alpha rays

Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles (radiation). Decay is said to occur in the parent nucleus and produces a daughter nucleus. This is a random process, i.e. it is impossible to predict the decay of individual atoms. The SI unit for measuring radioactive decay is the becquerel (Bq). If a quantity of radioactive material produces one decay event per second, it has an activity of one Bq. Since any reasonably-sized sample of radioactive ...

Including:

• Radioactive decay - General introduction
• Radioactive decay - Discovery
• Radioactive decay - Modes of decay
• Radioactive decay - Decay chains and multiple modes
• Radioactive decay - Occurrence and applications
• Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia - Radioactive decay

The heaviest of the alkaline earth metals, radium is intensely radioactive and resembles Barium chemically. This metal is found (combined) in minute quantities in the uranium ore pitchblende, and various other uranium minerals. Radium preparations are remarkable for maintaining themselves at a higher temperature than their surroundings, and for their radiations, which are of three kinds: alpha rays, beta rays, and gamma rays. Radium ...

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Radium, Radium - Notable characteristics, Radium - Applications, Radium - History, Radium - Occurrence, Radium - Compounds, Radium - Isotopes, Radium - Radioactivity, Radium - Precautions

Read more here: » Radium: Encyclopedia II - Radium - Notable characteristics

Radioactivity was first discovered in 1896 by the French scientist Henri Becquerel while working on phosphorescent materials. These materials glow in the dark after exposure to light, and he thought that the glow produced in cathode ray tubes by X-rays might somehow be connected with phosphorescence. So he tried wrapping a photographic plate in black paper and placing various phosphorescent minerals on it. All results were negative until he tried using uranium salts. The result with thes ...

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Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - Discovery

Ionizing radiation - Natural background radiation. Natural background radiation comes from four primary sources: cosmic radiation, solar radiation, external terrestrial sources, and radon. The earth, and all living things on it, are constantly bombarded by radiation from outside our solar system of positively charged ions from protons to iron nuclei. This radiation interacts in the atmosphere to create secondary radiation that rains down, including x-rays, muons, protons, alpha particles, pions, electrons, and neutrons. The dose f ...

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Ionizing radiation, Ionizing radiation - Types of radiation, Ionizing radiation - Example: Electromagnetic radiation, Ionizing radiation - Sources of ionizing radiation, Ionizing radiation - Natural background radiation, Ionizing radiation - Man-made radiation sources, Ionizing radiation - The effects of ionizing radiation on animals, Ionizing radiation - Chronic radiation exposure, Ionizing radiation - Acute radiation exposure, Ionizing radiation - Radiation levels, Ionizing radiation - Minimizing health effects of ionizing radiation

Read more here: » Ionizing radiation: Encyclopedia II - Ionizing radiation - Sources of ionizing radiation

In 1896, Henri Becquerel was investigating phosphorescence in uranium salts when he discovered a new phenomenon which came to be called radioactivity. He, Pierre Curie and Marie Curie began investigating the phenomenon. In the process they isolated the element radium, which is highly radioactive. They discovered that radioactive materials produce intense, penetrating rays of several distinct sorts, which they called alpha rays, beta rays and gamma rays. Some of these kinds of radiation could pass through ordinary matter, and all of them could cause damage in large amounts - all the early researchers received various radiation burns ...

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Nuclear technology, Nuclear technology - History, Nuclear technology - Types of nuclear reaction, Nuclear technology - Major current applications

Read more here: » Nuclear technology: Encyclopedia II - Nuclear technology - History

According to the Big Bang theory, radioactive isotopes of the lightest elements (H, He, and traces of Li) were produced very shortly after the emergence of the universe. However, these structures are so highly unstable that virtually none of these original nuclides remain today. With this exception, all unstable nuclides were formed in stars (particularly supernovae). Radioactive decay has been put to use in the technique of radioisotopic labelling, used to track the passage of a chemical substance through a complex system (such as a ...

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Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - Occurrence and applications

Many radionuclides have several different observed modes of decay. Bismuth-212, for example, has three. The daughter nuclide of a decay event is usually also unstable, sometimes even more unstable than the parent. If this is the case, it will proceed to decay again. A sequence of several decay events, producing in the end a stable nuclide, is a decay chain. Of the commonly occurring forms of radioactive decay, the only one that changes the number of aggregate protons and neutrons (nucleons) contained in the nuclide is alpha emission, which reduces it by four. Thus, ...

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Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - Decay chains and multiple modes

Radionuclides can undergo a number of different reactions. These are summarized in the following table. A nucleus with charge (atomic number) Z and atomic weight A is represented as (A, Z). Radioactive decay results in a loss of mass, which is converted to energy (the disintegration energy) according to the formula E = mc2. This energy is ...

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Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - Modes of decay

The vast majority of everyday phenomena do not involve nuclear reactions. Most everyday phenomena only involve gravity and electromagnetism. Of the fundamental forces of nature, these are the weakest, but the strong nuclear force and the weak nuclear force are essentially short-range forces so they do not play a role outside the atomic nucleus. Atomic nuclei are generally kept apart because they contain positive electrical charges and therefore ...

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Nuclear technology, Nuclear technology - History, Nuclear technology - Types of nuclear reaction, Nuclear technology - Major current applications

Read more here: » Nuclear technology: Encyclopedia II - Nuclear technology - Types of nuclear reaction

The neutrons and protons that constitute nuclei, as well as other particles that may approach them, are governed by several interactions. 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. Of lesser importance is the weak nuclear force, and the gravitational force which has no influence on nuclear processes. The interplay of these forces is very complex. Some configurations of the particles in a nucleus have the pro ...

See also:

Radioactive decay, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - General introduction

Radium is over one million times more radioactive than the same mass of uranium. Its decay occurs in at least seven stages; the successive main products have been studied and were called radium emanation or exradio (this is radon), radium A (polonium), radium B (lead), radium C (bismuth), etc. (The radon is a heavy gas, the later products are solids.) These products are themselves radioactive elements, each with an atomic weight a little lower than its predecessor. Radium loses about 1% of its activity in 25 years, being transformed into elements of lower atomic weight with lead ...

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Radium, Radium - Notable characteristics, Radium - Applications, Radium - History, Radium - Occurrence, Radium - Compounds, Radium - Isotopes, Radium - Radioactivity, Radium - Precautions

Read more here: » Radium: Encyclopedia II - Radium - Radioactivity

Radium (Latin radius, ray) was discovered by Marie Curie and her husband Pierre in 1898 in pitchblende/uraninite from North Bohemia. While studying pitchblende the Curies removed uranium from it and found that the remaining material was still radioactive. They then separated out a radioactive mixture mostly consisting of barium which gave a brilliant red flame color and spectral lines which had never been documented before. In 1902 radium was isolated into its pure metal by Curie and Andre Debierne through the electrolysis of a pure radium chloride solution by using a mercury cathode and distilling ...

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Radium, Radium - Notable characteristics, Radium - Applications, Radium - History, Radium - Occurrence, Radium - Compounds, Radium - Isotopes, Radium - Radioactivity, Radium - Precautions

Read more here: » Radium: Encyclopedia II - Radium - History

As discussed above, the decay of an unstable nucleus (radionuclide) is entirely random and it is impossible to predict when a particular atom will decay. However, it is equally likely to decay at any time. Therefore, given a sample of a particular radioisotope, the number of decay events –dN expected to occur in a small interval of time dt is proportional to the number of atoms present. If N is the number of atoms, then the probability of decay (– dN/N) is proportional to dt: Rearranging, we obtain the following first ...

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Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - Decay timing

Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles (radiation). Decay is said to occur in the parent nucleus and produces a daughter nucleus. This is a random process, i.e. it is impossible to predict the decay of individual atoms. The SI unit for measuring radioactive decay is the becquerel (Bq). If a quantity of radioactive material produces one decay event per second, it has an activity of one Bq. Since any reasonably-sized sample of radioactive material contains very many atoms, one becquerel is a tiny level of activity; numbers on ...

See also:

Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - Headline text

Ionizing radiation is produced by radioactive decay, nuclear fission and nuclear fusion, extremely hot objects (thermal or blackbody radiation), and accelerated charges (bremsstrahlung or synchrotron radiation). In order for radiation to be ionizing, the particles must both have a high enough energy and interact with electrons. Photons interact strongly with charged particles, so photons of sufficiently high energy are ionizing (the energy at which this begins to happen is in the ultraviolet region; sunburn is one of the effects of th ...

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Ionizing radiation, Ionizing radiation - Types of radiation, Ionizing radiation - Example: Electromagnetic radiation, Ionizing radiation - Sources of ionizing radiation, Ionizing radiation - Natural background radiation, Ionizing radiation - Man-made radiation sources, Ionizing radiation - The effects of ionizing radiation on animals, Ionizing radiation - Chronic radiation exposure, Ionizing radiation - Acute radiation exposure, Ionizing radiation - Radiation levels, Ionizing radiation - Minimizing health effects of ionizing radiation

Read more here: » Ionizing radiation: Encyclopedia II - Ionizing radiation - Types of radiation

Although exposure to ionizing radiation carries a risk, it is impossible to completely avoid exposure. Radiation has always been present in the environment and in our bodies. We can, however, avoid undue exposure. Although people cannot sense ionizing radiation, there is a range of simple, sensitive instruments capable of detecting minute amounts of radiation from natural and man-made sources. Dosimeters measure an absolute dose received over a period of time. Ion-chamber dosimeters resemble pens, and can be clipped to one's cl ...

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Ionizing radiation, Ionizing radiation - Types of radiation, Ionizing radiation - Example: Electromagnetic radiation, Ionizing radiation - Sources of ionizing radiation, Ionizing radiation - Natural background radiation, Ionizing radiation - Man-made radiation sources, Ionizing radiation - The effects of ionizing radiation on animals, Ionizing radiation - Chronic radiation exposure, Ionizing radiation - Acute radiation exposure, Ionizing radiation - Radiation levels, Ionizing radiation - Minimizing health effects of ionizing radiation

Read more here: » Ionizing radiation: Encyclopedia II - Ionizing radiation - Minimizing health effects of ionizing radiation

We tend to think of biological effects of radiation in terms of their effect on living cells. For low levels of radiation exposure, the biological effects are so small they may not be detected. The body repairs many types of radiation and chemical damage. Biological effects of radiation on living cells may result in four outcomes: Injured or damaged cells repair themselves, resulting in no residual damage. Cells die, much like millions of body cells do every day, being replaced through normal biological processes. ...

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Ionizing radiation, Ionizing radiation - Types of radiation, Ionizing radiation - Example: Electromagnetic radiation, Ionizing radiation - Sources of ionizing radiation, Ionizing radiation - Natural background radiation, Ionizing radiation - Man-made radiation sources, Ionizing radiation - The effects of ionizing radiation on animals, Ionizing radiation - Chronic radiation exposure, Ionizing radiation - Acute radiation exposure, Ionizing radiation - Radiation levels, Ionizing radiation - Minimizing health effects of ionizing radiation

Read more here: » Ionizing radiation: Encyclopedia II - Ionizing radiation - The effects of ionizing radiation on animals

The energy of a photon (i.e., a quantum of electromagnetic radiation) is given by the Planck equation: E = hν where E is the energy of the photon h is Planck's constant ν is the frequency of the photon The wavelength of a photon is related to its frequency by the equation of a wave's v ...

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Ionizing radiation, Ionizing radiation - Types of radiation, Ionizing radiation - Example: Electromagnetic radiation, Ionizing radiation - Sources of ionizing radiation, Ionizing radiation - Natural background radiation, Ionizing radiation - Man-made radiation sources, Ionizing radiation - The effects of ionizing radiation on animals, Ionizing radiation - Chronic radiation exposure, Ionizing radiation - Acute radiation exposure, Ionizing radiation - Radiation levels, Ionizing radiation - Minimizing health effects of ionizing radiation

Read more here: » Ionizing radiation: Encyclopedia II - Ionizing radiation - Example: Electromagnetic radiation

The neutrons and protons that constitute nuclei, as well as other particles that may approach them, are governed by several interactions. 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. Of lesser importance is the weak nuclear force, and the gravitational force has no influence on nuclear processes. The interplay of these forces is very complex. Some configurations of the particles in a nucleus have the property ...

See also:

Radioactive decay, Radioactive decay - Headline text, Radioactive decay - General introduction, Radioactive decay - Discovery, Radioactive decay - Modes of decay, Radioactive decay - Decay chains and multiple modes, Radioactive decay - Occurrence and applications, Radioactive decay - Decay timing

Read more here: » Radioactive decay: Encyclopedia II - Radioactive decay - General introduction