Radioactivity atraviesa.Una ionized medium than it is the neutron, which has no charge, but ionizes the matter indirectly. In radioactive decays have various types of radiation: alpha, beta, gamma and neutrons.
Radioactivity is a property of the isotopes that are "unstable", ie, that remain in an excited state in their electronic and nuclear layers, so that to reach its ground state, they must lose energy. They do electromagnetic emissions or particulate emissions with a certain kinetic energy. This occurs by varying the energy of its electrons (emitting X-rays) or its nucleons (gamma ray) or by varying the isotope (the output from the core electrons, positrons, neutrons, protons or heavier particles), and in several successive steps , which a heavy isotope can develop into a much lighter, such as uranium, with the passing of centuries, becoming just lead.
The radioactivity is used to obtain nuclear energy is used in medicine (radiation therapy and diagnostic radiology) and industrial applications (measurements of thicknesses and densities, etc.).
The radioactivity can be:
Natural: manifested by the isotopes found in nature.
Artificial or induced, expressed by the radioisotopes produced in artificial transformations.
Classes and components of radiation
Kinds of ionizing radiation and how to stop it.
Alpha particles (helium nuclei) are stopped by bringing a piece of paper. Beta particles (electrons and positrons) can not pass through a layer of aluminum. However, gamma rays (high energy photons) need a much thicker barrier, and the more energy can penetrate lead.
It was found that radiation can be of three different classes, known as particle decays and radiation:
Alpha particle: They are positively charged particles flows consist of two protons and two neutrons (helium nuclei). Are deflected by electric and magnetic fields. They are a little sharp, but very ionizing. They are very energetic. They were discovered by Rutherford, who posed as alpha particles through a thin glass and trapped in a discharge tube. This type of radiation emitted nuclei of heavy elements near the end of the periodic table (A> 100). These cores have many protons and the electric repulsion is very strong, so you tend to get N approximately equal to Z, and for that emits an alpha particle. In the process shows a lot of energy, which is converted into kinetic energy of the alpha particle, so that these particles come out with very high speeds.
Beta decay: They are flows of electrons (negative beta) and positrons (positive beta) resulting from the decay of neutrons or protons in the nucleus when it is in an excited state. Is deflected by magnetic fields. Is more pervasive, although the ionization power is not as high as that of alpha particles. Therefore, when an atom ejects a beta particle, its atomic number increases or decreases one unit (due to the proton won or lost). There are three types of beta radiation, beta radiation, "which is the spontaneous emission of electrons from the nuclei, the beta radiation +, in which a proton from the nucleus disintegrates and gives rise to a neutron, a positron or Beta + particle and a neutrino, and finally the electron capture that occurs in nuclei with excess protons, in which the nucleus captures an electron from the electronic bark, which is attached to a proton to give a neutron core.
Gamma radiation: It is electromagnetic waves. This is the most penetrating radiation.When electromagnetic waves of short wavelengths have greater penetration and requires very thick layers of lead or concrete to stop them. In this type of radiation does not lose its core identity, but it is clear from the energy left over to move to another lower energy state by emitting gamma rays, or high-energy photons. This type of emission accompanies alpha and beta. Because it is so pervasive and so energetic, it is the most dangerous type of radiation.
The laws of radioactive decay, described by Frederick Soddy and Kasimir Fajans, are:
When a radioactive atom emits an alpha particle, the mass of the atom (A) resulting decrease by 4 units and the atomic number (Z) 2.
When a radioactive atom emits a beta particle, the atomic number (Z) increases or decreases in one unit and the atomic mass (A) remains constant.
When an excited nucleus emits gamma radiation does not vary its mass and atomic number: only loses an amount of energy hν (where h is Planck's constant and "ν" is the frequency of the radiation).
The first two laws indicate that when an atom emits an alpha or beta radiation, is transformed into another atom of a different element. This new radioactive element can be transformed into another, and so on, with calls generated radioactive series.
Do you know how it affects us Nuclear Radiation?
Posted on March 15, 2011 by cubaout | 22 comments
Today has changed my life in Japan. People begin to have the suspicion that they have a problem, and this is radiation. Leaks and explosions of nuclear plants let out radioactive particles into the atmosphere. These affect us, take many years to be eliminated and the important thing is that the levels of radiation received accumulate in our bodies. It is measured in roentgen and everyone in risk areas should carry a portable meter that will indicate what he received radiation and the level is acceptable, or critical. This article prepared by CNN fayerwayer.com and information makes it clear the details of any good relationship between Man and nuclear radiation. Otto Grotten to cubaout.
Radiation Effects on Health. Although not yet reached levels of disaster, the problems in the Fukushima nuclear plant in Japan have been warning the world about the possibility of a radiation leak that could affect human health. What exactly are the risks? Why is there so much fear?
Radiation
Atoms can become radioactive when they are unstable. Elements such as uranium, which are commonly used in nuclear plants are not stable in nature and are always radioactive. In this state, the nuclei of atoms undergo a process of disintegration, during which much energy is released. This energy including gamma rays, neutrons, electrons and alpha and beta particles that are shot through space.
Depending on the dose of radiation received by the person, the effect can range from slight damage to the skin, vomiting, falling into a coma and even death. The radiation damages the DNA of cells, can have effects such as mutations or cause cancer. Some of this damage can be recovered, while other times not.
The radiation does not affect everyone the same way, and the effect is determined by the dose, exposure time and distance to the source of radiation.
What is the material coming out of the plant in Fukushima, and what they do?
Various nuclear fuels can produce different radioactive elements to different toxic effects. At the moment it is believed that gases like xenon and krypton would be released, along with isotopes of iodine 131, cesium, strontium, tellurium and rubidium.
Xenon and krypton are not absorbed by the body, so they have little effect on health.However, iodine and cesium are the most damaging itself.
Human thyroid absorbs iodine to make hormones. If the gland begins to absorb iodine 131, which emits beta rays can damage the DNA causing thyroid cancer. After the disaster at Chernobyl in Ukraine in 1986, more than 6,000 people developed thyroid cancer, probably from drinking contaminated milk as children. For some unknown reason, iodine 131 does not seem to affect adults.
The Japanese authorities distributed iodine tablets to children with this emergency. The idea is to saturate the thyroid of this element so that it does not absorb radioactive iodine.
On the other hand we have to cesium 137, which is much harder to eradicate than iodine. Ambient levels of this element are still high in Europe after Chernobyl. In some parts of England is not allowed to eat sheep, while other parties can not eat the mushrooms. Exposure to cesium was not directly related to a specific health problem, although it can cause nausea, vomiting, bleeding and cell damage depending on the concentration and exposure time.
Strontium, in turn, is absorbed by the body like calcium and is deposited in bones for years, irradiating the body from the inside, causing cancer or other health problems.
Other isotopes can take thousands of years to disappear from the environment, contaminating land in that time, animals and plants, making it one of the worst effects of these accidents.
Those who are most at risk at this time are the workers of the plant in Fukushima, which are very close to the source of radiation and could be seriously affected by it. The rest of the population has been evacuated to safe distances.
How is radiation?
The radioactivity is measured in terms of how many atoms spontaneously disintegrate every second. Various instruments have been developed to detect different types of radiation.
When it comes to exposure to radiation, the unit of measure used are sieverts, which measure the biological effect in the body.
Humans have always been exposed to radioactivity from the environment, whether natural or artificial sources. On average, a person receives between 2.4 and 10 mSv per year by cosmic rays, the sun and others. A person working with radioactive material receives an average of 50 mSv of radiation. X-ray radiography impacts with 0.02 mSv, whereas a CT adds 8 mSv. None of these tests takes a long time - with more prolonged exposure might be more dangerous.
Also, although high doses of radiation can cause cancer, cancer therapy using high-dose radiation, but focused on tumors and for a short time.
It is still too early to tell what effect the release of radiation Fukushima, since they are not still very clear the levels in the atmosphere and do not know yet what the outcome of the crisis that is going on the ground .
Sources: www.fayerwayer.com, CNN and New Scientist
This entry was posted on Cuban News, Economic News, News Spain, Latin American News, News Mexico, Venezuela News, Weather, Weather, Disasters, U.S. and Cuban American and labeled nuclear power plants, effects, Japan, Note, hazards, radiation,roentgen, health. Bookmark the permalink
As we are affected by radioactivity?
Today has changed my life in Japan. People begin to have the suspicion that they have a problem, and this is radiation. Leaks and explosions of nuclear plants let out radioactive particles into the atmosphere. These affect us, take many years to be eliminated and the important thing is that the levels of radiation received accumulate in our bodies. It is measured in roentgen and everyone in risk areas should carry a portable meter that will indicate what he received radiation and the level is acceptable, or critical. This article prepared by CNN fayerwayer.com and information makes it clear the details of any good relationship between Man and nuclear radiation. Otto Grotten to cubaout.
Radiation Effects on Health. Although not yet reached levels of disaster, the problems in the Fukushima nuclear plant in Japan have been warning the world about the possibility of a radiation leak that could affect human health. What exactly are the risks? Why is there so much fear?
Radiation
Atoms can become radioactive when they are unstable. Elements such as uranium, which are commonly used in nuclear plants are not stable in nature and are always radioactive. In this state, the nuclei of atoms undergo a process of disintegration, during which much energy is released. This energy including gamma rays, neutrons, electrons and alpha and beta particles that are shot through space.
Depending on the dose of radiation received by the person, the effect can range from slight damage to the skin, vomiting, falling into a coma and even death. The radiation damages the DNA of cells, can have effects such as mutations or cause cancer. Some of this damage can be recovered, while other times not.
The radiation does not affect everyone the same way, and the effect is determined by the dose, exposure time and distance to the source of radiation.
What is the material coming out of the plant in Fukushima, and what they do?
Various nuclear fuels can produce different radioactive elements to different toxic effects. At the moment it is believed that gases like xenon and krypton would be released, along with isotopes of iodine 131, cesium, strontium, tellurium and rubidium.
Xenon and krypton are not absorbed by the body, so they have little effect on health. However, iodine and cesium are the most damaging itself.
Human thyroid absorbs iodine to make hormones. If the gland begins to absorb iodine 131, which emits beta rays can damage the DNA causing thyroid cancer. After the disaster at Chernobyl in Ukraine in 1986, more than 6,000 people developed thyroid cancer, probably from drinking contaminated milk as children. For some unknown reason, iodine 131 does not seem to affect adults.
The Japanese authorities distributed iodine tablets to children with this emergency. The idea is to saturate the thyroid of this element so that it does not absorb radioactive iodine.
On the other hand we have to cesium 137, which is much harder to eradicate than iodine. Ambient levels of this element are still high in Europe after Chernobyl. In some parts of England is not allowed to eat sheep, while other parties can not eat the mushrooms. Exposure to cesium was not directly related to a specific health problem, although it can cause nausea, vomiting, bleeding and cell damage depending on the concentration and exposure time.
Strontium, in turn, is absorbed by the body like calcium and is deposited in bones for years, irradiating the body from the inside, causing cancer or other health problems.
Other isotopes can take thousands of years to disappear from the environment, contaminating land in that time, animals and plants, making it one of the worst effects of these accidents.
Those who are most at risk at this time are the workers of the plant in Fukushima, which are very close to the source of radiation and could be seriously affected by it. The rest of the population has been evacuated to safe distances.
How is radiation?
The radioactivity is measured in terms of how many atoms spontaneously disintegrate every second. Various instruments have been developed to detect different types of radiation.
When it comes to exposure to radiation, the unit of measure used are sieverts, which measure the biological effect in the body.
Humans have always been exposed to radioactivity from the environment, whether natural or artificial sources. On average, a person receives between 2.4 and 10 mSv per year by cosmic rays, the sun and others. A person working with radioactive material receives an average of 50 mSv of radiation. X-ray radiography impacts with 0.02 mSv, whereas a CT adds 8 mSv. None of these tests takes a long time - with more prolonged exposure might be more dangerous.
Also, although high doses of radiation can cause cancer, cancer therapy using high-dose radiation, but focused on tumors and for a short time.
It is still too early to tell what effect the release of radiation Fukushima, since they are not still very clear the levels in the atmosphere and do not know yet what the outcome of the crisis that is going on the ground .
Sources: www.fayerwayer.com, CNN and New Scientist
This entry was posted on Cuban News, Economic News, News Spain, Latin American News, News Mexico, Venezuela News, Weather, Weather, Disasters, U.S. and Cuban American and labeled nuclear power plants, effects, Japan, Note, hazards, radiation, roentgen, health. Bookmark the permalink.
http://cubaout.wordpress.com/2011/03/15/% C2% BFsabe-as-we-affects-the-radiation-nuclear /
After the natural disaster, in Japan the focus is now on the risk of nuclear disaster. The levels of radioactivity are not even harmful to people, but the fear of flying over the area.And fear, why?From the fission of uranium at a nuclear power plant releases more than 60 radioactive contaminants, of which iodine is one of the most harmful to human health."Within the radioactive emissions, is one of the most complicated to be very volatile," said Dr. Daniel Cragnolino, Chief of Nuclear Medicine, Hospital Universitario Austral (HUA). Chernobyl was released in huge amounts of iodine that ended the lives of tens of thousands of people in the short and long term. Iodine is the main source of radiation for humans.The target: the thyroid"You breathe the radioactive iodine, which, being highly volatile spreads quickly and easily through the air, this is fixed and destroys the thyroid gland, responsible for regulating body metabolism. Iodine, inside and outside the body, emits gamma rays, so it is said that "radiates". Their effects, most of the victims of a radioactive leak have hypothyroidism, thyroid cancer and leukemia, "summarized Dr. Cragnolino.Symptoms usually seen after a time depending on the proximity of the person in the area of the leak and the magnitude of this. Nuclear medicine expert described that "if they received a lethal dose of radiation at the time, there are pains, nausea, vomiting, bloody diarrhea, bleeding and hair loss groups. This painting is called acute radiation syndrome and is usually fatal. "In contrast, in the long term, especially those radiation affects cells "of rapid doubling" in the body, which comprises the blood cells, ova and sperm. Therefore, are common disorders such as anemia, neutropenia and sterility."Iodine tablets?Dr. Cragnolino stressed that Japan is distributing iodine tablets are among the evacuees from the area near the Fukushima reactor as a precaution. "The goal is to saturate the thyroid iodine does not absorb radioactive iodine from the air. Gland is blocked, "he said. However, people should wait for the flight to confirm the dose. "In Japan it is complying with all international safety standards and all safety precautions. A leak the size of the Chernobyl seems unlikely, "the specialist.Radiation comparedThe average person has accumulated a radiation dose of 2.5 millisieverts (mSv) per year.For an x-ray received from 0.2 to 0.7 mSv.For CT: 2 to 5 mSv.No medical procedure exceeds 10 mSv.Chernobyl: a lot of people who were in a radius of 30 km radius of the nuclear plant received more than 50 mSv (10%) and more than 100 mSv (5%).TypesRadiationAlpha Beta Gamma Propertyload 2 + 1-0mass 10-24g 6.64 x 9.11 x 0 10-28gPenetrating power 1 100 1000He nucleus nature Electron radiation of high energy photonsNuclidesThe term nuclide is assigned to a nucleus with a specific number of neutrons and protons, to the radioactive nuclei is called radionuclide atoms and these nuclei are called radioisotopes. However, the radionuclides are unstable due to the immense forces of various kinds operating in the core and particles and electromagnetic radiation emitted spontaneously. The emission of radiation is one of the ways in which an unstable nucleus is transformed into one that is more stable, with less energy.The most common types of decay are as already mentioned: Alpha radiation (), the Beta () and Gamma radiation ().The disintegration is carried out according to certain rules:• The number of nucleons (A) you must retain• The electric charge must be conserved• Energy must be conserved• The momentum must be conserved• The angular momentum (including spin angular momentum) should be retained.In the case of alpha radiation: This is the emission of a helium nucleus, ie two protons and two neutrons. For emitting isotope such particles, this issue will mean a decrease in two atomic mass units, ie losing two places in the location of the periodic table, on the other hand this also means the loss of four isotope units of its mass number.The Beta release: This is high-speed electrons emitted from an unstable nucleus. The particles are represented in equations by the symbol nuclear-1e or -1. The superscript 0 indicates that the electron mass is extremely small relative to the nucleon mass. The subscript -1 represents the particle charge. The emission b equals the conversion of a neutron (0n) into a proton (1p or 1H) which increases the atomic number 1.Gamma emissions or gamma decay: They are very little electromagnetic radiation wavelength. Its emission is caused by changes in energy within the nucleus. Its emission alone, no changes in the mass number or atomic number of nucleus.Sometimes there are excited states of nuclei in nuclear reactions and return to their ground state by emission of excess energy in the form of radiation:Example: [125Te] *125Te +The rays emitted by specific nuclei have a specific energy value or set of values defined energy because they corresponded to discrete energy levels of the nucleus. Thus, an emission spectrum of radiation is analogous to the line spectrum resulting from the transition of electrons between energy levels in an excited atom.How radioactivity affects us?
Radioactivity is the excitation energy (in the form of particles or electromagnetic radiation) that is released when an unstable atomic nucleus decays. These particles are able to interact with matter producing the ionization, meaning that they lose their energy, make substances that react with the acquired electrical charge by modifying its properties. Are more penetrating radiation, the lower this interaction, and will take longer to lose their energy, the most insightful are those Gamma, then the Alpha Beta and then, so the first two are the most commonly used in medical studies, as in cancer, not to produce serious disturbances. With regard to what he said peluq, radiation can cause ring opening and fragmentation of the nitrogenous bases, a situation which if not repaired, can lead to mutations in our genome.
