Neutronactivation is the process in which neutron radiation induces radioactivity in materials, and occurs when atomic nucleus atomic nuclei capture free neutron s, becoming heavier and entering excited state s. The excited nucleus often decays immediately by emitting particles such as neutrons, proton s, or alpha particle s. The neutron capture , even after any intermediate decay, often results in the formation of an unstable activation product . Such radioactive nuclei can exhibit half life half lives ranging from small fractions of a second to many years. An example of this kind of a nuclear reaction occurs in the production of cobalt 60 within a nuclear reactor nuclide cobalt 59 n nuclide ... neutron flux es, such as within the cores of nuclear reactors, neutronactivation contributes to material ... materials are more subject to neutronactivation than others, so a suitably chosen low activation ... in a sheet of aluminum foil . The lasting radiation from a nuclear weapon is in part due to the neutronactivation of the bomb itself and the surrounding material, in addition to fission product s. Neutronactivation also has a practical use. Neutronactivation analysis is one of the most sensitive ... of art. Although the activation induces radioactivity in the object, its level is typically low and its lifetime may be short, so that its effects soon disappear. In this sense, neutronactivation is a non ... for radiotherapy . In other cases, and depending on the kinetic energy of the neutron, the capture of a neutron can cause nuclear fission the splitting of the atomic nucleus into two smaller nuclei. If the fission requires an input of energy, that comes from the kinetic energy of the neutron ... Nuclide beryllium 9 n 2 Nuclide helium 4 2n energy In other words, the capture of the neutron by beryllium ... reports series 156.pdf Handbook on Nuclear Activation Cross Sections, IAEA, 1974 http www.nacdl.org ..., November 19, 2007 Category Radiation Category Neutron Radiation Category Radiation effects nuclear ... more details
Science with neutrons In chemistry, neutronactivation analysis NAA is a nuclear reaction nuclear process ... of a sample, and focuses solely on its nucleus. The method is based on neutronactivation and therefore requires a source of neutron s. The sample is bombarded with neutrons, causing the elements to form ... decay rates activity of a radioactive sample. Overview Neutronactivation analysis is a sensitive ... have a KE 0.5 MeV. Activation with fast neutrons is termed Fast NAA FNAA . Another major experimental parameter is whether nuclear decay products gamma rays or particles are measured during neutron irradiation Prompt gamma neutronactivation analysis prompt gamma , or at some time after irradiation ... on irradiated samples it is termed Instrumental NeutronActivation Analysis INAA . In some cases ... the radioisotope of interest, this technique is known as Radiochemical NeutronActivation Analysis ... references DEFAULTSORT NeutronActivation Analysis Category Analytical chemistry Category Scientific ... and irradiated in a suitable reactor at a constant, known neutron flux . A typical reactor used for activation uses uranium Nuclear fission fission , providing a high neutron flux and the highest available sensitivities for most elements. The neutron flux from such a reactor is in the order ... are termed thermal neutrons. Upon irradiation a thermal neutron interacts with the target nucleus via a non elastic collision, causing neutron capture. This collision forms a compound nucleus which ... energy of the thermal neutron with the target nucleus. This excited state is unfavourable and the compound ... is of activation by slow neutrons, slow neutrons are fully moderated within the reactor and have KE 0.5 eV. Medium KE neutrons may also be used for activation, these neutrons have been only partially moderated and have KE of 0.5 eV to 0.5 MeV, and are termed epithermal neutrons. Activation with epithermal neutrons is known as Epithermal NAA ENAA . High KE neutrons are sometimes used for activation ... more details
Science with neutrons Prompt gamma neutronactivation analysis PGNAA is a very widely applicable technique for determining the presence and amount of many elements simultaneously in samples ranging in size from micrograms to many grams. It is a non destructive method, and the chemical form and shape of the sample are relatively unimportant. Typical measurements take from a few minutes to several hours per sample. The technique can be described as follows. The sample is continuously irradiated with a beam of neutron s. The constituent elements of the sample absorb some of these neutrons and emit prompt gamma ray emission prompt gamma ray s which are measured with a gamma ray spectrometer . The energies of these gamma rays identify the neutron capturing elements, while the intensities of the peaks at these energies reveal their concentrations. The amount of analyte element is given by the ratio of count rate of the characteristic peak in the sample to the rate in a known mass of the appropriate elemental standard irradiated under the same conditions. Typically, the sample will not acquire significant long lived radioactivity, and the sample may be removed from the facility and used for other purposes. One of the typical application of PGNAA is an online belt elemental analyzer or bulk material analyzer used in cement , Coal analyzer coal and mineral industries. ref Harder, J. 2009, Material analysis for process control in cement plants , ZKG INTERNAIONAL, 6 7 2009, Volume 62, p. 64 ref References Reflist External links http www.ncnr.nist.gov instruments pgaa http ois.nist.gov nistpubs technipubs recent search.cfm?dbibid 204 DEFAULTSORT Prompt Gamma NeutronActivation Analysis Category Analytical chemistry physics stub chemistry stub ... more details
, adhesion molecules , bacterial products and viral products. Physics Similarly, neutronactivation ... and energy of the emitted particles. Prompt gamma neutronactivation analysis Prompt Gamma NeutronActivation Analysis PGNAA is a rapid, nondestructive, instrumental, nuclear technique which is used for trace and major component analysis of various elements. Electrophysiology Activation refers ...about a requirement for a chemical reaction a step in a software installation process Product activation the calling of a subroutine Subroutine Activation in bio chemical science s generally refers to the Process science process whereby something is prepared or excited for a subsequent reaction . Chemistry In chemistry , activation of molecule s is where the molecules enter a state that avails for a chemical reaction to occur. The phrase activation energy energy of activation ref http chemed.chem.purdue.edu genchem topicreview bp ch22 activate.html The Activation Energy of Chemical Reactions Bot generated title ref refers to the Energy chemistry energy the reactant s must acquire before they can successfully react with each other to produce the Product chemistry products , that is, to reach the transition state . The energy needed for activation can be quite small and the molecules may have ... kinetics . Biology Biochemistry In biochemistry , activation, specifically called bioactivation ... active. Immunology Main Immunologic activation In immunology , activation is the transition of leucocytes ... in the reverse direction. This balance is tightly regulated, since a too small degree of activation causes susceptibility to infections, while, on the other hand, a too large degree of activation causes autoimmune diseases . Activation and deactivation results from a variety of factors, including ... in a high neutron flux and in the nuclear reaction involved, a neutron is Neutron capture captured ... references SIA Category Chemical kinetics da Aktivering de Aktivierung fr Activation nl Activering ... more details
, neutron capture often results in neutronactivation , inducing radioactivity . In particular, knowledge .... This forms the basis of neutronactivation analysis NAA and prompt gamma neutronactivation analysis ... the process of neutronactivation , which is a type of neutron capture . Experimental fusion power nuclear ...About the subatomic particle other uses Neutron disambiguation pp move indef Infobox Particle bgcolour classification Baryon name Neutron image Image Quark structure neutron.svg 250px caption The quark structure of the neutron. The color assignment of individual quarks is not important, only that all ... Neutron , SubatomicParticle Neutron0 , SubatomicParticle Nucleon0 mass val 1.674927351 74 ... mean lifetime val 881.5 15 u s Free neutron free electric charge val 0 u elementary charge e br val ... sup magnetic moment Neutron magnetic moment val 0.96623647 23 e 26 Joule J Tesla unit T sup 1 ... angular momentum J sup Intrinsic parity P sup frac 1 2 frac 1 2 sup sup The neutron is a subatomic particle subatomic hadron particle which has the symbol SubatomicParticle Neutron or SubatomicParticle ... repulsion being stronger than the attraction of the strong force. The number of neutrons is the neutron ... are produced in nuclear fission and nuclear fusion fusion . Dedicated neutron source s like research reactor s and spallation spallation sources produce free neutrons for use in irradiation and in neutron scattering experiments. Even though it is not a chemical element , the free neutron is sometimes ..., and is sometimes referred to as neutronium . Citation needed date April 2010 The neutron has been the key to nuclear power production. After the neutron was discovered in 1932, it was realized in 1933 ..., Ernest Rutherford conceptualized the possible existence of the neutron. ref name chemed.chem.purdue.edu ... the atomic nucleus. He considered the neutron to be a neutral double consisting of an electron ... Chadwick first James year 1932 title Possible Existence of a Neutron journal Nature journal Nature volume ... more details
Activation products are materials made radioactive by neutronactivation . Fission products and actinide s produced by neutron absorption of nuclear fuel itself are normally referred to by those specific names, and activation product reserved for products of neutron capture by other materials, such as structural components of the nuclear reactor or nuclear bomb , the reactor coolant, control rods or other neutron poison s, or materials in the environment. All of these, however, need to be handled as radioactive waste . Some nuclides originate in more than one way, as activation products or fission products. Activation products in a reactor s primary coolant loop are a main reason why reactors use a chain of two or even three coolant loops linked by heat exchanger s. Fusion reactor s will not produce radioactive waste from the fusion product nuclei themselves, which are normally just helium 4 , but generate high neutron fluxes, so activation products are a particular concern. Activation product radionuclides include class wikitable sortable Nuclide See also Halflife br years Parent Tritium 12.3 Lithium 6,7 br Boron 10 br Deuterium Beryllium 10 1,530,000 Boron 10 Carbon 14 5,730 Nitrogen 14 br Carbon 13 Sodium 24 Fast breeder 0.0017 Sodium 23 Sulfur 35 0.24 Chlorine 35 1 branch Chlorine 36 301,000 Chlorine 35 Argon 39 269 Argon 38 Iron 55 2.73 Iron 54 Nickel 59 76,000 Nickel 58 Cobalt 60 5.27 Cobalt 59 Nickel 63 100 Nickel 62 Molybdenum 93 4,000 Molybdenum 92 Niobium 93m 16 Niobium 94 20,300 Niobium 93 Technetium 99 LLFP 211,000 Molybdenum 98 Silver 108m 418 Silver 107 Cadmium 113m 13 Cadmium 112 Tin 121m http www.nrc.gov reading rm doc collections nuregs contract cr6567 cr6567.pdf 56 Tin 120 Lead 205 Q 51KeV 15,300,000 Lead 204 Polonium 210 LBE 0.379 Bismuth 209 External ... Activation Cross Sections, IAEA, 1974 http www.nndc.bnl.gov databases databases.html Nuclear Structure ... Category Neutron Radiation Category Radiation effects Category Nuclear materials nuclear stub ... more details
may be more penetrating than a high energy neutron. Health hazards and protection In health physics neutron radiation is considered a fourth radiation hazard alongside the other types of radiation. Another, sometimes more severe hazard of neutron radiation, is neutronactivation , the ability of neutron ... , widely used in radiocarbon dating . See also NeutronactivationNeutron emission Neutron bomb Neutron ...lead too short date June 2010 Neutron radiation is a kind of ionizing radiation which consists of free neutron s. A result of nuclear fission or nuclear fusion , it consists of the release of free neutrons ... Neutron source See also Category Neutron sources Neutron s may be emitted from nuclear fusion or nuclear ... or reactions from particle interactions such as from cosmic rays or particle accelerators . Large neutron ... accelerators such as the Spallation Neutron Source . Neutron radiation was discovered as a result ... into a carbon atomic nucleus nucleus and emitting a neutron , Beryllium Be alpha particle , neutron ... , neutron n cross section physics nuclear reaction probability is still a common neutron source. Uses Neutron temperature Cold , thermal and hot neutron radiation is most commonly used for neutron scattering scattering and neutron diffraction diffraction experiments in order to assess the properties ... state chemistry , materials science , geology , mineralogy and related sciences. Neutron radiation is also used in select facilities to Boron Neutron Capture Therapy treat cancerous tumors due to its ... of industrial parts termed neutron radiography when using film, neutron radioscopy when taking a digital image, such as through image plates, and neutron tomography for three dimensional images. Neutron ... reliability explosives industry. Ionization mechanisms and properties Neutron radiation is often ..., neutron interactions are largely ionizing, for example when neutron absorption results in gamma ... from a neutron interaction is ionized and causes more traditional subsequent ionization in other ... more details
unref date July 2011 Infobox Album See Wikipedia WikiProject Albums Name Activation Portal Type studio Artist Alien Project Cover Activation Portal.jpeg Released 2007 Recorded Genre Length Label Producer Last album Space Jam br 2004 This album Activation Portal br 2007 Next album Activation Portal is the latest album by Alien Project . Track listing Super Buster Missing Linker NRG Tweaky rmx Deeper Activation Portal Get Up Groovy rmx Yellow Blaze Aztechno Dream rmx 2000s trance album stub Category 2007 albums Category Alien Project albums ... more details
Spreading activation is a method for searching associative networks, neural network s, or semantic network ... network with weights or activation and then iteratively propagating or spreading that activation out to other nodes linked to the source nodes. Most often these weights are real values that decay as activation ... to as marker passing. Activation may originate from alternate paths, identified by distinct markers, and terminate when two alternate paths reach the same node. Spreading activation models are used in cognitive psychology ref name collins Collins, Allan M. Loftus, Elizabeth F., A spreading activation .... http act r.psy.cmu.edu publications pubinfo.php?id 66 A spreading activation theory of memory. Journal of Verbal Learning and Verbal Behavior , 1983 ref to model the fan out effect. Spreading activation can also be applied in information retrieval , ref name preece S. Preece, A spreading activation .... ref ref name crestani Fabio Crestani. Application of Spreading Activation Techniques in Information ... 1...N each having an associated activation value A i which is a real number in the range 0.0 ... 1.0 ... Boosting item keyword search with spreading activation Aswath, D. Ahmed, S.T. Dapos cunha, J. Davulcu ... setting all activation values A i to zero. Set one or more origin nodes to an initial activation value ... having an activation value A i greater than the node firing threshold F For each Link i , j ... factor. If a target node receives an adjustment to its activation value so that it would exceed 1.0, then set its new activation value to 1.0. Likewise maintain 0.0 as a lower bound on the target node s activation value should it receive an adjustment to below 0.0. Once a node has fired it may not fire .... Nodes receiving a new activation value that exceeds the firing threshold F are marked for firing on the next spreading activation cycle. If activation originates from more than one node, a variation of the algorithm permits marker passing to distinguish the paths by which activation is spread ... more details
Activation key may refer to Product activation Product key Volume license key Key changer software Dab Short pages monitor This long comment was added to the page to prevent it being listed on Special Shortpages. It and the accompanying monitoring template were generated via Template Longcomment. Please do not remove the monitor template without removing the comment as well. ... more details
marketing Marketing activation is the execution of the marketing mix as part the marketing process. The activation ... analytics . Depending on the business objective, two types of marketing activation can be used as part of a marketing strategy. Brand activation, sometimes called brand engagement which focuses on building a longer term emotional connection between the brand and the customer. Activation based on direct response marketing will focus on generating immediate sales transactions. Planning the activation ... customer groups to target. By focusing on some fewer influencers only, activation can become more efficient ... source of information for planning marketing activation. A common practice is to use customer relationship management tools and techniques to augment the impact of marketing activation because CRM provides an integrative framework in which marketing activation and customer activities ... DILIMA accessdate 18 August 2011 ref Challenges A successful marketing activation will allow businesses ... will face in putting in place a marketing activation program. One of the challenges is dealing ... to adapt rapidly. This poses a challenge because, for example, direct marketing activation triggers ... accessdate 18 August 2011 ref Another challenge related to marketing activation has to do with reaching ..., it engages in unique marketing activation, including strong use of PR and events targeted at black ... PRWeek date October 1, 2010 ref Data driven marketing activation Over the years, marketing activation has become more and more data driven. This allows marketers to be more precise in their actions ... important because marketing activation usually entails a universal blast of information to all consumers. Oftentimes, only a small proportion of the consumers react positively to such activation ... in marketing activation. For example, video based measurement ... provides visibility into shopper engagement and behaviour relative to exact marketing activation, enabling a holistic approach to shopper ... more details
is now energetically favorable. In chemistry , activation energy is a term introduced in 1889 by the Swedish ... reaction to occur. Activation energy may also be defined as the minimum energy required to start a chemical reaction. The activation energy of a reaction is usually denoted by E sub a sub , and given in units of joule per mole kilojoules per mole . Activation energy can be thought of as the height ... than the activation energy. At a more advanced level, the Arrhenius Activation energy term from the Arrhenius ... of the reaction rate to temperature. There are two objections to associating this activation ... reaction rates. Negative activation energy In some cases, rates of reaction decrease with increasing ... reactions exhibiting these negative activation energies are typically barrierless reactions, in which ... The Arrhenius equation gives the quantitative basis of the relationship between the activation energy and the rate at which a reaction proceeds. From the Arrhenius equation, the activation energy ... rate constant reaction rate coefficient . While this equation suggests that the activation ... Catalysis Image Activation energy.svg right thumb 360px The relationship between activation energy ... to initiate the reaction. A substance that modifies the transition state to lower the activation ... the catalyst lowers the activation energy, it does not change the energies of the original reactants or products. Rather, the reactant energy and the product energy remain the same and only the activation ... Mean kinetic temperature External links http www.iupac.org goldbook A00102.pdf Activation energy from ... bp ch22 activate.html The Activation Energy of Chemical Reactions Category Chemical kinetics Category ... fr nergie d activation gl Enerx a de activaci n ko id Energi aktivasi it Energia ... more details
In immunology , activation is the transition of leucocytes and other cell types involved in the immune system . On the other hand, deactivation is the transition in the reverse direction. This balance is tightly regulated, since a too small degree of activation causes susceptibility to infection s, while, on the other hand, a too large degree of activation causes autoimmune diseases . Factors Activation and deactivation results from a variety of factors, including cytokines , soluble receptor s, arachidonic acid metabolites, steroids , receptor antagonists , adhesion molecules , bacterial products and viral products. class wikitable Overview of activating and deactivating factors. Activation Deactivation Cytokines IFN GM CSF M CSF Interleukin 6 IL 6 TNF Macrophage migration inhibitory factor MIF CCL2 Interleukin 4 IL 4 Interleukin 10 IL 10 Interleukin 13 IL 13 TGF Soluble receptor s sIL 1R sIL 6R sTNFR sCD14 Arachidonic acid metabolites PGE2 LTB4 Steroids Corticosteroids Receptor antagonists IL 1Ra Adhesion molecules 2 integrins Fc receptors CD14 P selectin CD45 Bacterial products lipopolysaccharide LPS fMetLeuPhe Viral products dsRNA BCRF1 Interleukin 10 IL 10 homologue T2 biochemistry T2 sTNFR homologue M T7 sINF R homologue See also Immune system Category Immunology ... more details
Unreferenced date November 2006 Plasma activation or Plasma functionalization . It is done with the intent to alter or improve adhesion properties of surfaces prior to coating, painting, etc. In most cases, the surface in question is surface of a polymer material and weakly ionised oxygen plasma physics plasma is used. Surface activation is a result of following processes Removal of weak boundary layers. Plasma removes surface layers with the lowest molecular weight , at the same time it oxidation oxidises the uppermost atomic layer of the polymer. Cross linking of surface molecules. Oxygen radicals and UV radiation , if present help break up bonds and promote the three dimensional chemical bond cross bonding of molecules Generation of polar groups. Oxidation of the polymer is responsible for the increase in chemical polarity polar groups which is directly related to the adhesion properties of the polymer surface. See also List of plasma physics articles DEFAULTSORT Plasma Activation Category Plasma processing Chem stub ru ... more details
Refimprove date April 2011 Product activation is a license validation procedure required by some Proprietary software proprietary computer software programs. In one form, product activation refers to a method invented by Ric Richardson and patented US 5,490,216 by Uniloc where a software application Hash function hashes hardware serial numbers and an ID number specific to the product s license a product key to generate a unique CD key installation ID . This installation ID is sent to the manufacturer to verify the authenticity of the product key and to ensure that the product key is not being used for multiple installations. Alternatively, the software vendor sends the user a unique product serial number. When the user installs the application it requests that the user enter their product serial number, and checks it with the vendor s systems over the Internet . The application obtains the license ... required with the vendor s systems. Some activation systems also support activation on user systems ... terminal. Microsoft first used product activation in Microsoft Word Microsoft Word 97 sold ... Microsoft Publisher 98 in the Brazil ian market. Microsoft then rolled out product activation ... the product via the Internet. After its success, the product activation system was extended ... before reactivating it on the new machine. An early example of product activation was in the MS DOS ... key, the software deliberately crashed. The software has long since had the entire activation ... require users to transfer activation when moving a product from one computer to another, when ... date September 2009 See also Microsoft Product Activation CD key Digital rights management Dongle References ... Activation http www.vttoth.com dontactivate.asp table List of products requiring activation http agilis sw.com casestudy NumeriX.html Case study of a software vendor s use of activation DEFAULTSORT Product Activation Category Software licenses ar ca Activaci de producte de Produktaktivierung ... more details
The entropy of activation is one of the two parameters typically obtained from the temperature dependence of a reaction rate, when these data are analysed using the Eyring equation . Symbolized S sup sup , the entropy of activation provides clues about the molecularity of the rate determining step in a reaction, i.e. whether the reactants are bonded to each other, or not. Positive values suggest that entropy increases upon achieving the transition state, which often indicates a Dissociative substitution dissociative mechanism . Negative values for S sup sup indicate that entropy decreases upon achieving the transition state, which often indicates an Associative substitution associative mechanism . Values near zero are difficult to interpret. ref J. H. Espenson Chemical Kinetics and Reaction Mechanism McGraw Hill, 1981, ISBN 0 070019667 2. ref References references Category Chemical kinetics ... more details
. This activation function is linear, and therefore has the same problems as the binary function. In addition ... function sigmoid activation function. One realistic model stays at zero until input current is received ... s is a sigmoidal activation function in the form of a hyperbolic tangent. Two forms of this function ... with certain types of computational problems. Alternative structures A special class of activation ... , which are extremely efficient as universal function approximators. These activation functions .... Support vector machines SVMs can effectively utilize a class of activation functions that includes ... hyperplane based on a few training inputs called support vectors math x math . The activation ... to the activation function, but they take a unique form in the perceptron as math , phi v i tanh ... certain conditions for convergence. These machines can also accept arbitrary order polynomial activation ... year 1998 publisher Prentice Hall location isbn 0 13 273350 1 ref Activation function having types Identity ... more details
Behavioral activation is a third generation behavior therapy for treating major depressive disorder depression ... underpinnings Behavioral activation emerged from a component analysis of cognitive behavioral ... and reduce punishment. The theoretical underpinnings of behavioral activation ref Jacobson, N.S. Martell, C.R. & Dimidjian, S. 2001 . Behavioral Activation for depression Returning to contextual roots ... long term patterns which may lead to dysthymia . Methods The behavioral activation BA approach to depression ..., D.W. year 2004 title A Brief Behavioral Activation Treatment for Depression journal Behavior ... group who did not receive the same treatment. The results of those who received behavioral activation ... since piloted ref Cullen, J.M. Spates, C.R. Pagoto, S. & Doran, N. 2006 . Behavioral Activation ..., C.R. Pagoto, S. & Kalata, A. 2006 . A Qualitative And Quantitative Review of Behavioral Activation ... ref Research support A recent review of behavioral activation studies for depression found ... name spates pagoto kalata 2006 A large scale treatment study found behavioral activation to be more ... author Dimidjian, S. year 2006 title Randomized Trial of Behavioral Activation, Cognitive Therapy ... activation has been applied to anxiety and appears to give promising results. ref Hopko, D.R. Robertson, S.M.C. & Lejuez, C.W. 2006 . Behavioral Activation for Anxiety Disorders. The Behavior ..., M. year 2006 title Effect of Behavioral Activation Treatment on Fibromyalgia Related Pain Anxiety ... therapy believe that behavioral activation will have much to offer other areas such as post traumatic ... generation behavior therapies Behavioral activation comes under the heading clinical behavior analysis ... psychotherapy FAP . Behavioral activation owes its basis to Charles Ferster s Functional Analysis ... in behavior therapy which covers behavioral activation. ref http worldcenterba.com index.html World Association for Behavior Analysis ref References reflist 2 DEFAULTSORT Behavioral Activation Category ... more details
Sorry not sure where to put talk P added refs and rewritten. dopant activation isnt always done with rapid thermal processing so think needs it own stub Dopant Activation is the process of obtaining the desired electronic contribution from dopant impurity species in a semiconductor host. ref cite book title Dopant dopant and dopant defect processes underlying activation kinetics last Mokhberi first Ali authorlink coauthors year 2003 publisher Stanford Unniversity location isbn page pages 186 url accessdate ref The term is often restricted to the application of thermal energy following the ion implantation of dopants. In the most common industrial example, rapid thermal processing is applied to silicon following the ion implantation of dopants such as phosphorus, arsenic and boron. ref cite journal last1 Pelaz first1 last2 Venezia first2 year 1999 title Activation and deactivation of implanted B in Si journal Applied Physics Letters volume 75 issue pages 662 publisher doi url http apl.aip.org resource 1 applab v75 i5 p662 s1 accessdate ref Vacancies generated at elevated temperature 1200 C facilitate the movement of these species from crystallographic defect interstitial to crystallographic defect substitutional lattice sites while amorphous solid amorphization damage from the implantation process recrystallization recrystallizes . A relatively rapid process, peak temperature is often maintained for less than one second to minimize unwanted chemical diffusion . ref http www.thinfilmmfg.com subscribers article06 junctions10Mar06.htm faster New activation anneals help dopants stay put ref References references Category Semiconductor material structures Electronics stub ... more details
Endothelial activation is a proinflammatory and Coagulation procoagulant state of the endothelial cell s lining the Lumen anatomy lumen of blood vessel s. It is most characterized by an increase in interactions with white blood cell s leukocytes , and it is associated with the early states of atherosclerosis and sepsis , among others. ref name Alom cite journal author Alom Ruiz SP, Anilkumar N, Shah AM title Reactive oxygen species and endothelial activation journal Antioxid Redox Signal year 2008 volume 10 issue 6 pages 1089 100 pmid 18315494 doi 10.1089 ars.2007.2007 ref It is also implicated in the formation of deep vein thrombosis . ref name Whatis cite journal author Bovill EG, van der Vliet A title Venous valvular stasis associated hypoxia and thrombosis what is the link? journal Annu Rev Physiol year 2011 volume 73 issue pages 527 45 pmid 21034220 doi 10.1146 annurev physiol 012110 142305 ref As a result of activation, enthothelium releases Weibel Palade body Weibel Palade bodies . ref name Lopez cite journal author L pez JA, Chen J title Pathophysiology of venous thrombosis journal Thromb Res year 2009 volume 123 issue Suppl 4 pages S30 4 pmid 19303501 doi 10.1016 S0049 3848 09 70140 9 ref See also Endothelial dysfunction References reflist circulatory stub Category Circulatory system ... more details
wiktionary neutronNeutron is a subatomic particle. Neutron may also refer to Neutron bomb Neutron bot , an XMPP bot written in Python programming language Python using xmpppy library Neutron degenerate matter Neutron game , an abstract strategy game Neutron matter Neutron star In fiction Neutron comics , the name given to three comic book characters Neutron DC Comics , a DC Comics character Neutron Linus , an Italian comics character that appeared in Linus Neutron Marvel Comics , a Marvel Comics character Neutron Solstice , the third book in the Deathlands series Neutron Star short story Neutron Star short story , a short story by Larry Niven See also Jimmy Neutron disambiguation disambig pl Neutron ujednoznacznienie fi Roni Neutroni t smennyssivu ... more details
Activation syndrome is a form of sometimes suicidal or homicidal stimulation or agitation that can occur in response to some psychoactive drug s. ref http www.breggin.com recentregulatory.pbreggin.2006.pdf ref A study of paroxetine found that 21 out of 93 23 percent of youth taking Paxil reported manic like symptoms which included hostility, emotional lability and nervousness. ref citation url http www.lib.umd.edu drum handle 1903 6668 title Adolescents and Antidepressants Analyzing a Social Scientific Controversy author AD Nelson year 2007 ref Pfizer has denied that sertraline can cause such effects. ref http www.healyprozac.com AcademicStalking Post 203 20 20Pfizer 20letter 20re 20Healy.pdf ref ref http www.ahrp.org ethical HealyResponseToPfizer.pdf ref Approximately 25 to 40 perecent of patients who take tricyclic antidepressant s experience activation syndrome upon initial titration. ref http www.aafp.org afp 980515ap saeed.html ref References reflist Category Psychoactive drugs disease stub ja ... more details
mechanism that helps keep nuclear reactors under control. Uses Neutronactivation analysis can be used ...Refimprove date April 2010 sprotect small yes File Chart of Nuclides Thermal neutron capture cross sections.png thumb right 370px Chart of nuclides showing thermal neutron capture cross section values Science with neutrons Neutron capture is a kind of nuclear reaction in which an atomic nucleus collides with one or more neutron s and they merge to form a heavier nucleus. ref name University of Ottawa ... electrostatically . ref name University of Ottawa Department of Physics Neutron capture plays ... by nuclear fusion , but can be formed by neutron capture. ref name University of Ottawa Department of Physics Neutron capture at small neutron flux File Au198.PNG thumb left Decay scheme of sup 198 sup Au At small neutron flux , as in a nuclear reactor , a single neutron is captured by a nucleus ..., the atomic number rises by one. Neutron capture at high neutron flux The r process happens inside stars if the neutron flux density is so high that the atomic nucleus has no time to decay via beta emission in between neutron captures. The mass number therefore rises by a large amount while ... The absorption neutron cross section of an isotope of a chemical element is the effective cross ... of neutron capture. It is usually measured in barn unit barns b . Absorption cross section is often highly dependent on neutron energy . Two of the most commonly specified measures are the cross section for thermal neutron absorption, and resonance integral which considers the contribution of absorption peaks at certain neutron energies specific to a particular nuclide , usually above the thermal range, but encountered as neutron moderation slows the neutron down from an original high energy ... related to mineral exploration and security. Neutron absorbers main Neutron poison expert subject Physics section date October 2011 refimprove section date December 2011 The most prolific neutron absorbers ... more details
. Similar speed distributions are obtained for neutron radiation neutrons upon Neutron moderator moderation . The neutron detection temperature , also called the neutron energy , indicates a free neutron free neutron s kinetic energy , usually given in electron volt s. The term temperature is used, since hot, thermal and cold neutrons are Neutron moderator moderated in a medium with a certain temperature. The neutron energy distribution is then adopted to the Maxwell Boltzmann distribution Maxwellian ... the kinetic energy is of the free neutron. Kinetic energy, speed and wavelength of the neutron are related through the Matter wave De Broglie relation . Neutron energy distribution ranges Moderated and other, non thermal neutron energy distributions or ranges are listed below Fast neutrons have kinetic ... rough guidelines, as the energy ranges are actually very vague descriptions of a neutron s energy, with no strict cut off points. Fast neutrons A fast neutron is a free neutron with a kinetic energy ... km second s , or higher. They are named fast neutron s to distinguish them from lower energy thermal ... neutrons via a process called moderation. This is done with a neutron moderator . In reactors, typically .... Thermal neutrons A thermal neutron is a free neutron with a kinetic energy of about 0.025 electron ... with nuclei scattering in a medium neutron moderator at this temperature, neutron s arrive ... and often much larger effective neutron absorption Neutron cross section cross section for a given ... a heavier, often unstable isotope unstable isotope of the chemical element as a result neutronactivation . Fast reactor and thermal reactor compared Most nuclear reactor fission reactor s are thermal reactor s that use a neutron moderator to slow down thermalize the neutrons produced by nuclear ... moderated reactor s can even use natural uranium as these moderators have much lower neutron capture Neutron cross section cross section s than light water. ref http www.world nuclear.org education ... more details
Oocyte or ovum egg activation is a series of processes that occur in the oocyte after fertilisation . Sperm entry causes calcium release into the oocyte. In mammals, this has been proposed to be caused by the introduction of phospholipase C isoform zeta PLC from the sperm cytoplasm, although this remains to be established definitively. Activation of the ovum includes the following events Cortical reaction to block against other sperm cells Activation of egg metabolism Reactivation of meiosis DNA synthesis Sperm trigger of egg activation The sperm may trigger egg activation via the interaction between a sperm protein and an egg surface receptor. It is possible that a receptor is activated by the sperm binding which activates a tyrosine kinase which then activates phospholipase C PLC . The inositol signaling system has been implicated as the pathway involved with egg activation. IP sub 3 sub and DAG are produced from the cleavage of PIP sub 2 sub by phospholipase C. However, another hypothesis is that a soluble sperm factor diffuses from the sperm into the egg cytosol upon sperm oocyte fusion. The results of this interaction could activate a signal transduction pathway that uses second messengers . A novel PLC isoform, PLC , may be the equivalent of the mammalian sperm factor. A recent paper shows that mammaliam sperm contain PLC zeta which can start the signaling cascade. ref cite journal author Saunders C, Larman M, Parrington J, Cox L, Royse J, Blayney L, Swann K, Lai F title PLC zeta a sperm specific trigger of Ca 2 oscillations in eggs and embryo development. journal Development volume 129 issue 15 pages 3533 44 year 2002 pmid 12117804 ref Fast and slow block to polyspermy See Cortical reaction Polyspermy is the condition when multiple sperm fuse with a single egg. This results in duplications of genetic material. In sea urchins, the block to polyspermy comes from ... oocyte activation Oocyte activation may be artificially facilitated by calcium ionophore s, something ... more details
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