Graphical Abstract: No grounded mechanisms for Co-C vitamin B12 coenzyme bond breaking process and subsequent reactions have been found up to now. The influence of the mixing orbitals e.g. Pseudo-Jahn-Teller and similar effects on the reactions paths of bond-cleavage mechanisms of vitamin B12 co-factors must be taken into account. Afterward, the updated mechanisms of vitamin B12 bio-processes can be determined.
Maria Sandu, Anatol Tarita, Raisa Lozan, Natalia Zgircu, Elena Mosanu, Tatiana Goreacioc, Alexandru Zlotea, Anna Comarnitchi, Iulia Sidoren, Sergiu Turcan, Adrian Tarita
Field: Ecological chemistry Type: Research paper Issue: 2016 Volume 11, no.1 Pages: 21-26
Keywords: Lake Beleu, self-purification capacity, nitrification process, BOD5 , COD-Cr. Full Text (PDF):Download
Graphical Abstract: The research results have marked a low value of the self-purification capacity for Beleu Lake water, between 0.12 and 0.19, which is of 1.2-2 times smaller than the one from Prut River (0.25), correlating positively with the values of BOD5, COD-Cr and the time of biochemical oxidation of ammonium ions. The evolution of stage NH4+(NH3) → NO2- in the process of nitrification in lake water in November 2014 takes place about 25 days and the process NO2- → NO3- is more than 35 days, the duration about 2 times higher than in lake water stages from 2015 and 2.8-3.0 times higher than that of the model with water from Prut River.
Graphical Abstract: Aluminium sulphate is one of the most widely used coagulants for water treatment and has been proven to be an effective coagulant for the removal of certain contaminants, turbidity and colour. Aluminium sulphate used during the coagulation process is hydrolyzed in the water, forming polynuclear complexes. Aged aluminium solutions show different coagulation behaviour than that of freshly prepared solutions. Obtained results reveal that using of optimal aging solution of coagulant improves the coagulation process.
Graphical Abstract: Several types of crystals having different color appeared in the synthesis of assembled complex of mixed crystals with three metals. [H2(bpp)][M(NCS)4] changed to 1D chain polymer (M(NCS)2(bpp)) by releasing HNCS from the cation and anion in a reaction vessel.
Ion Bulhac, Alexandra Deseatnic-Ciloci, Paulina Bourosh, Janetta Tiurina, Olga Bologa, Cezara Bivol, Steliana Clapco, Ana Verejan, Svetlana Labliuc, Olga Danilescu
Field: Inorganic and coordination chemistry Type: Research paper Issue: 2016 Volume 11, no.1 Pages: 39-49
Keywords: iron complexes, nitrogen-containing ligands, structure, biological properties. Full Text (PDF):Download
Graphical Abstract: Four coordination compounds of iron(III) with ligands based on hydrazine and sulfadiazine: FeCl3·digsemi·2H2O (I) (digsemi-semicarbazide diacetic acid dihydrazide, [Fe(HL)SO4] (II) (НL - sulfadiazine), [Fe(H2L1)(H2O)2](NO3)3·5H2O (III) (H2L1-2,6-diacetylpyridine bis(nicotinoylhydrazone) and [Fe(H2L2)(H2O)2](NO3)3•1.5H2O (IV) (H2L2 - 2,6-diacetylpyridine bis(isonicotinoylhydrazone) were synthesized. The spectroscopic and structural characterisation as well as their biological, properties are presented.
Graphical Abstract: Synthesis of new drimane and homodrimane lactams, derivatives of octahydro-1H-benzo[d]azepine and octahydro-1H-benzo[c]azepine, from norambreinolide is reported. These compounds were prepared by Beckmann rearrangement of the corresponding ketooximes.
Graphical Abstract: This study describes the synthesis of some novel compounds containing bis-1,3,4-oxadiazole bearing quaternary ammonium salt moieties. The newly synthesized compounds were evaluated for their antibacterial activity against various gram-positive and gram-negative strains of bacteria, and the antifungal activities were tested against three phytopathogenic fungi namely, Fusarium oxysporum, Fusarium commune and Fusarium rodelens.
Graphical Abstract: DFT method has been carried out to study the substitution effects of NO2 group on the electronic (ionization potential, electron affinity, electronegativity, hardness, softness and electrophilicity index) and IR spectral properties of biphenyl and derivative molecules by using the B3LYP functional and the 3-21G basis set, as well as the optimization structure. The calculated values of HOMO and LUMO energies, as well as predicted by ChemBioDraw program 1H and 13C NMR spectra for the studied compounds are in a good agreement with experimental data.
Graphical Abstract: We have synthesized a variety of magnetite nanoparticles which appear to have biogenic signatures and could give insights into how the nanomagnetite particles form in biological systems, and how they are associated with Alzheimer’s disease. We have also synthesized mesoporous magnetite nanoparticles which have potential use in the targeted drug delivery.
Graphical Abstract: Thermodynamic and kinetic mechanisms of forming six semicarbazones have been investigated computationally by DFT B3LYP method. All the reactions proceed via two transitions and include two consecutive steps: bimolecular and unimolecular. The computed transition steps have varying equilibrium constants values, enthalpy of activation and Gibbs energy of activation, depending on the semicarbazone involved.