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A polycrystalline sample LuCrO3 has been characterized by neutron powder diffraction (NPD) and magnetization measurements. Its crystal structure has been Rietveld refined from NPD data in space group Pnma; this perovskite contains strongly tilted CrO6 octahedra with extremely bent Cr-O-Cr superexchange angles of ∼142°. The NPD data show that below Néel temperature (TN ≃ 131 K), the magnetic structure can be defined as an A-type antiferromagnetic arrangement of Cr3+ magnetic moments, aligned along the b axis, with a canting along the c axis. A noticeable magnetostrictive effect is observed in the unit-cell parameters and volume upon cooling down across TN. The AC magnetic susceptibility indicates the onset of magnetic ordering below 112.6 K; the magnetization isotherms below TN show a nonlinear behaviour that is associated with the described canting of the Cr3+ magnetic moments. From the Curie-Weiss law, the effective moment of the Cr3+ sublattice is found to be µeff = 3.55 µB (calculated 3.7 µB) while the ΘCW parameter yields a value of -155 K, indicating antiferromagnetic interactions. There is a conspicuous increase of TN upon the application of external pressure, which must be due to shortening of the Cr-O bond length under compression that increases the orbital overlap integral.

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Arsenic-hyperaccumulator Pteris vittata exhibits remarkable absorption ability for chromium (Cr) while beneficial element selenium (Se) helps to reduce Cr-induced stress in plants. However, the effects of Se on the Cr uptake and the associated mechanisms in P. vittata are unclear, which were investigated in this study. P. vittata plants were grown for 14 days in 0.2-strength Hoagland solution containing 10 (Cr10) or 100 µM (Cr100) chromate (CrVI) and 1 µM selenate (Se1). The plant biomass, malondialdehyde contents, total Cr and Se contents, Cr speciation, expression of genes associated with Cr uptake, and Cr subcellular distribution in P. vittata were determined. P. vittata effectively accumulated Cr by concentrating 96-99% in the roots under Cr100 treatment. Further, Se substantially increased its Cr contents by 98% to 11,596 mg kg-1 in the roots, which may result from Se's role in reducing its oxidative stress as supported by 27-62% reduction in the malondialdehyde contents. Though supplied with CrVI, up to 98% of the Cr in the roots was reduced to insoluble chromite (CrIII), with 83-89% being distributed on root cell walls. Neither Cr nor Se upregulated the expression of sulfate transporters PvSultr1;1-1;2 or phosphate transporter PvPht1;4, indicating their limited role in Cr uptake. P. vittata effectively accumulates Cr in the roots mainly as CrIII on cell walls and Se effectively enhances its Cr uptake by reducing its oxidative stress. Our study suggests that Se can be used to enhance P. vittata Cr uptake and reduce its oxidative stress, which may have application in phytostabilization of Cr-contaminated soils.

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Texture stands as a fundamental descriptor in the realms of geology and earth and planetary science. Beyond offering insights into the geological processes underlying mineral formation, its characterization plays a pivotal role in advancing engineering applications, notably in mining, mineral processing, and metal extraction, by providing quantitative data for predictive modeling. Laboratory diffraction contrast tomography (LabDCT), a recently developed 3D characterization technique, offers nondestructive measurement of grain phases including their morphology, distribution, and crystal orientation. It has recently shown its potential to assess 3D textures in complex natural rock samples. This study looks at improving on previous work by examining the artifacts and presents a novel postprocessing workflow designed to correct them. The workflow is developed to rectify inaccurate grain boundaries and interpolate partially reconstructed grains to provide more accurate results and is illustrated using multi-scan examples on chromite sands and natural chromitite from the Upper Group 2 Reef layer in South Africa. The postcorrected LabDCT results were validated through qualitative and quantitative assessment using 2D electron back-scattered diffraction on polished sample surfaces. The successful implementation of this postprocessing workflow underscores its substantial potential in achieving precise textural characterization and will provide valuable insights for both earth science and engineering applications.

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This research investigates the adsorption potential of chrysotile and lizardite, two minerals derived from chromite ore wastes, for the uptake of Methylene Blue (MB) dye from waste streams. The characterization of these minerals involves XRD, XRF, FTIR, and SEM. Results confirm the dominance of polymorphic magnesium silicate minerals, specifically chrysotile and lizardite, in the samples. The FTIR spectra reveal characteristic vibration bands confirming the presence of these minerals. The SEM analysis depicts irregular surfaces with broken and bent edges, suggesting favorable morphologies for adsorption. N2 adsorption-desorption isotherms indicate mesoporous structures with Type IV pores in both adsorbents. The Central Composite Design approach is employed to optimize MB adsorption conditions, revealing the significance of contact time, adsorbent mass, and initial MB concentration. The proposed models exhibit high significance, with F-values and low p-values indicating the importance of the studied factors. Experimental validation confirms the accuracy of the models, and the optimum conditions for MB adsorption are determined. The influence of solution acidity on MB uptake is investigated, showing a significant enhancement at higher pH values. Isothermal studies indicate Langmuir and Freundlich models as suitable descriptions for MB adsorption onto chrysotile and lizardite. The maximum adsorption capacities of MB for chrysotile and lizardite were found to be 352.97 and 254.85, respectively. Kinetic studies reveal that the pseudo-first-order model best describes the adsorption process. Thermodynamic analysis suggests an exothermic and spontaneous process. Statistical physics models further elucidate the monolayer nature of adsorption. Additionally, an artificial neural network is developed, exhibiting high predictive capability during training and testing stages. The reusability of chrysotile and lizardite is demonstrated through multiple regeneration cycles, maintaining substantial adsorption potential. Therefore, this research provides comprehensive insights into the adsorption characteristics of chrysotile and lizardite, emphasizing their potential as effiective and reusable sorbents for MB uptake from wastewater.

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Understanding how minerals are spatially distributed within natural materials and their textures is indispensable to understanding the fundamental processes of how these materials form and how they will behave from a mining engineering perspective. In the past few years, laboratory diffraction contrast tomography (LabDCT) has emerged as a nondestructive technique for 3D mapping of crystallographic orientations in polycrystalline samples. In this study, we demonstrate the application of LabDCT on both chromite sand and a complex chromitite sample from the Merensky Reef (Bushveld Complex, South Africa). Both samples were scanned using LabDCT and Electron Backscatter Diffraction (EBSD), and the obtained results were rigorously evaluated using a comprehensive set of qualitative and quantitative characterization techniques. The quality of LabDCT results was accessed by using the "completeness" value, while the inaccuracies were thoroughly discussed, along with proposed potential solutions. The results indicate that the grain orientations obtained from LabDCT are comparable to that of 2D EBSD but have the advantage of collecting true 3D size, shape, and textural information. This study highlights the significant contribution of LabDCT in the understanding of complex rock materials from an earth science perspective, particularly in characterizing mineral texture and crystallography in 3D.

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Chemical reduction combined with microbial stabilization is a green and efficient method for the remediation of hexavalent chromium (Cr(VI)) contaminated soil. In this study, the combination of ferrous sulfate with kitchen waste digestate was applied to reduce and immobilize Cr(VI) in chromite ore processing residue (COPR) contaminated soils, and systematically evaluated the remediation performance of Cr(VI) compared with several typical reducing agents (i.e., ferrous sulfate, zero valent iron, sodium thiosulfate, ferrous sulfide, and calcium polysulfide). The results showed that the combination of ferrous sulfate and digestate had superior advantages of a lower dosage of reducing agent and a long-term remediation effect compared to other single chemical reductants. Under an Fe(II):Cr(VI) molar ratio of 3:1% and 4% digestate (wt), the content of Cr(VI) in the soil decreased to 5.07 mg/kg after 60 days of remediation. Meanwhile, the leaching concentrations of Cr(VI) were below detection limit, which can meet the hazardous waste toxicity leaching standard. The risk level of Cr pollution was decreased from very high risk to low risk. The X-ray photoelectron spectroscopy (XPS) results further demonstrated that the combined treatments were beneficial to Cr(VI) reduction and stabilization. The abundance of bacteria with Cr(VI) reducing ability was higher than other treatments. Moreover, the high abundance of carbon and nitrogen metabolism in the combined treatments demonstrated that the addition of digestate was beneficial to the recovery and flourishing of Cr(VI)-reducing related microorganisms in COPR contaminated soils. This work provided an alternative way on Cr(VI) remediation in COPR contaminated soils.

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The high-temperature oxidation behavior of low-carbon steel (AISI 1015, AISI 8617, AISI 4115) was investigated over the temperature range from 600 to 1000 °C in humid air containing 25% water vapor. Mass gain of oxidation measurement was performed to study the oxidation kinetics. The microstructure, thickness, and composition of the oxide scale formed were investigated via optical microscope (OM), scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS), X-ray diffraction (XRD), and electron probe microanalyzer (EPMA). The oxidation process was performed from 2 to 100 min. As the oxidation time increased, the trend of mass gain per unit area switched from a linear to a parabolic law, regardless of the steel grade used. As the chromium content increased, the duration of time during which the oxidation rate followed a linear relationship decreased. In the low-alloy steel with higher chromium content, the thickness of the mixed oxide layer containing Cr increased and the oxidation rate decreased at all oxidation temperatures.

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In this study, Cr(VI)-contaminated soil mixed with COPR by using ferrous sulfate (FeSO4), enzyme residue (ER), and their combination under aerobic or anaerobic condition were investigated. The concentration of Cr(VI) decreased from 1498.05 to 104.63 mg kg-1 after the simultaneous addition of FeSO4 (30 %, w/w as FeSO4·7H2O) and ER (30 %, w/w) at 45 d under the anaerobic condition with a reduction efficiency of 93.02 %, which is higher than that by single FeSO4 (72.39 %) or ER (75.47 %) under the anaerobic condition. XRD, XPS, FTIR, and fluorescence spectroscopy were conducted to characterize soil and ER composition. Metagenomic analysis was performed to reveal the reduction mechanisms of FeSO4 and ER. The anaerobic condition with lower Eh was beneficial for Cr(VI) reduction than aerobic condition, and Eh was the main driver for the evolution of Cr(VI) reduction-related microorganisms. Moreover, the addition of ER enriched the organic matter and microbials in the soil. During the decomposition of organic matter under the anaerobic condition, organic acids were generated, leading to a decrease in pH and promoting the release of Cr(VI) from minerals. They also served as electron donors in Cr(VI) reduction. Additionally, the addition of excess FeSO4 stimulated the growth of iron-reducing bacteria and sulfate-reducing bacteria, facilitating to Cr(VI) reduction. Metagenomic analysis showed that Acinetobacter, related to the nemA and nfsA genes, was the dominant Cr(VI) reduction genus. Thus, the combination of FeSO4 and ER is a promising method for the remediation of Cr(VI)-contaminated soils mixed with COPR.

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The foundry industry generates large amounts of waste when casting metal into sand moulds. An important issue is the activities that are related to the re-recovery of the grain matrix (the main component of the moulding sand) for realising subsequent technological cycles. This process is particularly important in the case of the expensive chromite matrix that is necessary for use in manganese steel casting. The effects of the reclamation treatments of spent alkali-phenolic binder sand were evaluated by scanning electron microscopy with EDS, analysing the chemical composition in micro areas and proving the loss of binder on the surfaces of the matrix grains. Tests were also performed using the main criteria for evaluating a reclaimed organic binder: sieve analysis and ignition loss. A thermogravimetric analysis study was performed to assess the change in the chromite character of the grain matrix under the influence of temperature. The effects of the reclamation measures were verified by making moulding compounds on a matrix of reclaimed sand and a mixture of reclaimed and fresh sand. The tests and analyses that were carried out indicated the direction of an effective method for reclaiming used alkali-phenolic binder masses and the extent of the proportion of the regenerate in moulding sand in order to maintain the relevant technological parameters of the moulding sand.

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Potentially toxic elements (PTEs) contamination in the agricultural soil can generate a detrimental effect on the ecosystem and poses a threat to human health. The present work evaluates the PTEs concentration, source identification, probabilistic assessment of health hazards, and dietary risk analysis due to PTEs pollution in the region of the chromite-asbestos mine, India. To evaluate the health risks associated with PTEs in soil, soil tailings and rice grains were collected and studied. The results revealed that the PTEs concentration (mainly Cr and Ni) of total, DTPA-bioavailable, and rice grain was significantly above the permissible limit in site 1 (tailings) and site 2 (contaminated) as compared with site 3 (uncontaminated). The Free ion activity model (FIAM) was applied to detect the solubility of PTEs in polluted soil and their probable transfer from soil to rice grain. The hazard quotient values were significantly higher than the safe (FIAM-HQ < 0.5) for Cr (1.50E+00), Ni (1.32E+00), and, Pb (5.55E+00) except for Cd (1.43E-03), Cu (5.82E-02). Severity adjustment margin of exposure (SAMOE) results denote that the PTEs contaminated raw rice grain has high health risk [CrSAMOE: 0.001; NiSAMOE: 0.002; CdSAMOE: 0.007; PbSAMOE: 0.008] for humans except for Cu. The Positive matrix factorization (PMF) along with correlation used to apportion the source. Self-organizing map (SOM) and PMF analysis identified the source of pollution mainly from mines in this region. Monte Carlo simulation (MCS) revealed that TCR (total carcinogenic risk) cannot be insignificant and children were the maximum sufferers relative to adults via ingestion-pathway. In the spatial distribution map, the region nearer to mine is highly prone to ecological risk with respect to PTEs pollution. Based on appropriate and reasonable evaluation methods, this work will help environmental scientists and policymakers' control PTEs pollution in agricultural soils near the vicinity of mines.

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The mixture of H2 and CO, the so-called syngas, is the value-added product of H2O and CO2 co-electrolysis and the feedstock for the production of value-added chemicals (mainly through Fischer-Tropsch). The H2/CO ratio determines the process in which syngas will be utilized and the type of chemicals it will produce. In the present work, we investigate the effect of H2O/CO2 (steam/carbon dioxide, S/C) ratio of 0.5, 1 and 2 in the feed, on the electrochemical performance of an 8YSZ electrolyte-supported solid oxide cell and the H2/CO ratio in the outlet, under co-electrolysis at 900 °C. The B-site iron doped lanthanum strontium chromite La0.75Sr0.25Cr0.9Fe0.1O3-δ (LSCF) is used as fuel electrode material while as oxygen electrode the state-of-the art LSM perovskite is employed. LSCF is a mixed ionic-electronic conductor (MIEC) operating both under a reducing and oxidizing atmosphere. The cell is electrochemically characterized under co-electrolysis conditions both in the presence and absence of hydrogen in the feed of the steam and carbon dioxide mixtures. The results indicate that under the same concentration of hydrogen and different S/C ratios, the same electrochemical performance with a maximum current density of approximately 400 mA cm-2 is observed. However, increasing p(H2) in the feed results in higher OCV, smaller iV slope and Rp values. Furthermore, the maximum current density obtained from the cell does not seem to be affected by whether H2 is present or absent from the fuel electrode feed but has a significant effect on the H2/CO ratio in the analyzed outlet stream. Moreover, the H2/CO ratio seems to be identical under polarization at different current density values. Remarkably, the performance of the LSCF perovskite fuel electrode is not compromised by the exposure to oxidizing conditions, showcasing that this class of electrocatalysts retains their reactivity in oxidizing, reducing, and humid environments.

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Heavy metals exposure through dust emissions pose a health risk to workers in coal and chromite mines. The processes involved in mining are noteworthy for the generation of heavy metal-contaminated dust which causes human health implications, especially to the workers that are mainly exposed to such toxins. This study determined pollution levels in coal and chromite mines and calculated the health risk of workers being exposed to heavy metal-contaminated dust. We used fractioned dust with particle sizes < 75, 75-106, and 107-150 µm to assess the pollution levels, anthropogenic impacts, geo-accumulation index, and enrichment factor for selected coal and chromite mines. Through a probabilistic approach, Monte Carlo simulations were used to determine health risks. The findings revealed that the smallest size dust fraction (< 75 µm) contained the highest metal concentrations. Ingestion was considered a prominent exposure route contributing to health risk. In the dust fraction (< 75 µm), chromite mines exhibited the highest Cr (340.6 mg/kg) and lowest Cd (8.4 mg/kg) concentrations. In coal mines, Mn (284.9 mg/kg) and Cd (2.1 mg/kg) were measured highest and lowest, respectively. Pollution assessment revealed dust to be moderately polluted. Health risk assessment showed that Cr in chromite mines exhibited a mean HI value of 1.16E + 00 that was higher than the safe level (HI > 1) having the potential to cause significant health risk to workers. In coal mines, the estimated total HI was 6E-1. Sensitivity analysis revealed concentration and exposure time to be the most influential parameters contributing to risk. Therefore, governmental and nongovernmental organizations must develop dust pollution control guidelines and mitigation measures to safeguard the health of mineworkers by limiting heavy metal exposure.

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In order to realize the harmless and resource disposal of hazardous waste incineration residue (HWIR) and chromite ore processing residue (COPR), this paper prepares glass-ceramics by HWIR. The COPR was co-sintered with the base glass of HWIR to realize the solidification and stabilization of COPR. The results shown that the single-stage sintering method has a simple process and low energy consumption, while the two-stage sintering method has better mechanical properties. Chromium in COPR may be solidified/stabilized by physical encapsulation and chemical fixation. When the content of COPR reaches 50%, the leaching concentration of Cr and Cr(VI) in the solidified body of HWIR solidified COPR (IRSC) is less than 5 mg/L, which satisfies the US EPA and CN GB5085.3 standard limits. This study achieves waste control by waste and prepares solidified bodies (IRSC) with good mechanical properties, chemical corrosion resistance, and low leaching concentration of heavy metals, which provides feasibility for its engineering application.

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Tissue engineering combines suitable cells, engineering methods, and proper biochemical factors to develop functional and biological tissues and repair damaged tissues. In this study, we focused on synthesizing and characterizing a nanocomposite scaffold based on glycerol and azelaic acid (Gl-Az) combined with copper chromite (CuCr2O4) nanoparticles in order to increase the osteogenic differentiation efficiency of human adipose-derived stem cells (hADSCs) on fabricated scaffolds. The degradability and hydrophobicity properties as well as mechanical and thermal behaviors of nanocomposite scaffolds were investigated. Next, the cell toxicity of glycerol, azelaic acid and CuCr2O4 nanoparticles was studied by MTT assay test and acridine orange staining. Finally, the osteogenic differentiation of hADSCs on Gl-Az-CuCr2O4 scaffolds was examined using alkaline phosphatase activity (ALP) and calcium content. The obtained results demonstrated that Gl-Az-1%CuCr2O4 not only showed appropriate mechanical strength, biocompatibility and degradability but also influenced the capability of hADSCs to differentiate into osteogenic lineages. The hADSCs culture in Gl-Az-1%CuCr2O4 showed a significant increase in ALP activity levels and calcium biomineralization after 14 days of osteogenic differentiation. In conclusion, the Gl-Az-1%CuCr2O4 nanocomposite could be used as a biocompatible and degradable scaffold to induce the bone differentiation of hADSCs and it could be a promising scaffold in bone regenerative medicine.

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The reduced chromite ore processing residue (rCOPR) deposited in environments is susceptible to surrounding factors and causes reoccurrence of Cr(VI). However, the impact of natural sunlight on the stability of rCOPR is still unexplored. Herein, we investigated the dissolution and transformation behaviors of Cr(III)-Fe(III) hydroxide, a typical Cr(III)-containing component in rCOPR, under visible light. At acidic conditions, the release rate of Cr(III) under illumination markedly increased, up to 7 times higher than that in the dark, yet no Cr(VI) was produced. While at basic conditions, only Cr(VI) was obtained by photo-oxidation, with an oxidation rate of ∼7 times higher than that by δ-MnO2 under dark conditions at pH 10, but no reactive oxygen species was generated. X-ray absorption near-edge structure and density functional theory analyses reveal that coexisting Fe in the solid plays a critical role in the pH-dependent release and transformation of Cr(III), where photogenerated Fe(II) accelerates Cr(III) produced at acidic conditions. Meanwhile, at basic conditions, the production of intermediate Cr(III)-Fe(III) clusters by light leads to the oxidation of Cr(III) into Cr(VI) through the nonradical "metal-to-metal charge transfer" mechanism. Our study provides a new insight into Cr(VI) reoccurrence in rCOPR and helps in predicting its environmental risk in nature.

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The structural, morphological, and optical properties of Ni2+ ions substitution in CoCr2O4 matrix as ceramic pigments were investigated. The thermal decomposition of the dried gel was performed aiming to understand the mass changes during annealing. The X-ray diffraction (XRD) studies reveal a spinel-type Face-Centered Cubic structure and a secondary Cr2O3 phase when x ≤ 0.75 and a Body-Centered Tetragonal structure when x = 1. Fourier Transform Infrared Spectroscopy (FT-IR) indicated two strong absorption bands corresponding to the metal-oxygen stretching from tetrahedral and octahedral sites, characteristic of spinel structure. Ultraviolet-Visible (UV-Vis) spectra exhibited the electronic transitions of the Cr2+ Cr3+ and Ni2+ ions. From the UV-Vis data, the CIE color coordinates, (x, y) of the pigments were evaluated. The morphology was examined by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) showing the agglomeration behavior of the particles. The stability, coloring properties and potential ceramic applications of studied pigments were tested by their incorporation in matte and glossy tile glazes followed by the application of obtained glazes on ceramic tiles. This study highlights the change in pigment color (from turquoise to a yellowish green) with Ni2+ ions substitution in the CoCr2O4 spinel matrix.

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For biotechnology applications, a novel nanobiocomposite was synthesized based on modification of graphene oxide (GO) by extracted silk fibroin (SF), natural polymer pectin (Pec) and zinc chromite (ZnCr2O4) nanoparticles (NPs). The structure and properties of hybrid nanobiocomposite GO-Pec/SF/ZnCr2O4 such as thermal stability, less toxicity, biocompatibility, antibacterial, and biodegradable were proved by using field emission scanning electron microscope (FE-SEM), Fourier-transformed infrared (FT-IR), Energy dispersive X-ray spectroscopy (EDS), thermal gravimetric analysis (TGA), and X-Ray diffraction (XRD). According to the biological features of substances, the GO-Pec/SF/ZnCr2O4 nanobiocomposite shows perfect results in MTT (83.71 %) and Hemolysis (16.52 %) assays. accordingly, mentioned properties of this nanobiocomposite can be used as a scaffold for medical applications.

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The alkali digestion pretreatment method in the United States Environmental Protection Agency (USEPA) Method 3060A could underestimate the content of Cr(VI) in Cr-contaminated soils, especially for soils mixed with chromite ore processing residue (COPR), which leads to a misjudgment of the Cr(VI) level in soils after remediation, causing secondary pollution to the environment. In this study, a new pretreatment method to analyze Cr(VI) concentration in contaminated soils was established. The impacts of soil quality, particle size, alkali digestion time and the rounds of alkali digestion on Cr(VI) detection in contaminated soils was explored and the alkali digestion method was optimized. Compared with USEPA Method 3060A, the alkaline digestion time was prolonged to 6 h and multiple alkali digestion was employed until the amount of Cr(VI) in the last extraction was less than 10% of the total amount of Cr(VI). Because Cr(VI) in COPR is usually embedded in the mineral phase structure, the hydration products were dissolved and Cr(VI) was released gradually during the alkaline digestion process. The amount of Cr(VI) detected showed high correlation coefficients with the percentage of F1 (mild acid-soluble fraction), F2 (reducible fraction) and F4 (residual fraction). The Cr(VI) contents detected by the new alkaline digestion method and USEPA Method 3060A showed significant differences for soil samples mixed with COPR due to their high percentage of residual fraction. This new pretreatment method could quantify more than 90% of Cr(VI) in Cr-contaminated soils, especially those mixed with COPR, which proved to be a promising method for Cr(VI) analysis in soils, before and after remediation.

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Antibiotic resistance is a global problem. This is the reason why scientists search for alternative treatments. In this regard, seven novel silver chromite nanocomposites were synthesized and assayed to evaluate their antimicrobial, antiviral, and cytotoxic activity. Five bacterial species were used in this study: three Gram-positive (Bacillus subtilis, Micrococcus luteus, and Staphylococcus aureus) and two Gram-negative (Escherichia coli and Salmonella enterica). Three fungal species were also tested: Candida albicans, Aspergillus niger, and A. flavus. The MIC of the tested compounds was determined using the bifold serial dilution method. The tested compounds showed good antibacterial activity. Maximum antibacterial activity was attained in the case of 15 N [Cobalt Ferrite (0.3 CoFe2O4) + Silver chromite (0.7 Ag0.5Cr2.5O4)] against M. luteus. Concerning antifungal activity, C. albicans was the most susceptible fungal species. The maximum inhibition was recorded also in case of 15 N [Cobalt Ferrite (0.3 CoFe2O4) + Silver chromite (0.7 Ag0.5Cr2.5O4)]. The most promising antimicrobial compound 15 N [Cobalt Ferrite (0.3 CoFe2O4) + Silver chromite (0.7 Ag0.5Cr2.5O4)] was assayed for its antiviral and cytotoxic activity. The tested compound showed weak antiviral activity. The cytotoxic activity against Mammalian cells from African Green Monkey Kidney (Vero) cells was detected. The inhibitory effect against Hepatocellular carcinoma cells was detected using a MTT assay. The antimicrobial effect of the tested compounds depends on the tested microbial species. The tested compounds could be attractive and alternative antibacterial compounds that open a new path in chemotherapy.

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Plant species sustaining under a polluted environment for a long time are considered as potentially resistant species. Those plant species can be considered as an eco-sustainable tool used to bio-monitor and mitigate pollution. This study was carried out on a total of ten commonly available plant species to assess their anticipated performance index (API), dust capturing capacity (DCC), and metal accumulation index (MAI) in chromite mine and control areas. According to the anticipated performance index (API), Macaranga peltata (Roxb.) Müll.Arg., Holarrhena pubescens Wall. ex G.Don and Ficus hispida Roxb. ex Wall. are highly tolerant species while Terminalia arjuna (Roxb. ex DC.) Wight & Arn. and Trema orientalis (L.) Blume are intermediate tolerant species. F. hispida was also shown to have the highest dust capturing capacity (5.94 ± 0.43 mg/cm2) whereas that of Woodfordia fruticosa Kurz (1.03 ± 0.11 mg/cm2) was found to be lowest. The metal accumulation index ranged from 17.29 to 4.5 and 6.38 to 1.94 at the mine and control areas, respectively. Two-way ANOVA analysis revealed area-wise significant differences between biochemical and physiological parameters. Also, results showed that the pollution level and heavy metal affected different biochemical and physiological parameters of plant species at the mining area. The plant species with the highest API, DCC, and MAI value could be recommended for greenbelt development in different polluted areas.

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