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Studies in the synthesis of n-butyl strontiumKuck, John F. R. January 1940 (has links)
1. Strontium does not easily react with n-butyl bromide in ether or benzene to produce an organostrontium compound. Strontium amalgam reacts to give a trace of the butyl mercury compound, perhaps through the formation of an organostrontium compound as intermediate.
2. The conversion, 2BuLi + SrCl₂ = 2LiCl + Bu₂Sr, seems to proceed predominantly to the left, perhaps because of relative solubilities of the lithium and strontium halides in the solvents used.
3. The conversion, Bu₂Hg + Sr = Hg + Bu₂Sr, appears to proceed to a slight extent to the right. So far, this reaction seems to offer the most promise in synthesizing an organostrontium compound. / M.S.
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Identifying Prehistoric Origin and Mobility : using Strontium analysis and laser ablation on teeth enamel from Viking Age boat-graves XI and XIII from Tuna in AlsikeGhattas Lama, Elias January 2015 (has links)
The Viking Age cemetery of Tuna in Alsike from the 9th - 11th century AD is located in the eastern part of middle Sweden and contains inhumation boat graves. Here analysis of Strontium isotopes, using laser ablation method on the tooth enamel of the canine and first molar of two individuals buried in boat-graves XI and XIII have been performed. Comparing Strontium isotope evidence with local strontium ratios and variations indicated that at least one individual, the one in boat-grave XIII, were non-local.
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Novel strontium fortified calcium salt for enhancing bone formation: an in vitro and in vivo large animal modelstudyLi, Zhaoyang, 李朝陽 January 2007 (has links)
published_or_final_version / abstract / Orthopaedics and Traumatology / Doctoral / Doctor of Philosophy
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Solute Inputs to Soil and Stream Waters in a Seasonally Snow-Covered Mountain Catchment Determined Using Ge/Si, ⁸⁷SR/⁸⁶SR and Major Ion Chemistry: Valles Caldera, New MexicoPorter, Courtney January 2012 (has links)
Weathering releases lithogenic elements to soil and stream waters that support life in catchment ecosystems. Seasonal and inter-annual variations in hydrologic conditions change subsurface flowpaths, modifying the influence of weathering on stream waters. This study, over two climatically variable years, determined seasonal and inter-annual changes in solute sources to streams using a multi-tracer approach including major cations, strontium isotopes, germanium (Ge)/silica ratios, carbon species, and trace metals. Stream water cations display constant concentrations although discharge response was highly variable, suggesting that there is a consistent subsurface water supply. However, Sr isotope ratios, and concentrations of Ge, Fe, Al, and dissolved organic carbon, which originate from shallow soil waters, increase with the hydrograph during a wet winter snowmelt. This indicates that during a year with a thick snowpack, stream waters contain components of both shallow soilwater and groundwater during snowmelt, whereas during all other times groundwater contributes predominantly to the stream.
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Laser spectroscopy of strontium-sulfide and alkaline earth monoborohydridesPianalto, Frederick Scott, 1961- January 1988 (has links)
Three gas phase alkaline earth molecules were analyzed using dye laser spectroscopy. The A¹Σ⁺ - X¹Σ⁺ transition of gas phase SrS was studied with high resolution techniques. The 0-0, 0-1, 1-1, 2-1, 3-0, 3-2, 4-1, 5-1, and 5-2 bands were rotationally analyzed and spectroscopic constants were determined. The A¹Σ⁺ state was extensively perturbed. Ground state (X¹Σ⁺) constants derived from the analysis of the nine vibrational levels include: ωₑ = 388.2643 cm⁻¹, Bₑ = 0.1208034(33) cm⁻¹, and rₑ = 2.439687(14) Å. Excited state (A¹Σ⁺) constants determined include: Tₑ = 13932.7068(10) cm⁻¹, ωₑ = 339.1454(20) cm⁻¹, Bₑ = 0.1139895(38) cm⁻¹, and rₑ = 2.511601(17) Å. The spectra of calcium and strontium borohydrides were observed using low resolution laser spectroscopy. The spectra were assigned to the òA₁ - Ẋ²A₁ and Ḃ²E - Ẋ²A₁ transitions of CaBH₄ and SrBH₄. The vibrational frequencies of the metal-ligand stretch determined for CaBH₄ were 457 cm⁻¹ (Ẋ²A₁), 473 cm⁻¹ (Ā²A₁), and 465 cm⁻¹ (Ḃ²E). The corresponding SrBH4 frequencies were 399 cm⁻¹, 420 cm⁻¹, and 421 cm⁻¹.
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Strontium isotopes as a tracer for the origin of Mississippi valley-type sulfide deposits from the southeast Missouri and tri-state district of MissouriLange, Steven L January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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Etude de la reaction 89Y (d,a) 87Sr.Brien, Marcel January 1971 (has links)
No description available.
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Determination of ⁹⁰Sr/⁹⁰Y contamination using beta-particle spectroscopy with active gamma-ray discriminationBaik, Seung-Hyuk 08 August 1991 (has links)
Graduation date: 1992
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Spectroscopy of selected calcium and strontium containing polyatomic moleculesDick, Michael James January 2007 (has links)
A spectroscopic study of several calcium and strontium containing molecules has been completed. In total, seven electronic transitions from six different calcium or strontium containing species were observed and analyzed at high resolution.
Using laser excitation spectroscopy in a laser ablation source, the high-resolution spectra of the A2Π- X2Σ+ transition of SrCCH, the B2A1- X2A1 transition of CaCH3, the A2E- X2A1 and B2A1- X2A1 transitions of SrCH3, along with the B2E- X2A1 transitions of SrBH4 and CaBH4 have been recorded and analyzed. For each molecule, a geometric structure in the ground and excited states was estimated and the fine structure constants for the excited state were investigated. A comparison of these geometries and parameters with those of other calcium and strontium containing species has yielded important information on bonding and electronic structure. For the A2Π state of SrCCH, the B2A1 state of CaCH3, and the A2E and B2A1 states of SrCH3, it was found that these states arise predominantly from pσ or pπ atomic orbitals located on Ca+ or Sr+ ions, consistent with the analogous states of CaF, SrF, CaOH and SrOH. For the B2E states of SrBH4 and CaBH4 a similar analysis showed an increased amount of d-atomic orbital character in these states.
The D state of CaOH was investigated at high resolution using optical-optical double resonance spectroscopy in a Broida oven source. An analysis of the resulting molecular constants showed that the Ca-O bond length and spin-rotation parameter of the state have the smallest values of those for all the observed 2Σ+ states of CaOH. This evidence suggested that the D2Σ+ state arises from a Ca+ atomic orbital of mainly 5sσ character. This atomic orbital assignment was shown to be consistent with both previous work on CaF and recent theoretical calculations on CaOH.
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Spectroscopy of selected calcium and strontium containing polyatomic moleculesDick, Michael James January 2007 (has links)
A spectroscopic study of several calcium and strontium containing molecules has been completed. In total, seven electronic transitions from six different calcium or strontium containing species were observed and analyzed at high resolution.
Using laser excitation spectroscopy in a laser ablation source, the high-resolution spectra of the A2Π- X2Σ+ transition of SrCCH, the B2A1- X2A1 transition of CaCH3, the A2E- X2A1 and B2A1- X2A1 transitions of SrCH3, along with the B2E- X2A1 transitions of SrBH4 and CaBH4 have been recorded and analyzed. For each molecule, a geometric structure in the ground and excited states was estimated and the fine structure constants for the excited state were investigated. A comparison of these geometries and parameters with those of other calcium and strontium containing species has yielded important information on bonding and electronic structure. For the A2Π state of SrCCH, the B2A1 state of CaCH3, and the A2E and B2A1 states of SrCH3, it was found that these states arise predominantly from pσ or pπ atomic orbitals located on Ca+ or Sr+ ions, consistent with the analogous states of CaF, SrF, CaOH and SrOH. For the B2E states of SrBH4 and CaBH4 a similar analysis showed an increased amount of d-atomic orbital character in these states.
The D state of CaOH was investigated at high resolution using optical-optical double resonance spectroscopy in a Broida oven source. An analysis of the resulting molecular constants showed that the Ca-O bond length and spin-rotation parameter of the state have the smallest values of those for all the observed 2Σ+ states of CaOH. This evidence suggested that the D2Σ+ state arises from a Ca+ atomic orbital of mainly 5sσ character. This atomic orbital assignment was shown to be consistent with both previous work on CaF and recent theoretical calculations on CaOH.
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