Facultatea de Chimie şi Tehnologie Chimică / Faculty of Chemistry and Chemical Technology
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Item Efectul antibacterian al unor compuşi organici noi din rândul sulfanilamidelor [Articol](2009) Prisacari, Viorel; Buraciova, Svetlana; Țapcov, Victor; Gulea, AurelianStudiul 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.Item Savant pe linia de avangardă a oenologiei şi biotehnologiei: Boris Găină [Articol](2007) Covaliov, VictorItem Procese tehnologice de obţinere a biogazului în sistemele de epurare anaerobă a apelor reziduale [Articol](2007) Ungureanu, Dumitru; Covaliov, VictorThe 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.Item Возможности применения молдавских природных сорбентов в народном хозяйстве республики [Articol](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.Item Rolul chimiei ecologice în cercetarea poluării şi dezvoltarea durabilă [Articol](2008) Gonța, MariaItem The role of the natural antioxidants in the oxihaemoglobin oxidation and the diminution of nitrite oncentration [Articol](2007) Gonța, MariaThe 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: DFH4Item Removal of Direct Dyes from Textile Wastewater by Means of Combined Methods [Articol](2009) Matveevici, Vera; Duca, Gheorghe; Gonța, Maria; Iambarțev, Viorica; Mocanu, LiliaItem Удаление прямых красителей из текстильных сточных вод комбинированными методами [Articol](2009) Матвеевич, Вера; Дука, Георгий; Гонца, Мария; Ямбранцев, Виорика; Мокану, ЛарисаThe process of removal of textile coloring agents from model solutions by means of consecutive electrochemical and catalytic oxidative treatment in the presence of hydrogen peroxide, and its dependence of the amount of electrochemical coagulant, initial concentration and properties of the coloring agent as well as the iron ions (II) content was discussed in current paper. The obtained results prove that removal of direct colorants through electrical generation of coagulants is more effective and economically sound when carried out from more concentrated model solutions of textile residual waters (the initial concentration should between 150−200 mg/l.) The application of catalytic oxidation procedure can be applied in case of removal of direct colorants of less concentrated solutions (the amount of colorants should not exceed 50 mg/l). From the acquired results was identified that combined methods of electrochemical removal and catalytic oxidation by hydrogen peroxide of direct colorants assure their effective removal from model solutions of residual waters containing up to 200 mg/l of mentioned colorants. The mineralization and residues content was reduced by 97−98%, while the consumption of coagulant was lower by a factor of two in comparison with conventional methods of treatment.Item Assessment of kinetic parameters in the waters of the Nistru course in the section Naslavcea – Dubasari [Articol](2006) Bunduchi, Elena; Duca, Gheorghe; Gladchi, Viorica; Goreaceva, Nelli; Mardari, IgorThe current work represents the results of a monitoring executed on Nistru River waters between October 2003 and September 2005. The water quality was evaluated on the basis of such kinetic indicators as redox state and capacity of inhibition. The obtained results shows that Nistru River water in the segment Naslavcea village – Dubasari barrage are continuously polluted with reducing substances that diminish the H2O2 content, that actually determines the redox state of natural waters and the content of free radicalsItem The study of the buffering capacity of several water objects in the Republic of Moldova [Articol](2009) Lis, Angela; Duca, Gheorghe; Bunduchi, Elena; Gladchi, Viorica; Goreaceva, NelliThe Republic of Moldova is situated among countries with relatively poor water resources, therefore their protection and rational use remains a national problem. Due to its geographic position, the Republic of Moldova is subjected to transboundary pollution. The current work represents the estimation of the buffering capacity on the Dniester River waters and its tributaries between November 2008 and October 2009. Decrease of the buffering capacity in water basins leads to disruption of the normal activity of aquatic biota, by increasing the toxicity in their living environment. On the basis of the results of measurements, suggestions for the improvement of the situation will be made and for enhancing public awareness and public authorities involvement.