Chemistry Journal of Moldova

2018 Volume 13, no.2

EFFECT OF THE NATURE OF SURFACTANT ON THE REACTIVITY OF C,N-DIPHENYLNITRONE TOWARDS ACRYLONITRILE IN DIFFERENT MICROEMULSION SYSTEMS

Author(s):

Kahina Hamza, Abdelkader Touati, Ahmed Ait-Yahia, Michel Baltas, Christiane André Barres, Saâd Moulay


Field: Physical chemistry and chemical physics
Type: Research paper
Issue: 2018 Volume 13, no.2
Pages: 82-88
Keywords: acrylonitrile, cycloaddition, isoxazolidine, microemulsion, nitrone.
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DOI: http://dx.doi.org/10.19261/cjm.2018.522   

Abstract (PDF) 
Graphical Abstract: The present work provides an insight into the effect of the nature of surfactant (cationic, anionic), a component of water- and oil-borne microemulsions, on the reaction rate of 1,3-dipolar cycloaddition of C,N-diphenylnitrone with acrylonitrile. The electrostatically attractive character of the cationic surfactant, would bring the reactants closer to each other; hence, a rate enhancement would ensue, particularly within the water-rich zone. Besides the fact that acrylonitrile played a dual role, as a component of the microemulsion and a dipolarphile in the cycloaddition reaction, made the work-up advantageously sound. Additionally, the increase in reagents molar ratio was found to promote higher reactivity.


 

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METALLURGICAL COKEMAKING WITH THE IMPROVED PHYSICOCHEMICAL PARAMETERS AT AVDEEVKA COKE PLANT

Author(s):

Oleg Zelenskii, Yuriy Vasil’ev, Alexey Sytnik, Natalia Desna, Elena Spirina, Andrey Grigorov


Field: Industrial chemistry
Type: Research paper
Issue: 2018 Volume 13, no.2
Pages: 32-37
Keywords: coal, electrocorundum, carborundum, blend, coke.
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DOI: http://dx.doi.org/10.19261/cjm.2018.516   

Abstract (PDF) 
Graphical Abstract: The article presents the results of studies regarding the improvement of the qualitative characteristics of blast furnace coke obtained from modified coal blend in industrial conditions of Avdeevka Coke Plant. Inorganic corundum powders are applied to modify the coal blend, namely electrocorundum (α-Al2O3) and carborundum (α-SiC). The introduction of a specific quantity (0.25 wt %) of non-clinkering additives allows the modification of the processes that occur when the coal blend is plastic, with consequent improvement in coke strength.


 

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CHEMICAL COMPOSITION AND ANTIMICROBIAL ACTIVITY OF THE LEVISTICUM OFFICINALE W.D.J. KOCH ESSENTIAL OIL

Author(s):

Alexandru Ciocarlan, Ion Dragalin, Aculina Aricu, Lucian Lupascu, Nina Ciocarlan, Violeta Popescu


Field: Natural product chemistry and synthesis
Type: Research paper
Issue: 2018 Volume 13, no.2
Pages: 63-68
Keywords: Levisticum officinale, essential oil, GC-MS analysis, antibacterial activity, antifungal activity.
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DOI: http://dx.doi.org/10.19261/cjm.2018.514 

Abstract (PDF)
Graphical Abstract: The chemical composition of industrially obtained Levisticum officinale W.D.J. Koch (lovage) essential oil of Moldovan origin was analysed by means of chromatographic (GC-MS) and spectral (IR, 1H and 13C NMR) methods. The obtained results show that the main components of L. officinale essential oil are monoterpenic hydrocarbons which make up to 53.50% of the total number of components. L. officinale essential oil is also characterized by a high content of oxygenated monoterpenes (alcohols, cetones and esters), which reaches up to 33.60%. For the first time the presence of 6-butyl-cyclohepta-1,4-diene (0.56%) and 7-formyl-4-methyl-cumarine (0.15%) in lovage essential oil is reported. Antibacterial and antifungal activities of mentioned oil were evaluated in vitro on five strains of microorganisms. It was found that lovage volatile oil (L .officinale) exhibits high antibacterial and antifungal properties in the range of concentrations 0.015-0.030%.


 

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SYNTHESIS AND CRYSTAL STRUCTURE OF BIS(CITRATO)GERMANATE AND STANNATE WITH TRIS(PHENANTHROLINE)NICKEL(II) CATION

Author(s):

Elena Martsinko, Inna Seifullina, Elena Chebanenko, Olha Pirozhok, Viktoriya Dyakonenko, Svitlana Shishkina


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2018 Volume 13, no.2
Pages: 56-62
Keywords: citric acid, 1,10-phenanthroline, germanium(IV), tin(IV), nickel(II) complex.
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DOI: http://dx.doi.org/10.19261/cjm.2018.513  

Abstract (PDF) 
Graphical Abstract: The new complexes [Ni(phen)3][Ge(HCit)2]•2H2O (1), [Ni(phen)3][Sn(HCit)2]•3H2O (2) (where phen is 1,10-phenanthroline, H4Cit is citric acid) were obtained. The identity, composition, and thermal stability of the complexes were established by elemental analysis, thermogravimetry, and IR spectroscopy. According to the X-ray diffraction data, the bis(citrate)germanate / bis(citrate)stannate [Ge/Sn(HCit)2]2- carries out the role of the dianion while two halves of the nickel complexes with phenanthroline [Ni(Phen)3]2+ are cations.


 

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CHEMICAL COMPOSITION AND BIOLOGICAL ACTIVITIES OF SOME MARRUBIUM SPECIES ESSENTIAL OIL: A REVIEW

Author(s):

Benalia Yabrir


Field: Natural product chemistry and synthesis
Type: Review
Issue: 2018 Volume 13, no.2
Pages: 8-23
Keywords: Marrubium specie, essential oil, chemical composition, antioxidant activity, antimicrobial activity.
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DOI: http://dx.doi.org/10.19261/cjm.2018.506  

Abstract (PDF) 
Graphical Abstract: This paper reviews information on essential oil of Marrubium species (except M. vulgare) described until now regarding extraction, chemical composition and biological activities. Marrubium essential oils, although quantitatively poor, are rich in chemical composition. This composition consists especially of sesquiterpenoids and a little amount of monoterpenes. It varies from one species to another, sometimes within same species. Marrubium essential oils exhibit antioxidant and antimicrobial activities. However, because the lack of literature concerning essential oil of these species, further studies are necessary, particularly regarding their activities.


 

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THE EFFECT OF RICE HUSK ON THE PHASE FORMATION AND CEMENT CLINKER PROPERTIES

Author(s):

Lev Chernyak, Liubov Melnyk, Natalia Dorogan


Field: Industrial chemistry
Type: Research paper
Issue: 2018 Volume 13, no.2
Pages: 24-31
Keywords: cement, clinker, rice husk, crystalline phase, property.
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DOI: http://dx.doi.org/10.19261/cjm.2018.502   

Abstract (PDF) 
Graphical Abstract: The features of the cement clinker when rice husk is used are investigated. The dependence of the raw mixture composition on the set product burning characteristics has been analysed using the software “CLINKER”. The mixture compositions have been identified on the basis of the chalk–clay–rice husk system, with the introduction of man-made stock of 6.0–18.0 mass %. The features of the phase composition and the binder properties, by varying the rice husk content, mixture ratio and burning temperature are shown.


 

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SYNTHESIS AND X-RAY CHARACTERISATION OF A NEW MIXED-VALENCE TRINUCLEAR IRON CLUSTER

Author(s):

Olesea Cuzan-Munteanu, Silvia Melnic, Sergiu Shova


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2018 Volume 13, no.2
Pages: 48-55
Keywords: iron cluster, mixed valence, X-ray analysis, µ3-oxo, crystal structure, hydrogen bond.
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DOI: http://dx.doi.org/10.19261/cjm.2018.504

Abstract (PDF) 
Graphical Abstract: This paper reports on the synthesis of a new trinuclear homometalic mixed-valent iron carboxylate cluster with furan-2-carboxylic acid. The complex with the formula [Fe2IIIFeIIO(C4H3OCOO)6(H2O)3]∙0.5CH3CN•2.25H2O was characterized by X-ray analysis that revealed that the compound crystalizes in the triclinic centrosymmetric group P-1, with the following unit cell parameters: a = 10.2758(6)Å, b = 11.5991(9) Å, c = 19.7349(15) Å, α = 105.060(7)°, β =  94.216(6)°, γ = 101.662(6)°.


 

Downloads: 85

MULTICOMPONENT CRYSTALLIZATION OF KETOPROFEN-NICOTINAMIDE FOR IMPROVING THE SOLUBILITY AND DISSOLUTION RATE

Author(s):

Yudi Wicaksono, Dwi Setyawan, Siswandono Siswandono


Field: Physical chemistry and chemical physics
Type: Research paper
Issue: 2018 Volume 13, no.2
Pages: 74-81
Keywords: ketoprofen, multicomponent crystallization, solvent evaporation, solubility, dissolution rate.
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DOI: http://dx.doi.org/10.19261/cjm.2018.493   

Abstract (PDF) 
Graphical Abstract: The study was aimed at increasing solubility and dissolution rate of ketoprofen by using multicomponent crystallization approach with nicotinamide as additional material. The multicomponent crystallization was carried out by solvent evaporation method using 2-propanol as solvent. The solubility and dissolution test showed that the ketoprofen-nicotinamide multicomponent crystal has solubility and dissolution rate significantly higher than the solubility and dissolution rate of the pure ketoprofen.


 

Downloads: 69

NMR STUDIES OF SOME Zn AND Cd COORDINATION COMPOUNDS BEARING 1,2-CICLOHEXANEDIONEDIOXIME

Author(s):

Elena Gorincioi, Eduard Coropceanu


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2018 Volume 13, no.2
Pages: 38-47
Keywords: NMR, zinc, cadmium, oxime, homodinuclear complex, coordination polymer.
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DOI: http://dx.doi.org/10.19261/cjm.2018.368

Abstract (PDF) 
Graphical Abstract: A series of homobi- and polynuclear zinc and cadmium coordination compounds supported by 1,2-cyclohexanedionedioxime and bridging bidentate ligands: 4,4'-bipyridyl, 1,2-bis(4-pyridyl) ethane, 1,3-bis(4-pyridyl) propane and dipiridil sulfide were characterized by the experimental techniques of 1H and 13C NMR spectroscopy. Individual NMR data of compounds are consistent with their assignment as complexes.


 

Downloads: 48

ADSORPTION OF STRONTIUM IONS FROM AQUEOUS SOLUTIONS ON NUT SHELLS ACTIVATED CARBONS

Author(s):

Gheorghe Duca, Mihai Ciobanu, Tudor Lupascu, Igor Povar


Field: Physical chemistry and chemical physics
Type: Research paper
Issue: 2018 Volume 13, no.2
Pages: 69-73
Keywords: activated carbon, adsorption heat, entropy, exothermic process, strontium ion.
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DOI: http://dx.doi.org/10.19261/cjm.2018.494

Abstract (PDF)
Graphical Abstract: The adsorption of strontium ions from aqueous solutions on nut shells activated carbons (samples CAN-7 and CAN-8) at different temperatures has been studied. The isotherm of adsorption of strontium ions from aqueous solutions on activated carbon CAN-7 has two inflection points at relatively small and high equilibrium concentrations. As the temperature increases, the adsorption values decrease, which indicates that the adsorption process is exothermic.


 


Downloads: 58