Search results for: transmission line outages
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4408

Search results for: transmission line outages

1468 Flexible PVC Based Nanocomposites With the Incorporation of Electric and Magnetic Nanofillers for the Shielding Against EMI and Thermal Imaging Signals

Authors: H. M. Fayzan Shakir, Khadija Zubair, Tingkai Zhao

Abstract:

Electromagnetic (EM) waves are being used widely now a days. Cell phone signals, WIFI signals, wireless telecommunications etc everything uses EM waves which then create EM pollution. EM pollution can cause serious effects on both human health and nearby electronic devices. EM waves have electric and magnetic components that disturb the flow of charged particles in both human nervous system and electronic devices. The shielding of both humans and electronic devices are a prime concern today. EM waves can cause headaches, anxiety, suicide and depression, nausea, fatigue and loss of libido in humans and malfunctioning in electronic devices. Polyaniline (PANI) and polypyrrole (PPY) were successfully synthesized using chemical polymerizing using ammonium persulfate and DBSNa as oxidant respectively. Barium ferrites (BaFe) were also prepared using co-precipitation method and calcinated at 10500C for 8h. Nanocomposite thin films with various combinations and compositions of Polyvinylchloride, PANI, PPY and BaFe were prepared. X-ray diffraction technique was first used to confirm the successful fabrication of all nano fillers and particle size analyzer to measure the exact size and scanning electron microscopy is used for the shape. According to Electromagnetic Interference theory, electrical conductivity is the prime property required for the Electromagnetic Interference shielding. 4-probe technique is then used to evaluate DC conductivity of all samples. Samples with high concentration of PPY and PANI exhibit remarkable increased electrical conductivity due to fabrication of interconnected network structure inside the Polyvinylchloride matrix that is also confirmed by SEM analysis. Less than 1% transmission was observed in whole NIR region (700 nm – 2500 nm). Also, less than -80 dB Electromagnetic Interference shielding effectiveness was observed in microwave region (0.1 GHz to 20 GHz).

Keywords: nanocomposites, polymers, EMI shielding, thermal imaging

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1467 Uranium Migration Process: A Multi-Technique Investigation Strategy for a Better Understanding of the Role of Colloids

Authors: Emmanuelle Maria, Pierre Crançon, Gaëtane Lespes

Abstract:

The knowledge of uranium migration processes within underground environments is a major issue in the environmental risk assessment associated with nuclear activities. This process is identified as strongly controlled by adsorption mechanisms, thus leading to strongly delayed migration paths. Colloidal ligands are likely to significantly increase the mobility of uranium in natural environments. The ability of colloids to mobilize and transport uranium depends on their origin, their nature, their structure, their stability and their reactivity with uranium. Thus, the colloidal mobilization and transport properties are often described as site-specific. In this work, the colloidal phases of two leachates obtained from two different horizons of the same podzolic soil were characterized with a speciation approach. For this purpose, a multi-technique strategy was used, based on Field-Flow Fractionation coupled to Ultraviolet, Multi-Angle Light Scattering and Inductively Coupled Plasma Mass Spectrometry (AF4-UV-MALS-ICPMS), Transmission Electron Microscopy (TEM), Electrospray Ionization Orbitrap Mass Spectrometry (ESI-Orbitrap), and Time-Resolved Laser Fluorescence Spectroscopy (TRLFS-EEM). Thus, elemental composition, size distribution, microscopic structure, colloidal stability and possible organic and/or inorganic content of colloids were determined, as well as their association with uranium. The leachates exhibit differences in their physical and chemical characteristics, mainly in the nature of organic matter constituents. The multi-technique investigation strategy used provides original data about colloidal phase structure and composition, offering a new vision of the way the uranium can be mobilized and transported in the considered soil. This information is a real significant contribution opening the way to our understanding and predicting of the colloidal transport.

Keywords: colloids, migration, multi-technique, speciation, transport, uranium

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1466 Advanced Bio-Composite Materials Based on Biopolymer Blends and Cellulose Nanocrystals

Authors: Zineb Kassab, Nassima El Miri, A. Aboulkas, Abdellatif Barakat, Mounir El Achaby

Abstract:

Recently, more attention has been given to biopolymers with a focus on sustainable development and environmental preservation. Following this tendency, the attempt has been made to replace polymers derived from petroleum with superior biodegradable polymers (biopolymers). In this context, biopolymers are considered potential replacements for conventional plastic materials. However, some of their properties must be improved for better competitiveness, especially regarding their mechanical, thermal and barrier properties. Bio-nanocomposite technology using nanofillers has already been proven as an effective way to produce new materials with specific properties and high performances. With the emergence of nanostructured bio-composite materials, incorporating elongated rod-like cellulose nanocrystals (CNC) has attracted more and more attention in the field of nanotechnology. This study is aimed to develop bio-composite films of biopolymer matrices [Carboxymethyle cellulose (CMC), Starch (ST), Chitosan (CS) and Polyvinyl alcohol (PVA)] reinforced with cellulose nanocrystals (CNC) using the solution casting method. The CNC were extracted at a nanometric scale from lignocellulosic fibers via sulfuric acid hydrolysis and then characterized using X-ray diffraction (XRD), thermogravimetric analysis (TGA), confocal microscopy, infrared spectroscopy (IR), atomic force and transmission electron microscopies (AFM and TEM) techniques. The as extracted CNC were used as a reinforcing phase to produce a variety of bio-composite films at different CNC loading (0.5-10 wt %) with specific properties. The rheological properties of film-forming solutions (FFS) of bio-composites were studied, and their relation to the casting process was evaluated. Then, the structural, optical transparency, water vapor permeability, thermal stability and mechanical properties of all prepared bio-composite films were evaluated and studied in this report. The high performances of these bio-composite films are expected to have potential in biomaterials or packaging applications.

Keywords: biopolymer composites, cellulose nanocrystals, food packaging, lignocellulosic fibers

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1465 Education in Schools and Public Policy in India

Authors: Sujeet Kumar

Abstract:

Education has greater importance particularly in terms of increasing human capital and economic competitiveness. It plays a crucial role in terms of cognitive and skill development. Its plays a vital role in process of socialization, fostering social justice, and enhancing social cohesion. Policy related to education has been always a priority for developed countries, which is later adopted by developing countries also. The government of India has also brought change in education polices in line with recognizing change at national and supranational level. However, quality education is still not become an open door for every child in India and several reports are produced year to year about level of school education in India. This paper is concerned with schooling in India. Particularly, it focuses on two government and two private schools in Bihar, but reference has made to schools in Delhi especially around slum communities. The paper presents brief historical context and an overview of current school systems in India. Later, it focuses on analysis of current development in policy in reference with field observation, which is anchored around choice, diversity, market – orientation and gap between different groups of pupils. There is greater degree of difference observed at private and government school levels in terms of quality of teachers, method of teaching and overall environment of learning. The paper concludes that the recent policy development in education particularly Sarva Siksha Abhiyaan (SAA) and Right to Education Act (2009) has required renovating new approach to bridge the gap through broader consultation at grassroots and participatory approach with different stakeholders.

Keywords: education, public policy, participatory approach

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1464 Power Production Performance of Different Wave Energy Converters in the Southwestern Black Sea

Authors: Ajab G. Majidi, Bilal Bingölbali, Adem Akpınar

Abstract:

This study aims to investigate the amount of energy (economic wave energy potential) that can be obtained from the existing wave energy converters in the high wave energy potential region of the Black Sea in terms of wave energy potential and their performance at different depths in the region. The data needed for this purpose were obtained using the calibrated nested layered SWAN wave modeling program version 41.01AB, which was forced with Climate Forecast System Reanalysis (CFSR) winds from 1979 to 2009. The wave dataset at a time interval of 2 hours was accumulated for a sub-grid domain for around Karaburun beach in Arnavutkoy, a district of Istanbul city. The annual sea state characteristic matrices for the five different depths along with a vertical line to the coastline were calculated for 31 years. According to the power matrices of different wave energy converter systems and characteristic matrices for each possible installation depth, the probability distribution tables of the specified mean wave period or wave energy period and significant wave height were calculated. Then, by using the relationship between these distribution tables, according to the present wave climate, the energy that the wave energy converter systems at each depth can produce was determined. Thus, the economically feasible potential of the relevant coastal zone was revealed, and the effect of different depths on energy converter systems is presented. The Oceantic at 50, 75 and 100 m depths and Oyster at 5 and 25 m depths presents the best performance. In the 31-year long period 1998 the most and 1989 is the least dynamic year.

Keywords: annual power production, Black Sea, efficiency, power production performance, wave energy converter

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1463 Statistical Modeling of Local Area Fading Channels Based on Triply Stochastic Filtered Marked Poisson Point Processes

Authors: Jihad Daba, Jean-Pierre Dubois

Abstract:

Multi path fading noise degrades the performance of cellular communication, most notably in femto- and pico-cells in 3G and 4G systems. When the wireless channel consists of a small number of scattering paths, the statistics of fading noise is not analytically tractable and poses a serious challenge to developing closed canonical forms that can be analysed and used in the design of efficient and optimal receivers. In this context, noise is multiplicative and is referred to as stochastically local fading. In many analytical investigation of multiplicative noise, the exponential or Gamma statistics are invoked. More recent advances by the author of this paper have utilized a Poisson modulated and weighted generalized Laguerre polynomials with controlling parameters and uncorrelated noise assumptions. In this paper, we investigate the statistics of multi-diversity stochastically local area fading channel when the channel consists of randomly distributed Rayleigh and Rician scattering centers with a coherent specular Nakagami-distributed line of sight component and an underlying doubly stochastic Poisson process driven by a lognormal intensity. These combined statistics form a unifying triply stochastic filtered marked Poisson point process model.

Keywords: cellular communication, femto and pico-cells, stochastically local area fading channel, triply stochastic filtered marked Poisson point process

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1462 Reducing The Frequency of Flooding Accompanied by Low pH Wastewater In 100/200 Unit of Phosphate Fertilizer 1 Plant by Implementing The 3R Program (Reduce, Reuse and Recycle)

Authors: Pradipta Risang Ratna Sambawa, Driya Herseta, Mahendra Fajri Nugraha

Abstract:

In 2020, PT Petrokimia Gresik implemented a program to increase the ROP (Run Of Pile) production rate at the Phosphate Fertilizer 1 plant, causing an increase in scrubbing water consumption in the 100/200 area unit. This increase in water consumption causes a higher discharge of wastewater, which can further cause local flooding, especially during the rainy season. The 100/200 area of the Phosphate Fertilizer 1 plant is close to the warehouse and is often a passing area for trucks transporting raw materials. This causes the pH in the wastewater to become acidic (the worst point is up to pH 1). The problem of flooding and exposure to acidic wastewater in the 100/200 area of Phosphate Fertilizer Plant 1 was then resolved by PT Petrokimia Gresik through wastewater optimization steps called the 3R program (Reduce, Reuse, and Recycle). The 3R (Reduce, reuse, and recycle) program consists of an air consumption reduction program by considering the liquid/gas ratio in scrubbing unit of 100/200 Phosphate Fertilizer 1 plant, creating a wastewater interconnection line so that wastewater from unit 100/200 can be used as scrubbing water in the Phonska 1, Phonska 2, Phonska 3 and unit 300 Phosphate Fertilizer 1 plant and increasing scrubbing effectiveness through scrubbing effectiveness simulations. Through a series of wastewater optimization programs, PT Petrokimia Gresik has succeeded in reducing NaOH consumption for neutralization up to 2,880 kg/day or equivalent in saving up to 314,359.76 dollars/year and reducing process water consumption up to 600 m3/day or equivalent in saving up to 63,739.62 dollars/year.

Keywords: fertilizer, phosphate fertilizer, wastewater, wastewater treatment, water management

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1461 Effects of Tomato-Crispy Salad Intercropping on Diameter of Tomato Fruits under Greenhouse Conditions

Authors: Halil Demir, Ersin Polat

Abstract:

This study, in which crispy salad plants was cultivated between the two rows of tomato, was conducted in Spring 2007 in a research glasshouse at Akdeniz University. Crispy salad (Lactuca sativa var. crispa cv. Bohemia) plants were intercropped with tomato (Solanum lycopersicon cv. Selin F1) plants as the main crop. Tomato seedlings were planted according to double line plantation system with 100 cm large spacing, 50 cm narrow spacing and 50 cm within row plant spacing. In both control and intercropping applications, each plot was 9.75 m2 according to plantation distances and there were 26 plants per each plot for tomato. Crispy salad seedlings were planted with 30 cm spacing as one row in the middle of tomato plants and with 30x30 spacing as two rows between plants rows. Moreover, salad seedlings were transplanted between tomato plants above the tomato rows that were planted in two rows with intervals of 50 cm and also with 25x25 cm spacing as the third row in the middle of tomato rows. While tomato plants were growing during the research, fruit width and height were measured periodically with 15 days in the tomato fruits of the third cluster from the formation of fruit to fruit ripening. According to results, while there were no differences between cropping systems in terms of fruit width, the highest fruit height was found in Control trial in the first measurement. In the second measurement while the highest fruit width was determined with 64.39 mm in Control, there were no differences between cropping systems. In the third measurement, the highest fruit width and height were obtained from Control with 68.47 mm and 55.52 mm, respectively. As a conclusion the trial, which crispy salad seedlings were planted with 30x30 cm spacing as two rows between tomato plants rows, was determined as a best intercropping application.

Keywords: crispy salad, glasshouse, intercropping, tomato

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1460 Angiogenic and Immunomodulatory Properties and Phenotype of Mesenchymal Stromal Cells Can Be Regulated by Cytokine Treatment

Authors: Ekaterina Zubkova, Irina Beloglazova, Iurii Stafeev, Konsyantin Dergilev, Yelena Parfyonova, Mikhail Menshikov

Abstract:

Mesenchymal stromal cells from adipose tissue (MSC) currently are widely used in regenerative medicine to restore the function of damaged tissues, but that is significantly hampered by their heterogeneity. One of the modern approaches to overcoming this obstacle is the polarization of cell subpopulations into a specific phenotype under the influence of cytokines and other factors that activate receptors and signal transmission to cells. We polarized MSC with factors affecting the inflammatory signaling and functional properties of cells, followed by verification of their expression profile and ability to affect the polarization of macrophages. RT-PCR evaluation showed that cells treated with LPS, interleukin-17, tumor necrosis factor α (TNF α), primarily express pro-inflammatory factors and cytokines, and after treatment with polyninosin polycytidic acid and interleukin-4 (IL4) anti-inflammatory factors and some proinflammatory factors. MSC polarized with pro-inflammatory cytokines showed a more robust pro-angiogenic effect in fibrin gel bead 3D angiogenesis assay. Further, we evaluated the possibility of paracrine effects of MSCs on the polarization of intact macrophages. Polarization efficiency was assesed by expression of M1/M2 phenotype markers CD80 and CD206. We showed that conditioned media from MSC preincubated in the presence of IL-4 cause an increase in CD206 expression similar to that observed in M2 macrophages. Conditioned media from MSC polarized in the presence of LPS or TNF-α increased the expression of CD80 antigen in macrophages, similar to that observed in M1 macrophages. In other cases, a pronounced paracrine effect of MSC on the polarization of macrophages was not detected. Thus, our study showed that the polarization of MSC along the pro-inflammatory or anti-inflammatory pathway allows us to obtain cell subpopulations that have a multidirectional modulating effect on the polarization of macrophages. (RFBR grants 20-015-00405 and 18-015-00398.)

Keywords: angiogenesis, cytokines, mesenchymal, polarization, inflammation

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1459 Assessment of Heavy Metals and Radionuclide Concentrations in Mafikeng Waste Water Treatment Plant

Authors: M. Mathuthu, N. N. Gaxela, R. Y. Olobatoke

Abstract:

A study was carried out to assess the heavy metal and radionuclide concentrations of water from the waste water treatment plant in Mafikeng Local Municipality to evaluate treatment efficiency. Ten water samples were collected from various stages of water treatment which included sewage delivered to the plant, the two treatment stages and the effluent and also the community. The samples were analyzed for heavy metal content using Inductive Coupled Plasma Mass Spectrometer. Gross α/β activity concentration in water samples was evaluated by Liquid Scintillation Counting whereas the concentration of individual radionuclides was measured by gamma spectroscopy. The results showed marked reduction in the levels of heavy metal concentration from 3 µg/L (As)–670 µg/L (Na) in sewage into the plant to 2 µg/L (As)–170 µg/L (Fe) in the effluent. Beta activity was not detected in water samples except in the in-coming sewage, the concentration of which was within reference limits. However, the gross α activity in all the water samples (7.7-8.02 Bq/L) exceeded the 0.1 Bq/L limit set by World Health Organization (WHO). Gamma spectroscopy analysis revealed very high concentrations of 235U and 226Ra in water samples, with the lowest concentrations (9.35 and 5.44 Bq/L respectively) in the in-coming sewage and highest concentrations (73.8 and 47 Bq/L respectively) in the community water suggesting contamination along water processing line. All the values were considerably higher than the limits of South Africa Target Water Quality Range and WHO. However, the estimated total doses of the two radionuclides for the analyzed water samples (10.62 - 45.40 µSv yr-1) were all well below the reference level of the committed effective dose of 100 µSv yr-1 recommended by WHO.

Keywords: gross α/β activity, heavy metals, radionuclides, 235U, 226Ra, water sample

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1458 Consequence of Multi-Templating of Closely Related Structural Analogues on a Chitosan-Methacryllic Acid Molecularly Imprinted Polymer Matrix-Thermal and Chromatographic Traits

Authors: O.Ofoegbu, S. Roongnapa, A.N. Eboatu

Abstract:

Most polluted environments, most challengingly, aerosol types, contain a cocktail of different toxicants. Multi-templating of matrices have been the recent target by researchers in a bid to solving complex mixed-toxicant challenges using single or common remediation systems. This investigation looks at the effect of such multi-templated system vis-a-vis the synthesis by non-covalent interaction, of a molecularly imprinted polymer architecture using nicotine and its structural analogue Phenylalanine amide individually and, in the blend, (50:50), as template materials in a Chitosan-Methacrylic acid functional monomer matrix. The temperature for polymerization is 60OC and time for polymerization, 12hrs (water bath heating), 4mins for (microwave heating). The characteristic thermal properties of the molecularly imprinted materials are investigated using Simultaneous Thermal Analysis (STA) profiling, while the absorption and separation efficiencies based on the relative retention times and peak areas of templates were studied amongst other properties. Transmission Electron Microscopy (TEM) results obtained, show the creation of heterogeneous nanocavities, regardless, the introduction of Caffeine a close structural analogue presented near-zero perfusion. This confirms the selectivity and specificity of the templated polymers despite its dual-templated nature. The STA results presented the materials as having decomposition temperatures above 250OC and a relative loss in mass of less than19% over a period within 50mins of heating. Consequent to this outcome, multi-templated systems can be fabricated to sequester specifically and selectively targeted toxicants in a mixed toxicant populated system effectively.

Keywords: chitosan, dual-templated, methacrylic acid, mixed-toxicants, molecularly-imprinted-polymer

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1457 Enhanced Exchange Bias in Poly-crystalline Compounds through Oxygen Vacancy and B-site Disorder

Authors: Koustav Pal, Indranil Das

Abstract:

In recent times, perovskite and double perovskite (DP) systems attracts lot of interest as they provide a rich material platform for studying emergent functionalities like near-room-temperature ferromagnetic (FM) insulators, exchange bias (EB), magnetocaloric effects, colossal magnetoresistance, anisotropy, etc. These interesting phenomena emerge because of complex couplings between spin, charge, orbital, and lattice degrees of freedom in these systems. Various magnetic phenomena such as exchange bias, spin glass, memory effect, colossal magneto-resistance, etc. can be modified and controlled through antisite (B-site) disorder or controlling oxygen concentration of the material. By controlling oxygen concentration in SrFe0.5Co0.5O3 – δ (SFCO) (δ ∼ 0.3), we achieve intrinsic exchange bias effect with a large exchange bias field (∼1.482 Tesla) and giant coercive field (∼1.454 Tesla). Now we modified the B-site by introducing 10% iridium in the system. This modification give rise to the exchange bias field as high as 1.865 tesla and coercive field 1.863 tesla. Our work aims to investigate the effect of oxygen deficiency and B-site effect on exchange bias in oxide materials for potential technological applications. Structural characterization techniques including X-ray diffraction, scanning tunneling microscopy, and transmission electron microscopy were utilized to determine crystal structure and particle size. X-ray photoelectron spectroscopy was used to identify valence states of the ions. Magnetic analysis revealed that oxygen deficiency resulted in a large exchange bias due to a significant number of ionic mixtures. Iridium doping was found to break interaction paths, resulting in various antiferromagnetic and ferromagnetic surfaces that enhance exchange bias.

Keywords: coercive field, disorder, exchange bias, spin glass

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1456 Chemical Composition and Biological Investigation of Halpophyllum tuberculatum A. Juss (Rutaceae) Essential Oils Growing in Libya

Authors: O. M. M. Sabry, Abeer M. El Sayed

Abstract:

The essential oils from the aerial parts and flowers of Haplophyllum tuberculatum (Forsskal) Adr. Juss (Rutaceae) growing in Libya were obtained separately by hydro-distillation using a Clevenger-type apparatus. The essential oils yield were (0.4, 1.5w/w%) respectively based on the dry weight of the plant. The oils were analyzed by GC-MS. Twenty four constituents, amounting to 96.6%, were identified in the oil of the aerial parts. The predominant compounds were among the non oxygenated terpenoids (82.4%) as monoterpene hydrocarbons, represented by sabinen (26.4 %), δ-terpinen (26 %), β-phellandrene (10.4%) and 3-carene (3.86%). Zingiberine (0.4%) and β-sesquiphellandrene (0.12%) were the major sesquiterpene hydrocarbons identified. Oxygenated monoterpenes were represented by eucalyptol (5.5%) and piperitone (5.55%). Twenty six constituents, equivalent to 99.5%, were identified in the oil of the flowers. The dominance of monoterpene hydrocarbons in the flowers oil can be attributed to the high percentage of γ-terpinen (38.44%), β-phellandrene (10.0%), α- phellandrene (2.33%), 3,4-dimethyl-1,5-cyclooctadiene (6.67%), β-myrecene (6.04%), 3-carene (5.43%) and α-pinene (1.3%).While the oxygenated monoterpenes can be contributed to the trans-piperitol (4.67%) and piperitone (2.07%). Sesquiterpene hydrocarbons were not identified in the oil of the flower of H. tuberculatum. Variation in constitution between oils of Libyan H. tuberculatum and that obtained from other countries can be due to both environmental and genetic factors. The essential oils have demonstrated variable antimicrobial activities against certain micro-organisms. Also have revealed marked in vitro cytotoxicity against lung (H1299), liver (HEPG2) carcinoma cell line and variably effective as anti-inflammatory and antioxidant.

Keywords: Halpophyllum tuberculatum, rutaceae, essential oil, antimicrobial, anti-inflammatory, antitumor, antioxidant, Libya

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1455 Cytotoxic Activity of Marine-derived Fungi Trichoderma Longibrachiatum Against PANC-1 Cell Lines

Authors: Elin Julianti, Marlia Singgih, Masayoshi Arai, Jianyu Lin, Masteria Yunovilsa Putra, Muhammad Azhari, Agnia S. Muharam

Abstract:

The search for a source of new medicinal compounds with anticancer activity from natural products has become important to resolve the ineffectiveness problem of pancreatic cancer therapy. Fungal marine microorganisms are prolific sources of bioactive natural products. In this present study, the ethyl acetate extract of cultured broth of Trichoderma longibrachiatum marine sponge-derived fungi exhibited selective cytotoxicity against human pancreatic carcinoma PANC-1 cells cultured under glucose-deficient conditions (IC50 = 98,4 µg/mL). The T. longibrachiatum was fermented by the static method at room temperature for 60 days. The culture broth was extracted using ethyl acetate by liquid-liquid extraction method. The liquid-liquid extraction was conducted toward the ethyl extract by using 90% MeOH-H₂O and n-|Hexane as a solvent. The extract of 90% MeOH-H₂O was fractionated by liquid extraction using by C₁₈ reversed-phase vacuum flash chromatography using mixtures of MeOH-H₂O, from 50:50 to 100:0, and 1% TFA MeOH as the eluents to yield six fractions. The fraction 2 (MeOH-H2O, 70:30) and fraction 3 (MeOH-H2O, 80:20) showed moderate cytotoxicity with IC50 value of 119.3 and 274.7 µg/mL, respectively. Fraction 4 (MeOH-H₂O, 90:10) showed the highest cytotoxicity activity with IC₅₀value of < 10 µg/mL. The chemical compounds of the fractions that are responsible for cytotoxic activity are potent for further investigation.

Keywords: cytotoxic activity, trichoderma longibrachiatum, marine-derived fungi, PANC-1 cell line

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1454 A Blending Analysis of Metaphors and Metonymies Used to Depict the Deal of the Century by Jordanian Cartoonists

Authors: Aseel Zibin, Abdel Rahman Altakhaineh

Abstract:

This study analyses 30 cartoons depicting THE DEAL OF THE CENTURY as envisaged by two Jordanian cartoonists, namely, EmadHajjaj and Osama Hajjaj. Conceptual Blending Theory (CBT) and Multimodal Metaphor Theory (MMT) are adopted as a theoretical framework to interpret the metaphors and metonymies used in the target cartoons. The results reveal that the target domain THE DEAL OF THE CENTURY was conceptualized mainly through layered metaphors that have metonymic basis and event metaphors\allegories. Specifically, 6 groups were identified: OBJECT or a situation involving OBJECTS, situations involving HUMANS\HYBRIDS of HUMANS and OBJECTS, an ANIMAL OR situation involving an ANIMAL, hybrids of WEAPONS and humans, and event metaphors used to build a story\allegory. The target domain was also depicted via event metaphors used to build a story; some of which are embedded in the Jordanian culture, while others could be perceivable cross-culturally. The results also demonstrate that the most widely used configurations to construe the metaphors was the pictorial source–verbal target in line with Lan and Zuo (2016); the motivation was probably the greater conceptual density and concreteness of visual representation since the target is better captured verbally because of its abstractness. The use of cross-modal mappings of this type was attributed to the abstractness of the target domain, THE DEAL OF THE CENTURY, which makes it more construable via verbal cues rather than visual ones. In contrast, the source domains used were mainly concrete and thus perceivable pictorially rather than verbally.

Keywords: semiotics, cognitive semantics, metaphor, culture, blending, cartoon

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1453 Study of Virus/es Threatening Large Cardamom Cultivation in Sikkim and Darjeeling Hills of Northeast India

Authors: Dharmendra Pratap

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Large Cardamom (Amomum subulatum), family Zingiberaceae is an aromatic spice crop and has rich medicinal value. Large Cardamom is as synonymous to Sikkim as Tea is to Darjeeling. Since Sikkim alone contributes up to 88% of India's large cardamom production which is the world leader by producing over 50% of the global yield. However, the production of large cardamom has declined almost to half since last two decade. The economic losses have been attributed to two viral diseases namely, chirke and Foorkey. Chirke disease is characterized by light and dark green streaks on leaves. The affected leaves exhibit streak mosaic, which gradually coalesce, turn brown and eventually dry up. Excessive sprouting and formation of bushy dwarf clumps at the base of mother plants that gradually die characterize the foorkey disease. In our surveys in Sikkim–Darjeeling hill area during 2012-14, 40-45% of plants were found to be affected with foorkey disease and 10-15% with chirke. Mechanical and aphid transmission study showed banana as an alternate host for both the disease. For molecular identification, total genomic DNA and RNA was isolated from the infected leaf tissues and subjected to Rolling circle amplification (RCA) and RT-PCR respectively. The DNA concatamers produced in the RCA reaction were monomerized by different restriction enzymes and the bands corresponding to ~1 kb genomes were purified and cloned in the respective sites. The nucleotide sequencing results revealed the association of Nanovirus with the foorkey disease of large cardamom. DNA1 showed 74% identity with Replicase gene of FBNYV, DNA2 showed 77% identity with the NSP gene of BBTV and DNA3 showed 74% identity with CP gene of BBTV. The finding suggests the presence of a new species of nanovirus associated with foorkey disease of large cardamom in Sikkim and Darjeeling hills. The details of their epidemiology and other factors would be discussed.

Keywords: RCA, nanovirus, large cardamom, molecular virology and microbiology

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1452 Secure and Privacy-Enhanced Blockchain-Based Authentication System for University User Management

Authors: Ali El Ksimi

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In today's digital academic environment, secure authentication methods are essential for managing sensitive user data, including that of students and faculty. The rise in cyber threats and data breaches has exposed the vulnerabilities of traditional authentication systems used in universities. Passwords, often the first line of defense, are particularly susceptible to hacking, phishing, and brute-force attacks. While multi-factor authentication (MFA) provides an additional layer of security, it can still be compromised and often adds complexity and inconvenience for users. As universities seek more robust security measures, blockchain technology emerges as a promising solution. Renowned for its decentralization, immutability, and transparency, blockchain has the potential to transform how user management is conducted in academic institutions. In this article, we explore a system that leverages blockchain technology specifically for managing user accounts within a university setting. The system enables the secure creation and management of accounts for different roles, such as administrators, teachers, and students. Each user is authenticated through a decentralized application (DApp) that ensures their data is securely stored and managed on the blockchain. By eliminating single points of failure and utilizing cryptographic techniques, the system enhances the security and integrity of user management processes. We will delve into the technical architecture, security benefits, and implementation considerations of this approach. By integrating blockchain into user management, we aim to address the limitations of traditional systems and pave the way for the future of digital security in education.

Keywords: blockchain, university, authentication, decentralization, cybersecurity, user management, privacy

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1451 Findings from an Access Improvement Project for Antiretroviral Therapy Uptake through Traditional Birth Attendants at Mother Theresa Hospital, Lagos, Nigeria

Authors: Daniel Afolayan, Christina Olawepo, Francis Olowookanga, Nguhemen Tingir, Olawale Fadare, John Oko

Abstract:

In Nigeria, traditional birth attendants (TBAs) can play an important role in the prevention of mother-to-child transmission of HIV. However, their role in improving access to antiretroviral therapy (ART) is unclear. Catholic Caritas Foundation of Nigeria (Caritas Nigeria) is an implementing agency supporting increased access to HIV testing and treatment services in Lagos state through health facilities including Mother Theresa Hospital. Despite intra-facility testing and community outreaches, ART uptake at Mother Theresa Hospital, Lagos was low with 6 individuals on antiretroviral drugs 3 months post-activation. This study explored improving access to ART through linkages with TBAs for ART uptake at the facility. Plan-Do-Study-Act model was used. The goal was to improve uptake of ART from 6 to 80 in 5 months (end of project year). Scanning revealed a network of 15 TBAs with potential as satellites for HIV testing. Caritas Nigeria linked the facility with 15 TBAs who were provided with HIV test kits and trained on HIV testing services for provider-initiated testing and outreaches. Weekly reports and referrals of positives were received, tracked and feedback given on testing yield. These TBAs serve individuals of various age and gender at their trado-medical centres. At the end of 5 months, HIV testing increased by 10,575 (78% from TBAs) and HIV positives obtained improved by 77 (44.2% from TBAs). 55 new individuals were enrolled and commenced on ART (61.8% from TBAs). There was a successful linkage of all clients with escort services due to incentives. Total uptake of ART was 61 (76.3% of target). Structured partnerships between TBAs and HIV care and treatment centers should be strengthened to improve access to ART.

Keywords: access improvement, antiretroviral therapy, traditional birth attendants, uptake

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1450 Development of Bioactive Medical Textiles by Immobilizing Nanoparticles at Cotton Fabric

Authors: Munir Ashraf, Shagufta Riaz

Abstract:

Personal protective equipment (PPE) and bioactive textiles are highly important for the health care of front line hospital workers, patients, and the general population to be safe from highly infectious diseases. This was even more critical in the wake of COVID-19 outbreak. Most of the medical textiles are inactive against various viruses and bacteria, hence there is a need to wash them frequently to avoid the spread of microorganisms. According to survey conducted by the world health organization, more than 500 million people get infected from hospitals, and more than 13 million died due to these hospitals’ acquired deadly diseases. The market available PPE are though effective against the penetration of pathogens and to kill bacteria but, they are not breathable and active against different viruses. Therefore, there was a great need to develop textiles that are not only effective against bacteria, fungi, and viruses but also are comfortable to the medical personnel and patients. In the present study, waterproof breathable, and biologically active textiles were developed using antiviral and antibacterial nanomaterials. These nanomaterials like TiO₂, ZnO, Cu, and Ag were immobilized at the surface of cotton fabric by using different silane coupling agents and electroless deposition that they retained their functionality even after 30 industrial laundering cycles. Afterwards, the treated fabrics were coated with a waterproof breathable film to prevent the permeation of liquid droplets, any particle or microorganisms greater than 80 nm. The developed cotton fabric was highly active against bacteria and viruses. The good durability of nanomaterials at the cotton surface after several industrial washing cycles makes this fabric an ideal candidate for bioactive textiles used in the medical field.

Keywords: antibacterial, antiviral, cotton, durable

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1449 A Qualitative Study Examining the Process of EFL Course Design from the Perspectives of Teachers

Authors: Iman Al Khalidi

Abstract:

Recently, English has become the language of globalization and technology. In turn, this has resulted in a seemingly bewildering array of influences and trends in the domain of TESOL curriculum. In light of these changes, higher education has to provide a new and more powerful kind of education. It should prepare students to be more engaged citizens, more capable to solve complex problems at work, and well prepared to lead meaningful life. In response to this, universities, colleges, schools, and departments have to work out in light of the requirements and challenges of the global and technological era. Consequently they have to focus on the adoption of contemporary curriculum which goes in line with the pedagogical shifts from teaching –centered approach to learning centered approach. Ideally, there has been noticeable emphasis on the crucial importance of developing and professionalizing teachers in order to engage them in the process of curriculum development and action research. This is a qualitative study that aims at understanding and exploring the process of designing EFL courses by teachers at the tertiary level from the perspectives of the participants in a professional context in TESOL, Department of English, a private college in Oman. It is a case study that stands on the philosophy of the qualitative approach. It employs multi methods for collecting qualitative data: semi-structured interviews with teachers, focus group discussions with students, and document analysis. The collected data have been analyzed qualitatively by adopting Miles and Huberman's Approach using procedures of reduction, coding, displaying and conclusion drawing and verification.

Keywords: course design, components of course design, case study, data analysis

Procedia PDF Downloads 538
1448 A Qualitative Study Examining the Process of Course Design from the Perspectives of Teachers

Authors: Iman Al Khalidi

Abstract:

Recently, English has become the language of globalization and technology. In turn, this has resulted in a seemingly bewildering array of influences and trends in the domain of TESOL curriculum. In light of these changes, higher education has to provide a new and more powerful kind of education. It should prepare students to be more engaged citizens, more capable to solve complex problems at work, and well prepared to lead a meaningful life. In response to this, universities, colleges, schools, and departments have to work out in light of the requirements and challenges of the global and technological era. Consequently, they have to focus on the adoption of contemporary curriculum which goes in line with the pedagogical shifts from teaching –centered approach to learning centered approach. Ideally, there has been noticeable emphasis on the crucial importance of developing and professionalizing teachers in order to engage them in the process of curriculum development and action research. This is a qualitative study that aims at understanding and exploring the process of designing EFL courses by teachers at the tertiary level from the perspectives of the participants in a professional context in TESOL, Department of English, a private college in Oman. It is a case study that stands on the philosophy of the qualitative approach. It employs multi-methods for collecting qualitative data: semi-structured interviews with teachers, focus group discussions with students, and document analysis. The collected data have been analyzed qualitatively by adopting Miles and Huberman's Approach using procedures of reduction, coding, displaying, and conclusion drawing and verification.

Keywords: course design, components of course design, case study, data analysis

Procedia PDF Downloads 438
1447 Magnetic Nano-Composite of Self-Doped Polyaniline Nanofibers for Magnetic Dispersive Micro Solid Phase Extraction Applications

Authors: Hatem I. Mokhtar, Randa A. Abd-El-Salam, Ghada M. Hadad

Abstract:

An improved nano-composite of self-doped polyaniline nanofibers and silica-coated magnetite nanoparticles were prepared and evaluated for suitability to magnetic dispersive micro solid-phase extraction. The work focused on optimization of the composite capacity to extract four fluoroquinolones (FQs) antibiotics, ciprofloxacin, enrofloxacin, danofloxacin, and difloxacin from water and improvement of composite stability towards acid and atmospheric degradation. Self-doped polyaniline nanofibers were prepared by oxidative co-polymerization of aniline with anthranilic acid. Magnetite nanopariticles were prepared by alkaline co-precipitation and coated with silica by silicate hydrolysis on magnetite nanoparticles surface at pH 6.5. The composite was formed by self-assembly by mixing self-doped polyaniline nanofibers with silica-coated magnetite nanoparticles dispersions in ethanol. The composite structure was confirmed by transmission electron microscopy (TEM). Self-doped polyaniline nanofibers and magnetite chemical structures were confirmed by FT-IR while silica coating of the magnetite was confirmed by Energy Dispersion X-ray Spectroscopy (EDS). Improved stability of the composite magnetic component was evidenced by resistance to degrade in 2N HCl solution. The adsorption capacity of self-doped polyaniline nanofibers based composite was higher than previously reported corresponding composite prepared from polyaniline nanofibers instead of self-doped polyaniline nanofibers. Adsorption-pH profile for the studied FQs on the prepared composite revealed that the best pH for adsorption was in range of 6.5 to 7. Best extraction recovery values were obtained at pH 7 using phosphate buffer. The best solvent for FQs desorption was found to be 0.1N HCl in methanol:water (8:2; v/v) mixture. 20 mL of Spiked water sample with studied FQs were preconcentrated using 4.8 mg of composite and resulting extracts were analysed by HPLC-UV method. The prepared composite represented a suitable adsorbent phase for magnetic dispersive micro-solid phase application.

Keywords: fluoroquinolones, magnetic dispersive micro extraction, nano-composite, self-doped polyaniline nanofibers

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1446 The Relationship between Mothers’ Attachment Style, Mindful Parenting and Perception of the Child

Authors: Brigitta Szabo, Miklosi Monika

Abstract:

Background/Aims: In early childhood, the context of development is the caregiver-child relationship. Maternal attachment style plays a major role in the intergenerational transmission of psychopathology. The aim of this study was to explore the relationship between the mothers’ attachment style, mindful parenting, and perception of the child. Method: Data was collected from 144 non-clinical mothers who have a child below the age of 3 years. Mothers completed self-report questionnaires, including the following scales: a demographic questionnaire, Attachment Style Questionnaire (ASQ), Interpersonal Mindfulness in Parenting Scale (IMP), and the Mothers’ Object Relations Scale (MORS-SF). K-means cluster analysis was used to identify the mothers’ attachment styles. Mediation analyses with Mothers’ Object Relations Scale (MORS-SF) positive emotions and dominance subscales as dependent variables, mothers’ attachment style (ASQ) as an independent variable, and mindful parenting (IMP) as a mediator were conducted. Results: Four attachment styles (secure, preoccupied, fearful, dismissing) were identified. The relationship between mothers’ attachment style and mindful parenting was significant (R2 = .51; F(4,139) = 36.60; p < .001). Compared to the secure attachment style as a reference group, both preoccupied and dismissing styles were related to lower levels of mindful parenting; however, this relationship was the strongest in case of fearful style. In mediation analysis the direct effects of mothers’ attachment style on the perception of the child were not significant (MORS positive emotions: R2= .29; F(5,138) = 11.22; p < .001; MORS dominance: R2= .39 F(5,138) = 17.54, p < .001). However, indirect effects through mindful parenting were significant; higher levels of mindful parenting were associated with higher levels of MORS positive emotions and lower levels of MORS dominance. Conclusions: These findings suggest that attachment styles are related to the perception of the child through mindful parenting. Mindfulness-based parenting training might be useful in case of attachment-related problems to improve the parent-child relationship.

Keywords: mindfulness, mindful parenting, attachement, perception

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1445 A Study to Explore the Views of Students regarding E-Learning as an Instructional Tool at University Level

Authors: Zafar Iqbal

Abstract:

This study involved students of 6th semester enrolled in a Bachelor of Computer Science Program at university level. In this era of science and technology, e-learning can be helpful for grassroots in providing them access to education tenant in less developed areas. It is a potential substitute of face-to-face teaching being used in different countries. The purpose of the study was to explore the views of students about e-learning (Facebook) as an instructional tool. By using purposive sampling technique an intact class of 30 students included both male and female were selected where e-learning was used as an instructional tool. The views of students were explored through qualitative approach by using focus group interviews. The approach was helpful to develop comprehensive understanding of students’ views towards e- learning. In addition, probing questions were also asked and recorded. Data was transcribed, generated nodes and then coded text against these nodes. For this purpose and further analysis, NVivo 10 software was used. Themes were generated and tangibly presented through cluster analysis. Findings were interesting and provide sufficient evidence that face book is a subsequent e-learning source for students of higher education. Students acknowledged it as best source of learning and it was aligned with their academic and social behavior. It was not time specific and therefore, feasible for students who work day time and can get on line access to the material when they got free time. There were some distracters (time wasters) reported by the students but can be minimized by little effort. In short, e-learning is need of the day and potential learning source for every individual who have access to internet living at any part of the globe.

Keywords: e-learning, facebook, instructional tool, higher education

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1444 Jelly and Beans: Appropriate Use of Ultrasound in Acute Kidney Injury

Authors: Raja Ezman Raja Shariff

Abstract:

Acute kidney injury (AKI) is commonly seen in inpatients, and places a great cost on the NHS and patients. Timely and appropriate management is both nephron sparing and potentially life-saving. Ultrasound scanning (USS) is a well-recognised method for stratifying patients. Subsequently, the NICE AKI guidance has defined groups in whom scanning is recommended within 6 hours of request (pyonephrosis), within 24 hours (obstruction/cause unknown), and in whom routine scanning isn't recommended (cause for AKI identified). The audit looks into whether Stockport NHS Trust USS practice was in line with such recommendations. The audit evaluated 92 patients with AKI who had USS, between 01/01/14 to 30/04/14. Data collection was divided into 2 parts. Firstly, radiology request cards and the online imaging software (PACS) were evaluated. Then, the electronic case notes (ADVANTIS) was evaluated further. Based on request cards, 10% of requests were for pyonephrosis. Only 33% were scanned within 6hours and a further 33% within 24hours. 75% were requested for possible obstructions and unknown cause collectively. Of those due to possible obstruction, 71% of patients were scanned within 24 hours. Of those with unknown cause, 50% were scanned within 24 hours. 15% of requests had a cause declared and so potentially did not require scanning. Evaluation of the patients’ notes suggested further interesting findings. Firstly, potentially 39% of patients had a known cause for AKI, therefore, did not need USS. Subsequently, the cohort of unknown cause and possible obstruction was collectively reduced to 45%. Alarmingly the patient cohort with possible pyonephrosis went up to 16%, suggesting an under-recognition of this life-threatening condition. We plan to highlight these findings within our institution and make changes to encourage more appropriate requesting and timely scanning. Time will tell if we manage to save or increase our costs in this cost-conscious NHS. Patient benefits, though, seem to be guaranteed.

Keywords: AKI, ARF, kidney, renal

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1443 Chikungunya Virus Detection Utilizing an Origami Based Electrochemical Paper Analytical Device

Authors: Pradakshina Sharma, Jagriti Narang

Abstract:

Due to the critical significance in the early identification of infectious diseases, electrochemical sensors have garnered considerable interest. Here, we develop a detection platform for the chikungunya virus by rationally implementing the extremely high charge-transfer efficiency of a ternary nanocomposite of graphene oxide, silver, and gold (G/Ag/Au) (CHIKV). Because paper is an inexpensive substrate and can be produced in large quantities, the use of electrochemical paper analytical device (EPAD) origami further enhances the sensor's appealing qualities. A cost-effective platform for point-of-care diagnostics is provided by paper-based testing. These types of sensors are referred to as eco-designed analytical tools due to their efficient production, usage of the eco-friendly substrate, and potential to reduce waste management after measuring by incinerating the sensor. In this research, the paper's foldability property has been used to develop and create 3D multifaceted biosensors that can specifically detect the CHIKVX-ray diffraction, scanning electron microscopy, UV-vis spectroscopy, and transmission electron microscopy (TEM) were used to characterize the produced nanoparticles. In this work, aptamers are used since they are thought to be a unique and sensitive tool for use in rapid diagnostic methods. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV), which were both validated with a potentiostat, were used to measure the analytical response of the biosensor. The target CHIKV antigen was hybridized with using the aptamer-modified electrode as a signal modulation platform, and its presence was determined by a decline in the current produced by its interaction with an anionic mediator, Methylene Blue (MB). Additionally, a detection limit of 1ng/ml and a broad linear range of 1ng/ml-10µg/ml for the CHIKV antigen were reported.

Keywords: biosensors, ePAD, arboviral infections, point of care

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1442 Effect of Different Levels of Distillery Yeast Sludge on Immune Level, Egg Quality and Performance of Layers as a Substitute for Soybean Meal

Authors: Rana Bilal, Faiz-Ul-Hassan, Moazzam Jameel

Abstract:

There is a dire need to replace high-cost protein with more economical protein to overcome animal protein shortage in developing nations especially countries like Pakistan. In conjunction with these efforts, the current study was planned to evaluate the effects of various dried distillery yeast sludge (DYS) levels on the immune level, egg quality, and performance of layers by replacing soybean meal. The study was designed with two hundred layers of Hy-Line variety. Distillery yeast sludge was dried and ground for 2 mm mesh size and after this proximate and mineral analysis was determined. Five isocaloric and isonitrogeneous feeds were given containing C (control), 5, 10, 15, 20% distillery yeast sludge by replacing soybean meal. The trial was performed in the completely randomized design with five treatments, 4 replicates and 10 hen per replicate. Results demonstrated that feed intake, egg production, feed conversion ratio decreased (P < 0.05) with the increased dietary DYS. However, statistically significant decrease (P < 0.05) was found in hens having DYS20 diet than control. Layers on Diets C, DYS5 and DYS10 exerted a higher immune level than DYS15 and DYS20 diets. Egg weight, eggshell weight, eggshell thickness, egg albumen height as well as haugh unit score were affected significantly by the increased level of DYS. In general, results of this study demonstrated that inclusion of DYS up to 10% showed no adverse effects on health and performance of layers.

Keywords: egg quality, immunity, layers, performance

Procedia PDF Downloads 224
1441 Microwave Assisted Rapid Synthesis of Nano-Binder from Renewable Resource and Their Application in Textile Printing

Authors: K. Haggag, N. S. Elshemy

Abstract:

Due to limited fossil resource and an increased need for environmentally friendly, sustainable technologies, the importance of using renewable feed stocks in textile industry area will increase in the decades to come. This research highlights some of the perspectives in this area. Alkyd resins for high characterization and reactive properties, completely based on commercially available renewable resources (sunflower and/or soybean oil) were prepared and characterized. In this work, we present results on the synthesis of various alkyd resins according to the alcoholysis – polyesterification process under different preparation conditions using a microwave synthesis as energy source to determine suitable reaction conditions. Effects of polymerization parameters, such as catalyst ratio, reaction temperature and microwave power level have been studied. The prepared binder was characterized via FT-IR, scanning electron microscope (SEM) and transmission electron microscope (TEM), in addition to acid value (AV), iodine value (IV), water absorbance, weight loss, and glass transition temperature. The prepared binder showed high performance physico-mechanical properties. TEM analysis showed that the polymer latex nanoparticle within range of 20–200 nm. The study involved the application of the prepared alkyd resins as binder for pigment printing process onto cotton fabric by using a flat screen technique and the prints were dried and thermal cured. The optimum curing conditions were determined, color strength and fastness properties of pigment printed areas to light, washing, perspiration and crocking were evaluated. The rheological properties and apparent viscosity of prepared binders were measured in addition roughness of the prints was also determined.

Keywords: nano-binder, microwave heating, renewable resource, alkyd resins, sunflower oil, soybean oil

Procedia PDF Downloads 370
1440 A Three-Dimensional (3D) Numerical Study of Roofs Shape Impact on Air Quality in Urban Street Canyons with Tree Planting

Authors: Bouabdellah Abed, Mohamed Bouzit, Lakhdar Bouarbi

Abstract:

The objective of this study is to investigate numerically the effect of roof shaped on wind flow and pollutant dispersion in a street canyon with one row of trees of pore volume, Pvol = 96%. A three-dimensional computational fluid dynamics (CFD) model for evaluating air flow and pollutant dispersion within an urban street canyon using Reynolds-averaged Navier–Stokes (RANS) equations and the k-Epsilon EARSM turbulence model as close of the equation system. The numerical model is performed with ANSYS-CFX code. Vehicle emissions were simulated as double line sources along the street. The numerical model was validated against the wind tunnel experiment. Having established this, the wind flow and pollutant dispersion in urban street canyons of six roof shapes are simulated. The numerical simulation agrees reasonably with the wind tunnel data. The results obtained in this work, indicate that the flow in 3D domain is more complicated, this complexity is increased with presence of tree and variability of the roof shapes. The results also indicated that the largest pollutant concentration level for two walls (leeward and windward wall) is observed with the upwind wedge-shaped roof. But the smallest pollutant concentration level is observed with the dome roof-shaped. The results also indicated that the corners eddies provide additional ventilation and lead to lower traffic pollutant concentrations at the street canyon ends.

Keywords: street canyon, pollutant dispersion, trees, building configuration, numerical simulation, k-Epsilon EARSM

Procedia PDF Downloads 354
1439 Federal Center for Technological Education of Minas Gerais (CEFET-MG)

Authors: María González Alriols, Itziar Egües, María A. Andrés, Mirari Antxustegi

Abstract:

Several collaborative learning proposals were prepared to be applied in the laboratory sessions of chemistry in the first course of engineering studies. The aim was to engage the students from the beginning and to avoid absenteeism as well as to reach a more homogeneous level in the class. The students, divided into small groups of four or five mates, were asked to do an exercise before having the practical session in the lab. Precisely, each one of the groups was asked to study the theoretical fundamentals and the practical aspects of one lab session and to prepare a didactical video with this content, including the materials, equipment and reactants required, and the detailed experimental procedure. Furthermore, they should include the performance of the experiment step by step, indicating the faced difficulties and the obtained results and conclusions. After watching the video of this precise activity, the other groups of students would go to the lab to put into practice the session following the commands explained in the video. The evaluation of the video activity that is worth the 50% of the total mark of the laboratory sessions, is done depending on the success that the other groups of students had while doing the practical session that was explained in the video. This means that the successful transmission of knowledge to the rest of the mates in the class through the video was compulsory to pass the practical sessions and the subject. The other 50% of the mark depended on the understanding of the other students’ explanations and the success in the corresponding practical sessions. The experience was found to be very positive, as the engagement level was considerably higher, the absenteeism lower and the attitude in the laboratory much more responsible. The materials, reactants and equipment were used carefully, and no incidents were registered. Furthermore, the fact of having peer experts was useful to encourage critical thinking in a more relaxed way, with the teacher figure in a secondary position. Finally, the academic achievements were satisfactory as well, with a high percentage of students over the level required for passing the subject.

Keywords: collaborative learning, engineering instruction, chemistry, laboratory sessions

Procedia PDF Downloads 160