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to originate from radioactivity but, rather, result from processes like those that produce astronomical X-rays, except driven by much more energetic electrons. Photoelectric absorption is the dominant mechanism in organic materials for photon energies below 100 keV, typical of classical X-ray tube originated X-rays. At...	{ "page_id": 202522, "title": "Ionizing radiation" }
electrical charge and thus often do not directly cause ionization in a single step or interaction with matter. However, fast neutrons will interact with the protons in hydrogen via linear energy transfer, energy that a particle transfers to the material it is moving through. This mechanism scatters the nuclei of the ma...	{ "page_id": 202522, "title": "Ionizing radiation" }
nuclear reactor while operating. For the best shielding of neutrons, hydrocarbons that have an abundance of hydrogen are used. In fissile materials, secondary neutrons may produce nuclear chain reactions, causing a larger amount of ionization from the daughter products of fission. Outside the nucleus, free neutrons are...	{ "page_id": 202522, "title": "Ionizing radiation" }
The glow can be observed, e.g., during criticality accidents, around mushroom clouds shortly after a nuclear explosion, or the inside of a damaged nuclear reactor like during the Chernobyl disaster. Monatomic fluids, e.g. molten sodium, have no chemical bonds to break and no crystal lattice to disturb, so they are immu...	{ "page_id": 202522, "title": "Ionizing radiation" }
reproductive (germ) cells. The most common impact is stochastic radiation-induced cancer with a latent period of years or decades after exposure. For example, ionizing radiation is one cause of chronic myelogenous leukemia, although most people with CML have not been exposed to radiation. The mechanism by which this oc...	{ "page_id": 202522, "title": "Ionizing radiation" }
damage, although they do not cause sunburn (erythema). Like ionization-damage, all these effects in skin are beyond those produced by simple thermal effects. == Measurement of radiation == The table below shows radiation and dose quantities in SI and non-SI units. == Uses of radiation == Ionizing radiation has many ind...	{ "page_id": 202522, "title": "Ionizing radiation" }
3 mSv (0.3 rem) per year, 80% of which comes from nature. The remaining 20% results from exposure to human-made radiation sources, mainly medical imaging. Average human-made exposure is much higher in developed countries, mostly due to CT scans and nuclear medicine. Natural background radiation comes from five primary ...	{ "page_id": 202522, "title": "Ionizing radiation" }
radiation danger. Radiation danger from background radiation may be a serious threat but is more likely a small overall risk compared to all other factors in the environment. ==== Cosmic radiation ==== The Earth, and all living things on it, are constantly bombarded by radiation from outside the Solar System. This cosm...	{ "page_id": 202522, "title": "Ionizing radiation" }
major radionuclides of concern for terrestrial radiation are isotopes of potassium, uranium, and thorium. Each of these sources has been decreasing in activity since the formation of the Earth. ==== Internal radiation sources ==== All earthly materials that are the building blocks of life contain a radioactive componen...	{ "page_id": 202522, "title": "Ionizing radiation" }
or lined with lead. There are special plastic shields that stop beta particles, and air will stop most alpha particles. The effectiveness of a material in shielding radiation is determined by its half-value thicknesses, the thickness of material that reduces the radiation by half. This value is a function of the materi...	{ "page_id": 202522, "title": "Ionizing radiation" }
The ICRP recommends limiting artificial irradiation. For occupational exposure, the limit is 50 mSv in a single year with a maximum of 100 mSv in a consecutive five-year period. The radiation exposure of these individuals is carefully monitored with the use of dosimeters and other radiological protection instruments wh...	{ "page_id": 202522, "title": "Ionizing radiation" }
no-threshold model (LNT). The International Commission on Radiological Protection recommends limiting artificial irradiation to the public to an average of 1 mSv (0.001 Sv) of effective dose per year, not including medical and occupational exposures. In a nuclear war, gamma rays from both the initial weapon explosion a...	{ "page_id": 202522, "title": "Ionizing radiation" }
more than 0.5 mSv per month. Information originally based on Fundamentals of Aerospace Medicine published in 2008. === Radiation hazard warning signs === Hazardous levels of ionizing radiation are signified by the trefoil sign on a yellow background. These are usually posted at the boundary of a radiation controlled ar...	{ "page_id": 202522, "title": "Ionizing radiation" }
In statistics, the k-nearest neighbors algorithm (k-NN) is a non-parametric supervised learning method. It was first developed by Evelyn Fix and Joseph Hodges in 1951, and later expanded by Thomas Cover. Most often, it is used for classification, as a k-NN classifier, the output of which is a class membership. An objec...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
function is only approximated locally and all computation is deferred until function evaluation. Since this algorithm relies on distance, if the features represent different physical units or come in vastly different scales, then feature-wise normalizing of the training data can greatly improve its accuracy. == Statist...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
query point. A commonly used distance metric for continuous variables is Euclidean distance. For discrete variables, such as for text classification, another metric can be used, such as the overlap metric (or Hamming distance). In the context of gene expression microarray data, for example, k-NN has been employed with ...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
the class of the closest training sample (i.e. when k = 1) is called the nearest neighbor algorithm. The accuracy of the k-NN algorithm can be severely degraded by the presence of noisy or irrelevant features, or if the feature scales are not consistent with their importance. Much research effort has been put into sele...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
the strong consistency of weighted nearest neighbour classifiers also holds. Let C n w n n {\displaystyle C_{n}^{wnn}} denote the weighted nearest classifier with weights { w n i } i = 1 n {\displaystyle \{w_{ni}\}_{i=1}^{n}} . Subject to regularity conditions, which in asymptotic theory are conditional variables which...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
for i = k ∗ + 1 , … , n {\displaystyle i=k^{*}+1,\dots ,n} . With optimal weights the dominant term in the asymptotic expansion of the excess risk is O ( n − 4 d + 4 ) {\displaystyle {\mathcal {O}}(n^{-{\frac {4}{d+4}}})} . Similar results are true when using a bagged nearest neighbour classifier. == Properties == k-NN...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
by some distribution. For M = 2 {\displaystyle M=2} and as the Bayesian error rate R ∗ {\displaystyle R^{*}} approaches zero, this limit reduces to "not more than twice the Bayesian error rate". == Error rates == There are many results on the error rate of the k nearest neighbour classifiers. The k-nearest neighbour cl...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
a new metric or pseudo-metric. == Feature extraction == When the input data to an algorithm is too large to be processed and it is suspected to be redundant (e.g. the same measurement in both feet and meters) then the input data will be transformed into a reduced representation set of features (also named features vect...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
pre-processing step, followed by clustering by k-NN on feature vectors in reduced-dimension space. This process is also called low-dimensional embedding. For very-high-dimensional datasets (e.g. when performing a similarity search on live video streams, DNA data or high-dimensional time series) running a fast approxima...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
analysis. Given two natural numbers, k>r>0, a training example is called a (k,r)NN class-outlier if its k nearest neighbors include more than r examples of other classes. === Condensed Nearest Neighbor for data reduction === Condensed nearest neighbor (CNN, the Hart algorithm) is an algorithm designed to reduce the dat...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
closest to y red point is x' . The border ratio a(x) = ‖x'-y‖ / ‖x-y‖is the attribute of the initial point x. Below is an illustration of CNN in a series of figures. There are three classes (red, green and blue). Fig. 1: initially there are 60 points in each class. Fig. 2 shows the 1NN classification map: each pixel is...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
an inverse distance weighted average with the k-nearest multivariate neighbors. == k-NN outlier == The distance to the kth nearest neighbor can also be seen as a local density estimate and thus is also a popular outlier score in anomaly detection. The larger the distance to the k-NN, the lower the local density, the mo...	{ "page_id": 1775388, "title": "K-nearest neighbors algorithm" }
The Day of Remembrance for All Victims of Chemical Warfare is an annual event held November 30 as a "tribute to the victims of chemical warfare, as well as to reaffirm the commitment of the Organisation for the Prohibition of Chemical Weapons (OPCW) to the elimination of the threat of chemical weapons, thereby promotin...	{ "page_id": 40703774, "title": "Day of Remembrance for All Victims of Chemical Warfare" }
known to possess a sizeable stockpile and Secretary-General Ban Ki-moon noted this in his 2013 speech, condemning the nation for its alleged exploitation of chemical weapons in its ongoing civil war. On September 14, 2013, the United States and Russia announced in Geneva that they reached a deal whereby Syria would rat...	{ "page_id": 40703774, "title": "Day of Remembrance for All Victims of Chemical Warfare" }
The molecular formula C9H11FN2O5 may refer to: Doxifluridine, a second generation nucleoside analog Floxuridine, an antimetabolite oncology drug	{ "page_id": 24319775, "title": "C9H11FN2O5" }
Flash pasteurization, also called "high-temperature short-time" (HTST) processing, is a method of heat pasteurization of perishable beverages like fruit and vegetable juices, beer, wine, and some dairy products such as milk. Compared with other pasteurization processes, it maintains color and flavor better, but some ch...	{ "page_id": 2168608, "title": "Flash pasteurization" }
Dipankar Das Sarma, popularly known as D.D. Sarma, is an Indian scientist and structural chemist, known for his researches in the fields of Solid State Chemistry, Spectroscopy, Condensed Matter Physics, Materials Science, and Nanoscience. He is a former MLS Chair Professor of Physics and Chairman of the Centre for Adva...	{ "page_id": 45094689, "title": "Dipankar Das Sarma" }
of Science. Besides heading the Solid State and Structural Chemistry Unit, he served as a guest professor at the Uppsala University, Sweden, a Distinguished Scientist at the CSIR-Network Institutes of Solar Energy, an honorary professor at the Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru and a di...	{ "page_id": 45094689, "title": "Dipankar Das Sarma" }
and has held the chairs of the Proposal Review Committee of Elettra Synchrotron Centre, Trieste and the Scientific Advisory Committee of the UGC-DAE Consortium for Scientific Research of which he has also served as a member of the governing body and the governing council. D. D. Sarma is a former member of the Scientifi...	{ "page_id": 45094689, "title": "Dipankar Das Sarma" }
in 2009. == Legacy == Dipankar Das Sarma is credited with extensive research on nanomaterials and strongly correlated materials. His contribution is reported in discovering the existence of a new phase in solid state materials through high-energy spectroscopies and theory. His researches have been documented by way of ...	{ "page_id": 45094689, "title": "Dipankar Das Sarma" }
FICCI Award in 2006, TWAS Prize in Physics in 2007, the National Research Award in 2009 and H. K. Firodia Award in 2013. He was honored with the Knight of "The Order of the Star of Italy" in 2014, and an Honorary Doctorate from the Faculty of Science and Technology at Uppsala University in 2015. Sarma, an elected Fello...	{ "page_id": 45094689, "title": "Dipankar Das Sarma" }
Continuum mechanics is a branch of mechanics that deals with the deformation of and transmission of forces through materials modeled as a continuous medium (also called a continuum) rather than as discrete particles. Continuum mechanics deals with deformable bodies, as opposed to rigid bodies. A continuum model assumes...	{ "page_id": 5918, "title": "Continuum mechanics" }
continuous functions, and their evolution can be studied using the mathematics of calculus. Apart from the assumption of continuity, two other independent assumptions are often employed in the study of continuum mechanics. These are homogeneity (assumption of identical properties at all locations) and isotropy (assumpt...	{ "page_id": 5918, "title": "Continuum mechanics" }
the configuration at the initial time, so that x = κ t ( X ) . {\displaystyle \mathbf {x} =\kappa _{t}(\mathbf {X} ).} This function needs to have various properties so that the model makes physical sense. κ t ( ⋅ ) {\displaystyle \kappa _{t}(\cdot )} needs to be: continuous in time, so that the body changes in a way w...	{ "page_id": 5918, "title": "Continuum mechanics" }
mechanical interaction between the parts of the body to either side of the surface (Euler-Cauchy's stress principle). When a body is acted upon by external contact forces, internal contact forces are then transmitted from point to point inside the body to balance their action, according to Newton's third law of motion ...	{ "page_id": 5918, "title": "Continuum mechanics" }
where T ( n ) {\displaystyle \mathbf {T} ^{(\mathbf {n} )}} is the surface traction, also called stress vector, traction, or traction vector. The stress vector is a frame-indifferent vector (see Euler-Cauchy's stress principle). The total contact force on the particular internal surface S {\displaystyle S\,\!} is then ...	{ "page_id": 5918, "title": "Continuum mechanics" }
to be continuous over the entire volume of the body, i.e. acting on every point in it. Body forces are represented by a body force density b ( x , t ) {\displaystyle \mathbf {b} (\mathbf {x} ,t)} (per unit of mass), which is a frame-indifferent vector field. In the case of gravitational forces, the intensity of the for...	{ "page_id": 5918, "title": "Continuum mechanics" }
the volume of the body. Both are important in the analysis of stress for a polarized dielectric solid under the action of an electric field, materials where the molecular structure is taken into consideration (e.g. bones), solids under the action of an external magnetic field, and the dislocation theory of metals. Mate...	{ "page_id": 5918, "title": "Continuum mechanics" }
displacements. Thus, the material body will occupy different configurations at different times so that a particle occupies a series of points in space which describe a path line. There is continuity during motion or deformation of a continuum body in the sense that: The material points forming a closed curve at any ins...	{ "page_id": 5918, "title": "Continuum mechanics" }
obtained are independent of the choice of initial time and reference configuration, κ 0 ( B ) {\displaystyle \kappa _{0}({\mathcal {B}})} . This description is normally used in solid mechanics. In the Lagrangian description, the motion of a continuum body is expressed by the mapping function χ ( ⋅ ) {\displaystyle \chi...	{ "page_id": 5918, "title": "Continuum mechanics" }
the substantial derivative, or comoving derivative, or convective derivative. It can be thought as the rate at which the property changes when measured by an observer traveling with that group of particles. In the Lagrangian description, the material derivative of P i j … {\displaystyle P_{ij\ldots }} is simply the par...	{ "page_id": 5918, "title": "Continuum mechanics" }
P i j … ( ⋅ ) {\displaystyle P_{ij\ldots }(\cdot )} are single-valued and continuous, with continuous derivatives with respect to space and time to whatever order is required, usually to the second or third. === Eulerian description === Continuity allows for the inverse of χ ( ⋅ ) {\displaystyle \chi (\cdot )} to trace...	{ "page_id": 5918, "title": "Continuum mechanics" }
sufficient condition for this inverse function to exist is that the determinant of the Jacobian matrix, often referred to simply as the Jacobian, should be different from zero. Thus, J = \| ∂ χ i ∂ X J \| = \| ∂ x i ∂ X J \| ≠ 0 {\displaystyle J=\left\|{\frac {\partial \chi _{i}}{\partial X_{J}}}\right\|=\left\|{\frac {\parti...	{ "page_id": 5918, "title": "Continuum mechanics" }
} . The second term of the right-hand side is the convective rate of change and expresses the contribution of the particle changing position in space (motion). Continuity in the Eulerian description is expressed by the spatial and temporal continuity and continuous differentiability of the flow velocity field. All phys...	{ "page_id": 5918, "title": "Continuum mechanics" }
J i x i − X J {\displaystyle \mathbf {U} (\mathbf {x} ,t)=\mathbf {b} +\mathbf {x} -\mathbf {X} (\mathbf {x} ,t)\qquad {\text{or}}\qquad U_{J}=b_{J}+\alpha _{Ji}x_{i}-X_{J}\,} where α J i {\displaystyle \alpha _{Ji}} are the direction cosines between the material and spatial coordinate systems with unit vectors E J {\d...	{ "page_id": 5918, "title": "Continuum mechanics" }
( x , t ) = x − X ( x , t ) or U J = δ J i x i − X J {\displaystyle \mathbf {U} (\mathbf {x} ,t)=\mathbf {x} -\mathbf {X} (\mathbf {x} ,t)\qquad {\text{or}}\qquad U_{J}=\delta _{Ji}x_{i}-X_{J}} == Governing equations == Continuum mechanics deals with the behavior of materials that can be approximated as continuous for ...	{ "page_id": 5918, "title": "Continuum mechanics" }
is the location of the same point in the deformed configuration. The deformation gradient is given by F = ∂ x ∂ X = ∇ x . {\displaystyle {\boldsymbol {F}}={\frac {\partial \mathbf {x} }{\partial \mathbf {X} }}=\nabla \mathbf {x} ~.} === Balance laws === Let f ( x , t ) {\displaystyle f(\mathbf {x} ,t)} be a physical qu...	{ "page_id": 5918, "title": "Continuum mechanics" }
,t)~{\text{dV}}~.} The functions f ( x , t ) {\displaystyle f(\mathbf {x} ,t)} , g ( x , t ) {\displaystyle g(\mathbf {x} ,t)} , and h ( x , t ) {\displaystyle h(\mathbf {x} ,t)} can be scalar valued, vector valued, or tensor valued - depending on the physical quantity that the balance equation deals with. If there are...	{ "page_id": 5918, "title": "Continuum mechanics" }
is the particle velocity, v ˙ {\displaystyle {\dot {\mathbf {v} }}} is the material time derivative of v {\displaystyle \mathbf {v} } , σ ( x , t ) {\displaystyle {\boldsymbol {\sigma }}(\mathbf {x} ,t)} is the Cauchy stress tensor, b ( x , t ) {\displaystyle \mathbf {b} (\mathbf {x} ,t)} is the body force density, e (...	{ "page_id": 5918, "title": "Continuum mechanics" }
to the Cauchy stress tensor by P = J σ ⋅ F − T where J = det ( F ) {\displaystyle {\boldsymbol {P}}=J~{\boldsymbol {\sigma }}\cdot {\boldsymbol {F}}^{-T}~{\text{where}}~J=\det({\boldsymbol {F}})} We can alternatively define the nominal stress tensor N {\displaystyle {\boldsymbol {N}}} which is the transpose of the firs...	{ "page_id": 5918, "title": "Continuum mechanics" }
{e} _{i}\otimes \mathbf {e} _{j}=v_{i,j}\mathbf {e} _{i}\otimes \mathbf {e} _{j}~;\\[1ex]{\boldsymbol {\nabla }}\cdot \mathbf {v} &=\sum _{i=1}^{3}{\frac {\partial v_{i}}{\partial x_{i}}}=v_{i,i}~;\\[1ex]{\boldsymbol {\nabla }}\cdot {\boldsymbol {S}}&=\sum _{i,j=1}^{3}{\frac {\partial S_{ij}}{\partial x_{j}}}~\mathbf {...	{ "page_id": 5918, "title": "Continuum mechanics" }
statement concerning the irreversibility of natural processes, especially when energy dissipation is involved. Just like in the balance laws in the previous section, we assume that there is a flux of a quantity, a source of the quantity, and an internal density of the quantity per unit mass. The quantity of interest in...	{ "page_id": 5918, "title": "Continuum mechanics" }
− v ⋅ n ) dA + ∫ ∂ Ω q ¯ dA + ∫ Ω ρ r dV . {\displaystyle {\cfrac {d}{dt}}\left(\int _{\Omega }\rho ~\eta ~{\text{dV}}\right)\geq \int _{\partial \Omega }\rho ~\eta ~(u_{n}-\mathbf {v} \cdot \mathbf {n} )~{\text{dA}}+\int _{\partial \Omega }{\bar {q}}~{\text{dA}}+\int _{\Omega }\rho ~r~{\text{dV}}.} The scalar entropy ...	{ "page_id": 5918, "title": "Continuum mechanics" }
the Clausius–Duhem inequality may be written as ρ ( e ˙ − T η ˙ ) − σ : ∇ v ≤ − q ⋅ ∇ T T . {\displaystyle {\rho ~({\dot {e}}-T~{\dot {\eta }})-{\boldsymbol {\sigma }}:{\boldsymbol {\nabla }}\mathbf {v} \leq -{\cfrac {\mathbf {q} \cdot {\boldsymbol {\nabla }}T}{T}}.}} == Validity == The validity of the continuum assump...	{ "page_id": 5918, "title": "Continuum mechanics" }
K.; Solem, J. C. (1999). "Nonlinear behavior of some hydrostatically stressed isotropic elastomeric foams". Acta Mechanica. 138 (3–4): 155–162. doi:10.1007/BF01291841. S2CID 120320672. Fung, Y. C. (1977). A First Course in Continuum Mechanics (2nd ed.). Prentice-Hall, Inc. ISBN 978-0-13-318311-5. Irgens, Fridtjov (10 J...	{ "page_id": 5918, "title": "Continuum mechanics" }
Physical Modeling. Germany: Springer. ISBN 978-3-540-20619-4. Gurtin, M. E. (1981). An Introduction to Continuum Mechanics. New York: Academic Press. Lai, W. Michael; David Rubin; Erhard Krempl (1996). Introduction to Continuum Mechanics (3rd ed.). Elsevier, Inc. ISBN 978-0-7506-2894-5. Archived from the original on 6 ...	{ "page_id": 5918, "title": "Continuum mechanics" }
Multiscale modeling or multiscale mathematics is the field of solving problems that have important features at multiple scales of time and/or space. Important problems include multiscale modeling of fluids, solids, polymers, proteins, nucleic acids as well as various physical and chemical phenomena (like adsorption, ch...	{ "page_id": 4003614, "title": "Multiscale modeling" }
method using both classical and quantum mechanical theory which were used to model large complex chemical systems and reactions. == Areas of research == In physics and chemistry, multiscale modeling is aimed at the calculation of material properties or system behavior on one level using information or models from diffe...	{ "page_id": 4003614, "title": "Multiscale modeling" }
On the other hand, a computationally feasible Global climate model (GCM), with grid size ~ 100 km, cannot see the smaller cloud systems. So we need to come to a balance point so that the model becomes computationally feasible and at the same time we do not lose much information, with the help of making some rational gu...	{ "page_id": 4003614, "title": "Multiscale modeling" }
MMM@HPC project Modeling Materials: Continuum, Atomistic and Multiscale Techniques (E. B. Tadmor and R. E. Miller, Cambridge University Press, 2011) An Introduction to Computational Multiphysics II: Theoretical Background Part I Harvard University video series SIAM Journal of Multiscale Modeling and Simulation Internat...	{ "page_id": 4003614, "title": "Multiscale modeling" }
Girls Gotta Eat is a podcast started in 2018 and hosted by Rayna Greenberg and Ashley Hesseltine. Much of the podcast is centered around handing out dating advice to the show's listeners. The podcast is known for its live shows across the United States and its "Is This Weird?" segment. Girls Gotta Eat has gotten in exc...	{ "page_id": 79435556, "title": "Girls Gotta Eat" }
The Type IX secretion system is a specialized protein secretion system found in the Fibrobacteres-Chlorobi-Bacteroidetes superphylum. It plays a crucial role in various cellular processes, including gliding motility and the secretion of virulence factors in Porphyromonas gingivalis. To date, at least nineteen component...	{ "page_id": 79107877, "title": "Type IX secretion system" }
cell. A later discovery that PorT was also necessary for the membrane facilitation of chitinase in F. johnsoniae led to the subsequent observation that the aforementioned list of proteins made up an entirely unique secretion system. Formerly known as Porphyromonas secretion systems (PorSS), due to its discovery on Porp...	{ "page_id": 79107877, "title": "Type IX secretion system" }
There are many genes in the P. gingivalis genome that code for specific parts of the secretion system that are found in various areas, while the genes PorK-PorL-PorM-PorN-PorP are transcribed together. === There are three sub-complexes found within the secretion system: === PorLM and GldLM rotary motor PorKN and GldKN ...	{ "page_id": 79107877, "title": "Type IX secretion system" }
as hydrolytic enzymes, cellulases, chitinases, and proteases, each of which vary in utility for the cell. Secreted virulence factors are used as a coating for the cell and the cargo vesicles that it releases. This coating allows these packaged vesicles to enter into a host cell and impair immune response in the host. V...	{ "page_id": 79107877, "title": "Type IX secretion system" }
are virulence factors that cause around 85% of protein degradation or proteolysis, greatly contributing to inflammatory conditions and the destruction of periodontal tissue. The T9SS also can be a major component to motility for various bacterial systems. The proteins that make up this externally assembled rotary syste...	{ "page_id": 79107877, "title": "Type IX secretion system" }
The molecular formula C9H13N3O5 (molar mass: 243.22 g/mol, exact mass: 243.0855 u) may refer to: Cytarabine, or cytosine arabinoside (ara-C) Cytidine	{ "page_id": 24319780, "title": "C9H13N3O5" }
Gravitational scattering is the alteration of trajectories when two or more celestial objects exchange energy and momentum through close gravitational encounters. This process underpins many dynamical phenomena in astrophysics, from the formation of binary star systems to the ejection of bodies from planetary systems. ...	{ "page_id": 71964454, "title": "Gravitational scattering" }
may have been pushed outward after close encounters with Jupiter or Saturn. After the protoplanetary gas dissipates, multi-planet systems can experience comparable instabilities: orbits shift, and some planets are eventually ejected or spiral into the host star. Planets scattered gravitationally can end on highly eccen...	{ "page_id": 71964454, "title": "Gravitational scattering" }
In condensed-matter physics, a collision cascade (also known as a displacement cascade or a displacement spike) is a set of nearby adjacent energetic (much higher than ordinary thermal energies) collisions of atoms induced by an energetic particle in a solid or liquid. If the maximum atom or ion energies in a collision...	{ "page_id": 20125479, "title": "Collision cascade" }
stopping powers used are averaging fits to experiments, and are thus not perfectly accurate either. The electronic stopping power can be readily included in binary collision approximation or molecular dynamics (MD) simulations. In MD simulations they can be included either as a frictional force or in a more advanced ma...	{ "page_id": 20125479, "title": "Collision cascade" }
becomes a region of vacancies. If the kinetic energy of the atoms in the region of dense collisions is recalculated into temperature (using the basic equation E = 3/2·N·kBT), one finds that the kinetic energy in units of temperature is initially of the order of 10,000 K. Because of this, the region can be considered to...	{ "page_id": 20125479, "title": "Collision cascade" }
higher energies, the Cu ions would most likely lead initially to a linear cascade, but the recoils could lead to heat spikes, as would the initial ion once it has slowed down enough. The concept subcascade breakdown threshold energy signifies the energy above which a recoil in a material is likely to produce several is...	{ "page_id": 20125479, "title": "Collision cascade" }
not be treated equally to the fairly well known process of transfer of heat from hot electrons to an intact crystal structure. Finally, the relaxation phase of the cascade, when the defects formed possibly recombine and migrate, can last from a few ps to infinite times, depending on the material, its defect migration a...	{ "page_id": 20125479, "title": "Collision cascade" }
vicinity of a surface often lead to sputtering, both in the linear spike and heat spike regimes. Heat spikes near surfaces also frequently lead to crater formation. This cratering is caused by liquid flow of atoms, but if the projectile size above roughly 100,000 atoms, the crater production mechanism switches to the s...	{ "page_id": 20125479, "title": "Collision cascade" }
The molecular formula C12H12 may refer to one of many molecules, including: Dodecaheptaene, a straight-chain polyene Cyclododecahexaene ([12]annulene) Cyclododecatriyne [6]Radialene(hexaradialene) Ten dimethylnaphthalene isomers, including: 1,4-Dimethylnaphthalene 2,6-Dimethylnaphthalene Two ethylnapthalene isomers 16 ...	{ "page_id": 24385324, "title": "C12H12" }
AlgaeBase is a global species database of information on all groups of algae, both marine and freshwater, as well as sea-grass. == History == AlgaeBase began in March 1996, founded by Michael Guiry. By 2005, the database contained about 65,000 names. In 2013, AlgaeBase and the Flanders Marine Institute (VLIZ) signed an...	{ "page_id": 7018285, "title": "AlgaeBase" }
of the data was funded by the Irish Government Department of Education and Science's Programme for Research in Third-level Institutions (PRTLI) 2, 3 and 4 programmes, to the Ryan Institute and the Environmental Change Institute, as well as by Atlantic Philanthropies, and the European Union. The synchronisation between ...	{ "page_id": 7018285, "title": "AlgaeBase" }
A barn (symbol: b) is a metric unit of area equal to 10−28 m2 (100 fm2). This is equivalent to a square that is 10−14 m (10 fm) each side, or a circle of diameter approximately 1.128×10−14 m (11.28 fm). Originally used in nuclear physics for expressing the cross sectional area of nuclei and nuclear reactions, today it ...	{ "page_id": 71469, "title": "Barn (unit)" }
with the commonly-used Greek letter beta. They then considered naming it after John Manley, another scientist associated with their work, but considered "Manley" too long and "John" too closely associated with toilets. But this latter association, combined with the "rural background" of one of the scientists, suggested...	{ "page_id": 71469, "title": "Barn (unit)" }
collide over a period of time. The total number of collisions will be directly proportional to the luminosity of the collisions measured over this time. Therefore, the collision count can be calculated by multiplying the integrated luminosity by the sum of the cross-section for those collision processes. This count is ...	{ "page_id": 71469, "title": "Barn (unit)" }
barn Orders of magnitude (area) List of unusual units of measurement List of humorous units of measurement == References == == External links == IUPAC citation for this usage of "barn"	{ "page_id": 71469, "title": "Barn (unit)" }
Chemical thermodynamics is the study of the interrelation of heat and work with chemical reactions or with physical changes of state within the confines of the laws of thermodynamics. Chemical thermodynamics involves not only laboratory measurements of various thermodynamic properties, but also the application of mathe...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
Lewis and Merle Randall. This book was responsible for supplanting the chemical affinity with the term free energy in the English-speaking world. The second was the 1933 book Modern Thermodynamics by the methods of Willard Gibbs written by E. A. Guggenheim. In this manner, Lewis, Randall, and Guggenheim are considered ...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
change in internal energy of a chemical system. It can be calculated from Δ f U r e a c t a n t s o {\displaystyle \Delta _{\rm {f}}U_{\mathrm {reactants} }^{\rm {o}}} , the internal energy of formation of the reactant molecules related to the bond energies of the molecules under consideration, and Δ f U p r o d u c t ...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
coupled to constraining devices, such as pistons or electrodes, to deliver and receive external work. Even for homogeneous "bulk" systems, the free-energy functions depend on the composition, as do all the extensive thermodynamic potentials, including the internal energy. If the quantities { Ni }, the number of chemica...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
a process involved in changing the composition; e.g., a chemical reaction (or many), or movement of molecules from one phase (liquid) to another (gas or solid). We should find a notation which does not seem to imply that the amounts of the components ( Ni ) can be changed independently. All real processes obey conserva...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
minus sign ensures that in a spontaneous change, when the change in the Gibbs free energy of the process is negative, the chemical species have a positive affinity for each other. The differential of G takes on a simple form that displays its dependence on composition change ( d G ) T , P = − A d ξ . {\displaystyle (\m...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
(See Constraints below.) We now relax the requirement of a homogeneous "bulk" system by letting the chemical potentials and the affinity apply to any locality in which a chemical reaction (or any other process) is occurring. By accounting for the entropy production due to irreversible processes, the equality for dG is ...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
The assertion that all spontaneous reactions have a negative ΔG is merely a restatement of the second law of thermodynamics, giving it the physical dimensions of energy and somewhat obscuring its significance in terms of entropy. When no useful work is being done, it would be less misleading to use the Legendre transfo...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
to mention but a few examples. === System constraints === In this regard, it is crucial to understand the role of walls and other constraints, and the distinction between independent processes and coupling. Contrary to the clear implications of many reference sources, the previous analysis is not restricted to homogene...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
ATP to ADP and phosphate can drive the force-times-distance work delivered by living muscles, and synthesis of ATP is in turn driven by a redox chain in mitochondria and chloroplasts, which involves the transport of ions across the membranes of these cellular organelles. The coupling of processes here, and in the previ...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
5. 8: 197–205. Th. De Donder (1922). "Sur le theoreme de Nernst". Bulletin de la Classe des Sciences, Académie Royale de Belgique. Series 5. 8: 205–210. == External links == Chemical Thermodynamics - University of North Carolina Chemical energetics (Introduction to thermodynamics and the First Law) Thermodynamics of ch...	{ "page_id": 5936, "title": "Chemical thermodynamics" }
Melba Newell Phillips (February 1, 1907 – November 8, 2004) was an American physicist and a pioneer science educator. One of the first doctoral students of J. Robert Oppenheimer at the University of California, Berkeley, Phillips completed her PhD in 1933, a time when few women could pursue careers in science. In 1935,...	{ "page_id": 1185584, "title": "Melba Phillips" }
four children. Phillips graduated from Union High School in 1922 at the age of fifteen. Intending to become an educator, Phillips studied mathematics at Oakland City College in Indiana, where she earned a bachelor of arts degree in 1926. Afterwards, Phillips taught at her former high school for two years before enterin...	{ "page_id": 1185584, "title": "Melba Phillips" }
World War II, when she taught at the University of Minnesota (1941–44), Phillips spent a decade as a professor of physics at Brooklyn College (1938–52). She also conducted research on a part-time basis at the Columbia University Radiation Laboratory. In 1945, while teaching at Brooklyn College, Phillips helped organize...	{ "page_id": 1185584, "title": "Melba Phillips" }
to teach elsewhere. Philips was active in the American Association of Physics Teachers throughout her career. She became a member of the AAPT in 1943 and served as its first woman president (1966–67). She also co-edited the organization's official history. In addition, Phillips served on the Commission in College Physi...	{ "page_id": 1185584, "title": "Melba Phillips" }

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