Influence of magnetic field on the aragonite precipitationLucija Črepinšek-Lipuš
, Danijela Urbancl
, 2007, izvirni znanstveni članek
Opis: Many laboratory investigations of magnetic water treatment (MWT) for scale control explained the formation of less compact scales by raised portion of aragonite, which is needle-like and less adhesive than rhombohedral calcite crystals, while our experiment was conducted with tap water, which contains Mg+2 and Fe+2 ions in concentrations exceeding thresholds for calcite inhibition, common for major tap waters. MWT efficiency was evaluated by amounts of scale precipitated in boilers and pipes during three-weeks run of two parallel experimental lines-one with and another without magnetic treatment. All scales were identified by X-ray diffractometer to be aragonite,but in the case of magnetic treatment, scales occurred in much smaller amounts: the scale on heating copper-pipe spiral was 2.5-times thinnerdue to MWT and in zinc-coated steel pipe occurred as very thin powder-like coating, while in the line without the treatment abundant hard lining was formed. The scalesć morphology was observed by scanning electron microscope: the husks from both lines consisted of parallel distributed needles, but these crystals were about four times thinner in the case of MWT. The present work demonstrates that hard scale deposits can form even under conditions where aragonite precipitates predominantly, and that MWT can also affect the crystallization of this polymorph in a manner conducive to scaling control.
Ključne besede: water, magnetic water treatment, scale, aragonite, cristallization, water supply pipes
Objavljeno: 01.06.2012; Ogledov: 1297; Prenosov: 68
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The influence of physico-chemical parameters on water scale precipitation on washing machines' heatersDanijela Urbancl
, Darko Goričanec
, Jurij Krope
, 2007, strokovni članek
Opis: The paper presents the results of analysis of physico - chemical parameters influence on the intensity of water scale precipitation on washing machines heaters. Washing machines of the same producer were, to this end, modified to an endless cycle of washing with the same amount of cotton fabric at the same conditions. On the basis of various experiments it was determined that water hardness, the amount of exceeded carbon dioxide, water turbulence around the heater, the amount of cotton fibres in water exceeded from fabrics, and heater specific heat strength have the key role in water scale building up in washing machines heaters.
Ključne besede: magnetic water treatment, magnetic hydrodynamics, water scale, calcium carbonate, scale prevention, washing machine, electrical heater
Objavljeno: 21.12.2015; Ogledov: 737; Prenosov: 48
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Magnetic field effects on redox potential of reduction and oxidation agentsMojca Božič
, Lucija Črepinšek-Lipuš
, Vanja Kokol
, 2008, izvirni znanstveni članek
Opis: Redox potentials of two reducing (sodium dithionite and glucose) and two oxidizing (hydrogen peroxide and sodium hypochlorite) agents were monitored at various concentrations and at different temperatures for 30-75 minutes after the exposure of their water solutions (glucose and hypochlorite solutions once; sodium dithionite and hydrogen peroxide solutions one, two and/or three-times) to the static magnetic field of flux density of 0.9 V s M-2 . The aim of the investigation was to suggest improvements, i.e., intensification and stability, of the reduction-oxidation ability of selected agents applicable in textile fibre processing, primarily bleaching and vat dyeing. Results of the experiments show that magnetic treatment (of solutions) raises both the reducing ability of glucose and the oxidation ability of hydrogen peroxide and sodium hypochlorite, promising some technological and economical benefits for the textile industry as well as forother fields of chemistry.
Ključne besede: magnetic water treatment, sodium dithionite, glucose, hydrogen peroxide, sodium hypochlorite, redox potential, textile vat processing
Objavljeno: 05.07.2017; Ogledov: 351; Prenosov: 54
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