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With the growth of the industrial world and the rise of anthropogenic activities, environmental challenges have also increased. Wastewater, especially from industrial sources can contain a wide variety of heavy metals [1]. The presence of heavy metals in water resources is a cause for concern due to their toxicity and tendency to bioaccumulation, which leads to significant problems for the environment as well as for animals and humans [2]. There are various conventional treatment technologies that are used for the removal of heavy metals from wastewater such as reverse osmosis, electrodialysis, ultrafiltration, industrial ion exchange process, and chemical precipitation. These techniques have some drawbacks such a being expensive due to high reagent and energy requirements, incomplete metal removal at low concentrations of heavy metals and generation of sludge [1]. Therefore, biosorption has been the subject of research by scientists for almost 70 years in order to find efficient, effective, and low-cost biomaterials for wastewater treatment [3]. In this study, a sunflower husk treated with 1% hydrochloric acid was used to evaluate removal efficiency for Ni from real wastewater samples, as well as to estimate the adsorption capacity as a function of contact time between the heavy metal ions such as Cd in the aqueous solution and the sunflower husk as a biosorbent. Two techniques were used for quantitative analysis, Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) as a standard reference method and laser-induced plasma spectroscopy (LIBS) as an innovative non-standard analytical method. What makes the LIBS superior from the other standard optical techniques is that it allows fast multi-elemental analysis without prior sample preparation, leads to minimal sample damage, and is considered almost non-destructive, this method is also by the principles of green analytical chemistry, which means that it does not use toxic reagents and therefore no chemica

Taking into account that powder paprika is among spices that are often subjected to adulteration, the aim of this work was the analysis of twelve different branded powder paprika collected from Serbian markets. The total content of ash and sand was determined, and results have shown that values ranged from 5.40 to 7.80% and from 0.77 to 2.23%, respectively. The inductively coupled plasma optical emission spectrometry method was used for the quantification of 16 elements (Cd, Fe, Ni, Pb, Be, Zn, Cu, Mo, Ti, Sr, Ca, Al, B, Cr, Mg and Mn). Among all determined elements, the most abundant was Ca, followed by Mg and Fe. UV spectroscopy was used as a screening method to determine the adulteration level with Sudan I dye of spice paprika powders. It was found that none of the investigated samples contain Sudan I dye. Furthermore, multivariate classifications models were created for discrimination based on adulterant and powder paprika content in sample mixtures.

Surface changes created by interaction of transversely excited atmospheric carbon dioxide (TEA CO2) laser with titanium target/implant in nitrogen and carbon dioxide gas were studied. TEA CO2 laser operated at 10.6 mu m, pulse length of 100 ns and fluence of similar to 17 J/cm(2) which was sufficient for inducing surface modifications. Induced changes depend on the gas used. In both gases the grain structure was produced (central irradiated zone) but its forms were diverse, (N-2: irregular shape; CO2: hill-like forms). Hydrodynamic features at peripheral zone, like resolidified droplets, were recorded only in CO2 gas. Elemental analysis of the titanium target surface indicated that under a nitrogen atmosphere surface nitridation occurred. In addition, irradiation in both gases was followed by appearance of plasma in front of the target. The existence of plasma indicates relatively high temperatures created above the target surface offering a sterilizing effect.

Surface changes created by interaction of transversely excited atmospheric carbon dioxide (TEA CO2) laser with titanium target/implant in nitrogen and carbon dioxide gas were studied. TEA CO2 laser operated at 10.6 mu m, pulse length of 100 ns and fluence of similar to 17 J/cm(2) which was sufficient for inducing surface modifications. Induced changes depend on the gas used. In both gases the grain structure was produced (central irradiated zone) but its forms were diverse, (N-2: irregular shape; CO2: hill-like forms). Hydrodynamic features at peripheral zone, like resolidified droplets, were recorded only in CO2 gas. Elemental analysis of the titanium target surface indicated that under a nitrogen atmosphere surface nitridation occurred. In addition, irradiation in both gases was followed by appearance of plasma in front of the target. The existence of plasma indicates relatively high temperatures created above the target surface offering a sterilizing effect.

Group of higher plants, known as desiccation tolerant or resurrection plants, possess uniquely effective mechanism to withstand extreme dehydration and rapid rehydration of vegetative tissues without cell damage. Resurrection plants survive the loss of most of their tissues water content until a quiescent stage is achieved. Upon watering, the plants revive and are restored to their former state within 24h. In order to cope with desiccation, resurrection plants have to overcome a number of stresses, among them the most critical being oxidative stress. In our previous investigations, we have shown that during the rehydration process in A. ceterach, •OH radicals are produced. In vivo productions of free radicals remain unexplained and difficult for examination. By application of specific fluorescence probe for detection of hydroxyl radical APF (3’-(p-aminophenyl) fluorescein) it is possible to get insight into processes occurring in fronds during the dehydration process. In reaction of hydroxyl radical with APF, fluorescent product emerges. Examination under fluorescence microscope and image capturing in time intervals provides determination of hydroxyl radical production in different plant tissues. Through image analysis based on multivariate techniques, it is possible to simultaneously distinguish plant tissues according to its morphological and physiological properties.

In 1989 Erwinia amylovora was confirmed to be a pathogen of pear and quince in Serbia. Subsequently, apple, firethorn, hawthorn, Mespilus spp., Cotoneaster horisontalis and Cheanomeles spp. were confirmed as hosts of the pathogen. During the summer 2005, fire blight symptoms were observed on Sorbus spp. for the first time in the south-eastern Serbia, near Nis. Disease symptoms included leaf and shoot blight and cankers with purple-brown colouration of necrotic tissue on mature branches. The diseased tissue was macerated and the suspension was streaked on nutrient sucrose agar (NAS) and King's medium B. Typical light grey, levan-positive colonies developed on NAS medium after two day incubation at 25°C. Colonies on King's medium B were white and nonfluorescent. The results of physiological and biochemical tests of the bacterium were as follows: gram negative, oxidative and fermentative metabolism of glucose; oxidase negative, gelatin hydrolysis positive, aesculin hydrolysis negative and acid produced from most carbon sources. In pathogenicity tests, all isolates induced HR in tobacco leaves and necrosis on artificially inoculated pear fruits followed by appearence of bacterial ooze. After inoculation of petioles and shoots of the host plant (Sorbus spp.) initial symptoms were dark green, watersoaked, eliptical spots on inoculated tissues. Leaf and shoot blight resembling the natural infection appeared five to six days after inoculation. The investigated strains reacted positively with antisera specific to E. amylovora in DASI ELISA test. Identity of isolated strains also was confirmed by polymerase chain reaction (PCR). According to the biochemical and physiological characteristics, pathogenicity tests, results of PCR analyses and ELISA test, strains isolated from Sorbus spp. plants were identified as E. amylovora. This is the first report of E. amylovora on Sorbus spp. plants in Serbia.