Facultatea de Chimie şi Tehnologie Chimică / Faculty of Chemistry and Chemical Technology

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Start date: 2000End date: 2009

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    COORDINATION COMPOUNDS OF COPPER(II) WITH BENZOYLHYDRAZONES OF SUBSTITUTED SALICYLALDEHYDES
    (2003) Samusi, Nina; Țapcov, Victor; Kerner, A.
    Benzoylhydrazones of 5-nitro- (H2L1), 3-nitro- (H2L2), 5-chloro- (H2L3), 5-bromo- (H2L4), and 3,5-dibromosalicylaldehydes (H 2L5) react in ethanol with copper acetate to form complexes CuL1-5. In the presence of amines (A = C5H 5N, 3-CH3C5H4N), the above reactions give complexes CuL1-5A·nH2O (n = 0, 1). When cuprous bromide or nitrate and benzoylhydrazone H2L3 were used as starting materials, complexes Cu(HL3)X (X = Br-, NO3-) were isolated. The resulting complexes all are polynuclear structures in which azomethines H2L1-5 behave as tridentate O,N,O-ligands. Thermolysis of the complexes involves the stages of dehydration (70-90°C), deaquation (120-150°C) or deamination (150-180°C), and complete thermal decomposition (350-500°C).
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    COORDINATION COMPOUNDS OF COBALT, NICKEL, AND COPPER WITH ISONITROSOACETONE BENZOYLHYDRAZONE
    (2002) Țapcov, Victor
    Benzoylhydrazine and isonitrosoacetone react in ethanol with cobalt, nickel, and copper halides and acetates to give the coordination compounds MX2(HL)·nH2O, MX2(HL) 2·nH2O, and ML2·nH2O [M = Co, Ni, Cu; X = Cl, Br; HL = C6H5C(O)NHNC(CH 3)CHNOH; n = 1-4]. The same reactions performed in the presence of sodium acetate and pyridine (pH 7-8) yield the complexes MLCl·nH 2O and MPy2LCl·nH2O (n = 1-4). All the complexes have a pseudooctahedral coordination geometry. The hydrazone HL behaves as a tridentate O,N,N-donor ligand. Thermolysis of the substances involves dehydration (70-90°C), deaquation (155-170°C) or deamination (175-195°C), and complete thermal decomposition (285-360°C).
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    EFECTUL ANTIBACTERIAN AL UNOR COMPUŞI ORGANICI NOI DIN RÂNDUL SULFANILAMIDELOR
    (2009) Prisacari, Viorel; Buraciova, Svetlana; Țapcov, Victor; Gulea, Aurelian
    Studiul dat se referă la un grup de substanţe sintetice noi din rândul sulfanilamidelor, care manifestă activitate antibacteriană pronunţată faţă de bacteriile grampozitive şi gramnegative şi, totodată, toxicitate joasă.
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    СВОЙСТВА И ПОРИСТАЯ СТРУКТУРА МОДИФИЦИРОВАННЫХ ОТХОДОВ ВИНОДЕЛЬЧЕСКОЙ ПРОМЫШЛЕННОСТИ
    (2005) Зеленцов, Вячеслав; Дацко, Татьяна; Ковалёв, Виктор
    Two methods of modification of benthonite used in vine clarification have been applied: introduction of Na2S in report 1:10 into benthonite paste followed by pyrolysis at 450oC; electrotreatment of slime suspension in electrochemical cell (in anodic camera and in diaphragmless electrolizer). By means of thermogravimetric analysis some thermal effects attributed to different processes have been observed: removing of water (dehydratation), phase transformations, oxidation of organic compounds, crystallization and destruction of benthonite structure. Adsorption-structural characteristics of initial and modified samples of benthonite slimes have been examined and the mechanism of their change under thermo- and electrotreatment has been discussed.
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    PROCESE TEHNOLOGICE DE OBŢINERE A BIOGAZULUI ÎN SISTEMELE DE EPURARE ANAEROBĂ A APELOR REZIDUALE
    (2007) Ungureanu, Dumitru; Covaliov, Victor
    The continuous development of the civilization stipulates for the increased consumption of the power resources, which determines the search of the new alternative sources of energy. Among the alternative sources of energy a great importance is accorded to the technology of obtaining the biogas. This problem is very actual, especially in the Republic of Moldova, while the natural energetic resources in this country are absent. However our republic possesses the important recovering organic resources which in most cases are not used but are thrown out in the environment together with the sewage.
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    STRATEGIA DE UTILIZARE A DEŞEURILOR GALVANICE ÎN MOLDOVA
    (2001) Șișcovschi, Gheorghe; Orlova, Nadejda; Borodaev, Ruslan
    Problema utilizării deşeurilor galvanice se ridică timp de mulţi ani la diferite niveluri, inclusiv de Guvern (Hot. Nr. 606 din 28 iunie 2000), dar până în prezent în Republica Moldova încă nu există nici un sector tehnologic specializat,cu toate că se cunosc numeroase elaborări brevetate atât la noi, cât şi în ţările CSI sunt destul de multe.
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    ВОЗМОЖНОСТИ ПРИМЕНЕНИЯ МОЛДАВСКИХ ПРИРОДНЫХ СОРБЕНТОВ В НАРОДНОМ ХОЗЯЙСТВЕ РЕСПУБЛИКИ
    (2006) Пушняк, А.; Тутован, Елена; Зеленцов, Вячеслав; Стрелков, Е.; Покатилов, Виктор; Белевский, С.
    In present work the review and characteristics of the most important natural sorbents of Moldavian diatomites, bentonites and trepels are given. The experimental results of investigation of sorptional epuration of residual model solutions from heavy metals and colours by initial and modificated sorbents are discussed. The perspectives of use the natural sorbents of Moldavian in different fields of national economy of Republic are shown.
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    THE ROLE OF THE NATURAL ANTIOXIDANTS IN THE OXIHAEMOGLOBIN OXIDATION AND THE DIMINUTION OF NITRITE CONCENTRATION
    (2007) Gonța, Maria
    The paper includes the study of the inhibition of the process of methemoglobinization at oxidation with nitrites in the presence of sodium dihydroxyfumarate (DFH3 Na) and resveratrol (3,4’,5-trihydroxystilben). The experimental study was carried out by treatment of the erythrocyte mass by hemolysis and exposure to nitrite. The kinetic investigations were carried out in following conditions: [Resv] = (5.10-5 – 1.10-3) mol/l, [DFH3 Na] = 1.10-6 – 5.10-6 mol/l; [HbO2]=1.10-3mol/l; pH 7,1; t = 370 C. The rate of transformation of HbO2 in the presence of resveratrol and DFH3 Na was calculated from kinetic curves of consumption of the substrate and formation of MetHb obtained spectrophotometrically (λmax= 540 nm for HbO2 and λ max =630 for MetHb). It has been found out that the introduction of resveratrol and DFH3 Na in the system HbO2 – NO2-causes the decrease of the auto oxidation factor ϕ DFH3Na approximately by 1.1 – 2.5 times and ϕ resveratrol by 1.1 – 1.7 times. The time of achievement of the maximum rate of oxidation of HbO2 dζ/dτ (where ζ is the rate of transformation of HbO2 in MetHb) increases while the phase of fast oxidation of HbO2 decreases with increase of content of inhibitors. The process of interaction of nitrites with reducers (such as DFH4, DFH3 Na, resveratrol and ( )-catechine) was carried out as well. It has been established that degree of diminishing of the concentration of nitrites in the system RedH2-NO2-decreases as follows: DFH4