Search results for: chemical precipitation technique
10303 Evaluation of Transfer Capability Considering Uncertainties of System Operating Condition and System Cascading Collapse
Authors: Nur Ashida Salim, Muhammad Murtadha Othman, Ismail Musirin, Mohd Salleh Serwan
Abstract:
Over the past few decades, the power system industry in many developing and developed countries has gone through a restructuring process of the industry where they are moving towards a deregulated power industry. This situation will lead to competition among the generation and distribution companies to achieve a certain objective which is to provide quality and efficient production of electric energy, which will reduce the price of electricity. Therefore it is important to obtain an accurate value of the Available Transfer Capability (ATC) and Transmission Reliability Margin (TRM) in order to ensure the effective power transfer between areas during the occurrence of uncertainties in the system. In this paper, the TRM and ATC is determined by taking into consideration the uncertainties of the system operating condition and system cascading collapse by applying the bootstrap technique. A case study of the IEEE RTS-79 is employed to verify the robustness of the technique proposed in the determination of TRM and ATC.Keywords: available transfer capability, bootstrap technique, cascading collapse, transmission reliability margin
Procedia PDF Downloads 40810302 Study of Chemical Compounds of Garlic
Authors: Bazaraliyeva Aigerim Bakytzhanovna, Turgumbayeva Aknur Amanbekovna
Abstract:
The phytosubstance from garlic was obtained by extraction with liquid carbon dioxide under critical conditions. Methods of processing raw materials are proposed, and the chemical composition of garlic is studied by gas chromatography and mass spectrometry. The garlic extract's composition was determined using gas chromatography (GC) and gas chromatography-mass spectrophotometry (GC-MS). The phytosubstance had 54 constituents. The extract included the following main compounds: Manool (39.56%), Viridifrolol (7%), Podocarpa-1,8,11,13-tetraen-3-one, 14-isopropyl-1,13-dimethoxy- 5,15 percent, (+)-2-Bornanone (4.29%), Thujone (3.49%), Linolic acid ethyl ester (3.41%), and 12-O-Methylcarn.Keywords: allium sativum, bioactive compounds of garlic, carbon dioxide extraction of garlic, GS-MS method
Procedia PDF Downloads 8010301 Performance of Segmented Thermoelectric Materials Using 'Open-Short Circuit' Technique under Different Polarity
Authors: N. H. S. Mustafa, N. M. Yatim
Abstract:
Thermoelectric materials arrange in segmented design could increase the conversion of heat to electricity performance. This is due to the properties of materials that perform peak at narrow temperature range. Performance of the materials determines by dimensionless figure-of-merit, ZT which consist of thermoelectric properties namely Seebeck coefficient, electrical resistivity, and thermal conductivity. Since different materials were arrange in segmented, determination of ZT cannot be measured using the conventional approach. Therefore, this research used 'open-short circuit' technique to measure the segmented performance. Segmented thermoelectric materials consist of bismuth telluride, and lead telluride was segmented together under cold press technique. The results show thermoelectric properties measured is comparable with calculated based on commercially available of individual material. Performances of segmented sample under different polarity also indicate dependability of material with position and temperature. Segmented materials successfully measured under real condition and optimization of the segmented can be designed from the study of polarity change.Keywords: thermoelectric, segmented, ZT, polarity, performance
Procedia PDF Downloads 20210300 Spinochromes: Kairomones Involved in the Symbiosis between the Shrimp Tuleariocaris holthuisi and Echinometra mathaei
Authors: Lola Brasseur, Guillaume Caulier, Marie Demeyer, Pascal Gerbaux, Igor Eeckhaut
Abstract:
Seawater being an ideal dispersing agent, chemical communication stays predominant in marine ecosystems. However, if many molecules acting in chemical heterospecific communication have already been well described in terrestrial ecosystems, only three of these molecules were identified in marine ecosystems. Echinoderms and their symbiotic organisms constitute very good models to study heterospecific chemical communication because each class synthesizes a specific type of molecules and symbioses with echinoderms as hosts are very usual. In this study, the chemical communication that allows the commensal shrimps Tuleariocaris holthuisi Hipeau-Jacquotte, 1965 to live with their host Echinometra mathaei (Blainville, 1825) was investigated. The chemoreception of the shrimp was characterized using olfactometers and it was demonstrated that hosts and synthetic hydroxynaphthoquinones are attractive to the symbiotic shrimps. Hydroxynaphthoquinonic pigments also known as spinochromes are by the way synthesized by sea urchin and involved in all probability in a lot of mechanisms. To our knowledge, this study is the first highlighting the ecological function of naphthoquinones as kairomones. Chemical extractions were also performed on sea urchins in order to analyze and identify their specific hydroxynaphthoquinones using HPLC-ESI-MS. Accurate mass identification and elemental composition have been performed on various organs (gonads, coelomic liquid, digestive system and test) in different morphotypes of Echinometra mathaei for a better understanding of the molecular diversity of these semiochemicals. Moreover, some experiments were performed to investigate the dependence of T. holthuisi for their host. First, the analyses showed that the molecules involved in shrimp pigmentation are the same that the ones involved in E. mathaei, suggesting a potential feeding on the host. Secondly, a substantial shrimp depigmentation and an increase of the mortality rate were demonstrated after the symbionts-host separation which could mean a potential implication of spinochromes in the shrimp metabolism.Keywords: crustacean, sea urchin, spinochrome, symbiosis
Procedia PDF Downloads 19110299 Wall Shear Stress Under an Impinging Planar Jet Using the Razor Blade Technique
Authors: A. Ritcey, J. R. Mcdermid, S. Ziada
Abstract:
Wall shear stress was experimentally measured under a planar impinging air jet as a function of jet Reynolds number (Rejet = 5000, 8000, 11000) and different normalized impingement distances (H/D = 4, 6, 8, 10, 12) using the razor blade technique to complete a parametric study. The wall pressure, wall pressure gradient, and wall shear stress information were obtained.Keywords: experimental fluid mechanics, impinging planar jets, skin friction factor, wall shear stress
Procedia PDF Downloads 32210298 Synthesis of Silver Nanoparticles by Different Types of Plants
Authors: Khamael Abualnaja, Hala M. Abo-Dief
Abstract:
Silver nanoparticles (AgNPs) are the subject of important recent interest, present in a large range of applications such as electronics, catalysis, chemistry, energy, and medicine. Metallic nanoparticles are traditionally synthesized by wet chemical techniques, where the chemicals used are quite often toxic and flammable. In this work, we describe an effective and environmental-friendly technique of green synthesis of silver nanoparticles. Silver nanoparticles (AgNPs) synthesized using silver nitrate solution and the extract of mint, basil, orange peel and Tangerines peel which used as reducing agents. Silver Nanoparticles were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and UV–Vis absorption spectroscopy. SEM analysis showed the average particle size of mint, basil, orange peel, Tangerines peel are 30, 20, 12, 10 nm respectively. This is for the first time that any plant extract was used for the synthesis of nanoparticles.Keywords: silver nanoparticles, green synthesis, scanning electron microscopy, plants
Procedia PDF Downloads 25810297 Rooting Out Breast Cancer by Repressing ER Gene Expression: Correlating Bioactivity of Pomegranate Rind with Chemical Constituents Identified by HPLC-MS/MS
Authors: Alaa M. M. Badr Eldin, Marwa I. Ezzat, Mohammed S. Sedeek, Manal S. Afifi, Omar M. Sabry
Abstract:
Cytotoxic activity of the total methanol extract against breast cancer cell line MCF-7 was amazing IC50 at 54 ug/ml. 130 polyphenolic compounds were tentatively identified in pomegranate peel (Punica granatum L.) methanol extract using HPLC-MS/MS technique. The antiestrogenic activity of the polyphenolic constituents found in pomegranate extract was confirmed experimentally in-vitro and by the in-silico molecular docking using gallagic acid, ellagic acid, and Punicalagin as these are considered model compounds confirmed in pomegranate peel extract. The methanolic extract was found to suppress ER, TGF-β, and NF-kB in-vitro gene expression strongly, and that was verified by qPCR and Western Blot gel electrophoresis techniques.Keywords: HPLC-MS/MS, pomegranate, breast cancer, ovarian cancer, ER, TGF-β, NF-kB
Procedia PDF Downloads 10210296 An Empirical Approach to NO2 Gas Sensing Properties of Carbon Films Fabricated by Arc Discharge Methane Decomposition Technique
Authors: Elnaz Akbari, Zolkafle Buntat
Abstract:
Today, the use of carbon-based materials such as graphene, carbon nanotubes, etc. in various applications is being extensively studied by researchers in the field. One of such applications is using them in gas sensors. While analytical investigations on the physical and chemical properties of carbon nanomaterials are the focal points in the studies, the need for experimental measurements on various physical characteristics of these materials is deeply felt. In this work, a set of experiments has been conducted using arc discharge Methane decomposition attempting to obtain carbonaceous materials (C-strands) formed between graphite electrodes. The current-voltage (I-V) characteristics of the fabricated C-strands have been investigated in the presence and absence of two different gases, NO2 and CO2. The results reveal that the current passing through the carbon films increases when the concentrations of gases are increased from 200 to 800 ppm. This phenomenon is a result of conductance changes and can be employed in sensing applications such as gas sensors.Keywords: carbonaceous materials, gas sensing, methane arc discharge decomposition, I-V characteristics
Procedia PDF Downloads 21610295 Failure Analysis of Recoiler Mandrel Shaft Used for Coiling of Rolled Steel Sheet
Authors: Sachin Pawar, Suman Patra, Goutam Mukhopadhyay
Abstract:
The primary function of a shaft is to transfer power. The shaft can be cast or forged and then machined to the final shape. Manufacturing of ~5 m length and 0.6 m diameter shaft is very critical. More difficult is to maintain its straightness during heat treatment and machining operations, which involve thermal and mechanical loads, respectively. During the machining operation of a such forged mandrel shaft, a deflection of 3-4mm was observed. To remove this deflection shaft was pressed at both ends which led to the development of cracks in it. To investigate the root cause of the deflection and cracking, the sample was cut from the failed shaft. Possible causes were identified with the help of a cause and effect diagram. Chemical composition analysis, microstructural analysis, and hardness measurement were done to confirm whether the shaft meets the required specifications or not. Chemical composition analysis confirmed that the material grade was 42CrMo4. Microstructural analysis revealed the presence of untempered martensite, indicating improper heat treatment. Due to this, ductility and impact toughness values were considerably lower than the specification of the mentioned grade. Residual stress measurement of one more bent shaft manufactured by a similar route was done by portable X-ray diffraction(XRD) technique. For better understanding, measurements were done at twelve different locations along the length of the shaft. The occurrence of a high amount of undesirable tensile residual stresses close to the Ultimate Tensile Strength(UTS) of the material was observed. Untempered martensitic structure, lower ductility, lower impact strength, and presence of a high amount of residual stresses all confirmed the improper tempering heat treatment of the shaft. Tempering relieves the residual stresses. Based on the findings of this study, stress-relieving heat treatment was done to remove the residual stresses and deflection in the shaft successfully.Keywords: residual stress, mandrel shaft, untempered martensite, portable XRD
Procedia PDF Downloads 11210294 LIFirr with an Indicator of Microbial Activity in Paraffinic Oil
Authors: M. P. Casiraghi, C. M. Quintella, P. Almeida
Abstract:
Paraffinic oils were submitted to microbial action. The microorganisms consisted of bacteria of the genera Pseudomonas sp and Bacillus lincheniforms. The alterations in interfacial tension were determined using a tensometer and applying the hanging drop technique at room temperature (299 K ±275 K). The alteration in the constitution of the paraffins was evaluated by means of gas chromatography. The microbial activity was observed to reduce interfacial tension by 54 to 78%, as well as consuming the paraffins C19 to C29 and producing paraffins C36 to C44. The LIFirr technique made it possible to determine the microbial action quickly.Keywords: paraffins, biosurfactants, LIFirr, microbial activity
Procedia PDF Downloads 52510293 Molecular Diagnosis of Influenza Strains Was Carried Out on Patients of the Social Security Clinic in Karaj Using the RT-PCR Technique
Authors: A. Ferasat, S. Rostampour Yasouri
Abstract:
Seasonal flu is a highly contagious infection caused by influenza viruses. These viruses undergo genetic changes that result in new epidemics across the globe. Medical attention is crucial in severe cases, particularly for the elderly, frail, and those with chronic illnesses, as their immune systems are often weaker. The purpose of this study was to detect new subtypes of the influenza A virus rapidly using a specific RT-PCR method based on the HA gene (hemagglutinin). In the winter and spring of 2022_2023, 120 embryonated egg samples were cultured, suspected of seasonal influenza. RNA synthesis, followed by cDNA synthesis, was performed. Finally, the PCR technique was applied using a pair of specific primers designed based on the HA gene. The PCR product was identified after purification, and the nucleotide sequence of purified PCR products was compared with the sequences in the gene bank. The results showed a high similarity between the sequence of the positive samples isolated from the patients and the sequence of the new strains isolated in recent years. This RT-PCR technique is entirely specific in this study, enabling the detection and multiplication of influenza and its subspecies from clinical samples. The RT-PCR technique based on the HA gene, along with sequencing, is a fast, specific, and sensitive diagnostic method for those infected with influenza viruses and its new subtypes. Rapid molecular diagnosis of influenza is essential for suspected people to control and prevent the spread of the disease to others. It also prevents the occurrence of secondary (sometimes fatal) pneumonia that results from influenza and pathogenic bacteria. The critical role of rapid diagnosis of new strains of influenza is to prepare a drug vaccine against the latest viruses that did not exist in the community last year and are entirely new viruses.Keywords: influenza, molecular diagnosis, patients, RT-PCR technique
Procedia PDF Downloads 7410292 Phishing Detection: Comparison between Uniform Resource Locator and Content-Based Detection
Authors: Nuur Ezaini Akmar Ismail, Norbazilah Rahim, Norul Huda Md Rasdi, Maslina Daud
Abstract:
A web application is the most targeted by the attacker because the web application is accessible by the end users. It has become more advantageous to the attacker since not all the end users aware of what kind of sensitive data already leaked by them through the Internet especially via social network in shake on ‘sharing’. The attacker can use this information such as personal details, a favourite of artists, a favourite of actors or actress, music, politics, and medical records to customize phishing attack thus trick the user to click on malware-laced attachments. The Phishing attack is one of the most popular attacks for social engineering technique against web applications. There are several methods to detect phishing websites such as Blacklist/Whitelist based detection, heuristic-based, and visual similarity-based detection. This paper illustrated a comparison between the heuristic-based technique using features of a uniform resource locator (URL) and visual similarity-based detection techniques that compares the content of a suspected phishing page with the legitimate one in order to detect new phishing sites based on the paper reviewed from the past few years. The comparison focuses on three indicators which are false positive and negative, accuracy of the method, and time consumed to detect phishing website.Keywords: heuristic-based technique, phishing detection, social engineering and visual similarity-based technique
Procedia PDF Downloads 17710291 Gis-Based Water Pollution Assesment of Buriganga River, Bangladesh
Authors: Nur-E-Jannat Tinu
Abstract:
Water is absolutely vital not only for the survival of human beings but also for plants, animals, and all other living organisms. Water bodies, such as lakes, rivers, ponds, and estuaries, are the source of water supply in domestic, industrial, agriculture, and aquaculture purposes. The Buriganga River flows through the south and west of Dhaka city. The water quality of this river has become a matter of concern due to anthropogenic intervention of vital pollutants such as industrial effluents, urban sewage, and solid wastes in this area. Buriganga River is at risk to contamination from untreated municipal wastes, industrial discharges, runoff from organic and inorganic fertilizers, pesticides, insecticides, and oil emission around the river. The residential and commercial establishments along the river discharge wastewater either directly into the river or through drains and canals into the river. However, several regulatory measures and policies have been enforced by the Government to protect the river Buriganga from pollution, in most cases to no affect. Water quality assessment reveals that the water is also not appropriate for irrigation purposes. The physical parameters (pH, TDS, EC, Temperature, DO, COD, BOD) indicated that the water is too poor to be useable for agricultural, drinking, or other purposes. Chemical concentrations showed significant seasonal variations with high-level concentrations during the monsoon season, presumably due to extreme seasonal surface runoff. A comparative study of Electrical Conductivity (EC) and Total Dissolved Solids (TDS) indicated a considerable increase over the last five years A change in trend was observed from 2020 June-July, probably due to monsoon and post-monsoon. EC values decreased from 775 to 665 mmho/cm during this period. DO increased significantly from the mid-post-monsoon months to the early monsoon period. The pH value of river water is strongly alkaline, ranging between 6.5 and 7.79. This indicates that ecological organic compounds cause the water to become alkaline after the monsoon and monsoon seasons. As the water pollution level is very high, an effective remediation and pollution control plan should be considered.Keywords: precipitation, spatial distribution, effluent, remediation
Procedia PDF Downloads 14010290 The Transport of Radical Species to Single and Double Strand Breaks in the Liver’s DNA Molecule by a Hybrid Method of Type Monte Carlo - Diffusion Equation
Abstract:
The therapeutic utility of certain Auger emitters such as iodine-125 depends on their position within the cell nucleus . Or diagnostically, and to maintain as low as possible cell damage, it is preferable to have radionuclide localized outside the cell or at least the core. One solution to this problem is to consider markers capable of conveying anticancer drugs to the tumor site regardless of their location within the human body. The objective of this study is to simulate the impact of a complex such as bleomycin on single and double strand breaks in the DNA molecule. Indeed, this simulation consists of the following transactions: - Construction of BLM -Fe- DNA complex. - Simulation of the electron’s transport from the metastable state excitation of Fe 57 by the Monte Carlo method. - Treatment of chemical reactions in the considered environment by the diffusion equation. For physical, physico-chemical and finally chemical steps, the geometry of the complex is considered as a sphere of 50 nm centered on the binding site , and the mathematical method used is called step by step based on Monte Carlo codes.Keywords: concentration, yield, radical species, bleomycin, excitation, DNA
Procedia PDF Downloads 45710289 Improving the Corrosion Resistance of Magnesium by Application of TiO₂-MgO Coatings
Authors: Eric Noe Hernandez Rodriguez, Cristian Esneider Penuela Cruz
Abstract:
Magnesium is a biocompatible and biodegradable material that has gained increased interest for application in resorbable orthopedic implants. However, to date, much research is being conducted to overcome the main disadvantage: its low corrosion resistance. In this work, we report our findings on the development and application of TiO₂-MgO coatings to improve and modulate the corrosion resistance of magnesium pieces. The plasma electrolytic oxidation (PEO) technique was employed to obtain the TiO₂-MgO coatings. The effect of the experimental parameters on the modulation of the TiO₂:MgO ratio was investigated. The most critical parameters were the chemical composition of the precursor electrolytic solution and the current density. According to scanning electron microscopy (SEM) observations, the coatings were porous; however, they become more compact as the current density increases. XRD measurements showed that the coatings are formed by a composite consisting of TiO₂ and MgO oxides, whose ratio can be changed by the experimental conditions. TiO₂ had the anatase crystalline structure, while the MgO had the FCC crystalline structure. The corrosion resistance was evaluated through the corrosion current (Icorr) measured at room temperature by the polarization technique (Tafel). For doing it, Hank's solution was used in order to simulate the body fluids. Also, immersion tests were conducted. Tafel curves showed an improvement of the corrosion resistance at some coated magnesium pieces in contrast to control pieces (uncoated). Corrosion currents were lower, and the corrosion potential changed to positive values. It was observed that the experimental parameters allowed to modulate the protective capacity of the coatings by changing the TiO₂:MgO ratio. Coatings with a higher content of TiO₂ (measured by energy dispersive spectroscopy) showed higher corrosion resistance. Results showed that TiO₂-MgO coatings can be successfully applied to improve the corrosion resistance of Mg pieces in simulated body fluid; even more, the corrosion resistance can be tuned by changing the TiO₂:MgO ratio.Keywords: biomaterials, PEO, corrosion resistance, magnesium
Procedia PDF Downloads 10410288 Electrochemical Coagulation of Synthetic Textile Dye Wastewater
Authors: H. B. Rekha, Usha N. Murthy, Prashanth, Ashoka
Abstract:
Dyes are manufactured to have high chemical resistance because they are normally species, very difficult to degrade (reactive dyes). It damages flora and fauna. Furthermore, coloured components are highly hazardous. So removal of dyes becomes a challenge for both textile industry and water treatment facility. Dyeing wastewater is usually treated by conventional methods such as biological oxidation and adsorption but nowadays them becoming in-adequate because of large variability of composition of waste water. In the present investigation, mild steel electrodes of varying surface area were used for treatment of synthetic textile dye. It appears that electro-chemical coagulation could be very effective in removing coloured from wastewater; it could also be used to remove other parameters like chlorides, COD, and solids to some extent. In the present study, coloured removal up to 99% was obtained for surface area of mild steel electrode of 80 cm2 and 96% of surface area of mild steel electrode of 50 cm2. The findings from this study could be used to improve the design of electro-chemical treatment systems and modify existing systems to improve efficiency.Keywords: electrochemical coagulation, mild steel, colour, environmental engineering
Procedia PDF Downloads 30710287 Chemical Constituents and Biological Evaluation of Leaves Essential Oils of Vitex agnus-castus L. Growing in the Southern-West Algeria
Authors: Abdallah Habbab, Khaled Sekkoum, Nasser Belboukhari
Abstract:
Objective: This study is designed to examine the chemical composition, antioxidant and antibacterial activities of the essential oil extracted from leaves of Vitex agnus-castus. Methods: The essential oils of dry leaves of Vitex agnus-castus L. were obtained by hydro-distillation, afforded oil in the yield of 5.5% and their volatile constituents were identified by GC/MS. Antioxidant activity of the sample was determined by test system DPPH. Antifungal activity was tested against three fungal strains (Aspergillus flavus, Penicillium escpansum and Aspergillus ochraceus) by direct contact method. Results: Forty-three compounds were identified, representing 98.02% of the oil. Major components of the oil were 1,8-cineole (18.27 %), caryophyllene (8.60 %), N-(M-fluorophenyl)-maleimide (6.30 %), (+)-epi-bicyclosesquiphellandrene (6.00 %), terpinen-4-ol (5.57 %), pyrrolo (3,2,1-jk) carbazole (5.43 %), caryophyllene oxide (4.79 %), and phenol (4.09 %). Conclusion: The chemical constituents in the essential oil from the locally grown Vitex agnus-castus were identified. Therefore, the essential oil of Vitex agnus-castus is an active candidate which would be used as antioxidant, or antifungal agent in new drugs preparation for therapy of diseases.Keywords: Vitex agnus-castus, essential oil, GC/MS, DPPH, 1, 8-cineole
Procedia PDF Downloads 46310286 The Effectiveness of Energy Index Technique in Bearing Condition Monitoring
Authors: Faisal Alshammari, Abdulmajid Addali, Mosab Alrashed, Taihiret Alhashan
Abstract:
The application of acoustic emission techniques is gaining popularity, as it can monitor the condition of gears and bearings and detect early symptoms of a defect in the form of pitting, wear, and flaking of surfaces. Early detection of these defects is essential as it helps to avoid major failures and the associated catastrophic consequences. Signal processing techniques are required for early defect detection – in this article, a time domain technique called the Energy Index (EI) is used. This article presents an investigation into the Energy Index’s effectiveness to detect early-stage defect initiation and deterioration, and compares it with the common r.m.s. index, Kurtosis, and the Kolmogorov-Smirnov statistical test. It is concluded that EI is a more effective technique for monitoring defect initiation and development than other statistical parameters.Keywords: acoustic emission, signal processing, kurtosis, Kolmogorov-Smirnov test
Procedia PDF Downloads 36610285 Teaching–Learning-Based Optimization: An Efficient Method for Chinese as a Second Language
Authors: Qi Wang
Abstract:
In the classroom, teachers have been trained to complete the target task within the limited lecture time, meanwhile learners need to receive a lot of new knowledge, however, most of the time the learners come without the proper pre-class preparation to efficiently take in the contents taught in class. Under this circumstance, teachers do have no time to check whether the learners fully understand the content or not, how the learners communicate in the different contexts, until teachers see the results when the learners are tested. In the past decade, the teaching of Chinese has taken a trend. Teaching focuses less on the use of proper grammatical terms/punctuation and is now placing a heavier focus on the materials from real life contexts. As a result, it has become a greater challenge to teachers, as this requires teachers to fully understand/prepare what they teach and explain the content with simple and understandable words to learners. On the other hand, the same challenge also applies to the learners, who come from different countries. As they have to use what they learnt, based on their personal understanding of the material to effectively communicate with others in the classroom, even in the contexts of a day to day communication. To reach this win-win stage, Feynman’s Technique plays a very important role. This practical report presents you how the Feynman’s Technique is applied into Chinese courses, both writing & oral, to motivate the learners to practice more on writing, reading and speaking in the past few years. Part 1, analysis of different teaching styles and different types of learners, to find the most efficient way to both teachers and learners. Part 2, based on the theory of Feynman’s Technique, how to let learners build the knowledge from knowing the name of something to knowing something, via different designed target tasks. Part 3. The outcomes show that Feynman’s Technique is the interaction of learning style and teaching style, the double-edged sword of Teaching & Learning Chinese as a Second Language.Keywords: Chinese, Feynman’s technique, learners, teachers
Procedia PDF Downloads 15410284 Surface Activation of Carbon Nanotubes Generating a Chemical Interaction in Epoxy Nanocomposite
Authors: Mohamed Eldessouki, Ebraheem Shady, Yasser Gowayed
Abstract:
Carbon nanotubes (CNTs) are known for having high elastic properties with high surface area that promote them as good candidates for reinforcing polymeric matrices. In composite materials, CNTs lack chemical bonding with the surrounding matrix which decreases the possibility of better stress transfer between the components. In this work, a chemical treatment for activating the surface of the multi-wall carbon nanotubes (MWCNT) was applied and the effect of this functionalization on the elastic properties of the epoxy nanocomposites was studied. Functional amino-groups were added to the surface of the CNTs and it was evaluated to be about 34% of the total weight of the CNTs. Elastic modulus was found to increase by about 40% of the neat epoxy resin at CNTs’ weight fraction of 0.5%. The elastic modulus was found to decrease after reaching a certain concentration of CNTs which was found to be 1% wt. The scanning electron microscopic pictures showed the effect of the CNTs on the crack propagation through the sample by forming stress concentrated spots at the nanocomposite samples.Keywords: carbon nanotubes functionalization, crack propagation, elastic modulus, epoxy nanocomposites
Procedia PDF Downloads 40510283 Polymorphic Positions, Haplotypes, and Mutations Detected In The Mitochonderial DNA Coding Region By Sanger Sequence Technique
Authors: Imad H. Hameed, Mohammad A. Jebor, Ammera J. Omer
Abstract:
The aim of this research is to study the mitochonderial coding region by using the Sanger sequencing technique and establish the degree of variation characteristic of a fragment. FTA® Technology (FTA™ paper DNA extraction) utilized to extract DNA. Portion of coding region encompassing positions 11719 –12384 amplified in accordance with the Anderson reference sequence. PCR products purified by EZ-10 spin column then sequenced and Detected by using the ABI 3730xL DNA Analyzer. Five new polymorphic positions 11741, 11756, 11878, 11887 and 12133 are described may be suitable sources for identification purpose in future. The calculated value D= 0.95 and RMP=0.048 of the genetic diversity should be understood as high in the context of coding function of the analysed DNA fragment. The relatively high gene diversity and a relatively low random match probability were observed in Iraq population. The obtained data can be used to identify the variable nucleotide positions characterized by frequent occurrence which is most promising for various identifications.Keywords: coding region, Iraq, mitochondrial DNA, polymorphic positions, sanger technique
Procedia PDF Downloads 43710282 Sensitizing Bamboo Fabric with Antimicrobial Turmeric Dye
Authors: Varinder Kaur, Amanjit Kaur, Simran Kaur, Samriti Vaid
Abstract:
Coating of fabrics with anti-microbial dyes is an adaptable technique of protection from various diseases. Natural dyes, which are known to possess antibacterial properties, can be used for antibacterial finishing of fibers like cotton, wool, bamboo and so many. Dyeing of fabrics with natural dyes normally requires the use of mordants so that dyes can stay on the fabric as well as into interstices of the fabric during multiple washings. In this study, the mordants used are alum and chitosan for ensuring a reasonable color fastness to light and washing. Chitosan is a natural polysaccharide having significant biological and chemical properties such as biodegradability, biocompatibility, bioactivity, microbial activity and polycationicity. The metal ion of alum mordant can act as electron acceptor for electron donor to form coordination bond with the dye molecule, making them insoluble in water. The dyeing of bamboo fabric using a natural dye extracted from turmeric has been studied using conventional dyeing method. Natural dye was extracted using water as solvent by Soxhlet extraction method. The extracted color was characterized by spectroscopic studies like UV/visible and further tested for antimicrobial activity. The effect of mordants on the dyeing outcome in terms of colour depth as well as fastness properties of the dyeing was investigated. It has been found that employing the conventional dyeing technique at 100 oC, the mordanted samples were deeper in depth than their unmordanted counterparts. The results of fastness properties of the dyed fabrics were fair to good. Turmeric extract was found to enhance microbial resistance of bamboo as well as was itself as a good cause of coloration. These textiles dyed with the turmeric as natural dye can be very useful in developing clothing for infants, elderly and infirm people to protect them against common infections. The outcome of this study will provide a new feature to the interface of dyeing and pharmaceutical industry.Keywords: antimicrobial activity, bamboo fabric, natural dye, turmeric
Procedia PDF Downloads 16910281 A Unique Exact Approach to Handle a Time-Delayed State-Space System: The Extraction of Juice Process
Authors: Mohamed T. Faheem Saidahmed, Ahmed M. Attiya Ibrahim, Basma GH. Elkilany
Abstract:
This paper discusses the application of Time Delay Control (TDC) compensation technique in the juice extraction process in a sugar mill. The objective is to improve the control performance of the process and increase extraction efficiency. The paper presents the mathematical model of the juice extraction process and the design of the TDC compensation controller. Simulation results show that the TDC compensation technique can effectively suppress the time delay effect in the process and improve control performance. The extraction efficiency is also significantly increased with the application of the TDC compensation technique. The proposed approach provides a practical solution for improving the juice extraction process in sugar mills using MATLAB Processes.Keywords: time delay control (TDC), exact and unique state space model, delay compensation, Smith predictor.
Procedia PDF Downloads 9210280 The Effect of Soil Contamination on Chemical Composition and Quality of Aronia (Aronia melanocarpa) Fruits
Authors: Violina R. Angelova, Sava G. Tabakov, Aleksander B. Peltekov, Krasimir I. Ivanov
Abstract:
A field study was conducted to evaluate the chemical composition and quality of the Aronia fruits, as well as the possibilities of Aronia cultivation on soils contaminated with heavy metals. The experiment was performed on an agricultural field contaminated by the Non-Ferrous-Metal Works (NFMW) near Plovdiv, Bulgaria. The study included four varieties of Aronia; Aron variety, Hugin variety, Viking variety and Nero variety. The Aronia was cultivated according to the conventional technology on areas at a different distance from the source of pollution NFMW- Plovdiv (1 km, 3.5 km, and 15 km). The concentrations of macroelements, microelements, and heavy metals in Aronia fruits were determined. The dry matter content, ash, sugars, proteins, and fats were also determined. Aronia is a crop that is tolerant to heavy metals and can successfully be grown on soils contaminated with heavy metals. The increased content of heavy metals in the soil leads to less absorption of the nutrients (Ca, Mg and P) in the fruit of the Aronia. Soil pollution with heavy metals does not affect the quality of the Aronia fruit varieties.Keywords: aronia, chemical composition, fruits, quality
Procedia PDF Downloads 20410279 Soot Formation in the Field of Combustion
Authors: Nacira Mecheri, N. Boussid
Abstract:
A new chemical mechanism designed to study the process of forming the first aromatic ring (benzene) and polycyclic aromatic hydrocarbons (PAH) from a flame of acetylene (C2H2) has been developed. The mechanism developed, contains 50 chemical species involved in 268 reversible elementary reactions. The comparison between the results from modelling and experimental measurements allowed us to test the validity of the postulated mechanism in specific experimental conditions. Kinetic analysis of the flame by calculating the maximum rates for each elementary reaction, allowed us to identify key reactions pathways of consumption and formation of main precursors of soot.Keywords: benzene, PAH, acetylene, modeling, flame, soot
Procedia PDF Downloads 33510278 The Preparation of High Surface Area Ni/MgAl2O4 Catalysts for Syngas Methanation
Authors: Jingyu Zhou, Hongfang Ma, Haitao Zhang, Weiyong Ying
Abstract:
High surface area MgAl2O4 supported Nickel catalysts with PVA loadings varying from 0% to 15% were prepared by precipitation and impregnation method. The catalysts were characterized by low temperature N2 adsorption/desorption, X-ray diffraction and H2 temperature programmed reduction. Compared with Ni/γ-Al2O3 catalyst, Ni/MgAl2O4 catalysts exhibited higher activity and selectivity in high temperature. Among the catalysts, Ni/MgAl2O4-5P with 5 wt% PVA showed the best performance, and achieved 95% CO conversion and 96% CH4 selectivity at 600°C, 2.0 MPa, and a WHSV of 12,000 mL·g⁻¹.h⁻¹. It also maintained good stability in 50h life test.Keywords: methanation, MgAl2O4 support, PVA, high surface area
Procedia PDF Downloads 33510277 Production and Valorization of Nano Lignins by Organosolv and Steam Explosion
Authors: V. Girard, I. Ziegler-Devin, H. Chapuis, N. Canilho, L. Marchal-Heussler, N. Brosse
Abstract:
Lignocellulosic biomass is made up of the three polymeric fractions that are cellulose, hemicellulose, and lignin, which are highly entangled. In this project, we are particularly interested in the under-valued lignin polymer, which is mainly used for thermal valorization. Lignin from Macro to Nanosize (LIMINA) project will first focus on the extraction of macro lignin from forestry waste (hardwood and softwood) by the mean of eco-friendly processes (organosolv and steam explosion) and then the valorization of nano lignins produced by using anti-solvent precipitation (UV-blocker, cosmetic, food products).Keywords: nanolignin, nanoparticles, organosolv, steam explosion
Procedia PDF Downloads 13010276 Wastewater Treatment by Modified Bentonite
Authors: Mecabih Zohra
Abstract:
Water is such an important element of many manufacturing processes which that use a big amount of chemical substances, It is likely to cause it contamination of water returning to rivers by industrial discharged. These contaminants can be a high in suspended solid and chemical oxygen demand. In this study, urban wastewater of sidi bel abbes city (Algeria) was treated by adsorption using modified bentonite from Magnia (Algeria) by conducting batch experiments to investigate its equilibrium characteristics and kinetics. Purified bentonite is characterized by; CEC, XRF, BET, FITR, XRD, SEM and 27Al spectroscopy. The results showed the removal of suspended solids exceeds 98.47% and COD up to 99.52%, and regarding of sorption efficiencies (qm), the maximum COD sorption efficiencies (qm) calculated using the Langmuir model is 156.23, 64.47 and 17.19 mg/g respectively, for a pH range of 4 to 9.Keywords: adsorption, bentonite, COD, wastewater
Procedia PDF Downloads 8510275 Wastewater Treatment by Modified Bentonite
Authors: Mecabih Zohra
Abstract:
Water is such an important element of many manufacturing processes which that use a big amount of chemical substances, It is likely to cause it contamination of water returning to rivers by industrial discharged. These contaminants can be a high in suspended solid and chemical oxygen demand. In this study, urban wastewater of sidi bel abbes city (Algeria) was treated by adsorption using modified bentonite from Magnia (Algeria) by conducting batch experiments to investigate its equilibrium characteristics and kinetics. Purified bentonite is characterized by; CEC, XRF, BET, FITR, XRD, SEM and 27Al spectroscopy. The results showed the removal of suspended solids exceeds 98.47% and COD up to 99.52%, and regarding of sorption efficiencies (qm), the maximum COD sorption efficiencies (qm) calculated using the Langmuir model is 156.23, 64.47 and 17.19 mg/g respectively, for a pH range of 4 to 9.Keywords: adsorption, bentonite, COD, wastewater
Procedia PDF Downloads 8310274 Early Melt Season Variability of Fast Ice Degradation Due to Small Arctic Riverine Heat Fluxes
Authors: Grace E. Santella, Shawn G. Gallaher, Joseph P. Smith
Abstract:
In order to determine the importance of small-system riverine heat flux on regional landfast sea ice breakup, our study explores the annual spring freshet of the Sagavanirktok River from 2014-2019. Seasonal heat cycling ultimately serves as the driving mechanism behind the freshet; however, as an emerging area of study, the extent to which inland thermodynamics influence coastal tundra geomorphology and connected landfast sea ice has not been extensively investigated in relation to small-scale Arctic river systems. The Sagavanirktok River is a small-to-midsized river system that flows south-to-north on the Alaskan North Slope from the Brooks mountain range to the Beaufort Sea at Prudhoe Bay. Seasonal warming in the spring rapidly melts snow and ice in a northwards progression from the Brooks Range and transitional tundra highlands towards the coast and when coupled with seasonal precipitation, results in a pulsed freshet that propagates through the Sagavanirktok River. The concentrated presence of newly exposed vegetation in the transitional tundra region due to spring melting results in higher absorption of solar radiation due to a lower albedo relative to snow-covered tundra and/or landfast sea ice. This results in spring flood runoff that advances over impermeable early-season permafrost soils with elevated temperatures relative to landfast sea ice and sub-ice flow. We examine the extent to which interannual temporal variability influences the onset and magnitude of river discharge by analyzing field measurements from the United States Geological Survey (USGS) river and meteorological observation sites. Rapid influx of heat to the Arctic Ocean via riverine systems results in a noticeable decay of landfast sea ice independent of ice breakup seaward of the shear zone. Utilizing MODIS imagery from NASA’s Terra satellite, interannual variability of river discharge is visualized, allowing for optical validation that the discharge flow is interacting with landfast sea ice. Thermal erosion experienced by sediment fast ice at the arrival of warm overflow preconditions the ice regime for rapid thawing. We investigate the extent to which interannual heat flux from the Sagavanirktok River’s freshet significantly influences the onset of local landfast sea ice breakup. The early-season warming of atmospheric temperatures is evidenced by the presence of storms which introduce liquid, rather than frozen, precipitation into the system. The resultant decreased albedo of the transitional tundra supports the positive relationship between early-season precipitation events, inland thermodynamic cycling, and degradation of landfast sea ice. Early removal of landfast sea ice increases coastal erosion in these regions and has implications for coastline geomorphology which stress industrial, ecological, and humanitarian infrastructure.Keywords: Albedo, freshet, landfast sea ice, riverine heat flux, seasonal heat cycling
Procedia PDF Downloads 129