Search results for: middle wave infrared
2208 Measurement of Liquid Film Thickness in a Vertical Annular Two Phase Flow Changing the Gas-Liquid Density Ratio
Authors: Shoji Mori, Kunito Okuyama
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Annular two phase flow is encountered in many industrial equipments, including flow near nuclear fuel rods in boiling water reactor (BWR). Especially, disturbance waves play important roles in the pressure drop, the generation of entrainments, and the dryout of the liquid film. Therefore, it is important to clarify the behavior of disturbance waves and base film. However, most of the previous studies have been performed under atmospheric pressure conditions that provides the properties of liquid and gas which are significantly different from those of a BWR. Therefore, the effect of properties in gas and liquid on liquid film characteristics should be clarified. In this paper we focus on the effect of gas-liquid density ratio on liquid film thickness characteristics. The experiments have been conducted at four density ratio conditions (ρL/ρG =763, 451, 231, and 31). As a result, it is found that and interfacial shear stress collapse not only tF ave but also tF max and tF min successfully under the same liquid mass flow rate conditions irrespective of ρL/ρG, and moreover a non-dimensional parameter tends to collapse tF max,tF ave,and tF min in the wide range of experimental conditions (ρL/ρG:31~763,We:10~1800,ReL:500 ~ 2200).Keywords: two phase flow, liquid film, annular flow, disturbance wave
Procedia PDF Downloads 3882207 Impulsive Synchronization of Periodically Forced Complex Duffing's Oscillators
Authors: Shaban Aly, Ali Al-Qahtani, Houari B. Khenous
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Synchronization is an important phenomenon commonly observed in nature. A system of periodically forced complex Duffings oscillators was introduced and shown to display chaotic behavior and possess strange attractors. Such complex oscillators appear in many problems of physics and engineering, as, for example, nonlinear optics, deep-water wave theory, plasma physics and bimolecular dynamics. In this paper, we study the remarkable phenomenon of chaotic synchronization on these oscillator systems, using impulsive synchronization techniques. We derive analytical expressions for impulsive control functions and show that the dynamics of error evolution is globally stable, by constructing appropriate Lyapunov functions. This means that, for a relatively large set initial conditions, the differences between the drive and response systems vanish exponentially and synchronization is achieved. Numerical results are obtained to test the validity of the analytical expressions and illustrate the efficiency of these techniques for inducing chaos synchronization in our nonlinear oscillators.Keywords: complex nonlinear oscillators, impulsive synchronization, chaotic systems, global exponential synchronization
Procedia PDF Downloads 4472206 Effects of Heat Source Position on Heat Transfer in an Inclined Square Enclosure Filled with Nanofluids
Authors: Khamis Al Kalbani
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The effects of a uniform heat source position on the heat transfer flow inside an inclined square enclosure filled with different types of nanofluids having various shapes of the nanoparticles are investigated numerically following one component thermal equilibrium model. The effects of the Brownian diffusion of the nanoparticles, magnetic field intensity and orientation are taken into consideration in nanofluid modeling. The heat source is placed in the middle of a wall of the enclosure while the opposite wall of it is kept at different temperature. The other walls of the enclosure are kept insulated. The results indicate that the heat source position significantly controls the heat transfer rates of the nanofluids. The distributions of the average heat transfer rates varying the position of the heat source with respect to the geometry inclination angle are calculated for the first time. The outcomes of the present research may be helpful for designing solar thermal collectors, radiators, building insulators and advanced cooling of a nuclear system.Keywords: heat source, inclined, square enclosure, nanofluids
Procedia PDF Downloads 3052205 Software-Defined Radio Based Channel Measurement System of Wideband HF Communication System in Low-Latitude Region
Authors: P. H. Mukti, I. Kurniawati, F. Oktaviansyah, A. D. Adhitya, N. Rachmadani, R. Corputty, G. Hendrantoro, T. Fukusako
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HF Communication system is one of the attractive fields among many researchers since it can be reached long-distance areas with low-cost. This long-distance communication can be achieved by exploiting the ionosphere as a transmission medium for the HF radio wave. However, due to the dynamic nature of ionosphere, the channel characteristic of HF communication has to be investigated in order to gives better performances. Many techniques to characterize HF channel are available in the literature. However, none of those techniques describe the HF channel characteristic in low-latitude regions, especially equatorial areas. Since the ionosphere around equatorial region has an ESF phenomenon, it becomes an important investigation to characterize the wideband HF Channel in low-latitude region. On the other sides, the appearance of software-defined radio attracts the interest of many researchers. Accordingly, in this paper a SDR-based channel measurement system is proposed to be used for characterizing the HF channel in low-latitude region.Keywords: channel characteristic, HF communication system, LabVIEW, software-defined radio, universal software radio peripheral
Procedia PDF Downloads 4832204 Wave of Islamic Fintech: Revolutionizing Malaysia's Islamic Banking and Finance Regulatory Landscape
Authors: Ho Wen Hui, Azwina Wati Abdull Manaf, Asfarina Kartika Mohd Shakri
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The global trend of Fintech had taken the Malaysian shore by storm in recent years, thus making the studies and observations of its impacts more critical than ever. Additionally, Fintech has grown to become an unavoidable subject in the Islamic Banking and Finance (IBF) industry. In relation to that, this paper seeks to analyze the development of Fintech parallel with the IBF industry and its connection to Islamic economics. While the scarcity of studies on this area is apparent, it is found that there is a need to regulate the development of the Fintech Industry and its effects while analyzing the ramifications and positive effects of Fintech towards parties involved in IBF industry. This paper objectively studies the phenomenon of Islamic Fintech around the world as a whole as well as more specifically in Malaysia. The paper will then explore on the existing regulatory instruments in Malaysia, study their boundaries as well as limitations and contribute on possible reform to regulate Islamic Fintech in this jurisdiction. It is aimed that this paper will prompt and encourage more thorough studies to be conducted on the topic of Fintech which would subsequently contribute to a positive growth of the IBF industry worldwide.Keywords: financial technology, FinTech, Islamic banking & finance, regulation
Procedia PDF Downloads 2262203 A Content Analysis of Us Media Framing of Conflict: Effects on Global Journalism and Its Social Consequences
Authors: Lee Artz
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This presentation outlines US media frames of recent interventions in Iraq, Afghanistan, and Syria and their impact on global media and public discourse. A content analysis of sources, descriptors, and contexts of leading US media (AP, New York Times, Fox News) finds that news coverage highlights terrorism, justifies military action, and downplays the human costs. These media frames that normalize intervention also omit coverage of the environmental consequences of war, with scant or no reporting on pollution, destruction and contamination of agricultural infrastructures and the difficulty of any environmentally sustainable recovery. A content analysis of leading European and Middle East media (Daily Mail, Le Monde, Deutsch Welle, Al Jazeera) indicates that they have adopted the same reporting practices, frames, and techniques resulting in a hybrid, yet homogeneous, increasingly global news environment that does a disservice to the public interest and democracy.Keywords: conflict, environment, media framing, public interest
Procedia PDF Downloads 1982202 Machine Learning Approach for Anomaly Detection in the Simulated Iec-60870-5-104 Traffic
Authors: Stepan Grebeniuk, Ersi Hodo, Henri Ruotsalainen, Paul Tavolato
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Substation security plays an important role in the power delivery system. During the past years, there has been an increase in number of attacks on automation networks of the substations. In spite of that, there hasn’t been enough focus dedicated to the protection of such networks. Aiming to design a specialized anomaly detection system based on machine learning, in this paper we will discuss the IEC 60870-5-104 protocol that is used for communication between substation and control station and focus on the simulation of the substation traffic. Firstly, we will simulate the communication between substation slave and server. Secondly, we will compare the system's normal behavior and its behavior under the attack, in order to extract the right features which will be needed for building an anomaly detection system. Lastly, based on the features we will suggest the anomaly detection system for the asynchronous protocol IEC 60870-5-104.Keywords: Anomaly detection, IEC-60870-5-104, Machine learning, Man-in-the-Middle attacks, Substation security
Procedia PDF Downloads 3682201 Electro-Thermal Imaging of Breast Phantom: An Experimental Study
Authors: H. Feza Carlak, N. G. Gencer
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To increase the temperature contrast in thermal images, the characteristics of the electrical conductivity and thermal imaging modalities can be combined. In this experimental study, it is objected to observe whether the temperature contrast created by the tumor tissue can be improved just due to the current application within medical safety limits. Various thermal breast phantoms are developed to simulate the female breast tissue. In vitro experiments are implemented using a thermal infrared camera in a controlled manner. Since experiments are implemented in vitro, there is no metabolic heat generation and blood perfusion. Only the effects and results of the electrical stimulation are investigated. Experimental study is implemented with two-dimensional models. Temperature contrasts due to the tumor tissues are obtained. Cancerous tissue is determined using the difference and ratio of healthy and tumor images. 1 cm diameter single tumor tissue causes almost 40 °mC temperature contrast on the thermal-breast phantom. Electrode artifacts are reduced by taking the difference and ratio of background (healthy) and tumor images. Ratio of healthy and tumor images show that temperature contrast is increased by the current application.Keywords: medical diagnostic imaging, breast phantom, active thermography, breast cancer detection
Procedia PDF Downloads 4262200 Thermographic Tests of Curved GFRP Structures with Delaminations: Numerical Modelling vs. Experimental Validation
Authors: P. D. Pastuszak
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The present work is devoted to thermographic studies of curved composite panels (unidirectional GFRP) with subsurface defects. Various artificial defects, created by inserting PTFE stripe between individual layers of a laminate during manufacturing stage are studied. The analysis is conducted both with the use finite element method and experiments. To simulate transient heat transfer in 3D model with embedded various defect sizes, the ANSYS package is used. Pulsed Thermography combined with optical excitation source provides good results for flat surfaces. Composite structures are mostly used in complex components, e.g., pipes, corners and stiffeners. Local decrease of mechanical properties in these regions can have significant influence on strength decrease of the entire structure. Application of active procedures of thermography to defect detection and evaluation in this type of elements seems to be more appropriate that other NDT techniques. Nevertheless, there are various uncertainties connected with correct interpretation of acquired data. In this paper, important factors concerning Infrared Thermography measurements of curved surfaces in the form of cylindrical panels are considered. In addition, temperature effects on the surface resulting from complex geometry and embedded and real defect are also presented.Keywords: active thermography, composite, curved structures, defects
Procedia PDF Downloads 3172199 HPA Pre-Distorter Based on Neural Networks for 5G Satellite Communications
Authors: Abdelhamid Louliej, Younes Jabrane
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Satellites are becoming indispensable assets to fifth-generation (5G) new radio architecture, complementing wireless and terrestrial communication links. The combination of satellites and 5G architecture allows consumers to access all next-generation services anytime, anywhere, including scenarios, like traveling to remote areas (without coverage). Nevertheless, this solution faces several challenges, such as a significant propagation delay, Doppler frequency shift, and high Peak-to-Average Power Ratio (PAPR), causing signal distortion due to the non-linear saturation of the High-Power Amplifier (HPA). To compensate for HPA non-linearity in 5G satellite transmission, an efficient pre-distorter scheme using Neural Networks (NN) is proposed. To assess the proposed NN pre-distorter, two types of HPA were investigated: Travelling Wave Tube Amplifier (TWTA) and Solid-State Power Amplifier (SSPA). The results show that the NN pre-distorter design presents EVM improvement by 95.26%. NMSE and ACPR were reduced by -43,66 dB and 24.56 dBm, respectively. Moreover, the system suffers no degradation of the Bit Error Rate (BER) for TWTA and SSPA amplifiers.Keywords: satellites, 5G, neural networks, HPA, TWTA, SSPA, EVM, NMSE, ACPR
Procedia PDF Downloads 902198 Solid Dispersions of Cefixime Using β-Cyclodextrin: Characterization and in vitro Evaluation
Authors: Nagasamy Venkatesh Dhandapani, Amged Awad El-Gied
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Cefixime, a BCS class II drug, is insoluble in water but freely soluble in acetone and in alcohol. The aqueous solubility of cefixime in water is poor and exhibits exceptionally slow and intrinsic dissolution rate. In the present study, cefixime and β-Cyclodextrin (β-CD) solid dispersions were prepared with a view to study the effect and influence of β-CD on the solubility and dissolution rate of this poorly aqueous soluble drug. Phase solubility profile revealed that the solubility of cefixime was increased in the presence of β-CD and was classified as AL-type. Effect of variable, such as drug:carrier ratio, was studied. Physical characterization of the solid dispersion was characterized by Fourier transform infrared spectroscopy (FT-IR) and Differential scanning calorimetry (DSC). These studies revealed that a distinct loss of drug crystallinity in the solid molecular dispersions is ostensibly accounting for enhancement of dissolution rate in distilled water. The drug release from the prepared solid dispersion exhibited a first order kinetics. Solid dispersions of cefixime showed a 6.77 times fold increase in dissolution rate over the pure drug.Keywords: β-cyclodextrin, cefixime, dissolution, Kneading method, solid dispersions, release kinetics
Procedia PDF Downloads 3142197 Improvement and Miniaturization RFID Patch Antenna by Inclusion the Complementary Metamaterials
Authors: Seif Naoui, Lassaad Latrach, Ali Gharsallah
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This paper is specialized to highlight the method of miniaturization and improvement the patch antenna by using the complementary metamaterial. This method is presented by a simple technique is composed a structure of patch antenna integrated in its surface a cell of complementary split ring resonator. This resonator is placed at the middle of the radiating patch in parallel with the transmission line and with a variable angle of orientation. The objective is to find the ultimate angle where the best results are obtained on improving the characteristics of the considered antenna. This motif widespread at the traceability applications by wireless communication for RFID technology at the operation frequency 2.45 GHz. Our contribution is based on studies empirical often presented in this article. All simulation results were made by the CST Microwave Studio.Keywords: complimentary split ring resonators, computer simulation technology microwave studio, metamaterials patch antennas, microstrip patch antenna, radio frequency identification
Procedia PDF Downloads 4392196 Depolymerization of Lignin in Sugarcane Bagasse by Hydrothermal Liquefaction to Optimize Catechol Formation
Authors: Nirmala Deenadayalu, Kwanele B. Mazibuko, Lethiwe D. Mthembu
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Sugarcane bagasse is the residue obtained after the extraction of sugar from the sugarcane. The main aim of this work was to produce catechol from sugarcane bagasse. The optimization of catechol production was investigated using a Box-Behnken design of experiments. The sugarcane bagasse was heated in a Parr reactor at a set temperature. The reactions were carried out at different temperatures (100-250) °C, catalyst loading (1% -10% KOH (m/v)) and reaction times (60 – 240 min) at 17 bar pressure. The solid and liquid fractions were then separated by vacuum filtration. The liquid fraction was analyzed for catechol using high-pressure liquid chromatography (HPLC) and characterized for the functional groups using Fourier transform infrared spectroscopy (FTIR). The optimized condition for catechol production was 175 oC, 240 min, and 10 % KOH with a catechol yield of 79.11 ppm. Since the maximum time was 240 min and 10 % KOH, a further series of experiments were conducted at 175 oC, 260 min, and 20 % KOH and yielded 2.46 ppm catechol, which was a large reduction in catechol produced. The HPLC peak for catechol was obtained at 2.5 min for the standards and the samples. The FTIR peak at 1750 cm⁻¹ was due to the C=C vibration band of the aromatic ring in the catechol present for both the standard and the samples. The peak at 3325 cm⁻¹ was due to the hydrogen-bonded phenolic OH vibration bands for the catechol. The ANOVA analysis was also performed on the set of experimental data to obtain the factors that most affected the amount of catechol produced.Keywords: catechol, sugarcane bagasse, lignin, hydrothermal liquefaction
Procedia PDF Downloads 952195 On Enabling Miner Self-Rescue with In-Mine Robots using Real-Time Object Detection with Thermal Images
Authors: Cyrus Addy, Venkata Sriram Siddhardh Nadendla, Kwame Awuah-Offei
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Surface robots in modern underground mine rescue operations suffer from several limitations in enabling a prompt self-rescue. Therefore, the possibility of designing and deploying in-mine robots to expedite miner self-rescue can have a transformative impact on miner safety. These in-mine robots for miner self-rescue can be envisioned to carry out diverse tasks such as object detection, autonomous navigation, and payload delivery. Specifically, this paper investigates the challenges in the design of object detection algorithms for in-mine robots using thermal images, especially to detect people in real-time. A total of 125 thermal images were collected in the Missouri S&T Experimental Mine with the help of student volunteers using the FLIR TG 297 infrared camera, which were pre-processed into training and validation datasets with 100 and 25 images, respectively. Three state-of-the-art, pre-trained real-time object detection models, namely YOLOv5, YOLO-FIRI, and YOLOv8, were considered and re-trained using transfer learning techniques on the training dataset. On the validation dataset, the re-trained YOLOv8 outperforms the re-trained versions of both YOLOv5, and YOLO-FIRI.Keywords: miner self-rescue, object detection, underground mine, YOLO
Procedia PDF Downloads 792194 Development of pH Responsive Nanoparticles for Colon Targeted Drug Delivery System
Authors: V. Balamuralidhara
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The aim of the present work was to develop Paclitaxel loaded polyacrylamide grafted guar gum nanoparticles as pH responsive nanoparticle systems for targeting colon. The pH sensitive nanoparticles were prepared by modified ionotropic gelation technique. The prepared nanoparticles showed mean diameters in the range of 264±0.676 nm to 726±0.671nm, and a negative net charge 10.8 mV to 35.4mV. Fourier Transformed Infrared Spectroscopy (FT-IR) and Differential Scanning Calorimetry (DSC) studies suggested that there was no chemical interaction between drug and polymers. The encapsulation efficiency of the drug was found to be 40.92% to 48.14%. The suitability of the polyacrylamide grafted guar gum ERN’s for the release of Paclitaxel was studied by in vitro release at pH 1.2 and 7.4. It was observed that, there was no significant amount of drug release at gastric pH and 97.63% of drug release at pH 7.4 was obtained for optimized formulation F3 at the end of 12 hrs. In vivo drug targeting performance for the prepared optimized formulation (F3) and pure drug Paclitaxel was evaluated by HPLC. It was observed that the polyacrylamide grafted guar gum can be used to prepare nanoparticles for targeting the drug to the colon. The release performance was greatly affected by the materials used in ERN’s preparation, which allows maximum release at colon’s pH. It may be concluded that polyacrylamide grafted guar gum nanoparticles loaded with paclitaxel have desirable release responsive to specific pH. Hence it is a unique approach for colonic delivery of drug having appropriate site specificity and feasibility and controlled release of drug.Keywords: colon targeting, polyacrylamide grafted guar gum nanoparticles, paclitaxel, nanoparticles
Procedia PDF Downloads 3512193 Analyzing Time Lag in Seismic Waves and Its Effects on Isolated Structures
Authors: Faizan Ahmad, Jenna Wong
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Time lag between peak values of horizontal and vertical seismic waves is a well-known phenomenon. Horizontal and vertical seismic waves, secondary and primary waves in nature respectively, travel through different layers of soil and the travel time is dependent upon the medium of wave transmission. In seismic analysis, many standardized codes do not require the actual vertical acceleration to be part of the analysis procedure. Instead, a factor load addition for a particular site is used to capture strength demands in case of vertical excitation. This study reviews the effects of vertical accelerations to analyze the behavior of a linearly rubber isolated structure in different time lag situations and frequency content by application of historical and simulated ground motions using SAP2000. The response of the structure is reviewed under multiple sets of ground motions and trends based on time lag and frequency variations are drawn. The accuracy of these results is discussed and evaluated to provide reasoning for use of real vertical excitations in seismic analysis procedures, especially for isolated structures.Keywords: seismic analysis, vertical accelerations, time lag, isolated structures
Procedia PDF Downloads 3322192 Changing Faces of the Authoritarian Reflex and Islamist Actors in the Maghreb and Mashreq after Arab Uprisings
Authors: Nur Köprülü
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One of the main questions that have arisen after the Arab uprisings has centered on whether they will lead to democratic transition and what the roles of Islamist actors will be. It has become apparent today that one of the key outcomes has been the partial, if not total, overthrow of authoritarian regimes in some cases. So, this article aims to analyse three synchronous upshots brought about by the uprisings, referring to patterns of state formation in the Maghreb and Mashreq. One of the main outcomes has been the persistence of authoritarianism in various forms, and the fragility of the Arab republics coping with the protests as compared to the more resilient character of the monarchies. In addition, none of the uprisings has brought an Islamist organization to incontestable power, as some predicted. However, ‘old’ Islamist actors have since re-emerged as key players, namely the Muslim Brotherhood in Tunisia, Egypt, Jordan and elsewhere. Thus, to understand the synthesis of change and continuity in the Middle East in the aftermath of the Arab Spring, analysing the changing faces of authoritarianism in the region and the impact on Islamists in both the Maghreb and the Mashreq is imperative.Keywords: authoritarianism, democratization, Arab spring, Islamists
Procedia PDF Downloads 2192191 A Particle Image Velocimetric (PIV) Experiment on Simplified Bottom Hole Flow Field
Authors: Heqian Zhao, Huaizhong Shi, Zhongwei Huang, Zhengliang Chen, Ziang Gu, Fei Gao
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Hydraulics mechanics is significantly important in the drilling process of oil or gas exploration, especially for the drill bit. The fluid flows through the nozzles on the bit and generates a water jet to remove the cutting at the bottom hole. In this paper, a simplified bottom hole model is established. The Particle Image Velocimetric (PIV) is used to capture the flow field of the single nozzle. Due to the limitation of the bottom and wellbore, the potential core is shorter than that of the free water jet. The velocity magnitude rapidly attenuates when fluid close to the bottom is lower than about 5 mm. Besides, a vortex zone appears near the middle of the bottom beside the water jet zone. A modified exponential function can be used to fit the centerline velocity well. On the one hand, the results of this paper can provide verification for the numerical simulation of the bottom hole flow field. On the other hand, it also can provide an experimental basis for the hydraulic design of the drill bit.Keywords: oil and gas, hydraulic mechanic of drilling, PIV, bottom hole
Procedia PDF Downloads 2112190 Labor Migration: An Anthropological Study of Migrants Socio-Economic Development and Exploitation
Authors: Usman Khan
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The article discusses mass migration, which has been a problem throughout history. People moved for a variety of reasons, including better job opportunities, prosperous, healthy lifestyles, and other basic needs. This research focuses on the issues and challenges that immigrants face when they arrive at their destination countries especially Saudi Arab. Among these issues are the Kapala system, irregular salaries, living conditions, document seizure, and so on. The primary data sources for this qualitative anthropological study include in-depth interviews and focus group discussions (FGDs). The research was carried out in the villages of Zulam and Shagokas in Khyber Pakhtunkhwa's Dir Lower District. The article concludes by stating that the agents and employers treated labor migrants/workers inhumanely. Throughout the process, they have been subjected to severe exploitation and suffering. Finally, the migrants sent back remittances that aided the region's economic and infrastructure development.Keywords: Migration, Exploitation, labour, Middle East, Kafala and Tanazol System.
Procedia PDF Downloads 732189 Conductometric Methanol Microsensor Based on Electrospun PVC-Nickel Phthalocyanine Composite Nanofiber Technology
Authors: Ibrahim Musa, Guy Raffin, Marie Hangouet, Nadia Zine, Nicole Jaffrezic-Renault, Abdelhamid Errachid
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Due to its application in different domains, such as fuel cell configuration and adulteration of alcoholic beverages, a miniaturized sensor for methanol detection is urgently required. A conductometric microsensor for measuring volatile organic compounds (VOC) was conceived, based on electrospun composite nanofibers of polyvinyl chloride (PVC) doped with nickel phthalocyanine(NiPc) deposited on interdigitated electrodes (IDEs) used transducers. The nanofiber's shape, structure, percent atomic content and thermal properties were studied using analytical techniques, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), respectively. The methanol sensor showed good sensitivity (505µS/cm(v/v) ⁻¹), low LOD (15 ppm), short response time (13 s), and short recovery time (15 s). The sensor was 4 times more sensitive to methanol than to ethanol and 19 times more sensitive to methanol than to acetone. Furthermore, the sensor response was unaffected by the interfering water vapor, making it more suitable for VOC sensing in the presence of humidity. The sensor was applied for conductometric detection of methanol in rubbing alcohol.Keywords: composite, methanol, conductometric sensor, electrospun, nanofiber, nickel phthalocyanine, PVC
Procedia PDF Downloads 202188 Spectroscopic Determination of Functionalized Active Principles from Coleus aromaticus Benth Leaf Extract Using Ionic Liquids
Authors: Zharama M. Llarena
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Green chemistry for plant extraction of active principles is the main interest of many researchers concerned with climate change. While classical organic solvents are detrimental to our environment, greener alternatives to ionic liquids are very promising for sustainable organic chemistry. This study focused on the determination of functional groups observed in the main constituents from the ionic liquid extracts of Coleus aromaticus Benth leaves using FT-IR Spectroscopy. Moreover, this research aimed to determine the best ionic liquid that can separate functionalized plant constituents from the leaves Coleus aromaticus Benth using Fourier Transform Infrared Spectroscopy. Coleus aromaticus Benth leaf extract in different ionic liquids, elucidated pharmacologically important functional groups present in major constituents of the plant, namely, rosmarinic acid, caffeic acid and chlorogenic acid. In connection to distinctive appearance of functional groups in the spectrum and highest % transmittance, potassium chloride-glycerol is the best ionic liquid for green extraction.Keywords: chlorogenic acid, coleus aromaticus, ionic liquid, rosmarinic acid
Procedia PDF Downloads 3172187 Skew Planar Wheel Antenna for First Person View of Unmanned Aerial Vehicle
Authors: Raymond Yudhi Purba, Levy Olivia Nur, Radial Anwar
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This research presents the design and measurement of a skew planar wheel antenna that is used to visualize the first person view perspective of unmanned aerial vehicles. The antenna has been designed using CST Studio Suite 2019 to have voltage standing wave ratio (VSWR) ≤ 2, return loss ≤ -10 dB, bandwidth ≥ 100 MHz to covering outdoor access point band from 5.725 to 5.825 GHz, omnidirectional radiation pattern, and elliptical polarization. Dimensions of skew planar wheel antenna have been modified using parameter sweep technique to provide good performances. The simulation results provide VSWR 1.231, return loss -19.693 dB, bandwidth 828.8 MHz, gain 3.292 dB, and axial ratio 9.229 dB. Meanwhile, the measurement results provide VSWR 1.237, return loss -19.476 dB, bandwidth 790.5 MHz, gain 3.2034 dB, and axial ratio 4.12 dB.Keywords: skew planar wheel, cloverleaf, first-person view, unmanned aerial vehicle, parameter sweep
Procedia PDF Downloads 2142186 The Determinants of Behavioral Intention to Use toward T-Cash Services Provider in Jakarta and Surburban Area
Authors: Stephen Coandadiputra, Chrestella Carissa
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Technology is created to simplify human’s life. One of current technology which being called as the second wave internet generation is the internet of things. Internet of things lets thousands of devices connected each other. In today's marketing world, IOT has brought customer into the next level which helping the customer to shorten every transaction they are conducting from traditional approach to sophisticated approach. However, the implementation of technology has always obstacles. The objective of this paper is to explore the determinants of customer to accepts such technology like the internet of things within their transaction. According to TAM (Technology Acceptance Model), researcher constructs the acceptance of internet of things based on perceived usefulness, perceived ease of use and trust and social factor and the two customer characteristics: perceived enjoyment and perceived behavioral control. This research uses exploratory research design which being facilitated by spreading questionnaire to 145 T-cash users in Jakarta and in its suburban region. At least, 190 samples were observed and questioned accordingly. All the collected data will be analyzed using Lisrel.Keywords: behavioral intention to use, internet of things, near field communication, technology acceptance model
Procedia PDF Downloads 3332185 White Light Emission through Downconversion of Terbium and Europium Doped CEF3 Nanophosphors
Authors: Mohit Kalra, Varun S., Mayuri Gandhi
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CeF3 nanophosphors has been extensively investigated in the recent years for lighting and numerous bio-applications. Down conversion emissions in CeF3:Eu3+/Tb3+ phosphors were studied with the aim of obtaining a white light emitting composition, by a simple co-precipitation method. The material was characterized by X-ray Diffraction (XRD), High Resolution Transmission Electron Microscopy (HR-TEM), Fourier Transform Infrared Spectroscopy (FT-IR) and Photoluminescence (PL). Uniformly distributed nanoparticles were obtained with an average particle size 8-10 nm. Different doping concentrations were performed and fluorescence study was carried out to optimize the dopants concentration for maximum luminescence intensity. The steady state and time resolved luminescence studies confirmed efficient energy transfer from the host to activator ions. Different concentrations of Tb 3+, Eu 3+ were doped to achieve a white light emitting phosphor for UV-based Light Emitting Diodes (LEDs). The nanoparticles showed characteristic emission of respective dopants (Eu 3+, Tb3+) when excited at the 4f→5d transition of Ce3+. The chromaticity coordinates for these samples were calculated and the CeF3 doped with Eu 3+ and Tb3+ gave an emission very close to white light. These materials may find its applications in optoelectronics and various bio applications.Keywords: white light down-conversion, nanophosphors, LEDs, rare earth, cerium fluoride, lanthanides
Procedia PDF Downloads 4042184 Effect of Multi Walled Carbon Nanotubes on Pyrolysis Behavior of Unsaturated Polyester Resin
Authors: Rosli Mohd Yunus, A. K. M. Moshiul Alam, Mohammad Dalour Beg
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In the case of advance polymeric materials reinforcement and thermal stability of matrix is a focused arena of researchers. The distribution of carbon nanotubes (CNTs) in polymer matrix influences material properties. In this study, multi-walled carbon nanotubes (MWCNTs) have been dispersed in unsaturated polyester resin (UPR) through solution mixing and sonication techniques using tetra hydro furan (THF) solvent. Nanocomposites have been fabricated with solution mixing and without solution mixing. Viscosity, Fourier-transform infrared spectroscopy, Field emission scanning electron microscopy (FESEM) investigations have been conducted to study the distribution as well as interaction between matrix and MWCNT. The differential scanning calorimetry (DSC), thermogravimetric analyses (TGA) and pyrolysis behavior have been conducted to study the thermal degradation and stability of nanocomposites. In addition, the SEM micrographs of nanocomposite residual chars were exhibited more packed together. Incorporation of CNT enhances crystallinity and mechanical and thermal properties of the nanocomposites. Correlations among MWCNTs dispersion, nucleation, fracture morphology and various properties have been made.Keywords: char, multiwall carbon nanotubes, nano composite, pyrolysis
Procedia PDF Downloads 3592183 Heat Waves Effect on Stock Return and Volatility: Evidence from Stock Market and Selected Industries in Pakistan
Authors: Sayed Kifayat Shah, Tang Zhongjun, Arfa Tanveer
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This study explores the significant heatwave effect on stock return and volatility. Using an ARCH/GARCH approach, it examines the relationship between the heatwave of Karachi, Islamabad, and Lahore on the KSE-100 index. It also explores the impact of heatwave on returns of the pharmaceutical and electronics industries. The empirical results confirm that that stock return is positively related to the heat waves of Karachi, negatively related to that of Islamabad, and is not affected by the heatwave of Lahore. Similarly, pharmaceutical and electronics indices are also positively related to heatwaves. These differences in results can be ascribed to the change in the behavior of the residents of that city. The outcomes are useful for understanding an investor's behavior reacting to weather and fluxes in stock price related to heatwave severity levels. The results can support investors in fixing biases in behavior.Keywords: ARCH/GARCH model, heat wave, KSE-100 index, stock market return
Procedia PDF Downloads 1542182 Cellulose Acetate/Polyacrylic Acid Filled with Nano-Hydroxapatite Composites: Spectroscopic Studies and Search for Biomedical Applications
Authors: E. M. AbdelRazek, G. S. ElBahy, M. A. Allam, A. M. Abdelghany, A. M. Hezma
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Polymeric biocomposite of hydroxyapatite/polyacrylic acid were prepared and their thermal and mechanical properties were improved by addition of cellulose acetate. FTIR spectroscopy technique and X-ray diffraction analysis were employed to examine the physical and chemical characteristics of the biocomposites. Scanning electron microscopy shows a uniform distribution of HAp nano-particles through the polymeric matrix of two organic/inorganic composites weight ratios (60/40 and 70/30), at which the material crystallinity reaches a considerable value appropriate for the needed applications were studied and revealed that the HAp nano-particles are uniformly distributed in the polymeric matrix. Kinetic parameters were determined from the weight loss data using non isothermal thermogravimetric analysis (TGA). Also, the main degradation steps were described and discussed. The mechanical properties of composites were evaluated by measuring tensile strength and elastic modulus. The data indicate that the addition of cellulose acetate can make homogeneous composites scaffold significantly resistant to higher stress. Elastic modulus of the composites was also improved by the addition of cellulose acetate, making them more appropriate for bioapplications.Keywords: biocomposite, chemical synthesis, infrared spectroscopy, mechanical properties
Procedia PDF Downloads 4562181 Perception of Consumer Behavior on Mobile Banking Offered by the National and Multinational Banks in UAE with Special Reference to Emirates NBD and Citibank
Authors: Aarohi Surya
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The number of mobile banking users continues to climb across the world due to its increasing popularity, and UAE is no exception. This type of banking is part of the core strategy of most of the financial institutions that allows its customers to conduct a range of financial transactions through mobile apps to cash in the high demand from the bankers. This study aims at evaluating service quality of online banking in Dubai, one of the swiftly growing cities of Middle East. The paper mainly compares online banking services of Multinational bank and National Bank with special reference to Citibank and Emirates NBD. A structured questionnaire survey is conducted among various target groups. The research has been focused on mainly 4 significant areas of online banking, i.e. Privacy, Responsiveness, Reliability, and Efficiency of customer data. Information was analyzed statistically on SPSS to investigate the service quality of e-banking.Keywords: customer satisfaction, service quality, responsiveness, online banking
Procedia PDF Downloads 2702180 Spectroscopic, Molecular Structure and Electrostatic Potential, Polarizability, Hyperpolarizability, and HOMO–LUMO Analysis of Monomeric and Dimeric Structures of N-(2-Methylphenyl)-2-Nitrobenzenesulfonamide
Authors: A. Didaoui, N. Benhalima, M. Elkeurti, A. Chouaih, F. Hamzaoui
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The monomer and dimer structures of the title molecule have been obtained from density functional theory (DFT) B3LYP method with 6-31G (d,p) as basis set calculations. The optimized geometrical parameters obtained by B3LYP/6-31G (d,p) method show good agreement with xperimental X-ray data. The polarizability and first order hyperpolarizabilty of the title molecule were calculated and interpreted. the intermolecular N–H•••O hydrogen bonds are discussed in dimer structure of the molecule. The vibrational wave numbers and their assignments were examined theoretically using the Gaussian 03 set of quantum chemistry codes. The predicted frontier molecular orbital energies at B3LYP/6-31G(d,p) method set show that charge transfer occurs within the molecule. The frontier molecular orbital calculations clearly show the inverse relationship of HOMO–LUMO gap with the total static hyperpolarizability. The results also show that N-(2-Methylphenyl)-2-nitrobenzenesulfonamide molecule may have nonlinear optical (NLO) comportment with non-zero values.Keywords: DFT, Gaussian 03, NLO, N-(2-Methylphenyl)-2-nitrobenzenesulfonamide
Procedia PDF Downloads 5492179 Stream Channel Changes in Balingara River, Sulawesi Tengah
Authors: Muhardiyan Erawan, Zaenal Mutaqin
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Balingara River is one of the rivers with the type Gravel-Bed in Indonesia. Gravel-Bed Rivers easily deformed in a relatively short time due to several variables, that are climate (rainfall), river discharge, topography, rock types, and land cover. To determine stream channel changes in Balingara River used Landsat 7 and 8 and analyzed planimetric or two dimensions. Parameters to determine changes in the stream channel are sinuosity ratio, Brice Index, the extent of erosion and deposition. Changes in stream channel associated with changes in land cover then analyze with a descriptive analysis of spatial and temporal. The location of a stream channel has a low gradient in the upstream, and middle watershed with the type of rock in the form of gravel is more easily changed than other locations. Changes in the area of erosion and deposition influence the land cover changes.Keywords: Brice Index, erosion, deposition, gravel-bed, land cover change, sinuosity ratio, stream channel change
Procedia PDF Downloads 326