The calculation of water-rock ratios using trace element (Li, B) stable isotopes

The amount of aqueous fluids circulating into the oceanic crust can be estimated using mass balance equations based on stable isotope exchange between rock and water. Unlike oxygen and strontium, isotopic exchange of trace elements (such as B or Li) between fluids and rocks, operates along with a chemical evolution of the rocks (e.g. a large enrichment of B or Li) that must be integrated into any model of water-rock interaction. We propose a general dimensionless mass balance equation for single-pass open systems that describes the equilibrium elemental distribution and the isotopic composition of reacting rocks as a function of the amount of circulating water. Water-rock ratios calculated from B compositions of hydrothermally-altered basalts range from 8 to 100. They are lower than those previously published (most W/R > 300) but comparable to those inferred from Sr isotope ratios measured in the same samples (3 < W/R < 30). Similar low water-rock ratios from 2 to 20 are calculated from Li isotope compositions of altered basalts and serpentinized peridotites.

Hellmann Potential in Spinless Salpeter Equation with Potential Barrier within the Framework of Nikiforov-Uvarov method

<p>In this paper, we have solved the spinless Salpeter equation (SSE) with Hellmann potential under the framework of NIkiforov-Uvarov (NU) method. The energy eigenvalues and corresponding wave functions for this system express in terms of the Jacobi polynomial are also obtained. With the help of approximation scheme the potential barrier has been evaluated. The results obtained in this work would have many applications in nuclear physics, chemical physics, atomic and molecular physics, molecular chemistry and other related areas as the results under limiting cases could be used to study the binding energy and interaction of some diatomic molecules. As a guide to interested readers, we have provided numerical data which discuss the energy spectra for this system.</p><p> </p>

Dynamic Quantum Vacuum and Relativity

<p>A model of a three-dimensional dynamic quantum vacuum with variable energy density is proposed. In this model, time we measure with clocks is only a mathematical parameter of changes running in quantum vacuum. Mass and gravity are carried by the variable energy density of quantum vacuum. Each elementary particle is a structure of quantum vacuum and diminishes the quantum vacuum energy density. Symmetry “particle – diminished energy density of quantum vacuum” is the fundamental symmetry of the universe which gives origin to the inertial and gravitational mass. Special relativity’s Sagnac effect in GPS system and important predictions of general relativity such as precessions of the planets, the Shapiro time delay of light signals in a gravitational field and the geodetic and frame-dragging effects recently tested by Gravity Probe B, have origin in the dynamics of the quantum vacuum which rotates with the earth.</p>

Optical and TEM characterization of phase transformation in Zn ion implanted and thermal oxidized quartz

<table class="data" width="100%"><tbody><tr valign="top"><td class="value"><p>Metal and metal oxide nanoparticles (NPs) embedded in various matrices have been the object of increasing interest due to their peculiar physical properties significantly different from the corresponding ones of bulk material. Metallic Zn NPs can be used in UV photo-detectors. Zinc oxide NPs play an important role too, since ZnO has direct band gap of 3.37eV, large exiton binding energy of 60meV, sorption effect, room temperature ferromagnetism and others. So they can be used in varies perspective electron devices. In this paper the optical parameters and transmission electron microscopy (TEM) characterization of Zn implanted quartz during NP formation at annealing are reported.</p><p>Optical-grade high-pure (OH^{<span style="font-size: small;">-</span>}: 50ppb) amorphous quartz slides were implanted by ^{<span style="font-size: small;">64</span>}Zn^{<span style="font-size: small;">+</span>} ions with fluence of 5×10^{<span style="font-size: small;">16</span>}/cm^{<span style="font-size: small;">2</span>} and energy of 50keV. To avoid the magnificent substrate heating during implantation the ion current density was less than 0.5μA/cm^{<span style="font-size: small;">2</span>}. Than the samples were subjected to isochronally during 1h oxidation in temperature ranges from 400 up to 800^{<span style="font-size: small;">o</span>}C. The Zn contained phase creation and its thermal evolution were investigated by recording the optical transmittance spectra at room temperature in a spectral range of 200-800nm and by photoluminescence at temperatures of 10-300K in a spectral range of 350-800nm using an illumination of He-Cd laser with wavelength of 325nm. Visualization and identification of NPs was made by study of the cross section samples TEM fitted with electron diffraction, an EDAX detector attachment for X-ray energy dispersive spectroscopy (EDS), and with a high angle annular dark field detector (HAADF) for scanning operation. The EDS maps of the element distribution and the NP sizes were determined in the scanning TEM regime.</p><p>As a result of these studies it was found that after the quartz implantation by ^{<span style="font-size: small;">64</span>}Zn^{<span style="font-size: small;">+</span>} ions with fluence of 5×10^{<span style="font-size: small;">16</span>}/cm^{<span style="font-size: small;">2</span>} and energy of 50keV the amorphous metallic Zn NPs with an average radius of 3 nm were created. During process of sequentially isochronally furnace annealing in oxygen atmosphere in 1h in temperature ranges from 400 up to 800^{<span style="font-size: small;">o</span>}C in samples there was phase transformation from metallic Zn phase to its oxide form. After annealing at 800^{<span style="font-size: small;">o</span>}C the Zn NPs transform to the ZnO or/and Zn_{<span style="font-size: small;">2</span>}SiO_{<span style="font-size: small;">4</span>} phase with average radius of 4,5nm.</p></td></tr></tbody></table><div id="indexing"><h4> </h4></div>

An Exact Analytical Solution to the Shallow Water Equations Near Beaches

<p>The nonlinear differential equation governing the dynamics of water waves can be well approximated by a linear counterpart in the case of shallow waters near beaches. The linear equation, which is of second order nature, cannot be exactly solved in many apparently simple cases. In our work, we consider the shape of system as a complete second-order polynomial which contains the constant (step-like), linear and quadratic shapes near the beach. We then apply some novel transformations and transform the problem into a form which can be solved in an exact analytical manner via the powerful Nikiforov-Uvarov technique. The eigenfunctions of the problem are obtained in terms of the Jacobi polynomials and the eigenvalue equation is reported for any arbitrary mode. </p>