•Long-term forecasts of corrosion mass losses of metals in atmosphere are presented.•Three models for the long-term forecast are given.•The forecasts are given for test locations within the ISO ...CORRAG program.•A comparative estimate of the forecasts is given.
An analysis of the results of corrosion tests on flat and helix specimens made of technically important metals carried out within the ISO CORRAG program is given. Stochastic relationships between coefficient n in the power function, which characterizes the protective properties of the corrosion products, and the limiting corrosion rate α, with the corrosivity of each type of atmosphere were found. A forecast of corrosion losses for a period of up to 50years was given using the linear function in the stationary stage, a power function, and limiting corrosion rate values α. The reliability of the forecasts was estimated.
•Long-term predictions of corrosion mass losses of metals in atmosphere are presented.•Conditions for application of the power and power-linear functions are shown.•The functions are estimated in ...comparison with the models in ISO CORRAG standard.
A technique for calculation of coefficients in the power-linear function for long-term prediction of corrosion losses of structural metals is presented. The formula consists of a power function at the initial corrosion stage and a linear function at the stationary stage. Conditions for application of the power and power-linear functions for long-term prediction of corrosion losses of technically important metals in various regions of the world are shown. A comparative estimate of predicted corrosion losses of metals based on the equations provided in this study and in ISO CORRAG 9224:2012(E) standard is given.
The ability of model animal species, such as Drosophila melanogaster, to adapt quickly to various adverse conditions has been shown in many experimental evolution studies. It is usually assumed by ...default that such adaptation is due to changes in the gene pool of the studied population of macroorganisms. At the same time, it is known that microbiome can influence biological processes in macroorganisms. In order to assess the possible impact of microbiome on adaptation, we performed an evolutionary experiment in which some D. melanogaster lines were reared on a food substrate with high NaCl concentration while the others were reared on the standard (favourable) substrate. We evaluated the reproductive efficiency of experimental lines on the high salt substrate three years after the experiment started. Our tests confirmed that the lines reared on the salty substrate became more tolerant to high NaCl concentration. Moreover, we found that pre-inoculation of the high salt medium with homogenized salt-tolerant flies tended to improve reproductive efficiency of naïve flies on this medium (compared to pre-inoculation with homogenized control flies). The analysis of yeast microbiome in fly homogenates revealed significant differences in number and species richness of yeasts between salt-tolerant and control lines. We also found that some individual yeast lines extracted from the salt-tolerant flies improved reproductive efficiency of naïve flies on salty substrate (compared to baker's yeast and no yeast controls), whereas the effect of the yeast lines extracted from the control flies tended to be smaller. The yeast Starmerella bacillaris extracted from the salt-tolerant flies showed the strongest positive effect. This yeast is abundant in all salt-tolerant lines, and very rare or absent in all control lines. The results are consistent with the hypothesis that some components of the yeast microbiome of D. melanogaster contribute to to flies' tolerance to food substrate with high NaCl concentration.
Characteristics of LiClO4/TTG and LiClO4/DMF electrolytes at different salt concentrations have been experimentally determined by conductometry, 7Li, 1H, 13C NMR. It has been demonstrated that the ...influence of these parameters on the oxygen reaction is due to solvation and electrical conductivity, which, determine the transport characteristics of the reaction participants. In DMF the formation of Li2O2 proceeds predominantly through the solution bulk. In TTG the reaction proceeds predominantly on the electrode surface and does not depend on LiClO4 concentration, which is likely due to the formation of Li2O2 on the electrode surface without passing into the solution bulk with a weak concentration dependence of LiClO4 dissociation in TTG. It cannot be ruled out that the LiClO4 concentration in TTG has an effect on the oxygen reduction mechanism at higher concentrations (> 2 M) because of the complex formation. At any LiClO4 concentration in TTG, the amount of electricity in the cathodic process is lower and the reaction reversibility is higher than in DMF solutions. The key factor responsible for the change in the characteristics of the oxygen reaction in TTG is the decrease in the electrical conductivity and diffusion coefficients of O2 and Li+ with increasing concentration, due to the viscosity of the solution and low dielectric constant.
•Co25.4Cr15Fe37.9Mn3.5Ni16.8Si1.4 alloy was produced by wire arc additive technology.•The microstructure consists mainly of FCC phase but also has CoCr nano phase.•The alloy has good mechanical ...properties.•The chemical are distributed homogeneously.
This study employed wire arc additive manufacturing (WAAM) to fabricate non-equiatomic Co25.4Cr15Fe37.9Mn3.5Ni16.8Si1.4 high-entropy alloy (HEA). Microstructure, elemental distribution, and mechanical properties were investigated. The fabricated HEA has a dendrite structure composed mainly of the FCC phase and CoCr nanoparticles with 1.5–2.5 nm sizes. Energy-dispersive X-ray spectrometry analysis showed that elements are distributed homogeneously in the alloy. Transmission electron microscopy demonstrated the presence of randomly oriented residual dislocations with the density of 1.2∙1010 cm−2. Compressive and tensile tests showed ductile deformation behavior. The yield strength of the alloy is ∼ 279 MPa; ultimate tensile strength is ∼ 500 MPa, and elongation is ∼ 63%.
•Martensitic transformations in several TiNi-based alloys were investigated.•Strain at thermal cycles is observed under lower stress, then at loading/unloading.•This mismatch is associated with the ...different morphologies of B19′-martensite.•Such a feature is observed in alloys with a high value of non-chemical energy.•Strain-stress dependence determines the nonlinear temperature-stress dependence.
In present work, we investigated the martensitic transformations during loading/unloading cycles and stress-assisted cooling/heating cycles in TiNi-based single crystals and polycrystals with different microstructures. During loading/unloading cycles the formation of oriented B19′-martensite is only possible at stress levels higher than σcr(Ms0), so at low stress levels, below σcr(Ms0), the inelastic reversible strain, εtr, is not observed. In contrast, the inelastic reversible strain can be observed during cooling/heating cycles at low stress level σapp<σcr(Ms0). This means that the minimum stress level necessary for oriented martensite formation during cooling/heating cycles is lower than during loading/unloading cycles. An accommodating composition of both the oriented martensite variants and the thermal-induced self-accommodating martensite structure forms during stress-assisted cooling/heating cycles. On the contrary, during loading/unloading cycles the oriented martensite arises via MT from austenite or via the motion of twin boundaries in already-formed self-accommodating structure. It requires higher stress level, which is determined by high value of non-chemical energy ∆GnonchA−M. Different processes occurring during loading/unloading cycles and stress-assisted cooling/heating cycles at low stress levels (σapp<σcr(Ms0)) results in different dependences Msσ(σapp) and σcr(Т) which do not coincide.
•NiMnGa single crystals show high adiabatic cooling values up to 12.3 K.•Elastocaloric effect temperature interval is defined from the crystal orientation.•Orientation dependence of stress hysteresis ...does not affect adiabatic cooling value.•Reverse transition kinetics defines strain rate dependence of elastocaloric cooling.
In this study, the orientation dependence of the elastocaloric effect and superelasticity in Ni50Mn30Ga20 single crystals undergoing L21–10M/14M–L10 martensitic transformations was investigated. The maximum value of the adiabatic temperature change ΔTad at reverse stress-induced martensitic transformations was shown to weakly depends on the orientation and equals 10.8 and 12.3 K in compression along the 001 and 011 directions, respectively. The superelasticity and elastocaloric effect temperature intervals were determined from the crystal orientation and were 80 K from 373 to 453 K for 001-oriented crystals and 30 K from 373 to 403 K for 011-oriented crystals. The strong orientation dependence of stress hysteresis Δσ (Δσ = 50–60 MPa for 001-oriented crystals and Δσ = 110–142 MPa for 011-oriented crystals) did not significantly affect the ΔTad, but determined the efficiency of the material for practical use as a solid state cooling device. The factors influencing the ΔTad(T) dependence were analyzed.
•Al2.1Co0.3Cr0.5FeNi2.1 high entropy alloy was obtained by additive manufacturing.•The microstructure consists of dendrite grains and interdendrite areas.•The key phases detected at the submicro-and ...nano-levels are Al3Ni and (Ni, Co)3Al4.•Content of Al and Ni atoms are prevalent above other elements in the alloy.
The Al2.1Co0.3Cr0.5FeNi2.1 high-entropy alloy was a product of wire arc additive manufacturing. The feeding material was a three-core cable with different element compositions: Al – 99.95%; Cr – 20%, Ni – 80%; Co – 17%, Fe – 54%, Ni – 29%. Optical microscopy techniques were applied to study the microstructure of the produced material, which comprised dendrite grains varying from 4 to 15 µm and interdendritic regions. Scanning electron microscopy demonstrated the dendrite grains were generally made of Al and Ni atoms; the interdendritic regions contained Cr and Fe, whereas Co was distributed quasi-homogenously in the material. Transmission electron microscopy detected main phases to be Al3Ni and (Ni, Co)3Al4. An Al3Ni phase is cubic, and a (Ni, Co)3Al4 phase is spherical. 7 to 10 nm (Ni, Co)3Al4 particles were found along the boundaries of submicron (40–100 nm) Al3Ni phases.
Many natural substances exhibit anti-inflammatory activity and considerable potential in prophylaxis and treatment of allergies. Knowing exact molecular targets, which is required for developing ...these as medicinal products, is often challenging for multicomponent compositions.
In the present study we examined novel polyphenolic substance, a water-soluble fraction of wood lignin (laboratory code BP-Cx-1). In our previous study, a number of polyphenolic components of BP-Cx-1 (flavonoids, sapogenins, phenanthrenes etc.) were identified as the major carriers of biological activity of BP-Cx drug family, and several molecular targets involved in cancer and/or inflammation signaling pathways were proposed based on the results of the in vitro and in silico screening studies.
In the present study, half maximal inhibitory concentration (IC50) of BP-Cx-1 was established with a radioligand method and a range of IC50 values between 22.8 and 40.3 μg/ml were obtained for adenosine receptors A1, A2A and prostaglandin receptors EP2, IP (PGI2). IC50 for serotonin 5-HT1 and for glucocorticoid GR receptors were 3.0 μg/ml and 12.6 μg/ml, respectively, both being within the range of BP-Cx-1 concentrations achievable in in vivo models.
Further, distribution of 3H labelled BP-Cx-1 in NIH3T3 murine fibroblasts and MCF7/R carcinoma cells was studied with autoradiography. 3H-BP-Cx-1 (visualized as silver grains produced by tritium beta particles) was mainly localized along the cell membrane, in the perinuclear region and in the nucleus, suggesting ability of BP-Cx-1 to enter cells and bind to membrane or cytosol receptors.
In our experiment, we observed the effect of BP-Cx-1 on maturation of dendritic cells (DCs): downregulation of expression of the lipid-presentation molecule CD1a, co-stimulatory molecules CD80, CD83 and CD 40, decreased production of pro-inflammatory cytokines IL-4 and TNF-α and increased production of anti-inflammatory cytokine IL-10. It is hypothesized that 3H-BP-Cx-1 detectable in the nucleus is part of the activated GR complex, known to be involved in regulation of transcription of genes responsible for the anti-inflammatory response. Based on IC50, cell distribution data and results of the experiment with DCs it is suggested that the in vivo effects of BP-Cx-1 are mediated via GR and 5-HT1 receptors thus promoting development of tolerogenic effector function in dendritic cells.
•Water-soluble fraction of wood lignin (BP-Cx-1) targets GR and 5-HT1 receptors.•3H-BP-Cx-1 is detectable on cell membranes, perinuclear region and cell nucleus.•Effects of BP-Cx-1 on dendritic cells resemble those of corticosteroids or serotonin.•BP-Cx-1 induces tol-DCs, reported to play a role in treatment of autoimmune diseases.
•Two-way shape memory effect can be induced without lengthy trainings in NiTiHf alloy.•Effective regime of stress-induced martensite aging in NiTiHf alloy is obtained.•The biggest uniaxial two-way ...shape memory effect of 2.3% is induced in NiTiHf alloy.
This study investigated the effect of stress-induced martensite aging on thermoelastic martensitic transformations in Ni50.3Ti32.2Hf17.5 polycrystals containing nanosized dispersed H-phase particles. It was found that stress-induced martensite aging at 428 K for 12 h, under an applied tensile stress of 300 MPa, results in an increase of reversible strain (~37%) with low applied stresses during cooling-heating cycles and induces a tensile two-way shape-memory effect of 2.3% (~50% of the maximum reversible strain). Moreover, stress-induced martensite aging along with detwinning of (0 0 1) compound internal twins under stress provide an increase of temperature intervals of martensitic transformations by 10 ÷ 12 K due to accumulation of elastic energy.
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