Search results for: Leila Ghorbanian
128 Preparation and Characterization of Silk/Diopside Composite Nanofibers via Electrospinning for Tissue Engineering Application
Authors: Abbas Teimouri, Leila Ghorbanian, Iren Dabirian
Abstract:This work focused on preparation and characterizations of silk fibroin (SF)/nanodiopside nanoceramic via electrospinning process. Nanofibrous scaffolds were characterized by combined techniques of scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD). The results confirmed that fabricated SF/diopside scaffolds improved cell attachment and proliferation. The results indicated that the electrospun of SF/nanodiopside nanofibrous scaffolds could be considered as ideal candidates for tissue engineering.
Keywords: electrospinning, nanofibers, silk fibroin, diopside, composite scaffoldProcedia PDF Downloads 194
127 Numerical Simulation of Plasma Actuator Using OpenFOAM
Authors: H. Yazdani, K. Ghorbanian
Abstract:This paper deals with modeling and simulation of the plasma actuator with OpenFOAM. Plasma actuator is one of the newest devices in flow control techniques which can delay separation by inducing external momentum to the boundary layer of the flow. The effects of the plasma actuators on the external flow are incorporated into Navier-Stokes computations as a body force vector which is obtained as a product of the net charge density and the electric field. In order to compute this body force vector, the model solves two equations: One for the electric field due to the applied AC voltage at the electrodes and the other for the charge density representing the ionized air. The simulation result is compared to the experimental and typical values which confirms the validity of the modeling.
Keywords: active flow control, flow-field, OpenFOAM, plasma actuatorProcedia PDF Downloads 224
126 Catalytic Performance of Fe3O4 Nanoparticles (Fe3O4 NPs) in the Synthesis of Pyrazolines
Authors: Ali Gharib, Leila Vojdanifard, Nader Noroozi Pesyan
Abstract:Different Pyrazoline derivatives were synthesized by cyclization of substituted chalcone derivatives in presence of hydrazine hydrate. A series of novel 1,3,5-triaryl pyrazoline derivatives has been synthesized by the reaction of chalcone and phenylhydrazine in the presence of the Fe3O4 NPs, in high yields. The structures of compounds obtained were determined by IR and 1H NMR spectra. Fe3O4 NPs was recycled and no appreciable change in activity was noticed after three cycles.
Keywords: pyrazoline, chalcone, nanoparticles, Fe3O4, catalyst, synthesisProcedia PDF Downloads 338
125 Equations of Pulse Propagation in Three-Layer Structure of As2S3 Chalcogenide Plasmonic Nano-Waveguides
Authors: Leila Motamed-Jahromi, Mohsen Hatami, Alireza Keshavarz
Abstract:This research aims at obtaining the equations of pulse propagation in nonlinear plasmonic waveguides created with As2S3 chalcogenide materials. Via utilizing Helmholtz equation and first-order perturbation theory, two components of electric field are determined within frequency domain. Afterwards, the equations are formulated in time domain. The obtained equations include two coupled differential equations that considers nonlinear dispersion.
Keywords: nonlinear optics, plasmonic waveguide, chalcogenide, propagation equationProcedia PDF Downloads 254
124 Fault Diagnosis of Manufacturing Systems Using AntTreeStoch with Parameter Optimization by ACO
Authors: Ouahab Kadri, Leila Hayet Mouss
Abstract:In this paper, we present three diagnostic modules for complex and dynamic systems. These modules are based on three ant colony algorithms, which are AntTreeStoch, Lumer & Faieta and Binary ant colony. We chose these algorithms for their simplicity and their wide application range. However, we cannot use these algorithms in their basement forms as they have several limitations. To use these algorithms in a diagnostic system, we have proposed three variants. We have tested these algorithms on datasets issued from two industrial systems, which are clinkering system and pasteurization system.
Keywords: ant colony algorithms, complex and dynamic systems, diagnosis, classification, optimizationProcedia PDF Downloads 227
123 Effectiveness of Working Memory Training on Cognitive Flexibility
Authors: Leila Maleki, Ezatollah Ahmadi
Abstract:The aim of this study was to investigate the effectiveness of memory training exercise on cognitive flexibility. The method of this study was experimental. The statistical population selected 40 students 14 years old, samples were chosen by available sampling method and then they were replaced in experimental (training program) group and control group randomly and answered to Wisconsin Card Sorting Test; covariance test results indicated that there were a significant in post-test scores of experimental group (p<0.005).
Keywords: cognitive flexibility, working memory exercises, problem solving, reaction timeProcedia PDF Downloads 351
122 Women's Concerns in Disasters at Family Level in Iranian Context
Authors: Maryam Nakhaei, Hamid Reza Khankeh, Mitra Moodi, Leila Daddoust
Abstract:Although individuals (men and women) experience disasters in different ways, because of important women’s roles in the family, we aim to shed more light on their issues in doing family. In this report, we present an overview of the main qualitative and quantitative findings of different projects have been conducted in the regions affected by disaster in Iran. This paper explores women’s needs and experiences after disaster at the family level in 'disaster response behavior', 'personal health' including reproductive health and needs of pregnant women, 'livelihood responsibilities', and 'marital relationships'. This clarification can help not only to ensure that their needs are adequately addressed but also to plan family based strategies which consider their strengths.
Keywords: disaster, family, women, IranProcedia PDF Downloads 235
121 Brain Age Prediction Based on Brain Magnetic Resonance Imaging by 3D Convolutional Neural Network
Authors: Leila Keshavarz Afshar, Hedieh Sajedi
Abstract:Estimation of biological brain age from MR images is a topic that has been much addressed in recent years due to the importance it attaches to early diagnosis of diseases such as Alzheimer's. In this paper, we use a 3D Convolutional Neural Network (CNN) to provide a method for estimating the biological age of the brain. The 3D-CNN model is trained by MRI data that has been normalized. In addition, to reduce computation while saving overall performance, some effectual slices are selected for age estimation. By this method, the biological age of individuals using selected normalized data was estimated with Mean Absolute Error (MAE) of 4.82 years.
Keywords: brain age estimation, biological age, 3D-CNN, deep learning, T1-weighted image, SPM, preprocessing, MRI, canny, gray matterProcedia PDF Downloads 77
120 Bioinsecticidal Activity and Phytochemical Study of the Crude Extract from the Plant Artemisia judaica
Authors: Fatma Acheuk, Idir Bitam, Leila Bendifallah, Malika Ramdani, Fethia Barika
Abstract:Phytochemical study of the plant Artemisia judaica showed the presence of various groups of natural products: saponins, tannins, coumarins, flavonoids, carbohydrates, and reducer compounds. However, alkaloids are present as traces. The crude ethanol extract of the test plant presented significant insecticidal activity on mosquito larvae in stage I, II and III. The LD50 highlighted the excellent insecticidal effect of the tested extract. Similarly, the LT50 are achieved early with high doses. The results obtained are encouraging and suggest the possibility of using the secondary metabolites of this plant such as bio-insecticide.
Keywords: Atamisia judaica, crud extract, mosquito, insecticidal activityProcedia PDF Downloads 425
119 Formulation of Extended-Release Ranolazine Tablet and Investigation Its Stability in the Accelerated Stability Condition at 40⁰C and 75% Humidity
Authors: Farzad Khajavi, Farzaneh Jalilfar, Faranak Jafari, Leila Shokrani
Abstract:Formulation of Ranolazine in the form of extended-release tablet in 500 mg dosage form was performed using Eudragit L100-55 as a retarding agent. Drug-release profiles were investigated in comparison with the reference Ranexa extended-release 500 mg tablet. F₂ and f₁ were calculated as 64.16 and 8.53, respectively. According to Peppas equation, the release of drug is controlled by diffusion (n=0.5). The tablets were put into accelerated stability conditions (40 °C, 75% humidity) for 3 and 6 months. The dissolution release profiles and other physical and chemical characteristics of the tablets confirmed the robustness and stability of formulation in this condition.
Keywords: drug release, extended-release tablet, ranolazine, stabilityProcedia PDF Downloads 76
118 Phytochemical Study and Bioinsecticidal Effect of the Crude Extract from the Plant Artemisia Judaica
Authors: Fatma Acheuk, Idir Bitam, Leila Bendifallah, Malika Ramdani, Fethia Barika
Abstract:Phytochemical study of the plant Artemisia judaica showed the presence of various groups of natural products: saponins, tannins, coumarins, flavonoids, carbohydrates, and reducer compounds. However alkaloids are present as traces. The crude ethanol extract of the test plant presented significant insecticidal activity on mosquito larvae in stage I, II, and III. The LD50 highlighted the excellent insecticidal effect of the tested extract. Similarly, the LT50 are achieved early with high doses. The results obtained are encouraging and suggest the possibility of using the secondary metabolites of this plant such as bio-insecticide.
Keywords: Atamisia judaica, crud extract, mosquito, insecticidal activityProcedia PDF Downloads 477
117 All-Optical Function Based on Self-Similar Spectral Broadening for 2R Regeneration in High-Bit-Rate Optical Transmission Systems
Authors: Leila Graini
Abstract:In this paper, we demonstrate basic all-optical functions for 2R regeneration (Re-amplification and Re-shaping) based on self-similar spectral broadening in low normal dispersion and highly nonlinear fiber (ND-HNLF) to regenerate the signal through optical filtering including the transfer function characteristics, and output extinction ratio. Our approach of all-optical 2R regeneration is based on those of Mamyshev. The numerical study reveals the self-similar spectral broadening very effective for 2R all-optical regeneration; the proposed design presents high stability compared to a conventional regenerator using SPM broadening with reduction of the intensity fluctuations and improvement of the extinction ratio.
Keywords: all-optical function, 2R optical regeneration, self-similar broadening, Mamyshev regeneratorProcedia PDF Downloads 121
116 Neuroplasticity: A Fresh Begining for Life
Authors: Leila Maleki, Ezatollah Ahmadi
Abstract:Neuroplasticity or the flexibility of the neural system is the ability of the brain to adapt to the lack or deterioration of sense and the capability of the neural system to modify itself through changing shape and function. Not only have studies revealed that neuroplasticity does not end in childhood, but also they have proven that it continues till the end of life and is not limited to the neural system and covers the cognitive system as well. In the field of cognition, neuroplasticity is defined as the ability to change old thoughts according to new conditions and the individuals' differences in using various styles of cognitive regulation inducing several social, emotional and cognitive outcomes. On the other hand, complexities of daily life necessitates cognitive neuroplasticity in order to adapt to different circumstances. The present paper attempts to discuss and define major theories and principles of neuroplasticity and elaborate on nature or nurture.
Keywords: neuroplasticity, cognitive plasticity, plasticity theories, plasticity mechanismsProcedia PDF Downloads 418
115 Neuroplasticity: A Fresh Beginning for Life
Authors: Leila Maleki, Ezatollah Ahmadi
Abstract:Neuroplasticity or the flexibility of the neural system is the ability of the brain to adapt to the lack or deterioration of sense and the capability of the neural system to modify itself through changing shape and function. Not only have studies revealed that neuroplasticity does not end in childhood, but also they have proven that it continues till the end of life and is not limited to the neural system and covers the cognitive system as well. In the field of cognition, neuroplasticity is defined as the ability to change old thoughts according to new conditions and the individuals' differences in using various styles of cognitive regulation inducing several social, emotional and cognitive outcomes. On the other hand, complexities of daily life necessitates cognitive neuroplasticity in order to adapt to different circumstances. The. present paper attempts to discuss and define major theories and principles of neuroplasticity and elaborate on nature or nurture.
Keywords: neuroplasticity, cognitive plasticity, plasticity theories, plasticity mechanismsProcedia PDF Downloads 384
114 Designing a Model for Measuring the Components of Good Governance in the Iranian Higher Education System
Authors: Maria Ghorbanian, Mohammad Ghahramani, Mahmood Abolghasemi
Abstract:Universities and institutions of higher education in Iran, like other higher education institutions in the world, have a heavy mission and task to educate students based on the needs of the country. Taking on such a serious responsibility requires having a good governance system for planning, formulating executive plans, evaluating, and finally modifying them in accordance with the current conditions and challenges ahead. In this regard, the present study was conducted with the aim of identifying the components of good governance in the Iranian higher education system by survey method and with a quantitative approach. In order to collect data, a researcher-made questionnaire was used, which includes two parts: personal and professional characteristics (5 questions) and the three components of good governance in the Iranian higher education system, including good management and leadership (8 items), continuous evaluation and effective (university performance, finance, and university appointments) (8 items) and civic responsibility and sustainable development (7 items). These variables were measured and coded in the form of a five-level Likert scale from "Very Low = 1" to "Very High = 5". First, the validity and reliability of the research model were examined. In order to calculate the reliability of the questionnaire, two methods of Cronbach's alpha and combined reliability were used. Fornell-Larker interaction and criterion were also used to determine the degree of diagnostic validity. The statistical population of this study included all faculty members of public universities in Tehran (N = 4429). The sample size was estimated to be 340 using the Cochran's formula. These numbers were studied using a randomized method with a proportional assignment. The data were analyzed by the structural equation method with the least-squares approach. The results showed that the component of civil responsibility and sustainable development with a factor load of 0.827 is the most important element of good governance.
Keywords: good governance, higher education, sustainable, developmentProcedia PDF Downloads 48
113 Valorization of Mining Waste (Sand of Djemi Djema) from the Djbel Onk Mine (Eastern Algeria)
Authors: Rachida Malaoui, Leila Arabet , Asma Benbouza
Abstract:The use of mining waste rock as a material for construction is one of the biggest concerns grabbing the attention of many mining countries. As these materials are abandoned, more effective solutions have been made to offset some of the building materials, and to avoid environmental pollution. The sands of the Djemi Djema deposit mines of the Djebel Onk mines are sedimentary materials of several varieties of layers with varying thicknesses and are worth far more than 300m deep. The sands from the Djemi Djema business area are medium to coarse and are discharged and accumulated, generating a huge estimated quantity of more than 77424250 tonnes. This state of "resource" is of great importance so as to be oriented towards the fields of public works and civil engineering after having reached the acceptable properties of this resource
Keywords: reuse, sands, shear tests, waste rockProcedia PDF Downloads 68
112 An Optimal Bayesian Maintenance Policy for a Partially Observable System Subject to Two Failure Modes
Authors: Akram Khaleghei Ghosheh Balagh, Viliam Makis, Leila Jafari
Abstract:In this paper, we present a new maintenance model for a partially observable system subject to two failure modes, namely a catastrophic failure and a failure due to the system degradation. The system is subject to condition monitoring and the degradation process is described by a hidden Markov model. A cost-optimal Bayesian control policy is developed for maintaining the system. The control problem is formulated in the semi-Markov decision process framework. An effective computational algorithm is developed and illustrated by a numerical example.
Keywords: partially observable system, hidden Markov model, competing risks, multivariate Bayesian controlProcedia PDF Downloads 384
111 Oxidation of Alcohols Types Using Nano-Graphene Oxide (NGO) as Heterogeneous Catalyst
Authors: Ali Gharib, Leila Vojdanifard, Nader Noroozi Pesyan, Mina Roshani
Abstract:We describe an efficient method for oxidation of alcohols to related aldehydes and ketones by hydrogen peroxide as oxidizing agent, under reflux conditions. Nano-graphene oxide (NGO) as a heterogeneous catalyst was used and had their activity compared with other various catalysts. This catalyst was found to be an excellent catalyst for oxidation of alcohols. The effects of various parameters, including catalyst type, nature of the substituent in the alcohols and temperature, on the yield of the carboxylic acids were studied. Nano-graphene oxide was synthesized by the oxidation of graphite powders. This nanocatalyst was found to be highly efficient in this reaction and products were obtained in good to excellent yields. The recovered nano-catalyst was successfully reused for several runs without significant loss in its catalytic activity.
Keywords: nano-graphene oxide, oxidation, aldehyde, ketone, catalystProcedia PDF Downloads 342
110 Study of Temperature and Precipitation Changes Based on the Scenarios (IPCC) in the Caspian Sea City: Case Study in Gillan Province
Authors: Leila Rashidian, Mina Rajabali
Abstract:Industrialization has made progress and comfort for human beings in many aspects. It is not only achievement for the global environment but also factor for destruction and disruption of the Earth's climate. In this study, we used LARS.WG model and down scaling of general circulation climate model HADCM-3 daily precipitation amounts, minimum and maximum temperature and daily sunshine hours. These data are provided by the meteorological organization for Caspian Sea coastal station such as Anzali, Manjil, Rasht, Lahijan and Astara since their establishment is from 1982 until 2010. According to the IPCC scenarios, including series A1b, A2, B1, we tried to simulate data from 2010 to 2040. The rainfall pattern has changed. So we have a rainfall distribution inappropriate in different months.
Keywords: climate change, Lars.WG, HADCM3, Gillan province, climatic parameters, A2 scenarioProcedia PDF Downloads 185
109 Optimal Production and Maintenance Policy for a Partially Observable Production System with Stochastic Demand
Authors: Leila Jafari, Viliam Makis
Abstract:In this paper, the joint optimization of the economic manufacturing quantity (EMQ), safety stock level, and condition-based maintenance (CBM) is presented for a partially observable, deteriorating system subject to random failure. The demand is stochastic and it is described by a Poisson process. The stochastic model is developed and the optimization problem is formulated in the semi-Markov decision process framework. A modification of the policy iteration algorithm is developed to find the optimal policy. A numerical example is presented to compare the optimal policy with the policy considering zero safety stock.
Keywords: condition-based maintenance, economic manufacturing quantity, safety stock, stochastic demandProcedia PDF Downloads 404
108 Study of the Effect of the Continuous Electric Field on the Rd Cancer Cell Line by Response Surface Methodology
Authors: Radia Chemlal, Salim Mehenni, Dahbia Leila Anes-boulahbal, Mohamed Kherat, Nabil Mameri
Abstract:The application of the electric field is considered to be a very promising method in cancer therapy. Indeed, cancer cells are very sensitive to the electric field, although the cellular response is not entirely clear. The tests carried out consisted in subjecting the RD cell line under the effect of the continuous electric field while varying certain parameters (voltage, exposure time, and cell concentration). The response surface methodology (RSM) was used to assess the effect of the chosen parameters, as well as the existence of interactions between them. The results obtained showed that the voltage, the cell concentration as well as the interaction between voltage and exposure time have an influence on the mortality rate of the RD cell line.
Keywords: continuous electric field, RD cancer cell line, RSM, voltageProcedia PDF Downloads 26
107 Ab Initio Spectroscopic Study of the Electronic Properties of the (Bana)+ Molecular Ion
Authors: Tahani H. Alluhaybi, Leila Mejrissi
Abstract:In the present theoretical study, we investigated adiabatically the electronic structure of the (BaNa)+ by the use of the ab initio calculation. We optimized a large atomic GTO basis set for Na and Ba atoms. The (BaNa)+ molecular ion is considered a two-electron thank to a non-empirical pseudo-potentials approach applied to Ba and Na cores with the Core Polarization Potentials operator (CPP). Then, we performed the Full Configuration Interaction (FCI) method. Accordingly, we calculated the adiabatic Potential Energy Curves (PECs) and their spectroscopic constants (well depth De, transition energies Te, the equilibrium distances Re, vibrational constant ⍵e, and anharmonic constant ⍵exe) for 10 electronic states in Σ+ symmetry. Then we determined the vibrational level energies and their spacing, and the electric Permanent Dipole Moments (PDM).
Keywords: Ab initio, dipole moment, non-empirical pseudo-potential, potential energy curves, spectroscopic constants, vibrational energyProcedia PDF Downloads 36
106 TMBCoI-SIOT: Trust Management System Based on the Community of Interest for the Social Internet of Things
Authors: Oumaima Ben Abderrahim, Mohamed Houcine Elhedhili, Leila Saidane
Abstract:In this paper, we propose a trust management system based on clustering architecture for the social internet of things called TMBCO-SIOT. The proposed model integrates numerous factors such as direct and indirect trust; transaction factor; precaution factor; and social modeling of trust. The novelty of our approach can be summed up in two aspects. The first aspect concerns the architecture based on the community of interest (CoT) where each community is headed by an administrator (admin). However, the second aspect is the trust management system that tries to prevent On-Off attacks and mitigates dishonest recommendations using the k-means algorithm and guarantor things. The effectiveness of the proposed system is proved by simulation against malicious nodes.
Keywords: IoT, trust management system, attacks, trust, dishonest recommendations, K-means algorithmProcedia PDF Downloads 154
105 Effects of Conjugated Linoleic Acid(CLA) on Some Reproductive Hormones in Ram
Authors: Behnaz Mahdavi, Hamidreza Khodaei, Leila Karshenas
Abstract:Conjugated Linoleic Acid is a group of long-chain unsaturated fatty acids with more than one double bond and a mixture of 28 isomers of Linoleic acid (C 18:2) and it is counted as one of the essential acids. The main purpose of this study was to investigate the effect of CLA on some reproductive hormones in rams. In this study, six rams 3 to 4 years old with an average weight of 90 kg were selected. Rams were randomly divided into 3 groups and were treated by CLA treatment for 30 days. The first group (as a control group) didn’t receive CLA, The second group received 0.5 gr and the third group received 1 gram of CLA. The blood testing was done on rams every 15 days using a 20 ml syringe. Data analysis was performed by SAS software. Also mean comparison was done using Duncan's test method (p<0.05). Obtained results showed that the serum concentration of testosterone hormone was decreased numerically as well as the concentration of FSH hormone however the concentration of LH was increased. CLA in oral form can reduce the concentration of testosterone in rams.
Keywords: CLA, ram, testosterone, DHT, Conjugated Linoleic AcidProcedia PDF Downloads 212
104 Simulation of Surface Runoff in Mahabad Dam Basin, Iran
Authors: Leila Khosravi
Abstract:A major part of the drinking water in North West of Iran is supplied from Mahabad reservoir 80 km northwest of Mahabad. This reservoir collects water from 750 km-catchment which is undergoing accelerated changes due to deforestation and urbanization. The main objective of this study is to develop a catchment modeling platform which translates ongoing land-use changes, soil data, precipitation and evaporation into surface runoﬀ of the river discharging into the reservoir: Soil and Water Assessment Tool, SWAT, model along with hydro -meteorological records of 1997–2011. A variety of statistical indices were used to evaluate the simulation results for both calibration and validation periods; among them, the robust Nash–Sutcliﬀe coeﬃcients were found to be 0.52 and 0.62 in the calibration and validation periods, respectively. This project has developed a reliable modeling platform with the benchmark land physical conditions of the Mahabad dam basin.
Keywords: simulation, surface runoff, Mahabad dam, SWAT modelProcedia PDF Downloads 127
103 Chest Pain as a Predictor for Heart Issues in Geriatrics
Authors: Leila Kargar, Homa Abri, Golsa Safai
Abstract:The occurrence of chest pain among geriatrics could be considered as a predictor of heart issues. There is a need for attention to this pain among this population. This review paper has tried to collect the recent data with attention to the chest pain among geriatrics. This review paper has focused on specific keywords, including chest pain, heart issues, and geriatrics, among published papers from 2015 till 2020. To collect data for this purpose, Scopus, Web of Sciences, and PubMed were used. After inserting related papers to the Endnote, an independent researcher checked the abstract, and papers with unclear methods or non-English language were excluded. Finally, 7-papers were included in this review paper. The findings of those papers showed that chest pain could be a predictor for heart issues, and also, there is a direct relationship between chest pain and heart issues among geriatrics. So, early detection and an accurate decision could be helpful to prevent heart issues in this population.
Keywords: pain, heart issue, geriatrics, healthProcedia PDF Downloads 147
102 Optimal Bayesian Control of the Proportion of Defectives in a Manufacturing Process
Authors: Viliam Makis, Farnoosh Naderkhani, Leila Jafari
Abstract:In this paper, we present a model and an algorithm for the calculation of the optimal control limit, average cost, sample size, and the sampling interval for an optimal Bayesian chart to control the proportion of defective items produced using a semi-Markov decision process approach. Traditional p-chart has been widely used for controlling the proportion of defectives in various kinds of production processes for many years. It is well known that traditional non-Bayesian charts are not optimal, but very few optimal Bayesian control charts have been developed in the literature, mostly considering finite horizon. The objective of this paper is to develop a fast computational algorithm to obtain the optimal parameters of a Bayesian p-chart. The decision problem is formulated in the partially observable framework and the developed algorithm is illustrated by a numerical example.
Keywords: Bayesian control chart, semi-Markov decision process, quality control, partially observable processProcedia PDF Downloads 254
101 Evaporative Air Coolers Optimization for Energy Consumption Reduction and Energy Efficiency Ratio Increment
Authors: Leila Torkaman, Nasser Ghassembaglou
Abstract:Significant quota of Municipal Electrical Energy consumption is related to Decentralized Air Conditioning which is mostly provided by evaporative coolers. So the aim is to optimize design of air conditioners to increase their efficiencies. To achieve this goal, results of practical standardized tests for 40 evaporative coolers in different types collected and simultaneously results for same coolers based on one of EER (Energy Efficiency Ratio) modeling styles are figured out. By comparing experimental results of different coolers standardized tests with modeling results, preciseness of used model is assessed and after comparing gained preciseness with international standards based on EER for cooling capacity, aeration and also electrical energy consumption, energy label from A (most effective) to G (less effective) is classified. finally needed methods to optimize energy consumption and cooler's classification are provided.
Keywords: cooler, EER, energy label, optimizationProcedia PDF Downloads 280
100 One-Pot Facile Synthesis of N-Doped Graphene Synthesized from Paraphenylenediamine as Metal-Free Catalysts for the Oxygen Reduction Used for Alkaline Fuel Cells
Authors: Leila Samiee, Amir Yadegari, Saeedeh Tasharrofi
Abstract:In the work presented here, nitrogen-doped graphene materials were synthesized and used as metal-free electrocatalysts for oxygen reduction reaction (ORR) under alkaline conditions. Paraphenylenediamine was used as N precursor. The N-doped graphene was synthesized under hydrothermal treatment at 200°C. All the materials have been characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM) and X-ray photo-electron spectroscopy (XPS). Moreover, for electrochemical evaluation of samples, Rotating Disk electrode (RDE) and Cyclic Voltammetry techniques (CV) were employed. The resulting material exhibits an outstanding catalytic activity for the oxygen reduction reaction (ORR) as well as excellent resistance towards methanol crossover effects, indicating their promising potential as ORR electrocatalysts for alkaline fuel cells.
Keywords: alkaline fuel cell, graphene, metal-free catalyst, paraphenylen diamineProcedia PDF Downloads 398
99 Degradation of Hydrocarbons by Surfactants and Biosurfactants
Authors: Samira Ferhat, Redha Alouaoui, Leila Trifi, Abdelmalek Badis
Abstract:The objective of this work is the use of natural surfactant (biosurfactant) and synthetic (sodium dodecyl sulfate and tween 80) for environmental application. In fact the solubility of the polycyclic hydrocarbon (naphthalene) and the desorption of the heavy metals in the presence of surfactants. The microorganisms selected in this work are bacterial strain (Bacillus licheniformis) for the production of biosurfactant for use in this study. In the first part of this study, we evaluated the effectiveness of surfactants solubilization certain hydrocarbons few soluble in water such as polyaromatic (case naphthalene). Tests have shown that from the critical micelle concentration, decontamination is performed. The second part presents the results on the desorption of heavy metals (for copper) by the three surfactants, using concentrations above the critical micelle concentration. The comparison between the desorption of copper by the three surfactants, it is shown that the biosurfactant is more effective than tween 80 and sodium dodecyl sulfate.
Keywords: surfactants, biosurfactant, naphthalene, copper, critical micelle concentration, solubilization, desorptionProcedia PDF Downloads 327