We present a chemical model of magma degassing based on nine volatile species part of S-O-H-C-Fe-bearing rhyolitic melts. It is based on equilibrium, closed-system degassing, and does not take in account the crystallization of mineral phases. For given initial conditions at depth, the model calculates the gas composition as pressure decreases, as well as physical variables controlling conduit f...

Variation of fragility (m) of specially homogenized Ge(x)Se(100-x) melts is established from complex specific heat measurements and shows that m(x) has a global minimum at an extremely low value (m = 14.8(0.5)) in the 21.5% < x < 23% range of Ge. Outside of that compositional range, m(x) then increases first rapidly and then slowly to about m = 25-30. By directly mapping melt stoichiometry as a...

Liquidus phase relationships have been determined for a high-MgO basalt (STV301: MgO 12.5 wt%, Ni 250 ppm, Cr 728 ppm) from Black Point, St Vincent (Lesser Antilles arc). Piston-cylinder experiments were conducted between 7.5 and 20 kbar under both hydrous and oxidizing conditions. AuPd capsules were used as containers. Compositions of supraliquidus glasses and mass-balance calculations show th...

We present results from constant pressure molecular-dynamics simulations for a bead-spring model of a crystallizable polymer melt. Our model has two main features, a chemically realistic intrachain rigidity and a purely repulsive interaction between nonbonded monomers. By means of intrachain and interchain structure factors we explore polymer conformation and melt structure above and below the ...

Microcellular injection molding using supercritical fluid (SCF) as blowing agent attracts more and more interests. There are still many difficulties in microcellular injection molding, such as decreasing equipment cost, controlling cellular morphology, and increasing feasibility. In this work, primary microcellular injection molding experiments were carried out on newly-developed equipment, whi...

A mathematical model that explores the basic transport phenomena in a Czochralski process, their interaction and influence on the growth of high quality oxide crystals is presented. Rare earth garnets YAG and Nd-doped YAG are considered as representative oxide materials for the purpose of modeling and numerical simulation. The model proposed is evolutionary in time, and axisymmetric in space. A...

See related article, pages 2633–2639. For nearly a decade, intra-arterial fibrinolytic therapy for acute ischemic stroke has stood poised on the threshold of a definitive evidential basis and widespread acceptance. The positive result of the phase 3 PROACT II trial in 1999 appeared to validate the pathophysiologically eminently reasonable strategy of endovascular recanalization in acute ischemi...

In this second installment of a series that aims to investigate the dynamic interaction between the composition and abundance of the solid mantle and its melt products, the classic interpretation of fractional melting is extended to account for the dynamic nature of the process. A multiphase numerical flow model is coupled with the program AlphaMELTS, which provides at the moment possibly the m...

Poly(vinylidene fluoride-co-tetrafluoroethylene) (PVDF-TFE) is confined between alternating layers of poly(ethylene terephthalate) (PET) utilizing a unique multilayer processing technology, in which PVDF-TFE and PET are melt-processed in a continuous fashion. Postprocessing techniques including biaxial orientation and melt recrystallization were used to tune the crystal orientation of the PVDF-...

Explosive eruptions involve mainly silicic magmas in which sulfur solubility and diffusivity are low. This inhibits sulfur exsolution during magma uprise as compared to more mafic magmas such as basalts. Silicic magmas can nevertheless liberate large quantities of sulfur as shown by the monitoring of SO2 in recent explosive silicic eruptions in arc settings, which invariably have displayed an e...