AbstractConsidering that three-phase dispersions are common in chemical engineering and biotechnology, and with increasing airlift reactor applications to chemical and biotechnological processes, a experimental study was undertaken in order to investigate the liquid phase hydrodynamics and dispersion in an external-loop airlift reactor on laboratory scale. Experiments were conducted in order to find a relationship between relevant hydrodynamic and mixing parameters of a solidsuspended exter...
Autori: Florina Ungureanu, Maria Gavrilescu, Radu Z. Tudose
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25268

AbstractDrinking water treatment plays an important role in maintaining public health. Chlorine is the most often disinfectant used for microbiological protection of water. Required residual chlorine concentration must be in treated water when it leaves treatment plant, to comply with the regulations. The chlorine residual must be 0.5 mg/L at the entrance into the distribution system and 0.25 mg/l at consumers, according to the law. Any less and there is no guarantee that the water has adequate ...
Autori: Dan Robescu, Diana Robescu, Nicolae Jivan
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25328

Include urmatoarele articole:� Composite membranes with cross-linked matrimid selective layer for gas separation� Determination of organic compounds from different types of coffee by Hplc and Gc-Ecd analysis� An integrated assessment of the suitability of domestic solar still as a viable safe water technology for India� Investigations on the possibility of natural hemp fibers use for Zn(II) ions removal from wastewaters� Removal of acid red 398 dye from aqueous solutions by coagulation...
Autori:
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25340

Abstract Wood has been used as an engineering material because it is low in cost, renewable and strong and it requires low processing energy. Wood has many excellent properties that result from its exceptional combination of microstructural, ultrastructural and molecular features. The main drawback is its dimensional instability in the presence of moisture, which can affects also the biological stability. Wood is susceptible to degradation in a number of ways, including rot or decay, insect a...
Autori: Lucia Dumitrescu, Ileana Manciulea
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25473

Abstract The paper briefly presents the principle, methodology basics and the research opportunities offered by a modified L-joint test for a complex in-field evaluation of wood behaviour in outdoor above ground exposure, corresponding to the biological use class 3. A comprehensive and detailed examination of the tested samples, looking not only to the biological degradation of wood but also to wood cracking and coating performance (cracking, flaking, exfoliation, adherence), was performed an...
Autori: Maria Cristina Timar, Emanuela Beldean, Mihaela Porojan, Lidia Gurau
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25494

Abstract The Jajrood River watershed is one of the main drinking water resources of Tehran, the capital city of Iran. In addition it provides many recreational usages. However, a variety of microbial pollutions is commonly perceived in the Jajrood River, among them a high concentration of coliform group bacteria that has caused strong concerns. In this article, different aspects of microbial pollution as well as the main microbial pollution sources in the region are discussed. Coliform group ...
Autori: Mahdi Jamshidi, Mahdi Maghrebi, Masoud Tajrishy
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25627

An increasing recognition of tillage erosion processes has shown that soil redistribution by tillage directly contributes to soil loss in mechanically and nonmechanically agricultural areas worldwide. Soil translocation by tillage is normally measured by means of tracers, with which a volume of soil is labeled, and therefore yielding tillage erosion rates in a field. Two tracer methods for estimating tillage erosion rates were appraised to understand the adaptability to local conditions in the h...
Autori: Jianhui Zhang, Fucheng Lihttp://www.ecozone.ro/reviste.php?RID=25687

Calcium zincate as an active material in Zn/Ni secondary battery has been successfully synthesized by microwave method. The sample was characterized by X-ray diffraction (XRD), thermogravimetric analysis, scanning electron microscope (SEM), chargedischarge test (CT) and cyclic voltammetry (CV) analysis. The results show that the chemical composition of sample is Ca(OH)2¡2Zn(OH)2¡2H2O with regular spherical shapes. The results from CV and CT measurement indicate that the battery has very high d...
Autori: Mengliang Tong, Xuanyan Liuhttp://www.ecozone.ro/reviste.php?RID=25700

Abstract:In this paper, the mathematical model is improved by considering the density variations of the liquid from the pollution source vs.pollutant’s concentration of this liquid and by including the sorption-desorption term (SDT), which takes into account thisphysical process, played by a first-order decay model defined by two coefficients and an exponent. In order to practically use thisimproved mathematical model, the authors inferred the calculating relationships from automatic processin...
Autori: Daniel Bucur, Esmeralda Chiorescu, Gheorghe Ţigaret
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25783

AbstractThe hydrodynamics of two equipments from a surface water treatment pilot plant has been investigated through residence timedistribution (RTD) experiments using brine solution as tracer. Computational Fluid Dynamics (CFD) procedure, which isincreasingly utilized to study a wide variety of complex environmental fluid mechanics processes, was used to predict the flowpatterns and other properties of flowing fluids (e.g. velocity, concentration of species etc.). In this work, ANSYS Fluent 14....
Autori: Adina Pacala, Alain Liné, Alexandru-Dan Filep, Cosmina-Mariana Militaru, Teodor Todinca
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26030

AbstractA simplified numerical model of the water distribution network of a medium sized town (with 30,000 inhabitants), of elongatedshape, was implemented in EPANET. The decay of chlorine residual concentration in the above mentioned network was studied,using the extended time analysis capabilities of EPANET, for a 3 days period. The water supply system, composed of one tank, 86pipes and 52 nodes is driven by gravity. The chlorine is injected at the tank with a constant concentration amount. Th...
Autori: Andrei-Mugur Georgescu, Sanda-Carmen Georgescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26054

AbstractExcess biomass produced in the degradation processes of organic pollutants is creating environmental challenges for wastewatertreatment plants. The A+OSA system, a modification of the anoxic / oxic (A/O) process via insertion of a sludge holding tankinto a sludge return line, has been demonstrated to be capable of achieving simultaneous nutrient removal and sludge reduction.Here we report the results of an investigation aimed at evaluating the impact of the sludge holding tank on the bio...
Autori: Li Jia
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26207

AbstractEvaluation of radon concentration is a very difficult task and a very important issue, in relation to the protection of human health.This is especially the case when there is an increase in concentration of radon on a deterministic basis, as is the case of nearbyphosphogypsum residues or geological characteristics. Radon gaseous that can be found in the environment occurs mainly fromnatural radioactive decay chains. The gamma ray spectroscopy is a powerful tool in order to monitor the en...
Autori: Marius Stamate
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26441

AbstractLand decay processes caused by erosion are very serious by their long term impact on the quality of soils, surface waters,environment and living standards. This article presents the results of a spatial erosion modelling. A new methodology is herebyproposed to estimate the soil losses caused by water erosion. The method is based on using GIS techniques, and its noveltyconsists in applying the mathematic calculation model on the pixel/ cell level, by using the “overlay” technique, which g...
Autori: Gabriela Biali
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26559

Abstract 18F-FDG is a glucose analog in which the hydroxyl group on the second carbon is substituted with 18F, being used as an indicator of glucose uptake and cell viability. The aim of this work was to synthesize the 18F-FDG and to validate the methodology for the assessment of its both radiochemical and chemical purities, according to the European Pharmacopoeia. The proposed methodology encompasses three chromatographic methods: radio-HPLC, radio-TLC and HS/GC. Radiochemical impurities ...
Autori: Mirela Mihon
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26640

Abstract The recent awareness about recycling also involves the resources used in civil engineering. The use of Recycled Aggregate Concrete (RAC) has several advantages in terms of conservation of natural resources and of reduction of pollution. Although the interest on the use of structural concrete with recycled aggregates is increasing, extensive studies on the mechanical behaviour of such materials that can allow their use in alternative to standard concrete are still lacking. As a conse...
Autori: Marco Breccolotti
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26776

Air change rates and ventilation of a room was determined by CO Tracer Decay Technique. The tracer was generated by burning bulk amount of mosquito coils, an easy and low cost method of CO generation. The temporal decay in CO concentration in indoor air under closed and open room conditions were determined by collecting indoor air periodically at a few minutes interval in Tedler Bags and analyzing the same for CO. The air changes rate per hour (ACH) was calculated from the temporal decline of...
Autori: Deepanjan Majumdar
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26965

The removal of quinoline from synthetic wastewater by heterogeneous photo-Fenton in a novel internal circulating fluidized-bed reactor was investigated systematically. The flow field in the reactor was simulated by FLUENT software conjoined with tracer particles experiment, and the influence of reaction parameters such as initial quinoline concentration, catalysts dosage and H2O2 dosage were evaluated. Results indicated that the designed reactor was suitable for the heterogeneous photo-Fenton...
Autori: Ran Zhang
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27142

Ground water is an important source of clean water supply throughout the world. A growing literature on the management of groundwater which takes into account the interaction of groundwater with surface water resupply sources (e.g., streams or lakes) is driven by concerns of intensified global fresh-water use coupled with increasing industrial and agricultural pollution levels. Our joint laboratory and numerical experiments simulate water withdrawals via two pumping wells from an unconfined aqui...
Autori: Anca Marina Marinov
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27302

The kinetics of azo dye reduction based on combined effect of biochemical reduction by anaerobic mixed culture and chemical reduction with hydrogen sulfide was investigated. Hydrogen sulfide was produced by sulphate reducing bacteria existing in the anaerobic mixed culture. The effect of initial anaerobic biomass, initial substrate, and initial dye (Reactive Orange 107) concentrations on reduction kinetics were studied with batch assays. The municipal waste sludge was used as electron donating s...
Autori: Umay Gokce Ozkan-Yucel
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27386

Timber harvesting and log extraction with conventional ground-based skidding systems in steep, mountainous terrain often results in severe damage to residual stands and forest sites. In this study, the impact of rubber-tired skidders on standing trees along sides of the trails was investigated 5 to 20 years post-harvest in terms of frequency and development of decay at the points of wounding. The study was located in the Hyrcanian mountainous forests of Iran. All standing beech trees (healthy or...
Autori: Davoud Kartoolinejad
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27457

Degradation of Clindamycin phosphate (CMP) was studied in aqueous solutions by an anodic oxidation process under galvanostatic conditions. The electrolysis cell consisted of a Ti/SnO2-Sb anode, prepared by dip-coating technique, and a 316 stainless steel cathode, both of which had a surface area of 6 cm2. The effects of critical factors, including CMP concentration, current density, initial pH, and the supporting electrolyte were evaluated. The electrochemical oxidation of CMP was controlled by ...
Autori: Mitra Gholami
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27639

The study attempted to identify the best suited models to determine the kinetics of chlorine decay and trihalomethanes (THMs) formation in drinking water supplies. Batch experiments were conducted on synthetic water samples to simulate the characteristics of raw water collected from Maithon water treatment plant (MWTP), Dhanbad, Jharkhand, India. Influence of various parameters like total organic carbon (TOC), reaction time, pH and chlorine dose on the rate of THMs formation were analysed. The s...
Autori: Minashree Kumari
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28171

Torrential watershed management actions should be integrated and their results designed to last for a long time. In Romania and in other countries, these actions cover the entire area of the watershed (slopes, banks, and riverbeds). They consist of complex sets of structural and non-structural measures and works designed to control runoffs and erosion, protect social-economic objectives and improve degraded lands. The most vulnerable structures are the hydrotechnical structures, which are place...
Autori: Alin-Lucian Mihalache
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28211