Losses Of Cu Research Articles

VEGETATIVE FILTER STRIP REMOVAL OF METALS IN RUNOFF FROM POULTRY LITTER-AMENDED FESCUEGRASS PLOTS

Runoff from land areas amended with poultry (Gallus gallus domesticus) manure can contain elevated concentrations of metals such as Cu, Fe, and Zn. Vegetative filter strips (VFS) can reduce runoff concentrations of animal manure components, but reported studies have typically focused on nutrients and solids rather than metals. This experiment assessed the impact of VFS length (0 to 12 m) on concentrations and mass losses of Cu, Fe, K, Na, Ni, and Zn in runoff from fescuegrass (Festuca arundinacea Schreb.) plots (1.5 m wide ×6 and 12 m long) treated with poultry litter. The runoff was produced from simulated rainfall applied at 50 mm h–1 until 1 h of runoff had occurred. Runoff Ni concentrations were below detection levels in all cases. Concentrations of Cu, Fe, K, Na, and Zn did not differ between litter-treated plot lengths but were significantly (p <0.001) affected by VFS length, decreasing in an approximately firstorder fashion. Means separation indicated that concentrations of Cu, Fe, K, and Zn did not significantly decrease after a VFS length of 3 m, while Na concentrations decreased up to a VFS length of 6 m. Mass transport of only Cu significantly decreased with increasing VFS, suggesting that VFS removal mechanisms such as adsorption to clay particles might play a larger role with regard to Cu than to Fe, K, Na, and Zn.

The Crummock Water aureole: a zone of metasomatism and source of ore metals in the English Lake District

The Crummock Water aureole, an ENE-trending elongate zone of bleached and recrystallized Skiddaw Group rocks, 24 km in length and up to 3 km wide, is a zone in which pervasive metasomatism has modified the composition of the dominantly siltstone and mudstone lithologies. The bleached rocks show a substantial net gain of As, B, K and Rb and loss of Cl, Ni, S, Zn, H 2 O and C. Carbon loss is responsible for the bleaching. There are smaller and more localized net losses of Cu, Fe, Li and Mn, and gains of Ca, F and Si, whilst Co, Pb and REE are at least locally redistributed. Many chalcophile elements show evidence of initial widespread depletion and subsequent local enrichment. The mineralogy of the rocks is little affected by the geochemical changes. Like their counterparts outside of the bleached zone, the metasomatized rocks consist essentially of quartz, chlorite, muscovite, paragonite and rutile. Small aggregates and porphyroblasts of white mica and chlorite are developed. The metasomatism, which was accompanied by tourmaline veining, is superimposed on a contact metamorphic event. It post-dates the main Caledonian cleavage but pre-dates late Caledonian minor folds. Rb-Sr whole rock isochrons suggest that the metasomatic event occurred at c. 400 Ma and was thus associated with the Lower Devonian Shap-Skiddaw granite magmatism and not the earlier Eskdale Granite or Ennerdale Granophyre magmatic events. Modelling of Bouguer anomalies indicates that geological and geochemical constraints are most simply satisfied if the metasomatism is attributed to a buried, elongate, highly evolved granitic body intruded along the northern margin of a major granitic-granodioritic component of the Lake District batholith. The bleached zone is associated with a major lineament, which may reflect basement control on the location and form of the buried intrusion. Loss of metals from the bleached rocks is related to penecontemporaneous and subsequent hydrothermal vein mineralization and demonstrates that Skiddaw Group sedimentary rocks were a source of ore metals in the Lake District.

Wet ashing in biological samples in a microwave oven under pressure using poly(tetrafluoroethylene) vessels.

Gorsuch has described the problems associated with the oxidation of organic matter in biological samples. This is a step that must precede trace metal determination by atomic spectroscopy. Treatment with acid on a hot plate typically requires 1-2 h. The use of a microwave oven is an attractive possibility for acceleration of the process. Koirtyohann et al. and Barrett et al. modified microwave ovens by adding an exhaust port. Nadkarni exploited an unmodified oven by using a Pyrex vacuum desiccator as a pressurizable vessel. They report significant losses of Cu (26%) and Pb (20%). Matts et al. tried polycarbonate pressurizable vessels, but the plastic quickly became opaque and brittle. The authors have reevaluated the prospects for use of an unmodified microwave oven with pressurized vessels. They found that Pyrex vessels gain heat in the glass quickly. The authors substituted Teflon TFA brand fluorocarbon resin for polycarbonate and find it has superior chemical and mechanical properties. They now report a 60-s pressure vessel procedure using an unmodified commercial oven.

The Cae Coch volcanogenic massive sulphide deposit, Trefriw, North Wales

The Cae Coch massive pyrite deposit is described and re-interpreted as a sedimentary volcanogenic orebody of about 200 000 tons. It is located at the contact between the Ordovician Dolgarrog Volcanic Formation (basic tuffs and lavas) and the overlying Llanrychwyn Slates (pyritic black mudstone) and close to a major intrusive rhyolite. The minerals are dominantly pyrite and quartz with minor molybdenite and the deposit shows zonal variation in trace Ba, Cu, Zn, Ni, and Co and detectable concentrations of Sn, TI, Hg and Ag. The footwall rocks have been highly altered and the basic rocks show increases in K, Ba, S and carbonate and losses of Cu, V and Co and probably light rare earth elements (LREE). A progressive gain in K, Ba and Pb and a depletion of Ga, Sr, Sn, Zn and REE is observed with increasing alteration of the rhyolite. The deposit is concluded to be the result of accumulation in a brine pool but with a component of debris flow of uncertain provenance. The deposit resembles Kuroko style mineralization and seems to be unique in the immediate district.

帯溶融条件によるAlnico-8磁石合金の磁気特性

It is well known that cast structure and crystal orientation influence strongly the magnetic properties of Alnico-type magnet alloy. The behaviors of magnetic properties of Alnico-8 magnet alloy prepared under various zone melting conditions of the horizontal type apparatus have been investigated. The results obtained are as follows: Magnetic properties and the crystal structure of these alloys are affected considerably by the traveling rate of the heating coil. The magnetic properties are remarkably deteriorated at a traveling rate of about 20 mm/hr. In this case, many crystals of the dendritic structure are observed microscopically and conic columnar crystals inclining 14∼20° to the specimen axis are observed macroscopically.When zone melting proceeds in the temperature range of 1330∼1350°C, satisfactory magnetic properties are obtained. As the temperature of the melting zone is raised in vacuum, melting losses of Cu and Al show a remarkable increase as high as of about 50%.

Characteristic energy losses of low-energy electrons reflected from aluminium and copper

The characteristic energy loss spectra of electrons reflected from freshly evaporated Al and Cu specimens have been measured for various primary electron energies in the range 9-265 ev. Contrary to expectation the ratio of the intensity of the 10 ev surface plasma loss to that of the 15 ev volume loss in Al, for electrons scattered through 90°, is found to decrease with decreasing primary energy in the range from about 240 ev to 80 ev. This appears to be due to the behaviour of the surface loss, which decreases rapidly in intensity with decreasing primary energy. Both the surface and volume plasma losses of Al cease to be excited when the primary energy is less than about 26-29 ev, the surface loss cutting off at a slightly lower primary energy than the volume loss. The modified surface loss of Al resulting from oxidation of the specimen surface is observed at 7.1 ev, and the half-width of the 10 ev surface loss increases from 3.8 ev to 5.3 ev with increasing surface oxidation, indicating that the surface plasma oscillations are damped by the contamination. The energy losses of Cu have been investigated by observing their intensity dependence on (i) the primary electron energy for a fixed scattering angle of 90° and (ii) the electron scattering angle for various fixed primary energies, scattering angles of 90° and 20° being employed. The results indicate that a loss observed at 3.5 ev is possibly due to excitation of surface plasma oscillations.