Pleiades Publishing Ltd

Thermodynamic properties of the cholesteryl myristate (CM) and its binary mixture CM/PCPB (p-pentylphenyl-2-chloro-4(p-pentylbenzoyl)-benzoate) are studied at the concentrations of xPCPB = 0.052 and 0.219 as a function of temperature near the cholosteric/smectic A transition. By analyzing the observed molar volume from the literature, the temperature dependences of the thermal expansion, isothermal compressibility and the difference in the specific heat are calculated and, the Pippard relations are established for those compounds close to the cholesteric/smectic A transition. Predictions of the thermodynamic quantities and the Pippard relations can be examined by the experimental measurements of the CM and its binary mixture of CM/PCPB close to the cholesteric/smectic A transition.

The solvent extraction of Cr(VI) using trioctylphosphine oxide (TOPO), 2,4,4-trimethylpentyl phosphinic acid (Cyanex 272) and their mixture in cyclohexane was investigated. From the pH variation study, the extraction is found to be decreased with increase in pH and maximum extraction was noticed around pH 1.0. Maximum percentage extraction of Cr(VI) with 0.1 M concentration of TOPO, Cyanex 272, and their mixture were found to be 96.7, 46.5, and 97.3%, respectively. Highest loading capacity of 586 mg/L was reported using 0.05 M of TOPO + Cyanex 272. Synergism was observed for each set of experiment. TOPO was found to be better synergist than Cyanex 272. The order of extraction when investigating the different extraction parameters were TOPO + Cyanex 272 > TOPO > Cyanex 272.

Iron oxide nanopowders are synthesized via chemical precipitation. It is shown that synthesis produces an iron oxide phase with a magnetite structure (either a magnetite–maghemite solid solution or a mixture of this solid solution and goethite). The sizes of the CSR and particles for the main phase are ~10–20 nm. The synthesized iron oxide powders have developed surfaces, specific surface area SBET ≈ 92 and 117 m2/g, and identical fairly large specific pore volumes ( $${{V}_{P}}{{_{{/{{P}_{0}} \to 0.99}}}_{{}}}$$ = 0.35 cm3/g). It is shown that additional in situ ultrasonic treatment of the magnetic iron oxide nanoparticles in the mother liquor results in abrupt oxidation of iron(II) ions and creates a nonmagnetic impurity phase of goethite.

The preferential solvatation of human serum albumin (HSA) in dimethylsulfoxide (DMSO) aqueous solutions were studied using the densitometry method. It has been shown that at DMSO low concentrations HSA undergoes to preferential hydration, but at DMSO higher concentrations preferential binding of DMSO molecules to protein occurs. It has been estimated that DMSO exhibits stabilizing/destabilizing effect on HSA structure which is explained in terms of hydration/solvatation of protein, on the one hand, and the medium structure enhancement/disruption around the protein molecule, on the other hand.

We investigate diffusivity and conductivity in the context of electronic transport in crystalline cadmium oxide by knowing the electron concentration in CdO as a function of the partial pressure of oxygen in the deposition process of the material in question. From the chemical kinetics of the reaction by which CdO is formed, first we consider an approximate relationship for the electron concentration in terms of the above pressure. In fact, by taking into account this relationship and other issues, we determine the product diffusivity $$ \times $$ conductivity in crystalline CdO. This product can be considered as a significant figure of merit.

We first report the hybrids of TiO2 and graphene (Gr) used as the support of Pd nanoparticles, showing high performance electrocatalysts for formic acid oxidation. The hybrids are prepared with the solvothermal method, and tetrabutyl titanate and graphene-oxide (GO) are used as the precursors. The initial mass ratios of Ti:GO in the precursors are 0.07, 0.15, 0.26, 0.60, respectively. Compared to Pd/graphene, the as-obtained Pd/TiO2–Gr electrocatalysts exhibit higher catalytic activity and stability. Among them, the Pd/TiO2–Gr (Ti : GO = 0.26, initial mass ratio) exhibit the highest activity. Its current density is about 3.1 times of Pd/graphene, and the agglomeration of Pd metal that can be seen in Pd/graphene has been inhibited in the as prepared Pd/TiO2–Gr. Thus the electrocatalytic performance of Pd for formic acid oxidation is greatly improved by the binary TiO2–graphene support.

Hydrogen peroxide was found to oxidize 1-phenylethanol to acetophenone in acetonitrile homogeneous solution efficiently at room temperature in the presence of a dimeric complex of manganese (IV) [LMn(O)3MnL](PF6)2(where L = 1,4,7-trimethyl-1,4,7-triazacyclononane) as the catalyst and oxalic acid as a co-catalyst. The number of catalytic cycles was 15 000 3 h after the onset of the reaction. The dependences of the initial rate of acetophenone accumulation on the initial concentrations of the reagents were studied. Based on an analysis of the kinetic data, we conclude that phenylethanol is oxidized by a manganyl particle containing an Mn = O fragment that interacts competitively with hydrogen peroxide.