Search results for: degradation of the cementitious composite
2635 The Potential of Tempo-Oxidized Cellulose Nanofibers to Replace Ethylene-Propylene-Diene Monomer Rubber
Authors: S. Dikmen Kucuk, A. Tozluoglu, Y. Guner
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In recent years, petroleum-based polymers began to be limited due to effects on human and environmental point of view in many countries. Thus, organic-based biodegradable materials have attracted much interest in the composite industry because of environmental concerns. As a result of this, it has been asked that inorganic and petroleum-based materials should be reduced and altered with biodegradable materials. In this point, in this study, it is aimed to investigate the potential of use of TEMPO (2,2,6,6- tetramethylpiperidine 1-oxyl)-mediated oxidation nano-fibrillated cellulose instead of EPDM (ethylene-propylene-diene monomer) rubber, which is a petroleum-based material. Thus, the exchange of petroleum-based EPDM rubber with organic based cellulose nanofibers, which are environmentally friendly (green) and biodegradable, will be realized. The effect of tempo-oxidized cellulose nanofibers (TCNF) instead of EPDM rubber was analyzed by rheological, mechanical, chemical, thermal and aging analyses. The aged surfaces were visually scrutinized and surface morphological changes were examined via scanning electron microscopy (SEM). The results obtained showed that TEMPO oxidation nano-fibrillated cellulose can be used at an amount of 1.0 and 2.2 phr resulting the values stay within tolerance according to customer standard and without any chemical degradation, crack, colour change or staining.Keywords: EPDM, cellulose, green materials, nanofibrillated cellulose, TCNF, tempo-oxidized nanofiber
Procedia PDF Downloads 1092634 Rural Water Supply Services in India: Developing a Composite Summary Score
Authors: Mimi Roy, Sriroop Chaudhuri
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Sustainable water supply is among the basic needs for human development, especially in the rural areas of the developing nations where safe water supply and basic sanitation infrastructure is direly needed. In light of the above, we propose a simple methodology to develop a composite water sustainability index (WSI) to assess the collective performance of the existing rural water supply services (RWSS) in India over time. The WSI will be computed by summarizing the details of all the different varieties of water supply schemes presently available in India comprising of 40 liters per capita per day (lpcd), 55 lpcd, and piped water supply (PWS) per household. The WSI will be computed annually, between 2010 and 2016, to elucidate changes in holistic RWSS performances. Results will be integrated within a robust geospatial framework to identify the ‘hotspots’ (states/districts) which have persistent issues over adequate RWSS coverage and warrant spatially-optimized policy reforms in future to address sustainable human development. Dataset will be obtained from the National Rural Drinking Water Program (NRDWP), operating under the aegis of the Ministry of Drinking Water and Sanitation (MoDWS), at state/district/block levels to offer the authorities a cross-sectional view of RWSS at different levels of administrative hierarchy. Due to simplistic design, complemented by spatio-temporal cartograms, similar approaches can also be adopted in other parts of the world where RWSS need a thorough appraisal.Keywords: rural water supply services, piped water supply, sustainability, composite index, spatial, drinking water
Procedia PDF Downloads 2992633 Different Processing Methods to Obtain a Carbon Composite Element for Cycling
Authors: Maria Fonseca, Ana Branco, Joao Graca, Rui Mendes, Pedro Mimoso
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The present work is focused on the production of a carbon composite element for cycling through different techniques, namely, blow-molding and high-pressure resin transfer injection (HP-RTM). The main objective of this work is to compare both processes to produce carbon composite elements for the cycling industry. It is well known that the carbon composite components for cycling are produced mainly through blow-molding; however, this technique depends strongly on manual labour, resulting in a time-consuming production process. Comparatively, HP-RTM offers a more automated process which should lead to higher production rates. Nevertheless, a comparison of the elements produced through both techniques must be done, in order to assess if the final products comply with the required standards of the industry. The main difference between said techniques lies in the used material. Blow-moulding uses carbon prepreg (carbon fibres pre-impregnated with a resin system), and the material is laid up by hand, piece by piece, on a mould or on a hard male. After that, the material is cured at a high temperature. On the other hand, in the HP-RTM technique, dry carbon fibres are placed on a mould, and then resin is injected at high pressure. After some research regarding the best material systems (prepregs and braids) and suppliers, an element was designed (similar to a handlebar) to be constructed. The next step was to perform FEM simulations in order to determine what the best layup of the composite material was. The simulations were done for the prepreg material, and the obtained layup was transposed to the braids. The selected material was a prepreg with T700 carbon fibre (24K) and an epoxy resin system, for the blow-molding technique. For HP-RTM, carbon fibre elastic UD tubes and ± 45º braids were used, with both 3K and 6K filaments per tow, and the resin system was an epoxy as well. After the simulations for the prepreg material, the optimized layup was: [45°, -45°,45°, -45°,0°,0°]. For HP-RTM, the transposed layup was [ ± 45° (6k); 0° (6k); partial ± 45° (6k); partial ± 45° (6k); ± 45° (3k); ± 45° (3k)]. The mechanical tests showed that both elements can withstand the maximum load (in this case, 1000 N); however, the one produced through blow-molding can support higher loads (≈1300N against 1100N from HP-RTM). In what concerns to the fibre volume fraction (FVF), the HP-RTM element has a slightly higher value ( > 61% compared to 59% of the blow-molding technique). The optical microscopy has shown that both elements have a low void content. In conclusion, the elements produced using HP-RTM can compare to the ones produced through blow-molding, both in mechanical testing and in the visual aspect. Nevertheless, there is still space for improvement in the HP-RTM elements since the layup of the braids, and UD tubes could be optimized.Keywords: HP-RTM, carbon composites, cycling, FEM
Procedia PDF Downloads 1322632 Smart Technology for Hygrothermal Performance of Low Carbon Material Using an Artificial Neural Network Model
Authors: Manal Bouasria, Mohammed-Hichem Benzaama, Valérie Pralong, Yassine El Mendili
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Reducing the quantity of cement in cementitious composites can help to reduce the environmental effect of construction materials. By-products such as ferronickel slags (FNS), fly ash (FA), and Crepidula fornicata (CR) are promising options for cement replacement. In this work, we investigated the relevance of substituting cement with FNS-CR and FA-CR on the mechanical properties of mortar and on the thermal properties of concrete. Foraging intervals ranging from 2 to 28 days, the mechanical properties are obtained by 3-point bending and compression tests. The chosen mix is used to construct a prototype in order to study the material’s hygrothermal performance. The data collected by the sensors placed on the prototype was utilized to build an artificial neural network.Keywords: artificial neural network, cement, circular economy, concrete, by products
Procedia PDF Downloads 1142631 Mechanical Properties of Kenaf Fibre Reinforced Epoxy Composites
Authors: C. Tezara, H. Y. Lim, M. H. Yazdi, J. W. Lim, J. P. Siregar
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Natural fibre has become an element in human lives. A lot of researchers have conducted research about natural fibre reinforced polymer. Malaysian government has spent a lot of money on the research funding for researchers and academician especially research on kenaf fibre due to exclusion of tobacco from AFTA (Asean Free Trade Area) list. This work is to investigate the mechanical properties of kenaf fiber reinforced epoxy composite where short kenaf fibre was applied and the mechanical properties of 5%, 10% and 15% wt. of kenaf fibre were added into the mixture of epoxy resin. Hand lay-up process was selected in the fabrication of the specimen for testing. The tensile, flexural and impact test were conducted following ASTM D3039, ASTM D790 and ASTM D256 accordingly. From the experiment result, the effect of different fiber loading of the specimen on its mechanical properties would be analyzed and compared in the result and discussion.Keywords: Kenaf fibre, epoxy, composite, fibre
Procedia PDF Downloads 2852630 Numerical Investigation of Soft Clayey Soil Improved by Soil-Cement Columns under Harmonic Load
Authors: R. Ziaie Moayed, E. Ghanbari Alamouty
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Deep soil mixing is one of the improvement methods in geotechnical engineering which is widely used in soft soils. This article investigates the consolidation behavior of a soft clay soil which is improved by soil-cement column (SCC) by numerical modeling using Plaxis2D program. This behavior is simulated under vertical static and cyclic load which is applied on the soil surface. The static load problem is the simulation of a physical model test in an axisymmetric condition which uses a single SCC in the model center. The results of numerical modeling consist of settlement of soft soil composite, stress on soft soil and column, and excessive pore water pressure in the soil show a good correspondence with the test results. The response of soft soil composite to the cyclic load in vertical direction also compared with the static results. Also the effects of two variables namely the cement content used in a SCC and the area ratio (the ratio of the diameter of SCC to the diameter of composite soil model, a) is investigated. The results show that the stress on the column with the higher value of a, is lesser compared with the stress on other columns. Different rate of consolidation and excessive pore pressure distribution is observed in cyclic load problem. Also comparing the results of settlement of soil shows higher compressibility in the cyclic load problem.Keywords: area ratio, consolidation behavior, cyclic load, numerical modeling, soil-cement column
Procedia PDF Downloads 1512629 Significance of Molecular Autophagic Pathway in Gaucher Disease Pathology
Authors: Ozlem Oral, Emre Taskin, Aysel Yuce, Serap Dokmeci, Devrim Gozuacik
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Autophagy is an evolutionary conserved lysosome-dependent catabolic pathway, responsible for the degradation of long-lived proteins, abnormal aggregates and damaged organelles which cannot be degraded by the ubiquitin-proteasome system. Lysosomes degrade the substrates through the activity of lysosomal hydrolases and lysosomal membrane-bound proteins. Mutations in the coding region of these proteins cause malfunctional lysosomes, which contributes to the pathogenesis of lysosomal storage diseases. Gaucher disease is a lysosomal storage disease resulting from the mutation of a lysosomal membrane-associated glycoprotein called glucocerebrosidase and its cofactor saposin C. The disease leads to intracellular accumulation of glucosylceramide and other glycolipids. Because of the essential role of lysosomes in autophagic degradation, Gaucher disease may directly be linked to this pathway. In this study, we investigated the expression of autophagy and/or lysosome-related genes and proteins in fibroblast cells isolated from patients with different mutations. We carried out confocal microscopy analysis and examined autophagic flux by utilizing the differential pH sensitivities of RFP and GFP in mRFP-GFP-LC3 probe. We also evaluated lysosomal pH by active lysosome staining and lysosomal enzyme activity. Beside lysosomes, we also performed proteasomal activity and cell death analysis in patient samples. Our data showed significant attenuation in the expression of key autophagy-related genes and accumulation of their proteins in mutant cells. We found decreased the ability of autophagosomes to fuse with lysosomes, associated with elevated lysosomal pH and reduced lysosomal enzyme activity. Proteasomal degradation and cell death analysis showed reduced proteolytic activity of the proteasome, which consequently leads to increased susceptibility to cell death. Our data indicate that the major degradation pathways are affected by multifunctional lysosomes in mutant patient cells and may underlie in the mechanism of clinical severity of Gaucher patients. (This project is supported by TUBITAK-3501-National Young Researchers Career Development Program, Project No: 112T130).Keywords: autophagy, Gaucher's disease, glucocerebrosidase, mutant fibroblasts
Procedia PDF Downloads 3242628 Application of Space Technology at Cadestral Level and Land Resources Management with Special Reference to Bhoomi Sena Project of Uttar Pradesh, India
Authors: A. K. Srivastava, Sandeep K. Singh, A. K. Kulshetra
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Agriculture is the backbone of developing countries of Asian sub-continent like India. Uttar Pradesh is the most populous and fifth largest State of India. Total population of the state is 19.95 crore, which is 16.49% of the country that is more than that of many other countries of the world. Uttar Pradesh occupies only 7.36% of the total area of India. It is a well-established fact that agriculture has virtually been the lifeline of the State’s economy in the past for long and its predominance is likely to continue for a fairly long time in future. The total geographical area of the state is 242.01 lakh hectares, out of which 120.44 lakh hectares is facing various land degradation problems. This needs to be put under various conservation and reclamation measures at much faster pace in order to enhance agriculture productivity in the State. Keeping in view the above scenario Department of Agriculture, Government of Uttar Pradesh has formulated a multi-purpose project namely Bhoomi Sena for the entire state. The main objective of the project is to improve the land degradation using low cost technology available at village level. The total outlay of the project is Rs. 39643.75 Lakhs for an area of about 226000 ha included in the 12th Five Year Plan (2012-13 to 2016-17). It is expected that the total man days would be 310.60 lakh. An attempt has been made to use the space technology like remote sensing, geographical information system, at cadastral level for the overall management of agriculture engineering work which is required for the treatment of degradation of the land. After integration of thematic maps a proposed action plan map has been prepared for the future work.Keywords: GPS, GIS, remote sensing, topographic survey, cadestral mapping
Procedia PDF Downloads 3092627 A Comparative Study on Behavior Among Different Types of Shear Connectors using Finite Element Analysis
Authors: Mohd Tahseen Islam Talukder, Sheikh Adnan Enam, Latifa Akter Lithi, Soebur Rahman
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Composite structures have made significant advances in construction applications during the last few decades. Composite structures are composed of structural steel shapes and reinforced concrete combined with shear connectors, which benefit each material's unique properties. Significant research has been conducted on different types of connectors’ behavior and shear capacity. Moreover, the AISC 360-16 “Specification for Steel Structural Buildings” consists of a formula for channel shear connectors' shear capacity. This research compares the behavior of C type and L type shear connectors using Finite Element Analysis. Experimental results from published literature are used to validate the finite element models. The 3-D Finite Element Model (FEM) was built using ABAQUS 2017 to investigate non-linear capabilities and the ultimate load-carrying potential of the connectors using push-out tests. The changes in connector dimensions were analyzed using this non-linear model in parametric investigations. The parametric study shows that by increasing the length of the shear connector by 10 mm, its shear strength increases by 21%. Shear capacity increased by 13% as the height was increased by 10 mm. The thickness of the specimen was raised by 1 mm, resulting in a 2% increase in shear capacity. However, the shear capacity of channel connectors was reduced by 21% due to an increase of thickness by 2 mm.Keywords: finite element method, channel shear connector, angle shear connector, ABAQUS, composite structure, shear connector, parametric study, ultimate shear capacity, push-out test
Procedia PDF Downloads 1252626 Identifying Dominant Anaerobic Microorganisms for Degradation of Benzene
Authors: Jian Peng, Wenhui Xiong, Zheng Lu
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An optimal recipe of amendment (nutrients and electron acceptors) was developed and dominant indigenous benzene-degrading microorganisms were characterized in this study. Lessons were learnt from the development of the optimal amendment recipe: (1) salinity and substantial initial concentration of benzene were detrimental for benzene biodegradation; (2) large dose of amendments can shorten the lag time for benzene biodegradation occurrence; (3) toluene was an essential co-substance for promoting benzene degradation activity. The stable isotope probing study identified incorporation 13C from 13C-benzene into microorganisms, which can be considered as a direct evidence of the occurrence of benzene biodegradation. The dominant mechanism for benzene removal was identified by quantitative polymerase chain reaction analysis to be nitrate reduction. Microbial analyses (denaturing gradient gel electrophoresis and 16S ribosomal RNA) demonstrated that members of genus Dokdonella spp., Pusillimonas spp., and Advenella spp. were predominant within the microbial community and involved in the anaerobic benzene bioremediation.Keywords: benzene, enhanced anaerobic bioremediation, stable isotope probing, biosep biotrap
Procedia PDF Downloads 3412625 Polyethylene Terephthalate (PET) Fabrics Decoloring for PET Textile Recycle
Authors: Chung-Yang Chuang, Hui-Min Wang, Min-Yan Dong, Chang-Jung Chang
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PET fiber is the most widely used fiber worldwide. This man-made fiber is prepared from petroleum chemicals, which may cause environmental pollution and resource exhausting issues, such as the use of non-renewable sources, greenhouse gas emission and discharge of wastewater. Therefore, the textile made by recycle-PET is the trend in the future. Recycle-PET fiber, compared with petroleum-made PET, shows lower carbon emissions and resource exhaustion. However, “fabric decoloring” is the key barrier to textile recycling. The dyes existing in the fabrics may cause PET chain degradation and appearance drawbacks during the textile recycling process. In this research, the water-based decoloring agent was used to remove the dispersed dye in the PET fabrics in order to obtain the colorless PET fabrics after the decoloring process. The decoloring rate of PET fabrics after the decoloring process was up to 99.0%. This research provides a better solution to resolve the issues of appearance and physical properties degradation of fabrics-recycle PET materials due to the residual dye. It may be possible to convert waste PET textiles into new high-quality PET fiber and build up the loop of PET textile recycling.Keywords: PET, decoloring, disperse dye, textile recycle
Procedia PDF Downloads 1402624 Charged Amphiphilic Polypeptide Based Micelle Hydrogel Composite for Dual Drug Release
Authors: Monika Patel, Kazuaki Matsumura
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Synthetic hydrogels, with their unique properties such as porosity, strength, and swelling in aqueous environment, are being used in many fields from food additives to regenerative medicines, from diagnostic and pharmaceuticals to drug delivery systems (DDS). But, hydrogels also have some limitations in terms of homogeneity of drug distribution and quantity of loaded drugs. As an alternate, polymeric micelles are extensively used as DDS. With the ease of self-assembly, and distinct stability they remarkably improve the solubility of hydrophobic drugs. However, presently, combinational therapy is the need of time and so are systems which are capable of releasing more than one drug. And it is one of the major challenges towards DDS to control the release of each drug independently, which simple DDS cannot meet. In this work, we present an amphiphilic polypeptide based micelle hydrogel composite to study the dual drug release for wound healing purposes using Amphotericin B (AmpB) and Curcumin as model drugs. Firstly, two differently charged amphiphilic polypeptide chains were prepared namely, poly L-Lysine-b-poly phenyl alanine (PLL-PPA) and poly Glutamic acid-b-poly phenyl alanine (PGA-PPA) through ring opening polymerization of amino acid N-carboxyanhydride. These polymers readily self-assemble to form micelles with hydrophobic PPA block as core and hydrophilic PLL/PGA as shell with an average diameter of about 280nm. The thus formed micelles were loaded with the model drugs. The PLL-PPA micelle was loaded with curcumin and PGA-PPA was loaded with AmpB by dialysis method. Drug loaded micelles showed a slight increase in the mean diameter and were fairly stable in solution and lyophilized forms. For forming the micelles hydrogel composite, the drug loaded micelles were dissolved and were cross linked using genipin. Genipin uses the free –NH2 groups in the PLL-PPA micelles to form a hydrogel network with free PGA-PPA micelles trapped in between the 3D scaffold formed. Different composites were tested by changing the weight ratios of the both micelles and were seen to alter its resulting surface charge from positive to negative with increase in PGA-PPA ratio. The composites with high surface charge showed a burst release of drug in initial phase, were as the composites with relatively low net charge showed a sustained release. Thus the resultant surface charge of the composite can be tuned to tune its drug release profile. Also, while studying the degree of cross linking among the PLL-PPA particles for effect on dual drug release, it was seen that as the degree of crosslinking increases, an increase in the tendency to burst release the drug (AmpB) is seen in PGA-PPA particle, were as on the contrary the PLL-PPA particles showed a slower release of Curcumin with increasing the cross linking density. Thus, two different pharmacokinetic profile of drugs were seen by changing the cross linking degree. In conclusion, a unique charged amphiphilic polypeptide based micelle hydrogel composite for dual drug delivery. This composite can be finely tuned on the basis of need of drug release profiles by changing simple parameters such as composition, cross linking and pH.Keywords: amphiphilic polypeptide, dual drug release, micelle hydrogel composite, tunable DDS
Procedia PDF Downloads 2072623 Agile Implementation of 'PULL' Principles in a Manufacturing Process Chain for Aerospace Composite Parts
Authors: Torsten Mielitz, Dietmar Schulz, York C. Roth
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Market forecasts show a significant increase in the demand for aircraft within the next two decades and production rates will be adapted accordingly. Improvements and optimizations in the industrial system are becoming more important to cope with future challenges in manufacturing and assembly. Highest quality standards have to be met for aerospace parts, whereas cost effective production in industrial systems and methodologies are also a key driver. A look at other industries like e.g., automotive shows well established processes to streamline existing manufacturing systems. In this paper, the implementation of 'PULL' principles in an existing manufacturing process chain for a large scale composite part is presented. A nonlinear extrapolation based on 'Little's Law' showed a risk of a significant increase of parts needed in the process chain to meet future demand. A project has been set up to mitigate the risk whereas the methodology has been changed from a traditional milestone approach in the beginning towards an agile way of working in the end in order to facilitate immediate benefits in the shop-floor. Finally, delivery rates could be increased avoiding more semi-finished parts in the process chain (work in progress & inventory) by the successful implementation of the 'PULL' philosophy in the shop-floor between the work stations. Lessons learned during the running project as well as implementation and operations phases are discussed in order to share best practices.Keywords: aerospace composite part manufacturing, PULL principles, shop-floor implementation, lessons learned
Procedia PDF Downloads 1722622 Climate Change, Global Warming and Future of Our Planet
Authors: Indu Gupta
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Climate change and global warming is most burning issue for “our common future”. For this common global interest. Countries organize conferences of government and nongovernment type. Human being destroying the non-renewable resources and polluting the renewable resources of planet for economic growth. Air pollution is mainly responsible for global warming and climate change .Due to global warming ice glaciers are shrinking and melting. Forests are shrinking, deserts expanding and soil eroding. The depletion of stratospheric ozone layer is depleting and hole in ozone layer that protect us from harmful ultra violet radiation. Extreme high temperature in summer and extreme low temperature and smog in winters, floods in rainy season. These all are indication of climate change. The level of carbon dioxide and other heat trapping gases in the atmosphere is increasing at high speed. Nation’s are worried about environmental degradation.Keywords: environmental degradation, global warming, soil eroding, ultra-Violate radiation
Procedia PDF Downloads 3752621 Ammonia Adsorption Properties of Composite Ammonia Carriers Obtained by Supporting Metal Chloride on Porous Materials
Authors: Cheng Shen, LaiHong Shen
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Ammonia is an important carrier of hydrogen energy, with the characteristics of high hydrogen content density and no carbon dioxide emission. Ammonia synthesis by the Haber process is the main method for industrial ammonia synthesis, but the conversion rate of ammonia per pass is only about 12%, while the conversion rate of biomass synthesis ammonia is as high as 56%. Therefore, safe and efficient ammonia capture for ammonia synthesis from biomass is an important way to alleviate the energy crisis and solve the energy problem. Metal chloride has a chemical adsorption effect on ammonia, and can be desorbed at high temperature to obtain high-concentration ammonia after combining with ammonia, which has a good development prospect in ammonia capture and separation technology. In this paper, the ammonia adsorption properties of CuCl₂ were measured, and the composite adsorbents were prepared by using silicon and multi-walled carbon nanotubes respectively to support CuCl₂, and the ammonia adsorption properties of the composite adsorbents were studied. The study found that the ammonia adsorption capacity of the three adsorbents decreased with the increase in temperature, so metal chlorides were more suitable for the low-temperature adsorption of ammonia. Silicon and multi-walled carbon nanotubes have an enhanced effect on the ammonia adsorption of CuCl₂. The reason is that the porous material itself has a physical adsorption effect on ammonia, and silicon can play the role of skeleton support in cupric chloride particles, which enhances the pore structure of the adsorbent, thereby alleviating sintering.Keywords: ammonia, adsorption properties, metal chloride, silicon, MWCNTs
Procedia PDF Downloads 1122620 The Functional Rehabilitation of Peri-Implant Tissue Defects: A Case Report
Authors: Özgür Öztürk, Cumhur Sipahi, Hande Yeşil
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Implant retained restorations commonly consist of a metal-framework veneered with ceramic or composite facings. The increasing and expanding use of indirect resin composites in dentistry is a result of innovations in materials and processing techniques. Of special interest to the implant restorative field is the possibility that composites present significantly lower peak vertical and transverse forces transmitted at the peri-implant level compared to metal-ceramic supra structures in implant-supported restorations. A 43-year-old male patient referred to the department of prosthodontics for an implant retained fixed prosthesis. The clinical and radiographic examination of the patient demonstrated the presence of an implant in the right mandibular first molar tooth region. A considerable amount of marginal bone loss around the implant was detected in radiographic examinations combined with a remarkable peri-implant soft tissue deficiency. To minimize the chewing loads transmitted to the implant-bone interface it was decided to fabricate an indirect composite resin veneered single metal crown over a screw-retained abutment. At the end of the treatment, the functional and aesthetic deficiencies were fully compensated. After a 6 months clinical and radiographic follow-up period the not any additional pathologic invasion was detected in the implant-bone interface and implant retained restoration did not reveal any vehement complication.Keywords: dental implant, fixed partial dentures, indirect composite resin, peri-implant defects
Procedia PDF Downloads 2622619 Mechanism of Cathodic Protection to Minimize Corrosion Caused by Chloride in Reinforcement Concrete
Authors: Mohamed A. Deyab, Omnia El-Shamy
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The main objective of this case study is to integrate the advantages of cathodic protection technologies in order to lessen chloride-induced corrosion in reinforced concrete. This research employs potentiodynamic polarisation, impedance spectroscopy (EIS), and surface characteristics. The results showed how effectively the new cathodic control strategy is preventing corrosion of the concrete iron rods. Over time, the protective system becomes more reliable and effective. The potentials of the zinc electrode persist still more negative after 30 days, implying that the zinc electrode can maintain powerful electrocatalytic behavior for a long period of time. As per the electrochemical impedance spectroscopy (EIS), using the CP technique reduces the rate of corrosion of rebar iron in cementitious materials over time.Keywords: cathodic protection, corrosion, reinforced concrete, chloride
Procedia PDF Downloads 862618 Production and Quality Assessment of Antioxidant-Rich Biscuit Produced from Pearl Millet and Orange Peel Flour Blends
Authors: Oloniyo Rebecca Olajumoke
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The unstable free radicals molecules oxidize cells throughout the body to cause oxidative stress, which has been implicated in the pathogenesis of many chronic diseases. Thus, the consumption of antioxidant-rich snacks could help to reduce the production of these free radicals in the body. This study aimed at producing antioxidant–rich biscuits from an underutilized pearl millet and agricultural waste from orange peel flour (PMF and OPF, respectively) blends. Biscuits were produced from PMF, and OPF blends using various proportions (95:05; 90:10; 85:15; 80:20 with 100% PMF as control. The functional properties of the flours, as well as the antioxidant properties, physical evaluation, and consumer acceptability of the biscuits, were evaluated. The functional properties of the composite flour showed an increase in oil absorption capacity (7.73-8.80 g/ml), water absorption capacity (6.82-7.21 g/ml), foaming (3.91-5.88 g/ml), and emulsification (52.85-58.82 g/ml) properties. The increased addition of OPF significantly (p<0.05) increased the antioxidant properties of the biscuits produced from the composite flour. For instance, the ferric reducing properties (0.10-0.4 mgAAE/g), total flavonoid (1.20-8.12 mg QE/g), and ABTS radical scavenging (1.17-2.19 mmol/TEAC/g) of the composite flours were increasingly comparable to those of 100% PMF. The physical parameters of the biscuit were significantly different (p<0.05) from one another. The addition of OPF into PMF reduced the weight, diameter, and spread ratio of biscuits produced while contrarily increasing the height of the biscuit. The incorporation of OPF at 5% (95:05) substitution yielded a consumedly acceptable biscuit product. The significant increase in antioxidant properties with an increase in OPF during the production of biscuits would therefore increase the nutritional value and potential health benefits.Keywords: orange peel, biscuit, antioxidant, pearl millet
Procedia PDF Downloads 952617 Mechanical Properties of Sugar Palm Fibre Reinforced Thermoplastic Polyurethane Composites
Authors: Dandi Bachtiar, Mohammed Ausama Abbas, Januar Parlaungan Siregar, Mohd Ruzaimi Bin Mat Rejab
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Short sugar palm fibre and thermoplastic polyurethane were combined to produce new composites by using the extrude method. Two techniques used to prepare a new composite material, firstly, extrusion of the base material with short fibre, secondly hot pressing them. The size of sugar palm fibre was fixed at 250µm. Different weight percent (10 wt%, 20 wt% and 30 wt%) were used in order to optimise preparation process. The optimization of process depended on the characterization mechanical properties such as impact, tensile, and flexural of the new (TPU/SPF) composite material. The results proved that best tensile and impact properties of weight additive fibre applied 10 wt%. There was an increasing trend recorded of flexural properties during increased the fibre loading. Meanwhile, the maximum tensile strength was 14.0 MPa at 10 wt% of the fibre. Moreover, there was no significant effect for additions more than 30 wt% of the fibre.Keywords: composites, natural fibre, polyurethane, sugar palm
Procedia PDF Downloads 3842616 Properties of Composite Materials Made from Surface Treated Particles from Annual Plants
Authors: Štěpán Hýsek, Petra Gajdačová, Milan Podlena
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Annual plants are becoming more and more popular source of lignin and cellulose. In those days a lot of research is carried out in order to evaluate the possibility of utilization of fibres and particles from these plants in composite materials production. These lingo-cellulosic materials seem to be a great alternative to wood, however, due to waxy and silica layers on the surface of these stalks, one additional technological step is needed–erosion of the layers for the purpose of achieving better adhesion between particle and adhesive. In this research, we used several kinds of particle pre-treatment, in order to modify surface properties of these particles. Further, an adhesive was applied to the particles using laboratory blender and board were produced using laboratory press. Both physical and mechanical properties of boards were observed. It was found out that the surface modification of particles had statistically significant effect on properties of produced boards.Keywords: annual plant, composites, mechanical properties, particleboard
Procedia PDF Downloads 1982615 Predicting and Optimizing the Mechanical Behavior of a Flax Reinforced Composite
Authors: Georgios Koronis, Arlindo Silva
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This study seeks to understand the mechanical behavior of a natural fiber reinforced composite (epoxy/flax) in more depth, utilizing both experimental and numerical methods. It is attempted to identify relationships between the design parameters and the product performance, understand the effect of noise factors and reduce process variations. Optimization of the mechanical performance of manufactured goods has recently been implemented by numerous studies for green composites. However, these studies are limited and have explored in principal mass production processes. It is expected here to discover knowledge about composite’s manufacturing that can be used to design artifacts that are of low batch and tailored to niche markets. The goal is to reach greater consistency in the performance and further understand which factors play significant roles in obtaining the best mechanical performance. A prediction of response function (in various operating conditions) of the process is modeled by the DoE. Normally, a full factorial designed experiment is required and consists of all possible combinations of levels for all factors. An analytical assessment is possible though with just a fraction of the full factorial experiment. The outline of the research approach will comprise of evaluating the influence that these variables have and how they affect the composite mechanical behavior. The coupons will be fabricated by the vacuum infusion process defined by three process parameters: flow rate, injection point position and fiber treatment. Each process parameter is studied at 2-levels along with their interactions. Moreover, the tensile and flexural properties will be obtained through mechanical testing to discover the key process parameters. In this setting, an experimental phase will be followed in which a number of fabricated coupons will be tested to allow for a validation of the design of the experiment’s setup. Finally, the results are validated by performing the optimum set of in a final set of experiments as indicated by the DoE. It is expected that after a good agreement between the predicted and the verification experimental values, the optimal processing parameter of the biocomposite lamina will be effectively determined.Keywords: design of experiments, flax fabrics, mechanical performance, natural fiber reinforced composites
Procedia PDF Downloads 2042614 Nanofluid based on Zinc Oxide/Ferric Oxide Nanocomposite as Additive for Geothermal Drilling Fluids
Authors: Anwaar O. Ali, Mahmoud Fathy Mubarak, Mahmoud Ibrahim Abdou, Hector Cano Esteban, Amany A. Aboulrous
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Corrosion resistance and lubrication are crucial characteristics required for geothermal drilling fluids. In this study, a ZnO/Fe₂O₃ nanocomposite was fabricated and incorporated into the structure of Cetyltrimethylammonium bromide (CTAB). Several physicochemical techniques were utilized to analyze and describe the synthesized nanomaterials. The surface morphology of the composite was assessed through scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDAX). The corrosion inhibition capabilities of these materials were explored across various corrosive environments. The weight loss and electrochemical methods were utilized to determine the corrosion inhibition activity of the prepared nanomaterials. The results demonstrate a high level of protection achieved by the composite. Additionally, the lubricant coefficient and extreme pressure properties were evaluated.Keywords: nanofluid, corrosion, geothermal drilling fluids, ZnO/Fe2O3
Procedia PDF Downloads 702613 Experimental Setup of Corona Discharge on Dye Degradation for Science Education
Authors: Shivam Dubey, Vinit Srivastava, Abhay Singh Thakur, Rahul Vaish
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The presence of organic dyes in water is a critical issue that poses a significant threat to the environment and human health. We have investigated the use of corona discharge as a potential method for degrading organic dyes in water. Methylene Blue dye was exposed to corona discharge, and its photo-absorbance was measured over time to determine the extent of degradation. The results depicted a decreased absorbance for the dye and the loss of the characteristic colour of methylene blue. The effects of various parameters, including current, voltage, gas phase, salinity, and electrode spacing, on the reaction rates, were investigated. The highest reaction rates were observed at the highest current and voltage (up to 10kV), lowest salinity, smallest electrode spacing, and an environment containing enhanced levels of oxygen. These findings have possible applications for science education curriculum. By investigating the use of corona discharge for destroying organic dyes, we can provide students with a practical application of scientific principles that they can apply to real-world problems. This research can demonstrate the importance of understanding the chemical and physical properties of organic dyes and the effects of corona discharge on their degradation and provide a holistic understanding of the applications of scientific research. Moreover, our study also emphasizes the importance of considering the various parameters that can affect reaction rates. By investigating the effects of current, voltage, matter phase, salinity, and electrode spacing, we can provide students with an opportunity to learn about the importance of experimental design and how to evade constraints that can limit meaningful results. In conclusion, this study has the potential to provide valuable insights into the use of corona discharge for destroying organic dyes in water and has significant implications for science education. By highlighting the practical applications of scientific principles, experimental design, and the importance of considering various parameters, this research can help students develop critical thinking skills and prepare them for future careers in science and engineering.Keywords: dye degradation, corona discharge, science education, hands-on learning, chemical education
Procedia PDF Downloads 692612 Use of Low-Cost Hydrated Hydrogen Sulphate-Based Protic Ionic Liquids for Extraction of Cellulose-Rich Materials from Common Wheat (Triticum Aestivum) Straw
Authors: Chris Miskelly, Eoin Cunningham, Beatrice Smyth, John. D. Holbrey, Gosia Swadzba-Kwasny, Emily L. Byrne, Yoan Delavoux, Mantian Li.
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Recently, the use of ionic liquids (ILs) for the preparation of lignocellulose derived cellulosic materials as alternatives to petrochemical feedstocks has been the focus of considerable research interest. While the technical viability of IL-based lignocellulose treatment methodologies has been well established, the high cost of reagents inhibits commercial feasibility. This work aimed to assess the technoeconomic viability of the preparation of cellulose rich materials (CRMs) using protic ionic liquids (PILs) synthesized from low cost alkylamines and sulphuric acid. For this purpose, the tertiary alkylamines, triethylamine, and dimethylbutylamine were selected. Bulk scale production cost of the synthesized PILs, triethylammonium hydrogen sulphate and dimetheylbutylammonium hydrogen sulphate, was reported as $0.78 kg-1 to $1.24 kg-1. CRMs were prepared through the treatment of common wheat (Triticum aestivum) straw with these PILs. By controlling treatment parameters, CRMs with a cellulose content of ≥ 80 wt% were prepared. This was achieved using a T. aestivum straw to PIL loading ratio of 1:15 w/w, a treatment duration of 180 minutes, and ethanol as a cellulose antisolvent. Infrared spectra data and decreased onset degradation temperature of CRMs (ΔTONSET ~ 70 °C) suggested the formation of cellulose sulphate esters during treatment. Chemical derivatisation can aid the dispersion of prepared CRMs in non-polar polymer/ composite matrices, but act as a barrier to thermal processing at temperatures above 150 °C. It was also shown that treatment increased the crystallinity of CRMs (ΔCrI ~ 40 %) without altering the native crystalline structure or crystallite size (~ 2.6 nm) of cellulose; peaks associated with the cellulose I crystalline planes (110), (200), and (004) were observed at Bragg angles 16.0 °, 22.5 ° and 35.0 ° respectively. This highlighted the inability of assessed PILs to dissolve crystalline cellulose and was attributed to the high acidity (pKa ~ - 1.92 to - 6.42) of sulphuric acid derived anions. Electron micrographs revealed that the stratified multilayer tissue structure of untreated T. aestivum straw was significantly modified during treatment. T. aestivum straw particles were disassembled during treatment, with prepared CRMs adopting a golden-brown film-like appearance. This work demonstrated the degradation of non-cellulosic fractions of lignocellulose without dissolution of cellulose. It is the first to report on the derivatisation of cellulose during treatment with protic hydrogen sulphate ionic liquids, and the potential implications of this with reference to biopolymer feedstock preparation.Keywords: cellulose, extraction, protic ionic liquids, esterification, thermal stability, waste valorisation, biopolymer feedstock
Procedia PDF Downloads 362611 Assessment of the Thermal and Mechanical Properties of Bio-based Composite Materials for Thermal Insulation
Authors: Nega Tesfie Asfaw, Rafik Absi, Labouda B. A, Ikram El Abbassi
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Composite materials have come to the fore a few decades ago because of their superior insulation performances. Recycling natural fiber composites and natural fiber reinforcement of waste materials are other steps for conserving resources and the environment. This paper reviewed the Thermal properties (Thermal conductivity, Effusivity, and Diffusivity) and Mechanical properties (Compressive strength, Flexural strength, and Tensile strength) of bio-composite materials for thermal insulation in the construction industry. For several years, the development of the building materials industry has placed a special emphasis on bio-source materials. According to recent studies, most natural fibers have good thermal insulating qualities and good mechanical properties. To determine the thermal and mechanical performance of bio-composite materials in construction most research used experimental methods. the results of the study show that these natural fibers have allowed us to optimize energy consumption in a building and state that density, porosity, percentage of fiber, the direction of heat flow orientation of the fiber, and the shape of the specimen are the main elements that limit the thermal performance and also showed that density, porosity, Type of Fiber, Fiber length, orientation and weight percentage loading, Fiber-matrix adhesion, Choice of the polymer matrix, Presence of void are the main elements that limit the mechanical performance of the insulation material. Based on the results of this reviewed paper Moss fibers (0.034W/ (m. K)), Wood Fiber (0.043 W/ (m. K)), Wheat straw (0.046 W/ (m. K), and corn husk fibers (0.046 W/ (m. K) are a most promising solution for energy efficiency for construction industry with interesting insulation properties and with good acceptable mechanical properties. Finally, depending on the best fibers used for insulation applications in the construction sector, the thermal performance rate of various fibers reviewed in this article are analyzed. Due to Typha's high porosity, the results indicated that Typha australis fiber had a better thermal performance rate of 89.03% with clay.Keywords: bio-based materials, thermal conductivity, compressive strength, thermal performance
Procedia PDF Downloads 272610 Development of a Table-Top Composite Wire Fabrication System for Additive Manufacturing
Authors: Krishna Nand, Mohammad Taufik
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Fused Filament Fabrication (FFF) is one of the most popular additive manufacturing (AM) technology. In FFF technology, a wire form material (filament) is fed inside a heated chamber, where it gets converted into semi-solid form and extruded out of a nozzle to be deposited on the build platform to fabricate the part. FFF technology is expanding and covering the market at a very rapid rate, so the need of raw materials for 3D printing is also increasing. The cost of 3D printing is directly affected by filament cost. To make 3D printing more economic, a compact and portable filament/wire extrusion system is needed. Wire extrusion systems to extrude ordinary wire/filament made of a single material are available in the market. However, extrusion system to make a composite wire/filament are not available. Hence, in this study, initial efforts have been made to develop a table-top composite wire extruder. The developed system is consisted of mechanical parts, electronics parts, and a control system. A multiple channel hopper, extrusion screw, melting chamber and nozzle, cooling zone, and spool winder are some mechanical parts. While motors, heater, temperature sensor, cooling fans are some electronics parts, which are used to develop this system. A control board has been used to control the various process parameters like – temperature and speed of motors. For the production of composite wire/filament, two different materials could be fed through two channels of hopper, which will be mixed and carried to the heated zone by extrusion screw. The extrusion screw is rotated by a motor, and the speed of this motor will be controlled by the controller as per the requirement of material extrusion rate. In the heated zone, the material will melt with the help of a heating element and extruded out of the nozzle in the form of wire. The developed system occupies less floor space due to the vertical orientation of its heating chamber. It is capable to extrude ordinary filament as well as composite filament, which are compatible with 3D printers available in the market. Further, the developed system could be employed in the research and development of materials, processing, and characterization for 3D printer. The developed system presented in this study could be a better choice for hobbyists and researchers dealing with the fused filament fabrication process to reduce the 3D printing cost significantly by recycling the waste material into 3D printer feed material. Further, it could also be explored as a better alternative for filament production at the commercial level.Keywords: additive manufacturing, 3D Printing, filament extrusion, pellet extrusion
Procedia PDF Downloads 1682609 Forest Degradation and Implications for Rural Livelihood in Kaimur Reserve Forest of Bihar, India
Authors: Shashi Bhushan, Sucharita Sen
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In India, forest and people are inextricably linked since millions of people live adjacent to or within protected areas and harvest forest products. Indian forest has their own legacy to sustain by its own climatic nature with several social, economic and cultural activities. People surrounding forest areas are not only dependent on this resource for their livelihoods but also for the other source, like religious ceremonies, social customs and herbal medicines, which are determined by the forest like agricultural land, groundwater level, and soil fertility. The assumption that fuelwood and fodder extraction, which is the part of local livelihood leads to deforestation, has so far been the dominant mainstream views in deforestation discourses. Given the occupational division across social groups in Kaimur reserve forest, the differential nature of dependence of forest resources is important to understand. This paper attempts to assess the nature of dependence and impact of forest degradation on rural households across various social groups. Also, an additional element that is added to the enquiry is the way degradation of forests leading to scarcity of forest-based resources impacts the patterns of dependence across various social groups. Change in forest area calculated through land use land cover analysis using remote sensing technique and examination of different economic activities carried out by the households that are forest-based was collected by primary survey in Kaimur reserve forest of state of Bihar in India. The general finding indicates that the Scheduled Tribe and Scheduled Caste communities, the most socially and economically deprived sections of the rural society are involved in a significant way in collection of fuelwood, fodder, and fruits, both for self-consumption and sale in the market while other groups of society uses fuelwood, fruit, and fodder for self-use only. Depending on the local forest resources for fuelwood consumption was the primary need for all social groups due to easy accessibility and lack of alternative energy source. In last four decades, degradation of forest made a direct impact on rural community mediated through the socio-economic structure, resulting in a shift from forest-based occupations to cultivation and manual labour in agricultural and non-agricultural activities. Thus there is a need to review the policies with respect to the ‘community forest management’ since this study clearly throws up the fact that engagement with and dependence on forest resources is socially differentiated. Thus tying the degree of dependence and forest management becomes extremely important from the view of ‘sustainable’ forest resource management. The statization of forest resources also has to keep in view the intrinsic way in which the forest-dependent population interacts with the forest.Keywords: forest degradation, livelihood, social groups, tribal community
Procedia PDF Downloads 1692608 Investigation of the Progressive Collapse Potential in Steel Buildings with Composite Floor System
Authors: Pouya Kaafi, Gholamreza Ghodrati Amiri
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Abnormal loads due to natural events, implementation errors and some other issues can lead to occurrence of progressive collapse in structures. Most of the past researches consist of 2- Dimensional (2D) models of steel frames without consideration of the floor system effects, which reduces the accuracy of the modeling. While employing a 3-Dimensional (3D) model and modeling the concrete slab system for the floors have a crucial role in the progressive collapse evaluation. In this research, a 3D finite element model of a 5-story steel building is modeled by the ABAQUS software once with modeling the slabs, and the next time without considering them. Then, the progressive collapse potential is evaluated. The results of the analyses indicate that the lack of the consideration of the slabs during the analyses, can lead to inaccuracy in assessing the progressive failure potential of the structure.Keywords: abnormal loads, composite floor system, intermediate steel moment resisting frame system, progressive collapse
Procedia PDF Downloads 4562607 Influence of Nano-ATH on Electrical Performance of LSR for HVDC Insulation
Authors: Ju-Na Hwang, Min-Hae Park, Kee-Joe Lim
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Many studies have been conducted on DC transmission. Of power apparatus for DC transmission, High Voltage Direct Current (HVDC) cable systems are being evaluated because of the increase in power demand and transmission distance. Therefore, dc insulation characteristics of Liquid Silicone Rubber (LSR), which has various advantages such as short curing time and the ease of maintenance, were investigated to assess its performance as a HVDC insulation material for cable joints. The electrical performance of LSR added to Nano-Aluminum Trihydrate (ATH) was confirmed by measurements of the breakdown strength and electrical conductivity. In addition, field emission scanning electron microscope (FE-SEM) was used as a means of confirmation of nano-filler dispersion state. The LSR nano-composite was prepared by compounding LSR filled nano-sized ATH filler. The DC insulation properties of LSR added to nano-sized ATH fillers were found to be superior to those of the LSR without filler.Keywords: liquid silicone rubber, nano-composite, HVDC insulation, cable joints
Procedia PDF Downloads 4622606 High Temperature Oxidation of Additively Manufactured Silicon Carbide/Carbon Fiber Nanocomposites
Authors: Saja M. Nabat Al-Ajrash, Charles Browning, Rose Eckerle, Li Cao, Robyn L. Bradford, Donald Klosterman
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An additive manufacturing process and subsequent pyrolysis cycle were used to fabricate SiC matrix/carbon fiber hybrid composites. The matrix was fabricated using a mixture of preceramic polymer and acrylate monomers, while polyacrylonitrile (PAN) precursor was used to fabricate fibers via electrospinning. The precursor matrix and reinforcing fibers at 0, 2, 5, or 10 wt% were printed using digital light processing, and both were simultaneously pyrolyzed to yield the final ceramic matrix composite structure. After pyrolysis, XRD and SEAD analysis proved the existence of SiC nanocrystals and turbostratic carbon structure in the matrix, while the reinforcement phase was shown to have a turbostratic carbon structure similar to commercial carbon fibers. Thermogravimetric analysis (TGA) in the air up to 1400 °C was used to evaluate the oxidation resistance of this material. TGA results showed some weight loss due to oxidation of SiC and/or carbon up to about 900 °C, followed by weight gain to about 1200 °C due to the formation of a protective SiO2 layer. Although increasing carbon fiber content negatively impacted the total mass loss for the first heating cycle, exposure of the composite to second-run air revealed negligible weight chance. This is explained by SiO2 layer formation, which acts as a protective film that prevents oxygen diffusion. Oxidation of SiC and the formation of a glassy layer has been proven to protect the sample from further oxidation, as well as provide healing of surface cracks and defects, as revealed by SEM analysis.Keywords: silicon carbide, carbon fibers, additive manufacturing, composite
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