaneously; i.e., water is loaded with 1% to 10% liquid scintillator. 
  • 639
  • 04 Jan 2023
Topic Review
Sterile Neutrinos with Neutrino Telescopes
Searches for light sterile neutrinos are motivated by the unexpected observation of an electron neutrino appearance in short-baseline experiments, such as the Liquid Scintillator Neutrino Detector (LSND) and the Mini Booster Neutrino Experiment (MiniBooNE). In light of these unexpected results, a campaign using natural and anthropogenic sources to find the light (mass-squared-difference around 1 eV2) sterile neutrinos is underway. Among the natural sources, atmospheric neutrinos provide a unique gateway to search for sterile neutrinos due to the broad range of baseline-to-energy ratios, L/E, and the presence of significant matter effects. Since the atmospheric neutrino flux rapidly falls with energy, studying its highest energy component requires gigaton-scale neutrino detectors. These detectors—often known as neutrino telescopes since they are designed to observe tiny astrophysical neutrino fluxes—have been used to perform searches for light sterile neutrinos, and researchers have found no significant signal to date. 
  • 633
  • 29 Nov 2021
Topic Review
Standard Electrode Potential
In electrochemistry, standard electrode potential [math]\displaystyle{ E^\ominus }[/math], or [math]\displaystyle{ E^\ominus_{red} }[/math], is a measure of the reducing power of any element or compound. The IUPAC "Gold Book" defines it as: "the value of the standard emf (electromotive force) of a cell in which molecular hydrogen under standard pressure is oxidized to solvated protons at the left-hand electrode".
  • 617
  • 06 Oct 2022
Topic Review
Public Utility Holding Company Act of 1935
The Public Utility Holding Company Act of 1935 (PUHCA), also known as the Wheeler-Rayburn Act, was a US federal law giving the Securities and Exchange Commission authority to regulate, license, and break up electric utility holding companies. It limited holding company operations to a single state, thus subjecting them to effective state regulation. It also broke up any holding companies with more than two tiers, forcing divestitures so that each became a single integrated system serving a limited geographic area. Another purpose of the PUHCA was to keep utility holding companies engaged in regulated businesses from also engaging in unregulated businesses. The act was based on the conclusions and recommendations of the 1928-35 Federal Trade Commission investigation of the electric industry. On March 12, 1935, President Franklin D. Roosevelt released a report he commissioned by the National Power Policy Committee. This report became the template for the PUHCA. The political battle over its passage was one of the bitterest of the New Deal, and was followed by eleven years of legal appeals by holding companies led by the Electric Bond and Share Company, which finally completed its breakup in 1961. On August 26, 1935, President Franklin D. Roosevelt signed the bill into law. The Energy Policy Act of 2005 repealed the PUHCA.
  • 591
  • 18 Nov 2022
Topic Review
Marchywka Effect
The Marchywka effect refers to electrochemical cleaning of diamond using an electric field induced with remote electrodes.
  • 585
  • 25 Oct 2022
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