288 research outputs found
Algae bioaccumulation capacity for metals in acid mine drainage (AMD)-a case study in Frongoch Mine, the UK
Algae living in the AMD water around the Frongoch Mine, the UK, were collected
and identified by microscope. Metals’ concentration was evaluated in AMD water
and algae in two seasons (June and October) in 2019 to assess the bioaccumulation
capacity of algae. Two types of algae, Ulothrix sp. and Oedogonium sp., were found to
be the main species at the Frongoch mine, and they revealed a high capacity of metals
bioaccumulation. Concentrations of metals in AMD water from higher to lower were
Zn>>Pb>Cd>Fe>Cu. Study results identified the bioaccumulated metals concentrations
in algae from higher to lower were Fe>Pb>Cu>Cd>Zn
Bioaccumulation of metals by algae from acid mine drainage: a case study of Frongoch Mine (UK)
In Frongoch Mine (UK), it is unclear the distribution of metals on indigenous algae and whether these species of algae can accumulate metals. This study aimed to investigate the role of indigenous algae for metal removal from acid mine drainage and understand if metals can be adsorbed on the surface of algae or/and bioaccumulated in algae. A sequential extraction procedure was applied for algae samples collected from acid mine drainage (AMD) water to identify the forms in which metals are found in algae. Concentrations of Fe, Pb, Zn, Cu and Cd were evaluated in the algae and AMD samples were collected in June and October 2019. AMDs samples had a pH value ranging between 3.5 and 6.9 and high concentrations of Zn (351 mg/L) and Pb (4.22 mg/L) that exceeded the water quality standards (Water Framework Directive, 2015). Algae Ulothrix sp. and Oedogonium sp. were the two main species in the Frongoch AMDs. The concentrations of metals in algae ranged from 0.007 to 51 mg/g, and the bioconcentration factor of metals decreased in the following order: Fe > > Pb > > Cu > Cd > Zn. It was found that Zn, Cu and Cd were adsorbed onto the surface of and bioaccumulated in the algae, while Pb and Fe were mainly bioaccumulated in the algae. Indigenous algae can be considered as a biogeochemical barrier where metals are accumulating and can be used in bioremediation methods. Also, indigenous algae could be used as a bioindicator to assess water pollution at Frongoch Mine and other similar metal mines
Bioaccumulation of metals by algae from acid mine drainage:a case study of Frongoch Mine (UK)
In Frongoch Mine (UK), it is unclear the distribution of metals on indigenous algae and whether these species of algae can accumulate metals. This study aimed to investigate the role of indigenous algae for metal removal from acid mine drainage and understand if metals can be adsorbed on the surface of algae or/and bioaccumulated in algae. A sequential extraction procedure was applied for algae samples collected from acid mine drainage (AMD) water to identify the forms in which metals are found in algae. Concentrations of Fe, Pb, Zn, Cu and Cd were evaluated in the algae and AMD samples were collected in June and October 2019. AMDs samples had a pH value ranging between 3.5 and 6.9 and high concentrations of Zn (351 mg/L) and Pb (4.22 mg/L) that exceeded the water quality standards (Water Framework Directive, 2015). Algae Ulothrix sp. and Oedogonium sp. were the two main species in the Frongoch AMDs. The concentrations of metals in algae ranged from 0.007 to 51 mg/g, and the bioconcentration factor of metals decreased in the following order: Fe > > Pb > > Cu > Cd > Zn. It was found that Zn, Cu and Cd were adsorbed onto the surface of and bioaccumulated in the algae, while Pb and Fe were mainly bioaccumulated in the algae. Indigenous algae can be considered as a biogeochemical barrier where metals are accumulating and can be used in bioremediation methods. Also, indigenous algae could be used as a bioindicator to assess water pollution at Frongoch Mine and other similar metal mines
Maxwell Equations in Complex Form of Majorana - Oppenheimer, Solutions with Cylindric Symmetry in Riemann S_{3} and Lobachevsky H_{3} Spaces
Complex formalism of Riemann - Silberstein - Majorana - Oppenheimer in
Maxwell electrodynamics is extended to the case of arbitrary pseudo-Riemannian
space - time in accordance with the tetrad recipe of Tetrode - Weyl - Fock -
Ivanenko. In this approach, the Maxwell equations are solved exactly on the
background of static cosmological Einstein model, parameterized by special
cylindrical coordinates and realized as a Riemann space of constant positive
curvature. A discrete frequency spectrum for electromagnetic modes depending on
the curvature radius of space and three parameters is found, and corresponding
basis electromagnetic solutions have been constructed explicitly. In the case
of elliptical model a part of the constructed solutions should be rejected by
continuity considerations. Similar treatment is given for Maxwell equations in
hyperbolic Lobachevsky model, the complete basis of electromagnetic solutions
in corresponding cylindrical coordinates has been constructed as well, no
quantization of frequencies of electromagnetic modes arises.Comment: 39 page
Influence of chlorine on the fate of Pb and Cu during clinkerization
The fate of heavy metals during clinkerization is of crucial significance to the utilization of solid waste as fuels and raw materials in cement kiln producing clinker. A ternary system of clinker-heavy metal-chlorine was developed that is more coincident with the condition of co-processing of solid waste in cement kiln. The main goal of this study was to investigate the relationships among chlorine, volatilization and solidification of Cu/Pb, and mineral phases of the clinker during clinkirization. The AlCl3·6H2O (chlorine source) and PbO/CuO were mixed with cement raw meal in appropriate ratios to produce co-processed clinkers. The volatilization and solidification of Pb and Cu were investigated experimentally using a combination of atomic absorption spectrometry, electron probe micro-analysis, scanning electron microscopy with energy-dispersive X-ray spectroscopy, optical microscope, thermogravimetric and X-ray diffraction quantitative analyses. The volatilization ratios of Pb and Cu increased up to 46.18% and 34.04%, respectively, with increasing AlCl3·6H2O content up to 1.6%. comparing to the cement mixtures without AlCl3·6H2O addition (Pb and Cu volatilisation ratios are 49.90% and 27.21%, respectively). Pb and Cu oxides can be transformed into Pb and Cu chlorides, that are not stable and have high vapor pressure. Pb and Cu are mainly concentrated in the interstitial phases of the clinker. The addition of AlCl3·6H2O led to increase the crystal size of alite and belite. X-ray diffraction quantitative analyses proved that the content of silicate phase increased with the corresponding content of interstitial phases decreased during clinkerization with the addition of AlCl3·6H2O, that decreased the ability of clinker to solidify Pb and Cu in the produced clinkers. This research can help to promote understanding of the fate of heavy metals during the cement kiln co-processing of solid wastes and meaningfully for energy conservation and sustainable development
Characteristics of anisotropic media over hydrocarbons in the mode of frequency-modulated signals
The article considers the impact of frequency-modulated signals on an anisotropic medium over oil and gas deposits. Modeling of the components of the tensors of the dielectric constant of the medium over hydrocarbon deposits was carried out. The characteristics of the medium over accumulations of hydrocarbons for frequency-modulated signals from the frequency of the carrier oscillation, the frequency modulation index for the right and left polarizations of electromagnetic waves are studied. Methods of searching for hydrocarbons based on the variation in the characteristics of the applied signals are recommended. It is proposed to introduce new search modes to improve the accuracy of determining the boundaries of hydrocarbon deposits. The influence pattern of the dielectric constant of an anisotropic medium on the real and phase components of the tensor components are established. The research results can be applied in the electrical exploration of minerals
Characteristics of anisotropic media over hydrocarbons in the mode of frequency-modulated signals
The article considers the impact of frequency-modulated signals on an anisotropic medium over oil and gas deposits. Modeling of the components of the tensors of the dielectric constant of the medium over hydrocarbon deposits was carried out. The characteristics of the medium over accumulations of hydrocarbons for frequency-modulated signals from the frequency of the carrier oscillation, the frequency modulation index for the right and left polarizations of electromagnetic waves are studied. Methods of searching for hydrocarbons based on the variation in the characteristics of the applied signals are recommended. It is proposed to introduce new search modes to improve the accuracy of determining the boundaries of hydrocarbon deposits. The influence pattern of the dielectric constant of an anisotropic medium on the real and phase components of the tensor components are established. The research results can be applied in the electrical exploration of minerals
The Coulomb-Oscillator Relation on n-Dimensional Spheres and Hyperboloids
In this paper we establish a relation between Coulomb and oscillator systems
on -dimensional spheres and hyperboloids for . We show that, as in
Euclidean space, the quasiradial equation for the dimensional Coulomb
problem coincides with the -dimensional quasiradial oscillator equation on
spheres and hyperboloids. Using the solution of the Schr\"odinger equation for
the oscillator system, we construct the energy spectrum and wave functions for
the Coulomb problem.Comment: 15 pages, LaTe
- …