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The oxidation of chromium in air at 700 °C was investigated with a focus on point defect behavior and transport during oxide layer growth. A comprehensive set of characterization techniques targeted characteristics of chromium oxide microstructure and chemical composition analysis. TEM showed that the oxide was thicker with longer oxidation times and that, for the thicker oxides, voids formed at the metal/oxide interface. PAS revealed that the longer the oxidation time, there was an overall reduction in vacancy-type defects, though chromium monovacancies were not found in either case. EIS found that the longer oxidized material was more electrochemically stable and that, while all oxides displayed p-type character, the thicker oxide had an overall lower charge carrier density. Together, the results suggest anion oxygen interstitials and chromium vacancy cluster complexes drive transport in an oxidizing environment at this temperature, providing invaluable insight into the mechanisms that regulate corrosion.

The oxidation of chromium in air at 700 °C was investigated with a focus on point defect behavior and transport during oxide layer growth. A comprehensive set of characterization techniques targeted characteristics of chromium oxide microstructure and chemical composition analysis. TEM showed that the oxide was thicker with longer oxidation times and that, for the thicker oxides, voids formed at the metal/oxide interface. PAS revealed that the longer the oxidation time, there was an overall reduction in vacancy-type defects, though chromium monovacancies were not found in either case. EIS found that the longer oxidized material was more electrochemically stable and that, while all oxides displayed p-type character, the thicker oxide had an overall lower charge carrier density. Together, the results suggest anion oxygen interstitials and chromium vacancy cluster complexes drive transport in an oxidizing environment at this temperature, providing invaluable insight into the mechanisms that regulate corrosion. [ABSTRACT FROM AUTHOR]

Corrosion processes are often discussed as stochastic events. Here, it is shown that some of these seemingly random processes are not driven by nanoscopic fluctuations but rather by the spatial distribution of micrometer-scale heterogeneities that trigger fast reactions associated with corrosion. Using a novel excitable reaction-diffusion model, corrosion waves traveling over the metal surface and the associated material loss are described. This resulting nonuniform corrosion penetration, seen as a height loss in modeling, exposes buried intermetallic particles, which depending on the local electrochemical state of the surface trigger or block new waves. Informed by quantitative experimental data for the Mg-Al-Zn alloy AZ31B, wave speeds, wave widths, and average material loss are accurately captured. Morphogenic mitigation based on wave-breaking microparticles is also simulated. While AZ31B corrosion is identified as a process driven by rare-wave events, this study predicts several other corrosion regimes that proceed via spots or patchy patterns, opening the door for new protection, design, and prediction strategies., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

The article presents the possibility of increasing the water resistance of gypsum binders (GBs) obtained based on synthetic gypsum by introducing additives derived from industrial wastes. Regularities were obtained for the influence of the type and amount of additives on the water/gypsum ratio (W/G), strength indicators and water resistance of high-strength GB. The introduction of a single-component additive to improve water resistance does not have a significant effect. Complex additives based on Portland cement, granulated blast-furnace slag, electric steel-smelting slag, expanded clay dust and granite screenings of various fractions have been developed that make the maximum contribution to improving the water resistance of a high-strength GB based on synthetic calcium sulphate dihydrate, which made it possible to increase the water-resistance coefficient from 0.39 to 0.82., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Implementation of nanotechnology in agriculture is of interest primarily to improve the growth and productivity of crops, and to minimize the use of traditional expensive chemical fertilizers. This work presents a simple energy-conservative approach for the synthesis of CoCuFeNi high entropy alloy nanoparticles (HEA-NPs) capable of forming a stable suspension with a concentration of 0.3 g/L. The size, composition, and morphology of the nanoparticles were analyzed by XRD, SEM, TEM, and EDS. Obtained HEA-NPs were characterized by fine crystallinity with an average size of 25 nm. The investigated suspensions of HEA-NPs were tested for seeds germination and plants growth. The use of suspension of CoCuFeNi HEA-NPs for plant irrigating together with ordinary water showed positive results in plant biostimulation, which resulted in the plant height up to 12% for watercress and up to 50% for oil radish. CoCuFeNi HEA-NPs showed nice inactivation activity for Pseudomonas aeruginosa that was comparable for the use of Tetracycline., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Gold (Au) nanoparticles (NPs) are widely used in nanomedical applications as a carrier for molecules designed for different functionalities. Previous findings suggested that biological molecules, including amino acids, could contribute to the dissolution of Au NPs in physiological environments and that this phenomenon was size-dependent. We, therefore, investigated the interactions of L-cysteine with 5-nm Au NPs by means of time-of-flight secondary ion mass spectrometry (ToF-SIMS). This was achieved by loading Au NPs on a clean aluminum (Al) foil and immersing it in an aqueous solution containing L-cysteine. Upon rinsing off the excessive cysteine molecules, ToF-SIMS confirmed the formation of gold cysteine thiolate via the detection of not only the Au-S bond but also the hydrogenated gold cysteine thiolate molecular ion. The presence of NaCl or a 2-(N-morpholino)ethanesulfonic acid buffer disabled the detection of Au NPs on the Al foil. The detection of larger (50-nm) Au NPs was possible but resulted in weaker cysteine and gold signals, and no detected gold cysteine thiolate signals. Nano-gold specific adsorption of L-cysteine was also demonstrated by cyclic voltammetry using paraffine-impregnated graphite electrodes with deposited Au NPs. We demonstrate that the superior chemical selectivity and surface sensitivity of ToF-SIMS, via detection of elemental and molecular species, provide a unique ability to identify the adsorption of cysteine and formation of gold-cysteine bonds on Au NPs.

Successful water treatment is one of the most important aspects for a healthy human life and environmental protection. This study deals with the investigation of a modified catalytic material that is used in water treatment as one of the most promising filter media for water deironing. The activated carbon granules were coated with iron oxide by solution combustion synthesis (SCS) method in a muffle furnace oven. We investigated obtained samples using different diffraction and spectroscopic methods. The elemental composition of the surface and phases of produced materials and the results of comparative analysis with initial samples of the raw material used for the underground water deironing were presented. Using the SCS method, active coal granules were modified with a formation of fine dispersed and crystalline structures of magnetite on their surface. This had a positive effect on the catalytic capacity of the material for deironing of underground water as well as for the specific surface area increase. The residual concentration of total iron in the first portions of the filtrate when using modified samples was almost 3 times lower than for initial material., Competing Interests: Declaration of competing interest Authors declare no competing interests., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Aim of this study was to assess qualitative and quantitative features of deformation parameters of left ventricular myocardium in patients with ischemic heart disease (IHD) with and without history of myocardial infarction (MI) using two-dimensional strain imaging. We examined 30 patients with clinical IHD with (group 1, n = 15) and without (group 2, n = 15) history of MI and 20 healthy volunteers. Compared with healthy subjects IHD patients of both groups had reduced longitudinal and circular myocardial deformation. There were no significant differences between patients with IHD and controls in parameters of radial, global, and regional deformation.

Two DNase I-hypersensitive regions are identified on the regulatory region of the rat tryptophan dioxygenase (tdo) gene which is expressed tissue-specifically under control ofglucocorticoid hormones. DNase I-hypersensitive regions are identified in position -470 and in the vicinity of the first upstream gene. Micrococcal nuclease digestion pattern of this region shows disturbances in the regular cleavage and appearance of shorter DNA molecules than nucleosomal DNA. However the control experiments demonstrate that the same DNA region could be involved in the regular nucleosome core particles under in vitro reconstitution. Taken together, these data show that the nucleosome array in the regulatory region of the actively transcribed tdo gene in vivo is disturbed.

Inducible hormone-dependent tryptophan oxygenase gene is expressed mostly in the liver under the control of glucocorticoid hormones. In the regulatory region of this gene there are three constitutive sites independent of hormone presence and gene expression. While investigating transcription factors responsible for the formation of specific chromatin structure in the regulatory region of inducible genes it is necessary to identify proteins which can bind to DNA specifically in these sites. The present paper reports investigation of transcription factors which bind to DNA from the -292nd to the -178th nucleotide of gene to in vitro. This DNA region contains a site corresponding to the constitutive DNase I hypersensitive site in vivo. Using electrophoretic mobility shift assay, we have analysed binding of rat liver proteins to this DNA region. NF1-rich nuclear protein fraction was purified from the rat liver nuclear extract by DEAE-cellulose and heparin-sepharose chromatography. Studies of the competition with a consensus sequence site for NF1 recognition sites have shown that it is the NF1 family transcription factors that are responsible for the formation of these specific complexes.

Using electrophoretic mobility shift assay we have analysed the binding of rat liver nuclear proteins to the fragments from -466 to -292 and from -292 to -178 relative to the transcriptional start site of the rat tryptophan oxygenase gene. Studies of the competition with a synthetic consensus sequence for the NF 1 recognition site have shown that the liver nuclear proteins, responsible for the formation of specific complexes with these fragments belong to the family of the nuclear factor 1 (NF 1). We have also found that the trans-acting factors of the NF 1 family form several complexes with each of the two tested fragments of the tryptophan oxygenase gene.

We have examined DNase I hypersensitive sites in the 5'-flanking region of the rat tryptophan oxygenase gene in recombinant plasmids. We have found two DNase I-hypersensitive sites in regions that map between -350 to -210 and -180 to -90 bp from the cap site. Both hypersensitive sites are found in supercoiled plasmids but not in linear or relaxed DNA molecules. The position of the hypersensitive sites of the 5'-flanking sequence of the rat tryptophan oxygenase gene in recombinant plasmids correlate with the chromatin sites first determined by Becker et al. The hypersensitive regions in the recombinant plasmids include the DNase I-hypersensitive sites in chromatin but extend somewhat upstream and downstream from these. Computer analysis of the 5'-flanking DNA region of the gene suggests that the DNA fragment spanning nucleotides -231 to -207 forms a potential hairpin loop with 15 unpaired bases. Chromatin reconstitution with histones on supercoiled plasmids carrying the 5'-flanking region of the rat tryptophan oxygenase gene suppresses both in vitro DNase I-hypersensitive sites. We have also shown that the DNA region containing the supercoil-dependent DNase I-hypersensitive site in the position between -350 and -210 bp from the cap site may form nucleosomes after reconstitution with histones.

In patients with toxic infections salmonellae were identified in 31% of cases. The patients were divided into two groups: the control group receiving treatment with infusion solutions and the test group treated, in addition to the usual scheme of therapy, with indomethacin in a daily dose of 150 mg. The study revealed that salmonellae isolated at the initial stages of the disease possessed highly pronounced adhesive properties. The adhesive properties of salmonellae isolated at the stage of convalescence from the patients of the test group were considerably less pronounced than those of salmonellae isolated from the same patients at the peak of the disease. In the control group no differences in the adhesive properties of salmonellae isolated from the same patients were established.