Isotope and Nuclear Chemistry Division Annual Report FY1987
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Nitrogen Isotope Variations in the Solar System Evelyn Füri and Bernard Marty
REVIEW ARTICLE PUBLISHED ONLINE: 15 JUNE 2015 | DOI: 10.1038/NGEO2451 Nitrogen isotope variations in the Solar System Evelyn Füri and Bernard Marty The relative proportion of the two isotopes of nitrogen, 14N and 15N, varies dramatically across the Solar System, despite little variation on Earth. NASA’s Genesis mission directly sampled the solar wind and confirmed that the Sun — and, by inference, the protosolar nebula from which the Solar System formed — is highly depleted in the heavier isotope compared with the reference nitrogen isotopic composition, that of Earth’s atmosphere. In contrast, the inner planets, asteroids, and comets are enriched in 15N by tens to hundreds of per cent; organic matter in primitive meteorites records the highest 15N/14N isotopic ratios. The measurements indicate that the protosolar nebula, inner Solar System, and cometary ices represent three distinct isotopic reservoirs, and that the 15N enrichment generally increases with distance from the Sun. The 15N enrichments were probably not inherited from presolar material, but instead resulted from nitrogen isotope fractionation processes that occurred early in Solar System history. Improvements in analytical techniques and spacecraft observations have made it possible to measure nitrogen isotopic variability in the Solar System at a level of accuracy that offers a window into the processing of early Solar System material, large-scale disk dynamics and planetary formation processes. he Solar System formed when a fraction of a dense molecu- a matter of debate, the D/H isotopic tracer offers the possibility of lar cloud collapsed and a central star, the proto-Sun, started investigating the relationships between the different Solar System Tburning its nuclear fuel1. -
Element Builder
Name: ______________________________________ Date: ________________________ Student Exploration: Element Builder Prior Knowledge Questions (Do these BEFORE using the Gizmo.) 1. What are some of the different substances that make up a pizza? _____________________ _________________________________________________________________________ 2. What substances make up water? _____________________________________________ 3. What substances make up an iron pot? _________________________________________ Elements are pure substances that are made up of one kind of atom. Pizza is not an element because it is a mixture of many substances. Water is a pure substance, but it contains two kinds of atom: oxygen and hydrogen. Iron is an element because it is composed of one kind of atom. Gizmo Warm-up Atoms are tiny particles of matter that are made up of three particles: protons, neutrons, and electrons. The Element Builder Gizmo™ shows an atom with a single proton. The proton is located in the center of the atom, called the nucleus. 1. Use the arrow buttons ( ) to add protons, neutrons, and electrons to the atom. Press Play ( ). A. Which particles are located in the nucleus? _________________________________ B. Which particles orbit around the nucleus? __________________________________ 2. Turn on Show element name. What is the element? ________________________ 3. Manipulate the gizmo to figure out what actions cause the element name to change. _____________________________________________________________________ _____________________________________________________________________ Get the Gizmo ready: Activity A: Use the arrows to create an atom with two protons, Subatomic two neutrons, and two electrons. particles Turn on Show element name. Question: What are the properties of protons, neutrons, and electrons? 1. Observe: Turn on Show element symbol and Element notation. Three numbers surround the element symbol: the mass number, electrical charge (no number is displayed if the atom is neutral), and the atomic number. -
Groundwater Quality Data for the Northern Sacramento Valley, 2007: Results from the California GAMA Program
Prepared in cooperation with the California State Water Resources Control Board A product of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program Groundwater Quality Data for the Northern Sacramento Valley, 2007: Results from the California GAMA Program SHASTA CO Redding 5 Red Bluff TEHAMA CO Data Series 452 U.S. Department of the Interior U.S. Geological Survey Cover Photographs: Top: View looking down the fence line, 2008. (Photograph taken by Michael Wright, U.S. Geological Survey.) Bottom: A well/pump in a field, 2008. (Photograph taken by George Bennett, U.S. Geological Survey.) Groundwater Quality Data for the Northern Sacramento Valley, 2007: Results from the California GAMA Program By Peter A. Bennett, George L. Bennett V, and Kenneth Belitz In cooperation with the California State Water Resources Control Board Data Series 452 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2009 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. -
Making a Manhattan Project National Historical Park
Atomic Heritage Foundation Preserving and Interpreting Manhattan Project History & Legacy Making A manhattan Project National Historical Park AnnualAnnual ReportReport 2010 Why should We Preserve the Manhattan Project? “The factories and bombs that Manhattan Project scientists, engineers, and workers built were physical objects that depended for their operation on physics, chemistry, metallurgy, and other natural sciences, but their social reality - their meaning, if you will - was human, social, political. We preserve what we value of the physical past because it specifically embodies our social past. When we lose parts of our physical past, we lose parts of our common social past as well.” “The new knowledge of nuclear energy has undoubtedly limited national sovereignty and scaled down the destructiveness of war. If that’s not a good enough reason to work for and contribute to the Manhattan Project’s historic preservation, what would be?” -Richard Rhodes, “Why We Should Preserve the Manhattan Project,” Bulletin of the Atomic Scientists, May/June 2006 Remnant of the K-25 plant during the demolition of the east wing. See story on page 6. Front cover (clockwise from upper right): The B Reactor at Hanford, J. Robert Oppenheimer’s house in Los Alamos, and the K-25 Plant at Oak Ridge. These properties are potential components of a Manhattan Project National Historical Park. Table of Contents Board Members & Advisory Committee............3 George Cowan and Jay Wechsler Letter from the President......................................4 Manhattan Project Sites: Past & Present.......5 Saving K-25: A Work in Progress..........................6 AHF Releases New Guide............................................7 LAHS Hedy Dunn and Heather McClenahan. -
12 Natural Isotopes of Elements Other Than H, C, O
12 NATURAL ISOTOPES OF ELEMENTS OTHER THAN H, C, O In this chapter we are dealing with the less common applications of natural isotopes. Our discussions will be restricted to their origin and isotopic abundances and the main characteristics. Only brief indications are given about possible applications. More details are presented in the other volumes of this series. A few isotopes are mentioned only briefly, as they are of little relevance to water studies. Based on their half-life, the isotopes concerned can be subdivided: 1) stable isotopes of some elements (He, Li, B, N, S, Cl), of which the abundance variations point to certain geochemical and hydrogeological processes, and which can be applied as tracers in the hydrological systems, 2) radioactive isotopes with half-lives exceeding the age of the universe (232Th, 235U, 238U), 3) radioactive isotopes with shorter half-lives, mainly daughter nuclides of the previous catagory of isotopes, 4) radioactive isotopes with shorter half-lives that are of cosmogenic origin, i.e. that are being produced in the atmosphere by interactions of cosmic radiation particles with atmospheric molecules (7Be, 10Be, 26Al, 32Si, 36Cl, 36Ar, 39Ar, 81Kr, 85Kr, 129I) (Lal and Peters, 1967). The isotopes can also be distinguished by their chemical characteristics: 1) the isotopes of noble gases (He, Ar, Kr) play an important role, because of their solubility in water and because of their chemically inert and thus conservative character. Table 12.1 gives the solubility values in water (data from Benson and Krause, 1976); the table also contains the atmospheric concentrations (Andrews, 1992: error in his Eq.4, where Ti/(T1) should read (Ti/T)1); 2) another category consists of the isotopes of elements that are only slightly soluble and have very low concentrations in water under moderate conditions (Be, Al). -
Investigation of Nitrogen Cycling Using Stable Nitrogen and Oxygen Isotopes in Narragansett Bay, Ri
University of Rhode Island DigitalCommons@URI Open Access Dissertations 2014 INVESTIGATION OF NITROGEN CYCLING USING STABLE NITROGEN AND OXYGEN ISOTOPES IN NARRAGANSETT BAY, RI Courtney Elizabeth Schmidt University of Rhode Island, [email protected] Follow this and additional works at: https://digitalcommons.uri.edu/oa_diss Recommended Citation Schmidt, Courtney Elizabeth, "INVESTIGATION OF NITROGEN CYCLING USING STABLE NITROGEN AND OXYGEN ISOTOPES IN NARRAGANSETT BAY, RI" (2014). Open Access Dissertations. Paper 209. https://digitalcommons.uri.edu/oa_diss/209 This Dissertation is brought to you for free and open access by DigitalCommons@URI. It has been accepted for inclusion in Open Access Dissertations by an authorized administrator of DigitalCommons@URI. For more information, please contact [email protected]. INVESTIGATION OF NITROGEN CYCLING USING STABLE NITROGEN AND OXYGEN ISOTOPES IN NARRAGANSETT BAY, RI BY COURTNEY ELIZABETH SCHMIDT A DISSERTATION SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN OCEANOGRAPHY UNIVERSITY OF RHODE ISLAND 2014 DOCTOR OF PHILOSOPHY DISSERTATION OF COURTNEY ELIZABETH SCHMIDT APPROVED: Thesis Committee: Major Professor Rebecca Robinson Candace Oviatt Arthur Gold Nassar H. Zawia DEAN OF THE GRADUATE SCHOOL UNIVERSITY OF RHODE ISLAND 2014 ABSTRACT Estuaries regulate nitrogen (N) fluxes transported from land to the open ocean through uptake and denitrification. In Narragansett Bay, anthropogenic N loading has increased over the last century with evidence for eutrophication in some regions of Narragansett Bay. Increased concerns over eutrophication prompted upgrades at wastewater treatment facilities (WWTFs) to decrease the amount of nitrogen discharged. The upgrade to tertiary treatment – where bioavailable nitrogen is reduced and removed through denitrification – has occurred at multiple facilities throughout Narragansett Bay’s watershed. -
Using Stable Isotopes of Nitrogen and Carbon to Study Seabird Ecology: Applications in the Mediterranean Seabird Community*
SCI. MAR., 67 (Suppl. 2): 23-32 SCIENTIA MARINA 2003 MEDITERRANEAN SEABIRDS AND THEIR CONSERVATION. E. MÍNGUEZ, D. ORO, E. DE JUANA and A. MARTÍNEZ-ABRAÍN (eds.) Using stable isotopes of nitrogen and carbon to study seabird ecology: applications in the Mediterranean seabird community* MANUELA G. FORERO1 and KEITH A. HOBSON2 1 Instituto Mediterráneo de Estudios Avanzados (CSIC-UIB), C/Miquel Marqués, 21, 07190 Esporles, Mallorca, Spain. E-mail: [email protected] 2 Canadian Wildlife Service, 115 Perimeter Road, Saskatoon, SK, Canada, S7N0X4 SUMMARY: The application of the stable isotope technique to ecological studies is becoming increasingly widespread. In the case of seabirds, stable isotopes of nitrogen and carbon have been mainly used as dietary tracers. This approach relies on the fact that foodweb isotopic signatures are reflected in the tissues of the consumer. In addition to the study of trophic ecology, stable isotopes have been used to track the movement of seabirds across isotopic gradients, as individuals moving between isotopically distinct foodwebs can carry with them information on the location of previous feeding areas. Studies applying the stable isotope methodology to the study of seabird ecology show a clear evolution from broad and descriptive approaches to detailed and individual-based analyses. The purpose of this article is to show the different fields of applica- tion of stable isotopes to the study of the seabird ecology. Finally, we illustrate the utility of this technique by considering the particularities of the Mediterranean seabird community, suggesting different ecological questions and conservation prob- lems that could be addressed by using the stable isotope approach in this community. -
Reviewing Martian Atmospheric Noble Gas Measurements: from Martian Meteorites to Mars Missions
geosciences Review Reviewing Martian Atmospheric Noble Gas Measurements: From Martian Meteorites to Mars Missions Thomas Smith 1,* , P. M. Ranjith 1, Huaiyu He 1,2,3,* and Rixiang Zhu 1,2,3 1 State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, 19 Beitucheng Western Road, Box 9825, Beijing 100029, China; [email protected] (P.M.R.); [email protected] (R.Z.) 2 Institutions of Earth Science, Chinese Academy of Sciences, Beijing 100029, China 3 College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China * Correspondence: [email protected] (T.S.); [email protected] (H.H.) Received: 10 September 2020; Accepted: 4 November 2020; Published: 6 November 2020 Abstract: Martian meteorites are the only samples from Mars available for extensive studies in laboratories on Earth. Among the various unresolved science questions, the question of the Martian atmospheric composition, distribution, and evolution over geological time still is of high concern for the scientific community. Recent successful space missions to Mars have particularly strengthened our understanding of the loss of the primary Martian atmosphere. Noble gases are commonly used in geochemistry and cosmochemistry as tools to better unravel the properties or exchange mechanisms associated with different isotopic reservoirs in the Earth or in different planetary bodies. The relatively low abundance and chemical inertness of noble gases enable their distributions and, consequently, transfer mechanisms to be determined. In this review, we first summarize the various in situ and laboratory techniques on Mars and in Martian meteorites, respectively, for measuring noble gas abundances and isotopic ratios. -
INTERSCALAR VEHICLES for an AFRICAN ANTHROPOCENE: on Waste, Temporality, and Violence
INTERSCALAR VEHICLES FOR AN AFRICAN ANTHROPOCENE: On Waste, Temporality, and Violence GABRIELLE HECHT Stanford University http://orcid.org/0000-0003-1445-0785 Brightly painted concrete houses, equipped with running water and elec- tricity, arranged in dozens of identical rows: this photograph (Figure 1) depicts the newly built company town of Mounana in eastern Gabon. The road is clean, the children happy. In the late 1970s, this image represented Gabonese “expec- tations of modernity” (Ferguson 1999) through national and corporate projects. By the end of this essay, I hope you will also see it as an image of the African Anthropocene. The idea of an African Anthropocene may seem like a paradox. After all, the biggest appeal of the idea of the Anthropocene has been its “planetarity” (DeLoughrey 2014). For some geologists, the Anthropocene signals the start of a new epoch, one in which humans permanently mark the stratigraphic record with their “technofossils” (Zalasiewicz et al. 2014). Other earth scientists adopt the notion to signal humanity’s catastrophic effects on the planet’s physical and biochemical systems. During the past decade, the term has become a “charismatic mega-category” (Reddy 2014) across the humanities, arts, and natural and social sciences (Steffen et al. 2011; Ellsworth and Kruse 2012). Inevitably, debates rage about origins and nomenclature. Did the Anthropocene begin with the dawn of human agriculture? Or with the Columbian exchange of the sixteenth and sev- enteenth centuries? How about the start of European industrialization in the eigh- CULTURAL ANTHROPOLOGY, Vol. 33, Issue 1, pp. 109–141, ISSN 0886-7356, online ISSN 1548-1360. -
Stable Isotopes of Carbon and Nitrogen in the Study of Avian and Mammalian Trophic Ecology
Color profile: Disabled Composite Default screen 1 REVIEW/SYNTHÈSE Stable isotopes of carbon and nitrogen in the study of avian and mammalian trophic ecology Jeffrey F. Kelly Abstract: Differential fractionation of stable isotopes of carbon during photosynthesis causes C4 plants and C3 plants to have distinct carbon-isotope signatures. In addition, marine C3 plants have stable-isotope ratios of carbon that are 13 12 intermediate between C4 and terrestrial C3 plants. The direct incorporation of the carbon-isotope ratio ( C/ C) of plants into consumers’ tissues makes this ratio useful in studies of animal ecology. The heavy isotope of nitrogen (15N) is preferentially incorporated into the tissues of the consumer from the diet, which results in a systematic enrichment in nitrogen-isotope ratio (15N/14N) with each trophic level. Consequently, stable isotopes of nitrogen have been used pri- marily to assess position in food chains. The literature pertaining to the use of stable isotopes of carbon and nitrogen in animal trophic ecology was reviewed. Data from 102 studies that reported stable-isotope ratios of carbon and (or) nitrogen of wild birds and (or) mammals were compiled and analyzed relative to diet, latitude, body size, and habitat moisture. These analyses supported the predicted relationships among trophic groups. Carbon-isotope ratios differed among species that relied on C3,C4, and marine food chains. Likewise, nitrogen-isotope ratios were enriched in terres- trial carnivorous mammals relative to terrestrial herbivorous mammals. -
Jerry Sabloff on 30 Years of Complexity
January / February 2014 UPDATE IN THIS ISSUE > Drinking & reciprocity 2 > Wolpert’s reality check 2 > SFI In the News 2 > SFI@30: From the editor 2 > Behavior & institutions 3 > Ruben Andrist: Quantum fragility 3 > Infectious notions 3 > SFI@30: Conception to birth 4 > Science symphony 5 > Eggs, bacon, & science 5 > 50 years of the quark 5 > New MOOC: Dynamics & chaos 6 > Award for Project GUTS 6 > Four new SFI trustees 7 > Books by SFI authors 7 > Marking SFI’s 30th year 8 > SFI@30: Co-founder David Pines 8 Q&A: Jerry Sabloff on 30 years of complexity At the turn of the new year, Institute are important new insights into the nature of standing of complex adaptive systems. So President Jerry Sabloff offers his thoughts complex adaptive systems and the transdisci- they instituted, almost into SFI’s DNA, a about SFI’s outlook for 2014 and beyond. plinary methodologies that SFI has used to transdisciplinary approach – anthropologists explore the emergence and continuing working with computer scientists and In 2014, SFI celebrates its 30th anniversary. Update: Today, with this interview, SFI development of complexity at all scales, from mathematicians and biologists and so on. Watch SFI’s website and publications begins to mark its 30th year. What are SFI’s atoms and cells to human societies. One of This methodology has proven to be incred- for a yearlong celebration of the Institute’s storied history, and for opportunities top achievements, in your mind, since its the great insights of SFI’s founders – the late ibly successful, and it is now widely adopted to be an active member of SFI’s community. -
Isotopes of Nitrogen on Mars: Atmospheric Measurements by Curiosity’S Mass Spectrometer Michael H
GEOPHYSICAL RESEARCH LETTERS, VOL. ???, XXXX, DOI:10.1029/, Isotopes of nitrogen on Mars: Atmospheric measurements by Curiosity's mass spectrometer Michael H. Wong,1,2 Sushil K. Atreya,1 Paul N. Mahaffy,3 Heather B. Franz,3 Charles Malespin,3 Melissa M. Trainer,3 Jennifer C. Stern,3 Pamela G. Conrad,3 Heidi L.K. Manning,4 Robert O. Pepin,5 Richard H. Becker,5 Christopher P. McKay,6 Tobias C. Owen,7 Rafael Navarro-Gonz´alez,8 John H. Jones,9 Bruce M. Jakosky,10 and Andrew Steele11 The Sample Analysis at Mars (SAM) instrument suite on atmosphere and surface of Mars is not currently understood, the Mars Science Laboratory (MSL) measured a Mars at- but such exchange would be very important to the study of mospheric 14N/15N ratio of 173 ± 11 on sol 341 of the mis- martian habitability that is the focus of the MSL mission [Grotzinger et al., 2012]. sion, agreeing with Viking's measurement of 168 ± 17 [Nier The atmospheric nitrogen isotopic ratio is difficult to and McElroy, 1977]. The MSL/SAM value was based on measure. Very weak absorption lines are produced by the Quadrupole Mass Spectrometer (QMS) measurements of an dipole forbidden vibrational-rotational transitions of ground enriched atmospheric sample, with CO2 and H2O removed. state N2, so the spectroscopic techniques used to measure Doubly-ionized nitrogen data at m/z 14 and 14.5 had the isotope ratios in other molecules cannot be applied to molec- highest signal/background ratio, with results confirmed by ular nitrogen. Of the 10 science instruments of the MSL m/z 28 and 29 data.