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The paper describes the issues associated with waste generated during steel production and processing, in particular the dust from electric arc furnaces (EAF). An effective solution for the disposal of such waste is its involvement in processing to obtain valuable products. This paper studies the physical and chemical properties of EAF dust produced during the smelting of metallized pellets and captured by the dust and gas cleaning system of the steel-smelting shop at the Oskol Electrometallurgical Combine, Belgorod Region. The results obtained in the study of the chemical and disperse compositions of dust, the microstructure of the surface made it possible to propose the use of dust as a raw material for coagulant production. The conditions of acid-thermal treatment of dust are determined, contributing to the partial dissolution of iron (II), (III), and aluminium compounds, which ensure the coagulation processes during wastewater treatment. Model solutions show high efficiency (> 95 %) of water treatment from heavy metal ions by modified EAF dust.

We present a learning concept treating the detection, intake and possible effects of aluminium ions. It was tested in grade 10 of a grammar school (Gymnasium). On the one hand biological and chemical topics are closely connected, on the other hand an insight into research is given. [ABSTRACT FROM AUTHOR]

Summary: Previous work showed that the bioavailability of fluoride in dark tea was lower than NaF solution. However, limited information is available indicating the effects of tea components on the fluoride bioavailability. In this study, the effects of the components in tea on the bioavailability of fluoride were evaluated in the Caco‐2 cell line model. Additionally, the mechanism of effect of aluminium on fluoride transport was investigated. The result showed that 10–100 μm of epigallocatechin gallate (EGCG) could not influence fluoride transport. Al3+ significantly decreased fluoride transport in both apical‐basolateral and basolateral‐apical directions. Moreover, aluminium could form different forms of aluminium fluoride complexes, which were transported through Caco‐2 cells by different pathways. F− transport was mainly dependent on the paracellular pathway and active transport involving Cl− channels. The paracellular pathway played a predominant role in transport of AlF3. The paracellular pathway and active transport both participated in AlF2+ transport. [ABSTRACT FROM AUTHOR]

The effects of Pb(II) ions and Al(III) ions on the electro kinetic and flotation behavior of rutile were investigated by micro-flotation tests, zeta potential measurements and solution chemistry analysis. Micro-flotation results indicate that the Pb(II) ions can effectively improve the flotation recovery of rutile while the Al(III) ions significantly inhibit the flotation of rutile. Zeta potential measurements reveal that a collector styrene phosphoric acid (SPA) can adsorb on the rutile surface after the addition of Pb(II) ions, but hardly adsorb on the rutile surface after the addition of Al(III) ions. Pb(II) ions adsorb on the rutile surface in the form of Pb(OH)+ and Pb(OH)2(s), and the latter one is the main reason that activates rutile flotation. Al(III) ions adsorb on the rutile surface mainly in the form of Al(OH)3(s), which prevent the direct interaction between the rutile and the collector, resulting in a decrease of rutile flotation recovery. [ABSTRACT FROM AUTHOR]

Abstract The study investigates the role of the electrostatic interactions in the fibrillation of the hen egg white lysozyme (HEWL). In order to achieve this aim the influence of the cations Na+, Mg2+ and Al3+ on the amyloid fibril formation and amorphous aggregation was tested. The amyloids are formed in the solution without added salt but the Thioflavin T fluorescence gives the false-negative result. In these conditions, the HEWL fibrils are long and curvy. If the ionic strength of the solution is sufficiently high, the formed amyloids are shorter and fragmented. Our study shows that the addition of the aluminium salt promotes protein fibrillation. The amorphous aggregation dominates in the high concentration of electrolyte. The in vitro amyloid fibril formation seems to be regulated by universal mechanisms. The theories implemented in the polymer science or for colloidal solutions give the qualitative description of the aggregation phenomena. However, the specific interactions and the additional effects (e.g. fibril fragmentation) modulate the amyloidogenesis. Highlights • Influence of cations on lysozyme fibrillation/amorphous aggregation was tested. • In low concentration of salt, ThT is negative but amyloids are present. • In high concentration of salt, amorphous aggregation dominates. • Aluminium ions promote amyloid fibril formation. [ABSTRACT FROM AUTHOR]

A Petridish and hydroponic culture experiments were conducted at Crop Physiology Laboratory, Department of Crop Botany and Agriculture Chemistry Laboratory, Bangladesh Agricultural University, Mymensingh during the period from August to October 2011 to investigate the effect of aluminium on morphological characters and growth of wheat seedlings. The experiment comprised of two levels of aluminium concentrations viz., 0 µM (control) and 100 µM and five varieties viz; Kanchan, Shatabdi, Sourav, Bijoy (BARI-23) and Sufi (BARI-22). The experiment was laid out in two factors completely randomized design with three replications. Applications of 100 µM aluminium had a profound influence on hypocotyls and epicotyls length, germination percentages, and root-shoot length, fresh and dry mass production in wheat. Results indicated that germination percentage, hypocotyls and epicotyls length, root and shoot length, leaf length, leaf sheath length, plant height, fresh and dry mass plant were greater in control than aluminium stress conditions. It revealed that wheat seedlings are susceptible to aluminium stress. However, among the varieties, the reduction of dry mass under aluminium stress was minimum in Shatabdi followed by Kanchan showed that Shatabdi was more tolerant to aluminium stress than the other varieties namely Sourav, Bijoy (BARI-23) and Sufi (BARI-22). Sufi and Sourav were more susceptible to aluminium stress. [ABSTRACT FROM AUTHOR]

Aluminium (Al) is clearly neurotoxic and considerable evidence exists that Al may play a role in the aetiology or pathogenesis of Alzheimer’s disease (AD). Nevertheless, the link between AD pathology and Al is still open to debate. Therefore, we investigated here the interaction of aluminium ions with two Aβ peptide fragments and their analogues. First, we synthesised by the Fmoc/tBu solid-phase peptide synthesis (SPPS) strategy using an automated peptide synthesiser two new peptides starting from the Aβ(1–16) native peptide fragment. For this purpose, the three histidine residues (H6, H13, and H14) of the Aβ(1–16) peptide were replaced by three alanine and three serine residues to form the modified peptides Aβ(1–16)A36,13,14 and Aβ(1–16)S36,13,14 (primary structures: H-1DAEFRADSGYEVAAQK16-NH2 and H-1DAEFRSDSGYEVSSQK16-NH2). In addition, the Aβ(9–16) peptide fragment (H-9GYEVHHQK16-NH2) and its glycine analogues, namely Aβ(9–16)G110, (H-9GGEVHHQK16-NH2), Aβ(9–16)G213,14 (H-9GYEVGGQK16-NH2), and Aβ(9–16)G310,13,14 (H-9GGEVGGQK16-NH2), were manually synthesised in order to study Al binding to more specific amino acid residues. Both the peptides and the corresponding complexes with aluminium were comparatively investigated by mass spectrometry (MS), circular dichroism spectroscopy (CD), atomic force microscopy (AFM), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FT-IR). Al–peptide molecular ions and Al-fragment ions were unambiguously identified in the MS and MS/MS spectra. AFM images showed dramatic changes in the film morphology of peptides upon Al binding. Our findings from the investigation of N-terminal 1-16 and even 9-16 normal and modified sequences of Aβ peptides suggest that they have the capability to be involved in aluminium ion binding associated with AD.

Chondroitin sulphate is a sulphated glycosaminoglycan biopolymer composed over 100 individual sugars. Chondroitin sulphate nanoparticles (NPs) loaded with catechin were prepared by an ionic gelation method using AlCl3 and optimised for polymer and cross‐linking agent concentration, curing time and stirring speed. Zeta potential, particle size, loading efficiency, and release efficiency over 24 h (RE24 %) were evaluated. The surface morphology of NPs was investigated by scanning electron microscopy and their thermal behaviour by differential scanning calorimetric. Antioxidant effect of NPs was determined by chelating activity of iron ions. The cell viability of mesenchymal stem cells was determined by 3‐[4, 5‐dimethylthiazol‐2‐yl]‐2, 5‐diphenyl tetrazolium bromide assay and the calcification of osteoblasts was studied by Alizarin red staining. The optimised NPs showed particle size of 176 nm, zeta potential of −20.8 mV, loading efficiency of 93.3% and RE24 % of 80.6%. The chatechin loaded chondroitin sulphate NPs showed 70‐fold more antioxidant activity, 3‐fold proliferation effect and higher calcium precipitation in osteoblasts than free catechin. [ABSTRACT FROM AUTHOR]

A simple and efficient method for the fabrication of highly fluorescent chitosan/silver (CS/Ag) films is reported in this paper. The synthesis method uses NaBH4as a reductant and involves less time and extremely mild experimental conditions. The structure, surface and fluorescence properties of the nano-sized CS/Ag films were investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry and scanning electron microscopy. Aluminium ion sensing was determined by and fluorescence intensity measurement. Fluorescence measurement by emission spectroscopy indicated that the emission wavelength of CS/Ag was 368 nm. Experimental results indicated that the fluorescence emission of the nanocomposite films was sensitive to the presence of aluminium ions, and a micro-amount of aluminium ions significantly increases the emissions. Under the optimum conditions, the fluorescence intensity of the films was linearly proportional to aluminium ion concentrations between 0 and 1·8 × 10−4 mol L−1. The films may be developed into sensors for aluminium ions. [ABSTRACT FROM PUBLISHER]

Fluorescent chemodosimeters based on small organic molecules are widely used in the detection of various analytes. However, chemodosimeters for metal ion detection are still limited to a few transition metals, such as HgII, CuII, FeIII, AuIII, etc. In this work, a fluorescent chemodosimeter of 5-chloro-7-phenyliminomethyl-8-hydroxyquinoline ( 2) for the detection of AlIII is reported. Chemodosimeter 2 exhibits a turn-on fluorescence response to AlIII owing to an AlIII-promoted hydrolysis of carbon-nitrogen double bonds. This reaction yielded a 1- Al complex, which exhibited high fluorescence emission at 487 nm based on inhibition of excited-state intramolecular proton transfer (ESIPT). Because of the specific catalytic ability of AlIII, the selectivity of 2 to AlIII is excellent both in aqueous solutions and in solid matrix. The fluorescence enhancement was as high as 582-fold and the turn-on fluorescence can be observed even by the naked eye upon an irradiation with a UV lamp. The detection limit of 2 for AlIII sensing is 54 nmol L−1 and the linear range is 0-50 μmol L−1. This work provides a new strategy for designing main-group-metal chemodosimeters based on small organic molecules. [ABSTRACT FROM AUTHOR]

The work was targeted on the study of egg white foam forming, including the influence of pH, aluminium ions, xanthan, maltodextrin, and phosphates on the whipping and stability of egg white foams. The whipping was studied with non pasteurised and pasteurised egg white using the blender with planet motion. Both types of egg white formed good foam in the acid area (pH below 4.5) and at neutral pH. Aluminium ions had a positive effect on the foam volume and stability, especially with the non pasteurised egg white. The addition of maltodextrin or saccharose decreased the foam volume but increased the foam stability. The addition of natrium pyrophosphate or natrium hexametaphosphate had a positive effect on the volume, density, and stability of foam. Foams with hexametaphosphate were applied into confectionary products.

A chemosensor based on pyridoxal hydrazone was prepared in a two-step synthesis with a high yield. Chemosensor 1 exhibits high sensitivity and anti-disturbance for aluminium(III) ions among other biologically important metal ions. Aluminium(III) ion sensing was accomplished using a chelation enhanced fluorescence (CHEF) effect and photoinduced electron transfer (PET) inhibition. Chemosensor 1 shows a high association constant (1×10 5 M −1 ) towards aluminium(III) ions in DMSO-H 2 O (9:1, v/v). The detection limit of the fluorescence response of chemosensor 1 for aluminium(III) ions is 6×10 −7 M. [ABSTRACT FROM AUTHOR]