749 research outputs found
Solvation Effects in Near-Critical Binary Mixtures
A Ginzburg-Landau theory is presented to investigate solvation effects in
near-critical polar fluid binary mixtures. Concentration-dependence of the
dielectric constant gives rise to a shell region around a charged particle
within which solvation occurs preferentially. As the critical point is
approached, the concentration has a long-range Ornstein-Zernike tail
representing strong critical electrostriction. If salt is added, strong
coupling arises among the critical fluctuations and the ions. The structure
factors of the critical fluctuations and the charge density are calculated and
the phase transition behavior is discussed.Comment: 12 pages, 8 figures, to be published in J. Chem. Phy
Market Diffusion with Consumer-Based Bilateral Learning
This paper analyzes the market diffusion of a new product whose quality is uncertain. Consumers learn the product quality by observing the history of market outcomes. Firms cannot observe how consumers evaluate the product quality; instead, they learn by observing consumer behavior. New entry occurs gradually because of informational externalities. This dual uncertainty contributes to an S-shaped diffusion of the new product with declining prices.Experience Goods; Quality Uncertainty; Bilateral Learning; S-shaped Diffusion.
Selenium uptake onto natural pyrite
79Se is a major dose-determining redox-sensitive nuclide in safety analysis of radioactive waste disposal sites. In aqueous solutions, selenium forms soluble anionic species (SeIVO3 2− and SeVIO4 2−) that hardly sorb on negatively charged surfaces of common host-rock minerals. However, Se is known to have a strong affinity with sulphides and interacts with pyrite, a common minor mineral of argillaceous rocks being considered as host formations for radioactive waste repositories. In this study, we present micro- and bulk X-ray spectroscopy data (μ-XRF, μ-XANES, and EXAFS) showing that, under nearly anoxic conditions, dissolved SeO3 2− and SeO4 2− sorb directly onto the pyrite surface and are subsequently reduced to Se0 with increasing ageing time (up to 8months). These results suggest that the mobility of 79SeIV released from radioactive waste could greatly decrease through uptake on the pyrite surface followed by transformation into a sparingly soluble reduced for
A cooling rate constraint on microtextural development of plagioclase and scapolite: an example from the Lutzow-Holm Complex, East Antarctica
Exsolution lamellae in albite-rich plagioclase and antiphase domains in scapolite from the Lutzow-Holm Complex of East Antarctica were found under a transmission electron microscope.These micro-textures were found in the first cooling period of the three period cooling model proposed from the geochronological data. Based on these micro-textures,the cooling rate of the complex was estimated to be in a range from several to thousands K/my. These rates are concordant with those estimated from the ages of the complex
Free Entry, Market Diffusion, and Social Inefficiency with Endogenously Growing Demand
* Revised: [11-04, 2011
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