In chemistry, sigma bonds (s bonds) are the strongest type of covalent chemical bond. They are formed by head-on overlapping between atomic orbitals. Sigma bonding is most simply defined for diatomic molecules using the language and tools of symmetry groups. In this formal approach, a s-bond is symmetrical with respect to rotation about the bond […]
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Sigma bond
M13 bacteriophage
M13 is one of the Ff phages (fd and f1 are others), a member of the family filamentous bacteriophage (inovirus). Ff phages are composed of circular single-stranded DNA (ssDNA), which in the case of the m13 phage is 6407 nucleotides long and is encapsulated in approximately 2700 copies of the major coat protein p8, and […]
Lev Navrozov
Lev Andreevich Navrozov (Russian: LEV ANDREEVIC NAVROZOV; 26 November 1928 - 22 January 2017) was a Russian author, historian and polemicist, born in Moscow and father of poet Andrei Navrozov. A leading translator of Russian texts into English under the Soviet regime, Navrozov emigrated to the United States in 1972, where he published a best-selling […]
Van Hove singularity
A Van Hove singularity is a singularity (non-smooth point) in the density of states (DOS) of a crystalline solid. The wavevectors at which Van Hove singularities occur are often referred to as critical points of the Brillouin zone. For three-dimensional crystals, they take the form of kinks (where the density of states is not differentiable). […]
Textile performance
Textile performance, also known as fitness for purpose, is a textile's capacity to withstand various conditions, environments, and hazards, qualifying it for particular uses. The performance of textile products influences their appearance, comfort, durability, and protection. Different textile applications (automotive, clothing, sleepwear, workwear, sportswear, upholstery, and PPE) require a different set of performance parameters. As […]
Vacancy defect
In crystallography, a vacancy is a type of point defect in a crystal where an atom is missing from one of the lattice sites. Crystals inherently possess imperfections, sometimes referred to as crystallographic defects. Vacancies occur naturally in all crystalline materials. At any given temperature, up to the melting point of the material, there is […]
Interfacial thermal resistance
Image by/from ScottTParker Interfacial thermal resistance, also known as thermal boundary resistance, or Kapitza resistance, is a measure of resistance to thermal flow at the interface between two materials. While these terms may be used interchangeably, Kapitza resistance technically refers to an atomically perfect, flat interface whereas thermal boundary resistance is a more broad term. […]
Upcycling
Upcycling, also known as creative reuse, is the process of transforming by-products, waste materials, useless, or unwanted products into new materials or products perceived to be of greater quality, such as artistic value or environmental value. Upcycling is the opposite of downcycling, which is the other part of the recycling process. Downcycling involves converting materials […]
Inkjet printing
Image by/from Somebody in the WWW at English Wikipedia Inkjet printing is a type of computer printing that recreates a digital image by propelling droplets of ink onto paper and plastic substrates. Inkjet printers were the most commonly used type of printer in 2008, and range from small inexpensive consumer models to expensive professional machines. […]
Force-sensing resistor
A force-sensing resistor is a material whose resistance changes when a force, pressure or mechanical stress is applied. They are also known as force-sensitive resistor and are sometimes referred to by the initialism FSR. The technology of force-sensing resistors was invented and patented in 1977 by Franklin Eventoff. In 1985 Eventoff founded Interlink Electronics, a […]