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Mycoremediation of Heavy Metals Contaminated Soil by Using Indigenous Metallotolerant Fungi

100%

Akram M. B. , Khan I. , Ur Rehman M. , Sarwar A. , Ullah N. , ur Rahman S. , Aziz T. , Alharbi M. , Alshammari A. , Alasmari A. F.

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2023

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tom Vol. 25, nr 3

1--13

EN

The present study was aimed to identify the indigenous fungal strains which could possibly be applied to the bioremediation of heavy metal-contaminated soil. The contaminated soil samples of Korangi Industrial Estate Karachi were found to have total concentration of Cu 1.044 mgL1 , and Pb 0.631 mgL–1. A total of eight indigenous strains of the fungus were isolated and screened for bioremediation capacity from heavy metals-contaminated soil. For the bioremediation of Lead (Pb) these same indigenous eight fungal strains were used for biological remediation. All the fungal isolated with enhanced bioremediation capability were through phenotypic and genotypical characterization. The topology of the phylograms established that the fungal isolates used in this study were allocated to: K1 (Penicillium notatum), K2 (Aspergillus parasiticus), K3 (Aspergillus fumigatus), K4 (Aspergillus flavus), K5 (Aspergillus terries), K6 (Fusarium solani), K7 (Penicillium chrysogenum), K8 (Aspergillus niger), K9 (Penicillium piceum) and K10 (Penicillium restrictum). Thus, K8 fungal isolate was found to be more efficient with maximum bioremediation capacity, for copper and lead removal efficiency, and selected for FTIR and SEM to find out the uptake of Cu and Pb which of the functional groups are involved, and further to detect the effects of bioleaching of both heavy metals on to the surface of K8 fungus biomass. The current study indicates that indigenous fungal isolates could be used with high potency to remediate or clean up the heavy metals-contaminated soil either by the technique of in situ or ex-situ bioremediation.

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Influences of operating parameters on dry ball mill performance

100%

Cayirli S.

Physicochemical Problems of Mineral Processing

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2018

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tom Vol. 54, iss. 3

751--762

EN

The paper is aimed to investigate the influence of operating parameters on dry fine grinding of calcite in a laboratory scale conventional ball mill. Within the context, the influence of operating parameters such as mill speed, ball filling ratio, ball size distribution, powder filling ratio, grinding aid dosage and grinding time were studied. The results of grinding tests were evaluated based on the product particle size (d50, d80) and surface area (m2/kg). As a result of this study, optimum grinding test conditions determined to be 70% of Nc, J=0.35 for ball filling ratio, 40 mm (10%), 32 mm (10%), 20 mm (40%), 12 mm (40%) for ball size distribution, fc=0.125 for powder filling ratio, 2000 g/Mg for grinding aid dosage and 60 min for grinding time. After determining optimum grinding conditions, the influence of grinding aid dosage on powder fluidity was determined. The use of 2000 g/Mg grinding aid dosage had a greater fluidizing effect compared to the other dosages and no aid condition (0 g/Mg). The influence of grinding aid on dry fine grinding of calcite was also examined by Fourier Transform Infrared Spectroscopy (FTIR). FTIR measurements indicated that grinding aid was adsorbed on the ground calcite particles surface.

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An Investigation of Microplastic Occurrence and Heavy Metals Concentrations in Street Dust on the Left Side of Mosul City, Iraq

84%

Almola M. A. , Al-Ahmady K. K. , Mhemid R. K. S.

Journal of Ecological Engineering

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2024

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tom Vol. 25, nr 9

116--132

EN

The issue of street dust pollution is primarily related to levels of microplastic particles (MPs) and heavy metals, raising concerns about their potential risk to the environment. In this work, twenty street dust samples with three replicates were collected from different areas (residential, commercial, and industrial) on the left side of Mosul city/Iraq, to investigate the presence of MPs and study their characteristics. Additionally, to assess the potential ecological risk impact of twelve heavy metals. Among the 60 dust samples taken from the streets, an average of MPs ranging between 244 and 2760 per 15 grams of dust was detected. Most of these plastic particles were transparent fragments with sizes varying from less than 10 to 200 µm as observed through a stereomicroscope and a scanning electron microscope (SEM). Furthermore, results from FTIR analysis indicated that polyvinyl chloride (PVC) was the dominant polymer type found in MPs, accounting for around 63%. The levels of metal in road dust were assessed using X-ray fluorescence (XRF) showing that quantification of Cr, Ni, Cu, Zn, As, Sb, Hg, and Pb surpassed the background values of world soils among the twelve elements studied. Variation coefficients (VCs) coupled with enrichment and contamination factors revealed that Cr, Cu, Zn, As, Se, Cd, Sb, Hg, and Pb are associated with both sources (anthropogenic and natural). On the other hand, Mn, Fe, and Ni originate from natural sources. Calculated potential ecological risk (Er) indicated high ecological risk by Hg. Approximately half of the samples exhibited moderate ecological risk indices (RI).

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Attaining Optimum Values of Colourfastness Properties of Sustainable Dyes on Cotton Fabrics

67%

Islam S. , Alam S. M. M. , Ahmed S.

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2020

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tom Vol. 28, no. 6 (144)

110--117

EN

The aim of this research was to identify optimum values of the colorfastness properties of sustainable dyes on cotton fabrics. Sustainable dyes are ecofriendly, biodegradable, economical and easily attainable from natural sources. The findings of this research established that good colourfastness properties of cellulosic fibres could be obtained using sustainable natural dyes. Experiments were carried out on 100% cotton voile fabrics of plain weave using four types of natural dyes: strawberry dye, beetroot dye, rose dye and China rose dye. Strawberry dye reacted with the cellulose of the cotton in an alkaline condition to form a stable covalent bond amid the dye and cellulose and showed outstanding colour fastness properties. The required experiments were conducted using the standard specified by ASTM and AATCC as stated in this paper. The colour strength properties, colour intensity properties, colour absorbency properties and colorfastness properties were investigated using a reflectance spectrophotometer and “Agilent Cary 630 FTIR Instrument” as stated in this paper. A sample dyeing machine – “Pad Dye Pad Steam” was used in this research to dye the cotton fabrics with sustainable natural dyes. The colorfastness properties were investigated using grey scale test results, and the colour strength and absorbency properties were tested using the spectrophotometer and FTIR instruments. The peak values of the FTIR instrument guaranteed the existence of the colourant or chromophore present in the dyestuffs, and exposed the best colourfastness properties. The findings of this research could be beneficial to personnel involved in textile industries who are in charge of dyeing cotton fabrics with natural dyes as well as controlling their colourfastness properties and colour intensity properties.

PL

Celem badań było określenie optymalnych wartości właściwości trwałości koloru barwników naturalnych na tkaninach bawełnianych. Naturalne barwniki są przyjazne dla środowiska, biodegradowalne, ekonomiczne i łatwo dostępne z naturalnych źródeł. Wyniki tych badań wykazały, że dobre właściwości trwałości koloru włókien celulozowych można uzyskać przy użyciu trwałych naturalnych barwników. Eksperymenty przeprowadzono na tkaninach woalowych w 100% bawełnianych o splocie płóciennym przy użyciu czterech rodzajów barwników naturalnych: barwnika truskawkowego, buraczkowego, różowego i chińskiego różowego. Barwnik truskawkowy przereagował z celulozą bawełny w środowisku zasadowym, tworząc stabilne wiązanie kowalencyjne między barwnikiem i celulozą i wykazał wyjątkową trwałość koloru. Wymagane eksperymenty przeprowadzono przy użyciu standardu określonego przez ASTM i AATCC. Właściwości trwałości koloru zbadano za pomocą wyników testu w skali szarości, a siłę koloru i właściwości absorpcyjne zbadano za pomocą spektrofotometrii w podczerwieni (FTIR).