Синтез и оптические свойства кристаллов метабората меди, легированного никелем

This work presents information on the growth and spectroscopic study of single crystals of copper metaborate doped with nickel Cu1-xNixB2O4 (x = 0.05, 0.1). In the absorption spectra of both crystals, satellites related to Cu centers distorted by impurity Ni atoms were observed near the lines of zero phonon transitions. Polarization studies in the isotropic ab-plane of the tetragonal crystal Cu1-xNixB2O4 show the presence of linear magnetic dichroism in the magnetically ordered state, which was previously observed both in manganese-doped and undoped copper metaborates CuB2O4. The temperature of magnetic phase transitions into the collinear antiferromagnetic and into helicoidal structures, TN = 19.1 K and T* = 8.6 К, respectively, were determined from the temperature dependence of the dichroic signal.

Evaluation of Electrochemical and Anticorrosion Properties of Polyaniline-Fly Ash Nanocomposite

In India, the thermal station generates approximately 6.9 × 10 7 tons of fly ash (FA) as a waste by-product. As part of this work, little attempt was made to produce useful materials from waste material. In our current research, polyaniline- (PANI-) fly ash (FA) nanocomposite (PFNC) was synthesized using an in situ polymerization method. The synthesized composites were characterized by employing advanced analytical, microscopic, and spectroscopic tools. The results of the X-ray diffraction (XRD) analysis confirm the effective reinforcement of FA into PANI in PFNC. The presence of functional groups in PFNC has been confirmed by Raman and FT-IR spectroscopic techniques. The SEM micrographs of the nanocomposite revealed the presence of agglomerated and fragmented structures in PFNC. The weight loss for PFNC was observed to occur in three stages as revealed by thermogravimetric analysis (TGA). UV-visible spectra for PFNC proved that FA stabilized the PANI in emeraldine form. Electrodynamic polarization studies were conducted to explore the corrosion resistance of nanocomposite-coated mild steel. The corrosion current density ( i corr ) for PFNC-coated mild steel (MS) specimens was found to decrease when compared to the bare substrate, indicating superior corrosion resistance in PFNC-coated substrate. Similarly, Tafel and cyclic polarization studies too confirmed superior anticorrosion property for MS coated with PFNC.

Will Failed Insurrection Lead to Terrorism in the United States?

The following discussion outlines the attractions of a strategy of terrorism and its implications for political order. It also argues that a body of knowledge has been built up over time that provides a foundation for explaining current events. Research has shown that terrorism can be an effective substitute for the mobilization of large numbers when that mobilization is thwarted. Terrorism can sustain an illusion of power, provoke official over-reaction and community counter-mobilization, and deepen political polarization. Studies also suggest that if a broader movement dissolves, the followers who remain strengthen their commitment and become more inclined to violence. The future threat environment is most likely to be multidimensional, with multiple groups cooperating and competing along with individual actors who perceive themselves to be part of an ideological collectivity.

Spin Experimentation with Unpolarized Colliding Beams at the LHC

A brief recollection of the problems related to a significant hyperon polarization observed in pp-collisions is given with an emphasis on the general role of spin in the dynamics of hadron interactions. The old, unsolved problem of the observation of a significant hyperon polarization can provide new insights as a result of the measurements of energies at the LHC; in combination with other measurements, these can be used to tag the QGP formation in pp-collisions with colliding beams. Polarization studies in the processes of hyperon production do not require the use of polarized beams or targets and can be performed in the existing experimental environment at the LHC. Model predictions based on the chiral dynamics and pictures of the impact parameter are presented for the illustration of a possible dynamical mechanism that leads to a hyperon polarization.

Study of Coatings Formed on Zirconium Alloy by Plasma Electrolytic Oxidation in Electrolyte with Submicron Yttria Powder Additives

Coatings with thickness 40 to 150 μm were formed by plasma electrolytic oxidation (PEO) on the zirconium alloy Zr-1Nb (Zr-1% Nb) in the slurry electrolyte containing 9 g/L Na2SiO3 5H2O, 5 g/L Na(PH2O2) and 6 g/L submicron Y2O3 yttria powder during 60 min under the AC electrical mode at current densities 20; 30 and 40 A/dm2. The surface morphology, structure, composition, and corrosion-protective ability of the formed coatings have been analyzed. At PEO current density 30 A/dm2, a predominantly tetragonal phase of zirconia was formed in coatings. Increasing the PEO current density up to 40 A/dm2 promoted the formation of the coating surface layer containing submicron yttria particles. Electrochemical polarization studies in 0.5% LiOH solution showed that PEO coatings demonstrated high corrosion-protective ability. The dependence of the polarization currents on the PEO current density was found to be inconsequential.

Are GRMHD Mean-Field Dynamo Models of Thick Accretion Disks SANE?

The remarkable results by the Event Horizon Telescope collaboration concerning the emission from M87* and, more recently, its polarization properties, require an increasingly accurate modeling of the plasma flows around the accreting black hole. Radiatively inefficient sources such as M87* and Sgr A* are typically modeled with the SANE (standard and normal evolution) paradigm, if the accretion dynamics is smooth, or with the MAD (magnetically arrested disk) paradigm, if the black hole’s magnetosphere reacts by halting the accretion sporadically, resulting in a highly dynamical process. While the recent polarization studies seem to favor MAD models, this may not be true for all sources, and SANE accretion surely still deserves attention. In this work, we investigate the possibility of reaching the typical degree of magnetization and other accretion properties expected for SANE disks by resorting to the mean-field dynamo process in axisymmetric GRMHD simulations, which are supposed to mimic the amplifying action of an unresolved magnetorotational instability-driven turbulence. We show that it is possible to reproduce the main diagnostics present in the literature by starting from very unfavorable initial configurations, such as a purely toroidal magnetic field with negligible magnetization.

Lignin from termite frass: a sustainable source for anticorrosive applications

The present study reports a sustainable source of lignin, from termite frass. Lignin was extracted using Klason’s method and subjected to polarization studies to check the inhibition efficiency and measured the electrochemical performance of the coated sample on the carbon steel using electrochemical impedance spectroscopy. The anticorrosive property was determined in a simulated corrosive environment (0.1 M NaOH and 0.5 M NaOH). The morphological analysis of the surface of both bare metal and the lignin-coated ones, before and after exposure to the corrosive environment, was recorded using atomic force microscopy (AFM), scanning electron microscopy (SEM), and energy-dispersive X-Ray spectroscopy (EDX). The lignin showed maximum inhibition efficiency at 600 ppm in 0.5 M NaOH solution. Moreover, the lignin coated on carbon steel exhibited about 70% corrosion inhibition efficiency as recorded by potentiodynamic polarization studies and electrochemical impedance spectroscopy. The AFM and SEM analyses further corroborated the protection of the metal surface from corrosion when coated with lignin. Hence, the study suggests lignin from termite frass as a sustainable biological source suitable for anticorrosive applications. Graphic abstract

Wise reasoning, intergroup positivity, and attitude polarization across contexts

We hypothesized that a wisdom-based reasoning process comprised of epistemic humility, accounting for context, and integrating different perspectives and interests, would be helpful in overcoming intergroup bias and attitude polarization in societal conflicts. Here we test the hypothesis using both the Situated Wise Reasoning Scale and experimental induction. In each study, we recruited participants who self-identified as members of a group implicated in an ongoing intergroup situation. In five correlational studies (Studies 1-5) we examined the relations between measured wise reasoning and intergroup positivity and attitude polarization. In two experiments, we tested the effects of a brief online wise-reasoning thought exercise on intergroup positivity and polarization (Studies 6-7), and charitable behaviors to an outgroup (Study 6). We found that wise reasoning relates to more positivity toward outgroups and less attitude polarization across different groups and conflicts. The results have implications for theory and may also have implications for future research on interventions to improve intergroup relations.

Wise reasoning, intergroup positivity, and attitude polarization across contexts

We hypothesized that a wisdom-based reasoning process comprised of epistemic humility, accounting for context, and integrating different perspectives and interests, would be helpful in overcoming intergroup bias and attitude polarization in societal conflicts. Here we test the hypothesis using both the Situated Wise Reasoning Scale and experimental induction. In each study, we recruited participants who self-identified as members of a group implicated in an ongoing intergroup situation. In five correlational studies (Studies 1-5) we examined the relations between measured wise reasoning and intergroup positivity and attitude polarization. In two experiments, we tested the effects of a brief online wise-reasoning thought exercise on intergroup positivity and polarization (Studies 6-7), and charitable behaviors to an outgroup (Study 6). We found that wise reasoning relates to more positivity toward outgroups and less attitude polarization across different groups and conflicts. The results have implications for theory and may also have implications for future research on interventions to improve intergroup relations.