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ISO 80000-9
ISO/IEC 80000, ''Quantities and units'', is an international standard describing the International System of Quantities (ISQ). It was developed and promulgated jointly by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). It serves as a style guide for using physical quantities and units of measurement, formulas involving them, and their corresponding units, in scientific and educational documents for worldwide use. The ISO/IEC 80000 family of standards was completed with the publication of the first edition of Part 1 in November 2009. Overview By 2021, ISO/IEC 80000 comprised 13 parts, two of which (parts 6 and 13) were developed by IEC and the remaining 11 were developed by ISO, with a further three parts (15, 16 and, 17) under development. Part 14 was withdrawn. Subject areas By 2021 the 80000 standard had 13 published parts. A description of each part is available online, with the complete parts for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Standard
An international standard is a technical standard developed by one or more international standards organizations. International standards are available for consideration and use worldwide. The most prominent such organization is the International Organization for Standardization (ISO). Other prominent international standards organizations including the International Telecommunication Union (ITU) and the International Electrotechnical Commission (IEC). Together, these three organizations have formed the World Standards Cooperation alliance. Purpose International standards can be applied directly or adapted to meet local conditions. When adopted, they lead to the creation of national standards that are either equivalent to or largely align with the international standards in technical content, though they may have: (i) editorial variations, such as differences in appearance, the use of symbols, measurement units, or the choice of a point over a comma as the decimal marker, and (ii) va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermodynamics
Thermodynamics is a branch of physics that deals with heat, Work (thermodynamics), work, and temperature, and their relation to energy, entropy, and the physical properties of matter and radiation. The behavior of these quantities is governed by the four laws of thermodynamics, which convey a quantitative description using measurable macroscopic physical quantity, physical quantities but may be explained in terms of microscopic constituents by statistical mechanics. Thermodynamics applies to various topics in science and engineering, especially physical chemistry, biochemistry, chemical engineering, and mechanical engineering, as well as other complex fields such as meteorology. Historically, thermodynamics developed out of a desire to increase the thermodynamic efficiency, efficiency of early steam engines, particularly through the work of French physicist Nicolas Léonard Sadi Carnot, Sadi Carnot (1824) who believed that engine efficiency was the key that could help France win ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Physics
Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter. Nuclear physics should not be confused with atomic physics, which studies the atom as a whole, including its electrons. Discoveries in nuclear physics have led to applications in many fields such as nuclear power, nuclear weapons, nuclear medicine and magnetic resonance imaging, industrial and agricultural isotopes, ion implantation in materials engineering, and radiocarbon dating in geology and archaeology. Such applications are studied in the field of nuclear engineering. Particle physics evolved out of nuclear physics and the two fields are typically taught in close association. Nuclear astrophysics, the application of nuclear physics to astrophysics, is crucial in explaining the inner workings of stars and the origin of the chemical elements. History The history of nuclear physics as a discipline ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Physics
Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. Atomic physics typically refers to the study of atomic structure and the interaction between atoms. It is primarily concerned with the way in which electrons are arranged around the nucleus and the processes by which these arrangements change. This comprises ions, neutral atoms and, unless otherwise stated, it can be assumed that the term ''atom'' includes ions. The term ''atomic physics'' can be associated with nuclear power and nuclear weapons, due to the synonymous use of ''atomic'' and ''nuclear'' in standard English. Physicists distinguish between atomic physics—which deals with the atom as a system consisting of a nucleus and electrons—and nuclear physics, which studies nuclear reactions and special properties of atomic nuclei. As with many scientific fields, strict delineation can be highly contrived and atomic physics is often considered in the w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO 31-8
ISO 31-8 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to ''physical chemistry and molecular physics''. Quantities and units Notes In the tables of quantities and their units, the ISO 31-8 standard shows symbols for substances as subscripts (e.g., ''c''B, ''w''B, ''p''B). It also notes that it is generally advisable to put symbols for substances and their states in parentheses on the same line, as in ''c''(H2SO4). Normative annexes Annex A: Names and symbols of the chemical elements This annex contains a list of elements by atomic number, giving the names and standard symbols of the chemical elements from atomic number 1 (hydrogen, H) to 109 ( unnilennium, Une). The list given in ISO 31-8:1992 was quoted from the 1998 IUPAC "Green Book" Quantities, Units and Symbols in Physical Chemistry and adds in some cases in parentheses the Latin name for information, where the standard symbol has no relation to the English ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Physics
Molecular physics is the study of the physical properties of molecules and molecular dynamics. The field overlaps significantly with physical chemistry, chemical physics, and quantum chemistry. It is often considered as a sub-field of atomic, molecular, and optical physics. Research groups studying molecular physics are typically designated as one of these other fields. Molecular physics addresses phenomena due to both molecular structure and individual atomic processes within molecules. Like atomic physics, it relies on a combination of classical and quantum mechanics to describe interactions between electromagnetic radiation and matter. Experiments in the field often rely heavily on techniques borrowed from atomic physics, such as spectroscopy and scattering. Molecular structure In a molecule, both the electrons and nuclei experience similar-scale forces from the Coulomb interaction. However, the nuclei remain at nearly fixed locations in the molecule while the electrons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Chemistry
Physical chemistry is the study of macroscopic and microscopic phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical mechanics, analytical dynamics and chemical equilibria. Physical chemistry, in contrast to chemical physics, is predominantly (but not always) a supra-molecular science, as the majority of the principles on which it was founded relate to the bulk rather than the molecular or atomic structure alone (for example, chemical equilibrium and colloids). Some of the relationships that physical chemistry strives to understand include the effects of: # Intermolecular forces that act upon the physical properties of materials ( plasticity, tensile strength, surface tension in liquids). # Reaction kinetics on the rate of a reaction. # The identity of ions and the electrical conductivity of materials. # Surface science and electrochemistry of cell m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO 31-7
ISO 31-7 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to acoustics Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician .... It is superseded by ISO 80000-8. Its definitions include: References Acoustics #00031-07 {{Standard-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acoustics
Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics technology may be called an Acoustical engineering, acoustical engineer. The application of acoustics is present in almost all aspects of modern society with the most obvious being the audio and noise control industries. Hearing (sense), Hearing is one of the most crucial means of survival in the animal world and speech is one of the most distinctive characteristics of human development and culture. Accordingly, the science of acoustics spreads across many facets of human society—music, medicine, architecture, industrial production, warfare and more. Likewise, animal species such as songbirds and frogs use sound and hearing as a key element of mating rituals or for marking territories. Art, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO 31-6
ISO 31-6 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to ''light and related electromagnetic radiation In physics, electromagnetic radiation (EMR) is a self-propagating wave of the electromagnetic field that carries momentum and radiant energy through space. It encompasses a broad spectrum, classified by frequency or its inverse, wavelength ...s''. It is superseded by ISO 80000-7. ISO 31-6 was initially published in 1980, and amended in 1985. It received a revision in 1992, which was amended in 1998. The standard was ultimately withdrawn in 2008, when it was replaced by ISO 80000-7. Definitions The definitions of ISO 31-6, as defined in 1980, included: Notes References #00031-06 {{Standard-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiation
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a material medium. This includes: * ''electromagnetic radiation'' consisting of photons, such as radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and Gamma ray, gamma radiation (γ) * ''particle radiation'' consisting of particles of non-zero rest energy, such as alpha radiation (α), beta radiation (β), proton radiation and neutron radiation * ''acoustics, acoustic radiation'', such as ultrasound, sound, and seismic waves, all dependent on a physical transmission medium * ''gravitational radiation'', in the form of gravitational waves, ripples in spacetime Radiation is often categorized as either ''ionizing radiation, ionizing'' or ''non-ionizing radiation, non-ionizing'' depending on the energy of the radiated particles. Ionizing radiation carries more than 10 electron volt, electron volts (eV), which is enough to ionize atoms and molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light
Light, visible light, or visible radiation is electromagnetic radiation that can be visual perception, perceived by the human eye. Visible light spans the visible spectrum and is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequency, frequencies of 750–420 terahertz (unit), terahertz. The visible band sits adjacent to the infrared (with longer wavelengths and lower frequencies) and the ultraviolet (with shorter wavelengths and higher frequencies), called collectively ''optical radiation''. In physics, the term "light" may refer more broadly to electromagnetic radiation of any wavelength, whether visible or not. In this sense, gamma rays, X-rays, microwaves and radio waves are also light. The primary properties of light are intensity (physics), intensity, propagation direction, frequency or wavelength spectrum, and polarization (waves), polarization. Its speed of light, speed in vacuum, , is one of the fundamental physi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
