Study of inclusive production of π± and protons in\bar p p interactions at 32 GeV/c

Results are presented on the inclusive production of π^± mesons and protons in \(\bar p\) p interactions at an incident antiproton momentum of 32 GeV/c in the MIRABELLE bubble chamber, based on a sample of 55,000 inelastic events. The spectra of π⁺(π^?) andp( \(\bar p\) ) are separated in the whole kinematically admitted region of phase space by a statistical method. The semi-inclusive and inclusive cross sections and the main average characteristics of π andp production are calculated. The invariant differential cross sections are studied as functions of the Fevnman scaling variablex, the rapidity and the transverse momentum. Thex distribution of π^± mesons in the proton fragmentation region does not show any significant contribution from quark exchange or annihilation processes. A possible contribution of hard quark scattering on mesons or baryons is observed for large transverse momenta.     

IR Spectra of N,N′-Ethylene-Bis(salicylaldiminates) and N,N′-ethylene-Bis(acetylacetoniminates) of Ni(II), Cu(II), and Zn(II)

Vibrational spectra of N,N′-ethylene-Bis(salicylaldiminaates) and N,N′-ethylene-Bis(acetylacetoniminates) of nickel (II), copper (II), and zinc (II) are studied experimentally (IR spectroscopy, 400–4000 cm⁻¹) and theoretically (B3LYP), band assignment is given, and the distribution of potential energy of normal vibrations in internal coordinates is studied. Differences between vibrational spectra of the complexes are discussed. Thermodynamic functions of gas-phase complexes corresponding to temperatures of 298 and 800 K are calculated.     

Synthesis of mixed-ligand alkali earth element dipivaloylmethanates with <Emphasis Type="Italic">o</Emphasis>-phenanthroline

A one-step method for the synthesis of volatile barium and strontium complexes [M(Thd)₂(Phen)₂] (M = Ba, Sr; Thd is the dipivaloylmethane anion) was developed. The method is based on the reaction of metal hydroxide octahydrates with dipivaloylmethane (HThd) and o-phenanthroline (Phen) accompanied by removal of water from the reaction mixture as a solvent-water azeotrope. In the case of calcium hydroxide monohydrate, a similar interaction causes destruction of the dipivaloylmethanate ligand to give a mixed-ligand calcium complex with the pivalate anion and o-phenanthroline.     

The thermodynamic characteristics of swelling of novocaine hydrochloride crystals brought into isopiestic contact with water-salt solutions

The interaction of water with solid Novocaine hydrochloride was studied isopiestically over a wide range of solvent relative activities. The Gibbs energy of water interaction with Novocaine hydrochloride crystals was calculated. A scheme of intermolecular interactions in the water-Novocaine hydrochloride system was suggested.     

Zinc(II) complexes with Schiff bases derived from ethylenediamine and salicylaldehyde: the synthesis and photoluminescent properties

The effect of the nature of organic ligands and complex formation on the photoluminescent characteristics (relative quantum yield, excited-state lifetime) and thermal stability of tetradentate Schiff bases (H₂L), derivatives of salicylaldehyde (H₂(SAL)¹, H₂(SAL)²), o-vanillin (H₂(MO)¹, H₂(MO)²) with ethylenediamine and o-phenylenediamine, and their zinc(II) complexes was studied. Zinc(II) complexes were synthesized by the reaction of H₂L with Zn(AcO)₂·2H₂O in MeOH at room temperature or under reflux. In the case of H₂L = H₂(SAL)², H₂(MO)¹, H₂(MO)², complexes of the composition ZnL·H₂O were isolated irrespective of the temperature. For H₂L = H₂(SAL)¹, the reaction results in Zn(SAL)¹·H₂O at room temperature and in anhydrous dimeric complex [Zn(SAL)¹]₂ under reflux. Density functional calculations of H₂L and ZnL confirmed that (1) luminescence of these compounds is due to the π-π* transition between orbitals of the organic ligand and (2) enhancement of conjugation of the chain and introduction of electron-donating substituents lead to a decrease of the energy gap and, there-fore, to a bathochromic shift of the emission maximum. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1846–1855, September, 2008.     

Computer simulation of the hydration of sulfocation exchanger containing imino acid

The mechanism of formation of hydrate structures in the system sulfo exchanger-imino acid was suggested. The mutual position of fixed ion, imino acid, and water molecules was determined in cation exchanger. The conclusion was made on the presence of water molecule between the functional group of sorbent and counterion of imino acid. It was demonstrated that the mechanism of sorption of proline and hydroxyproline is performed by the break of bond between water molecules and protonation of carboxylic group of imino acid.     

A Microcalorimetric Study of the Heat Effects of Sorption of Imino Acids on KU-2 × 8 H-Sulfocation Exchanger

The thermokinetic characteristics of sorption of proline and hydroxyproline on H-sulfocation exchanger were determined. The absorption of dipolar imino acid ions by the cation exchanger was found to be an exothermic process accompanied by a decrease in the enthalpy component of sorption. The enthalpy character of sorption was to a greater extent characteristic of hydroxyproline.     

Effect of the content of ethyl cellulose-rubber blend on physicochemical properties of adhesive compositions

Results of comprehensive systematic physicochemical studies of the blends of ethyl cellulose and butadiene-acrylonitrile rubbers are reported. It is shown that the addition of butadiene-acrylonitrile rubbers to ethyl cellulose results in the formation of ethyl cellulose-butadiene-acrylonitrile rubber thermoelastoplastic complexes due to the elastification of the thermoplastic polymorphous structure of ethyl cellulose with enhanced impact strength and heat resistance.