Search results for: black carbon
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3798

Search results for: black carbon

948 Biosensor Design through Molecular Dynamics Simulation

Authors: Wenjun Zhang, Yunqing Du, Steven W. Cranford, Ming L. Wang

Abstract:

The beginning of 21st century has witnessed new advancements in the design and use of new materials for biosensing applications, from nano to macro, protein to tissue. Traditional analytical methods lack a complete toolset to describe the complexities introduced by living systems, pathological relations, discrete hierarchical materials, cross-phase interactions, and structure-property dependencies. Materiomics – via systematic molecular dynamics (MD) simulation – can provide structure-process-property relations by using a materials science approach linking mechanisms across scales and enables oriented biosensor design. With this approach, DNA biosensors can be utilized to detect disease biomarkers present in individuals’ breath such as acetone for diabetes. Our wireless sensor array based on single-stranded DNA (ssDNA)-decorated single-walled carbon nanotubes (SWNT) has successfully detected trace amount of various chemicals in vapor differentiated by pattern recognition. Here, we present how MD simulation can revolutionize the way of design and screening of DNA aptamers for targeting biomarkers related to oral diseases and oral health monitoring. It demonstrates great potential to be utilized to build a library of DNDA sequences for reliable detection of several biomarkers of one specific disease, and as well provides a new methodology of creating, designing, and applying of biosensors.

Keywords: biosensor, DNA, biomarker, molecular dynamics simulation

Procedia PDF Downloads 459
947 Photo Electrical Response in Graphene Based Resistive Sensor

Authors: H. C. Woo, F. Bouanis, C. S. Cojocaur

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Graphene, which consists of a single layer of carbon atoms in a honeycomb lattice, is an interesting potential optoelectronic material because of graphene’s high carrier mobility, zero bandgap, and electron–hole symmetry. Graphene can absorb light and convert it into a photocurrent over a wide range of the electromagnetic spectrum, from the ultraviolet to visible and infrared regimes. Over the last several years, a variety of graphene-based photodetectors have been reported, such as graphene transistors, graphene-semiconductor heterojunction photodetectors, graphene based bolometers. It is also reported that there are several physical mechanisms enabling photodetection: photovoltaic effect, photo-thermoelectric effect, bolometric effect, photogating effect, and so on. In this work, we report a simple approach for the realization of graphene based resistive photo-detection devices and the measurements of their photoelectrical response. The graphene were synthesized directly on the glass substrate by novel growth method patented in our lab. Then, the metal electrodes were deposited by thermal evaporation on it, with an electrode length and width of 1.5 mm and 300 μm respectively, using Co to fabricate simple graphene based resistive photosensor. The measurements show that the graphene resistive devices exhibit a photoresponse to the illumination of visible light. The observed re-sistance response was reproducible and similar after many cycles of on and off operations. This photoelectrical response may be attributed not only to the direct photocurrent process but also to the desorption of oxygen. Our work shows that the simple graphene resistive devices have potential in photodetection applications.

Keywords: graphene, resistive sensor, optoelectronics, photoresponse

Procedia PDF Downloads 285
946 Optimization of Highly Oriented Pyrolytic Graphite Crystals for Neutron Optics

Authors: Hao Qu, Xiang Liu, Michael Crosby, Brian Kozak, Andreas K. Freund

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The outstanding performance of highly oriented pyrolytic graphite (HOPG) as an optical element for neutron beam conditioning is unequaled by any other crystalline material in the applications of monochromator, analyzer, and filter. This superiority stems from the favorable nuclear properties of carbon (small absorption and incoherent scattering cross-sections, big coherent scattering length) and the specific crystalline structure (small thermal diffuse scattering cross-section, layered crystal structure). The real crystal defect structure revealed by imaging techniques is correlated with the parameters used in the mosaic model (mosaic spread, mosaic block size, uniformity). The diffraction properties (rocking curve width as determined by both the intrinsic mosaic spread and the diffraction process, peak and integrated reflectivity, filter transmission) as a function of neutron wavelength or energy can be predicted with high accuracy and reliability by diffraction theory using empirical primary extinction coefficients extracted from a great amount of existing experimental data. The results of these calculations are given as graphs and tables permitting to optimize HOPG characteristics (mosaic spread, thickness, curvature) for any given experimental situation.

Keywords: neutron optics, pyrolytic graphite, mosaic spread, neutron scattering, monochromator, analyzer

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945 Bioremediation of Disposed X-Ray Film for Nanoparticles Production

Authors: Essam A. Makky, Siti H. Mohd Rasdi, J. B. Al-Dabbagh, G. F. Najmuldeen

Abstract:

The synthesis of silver nano particles (SNPs) extensively studied by using chemical and physical methods. Here, the biological methods were used and give benefits in research field in the aspect of very low cost (from waste to wealth) and safe time as well. The study aims to isolate and exploit the microbial power in the production of industrially important by-products in nano-size with high economic value, to extract highly valuable materials from hazardous waste, to quantify nano particle size, and characterization of SNPs by X-Ray Diffraction (XRD) analysis. Disposal X-ray films were used as substrate because it consumes about 1000 tons of total silver chemically produced worldwide annually. This silver is being wasted when these films are used and disposed. Different bacterial isolates were obtained from various sources. Silver was extracted as nano particles by microbial power degradation from disposal X-ray film as the sole carbon source for ten days incubation period in darkness. The protein content was done and all the samples were analyzed using XRD, to characterize of silver (Ag) nano particles size in the form of silver nitrite. Bacterial isolates CL4C showed the average size of SNPs about 19.53 nm, GL7 showed average size about 52.35 nm and JF Outer 2A (PDA) showed 13.52 nm. All bacterial isolates partially identified using Gram’s reaction and the results obtained exhibited that belonging to Bacillus sp.

Keywords: nanotechnology, bioremediation, disposal X-ray film, nanoparticle, waste, XRD

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944 Perfluoroheptanoic Acid Affects Xenopus Embryo Embryogenesis by Inducing the Phosphorylation of ERK and JNK

Authors: Chowon Kim, Yoo-Kyung Kim, Kyeong Yeon Park, Hyun-Shik Lee

Abstract:

Perfluoroalkyl compounds (PFCs) are globally distributed synthetic compounds that are known to adversely affect human health. Developmental toxicity assessment of PFCs is important to facilitate the evaluation of their environmental impact. In the present study, we assessed the developmental toxicity and teratogenicity of PFCs with different numbers of carbon atoms on Xenopus embryogenesis. An initial frog embryo teratogenicity assay-Xenopus (FETAX) assay was performed that identified perfluorohexanoic (PFHxA) and perfluoroheptanoic (PFHpA) acids as potential teratogens and developmental toxicants. The mechanism underlying this teratogenicity was also investigated by measuring the expression of tissue-specific biomarkers such as phosphotyrosine‑binding protein, xPTB (liver); NKX2.5 (heart); and Cyl18 (intestine). Whole‑mount in situ hybridization, reverse transcriptase‑polymerase chain reaction (RT-PCR), and histologic analyses detected severe defects in the liver and heart following exposure to PFHxA or PFHpA. In addition, immunoblotting revealed that PFHpA significantly increased the phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), while PFHxA slightly increased these, as compared with the control. These results suggest that PFHxA and PFHpA are developmental toxicants and teratogens, with PFHpA producing more severe effects on liver and heart development through the induction of ERK and JNK phosphorylation.

Keywords: PFCs, ERK, JNK, xenopus

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943 Effects of Porcine Oviductal Fluid on In vitro Growth of Dendrobium mirbelianum

Authors: M. Youngsabanant-Areekijseree, C. Thepsithar, K. Sribuddhachart, J. Tananantayot

Abstract:

Porcine oviductal fluid (pOF) from oviduct, an unused organ from the slaughterhouse, was effectively used for biotechnology studies. The fluid components consisted of micro- and macro-nutrients, amino acids, carbon source and proteins that played important roles in animal cell and embryo development. This was our knowledge on investigating pOF as growth promoting substance in culture medium of an orchid, Dendrobium mirbelianum. Two-leaf shoots were cultured in liquid Vacin and Went (VW) medium as a standard medium supplemented with 2 g/L peptone (Pe) or 100 g/ L boiled-potato water (Po) alone or in combinations, and added with 0, 1, 3 or 5 ml/L pOF. All explants were cultured in a stationary condition for 8 weeks. It was found that medium added with 100 g/L Po and 1 ml/L pOF provided the best results (1.02 g fresh weight, 4.2 shoots, 0.53 cm shoot height, 4.4 protocorms, 11.0 leaves and 5.7 roots with 100% survival) when compared to other medium, but not statistically significant difference from medium added with 100 g/L Po (0.86 g fresh weight, 4.3 shoots, 0.51 cm shoot height, 4.6 protocorms, 12.4 leaves and 6.6 roots with 100% survival). However, VW medium supplemented with 1 or 3 ml/L pOF alone showed the higher percentage of survival (100%) than VW medium (86.67%). It was shown the potential role of pOF as an organic supplement for promoting growth of plants. Acknowledgements—The project was funded by a grant from Silpakorn University Research & Development Institute (SURDI) and Faculty of Science, Silpakorn University, Thailand.

Keywords: Dendrobium mirbelianum, pig, oviductal fluid, in vitro growth

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942 Hybrid Model: An Integration of Machine Learning with Traditional Scorecards

Authors: Golnush Masghati-Amoli, Paul Chin

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Over the past recent years, with the rapid increases in data availability and computing power, Machine Learning (ML) techniques have been called on in a range of different industries for their strong predictive capability. However, the use of Machine Learning in commercial banking has been limited due to a special challenge imposed by numerous regulations that require lenders to be able to explain their analytic models, not only to regulators but often to consumers. In other words, although Machine Leaning techniques enable better prediction with a higher level of accuracy, in comparison with other industries, they are adopted less frequently in commercial banking especially for scoring purposes. This is due to the fact that Machine Learning techniques are often considered as a black box and fail to provide information on why a certain risk score is given to a customer. In order to bridge this gap between the explain-ability and performance of Machine Learning techniques, a Hybrid Model is developed at Dun and Bradstreet that is focused on blending Machine Learning algorithms with traditional approaches such as scorecards. The Hybrid Model maximizes efficiency of traditional scorecards by merging its practical benefits, such as explain-ability and the ability to input domain knowledge, with the deep insights of Machine Learning techniques which can uncover patterns scorecard approaches cannot. First, through development of Machine Learning models, engineered features and latent variables and feature interactions that demonstrate high information value in the prediction of customer risk are identified. Then, these features are employed to introduce observed non-linear relationships between the explanatory and dependent variables into traditional scorecards. Moreover, instead of directly computing the Weight of Evidence (WoE) from good and bad data points, the Hybrid Model tries to match the score distribution generated by a Machine Learning algorithm, which ends up providing an estimate of the WoE for each bin. This capability helps to build powerful scorecards with sparse cases that cannot be achieved with traditional approaches. The proposed Hybrid Model is tested on different portfolios where a significant gap is observed between the performance of traditional scorecards and Machine Learning models. The result of analysis shows that Hybrid Model can improve the performance of traditional scorecards by introducing non-linear relationships between explanatory and target variables from Machine Learning models into traditional scorecards. Also, it is observed that in some scenarios the Hybrid Model can be almost as predictive as the Machine Learning techniques while being as transparent as traditional scorecards. Therefore, it is concluded that, with the use of Hybrid Model, Machine Learning algorithms can be used in the commercial banking industry without being concerned with difficulties in explaining the models for regulatory purposes.

Keywords: machine learning algorithms, scorecard, commercial banking, consumer risk, feature engineering

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941 Effect of Nanoscale Bismuth Oxide on Radiation Shielding and Interaction Characteristics of Polyvinyl Alcohol-Based Polymer for Medical Apron Design

Authors: E. O. Echeweozo

Abstract:

This study evaluated radiation shielding and interaction characteristics of polyvinyl alcohol (PVA) polymer separately doped with 10% and 20% nanoscale Bi₂O₃, respectively, for medical apron design and shielding special electronic installations. Prepared samples were characterized by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The EDS results showed that Carbon (C), Oxygen (O), and bismuth (Bi) elements were the predominant elements present in the prepared samples. The SEM result displaced surface irregularities due to a special bonding matrix between PVA and Bi₂O₃. Mass attenuation coefficient (MAC), effective atomic number (Zeff), Half value layer (HVL), Mean free path (MFP), Fast neutron removal cross-section (R), Total Mass Stopping Power (TSP), and photon Range (R) of the prepared polymer composites (PV-1Bi and PV-2Bi) were evaluated with XCOM and PHITS computer programs. Results showed that the MAC of the prepared polymer samples was significantly higher than some recently developed composites at 0.662MeV and 1.25MeV gamma energy. Therefore, polyvinyl alcohol (PVA) polymer doped with Bi₂O₃ should be deployed in medical apron design and shielding special electronic installations where flexibility and high adhesion ability are crucial.

Keywords: polyvinyl alcohol (PVA);, polymer composite, gamma-rays, charged particles

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940 Early-Age Cracking of Low Carbon Concrete Incorporating Ferronickel Slag as Supplementary Cementitious Material

Authors: Mohammad Khan, Arnaud Castel

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Concrete viscoelastic properties such as shrinkage, creep, and associated relaxation are important in assessing the risk of cracking during the first few days after placement. This paper investigates the early-age mechanical and viscoelastic properties, restrained shrinkage-induced cracking and time to cracking of concrete incorporating ferronickel slag (FNS) as supplementary cementitious material. Compressive strength, indirect tensile strength and elastic modulus were measured. Tensile creep and drying shrinkage was measured on dog-bone shaped specimens. Restrained shrinkage induced stresses and concrete cracking age were assessed by using the ring test. Results revealed that early-age strength development of FNS blended concrete is lower than that of the corresponding ordinary Portland cement (OPC) concrete. FNS blended concrete showed significantly higher tensile creep. The risk of early-age cracking for the restrained specimens depends on the development of concrete tensile stress considering both restrained shrinkage and tensile creep and the development of the tensile strength. FNS blended concrete showed only 20% reduction in time to cracking compared to reference OPC concrete, and this reduction is significantly lower compared to fly ash and ground granulated blast furnace slag blended concretes at similar replacement level.

Keywords: ferronickel slag, restraint shrinkage, tensile creep, time to cracking

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939 Amphibians and Water Quality: An Assessment of Diversity and Physico-Chemical Parameters of Habitats for Amphibians in Sindh, Pakistan

Authors: Kalsoom Shaikh, Saima Memon, Riffat Sultana

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Water pollution affects amphibians because they are intimately water dependent. The permeable skin makes amphibians very sensitive to the physico-chemical parameters of their aquatic environment. They spawn in water bodies where quality of water can affect the growth, development, and survival of their eggs which may die even before hatching into larvae or developing into adults due to water contamination. Considering the importance of amphibians in agriculture, food web, ecosystem and pharmaceutics as well as adverse impact of environmental degradation on them, present study was proposed to comprehensively determine the status of their diversity and habitats in Sindh province of Pakistan so as to execute monitoring for their conservation in future. Physico-chemical parameters including pH, EC (electric conductivity), TDS (total dissolved solids), T-Hard (total hardness), T-Alk (total alkalinity), Cl (chloride), CO₂ (carbon dioxide), SO₄ (sulphate), PO₄ (phosphate), NO₂ (nitrite) and NO₃ (nitrate) were analyzed from amphibian habitats using instruments and methodology of analytical grade. The results of present study after being compared with scientific data provided by different researchers and EPA (environmental protection agency), it was concluded that amphibian habitats consisted of high values of analyzed parameters except pH and CO₂. Entire study area required an urgent implementation of conservation actions for saving amphibians.

Keywords: amphibians, diversity, habitats, physico-chemical parameters, water quality, Pakistan, Sindh Province

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938 Roof Integrated Photo Voltaic with Air Collection on Glasgow School of Art Campus Building: A Feasibility Study

Authors: Rosalie Menon, Angela Reid

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Building integrated photovoltaic systems with air collectors (hybrid PV-T) have proved successful however there are few examples of their application in the UK. The opportunity to pull heat from behind the PV system to contribute to a building’s heating system is an efficient use of waste energy and its potential to improve the performance of the PV array is well documented. As part of Glasgow School of Art’s estate expansion, the purchase and redevelopment of an existing 1950’s college building was used as a testing vehicle for the hybrid PV-T system as an integrated element of the upper floor and roof. The primary objective of the feasibility study was to determine if hybrid PV-T was technically and financially suitable for the refurbished building. The key consideration was whether the heat recovered from the PV panels (to increase the electrical efficiency) can be usefully deployed as a heat source within the building. Dynamic thermal modelling (IES) and RetScreen Software were used to carry out the feasibility study not only to simulate overshadowing and optimise the PV-T locations but also to predict the atrium temperature profile; predict the air load for the proposed new 4 No. roof mounted air handling units and to predict the dynamic electrical efficiency of the PV element. The feasibility study demonstrates that there is an energy reduction and carbon saving to be achieved with each hybrid PV-T option however the systems are subject to lengthy payback periods and highlights the need for enhanced government subsidy schemes to reward innovation with this technology in the UK.

Keywords: building integrated, photovoltatic thermal, pre-heat air, ventilation

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937 Structural Assessment of Low-Rise Reinforced Concrete Frames under Tsunami Loads

Authors: Hussain Jiffry, Kypros Pilakoutas, Reyes Garcia Lopez

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This study examines the effect of tsunami loads on reinforced concrete (RC) frame buildings analytically. The impact of tsunami wave loads and waterborne objects are analyzed using a typical substandard full-scale two-story RC frame building tested as part of the EU-funded Ecoleader project. The building was subjected to shake table tests in bare condition and subsequently strengthened using Carbon Fiber Reinforced Polymers (CFRP) composites and retested. Numerical models of the building in both bare and CFRP-strengthened conditions are calibrated in DRAIN-3DX software to match the test results. To investigate the response of wave loads and impact forces, the numerical models are subjected to nonlinear dynamic analyses using force-time history input records. The analytical results are compared in terms of displacements at the floors and the 'impact point' of a boat. The results show that the roof displacement of the CFRP-strengthened building reduced by 63% when compared to the bare building. The results also indicate that strengthening only the mid-height of the impact column using CFRP is more efficient at reducing damage when compared to strengthening other parts of the column. Alternative solutions to mitigate damage due to tsunami loads are suggested.

Keywords: tsunami loads, hydrodynamic load, impact load, waterborne objects, RC buildings

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936 Morphological Characterization and Gas Permeation of Commercially Available Alumina Membrane

Authors: Ifeyinwa Orakwe, Ngozi Nwogu, Edward Gobina

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This work presents experimental results relating to the structural characterization of a commercially available alumina membrane. A γ-alumina mesoporous tubular membrane has been used. Nitrogen adsorption-desorption, scanning electron microscopy and gas permeability test has been carried out on the alumina membrane to characterize its structural features. Scanning electron microscopy (SEM) was used to determine the pore size distribution of the membrane. Pore size, specific surface area and pore size distribution were also determined with the use of the Nitrogen adsorption-desorption instrument. Gas permeation tests were carried out on the membrane using a variety of single and mixed gases. The permeabilities at different pressure between 0.05-1 bar and temperature range of 25-200oC were used for the single and mixed gases: nitrogen (N2), helium (He), oxygen (O2), carbon dioxide (CO2), 14%CO₂/N₂, 60%CO₂/N₂, 30%CO₂/CH4 and 21%O₂/N₂. Plots of flow rate verses pressure were obtained. Results got showed the effect of temperature on the permeation rate of the various gases. At 0.5 bar for example, the flow rate for N2 was relatively constant before decreasing with an increase in temperature, while for O2, it continuously decreased with an increase in temperature. In the case of 30%CO₂/CH4 and 14%CO₂/N₂, the flow rate showed an increase then a decrease with increase in temperature. The effect of temperature on the membrane performance of the various gases is presented and the influence of the trans membrane pressure drop will be discussed in this paper.

Keywords: alumina membrane, Nitrogen adsorption-desorption, scanning electron microscopy, gas permeation, temperature

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935 A Review of Sustainable Energy-Saving Solutions in Active and Passive Solar Systems of Zero Energy Buildings Based on the Internet of Things

Authors: Hanieh Sadat Jannesari, Hoori Jannesar, Alireza Hajian HosseinAbadi

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In general, buildings are responsible for a considerable share of consumed energy and carbon emissions worldwide and play a significant role in formulating sustainable development strategies. Therefore, a lot of effort is put into the design and construction of zero-energy buildings (ZEBs) to help eliminate the problems associated with the reduction of energy resources and environmental degradation. Two strategies are significant in designing ZEBs: minimizing the need for energy utilization in buildings (particularly for cooling and heating) through highly energy-efficient designs and using renewable energies and other technologies to meet the remaining energy needs. This paper reviews the works related to these two strategies concerning sustainable energy-saving solutions using renewable energy technologies and the Internet of Things in ZEBs. Drawing on the theories and recently implemented projects of energy engineers in ZEBs, we have reported the required technologies within the framework of this paper’s objectives. Overall, solutions based on renewable and sustainable technologies such as photovoltaic (PV) modules, thermal collectors, Phase Change Material (PCM) techniques, etc., are used in active and passive systems designed for various applications in such buildings as cooling, heating, lighting, cooking, etc. The results obtained from examining these projects show that it is possible to minimize the amount of energy required to be produced for and consumed by these buildings.

Keywords: active and passive renewable energy systems, internet of things, storage, zero energy buildings

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934 Development of Membrane Reactor for Auto Thermal Reforming of Dimethyl Ether for Hydrogen Production

Authors: Tie-Qing Zhang, Seunghun Jung, Young-Bae Kim

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This research is devoted to developing a membrane reactor to flexibly meet the hydrogen demand of onboard fuel cells, which is an important part of green energy development. Among many renewable chemical products, dimethyl ether (DME) has the advantages of low reaction temperature (400 °C in this study), high hydrogen atom content, low toxicity, and easy preparation. Autothermal reforming, on the other hand, has a high hydrogen recovery rate and exhibits thermal neutrality during the reaction process, so the additional heat source in the hydrogen production process can be omitted. Therefore, the DME auto thermal reforming process was adopted in this study. To control the temperature of the reaction catalyst bed and hydrogen production rate, a Model Predictive Control (MPC) scheme was designed. Taking the above two variables as the control objectives, stable operation of the reformer can be achieved by controlling the flow rates of DME, steam, and high-purity air in real-time. To prevent catalyst poisoning in the fuel cell, the hydrogen needs to be purified to reduce the carbon monoxide content to below 50 ppm. Therefore, a Pd-Ag hydrogen semi-permeable membrane with a thickness of 3-5 μm was inserted into the auto thermal reactor, and the permeation efficiency of hydrogen was improved by steam purging on the permeation side. Finally, hydrogen with a purity of 99.99 was obtained.

Keywords: hydrogen production, auto thermal reforming, membrane, fuel cell

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933 Urban Forest Innovation Lab as a Driver to Boost Forest Bioeconomy

Authors: Carmen Avilés Palacios, Camilo Muñoz Arenas, Joaquín García Alfonso, Jesús González Arteaga, Alberto Alcalde Calonge

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There is a need for review of the consumption and production models of industrialized states in accordance with the Paris Agreement and the Sustainable Development Goals (1) (OECD, 2016). This constitutes the basis of the bioeconomy (2) that is focused on striking a balance between economic development, social development and environmental protection. Bioeconomy promotes the adequate use and consumption of renewable natural resources (3) and involves developing new products and services adapted to the principles of circular economy: more sustainable (reusable, biodegradable, renewable and recyclable) and with a lower carbon footprint (4). In this context, Urban Forest Innovation Lab (UFIL) grows, an Urban Laboratory for experimentation focused on promoting entrepreneurship in forest bioeconomy (www.uiacuenca.es). UFIL generates local wellness taking sustainable advantage of an endogenous asset, forests. UFIL boosts forest bioeconomy opening its doors of knowledge to pioneers in this field, giving the opportunity to be an active part of a change in the way of understanding the exploitation of natural resources, discovering business, learning strategies and techniques and incubating business ideas So far now, 100 entrepreneurs are incubating their nearly 30 new business plans. UFIL has promoted an ecosystem to connect the rural-urban world that promotes sustainable rural development around the forest.

Keywords: bioeconomy, forestry, innovation, entrepreneurship

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932 Bringing German History to Tourists

Authors: Gudrun Görlitz, Christian Schölzel, Alexander Vollmar

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Sites of Jewish Life in Berlin 1933-1945. Between Persecution and Self-assertion” was realized in a project funded by the European Regional Development Fund. A smartphone app, and a associated web site enable tourists and other participants of this educational offer to learn in a serious way more about the life of Jews in the German capital during the Nazi era. Texts, photos, video and audio recordings communicate the historical content. Interactive maps (both current and historical) make it possible to use predefined or self combined routes. One of the manifold challenges was to create a broad ranged guide, in which all detailed information are well linked with each other. This enables heterogeneous groups of potential users to find a wide range of specific information, corresponding with their particular wishes and interests. The multitude of potential ways to navigate through the diversified information causes (hopefully) the users to utilize app and web site for a second or third time and with a continued interest. Therefore 90 locations, a lot of them situated in Berlin’s city centre, have been chosen. For all of them text-, picture and/or audio/video material gives extensive information. Suggested combinations of several of these “site stories” are leading to the offer of detailed excursion routes. Events and biographies are also presented. A few of the implemented biographies are especially enriched with source material concerning the aspect of (forced) migration of these persons during the Nazi time. All this was done in a close and fruitful interdisciplinary cooperation of computer scientists and historians. The suggested conference paper aims to show the challenges shaping complex source material for practical use by different user-groups in a proper technical and didactic way. Based on the historical research in archives, museums, libraries and digital resources the quantitative dimension of the project can be sized as follows: The paper focuses on the following historiographical and technical aspects: - Shaping the text material didactically for the use in new media, especially a Smartphone-App running on differing platforms; - Geo-referencing of the sites on historical and current map material; - Overlay of old and new maps to present and find the sites; - Using Augmented Reality technologies to re-visualize destroyed buildings; - Visualization of black-/white-picture-material; - Presentation of historical footage and the resulting problems to need too much storage space; - Financial and juridical aspects in gaining copyrights to present archival material.

Keywords: smartphone app, history, tourists, German

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931 Visual Representation and the De-Racialization of Public Spaces

Authors: Donna Banks

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In 1998 Winston James called for more research on the Caribbean diaspora and this ethnographic study, incorporating participant observation, interviews, and archival research, adds to the scholarship in this area. The research is grounded in the discipline of cultural studies but is cross-disciplinary in nature, engaging anthropology, psychology, and urban planning. This paper centers on community murals and their contribution to a more culturally diverse and representative community. While many museums are in the process of reassessing their collection, acquiring works, and developing programming to be more inclusive, and public art programs are investing millions of dollars in trying to fashion an identity in which all residents can feel included, local artists in neighborhoods in many countries have been using community murals to tell their stories. Community murals serve a historical, political, and social purpose and are an instrumental strategy in creative placemaking projects. Community murals add to the livability of an area. Even though official measurements of livability do not include race, ethnicity, and gender - which are egregious omissions - murals are a way to integrate historically underrepresented people into the wider history of a country. This paper draws attention to a creative placemaking project in the port city of Bristol, England. A city, like many others, with a history of spacializing race and racializing space. For this reason, Bristol’s Seven Saints of St. Pauls® Art & Heritage Trail, which memorializes seven Caribbean-born social and political change agents, is examined. The Seven Saints of St. Pauls® Art & Heritage Trail is crucial to the city, as well as the country, in its contribution to the de-racialization of public spaces. Within British art history, with few exceptions, portraits of non-White people who are not depicted in a subordinate role have been absent. The artist of the mural project, Michelle Curtis, has changed this long-lasting racist and hegemonic narrative. By creating seven large-scale portraits of individuals not typically represented visually, the artist has added them into Britain’s story. In these murals, however, we see more than just the likeness of a person; we are presented with a visual commentary that reflects each Saint’s hybrid identity of being both Black Caribbean and British, as well as their social and political involvement. Additionally, because the mural project is part of a heritage trail, the murals' are therapeutic and contribute to improving the well-being of residents and strengthening their sense of belonging.

Keywords: belonging, murals, placemaking, representation

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930 A Study of Heavy Hydrocarbons Upgrading by Microwave Pyrolysis

Authors: Thanida Sritangthong, Suksun Amornraksa

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By-product upgrading is crucial in hydrocarbon industries as it can increase overall profit margin of the business. Microwave-assisted pyrolysis is relatively new technique which induces heat directly to raw materials. This results in a more energy saving and more energy-efficient process. It is also a promising method to enhance and accelerate chemical reactions, thus reducing the pyrolysis reaction time and increasing the quality of value-added products from different kinds of feedstocks. In this study, upgrading opportunity of fuel oil by-product from an olefins plant is investigated by means of microwave pyrolysis. The experiment was conducted in a lab-scale quartz reactor placed inside a 1,100 watts household microwave oven. Operating temperature was varied from 500 to 900C to observe the consequence on the quality of pyrolysis products. Several microwave receptors i.e. activated carbon, silicon carbide (SiC) and copper oxide (CuO) were used as a material to enhance the heating and reaction in the reactor. The effect of residence time was determined by adjusting flow rate of N2 carrier gas. The chemical composition and product yield were analyzed by using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The results showed that hydrogen, methane, ethylene, and ethane were obtained as the main gaseous products from all operating temperatures while the main liquid products were alkane, cycloalkane and polycyclic aromatic groups. The results indicated that microwave pyrolysis has a potential to upgrade low value hydrocarbons to high value products.

Keywords: fuel oil, heavy hydrocarbons, microwave pyrolysis, pyrolysis

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929 Enhancing Fracture Toughness of CF/PAEK Laminates for High-Velocity Impact Applications: An Experimental Investigation

Authors: Johannes Keil, Eric Mischorr, Veit Würfel, Jan Condé-Wolter, Alexander Liebsch, Maik Gude

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In the aviation sector wastewater pipes are subjected to many different mechanical and medial loads. Worst-case scenarios include high-velocity impacts resulting from the introduction of foreign objects into the system. The industry is seeking to reduce the weight of these pipes, which are currently manufactured from titanium. A promising alternative is the use of fiber-reinforced polymers (FRP), specifically carbon fiber (CF) reinforced polyaryletherketone (PAEK) laminates. This study employs an experimental methodology to investigate the impact resistance of CF/PAEK laminates, with a particular focus on three configurations: crimp, non-crimp, and interleaved matrix rich films in cross-ply laminates. High-velocity impacts were performed using a gas gun resulting in three-dimensional damage patterns. Afterwards the damage behavior was qualitatively and quantitatively analyzed using ultrasonic scans and computed tomography (CT). Samples with an interleaved matrix-rich film led to a reduction of the damage area by around 40% compared to the non-interleaved, non-crimp samples, while the crimp architecture resulted in a reduction of more than 60%. Therefore, these findings contribute to understanding the influence of laminate architecture on impact resistance, paving the way for more efficient materials in aviation applications.

Keywords: fracture toughness, high-velocity-impact, textile architecture, thermoplastic composites

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928 A Finite Element Model to Study the Behaviour of Corroded Reinforced Concrete Beams Repaired with near Surface Mounted Technique

Authors: B. Almassri, F. Almahmoud, R. Francois

Abstract:

Near surface mounted reinforcement (NSM) technique is one of the promising techniques used nowadays to strengthen reinforced concrete (RC) structures. In the NSM technique, the Carbon Fibre Reinforced Polymer (CFRP) rods are placed inside pre-cut grooves and are bonded to the concrete with epoxy adhesive. This paper studies the non-classical mode of failure ‘the separation of concrete cover’ according to experimental and numerical FE modelling results. Experimental results and numerical modelling results of a 3D finite element (FE) model using the commercial software Abaqus and 2D FE model FEMIX were obtained on two beams, one corroded (25 years of corrosion procedure) and one control (A1CL3-R and A1T-R) were each repaired in bending using NSM CFRP rod and were then tested up to failure. The results showed that the NSM technique increased the overall capacity of control and corroded beams despite a non-classical mode of failure with separation of the concrete cover occurring in the corroded beam due to damage induced by corrosion. Another FE model used external steel stirrups around the repaired corroded beam A1CL3-R which failed with the separation of concrete cover, this model showed a change in the mode of failure form a non-classical mode of failure by the separation of concrete cover to the same mode of failure of the repaired control beam by the crushing of compressed concrete.

Keywords: corrosion, repair, Reinforced Concrete, FEM, CFRP, FEMIX

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927 Utilizing Artificial Intelligence to Predict Post Operative Atrial Fibrillation in Non-Cardiac Transplant

Authors: Alexander Heckman, Rohan Goswami, Zachi Attia, Paul Friedman, Peter Noseworthy, Demilade Adedinsewo, Pablo Moreno-Franco, Rickey Carter, Tathagat Narula

Abstract:

Background: Postoperative atrial fibrillation (POAF) is associated with adverse health consequences, higher costs, and longer hospital stays. Utilizing existing predictive models that rely on clinical variables and circulating biomarkers, multiple societies have published recommendations on the treatment and prevention of POAF. Although reasonably practical, there is room for improvement and automation to help individualize treatment strategies and reduce associated complications. Methods and Results: In this retrospective cohort study of solid organ transplant recipients, we evaluated the diagnostic utility of a previously developed AI-based ECG prediction for silent AF on the development of POAF within 30 days of transplant. A total of 2261 non-cardiac transplant patients without a preexisting diagnosis of AF were found to have a 5.8% (133/2261) incidence of POAF. While there were no apparent sex differences in POAF incidence (5.8% males vs. 6.0% females, p=.80), there were differences by race and ethnicity (p<0.001 and 0.035, respectively). The incidence in white transplanted patients was 7.2% (117/1628), whereas the incidence in black patients was 1.4% (6/430). Lung transplant recipients had the highest incidence of postoperative AF (17.4%, 37/213), followed by liver (5.6%, 56/1002) and kidney (3.6%, 32/895) recipients. The AUROC in the sample was 0.62 (95% CI: 0.58-0.67). The relatively low discrimination may result from undiagnosed AF in the sample. In particular, 1,177 patients had at least 1 AI-ECG screen for AF pre-transplant above .10, a value slightly higher than the published threshold of 0.08. The incidence of POAF in the 1104 patients without an elevated prediction pre-transplant was lower (3.7% vs. 8.0%; p<0.001). While this supported the hypothesis that potentially undiagnosed AF may have contributed to the diagnosis of POAF, the utility of the existing AI-ECG screening algorithm remained modest. When the prediction for POAF was made using the first postoperative ECG in the sample without an elevated screen pre-transplant (n=1084 on account of n=20 missing postoperative ECG), the AUROC was 0.66 (95% CI: 0.57-0.75). While this discrimination is relatively low, at a threshold of 0.08, the AI-ECG algorithm had a 98% (95% CI: 97 – 99%) negative predictive value at a sensitivity of 66% (95% CI: 49-80%). Conclusions: This study's principal finding is that the incidence of POAF is rare, and a considerable fraction of the POAF cases may be latent and undiagnosed. The high negative predictive value of AI-ECG screening suggests utility for prioritizing monitoring and evaluation on transplant patients with a positive AI-ECG screening. Further development and refinement of a post-transplant-specific algorithm may be warranted further to enhance the diagnostic yield of the ECG-based screening.

Keywords: artificial intelligence, atrial fibrillation, cardiology, transplant, medicine, ECG, machine learning

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926 Demetallization of Crude Oil: Comparative Analysis of Deasphalting and Electrochemical Removal Methods of Ni and V

Authors: Nurlan Akhmetov, Abilmansur Yeshmuratov, Aliya Kurbanova, Gulnar Sugurbekova, Murat Baisariyev

Abstract:

Extraction of the vanadium and nickel compounds is complex due to the high stability of porphyrin, nickel is catalytic poison which deactivates catalysis during the catalytic cracking of the oil, while vanadyl is abrasive and valuable metal. Thus, high concentration of the Ni and V in the crude oil makes their removal relevant. Two methods of the demetallization of crude oil were tested, therefore, the present research is conducted for comparative analysis of the deasphalting with organic solvents (cyclohexane, carbon tetrachloride, chloroform) and electrochemical method. Percentage of Ni extraction reached maximum of approximately 55% by using the electrochemical method in electrolysis cell, which was developed for this research and consists of three sections: oil and protonating agent (EtOH) solution between two conducting membranes which divides it from two capsules of 10% sulfuric acid and two graphite electrodes which cover all three parts in electrical circuit. Ions of metals pass through membranes and remain in acid solutions. The best result was obtained in 60 minutes with ethanol to oil ratio 25% to 75% respectively, current fits in to the range from 0.3A to 0.4A, voltage changed from 12.8V to 17.3V. Maximum efficiency of deasphalting, with cyclohexane as the solvent, in Soxhlet extractor was 66.4% for Ni and 51.2% for V. Thus, applying the voltammetry, ICP MS (Inductively coupled plasma mass spectrometry) and AAS (atomic absorption spectroscopy), these mentioned types of metal extraction methods were compared in this paper.

Keywords: electrochemistry, deasphalting of crude oil, demetallization of crude oil, petrolium engineering

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925 In situ High Temperature Characterization of Diamond-Like Carbon Films

Authors: M. Rouhani, F. C. N. Hong, Y. R. Jeng

Abstract:

The tribological performance of DLC films is limited by graphitization at elevated temperatures. Despite of numerous studies on the thermal stability of DLC films, a comprehensive in-situ characterization at elevated temperature is still lacking. In this study, DLC films were deposited using filtered cathodic arc vacuum method. Thermal stability of the films was characterized in-situally using a synchronized technique integrating Raman spectroscopy and depth-sensing measurements. Tests were performed in a high temperature chamber coupled with feedback control to make it possible to study the temperature effects in the range of 21 – 450 ̊C. Co-located SPM and Raman microscopy maps at different temperature over a specific area on the surface of the film were prepared. The results show that the thermal stability of the DLC films depends on their sp3 content. Films with lower sp3 content endure graphitization during the temperature-course used in this study. The graphitization is accompanied with significant changes in surface roughness and Raman spectrum of the film. Surface roughness of the films start to change even before graphitization transformation could be detected using Raman spectroscopy. Depth-sensing tests (nanoindentation, nano-scratch and wear) endorse the surface roughness change seen before graphitization occurrence. This in-situ study showed that the surface of the films is more sensitive to temperature rise compared to the bulk. We presume the changes observed in films hardness, surface roughness and scratch resistance with temperature rise, before graphitization occurrence, is due to surface relaxation.

Keywords: DLC film, nanoindentation, Raman spectroscopy, thermal stability

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924 Conservation of Ibis Statue Made of Composite Materials Dating to 3RD Intermediate Period - Late Period

Authors: Badawi Mahmoud, Eid Mohamed, Salih Hytham, Tahoun Mamdouh

Abstract:

Cultural properties made of types of materials; we can classify them broadly into three categories. There are organic cultural properties which have their origin in the animal and plant kingdoms. There are the inorganic cultural properties made of metal or stone. Then there are those made of both organic and inorganic materials such as metal with wood. Most cultural properties are made from several materials rather than from one single material. Cultural properties reveal a lot of information about the past and often have great artistic value. It is important to extend the life of cultural properties and preserve themif possible, that is intended to preserve them for future generations. The study of metallic relics usually includes examining the techniques used to make them and the extent to which they have corroded. The conservation science of archaeological artifacts demands an accurate grasp of the interior of the article, which cannot be seen. This is essential to elucidate the method of manufacture and provides information that is important for cleaning, restoration, and other processes of conservation. Conservation treatment does not ensure the prevention of further degradation of the archaeological artifact. Instead, it is an attempt to inhibit further degradation as much as possible. Ancient metallic artifacts are made of many materials. Some are made of a single metal, such as iron, copper, or bronze. There are also composite relics made of several metals. Almost all metals (except gold) corrode while they rest underground. Corrosion is caused by the interaction of oxygen, water, and various ions. Chloride ions play a major role in the advance of corrosion. Excavated metallic relics are usually scientifically examined as to their structure and materials and treated for preservation before being displayed for exhibition or stored in a storehouse. Bird statue hermit body is made of wood and legs and beak bronze, the object broken separated to three parts. This statue came to Grand Egyptian Museum – Conservation Centre (GEM-CC) Inorganic Lab. Statuette representing the god djehoty shaped of the bird (ibis) sculpture made of bronze and wood the body of statues made from wood and bronze from head and leg and founded remains of black resin maybe it found with mummy, the base installed by wooden statue of the ancient writings there dating, the archaeological unit decided the dating is 3rd intermediate period - late period. This study aims to do conservation process for this statue, attempt to inhibit further degradation as much as possible and fill fractures and cracks in the wooden part.

Keywords: inorganic materials, metal, wood, corrosion, ibis

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923 Green Hydrogen: Exploring Economic Viability and Alluring Business Scenarios

Authors: S. Sakthivel

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Currently, the global economy is based on the hydrocarbon economy, which is referencing the global hydrocarbon industry. Problems of using these fossil fuels (like oil, NG, coal) are emitting greenhouse gases (GHGs) and price fluctuation, supply/distribution, etc. These challenges can be overcome by using clean energy as hydrogen. The hydrogen economy is the use of hydrogen as a low carbon fuel, particularly for hydrogen vehicles, alternative industrial feedstock, power generation, and energy storage, etc. Engineering consulting firms have a significant role in this ambition and green hydrogen value chain (i.e., integration of renewables, production, storage, and distribution to end-users). Typically, the cost of green hydrogen is a function of the price of electricity needed, the cost of the electrolyser, and the operating cost to run the system. This article focuses on economic viability and explores the alluring business scenarios globally. Break-even analysis was carried out for green hydrogen production and in order to evaluate and compare the impact of the electricity price on the production costs of green hydrogen and relate it to fossil fuel-based brown/grey/blue hydrogen costs. It indicates that the cost of green hydrogen production will fall drastically due to the declining costs of renewable electricity prices and along with the improvement and scaling up of electrolyser manufacturing. For instance, in a scenario where electricity prices are below US$ 40/MWh, green hydrogen cost is expected to reach cost competitiveness.

Keywords: green hydrogen, cost analysis, break-even analysis, renewables, electrolyzer

Procedia PDF Downloads 134
922 Tool Wear of Aluminum/Chromium/Tungsten Based Coated Cemented Carbide Tools in Cutting Sintered Steel

Authors: Tadahiro Wada, Hiroyuki Hanyu

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In this study, to clarify the effectiveness of an aluminum/chromium/tungsten-based-coated tool for cutting sintered steel, tool wear was experimentally investigated. The sintered steel was turned with the (Al60,Cr25,W15)N-, (Al60,Cr25,W15)(C,N)- and (Al64,Cr28,W8)(C,N)-coated cemented carbide tools according to the physical vapor deposition (PVD) method. Moreover, the tool wear of the aluminum/chromium/tungsten-based-coated item was compared with that of the (Al,Cr)N coated tool. Furthermore, to clarify the tool wear mechanism of the aluminum/chromium/tungsten-coating film for cutting sintered steel, Scanning Electron Microscope observation and Energy Dispersive x-ray Spectroscopy mapping analysis were conducted on the abraded surface. The following results were obtained: (1) The wear progress of the (Al64,Cr28,W8)(C,N)-coated tool was the slowest among that of the five coated tools. (2) Adding carbon (C) to the aluminum/chromium/tungsten-based-coating film was effective for improving the wear-resistance. (3) The main wear mechanism of the (Al60,Cr25,W15)N-, the (Al60,Cr25,W15)(C,N)- and the (Al64,Cr28,W8)(C,N)-coating films was abrasive wear.

Keywords: cutting, physical vapor deposition coating method, tool wear, tool wear mechanism, (Al, Cr, W)N-coating film, (Al, Cr, W)(C, N)-coating film, sintered steel

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921 Upconversion Nanoparticles for Imaging and Controlled Photothermal Release of Anticancer Drug in Breast Cancer

Authors: Rishav Shrestha, Yong Zhang

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The Anti-Stoke upconversion process has been used extensively for bioimaging and is recently being used for photoactivated therapy in cancer utilizing upconversion nanoparticles (UCNs). The UCNs have an excitation band at 980nm; 980nm laser excitation used to produce UV/Visible emissions also produce a heating effect. Light-to-heat conversion has been observed in nanoparticles(NPs) doped with neodymium(Nd) or ytterbium(Yb)/erbium(Er) ions. Despite laser-induced heating in Rare-earth doped NPs being proven to be a relatively efficient process, only few attempts to use them as photothermal agents in biosystems have been made up to now. Gold nanoparticles and carbon nanotubes are the most researched and developed for photothermal applications. Both have large heating efficiency and outstanding biocompatibility. However, they show weak fluorescence which makes them harder to track in vivo. In that regard, UCNs are attractive due to their excellent optical features in addition to their light-to-heat conversion and excitation by NIR, for imaging and spatiotemporally releasing drugs. In this work, we have utilized a simple method to coat Nd doped UCNs with thermoresponsive polymer PNIPAM on which 4-Hydroxytamoxifen (4-OH-T) is loaded. Such UCNs demonstrate a high loading efficiency and low leakage of 4-OH-T. Encouragingly, the release of 4-OH-T can be modulated by varying the power and duration of the NIR. Such UCNs were then used to demonstrate imaging and controlled photothermal release of 4-OH-T in MCF-7 breast cancer cells.

Keywords: cancer therapy, controlled release, photothermal release, upconversion nanoparticles

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920 Preparation and Characterization of Phosphate-Nickel-Titanium Composite Coating Obtained by Sol Gel Process for Corrosion Protection

Authors: Khalidou Ba, Abdelkrim Chahine, Mohamed Ebn Touhami

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A strong industrial interest is focused on the development of coatings for anticorrosion protection. In this context, phosphate composite materials are expanding strongly due to their chemical characteristics and their interesting physicochemical properties. Sol-gel coatings offer high homogeneity and purity that may lead to obtain coating presenting good adhesion to metal surface. The goal behind this work is to develop efficient coatings for corrosion protection of steel to extend its life. In this context, a sol gel process allowing to obtain thin film coatings on carbon steel with high resistance to corrosion has been developed. The optimization of several experimental parameters such as the hydrolysis time, the temperature, the coating technique, the molar ratio between precursors, the number of layers and the drying mode has been realized in order to obtain a coating showing the best anti-corrosion properties. The effect of these parameters on the microstructure and anticorrosion performance of the films sol gel coating has been investigated using different characterization methods (FTIR, XRD, Raman, XPS, SEM, Profilometer, Salt Spray Test, etc.). An optimized coating presenting good adhesion and very stable anticorrosion properties in salt spray test, which consists of a corrosive attack accelerated by an artificial salt spray consisting of a solution of 5% NaCl, pH neutral, under precise conditions of temperature (35 °C) and pressure has been obtained.

Keywords: sol gel, coating, corrosion, XPS

Procedia PDF Downloads 124
919 Computational Modeling of Thermal Comfort and CO2 Distribution in Common Room-Lecture Room by Using Hybrid Air Ventilation System, Thermoelectric-PV-Silica Gel under IAQ Standard

Authors: Jirod Chaisan, Somchai Maneewan, Chantana Punlek, Ninnart Rachapradit, Surapong Chirarattananon, Pattana Rakkwamsuk

Abstract:

In this paper, simulation modeling of heat transfer, air flow and distribution emitted from CO2 was performed in a regenerated air. The study room was divided in 3 types: common room, small lecture room and large lecture room under evaluated condition in two case: released and unreleased CO2 including of used hybrid air ventilation system for regenerated air under Thailand climate conditions. The carbon dioxide was located on the center of the room and released rate approximately 900-1200 ppm corresponded with indoor air quality standard (IAQs). The indoor air in the thermal comfort zone was calculated and simulated with the numerical method that using real data from the handbook guideline. The results of the study showed that in the case of hybrid air ventilation system explained thermal and CO2 distribution due to the system was adapted significantly in the comfort zone. The results showed that when CO2 released on the center of the other room, the CO2 high concentration in comfort zone so used hybrid air ventilation that decreased CO2 with regeneration air including of reduced temperature indoor. However, the study is simulation modeling and guideline only so the future should be the experiment of hybrid air ventilation system for evaluated comparison of the systems.

Keywords: air ventilation, indoor air quality, thermal comfort, thermoelectric, photovoltaic, dehumidify

Procedia PDF Downloads 479