Glasses Tech

March 8, 2010

Seeing One’s Partner Through Intimacy-Colored Glasses: An Examination of the Processes Underlying the Intimacy Goals-Relationship Satisfaction Link

Filed under: Glasses 2001 — admin @ 3:50 am

Eyeglasses

This research extends previous work demonstrating that individuals with intimacy goals experience greater relationship satisfaction by examining three distinct processes that may underlie this association (e.g., engaging in intimacy-conducive interactions with their partners, having intimacy-focused partners, perceiving partners as intimacy focused). The study included 100 female college students who completed measures of intimacy goals, patterns of relationship interaction, perceptions of their partner’s intimacy goals, and relationship satisfaction. (more…)

U-series Isotope Data on Lau Basin Glasses: the Role of Subduction-related Fluids during Melt Generation in Back-arc Basins

Filed under: Glasses 2001 — admin @ 3:49 am

New thermal ionization mass spectrometry U-series disequilibrium data are presented for 24 basaltic to dacitic glasses from active spreading centres in the back-arc Lau Basin (SW Pacific), together with additional inductively coupled plasma mass spectrometry trace element analyses and Sr–Nd–Pb isotope data. Valu Fa Ridge samples, adjacent to the arc front, have high U/Th and (230Th/238U) <1, implying a recent (< <350 ka) addition of a U-rich slab-derived fluid. The Valu Fa data can be combined with existing 230Th–238U data for the Central Tonga arc to infer a fluid addition event at 50 ka. The similar sources and time scales for fluid transfer beneath the Valu Fa Ridge and beneath the arc itself suggest that the Valu Fa Ridge is propagating into the arc-front region. (more…)

Volatiles in Basaltic Glasses from Loihi Seamount, Hawaii: Evidence for a Relatively Dry Plume Component

Filed under: Glasses 2001 — admin @ 3:47 am

New H2O, CO2 and S concentration data for basaltic glasses from Loihi seamount, Hawaii, allow us to model degassing, assimilation, and the distribution of major volatiles within and around the Hawaiian plume. Degassing and assimilation have affected CO2 and Cl but not H2O concentrations in most Loihi glasses. Water concentrations relative to similarly incompatible elements in Hawaiian submarine magmas are depleted (Loihi), equivalent (Kilauea, North Arch, Kauai–Oahu), or enriched (South Arch). (more…)

Ab initio studies of possible fluorine-bearing four- and fivefold coordinated Al species in aluminosilicate glasses

Filed under: Glasses 2001 — admin @ 3:45 am

Ab initio NMR gauge-including atomic orbital (GIAO) calculations were used to constrain assignments of resonances in 27Al NMR spectra of F-bearing alkali aluminosilicate glasses. The effect of bond angles within the range 126–150° on the chemical shift was investigated using cluster models of next-nearest atoms that are charge balanced by hydrogen atoms. GIAO calculations used geometries obtained through optimization at fixed Al-O-Si bond angles. (more…)

THE VALENCE AND SPECIATION OF SULFUR IN GLASSES BY X-RAY ABSORPTION SPECTROSCOPY

Filed under: Glasses 2001 — admin @ 3:43 am

The geochemical behavior of sulfur in magmas depends strongly on the oxidation state of sulfur, but this is not easily determined by standard analytical methods. We have measured XANES absorption spectra at the sulfur K-edge and have found that such measurements are useful to characterize the oxidation state and speciation of sulfur in silicate glasses of geological relevance. Measured spectra of a set of reference minerals show the effects of different oxidation states and coordination numbers of sulfur; there is a large shift in energy (~10–12 eV) of the sulfur K-edge between S2– and S6+. This large and easily detectable difference makes possible the measurement of the valence of sulfur in unknown samples by measuring the shift in energy of the absorption edge. This approach is applicable to both crystalline and glassy materials, and useful results have been obtained on samples with as little as 450 ppm S. We have used XANES measurements to characterize oxidation state and speciation of sulfur in a set of natural and synthetic sulfur-bearing glasses. (more…)

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