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The removal of methomyl, one of the most frequent pesticides, from aqueous solutions has been studied by adsorption using the reactivated carbon microspheres separated from worn filtering protective suits. This study is significant in two aspects - the first is the in-situ adsorption of pesticides from aqueous solutions, and the second is recycling protective equipment as an effective material for water decontamination. Carbamate pesticide, methomyl is aimed to control foliage and soil-borne insect pests on various agricultural product. Also, due its toxicity, it has a great potential for usage in terroristic acts and tactical purposes during military operations. The reactivated carbon (RAC) microspheres were characterized by Scanning Electron Microscopes (SEM). The changes in relative concentration of methomyl during the adsorption onto the surface of the RAC microspheres was determinated using the UV-Visible spectrophotometer. The adsorption process is described by Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich adsorption isotherm models. The adsorption kinetics follows the second-order kinetics model, and the thermodynamics study confirms that the adsorption is exothermic and spontaneous. At optimal conditions, the adsorption capacity was qe = 8.631 mol g-1 × 10-8 and the adsorption rate was k = 0.749 g mmol-1 min-1. The Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich adsorption isotherm models were used to describe the adsorption process. The thermodynamic study of adsorption proves the process is spontaneous with exothermic nature.

Adsorption of carbamate pesticide Methomyl by Co-Beta Zeolite particles prepared by wet ion-exchange method from aqueous solutions was studied. The effect of zeolite and pesticide concentrations, pH value, and sintering temperature on pesticide removal from an aqueous solution was studied. The change of methomyl concentration during the adsorption was followed using the UV-Visible spectrophotometer. Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDS) revealed the modified zeolite morphology and elemental structure. The change of the adsorbent surface before and after dye removal was observed using the Fourier Transformation-infrared spectroscopy (FT-IR). The adsorption kinetics follows the pseudo-second-order kinetics model, and at optimal condition adsorption rate is k1 = 0.0166 g mg-1 min-1. The Langmuir, Freundlich, Temkin and Dubinin-Radushkovich adsorption isotherm models were used to describe the adsorption process. Thermodynamic parameters were also determined using experimental data. The thermodynamic study indicates that during pesticide adsorption is, chemisorption and physisorption are present at the same.

Introduction/Objective. COVID-19 pandemic caused many disruptions in the daily routines of children and adolescents, which may have influenced their mental health. This study aimed to examine the impact of the COVID-19 pandemic on self-harming behaviors, including non-suicidal self-injury (NSSI) and suicide attempts in children and youth seeking psychiatric help. Methods. Retrospective, cross-sectional study was conducted, analyzing data from medical documentation of 1129 outpatients, aged between 10 and 18, who had their first psychiatric examination at the Institute of Mental Health in Belgrade, Serbia between March 1, 2019 and August 31, 2021. The frequency of NSSI and suicide attempt during the pandemic was compared to a one-year period before the pandemic. Results. Proportions of patients with NSSI were higher in both years during the pandemic (18.1%; 27.7%) compared to the year before (12.6%), especially in the second year of the pandemic, with a marked increase in March 2021. NSSI was more frequent in girls, older adolescents, those living in incomplete families and those with a history of abuse. No significant change in the frequency of suicide attempts related to the COVID-19 pandemic was found. Conclusion. Significant increase in the frequency of NSSI, markedly during the second year of the pandemic, especially in children and youth with additional factors of vulnerability, calls for further attention from both professionals and policymakers, as well as preventive measures for this vulnerable group during stressful times.

Adsorption of anthraquinone dye Acid Blue 111 by alumina-iron oxide doped particles prepared by sol-gel method from aqueous solutions was studied. The adsorbent morphology was revealed by FESEM and the crystallographic phase is analyzed by the XRD technique. The effect of adsorbate and adsorbent concentrations, pH value, type of adsorbent and thermodynamic parameters on dye removal by adsorption was studied. The change of dye concentration during the adsorbtion was followed using the UV-Visible spectrophotometer. The change of the adsorbent surface before and after dye removal was observed using the Fourier Transformation-infrared spectroscopy (FT-IR). The adsorption kinetics is in accordance with the pseudo-second-order kinetics model. The Langmuir and Freundlich adsorption isotherm models were used to describe the adsorption process. The thermodynamic study of dye adsorption proves the process is spontaneous with exothermic nature.

Appropriate healthcare and psychological support for children and adolescents is essential for the successful development and good mental health. Unfortunately, this is often a neglected element in the healthcare systems around the world. It is known that approximately half of all adult psychiatric disorders start under the age of 14 and that the prevalence of child and adolescent-onset psychiatric conditions is increasing. The real reason for this increase remains unclear, but it demands our attention as does the care of affected children, adolescents, and their families. Transitions between different age groups need to be made easily navigable for the patients and their families. Many challenges in child and adolescent psychiatry are present, especially in developing countries such as Serbia. A possible solution for overcoming these challenges is uniting the child and adolescent professional societies from all over the world. These societies should work together to develop unified strategies for diagnosis, treatment and support of children affected by psychiatric conditions. By working closely with pediatricians, family physicians, psychologists, nurses, and other professionals, child and adolescent psychiatry can use knowledge and skills to support practice while teaching other professionals how to optimize the utilization of child and adolescent psychiatry services.

In recent decades an increase usage of chemicals in many ways of modern life is evident. So, the possibility of its intake into organisms, human and animals poisoning and health damage, is nowadays on a high level, especially when it comes to disaster situations caused by using toxic chemicals in terrorist attacks or for military purposes. If we look ahead, the risk of pesticide contamination of the water and soil, as one of the most important resources for surviving, is always present. The wide spectra of pesticide negative effects on the environment initiate the increasing number of investigations of efficient pesticide removal methods, especially from water. The aim of this study was to investigate the efficiency of direct electrochemical oxidation as a method for in-situ degradation of pesticides in the aquatic environment, depending on the concentration of pesticides, present electrolytes, applied current and the pH value of the medium. As a model molecule, the neonicotinoid pesticide thiamethoxam was used. Kinetics of thiamethoxam degradation in aqueous solution was followed by UV/Vis spectrometry.

The flow of air and aerosol particles through the filtering half masks material depends on the structure porosity. It is very difficult to determine the behaviour of the filtering material during the process of extraction and retention of aerosols. The samples of five filtering half mask models were used in this investigation. Dynamics of the aerosol filtration through the filtering materials was tested using a method for testing the leakage of aerosol particles through the filtering material and a method for testing the inhalation resistance of filtering material, both specified in the SRPS EN 149:2013. Recording of the structural changes in the samples of the tested materials was carried out by the technique of scanning electron microscopy. The experiments showed a deviation of the results in relation to the theory of filtration the finely dispersed submicron sized particles. It was concluded that the aerosol leakage through the filtering half masks and their resistance to aerosol flow change depend on the aerosol flow rates and the on filtration process duration, as a direct consequence of the newly-made changes in the structure of the filtering material and due to reversibility effect between the filtration process and the changes in the filtering material. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR34034 and Grant no. III45019]

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Experimental acquisition and verification of structural properties of an actual helicopter main rotor blade segment have been done with an aim to validate the capability of bonded joints of these structural elements to sustain the most dominant dynamic loads in forward flight, for the assigned blade's life time. It was also one of the qualitative tests of the newly applied rotor blade hybrid structure production technology, consisting of a metal spar and 21 plastic composite segments, bonded to it after the polymerization process. Because of the structural similarity of the segments, only the most highly loaded 21st segment and adjacent spar section were investigated, as representative in this particular sense. This has enabled remarkable reduction both in time and funds required for the design and construction of the test facility. This paper is focused on the demonstration of usage of fairly low-cost experimental infrastructure for that purpose, and also provides the designers and engineers with some examples and guidelines of how it is possible to conduct experimental verifications of the properties of similar, both aeronautical and non-aeronautical hybrid structures and joints, exposed to the long-lasting dynamic loads. Tests presented in this paper were only a part of a very wide test campaign, mostly undertaken on the entire new hybrid blade structures, both on the ground and in flight, before they have been put to operational service. [ABSTRACT FROM AUTHOR]

This paper presents a practical example of the measurement and analysis of vibrations in the first two stages of the axial-flow compressor with intention to estimate a connection between inlet air flow distortions and appearance of stalling of the compressor blades. The inlet air flow distortions were tested during different regimes of the aircraft flight with a maximum thrust, with an assumption that the asymmetry of air flow through the twin-inlets existed and had effect on vibrations of the compressor. The paper shows the measurement of vibrations on the Galeb G-2 aircraft powered by the Rolls Royce Viper Mk22-6 engine with the aim to recognize and define the minimum necessary data for detection of the potential distorted air flow through the compressor, as consequences of an unequal air flow distribution in the inlets. The detection capability of this methodology of measurement is presented using the fast Fourier transform (FFT). The proposed methodology of measurement and analysis can be implemented in different types of aircraft in order to research the occurrence of stall and surge.

Sizing and location of the piezoelectric actuators and sensors for vibration control of flexible structures is usually based on maximum control effectiveness and achieving the maximum output for the vibration in the modes of interests. Integration of piezoelectric patches affects the mass and the original dynamic properties of the parent structure. This is the first part of the two-paper research which presents the theoretical development of the multi-objective fuzzy optimization technique of sizing and location of the collocated piezoelectric actuators and sensors on the thin-walled composite beam. The optimization criteria for the optimal size and location of piezoelectric A/Ss are based on the degree of controllability (DC) for controlled modes. The optimization procedure implies the constraining of the original dynamic properties change and the limitation of the mass increase. A pseudogoal function, derived based on the fuzzy set theory, gives an expression for global objective functions eliminating the use of weighting coefficients and penalty functions. the particle swarm optimization technique is used to find the optimal configuration..

This is the second part of a two-paper research of the multi-objective fuzzy optimization of sizing and location of the collocated piezoelectric actuators and sensors on the thin-walled composite beam. The first paper is focussed on the theoretical model of a optimization techique for optimal sizing and location of piezoelectric actuators and sensors on a smart structure for active vibration control. In this part, the numerical analysis of the presented optimization technique will be presented for the cantilever composite beam with and without limitations in degrees of controllability (DCs) for residual modes.

Piezoelectric actuators are widely used in structural systems for active vibration control with the aim to enhance the performance of systems. The developed system of active vibration control consists of active structure, controller and high voltage amplifier. In this paper, the composite beam is host structure for sensor platform (strain gages) and actuator platform (dual layer PZT piezoelectric actuator). In order to improve the dynamic characteristics of active system, the coefficients of PID controller are changed. The effectiveness of active vibration control system at mode of interest can be improved with change of PID coefficients, but the stability of system can be reduced. The instability of the active structure is often perturbed by spillover effect. In this paper the importance of considering spillover effects in closed loop of piezoelectric active structures is demonstrated and shown the importance of change the PID coefficients in stability of active vibration control system. Experimental results which correspond to the developed active vibration control system are presented and affirmed stability on proposed active structure.

Increasing velocity combined with reduced mass of modern high speed trains poses the question of influence of strong cross winds on its aerodynamics. Strong cross winds may affect the running stability of high speed trains via the amplified aerodynamic forces and moments. In this study, simulations of turbulent cross wind flows over the leading and end car of ICE-2 high speed train have been performed at different yaw angles The train aerodynamic problems are closely associated with the flows occurring around train. The flow around the train has been considered as incompressible and was obtained by solving the incompressible form of the unsteady Reynolds-Averaged Navier-Stokes (RANS) equations combined with the realizable k-epsilon turbulence model. Important aerodynamic coefficients such as the side force and rolling moment coefficients have been calculated for yaw angles ranging from -30° to 60° and compared to results obtained from wind tunnel tests. The dependence of the flow structure on yaw angle has also been presented.

Background: In contrast to the rational (IQ) and emotional intelligence (EQ), spiritual intelligence (SQ) is often underestimated and insufficiently investigated. This type of intelligence refers to our approach to the issue of the meaning and value of life, in terms that our actions are placed in a wider context. Objectives: The aim of this paper is to investigate in which extent spiritual intelligence determines the decision making process. In this context, the success of business decision is assigned as its functionality as one of the most prominent feature of successful decision. Methods: The inductive method of building an expert system, i.e. a knowledge based system (Doctus Knowledge-Based Expert System Shell) and casebased concluding on the degree of informativeness (with a key impact on functionality of decision) of individual components (Case Based Reasoning) are used in testing this relationship. Results: The study demonstrates the fact that most of respondents (managers) have not been even familiar with attributes of SI as well as their relationship with decision making process. Conclusions: Identification of the most significant components of SI that affect effectiveness of decisions would allow managers to focus on those which mostly contribute to the functionality of their decisions.

The majority of wind turbine research is focused on accurately efficiency prediction. This work highlights the progress made in the development of aerodynamic models for studying Vertical-Axis Wind Turbines (VAWTs) with particular emphasis on stream tube approach. Numerical and analytical investigation is conducted on straight blade fixed pitch VAWT using NACA0012 airfoil as a blade profile to assess its performance. Numerical simulation is done for two-dimensional unsteady flow around the same VAWT model using ANSYS FLUENT by solving Reynolds- averaged Navier-Stokes equations. Finally, comparison of the analytical results using double multiple stream tube (DMST) model with computational fluid dynamics (CFD) simulation has been done. Both the CFD and DMST results have shown minimum and/or negative torque and performance at lower tip speed ratios for the modeled turbine, which implies the inability of NACA0012 to self start.

This paper presents the multi-objective fuzzy optimization of sizing and location of piezoelectric actuators and sensors on the thin-walled composite beam for active vibration control, using the degree of controllability (DC) for controlled modes as optimization criteria. The optimization process is performed constraining the original dynamics properties change including the limitation of increase of the mass, using or neglecting the limitation in degrees of controllability for residual modes for reduction spillover effect. Pseudogoal functions derived on the fuzzy set theory gives a unique expression for global objective functions eliminating the use of penalty functions. The problem is formulated using the finite element method based on the third-order shear deformation theory. The particle swarm optimization technique is used to find optimal configuration. Several numerical examples are presented for the cantilever beam.