AbstractThe purpose of this study was to investigate the immobilization of denitrifying bacteria on microbial cellulose (MC) for biological denitrification. A novel denitrifying bacterium, Pseudomonas stutzeri, was immobilized in microbial cellulose and introduced into an up flow packed bed reactor in order to remove nitrate from synthetic influent. The MC presented the high biomass concentration throughout the experiment, achieving 3.4 mg biomass/g support. The efficiency of the system for deni...
Autori: Abbas Rezaee, Hatam Godini, Hossein Bakhtou
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25302

AbstractA present challenge for research is to determine how to use the combination of oil, gas and coal most efficiently with the minimum environmental damage. In this paper the authors have compared technologies to produce the electricity using natural gas and coal. The objective of this paper consists in evaluation of the life cycle assessment of the natural gas and coal in order to compare their greenhouse gases (GHG) emissions. In this way, three systems with and without CCS were examined: ...
Autori: Adrian-Alexandru Badea, Cristian Dincă, Gheorghe Lăzăroiu, Tiberiu Apostol
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25355

Abstract When plants are exposed to heavy metals influence, the processes of growth inhibition, ion leakage of all membrane, distribution of pigment and even more death of plants are produced. The physiological and biochemical changes in germinating seedling and cultivation in plastic pots experiments of different plant species (maize, bean, oat, and spinach) were investigated under the influence of copper ions as stress agent. Differences between tolerances against copper excess in the case ...
Autori: Alina Stingu, Irina Volf, Valentin I. Popa
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25578

This paper presents a study of the numerical simulation applied for unsymmetrical dimethylhrazine (UDMH) gas dispersion. This study considers an assumed UDMH store conditions and provides important data regarding the relation between the concentration distribution of UDMH and dispersion distance from the source based on the computation fluid dynamic (CFD) software FLUENT. The simulation results show that the ventilation vent and distance of dispersion play an important role in the concentration ...
Autori: Zhiyong Huang, Guofeng Jin, Xuanjun Wanghttp://www.ecozone.ro/reviste.php?RID=25712

AbstractWater distribution networks are complex systems that require innovative technological solutions enabling an integrated andrational water resource management. This paper presents the application of data analytics approaches on flow and pressure data,continuously measured at crucial points of the network, for improving efficiency of leak localization. The general goal is toreduce time and costs for physical check and consequent rehabilitation activities.Although the general benefits provid...
Autori: Antonio Candelieri, Enza Messina, Francesco Archetti
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26018

AbstractAny hydraulic engineering construction project is a complex open system with large investment, long construction period,complex internal structure and numerous participants, subject to restrictions of time, resource, environment and other conditions.In this paper, the analytic hierarchy process principle and method were used to establish three-layer structure system ofagricultural hydraulic engineering construction, while risks of some agricultural hydraulic engineering construction were...
Autori: Shi-Bao Lu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26159

AbstractPipeline crack-like defects are detected and localized through the monitoring of the transport parameters of the transmissionnetwork. Under SCADA monitoring, accidental gas loss is reduced and the negative environmental impact of the hydrocarbons isavoided. This paper presents a method for the localization of accidental gas leaks, the pressure gradient method combined with afuzzy analysis method, which operates simultaneously both numerical data and lexical arguments in order to accurate...
Autori: Adrian Bucur
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26418

AbstractIn order to diminish the climat changes due to greenhouse gases, the capture from the source, transport and storage of carbondioxide is one of the environmental priorities of the EU until 2050. Transportation of this gas through pipelines (one of thesolutions with most advantages in transport) can be done at ambient temperature only at high pressures, so the carbon dioxide toremain in the supercritical state. In case of underground pipelines, there is a risk of cracking at the wall of th...
Autori: Valentin Zichil
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26447

Abstract Carbon capture and storage is one of the critical technologies that can enable the reduction of carbon dioxide (CO2) emissions of large industrial sites worldwide. The injection of CO2 into saline water formations is related with many factors and processes that control the safety of its long-term storage. This paper analyzes the leakage risks and the factors that influence the integrity of the cap rock in deep saline aquifer formation. Several pathways have leakage potential risks d...
Autori: Xiaojuan Qiao
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26585

Abstract Resilience is meant in this paper as the capability of a networked infrastructure to provide its service even if some components are failed: it depends both on net-wide measures of connectivity and the role of a single component. This paper has two objectives: first to show how a set of global measures can be obtained using techniques from network theory, in particular how the spectral analysis of the adjacency and Laplacian matrices allows us to obtain a characterization of global ...
Autori: Antonio Candelieri
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26746

Abstract On the basis of a generalized irreversible Carnot heat engine (GICHE) model with the losses of heat resistance, heat leakage and internal irreversibility, the local stability of the heat engine at the maximum ecological function (MEF) is studied with Newton’s heat transfer law between working fluid and heat reservoirs. It is derived that a general expression of relaxation time described as stability of the system refers to heat capacity C, overall heat transfer surface area F,...
Autori: Lingen Chen
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=26859

A quick and efficient response to an emergency incident is critical to avoiding further damage, so its evaluation is important before taking real action. In this study, a framework for response strategy evaluation is proposed based on a whole-process risk analysis of historical accidents, which provides a method to compare the efficiency of different response strategies in a hypothetical scenario. The framework is a multi-step procedure consisting of three major steps: system definition, inde...
Autori: Lei Huang
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27041

In this paper the problem of water leakage is shown widely as well as the impact in Mexico resources, which is reflected in a huge economic and environmental impact. Also several leak detection systems and methodologies are presented in a comparative analysis that was carried out in order to provide the reader a clear idea of how the operation of the systems are affected by means of various factors which in turn leads the reader to know about the requirements of systems and methodologies and ...
Autori: Pedro Rosas Quiterio
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27137

Municipal Solid Waste (MSW) disposal is currently one of the major environmental issues in big cities. Several tools and techniques have been developed for Environmental Impact Assessment (EIA) of MSW disposal options, including scoping, checklists, matrices, qualitative and quantitative models and decision-support systems. Rapid Impact Assessment Matrix (RIAM) is a partially new method which is particularly advantageous over others as it provides a transparent and permanent record of analysi...
Autori: Zohreh Aliakbari-Beidokhti
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27465

In this study, the concentrations of 15 phenol derivatives were analyzed from the phreatic and groundwater wells surrounding a decommissioned chemical factory in a village from the western part of Romania. An UPLC-MS method was used to assess the concentrations of the chemical target compounds in the water samples. The most frequent compounds were 4-chlorophenol, 4-tertoctylphenol and 4-nonylphenol, being detected in 17 of the 19 sampling sites, while the least frequent compound was 2,4,6- t...
Autori: Elena Preda
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27661

Leakage through flaws in geofilm was examined with laboratory tests by flexible wall permeameter. Samples cracks were cut open by the sharp blade, with the results that the widths of the flaws were the same while the lengths were different. During the research, a series of laboratory permeameter tests have been performed to determine the influence of the various factors on the leakage rate of water through the flaw at the center of geofilm. The impact of various parameters examined included t...
Autori: Guangwei Zhang
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27674

The current paper is an overview on previous and ongoing research carried out by the authors concerning the use of Computational Fluid Dynamics for the accurate classification of hazardous Ex areas generated by flammable gases, for the optimization of computational simulation of air-methane mixture explosions by using ANSYS CFX and FLUENT and for calibrating computational simulations of gas explosions using the Schlieren effect. These research works containing analytic studies have led to the...
Autori: Vlad Mihai Păsculescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=27962

For efficient management of the losses of drinking water distribution networks, it is essential to have a precise knowledge of the system and its infrastructures. In this context, our study focused on describing two drinking water distribution networks, from two different countries: Rabat and Sale, Morocco and Timisoara, Romania, for water losses over a period of four and five years, respectively. The work consists of calculating some performance indicators to establish thematic maps using Geogr...
Autori: Ziane Imane
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28113

Interest in water recycling has provided opportunities to evaluate the potential impact of pharmaceuticals and personal care products (PPCPs) on plants where recycled wastewater is used for watering and irrigation. Most researches have focused on the impact of pharmaceuticals on seed germination and plant physiology or the uptake of pharmaceuticals into plants. We sought to find out whether nutrient and metal uptake into wheat plants were affected by the presence of PPCPs (acetaminophen, caffein...
Autori: Etem Osma
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28193

Optimal evacuation routes are crucial to protect workers’ safety when accidental leakage of toxic gas occurs in chemical plants. However, the majority of route optimization focuses on the transport field and few on the evacuation routing optimization in chemical plants. This paper proposes a dynamic evacuation routing optimization method for chemical plants under toxic gas release scenarios. From the complete accident scenario set (CASS) built with wind fields and leakage sources, the leak...
Autori: Ying Liu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=28336