Soekarno Mulyorejo Surabaya — Telp. Enter a Name. Enter a valid Email. Message Message cannot be empty. Lecturer of Physics Dep.
Lecturer of Chemistry Dep. Lecturer of Biology Dep. Uranium and Its Uses. Nuclear Fuel Facts: Uranium. February 5. Accessed July 3, McClain, D. Miller, and J. Hammond, C. Lide, Boca Raton: CRC. World Nuclear Association. What is Uranium? Nor shall the RSC be in any event liable for any damage to your computer equipment or software which may occur on account of your access to or use of the Site, or your downloading of materials, data, text, software, or images from the Site, whether caused by a virus, bug or otherwise.
Jump to main content. Periodic Table. Glossary Allotropes Some elements exist in several different structural forms, called allotropes. Glossary Group A vertical column in the periodic table. Fact box. Glossary Image explanation Murray Robertson is the artist behind the images which make up Visual Elements.
Appearance The description of the element in its natural form. Biological role The role of the element in humans, animals and plants. Natural abundance Where the element is most commonly found in nature, and how it is sourced commercially. Uses and properties. Image explanation.
The image is based around the common astrological symbol for the planet Uranus. Uranium is a very important element because it provides us with nuclear fuel used to generate electricity in nuclear power stations. It is also the major material from which other synthetic transuranium elements are made. Uranium is the only naturally occurring fissionable fuel a fuel that can sustain a chain reaction. Uranium fuel used in nuclear reactors is enriched with uranium The chain reaction is carefully controlled using neutron-absorbing materials.
The heat generated by the fuel is used to create steam to turn turbines and generate electrical power. In a breeder reactor uranium captures neutrons and undergoes negative beta decay to become plutonium This synthetic, fissionable element can also sustain a chain reaction. Depleted uranium is uranium that has much less uranium than natural uranium. It is considerably less radioactive than natural uranium.
It is a dense metal that can be used as ballast for ships and counterweights for aircraft. It is also used in ammunition and armour. Biological role. Uranium has no known biological role. It is a toxic metal. Natural abundance. Uranium occurs naturally in several minerals such as uranite pitchblende , brannerite and carnotite.
It is also found in phosphate rock and monazite sands. World production of uranium is about 41, tonnes per year. Extracted uranium is converted to the purified oxide, known as yellow-cake. Uranium metal can be prepared by reducing uranium halides with Group 1 or Group 2 metals, or by reducing uranium oxides with calcium or aluminium.
Help text not available for this section currently. Elements and Periodic Table History. In the Middle Ages, the mineral pitchblende uranium oxide, U 3 O 8 sometimes turned up in silver mines, and in Martin Heinrich Klaproth of Berlin investigated it. He dissolved it in nitric acid and precipitated a yellow compound when the solution was neutralised. He realised it was the oxide of a new element and tried to produce the metal itself by heating the precipitate with charcoal, but failed.
The discovery that uranium was radioactive came only in when Henri Becquerel in Paris left a sample of uranium on top of an unexposed photographic plate. It caused this to become cloudy and he deduced that uranium was giving off invisible rays.
Radioactivity had been discovered. Atomic data. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom. Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey.
Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled. Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators.
Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Supply risk. Relative supply risk 5. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material.
Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate. Pressure and temperature data — advanced. Listen to Uranium Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry.
For Chemistry in its element this week, can you guess what connects boat keels, armour piercing weaponry, beautiful coloured glass that you can track down with a geiger counter and more oxidation states than a chemist can shake a glass rod at. If not, here's Polly Arnold with the answer. Uranium is certainly one of the most famous, or perhaps I should say infamous, elements.
It is the heaviest naturally occurring element. It is actually more abundant in the earth's crust than silver. It is one of eight elements named in honour of celestial objects, but you might not think that uranium deserves to be named after the planet Uranus.
The lustrous black powder that the chemist Klaproth isolated from the mineral pitchblende in - just eight years after Uranus was discovered - was in fact an oxide of uranium. Samples of the metal tarnish rapidly in air, but if the metal is finely divided, it will burst into flames.
Uranium sits amongst the actinides, the second shell of metals to fill their f-orbitals with valence electrons, making them large and weighty. Chemically, uranium is fascinating. Its nucleus is so full of protons and neutrons that it draws its core electron shells in close. This means relativistic effects come into play that affect the electron orbital energies.
The inner core s electrons move faster, and are drawn in to the heavy nucleus, shielding it better. So the outer valence orbitals are more shielded and expanded, and can form hybrid molecular orbitals that generated arguments over the precise ordering of bonding energies in the uranyl ion until as recently as this century.
This means that a variety of orbitals can now be combined to make bonds, and from this, some very interesting compounds. In the absence of air, uranium can display a wide range of oxidation states, unlike the lanthanides just above it, and it forms many deeply coloured complexes in its lower oxidation states. The uranium tetrachloride that Peligot reduced is a beautiful grass-green colour, while the triiodide is midnight-blue.
Because of this, some regard it as a 'big transition metal'. Most of these compounds are hard to make and characterise as they react so quickly with air and water, but there is still scope for big breakthroughs in this area of chemistry. The ramifications of relativistic effects on the energies of the bonding electrons has generated much excitement for us synthetic chemists, but unfortunately many headaches for experimental and computational chemists who are trying to understand how better to deal with our nuclear waste legacy.
In the environment, uranium invariably exists as a dioxide salt called the uranyl ion, in which it is tightly sandwiched between two oxygen atoms, in its highest oxidation state. Uranyl salts are notoriously unreactive at the oxygen atoms, and about half of all known uranium compounds contain this dioxo motif. One of the most interesting facets of this area of uranium chemistry has emerged in the last couple of years: A few research groups have found ways to stabilise the singly reduced uranyl ion, a fragment which was traditionally regarded as too unstable to isolate.
This ion is now beginning to show reactivity at its oxygen atoms, and may be able to teach us much about uranium's more radioactive and more reactive man-made sisters, neptunium and plutonium - these are also present in nuclear waste, but difficult to work with in greater than milligram quantities.
A person who weighs 70 kg has about g of potassium in his body which has activity of 4 kBq, most of which is located in the muscle. The absorbed dose per year is about 0. Upon ingestion, 40 K then moves quickly from the gastrointestinal track into the bloodstream. The 40 K quickly enters the bloodstream and distributed to all organs and tissues. Each year, this isotope delivers doses of about 18 millirem mrem to soft tissues of the body and 14 mrem to the bone.
The extraterrestrial radiations or cosmic radiations are high energetic radiations or subatomic particles, mainly originated from the sun, stars, collapsed stars such as neutron stars , quasars, and the hot galactic and intergalactic plasma. The earth and all living things on it are constantly bombarded by these radiations from space.
These radiations have extremely high energies that vary from 10 2 MeV to more than 10 14 MeV [ 16 ]. The cosmic radiations are much more intense in the upper troposphere. Cosmic radiation dose increases with altitude; at 2. Therefore, the annual effective doses from cosmic ray radiation around the world are estimated to range between 0.
The alpha and beta radiation emitted by these radioactive materials poses serious health threat if significant quantities are inhaled or injected.
In addition to natural background radiation, human beings are exposed to man-made radiation obtained from nuclear installations, nuclear explosions, nuclear fuel cycle, radioactive waste releases from nuclear reactor operations, and accidents and other industrial, medical, and agricultural uses of radioisotopes. The most significant sources of exposure, which gives the largest contribution to the public is from medical diagnostic X-rays, nuclear medicine, and nuclear therapy.
This is also generated from consumer products such as combustible fluids gas and coal , TV, luminous watches and dials, and electron tubes. The public are exposed to the radiation from the nuclear fuel cycle, which includes the entire sequence from mining and milling of uranium, the actual production of power at a nuclear power plant, and residual fallout from nuclear weapon testing and accident.
The public are not exposed to all the sources of radiation, for example, patients who are treated with the medical irradiation or the workers of nuclear industry may receive higher radiation exposure than the public [ 19 ].
The sources of radiation exposure in the United States were given in Figure 1. Sources of radiation exposure in the United States. The applications of radioisotopes have played a significant role in improving the quality of life of human beings.
The whole world is aware of the benefits of the radiation, but the phobia of nuclear weapons on Hiroshima and Nagasaki August 6 and 9, and the nuclear accidents occurred in Chernobyl in Russia April 25—26, and Fukushima in Japan March was so deep in the mind of the common man that we can still struggle to come out of it.
Major problems arrived by workers in nuclear fields are due to lack of legalization, shortage of resources, and knowledge about nuclear society and safe guards. Radiotracers are widely used in medicine, agriculture, industry, and fundamental research. Radiotracer is a radioactive isotope; it adds to nonradioactive element or compound to study the dynamical behavior of various physical, chemical, and biological changes of system to be traced by the radiation that it emits. The tracer principle was introduced by George de Hevesy in for which he was awarded the Nobel prize.
The sustainability of radioisotope production is one of the critical areas that receive great attention. There are more than different radioisotopes that are used regularly in different fields; these isotopes are produced either in a medium or in high-flux research reactors or particle accelerators low or medium energy [ 21 ].
Some of the radioisotopes produced by the reactor and particle accelerators and their applications are given in Table 4. Some of the radioisotopes produced by the reactor and particle accelerators and their applications. Nowadays radiotracer has become an indispensable and sophisticated diagnostic tool in medicine and radiotherapy purposes. The most common radioactivity isotope used in radioactive tracer is technetium 99 Tc. Tumors in the brain are located by injecting intravenously 99 Tc and then scanning the head with suitable scanners.
Kidney function is also studied using compound containing I. Tritium 3 H is frequently used as a tracer in biochemical studies. A most recent development is positron emission tomography PET , which is a more precise and accurate technique for locating tumors in the body.
A positron emitting radionuclide e. This technique is also used in cardiac and brain imaging. Compound X-ray tomography or CT scans. The radioactive tracer produces gamma rays or single photons that a gamma camera detects. Emissions come from different angles, and a computer uses them to produce an image. CT scan targets specific area of the body, like the neck or chest, or a specific organ, like the thyroid [ 22 ]. The most common therapeutic use of radioisotopes is 60 Co, used in treatment of cancer.
Sometimes wires or sealed needles containing radioactive isotope such as Ir or I are directly placed into the cancerous tissue. When the treatment is complete, these are removed. This technique is frequently used to treat mouth, breast, lung, and uterine cancer. Development of high yielding varieties of plants, oil seeds, and other economically important crops and protection of plant against the insects are the thrust area of agricultural research.
The irradiated seeds of wheat, rice, maize, cotton, etc. These varieties of crops are more disease resistant and have high yields. Several countries all over the world produce new variety of crops from radiation-induced mutants [ 23 ]. The best technique for the control of insects and pests is sterile insect technique SIT. Irradiation is used to sterilize mass-reared insects so that, while they remain sexually competitive, they cannot produce offspring.
As a result, it enhances the crop production and preservation of natural resources. Food irradiation has more advantages than conventional methods. All types of radiations are not recommended for food irradiation; only three types of radiation are recommended by CODEX general standard for food irradiation which are 60 Co or Cs, X-rays, or electron beams from particle accelerators [ 24 ]. No radiation remains in the food after treatment. This not only conserves energy but also prevents sweetening of potato, commonly occurring at low temperatures.
It gives advantage to the manufacturers of chips as low-sugar potato gives desired lighter color to fries and chips. Irradiated fruits all kinds of mangoes of these at hard mature pre-climacteric stage at 0. These doses are also effective in destroying quarantine pests. Under ice, sea food such as fish and prawns, fish-like Bombay duck, pomfret, Indian salmon, mackerel, and shrimp can be stored for about 7—10 days. Studies have demonstrated that irradiation at 1—3 kGy followed by storage at melting ice temperatures increases its shelf-life nearly threefold.
Radiation treatment has been employed to enhance the shelf-life of intermediate moisture meat products. While transporting the spices, due to inadequate handling and processing conditions, spices get contaminated with insect eggs and microbial pathogens. When incorporated into semi-processed or processed foods, particularly, after cooking, the microbes, both spoilers and pathogens, in spices can outgrow causing spoilage and posing risk to consumers.
Many of the spices develop insect infestation during storage, and unscrupulous traders convert them into spice powders. A dose of 10 kGy brings about near sterility or commercial sterility while retaining the natural characteristics of spices. Irradiation at higher doses can also be employed for total sterilization of diets for immunocompromised patients, adventure sports, military, and astronauts. Radioisotopes are commonly used in industry for checking blocked water pipes and detecting leakage in oil pipes.
For example, small quantity of radioactive 24 Na is placed in a small enclosed ball and is allowed to move in pipe with water. The moving ball containing radioisotope is monitored with a detector. If the movement of ball stops, it indicates the blocked pipe. Similarly, radioisotope 24 Na is mixed with oil flowing in an underground pipe. With radiation detector, the radioactivity over the pipe is monitored. If there is a leakage place, the radiation detector will show large activity at that particular place.
Radioisotopes are also used to monitor fluid flow and filtration, detect leaks, and gauge engine wear and corrosion of process in equipment.
Radioactive materials are used to inspect metal parts and the integrity of welds across a range of industries. The titanium capsule is a radioactive isotope which is placed on one side of the object being screened, and some photographic film is placed on the other side. The gamma rays pass through the object and create an image on the film.
Gamma rays show flaws in metal castings or welded joints. The technique allows critical components to be inspected for internal defects without damage. Radiotracer is also used to inspect for internal defect without damage. In industries, the production methods need to be constantly monitored in order to check the quality of products and to control the production process.
The monitoring is carried out by quality control devices using the unique properties of radiation; such devices are called nuclear gauges. They are more useful in extreme temperature, harmful chemical process, molten glass, and metals. The gauges are also used to measure the thickness of sheet materials, including metals, textiles, paper, and plastic production. Radiation passing through the material breaks the bonds by removing the electron of an atom or molecules; this induces physical, chemical, and biological changes.
Ionizing radiation focuses large amount of energy into a highly localized areas of irradiated materials. Damage is caused by the interaction of this energy with nuclei or orbiting electrons. The material structure may be modified through this energy interaction; as a result the mechanical property of bulk material changes. Radiation creates a point defect in metals; this had been recognized by Wigner in The radiation effects on metals depend on type and duration of the radiation.
Ionizing radiation can affect the metal in two ways, 1 lattice atoms are removed from their regular lattice sites, that is, displacement damage production and 2 chemical composition of the target can be changed by ion implantation or transmutation. Neutron-irradiated metals at room temperature show increase in electrical and thermal resistance, hardness, and tensile strength and higher yield strength along with decrease ductility in metals [ 25 ].
At higher temperature it is found that the strength and ductility return to the same values as before irradiation. A metal under stress at higher temperature exhibits the phenomenon of creep, that is, the gradual increase in strain with time. The thermal neutrons have less significant effect on the mechanical properties of metals.
They can be captured by nuclei of irradiated material which will become radioactive. Radiation causes the viscosity of oil and grease to increase as gummy, tar-like polymers are formed.
Radiation causes soap-oil-type greases to become more fluid. Plastics undergo drastic changes when exposed to radiation. The rubber may become harder or softer depending on its types. Concrete under radiation exposure heats up. This drives the water out of its internal structure.
Swelling, cracking, and spalling result [ 25 ]. Ionizing radiation can alter the molecular structure and macroscopic properties of the polymer. These processes in the target molecules lead to breaking of original bonds, production of ionized and excited species, bond rearrangement, chain scission, radical formation, etc.
All these processes are responsible for the modification of chemical, electrical, mechanical, and optical properties of polymers leading to their applications in different scientific and technological fields [ 25 ]. During radiation polymerization, the interaction takes place between two free radical monomers which combine to form intermolecular bond leading to three-dimensional network of cross-linked high molecular polymer. These cross-linked polymers show high thermal resistance and strong mechanical strength [ 26 ].
Grafting is a method wherein monomers are covalently bonded modified onto the polymer chain. This method involves the formation of free radical sites near the surface of polymers on to the polymeric backbone as a result of irradiation.
Hence microenvironment suitable for the reaction among monomer or polymer and the active site is formed, leading to propagation to form side chain grafts. The radiation-induced grafting is used in variety of applications such as biomedical, environmental, and industrial uses [ 26 , 27 , 28 ]. The radiation grafting can be performed by two major methods: pre-irradiation technique and mutual or simultaneous method [ 29 ].
Radiation-induced degradation technology is a new application to develop viscose, pulp, paper, food preservation, pharmaceutical production, and natural bioactive agent industries. Controlling the degree of degradation of polymers in industries is very important. Irradiation of polymers induces molecular chain branching, cross-linking, and molecular degradation or scissioning. Chain branching increases the molecular weight of the polymer.
Cross-linking forms the insoluble three-dimensional polymer network, while degradation or scissioning causes a reduction of initial molecular weight [ 30 , 31 ]. The polymer irradiated in air by solar radiation results in the formation of free radicals and can also react with oxygen, giving rise to oxidative degradation. All these molecular modifications can modify the properties of polymers. The study of degradation of polymer is important in using polymeric materials in radioactive environments such as in nuclear power plants, space, or the sterilization of polymeric medical disposals or food plastic packaging [ 32 ].
The splitting of polymeric macromolecules to form free radicals is employed for synthesizing modified polymers. At the same time, polymer degradation may often be considered as an undesirable side reaction occurring during the chemical transformation, fabrication, and usage of polymers.
The harmful effects that are produced in human beings who are exposed to radiations are called health effects. The result of all the physical interaction processes between incident radiation and the tissue of a cell is a trail of ionized atoms and molecules. The radiation is directly interacting with sensitive critical sites of the tissue DNA to produce damage by breaking chemical bonds.
The chemically active free radicals are indirectly produced by interaction of primary radiation with DNA of the tissue. Both direct and indirect damages produced in DNA by radiation are shown in Figure 2. The mechanism by which damage occurs in the cell by direct and indirect action of radiation. Radiation attacks DNA molecule directly Figure 2 ; as a result the ionization is produced and the bond is disrupted within a few nanometers of the DNA molecule.
Free radicals are important since they can diffuse far enough to reach and induce chemical changes at critical sites in biological structures.
The chemical damage produced by the breaking of DNA by the action of free radicals. The formation and action are as follows:. Ionization of a water molecule produces a free electron and a positively charged molecule:. The released electron is most likely to be captured by another water molecule converting it into a negative ion:.
Formation of free radicals is denoted by OH 0 and H 0. These free radicals interact with organic biomolecules RH again to produce organic free radicals denoted by R 0 :.
These free radicals interact with DNA to produce the damage. If double strand breaks the repair of the cell is not possible; as a result mutations or changes in DNA code this leads to a cell death or cancer. To a certain extent, these molecules are repaired by natural biological processes, and this ability to self-heal or self-repair depends on the extent of damage.
The biological effect of radiation on living cell may result in three outcomes: Death of the cells. A permanent alteration of the cell which is transmitted to later generation, that is, genetic effect. Oxygen effect is another effect produced by organic free radicals. The amplification of the Chemical action of free radicals due to the presence of oxygen in tissue is called oxygen effect. It has consequences that irradiated cell have a lower chance of survival in tissue rich in oxygen than in tissue less rich in oxygen.
Biological effects of radiation are broadly classified into deterministic effect and stochastic effects. These effects of damage from the radiation can be long term or short term. The large amount of radiation which is exposed to short interval of time is called acute radiation effects.
Small amount of radiation dose exposed to longer period is called delayed effect or chronic effect. Deterministic effects are severe, if dose exceeds a threshold level mSv. The severity of these effects in an exposed individual increases with the dose above the threshold as shown in Figure 3 b. The acute effect above the threshold at different time intervals is given Table 5.
Deterministic effect and stochastic effects of radiation.
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