Search results for: water flow velocity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13025

Search results for: water flow velocity

3515 Protected Cultivation of Horticultural Crops: Increases Productivity per Unit of Area and Time

Authors: Deepak Loura

Abstract:

The most contemporary method of producing horticulture crops both qualitatively and quantitatively is protected cultivation, or greenhouse cultivation, which has gained widespread acceptance in recent decades. Protected farming, commonly referred to as controlled environment agriculture (CEA), is extremely productive, land- and water-wise, as well as environmentally friendly. The technology entails growing horticulture crops in a controlled environment where variables such as temperature, humidity, light, soil, water, fertilizer, etc. are adjusted to achieve optimal output and enable a consistent supply of them even during the off-season. Over the past ten years, protected cultivation of high-value crops and cut flowers has demonstrated remarkable potential. More and more agricultural and horticultural crop production systems are moving to protected environments as a result of the growing demand for high-quality products by global markets. By covering the crop, it is possible to control the macro- and microenvironments, enhancing plant performance and allowing for longer production times, earlier harvests, and higher yields of higher quality. These shielding features alter the environment of the plant while also offering protection from wind, rain, and insects. Protected farming opens up hitherto unexplored opportunities in agriculture as the liberalised economy and improved agricultural technologies advance. Typically, the revenues from fruit, vegetable, and flower crops are 4 to 8 times higher than those from other crops. If any of these high-value crops are cultivated in protected environments like greenhouses, net houses, tunnels, etc., this profit can be multiplied. Vegetable and cut flower post-harvest losses are extremely high (20–0%), however sheltered growing techniques and year-round cropping can greatly minimize post-harvest losses and enhance yield by 5–10 times. Seasonality and weather have a big impact on the production of vegetables and flowers. The variety of their products results in significant price and quality changes for vegetables. For the application of current technology in crop production, achieving a balance between year-round availability of vegetables and flowers with minimal environmental impact and remaining competitive is a significant problem. The future of agriculture will be protected since population growth is reducing the amount of land that may be held. Protected agriculture is a particularly profitable endeavor for tiny landholdings. Small greenhouses, net houses, nurseries, and low tunnel greenhouses can all be built by farmers to increase their income. Protected agriculture is also aided by the rise in biotic and abiotic stress factors. As a result of the greater productivity levels, these technologies are not only opening up opportunities for producers with larger landholdings, but also for those with smaller holdings. Protected cultivation can be thought of as a kind of precise, forward-thinking, parallel agriculture that covers almost all aspects of farming and is rather subject to additional inspection for technical applicability to circumstances, farmer economics, and market economics.

Keywords: protected cultivation, horticulture, greenhouse, vegetable, controlled environment agriculture

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3514 A Structured Mechanism for Identifying Political Influencers on Social Media Platforms: Top 10 Saudi Political Twitter Users

Authors: Ahmad Alsolami, Darren Mundy, Manuel Hernandez-Perez

Abstract:

Social media networks, such as Twitter, offer the perfect opportunity to either positively or negatively affect political attitudes on large audiences. The existence of influential users who have developed a reputation for their knowledge and experience of specific topics is a major factor contributing to this impact. Therefore, knowledge of the mechanisms to identify influential users on social media is vital for understanding their effect on their audience. The concept of the influential user is related to the concept of opinion leaders' to indicate that ideas first flow from mass media to opinion leaders and then to the rest of the population. Hence, the objective of this research was to provide reliable and accurate structural mechanisms to identify influential users, which could be applied to different platforms, places, and subjects. Twitter was selected as the platform of interest, and Saudi Arabia as the context for the investigation. These were selected because Saudi Arabia has a large number of Twitter users, some of whom are considerably active in setting agendas and disseminating ideas. The study considered the scientific methods that have been used to identify public opinion leaders before, utilizing metrics software on Twitter. The key findings propose multiple novel metrics to compare Twitter influencers, including the number of followers, social authority and the use of political hashtags, and four secondary filtering measures. Thus, using ratio and percentage calculations to classify the most influential users, Twitter accounts were filtered, analyzed and included. The structured approach is used as a mechanism to explore the top ten influencers on Twitter from the political domain in Saudi Arabia.

Keywords: Twitter, influencers, structured mechanism, Saudi Arabia

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3513 Antioxidant Defence Systems, Lipid Peroxidation, and Photosynthetic Variables in Salt-Sensitive and Salt-Tolerant Soybean Genotypes in Response to Salt Stress

Authors: Faheema Khan

Abstract:

We have investigated the effects of salt stress on the stability of plant growth, water relations, photosynthetic variables, lipid peroxidation and antioxidant system in salt-tolerant (PK-327) and salt-sensitive (PK-471) soybean genotypes. Ten-day-old salt-tolerant and salt-sensitive soybean plants were subjected to 0-150 mM NaCl for 15 days. While the growth of genotype PK-327 was not affected significantly up to 75 mM NaCl treatment, the growth of the PK-471 was reduced significantly beyond 25 mM NaCl treatments. Salt stress caused severe impairments in photosynthetic variables like photosynthetic rate, chlorophyll fluorescence and chlorophyll content, being more pronounced in salt-sensitive genotype than in salt-tolerant.The activities of antioxidant enzymes (superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase) were higher in PK-327 than in PK-471 at various levels of salt treatments.It is concluded that tolerance capacity of PK-327 against salinity can be associated with the ability of this genotype in keeping an active photosynthetic system and strong antioxidant defence system.

Keywords: salt stress, soybean, antioxidant, photosynthesis

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3512 Financing Innovation: Differences across National Innovation Systems

Authors: Núria Arimany Serrat, Xavier Ferràs Hernández, Petra A. Nylund, Eric Viardot

Abstract:

Innovation is an increasingly important antecedent to firm competitiveness and growth. Successful innovation, however, requires a significant financial commitment and the means of financing accessible to the firm may affect its ability to innovate. The access to equity financing such as venture capital has been connected to innovativeness for young firms. For established enterprises, debt financing of innovation may be a more realistic option. Continuous innovation and growth would otherwise require a constant increase of equity. We, therefore, investigate the relation between debt financing and innovation for large firms and hypothesize that those firms that carry more debt will be more innovative. The need for debt financing of innovation may be reduced for very profitable firms, which can finance innovation with cash flow. We thus hypothesize a moderating effect of profitability on the relationship between debt financing and innovation. We carry out an empirical investigation using a longitudinal data set including 167 large European firms over five years, resulting in 835 firm years. We apply generalized least squares (GLS) regression with fixed firm effects to control for firm heterogeneity. The findings support our hypotheses and we conclude that access to debt finding is an important antecedent of innovation, with profitability as a moderating factor. The results do however differ across national innovation systems and we find a strong relationship for British, Dutch, French, and Italian firms but not for German and Spanish entities. We discuss differences in the national systems of innovation and financing which contextualize the variations in the findings and thus make a nuanced contribution to the research in innovation financing. The cross-country differences calls for differentiated advice to managers, institutions, and researchers depending on the national context.

Keywords: innovation, R&D, national innovation systems, financing

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3511 Chemical and Sensorial Evaluation of a Newly Developed Bean Jam

Authors: Raquel P. F. Guiné, Ana R. B. Figueiredo, Paula M. R. Correia, Fernando J. Gonçalves

Abstract:

The purpose of the present work was to develop an innovative food product with nutritional properties as well as appealing organoleptic qualities. The product, a jam, was prepared with the beans’ cooking water combined with fresh apple or carrot, without the addition of any conservatives. Three different jams were produced: bean and carrot, bean and apple and bean, apple and cinnamon. The developed products underwent a sensorial analysis that revealed that the bean, apple and cinnamon jam was globally better accepted. However, with this study, the consumers determined that the bean and carrot jam had the most attractive color and the bean and apple jam the better consistency. Additionally, it was possible to analyze the jams for their chemical components, namely fat, fiber, protein, sugars and antioxidant activity. The obtained results showed that the bean and carrot jam had the highest lipid content, while the bean, apple and cinnamon jam had the highest fiber content, when compared to the other two jams. Regarding the sugar content, both jams with apple revealed similar sugar values, which were higher than the sugar content of the bean and carrot jam. The antioxidant activity was on average 10 mg TE/g.

Keywords: Bean jam, chemical composition, sensorial analysis, product acceptability

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3510 Electromagnetic and Physicochemical Properties in the Addition of Silicon Oxide on the SSPS Renewable Films

Authors: Niloofar Alipoormazandarani

Abstract:

The rift environmental, efficiency and being environmental-friendly of these innovative food packaging in edible films made them as an alternative to synthetic packages. This issue has been widely studied in this experiment. Some of the greatest advances in food packaging industry is associated with nanotechnology. Recently, a polysaccharide extracted from the cell wall of soybean cotyledons: A soluble soybean polysaccharide (SSPS), a pectin-like structure. In this study, the addition (0%, 1%, 3%, and 5%) of nano silica dioxide (SiO2) film is examined SSPS in different features. The research aims to investigate the effect of nano-SiO2 on the physicochemical and electromagnetic properties of the SSPS films were sonicated and then heated to the melting point, besides the addition of plasticizer. After that, it has been cooled into the room temperature and were dried with Casting method. In final examinations,improvement in Moisture Content and Water Absorption was observed with a significant decrease.Also, in Color measurements there were some obvious differences. These reports indicate that the incorporation of nano-SiO2 and SSPS has the power to be extensively used in pharmaceutical and food packaging industry as well.

Keywords: SSPS, NanoSiO2, food packaging, renewable films

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3509 Breeding Biology of Priacanthus hamrur (Forsskal) off Mangalore Coast, Karnataka, India

Authors: H. N. Anjanayappa, S. Benakappa, A. T. Ramachandra Naik, P. Nayana, D. P. Rajesh

Abstract:

Fishes of the family Priacanthidae, popularly called big eye or bulls eye. Priacanthus hamrur is an important deep-water inhabitant of great commercial value. High percentage of landings of Priancanthids used as raw material for surimi, sausage and other fishery by-products. Presently, it has great demand in Singapore Thailand, Taiwan, Hong Kong and other countries. For the maturation studies, samples were collected from commercial landing centre, Mangalore. Studies on reproductive biology showed that Priacanthus hamrur spawns twice in a year, the spawning season extending from March to May and October to November. Based on the percentage occurrence of mature fishes in various size group it was inferred that male attained maturity at smaller size than female. This study will enable us to understand the spawning periodicity, cyclic morphological changes in male, female gonads and also it helps to improve stock size by enforcing fishing ban in particular season by assessing spawning periodicity.

Keywords: breeding biology, Mangalore, morphological changes, Priacanthus hamrur

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3508 Integrated Dynamic Analysis of Semi-Submersible Flap Type Concept

Authors: M. Rafiur Rahman, M. Mezbah Uddin, Mohammad Irfan Uddin, M. Moinul Islam

Abstract:

With a rapid development of offshore renewable energy industry, the research activities in regards of harnessing power from offshore wind and wave energy are increasing day by day. Integration of wind turbines and wave energy converters into one combined semi-submersible platform might be a cost-economy and beneficial option. In this paper, the coupled integrated dynamic analysis in the time domain (TD) of a simplified semi-submersible flap type concept (SFC) is accomplished via state-of-the-art numerical code referred as Simo-Riflex-Aerodyn (SRA). This concept is a combined platform consisting of a semi-submersible floater supporting a 5 MW horizontal axis wind turbine (WT) and three elliptical shaped flap type wave energy converters (WECs) on three pontoons. The main focus is to validate the numerical model of SFC with experimental results and perform the frequency domain (FD) and TD response analysis. The numerical analysis is performed using potential flow theory for hydrodynamics and blade element momentum (BEM) theory for aerodynamics. A variety of environmental conditions encompassing the functional & survival conditions for short-term sea (1-hour simulation) are tested to evaluate the sustainability of the SFC. The numerical analysis is performed in full scale. Finally, the time domain analysis of heave, pitch & surge motions is performed numerically using SRA and compared with the experimental results. Due to the simplification of the model, there are some discrepancies which are discussed in brief.

Keywords: coupled integrated dynamic analysis, SFC, time domain analysis, wave energy converters

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3507 Alumina Supported Copper-manganese Catalysts for Combustion of Exhaust Gases: Catalysts Characterization

Authors: Krasimir I. Ivanov, Elitsa N. Kolentsova, Dimitar Y. Dimitrov, Georgi V. Avdeev, Tatyana T. Tabakova

Abstract:

In recent research copper and manganese systems were found to be the most active in CO and organic compounds oxidation among the base catalysts. The mixed copper manganese oxide has been widely studied in oxidation reactions because of their higher activity at low temperatures in comparison with single oxide catalysts. The results showed that the formation of spinel CuxMn3−xO4 in the oxidized catalyst is responsible for the activity even at room temperature. That is why most of the investigations are focused on the hopcalite catalyst (CuMn2O4) as the best copper-manganese catalyst. Now it’s known that this is true only for CO oxidation, but not for mixture of CO and VOCs. The purpose of this study is to investigate the alumina supported copper-manganese catalysts with different Cu/Mn molar ratio in terms of oxidation of CO, methanol and dimethyl ether. The catalysts were prepared by impregnation of γ-Al2O3 with copper and manganese nitrates and the catalytic activity measurements were carried out in continuous flow equipment with a four-channel isothermal stainless steel reactor. Gas mixtures on the input and output of the reactor were analyzed with a gas chromatograph, equipped with FID and TCD detectors. The texture characteristics were determined by low-temperature (- 196 oС) nitrogen adsorption in a Quantachrome Instruments NOVA 1200e (USA) specific surface area&pore analyzer. Thermal, XRD and TPR analyses were performed. It was established that the active component of the mixed Cu-Mn/γ–alumina catalysts strongly depends on the Cu/Mn molar ratio. Highly active alumina supported Cu-Mn catalysts for CO, methanol and DME oxidation were synthesized. While the hopcalite is the best catalyst for CO oxidation, the best compromise for simultaneous oxidation of all components is the catalyst with Cu/Mn molar ratio 1:5.

Keywords: supported copper-manganese catalysts, CO, VOCs oxidation, combustion of exhaust gases

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3506 Structure-Activity Relationship of Gold Catalysts on Alumina Supported Cu-Ce Oxides for CO and Volatile Organic Compound Oxidation

Authors: Tatyana T. Tabakova, Elitsa N. Kolentsova, Dimitar Y. Dimitrov, Krasimir I. Ivanov, Yordanka G. Karakirova, Petya Cv. Petrova, Georgi V. Avdeev

Abstract:

The catalytic oxidation of CO and volatile organic compounds (VOCs) is considered as one of the most efficient ways to reduce harmful emissions from various chemical industries. The effectiveness of gold-based catalysts for many reactions of environmental significance was proven during the past three decades. The aim of this work was to combine the favorable features of Au and Cu-Ce mixed oxides in the design of new catalytic materials of improved efficiency and economic viability for removal of air pollutants in waste gases from formaldehyde production. Supported oxides of copper and cerium with Cu: Ce molar ratio 2:1 and 1:5 were prepared by wet impregnation of g-alumina. Gold (2 wt.%) catalysts were synthesized by a deposition-precipitation method. Catalysts characterization was carried out by texture measurements, powder X-ray diffraction, temperature programmed reduction and electron paramagnetic resonance spectroscopy. The catalytic activity in the oxidation of CO, CH3OH and (CH3)2O was measured using continuous flow equipment with fixed bed reactor. Both Cu-Ce/alumina samples demonstrated similar catalytic behavior. The addition of gold caused significant enhancement of CO and methanol oxidation activity (100 % degree of CO and CH3OH conversion at about 60 and 140 oC, respectively). The composition of Cu-Ce mixed oxides affected the performance of gold-based samples considerably. Gold catalyst on Cu-Ce/γ-Al2O3 1:5 exhibited higher activity for CO and CH3OH oxidation in comparison with Au on Cu-Ce/γ-Al2O3 2:1. The better performance of Au/Cu-Ce 1:5 was related to the availability of highly dispersed gold particles and copper oxide clusters in close contact with ceria.

Keywords: CO and VOCs oxidation, copper oxide, Ceria, gold catalysts

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3505 Effect of Anisotropy on Steady Creep in a Whisker Reinforced Functionally Graded Composite Disc

Authors: V. K. Gupta, Tejeet Singh

Abstract:

In many whisker reinforced composites, anisotropy may result due to material flow during processing operations such as forging, extrusion etc. The consequence of anisotropy, introduced during processing of disc material, has been investigated on the steady state creep deformations of the rotating disc. The disc material is assumed to undergo plastic deformations according to Hill’s anisotropic criterion. Steady state creep has been analyzed in a constant thickness rotating disc made of functionally graded 6061Al-SiCw (where the subscript ‘w’ stands for whisker) using Hill’s The content of reinforcement (SiCw) in the disc is assumed to decrease linearly from the inner to outer radius. The stresses and strain rates in the disc are estimated by solving the force equilibrium equation along with the constitutive equations describing multi-axial creep. The results obtained for anisotropic FGM disc have been compared with those estimated for isotropic FGM disc having the same average whisker content. The anisotropic constants, appearing in Hill’s yield criterion, have been obtained from the available experimental results. The results show that the presence of anisotropy reduces the tangential stress in the middle of the disc but near the inner and outer radii the tangential stress is higher when compared to isotropic disc. On the other hand, the steady state creep rates in the anisotropic disc are reduced significantly over the entire disc radius, with the maximum reduction observed at the inner radius. Further, in the presence of anisotropy the distribution of strain rate becomes relatively uniform over the entire disc, which may be responsible for reducing the extent of distortion in the disc.

Keywords: anisotropy, creep, functionally graded composite, rotating disc

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3504 Characteristics of Domestic Sewage in Small Urban Communities

Authors: Shohreh Azizi, Memory Tekere, Wag Nel

Abstract:

An evaluation of the characteristics of wastewater generated from small communities was carried out in relation to decentralized approach for domestic sewage treatment plant and design of biological nutrient removal system. The study included the survey of the waste from various individual communities such as a hotel, a residential complex, an office premise, and an educational institute. The results indicate that the concentration of organic pollutant in wastewater from the residential complex is higher than the waste from all the other communities with COD 664 mg/l, BOD 370.2 mg/l and TSS 248.8 mg/l. And the waste water from office premise indicates low organic load with COD428 mg/l, BOD 232mg/l and TSS 157mg/l. The wastewater from residential complex was studied under activated sludge process to evaluate this technology for decentralized wastewater treatment. The Activated sludge process was operated at different 12to 4 hrs hydraulic retention times and the optimum 6 hrs HRT was selected, therefore the average reduction of COD (85.92%) and BOD (91.28 %) was achieved. The issue of sludge recycling, maintenance of biomass concentration and high HRT reactor (10 L) volume are making the system non-practical for smaller communities.

Keywords: wastewater, small communities, activated sludge process, decentralized system

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3503 Cytogenetic Characterization of the VERO Cell Line Based on Comparisons with the Subline; Implication for Authorization and Quality Control of Animal Cell Lines

Authors: Fumio Kasai, Noriko Hirayama, Jorge Pereira, Azusa Ohtani, Masashi Iemura, Malcolm A. Ferguson Smith, Arihiro Kohara

Abstract:

The VERO cell line was established in 1962 from normal tissue of an African green monkey, Chlorocebus aethiops (2n=60), and has been commonly used worldwide for screening for toxins or as a cell substrate for the production of viral vaccines. The VERO genome was sequenced in 2014; however, its cytogenetic features have not been fully characterized as it contains several chromosome abnormalities and different karyotypes coexist in the cell line. In this study, the VERO cell line (JCRB0111) was compared with one of the sublines. In contrast to 59 chromosomes as the modal chromosome number in the VERO cell line, the subline had two peaks of 56 and 58 chromosomes. M-FISH analysis using human probes revealed that the VERO cell line was characterized by a translocation t(2;25) found in all metaphases, which was absent in the subline. Different abnormalities detected only in the subline show that the cell line is heterogeneous, indicating that the subline has the potential to change its genomic characteristics during cell culture. The various alterations in the two independent lineages suggest that genomic changes in both VERO cells can be accounted for by progressive rearrangements during their evolution in culture. Both t(5;X) and t(8;14) observed in all metaphases of the two cell lines might have a key role in VERO cells and could be used as genetic markers to identify VERO cells. The flow karyotype shows distinct differences from normal. Further analysis of sorted abnormal chromosomes may uncover other characteristics of VERO cells. Because of the absence of STR data, cytogenetic data are important in characterizing animal cell lines and can be an indicator of their quality control.

Keywords: VERO, cell culture passage, chromosome rearrangement, heterogeneous cells

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3502 Properties of Ground Granulated Blast Furnace Slag Based Geopolymer Concrete

Authors: Niragi Dave, Ruchika Lalit

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Concrete is one of the most widely used materials across the globe mostly second to water and generating high carbon dioxide emission during its whole manufacturing due to the presence of cement as an ingredient. Therefore it is necessary to find an alternative material to the Portland cement. This study focused on the use of Ground Granulated Blast Furnace Slag as geopolymer binder. Geopolymer concrete can be an alternative material which is produced by the chemical reaction of inorganic molecules. On the other hand, waste generating from power plants and other industries like iron and steel industries can be effectively used which has disposal problems. Therefore in this study geopolymer concrete is manufactured by 100% replacement of cement content by ground granulated blast furnace slag and a combination of sodium silicate and sodium hydroxide is used as an alkaline solution. The results have shown that the compressive strengths increased with increasing curing time and type of alkali activators. Naphthalene sulfonate-based superplasticizer performed better than other superplasticizers. All the specimens have been cast at ambient temperature.

Keywords: alkali activators, concrete, geopolymer, ground granulated blast furnace slag

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3501 Shock-Induced Densification in Glass Materials: A Non-Equilibrium Molecular Dynamics Study

Authors: Richard Renou, Laurent Soulard

Abstract:

Lasers are widely used in glass material processing, from waveguide fabrication to channel drilling. The gradual damage of glass optics under UV lasers is also an important issue to be addressed. Glass materials (including metallic glasses) can undergo a permanent densification under laser-induced shock loading. Despite increased interest on interactions between laser and glass materials, little is known about the structural mechanisms involved under shock loading. For example, the densification process in silica glasses occurs between 8 GPa and 30 GPa. Above 30 GPa, the glass material returns to the original density after relaxation. Investigating these unusual mechanisms in silica glass will provide an overall better understanding in glass behaviour. Non-Equilibrium Molecular Dynamics simulations (NEMD) were carried out in order to gain insight on the silica glass microscopic structure under shock loading. The shock was generated by the use of a piston impacting the glass material at high velocity (from 100m/s up to 2km/s). Periodic boundary conditions were used in the directions perpendicular to the shock propagation to model an infinite system. One-dimensional shock propagations were therefore studied. Simulations were performed with the STAMP code developed by the CEA. A very specific structure is observed in a silica glass. Oxygen atoms around Silicon atoms are organized in tetrahedrons. Those tetrahedrons are linked and tend to form rings inside the structure. A significant amount of empty cavities is also observed in glass materials. In order to understand how a shock loading is impacting the overall structure, the tetrahedrons, the rings and the cavities were thoroughly analysed. An elastic behaviour was observed when the shock pressure is below 8 GPa. This is consistent with the Hugoniot Elastic Limit (HEL) of 8.8 GPa estimated experimentally for silica glasses. Behind the shock front, the ring structure and the cavity distribution are impacted. The ring volume is smaller, and most cavities disappear with increasing shock pressure. However, the tetrahedral structure is not affected. The elasticity of the glass structure is therefore related to a ring shrinking and a cavity closing. Above the HEL, the shock pressure is high enough to impact the tetrahedral structure. An increasing number of hexahedrons and octahedrons are formed with the pressure. The large rings break to form smaller ones. The cavities are however not impacted as most cavities are already closed under an elastic shock. After the material relaxation, a significant amount of hexahedrons and octahedrons is still observed, and most of the cavities remain closed. The overall ring distribution after relaxation is similar to the equilibrium distribution. The densification process is therefore related to two structural mechanisms: a change in the coordination of silicon atoms and a cavity closing. To sum up, non-equilibrium molecular dynamics were carried out to investigate silica behaviour under shock loading. Analysing the structure lead to interesting conclusions upon the elastic and the densification mechanisms in glass materials. This work will be completed with a detailed study of the mechanism occurring above 30 GPa, where no sign of densification is observed after the material relaxation.

Keywords: densification, molecular dynamics simulations, shock loading, silica glass

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3500 Quantum Dots Incorporated in Biomembrane Models for Cancer Marker

Authors: Thiago E. Goto, Carla C. Lopes, Helena B. Nader, Anielle C. A. Silva, Noelio O. Dantas, José R. Siqueira Jr., Luciano Caseli

Abstract:

Quantum dots (QD) are semiconductor nanocrystals that can be employed in biological research as a tool for fluorescence imagings, having the potential to expand in vivo and in vitro analysis as cancerous cell biomarkers. Particularly, cadmium selenide (CdSe) magic-sized quantum dots (MSQDs) exhibit stable luminescence that is feasible for biological applications, especially for imaging of tumor cells. For these facts, it is interesting to know the mechanisms of action of how such QDs mark biological cells. For that, simplified models are a suitable strategy. Among these models, Langmuir films of lipids formed at the air-water interface seem to be adequate since they can mimic half a membrane. They are monomolecular films formed at liquid-gas interfaces that can spontaneously form when organic solutions of amphiphilic compounds are spread on the liquid-gas interface. After solvent evaporation, the monomolecular film is formed, and a variety of techniques, including tensiometric, spectroscopic and optic can be applied. When the monolayer is formed by membrane lipids at the air-water interface, a model for half a membrane can be inferred where the aqueous subphase serve as a model for external or internal compartment of the cell. These films can be transferred to solid supports forming the so-called Langmuir-Blodgett (LB) films, and an ampler variety of techniques can be additionally used to characterize the film, allowing for the formation of devices and sensors. With these ideas in mind, the objective of this work was to investigate the specific interactions of CdSe MSQDs with tumorigenic and non-tumorigenic cells using Langmuir monolayers and LB films of lipids and specific cell extracts as membrane models for diagnosis of cancerous cells. Surface pressure-area isotherms and polarization modulation reflection-absorption spectroscopy (PM-IRRAS) showed an intrinsic interaction between the quantum dots, inserted in the aqueous subphase, and Langmuir monolayers, constructed either of selected lipids or of non-tumorigenic and tumorigenic cells extracts. The quantum dots expanded the monolayers and changed the PM-IRRAS spectra for the lipid monolayers. The mixed films were then compressed to high surface pressures and transferred from the floating monolayer to solid supports by using the LB technique. Images of the films were then obtained with atomic force microscopy (AFM) and confocal microscopy, which provided information about the morphology of the films. Similarities and differences between films with different composition representing cell membranes, with or without CdSe MSQDs, was analyzed. The results indicated that the interaction of quantum dots with the bioinspired films is modulated by the lipid composition. The properties of the normal cell monolayer were not significantly altered, whereas for the tumorigenic cell monolayer models, the films presented significant alteration. The images therefore exhibited a stronger effect of CdSe MSQDs on the models representing cancerous cells. As important implication of these findings, one may envisage for new bioinspired surfaces based on molecular recognition for biomedical applications.

Keywords: biomembrane, langmuir monolayers, quantum dots, surfaces

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3499 Evaluation of Physical Parameters and in-Vitro and in-Vivo Antidiabetic Activity of a Selected Combined Medicinal Plant Extracts Mixture

Authors: S. N. T. I. Sampath, J. M. S. Jayasinghe, A. P. Attanayake, V. Karunaratne

Abstract:

Diabetes mellitus is one of the major public health posers throughout the world today that incidence and associated with increasing mortality. Insufficient regulation of the blood glucose level might be serious effects for health and its necessity to identify new therapeutics that have ability to reduce hyperglycaemic condition in the human body. Even though synthetic antidiabetic drugs are more effective to control diabetes mellitus, there are considerable side effects have been reported. Thus, there is an increasing demand for searching new natural products having high antidiabetic activity with lesser side effects. The purposes of the present study were to evaluate different physical parameters and in-vitro and in-vivo antidiabetic potential of the selected combined medicinal plant extracts mixture composed of leaves of Murraya koenigii, cloves of Allium sativum, fruits of Garcinia queasita and seeds of Piper nigrum. The selected plants parts were mixed and ground together and extracted sequentially into the hexane, ethyl acetate and methanol. Solvents were evaporated and they were further dried by freeze-drying to obtain a fine powder of each extract. Various physical parameters such as moisture, total ash, acid insoluble ash and water soluble ash were evaluated using standard test procedures. In-vitro antidiabetic activity of combined plant extracts mixture was screened using enzyme assays such as α-amylase inhibition assay and α-glucosidase inhibition assay. The acute anti-hyperglycaemic activity was performed using oral glucose tolerance test for the streptozotocin induced diabetic Wistar rats to find out in-vivo antidiabetic activity of combined plant extracts mixture and it was assessed through total oral glucose tolerance curve (TAUC) values. The percentage of moisture content, total ash content, acid insoluble ash content and water soluble ash content were ranged of 7.6-17.8, 8.1-11.78, 0.019-0.134 and 6.2-9.2 respectively for the plant extracts and those values were less than standard values except the methanol extract. The hexane and ethyl acetate extracts exhibited highest α-amylase (IC50 = 25.7 ±0.6; 27.1 ±1.2 ppm) and α-glucosidase (IC50 = 22.4 ±0.1; 33.7 ±0.2 ppm) inhibitory activities than methanol extract (IC50 = 360.2 ±0.6; 179.6 ±0.9 ppm) when compared with the acarbose positive control (IC50 = 5.7 ±0.4; 17.1 ±0.6 ppm). The TAUC values for hexane, ethyl acetate, and methanol extracts and glibenclamide (positive control) treated rats were 8.01 ±0.66; 8.05 ±1.07; 8.40±0.50; 5.87 ±0.93 mmol/L.h respectively, whereas in diabetic control rats the TAUC value was 13.22 ±1.07 mmol/L.h. Administration of plant extracts treated rats significantly suppressed (p<0.05) the rise in plasma blood glucose levels compared to control rats but less significant than glibenclamide. The obtained results from in-vivo and in-vitro antidiabetic study showed that the hexane and ethyl acetate extracts of selected combined plant mixture might be considered as a potential source to isolate natural antidiabetic agents and physical parameters of hexane and ethyl acetate extracts will helpful to develop antidiabetic drug with further standardize properties.

Keywords: diabetes mellitus, in-vitro antidiabetic assays, medicinal plants, standardization

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3498 Microwave Assisted Sol-gel Synthesis And Characterization Of Nanocrystalline Zirconia

Authors: Farzana Majid, Mahwish Bashir, Ammara, Attia Falak

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Zirconia nanoparticles have gained significant attention due to their excellent mechanical strength, thermal properties, biocompatibility, and catalytic activity. Tetragonal zirconia holds the greatest efficacy for surgical implants and coatings when it comes to the three zirconia phases (monoclinic, tetragonal, and cubic). However, its stability at higher temperatures and transformation to the monoclinic phase upon cooling are challenging. In this research, zirconia nanoparticles were prepared using microwave-assisted sol-gel method with varying microwave powers (100 W, 300 W, 500 W, 700 W, & 900 W). Organic stabilizing agent, i.e., eggshell powder, was used to stabilize the tetragonal phase. Fourier transform infrared spectroscopy (FTIR) confirmed the phase-pure tetragonal zirconia, corroborating the XRD data. Optical properties, including the optical bandgap, were studied using UV/Visible and PL spectroscopies. The synthesized ZrO2 nanoparticles exhibited excellent photocatalytic degradation efficiency in the degradation of methylene blue (MB) dye under UV irradiation. The findings demonstrate the potential of these ZrO2 nanoparticles as a viable alternative photocatalyst for the efficient degradation of various dyes in contaminated water.

Keywords: zirconia nanoparticles, sol-gel, photocataylsis, wter purification

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3497 Investigation of the Morphology and Optical Properties of CuAlO₂ Thin Film

Authors: T. M. Aminu, A. Salisu, B. Abdu, H. U. Alhassan, T. H. Dharma

Abstract:

Thin films of CuAlO2 were deposited on clean glass substrate using the chemical solution deposition (sol-gel) method of deposition with CuCl and AlCl3 taken as the starting materials. CuCl was dissolved in HCl while AlCl₃ in distilled water, pH value of the mixture was controlled by addition of NaOH. The samples were annealed at different temperatures in order to determine the effect of annealing temperatures on the morphological and optical properties of the deposited CuAlO₂ thin film. The surface morphology reveals an improved crystalline as annealing temperature increases. The results of the UV-vis and FT-IR spectrophotometry indicate that the absorbance for all the samples decreases sharply from a common value of about 89% at about 329 nm to a range of values of 56.2%-35.2% and the absorption / extinction coefficients of the films decrease with increase in annealing temperature from 1.58 x 10⁻⁶ to1.08 x 10⁻⁶ at about 1.14eV in the infrared region to about 1.93 x 10⁻⁶ to 1.29 x 10⁻⁶ at about 3.62eV in the visible region, the transmittance, reflectance and band gaps vary directly with annealing temperature, the deposited films were found to be suitable in optoelectronic applications.

Keywords: copper aluminium-oxide (CuAlO2), absorbance, transmittance, reflectance, band gaps

Procedia PDF Downloads 294
3496 A Piebald Cladistic Portray of Mitochondrial DNA Control Region Haplogroups in Khyber Pakhtunkhwa, Pakistan

Authors: Shahzad Bhatti, M. Aslamkhan, Sana Abbas, Marcella Attimonelli, Hikmet Hakan Aydin, Erica Martinha Silva de Souza,

Abstract:

Despite being situated at the crossroad of Asia, Pakistan has gained crucial importance because of its pivotal role in subsequent migratory events. To highlight the genetic footprints and to contribute an enigmatic picture of the relative population expansion pattern among four major Pashtun tribes in Khyber Pakhtunkhwa viz., Bangash, Khattak, Mahsuds and Orakzai, the complete mitochondrial control region of 100 Pashtun were analyzed. All Pashtun tribes studied here revealed high genetic diversity; that was comparable to the other Central Asian, Southeast Asian and European populations. The configuration of genetic variation and heterogeneity further unveiled through Multidimensional Scaling, Principal Component Analysis, and phylogenetic analysis. The results revealed that the Pashtun is a composite mosaic of West Eurasian ancestry of numerous geographic origin. They received substantial gene flow during different invasions and have a high element of the Western provenance. The most common haplogroups reported in this study are: South Asian haplogroup M (28%) and R (8%); whereas, West Asians haplogroups are present, albeit in high frequencies (67%) and widespread over all; HV (15%), U (17%), H (9%), J (8%), K (8%), W (4%), N (3%) and T (3%). Herein we linked the unexplored genetic connection between Ashkenazi Jews and Pashtun. The presence of specific haplotypes J1b (4%) and K1a1b1a (5%) point to a genetic connection of Jewish conglomeration with Khattak tribe. This was a result of an ancient genetic influx in the early Neolithic period that led to the formation of a diverse genetic substratum in present day Pashtun.

Keywords: mtDNA haplogroups, control region, Pakistan, KPK, ethnicity

Procedia PDF Downloads 481
3495 Fatigue Behavior of Friction Stir Welded EN AW 5754 Aluminum Alloy Using Load Increase Procedure

Authors: A. B. Chehreh, M. Grätzel, M. Klein, J. P. Bergmann, F. Walther

Abstract:

Friction stir welding (FSW) is an advantageous method in the thermal joining processes, featuring the welding of various dissimilar and similar material combinations, joining temperatures below the melting point which prevents irregularities such as pores and hot cracks as well as high strengths mechanical joints near the base material. The FSW process consists of a rotating tool which is made of a shoulder and a probe. The welding process is based on a rotating tool which plunges in the workpiece under axial pressure. As a result, the material is plasticized by frictional heat which leads to a decrease in the flow stress. During the welding procedure, the material is continuously displaced by the tool, creating a firmly bonded weld seam behind the tool. However, the mechanical properties of the weld seam are affected by the design and geometry of the tool. These include in particular microstructural and surface properties which can favor crack initiation. Following investigation compares the dynamic properties of FSW weld seams with conventional and stationary shoulder geometry based on load increase test (LIT). Compared to classical Woehler tests, it is possible to determine the fatigue strength of the specimens after a short amount of time. The investigations were carried out on a robotized welding setup on 2 mm thick EN AW 5754 aluminum alloy sheets. It was shown that an increased tensile and fatigue strength can be achieved by using the stationary shoulder concept. Furthermore, it could be demonstrated that the LIT is a valid method to describe the fatigue behavior of FSW weld seams.

Keywords: aluminum alloy, fatigue performance, fracture, friction stir welding

Procedia PDF Downloads 153
3494 Green Supply Chain Network Optimization with Internet of Things

Authors: Sema Kayapinar, Ismail Karaoglan, Turan Paksoy, Hadi Gokcen

Abstract:

Green Supply Chain Management is gaining growing interest among researchers and supply chain management. The concept of Green Supply Chain Management is to integrate environmental thinking into the Supply Chain Management. It is the systematic concept emphasis on environmental problems such as reduction of greenhouse gas emissions, energy efficiency, recycling end of life products, generation of solid and hazardous waste. This study is to present a green supply chain network model integrated Internet of Things applications. Internet of Things provides to get precise and accurate information of end-of-life product with sensors and systems devices. The forward direction consists of suppliers, plants, distributions centres and sales and collect centres while, the reverse flow includes the sales and collects centres, disassembled centre, recycling and disposal centre. The sales and collection centre sells the new products are transhipped from factory via distribution centre and also receive the end-of life product according their value level. We describe green logistics activities by presenting specific examples including “recycling of the returned products and “reduction of CO2 gas emissions”. The different transportation choices are illustrated between echelons according to their CO2 gas emissions. This problem is formulated as a mixed integer linear programming model to solve the green supply chain problems which are emerged from the environmental awareness and responsibilities. This model is solved by using Gams package program. Numerical examples are suggested to illustrate the efficiency of the proposed model.

Keywords: green supply chain optimization, internet of things, greenhouse gas emission, recycling

Procedia PDF Downloads 328
3493 Runoff Estimation in the Khiyav River Basin by Using the SCS_ CN Model

Authors: F. Esfandyari Darabad, Z. Samadi

Abstract:

The volume of runoff caused by rainfall in the river basin has enticed the researchers in the fields of the water management resources. In this study, first of the hydrological data such as the rainfall and discharge of the Khiyav river basin of Meshkin city in the northwest of Iran collected and then the process of analyzing and reconstructing has been completed. The soil conservation service (scs) has developed a method for calculating the runoff, in which is based on the curve number specification (CN). This research implemented the following model in the Khiyav river basin of Meshkin city by the GIS techniques and concluded the following fact in which represents the usage of weight model in calculating the curve numbers that provides the possibility for the all efficient factors which is contributing to the runoff creation such as; the geometric characteristics of the basin, the basin soil characteristics, vegetation, geology, climate and human factors to be considered, so an accurate estimation of runoff from precipitation to be achieved as the result. The findings also exposed the accident-prone areas in the output of the Khiyav river basin so it was revealed that the Khiyav river basin embodies a high potential for the flood creation.

Keywords: curve number, khiyav river basin, runoff estimation, SCS

Procedia PDF Downloads 622
3492 Analysis of Transformer Reactive Power Fluctuations during Adverse Space Weather

Authors: Patience Muchini, Electdom Matandiroya, Emmanuel Mashonjowa

Abstract:

A ground-end manifestation of space weather phenomena is known as geomagnetically induced currents (GICs). GICs flow along the electric power transmission cables connecting the transformers and between the grounding points of power transformers during significant geomagnetic storms. Geomagnetically induced currents have been studied in other regions and have been noted to affect the power grid network. In Zimbabwe, grid failures have been experienced, but it is yet to be proven if these failures have been due to GICs. The purpose of this paper is to characterize geomagnetically induced currents with a power grid network. This paper analyses data collected, which is geomagnetic data, which includes the Kp index, DST index, and the G-Scale from geomagnetic storms and also analyses power grid data, which includes reactive power, relay tripping, and alarms from high voltage substations and then correlates the data. This research analysis was first theoretically analyzed by studying geomagnetic parameters and then experimented upon. To correlate, MATLAB was used as the basic software to analyze the data. Latitudes of the substations were also brought into scrutiny to note if they were an impact due to the location as low latitudes areas like most parts of Zimbabwe, there are less severe geomagnetic variations. Based on theoretical and graphical analysis, it has been proven that there is a slight relationship between power system failures and GICs. Further analyses can be done by implementing measuring instruments to measure any currents in the grounding of high-voltage transformers when geomagnetic storms occur. Mitigation measures can then be developed to minimize the susceptibility of the power network to GICs.

Keywords: adverse space weather, DST index, geomagnetically induced currents, KP index, reactive power

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3491 Assessment of Pollution Cd, Pb and as in Rice Cultivation in Savadkooh

Authors: Ghazal Banitahmasb, Nazanin Khakipour

Abstract:

More than 90 percent of the world's rice is produced and consumed in Asia. Heavy metal contamination of soil and water environments is a serious and growing problem. Toxin by human activities causes pollution in soils so that the intensity of metals in soils was exceeded. This study was done on 7 samples of rice cultivated in Savadkooh of Mazandaran province and soils; they were grown. The amount of heavy metals Arsenic, Lead and Cadmium were measured by atomic absorption. The test results showed that the amount of Lead in rice strain, Tarom A, was 0.768 ppm, the maximum amount of Cadmium in rice strain, Hashemi B, was 0.09 ppm and the highest levels of Arsenic was in red Tarom, 0.39 ppm. According to the results obtained in this study can be found all rice grown in Savadkooh city of Arsenic, Cadmium and Lead, but the measurements are less than specified in the national standard, and their use is safe for consumers. These results also indicate that positive and significant correlation between the studied heavy metals in soil and rice strains that grow there and by increasing the amount of heavy metals in the soil, the amount of these metals in crops grown on them is also increasing.

Keywords: heavy metals, Oryza sativa L., soil pollution, Savadkooh

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3490 Traction Behavior of Linear Piezo-Viscous Lubricants in Rough Elastohydrodynamic Lubrication Contacts

Authors: Punit Kumar, Niraj Kumar

Abstract:

The traction behavior of lubricants with the linear pressure-viscosity response in EHL line contacts is investigated numerically for smooth as well as rough surfaces. The analysis involves the simultaneous solution of Reynolds, elasticity and energy equations along with the computation of lubricant properties and surface temperatures. The temperature modified Doolittle-Tait equations are used to calculate viscosity and density as functions of fluid pressure and temperature, while Carreau model is used to describe the lubricant rheology. The surface roughness is assumed to be sinusoidal and it is present on the nearly stationary surface in near-pure sliding EHL conjunction. The linear P-V oil is found to yield much lower traction coefficients and slightly thicker EHL films as compared to the synthetic oil for a given set of dimensionless speed and load parameters. Besides, the increase in traction coefficient attributed to surface roughness is much lower for the former case. The present analysis emphasizes the importance of employing realistic pressure-viscosity response for accurate prediction of EHL traction.

Keywords: EHL, linear pressure-viscosity, surface roughness, traction, water/glycol

Procedia PDF Downloads 382
3489 Sky Farming: The Alternative Concept of Green Building Using Vertical Landscape Model in Urban Area as an Effort to Achieve Sustainable Development

Authors: Nadiah Yola Putri, Nesia Putri Sharfina, Traviata Prakarti

Abstract:

This paper is a literature review presented descriptively to review the concept of green building to face the challenge of sustainable development and food in urban areas. In this paper, researchers initiated the concept of green building with sky farming method. Sky farming use vertical landscape system in order to realizing food self-sufficient green city. Sky farming relying on plantings and irrigation system efficiency in the building which is adopted the principles of green building. Planting system is done by applying hydroponic plants with Nutrient Film Technique (NFT) using energy source of solar cell and grey water from the processing of waste treatment plant. The application of sky farming in urban areas can be a recommendation for the design of environmental-friendly construction. In order to keep the land and distance efficiency, this system is a futuristic idea that would be the connector of human civilization in the future.

Keywords: green building, urban area, sky farming, vertical landscape

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3488 External Vacuum Dressing: Optimising Non-Operative Management of Flail Sternum Post CPR

Authors: Nicholas Bayfield, Mark Newman

Abstract:

Case Presentation: A 48-year-old male was brought in by ambulance after an out-of-hospital cardiac arrest, with 20 minutes of good-quality cardiopulmonary resuscitation in the community. Return of spontaneous circulation was achieved with defibrillation, revealing an inferior ST-elevation myocardial infarction. He was revascularized emergently in the cath lab and stabilised. Following the procedure, he was noted to have paradoxical respiratory movements of the sternum and high oxygen requirements. CT imaging demonstrated a flail chest with bilateral anterior rib 1-7 fractures as well as a large left-sided extra-pleural haematoma and small haemopneumothorax, secondary to CPR. The patient’s ventilation was stabilised with oxygen via a high-flow humidifier. Pain relief was provided. The anatomy of his rib fractures was not easily amenable to operative fixation. In addition, he was considered to be a high-risk operative candidate due to his recent arrest. He was managed thus non-operatively with an external vacuum dressing applied to the anterior chest wall to minimise respiratory compromise and minimise pain from the motion around the rib fracture sites. Non-operative management was successful, and the patient was reviewed one month later. The paradoxical sternal movement had abated. Discussion: External vacuum dressing has been trialled for non-operative management of rib fractures with varying success. It provides an external brace to minimise fracture site movement during respiration and coughing, thus minimising pain. This modality should be considered a low-cost, high-reward adjunct to non-operative management of bony thoracic trauma.

Keywords: thoracic surgery, thoracic trauma, rib fractures, negative pressure dressing

Procedia PDF Downloads 154
3487 The Contribution of Lower Visual Channels and Evolutionary Origin of the Tunnel Effect

Authors: Shai Gabay

Abstract:

The tunnel effect describes the phenomenon where a moving object seems to persist even when temporarily hidden from view. Numerous studies indicate that humans, infants, and nonhuman primates possess object persistence, relying on spatiotemporal cues to track objects that are dynamically occluded. While this ability is associated with neural activity in the cerebral neocortex of humans and mammals, the role of subcortical mechanisms remains ambiguous. In our current investigation, we explore the functional contribution of monocular aspects of the visual system, predominantly subcortical, to the representation of occluded objects. This is achieved by manipulating whether the reappearance of an object occurs in the same or different eye from its disappearance. Additionally, we employ Archerfish, renowned for their precision in dislodging insect prey with water jets, as a phylogenetic model to probe the evolutionary origins of the tunnel effect. Our findings reveal the active involvement of subcortical structures in the mental representation of occluded objects, a process evident even in species that do not possess cortical tissue.

Keywords: archerfish, tunnel effect, mental representations, monocular channels, subcortical structures

Procedia PDF Downloads 45
3486 The Effect of Mgo and Rubber Nanofillers on Electrical Treeing Characteristic of XLPE Based Nanocomposites

Authors: Nur Amira nor Arifin, Tashia Marie Anthony, Mohd Ruzlin Mokhtar, Huzainie Shafi Abd Halim

Abstract:

Cross-linked polyethylene (XLPE) material is being used as the cable insulation for the past decades due to its higher working temperature of 90 ˚C and some other advantages. However, the use of XLPE as an insulating material for underground distribution cables may have subjected to the unforeseeable weather and uncontrollable environmental condition. These unfavorable condition when combine with high electric field may lead to the initiation and growth of water tree in XLPE insulation. There are several studies on numerous nanofillers incorporate into polymer matrix to hinder the growth of tree propagation. Hence, in this study aims to investigate the effect of MgO and rubber nanofillers at different concentration on the electrical tree of XLPE. The nanofillers and XLPE were mixed and later extruded. After extrusion, the material were then fabricated into the desired shape for experimental purposes. The result shows that the electrical tree propagation of XLPE filled with optimize concentration of nanofillers were much slower compared to pure XLPE. In this paper, the effect of nanofillers towards electrical treeing characteristic will be discussed.

Keywords: electrical trees, nanofillers, polymer nanocomposites, XLPE

Procedia PDF Downloads 140