AbstractDuring the transition to a market economy, many countries with a planned economy in Central and Eastern Europe face similar challenges when the established socio-economic systems and infrastructures deemed inefficient in a market economy. Also new issues are being raised by the trends of globalization and the vision of sustainable development. In the energy sector the challenges raised by the Kyoto Protocol and its implementation mechanisms are especially interesting, because they are in...
Autori: Andrius Plepys, Giulia Gervasoni, Jean-Philippe Boutin, Kes McCormick, Kristin Seyboth, Luis Mundaca, Marko Ratton, Patrick Lamers, Robert Hlep
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25104

Abstract Increasing the solar energy conversion into electrical or thermal energy represents an European and national priority, because it offers clean alternatives to the use of fossil fuels, in no pollutant systems, based on photovoltaic modules and solar collectors. The global solar radiation is the most important factor affecting the amount of energy produced by a PV module. In direct connection with the change in the solar energy conversion, the TR - Loss Coefficient (Tr??bungsfaktor) is...
Autori: , Dorin Valentin Diaconescu, Maria Valentina Dinicu (Popa), Bogdan Gabriel Burduhos
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25465

Abstract:Drying wood requires a significant amount of thermal energy, in order to heat-up wood and evaporate the water inside it.Therefore, solutions to minimize this consumption are a topic of maximum interest for wood-processing industries. Employingsolar power for drying wood is not a novelty, considering that this possibility was already acknowledged at the end of the 17thcentury, but since then, kiln design was significantly improved, once with the progress of knowledge regarding the mechan...
Autori: Ion Marinescu, Mihaela Câmpean
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25727

Abstract:In order to comply with the 20-20-20 Directive, by which every EU member state has pledged to produce 20% of the energy byusing renewable sources, solar energy for heating became a much addressed to topic, as a viable and up-scalable option. Researchis devoted to increasing the efficiency while reducing the production costs and the development of novel solar thermal systemswith dish collectors can contribute with innovative solutions. Thus, the first step in the development process, the...
Autori: Daniela Ciobanu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25730

Abstract:The operation of solar air heat collectors consists in a sequence of transient regimes, being conditioned by the availability in timeof the solar resource. This paper presents the results of an experimental research on transient regimes of two types of solar air heatcollectors. The absorbers of the collectors have different configurations and are made of different materials. One collector is acommercial passage air collector with the absorber made of aluminum. The other collector is an ...
Autori: Adrian Ciocănea, Andrei Dragomirescu, Sanda Budea
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25731

Abstract:A comparative analysis is drawn on the energetic responses numerically simulated for Brasov, Romania location, delivered bytwo mono-axial pseudo-equatorial STCs (solar thermal collectors): a flat plate STC and a STC with heat pipes; the two systemsare destined for future implementation on Transilvania University Campus. Accordingly, two tracking programs are consideredfor the diurnal motion: a) of 1h constant duration steps, for school courses interval (September-June) and b) 1-step pro...
Autori: Maria M. Vatasescu, Veronica E. Dombi
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25740

Abstract:The paper presents a computer modelling and experimental validation for the thermodynamic performance of parabolic troughsolar collectors (PTSC) used in a micro-combined cooling,e heating and power (mCCHP) system. The thermal efficiency, fluidoutlet temperature, heat gain and heat and optical losses of the collector are calculated depending on the collector geometry,optical properties, fluid properties, fluid inlet temperature and flow rate, solar insolation, wind speed and ambient temp...
Autori: Ion V. Ion, Lizica Simona Paraschiv, Spiru Paraschiv
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25760

Abstract:A thermodynamic model for accurately predicting the overall efficiency and power output of a solar assembly using a Stirlingengine is presented. It is based on the application of the First Law of Thermodynamics for Processes with Finite Speed and usesthe Direct Method. The proposed model could also be used to better design receivers that concentrate the solar radiation and toproperly size the receiver cavity for a dish solar concentrator. Examples of the optimization of the performance ...
Autori: Alexandru Dobrovicescu, Camelia Stanciu, Dorin Stanciu, Georgiana Tirca-Dragomirescu, Monica Costea, Stoian Petrescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25763

Abstract:A thermodynamic model for studying the overall efficiency and power output of a solar assembly using a Stirling engine ispresented. It is based on the application of the energy and exergy balance equations to the system components. The results of theproposed model are generated as a function of solar incident radiation whose analytical estimation is presented. The numericalapplication is set for a solar assembly operating in Bucharest, composed by a parabolic dish mirror, a plane receiv...
Autori: Adina Gheorghian, Alexandru Dobrovicescu, Camelia Stanciu, Dorin Stanciu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25764

AbstractIn this paper we analyzed some characteristics of vacuum sewer systems from technical, economical, environmental and socialperspectives. The vacuum sewer systems transport wastewater with lower pressure (p<pat), and are compared to conventionalsewer systems with free level (p = bed) - gravity and under pressure systems (p>pat) - gravity or pumping systems. Vacuumsewer systems are recommended for rural communities and residential neighbourhoods surrounding urban areas, developed ons...
Autori: Corina Panfil, Ion Mirel, Izabella Szigyarto, Monica Isacu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26035

AbstractBasic principles for assessing phytotoxicity are the same whether the test compound is a heavy metal, herbicide, fungicide,insecticide or other toxic compounds. The difference lies not in the method of evaluation, but in the experimental program andworking methodology.In this paper the phytotoxic effects of heavy metals, Cr (VI) and Cd (II) on plants germination and growth were studied. Stocksolutions of the two heavy metals were prepared at a concentration of 1000 mg/L, in distilled wat...
Autori: Dana Luminiţa Sobariu, , Maria Gavrilescu, Mariana Diaconu, Vasile Lucian Pavel
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26062

Abstract Using lab experiments, the heavy metal tolerance of young ectomycorrhizal trees was assessed in two axenic systems, co-cultures on germination medium and a sandwich technique system with Modified Melin-Nokrans medium. Sterilized seeds of the tree species Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) were inoculated with the ectomycorrhizal fungi Paxillus involutus and/or Tricholoma vaccinum in media containing either 10 mM CsCl or 0.25 mM CdCl2. The behavio...
Autori: Maria Lucia Bizo
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26119

AbstractSupply of heat energy is of the high importance in the northern countries of the Europe. EU energy policy and high prices of theheat energy resources takes a challenge to find any alternative resources for generation of heat energy. Therefore in this paper the integration of renewable energy source - solar energy into the existent heat energy supply system is analyzed as the alternative or additional source of heat energy. The case study of the Girionys boiler-house (at Kaunas district, ...
Autori: Jolanta Dvarionienė
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26201

AbstractIn this study, the experimental performance of a single slope solar still coupled with an evacuated tube collector was investigated. A single slope passive solar still (PSS) and single slope active solar still (ASS) integrated with an evacuated tube collector were fabricated with an area of 1 m2 and tested in the composite climate of Coimbatore, Tamilnadu, India, (Latitude: 11°N; Longitude: 77°E and an altitude of 409 m above sea level). High water  temperatures in the range of 84.2...
Autori: Karuppusamy Sampathkumar, Palanisamy Senthilkumar
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26286

AbstractThe efficiency of solar disinfection (SODIS) was evaluated and enhanced by concentrating sunlight at low pH values in a solar collector disinfection (SOCODIS) system at different sunlight intensities and is highlighted in the author’s earlier findings. In order for further improving the rainwater disinfection, simple technique like wrapping the PET bottles with heat-resistant plastic bags (Wp) were used for enhancing the thermal/synergistic effects of solar radiations. An analysis of the...
Autori: Abdulrahman Ali Alazba, Mooyoung Han, Muhammad Nasir Amin, Muhammad Tahir Amin
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26298

AbstractThe present contribution describes the investigation of a solar air collector for space heating in order to develop more efficientand cost effective energy process. Various configurations of absorber and different air flows through the collector were tested.The influence of the air mass flow on the air outlet temperature and thermal efficiency has been studied. The thermal efficiency,fluid outlet temperature, heat increase and heat losses of the collector are calculated depending on the ...
Autori: Lizica Simona Paraschiv
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26468

AbstractGreywater (GW) has attracted global attention as an alternative water source over the last few decades. GW treatment andreliable reuse require the overall qualitative characterization of samples from different sources. This paper represents aninvestigation of household-generated GW in the Northern Great Plain Region of Hungary. Modern and reliable analyticaltechniques and instruments (ion chromatography, microwave plasma atomic emission spectrometry, Zetasizer Nano Z analysis,etc.) were ...
Autori: Ildiko Bodnar
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26528

AbstractThis paper presents an optimization procedure to minimize the cost of drying in a solar cabinet dryer based on the results of amathematical model. The model has been developed previously for performance analysis of a solar cabinet dryer. The optimalvalues for geometry of the solar collector, mass flux of air through the collector, and initial moisture content are obtained in away that the drying cost is minimized. The results indicate that to optimize the drying cost, the best values of ...
Autori: Samaneh Sami
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26564

Abstract Vacuum-tube thermal collectors are used to collect heat radiated by the sun. This heat is then used to drive the forced evaporation of concentrated seawater (saltwater) released by reverse osmosis and the extraction of NaCl. This paper reports heat consumption during evaporation. About 78.90% of seawater has to be evaporated in advance through insolation to initiate forced evaporation. This step is conducted to precipitate the NaCl because only CaSO4·2H2O are initially precip...
Autori: Huaigang Cheng
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26813

Abstract A large number of energy inefficient buildings were constructed without taking into account the principles of green building, which requires efficient utilization of local resources. In this work hemp and peat fibres were used in order to produce effective ecological thermal insulating material. Tests were carried out using short dishevelled hemp and chopped peat fibres. Effective composites from local renewable resources were produced. Macro- and microstructures of composites as we...
Autori: Rūta Stapulionienė
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26844

Abstract The atmospheric air is considered a large and renewable source of fresh water. The present work investigates the application of solar energy to heat wick clothes impregnated with calcium chloride to extract water from atmospheric air. A wick desiccant solar collector is erected at Tanta – Egypt for this purpose. The desiccant concentration at the beginning of regeneration is determined according to the climatic conditions. The saturated wick desiccant is exposed to an ambient ...
Autori: Abd elnaby Kabeel
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26861

This paper studies, in lab scale, the possibility of removing a rich-in-pollutant soil fraction using flotation, with the clean fraction been restored to its natural condition. The tests were carried out in a conventional flotation cell with mechanical agitation. Artificially polluted soil was used throughout this study by mixing soil with diesel fuel. The effect of the following flotation factors was studied: pulp pH, collector type and quantity, conditioning and flotation time, initial soil...
Autori: Nickolaos Georgiou
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26960

This study aims to evaluate the effects of Fe2+ present in carbonated natural mineral waters on the decomposition of hydrogen peroxide (H2O2) used as sanitizing agent of the collector water tanks and the oxidation of NH4+ to NO3– and NO2– nitrogen compounds from bottled carbonated natural mineral water by the Fenton process. This evaluation suggests that the distribution of the nitrogen compounds, at certain concentrations of H2O2 is influenced by facilitated Fenton reaction in the p...
Autori: Daniela Bogdan
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27279

This study presents the results obtained in tailoring thin films of alumina, deposited onto aluminium substrates by spray pyrolysis, at 250°C, using AlCl3 solutions (0.15M) in a water:ethanol (1:1) solvent mixture. As morphology controlling agents, acetylacetone and maleic acid based copolymers are added in the precursors’ solutions. The precursors’ systems are analyzed by FTIR spectroscopy and the surface morphology of alumina thin films is investigated by atomic force microscop...
Autori: Luminita Isac
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27291

The monomer with ketimine side group, 2-(1-(benzylimino)ethyl)phenol (2-BEP), was synthesized from the condensation of 2- hydroxyacetophenone and benzyl amine. The enzymatic oxidative polymerization of 2-BEP was performed in the presence of hydrogen peroxide using horseradish peroxidase (HRP) as catalyst. The oxidation reaction was carried out in various solvents and phosphate buffers at room temperature. These studies have shown that a dark brown polymer was successfully synthesized by utilizin...
Autori: Senem Tapan
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27377

This study was aimed at eliciting the perception of practitioners on sustainable supply chain management in small and medium enterprises (SMEs). A total of 15 companies from the SMEs in Malaysia were selected. 5 of these companies serve as suppliers to larger firms within and outside Malaysia, another 5 as manufacturers, and the rest as reverse logistics companies (collectors and recycling plant operating companies). All the companies were selected based on their involvement in sustainable su...
Autori: Ezutah Udoncy Olugu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27440

α-cypermethrin is a pyrethroid and environmental genotoxic pesticide extensively used worldwide for agricultural applications. However, like other pesticides, it affects non-target organisms as well as target organisms and causes various toxic effects. To evaluate α-cypermethrin toxicity in non-target organisms, the effect of α-cypermethrin on the activity of malondialdehyde (MDA, an indicator of lipid peroxidation) content, antioxidant enzymes (superoxide dismutase, SOD; perox...
Autori: Ozkan Aksakal
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27647

The performance of cathode affects the overall performance of a microbial fuel cell (MFC), and cathode configuration affects the fabrication cost of this bioelectrochemical system in a large way. Various modifications in cathode structures have been observed in MFCs. Among them air-cathode MFCs are considered to be the most efficient and sustainable option due to elimination of aeration, as required in aqueous cathodes which consumes energy and increases operating cost of MFCs. An air cathode us...
Autori: Pritha Chatterjee
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27680

The research focuses on the assessment of the main agro-productive properties and the evolution of the mollic reddish (red-brown) preluvisol between the Jiu and Olt rivers, under the new conditions of soil formation and exploitation, created after radical transformations in Romanian agriculture, when most of the lands were passed from state to private ownership. The first comparative analysis of the properties of the soil that evolved on the terrains utilized for crop culture on farms and agrito...
Autori: Jenica Călina
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28128

The study presents the experimental testing of a heat exchanger with uniform thermal flux (HEUTF), used as a cold source in HVAC systems with heat pumps. A water-water heat exchanger is tested, having a special geometry, with uniform thermal flux along the system. The heat exchanger proposed consists of a distributor and a collector, connected to each other by means of 20 staggered copper pipes, being suitable for serving low or medium geothermal sources. The innovation consists in the uniformit...
Autori: Sebastian Valeriu Hudișteanu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28340