Phase transitions in Cs5(HSO4)2(H2PO4)3 crystal

The symmetry (sp. gr.I $\bar 4$ 3d) and lattice parameters have been determined for the first time for Cs₅(H₂SO₄)₂(H₂PO₄)₃ crystals in the temperature range from 172 to 390 K. The thermal and optical properties of crystals, as well as their conductivity, have been investigated at elevated temperatures. It is shown that a crystal heated to T = 365 K undergoes a phase transition with symmetry lowering to the tetragonal phase (with the parameters a = 4.965(1) Å and c = 5.016(1) Å), while at T ≈ 390 K a phase transition to the cubic phase is presumably observed. With a decrease in temperature, a phase transition without a change in symmetry occurs at T = 240 K.     

Influence of a Coronal Mass Ejection on the Solar Cosmic Ray Acceleration by a Shock Wave in the Lower Solar Corona

Journal of Experimental and Theoretical Physics - Based on the theory of diffusive shock acceleration of charged particles, we have theoretically studied the spectra of protons produced by a shock...     

Multifunctional materials exhibiting spin crossover and liquid-crystalline properties

The physical characterization of a new class of Fe(II) multifunctional SCO materials exhibiting spin crossover and liquid crystalline properties in the room temperatures region is reported. Mössbauer spectroscopy, magnetic, differential scanning calorimetry (DSC), X-ray powder diffraction (XRD) and optical polarizing microscopy studies have been performed on such materials.     

Appearance of characteristics of formation of resorcin-formaldehyde polymer in the turbidity and Raman spectra

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 2, pp. 206–210, February, 1991.     

Low-field ion microscopy

Experimental data on field ion emission under high partial pressures of water vapor at room temperature are reported. A method for obtaining low-field ion images in the presence of water vapor is proposed and the potentialities, limitations, and prospects of using images in microscopy are considered.     

Structure and magnetic properties of iron–platinum particles with <Emphasis Type="Italic">γ</Emphasis>-ferric-oxide shell

Nanoparticles of solid solution Fe _x Pt_1?x , where 0.25≥x≥0 (?fcc lattice) with γ-Fe₂O₃ shell (lattice of the spinel type) were synthesised and characterised by high-resolution transmission electron microscopy, energy dispersive X-ray analysis, electron energy loss spectroscopy, Mössbauer spectroscopy and magnetometry. From the point of view of magnetic properties, such two-phase particles are interesting because their core is antiferromagnetic or paramagnetic (at very small values of x) whereas the shell is ferrimagnetic. The size of the particles was in the range of several nanometers. The Mössbauer measurements revealed a blocking temperature of about 100 K above which the particles are superparamagnetic. Towards lower temperatures, the magnetic characteristics of an ensemble of such particles show an increase of magnetic rigidity.