Search results for: hygrothermal properties
4768 The Effect of Nanofiber Web on Thermal Conductivity, Air and Water Vapor Permeability
Authors: Ilkay Ozsev Yuksek, Nuray Ucar, Zeynep Esma Soygur, Yasemin Kucuk
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In this study, composite fabrics with polyacrylonitrile electrospun nanofiber deposited onto quilted polyester fabric have been produced in order to control the isolation properties such as water vapor permeability, air permeability and thermal conductivity. Different nanofiber webs were manufactured by changing polymer concentration from 10% to 16% and by changing the deposition time from 1 to 3 hours. Presence of nanofiber layer on the quilted fabric results to an increase of an isolation, i.e., a decrease of the moisture vapor transport rates at 20%, decrease of thermal conductivity at 15% and a decrease of air permeability values at 50%.Keywords: nanofiber/fabric composites, electrospinning, isolation, thermal conductivity, moisture vapor transport, air permeability
Procedia PDF Downloads 3044767 Theoretical Study of the Structural and Elastic Properties of Semiconducting Rare Earth Chalcogenide Sm1-XEuXS under Pressure
Authors: R. Dubey, M. Sarwan, S. Singh
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We have investigated the phase transition pressure and associated volume collapse in Sm1– X EuX S alloy (0≤x≤1) which shows transition from discontinuous to continuous as x is reduced. The calculated results from present approach are in good agreement with experimental data available for the end point members (x=0 and x=1). The results for the alloy counter parts are also in fair agreement with experimental data generated from the vegard’s law. An improved interaction potential model has been developed which includes coulomb, three body interaction, polarizability effect and overlap repulsive interaction operative up to second neighbor ions. It is found that the inclusion of polarizability effect has improved our results.Keywords: elastic constants, high pressure, phase transition, rare earth compound
Procedia PDF Downloads 4124766 Analysis of Magnesium Alloy Wheel Forming Technologies for Light Vehicles
Authors: Anna Dziubinska
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The applications of magnesium alloys in transport include all kinds of vehicle wheels for cars, motorcycles, bicycles, trolleys, etc. Modern technologies of manufacturing products from these materials have been noticeably improved recently, creating new possibilities for their application. Continuously developed technologies for forming Mg alloys must not be overlooked, which make it possible to manufacture products with better properties compared to those obtained by casting only. The article reviews the specialized literature on magnesium wheel forming and presents a concept of technology for forging magnesium wheels for light vehicles from cast preforms. The research leading to these results has received funding from the Norway Grants 2014-2021 via the National Centre for Research and Development.Keywords: forming, forging, magnesium alloy, wheels, vehicles
Procedia PDF Downloads 1314765 Synthesis and Use of Bio Polyols in Rigid Polyurethane Foam Production
Authors: A. Esra Pişkin, L. Yusuf Yivlik
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Polyurethane consumption in the world increases every year. Polyetherpolyol, which is the main raw material of polyurethane, is produced from petroleum, and bioresources are needed in polyol production due to the damage it causes to the environment and the consumption of too much energy during the production phase. In this present work, bio polyol was synthesized with castor oil and soybean oil, and its use in rigid polyurethane systems was investigated. Transesterification and ring opening methods were applied for polyol synthesis, and the obtained bio polyols were compared with polyols derived petroleum. The goal of the present study was to synthesize biopolyols and to investigate the mechanical, thermal, and chemical properties of the synthesized polyurethane in terms of bio polyols.Keywords: polyurethane, polyol, biopolyol, vegetable oil, foam, rigid polyurethane foam, ring opening, transesterification
Procedia PDF Downloads 4514764 Development of Perovskite Quantum Dots Light Emitting Diode by Dual-Source Evaporation
Authors: Antoine Dumont, Weiji Hong, Zheng-Hong Lu
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Light emitting diodes (LEDs) are steadily becoming the new standard for luminescent display devices because of their energy efficiency and relatively low cost, and the purity of the light they emit. Our research focuses on the optical properties of the lead halide perovskite CsPbBr₃ and its family that is showing steadily improving performances in LEDs and solar cells. The objective of this work is to investigate CsPbBr₃ as an emitting layer made by physical vapor deposition instead of the usual solution-processed perovskites, for use in LEDs. The deposition in vacuum eliminates any risk of contaminants as well as the necessity for the use of chemical ligands in the synthesis of quantum dots. Initial results show the versatility of the dual-source evaporation method, which allowed us to create different phases in bulk form by altering the mole ratio or deposition rate of CsBr and PbBr₂. The distinct phases Cs₄PbBr₆, CsPbBr₃ and CsPb₂Br₅ – confirmed through XPS (x-ray photoelectron spectroscopy) and X-ray diffraction analysis – have different optical properties and morphologies that can be used for specific applications in optoelectronics. We are particularly focused on the blue shift expected from quantum dots (QDs) and the stability of the perovskite in this form. We already obtained proof of the formation of QDs through our dual source evaporation method with electron microscope imaging and photoluminescence testing, which we understand is a first in the community. We also incorporated the QDs in an LED structure to test the electroluminescence and the effect on performance and have already observed a significant wavelength shift. The goal is to reach 480nm after shifting from the original 528nm bulk emission. The hole transport layer (HTL) material onto which the CsPbBr₃ is evaporated is a critical part of this study as the surface energy interaction dictates the behaviour of the QD growth. A thorough study to determine the optimal HTL is in progress. A strong blue shift for a typically green emitting material like CsPbBr₃ would eliminate the necessity of using blue emitting Cl-based perovskite compounds and could prove to be more stable in a QD structure. The final aim is to make a perovskite QD LED with strong blue luminescence, fabricated through a dual-source evaporation technique that could be scalable to industry level, making this device a viable and cost-effective alternative to current commercial LEDs.Keywords: material physics, perovskite, light emitting diode, quantum dots, high vacuum deposition, thin film processing
Procedia PDF Downloads 1564763 The Influence of Winding Angle on Functional Failure of FRP Pipes
Authors: Roham Rafiee, Hadi Hesamsadat
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In this study, a parametric finite element modeling is developed to analyze failure modes of FRP pipes subjected to internal pressure. First-ply failure pressure and functional failure pressure was determined by a progressive damage modeling and then it is validated using experimental observations. The influence of both winding angle and fiber volume fraction is studied on the functional failure of FRP pipes and it corresponding pressure. It is observed that despite the fact that increasing fiber volume fraction will enhance the mechanical properties, it will be resulted in lower values for functional failure pressure. This shortcoming can be compensated by modifying the winding angle in angle plies of pipe wall structure.Keywords: composite pipe, functional failure, progressive modeling, winding angle
Procedia PDF Downloads 5354762 X-Ray Analysis and Grain Size of CuInx Ga1-X Se2 Solar Cells
Authors: A. I. Al-Bassam, A. M. El-Nggar
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Polycrystalline Cu In I-x GaxSe2 thin films have been fabricated. Some physical properties such as lattice parameters, crystal structure and microstructure of Cu In I-x GaxSe2 were determined using X-ray diffractometry and scanning electron microscopy. X-ray diffraction analysis showed that the films with x ≥ 0.5 have a chalcopyrite structure and the films with x ≤ 0.5 have a zinc blende structure. The lattice parameters were found to vary linearly with composition over a wide range from x = 0 to x =1.0. The variation of lattice parameters with composition was found to obey Vegard's law. The variation of the c/a with composition was also linear. The quality of a wide range of Cu In I-xGaxSe2 thin film absorbers from CuInSe to CuGaSe was evaluated by Photoluminescence (PL) measurements.Keywords: grain size, polycrystalline, solar cells, lattice parameters
Procedia PDF Downloads 5004761 Study of Transport in Electronic Devices with Stochastic Monte Carlo Method: Modeling and Simulation along with Submicron Gate (Lg=0.5um)
Authors: N. Massoum, B. Bouazza
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In this paper, we have developed a numerical simulation model to describe the electrical properties of GaInP MESFET with submicron gate (Lg = 0.5 µm). This model takes into account the three-dimensional (3D) distribution of the load in the short channel and the law effect of mobility as a function of electric field. Simulation software based on a stochastic method such as Monte Carlo has been established. The results are discussed and compared with those of the experiment. The result suggests experimentally that, in a very small gate length in our devices (smaller than 40 nm), short-channel tunneling explains the degradation of transistor performance, which was previously enhanced by velocity overshoot.Keywords: Monte Carlo simulation, transient electron transport, MESFET device, simulation software
Procedia PDF Downloads 5044760 Physical, Textural and Sensory Properties of Noodles Supplemented with Tilapia Bone Flour (Tilapia nilotica)
Authors: Supatchalee Sirichokworrakit
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Fishbone of Nile tilapia (Tilapia nilotica), waste from the frozen Nile tilapia fillet factory, is one of calcium sources. In order to increase fish bone powder value, this study aimed to investigate the effect of tilapia bone flour (TBF) addition (5, 10, 15% by flour weight) on cooking quality, texture and sensory attributes of noodles. The results indicated that tensile strength, color value (a*) and water absorption of noodles significantly decreased (p≤0.05) as the levels of TBF increased from 0-15%. While cooking loss, cooking time and color values (L* and b*) of noodles significantly increased (p≤0.05). Sensory evaluation indicated that noodles with 5% TBF received the highest overall acceptability score.Keywords: tilapia bone flour, noodles, cooking quality, calcium
Procedia PDF Downloads 3964759 A Quantitative Study of the Evolution of Open Source Software Communities
Authors: M. R. Martinez-Torres, S. L. Toral, M. Olmedilla
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Typically, virtual communities exhibit the well-known phenomenon of participation inequality, which means that only a small percentage of users is responsible of the majority of contributions. However, the sustainability of the community requires that the group of active users must be continuously nurtured with new users that gain expertise through a participation process. This paper analyzes the time evolution of Open Source Software (OSS) communities, considering users that join/abandon the community over time and several topological properties of the network when modeled as a social network. More specifically, the paper analyzes the role of those users rejoining the community and their influence in the global characteristics of the network.Keywords: open source communities, social network Analysis, time series, virtual communities
Procedia PDF Downloads 5174758 Polymeric Composites with Synergetic Carbon and Layered Metallic Compounds for Supercapacitor Application
Authors: Anukul K. Thakur, Ram Bilash Choudhary, Mandira Majumder
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In this technologically driven world, it is requisite to develop better, faster and smaller electronic devices for various applications to keep pace with fast developing modern life. In addition, it is also required to develop sustainable and clean sources of energy in this era where the environment is being threatened by pollution and its severe consequences. Supercapacitor has gained tremendous attention in the recent years because of its various attractive properties such as it is essentially maintenance-free, high specific power, high power density, excellent pulse charge/discharge characteristics, exhibiting a long cycle-life, require a very simple charging circuit and safe operation. Binary and ternary composites of conducting polymers with carbon and other layered transition metal dichalcogenides have shown tremendous progress in the last few decades. Compared with bulk conducting polymer, these days conducting polymers have gained more attention because of their high electrical conductivity, large surface area, short length for the ion transport and superior electrochemical activity. These properties make them very suitable for several energy storage applications. On the other hand, carbon materials have also been studied intensively, owing to its rich specific surface area, very light weight, excellent chemical-mechanical property and a wide range of the operating temperature. These have been extensively employed in the fabrication of carbon-based energy storage devices and also as an electrode material in supercapacitors. Incorporation of carbon materials into the polymers increases the electrical conductivity of the polymeric composite so formed due to high electrical conductivity, high surface area and interconnectivity of the carbon. Further, polymeric composites based on layered transition metal dichalcogenides such as molybdenum disulfide (MoS2) are also considered important because they are thin indirect band gap semiconductors with a band gap around 1.2 to 1.9eV. Amongst the various 2D materials, MoS2 has received much attention because of its unique structure consisting of a graphene-like hexagonal arrangement of Mo and S atoms stacked layer by layer to give S-Mo-S sandwiches with weak Van-der-Waal forces between them. It shows higher intrinsic fast ionic conductivity than oxides and higher theoretical capacitance than the graphite.Keywords: supercapacitor, layered transition-metal dichalcogenide, conducting polymer, ternary, carbon
Procedia PDF Downloads 2434757 Performance of Exclosure in Restoring Arid Degraded Steppes of Algeria
Authors: Kadi-Hanifi Halima, Amghar Fateh
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Steppes of arid Mediterranean zones are deeply threatened by desertification. To stop or alleviate ecological and economic problems associated with this desertification, management actions have been implemented since the last three decades. The struggle against desertification has become a national priority in many countries. In Algeria, several management techniques have been used to cope with desertification. This study aims at investigating the effect of exclosure on floristic diversity and chemical soil properties after four years of implementation. 167 phyto-ecological samples have been studied, 122 inside the exclosure and 45 outside. Results showed that plant diversity, composition, vegetation cover, pastoral value and soil fertility were significantly higher in protected areas.Keywords: desertification, arid, pastoral management, plant community soil fertility, gestation of environment, Algeria
Procedia PDF Downloads 3224756 Study on Residual Stress Measurement of Inconel-718 under Different Lubricating Conditions
Authors: M. Sandeep Kumar, Vasu Velagapudi, A. Venugopal
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When machining is carried out on a workpiece, residual stresses are induced in the workpiece due to nonuniform thermal and mechanical loads. These stresses play a vital role in the surface integrity of the final product or the output. Inconel 718 is commonly used in critical structural components of aircraft engines due to its properties at high temperatures. Therefore it is important to keep down the stresses induced due to machining. This can be achieved through proper lubricating conditions. In this work, experiments were carried out to check the influence of the developed nanofluid as cutting fluids on residual stresses developed during the course of machining. The results of MQL/Nanofluids were compared with MQL/Vegetable oil and dry machining lubricating condition. Results indicate the reduction in residual stress with the use of MQL/Nanofluid.Keywords: nanofluids, MQL, residual stress, Inconel-718
Procedia PDF Downloads 2514755 Utilization of Chicken Skin Based Products as Fat Replacers for Improving the Nutritional Quality, Physico-Chemical Characteristics and Sensory Attributes of Beef Fresh Sausage
Authors: Hussein M. H. Mohamed, Hamdy M. B. Zaki
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Fresh sausage is one of the cheapest and delicious meat products that are gaining popularity all over the world. It is considered as a practice of adding value to low-value meat cuts of high fat and connective tissue contents. One of the most important characteristics of fresh sausage is the distinctive marbling appearance between lean and fatty portions, which can be achieved by using animal fat. For achieving the marbling appearance of fresh sausage, a lager amount of fat needs to be used. The use of animal fat may represent a health concern due to its content of saturated fatty acids and trans-fats, which increase the risk of heart diseases. There is a need for reducing the fat content of fresh sausage to obtain a healthy product. However, fat is responsible for the texture, flavor, and juiciness of the product. Therefore, developing reduced-fat products is a challenging process. The main objectives of the current study were to incorporate chicken skin based products (chicken skin emulsion, gelatinized chicken skin, and gelatinized chicken skin emulsion) during the formulation of fresh sausage as fat replacers and to study the effect of these products on the nutritional quality, physicochemical properties, and sensory attributes of the processed product. Three fresh sausage formulae were prepared using chicken skin based fat replacers (chicken skin emulsion, gelatinized chicken skin, and gelatinized chicken skin emulsion) beside one formula prepared using mesenteric beef fat as a control. The proximate composition, fatty acid profiles, Physico-chemical characteristics, and sensory attributes of all formulas were assessed. The results revealed that the use of chicken skin based fat replacers resulted in significant (P < 0.05) reduction of fat contents from 17.67 % in beef mesenteric fat formulated sausage to 5.77, 8.05 and 8.46 in chicken skin emulsion, gelatinized chicken skin, and gelatinized chicken skin emulsion formulated sausages, respectively. Significant reduction in the saturated fatty acid contents and a significant increase in mono-unsaturated, poly-unsaturated, and omega-3 fatty acids have been observed in all formulae processed with chicken skin based fat replacers. Moreover, significant improvements in the physico-chemical characteristics and non-significant changes in the sensory attributes have been obtained. From the obtained results, it can be concluded that the chicken skin based products can be used safely to improve the nutritional quality and physico chemical properties of beef fresh sausages without changing the sensory attributes of the product. This study may encourage meat processors to utilize chicken skin based fat replacers for the production of high quality and healthy beef fresh sausages.Keywords: chicken skin emulsion, fresh sausage, gelatinized chicken skin, gelatinized chicken skin emulsion
Procedia PDF Downloads 1214754 Effect of Co Substitution on Structural, Magnetocaloric, Magnetic, and Electrical Properties of Sm0.6Sr0.4CoxMn1-xO3 Synthesized by Sol-gel Method
Authors: A. A. Azab
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In this work, Sm0.6Sr0.4CoxMn1-xO3 (x=0, 0.1, 0.2 and 0.3) was synthesized by sol-gel method for magnetocaloric effect (MCE) applications. XRD analysis confirmed formation of the required orthorhombic phase of perovskite, and there is crystallographic phase transition as a result of substitution. Maxwell-Wagner interfacial polarisation and Koops phenomenological theory were used to investigate and analyze the temperature and frequency dependency of the dielectric permittivity. The phase transition from the ferromagnetic to the paramagnetic state was demonstrated to be second order. Based on the isothermal magnetization curves obtained at various temperatures, the magnetic entropy change was calculated. A magnetocaloric effect (MCE) over a wide temperature range was studied by determining DSM and the relative cooling power (RCP).Keywords: magnetocaloric effect, pperovskite, magnetic phase transition, dielectric permittivity
Procedia PDF Downloads 594753 Three Macrofungi Taxa Records of Basidiomycota from Turkey
Authors: Ahmet Afyon, Dursun Yagiz, Kutret Gezer, Aziz Turkoglu
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This study was conducted in order to contribute to Turkey’s macrofungus flora. The fungi samples forming the study material were collected from Afyonkarahisar province in 2009. The photos of mushrooms were taken in their own habitats. Their tastes, odors and clours were determined. These samples were brought to the laboratory. The microscopic properties of fungi were determined in the laboratory. The fungi were identified according to their macroscopic and microscopic features with the help of written literature. The identified macrofungi are; Limacella furnace (Letell.) E.-J. Gilbert from the Amanitaceae familia, Marasmiellus vaiillantii (Pers.) Singer from Omphalotaceae familia, Mycena flos-nivium Kuhner from Mycenaceae familia. With this study, it has been contributed to Turkey’s macrofungi flora and biodiversity.Keywords: Afyonkarahisar, macrofungi, records, Turkey
Procedia PDF Downloads 3244752 The English Translation of Arabic Metaphors in the Holy Qura’n
Authors: Mohammad Hamzah Alshehab
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Metaphor is a substitute expression in everyday life in languages, thoughts and actions. It has an original value in language use with different conceptual, grammatical and properties. In addition, it is a central concept in literary studies. The present paper aims at investigating metaphor’s types imbedded in some Holy Verses (HV). For achieving the objectives of this paper, two English versions were chosen , the first is the Translation of the Meanings of the Noble Qura’n in the English Language by Mohammad AlHilali and Mohammad Khan, and the second version is the English Translation of the Holy Qura’n by Mohammad Ali were used. The researcher selected (20) Holy Verses include metaphors to be analyzed and investigated. Metaphor types were categorized by an assessment of the two translations followed by a discussion between the two versions of translation.Keywords: metaphor, metaphor’s types, Holy Qura’n, Holy Verses
Procedia PDF Downloads 6424751 Determination of Unknown Radionuclides Using High Purity Germanium Detectors
Authors: O. G. Onuk, L. S. Taura, C. M. Eze, S. M. Ngaram
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The decay chain of radioactive elements in the laboratory and the verification of natural radioactivity of the human body was investigated using the High Purity Germanium (HPGe) detector. Properties of the HPGe detectors were also investigated. The efficiency and energy resolution of HPGe detector used in the laboratory was found to be excellent. The detector was calibrated three times so as to cover a wider energy range. Also the Centroid C of the detector was found to have a linear relationship with the energies of the known gamma-rays. Using the three calibrations of the detector, the energy of an unknown radionuclide was found to follow the decay chain of thorium-232 (232Th) and it was also found that an average adult has about 2.5g Potasium-40 (40K) in the body.Keywords: detector, efficiency, energy, radionuclides, resolution
Procedia PDF Downloads 2434750 Monitoring the Effect of Deep Frying and the Type of Food on the Quality of Oil
Authors: Omar Masaud Almrhag, Frage Lhadi Abookleesh
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Different types of food like banana, potato and chicken affect the quality of oil during deep fat frying. The changes in the quality of oil were evaluated and compared. Four different types of edible oils, namely, corn oil, soybean, canola, and palm oil were used for deep fat frying at 180°C ± 5°C for 5 h/d for six consecutive days. A potato was sliced into 7-8 cm length wedges and chicken was cut into uniform pieces of 100 g each. The parameters used to assess the quality of oil were total polar compound (TPC), iodine value (IV), specific extinction E1% at 233 nm and 269 nm, fatty acid composition (FAC), free fatty acids (FFA), viscosity (cp) and changes in the thermal properties. Results showed that, TPC, IV, FAC, Viscosity (cp) and FFA composition changed significantly with time (P< 0.05) and type of food. Significant differences (P< 0.05) were noted for the used parameters during frying of the above mentioned three products.Keywords: frying potato, chicken, frying deterioration, quality of oil
Procedia PDF Downloads 4144749 Damping Optimal Design of Sandwich Beams Partially Covered with Damping Patches
Authors: Guerich Mohamed, Assaf Samir
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The application of viscoelastic materials in the form of constrained layers in mechanical structures is an efficient and cost-effective technique for solving noise and vibration problems. This technique requires a design tool to select the best location, type, and thickness of the damping treatment. This paper presents a finite element model for the vibration of beams partially or fully covered with a constrained viscoelastic damping material. The model is based on Bernoulli-Euler theory for the faces and Timoshenko beam theory for the core. It uses four variables: the through-thickness constant deflection, the axial displacements of the faces, and the bending rotation of the beam. The sandwich beam finite element is compatible with the conventional C1 finite element for homogenous beams. To validate the proposed model, several free vibration analyses of fully or partially covered beams, with different locations of the damping patches and different percent coverage, are studied. The results show that the proposed approach can be used as an effective tool to study the influence of the location and treatment size on the natural frequencies and the associated modal loss factors. Then, a parametric study regarding the variation in the damping characteristics of partially covered beams has been conducted. In these studies, the effect of core shear modulus value, the effect of patch size variation, the thickness of constraining layer, and the core and the locations of the patches are considered. In partial coverage, the spatial distribution of additive damping by using viscoelastic material is as important as the thickness and material properties of the viscoelastic layer and the constraining layer. Indeed, to limit added mass and to attain maximum damping, the damping patches should be placed at optimum locations. These locations are often selected using the modal strain energy indicator. Following this approach, the damping patches are applied over regions of the base structure with the highest modal strain energy to target specific modes of vibration. In the present study, a more efficient indicator is proposed, which consists of placing the damping patches over regions of high energy dissipation through the viscoelastic layer of the fully covered sandwich beam. The presented approach is used in an optimization method to select the best location for the damping patches as well as the material thicknesses and material properties of the layers that will yield optimal damping with the minimum area of coverage.Keywords: finite element model, damping treatment, viscoelastic materials, sandwich beam
Procedia PDF Downloads 1424748 Impact of UV on Toxicity of Zn²⁺ and ZnO Nanoparticles to Lemna minor
Authors: Gabriela Kalcikova, Gregor Marolt, Anita Jemec Kokalj, Andreja Zgajnar Gotvajn
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Since the 90’s, nanotechnology is one of the fastest growing fields of science. Nanomaterials are increasingly becoming part of many products and technologies. Metal oxide nanoparticles are among the most used nanomaterials. Zinc oxide nanoparticles (nZnO) is widely used due to its versatile properties; it has been used in products including plastics, paints, food, batteries, solar cells and cosmetic products. It is also a very effective photocatalyst used for water treatment. Such expanding application of nZnO increases their possible occurrence in the environment. In the aquatic ecosystem nZnO interact with natural environmental factors such as UV radiation, and thus it is essential to evaluate possible interaction between them. In this context, the aim of our study was to evaluate combined ecotoxicity of nZnO and Zn²⁺ on duckweed Lemna minor in presence or absence UV. Inhibition of vegetative growth of duckweed Lemna minor was monitored over a period of 7 days in multi-well plates. After the experiment, specific growth rate was determined. ZnO nanoparticles used were of primary size 13.6 ± 1.7 nm. The test was conducted with nominal nZnO and Zn²⁺ (in form of ZnCl₂) concentrations of 1, 10, 100 mg/L. Experiment was repeated with presence of natural intensity of UV (8h UV, 10 W/m² UVA, 0.5 W/m² UVB). Concentration of Zn during the test was determined by ICP-MS. In the regular experiment (absence of UV) the specific growth rate was slightly increased by low concentrations of nZnO and Zn²⁺ in comparison to control. However, 10 and 100 mg/L of Zn²⁺ resulted in 45% and 68% inhibition of the specific growth rate, respectively. In case of nZnO both concentrations (10 and 100 mg/L) resulted in similar ~ 30% inhibition and the response was not dose-dependent. The lack of the dose-response relationship is often observed in case of nanoparticles. The possible explanation is that the physical impact prevails instead of chemical ones. In the presence of UV the toxicity of Zn²⁺ was increased and 100 mg/L of Zn²⁺ caused total inhibition of the specific growth rate (100%). On the other hand, 100 mg/L of nZnO resulted in low inhibition (19%) in comparison to the experiment without UV (30%). It is thus expected, that tested nZnO is low photoactive, but could have a good UV absorption and/or reflective properties and thus protect duckweed against UV impacts. Measured concentration of Zn in the test suspension decreased only about 4% after 168h in the case of ZnCl₂. On the other hand concentration of Zn in nZnO test decreased by 80%. It is expected that nZnO were partially dissolved in the medium and at the same time agglomeration and sedimentation of particles took place and thus the concentration of Zn at the water level decreased. Results of our study indicated, that nZnO combined with UV of natural intensity does not increase toxicity of nZnO, but slightly protect the plant against UV negative effects. When Zn²⁺ and ZnO results are compared it seems that dissolved Zn plays a central role in the nZnO toxicity.Keywords: duckweed, environmental factors, nanoparticles, toxicity
Procedia PDF Downloads 3214747 Comparative Analysis of Real and Virtual Garment Fit
Authors: Kristina Ancutiene
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The goal of this research is to perform comparative analysis between the virtual fit of the woman's dress and the fit on a real person. The dress fitting was done using mechanical and structural parameters of the 100 % linen fabric and using Modaris_3D_Fit software (CAD Lectra). The dress was also sawn after which garment fit differences of real and virtual dress was researched. Four respondents whose figures were similar were used to evaluate the ease and strain deformations of the real and virtual dress. The scores that were given by the respondents wearing the real dress were compared to the ease and strain results that were given by the software. The main result was that respondents feel similar to the virtual stretch deformations but their ease feeling is not always matching the virtual ones. The results may be influenced by psychological factors and different understanding about purpose of garment.Keywords: virtual garment, 3D CAD, garment fit, mechanical properties
Procedia PDF Downloads 3254746 Determining a Suitable Maintenance Measure for Gentelligent Components Using Case-Based Reasoning
Authors: Maximilian Winkens, Peter Nyhuis
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Components with sensory properties such as gentelligent components developed at the Collaborative Research Center 653 offer a new angle on the full utilization of the remaining service life in case of a preventive maintenance. The developed methodology of component status driven maintenance analyses the stress data obtained during the component's useful life and on the basis of this knowledge assesses the type of maintenance called for in this case. The procedure is derived from the case-based reasoning method and will be elucidated in detail. The method's functionality is demonstrated with real-life data obtained during test runs of a racing car prototype.Keywords: gentelligent component, preventive maintenance, case-based reasoning, sensory
Procedia PDF Downloads 3564745 Real-Time Classification of Marbles with Decision-Tree Method
Authors: K. S. Parlak, E. Turan
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The separation of marbles according to the pattern quality is a process made according to expert decision. The classification phase is the most critical part in terms of economic value. In this study, a self-learning system is proposed which performs the classification of marbles quickly and with high success. This system performs ten feature extraction by taking ten marble images from the camera. The marbles are classified by decision tree method using the obtained properties. The user forms the training set by training the system at the marble classification stage. The system evolves itself in every marble image that is classified. The aim of the proposed system is to minimize the error caused by the person performing the classification and achieve it quickly.Keywords: decision tree, feature extraction, k-means clustering, marble classification
Procedia PDF Downloads 3744744 Chromatography Study of Fundamental Properties of Medical Radioisotope Astatine-211
Authors: Evgeny E. Tereshatov
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Astatine-211 is considered one of the most promising radionuclides for Targeted Alpha Therapy. In order to develop reliable procedures to label biomolecules and utilize efficient delivery vehicle principles, one should understand the main chemical characteristics of astatine. The short half-life of 211At (~7.2 h) and absence of any stable isotopes of this element are limiting factors towards studying the behavior of astatine. Our team has developed a procedure for rapid and efficient isolation of astatine from irradiated bismuth material in nitric acid media based on 3-octanone and 1-octanol extraction chromatography resins. This process has been automated and it takes 20 min from the beginning of the target dissolution to the At-211 fraction elution. Our next step is to consider commercially available chromatography resins and their applicability in astatine purification in the same media. Results obtained along with the corresponding sorption mechanisms will be discussed.Keywords: astatine-211, chromatography, automation, mechanism, radiopharmaceuticals
Procedia PDF Downloads 854743 Continuous Manufacturing of Ultra Fine Grained Materials by Severe Plastic Deformation Methods
Authors: Aslı Günay Bulutsuz, Mehmet Emin Yurci
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Severe plastic deformation techniques are top-down deformation methods which enable superior mechanical properties by decreasing grain size. Different kind severe plastic deformation methods have been widely being used at various process temperature and geometries. Besides manufacturing advantages of severe plastic deformation technique, most of the types are being used only at the laboratory level. They cannot be adapted to industrial usage due to their continuous manufacturability and manufacturing costs. In order to enhance these manufacturing difficulties and enable widespread usage, different kinds of methods have been developed. In this review, a comprehensive literature research was fulfilled in order to highlight continuous severe plastic deformation methods.Keywords: continuous manufacturing, severe plastic deformation, ultrafine grains, grain size refinement
Procedia PDF Downloads 2284742 The Effect of Arabic Gum on Polyethersulfone Membranes
Authors: Yehia Manawi, Viktor Kochkodan, Muataz Hussien
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In this paper, the effect of adding Arabic Gum (AG) to the dope solutions of polyethersulfone (PES) was studied. The aim of adding AG is to enhance the properties of ultrafiltration membranes such as hydrophilicity, porosity and selectivity. several AG loading (0.1-3.0 wt.%) in PES/ N-Methyl-2-pyrrolidone (NMP) casting solutions were prepared to fabricate PES membranes using phase inversion technique. The surface morphology, hydrophilicity and selectivity of the cast PES/AG membranes were analyzed using scanning electron microscopy and contact angle measurements. The selectivity of the fabricated membranes was also tested by filtration of oil solutions (1 ppm) and found to show quite high removal efficiency. The effect of adding AG to PES membranes was found to increase the permeate flux and porosity as well as reducing surface roughness and the contact angle of the membranes.Keywords: antifouling, Arabic gum, polyethersulfone membrane, ultrafiltration
Procedia PDF Downloads 2804741 Pedestrian Safe Bumper Design from Commingled Glass Fiber/Polypropylene Reinforced Sandwich Composites
Authors: L. Onal
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The aim of this study is to optimize manufacturing process for thermoplastic sandwich composite structures for the pedestrian safety of automobiles subjected to collision condition. In particular, cost-effective manufacturing techniques for sandwich structures with commingled GF/PP skins and low-density foam cores are being investigated. The performance of these structures under bending load is being studied. Samples are manufactured using compression moulding technique. The relationship of this performance to processing parameters such as mould temperature, moulding time, moulding pressure and sequence of the layers during moulding is being investigated. The results of bending tests are discussed in the light of the moulding conditions and conclusions are given regarding optimum set of processing conditions using the compression moulding routeKeywords: twintex, flexural properties, automobile composites, sandwich structures
Procedia PDF Downloads 4224740 Investigation of the Function of Chemotaxonomy of White Tea on the Regulatory Function of Genes in Pathway of Colon Cancer
Authors: Fereydoon Bondarian, Samira Shaygan
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Today, many nutritionists recommend the consumption of plants, fruits, and vegetables to provide the antioxidants needed by the body because the use of plant antioxidants usually causes fewer side effects and better treatment. Natural antioxidants increase the power of plasma antioxidants and reduce the incidence of some diseases, such as cancer. Bad lifestyles and environmental factors play an important role in increasing the incidence of cancer. In this study, different extracts of white teas taken from two types of tea available in Iran (clone 100 and Chinese hybrid) due to the presence of a hydroxyl functional group in their structure to inhibit free radicals and anticancer properties, using 3 aqueous, methanolic and aqueous-methanolic methods were used. The total polyphenolic content was calculated using the Folin-Ciocalcu method, and the percentage of inhibition and trapping of free radicals in each of the extracts was calculated using the DPPH method. With the help of high-performance liquid chromatography, a small amount of each catechin in the tea samples was obtained. Clone 100 white tea was found to be the best sample of tea in terms of all the examined attributes (total polyphenol content, antioxidant properties, and individual amount of each catechin). The results showed that aqueous and aqueous-methanolic extracts of Clone 100 white tea have the highest total polyphenol content with 27.59±0.08 and 36.67±0.54 (equivalent gallic acid per gram dry weight of leaves), respectively. Due to having the highest level of different groups of catechin compounds, these extracts have the highest property of inhibiting and trapping free radicals with 66.61±0.27 and 71.74±0.27% (mg/l) of the extracted sample against ascorbic acid). Using the MTT test, the inhibitory effect of clone 100 white tea extract in inhibiting the growth of HCT-116 colon cancer cells was investigated and the best time and concentration treatments were 500, 150 and 1000 micrograms in 8, 16 and 24 hours, respectively. To investigate gene expression changes, selected genes, including tumorigenic genes, proto-oncogenes, tumor suppressors, and genes involved in apoptosis, were selected and analyzed using the real-time PCR method and in the presence of concentrations obtained for white tea. White tea extract at a concentration of 1000 μg/ml 3 times 16, 8, and 24 hours showed the highest growth inhibition in cancer cells with 53.27, 55.8, and 86.06%. The concentration of 1000 μg/ml aqueous extract of white tea under 24-hour treatment increased the expression of tumor suppressor genes compared to the normal sample.Keywords: catechin, gene expression, suppressor genes, colon cell line
Procedia PDF Downloads 514739 Catalytic Activity of CU(II) Complex on C(SP3)-H Oxidation Reactions
Authors: Yalçın Kılıç, İbrahim Kani
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In recent years, interest in the synthesis of coordination compounds has greatly increased due to various application areas (such as catalysis, gas storage, luminescence). Dicarboxylic acids are often used in the synthesis of metal complexes. Bis-thiosalicylate derivative ligands contribute to the synthesis of structures of crystal engineering interest, as they can have both rigid and flexible properties. In addition, these ligands have great potential in terms of catalytic applications with the sulfur and oxygen donor atoms in their structures. In this study, we synthesized a Cu(II) complex [Cu(tsaxyl)(phen)2]•CH3OH (where tsaxyl = 2,2'-(1,2-phylenebis(methylene))bis(sulfanedyl)dibenzoate, phen = 1,10-phenantroline) and characterized through X-ray crystallography. The catalytic activities of Cu(II) complex on oxidation of ethylbenzene, cyclohexane, diphenylmethane, p-xylene were performed in acetonitrile with t-BuOOH as the source of oxygen.Keywords: complex, crystallography, catalysis, oxidation
Procedia PDF Downloads 98