| 释义 | 
		Definition of radioactivity in English: radioactivitynoun ˌreɪdɪəʊakˈtɪvɪtiˌreɪdioʊækˈtɪvədi mass noun1The emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei.  Example sentencesExamples -  In the first five years, the reactors will undergo mild surface-level deactivation to minimize their radioactivity.
 -  Their temperature ranges between 27°C and 51°C and they vary in radioactivity and fluorine content.
 -  Each appropriate region was scraped individually and radioactivity was determined in a scintillation counter.
 -  The results also point the way to the first direct measurements of the total radioactivity of the earth.
 -  The becquerel is a unit of radioactivity and corresponds to one radioactive disintegration per second.
 -  The Curies resolved to learn as much as they could about the source of radioactivity in pitchblende, the ore with which Becquerel originally worked.
 -  Pierre and Marie Curie called Becquerel's radiation radioactivity.
 -  When this occurs, the electron shoots out of the atom and is called a beta particle, a type of radioactivity.
 -  This year is the centennial of the Nobel Prize in Physics shared by Henri Becquerel and the Curies for their pioneering work on radioactivity.
 -  The element itself was actively producing radiation, a property referred to as radioactivity.
 -  TL is based on the continual accumulation of stored energy as a function of natural radioactivity.
 -  What makes dirty bombs particularly troublesome is that radioactivity, like fire, is something we deal with on a daily basis.
 -  Indeed, many isotopes spontaneously convert to other elements through radioactivity.
 -  In 1899 he identified two forms of radioactivity, which he called alpha and beta particles.
 -  The idea that radioactive isotopes can be used for dating purposes is almost as old as Henri Becquerel's discovery of radioactivity itself in 1896.
 -  A station opened in the Chatham Islands to monitor radioactivity, will help police the worldwide ban on Nuclear Weapons Testing.
 -  The Bequerel is a unit of radioactivity, which is equivalent to the number of radioactive particles detected per second.
 -  They may also interact with nonmedical regulations, such as limits on electromagnetic emissions or radioactivity.
 -  The time interval needed to reduce the applied radioactivity to 50% was taken as the optimal pulsing time.
 -  Early studies of radioactivity revealed that certain atomic nuclei were naturally radioactive.
 
 - 1.1 Radioactive substances, or the radiation emitted by these.
 an escape of radioactivity  Example sentencesExamples -  He is one of nine authorities which have been supplied with the latest equipment for recording and detecting radioactivity after an atomic bomb explosion.
 -  Cattle seem to absorb less radioactivity than sheep, except for the milk, which is to be avoided at all costs because of the iodine.
 -  No access to the core is possible because of the levels of radioactivity, continuing high temperatures inside and fears about its stability.
 -  The 60 cities with federally reported dietary levels of radioactivity are often not proximate to nuclear sites.
 -  Small amounts of radioactivity escaped into the atmosphere.
 -  It is suspected that workers have brought home tiny particles of radioactivity attached to their clothing or their skin.
 -  So sensitive is the detector that a single speck of dust within it could emit enough natural radioactivity to queer the readings.
 -  One example he gave was the leakage of radioactivity from Sellafield caused by pigeons.
 -  The lack of safeguards is leaving thousands of children across central Scotland at risk of thyroid cancer following an escape of radioactivity.
 -  The most common ill effects of exposure to radioactivity result from the ionization of water molecules by the radiation.
 -  The accident, which didn't cause any leakage of radioactivity, occurred when the train was reversing at just 5mph.
 -  Scientists can compare the number of breakdowns in any given time and the intensity of the radioactivity among elements and isotopes.
 -  The NRC says, even if a plane did attack a nuclear plant the likelihood of releasing radioactivity is low.
 -  The devices could be equipped with sensors that detect various substances, from heat to chemicals or radioactivity.
 -  Its functions relate principally to the monitoring of radioactivity in the environment and of radiation doses received by Irish people in the course of their work.
 -  The technique is based on the detection of radioactivity emitted after a small amount of a radioactive tracer is injected into a peripheral vein.
 -  They are comparing sediment taken from the Humber estuary - unpolluted by radioactivity - with other samples which contain the substance.
 -  Over the six decades of the lab's operation, radioactivity has leaked in unknown quantities into the water and vegetation surrounding the facility.
 -  Similar dangers exist of a structural collapse leading to an uncontrollable release of energy which could release radioactivity, he said.
 -  In the event of slow release of radioactivity it would be particularly important that medical personnel could recognise and diagnose the early effects of radiation.
 
  
    Definition of radioactivity in US English: radioactivitynounˌrādēōakˈtivədēˌreɪdioʊækˈtɪvədi 1The emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei.  Example sentencesExamples -  In 1899 he identified two forms of radioactivity, which he called alpha and beta particles.
 -  Pierre and Marie Curie called Becquerel's radiation radioactivity.
 -  The Bequerel is a unit of radioactivity, which is equivalent to the number of radioactive particles detected per second.
 -  What makes dirty bombs particularly troublesome is that radioactivity, like fire, is something we deal with on a daily basis.
 -  When this occurs, the electron shoots out of the atom and is called a beta particle, a type of radioactivity.
 -  This year is the centennial of the Nobel Prize in Physics shared by Henri Becquerel and the Curies for their pioneering work on radioactivity.
 -  The Curies resolved to learn as much as they could about the source of radioactivity in pitchblende, the ore with which Becquerel originally worked.
 -  Each appropriate region was scraped individually and radioactivity was determined in a scintillation counter.
 -  Early studies of radioactivity revealed that certain atomic nuclei were naturally radioactive.
 -  Their temperature ranges between 27°C and 51°C and they vary in radioactivity and fluorine content.
 -  TL is based on the continual accumulation of stored energy as a function of natural radioactivity.
 -  They may also interact with nonmedical regulations, such as limits on electromagnetic emissions or radioactivity.
 -  Indeed, many isotopes spontaneously convert to other elements through radioactivity.
 -  In the first five years, the reactors will undergo mild surface-level deactivation to minimize their radioactivity.
 -  The element itself was actively producing radiation, a property referred to as radioactivity.
 -  The time interval needed to reduce the applied radioactivity to 50% was taken as the optimal pulsing time.
 -  The becquerel is a unit of radioactivity and corresponds to one radioactive disintegration per second.
 -  The results also point the way to the first direct measurements of the total radioactivity of the earth.
 -  A station opened in the Chatham Islands to monitor radioactivity, will help police the worldwide ban on Nuclear Weapons Testing.
 -  The idea that radioactive isotopes can be used for dating purposes is almost as old as Henri Becquerel's discovery of radioactivity itself in 1896.
 
 - 1.1 Radioactive substances, or the radiation emitted by these.
 an escape of radioactivity  Example sentencesExamples -  It is suspected that workers have brought home tiny particles of radioactivity attached to their clothing or their skin.
 -  Its functions relate principally to the monitoring of radioactivity in the environment and of radiation doses received by Irish people in the course of their work.
 -  Small amounts of radioactivity escaped into the atmosphere.
 -  The devices could be equipped with sensors that detect various substances, from heat to chemicals or radioactivity.
 -  Similar dangers exist of a structural collapse leading to an uncontrollable release of energy which could release radioactivity, he said.
 -  He is one of nine authorities which have been supplied with the latest equipment for recording and detecting radioactivity after an atomic bomb explosion.
 -  No access to the core is possible because of the levels of radioactivity, continuing high temperatures inside and fears about its stability.
 -  In the event of slow release of radioactivity it would be particularly important that medical personnel could recognise and diagnose the early effects of radiation.
 -  One example he gave was the leakage of radioactivity from Sellafield caused by pigeons.
 -  The most common ill effects of exposure to radioactivity result from the ionization of water molecules by the radiation.
 -  Scientists can compare the number of breakdowns in any given time and the intensity of the radioactivity among elements and isotopes.
 -  They are comparing sediment taken from the Humber estuary - unpolluted by radioactivity - with other samples which contain the substance.
 -  Over the six decades of the lab's operation, radioactivity has leaked in unknown quantities into the water and vegetation surrounding the facility.
 -  Cattle seem to absorb less radioactivity than sheep, except for the milk, which is to be avoided at all costs because of the iodine.
 -  The NRC says, even if a plane did attack a nuclear plant the likelihood of releasing radioactivity is low.
 -  The technique is based on the detection of radioactivity emitted after a small amount of a radioactive tracer is injected into a peripheral vein.
 -  The 60 cities with federally reported dietary levels of radioactivity are often not proximate to nuclear sites.
 -  The lack of safeguards is leaving thousands of children across central Scotland at risk of thyroid cancer following an escape of radioactivity.
 -  The accident, which didn't cause any leakage of radioactivity, occurred when the train was reversing at just 5mph.
 -  So sensitive is the detector that a single speck of dust within it could emit enough natural radioactivity to queer the readings.
 
  
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