Search results for: thermal characterization
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5680

Search results for: thermal characterization

2590 Hafnium and Samarium Hydroxyapatite Composites and Their Characterization

Authors: Meltem Nur Erdöl, Feyzanur Bayrak, Elif Emanetçi, Faik Nüzhet Oktar, Cevriye Kalkandelen, Oğuzhan Gündüz

Abstract:

Nowadays, the bioceramic graft applications are very important due to the fact that especially European population is getting much older. Consequently, healing approaches for some health problems become more important in the near future. For instance, osteoporosis is one of the reasons for serious hip fractures. Beside these, the traffic accidents playing role increasing of various hip fractures and other bone fractures. Naturally all these are leading the importance developing new bioceramic graft materials. Hydroxyapatite (HA) is one of the leading bioceramics on the market. Beside the high biocompatibility HA bioceramics unfortunately are weak materials for loaded areas. For improvement mechanical properties of HA material, some oxides and metallic powders can be added. In this study, some rare earth oxides like hafnium (IV) oxide (HfO₂) and samarium (III) oxide (Sm₂O₃) are added to HA for improvement of their material characteristics. Thus, compression, microhardness and theoretical density tests are performed. X-ray diffraction patterns are also investigated corresponding x-ray diffraction equipment. At the end, studies of scanning electron microscope (SEM) and energy-dispersive x-ray spectroscopy (EDX) are completed. All values were compared with past BHA and various composites.

Keywords: biocomposite, hafnium oxide, hydroxyapatite, nanotechnology, samarium oxide

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2589 Modelling of Lunar Lander’s Thruster’s Exhaust Plume Impingement in Vacuum

Authors: Mrigank Sahai, R. Sri Raghu

Abstract:

This paper presents the modelling of rocket exhaust plume flow field and exhaust plume impingement in vacuum for the liquid apogee engine and attitude control thrusters of the lunar lander. Analytic formulations for rarefied gas kinetics has been taken as reference for modelling the plume flow field. The plume has been modelled as high speed, collision-less, axi-symmetric gas jet, expanding into vacuum and impinging at a normally set diffusive circular plate. Specular reflections have not been considered for the present study. Different parameters such as number density, temperature, pressure, flow velocity, heat flux etc., have been calculated and have been plotted against and compared to Direct Simulation Monte Carlo results. These analyses have provided important information for the placement of critical optical instruments and design of optimal thermal insulation for the hardware that may come in contact with the thruster exhaust.

Keywords: collision-less gas, lunar lander, plume impingement, rarefied exhaust plume

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2588 Characterization of Calcined Clay Blended Self Compacting Concrete-Correlation between Super-Plasticizer Dosage and Self Compacting Concrete Properties

Authors: Kumator Josiphiah Taku

Abstract:

Sustainability in construction is essential to the economic construction and can be achieved by the use of locally available construction materials. This research work, thus, uses locally available materials –calcined clay and Sandcrete SPR-300 superplasticizer in the production of Self Compacting Concrete (SCC) by investigating the correlation between the superplasticizer dosage and the fresh and hardened states properties of a grade 50 SCC made by incorporating a Calcined Clay (CC) – Portland Limestone Cement (PLC) blend as the cementitious matter at 20% replacement of PLC with CC and using CC as filler. The superplasticizer dosage was varied from 0.4 to 3.0% by weight of cementitious material and the slump, v-funnel, L-box and strength parameters investigated. The result shows a positive correlation between the increased dosage of the superplasticizer and the fresh and hardened states properties of the SCC up to 2% dosage. The J¬Spread¬, t¬500J¬, Slump flow, L-box H¬2¬/H¬1 ¬ratio and strength, all increases with SP dosage while the V-funnel flow decreased with SP dosage. Overall, SP ratio of 0.5 to 2.0 can be used in improving the properties of SCC produced using calcined clay both as filler and cementitious material.

Keywords: calcined clay, compressive strength, fresh-state properties of SCC, self compacting concrete, superplasticizer dosage

Procedia PDF Downloads 154
2587 Wireless Capsule Endoscope - Antenna and Channel Characterization

Authors: Mona Elhelbawy, Mac Gray

Abstract:

Traditional wired endoscopy is an intrusive process that requires a long flexible tube to be inserted through the patient’s mouth while intravenously sedated. Only images of the upper 4 feet of stomach, colon, and rectum can be captured, leaving the remaining 20 feet of small intestines. Wireless capsule endoscopy offers a painless, non-intrusive, efficient and effective alternative to traditional endoscopy. In wireless capsule endoscopy (WCE), ingestible vitamin-pill-shaped capsules with imaging capabilities, sensors, batteries, and antennas are designed to send images of the gastrointestinal (GI) tract in real time. In this paper, we investigate the radiation performance and specific absorption rate (SAR) of a miniature conformal capsule antenna operating at the Medical Implant Communication Service (MICS) frequency band in the human body. We perform numerical simulations using the finite element method based commercial software, high-frequency structure simulator (HFSS) and the ANSYS human body model (HBM). We also investigate the in-body channel characteristics between the implantable capsule and an external antenna placed on the surface of the human body.

Keywords: IEEE 802.15.6, MICS, SAR, WCE

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2586 Characterization of Coronary Artery Obstruction and Related Findings in Ischemic Heart Patients Using Cardiac Scintigraphy

Authors: Yousif Mohamed Y. Abdallah, Eltayeb Wagi Allah Eltayeb, Mohamed E. Gar-elnabi, Mohamed Ahmed Ali

Abstract:

To characterize coronary artery obstruction and related findings in ischemic heart patients using cardiac scintigraphy for the identification of myocardial ischemia, 146 patients were studied at basal conditions and also asked for fasting after night till the intravenous injection of the radiopharmaceutical. After the injection time about 15 to 20 minutes, the patient should eat a fatty meal and chocolate for the good excretion of the gall bladder, to evaluate the performance and regional wall motion of the left ventricle (LV). The results showed that the body mass index percentage in this sample was in range of 43.05 to 61.05. The number of patients who were catheter candidates were 56 with 43% and the patients that were not candidate to cathode were 74 patients with 57% of all patients. For the group of patients where type of ischemia was assessed, 29.5% of patients had reversible posterior and inferior wall, 15.1% of patients had fixed large from apex to base, 9.6% of patients had mild basal inferior wall, 4.8 % of patients had mild anterior wall, 6.2% of patients had antro-septal and 34.9% of patients had moderate ischemia.

Keywords: myocardial ischemia, myocardial scintigraphy, contrast ventriculography, coronary artery obstruction

Procedia PDF Downloads 579
2585 Estimation of Fuel Cost Function Characteristics Using Cuckoo Search

Authors: M. R. Al-Rashidi, K. M. El-Naggar, M. F. Al-Hajri

Abstract:

The fuel cost function describes the electric power generation-cost relationship in thermal plants, hence, it sheds light on economical aspects of power industry. Different models have been proposed to describe this relationship with the quadratic function model being the most popular one. Parameters of second order fuel cost function are estimated in this paper using cuckoo search algorithm. It is a new population based meta-heuristic optimization technique that has been used in this study primarily as an accurate estimation tool. Its main features are flexibility, simplicity, and effectiveness when compared to other estimation techniques. The parameter estimation problem is formulated as an optimization one with the goal being minimizing the error associated with the estimated parameters. A case study is considered in this paper to illustrate cuckoo search promising potential as a valuable estimation and optimization technique.

Keywords: cuckoo search, parameters estimation, fuel cost function, economic dispatch

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2584 Impact of Fly Ash-Based Geopolymer Modification on the High-Temperature Properties of Bitumen

Authors: Burak Yigit Katanalp, Murat Tastan, Perviz Ahmedzade, çIgdem Canbay Turkyilmaz, Emrah Turkyilmaz

Abstract:

This study evaluated the mechanical and rheological performance of fly ash-based geopolymer at high temperatures. A series of laboratory tests were conducted on neat bitumen and three modified bitumen samples, which incorporated fly ash-based geopolymer at various percentages. Low-calcium fly ash was used as the alumina-silica source. The dynamic shear rheometer and rotational viscometer were employed to determine high-temperature properties, while conventional tests such as penetration and softening point were used to evaluate the physical properties of bitumen. The short-term aging resistance of the samples was assessed using the rolling thin film oven. The results show that geopolymer has a compromising effect on bitumen properties, with improved stiffness, enhanced mechanical strength, and increased thermal susceptibility of the asphalt binder.

Keywords: bitumen, geopolymer, modification, dynamic mechanical analysis

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2583 Proposal of Methodology Based on Technical Characterization and Quantitative Contrast of Co₂ Emissions for the Migration to Electric Mobility of the Vehicle Fleet: Case Study of Electric Companies in Ecuador

Authors: Rodrigo I. Ullauri, Santiago E. Tinajero, Omar O. Ramos, Paola R. Quintana

Abstract:

The increase of CO₂ emissions in the atmosphere and its impact on climate change is a global concern. The transportation sector is a significant consumer of fossil fuels and contributes significantly to greenhouse gas emissions. The current challenge is to find ways to reduce the use of fossil fuels in transportation. In Ecuador, where 92% of electricity is generated from clean sources, the concept of e-mobility is considered an attractive alternative to address the challenge of sustainable mobility. The proposal is to migrate from combustion-powered vehicles to electric vehicles in the electric companies of Ecuador, using a methodology to standardize criteria, determine specific requirements, contrast technical characteristics, and estimate emission reductions. The results showed that there are three categories of vehicles that have electric counterparts suitable for performing activities under certain operation parameters inherent to current technology limitations but with a significant contribution to the reduction of annual CO₂ emissions.

Keywords: climate change, electro mobility, energy, sustainable transportation

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2582 The Cadmium Adsorption Study by Using Seyitomer Fly Ash, Diatomite and Molasses in Wastewater

Authors: N. Tugrul, E. Moroydor Derun, E. Cinar, A. S. Kipcak, N. Baran Acarali, S. Piskin

Abstract:

Fly ash is an important waste, produced in thermal power plants which causes very important environmental pollutions. For this reason the usage and evaluation the fly ash in various areas are very important. Nearly, 15 million tons/year of fly ash is produced in Turkey. In this study, usage of fly ash with diatomite and molasses for heavy metal (Cd) adsorption from wastewater is investigated. The samples of Seyitomer region fly ash were analyzed by X-ray fluorescence (XRF) and Scanning Electron Microscope (SEM) then diatomite (0 and 1% in terms of fly ash, w/w) and molasses (0-0.75 mL) were pelletized under 30 MPa of pressure for the usage of cadmium (Cd) adsorption in wastewater. After the adsorption process, samples of Seyitomer were analyzed using Optical Emission Spectroscopy (ICP-OES). As a result, it is seen that the usage of Seyitomer fly ash is proper for cadmium (Cd) adsorption and an optimum adsorption yield with 52% is found at a compound with Seyitomer fly ash (10 g), diatomite (0.5 g) and molasses (0.75 mL) at 2.5 h of reaction time, pH:4, 20ºC of reaction temperature and 300 rpm of stirring rate.

Keywords: heavy metal, fly ash, molasses, diatomite, adsorption, wastewater

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2581 The Effect of Fly Ash in Dewatering of Marble Processing Wastewaters

Authors: H. A. Taner, V. Önen

Abstract:

In the thermal power plants established to meet the energy need, lignite with low calorie and high ash content is used. Burning of these coals results in wastes such as fly ash, slag and flue gas. This constitutes a significant economic and environmental problems. However, fly ash can find evaluation opportunities in various sectors. In this study, the effectiveness of fly ash on suspended solid removal from marble processing wastewater containing high concentration of suspended solids was examined. Experiments were carried out for two different suspensions, marble and travertine. In the experiments, FeCl3, Al2(SO4)3 and anionic polymer A130 were used also to compare with fly ash. Coagulant/flocculant type/dosage, mixing time/speed and pH were the experimental parameters. The performances in the experimental studies were assessed with the change in the interface height during sedimentation resultant and turbidity values of treated water. The highest sedimentation efficiency was achieved with anionic flocculant. However, it was determined that fly ash can be used instead of FeCl3 and Al2(SO4)3 in the travertine plant as a coagulant.

Keywords: dewatering, flocculant, fly ash, marble plant wastewater

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2580 Synthesis of a Serie of Metallic Complexes Derived from bis(4-Amino-5-Mercapto-1,2,4-Triazol-3-yl)butane with First Raw Transition Metals

Authors: I. Belbachir, T. Benabdallah, N. Belhadj

Abstract:

The present research work describes the synthesis, through a multi-step strategy, as well as the structural characterization of a polydentate organic ligand, namely the bis(4-amino-5-mercapto-1,2,4-triazole-3-yl)butane (BAMT). The bis-triazolic ligand was characterized by different spectroscopic studies, in order to enlighten its coordination mode, in the neutral and deprotonated forms, towards cobalt(II), nickel(II) and copper(II) sulfates, in both solution and solid state. The stoichiometry of the complexes [neutral BAMT-metal] and [deprotonated BAMT-metal] was first established in a solution of DMF with each of the three metallic cations and their complexation constants calculated, allowing us to compare the stability of the various prepared complexes. The various complexes were finally isolated in the solid state and the coordination mode of neutral and deprotonated BAMT explored towards each of the three metallic sulfates. The establishment of some ligand field parameters (Dq, B, β…) by electronic spectroscopy finally allowed to compare the coordination modes of BAMT towards each of the three metals and to highlight the influence of the deprotonation on the complexing properties of the bis-triazolic ligand.

Keywords: 1, 2, 4-triazol, bis-1, 2, 4-triazol, metallic complexes, coordination in solution and solid state

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2579 Second-Order Slip Flow and Heat Transfer in a Long Isothermal Microchannel

Authors: Huei Chu Weng, Chien-Hung Liu

Abstract:

This paper presents a study on the effect of second-order slip and jump on forced convection through a long isothermally heated or cooled planar microchannel. The fully developed solutions of thermal flow fields are analytically obtained on the basis of the second-order Maxwell-Burnett slip and Smoluchowski jump boundary conditions. Results reveal that the second-order term in the Karniadakis slip boundary condition is found to contribute a negative velocity slip and then to lead to a higher pressure drop as well as a higher fluid temperature for the heated-wall case or to a lower fluid temperature for the cooled-wall case. These findings are contrary to predictions made by the Deissler model. In addition, the role of second-order slip becomes more significant when the Knudsen number increases.

Keywords: microfluidics, forced convection, gas rarefaction, second-order boundary conditions

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2578 Modification and Surface Characterization of the Co20Cr15W10Ni Alloy for Application as Biomaterial

Authors: Fernanda A. Vechietti, Natália O. B. Muniz, Laura C. Treccani, Kurosch. Rezwan, Luis Alberto dos Santos

Abstract:

CoCr alloys are widely used in prosthetic implants due to their excellent mechanical properties, such as good tensile strength, elastic modulus and wear resistance. Their biocompatibility and lack of corrosion are also prominent features of this alloy. One of the most effective and simple ways to protect metal’s surfaces are treatments, such as electrochemical oxidation by passivation, which is used as a protect release of metallic ions. Another useful treatment is the electropolishing, which is used to reduce the carbide concentration and protrusion at the implanted surface. Electropolishing is a cheap and effective method for treatment of implants, which generally has complex geometries. The purpose of this study is surface modification of the alloy CoCr(ASTM F90-09) by different methods: polishing, electro polishing, passivation and heat treatment for application as biomaterials. The modification of the surface was studied and characterized by SEM, profilometry, wettability and compared to the surface of the samples untreated. The heat treatment and of passivation increased roughness (0.477 µm and 0.825 µm) the samples in relation the sample electropolished and polished(0.131 µm and 0.274 µm) and were observed the improve wettability’s with the increase the roughness.

Keywords: biomaterial, CoCr, surface treatment, heat treatment, roughness

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2577 Improved Artificial Bee Colony Algorithm for Non-Convex Economic Power Dispatch Problem

Authors: Badr M. Alshammari, T. Guesmi

Abstract:

This study presents a modified version of the artificial bee colony (ABC) algorithm by including a local search technique for solving the non-convex economic power dispatch problem. The local search step is incorporated at the end of each iteration. Total system losses, valve-point loading effects and prohibited operating zones have been incorporated in the problem formulation. Thus, the problem becomes highly nonlinear and with discontinuous objective function. The proposed technique is validated using an IEEE benchmark system with ten thermal units. Simulation results demonstrate that the proposed optimization algorithm has better convergence characteristics in comparison with the original ABC algorithm.

Keywords: economic power dispatch, artificial bee colony, valve-point loading effects, prohibited operating zones

Procedia PDF Downloads 250
2576 Non-Homogeneity in a Thick Walled Rotating Circular Cylinder under Varying Pressure

Authors: Jatinder Kaur, Pankaj Thakur

Abstract:

The effect of pressure and temperature in non-homogeneous circular cylinder by taking non-homogeneity of material in terms of compressibility c=c₀r⁻ᵏ has been observed. From the results, it could be seen that for K<0, high pressure is required in the initial yielding state than for the case K >0. Under thermal conditions for value K<0, lesser amount of pressure is required for initial yielding, and further, the amount keeps on decreasing with an increase in temperature. Curves are drawn between pressure and radii ratio for initial and fully plastic state with and without temperature conditions. Further graphs between stresses (hoop and radial) and radii ratio for fully plastic state with and without temperature conditions are also drawn and concluded that hoop stresses become minimum with the increase in temperature as compared to radial stresses.

Keywords: cylinder, elastic, plastic, copper, steel, stresses, pressure, load

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2575 Promotion of Renewable Marines Energies in Morocco: Perspectives and Strategies

Authors: Nachtane Mourad, Tarfaoui Mostapha, Saifaoui Dennoun, El Moumen Ahmed

Abstract:

The current energy policy recommends the subject of energy efficiency and to phase out fossil energy as a master question for the prospective years. The kingdom requires restructuring its power equipment by improving the percentage of renewable energy supply and optimizing power systems and storage. Developing energy efficiency, therefore, obliges as a consubstantial objection to reducing energy consumption. The objective of this work is to show the energy transition in Morocco towards renewable energies, in particular, to show the great potential of renewable marine energies in Morocco, This goes back to the advantages of cost and non-pollution in addition to that of the independence of fossil energies. Bearing in mind the necessity of the balance of the Moroccan energy mix, hydraulic and thermal power plants have also been installed which will be added to the power stations already established as a prospect for a balanced network that is flexible to fluctuate demand.

Keywords: renewable marine energy, energy transition, efficiency energy, renewable energy

Procedia PDF Downloads 269
2574 The Nonlinear Optical Properties Analysis of AlPc-Cl Organic Compound

Authors: M. Benhaliliba, A. Ben Ahmed, C.E. Benouis, A.Ayeshamariam

Abstract:

The properties of nonlinear optical NLOs are examined, and the results confirm the 2.19 eV HOMO-LUMO mismatch. In the Al-Pc cluster, certain functional bond lengths and bond angles have been observed. The Quantum chemical method (DFT and TD-DFT) and Vibrational spectra properties of AlPc are studied. X-ray pattern reveals the crystalline structure along with the (242) orientation of the AlPc organic thin layer. UV-Vis shows the frequency selective behavior of the device. The absorbance of such layer exhibits a high value within the UV range and two consecutive peaks within visible range. Spin coating is used to make an organic diode based on the Aluminium-phthalocynanine (AlPc-Cl) molecule. Under dark and light conditions, electrical characterization of Ag/AlPc/Si/Au is obtained. The diode's high rectifying capability (about 1x104) is subsequently discovered. While the height barrier is constant and saturation current is greatly reliant on light, the ideality factor of such a diode increases to 6.9 which confirms the non-ideality of such a device. The Cheung-Cheung technique is employed to further the investigation and gain additional data such as series resistance and barrier height.

Keywords: AlPc-Cl organic material, nonlinear optic, optical filter, diode

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2573 Thermal Stabilisation of Poly(a)•Poly(U) by TMPyP4 and Zn(X)TMPyP4 Derivatives in Aqueous Solutions

Authors: A. Kudrev

Abstract:

The duplex Poly(A)-Poly(U) denaturation in an aqueous solutions in mixtures with the tetracationic MeTMPyP4 (Me = 2H, Zn(II); TMPyP4 is 5,10,15,20-tetrakis(N-methylpyridinium-4-yl)porphyrin), was investigated by monitoring the changes in the UV-Vis absorbance spectrum with increasing temperatures from 20°С to 70°С (рН 7.0, I=0.15M). The absorbance data matrices were analyzed with a versatile chemometric procedure that provides the melting profile (distribution of species) and the pure spectrum for each chemical species present along the heating experiment. As revealed by the increase of Tm, the duplex structure was stabilized by these porphyrins. The values of stabilization temperature ΔTm in the presence of these porphyrins are relatively large, 1.2-8.4 °C, indicating that the porphyrins contribute differently in stabilizing the duplex Poly(A)-Poly(U) structure. Remarkable is the fact that the porphyrin TMPyP4 was less effective in the stabilization of the duplex structure than the metalloporphyrin Zn(X)TMPyP4 which suggests that metallization play an important role in porphyrin-RNA binding. Molecular Dynamics Simulations has been used to illustrate melting of the duplex dsRNA bound with a porphyrin molecule.

Keywords: melting, Poly(A)-Poly(U), TMPyP4, Zn(X)TMPyP4

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2572 Geoelectric Survey for Groundwater Potential in Waziri Umaru Federal Polytechnic, Birnin Kebbi, Nigeria

Authors: Ibrahim Mohammed, Suleiman Taofiq, Muhammad Naziru Yahya

Abstract:

Geoelectrical measurements using Schlumberger Vertical Electrical Sounding (VES) method were carried out in Waziri Umaru Federal Polytechnic, Birnin Kebbi, Nigeria, with the aim of determining the groundwater potential in the area. Twelve (12) Vertical Electric Sounding (VES) data were collected using Terrameter (ABEM SAS 300c) and analyzed using computer software (IPI2win), which gives an automatic interpretation of the apparent resistivity. The results of the interpretation of VES data were used in the characterization of three to five geo-electric layers from which the aquifer units were delineated. Data analysis indicated that water bearing formation exists in the third and fourth layers having resistivity range of 312 to 767 Ωm and 9.51 to 681 Ωm, respectively. The thickness of the formation ranges from 14.7 to 41.8 m, while the depth is from 8.22 to 53.7 m. Based on the result obtained from the interpretation of the data, five (5) VES stations were recommended as the most viable locations for groundwater exploration in the study area. The VES stations include VES A4, A5, A6, B1, and B2. The VES results of the entire area indicated that the water bearing formation occurs at maximum depth of 53.7 m at the time of this survey.

Keywords: aquifer, depth, groundwater, resistivity, Schlumberger

Procedia PDF Downloads 159
2571 Characterization of Self-Assembly Behavior of 1-Dodecylamine Molecules on Au (111) Surface

Authors: Wan-Tzu Yen, Yu-Chen Luo, I-Ping Liu, Po-Hsuan Yeh, Sheng-Hsun Fu, Yuh-Lang Lee

Abstract:

Self-assembled characteristics and adsorption performance of 1-dodecylamine molecules on gold (Au) (111) surfaces were characterized via cyclic voltammetry (CV), surface-enhanced infrared absorption spectroscopy (SEIRAS) and scanning tunneling microscopy (STM). The present study focused on the formation of 1-dodecylamine (DDA) on a gold surface with respect to the ex-situ arrangement of an adlayer on the Au(111) surface, and phase transition at potential dynamics carried out by EC-STM. This study reveals that alkyl amine molecules were formed an adsorption pattern with highly regular “lie down shape” on Au(111) surface, even in an extreme acid system (pH = 1). Acidic electrolyte (HClO₄) could protonate the surface of alkyl amine of a monolayer of the gold surface when potential shifts to negative. The quite stability of 1-dodecylamine on the gold surface maintained the monolayer across the potential window (0.1-0.8V). This transform model was confirmed by EC-STM. In addition, amine-modified Au(111) electrode adlayer used to examine how to affect an electron transfer across an interface using [Fe(CN)₆]³⁻/[Fe(CN)₆]⁴⁻ redox pair containing 0.1 M HClO₄ solution.

Keywords: cyclic voltammetry, dodecylamine, gold (Au)(111), scanning tunneling microscopy, self-assembled monolayer, surface-enhanced infrared absorption spectroscopy

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2570 Detecting HCC Tumor in Three Phasic CT Liver Images with Optimization of Neural Network

Authors: Mahdieh Khalilinezhad, Silvana Dellepiane, Gianni Vernazza

Abstract:

The aim of the present work is to build a model based on tissue characterization that is able to discriminate pathological and non-pathological regions from three-phasic CT images. Based on feature selection in different phases, in this research, we design a neural network system that has optimal neuron number in a hidden layer. Our approach consists of three steps: feature selection, feature reduction, and classification. For each ROI, 6 distinct set of texture features are extracted such as first order histogram parameters, absolute gradient, run-length matrix, co-occurrence matrix, autoregressive model, and wavelet, for a total of 270 texture features. We show that with the injection of liquid and the analysis of more phases the high relevant features in each region changed. Our results show that for detecting HCC tumor phase3 is the best one in most of the features that we apply to the classification algorithm. The percentage of detection between these two classes according to our method, relates to first order histogram parameters with the accuracy of 85% in phase 1, 95% phase 2, and 95% in phase 3.

Keywords: multi-phasic liver images, texture analysis, neural network, hidden layer

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2569 Molecular Dynamics Simulations of the Structural, Elastic and Thermodynamic Properties of Cubic GaBi

Authors: M. Zemouli, K. Amara, M. Elkeurti, Y. Benallou

Abstract:

We present the molecular dynamic simulations results of the structural and dynamical properties of the zinc-blende GaBi over a wide range of temperature (300-1000) K. Our simulation where performed in the framework of the three-body Tersoff potential, which accurately reproduces the lattice constants and elastic constants of the GaBi. A good agreement was found between our calculated results and the available theoretical data of the lattice constant, the bulk modulus and the cohesive energy. Our study allows us to predict the thermodynamic properties such as the specific heat and the lattice thermal expansion. In addition, this method allows us to check its ability to predict the phase transition of this compound. In particular, the transition pressure to the rock-salt phase is calculated and the results are compared with other available works.

Keywords: Gallium compounds, molecular dynamics simulations, interatomic potential thermodynamic properties, structural phase transition

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2568 Characterization of the Queuine Salvage Pathway From Bacteria in the Human Parasite Entamoeba Histolytica

Authors: Lotem Sarid, Meirav Trebicz-Geffen, Serge Ankri

Abstract:

Queuosine (Q) is a naturally occurring modified nucleoside that occurs in the first position of transfer RNA anticodons such as Asp, Asn, His, and Tyr. As eukaryotes lack pathways to synthesize queuine, the nucleobase of queuosine, they must obtain it from their diet or gut microbiota. Our previous work investigated the effects of queuine on the physiology of the eukaryotic parasite Entamoeba histolytica and defined the enzyme EhTGT responsible for its incorporation into tRNA. To our best knowledge, it is unknown how E. histolytica salvages Q from gut bacteria. We used N-acryloyl-3-aminophenylboronic acid (APB) PAGE analysis to demonstrate that E. histolytica trophozoites can salvage queuine from Q or E. coli K12 but not from the modified E. coli QueC strain, which cannot produce queuine. Next, we examined the role of EhDUF2419, a protein with homology to DNA glycosylase, as a queuine salvage enzyme in E. histolytica. When EhDUF2419 expression is silenced, it inhibits Q's conversion to queuine, resulting in a decrease in Q-tRNA levels. We also observed that Q protects control trophozoites from oxidative stress (OS), but not siEhDUF2419 trophozoites. Overall, our data reveal that EhDUF2419 is central for the salvaging of queuine from bacteria and for the resistance of the parasite to OS.

Keywords: entamoeba histolytica, epitranscriptomics, gut microbiota, queuine, queuosine, response to oxidative stress, tRNA modification.

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2567 Mass-Transfer Processes of Textile Dyes Adsorption onto Food Waste Adsorbent

Authors: Amel Asselah, Nadia Chabli, Imane Haddad

Abstract:

The adsorption of methylene blue and congo red dyes in an aqueous solution, on a food waste adsorbent: potato peel, and on a commercial adsorbent: activated carbon powder, was investigated using batch experiments. The objective of this study is the valorization of potato peel by its application in the elimination of these dyes. A comparison of the adsorption efficiency with a commercial adsorbent was carried out. Characterization of the potato peel adsorbent was performed by scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy, Fourier transforms infrared spectroscopy, X-ray diffraction, and X-ray fluorescence. Various parameters were analyzed, in particular: the adsorbent mass, the initial dye concentration, the contact time, the pH, and the temperature. The results reveal that it is about 98% for methylene blue-potato peel, 84% for congo red-potato peel, 84% for methylene blue-activated carbon, and 66% for congo red-activated carbon. The kinetic data were modeled by different equations and revealed that the adsorption of textile dyes on adsorbents follows the model pseudo-second-order, and the particular extra diffusion governs the adsorption mechanism. It has been found that the adsorption process could be described by the Langmuir isotherm.

Keywords: bioadsorbent, waste valorization, adsorptio, textile dyes

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2566 Genomic Diversity of Clostridium perfringens Strains in Food and Human Sources

Authors: Asma Afshari, Abdollah Jamshidi, Jamshid Razmyar, Mehrnaz Rad

Abstract:

Clostridium perfringens is a serious pathogen which causes enteric diseases in domestic animals and food poisoning in humans. Spores can survive cooking processes and play an important role in the possible onset of disease. In this study RAPD-PCR and REP-PCR were used to examine the genetic diversity of 49isolates ofC. Perfringens type A from 3 different sources. The results of RAPD-PCR revealed the most genetic diversity among poultry isolates, while human isolates showed the least genetic diversity. Cluster analysis obtained from RAPD_PCR and based on the genetic distances split the 49 strains into five distinct major clusters (A, B, C, D, and E). Cluster A and C were composed of isolates from poultry meat, cluster B was composed of isolates from human feces, cluster D was composed of isolates from minced meat, poultry meat and human feces and cluster E was composed of isolates from minced meat. Further characterization of these strains by using (GTG) 5 fingerprint repetitive sequence-based PCR analysis did not show further differentiation between various types of strains. To our knowledge, this is the first study in which the genetic diversity of C. perfringens isolates from different types of meats and human feces has been investigated.

Keywords: C. perfringens, genetic diversity, RAPD-PCR, REP-PCR

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2565 Identification and Characterization of 18S rRNA Gene of Demodex Canis From the Dog Population of Mizoram, India

Authors: Moneesh Thakur, Hridayesh Prasad, Nikitasha Bora, Parimal Roy Choudhary, A. K. Samanta, Sanjeev Kumar

Abstract:

Canine demodicosis is a common parasitic condition which involves dog skin. Demodicosis in dogs is due the prominent growth of Demodex. Out of various canine Demodex spp., Demodex canis is the most often involved species. Canine demodicosis can occur as either a localized or generalized form of demodicosis severely affect the dogs and in non-treated dogs may cause death. This study was planned with the aim to screen and characterize the 18S rRNA gene of isolated Demodex canis. A total of 1200 dogs were screened during this study period. The skin scrapings of all the suspected dogs were examined under a microscope at 100X magnification for the presence of Demodex canis. The skin scrapings positive for Demodex canis were examined using PCR for confirmation. A total of 35 dogs were confirmed a positive result for D. canis based on 18S rRNA gene amplification by PCR. Further, the 18S rRNA gene of isolated Demodex canis was cloned and sequenced for genome analysis. On the sequence analysis, it was found that isolated sequence (GenBank Accession No. MK177513) had close similarity (99.7%) to that of D. canis genotype of China (Accession No. MG372254).

Keywords: PCR, phylogenetic analysis, cloning and sequening, Demodex canis

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2564 Synthesis and Characterization of Nickel and Sulphur Sensitized Zinc Oxide Structures

Authors: Ella C. Linganiso, Bonex W. Mwakikunga, Trilock Singh, Sanjay Mathur, Odireleng M. Ntwaeaborwa

Abstract:

The use of nanostructured semiconducting material to catalyze degradation of environmental pollutants still receives much attention to date. One of the desired characteristics for pollutant degradation under ultra-violet visible light is the materials with extended carrier charge separation that allows for electronic transfer between the catalyst and the pollutants. In this work, zinc oxide n-type semiconductor vertically aligned structures were fabricated on silicon (100) substrates using the chemical bath deposition method. The as-synthesized structures were treated with nickel and sulphur. X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy were used to characterize the phase purity, structural dimensions and elemental composition of the obtained structures respectively. Photoluminescence emission measurements showed a decrease in both the near band edge emission as well as the defect band emission upon addition of nickel and sulphur with different concentrations. This was attributed to increased charger-carrier-separation due to the presence of Ni-S material on ZnO surface, which is linked to improved charge transfer during photocatalytic reactions.

Keywords: Carrier-charge-separation, nickel, photoluminescence, sulphur, zinc oxide

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2563 De Novo Assembly and Characterization of the Transcriptome during Seed Development, and Generation of Genic-SSR Markers in Pomegranate (Punica granatum L.)

Authors: Ozhan Simsek, Dicle Donmez, Burhanettin Imrak, Ahsen Isik Ozguven, Yildiz Aka Kacar

Abstract:

Pomegranate (Punica granatum L.) is known to be one of the oldest edible fruit tree species, with a wide geographical global distribution. Fruits from the two defined varieties (Hicaznar and 33N26) were taken at intervals after pollination and fertilization at different sizes. Seed samples were used for transcriptome sequencing. Primary sequencing was produced by Illumina Hi-Seq™ 2000. Firstly, we had raw reads, and it was subjected to quality control (QC). Raw reads were filtered into clean reads and aligned to the reference sequences. De novo analysis was performed to detect genes expressed in seeds of pomegranate varieties. We performed downstream analysis to determine differentially expressed genes. We generated about 27.09 gb bases in total after Illumina Hi-Seq sequencing. All samples were assembled together, we got 59,264 Unigenes, the total length, average length, N50, and GC content of Unigenes are 84.547.276 bp, 1.426 bp, 2,137 bp, and 46.20 %, respectively. Unigenes were annotated with 7 functional databases, finally, 42.681(NR: 72.02%), 39.660 (NT: 66.92%), 30.790 (Swissprot: 51.95%), 20.212 (COG: 34.11%), 27.689 (KEGG: 46.72%), 12.328 (GO: 20.80%), and 33,833 (Interpro: 57.09%) Unigenes were annotated. With functional annotation results, we detected 42.376 CDS, and 4.999 SSR distribute on 16.143 Unigenes.

Keywords: next generation sequencing, SSR, RNA-Seq, Illumina

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2562 Plasma Spray Deposition of Bio-Active Coating on Titanium Alloy (Ti-6Al-4V) Substrate

Authors: Renu Kumari, Jyotsna Dutta Majumdar

Abstract:

In the present study, composite coating consisting of hydroxyapatite (HA) + 50 wt% TiO2 has been developed on Ti-6Al-4V substrate by plasma spray deposition technique. Followed by plasma spray deposition, detailed surface roughness and microstructural characterization were carried out by using optical profilometer and scanning electron microscopy (SEM), respectively. The composition and phase analysis were carried out by energy-dispersive X-ray spectroscopy analysis, and X-ray diffraction (XRD) technique, respectively. The bio-activity behavior of the uncoated and coated samples was also compared by dipping test in Hank’s solution. The average surface roughness of the coating was 10 µm (as compared to 0.5 µm of as-received Ti-6Al-4V substrate) with the presence of porosities. The microstructure of the coating was found to be continuous with the presence of solidified splats. A detailed XRD analysis shows phase transformation of TiO2 from anatase to rutile, decomposition of hydroxyapatite, and formation of CaTiO3 phase. Standard dipping test confirmed a faster kinetics of deposition of calcium phosphate in the coated HA+50% wt.% TiO2 surface as compared to the as-received substrate.

Keywords: titanium, plasma spraying, microstructure, bio-activity, TiO2, hydroxyapatite

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2561 Comparative Analysis of Technologies for Production of Granular NPKS-Fertilizers

Authors: Andrey Norov

Abstract:

Based on a comparison of technologies for the production of granular nitrate-containing and nitrate-free NPKS-fertilizers, this paper considers the effect of process parameters on the economic feasibility of production, on physical & chemical, and structural & mechanical properties and quality of final products (caking, static strength of granules, hygroscopicity, etc.), as well as on thermal stability of fertilizers, eco-friendly production, and other aspects. This comparative analysis allows to select the optimal technology for specific conditions and requirements. Additionally, the report considers flexible, a unique technology for the production of granular NPKS-fertilizers containing sulfur and calcium, suggested by Samoilov Research Institute for Mineral Fertilizers JSC “NIUIF” - the oldest industry-oriented institute in Russia. This technology is implemented at one of the Russian plants where combined drum is used for granulation and drying.

Keywords: caking, granule static strength, granulating-drying drum, NPKS-fertilizers

Procedia PDF Downloads 105