background: the presence of heavy metals in the environment especially in water supplies have caused many concerns because of their toxicity and non-degradability. hexavalent chromium (cr) is one of the most toxic metals which is used in many industries, so it is essential to remove it from industrial wastewater. in this study, we made a comparison between different adsorption isotherms in the ...

Under irradiation, chemical species can redistribute in ways not expected from equilibrium behavior. In oxide-dispersed ferritic alloys, the phenomenon of irradiation-induced Cr redistribution at the metal/oxide interfaces has drawn recent attention. Here, the thermal and irradiation stability of the FeCr/Y2O3 interface has been systematically studied. Trilayer thin films of 90 nm Fe - 20 at.% ...

algae have been proven efficient biological vectors for heavy metal uptake. in order to further study their biosorption potential, two strains spirogyra sp. and spirulina sp. have been studied under different initial metal concentrations. in recent years, the biosorption processes have been studied extensively using microbial biomass as biosorbent for heavy metal ions removal. in these studies...

A self-assembled modified Pleurotus Cornucopiae material (SMPM) combined with improved Intermittent Bubbling Fluidized Bed (IBFB) was investigated to remove the hexavalent chromium ions in aqueous solution. After the modification, the powder-like raw material gradually self-assembled together to SMPM, which had crinkly porous structure, improved the Cr-accommodation ability in a sound manner. O...

Daily industrial activities especially in developing countries produce and discharge wastes containing heavy metals into the water resources making them polluted, threatening human health ecosystem. One such metal is Chromium, hexavalent form of which extremely toxic carcinogenic. Biosorption, process passive cation binding by dead or living biomass, represents a potentially cost-effective way ...

Various pollutants (e.g. boron and hexavalent chromium) are introduced into the aquatic environment from a variety of industrial operations causing damages to environment and affecting human health. Boron in irrigation water is of particular interest because it can have beneficial or toxic effect on plants, depending on its concentration. Pollution of the environment with hexavalent chromium (C...

Chromium has been and is extensively used worldwide in multiple industrial processes and is routinely discharged to the environment from such processes. Therefore, this heavy metal is a potential threat to the environment and to public health, primarily because it is non-biodegradable and environmentally persistent. Chromium exists in several oxidation states, the most stable of which are triva...

The first principles calculations of the electronic structure and hyperfine interactions Cr $$_x$$ NbSe $$_2$$ (x = 0.33, 0.55) chalcogenides are presented. As a result, values fields parameters quadrupole interaction were determined for different arrangements chromium ions. Ab initio compared with data obtained by nuclear magnetic resonance methods on $$^{53}$$ $$^{93}$$ Nb nuclei. It has been...

Objectives: The purpose of this study was to analyze, with the aid of scanning electron microscopy (SEM), the chemical and structural changes in metal brackets subjected to an in vitro biodegradation process. Methods: The sample was divided into three groups according to brackets commercial brand names, i.e., Group A = Dyna-Lock, 3M/Unitek (AISI 303) and Group B = LG standard edgewise, American...

Several metal or metalloid ions exist in multiple oxidation states and can undergo electron transfer reactions that are important in biological and environmental systems. There are endogenous metal ions such as iron, copper, and cobalt that participate in oxidation-reduction reactions with species of oxygen like molecular dioxygen, superoxide, and hydrogen peroxide. These reactions may be modul...