Приказано Природно-математички факултет за наслов
Приказ резултата 176-195 од 269
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Phenolic and flavonoid content and antioxidant evaluation of hawthorn (Crataegus Monogyna Jacq.) fruits and leaves extracts
Considering the facts that phenolic compounds have many pharmacological effects, as well that antioxidant effect of phenolic compounds has been proven in various experimental systems, aim of this research was to determine ... -
PHYSICAL-CHEMICAL CHARACTERIZATION OF PHOSPHATETUNGSTEN BRONZE DOPED WITH IRON FROM HETEROPOLY SALTS AS PRECURSORS
Heteropolyacids, with a general formula ofH3+xAM12O40∙nH2O (x=0-1; A=P, Si, B, As, Ge;M=Mo, W; n=30-6) are of special interest as newmaterials because of their high conductivities. Among them special attention deserves ... -
PHYSICOCHEMICAL INVESTIGATION Zn DOPED PWB
Polyoxometalates (POMs), although having more than a hundred years of history, continue to attract the attention of researchers as catalysts, solid superionic proton conductors at room temperatures, applicable in different ... -
Phytochemical and antioxidant screening of some extracts of Juniperus communis L. and Juniperus oxycedrus L.
(2019-10-25)The content of phytochemicals, total phenolics, total flavonoids and antioxidant potential of extracts of Juniperus communis L. and Juniperus oxycedrus L. berries were determined. Ethanol, ethyl acetate and chloroform were ... -
Plant uptake and soil retention of radionuclides and metals in vineyard environments
In most European countries, each adult citizen drinks on averagemore than 20 L of wine every year. Three popular wine-growing areas (Aleksandrovac, Topola, and Orahovac) in Serbia were studied in order to investigate the ... -
Poly(dimethylsiloxane) modified polymers: Synthesis, structure and physical properties
Poly(dimethylsiloxane)s (PDMS) have one of the lowest values of glass transition temperature among synthetic polymers, and indicate low-temperature flexibility, excellent thermal, thermo-oxidative and ultraviolet stability, ... -
Power Flow in Graded-Index Plastic Optical Fibers
(IEEE, 2019-07-03)A method is proposed for predicting the evolution of the power distribution along graded-index plastic optical fibers. This method is verified against our recently reported measurements. The strong influence of mode coupling ... -
Power flow in multimode step-index plastic photonic crystal fibers
(Elsevier, 2021-08-21)We investigate the state of mode coupling in a multimode step-index plastic photonic crystal fiber (SI PPCF) with a solid-core by solving the time-independent power flow equation. For various arrangements of air-holes, ... -
Power flow in multimode W-type plastic optical fibers with graded index core distribution
(Elsevier, 2021-06-11)A method is proposed for investigation of transmission along a multimode W-type (doubly clad) plastic optical fiber (POF) with graded index (GI) distribution of the core. The multimode W-type GI POF is designed from a ... -
Preparation and characterization of phosphatetungsten bronze doped with iron from heteropoly salts as precursors
Heteropolies of acids and salts heteropolises of acids can also be used as starting materials for the production of tungsten bronzes. These bronzes have a specific structure that results from the collapse of the Kegin anion ... -
Pritisak na rečne obale i njihova transformacija usled izgradnje vikendica i sojenica: slučaj Savskog nasipa (Beograd).
(Asocijacija prostornih planera Srbije, Univerzitet u Beogradu- Geografski fakultet, 2020-11-10)Na prostorima neposredno uz reke, zbog hidroloških, ekoloških i bezbednosnih razloga, kao i zakonskih odredbi, načela i principa planiranja, najčešće nije dozvoljena gradnja. Planska dokumenta ove prostore uglavnom definišu ... -
Procena zdravstvenog rizika izloženosti radonu iz vode u opštini Novo Brdo
Postojanje radona u vodi za pić e dovodi do unutrašnje izloženosti, direktno (kroz procese radioaktivnog raspadanja, ingestije i inhalacije) i indirektno (kada se kombinuju kao deo lanca ishrane). Merenje zastupljenosti ... -
Properties Of Elastomeric Composites Based On Three Network Precursors
(Wiley, 2019-04-10)The powder recycled rubber (PRR) can be used as a filler and a modifier for elastomeric materials and asphalt. Composites based on elastomers and recycled rubber powders are a serious challenge for the environment. The ... -
Quantification of organophosphorus pesticide azamethiphos using electroanalytical approach
In this work, for the first time, we proposed electrochemical behavior and development of analytical procedure for quantification of pesticide azamethiphos, using boron doped diamond (BDD) electrode. It was found that ... -
Quantization of Weights of Neural Networks with Negligible Decreasing of Prediction Accuracy
(Kaunas University of Technology, 2021-09-24)Quantization and compression of neural network parameters using the uniform scalar quantization is carried out in this paper. The attractiveness of the uniform scalar quantizer is reflected in a low complexity and relatively ... -
Radiation stability and thermal behaviour of modified UF resin using biorenewable raw material-furfuryl alcohol
(Elsevier, 2019-06-15)The thermal stability of organic-inorganic nano-composites prepared by a two-stage polymerization of urea-formaldehyde resin (UF) with furfuryl alcohol (FA) and TiO2 before and after irradiation has been researched. The ... -
Radionuclides and Metals in the Parks of the City of Belgrade, Serbia: Spatial Distribution and Health Risk Assessment.
In urban areas, forest patches and parks are usually the places where people spend most of their time outdoors. Due to the poor environmental protection policy and insufficient investment in industry and energy, Serbia is ... -
Radon anomalies as precursors of a recent earthquake: A case study of Kosovska Mitrovica environment
Spike-like peaks in the concentration of radon gas prior to a major earthquake are attributed to release different gases (CO2, CH4, H2S, SO2, H2 suitable for the transport of radon to the earth’s surface) due to pre-seismic ... -
Radon concentration in dwellings in the mining area of “Trepča” complex.
This paper presents the results of radon concentration in ground floor dwellings in the vicinity of the "Trepča" mine. Earlier studies on radon in the area of Kosovska Mitrovica have shown that there are dwellings with ... -
Radon levels and indoor air quality after application of thermal retrofit measures - a case study
This study was conducted toevaluate the influence of thermal retrofit on radon levels in workrooms,and to determine whetherthe radon concentrationin the building changes after the application of retrofit measures.In thefirst ...