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Nitrogen IsotopesRadiometric DatingCarbon IsotopesAtmosphereHistory, AncientNitrogenHairIsotopesIsotope LabelingDietOxygen IsotopesNitrogen FixationExtraterrestrial EnvironmentSaturnNitrogen CompoundsNitrogen CycleEarth (Planet)Encyclopedias as TopicNitrous OxideNitratesAerosol PropellantsOsmium TetroxideNitrogen Dioxide
Stable isotopeRadioactive isotope of carbonRadiocarbonProduced in the Earth's atmosphereRatiosAtmospheric nitrogenEarth's AtmospherePhosphorusUnstableProtonsAtoms in the atmosphereNeutrons strikeHydrogenBombardmentGeochemistryFractionationNeutronEmissionsNitrateTracersAmmoniumDecayCarbon monoxideScientistsRatio in the atmosphereNaturallyUpperSoilPlanet'sHeliumCompositionAtomFossil fuelCometsOrganismsParticlesSolarOrganicMoleculesCollideUreaLightestGreenhouseOrganismCombines with oxygen to formReactiveFertilizersBiosphereDioxideElementalMoleculeBiologicalGasesConcentrationBillions of years
Stable isotope3
  • The concentrations and nitrogen stable isotope composition of aerosol NH4+ (δ15N-NH4+) were both elevated during the five haze episodes that were sampled. (edu.hk)
  • This transforms it into Nitrogen-14, which is a stable isotope. (datingsidekick.com)
  • The Stable Isotope Ecology Laboratory of the Center for Applied Isotope Studies at the University of Georgia , offers a wide variety of analytical services to researchers associated with any bona-fide nonprofit research organization. (uga.edu)
Radioactive isotope of carbon1
  • Carbon-14 is a radioactive isotope of carbon, with 6 protons and 8 neutrons in its nucleus. (datingsidekick.com)
Radiocarbon13
  • Radiocarbon only occurs on Earth in trace amounts compared to the other naturally occurring carbon isotopes. (sciencealert.com)
  • When these rays enter the atmosphere, they interact with the local nitrogen atoms to trigger a nuclear reaction that produces radiocarbon. (sciencealert.com)
  • When Earth's magnetic field is weakened, as it was during the Laschamp event, more cosmic rays penetrate through to the atmosphere to produce more radiocarbon. (sciencealert.com)
  • Radiocarbon ( 14 C) is the natural radioactive carbon isotope, which is produced in the atmosphere by cosmic ray-induced reactions with atmospheric nitrogen. (uni-heidelberg.de)
  • Radiocarbon dating is a technique that uses the C-14 isotope to determine the age of fossils, wood, and animals. (moravek.com)
  • In the case of radiocarbon, for example, one must assume that the radiocarbon atoms in the seed came from a particular source-for example, the atmosphere-in the year the seed grew and was buried. (icr.org)
  • The seeds supposedly grabbed their radiocarbon atoms from very old water instead of from the ancient atmosphere. (icr.org)
  • What radiocarbon dating is produced by the atmosphere convert nitrogen into question after nitrogen-14. (turismolasnavas.es)
  • So we employed numerous scientific techniques including radiocarbon dating and beryllium isotope analysis . (aspioneer.com)
  • When neutrons, smashed off atoms by incoming cosmic rays, merge with nitrogen produces radiocarbon aka Carbon-14 in Earth's atmosphere. (craffic.co.in)
  • Brakenridge told The Register that these are small radiocarbon isotope anomalies, peaks in concentration, in tree rings at particular years as dated by tree-ring scientists. (craffic.co.in)
  • Radiocarbon dating, additionally known as carbon relationship, uses the unstable isotope carbon-14 (14C) and the secure isotope carbon-12 (12C). (lorobymilano.pl)
  • Radiocarbon relationship, also called carbon relationship, makes use of the unstable isotope carbon-14 (14C) and the secure isotope carbon-12 (12C). (eown.in)
Produced in the Earth's atmosphere2
Ratios7
  • They looked at data recorded by the Cassini-Huygens probe to better understand the isotopic ratios in Titan's dense, hazy atmosphere . (space.com)
  • Outgassing and collisional processing on both worlds led to the production of molecular nitrogen-dominated atmospheres with similar isotopic ratios of hydrogen, carbon, nitrogen and oxygen. (space.com)
  • Instead, they precisely measure carbon isotope ratios. (icr.org)
  • Experts must therefore convert the isotope ratios into "ages" using a series of formulas. (icr.org)
  • Measurements of isotopic ratios is an especially daunting undertaking, mainly because of the extreme weakness of the spectral signatures (emissions) of the less abundant species like carbon-13, nitrogen-15, etc. (eso.org)
  • In recent decades, the natural abundances of stable carbon and nitrogen isotopes (represented as 13 C/ 12 C and 15 N/ 14 N ratios, respectively) have been widely used to probe biogeochemical and ecological processes. (springeropen.com)
  • Primordial ratios', such as those seen in comets, are thought to be a record of the original isotope ratio of the parent body when it formed in the early stages of the Solar System. (europlanet-society.org)
Atmospheric nitrogen3
Earth's Atmosphere23
  • N2 forms about 78% of Earth's atmosphere, making it the most abundant uncombined element in air. (wikipedia.org)
  • Its atmosphere is often viewed as an analog to what the Earth's atmosphere may have been like billions of years ago. (space.com)
  • Trigo-Rodriguez and Martin-Torres believe the vital organic ingredients in the early Earth's atmosphere were vaporized and swept away by solar winds. (space.com)
  • Earth's atmosphere is resilient to many of the changes humans have imposed on it. (nasa.gov)
  • The resilience of Earth's atmosphere has been proven throughout our planet's climate history," said Crisp, science team lead for NASA's Orbiting Carbon Observatory-2 (OCO-2) satellite and its successor instrument, OCO-3, which launched to the International Space Station on May 4. (nasa.gov)
  • Earth's atmosphere is associated with many types of cycles, such as the carbon cycle and the water cycle. (nasa.gov)
  • The composition of Earth's atmosphere has most certainly been altered. (nasa.gov)
  • The concentration of carbon dioxide in Earth's atmosphere is currently at nearly 412 parts per million (ppm) and rising. (nasa.gov)
  • Unfiltered radiation from space ripped apart air particles in Earth's atmosphere, separating electrons and emitting light - a process called ionisation," Turney said . (sciencealert.com)
  • Where solar light is vertically incident, around 1,360 watts of power strike one square meter of the Earth's atmosphere. (phys.org)
  • Carbon dioxide has no liquid state at the pressures encountered in Earth's atmosphere. (skepticalscience.com)
  • Instead, at normal atmospheric pressures, it sublimes from solid to gas at −78 °C. Solid carbon dioxide is also known as dry ice, but cannot form in the range of temperatures found within Earth's atmosphere, although it is produced industrially for various purposes. (skepticalscience.com)
  • These gases, in turn, trap heat in the Earth's atmosphere, contributing to global warming and thereby altering the conditions under which food crops grow, affecting not only crop yields, but also food quality and food security. (iaea.org)
  • About 4/5ths of the air in Earth's atmosphere is nitrogen (N2). (windows2universe.org)
  • About four out of five of the molecules in Earth's atmosphere is nitrogen gas! (windows2universe.org)
  • Because living organisms breathe in and store carbon, any living organism takes in the same carbon mixture of the Earth's atmosphere to feature the exact amount of isotopes within its body. (moravek.com)
  • About 4/5ths of Earth's atmosphere is nitrogen gas! (windows2universe.org)
  • The universe provides clues to the history of Earth's atmosphere, a 100 kilometer-thick layer of many different gases that are kept close to Earth by gravity. (visionlearning.com)
  • Strangely enough, the element that has revealed much of what we know about the evolution of Earth's atmosphere is neon. (visionlearning.com)
  • Greek philosophers and medieval thinkers originally believed that this blanket of air consisted of a uniform substance, but 19th century scientists like John Dalton used a series of experiments to determine that it is actually a mixture of many different gases, primarily nitrogen, oxygen, and argon (see our module on The Composition of Earth's Atmosphere ). (visionlearning.com)
  • For example, Earth's atmosphere contains around 20 parts per million (abbreviated as ppm) of neon gas , the same gas used to produce the bright glow of restaurant signs and cinema marquees. (visionlearning.com)
  • Carbon dioxide is a byproduct exhaled by humans and makes up about 4% of the Earth's atmosphere. (factscrush.com)
  • The interaction between charged cosmic particles and air particles in Earth's atmosphere is also what creates auroras. (aspioneer.com)
Phosphorus2
  • In the 0-30 cm soil depth, SOM, total nitrogen (N), available phosphorus (P), exchangeable potassium (K) and pH varied significantly throughout the cultivation period. (researchgate.net)
  • We can also analyze soil samples for total nitrogen (TN), total phosphorus (TP) and a variety of metals and offer a variety of digestion and extraction techniques. (uga.edu)
Unstable5
  • Carbon comes in three isotopes, and the rarest of the three has an unstable nucleus. (icr.org)
  • In the first few lectures I mentioned that certain isotopes of certain elements were unstable and underwent radioactive decay. (ucsd.edu)
  • Atoms of this rare isotope of carbon, carbon-14, are unstable: they spontaneously turn back into nitrogen atoms over time. (actforlibraries.org)
  • Cosmic-ray bombardment of the gases high in the atmosphere is constantly creating these unstable atoms, but carbon-14 decays rather slowly. (actforlibraries.org)
  • Whether an isotope is stable or unstable makes no difference to a chemical reaction, so the percentage of carbon-14 atoms remains a constant even when the atoms become plugged into carbon dioxide or more complex molecules, such as sugar or protein. (actforlibraries.org)
Protons2
  • Carbon-14 (a carbon atom with six protons and eight neutrons) is an isotope of normal carbon, which is also known as carbon-12 (a carbon atom with six protons and six neutrons). (juniorsbook.com)
  • A tiny percentage of carbon atoms-about one in a trillion-starts out as a nitrogen atom, until one of its protons is turned into a neutron by a collision with a cosmic ray. (actforlibraries.org)
Atoms in the atmosphere2
Neutrons strike2
Hydrogen4
  • The human body contains about 3% nitrogen by mass, the fourth most abundant element in the body after oxygen, carbon, and hydrogen. (wikipedia.org)
  • Trigo-Rodriguez and Martin Torres studied how hydrogen, carbon, nitrogen and oxygen isotopes reacted with their environments on Earth and Titan. (space.com)
  • An isotope of hydrogen called "deuterium" has one proton plus one neutron in its nucleus. (windows2universe.org)
  • Coal is made of carbon and various other elements (hydrogen, nitrogen, oxygen and sulfur). (factscrush.com)
Bombardment2
  • Even so, both Earth and Titan were hit by similar water-rich bodies, which provided a volatile-rich source for both atmospheres during the late-heavy bombardment. (space.com)
  • It's formed in the upper atmosphere under the bombardment of cosmic rays from space. (sciencealert.com)
Geochemistry2
  • This course will examine the long-term record of global change as reflected in sedimentary rocks, fossil faunas and floras and low-temperature isotope geochemistry. (laurentian.ca)
  • Although the carbon and nitrogen isotopic compositions of diverse types of organic matter were measured and discussed by the pioneers of isotope geochemistry (e.g. (springeropen.com)
Fractionation1
  • After accounting for the isotope fractionation that occurs during gas-to-particle partitioning (17.7? (edu.hk)
Neutron1
  • While it might seem far-fetched to imagine Maasai pastoralists employing nuclear techniques to start agriculture in the arid landscape of East Africa, the Joint Division has supported KARI in developing low-cost, small-scale irrigation technologies based on the use of neutron probes and isotope tracers that are specifically designed to meet the needs of the Maasai. (iaea.org)
Emissions4
  • But it's constantly heading up into our atmosphere - in 2021 alone the figure for such emissions, according to the International Energy Agency, was 36,300,000,000 tonnes of the stuff. (skepticalscience.com)
  • These inhibitors are added to nitrogen fertilizers to reduce N 2 O emissions. (iaea.org)
  • These cubes provide spectral and spatial information on nitrogen emissions, H emission and absorption, absorption by simple hydrocarbons, and the scattering properties of haze aerosols. (esa.int)
  • What controls the atmospheric CO 2 and CH 4 variations and the partitioning of emissions between the atmosphere, the ocean and sinks in the biosphere? (lu.se)
Nitrate2
  • Alchemists knew nitric acid as aqua fortis (strong water), as well as other nitrogen compounds such as ammonium salts and nitrate salts. (wikipedia.org)
  • Most plutonium is found combined with other substances, for example, plutonium dioxide (plutonium with oxygen) or plutonium nitrate (plutonium with nitrogen and oxygen). (cdc.gov)
Tracers1
Ammonium1
  • Nitrogen compounds have a very long history, ammonium chloride having been known to Herodotus. (wikipedia.org)
Decay6
  • In an undisturbed steady state situation the atmospheric 14 CO 2 activity corresponds to an equilibrium between its production in the atmosphere and its radioactive decay in all carbon reservoirs exchanging CO 2 with the atmosphere. (uni-heidelberg.de)
  • Dating, carbon 14 of the ratio of prehistoric samples is another radioactive decay of an isotope of 5730 years. (turismolasnavas.es)
  • It uses the law of radioactive decay- C-14 isotopes decay over a specified period, allowing scientists to estimate the age accurately. (datingsidekick.com)
  • The rate of radioactive decay of a substance is defined by its half-life, that is, the time it takes for half the atoms in a radioactive isotope to decay. (juniorsbook.com)
  • Not only does the body decay, but the carbon-14 atoms decay as well - except that the carbon-14 atoms decay to nitrogen, and very slowly at that. (actforlibraries.org)
  • he half-life is the time it takes for half of the atoms of a radionuclide to undergo radioactive decay and change it into a different isotope. (cdc.gov)
Carbon monoxide2
  • The extremely strong triple bond in elemental nitrogen (N≡N), the second strongest bond in any diatomic molecule after carbon monoxide (CO), dominates nitrogen chemistry. (wikipedia.org)
  • Pollutants of major public health concern include particulate matter, carbon monoxide, ozone, nitrogen dioxide and sulfur dioxide. (who.int)
Scientists4
  • Those results excited and fascinated scientists because Mars - like all the other planets in our solar system - has an atmosphere that is remarkably different from Earth's. (visionlearning.com)
  • Although this noble gas forms just a tiny fraction of the modern atmosphere, it contains the clues scientists needed to decode the past. (visionlearning.com)
  • Carbon-14 is not the only radioactive isotope scientists can measure and use to date an artifact. (juniorsbook.com)
  • Before, the scientists thought that it was due to certain asteroids that bring the nitrogen on our planet during its first billion of years. (w3ask.com)
Ratio in the atmosphere2
  • We also need to assume a value for the carbon isotope ratio in the atmosphere at that time. (icr.org)
  • Since this exchange is constantly in progress, the ratio of carbon-14 atoms to all carbon atoms in a living organism's body stays the same as the ratio in the atmosphere. (actforlibraries.org)
Naturally4
  • The final group of contaminants that could be present in rainwater are radiologicals, specifically tritium, which is naturally produced in the upper atmosphere when cosmic rays collide with nitrogen atoms in the air. (wqpmag.com)
  • Naturally occurring radioactive isotope 14 remaining after a measure of this section we. (turismolasnavas.es)
  • Carbon-14 is a naturally occurring radioactive isotope . (datingsidekick.com)
  • Carbon-14 is radioactive and is produced naturally in the atmosphere when cosmic rays collide with nitrogen atoms. (juniorsbook.com)
Upper5
  • Ultraviolet light, for example, is almost entirely absorbed in the upper layers of the atmosphere. (phys.org)
  • Growing out of a collaboration between the University of Colorado Boulder and the University of California Berkeley, MAVEN is a New Frontiers mission which aims to understand how Mars' upper atmosphere is being lost to space and how this has impacted the evolution of the Martian climate over the history of the solar system. (newmars.com)
  • Are used to calculate the upper atmosphere is probably one of the use of the properties of korff's research has been one of old. (turismolasnavas.es)
  • It is made when cosmic rays hit nitrogen atoms in the upper atmosphere. (datingsidekick.com)
  • அண்டக் கதிர்வீச்சால் (Cosmic rays) பாதிப்படைந்த நைட்ரஜன் 14 ஐசோடோப்பு (Nitrogen 14 Isotope) மூலம் மேல் வளிமண்டலத்தில் (Upper atmosphere) ரேடியோ கார்பன் உற்பத்தியாகிறது. (arivoli.in)
Soil6
  • Increasing nitrogen efficiency in farming and stopping the escape of nitrogen from soil can therefore greatly contribute to climate change mitigation strategies. (iaea.org)
  • Therefore, more nitrogen can remain in the soil, minimizing the release of N 2 O. (iaea.org)
  • If too much is spread on the soil, the extra that is not taken up by the plant is released into the atmosphere as a greenhouse gas emission making it a climate hazard. (iaea.org)
  • If too much goes into the soil, nitrogen leaching can occur, which means that the excess drains through the soil and, if it reaches the level of the ground water, it can make the water unsuitable for human consumption. (iaea.org)
  • Soils store more carbon than the atmosphere and living biomass together, therefore are carbon compounds entering or leaving the soil C storage system of large importance for greenhouse effect mitigation. (lu.se)
  • To do so, we typically employ a range of isotope-based approaches which allow us to examine the microbial use and transformations of carbon and nitrogen in soil systems. (lu.se)
Planet's2
  • Oxygen is also the most abundant element by mass in Earth's crust, and the second most abundant gas (after nitrogen) in our planet's atmosphere. (windows2universe.org)
  • The difference between the two arose over 4.6 billion years of time in which each planet's atmosphere formed and changed because of that planet's unique characteristics and history. (visionlearning.com)
Helium4
  • Subsequent extraction and combustion of these fossil fuel reserves releases this helium isotope but historically, efforts to measure changes in the concentration of atmospheric helium have proven challenging owing to the low natural abundance of this gas. (chemistryworld.com)
  • Using mass spectrometry, a team surrounding Benjamin Birner and Ralph Keeling at the Scripps Institution of Oceanography in the US has been able to accurately quantify atmospheric helium for the first time by comparing levels of the 4 He isotope with nitrogen. (chemistryworld.com)
  • As nitrogen levels in the atmosphere remain constant, any change in the 4 He/N 2 ratio corresponds to a change in helium isotope levels. (chemistryworld.com)
  • However, previous studies have demonstrated that the ratio of the helium isotopes 3 He and 4 He has remained constant over this same period, meaning a corresponding increase in atmospheric 3 He must be occurring undetected. (chemistryworld.com)
Composition4
Atom3
  • An isotope is an atom of an element that has a different number of neutrons than the common, stable form of the element. (juniorsbook.com)
  • No matter where you are, if you were to select a carbon atom at random from the atmosphere, the probability that it is a carbon-14 atom is identical. (actforlibraries.org)
  • These three facts suggest that if you could separate every carbon atom from dead organic matter into little piles depending on the isotope, you could calculate the ratio of carbon atoms in your sample. (actforlibraries.org)
Fossil fuel3
  • A relative decline in the amount of heavy carbon-13 isotopes in the atmosphere points to fossil fuel sources. (nasa.gov)
  • The natural equilibrium level of atmospheric 14 CO 2 (reference level) has been disturbed through man's activities in the last century, by the ongoing input of fossil fuel CO 2 into the atmosphere known as Suess effect, and through nuclear bomb testing in the atmosphere in the 1950s and early 1960s ( 14 C bomb effect). (uni-heidelberg.de)
  • Today the decrease is mainly due to the ongoing input of 14C-free fossil fuel CO2 into the global atmosphere. (uni-heidelberg.de)
Comets3
  • Despite the 800 million miles between the two worlds, both may have had their atmospheres created through the gravitational layering and processing of asteroids and comets. (space.com)
  • The research paper, "Clues on the importance of comets in the origin and evolution of the atmospheres of Titan," by Trigo-Rodriguez and F. Javier Martin-Torres (Center for Astrobiology, Madrid, Spain), recently published in the journal Planetary and Space Science, offers insight into the atmospheric affinities of Earth and Titan. (space.com)
  • According to Chris McKay, a planetary scientist at NASA's Ames Research Center, comets may have made small contributions to the water, carbon dioxide, and nitrogen content of the Earth's early atmosphere, "but they were not the main source. (space.com)
Organisms3
  • This causes difficulty for both organisms and industry in converting N2 into useful compounds, but at the same time it means that burning, exploding, or decomposing nitrogen compounds to form nitrogen gas releases large amounts of often useful energy. (wikipedia.org)
  • Nitrogen occurs in all organisms, primarily in amino acids (and thus proteins), in the nucleic acids (DNA and RNA) and in the energy transfer molecule adenosine triphosphate. (wikipedia.org)
  • Carbon and nitrogen are essential elemental constituents of organisms and form various chemical species on Earth. (springeropen.com)
Particles2
  • The astronomers conclude that part of the cometary nitrogen is trapped in macromolecules attached to dust particles. (eso.org)
  • Sedimentary rocks never have particles that include radioactive isotopes. (lorobymilano.pl)
Solar5
  • During this period, oxygen- and volatile-rich materials from the outer solar system were hurled en masse towards the inner solar system. (space.com)
  • Nitrogen on Earth is a great mystery, in the sense that it is unique in the solar system. (w3ask.com)
  • Although they suggested any variation in the isotope is due to standard solar rays rather than dramatic explosions rather than finding solid evidence linking two changes. (craffic.co.in)
  • Only two possibilities are present for the explanation of the presence of isotope that is a solar flare or a supernova. (craffic.co.in)
  • The atmosphere of the Earth protects us and all life on the planet from cosmic rays, solar ultraviolet radiation and solar winds. (lu.se)
Organic6
  • Apart from its use in fertilisers and energy stores, nitrogen is a constituent of organic compounds as diverse as Kevlar used in high-strength fabric and cyanoacrylate used in superglue. (wikipedia.org)
  • The nitrogen cycle describes the movement of the element from the air, into the biosphere and organic compounds, then back into the atmosphere. (wikipedia.org)
  • Many drugs are mimics or prodrugs of natural nitrogen-containing signal molecules: for example, the organic nitrates nitroglycerin and nitroprusside control blood pressure by metabolizing into nitric oxide. (wikipedia.org)
  • 2022. Simulation of organics in the atmosphere: evaluation of EMACv2.54 with the Mainz Organic Mechanism (MOM) coupled to the ORACLE (v1.0) submodel. (ornl.gov)
  • As our knowledge of the distributions of carbon and nitrogen isotopes in organic matter and the factors controlling them has accumulated, the scope of isotopic measurements has greatly expanded. (springeropen.com)
  • Carbon-14, is based on organic materials that carbon isotope dating principle in radioactive isotope of about 5730 years ago. (turismolasnavas.es)
Molecules1
  • It's tempting to think of air as empty, but in fact, we live and breathe inside a 100 kilometer-thick layer of gas molecules called the atmosphere . (visionlearning.com)
Collide1
Urea2
  • Urea is the main source of synthetic nitrogen in Brazil, and our results from this research project are very promising because we demonstrated that farmers can decrease urea use while increasing nitrogen use efficiency by using these inhibitors," he said. (iaea.org)
  • We offer pre-isotope analysis lipid and urea extraction for diet and tracer studies. (uga.edu)
Lightest2
  • Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. (wikipedia.org)
  • Most elements of biological interest (including C, H, O, N, and S) have two or more stable isotopes, with the lightest of these present in much greater abundance than the others. (uga.edu)
Greenhouse1
  • They also release vast amounts of greenhouse gases into the atmosphere, first when vegetation is burned and later as the dead vegetation decays. (lu.se)
Organism3
  • The ratio within its body will stay the same as the atmosphere was when the organism died. (moravek.com)
  • The isotopic distributions of carbon and nitrogen in a single organism as well as in the whole biosphere are strongly regulated, so that their major components such as amino acids are coordinated appropriately rather than controlled separately. (springeropen.com)
  • The third fact is that when an organism dies, it no longer maintains the same ratio of carbon isotopes as the atmosphere. (actforlibraries.org)
Combines with oxygen to form1
  • It readily combines with oxygen to form 14CO2-radioactive carbon dioxide , which mixes throughout the atmosphere. (encyclopedia.com)
Reactive1
  • Changes to our atmosphere associated with reactive gases (gases that undergo chemical reactions) like ozone and ozone-forming chemicals like nitrous oxides, are relatively short-lived. (nasa.gov)
Fertilizers1
  • Going a step further, this irrigation system also can be used to target use of nitrogen fertilizers. (iaea.org)
Biosphere2
  • The following 210 publications cited the Large Scale Biosphere-Atmosphere Experiment (LBA-ECO) project. (ornl.gov)
  • The subsequent decrease is due to carbon exchange between atmosphere, ocean and biosphere. (uni-heidelberg.de)
Dioxide4
  • Thus, as humans change the atmosphere by emitting carbon dioxide, those changes will endure on the timescale of many human lives. (nasa.gov)
  • A chart showing the steadily increasing concentrations of carbon dioxide in the atmosphere (in parts per million) observed at NOAA's Mauna Loa Observatory in Hawaii over the course of 60 years. (nasa.gov)
  • The Martian atmosphere contains mostly carbon dioxide, unlike the nitrogen- and oxygen-rich air we breathe on Earth. (visionlearning.com)
  • The carbon atoms in your body were all once part of the carbon dioxide fraction of the atmosphere. (factscrush.com)
Elemental2
  • Elemental nitrogen is usually produced from air by pressure swing adsorption technology. (wikipedia.org)
  • About 2/3 of commercially produced elemental nitrogen is used as an inert (oxygen-free) gas for commercial uses such as food packaging, and much of the rest is used as liquid nitrogen in cryogenic applications. (wikipedia.org)
Molecule1
Biological3
  • So, nitrogen-15 technique was essential for us to determine which crops have high biological nitrogen efficiency. (iaea.org)
  • Radioactive isotopes are fairly effective for tracing because their radioactivity is easily detectable, which yields useful information for specific identification and the ongoing physical, chemical, or biological process at hand. (moravek.com)
  • Air pollution is contamination of the indoor or outdoor environment by any chemical, physical or biological agent that modifies the natural characteristics of the atmosphere. (who.int)
Gases1
  • In addition to these major components, the atmosphere also contains very small amounts of other gases that prove especially useful in understanding the origin and history of our atmosphere. (visionlearning.com)
Concentration1
  • We do this by calculating the amount of Carbon-14 in the sample and comparing it to the concentration of Carbon-14 in the atmosphere when the sample was made. (datingsidekick.com)
Billions of years1
  • Other radioactive isotopes, such as potassium-40, uranium-235, uranium-238, thorium-232, and rubidium-87, have half-lives that extend from millions to billions of years. (juniorsbook.com)