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During the first few days after explosion, Type II supernovae (SNe) are dominated by relatively simple physics. Theoretical predictions regarding early-time SN light curves in the ultraviolet (UV) and optical bands are thus quite robust. We present, for the first time, a sample of 57 R-band SN II light curves that are well-monitored during their rise, with detections during the first 10 days after discovery, and a well-constrained time of explosion to within 1-3 days. We show that the energy per unit mass (E/M) can be deduced to roughly a factor of five by comparing early-time optical data to the 2011 model of Rabinak & Waxman, while the progenitor radius cannot be determined based on R-band data alone. We find that SN II explosion energies span a range of E/M = (0.2-20) ×1051 erg/(10 ), and have a mean energy per unit mass of erg/(10 ), corrected for Malmquist bias. Assuming a small spread in progenitor masses, this indicates a large intrinsic diversity in explosion energy. Moreover, E/M is positively correlated with the amount of 56Ni produced in the explosion, as predicted by some recent models of core-collapse SNe. We further present several empirical correlations. The peak magnitude is correlated with the decline rate (), the decline rate is weakly correlated with the rise time, and the rise time is not significantly correlated with the peak magnitude. Faster declining SNe are more luminous and have longer rise times. This limits the possible power sources for such events.

We present ultraviolet (UV) observations of six nearby Type Ia supernovae (SNe Ia) obtained with the Hubble Space Telescope, three of which were also observed in the near-IR (NIR) with Wide-Field Camera 3. UV observations with the Swift satellite, as well as ground-based optical and NIR data provide complementary information. The combined data set covers the wavelength range 0.2-2 μm. By also including archival data of SN 2014J, we analyse a sample spanning observed colour excesses up to E(B - V) = 1.4 mag. We study the wavelength-dependent extinction of each individual SN and find a diversity of reddening laws when characterized by the total-to-selective extinction RV. In particular, we note that for the two SNe with E(B - V) ≳ 1 mag, for which the colour excess is dominated by dust extinction, we find RV = 1.4 ± 0.1 and RV = 2.8 ± 0.1. Adding UV photometry reduces the uncertainty of fitted RV by ~50 per cent allowing us to also measure RV of individual low-extinction objects which point to a similar diversity, currently not accounted for in the analyses when SNe Ia are used for studying the expansion history of the Universe.

The meetings industry is one of the fastest developing segments of the tourism market and inevitable component of performances achieved on the destination level. The Covid-19 crisis has transformed the way this industry operates, leading to new ways of holding meetings. The aim of the paper is to analyze the effect of the Covid-19 pandemic on meetings' industry performances of the Republic of Serbia, as well as its post-covid recovery in this country. The results of the analysis showed a decrease in the meetings held in pandemic years, but also a recovery in 2022. Results also showed that holding virtual meetings became the new normal. Moreover, online meetings were the foundation for developing novel approaches for the new future of the meetings industry and special event management.

In this work, TiO2-based composite photocatalysts were synthesized for the photoreduction of Cr(VI) by deposition of CdS and/or Cu nanoparticles. Oak leaf extract was used as a reducing agent for the synthesis of Cu nanoparticles. Although the deposited amount of Cu was small (~ 1.1 wt%), it resulted in a shift of the absorption edge to the visible region and a significantly higher efficiency compared to TiO2. Deposition of ~ 3 wt% CdS resulted also in a higher activity under the visible light compared to TiO2, but lower compared to Cu-TiO2. The best results were obtained with the ternary photocatalyst, probably due to the formation of a z-scheme in which the deposited Cu acts as a mediator for electron transfer between CdS and TiO2. The addition of citric acid as a hole "scavenger" allowed a further increase in activity, even in the case of TiO2.

The surfaces of natural (NZ) and zeolite/iron oxyhydroxide composite (ZFe) samples were analysed by means of inverse gas chromatography (IGC) using the adsorption data of organic non-polar and polar probes, in the infinite and finite-dilution regimes, in the temperature range 483–513 K. The dispersive components of the free energy of adsorption, γS, determined by the Gray method, decreased with increasing temperature for both zeolites. The specific interactions were characterised by the specific free adsorption energy change, ΔGa S, the specific enthalpy change of adsorption, ΔHa S, as well as the donor and acceptor interaction parameters (KA, KD) and the basic character of the NZ and ZFe was evidenced. The adsorption isotherms of n-hexane, benzene, chloroform and tetrahydrofuran (THF) were determined under finite surface coverage and used to estimate the specific surface area and the adsorption energy distribution. The adsorption capacity of the ZFe was higher than for NZ for all the investigated adsorbates. The specific surface areas and pore size distributions were also determined using nitrogen adsorption–desorption isotherms, i.e., the BET method. It was observed that the nature of the adsorbate and the properties of the solid surface of the initial and modified samples governed the uptake of adsorbates.

The sorption of [Pb.sup.2+], [Cd.sup.2+], and [Sr.sup.2+] ions from aqueous solutions by carbonate-substituted calcium hydroxyapatite (HAP) obtained by the hydrothermal decomposition of urea and calcium-ethylenediaminetetraacetic acid chelates was investigated. The shift of the point of zero charge ([pH.sub.pzc]) of HAP toward lower pH values in solutions of [Pb.sup.2+] and [Cd.sup.2+] ions, which was more pronounced for [Pb.sup.2+] ions than for [Cd.sup.2+] ions, indicates that specific adsorption of these cations on HAP had occurred. There was no shift of the [pH.sub.pzc] in the solution containing [Sr.sup.2+] ions, suggesting that specific adsorption of this cation on HAP had not occurred. The sorption isotherms suggest that the sequence of the efficiency of sorption by HAP is [Pb.sup.2+] > [Cd.sup.2+] > [Sr.sup.2+]. Ion exchange is the main mechanism of removal of [Sr.sup.2+] ions from aqueous solution by apatite, whereas during the sorption of [Cd.sup.2+] ions, this mechanism occurs simultaneously with the process of specific adsorption. The interaction of the apatite with [Pb.sup.2+] ions includes the previously mentioned mechanisms and dissolution of the apatite, followed by the precipitation of lead hydroxyapatite. CE Database subject headings: Sorption; Ion exchange; Metals; Water quality.

Social crises in various forms have become a modern day challenge. Dealing with its consequences can best be seen in the political, economic and security sectors. In earlier periods, public relations was considered to be the most important for large corporations in their positioning on the market. However , today, when the world is facing a small and intertwining crisis (World Economic Crisis, Migrant Crisis, Brexit, Covid 19 Crisis, and the last Ukrain-Russian Crisis) it is clear that governments and state bodies must be stable carriers of crisis response, precisely because the institutions are the ones that guarantee stability of the state. In cases of inadequate response to the crisis situation, the trust of the citizens in the institution that is the bearer of the response to the crisis is shaken, which further reflects on the reputation of the institution itself, and then od the stability of the state. Therefore , every state body must be ready for decision- making in crisis situations. This text will present the recommendations that the crisis team must adopt in order to adequately respond to crisis situation. In addition to the above, the example of the reaction of the Government of the Republic of Serbia to the crisis caused by the COVID 19 virus will be analyzed, in order to position further desirable behavior of the institutions in times of crisis.

Every generation of people has needs, incentives, desires, intentions, attitudes and values that make it distinguishable, specific and unique. Generation Z is entering the labour market and beginning its search for an ideal employer in order to obtain outstanding experience and optimal employee value proposition. Members of Generation Z have specific traits and characteristics that set them apart from other generations. In order to build a brand as a successful and desirable employer in digital economy, one should take into account these specific traits and characteristics in order to attract and retain members of Generation Z in the long term. This paper points out the key factors of employer branding and employee value proposition that influence Generation Z's decision-making regarding employment. The results of an empirical research, which included 339 members of Generation Z from the Republic of Serbia, indicated the following three key factors that influence their choice of an employer: the opportunity for career advancement, a pleasant and interesting work environment, and the opportunity for personal development (acquiring new knowledge and skills). The conducted research provides important information on the basis of which employers can better conceptualize value proposition for members of Generation Z and establish their branding of a desired employer.

The Covid-19 pandemic has brought numerous economic challenges to countries around the world. The specificities of certain economy sectors determined the character and intensity of the impact of this health crisis on their results. The purpose of the paper is to analyse the impact that the Covid-19 pandemic has had on the economic results of agriculture in the European Union countries. Comparative analysis and cluster analysis are used in the research. The general conclusion of the paper is that the Covid-19 pandemic did not change the economic importance and role of agriculture in the individual European Union countries. In addition, the European Union countries differ significantly according to the impact of the Covid-19 pandemic on the contribution of agriculture to gross domestic product, while a significant difference between the countries has not been determined according to the impact of the pandemic on the contribution of agriculture to employment.

The paper points out the leading role of the HR department in crisis situations, with special emphasis on the crisis caused by the COVID-19 pandemic, which affected the whole world in early 2020. Regardless of the intensity and form in which they occur, crises threaten the functioning and survival of organizations. The HR department is an important factor in the successful functioning of organizations and, in a period of crisis, this department takes a leading role in the process of crisis management and subsequent recovery. During COVID-19 pandemic, the HR department of every organization had to confront new challenges in order to protect the health of employees, while ensuring the normal functioning of organizations. In order to find out how this department dealt with crisis that occurred, empirical research with a specially designed questionnaire was conducted and filled in by 108 respondents from Serbia, Bosnia and Herzegovina, and Croatia in 2020. The research results showed that HR department has taken a leading role in preserving the health and safety of employees, as well as in the process of adapting organizations to function in crisis conditions. According to results, the key activities carried out by the HR department in organizations are work from home (wherever the nature of the work allowed), flexible working hours, reorganization of the working space to achieve the required physical distance between employees, improved hygiene measures, etc. In addition, the research results showed that, during the global COVID-19 pandemic, the HR departments took an active role in providing psychological assistance to employees to adapt to new conditions and ways of working.

Every organization strives to have productive, creative, responsible employees, who constantly seek to acquire new knowledge and skills, who are motivated, loyal and engaged, and psycho-physically healthy. However, modern and dynamic business conditions, constantly growing demands and needs of consumers, setting new goals and tasks, increasing the level of responsibility and standards, and often setting expectations from employees too high are just some of the many pressures and sources of stress to which employees are permanently exposed in their workplace. Caring about employees, and safety and health protection at work is one of the important activities of the business function of human resource management. The priority task of experts in this field is to act preventively against stressors by creating various methods and techniques for their efficient and effective management. One of the techniques that is becoming increasingly popular in socially responsible organizations, are wellness programmes. By organizing and implementing these programmes, the management of the organization shows that it cares and acts preventively to maintain the safety and protection of the health of its employees, and the employees themselves acquire new knowledge and healthy life habits through these programmes. This paper points out the importance and role of wellness programmes, as important activities of strategic human resource management of modern organizations, which occupies a significant position in the protection and prevention of employee health. Also, the paper outlines all the important elements that management should keep in mind when designing and implementing wellness programmes in order for them to adequately influence the improvement of physical and mental health of employees.

Revenues generated by football clubs belonging to one of the socalled "The Big Five" leagues (England, Germany, Spain, Italy and France) give a strong argument by claiming that modern football has become a very organized, but also profitable business. In the football clubs of the mentioned European countries, the most famous players of today are "super heroes" and they are the reason why massive numbers of football fans visit football stadiums. All players, who today identify themselves as elite athletes, were at the beginning of their sports careers merely talented individuals with more or less pronounced psycho-physical predispositions for playing sports. This paper will present the basic characteristics of the profession of professional scouts as one of the key persons in recognizing talents and their transformation into top athletes. Also, the paper emphasizes the necessary skills that these sports experts should possess, but also points out the importance of decisionmaking in terms of often difficult and complicated decisions in the process of identifying talented individuals in sports.

Introduction. Fat embolism refers to the presence of fat globules in the lung parenchyma and its peripheral circulation. Obstruction of the lung vessels by fat emboli can lead to acute cor pulmonale when the compensatory capabilities of the pulmonary vasculature are exceeded. Case report. We presented a case of a 78-year old man who suffered a dissection of abdominal aortic aneurysm. Urgent surgical procedure was performed and aneurysm replaced with aortobifemoral bypass grafting using a Dacron graft. Despite the procedure the patient died the following day. The autopsy revealed that the cause of death was hypovolemic shock. There were no bone fractures (also no fractures of ribs and sternum from cardiopulmonary resuscitation) or injuries of the subcutaneous fat tissue or other organs (besides those from the surgery). However, additional autopsy findings included fatty liver change, small liver hemorrhages (confirmed microscopically), as well as a presence of fat droplets in the hepatic veins, as well as in the pulmonary vessels, i.e. pulmonary fat embolism [confirmed with hematoxylin/ eosin (H/E), and Sudan III staining], which could be the contributing cause of death. Conclusion. The presented case indicates that pulmonary (or even systemic) fat embolism should be considered as the possible iatrogenic cause of unexpected and unexplained death in the cases where elective surgical procedures were performed in patients with fatty liver change. Pathologists must be aware of this possibility, since it is not easily recognized on routine H/E staining, and some of the special staining technique should be applied.

The sorption of Pb2+, Cd2+, and Sr2+ ions from aqueous solutions by carbonate-substituted calcium hydroxyapatite (HAP) obtained by the hydrothermal decomposition of urea and calcium–ethylenediaminetetraacetic acid chelates was investigated. The shift of the point of zero charge (pHpzc) of HAP toward lower pH values in solutions of Pb2+ and Cd2+ ions, which was more pronounced for Pb2+ ions than for Cd2+ ions, indicates that specific adsorption of these cations on HAP had occurred. There was no shift of the pHpzc in the solution containing Sr2+ ions, suggesting that specific adsorption of this cation on HAP had not occurred. The sorption isotherms suggest that the sequence of the efficiency of sorption by HAP is Pb2+>Cd2+>Sr2+. Ion exchange is the main mechanism of removal of Sr2+ ions from aqueous solution by apatite, whereas during the sorption of Cd2+ ions, this mechanism occurs simultaneously with the process of specific adsorption. The interaction of the apatite with Pb2+ ions includes the previously mentioned mechanisms and dissolution of the apatite, followed by the precipitation of lead hydroxyapatite. [ABSTRACT FROM AUTHOR]

In order to improve the mechanical properties of paper, 1, 3 and 5 wt.% of sepiolite were dispersed in a poly(vinyl butyral) (PVB) matrix and coated onto the surface of schrenz (110 g m-2). Deagglomerated sepiolite nanofibers in PVB matrix on paper surface were observed by scanning electronic microscopy. The glass transition temperature of schrenz with PVB/sepiolite coatings was not changed with increasing content of sepiolite. Two different methods were used to evaluate the mechanical properties of the paper sample reinforced with PVB/sepiolite nanocomposites: tensile testing and nanoindentation. The values of breaking force and tensile energy absorption of the reinforced paper samples obtained by tensile testing were increased by up 10 %. The values of the reduced elastic modulus and hardness obtained by nanoindentation were increased by up to 78 %. The best improvement of the mechanical properties was shown by the paper sample coated with PVB/3 wt.% sepiolite nanocomposite. [Projekat Ministarstva nauke Republike Srbije, br. III 45019]

sorption of Ni2+ on the sepiolite functionalized by covalent grafting of N-[3-(trimethoxysilyl)propyl]ethylenediamine triacetic acid trisodium salt, MSEAS, was studied in batch experiments as a function of the initial metal concentration, the equilibration time, pH value, and temperature. The modification of sepiolite resulted in an enhanced Ni2+ retention with a capacity of 0.261 mmol/g at 298 K. The retention of Ni2+ ions occurred dominantly by specific sorption and exchange of Mg2+ ions from the sepiolite structure. The sorption process followed pseudo-second-order kinetics. The sorption equilibrium results were best described by the non-linear form of the Langmuir Sorption Equation. The values of the thermodynamic parameters (enthalpy, free energy and entropy) were calculated from temperature dependent sorption isotherms and these values showed that the sorption of Ni2+ onto modified sepiolite was endothermic. [Projekat Ministarstva nauke Republike Srbije, br. III 45019 i FP7 NANOTECH FTM No. 245916]

Primary cardiac tumors are rare, with an incidence of 0,056%. The most of primary cardiac tumors are benign tumors, only 10% are malignant, and 1% from malignant tumors are primary cardiac lymphoma (PCL). From the clinical standpoint, PCL is a non-Hodgkin lymphoma presenting as cardiac disease in rightsided chambers in elderly population. It has been presented young man with Hodgkin PCL, that has been successfully treated with transplantation of the hematopoietic stem cells, leading to stable remission of the disease that has been maintained for 12 years.

Natural sepiolite from Andrici (Serbia) was functionalized by covalent grafting of N-[3-(trimethoxysilyl)propyl]ethylenediamine triacetic acid trisodium salt to the Si-OH sepiolite groups. The functionalized material, MSEAS, was characterized by determination of phase composition by X-ray diffraction (XRD) analysis, analysis of morphological characteristics by scanning electron microscopy (SEM), using Fourier transform infrared (FTIR) spectroscopy, differential thermal analyses (DTA), determination of specific surface areas and pore size distribution using B.E.T. method and point of zero charge (pHpzc) determination. The crystal structure of sepiolite does not change significantly upon surface modification. FT-IR and DTA analysis confirmed that the modified sample maintained the basic structure of sepiolite and also the presence of organic groups in functionalized sepiolite sample. The point of zero charge of MSEAS in KNO3 solutions of different concentrations determination by the batch technique from was at pH 7.0 ± 0.1. [Projekat Ministarstva nauke Republike Srbije, br. III 45019, and FP7 NANOTECH FTM No. 245916]

In this study, the sorption of cadmium ions onto sepiolite modified with hydrated iron(III) oxide, Fe(III)-sepiolite, has been investigated in natural seawater, artificial seawater, aqueous solution of NaCl of the same ionic strength as the seawater and distilled water. The sorption experiments were performed as a function of the initial solution pH value, the initial metal concentration and the equilibration time, using the batch method. The equilibrium sorption data were analyzed by the Langmuir, Freundlich and Sips isotherm models and the kinetics of sorption was analyzed using the pseudo-first-order and the pseudo-second-order kinetic models. The maximum sorption capacity and the strength of the sorbate-sorbent bonds at initial pH = 7 were found to decrease in the following order: distilled water > NaCl solution > artificial seawater > natural seawater. The values of parameter nS in the Sips model, which fitted the equilibrium sorption results best, showed that heterogeneity of the sorbent surface was the highest in distilled water and the lowest in natural seawater. The sorption kinetic data fitted well with the pseudo-second-order kinetic model, which suggests that the rate-limiting step in Cd2+ sorption onto Fe(III)-sepiolite could be chemisorption. The low desorption percentage in both distilled water and 0.001 M HNO3 indicated that sorption occurred mainly by chemisorption mechanisms. [Projekat Ministarstva nauke republike srbije, br. III 45019]

The sorption of Cd2+ from natural seawater, artificial seawater, distilled water and NaCl solution of the same ionic strength as the seawater onto zeolite modified by iron(III) oxide (Fe(III)-zeolite) was investigated. The sorption was found to be time, concentration and pH dependent. The sorption capacity at the initial pH = 7 decreased in the following order: distilled water > NaCl solution > artificial seawater > natural seawater. The isotherm study showed that Langmuir isotherm model could be adequately applied for the sorption in distilled water, indicating the homogeneous monolayer coverage at Fe(III)-zeolite surface, while the Freundlich isotherm model showed a better fit than the Langmuir model of the sorption data in saline waters, indicating multilayer heterogeneous coverage at the sorbent surface. The values of Freundlich parameter n suggested that the sorption was a favorable process and bonds between Cd2+ and Fe(III)-zeolite surface were stronger in NaCl solution than in natural and artificial seawater. Kinetics analyzes showed that the mechanism of Cd2+ sorption from natural seawater differed from the sorption mechanism out of distilled water, NaCl solution and artificial seawater. The intra-particle diffusion kinetic model indicated that both boundary layer diffusion and intra-particle diffusion influenced the rate of sorption. [Projekat Ministarstva nauke Republike Srbije, br. III 45019]

In this work, different metal oxides (MO) supported on two types of zeolites: 1) natural clinoptilolite (NZ) and 2) synthetic zeolite, ZSM-5 were prepared and tested as catalysts in the fast pyrolysis of hardwood lignin. NZ was modified with the CaO and MgO by a simple two steps procedure consisting of an ion exchange reaction and a subsequent calcination at 773 K. The synthetic ZSM-5 was modified with several MO species (Ni, Cu, Ca, Mg) by a wet impregnation and calcination at 873 K. Тhe prepared catalysts were characterized by X-ray diffraction analysis (XRD), scanning electron microscopy and energy dispersive X-ray analysis (SEM/EDS) and measurement of specific surface area (BET method). Acid sites were characterized and quantified by pyridine (py) absorption using Fourier transform infrared spectroscopy (FTIR). The catalysts exhibit catalytic activity depanding on modification, reaction temperature and of the MO contents. The highest yield of useful phenol in bio-oil was obtained with NiO/ZSM-5 (34.8 wt.%) which exhibits the highest specific surface area and the highest concetration of Brönsted and Lewis acid sites. The studied catalysts did not increase significantly the content of polycyclic aromatic hydrocarbons (PAHs) and heavy compounds compared to non-catalytic experiment. [Projekat Ministarstva nauke Republike Srbije, br. 172018]

The main purpose of this research was to explain the differences in the adsorption mechanisms and adsorption capacities of natural and Fe(III)-modified zeolite for Pb2+, Zn2+ and Cd2+ ions. The adsorbents were characterized with respect to their phase composition, morphology, specific surface area, cation exchange capacity and point of zero charge. Batch adsorption experiments were performed as a function of the initial ion concentration and temperature, at constant initial pH value of 5.5 ± 0.1. The adsorption isotherms at 25, 40, 55 and 70°C suggest that the sequence of adsorption efficiency of both zeolites is Pb2+ > Zn2+ > Cd2+. The adsorption capacities of both zeolites increased with increasing temperature. The equilibrium adsorption data were best described by the Langmuir adsorption isotherm. This study revealed that the adsorption capacity of the Fe(III)-modified zeolite is much higher than that of natural zeolite for all investigated ions owing to the higher: specific adsorption caused by the new functional groups formed on the zeolite surface; ion exchange due to the presence of easily exchangeable ions; and hydroxide precipitation caused by higher point of zero charge of the Fe(III)-modified zeolite compared to natural zeolite. [Projekat Ministarstva nauke Republike Srbije, br. III 45019]

The sorption of inorganic arsenic species, As(III) and As(V), from water by sepiolite modified with hydrated iron(III) oxide was investigated at 25 °C through batch studies. The influence of the initial pH value, the initial As concentrations, the contact time and types of water on the sorption capacity was investigated. Two types of water were used, deionized and groundwater. The maximal sorption capacity for As(III) from deionized water was observed at initial and final pH value 7.0, while the bonding of As(V) was observed to be almost pH independent for pH value in the range from 2.0 to 7.0, and the significant decrease in the sorption capacity was observed at pH values above 7.0. The sorption capacity at initial pH 7.0 was about 10 mg gˉ1 for As(III) and 4.2 mg gˉ1 for As(V) in deionized water. The capacity in groundwater was decreased by 40 % for As(III) and by 20 % for As(V). The Langmuir model and pseudo-second order kinetic model revealed good agreement with the experimental results. The results show that Fe(III)-modified sepiolite exhibits significant affinity for arsenic removal and it has a potential for the application in water purification processes. [Projekat Ministarstva nauke Republike Srbije, br. III 45019, III 43009 i TR 37010]

Chromium(VI) adsorption from aqueous solutions onto thermo-acid activated sepiolite functionalized with (3-mercaptopropyl)trimethoxy-silane and [3-(2-aminoethylamino)pro-pyl]trimethoxy-silane, was investigated. Scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric and differential thermal analysis, nitrogen adsorption-desorption, and determination of the point of zero charge were used to characterize the obtained adsorbents. It has been established that the silanes were successfully grafted on the thermo-acid activated sepiolite surfaces and that the structure of parent material was preserved during the functionalization. The adsorption of Cr(VI) onto functionalized thermo-acid activated sepiolite was tested as a function of initial pH values at 298 K. The amine functionalized thermo-acid activated sepiolite showed a higher adsorption capacity than the mercapto functionalized thermo-acid activated sepiolite at all studied initial pH values, especially at the initial pH = 2. [Projekat Ministarstva nauke Republike Srbije, br. III45019]

The present research in the study of the effect of application of natural bio-stimulants and slow-release fertilizers on commercial production of begonia (Begonia semperflorens) saplings. Two types of containers were deployed in the production process, whereas the results of the experimental research showed that the application of both slow-release fertilizers and natural bio-stimulants in further production is only justifiable in cases when largevolume containers are deployed in commercial production of sapling. The application of those significantly influences the increase in stalk weight, number of sprouts and number of blossoms. The application of natural bio-stimulants may be justifiable with the saplings that have previously been produced in smaller containers, since they have auspicious effect upon development of the root, i.e. upon its length.

The results of the characterization and the sorption properties of sepiolite from the locality Slovići are presented in this paper. X-Ray diffraction analysis, infrared spectroscopy and differential thermal analysis revealed sepiolite as the main phase and small amounts of magnesite as an impurity. The specific surface area of sepiolite, determined by nitrogen adsorption and by applying the BET equation was found to be 339 m2/g. The point of zero charge was determined by the batch equilibration method, under different conditions, and the shift in the point of zero charge, in the presence of Pb2+, Cd2+ and Sr2+ ions, was investigated. It was determined that the point of zero charge changed with modification of the solid/liquid ratio and by washing the powder, which indicated that under the investigated conditions some dissolution of the sepiolite and impurities took place also influencing the position of the point of zero charge. In the presence of Pb2+, Cd2+ and Sr2"1" ions, the point of zero charge was shifted toward lower pH values denoting specific ion sorption. The greatest shift and, therefore the largest specific sorption, appeared in the case of Pb2+ ions, somewhat less with Cd2+, and the least with Sr2"1" ions. The adsorption isotherms were determined for the Pb2+, Cd2+ and Sr2+ ions, as well as the amounts of these ions that were removed from aqueous media by the ion exchange of Mg2+ ions from the sepiolite structure, depending on the equilibrium ion concentrations. In the case of ion exchange, as in the case of specific sorption, the affinity of sepiolite for the investigated ions can be presented in the following order Pb2+ > Cd2+ > Sr2"1". For the removal of Sr2"1" ions from aqueous media by sepiolite, a third mechanism is important probably, the ion exchange of exchangeable ions from the sepiolite structure channels. As the result of the action of all the sorption mechanisms sepiolite is removes mostly Pb2+ ions, then Cd2+ and least of all Sr2"1" ions from the aqueous media.