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ⓘ Matter




                                               

Matter

In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic particles, and in everyday as well as scientific usage, "matter" generally includes atoms and anything made up of them, and any particles that act as if they have both rest mass and volume. However it does not include massless particles such as photons, or other energy phenomena or waves such as light or sound. Matter exists in various states. These include ...

                                               

Colloid vibration current

Colloid vibration current is an electroacoustic phenomenon that arises when ultrasound propagates through a fluid that contains ions and either solid particles or emulsion droplets. The pressure gradient in an ultrasonic wave moves particles relative to the fluid. This motion disturbs the double layer that exists at the particle-fluid interface. The picture illustrates the mechanism of this distortion. Practically all particles in fluids carry a surface charge. This surface charge is screened with an equally charged diffuse layer; this structure is called the double layer. Ions of the diff ...

                                               

Debris

Debris is rubble, wreckage, ruins, litter and discarded garbage/refuse/trash, scattered remains of something destroyed, discarded, or as in geology, large rock fragments left by a melting glacier etc. Depending on context, debris can refer to a number of different things. The first apparent use of the French word in English is in a 1701 description of the army of Prince Rupert upon its retreat from a battle with the army of Oliver Cromwell, in England.

                                               

Double layer (surface science)

A double layer is a structure that appears on the surface of an object when it is exposed to a fluid. The object might be a solid particle, a gas bubble, a liquid droplet, or a porous body. The DL refers to two parallel layers of charge surrounding the object. The first layer, the surface charge, consists of ions adsorbed onto the object due to chemical interactions. The second layer is composed of ions attracted to the surface charge via the Coulomb force, electrically screening the first layer. This second layer is loosely associated with the object. It is made of free ions that move in ...

                                               

Dukhin number

The Dukhin number is a dimensionless quantity that characterizes the contribution of the surface conductivity to various electrokinetic and electroacoustic effects, as well as to electrical conductivity and permittivity of fluid heterogeneous systems.

                                               

Electroacoustic phenomena

Electroacoustic phenomena arise when ultrasound propagates through a fluid containing ions. The associated particle motion generates electric signals because ions have electric charge. This coupling between ultrasound and electric field is called electroacoustic phenomena. The fluid might be a simple Newtonian liquid, or complex heterogeneous dispersion, emulsion or even a porous body. There are several different electroacoustic effects depending on the nature of the fluid., Electric sonic amplitude ESA, the inverse of the CVI effect, in which an acoustic field arises when an electric fiel ...

                                               

Field effect (chemistry)

A field effect is the polarization of a molecule through space. The effect is a result of an electric field produced by charge localization in a molecule. This field, which is substituent and conformation dependent, can influence structure and reactivity by manipulating the location of electron density in bonds and/or the overall molecule. The polarization of a molecule through its bonds is a separate phenomenon known as induction. Field effects are relatively weak, and diminish rapidly with distance, but have still been found to alter molecular properties such as acidity.

                                               

Hardness

Hardness is a measure of the resistance to localized plastic deformation induced by either mechanical indentation or abrasion. Some materials are harder than others. Macroscopic hardness is generally characterized by strong intermolecular bonds, but the behavior of solid materials under force is complex; therefore, there are different measurements of hardness: scratch hardness, indentation hardness, and rebound hardness. Hardness is dependent on ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity. Common examples of hard matter are ceramics ...

                                               

Interface (matter)

In the physical sciences, an interface is the boundary between two spatial regions occupied by different matter, or by matter in different physical states. The interface between matter and air, or matter and vacuum, is called a surface, and studied in surface science. In thermal equilibrium, the regions in contact are called phases, and the interface is called a phase boundary. An example for an interface out of equilibrium is the grain boundary in polycrystalline matter. The importance of the interface depends on the type of system: the bigger the quotient area/volume, the greater the eff ...

                                               

Ion vibration current

The ion vibration current and the associated ion vibration potential is an electric signal that arises when an acoustic wave propagates through a homogeneous fluid. Historically, the IVI was the first known electroacoustic phenomenon. It was predicted by Peter Debye in 1933. When a longitudinal sound wave travels through a solvent, the associated pressure gradients push the fluid particles back and forth, and it is easy in practice to create such accelerations that measure thousands or millions of gs. If a solute molecule is more dense or less dense than the surrounding liquid, then in thi ...

                                               

Material

A material is a substance or mixture of substances that constitutes an object. Materials can be pure or impure, living or non-living matter. Materials can be classified based on their physical and chemical properties, or on their geological origin or biological function. Materials science is the study of materials and their applications. Raw materials can be processed in different ways to influence their properties, by purification, shaping or the introduction of other materials. New materials can be produced from raw materials by synthesis. In industry, materials are inputs to manufacturi ...

                                               

Matter wave

Matter waves are a central part of the theory of quantum mechanics, being an example of wave–particle duality. All matter exhibits wave-like behavior. For example, a beam of electrons can be diffracted just like a beam of light or a water wave. In most cases, however, the wavelength is too small as to have a practical impact on day-to-day activities. Hence in our day-to-day lives with objects the size of tennis balls and people, matter waves are not relevant. The concept that matter behaves like a wave was proposed by Louis de Broglie in 1924. It is also referred to as the de Broglie hypot ...

                                               

Moisture expansion

Moisture expansion is the tendency of matter to change in volume in response to a change in moisture content. The macroscopic effect is similar to that of thermal expansion but the microscopic causes are very different. Moisture expansion is caused by hygroscopy.

                                               

Molecule

A molecule is an electrically neutral group of two or more atoms held together by chemical bonds. Molecules are distinguished from ions by their lack of electrical charge. However, in quantum physics, organic chemistry, and biochemistry, the term molecule is often used less strictly, also being applied to polyatomic ions. In the kinetic theory of gases, the term molecule is often used for any gaseous particle regardless of its composition. According to this definition, noble gas atoms are considered molecules as they are monatomic molecules. A molecule may be homonuclear, that is, it consi ...

                                               

Particle

In the physical sciences, a particle is a small localized object or entity to which can be ascribed several physical or chemical properties such as volume, density or mass. They vary greatly in size or quantity, from subatomic particles like the electron, to microscopic particles like atoms and molecules, to macroscopic particles like powders and other granular materials. Particles can also be used to create scientific models of even larger objects depending on their density, such as humans moving in a crowd or celestial bodies in motion. The term particle is rather general in meaning, and ...

                                               

Streaming vibration current

The streaming vibration current and the associated streaming vibration potential is an electric signal that arises when an acoustic wave propagates through a porous body in which the pores are filled with fluid. Streaming vibration current was experimentally observed in 1948 by M. Williams. A theoretical model was developed some 30 years later by Dukhin and coworkers. This effect opens another possibility for characterizing the electric properties of the surfaces in porous bodies.

                                               

Surface conductivity

Surface conductivity is an additional conductivity of an electrolyte in the vicinity of the charged interfaces. Surface and volume conductivity of liquids correspond to the electrically driven motion of ions in an electric field. A layer of counter ions of the opposite polarity to the surface charge exists close to the interface. It is formed due to attraction of counter-ions by the surface charges. This layer of higher ionic concentration is a part of the interfacial double layer. The concentration of the ions in this layer is higher as compared to the ionic strength of the liquid bulk. T ...

                                               

Zeta potential titration

Zeta potential titration is a titration of heterogeneous systems, for example colloids and emulsions. Solids in such systems have very high surface area. This type of titration is used to study the zeta potential of these surfaces under different conditions. Details of zeta potential definition and measuring techniques can be found in the International Standard.

                                     

ⓘ Matter

  • The Matter of Britain is the body of Medieval literature and legendary material associated with Great Britain and Brittany, and the legendary kings and
  • Hot dark matter HDM is a theoretical form of dark matter which consists of particles that travel with ultrarelativistic velocities. Dark matter is a form
  • Matter is the substance of which objects are made. Matter or Matters may also refer to: Matter philosophy a concept in philosophy Matter Valley, a
  • Blue Lives Matter is a countermovement in the United States advocating that those who are prosecuted and convicted of killing law enforcement officers
  • Organic matter organic material, or natural organic matter refers to the large source of carbon - based compounds found within natural and engineered
  • Mind over matter is a popular phrase with paranormal, spiritual, and philosophical uses. Mind over Matter may also refer to: Mind over Matter band an
  • cosmology scalar field dark matter is a classical, minimally coupled, scalar field postulated to account for the inferred dark matter The universe may be accelerating

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