Abstract A silica-based inorganic sorbent was synthesized by the thermal decomposition of ammonium heptamolybdate on silica and applied for the preconcentration and simultaneous determination of Cd, Co, Cr, Cu, Fe, Mn, Ni, and Pb in river water samples using a column system with flame atomic absorption spectrometry. Attenuated total reflection-Fourier transformation infrared spectroscopy, scanning electron microscopy, and electron dispersive spectroscopy were used for sorbent characterization. The effects of pH, sample volume, eluent type, eluent concentration, eluent volume, sample flow rate, and matrix ions (Al, Bi, Ca, Mg, and Zn) on the recovery of the metals in model solutions were investigated. The adsorption capacities (µmol g−1) of SiO2-MoO3 were 88.96 (Cd), 169.69 (Co), 153.85 (Cr), 188.88 (Cu), 179.05 (Fe), 163.81 (Mn), 136.31 (Ni), and 38.61 (Pb). The detection limits of the method were 9.09, 10.82, 10.77, 49.57, 31.64, 6.40, 8.86, 19.15 µg L−1 for Cd, Co, Cr, Cu, Fe, Mn, Ni, and Pb, respectively, with a preconcentration factor of 25. The developed method was used for the determination of the target metals in real samples and the recoveries for spiked samples were found to be from 91.2% to 102.9%.

Superkritični fluidi imaju veoma široku mogućnost primene u raznim oblastima. Koriste se u energetskim procesima, kao reakcioni rastvarači, promotori prenosa mase i toplote, separacioni agensi i radni fluidi u procesima sa biogorivom. Iako je ugljen-dioksid još uvek jedan od najčešće korišćenih superkritičnih fluida, propan i fluorovano-hlorovani fluidi se takođe koriste. Postoje brojni slučajevi gde su se kao superkritični fluidi koristili metanol, smeša metanola i sirćetne kiseline, metil – acetat, dimetilkarbonat. Procesi dekofeinizacije čaja i kafe, ekstrakcije hmelja i uklanjanja pesticida iz pirinča primenom superkritičnih fluida zastupljeni su već duže vremena na industrijskom nivou. Glavni cilj primene superkritičnih fluida je još uvek ekstrakcija prirodnih proizvoda radi dobijanja sastojaka hrane, nutraceutikalija i fitofarmaceutikalija. Superkritični procesi su ispitivani i radi dekontaminacije zemljišta, uklanjanja zaostalih rastvarača iz farmaceutskih proizvoda, ekstrakcije zapaljivih jedinjenja iz elektronskog otpada. Povećan je i interes za impregnaciju zasnovanu na primeni superkritičnih fluida kao i korišćenje superkritičnih fluida za bojenje vlakana i tekstila. Dobijanje finih čestica mikronske i submikronske veličine uglavnom za farmaceutske proizvode je još jedna u nizu primena superkritičnih fluida. Na ovaj način se mogu dobiti novi proizvodi koje je nemoguće dobiti klasičnim postupcima. Tehnologija superkritičnih fluida i danas se suočava sa veoma rasprostranjenim mišljenjem da su ovi procesi veoma skupi zbog velikih investicionih ulaganja i da su usled toga ograničeni isključivo na dobijanje izuzetno vrednih proizvoda. Procena troškova za postrojenja različitih veličina i za različite primene je takođe analizirana u okviru rada.

This study evaluates the genotoxic potential of two Ru(III) complexes with thiosemicarbazone based ligands. The complexes were tested for in vitro protective effect on chromosome aberrations in peripheral human lymphocytes using the cytokinesis block micronucleus (CBMN) assay at concentrations 1.5; 3.7 and 7.4 μg/mL. The cell culture treated with the tested complexes, at 3.7 μg/mL concentration, decreased a frequency of micronucleus for 37% and 32%, when compared with the control cell cultures. At concentration of 7.4 (1.5) μg/mL of this complexes exhibited slightly lower effect of micronucleus for 30% (35%) and 27% (29%), when compared with the control cell cultures.

In this study, novel hexa coordinated ruthenium(III) complex of the type Na[RuCl2L2)] (where L = monobasic bidentate Schiff base derived from the condensation of 5-nitrosalicyladehyde with aniline) has been synthesized and characterized by electrospray ionization time-of-flight mass spectrometry, infrared spectroscopy and ultraviolet/visible spectrophotometry. Schiff base N-phenyl-5-nitrosalicylideneimine is coordinated to the ruthenium via imine nitrogen and phenolic oxygen. Mass spectra showed molecular ion (M-) at m/z 653.9641 which corresponds to [C26H18Cl2N4O6Ru]. The in vitro antimicrobial properties of the Schiff base and the complex were tested by micro-dilution technique and agar plate assay for determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The compounds showed a higher antibacterial activity against tested Gram-positive bacteria (Staphylococcus aureus ATCC 33591 and ATCC 29213), whereas against the Gram-negative bacteria (Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603) were ineffective. The genotoxic effects of Ru(III) complex were investigated using the Cytokinesis Block Micronucleus (CBMN) assay in human lymphocytes cultures. The cell culture treated with the complex at a concentration of 3.7 μg/mL exhibit the most prominent effect of decreasing the frequency of micronucleus for 44%, while at the concentrations of 1.5 and 7.4 μg/mL effect is slightly lower (40%), compared to the control cell culture.

This study evaluates the genotoxic potential of two Ru(III) complexes with thiosemicarbazone based ligands. The complexes were tested for in vitro protective effect on chromosome aberrations in peripheral human lymphocytes using the cytokinesis block micronucleus (CBMN) assay at concentrations 1.5; 3.7 and 7.4 μg/mL. The cell culture treated with the tested complexes, at 3.7 μg/mL concentration, decreased a frequency of micronucleus for 37% and 32%, when compared with the control cell cultures. At concentration of 7.4 (1.5) μg/mL of this complexes exhibited slightly lower effect of micronucleus for 30% (35%) and 27% (29%), when compared with the control cell cultures.

Abstract A silica-based inorganic sorbent was synthesized by the thermal decomposition of ammonium heptamolybdate on silica and applied for the preconcentration and simultaneous determination of Cd, Co, Cr, Cu, Fe, Mn, Ni, and Pb in river water samples using a column system with flame atomic absorption spectrometry. Attenuated total reflection-Fourier transformation infrared spectroscopy, scanning electron microscopy, and electron dispersive spectroscopy were used for sorbent characterization. The effects of pH, sample volume, eluent type, eluent concentration, eluent volume, sample flow rate, and matrix ions (Al, Bi, Ca, Mg, and Zn) on the recovery of the metals in model solutions were investigated. The adsorption capacities (µmol g−1) of SiO2-MoO3 were 88.96 (Cd), 169.69 (Co), 153.85 (Cr), 188.88 (Cu), 179.05 (Fe), 163.81 (Mn), 136.31 (Ni), and 38.61 (Pb). The detection limits of the method were 9.09, 10.82, 10.77, 49.57, 31.64, 6.40, 8.86, 19.15 µg L−1 for Cd, Co, Cr, Cu, Fe, Mn, Ni, and Pb, respectively, with a preconcentration factor of 25. The developed method was used for the determination of the target metals in real samples and the recoveries for spiked samples were found to be from 91.2% to 102.9%.

Major energy provider (80%) for current economy and lifestyle are fossil fuels. Transport sector, a major consumer of petroleum fuels (diesel, gasoline, liquid petroleum gas and compressed natural gas, is likely to suffer badly because oil re-serves are decreasing, and therefore, there is a continuous rise of crude oil prices. Fossil fuels emit greenhouse gases (CO2, CH4 and CO) resulting in global warming and pollution. Intensive research is going on to generate clean and sustainable energy sources from renewable carbon resources. Biofuels represent ecofriendly, biodegradable, sustainable, cost competitive and promising alternative energy source for fossil fuels. The primary motivation for the development of biofuels is decreasing dependence from fossil fuels import in some countries and it is not re-duce CO2 emissions. This paper reviews methods for obtain biofuels from lignocellulosic feedstock and technologies.

Many industries generate phenolic wastewater of acidic nature. Neutralization with sodium hydroxide generates the phenolic wastewater with high total dissolved solids. Both phenol and ionic concentration of total dissolved solids are inhibitor to biological treatment processes. In this paper described a process of biological treatment of waste water with particular reference to the treatment of waste water with a high concentration of phenol, and the total dissolved solids in a reactor with a moving-bed biofilm. The efficiency of the bioreactor with a moving-bed biofilm for removal phenolic solution with a high chemical oxygen consumption is analyzed. It is also studied the efficiency of removing phenol and dissolved particles, depending on the hydraulic retention time.

In this paper, supercritical extraction of hyssop (Hyssopus officinalis L.) is performed by using carbon dioxide as extractant. Effect of pressure (80, 100 and 150 bar) on the yield of total extract at a temperature 313 K, flow 0.00323 kg/min and the average diameter of particles 0.49 mm is investigated. For modeling of extraction system hyssop – supercritical CO2, Naik's model is applied, where in the total yield of extract is determined. On the basis of the value of the correlation coefficient |r| (0.976 – 0.992), it was concluded that a very strong correlation was obtained between reciprocal values of the total extract yield and extraction time (1/y i 1/t), so it can be concluded that Naik's model can succesfully be applied for determining yield of total extract.

Two different methods for deriving the density and isobaric heat capacity of liquids in the subcritical pressure range, from the speed of sound, are recommended. In each method, corresponding set of differential equations relating these properties is solved as the initial boundary value problem (IBVP). The initial values are specified at the lowest pressure of the range and the boundary values along the saturation line. In the first method, numerical integration is performed along the paths connecting the Chebyshev points of the second kind between the minimum and maximum temperature at each pressure. In the second method, numerical integration is performed along the isotherms distributed in the same way, with the temperature range being extended to the saturation line after each integration step. The methods are tested with the following substances: Ar, N2, CO2, and CH4. The results obtained for the density and isobaric heat capacity have the average absolute deviation from the reference data of 0.0005% and 0.0219%, respectively. These results served as the initial values for deriving the same properties in the transcritical pressure range up to the pressure approximately twice as large as the critical pressure. The results obtained in this pressure range have respective deviations of 0.0019% and 0.1303%.

Glavni izvor energije koja se koristi radi zadovoljenja životnih i ekonomskih potreba su fosilna goriva. Sektor transporta kao glavni potrošač fosilnih goriva (dizela, benzina, tečnog naftnog gasa i komprimovanog prirodnog gasa) će biti u problemu zbog stalnog smanjenja rezervi nafte što vodi ka kontinualnom porastu cena sirove nafte. Fosilna goriva emituju gasove koji izazivaju efekat staklene bašte (CO2, CH4 i CO) što za posledicu ima globalno zagrevanje i zagađenje. Da bi se ovaj problem preduprevio vrše se intenzivna istraživanja u cilju dobijanja čiste i održive energije iz obnovljivih izvora ugljenika. Biogoriva predstavljaju ekološka, biodegradabilna, održiva, ekonomski konkurentna i obećavajuća alternativna goriva. Primarni motiv za razvoj biogoriva je manja zavisnost pojedinih država od fosilnih tečnih goriva a ne smanjenje CO2 emisije. U ovom radu daće se pregled metoda za njihovo dobijanje iz lignoceluloznih sirovina kao i trenutno raspoložive tehnologije. Ključne reči: biogorivo; lignocelulozne sirovine; metode; energetski izvori