232 research outputs found

    An overview of zeolites synthesised from coal fly ash and their potential for extracting heavy metals from industrial wastewater

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    Zeolites are aluminosilicate minerals widely used in industrial applications including as commercial adsorbents and catalysts. This overview focuses on zeolites synthesised from coal fly ash (CFA). Human activities and industrial developments generate large volumes of polluted water, which have a significant ecological impact. Industrial wastewater may consist of different pollutant types, but of specific interest to this work are heavy metals, which. Heavy metal ions are among the most dangerous pollutants due to their toxicity and carcinogenicity. This overview covers the recent scientific literature, focused on using CFA-derived zeolites to remove Ni, Hg, Mn, Cu, Zn, Cd, Pb, Cr, Co both from synthetic solutions replicating industrial wastewater and actual wastewater streams. The results described in many papers cited in this review look promising for industrial wastewater treatment operations. Furthermore, the large variety of possible synthetic zeolites provides a route for energy-efficient, pollutant-specific remediation of industrial heavy metals

    Magnetic Zeolite:Synthesis and Copper Adsorption Followed by Magnetic Separation from Treated Water

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    Zeolites are widely used in diverse applications, including the removal of heavy metals from wastewater. However, separating fine-sized zeolite particles from treated water is often a challenge. In this work, a novel method utilizing a colloidal polyvinyl alcohol (PVA) solution to bind iron oxide nanoparticles to a Linde Type A (LTA) zeolite was used to synthesize magnetic zeolite. Different zeolite–iron oxide nanoparticle loadings (10:1, 10:0.5, and 10:0.1) were used in batch adsorption experiments to investigate adsorption capacities and kinetics for Cu removal from an aqueous solution. The results showed that the magnetic zeolite maintained much of its adsorbent properties while facilitating a simplified process design. Thus, the adsorption capacity of pure LTA zeolite was found to be 262 mg/g for magnetic zeolite, with a 10:1 ratio—151 mg/g; 10:0.5—154 mg/g; and 10:0.1—170 mg/g. Magnetic separation was subsequently employed to remove the magnetic zeolite from the treated solution

    Copper ion removal from dilute solutions using ultrasonically synthesised BSA- and EWP-coated air bubbles

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    The aim of this study was to remove copper ions from dilute copper solution using an innovative material known as air-filled emulsion (AFE). AFE is composed of microscopic bubbles enclosed by a thin film of cysteine-rich protein distributed through the aqueous solution. The method using AFE as an extractant is combination of air-assisted solvent extraction (AASX) and biosorption techniques. The data obtained from X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) clearly showed the thiol, amino and carboxylic groups of bovine serum albumin (BSA) and egg white protein (EWP)-coated bubbles being responsible for copper adsorption. Moreover, it was also observed that manipulation of experimental conditions such as solution pH, temperature, biosorbent and copper concentration had a significant impact on copper ion uptake. Higher solution pH led to a greater metal uptake for both egg white protein emulsion (EWPEM) and bovine serum albumin emulsion (BSAEM). At lower pH, copper removal diminished and no copper removal was obtained at pH 2 due to the high concentration of hydrogen ions. The increase of copper uptake with temperature rise was due to both the exposure of more functional groups that were initially buried in the interior of the protein structure and an increase in reaction kinetics

    Materials characterization of advanced fillers for composites engineering applications

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    Four different minerals were investigated; hollow spheres of calcium carbonate, platy mica, needle like wollastonite and glassy perlite and characterized via iGC for surface energy, Freeman powder rheology for flow characterization, cyclic uniaxial die compaction for modulus of elasticity and frequency dependent sound absorption properties. Particle surface energy and particle shape strongly affected the packing density of powder beds. In the case of higher porosity and thus lower bulk density, the powders acoustic absorption was higher in comparison with higher packing density materials. Surface energy profiles and surface energy distributions revealed clear convergence with powder rheology data, where the character of the powder flow at defined consolidation stresses was mirroring either the high cohesion powders properties connected with the high surface energy or powder free flowing characteristics, as reflected in low cohesion of the powder matrix.Ministry of Industry and Trade of the Czech Republic [OP PIK CZ.01.1.02/0.0/0.0/16_084/0010256

    Nanoporous sponges as carbon-based sorbents for atmospheric water generation

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    Water scarcity threatens more and more people in the world. Moisture adsorption from the atmosphere represents a promising avenue to provide fresh water. Nanoporous sponges (“NPSs” ), new carbon-based sorbents synthesized from the pyrolysis of resorcinol-formaldehyde resin, can achieve comparable performance to metal organic framework-based systems, but at a significantly lower cost. Oxygen and nitrogen functionalities can be added to the NPS surface, through oxidation and addition of phenanthroline to the initial reagent mixture, respectively. The resulting NPS sorbents have high specific surface areas of 347 to 527 m2·g–1 and an average capillary-condensation-compatible pore size of 1.5 nm. When oxidized, the NPS can capture up to 0.28 g of water per gram of adsorbent at a relative pressure of 0.90 (0.14 g·g–1 at P/Psat = 0.40) and maintain this adsorption capacity over multiple adsorption/desorption cycles. Scaled-up synthesis of the NPS was performed and tested in an experimental water capture setup, showing good agreement between small- and larger-scale adsorption properties. Water adsorption isotherms fitted with the theoretical model proposed by Do and Do demonstrate that hydroxyl functionalities are of key importance to NPS behavior

    Advances in Microbial Biofilm Prevention on Indwelling Medical Devices with Emphasis on Usage of Acoustic Energy

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    Microbial biofilms are a major impediment to the use of indwelling medical devices, generating device-related infections with high morbidity and mortality. Major efforts directed towards preventing and eradicating the biofilm problem face difficulties because biofilms protect themselves very effectively by producing a polysaccharide coating, reducing biofilm sensitivity to antimicrobial agents. Techniques applied to combating biofilms have been primarily chemical. These have met with partial and limited success rates, leading to current trends of eradicating biofilms through physico-mechanical strategies. Here we review the different approaches that have been developed to control biofilm formation and removal, focusing on the utilization of acoustic energy to achieve these objectives

    Loss-of-function mutations in SLC30A8 protect against type 2 diabetes.

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    Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/OpenLoss-of-function mutations protective against human disease provide in vivo validation of therapeutic targets, but none have yet been described for type 2 diabetes (T2D). Through sequencing or genotyping of ~150,000 individuals across 5 ancestry groups, we identified 12 rare protein-truncating variants in SLC30A8, which encodes an islet zinc transporter (ZnT8) and harbors a common variant (p.Trp325Arg) associated with T2D risk and glucose and proinsulin levels. Collectively, carriers of protein-truncating variants had 65% reduced T2D risk (P = 1.7 × 10(-6)), and non-diabetic Icelandic carriers of a frameshift variant (p.Lys34Serfs*50) demonstrated reduced glucose levels (-0.17 s.d., P = 4.6 × 10(-4)). The two most common protein-truncating variants (p.Arg138* and p.Lys34Serfs*50) individually associate with T2D protection and encode unstable ZnT8 proteins. Previous functional study of SLC30A8 suggested that reduced zinc transport increases T2D risk, and phenotypic heterogeneity was observed in mouse Slc30a8 knockouts. In contrast, loss-of-function mutations in humans provide strong evidence that SLC30A8 haploinsufficiency protects against T2D, suggesting ZnT8 inhibition as a therapeutic strategy in T2D prevention.US National Institutes of Health (NIH) Training 5-T32-GM007748-33 Doris Duke Charitable Foundation 2006087 Fulbright Diabetes UK Fellowship BDA 11/0004348 Broad Institute from Pfizer, Inc. NIH U01 DK085501 U01 DK085524 U01 DK085545 U01 DK085584 Swedish Research Council Dnr 521-2010-3490 Dnr 349-2006-237 European Research Council (ERC) GENETARGET T2D GA269045 ENGAGE 2007-201413 CEED3 2008-223211 Sigrid Juselius Foundation Folkh lsan Research Foundation ERC AdG 293574 Research Council of Norway 197064/V50 KG Jebsen Foundation University of Bergen Western Norway Health Authority Lundbeck Foundation Novo Nordisk Foundation Wellcome Trust WT098017 WT064890 WT090532 WT090367 WT098381 Uppsala University Swedish Research Council and the Swedish Heart- Lung Foundation Academy of Finland 124243 102318 123885 139635 Finnish Heart Foundation Finnish Diabetes Foundation, Tekes 1510/31/06 Commission of the European Community HEALTH-F2-2007-201681 Ministry of Education and Culture of Finland European Commission Framework Programme 6 Integrated Project LSHM-CT-2004-005272 City of Kuopio and Social Insurance Institution of Finland Finnish Foundation for Cardiovascular Disease NIH/NIDDK U01-DK085545 National Heart, Lung, and Blood Institute (NHLBI) National Institute on Minority Health and Health Disparities N01 HC-95170 N01 HC-95171 N01 HC-95172 European Union Seventh Framework Programme, DIAPREPP Swedish Child Diabetes Foundation (Barndiabetesfonden) 5U01DK085526 DK088389 U54HG003067 R01DK072193 R01DK062370 Z01HG000024info:eu-repo/grantAgreement/EC/FP7/20201
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