Quantum-chemical study on the tautomerism of primary nitramines: the mechanism of N-nitro-anion protonation excludingaci-form formation

The values of the energy barriers to intramolecular 1,3-H shift reactions, in whichaci-forms of N- and C-nitro-compounds: 1 and are capable of transforming into 2 and , respectively, have been calculated by the semi-empirical AM1 method. The barrier heights (39 and 59.4 kcal/mol) reflect the kinetic stability of both tautomeric forms of the N- and C-nitro-compounds.Ab initio calculations in the 3–21G basis set of the structure and energies of stationary points on the potential energy surface of the system MeN=NO₂ H₃O demonstrated that there exists the principal possibility of the formation of only tautomer 2 (which is more stable than1).Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No 1, pp. 100–104, January, 1993.     

Insights into the mechanism of binding of the gold(III) dithiocarbamate derivatives to cysteine or DNA purine bases

Structural Chemistry - Complexes Au(DMDT)Br2 (DMDT = N,N-dimethyldithiocarbamate), Au(ESDT)Br2 (ESDT = ethylsarcosinedithiocarbamate) and Au(ESDT)Cl2 are likely...     

Excess molar enthalpies of the ternary mixture n-propanol + n-propyl acetate + water at 313.15 K

Journal of Thermal Analysis and Calorimetry - Excess molar enthalpies, H m E , for the ternary mixture n-propanol (n-PrOH) + n-propyl acetate (n-PrOAc) + water...     

The infrared spectra of 2-aminomethylpyridine complexes of metal(II) ions

The infrared spectra (700–150 cm^?1) of twenty-six complexes of 2-aminomethylpyridine (amp) with first transition series metal(II) ions are discussed. The complexes include the tris(amp) complexes [M(amp)₃]²⁺ the bis(amp) compounds M(amp)₂X₂ and the mono(amp) complexes M(amp)X₂. Assignments of the NH₂ rocking modes, v(M-NH₂), v(M-py) and ligand modes are based on the effects of isotopic labelling of the amino group and the effects of substitution of the metal ion and halide. The structural implications of the spectra are discussed.     

Three K[M(salen)(CN)2]-based trinuclear sandwich-like heterobimetallic M(III)–Cu(II) (M = Fe,Cr, Co) complexes: synthesis,crystal structures,and magnetic properties

Transition Metal Chemistry - Three trans-dicyanoiron(III) precursors K[M(salen)(CN)2] (M = Fe, Cr or Co; H2salen = N,N′-bis(salicyl)ethylenediamine) and...     

Gas-tight proton-conducting Nd2 − xCaxZr2O7 − δ (x = 0, 0.05) ceramics

Journal of Solid State Electrochemistry - Gas-tight Nd2 − xCaxZr2O7 − δ (x = 0, 0.05) pyrochlore materials have been prepared via...     

Effects of La-doping on structural,electrical and multiferroic properties of Bi6Fe2Ti3O18 thin films

Journal of Sol-Gel Science and Technology - Bi6Fe2Ti3O18 (BFTO) and La-doped Bi6?xLaxFe2Ti3O18 (BLFT) (x = 0.03; BLFT3, x = 0.06; BLFT6 and 0.09; BLFT9)...     

PROPIOLATE CLUSTER COMPLEXES (Bu4N)2[Mo6X8(OOC–C≡CH)6] (X = Br,I)

Journal of Structural Chemistry - Two new cluster complexes (Bu4N)2[Mo6X8(OOC–C≡CH)6] (1) (X = Br) and (2) (X = I) are synthesized by the reaction of...     

Hydrogen bonds and protonation of carbonyl-containing polynuclear rhodium complexes

According to IR spectroscopy data, the interaction of bi-, tri-, and tetranuclear cyclopentadienylcarbonyl rhodium complexes with rather weak protic acids (phenols, fluoroalcohols) in low-polarity media results in the formation of hydrogen bonds of the OH...O=C type with bridged carbonyl groups. According to¹H NMR data, protonation of these complexes with strong acids (CF₃COOH and HBF₄) occurs at the the Rh-Rh bond to give the symmetrical bridge.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 386–388, February, 1995.This work was carried out with the financial support of the Russian Foundation for Basic Research (Project No. 93-03-0461).     

Electrochemical characterization of non-stoichiometric Cu2S x cathode for lithium batteries

Journal of Solid State Electrochemistry - Electrochemical performances of non-stoichiometric Cu2S x (1.25 ≤ x ≤ 0.625) cathodes prepared by spray...     

Zn salen complex supported on MnCoFe2O4(MCF) magnetic nanoparticles as a catalyst in the synthesis of 3,4-dihydropyrimidin-2 (1H)-ones/thiones (Biginelli-like reaction)

Research on Chemical Intermediates - In the present work, a novel Zn salen complex supported on MnCoFe2O4 magnetic nanoparticles, MnCoFe2O4@SiO2-Pr-NH-SA&Zn (MCF@SiO2-Pr-NH-SA&Zn)...     

Analysis pipeline for air filter gamma-ray spectra from the CTBT verification network

Summary Some environmental xenon sampling like the Automated Radioxenon Sampler-Analyzer (ARSA) and the Swedish Automated Noble Gas Unit (SAUNA), use &bgr;-&ggr; coincidence detectors that are energy dispersive on both the &ggr; and &bgr; axes. Applying conventional region-of-interest (ROI) analysis algorithms to such 3-D spectra is problematic due to spectral interferences in the low-resolution spectra. Deconvolving the 3-D sample spectra into the most probable combination of signals using non-negative least-squares results shows promise to robustly resolve the spectral interferences. This paper describes the multiple isotope component analysis (MICA) algorithm developed for analysis of 3-D &bgr;-&ggr; spectra from xenon sampling and measurement units.     

Microscale investigation of surface contaminations during silicon epitaxial growth

Microchimica Acta - Epitaxial (epi) stacking faults on silicon wafers with <100>- and <111>-orientation were induced by intentional contamination with substances...     

Mg doping improving the cycle stability of LiNi0.5Mn0.5O2 at high voltage

Journal of Solid State Electrochemistry - A series of LiNi0.5-x Mg x Mn0.5O2 (0 ≤ x ≤ 0.1) samples are synthesized by a combination of...     

IMMUNIOMODULATIONG EFFECTS OF THE FUCOIDAN—GALACTOSAN SULFATE（F12） ON MACROPHAGES IN MICE

The immunomodulating effects of F12 on mouse peritoneal macroplhages was intended to be studied with different doses of 20,40,80,and 120mg/Kg.F12 increased peroxidase activity in dexc dependent mammer from 0.02±0.001,to 0.175±0.038,0.211±0.041,0.137±0.045and 0.078±0.036,respectively,increased cytotoxicity from 127.33±22.96 to 162.74±19.53,237.30±25.15,178.62±36.22and 158.66±42.75dpm,respectively,promoted phagocytic activity from 0.03±0.01 to 0.21±0.016,0.43±0.041,0.40±0.032 and 0.30±0.160^b,Furthermore,F12 in a concentration of 15,30,60,120ug/ml enhanced IL-1 production from 0.15±0.02 to 0.20±0.005^b 0.21±0.02,0.22±0.005,0.24±0.002and 0.22±0.02,respectively,Thus F12 can be considered as an effective stimulator of macrophages.     

Improving the combination of cellulose and lignin using xylan as a compatibilizer

Cellulose - Both cellulose and lignin are rich natural resources; however, recombining them to...     

Zinc and aluminium: glutamic acid assisted dual-doped LiMn2O4 spinels via sol–gel method as cathode material for use in lithium rechargeable batteries

Journal of Sol-Gel Science and Technology - LiMn2O4 and LiZnxAlyMn2-x-yO4 (x = 0.07–0.10; y = 0.15–0.18) powders have been synthesized by...     

Rhodium carbonyl complexes of thetrans-[RhCl(CO)(PR3)2] type with pyridylphosphines

Summary Trans-[RhCl(CO)(PR₃)₂] complexes [PR₃=tris-(2-pyridyl)phosphine {P(2-pyl)₃}, phenylbis(2-pyridyl)phosphine {PPh(2-pyl)₂} or tris(3-pyridyl)phosphine {P(3-pyl)₃}] have been synthesized and examined by spectroscopic methods (i.r., u.v.-vis,³¹P{¹H} n.m.r.,¹H n.m.r.). In solution the P(2-pyl)₃ and PPh(2-pyl)₂ complexes exhibit equilibrium between the pentacoordinate state, with one of the phosphine molecules coordinated via nitrogen and phosphorus, and complexes with the phosphine coordinated only through nitrogens.     

Role of the phase transition at GaN QDs formation on (0001)AlN surface by ammonia molecular beam epitaxy

Journal of Thermal Analysis and Calorimetry - We report an original method of GaN/AlN quantum dots (QDs) formation with low density by ammonia MBE on the (0001)AlN...     

Nuclear-physical methods in macro- and microanalytical investigations of contamination with radionuclides at Semipalatinsk Nuclear Test Site

Summary The paper presents a complex of nuclear-physical methods developed in the Institute of Nuclear Physics of Kazakhstan National Nuclear Center for the investigations of the rate, character and peculiarities of contamination with radionuclides of the Semipalatinsk Nuclear Test Site (SNTS). The developed method combines both macroinvestigations (radionuclide analysis, NAA, XRFA, ESR- and NGR-spectroscopy) and microinvestigations (MS, micro-PIXE, electron microscopy). The results of the investigations at the main SNTS test sites “Opytnoye pole' and “Degelen' are presented.