Thermodynamics of Mixed-Ligand Complex Formation of Mercury(II) Ethylenediaminetetraacetate with Ethylenediamine and Hexamethylenediamine in an Aqueous Solution

The thermodynamic parameters (logK, Δ _r G ⁰, Δ _r H, Δ _r S) of formation of the HgEdtaL^2?, HgEdtaHL^? and (HgEdta)₂L^4? complexes (L = NH₂(CH₂)₂NH₂, NH₂(CH₂)₆NH₂) have been determined by the calorimetric and pH-metric methods at 298.15 K and the ionic strength I = 0.5 (NaClO₄). The most probable coordination mode for the complexone and an ancillary ligand in the composition of the mixed complexes was discussed.     

Reaction of singlet difluorocarbene with 6-methylpyrimidin-4(3<Emphasis Type="Italic">H</Emphasis>)-one derivatives

Regularities of regioselective O-difluoromethylation of 6-methylpyrimidin-4(3H)-one derivatives with difluorocarbene generated in situ were studied.     

Ziegler-type nickel-based hydrogenation catalysts: The effect of the water content of the nickel precursor on the size and nature of the resulting particles

The size and nature of the nanoparticles forming in systems based on Ni(acac)₂ · nH₂O (n = 0, 0.5, 3.0) and AlEt₃ have been determined by high-resolution electron microscopy and X-ray microanalysis. The nickel cluster size depends on the water content of the precursor. The average particle diameter increases from 1.2 nm (Ni(acac)₂ · 0.5H₂O precursor) to 2.4 nm (Ni(acac)₂ · 3H₂O precursor). A homogeneous solution forms in the Ni(acac)₂–5AlEt₃ system, as was demonstrated by examining the system under an electron microscope whose resolving power allows particles larger than 0.7 nm to be detected.     

Decisive Role of Interference Effects in Describing T-Odd Asymmetries in Reactions Induced by Polarized Cold Neutrons

Physics of Atomic Nuclei - A detailed analysis of T-odd asymmetries in the reactions of true ternary fission of nuclei that involves the emission of prescission alpha particles is performed within...     

Photofission induced by linearly polarized photons

The asymmetry coefficients of fragments’ angular distribution (FAD) for fission of ^{234, 236, 238}U and ^{238, 240, 242}Pu isotopes, induced by linearly polarized photons, have been calculated. The optimal energies for observing the polarization parts in this asymmetry are found. Based on the experimental data on FAD for ²³²Th photofission induced by linearly polarized photons with the maximum energy E _γ = 10 MeV (with neglect of the contribution of absorption of electric quadruple photons), it is shown that the theoretical and experimental FAD asymmetry coefficients coincide within standard deviations. Original Russian Text ? S.G. Kadmensky, L.V. Titova, O.S. Khmelevskaya, 2009, published in Izvestiya Rossiiskoi Akademii Nauk. Seriya Fizicheskaya, 2009, Vol. 73, No. 6, pp. 878–881.     

The thermodynamic functions of fullerene derivative (<Emphasis Type="Italic">t</Emphasis>-Bu)<Subscript>12</Subscript>C<Subscript>60</Subscript> over the temperature range from <Emphasis Type="Italic">T</Emphasis> → 0 to 420 K

The temperature dependence of heat capacity C _p ^o = f(T) of fullerene derivative (t-Bu)₁₂C₆₀ has been measured by a adiabatic vacuum calorimeter over the temperature range T = 6–350 K and by a differential scanning calorimeter over the temperature range T = 330–420 K for the first time. The low-temperature (T ≤ 50 K) dependence of the heat capacity was analyzed based on Debye’s the heat capacity theory of solids and its fractal variant. As a consequence, the conclusion about structure heterodynamicity is given. The experimental results have been used to calculate the standard thermodynamic functions C _p ^o (T), H ^o(T)−H ^o(0), S ^o(T) and G ^o(T) − H ^o(0) over the range from T → 0 to 420 K. The standard entropy of formation at 298.15 K of fullerene derivative under study was calculated. The temperature of decomposition onset of derivative was determined by differential scanning calorimetery and thermogravimetric analysis. The standard thermodynamic characteristics of (t-Bu)₁₂C₆₀ and C₆₀ fullerite were compared.     

Solubility and stability of (NH<Subscript>4</Subscript>)<Subscript>2</Subscript>SO<Subscript>4</Subscript>·H<Subscript>2</Subscript>O<Subscript>2</Subscript> in organic and aqueous-organic media

Solubility and stability of (NH₄)₂SO₄·H₂O₂ in organic solvents (glycerol, ethylene glycol, TOSOL-A40 OM antifreeze), in mixtures of an organic solvent and water, and in pure water was studied. Crystallographic properties of the ammonium sulfate precipitating from aqueous-organic solvents and aqueous solutions in various time intervals and differing from ordinary (NH₄)₂SO₄ in solubility and one of crystallographic parameters were analyzed.     

Interlayer current near the edge of an InAs/GaSb double quantum well in proximity with a superconductor

We investigate charge transport through the junction between a niobium superconductor and the edge of a two-dimensional electron-hole bilayer, realized in an InAs/GaSb double quantum well. For the transparent interface with a superconductor, we demonstrate that the junction resistance is determined by the interlayer charge transfer near the interface. From an analysis of experimental I?V curves, we conclude that the proximity-induced superconductivity efficiently couples electron and hole layers at low currents. The critical current demonstrates periodic dependence on the in-plane magnetic field, while it is monotonic for the field that is normal to the bilayer plane.