Chemistry Journal of Moldova. General, Industrial and Ecological Chemistry

17-29

Authors: C. P. Bulimaga

The present article is a synthesis analysis of application of chemical methods for the development of technologies of hazardous waste management. Here are offered some technologies of neutralization of the waste containing hexacyanofferates, galvanic wastes and those with contain of vanadium, which are collected at Power Thermoelectric Plants.

38-46

Authors: M.Cocu, J. Gradinaru, M. Revenco, E. Rybak-Akimova, N. Garbalau

This work is devoted to the investigation of the template reactions of organic compounds derived from S-alkylisothiosemicarbazide and β-dicarbonylic compounds (acetyl(benzoyl)acetone, 2,6-diformylpyridine, 2,6-diformyl-4-methylphenol, 1-hydroxy-2-naphthaldehyde, sodium nitromalonic dialdehyde, 1,1,3,3-tetraetoxypropane, 3-ethoxyacroleine) in the presence of 3d-metal ions, determination of the structure and properties of the prepared complexes. There were elaborated original methods for synthesis of open-chain or macrocyclic coordination compounds of nickel(II), copper(II), oxovanadium(IV) and cobalt(II) with N4, N3O and N2O2 tetradentate ligands. Two types of hexaazamacrocyclic systems with trans- and cis- arrangement of thiosemicarbazide fragments have been obtained using template condensation of different precursors. The biostimulative properties (biomass accumulation and increasing of enzymatic activity) of complexes have been established. Some complexes of nickel(II) have been studied as coloring agents for plastics.

55-57

Authors: T. Lupashcu, M. Ciobanu

The adsorption process of ammonia ions and ammonium from aqueous solutions on the intact activated carbon obtained from nutshells through activation with phosphoric acid and oxidized with H2O2 and later impregnated with salt containing Co2+, Ag+, Ni2+, Cu2+, has been investigated. The effi ciency of ammonia ions and ammonium elimination from various water categories, using both activated carbon (the intact CAN-7 and CAN-7 oxidized with H2O2 and impregnated with Co2+, Ag+, Ni2+, Cu2+ ions) has been demonstrated.

65-69

Authors: Pavel Gh.Tatarov, Raisa A. Ivanova, Artur V. Macari

The reducing activity and radical scavenging activity of hydrosoluble antioxidants in food compositions from plums during the storage were evaluated. The speeds of changing the reducing activity and radical scavenging activity were different. It was observed that the reducing activity diminished by 63.2% after 62...105 days of storage. The same modifi cation of radical scavenging activity determined in vitro was discovered after 110...254 days of storage. Shelf-life of plum foods was calculated using Weibull distribution. The functional relationship of failure probabilities between the reducing and radical scavenging capacities have been detected (r2= 0. 94-0.98).

81-85

Authors: Denis Prodius, Valeriu Mereacre, Maria Gdaniec, Sergiu Shova, Yurii A. Simonov, Nicolae Stanica, Ion Geru, Andrea Caneschi, Constantin Turta

A novel hexanuclear iron-calcium-oxo complex has been synthesized and characterized by different physicochemical methods and X-ray single crystal structural analysis: [Fe4Ca2O2(μ2-HCCl2COO)10(μ3-HCCl2COO)2(THF)6]. The molecular structure shows that there are two types of coordination for COO- anions: bidentate and tridentate. The corresponding variable temperature susceptibility measurement shows that in the complex there exists an antiferromagnetic interaction (|J12| = |J34| = -71.86 cm-1). The iron(III) high spin state (5/2) is proved by Mössbauer spectroscopy. High magnetic EPR measurements of 1 indicates the presence of S=0 ground state with low-lying S=1 excited state centred around g = 2.0054 ±0.0001.

95-97

Authors: Viorica Sargarovschi, Eugenia Styngach, Fliur Macaev

New ionic liquids bearing an imidazolium core with a carboxy group have been prepared in an attempt to design new organocatalysts of Biginelli reaction. Trends in the properties of these compounds are discussed. The synthetized compounds represented a novel class of molted salts and may be considered as new organocatalysts for chemical reaction.

101-104

Authors: Alexandra Marchenko, Pavel Kintia, Natalia Mashcenco, Carla Bassarello, Sonia Piacente and Cosimo Pizza

Three phenylethanoid glycosides (1, 2, 3) and one iridoid glycoside (4) were isolated from aerial parts of Veronica chamaedrys L. (Scrophulariaceae) for the fi rst time. On the basis of spectral analysis, the structures of these compounds were determined to be acteoside (3,4-dihydroxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(1→3)-4-Ocaffeoyl- β-D-glucopyranoside) (1), ehrenoside (3,4-dihydroxy-β-phenylethoxy-O-α-L-arabinopyranosyl-(1→2)-α-Lrhamnopyranosyl-( 1→3)-4-O-caffeoyl-β-D-glucopyranoside) (2), chamaedroside (3,4-dihydroxy-β-phenylethoxy-O- α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-α-L-arabinopyranoside) (3) and aucuboside (4).

109-113

Authors: Ion Arsene

The geometry of the H2O2 , O&H , HO&2 , O2 particles and the energy profi les of the initial reactions between them, that are supposed to take place during the process of decomposition of hydrogen peroxide, were studied by ab initio calculations. It was shown that the differences between the energies of reactants and the products of all analysed reaction are positive values and correlate with the experimental data.

119-121

Authors: Diana Dragancea, Vladimir B. Arion, Sergiu Shova

The new ligand, bis(2-hydroxybenzaldehyde)diaminoguanizone (1) has been synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopies. The crystal structure of the compound was determined by X-ray diffraction. The ligand C15H15N5O2·C2H5OH crystallizes in the monoclinic space group P21/c with unit cell parameters a = 8.9102(3), b = 10.0357(3), c = 19.7618(6) Å, β = 98.385(2)°, Z = 4, V = 1748.21(9) Å3, R1 = 0.040. The amino form of the ligand adopts a planar conformation stabilized by two intramolecular hydrogen bonds of the type O–H···N, in which the H atoms of the central amino group are directed to the lone-pair regions of the azomethine nitrogen atoms.