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U XXI veku uobičajeni obrazac ponašanja ljudi uključuje provođenje u proseku 20h dnevno u zatvorenom prostoru i shodno tome malo vremena na otvorenom. Ovaj obrazac ima za posledicu mnoge hroniče bolesti ali i poseban značaj za alergijske bolesti. Povećane temperature mogu povećati populaciju grinja ili bubašvaba, i nameštaj će postati rezervoar akumuliranih alergena unutar kuće. Dok su alergije ranije bile redak zdravstveni poremećaj, danas epidemiološka istraživanja pokazuju da oko 25% ukupne svetske populacije boluje od neke alergijske bolesti. Uprkos razvoju farmakoterapije broj obolelih se svake godine povećava, i ima tendenciju daljeg rasta u svim starosnim kategorijama. U Evropi, prema podacima EAACI (The European Academy of Allergy and Clinical Immunology), više od 150 miliona građana pati od hroničnih alergijskih bolesti.. Procenjuje se da će do 2025. godine više od 50% stanovnika Evrope patiti od alergijskih bolesti. U Institutu za virusologiju, vakcine i serume “Torlak” u Beogradu se proizvode alergenski ekstrakti koji se koriste za in vivo dijagnostiku i alergensku imunoterapiju (AIT). Prema dostupnim podacima grinje su jedan od najučestalijih inhalatornih alergena u Srbiji. Cilj ovog master rada je bio da se ispita uticaj različitih ekstrakcionih procedura na kvalitet ekstrakta kao i da se odredi sadržaj ključnih – major alergena. Korišćena su 3 različita puferska rastvora određenih koncentracija za ekstrakciju glavnih (major) alergena Dermatophagoides pt. na različitim temperaturama, a zatim je imunohemijskim metodama poređena njihova efikasnost. Dobijeni rezultati pokazuju da je ekstrakcija 0,15 M fosfatnim puferom na temperaturi 2-8°C najefikasnija za dobijanje većih količina Der p1 i Der p2 alergena.

Here, we report the design of a disposable single-drop voltammetric sensor for the quantitative determination of antipsychotic drug trifluoperazine (TFP). The sensor was built using inkjet-printed carbon nanotube (CNT) electrodes, which were modified with dimercaptosuccinic acid (DMSA)-coated magnetite nanoparticles uniformly dispersed over reduced graphene oxide nanosheets (DMSA/Fe3O4/RGO). The used modifying materials were characterized by electron microscopy techniques (transmission electron microscopy (TEM) and field emission-scanning electron microscopy (FE-SEM)), X-ray powder diffraction, ζ-potential measurements, dynamic light scattering (DLS), and electrochemical methods (cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)). The developed sensor, best operated at pH 7 in the Britton-Robinson buffer solution (BRBS), shows linear electrocatalytic activity with TFP in the concentration range of 1-50 μM, a low detection limit of 0.54 μM, and excellent selectivity, repeatability, and reproducibility with an relative standard deviation (RSD) of 2.4%. A voltammetric approach using square wave voltammetry (SWV) is a sensitive technique under optimized conditions for the analytical determination of submicromolar amounts of TFP. Bare CNT and RGO- and DMSA/Fe3O4-modified CNT electrodes showed lower electrocatalytic activity than the DMSA/Fe3O4/RGO/CNT electrode. The development of this kind of TFP sensor based on nanoparticle-decorated graphene nanosheets can offer a tool for point-of-care applications as sensors in biomedicine.

A disposable acetaminophen biosensor based on inkjet-printed CNT electrodes (IJPCNT) modified with amidase/cerium dioxide@graphene nanoribbons composite was developed (ACeO2@GNR/IJPCNT). The enzyme amidase A was used for the first time as a recognition element. Inkjet-printed CNT electrodes served as a basis for the construction of a biosensor that enables droplet detection using 5 μL sample volume. The biosensor showed high selectivity, sensitivity, a low detection limit of 0.18 μM and a wide working linear range from 1 to 100 μM. The proposed approach allows fast and reliable detection of acetaminophen in biological fluids with negligible matrix effect and remarkable reproducibility. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

A disposable acetaminophen biosensor based on inkjet-printed CNT electrodes (IJPCNT) modified with amidase/cerium dioxide@graphene nanoribbons composite was developed (ACeO2@GNR/IJPCNT). The enzyme amidase A was used for the first time as a recognition element. Inkjet-printed CNT electrodes served as a basis for the construction of a biosensor that enables droplet detection using 5 μL sample volume. The biosensor showed high selectivity, sensitivity, a low detection limit of 0.18 μM and a wide working linear range from 1 to 100 μM. The proposed approach allows fast and reliable detection of acetaminophen in biological fluids with negligible matrix effect and remarkable reproducibility.

Nicotine degradation efficiency in water solutions was studied using a water falling film dielectric barrier discharge (DBD) reactor. Two different treatments were applied: direct treatment, the recirculation of the solution through a DBD reactor, and indirect treatment, the bubbling of the gas from the DBD through the porous filter into the solution. In a separate experiment, samples spiked with nicotine in double distilled water (ddH(2)O) and tap water were studied and compared after both treatments. Furthermore, the effects of the homogeneous catalysts, namely, Fe2+ and H2O2, were tested in the direct treatment. Nicotine degradation efficiency was determined using high-performance liquid chromatography. A degradation efficiency of 90% was achieved after the direct treatment catalyzed with Fe2+. In order to analyze the biodegradability, mineralization level, and toxicity of the obtained solutions, after all degradation procedures the values of the following parameters were determined: total organic carbon, chemical oxygen demand, biochemical oxygen demand, and the Artemia salina toxicity test. The results showed that an increase in biodegradability was obtained, after all treatments. A partial nicotine mineralization was achieved and the mortality of the A. salina organism decreased in the treated samples, all of which indicating the effective removal of nicotine and the creation of less toxic solutions. Nicotine degradation products were identified using ultrahigh-performance liquid chromatography coupled with a linear ion trap Orbitrap hybrid mass spectrometer and a simple mechanism for oxidative degradation of nicotine in non-thermal plasma systems is proposed.

The electric power system of the Republic of Serbia relies mostly on lignite-fired thermal power plants, with 70% of the total electricity generation. Most of these plants are over 30 years old, and investment in their modernization is necessary. The energy efficiency of the 110 MW coal-fired power plant in which the condenser is cooled by the mechanical draught wet cooling towers system is analyzed in this paper. Attention is primarily devoted to operating conditions of the cold end of the plant, i.e. to the interrelationship of the condenser and cooling towers. Most important parameters that affect the operation of the cooling towers system are ambient air temperature and relative humidity, specific mass flow rate, and temperature of cooled water. With the existing cooling system, the overall energy efficiency of the plant is low, especially in the summer months, even less than 30%, due to adverse weather conditions. By upgrading existing cooling tower system by adaptation of two additional cooling tower cells, overall energy efficiency can be increased by 1.5%. The cooling tower system rehabilitation investments payback period is estimated to be less than one year. Static method for economic and financial assessment is used.

A thermal power plant (TPP) uses large amounts of fresh water, mostly for cooling purposes. Among different types of cooling systems, once-through cooling is the most water-intensive and has the greatest environmental impacts. From the view-point of the steam cycle efficiency, this type of cooling still provides the most efficient electricity production, and therefore is widely used. Water is withdrawn from nearby water bodies, absorbs heat from the steam in a condenser, and then discharged back to its original source at higher temperatures causing severe environmental impacts, including fish killing, disturbing ecosystems, and heating-up natural water bodies. The total installed capacity of almost 1100 MW on the right bank of the Danube in Serbia threatens the ecosystem of this large international river due to thermal pollution. This problem will be even more pronounced in the near future, due to an inevitable increase in production capacity for new 350 MW, currently under construction. Herein, analysis of the legal framework for the protection of water from thermal pollution as well as analysis of the actual situation on the site of the TPP "Kostolac" in Serbia are presented. Based on meteorological and hydrological parameters, configuration and operation parameters of the plant, the numerical simulation of the condenser was carried on. The temperature of the water leaving condenser and amount of heat discharged back to the river are obtained. According to those results, the analysis of the existing thermal pollution of the Danube River in the flow through Serbia is given by numerical simulation using software ANSYS CFX. Analysis of thermal discharge into the Danube for the five-year period has been carried out. The cooling water effluent causes a temperature increase in the area of the right bank of the Danube, and this thermal disturbance extends along the right river bank for kilometers. Note that the flow rate of the Danube is currently large enough to compens

The formation of hydroxyl radical and long-living chemical species (H2O2, O-3, NO3- and NO2-) generated in the liquid phase of a water falling film dielectric barrier discharge in dependence on the gas atmosphere (air, nitrogen, oxygen, argon and helium) was studied. The chemical molecular probe dimethyl sulfoxide was employed for quantification of. OH, and the influence of hydroxyl radical scavenging on formation of reactive oxygen and nitrogen species was investigated. In addition to liquid analysis, plasma diagnostics was applied to indicate possible reaction pathways of plasma-liquid interaction. The highest. OH production rate of 1.19 x 10 (5) mol l (1) s (1) was found when water was treated in oxygen, with a yield of 2.75 x 10(-2) molecules of. OH per 100 eV. Formation of hydrogen peroxide in air, nitrogen and argon discharges is determined by recombination reaction of hydroxyl radicals, reaching the highest yield of about 0.7 g kWh(-1) when distilled water was treated in argon discharge. Ozone formation was dominant in oxygen and air discharges. Strong acidification along with formation of reactive nitrogen species was detected in water treated in air and nitrogen discharges.

Electricity is a key energy source in each country and an important condition for economic development. It is necessary to use modern methods and tools to predict energy consumption for different types of systems and weather conditions. In every industrial plant, electricity consumption presents one of the greatest operating costs. Monitoring and forecasting of this parameter provide the opportunity to rationalize the use of electricity and thus significantly reduce the costs. The paper proposes the prediction of energy consumption by a new time-series model. This involves time series models using a set of previously collected data to predict the future load. The most commonly used linear time series models are the AR (Autoregressive Model), MA (Moving Average) and ARMA (Autoregressive Moving Average Model). The AR model is used in this paper. Using the AR (Autoregressive Model) model, the Monte Carlo simulation method is utilized for predicting and analyzing the energy consumption change in the considered tobacco industrial plant. One of the main parts of the AR model is a seasonal pattern that takes into account the climatic conditions for a given geographical area. This part of the model was delineated by the Fourier transform and was used with the aim of avoiding the model complexity. As an example, the numerical results were performed for tobacco production in one industrial plant. A probabilistic range of input values is used to determine the future probabilistic level of energy consumption.