Mesoscopic Strain Fields Measurement During the Allotropic α − γ Transformation in High Purity Iron

The allotropic phase change from ferrite to austenite represents a moment of massive interplay between the microstructural and mechanical states of iron. The difference of compacity between the two phases induces a microplastic accommodation in the material at grain scale. However, mechanical heterogeneities resulting from the transformation process remain challenging to characterise due to the high temperature conditions it is associated with. We developed experimental equipment for in situ observation of α ? γ and γ ? α transformations. Images of the surface of an iron sample taken by an optical camera were used as input for a Digital Image Correlation (DIC) routine. Special care was taken to maximize image resolution to capture sub-grain phenomena. Observations show that, at the mesoscopic scale, shear strain fields exhibit strong localisations that are evidence of transformations that are occurring.

     

Synthesis of Nitro,Amino, and Halo Derivatives of 2-Ethyl-2-methyl-2,3-dihydro-1H-indole

Russian Journal of Organic Chemistry - The nitration, oxidative halogenation, and radical bromination and chlorination of 2-ethyl-2-methyl-2,3-dihydro-1H-indole afforded the corresponding nitro,...     

Structure of Zinc Nanotubes

Crystallography Reports - The formation of Zn-based nanotubes by electrochemical synthesis in pores of template polymer matrices is considered. It is established that the number of defects in the...     

Single-Crystal Synthesis and Structures of Rb-Boroleucite Rb(BSi2)O6 and Boropollucite Cs(BSi2)O6 at 293 and 120 K

Crystallography Reports - The structures of Rb-boroleucite Rb1.0(B0.333Si0.667)3O6 and boropollucite Cs0.87(B0.290Si0.710)3O6 were studied using single crystals, which were prepared under...     

Thermal analysis and FT-IR spectroscopy of synthetic clay mineral mixtures

Journal of Thermal Analysis and Calorimetry - This article investigates the visualizations of heatlines in a natural convection magnetohydrodynamic flow from a vertical cylinder via heat function...     

Photoelectrochemical study of La2NiO4 synthesized using citrate sol gel method—application for hydrogen photo-production

Journal of Solid State Electrochemistry - The semi conducting properties of La2NiO4 synthesized through sol gel method are studied for the first time using photoelectrochemistry. The X-ray...     

Imidazotetrazines as Weighable Diazomethane Surrogates for Esterifications and Cyclopropanations

Diazomethane is one of the most versatile reagents in organic synthesis, but its utility is limited by its hazardous nature. Although alternative methods exist to perform the unique chemistry of diazomethane, these suffer from diminished reactivity and/or correspondingly harsher conditions. Herein, we describe the repurposing of imidazotetrazines (such as temozolomide, TMZ, the standard of care for glioblastoma) for use as synthetic precursors of alkyl diazonium reagents. TMZ was employed to conduct esterifications and metal‐catalyzed cyclopropanations, and results show that methyl ester formation from a wide variety of substrates is especially efficient and operationally simple. TMZ is a commercially available solid that is non‐explosive and non‐toxic, and should find broad utility as a replacement for diazomethane.     

Artificial Precipitation of Energetic Electrons in a Magnetically Conjugate Region of the Ionosphere Relative to the Sura Facility

Radiophysics and Quantum Electronics - We analyze the features of energetic electron precipitation (with the maximum energy E ≥ 150 keV) from the Earth’s radiation belt into a...     

Effect of the Morphology of an Ensemble of ZnO Microrods on the Optical and Luminescence Properties

JETP Letters - From measurements of the oscillatory magnetoresistance in weak perpendicular magnetic fields, we found that the quantum oscillations in two-dimensional electron systems in Si-MOS...     

BGK and Fokker-Planck Models of the Boltzmann Equation for Gases with Discrete Levels of Vibrational Energy

We propose two models of the Boltzmann equation (BGK and Fokker-Planck models) for rarefied flows of diatomic gases in vibrational non-equilibrium. These models take into account the discrete repartition of vibration energy modes, which is required for high temperature flows, like for atmospheric re-entry problems. We prove that these models satisfy conservation and entropy properties (H-theorem), and we derive their corresponding compressible Navier–Stokes asymptotics.