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Radioactive biography, Radioactive discography
For other uses, see Radioactive (disambiguation).Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting radiation in the form of particles or electromagnetic waves.This decay, or loss of energy, results in an atom of one type, called the parent nuclide transforming to an atom of a different type, called the daughter nuclide.This is a random process on the atomic level, in that it is impossible to predict when a particular atom will decay, but given a large number of similar atoms, the decay rate, on average, is predictable.The SI unit of radioactive decay (the phenomenon of natural and artificial radioactivity) is the becquerel (Bq).One Bq is defined as one transformation (or decay) per second.At present it is equal (by definition) to the activity of any radionuclide decaying with a disintegration rate of 3.The trefoil symbol is used to indicate radioactive material.Explanation
2 Discovery
3 Modes of decay
4 Decay chains and multiple modes
5 Occurrence and applications
6 Radioactive decay rates
6.The strong nuclear force, not observed at the familiar macroscopic scale, is the most powerful force over subatomic distances.The electrostatic force is also significant, while the weak nuclear force is responsible for beta decay.Such a collapse (a decay event) requires a specific activation energy.In the case of a snow avalanche, this energy classically comes as a disturbance from outside the system, although such disturbances can be arbitrarily small.In the case of an excited atomic nucleus, the arbitrarily small disturbance comes from quantum vacuum fluctuations.The resulting transformation alters the structure of the nucleus.Such a reaction is thus a nuclear reaction, in contrast to chemical reactions, which also are driven by entropy, but which involve changes in the arrangement of the outer electrons of atoms, rather than their nuclei.However, these are not considered decay.Rather, they are examples of induced nuclear reactions.Discovery
Radioactivity was first discovered in 1896 by the French scientist Henri Becquerel, while working on phosphorescent materials.All results were negative until he used uranium salts.The result with these compounds was a deep blackening of the plate.Clearly there was a form of radiation that could pass through paper that was causing the plate to blacken.Different types of decay can occur, but Rutherford was the first to realize that they all occur with the same mathematical approximately exponential formula (see below).For lack of better terms, the rays were given the alphabetic names alpha, beta and gamma, still in use today.It was obvious from the direction of electromagnetic forces that alpha rays carried a positive charge, beta rays carried a negative charge, and gamma rays were neutral.From the magnitude of deflection, it was clear that alpha particles were much more massive than beta particles.Passing alpha particles through a very thin glass window and trapping them in a discharge tube allowed researchers to study the emission spectrum of the resulting gas, and ultimately prove that alpha particles are helium nuclei.Shortly after discovery of the neutron in 1932, it was discovered by Enrico Fermi that certain rare decay reactions yield neutrons as a decay particle.Isolated proton emission was eventually observed in some elements.The early researchers also discovered that many other chemical elements besides uranium have radioactive isotopes.The two elements' chemical similarity would otherwise have made them difficult to distinguish.The dangers of radioactivity and of radiation were not immediately recognized.In 1927 Hermann Joseph Muller published research showing genetic effects, and in 1946 was awarded the Nobel prize for his findings.Before the biological effects of radiation were known, many physicians and corporations had begun marketing radioactive substances as patent medicine and radioactive quackery.Marie Curie spoke out against this sort of treatment, warning that the effects of radiation on the human body were not well understood (Curie later died from aplastic anemia assumed due to her work with radium, but later examination of her bones showed that she had been a careful laboratory worker and had a low burden of radium.The column "Daughter nucleus" indicates the difference between the new nucleus and the original nucleus.This energy is released as kinetic energy of the emitted particles.The energy remains associated with a measure of mass of the decay system invariant mass, inasmuch the kinetic energy of emitted particles contributes also to the total invariant mass of systems.Decay chains and multiple modes
The daughter nuclide of a decay event may also be unstable (radioactive).In this case, it will also decay, producing radiation.The resulting second daughter nuclide may also be radioactive.This can lead to a sequence of several decay events.This is called a decay chain.Some radionuclides may have several different paths of decay.These lightest stable nuclides (including deuterium) survive to today, but any radioactive isotopes of the light elements produced in the Big Bang (such as tritium) have long since decayed.Thus, all radioactive nuclei are therefore relatively young with respect to the birth of the universe, having formed later in various other types of nucleosynthesis in stars (particularly supernovae), and also during ongoing interactions between stable isotopes and energetic particles.Earth's upper atmosphere due to interactions between cosmic rays and nitrogen.Radioactive decay has been put to use in the technique of radioisotopic labeling, used to track the passage of a chemical substance through a complex system (such as a living organism).The presence of the substance in one or another part of the system is determined by detecting the locations of decay events.Because the process is not thought to vary significantly in mechanism over time, it is also a valuable tool in estimating the absolute ages of certain materials.The "amount of substance" can be the unit of either mass or volume.Low activities are also measured in disintegrations per minute (dpm).However, it is equally likely to decay at any time.This characteristic time is called the time constant of the process.In radioactive decay, this process time constant it also the mean lifetime for decaying atoms.The previous exponential function generally represents the result of exponential decay.It is only an approximate solution, for two reasons.Secondly, because it describes a random process, it is only statistically true.Contains tabulated information on radioactive decay types and energies.All text is available under the terms of the GNU Free Documentation License.This article does not cite any references or sources.December 2007)
Please help improve this article by adding citations to reliable sources.Periodic table colored according to the radioactivity of the most stable isotope .Very little is known about these elements, and will likely never receive any attention outside research laboratories.Radioactive contamination is the uncontrolled distribution of radioactive material in a given environment.The amount of radioactive material released in an accident is called the source term.Sources of contamination
Radioactive contamination is typically the result of a spill or accident during the production or use of radionuclides (radioisotopes), an unstable nucleus which has excessive energy.Contamination may occur from radioactive gases, liquids or particles.Radioactive contamination may also be an inevitable result of certain processes, such as the release of radioactive xenon in nuclear fuel reprocessing.In cases that radioactive material cannot be contained, it may be diluted to safe concentrations.Nuclear fallout is the distribution of radioactive contamination by a nuclear explosion.Containment is what differentiates radioactive material from radioactive contamination.Therefore, radioactive material in sealed and designated containers is not properly referred to as contamination, although the units of measurement might be the same.Measurement
Radioactive contamination may exist on surfaces or in volumes of material or air.In the case of fixed contamination, the radioactive material cannot by definition be spread, but it is still measurable.Hazards
In practice there is no such thing as zero radioactivity.These tiny levels of radiation are not any more harmful than sunlight, but just as excessive quantities of sunlight can be dangerous, so too can excessive levels of radiation.Low level contamination
The hazards to people and the environment from radioactive contamination depend on the nature of the radioactive contaminant, the level of contamination, and the extent of the spread of contamination.Low levels of radioactive contamination pose little risk, but can still be detected by radiation instrumentation.High level contamination
High levels of contamination may pose major risks to people and the environment.People can be exposed to potentially lethal radiation levels, both externally and internally, from the spread of contamination following an accident (or a deliberate initiation) involving large quantities of radioactive material.Biological effects
See also: Radiation poisoning
The biological effects of internally deposited radionuclides depend greatly on the activity and the biodistribution and removal rates of the radionuclide, which in turn depends on its chemical form.Some radionuclides may target specific organs and have much lower removal rates.For instance, the thyroid gland takes up a large percentage of any iodine that enters the body.If large quantities of radioactive iodine are inhaled or ingested, the thyroid may be impaired or destroyed, while other tissues are affected to a lesser extent.Radioactive iodine is a common fission product; it was a major component of the radiation released from the Chernobyl disaster, leading to many cases of pediatric thyroid cancer and hypothyroidism.On the other hand, radioactive iodine is used in the diagnosis and treatment of many diseases of the thyroid precisely because of the thyroid's selective uptake of iodine.Means of contamination
Radioactive contamination can enter the body through ingestion, inhalation, absorption, or injection.For this reason, it is important to use personal protective equipment when working with radioactive materials.Radioactive contamination may also be ingested as the result of eating contaminated plants and animals or drinking contaminated water or milk from exposed animals.This page was last modified on 7 June 2008, at 03:22.All text is available under the terms of the GNU Free Documentation License.RADIOACTIVE ENERGY DRINK SPONSORS MEMORIAL DAY BASH AT HOUDINI'S MANSION IN HOLLYWOOD
Radioactive Energy Drink was the official sponsor at a Memorial Day Bash that took place at Houdini's Mansion in Hollywood.Radioactive kept the party ''glowing!Team Radioactive attends Memorial Day Weekend event at Balance MotoX in Bowling Green, KY.International Market in Ohio on May 24, 2008.Team Radioactive attends 2008 Toyota Bluegrass Championship MX Series, Round 2 at Podium One in Charlestown, IN.Sensa Beverage Company, All rights reserved.Technical Services
Radio and Audio
I.Training at rural telecentres in NepalRadioActive Nepal broadcasts radio recorded at rural telecentres around Kathmandu.Filming for RadioActive NepalJasleen Kaur Sethi has made a short film about the building of RadioActive Nepal.New Community Radio Legislation in India02RadioActive India!Our technical team can help you decide what equipment will suit your needs.NGOs to start and develop community radio stations.Copyright 2008 RadioActive Consulting Ltd.No one could have ever predicted that he would return to the top of the charts three years later, relatively fit and healthy, with a new band that fulfilled all of the promises of his old group.Black Grape is surreal, funky, profane, and perversely joyous overflowing with casual eclecticism and giddy humor.Ryder creates bizarre rhymes that tie together junk culture, drug lingo, literary references, and utter nonsense.EP, Radio Iodine, on Radioactive Records in November of 1996.When Cyclefly's debut album, Generation Sap, came out in 1999, the band's forceful yet melodic style of alternative rock was often described as a combination of Smashing Pumpkins, David Bowie, Jane's Addiction and Iggy Pop.And while all of those comparisons are valid and accurate, it's important to stress that Cyclefly is obviously striving for originality.Talking Head Jerry Harrison, Hutton benefits from the cutting guitar work of Joe Gore from P.Produced by Bobby Z with keyboard assists from Dr.Fink, both known for their work with Prince and the Revolution, AnaVoog.Named in honor of a crumbling Dublin housing estate, the edgy, assaultive Fatima Mansions formed in London in 1989.The group was led by the acerbic Cathal Coughlan, who first emerged with Microdisney, and completed by guitarist Andrias O'Gruama, bassist Hugh Bunker, drummer Nick Allum and keyboardist Zac Woolhous.Live, who have sold more than 20,000,000 albums worlwide, rose to chart success on the strength of its anthemic music and idealistic, overtly spiritual songwriting, two hallmarks which earned the group frequent comparisons to U2.After losing an area talent contest, they decided to enlist singer Ed Kowalczyk, and as a foursome the group played under a series of names including Public Affection before settling on Live.What Are We Fighting For?NRC does not regulate all sources of radioactivity; see Who Regulates Radioactive Materials and Radiation Exposure for details.For general information, see the How We Regulate page.Regulation of some activities associated with radioactive waste is covered under either the Nuclear Materials or Nuclear Reactors regulatory programs.See Uranium Milling under Fuel Cycle Facilities.
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