Presowing Treatment of Spring Wheat Seeds by a Pulsed Electron Beam in the Atmosphere

High Energy Chemistry - The purpose of this work is to optimize the conditions of presowing treatment of spring wheat seeds with a low-energy pulsed electron beam. The absorbed dose in wheat has...     

One-pot five-component high diastereoselective synthesis of polysubstituted 2-piperidinones from aromatic aldehydes,nitriles, dialkyl malonates and ammonium acetate

Molecular Diversity - A novel five-component diastereoselective synthesis of polysubstituted 2-piperidinones is reported. The Knoevenagel condensation–Michael addition–Mannich cascade...     

Quantum‐chemical study of the singlet oxygen emission

Intensity distribution in rotational lines of the 0–0 band of the a¹Δ_g → X³Σ transition in the oxygen molecule at λ = 1270 nm is studied by quadratic response (QR) method in a framework of multiconfiguration self‐consisted field (MCSCF) theory. The distance dependence of the transition magnetic moment and the (0–0)/(0–1) bands intensity ratio are calculated. A short review of previous theory of the red and infrared atmospheric oxygen bands and of their enhancement by collisions is presented to analyze and compare the new results. Enhancement of these bands in O₂ collisions with Li₂ and N₂ molecules is calculated by QR method. Diamagnetic species simulate solvent molecules of different optical polarizability. Specific influence of collisions on vibronic bands is stressed. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009     

Synthesis and potentiometric analysis of organophosphorus metal complexones and complexonates based on 2-aminothiazole derivatives

Synthesis conditions of 4-phenyl-2-amidothiazolyl acetate and 2-thiourido-4-diethylphosphothiazole were developed, and the complexation capacity of these compounds in formation of mixed-ligand complexes was studied. The optimal conditions and thermodynamic parameters of the complexation process were determined. The potentiometric method was used to find thermodynamic parameters of the reactions of mixed-ligand complexation with copper(II) and lead(II) ions, the composition of the complexes being formed on the basis of 4-phenyl-2-aminothiazole and its phosphorylated derivatives was determined.     

Complex chromatographic determination of the adulteration of dairy products: A new approach

A new approach to complex chromatographic determination of the adulteration of dairy products was proposed, based on the determination of not only the total fatty acid composition but also the composition of the sterol fraction and the concentration of trans-isomers of fatty acids. Procedures for the chromatographic identification of low-fat dairy products were developed, including the extraction of a water-milkalcohol emulsion with a hexane-ether mixture followed by the chromatographic determination of the sterol fraction and trans-isomers.     

Study of structure and spectral characteristics of the binuclear zinc complex with (<Emphasis Type="Italic">E</Emphasis>)-2-({2-[3-(pyridin-2-yl)-1<Emphasis Type="Italic">H</Emphasis>-1,2,4-triazol-5-yl]phenylimino}methyl)phenol

A study of the structure and spectral properties of the compound (E)-2-({2-[3-(pyridin-2-yl)-1H-1,2,4-triazol-5-yl]phenylimino}methyl)phenol and its binuclear complex with zinc was carried out by the quantum-chemical calculations at a level of density functional theory. Within the framework of the time-dependent density functional theory were calculated electron spectra of both compounds, which gave good agreement with experiment, and was revealed the nature of the absorption bands in the visible and near UV region taking into account the solvent effect. Complete interpretation of the absorption bands in the infrared spectra of the complex and protonated ligand was given, and the frequency shift and changes in the intensities of IR bands of the ligand at the complex formation were analyzed.     

Specific features of the structure of a lanthanum nitrate complex with ethylenediamine

Anhydrous lanthanum nitrate and its complexes with one and two ethylenediamine molecules are calculated by the ab initio B3LYP/LANL2DZ quantum-chemical method. An ethylenediamine molecule is shown to coordinate preferentially through one amino group, and a hydrogen bond is formed between the coordinated amino and nitrato groups. An ethylenediamine complex of lanthanum nitrate is synthesized, and its composition and thermal stability are determined. The IR spectra of the ethylenediamine complex of lanthanum nitrate confirm the presence of the intramolecular hydrogen bond in this complex.     

Arylidenehydroacridines from di(3-arylidene-2-oxocyclohexyl)-methanes

The reaction of di(3-benzylidene-2-oxocyclohexyl)methane and its p-methoxy analog with primary amines results in the formation of derivatives of 4,5-diarylidenehydroacridines, whereas the reaction with o-phenylenediamine is accompanied by the elimination of one arylidene group and gives derivatives of 4-arylidenehydroacridines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1393–1395, October, 1984.     

Addition Polymerization of 5-Ethylidene-2-Norbornene in the Presence of Pd N-Heterocyclic Carbene Complexes

New high-performance catalytic systems based on Pd N-heterocyclic carbene complexes for the selective addition polymerization of 5-ethylidene-2-norbornene (ENB) were proposed. With these catalysts, polymerization can be conducted at unprecedentedly high monomer/catalyst ratio (up to 5 × 10⁵/1) and gives high-molecular-weight soluble polymers with good film-forming properties. Varying the polymerization conditions (reaction temperature, monomer and catalyst concentrations, monomer/Pd ratio) makes it possible to prepare soluble ENB-based addition polymers with specified molecular weights in reasonable yields.