Change in the Shape of Nuclei in the Chains of Krypton,Strontium, Zirconium,Molybdenum, and Ruthenium Isotopes in the Relativistic-Mean-Field Approximation

Physics of Atomic Nuclei - Changes in the shape of nuclei in the chains of even—even crypton, strontium, zirconium, molybdenum, and ruthenium isotopes are studied on the basis of the...     

Evaluation of distribution and bioavailability of Cr,Mn, Fe,Cu, Zn and Pb in the waters of the upper course of the Lerma River

Distribution and bioavailability of Cr, Mn, Fe, Cu, Zn, and Pb in the waters of the upper course of the Lerma River (UCLR), Mexico, were evaluated by means total reflection x‐ray fluorescence spectrometry. The surface water samples were collected from eight sites distributed along the flow direction of the river. Four sampling campaigns were carried out in each site during a one‐year period. The water samples were analyzed in triplicate, using a TXRF Spectrometer ‘TX‐2000 Ital Structures’ with a Si(Li) detector and a resolution of 140 eV (FWHM) at Mn Kα. A Mo tube (40 kV, 30 mA) with 17.4 KeV excitation energy was used for a counting time of 500 s. Results show that the concentration ranges of heavy metals in the water are the following: Cr, from < 5 to 56 µg/l; Mn, from 9 to 788 µg/l; Fe, from 98 to 8474 µg/l; Cu, from 10 to 225 µg/l; Zn, from 23 to 189 µg/l and Pb, from < 3 to 30 µg/l. There are significant statistical differences in the concentration of heavy metals between the different sampling sites and between the different sampling campaigns. The Pearson correlation results indicate a strong correlation between some heavy metals in the water, this significant correlation (p < 0.05) indicating a natural or/and a shared contamination source for these metals. Metal concentration in the water mostly did not exceed the guide values given by Mexican regulation for agricultural use. Only Cu, Mn and Fe in total water phase exceeded the maximum permissible limits for irrigation proposes at some sites. Copyright © 2007 John Wiley & Sons, Ltd.     

Anomalies of density, stresses, and the gravitational field in the interior of mars

We determined the possible compensation depths for relief harmonics of different degrees and orders. The relief is shown to be completely compensated within the depth range of 0 to 1400 km. The lateral distributions of compensation masses are determined at these depths and the maps are constructed. The possible nonisostatic vertical stresses in the crust and mantle of Mars are estimated to be 64 MPa in compression and 20 MPa in tension. The relief anomalies of the Tharsis volcanic plateau and symmetric feature in the eastern hemisphere could have arisen and been maintained dynamically due to two plumes in the mantle sub-stance that are enriched with fluids. The plumes that originate at the core of Mars can arise and be maintained by the anomalies of the inner gravitational field achieving +800 mGal in the region of plume formation, ?1200 mGal above the lower mantle-core transition layer, and ?1400 mGal at the crust.     

Cluster structure of the surface in the amorphous,quasicrystalline, and liquid states

The electronic structure of the Zr₆₀Ni₂₀Ti₂₀, Al₆₅Cu₂₀Fe₁₅, and Al₈₆Mn₁₄ systems has been investigated by X-ray photoelectron spectroscopy and band calculations of the total and partial densities of electronic states have been carried out by the TB-LMTO-ASA method with the aim of studying the chemical bonds and the nearest environment of atoms in the liquid, amorphous, and quasicrystalline states. A direct proof of the inheritance of the chemical structure of the liquid state in the amorphous and quasicrystalline states has been obtained for the first time. The similarity of the electronic structure and the nearest environment of atoms indicates identity of clusters in the liquid, amorphous, and quasicrystalline states. The degree of hybridization of valence electrons of atoms in clusters increases in going from the quasicrystalline to the amorphous state due to the increase the number of transition metal atoms in clusters.     

Indices of refraction of ZnS,ZnSe, ZnTe,CdS, and CdTe in the far infrared

The indices of refraction of pure ZnS, ZnSe and ZnTe at 2, 80, and 300°K have been measured in the spectral region from 10 to 100 cm^-1. The indices of refraction can be described by the simple dispersion formula for an undamped harmonic oscillator. The static dielectric constants of these materials are obtained from the best fit parameters using a simple dispersion equation. The average indices of refraction of pure CdS and CdTe at 5°K in the spectral region from 10 to 100 cm^-1 have also been measured.     

Sources and circulation of water and arsenic in the Giant Mine, Yellowknife, NWT, Canada

Recovery of gold from arsenopyrite-hosted ore in the Giant Mine camp, Yellowknife, NWT, Canada, has left a legacy of arsenic contamination that poses challenges for mine closure planning. Seepage from underground chambers storing some 237,000 tonnes of arsenic trioxide dust, has As concentrations exceeding 4000 ppm. Other potential sources and sinks of As also exist. Sources and movement of water and arsenic are traced using the isotopes of water and sulphate. Mine waters (16 ppm As; AsV/AsIII approximately 150) are a mixture of two principal water sources--locally recharged, low As groundwaters (0.5 ppm As) and Great Slave Lake (GSL; 0.004 ppm As) water, formerly used in ore processing and discharged to the northwest tailings impoundment (NWTP). Mass balance with delta18O shows that recirculation of NWTP water to the underground through faults and unsealed drillholes contributes about 60% of the mine water. Sulphate serves to trace direct infiltration to the As2O3 chambers. Sulphate in local, low As groundwaters (0.3-0.6 ppm As; delta34SSO4 approximately 4% and delta18OSO4 approximately -10%) originates from low-temperature aqueous oxidation of sulphide-rich waste rock. The high As waters gain a component of 18O-enriched sulphate derived from roaster gases (delta18OSO4) = + 3.5%), consistent with their arsenic source from the As2O3 chambers. High arsenic in NWTP water (approximately 8 ppm As; delta18OSO4 = -2%) derived from mine water, is attenuated to close to 1 ppm during infiltration back to the underground, probably by oxidation and sorption by ferrihydrite.     

Semi-leptonic decays in the model of Bars,Halpern, and Yoshimura

Semi-leptonic decays are investigated in the gauge theory of Bars, Halpern and Yo Yoshimura, using elementary baryons rather than quarks. It is proved that in order to get a correct d/f ratio in these decays it is necessary to use an (8,8) spin-zero hadron field, together with another multiplet of spin-zero hadrons. The tree approximation is shown not to be sufficient to calculate the decay amplitudes correctly.     

Sources and circulation of water and arsenic in the Giant Mine,Yellowknife, NWT,Canada

Recovery of gold from arsenopyrite-hosted ore in the Giant Mine camp, Yellowknife, NWT, Canada, has left a legacy of arsenic contamination that poses challenges for mine closure planning. Seepage from underground chambers storing some 237,000 tonnes of arsenic trioxide dust, has As concentrations exceeding 4000 ppm. Other potential sources and sinks of As also exist. Sources and movement of water and arsenic are traced using the isotopes of water and sulphate. Mine waters (16 ppm As; As^V/As^III ≈ 150) are a mixture of two principal water sources – locally recharged, low As groundwaters (0.5 ppm As) and Great Slave Lake (GSL; 0.004 ppm As) water, formerly used in ore processing and discharged to the northwest tailings impoundment (NWTP). Mass balance with δ¹⁸O shows that recirculation of NWTP water to the underground through faults and unsealed drillholes contributes about 60% of the mine water. ;[emsp]>Sulphate serves to trace direct infiltration to the As₂O₃ chambers. Sulphate in local, low As groundwaters (0.3–0.6 ppm As; δ³⁴S_SO4  ～ 4 ‰ and δ¹⁸O_SO4  ～ ? 10 ‰) originates from low-temperature aqueous oxidation of sulphide-rich waste rock. The high As waters gain a component of ¹⁸O-enriched sulphate derived from roaster gases (δ¹⁸O_SO4  = + 3.5 ‰), consistent with their arsenic source from the As₂O₃ chambers. High arsenic in NWTP water (～ 8 ppm As; δ¹⁸O_SO4  = ? 2 ‰) derived from mine water, is attenuated to close to 1 ppm during infiltration back to the underground, probably by oxidation and sorption by ferrihydrite.     

Measurement of the muonic x-ray cascade in Mg,AI, In,Ho, and Au

The muonic x-ray cascades in metallic targets of Mg, Al, In, Ho, and Au have been measured with Ge detectors. X-ray intensities from levels with principal quantum numbers up ton=15 were determined. Radiative Coulomb capture of muons to low lying levels was searched for but not found. The experimental intensities could be reproduced by cascade calculations starting atn=20 with properly chosen initial angular momentum distributions, either modified statistical or — in the case of Ho —linear. The electronicK refilling rates for Mg and Al were found to be roughly only one third of the refilling rates for aK hole in an ordinary atom. The full refilling rate, however, is adequate for the heavier elements.     

EDM of the muon, deuteron, and proton in storage rings

I discuss the progression of ideas over the last decade that has led to extremely sensitive dedicated electric dipole moment (edm) storage ring designs. These ideas grew out of our experience in BNL E821: a precision measurement of the anomalous magnetic moment of the muon (Bennett et al. Phys Rev D73:072003, 2006).     

Superconductivity,ferromagnetism, and antiferromagnetism in the Hubbard model

Using the simplest one-loop approximation, it is possible to observe both ferromagnetic and antiferromagnetic nonoverlapping parts of the phase diagram, each of which overlaps with the domain of existence of the superconducting ordering.