New data are presented on Rb-Sr isotope analyses of phosphates from nine ordinary chondrites, including accurate identification of initial Sr-87/Sr-86. The initial Sr-87/Sr-86 ratios found in this study were generally significantly higher than the more ...

New data are presented on Rb-Sr isotope analyses of phosphates from nine ordinary chondrites, including accurate identification of initial Sr-87/Sr-86. The initial Sr-87/Sr-86 ratios found in this study were generally significantly higher than the more ...

We have measured the Sr concentration and isotopic composition of most of the world's major rivers. These data greatly extend the range of geologic, tectonic and climatic drainage basin environments that have been studied and, overall, constitute a doubling of the fluvial Sr isotope data base. This has produced a ...

Procedures have been developed for the accurate trace analysis of Rb and Sr by mass spectrometric isotope dilution. A new Sr isotopic assay technique capable of measuring the three abundant Sr isotopes to <0.05% (ts) was combined with recently ...

The 87Rb 86Sr system is a widely used long-lived isotope geochronometer. 87Rb, the naturally occurring radioactive isotope of Rb, undergoes beta-decay to stable 87Sr with a half-life of approximately 50 Ga. Decay of 87Rb to 87Sr results in variable ...

Although variation in 87Sr/86Sr has been widely pursued as a tracer of provenance in environmental studies, forensics, archeology and food traceability, accurate models of the large-scale variation in environmental 87Sr/86Sr are not available. In this paper, we build upon earlier efforts to ...

Precambrian Sr isotope stratigraphy was investigated by determining variations in Sr-87/Sr-86 ratios

Sr-isotopic results are obtained for three basalt samples from Station 4, and it is shown that these

Strontium-90 is one of the most important fission products generated in nuclear industry. In the research field concerning nuclear waste disposal in deep geological environment, it is necessary to quantify accurately and precisely its concentration (or the 90Sr / 238U atomic ratio) in irradiated fuels. To obtain accurate analysis of ...

The ability to conduct multi-isotopic analyses (e.g., Sr-Nd-Hf-Pb) on the same sample is critical for studies that evaluate the mantle source components of oceanic basalts. The isotopic compositions of relatively immobile elements, such as Nd (and other REE) and Hf, are considered to be relatively resistant to alteration, however, ...

Otolith Sr/Ca has become a popular tool for hind casting habitat utilization and migration histories of euryhaline fish. It can readily identify habitat shifts of diadromous fish in most systems. Inferring movements of fish within estuarine habitat, however, requires a model of that accounts of the local water chemistry and the response of individual species to that water ...

The achievement in 1995 of Bose-Einstein condensates (BEC) in dilute gases of alkali- metal atoms was one of the most important experimental results in recent times. Fifteen years later, the study of quantum fluids is a vibrant field exploring topics such as the effects of dimensionality and disorder on quantum fluids and the modeling of condensed-matter systems with BECs in optical lattices. This ...

We describe repumping and spectroscopy of laser-cooled strontium (Sr) atoms using the (5s5p)3P2-(5s4d)3D2 transition. Atom number in a magneto-optical trap is enhanced by driving this transition because Sr atoms that have decayed into the (5s5p)3P2 dark state are repumped back into the (5s2)1S0 ground state. Spectroscopy of 84Sr, ...

The strontium (88Sr/86Sr) stable isotope composition of seawater reflects input from continental weathering and hydrothermal exchange at mid-ocean ridges, and output in carbonate sediments. Variations in the stable isotope composition of seawater over time reflect either changes in the balance of carbonate to ...

samples (NWA 1068, LAR 06319 and RBT 04262) have higher abundances of these ... Rb-Sr Isotopic System: The 87Rb/86Sr and. 87Sr/86Sr data for one unwashed ...

This paper reviews the problems encountered in eleven studies of Sr isotope analysis using laser ablation multicollector inductively coupled plasma mass spectrometry (LA-MC-ICPMS) in the period 1995-2006. This technique has been shown to have great potential, but the accuracy and precision are limited by: (1) large instrumental mass discrimination, (2) ...

This paper reviews the problems encountered in eleven studies of Sr isotope analysis using laser ablation multicollector inductively coupled plasma mass spectrometry (LA-MC-ICPMS) in the period 1995�2006. This technique has been shown to have great potential, but the accuracy and precision are limited by: (1) large instrumental mass discrimination, (2) ...

New isotope dilution results are presented for Rb and Sr concentrations in U.S.G.S. stndard rocks and NHS-70a K-feldspar. The results (based on at least five analyses of each rock), are generally accurate to plus or minus 0.5% and resolve discrepancies in previously published data. X-ray fluorescence analyses of the same ...

In December of 2007, the ANDRILL (ANtarctic Geological DRILLing program) Southern McMurdo Sound project recovered core AND-2A. The goal of the project was to reconstruct ice sheet and climate variation in Antarctica during the Neogene, and in doing so, obtain a clearer perspective on polar climate evolution. Initial attempts to apply Sr isotope ...

The stable strontium (88Sr/86Sr) isotope composition of seawater recorded in sedimentary foraminifera potentially provides key information on variations in the composition of material delivered by continental weathering to the oceans and on changes in carbonate productivity over time. However, recent studies suggest a significant ...

We analyzed Nd and Sr isotopic compositions of Neogene fossil fish teeth from two sites in the Pacific in order to determine the effect of cleaning protocols and burial diagenesis on the preservation of seawater isotopic values. Sr is incorporated into the teeth at the time of growth; thus Sr ...

A simple and rapid procedure was developed for purification of cyclotron produced 86Y via the 86Sr(p,n) 86Y reaction. A commercially available Sr(II) selective resin was used to separate 86Y from the cyclotron irradiated Sr(II) target with a recovery of the enriched Sr(II) target while yielding a 75-80% recovery of ...

Rb-Sr isotope patterns in tekites from Southeast Australian strewn field, studying Rb volatilization

determined the Rb, Sr isotopic composition of the .... Sr. 104. (a) 70. (e) 97.6 . (d). 90 .... Strontium isotope geochemistry of Apollo 15 basalts. In ...

Sm-Nd and Rb-Sr isotopic data on suspended material from rivers draining a variety of rock types and

... (1987) agree with the four component model of ... coefficients, and the X 's are the original isotope measurements (X1 = 87 Sr/ 86 Sr, ...

dissolved, there would be insufficient Sr in a body of reasonable size to effect the change. Thus the in- crease in 87Sr/86Sr seems to require a greatly ...

Mass spectrometric analysis of sedimentary rocks for Sr-Rb and Sr isotopic composition from Bosumtwi

We study the collision and evaporation dynamics of both bosonic and fermionic isotopes of strontium (Sr) in a 1064 nm optical dipole trap. Because of the small s-wave scattering length for the bosonic ^88Sr isotope, the elastic-scattering cross section depends strongly on collisional energies. Extending this model ...

A major limitation on the supply of the short-lived medical isotope 90Y (t1/2 = 64 h) is the available quantity of highly purified 90Sr generator material. A radiochemical production campaign was therefore undertaken to purify 1,500 Ci of 90Sr that had been isolated from fission waste materials. A series of alkaline precipitation steps ...

In order to evaluate alternative analytical methodologies to study the geographical origin of ciders, both multi-elemental analysis and Sr isotope abundance ratios in combination with multivariate statistical analysis were estimated in 67 samples from England, Switzerland, France and two Spanish regions (Asturias and the Basque Country). A methodology for ...

Stratigraphic sections of the Southern Urals containing abundant and well-preserved fauna for precise biostratigraphic correlation and common instratified volcanic ash beds dated by U-Pb zircon geochronology offer a unique opportunity to constrain a temporally accurate Late Pennsylvanian-Early Permian seawater Sr curve. The ...

Because of its small cross section, the ⁸⁸Sr(n,g) reaction is an important bottleneck during s-process nucleosynthesis. Hence, an accurate determination of this rate is needed to better constrain the neutron exposure in s-process models and to more fully exploit the recently discovered isotopic anomalies in ...

Comparison of the 87^Sr/86^Sr isotopic ratio of fossil fish teeth (ichthyoliths) with the global seawater Sr curve should provide a highly accurate method for dating pelagic clay cores. This is potentially useful for deep sea red clay cores that are rich in ichthyolith material but barren of ...

A combined procedure for separating Lu, Hf, Rb, Sr, Sm and Nd from a single sample digestion is presented in this paper. The procedure consists of the following four steps: (1) sample dissolution in a mixture of concentrated HF-HNO3-HClO4; (2) Lu and Hf separation from the Rb, Sr, LMREE and other matrix elements by HF-free extraction chromatography; (3) ...