Electrochemical Removal of Microorganisms in Drinking Water

It is known that silver, even in small concentrations (hundred parts of milligrams per liter), has the ability to destroy microorganisms, i.e. it has strong bactericidal abilities. Cleansing vast amount of water using bactericidal ability of silver is usually performed in electrochemical way. The advantages of electrochemical disinfection process like: (a) environmental compatibility, (b) versatility to kill a wide variety of microorganisms under mild conditions, (c) no need for adding chemical medicines and (d) the benefits of in-situ generation greatly lower problems and dangers of usage gas chlorine in water disinfection, which is greatest during transport and storing of this disinfectant. Appliances for electrochemical disinfection of drinking water eliminate these faults of conventional disinfection methods. Medical researches show that excess of chlorine in water reacts with organic matter, leading to mutations and cancer formation in digestion organs and bladder. This paper represents research of succesful microbiological disinfection of natural water that contains Acinetobacter, Pseudomonas aeruginisa, Sulfate-reducing clostridium, Streptococcus (F), Aeromonas, Citrobacter (F), Esherichia coli, Enterobacter (F) and Bacillus by water-disinfection appliance. This appliance can be used in water systems like water sorces, traps, reservoires, pools etc. (certificate of Clinical Center of Serbia)

Comparison and assessment of electricity generation capacity for different types of photovoltaic solar plants of 1MW in Sokobanja, Serbia

This paper gives the results of the electricity generated by the fixed, one-axis and dual-axis tracking photovoltaic solar plant of 1 MW with flat panels made of monocrystalline silicon which is to be built in the area of Sokobanja (spa in Serbia). Further on follows a description of the functioning of the fixed and one-axis and dual-axis tracking solar plants. For the calculation of the electricity generated by these plants PVGIS program was used. Calculations have shown that fixed photovoltaic solar plant power of 1 MW, solar modules of mono-crystalline silicon yield 1130000 kWh power output, one-axis tracking solar plant yields 1420000 kWh, and dual-axis tracking solar plant yields 1450000 kWh of electricity. Electricity generated by the fixed photovoltaic solar plant could satisfy 86% of the annual needs for the electricity of the 'Zdravljak' hotel and the special 'Novi stacionar' hospital in Sokobanja

ELECTRODEPOSITION AND MORPHOLOGY OF COPPER POWDER PARTICLES OBTAINED AT DIFFERENT CURRENT REGIMES

The effect different deposition regimes (constant and reversing currents), on the powdered copper electrodeposits morphology were investigated. The morphology of electrodeposited copper powder was investigated using a scanning electron microscope (SEM). The effect of the current amplitude, cathodic to anodic time ratio and period of the current wave are discussed. It is shown that the parameters determining the reversing current wave determine the micro-morphology of the copper powder particles deposited

Electrodeposition of Fe Powder from Citrate Containing Electrolytes

Polarization characteristics of the electrodeposition processes of Fe powders from different citrate electrolytes and the morphology of the obtained powders were investigated. The effect of complexing agents on the cathodic polarization, the current efficiency and morphology of electrodeposited Fe powders were investigated. The morphology of obtained powders depends on the kind of supporting electrolyte, but not on the current density in investigated range. A characteristic feature of powders deposited from citrate-chloride supporting electrolyte is cauliflower-like compressed structure. On the other side, Fe powders electrodeposited from citrate-sulfate supporting electrolyte appeared in the form of spongy-like agglomerates. Possibility of Fe powders protection from corrosion in the process of production and during long-term storing has been shown

Electrical Conductivity of Lignocellulose Composites Loaded with Electrodeposited Copper Powders. Part II. Influence of Particle Size on Percolation Threshold

This article is concerned with synthesis and characterization of electroconductive composite materials prepared by the compression molding of mixtures of lignocellulose and electrochemically deposited copper powder under different pressures, and investigation of the influence of particle size on conductivity and percolation threshold of obtained composites. Electrodeposited copper powder content was varied from 2.0-29.8 vol%. Analysis of the most significant properties of individual components and prepared composites included structural and morphological analysis and measurements of hardness and electrical conductivity. Hardness of the investigated composites, as expected, increased with the increase of the processing pressure, as well as lowering the particle size compared to previous work. The significant increase of the electrical conductivity can be observed as the copper powder content reaches the percolation threshold. The packaging effect and more pronounced interpartical contact with smaller, highly porous, highly dendritic particles with high values of specific area lead to "movement" of percolation threshold towards lower filler content, which for the particles LT 45 mu m and highest processing pressure of 27 MPa was 7.2% (v/v). In the investigated range of electrodeposited copper powder concentrations and applied pressures the increase of the electrical conductivity of composites is as much as fourteen orders of magnitude. It was found that this transition occurs at lower volume fractions than stated in the literature which can be due to the filler with high specific area

Influence of Electrolytic Copper Powder Particle Morphology on Electrical Conductivity of Lignocellulose Composites and Formation of Conductive Pathways

Composites based on polymers with conductive fillers have been gaining more significant roles in a variety of technological domains and they are getting in the research focus of numerous studies as a part of growing research trend. Galvanostatically produced copper powder with high values of specific area was used as filler for synthesis of electroconductive composite materials prepared by the compression molding of mixtures of lignocellulose and electrochemically deposited copper powder. This article is concerned with characterization of these composites. Analysis of the most significant properties of prepared composites and its components included measurements of electrical conductivity, impedance spectroscopy (IS) behavior and structural and morphological analysis. Volume fraction of the copper powder was varied from 2.0-29.8% (v/v). The significant increase of the electrical conductivity can be observed as the copper powder content reaches the percolation threshold (PT). It was shown that PT depends on both particle shape and type of spatial distribution. IS measurements have shown that particle morphology having pronounced grain boundaries has great effect on appearance of electric conductive layers. The packaging effect and more pronounced interpartical contact with copper powder particles lead to "movement" of PT, which for the particles LT 45 mu m and highest processing pressure of 27 MPa was 7.2% (v/v). IS response of the composites showed existence of electrical conductive layers, each having different resistivity which increases towards interior of the composite

The Effect of Periodically Changing Regimes on the Electrodeposition of Silver Powder

The effect of different deposition regimes (constant and reversing currents, constant and pulsating overpotential), on the powdered and dendritic silver electrodeposits morphology were investigated. The morphology of electrodeposited silver powder was studied utilizing a scanning electron microscope. The results obtained in constant regimes were compared with those obtained in pulsating and reversing regimes. The size of dendrites decreased strongly with increased overpotential or current. It was also shown that the agglomeration of silver dendrites in spongy-like agglomerates was strongly decreased by pulsating overpotential electrodeposition or reversing current. The possibility of obtaininig powder particles, with different properties, depending on conditions of electrolysis was demonstrated

Electrochemical Removal of Microorganisms in Drinking Water

It is known that silver, even in small concentrations (hundred parts of milligrams per liter), has the ability to destroy microorganisms, i.e. it has strong bactericidal abilities. Cleansing vast amount of water using bactericidal ability of silver is usually performed in electrochemical way. The advantages of electrochemical disinfection process like: (a) environmental compatibility, (b) versatility to kill a wide variety of microorganisms under mild conditions, (c) no need for adding chemical medicines and (d) the benefits of in-situ generation greatly lower problems and dangers of usage gas chlorine in water disinfection, which is greatest during transport and storing of this disinfectant. Appliances for electrochemical disinfection of drinking water eliminate these faults of conventional disinfection methods. Medical researches show that excess of chlorine in water reacts with organic matter, leading to mutations and cancer formation in digestion organs and bladder. This paper represents research of succesful microbiological disinfection of natural water that contains Acinetobacter, Pseudomonas aeruginisa, Sulfate-reducing clostridium, Streptococcus (F), Aeromonas, Citrobacter (F), Esherichia coli, Enterobacter (F) and Bacillus by water-disinfection appliance. This appliance can be used in water systems like water sorces, traps, reservoires, pools etc. (certificate of Clinical Center of Serbia)

Plućna funkcija u radnika s azbestozom

Pulmonary function testing was done in 19 female and 13 male patients suffering from pulmonary asbestosis. Restrictive disturbance of pulmonary function (VC 80%) nađen je u 38,51 % muškaraca i 52,4 žena. Smanjenje ekspiratornog protoka (FEF50 < 60% i FEF25 < 50 %) bilo je prisutno u 53% muškaraca i 43,8% žena s normalnim vrijednostima VC i FEV1 %