Cross sections for the production of stable and unstable isotopes with charge numbers from one to eight in <Superscript>16</Superscript>O<Emphasis Type="Italic">p</Emphasis> collisions at 3.25 <Emphasis Type="Italic">A</Emphasis> GeV/<Emphasis Type="Italic">c</Emphasis>

New experimental data are presented for the inclusive cross sections both for the production and for the yield of stable and unstable isotopes with charge numbers from one to eight in ¹⁶Op collisions at 3.25 A GeV/c.     

Adsorption of CO2 in metal organic frameworks of different metal centres: Grand Canonical Monte Carlo simulations compared to experiments

A Grand Canonical Monte Carlo study has been performed in order to compare the different CO₂ adsorption mechanisms between two members of the MIL-n family of hybrid metal-organic framework materials. The MIL-53 (Al) and MIL-47 (V) systems were considered. The results obtained confirm that there is a structural interchange between a large pore and narrow pore forms of MIL-53 (Al), not seen with the MIL-47 (V) material, which is a consequence of the presence of μ ₂-OH groups. The interactions between the CO₂ molecules and these μ ₂ OH groups mainly govern the adsorption mechanism in this MIL-53 (Al) material. The subsequent breaking of these adsorption geometries after the adsorbate loading increases past the point where no more preferred adsorption sites are available, are proposed as key features of the breathing phenomenon. After this, any new adsorbates introduced into the MIL-53 (Al) large pore structure experience a homogeneous adsorption environment with no preferential adsorption sites in a similar way to what occurs in MIL-47 (V).     

Synthesis of Aminotelechelic Polymers with the Redox System TiCl3/NH2OH in the Hydrochloric Aqueous Phase. I. Polymerization Possibilities and Limits

Among recent progress in the field of macromolecular chemistry, of considerable interest has been the synthesis of α, ω-ordifunctional polymers. These polymers, called “telechelic” polymers, are interesting because many reactions are possible on their functional end-groups:     

Influence of thermal activation on dislocation inelasticity of LiF crystals with different impurity compositions

The method of double piezoelectric oscillator is used to investigate the influence of thermal activation (293–573 K) on the dislocation inelasticity and dislocation structure of the annealed LiF crystals having different impurity compositions. On curves illustrating the dependence of the internal friction on the strain amplitude δ(ε₀), a peak having a hysteresis nature is established; it is displaced toward smaller ε₀ values with increasing temperature. A subsequent increase in δ(ε₀) after passage of the peak is caused by the processes of dislocation multiplication upon exposure to ultrasound. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 90–96, August, 2008.     

X-ray diffraction method of the radial electron density distribution. Structure of nanophase supports and supported catalysts

The structure of the synthesized title compound is characterized by IR, UV-visible spectroscopy, and single crystal X-ray diffraction (XRD). The new compound (C₁₈H₂₃NS) crystalizes in the monoclinic P2₁/c space group. In addition to the crystal structure from the X-ray experiment, the molecular geometry, vibrational frequencies, atomic charge distribution, and frontier molecular orbital (FMO) analysis of the title compound in the ground state are calculated by density functional teory (B3LYP) with 6-311G(d,p) and 6-31G(d,p) basis sets. The results of the optimized molecular structure are presented and compared with the experimental values. The computed vibrational frequencies are used to determine the types of molecular motions associated with each of the observed experimental bands. To determine the conformational flexibility, the molecular energy profile of (1) is obtained by semi-empirical (AM1) and (PM3) calculations with respect to a selected degree of torsional freedom. Moreover, molecular electrostatic potential (MEP) and thermodynamic parameters of the title compound were calculated by the theoretical methods.     

Giant Pores in a Chromium 2,6‐Naphthalenedicarboxylate Open‐Framework Structure with MIL‐101 Topology

Large, larger, …? Replacement of 1,4‐benzenedicarboxylate by 2,6‐naphthalenedicarboxylate in the MIL‐101 structure leads to an isoreticular mesoporous framework containing cages with diameters of 39 and 46 Å. High‐throughput methods are employed to determine appropriate reaction conditions. The microcrystalline compound is characterized by molecular simulation techniques, powder X‐ray diffraction, N₂‐sorption, and TEM investigations.