Porous mediumIn materials science, a porous medium or a porous material is a material containing pores (voids). The skeletal portion of the material is often called the "matrix" or "frame". The pores are typically filled with a fluid (liquid or gas). The skeletal material is usually a solid, but structures like foams are often also usefully analyzed using concept of porous media. A porous medium is most often characterised by its porosity. Other properties of the medium (e.g.
CooperativeA cooperative (also known as co-operative, co-op, or coop) is "an autonomous association of persons united voluntarily to meet their common economic, social and cultural needs and aspirations through a jointly owned and democratically-controlled enterprise". Cooperatives are democratically controlled by their members, with each member having one vote in electing the board of directors.
MechanosynthesisMechanosynthesis is a term for hypothetical chemical syntheses in which reaction outcomes are determined by the use of mechanical constraints to direct reactive molecules to specific molecular sites. There are presently no non-biological chemical syntheses which achieve this aim. Some atomic placement has been achieved with scanning tunnelling microscopes. In conventional chemical synthesis or chemosynthesis, reactive molecules encounter one another through random thermal motion in a liquid or vapor.
Organotin chemistryOrganotin chemistry is the scientific study of the synthesis and properties of organotin compounds or stannanes, which are organometallic compounds containing tin carbon bonds. The first organotin compound was diethyltin diiodide (), discovered by Edward Frankland in 1849. The area grew rapidly in the 1900s, especially after the discovery of the Grignard reagents, which are useful for producing Sn–C bonds. The area remains rich with many applications in industry and continuing activity in the research laboratory.
Workers' self-managementWorkers' self-management, also referred to as labor management and organizational self-management, is a form of organizational management based on self-directed work processes on the part of an organization's workforce. Self-management is a defining characteristic of socialism, with proposals for self-management having appeared many times throughout the history of the socialist movement, advocated variously by democratic, libertarian and market socialists as well as anarchists and communists.
Polyphenylene sulfidePolyphenylene sulfide (PPS) is an organic polymer consisting of aromatic rings linked by sulfides. Synthetic fiber and textiles derived from this polymer resist chemical and thermal attack. PPS is used in filter fabric for coal boilers, papermaking felts, electrical insulation, film capacitors, specialty membranes, gaskets, and packings. PPS is the precursor to a conductive polymer of the semi-flexible rod polymer family. The PPS, which is otherwise insulating, can be converted to the semiconducting form by oxidation or use of dopants.
KeteneIn organic chemistry, a ketene is an organic compound of the form , where R and R' are two arbitrary monovalent chemical groups (or two separate substitution sites in the same molecule). The name may also refer to the specific compound ethenone , the simplest ketene. Although they are highly useful, most ketenes are unstable. When used as reagents in a chemical procedure, they are typically generated when needed, and consumed as soon as (or while) they are produced. Ketenes were first studied as a class by Hermann Staudinger before 1905.