Search results for: Scanning Capacitance Microscope
271 The Strength and Metallography of a Bimetallic Friction Stir Bonded Joint between AA6061 and High Hardness Steel
Authors: Richard E. Miller
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12.7-mm thick plates of 6061-T6511 aluminum alloy and high hardness steel (528 HV) were successfully joined by a friction stir bonding process using a tungsten-rhenium stir tool. Process parameter variation experiments, which included tool design geometry, plunge and traverse rates, tool offset, spindle tilt, and rotation speed, were conducted to develop a parameter set which yielded a defect free joint. Laboratory tensile tests exhibited yield stresses which exceed the strengths of comparable AA6061-to-AA6061 fusion and friction stir weld joints. Scanning electron microscopy and energy dispersive X-ray spectroscopy analysis also show atomic diffusion at the material interface region.
Keywords: Dissimilar materials, friction stir, welding.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2211270 SEM and AFM Investigations of Surface Defects and Tool Wear of Multilayers Coated Carbide Inserts
Authors: Ayman M. Alaskari, Samy E. Oraby, Abdulla I. Almazrouee
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Coated tool inserts can be considered as the backbone of machining processes due to their wear and heat resistance. However, defects of coating can degrade the integrity of these inserts and the number of these defects should be minimized or eliminated if possible. Recently, the advancement of coating processes and analytical tools open a new era for optimizing the coating tools. First, an overview is given regarding coating technology for cutting tool inserts. Testing techniques for coating layers properties, as well as the various coating defects and their assessment are also surveyed. Second, it is introduced an experimental approach to examine the possible coating defects and flaws of worn multicoated carbide inserts using two important techniques namely scanning electron microscopy and atomic force microscopy. Finally, it is recommended a simple procedure for investigating manufacturing defects and flaws of worn inserts.Keywords: AFM, Coated inserts, Defects, SEM.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3047269 CT Reconstruction from a Limited Number of X-Ray Projections
Authors: Tao Quang Bang, Insu Jeon
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Most CT reconstruction system x-ray computed tomography (CT) is a well established visualization technique in medicine and nondestructive testing. However, since CT scanning requires sampling of radiographic projections from different viewing angles, common CT systems with mechanically moving parts are too slow for dynamic imaging, for instance of multiphase flows or live animals. A large number of X-ray projections are needed to reconstruct CT images, so the collection and calculation of the projection data consume too much time and harmful for patient. For the purpose of solving the problem, in this study, we proposed a method for tomographic reconstruction of a sample from a limited number of x-ray projections by using linear interpolation method. In simulation, we presented reconstruction from an experimental x-ray CT scan of a Aluminum phantom that follows to two steps: X-ray projections will be interpolated using linear interpolation method and using it for CT reconstruction based upon Ordered Subsets Expectation Maximization (OSEM) method.Keywords: CT reconstruction, X-ray projections, Interpolation technique, OSEM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2394268 Antifungal Activity of Silver Colloidal Nanoparticles against Phytopathogenic Fungus (Phomopsis sp.) in Soybean Seeds
Authors: J. E. Mendes, L.Abrunhosa, J. A. Teixeira, E. R. de Camargo, C. P. de Souza, J. D. C. Pessoa
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Among the many promising nanomaterials with antifungal properties, metal nanoparticles (silver nanoparticles) stand out due to their high chemical activity. Therefore, the aim of this study was to evaluate the effect of silver nanoparticles (AgNPs) against Phomopsis sp. AgNPs were synthesized by silver nitrate reduction with sodium citrate and stabilized with ammonia. The synthesized AgNPs have further been characterized by UV/Visible spectroscopy, Biophysical techniques like Dynamic light scattering (DLS) and Scanning Electron Microscopy (SEM). The average diameter of the prepared silver colloidal nanoparticles was about 52 nm. Absolute inhibitions (100%) were observed on treated with a 270 and 540 µg ml-1 concentration of AgNPs. The results from the study of the AgNPs antifungal effect are significant and suggest that the synthesized silver nanoparticles may have an advantage compared with conventional fungicides.
Keywords: Antifungal activity, Phomopsis sp., Seeds, Silver Nanoparticles, Soybean.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2122267 Assessing the Antimicrobial Activity of Chitosan Nanoparticles by Fluorescence-Labeling
Authors: Laidson P. Gomes, Cristina T. Andrade, Eduardo M. Del Aguila, Cameron Alexander, Vânia M. F. Paschoalin
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Chitosan is a natural polysaccharide prepared by the N-deacetylation of chitin. In this study, the physicochemical and antibacterial properties of chitosan nanoparticles, produced by ultrasound irradiation, were evaluated. The physicochemical properties of the nanoparticles were determined by dynamic light scattering and zeta potential analysis. Chitosan nanoparticles inhibited the growth of E. coli. The minimum inhibitory concentration (MIC) values were lower than 0.5 mg/mL, and the minimum bactericidal concentration (MBC) values were similar or higher than MIC values. Confocal laser scanning micrographs (CLSM) were used to observe the interaction between E. coli suspensions mixed with FITC-labeled chitosan polymers and nanoparticles.
Keywords: Chitosan nanoparticles, dynamic light scattering, zeta potential, confocal microscopy, antibacterial activity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1076266 On the Oil Repellency of Nanotextured Aluminum Surface
Authors: G. Momen, R. Jafari, M. Farzaneh
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Two different superhydrophobic surfaces were elaborated and their oil repellency behavior was evaluated using several liquid with different surface tension. A silicone rubber/SiO2 nanocomposite coated (A) on aluminum substrate by “spin-coating" and the sample B was an anodized aluminum surface covered by Teflon-like coating. A high static contact angle about ∼162° was measured for two prepared surfaces on which the water droplet rolloff. Scanning electron microscopy (SEM) showed the presence of micro/nanostructures for both sample A and B similar to that of lotus leaf. However the sample A presented significantly different behaviour of wettability against the low surface tension liquid. Sample A has been wetted totally by oil (dodecan) droplet while sample B showed oleophobic behaviour. Oleophobic property of Teflon like coating can be contributed to the presence of CF2 and CF3 functional group which was shown by XPS analysis.Keywords: Oleophobic, Superhydrophobic, Aluminum surface, Nano-texture.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2250265 Removal of Tartrazine Dye form Aqueous Solutions by Adsorption on the Surface of Polyaniline/Iron Oxide Composite
Authors: Salem Ali Jebreil
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In this work, a polyaniline/Iron oxide (PANI/Fe2O3) composite was chemically prepared by oxidative polymerization of aniline in acid medium, in presence of ammonium persulphate as an oxidant and amount of Fe2O3. The composite was characterized by a scanning electron microscopy (SEM). The prepared composite has been used as adsorbent to remove Tartrazine dye form aqueous solutions. The effects of initial dye concentration and temperature on the adsorption capacity of PANI/Fe2O3 for Tartrazine dye have been studied in this paper. The Langmuir and Freundlich adsorption models have been used for the mathematical description of adsorption equilibrium data. The best fit is obtained using the Freundlich isotherm with an R2 value of 0.998. The change of Gibbs energy, enthalpy, and entropy of adsorption has been also evaluated for the adsorption of Tartrazine onto PANI/ Fe2O3. It has been proved according the results that the adsorption process is endothermic in nature.
Keywords: Adsorption, Composite, dye, Polyaniline, Tartrazine.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2471264 Railway Crane Accident: A Comparative Metallographic Test on Pins Fractured during Operation
Authors: Thiago Viana
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Eventually train accidents occur on railways and for some specific cases it is necessary to use a train rescue with a crane positioned under a platform wagon. These tumbled machines are collected and sent to the machine shop or scrap yard. In one of these cranes that were being used to rescue a wagon, occurred a fall of hoist due to fracture of two large pins. The two pins were collected and sent for failure analysis. This work investigates the main cause and the secondary causes for the initiation of the fatigue crack. All standard failure analysis procedures were applied, with careful evaluation of the characteristics of the material, fractured surfaces and, mainly, metallographic tests using an optical microscope to compare the geometry of the peaks and valleys of the thread of the pins and their respective seats. By metallographic analysis, it was concluded that the fatigue cracks were started from a notch (stress concentration) in the valley of the threads of the pin applied to the right side of the crane (pin 1). In this, it was verified that the peaks of the threads of the pin seat did not have proper geometry, with sharp edges being present that caused such notches. The visual analysis showed that fracture of the pin on the left side of the crane (pin 2) was brittle type, being a consequence of the fracture of the first one. Recommendations for this and other railway cranes have been made, such as nondestructive testing, stress calculation, design review, quality control and suitability of the mechanical forming process of the seat threads and pin threads.
Keywords: Crane, fracture, pin, railway.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 513263 An Improved Fast Search Method Using Histogram Features for DNA Sequence Database
Authors: Qiu Chen, Feifei Lee, Koji Kotani, Tadahiro Ohmi
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In this paper, we propose an efficient hierarchical DNA sequence search method to improve the search speed while the accuracy is being kept constant. For a given query DNA sequence, firstly, a fast local search method using histogram features is used as a filtering mechanism before scanning the sequences in the database. An overlapping processing is newly added to improve the robustness of the algorithm. A large number of DNA sequences with low similarity will be excluded for latter searching. The Smith-Waterman algorithm is then applied to each remainder sequences. Experimental results using GenBank sequence data show the proposed method combining histogram information and Smith-Waterman algorithm is more efficient for DNA sequence search.Keywords: Fast search, DNA sequence, Histogram feature, Smith-Waterman algorithm, Local search
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1329262 Influence of Hydrolytic Degradation on Properties of Moisture Membranes Used in Fire-Protective Clothing
Authors: Rachid El Aidani, Phuong Nguyen-Tri, Toan Vu-Khanh
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This study intends to show the influence of the hydrolytic degradation on the properties of the e-PTFE/NOMEX® membranes used in fire-protective clothing. The modification of water vapour permeability, morphology and chemical structure was examined by MOCON Permatran, electron microscopy scanning (SEM), and ATR-FTIR, respectively. A decrease in permeability to water vapour of the aged samples was observed following closure of transpiration pores. Analysis of fiber morphology indicates the appearance of defects at the fibers surface with the presence of micro cavities. ATR-FTIR analysis reveals the presence of a new absorption band attributed to carboxylic acid terminal groups generated during the amide bond hydrolysis.Keywords: Hydrolytic ageing, moisture membrane; water vapor permeability, morphology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2365261 Characterization of ZrO2/PEG Composite Film as Immobilization Matrix for Glucose Oxidase
Authors: N. M. Ahmad, J. Abdullah, N. I. Ramli, S. Abd Rahman, N. E. Azmi, Z. Hamzah, A. Saat, N. H. Rahman
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A biosensor based on glucose oxidase (GOx) immobilized onto nanoparticles zirconium oxide with polyethylene nanocomposite for glucose monitoring has been designed. The CTAB/PEG/ZrO2/GOx nanocomposite was deposited onto screen printed carbon paste (SPCE) electrode via spin coating technique. The properties of CTAB/PEG/ZrO2/GOx were study using scanning electron microscopy (SEM). The SPE modified with the CTAB/PEG/ZrO2/GOx showed electrocatalytical response to the oxidation of glucose when ferrocene carboxaldehyde was used as an artificial redox mediator, which was studied by cyclic voltammetry (CV). Several parameters such as working potential, effect of pH and effect of ZrO2/PEG layers that governed the analytical performance of the biosensor, have been studied. The biosensor was applied to detect glucose with a linear range of 0.4 to 2.0 mmol L−1 with good repetability and reproducibility.Keywords: Nanocomposite, Nanoparticles, Modified SPE, Ferrocenecarboxaldehyde.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2262260 The Automated Selective Acquisition System
Authors: Atisthan Wuttimanop, Suchada Rianmora
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To support design process for launching the product on time, reverse engineering (RE) process has been introduced for quickly generating 3D CAD model from its physical object. The accuracy of the 3D CAD model depends upon the data acquisition technique selected, contact or non-contact methods. In order to reduce times used for acquiring surface and eliminating noises, the automated selective acquisition system has been developed and presented in this research as the alternative channel for non-contact acquisition technique where the data is selectively and locally scanned contour by contour without performing data reduction process. The results present as the organized contour points which are directly used to generate 3D virtual model. The comparison between the proposed technique and another non-contact scanning technique has been presented and discussed.
Keywords: Automated selective acquisition system, Non-contact acquisition, Reverse engineering, 3D scanners.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1609259 Sintering Properties of Mechanically Alloyed Ti-5Al-2.5Fe
Authors: Ridvan Yamanoglu, Erdinc Efendi, Ismail Daoud
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In this study, Ti-5Al-2.5Fe alloy was prepared by powder metallurgy. The elemental titanium, aluminum, and iron powders were mechanically alloyed for 10 h in a vacuum atmosphere. A stainless steel jar and stainless steel balls were used for mechanical alloying. The alloyed powders were then sintered by vacuum hot pressing at 950 °C for a soaking time of 30 minutes. Pure titanium was also sintered at the same conditions for comparison of mechanical properties and microstructural behavior. The samples were investigated by scanning electron microscopy, XRD analysis, and optical microscopy. Results showed that, after mechanical alloying, a homogeneous distribution of the elements was obtained, and desired a-b structure was determined. Ti-5Al-2.5Fe alloy was successfully produced, and the alloy showed enhanced mechanical properties compared to the commercial pure titanium.Keywords: Ti5Al2.5Fe, mechanical alloying, hot pressing, sintering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1270258 Thermomechanical and Metallurgical Analysis of SMA and GTA Welded Low Carbon Steel Butt Joints
Authors: J. Dutta, P. Pranith Kumar Reddy
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This research paper portrays a comparative analysis of thermomechanical behaviour of Shielded Metal Arc Welding (SMAW) and Gas Tungsten Arc Welding (GTAW) of low carbon steel of AISI 1020 grade butt joints. The thermal history has been obtained by experimental work. We have focused on temperature dependent cooling rate as depicted by Adam’s two-dimensional model. The effect of moving point heat source of SMAW and GTAW on mechanical properties has been judged by optical and scanning electron micrographs of different regions in weld joints. The microhardness study has been carried to visualize the joint strength due to formation of different phases.
Keywords: Shielded metal arc welding, gas tungsten arc welding, low carbon steel, microhardness study, thermal history, microscopic morphology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2203257 Novel Glycopolymers Containing Carbohydrate Moiety: Copolymerization and Thermal Properties
Authors: Liliana M. Ştefan, Ana M. Pană, Geza Bandur, Marcel Popa, Lucian M. Rusnac
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Polymers are one of the most widely used materials in our every day life. The subject of renewable resources has attracted great attention in the last period of time. New polymeric materials derived from renewable resources, like carbohydrates draw attention to public eye especially because of their biocompatibility and biodegradability. The aim of our paper was to obtain environmentally compatible polymers from monosaccharides. Novel glycopolymers based on D-glucose have been obtained from copolymerization of a new monomer carrying carbohydrate moiety with methyl methacrylate (MMA) via free radical bulk polymerization. Differential scanning calorimetry (DSC) was performed in order to study the copolymerization process of the monomer into the chosen co-monomer; the activation energy of this process was evaluated using Ozawa method. The copolymers obtained were characterized using ATR-FTIR spectroscopy. The thermal stability of the obtained products was studied by thermogravimetry (TG).
Keywords: DSC, glycopolymer, monosaccarides, TG.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1705256 Structural and Optical Characterization of Silica@PbS Core–Shell Nanoparticles
Authors: A. Pourahmad, Sh. Gharipour
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The present work describes the preparation and characterization of nanosized SiO2@PbS core-shell particles by using a simple wet chemical route. This method utilizes silica spheres formation followed by successive ionic layer adsorption and reaction method assisted lead sulphide shell layer formation. The final product was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–vis spectroscopic, infrared spectroscopy (IR) and transmission electron microscopy (TEM) experiments. The morphological studies revealed the uniformity in size distribution with core size of 250 nm and shell thickness of 18 nm. The electron microscopic images also indicate the irregular morphology of lead sulphide shell layer. The structural studies indicate the face-centered cubic system of PbS shell with no other trace for impurities in the crystal structure.Keywords: Core-shell, nanostructure, semiconductor, optical property, XRD.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1202255 Uniform Heating during Focused Ultrasound Thermal Therapy
Authors: To-Yuan Chen, Tzu-Ching Shih, Hao-Li Liu, Kuen-Cheng Ju
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The focal spot of a high intensity focused ultrasound transducer is small. To heat a large target volume, multiple treatment spots are required. If the power of each treatment spot is fixed, it could results in insufficient heating of initial spots and over-heating of later ones, which is caused by the thermal diffusion. Hence, to produce a uniform heated volume, the delivered energy of each treatment spot should be properly adjusted. In this study, we proposed an iterative, extrapolation technique to adjust the required ultrasound energy of each treatment spot. Three different scanning pathways were used to evaluate the performance of this technique. Results indicate that by using the proposed technique, uniform heating volume could be obtained.Keywords: focused ultrasound, thermal therapy, uniform heating, iteration, extrapolation, scan
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1626254 Artificial Intelligence: A Comprehensive and Systematic Literature Review of Applications and Comparative Technologies
Authors: Z. M. Najmi
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Over the years, the question around Artificial Intelligence has always been one with many answers. Whether by means of use in business and industry or complicated algorithmic programming, management of these technologies has always been the core focus. More recently, technologies have been questioned in industry and society alike as to whether they have improved human-centred design, assisted choices and objectives, and had a hand in systematic processes across the board. With these questions the answer may lie within AI technologies, and the steps needed in removing common human error. Elements such as Machine Learning, Deep Learning, Recommender Systems and Natural Language Processing will all be features to consider moving forward. Our previous intervention with AI applications has resulted in increased productivity, however, raised concerns for the continuation of traditional human-centred occupations. Emerging technologies such as Augmented Reality and Virtual Reality have all played a part in this during AI’s prominent rise. As mentioned, AI has been constantly under the microscope; the benefits and drawbacks may seem endless is wide, but AI is something we must take notice of and adapt into our everyday lives. The aim of this paper is to give an overview of the technologies surrounding A.I. and its’ related technologies. A comprehensive review has been written as a timeline of the developing events and key points in the history of Artificial Intelligence. This research is gathered entirely from secondary research, academic statements of knowledge and gathered to produce an understanding of the timeline of AI.
Keywords: Artificial Intelligence, Deep Learning, Augmented Reality, Reinforcement Learning, Machine Learning, Supervised Learning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 576253 Enhancement and Characterization of Titanium Surfaces with Sandblasting and Acid Etching for Dental Implants
Authors: Busra Balli, Tuncay Dikici, Mustafa Toparli
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Titanium and its alloys have been used extensively over the past 25 years as biomedical materials in orthopedic and dental applications because of their good mechanical properties, corrosion resistance, and biocompatibility. It is known that the surface properties of titanium implants can enhance the cellular response and play an important role in Osseo integration. The rate and quality of Osseo integration in titanium implants are related to their surface properties. The purpose of this investigation was to evaluate the effect of sandblasting and acid etching on surface morphology, roughness, the wettability of titanium. The surface properties will be characterized by scanning electron microscopy and contact angle and roughness measurements. The results show that surface morphology, roughness, and wettability were changed and enhanced by these treatments.Keywords: Dental implant, etching, surface modifications, surface morphology, surface roughness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1325252 Retraction Free Motion Approach and Its Application in Automated Robotic Edge Finishing and Inspection Processes
Authors: M. Nemer, E. I. Konukseven
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In this paper, a motion generation algorithm for a six Degrees of Freedom (DoF) robotic hand in a static environment is presented. The purpose of developing this method is to be used in the path generation of the end-effector for edge finishing and inspection processes by utilizing the CAD model of the considered workpiece. Nonetheless, the proposed algorithm may be extended to be applicable for other similar manufacturing processes. A software package programmed in the application programming interface (API) of SolidWorks generates tool path data for the robot. The proposed method significantly simplifies the given problem, resulting in a reduction in the CPU time needed to generate the path, and offers an efficient overall solution. The ABB IRB2000 robot is chosen for executing the generated tool path.Keywords: Offline programming, CAD-based tools, edge deburring, edge scanning, path generation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 912251 Microstructural and Magnetic Properties of Ni50Mn39Sn11 and Ni50Mn36Sn14 Heusler Alloys
Authors: M. Nazmunnahar, J. J. Del Val, A. Vimmrova, J. González
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We report the microstructural and magnetic properties of Ni50Mn39Sn11 and Ni50Mn36Sn14 ribbon Heusler alloys. Experimental results were obtained by differential scanning calorymetry, X-ray diffraction and vibrating sample magnetometry techniques. The Ni-Mn-Sn system undergoes a martensitic structural transformation in a wide temperature range. For example, for Ni50Mn39Sn11 the start and finish temperatures of the martensitic and austenite phase transformation for ribbon alloy were Ms=336K, Mf=328K, As=335K and Af=343K whereas no structural transformation is observed for Ni50Mn36Sn14 alloys. Magnetic measurements show the typical ferromagnetic behavior with Curie temperature 207 K at low applied field of 50 Oe. The complex behavior exhibited by these Heusler alloys should be ascribed to the strong coupling between magnetism and structure, being their magnetic behavior determined by the distance between Mn atoms.Keywords: Structural transformation, as-cast ribbon, Heusler alloys, Magnetic properties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2605250 Design of the Production Line Based On RFID through 3D Modeling
Authors: Aliakbar Akbari, Majid Hashemipour, Shiva Mirshahi
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Radio-frequency identification has entered as a beneficial means with conforming GS1 standards to provide the best solutions in the manufacturing area. It competes with other automated identification technologies e.g. barcodes and smart cards with regard to high speed scanning, reliability and accuracy as well. The purpose of this study is to improve production line-s performance by implementing RFID system in the manufacturing area on the basis of radio-frequency identification (RFID) system by 3D modeling in the program Cinema 4D R13 which provides obvious graphical scenes for users to portray their applications. Finally, with regard to improving system performance, it shows how RFID appears as a well-suited technology in a comparison of the barcode scanner to handle different kinds of raw materials in the production line base on logical process.
Keywords: Radio Frequency Identification, Manufacturing and Production Lines, 3D modeling
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2110249 Apoptotic Induction Ability of Harmalol and Its Binding: Biochemical and Biophysical Perspectives
Authors: Kakali Bhadra
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Harmalol administration caused remarkable reduction in proliferation of HepG2 cells with GI50 of 14.2 mM, without showing much cytotoxicity in embryonic liver cell line, WRL-68. Data from circular dichroism and differential scanning calorimetric analysis of harmalol-CT DNA complex shows conformational changes with prominent CD perturbation and stabilization of CT DNA by 8 oC. Binding constant and stoichiometry was also calculated using the above biophysical techniques. Further, dose dependent apoptotic induction ability of harmalol was studied in HepG2 cells using different biochemical assays. Generation of ROS, DNA damage, changes in cellular external and ultramorphology, alteration of membrane, formation of comet tail, decreased mitochondrial membrane potential and a significant increase in Sub Go/G1 population made the cancer cell, HepG2, prone to apoptosis. Up regulation of p53 and caspase 3 further indicated the apoptotic role of harmalol.
Keywords: Apoptosis, beta carboline alkaloid, comet assay, cytotoxicity, ROS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1192248 Preparation and Characterization of Polyaniline (PANI)-Platinum Nanocomposite
Authors: Kumar Neeraj, Ranjan Haldar
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Polyaniline is an indispensible component in lightemitting devices (LEDs), televisions, cellular telephones, automotive, corrosion-resistant coatings, actuators etc. The electrical conductivity properties was found be increased by introduction of metal nano particles. In the present study, an attempt has been made to utilize platinum nano particles to achieve the improved electrical properties. Polyaniline and Pt-polyaniline composite are synthesized by electrochemical routes. X-ray diffractometer confirms the amorphous nature of polyaniline. The Bragg’s diffraction peaks correspond to platinum nanoparticles in Pt-polyaniline composite and thermogravimetric analyzer indicates its decomposition at certain temperature. The Scanning Electron Micrographs of colloidal platinum nanoparticles were spherical, uniform shape in the composite. The current-voltage (I-V) characteristics of the PANI and composites were also studied which indicate a significant decreasing resistivity than PANI-Platinum after introduction of pt nanoparticles in the matrix of polyaniline (PANI).Keywords: Polyaniline, XRD and Platinum Nanoparticles.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2410247 Increased Solubility, Dissolution and Physicochemical Studies of Curcumin- Polyvinylpyrrolidone K-30 Solid Dispersions
Authors: Nattha Kaewnopparat, Sanae Kaewnopparat, Amaravadee Jangwang, Daungkhae Maneenaun, Thitima Chuchome, Pharkphoom Panichayupakaranant
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Solid dispersions (SD) of curcuminpolyvinylpyrrolidone in the ratio of 1:2, 1:4, 1:5, 1:6, and 1:8 were prepared in an attempt to increase the solubility and dissolution. Solubility, dissolution, powder X-ray diffraction (XRD), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) of solid dispersions, physical mixtures (PM) and curcumin were evaluated. Both solubility and dissolution of curcumin solid dispersions were significantly greater than those observed for physical mixtures and intact curcumin. The powder X-ray diffractograms indicated that the amorphous curcumin was obtained from all solid dispersions. It was found that the optimum weight ratio for curcumin:PVP K-30 is 1:6. The 1:6 solid dispersion still in the amorphous from after storage at ambient temperature for 2 years and the dissolution profile did not significantly different from freshly prepared.Keywords: Curcumin, polyvinylpyrrolidone K-30, solid dispersion, dissolution, physicochemical.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4247246 Effect of Zinc Oxide on Characteristics of Active Flux TIG Welds of 1050 Aluminum Plates
Authors: H. Fazlinejad, A. Halvaee
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In this study, characteristics of ATIG welds using ZnO flux on aluminum was investigated and compared with TIG welds. Autogenously AC-ATIG bead on plate welding was applied on Al1050 plate with a coating of ZnO as the flux. Different levels of welding current and flux layer thickness was considered to study the effect of heat input and flux quantity on ATIG welds and was compared with those of TIG welds. Geometrical investigation of the weld cross sections revealed that penetration depth of the ATIG welds with ZnO flux, was increased up to 2 times in some samples compared to the TIG welds. Optical metallographic and Scanning Electron Microscopy (SEM) observations revealed similar microstructures in TIG and ATIG welds. Composition of the ATIG welds slag was also analyzed using X-ray diffraction. In both TIG and ATIG samples, the lowest values of microhardness were observed in the HAZ.
Keywords: ATIG, active flux, weld penetration, Al 1050, ZnO.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 829245 Performance of Membrane Bioreactor (MBR) in High Phosphate Wastewater
Authors: Aida Isma M. I., Putri Razreena A. R., Rozita Omar, Azni Idris
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This study presents the performance of membrane bioreactor in treating high phosphate wastewater. The laboratory scale MBR was operated at permeate flux of 25 L/m2.h with a hollow fiber membrane (polypropylene, approx. pore size 0.01 - 0.2 μm) at hydraulic retention time (HRT) of 12 hrs. Scanning electron microscopy (SEM) and energy diffusive X-ray (EDX) analyzer were used to characterize the membrane foulants. Results showed that the removal efficiencies of COD, TSS, NH3-N and PO4 3- were 93, 98, 80 and 30% respectively. On average 91% of influent soluble microbial products (SMP) were eliminated, with the eliminations of polysaccharides mostly above 80%. The main fouling resistance was cake resistance. It should be noted that SMP were found in major portions of mixed liquor that played a relatively significant role in membrane fouling. SEM and EDX analyses indicated that the foulants covering the membrane surfaces comprises not only organic substances but also inorganic elements including Mg, Ca, Al, K and P.Keywords: Membrane bioreactor (MBR), membrane fouling, phosphates, soluble microbial products (SMP).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3370244 Preparation of Homogeneous Dense Composite of Zirconia and Alumina (ZTA)using Colloidal Filtration
Authors: H. Wakily, M. Mehrali, H. S. C. Metselaar
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Homogeneous composites of alumina and zirconia with a small amount of MgO (<1 wt %) were prepared by colloidal filtration. The object of using ZrO2 (15wt %) was to provide zirconia toughened alumina (ZTA). Suspensions of alumina and Zirconia with various solid loadings and various concentrations of Dolapix CE64 as surfactant were studied. The stability of these suspensions was investigated using rheological measurements. The optimum amount of using Dolapix was 0.8wt% for ZTA containing MgO suspension which gave low apparent viscosity in basic area (100 mPa s at shear rate of 50 s-1). The satisfactory mixtures were made into sample pallets using colloidal filtration. The process was completed with pressureless sintering in suitable temperature. Phase, grain size and qualitative compositional analysis were done using X-ray diffraction (XRD) and scanning electron microscopy (SEM) images. ZTA containing 0.05 wt% MgO shows the lowest grain size for alumina around 0.5 μm. Densification studies show that near full densities (>99%) were obtained for ZTA ceramic containing 0.05 wt% MgO in 1500 °C.Keywords: Colloidal filtration, Dolapix, MgO, Zirconiatoughened alumina.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2992243 Iron Doped Biomaterial Calcium Borate: Synthesis and Characterization
Authors: G. Çelik Gül, F. Kurtuluş
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Colemanite is the most common borate mineral, and the main source of the boron required by plants, human, and earth. Transition metals exhibit optical and physical properties such as; non-linear optical character, structural diversity, thermal stability, long cycle life and luminescent radiation. The doping of colemanite with a transition metal, bring it very interesting and attractive properties which make them applicable in industry. Iron doped calcium borate was synthesized by conventional solid state method at 1200 °C for 12 h with a systematic pathway. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy/energy dispersive analyze (SEM/EDS) were used to characterize structural and morphological properties. Also, thermal properties were recorded by thermogravimetric-differential thermal analysis (TG/DTA).
Keywords: Colemanite, conventional synthesis, powder x-ray diffraction, borates.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1008242 Application of Ti/RuO2-SnO2-Sb2O5 Anode for Degradation of Reactive Black-5 Dye
Authors: Jayesh P. Ruparelia, Bhavna D. Soni
Abstract:
Electrochemical-oxidation of Reactive Black-5 (RB- 5) was conducted for degradation using DSA type Ti/RuO2-SnO2- Sb2O5 electrode. In the study, for electro-oxidation, electrode was indigenously fabricated in laboratory using titanium as substrate. This substrate was coated using different metal oxides RuO2, Sb2O5 and SnO2 by thermal decomposition method. Laboratory scale batch reactor was used for degradation and decolorization studies at pH 2, 7 and 11. Current density (50mA/cm2) and distance between electrodes (8mm) were kept constant for all experiments. Under identical conditions, removal of color, COD and TOC at initial pH 2 was 99.40%, 55% and 37% respectively for initial concentration of 100 mg/L RB-5. Surface morphology and composition of the fabricated electrode coatings were characterized using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) respectively. Coating microstructure was analyzed by X-ray diffraction (XRD). Results of this study further revealed that almost 90% of oxidation occurred within 5-10 minutes.
Keywords: Electrochemical-oxidation, RB- dye, Decolorization.
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