Search results for: charge separation
1611 The Trauma Suffered by Left behind Children and Its Impact on Their Emotional Development: A Pilot Study with Brazilian Immigrants in the United States
Authors: Liliane Clark
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Immigrating to a different country may imply having to handle many difficult exertions. There is a particular issue that has to be endured by some immigrants: the children they had to leave behind. It is a phenomenon that occurs with certain frequency. Surprisingly, despite the fact that immigration in the United States is such a large proceeding, there is not much research about the topic in America exploring the trauma of the abandonment caused by this separation and its consequences on the mental health of those children. The term “left behind children” is usually applied to children who were left behind by their parents in their original nation under the care of a noteworthy relative, frequently the grandparents, when they moved to another country. This preliminary research, which is a partial study projected for a doctoral thesis, investigated whether the trauma of abandonment experienced by ten left behind children had affected their emotional development. The Strengths and Difficulties Questionnaire (SDQ) and a brief interview were utilized to assess the information. The SDQ explored scales such as emotional symptoms, conduct problems, hyperactivity, peer problems and prosocial behavior. In this pilot study, the results indicated that all these issues had some sort of significant correlation between them. During the interviews, the participants or their parents identified a range of symptoms: anxiety disorder, eating disorders, panic attacks, psychotic-like experiences, drug use and depression. Hence, it seems that there is a connection between the trauma of abandonment suffered due to the separation and the children’s consequent symptomatic behavior. Further studies are indeed necessary to validate the initial results of this investigation.Keywords: abandonment, parent migration, psychological problems, trauma
Procedia PDF Downloads 1871610 Removal of Lead Ions from Aqueous Medium Using Devised Column Filters Packed with Chitosan from Trash Crab Shells: A Characterization Study
Authors: Charles Klein O. Gorit, Mark Tristan J. Quimque Jr., M. Cecilia V. Almeda, Concepcion M. Salvana
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Chitosan is a promising biopolymer commonly found in crustacean shells that has plausible effects in water purification and wastewater treatment. It is a primary derivative of chitin and considered second of the most abundant biopolymer prior to cellulose. Morphological analysis had been done using Scanning Electron Microscopy with Energy Dispersive Microscopy (SEM/EDS), and due to its porous nature, it showcases a certain degree of porosity, hence, larger adsorption site of heavy metal. The Energy Dispersive Spectroscopy of the chitosan and ‘lead-bound’ chitosan, shows a relative increase of percent abundance of lead cation from 1.44% to 2.08% hence, adsorption occurs. Chitosan, as a nitrogenous polysaccharide, subjected to Fourier transform infrared spectroscopy (FTIR) analysis shows amide bands ranging from 1635.36 cm⁻¹ for amide 1 band and 1558.40 cm-1 for amide 2 band with NH stretching. For ‘lead-bound’ chitosan, the FT-IR analysis shows a change in peaks upon adsorption of Pb(II) cation. The spectrum shows broadening of OH and NH stretching band. Such observation can be attributed to the probability that the attachment of Pb(II) ions is in these functional groups. A column filter was devised with lead-bound chitosan to determine the zero point charge (pHzpc) of the biopolymer. The results show that at pH 8.34, below than the zpc level of literatures cited for lead which ranges from pH 4 to 7, favors the adsorption site of chitosan and its capability to adsorb traces amount of aqueous lead.Keywords: chitosan, biopolymer, FT-IR, SEM, zero-point charge, heavy metal, lead ions
Procedia PDF Downloads 1511609 Optimization of Multistage Extractor for the Butanol Separation from Aqueous Solution Using Ionic Liquids
Authors: Dharamashi Rabari, Anand Patel
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n-Butanol can be regarded as a potential biofuel. Being resistive to corrosion and having high calorific value, butanol is a very attractive energy source as opposed to ethanol. By fermentation process called ABE (acetone, butanol, ethanol), bio-butanol can be produced. ABE carried out mostly by bacteria Clostridium acetobutylicum. The major drawback of the process is the butanol concentration higher than 10 g/L, delays the growth of microbes resulting in a low yield. It indicates the simultaneous separation of butanol from the fermentation broth. Two hydrophobic Ionic Liquids (ILs) 1-butyl-1-methylpiperidinium bis (trifluoromethylsulfonyl)imide [bmPIP][Tf₂N] and 1-hexyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide [hmim][Tf₂N] were chosen. The binary interaction parameters for both ternary systems i.e. [bmPIP][Tf₂N] + water + n-butanol and [hmim][Tf₂N] + water +n-butanol were taken from the literature that was generated by NRTL model. Particle swarm optimization (PSO) with the isothermal sum rate (ISR) method was used to optimize the cost of liquid-liquid extractor. For [hmim][Tf₂N] + water +n-butanol system, PSO shows 84% success rate with the number of stages equal to eight and solvent flow rate equal to 461 kmol/hr. The number of stages was three with 269.95 kmol/hr solvent flow rate for [bmPIP][Tf₂N] + water + n-butanol system. Moreover, both ILs were very efficient as the loss of ILs in raffinate phase was negligible.Keywords: particle swarm optimization, isothermal sum rate method, success rate, extraction
Procedia PDF Downloads 1221608 The Effects of Myelin Basic Protein Charge Isomers on the Methyl Cycle Metabolites in Glial Cells
Authors: Elene Zhuravliova, Tamar Barbakadze, Irina Kalandadze, Elnari Zaalishvili, Lali Shanshiashvili, David Mikeladze
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Background: Multiple sclerosis (MS) is an inflammatory, neurodegenerative disease, which is accompanied by demyelination and autoimmune response to myelin proteins. Among post-translational modifications, which mediate the modulation of inflammatory pathways during MS, methylation is the main one. The methylation of DNA, also amino acids lysine and arginine, occurs in the cell. It was found that decreased trans-methylation is associated with neuroinflammatory diseases. Therefore, abnormal regulation of the methyl cycle could induce demyelination through the action on PAD (peptidyl-arginine-deiminase) gene promoter. PAD takes part in protein citrullination and targets myelin basic protein (MBP), which is affected during demyelination. To determine whether MBP charge isomers are changing the methyl cycle, we have estimated the concentrations of methyl cycle metabolites in MBP-activated primary astrocytes and oligodendrocytes. For this purpose, the action of the citrullinated MBP- C8 and the most cationic MBP-C1 isomers on the primary cells were investigated. Methods: Primary oligodendrocyte and astrocyte cell cultures were prepared from whole brains of 2-day-old Wistar rats. The methyl cycle metabolites, including homocysteine, S-adenosylmethionine (SAM), and S-adenosylhomocysteine (SAH), were estimated by HPLC analysis using fluorescence detection and prior derivatization. Results: We found that the action of MBP-C8 and MBP-C1 induces a decrease in the concentration of both methyl cycle metabolites, S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH), in astrocytes compared to the control cells. As for oligodendrocytes, the concentration of SAM was increased by the addition of MBP-C1, while MBP-C8 has no significant effect. As for SAH, its concentration was increased compared to the control cells by the action of both MBP-C1 and MBP-C8. A significant increase in homocysteine concentration was observed by the action of the MBP-C8 isomer in both oligodendrocytes and astrocytes. Conclusion: These data suggest that MBP charge isomers change the concentration of methyl cycle metabolites. MBP-C8 citrullinated isomer causes elevation of homocysteine in astrocytes and oligodendrocytes, which may be the reason for decreased astrocyte proliferation and increased oligodendrocyte cell death which takes place in neurodegenerative processes. Elevated homocysteine levels and subsequent abnormal regulation of methyl cycles in oligodendrocytes possibly change the methylation of DNA that activates PAD gene promoter and induces the synthesis of PAD, which in turn provokes the process of citrullination, which is the accompanying process of demyelination. Acknowledgment: This research was supported by the SRNSF Georgia RF17_534 grant.Keywords: myelin basic protein, astrocytes, methyl cycle metabolites, homocysteine, oligodendrocytes
Procedia PDF Downloads 1561607 The Scanning Vibrating Electrode Technique (SVET) as a Tool for Optimising a Printed Ni(OH)2 Electrode under Charge Conditions
Authors: C. F. Glover, J. Marinaccio, A. Barnes, I. Mabbett, G. Williams
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The aim of the current study is to optimise formulations, in terms of charging efficiency, of a printed Ni(OH)2 precursor coating of a battery anode. Through the assessment of the current densities during charging, the efficiency of a range of formulations are compared. The Scanning vibrating electrode technique (SVET) is used extensively in the field of corrosion to measure area-averaged current densities of freely-corroding metal surfaces when fully immersed in electrolyte. Here, a Ni(OH)2 electrode is immersed in potassium hydroxide (30% w/v solution) electrolyte and charged using a range of applied currents. Samples are prepared whereby multiple coatings are applied to one substrate, separated by a non-conducting barrier, and charged using a constant current. With a known applied external current, electrode efficiencies can be calculated based on the current density outputs measured using SVET. When fully charged, a green Ni(OH)2 is oxidised to a black NiOOH surface. Distinct regions displaying high current density, and hence a faster oxidising reaction rate, are located using the SVET. This is confirmed by a darkening of the region upon transition to NiOOH. SVET is a highly effective tool for assessing homogeneity of electrodes during charge/discharge. This could prove particularly useful for electrodes where there are no visible surface appearance changes. Furthermore, a scanning Kelvin probe technique, traditionally used to assess underfilm delamination of organic coatings for the protection of metallic surfaces, is employed to study the change in phase of oxides, pre and post charging.Keywords: battery, electrode, nickel hydroxide, SVET, printed
Procedia PDF Downloads 2361606 Estimation of Energy Efficiency of Blue Hydrogen Production Onboard of Ships
Authors: Li Chin Law, Epaminondas Mastorakos, Mohd Roslee Othman, Antonis Trakakis
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The paper introduces an alternative concept of carbon capture for shipping by using pre-combustion carbon capture technology (Pre-CCS), which was proven to be less energy intensive than post-combustion carbon capture from the engine exhaust. Energy assessment on amine-based post-combustion CCS on LNG-fuelled ships showed that the energy efficiency of CCS ships reduced from 48% to 36.6%. Then, an energy assessment was carried out to compare the power and heat requirements of the most used hydrogen production methods and carbon capture technologies. Steam methane reformer (SMR) was found to be 20% more energy efficient and achieved a higher methane conversion than auto thermal reaction and methane decomposition. Next, pressure swing adsorber (PSA) has shown a lower energy requirement than membrane separation, cryogenic separation, and amine absorption in pre-combustion carbon capture. Hence, an integrated system combining SMR and PSA (SMR-PSA) with waste heat integration (WHR) was proposed. This optimized SMR-based integrated system has achieved 65% of CO₂ reduction with less than 7-percentage point of energy penalty (41.7% of energy efficiency). Further integration of post-combustion CCS with the SMR-PSA integrated system improved carbon capture rate to 86.3% with 9-percentage points of energy penalty (39% energy efficiency). The proposed system was shown to be able to meet the carbon reduction targets set by International Maritime Organization (IMO) with certain energy penalties.Keywords: shipping, decarbonisation, alternative fuels, low carbon, hydrogen, carbon capture
Procedia PDF Downloads 781605 Analysis of Lift Force in Hydrodynamic Transport of a Finite Sized Particle in Inertial Microfluidics with a Rectangular Microchannel
Authors: Xinghui Wu, Chun Yang
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Inertial microfluidics is a competitive fluidic method with applications in separation of particles, cells and bacteria. In contrast to traditional microfluidic devices with low Reynolds number, inertial microfluidics works in the intermediate Re number range which brings about several intriguing inertial effects on particle separation/focusing to meet the throughput requirement in the real-world. Geometric modifications to make channels become irregular shapes can leverage fluid inertia to create complex secondary flow for adjusting the particle equilibrium positions and thus enhance the separation resolution and throughput. Although inertial microfluidics has been extensively studied by experiments, our current understanding of its mechanisms is poor, making it extremely difficult to build rational-design guidelines for the particle focusing locations, especially for irregularly shaped microfluidic channels. Inertial particle microfluidics in irregularly shaped channels were investigated in our group. There are several fundamental issues that require us to address. One of them is about the balance between the inertial lift forces and the secondary drag forces. Also, it is critical to quantitatively describe the dependence of the life forces on particle-particle interactions in irregularly shaped channels, such as a rectangular one. To provide physical insights into the inertial microfluidics in channels of irregular shapes, in this work the immersed boundary-lattice Boltzmann method (IB-LBM) was introduced and validated to explore the transport characteristics and the underlying mechanisms of an inertial focusing single particle in a rectangular microchannel. The transport dynamics of a finitesized particle were investigated over wide ranges of Reynolds number (20 < Re < 500) and particle size. The results show that the inner equilibrium positions are more difficult to occur in the rectangular channel, which can be explained by the secondary flow caused by the presence of a finite-sized particle. Furthermore, force decoupling analysis was utilized to study the effect of each type of lift force on the inertia migration, and a theoretical model for the lateral lift force of a finite-sized particle in the rectangular channel was established. Such theoretical model can be used to provide theoretical guidance for the design and operation of inertial microfluidics.Keywords: inertial microfluidics, particle focuse, life force, IB-LBM
Procedia PDF Downloads 711604 Electrocatalytic Properties of Ru-Pd Bimetal Quantum Dots/TiO₂ Nanotube Arrays Electrodes Composites with Double Schottky Junctions
Authors: Shiying Fan, Xinyong Li
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The development of highly efficient multifunctional catalytic materials towards HER, ORR and Photo-fuel cell applications in terms of combined electrochemical and photo-electrochemical principles have currently confronted with dire challenges. In this study, novel palladium (Pd) and ruthenium (Ru) Bimetal Quantum Dots (BQDs) co-anchored on Titania nanotube (NTs) arrays electrodes have been successfully constructed by facial two-step electrochemical strategy. Double Schottky junctions with superior performance in electrocatalytic (EC) hydrogen generations and solar fuel cell energy conversions (PE) have been found. Various physicochemical techniques including UV-vis spectroscopy, TEM/EDX/HRTEM, SPV/TRV and electro-chemical strategy including EIS, C-V, I-V, and I-T, etc. were chronically utilized to systematically characterize the crystal-, electronic and micro-interfacial structures of the composites with double Schottky junction, respectively. The characterizations have implied that the marvelous enhancement of separation efficiency of electron-hole pairs generations is mainly caused by the Schottky-barriers within the nanocomposites, which would greatly facilitate the interfacial charge transfer for H₂ generations and solar fuel cell energy conversions. Moreover, the DFT calculations clearly indicated that the oriented growth of Ru and Pd bimetal atoms at the anatase (101) surface is mainly driven by the interaction between Ru/Pd and surface atoms, and the most active site for bimetal Ru and Pd adatoms on the perfect TiO₂ (101) surface is the 2cO-6cTi-3cO bridge sites and the 2cO-bridge sites with the highest adsorption energy of 9.17 eV. Furthermore, the electronic calculations show that in the nanocomposites, the number of impurity (i.e., co-anchored Ru-Pd BQDs) energy levels near Fermi surface increased and some were overlapped with original energy level, promoting electron energy transition and reduces the band gap. Therefore, this work shall provide a deeper insight for the molecular design of Bimetal Quantum Dots (BQDs) assembled onto Tatiana NTs composites with superior performance for electrocatalytic hydrogen productions and solar fuel cell energy conversions (PE) simultaneously.Keywords: eletrocatalytic, Ru-Pd bimetallic quantum dots, titania nanotube arrays, double Schottky junctions, hydrogen production
Procedia PDF Downloads 1431603 Synthesis of Visible-Light-Driven Magnetically Recoverable N-TiO2@SiO2@Fe3O4 Nanophotocatalyst for Enhanced Degradation of Ibuprofen
Authors: Ashutosh Kumar, Irene M. C. Lo
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Ever since the discovery of TiO2 for decomposition of cyanide in water, it has been investigated extensively for the photocatalytic degradation of environmental pollutants, and became the most practical and prevalent photocatalyst. The superiority of TiO2 is due to its chemical and biological inertness, nontoxicity, strong oxidizing power and cost-effectiveness. However, during degradation of pollutants in wastewater, it suffers from problems, such as (a) separation after use, and (b) its poor photocatalytic performance under visible light irradiation (~45% of the solar spectrum). In order to bridge the research gaps, N-TiO2@SiO2@Fe3O4 nanophotocatalysts of average size 19 nm and effective surface area 47 m2 gm-1 were synthesized using sol-gel method. The characterization was performed using BET, TEM-EDX, VSM and XRD. The performance was improved by considering different factors involved during the synthesis, such as calcination temperature, amount of Fe3O4 nanoparticles used and amount of urea used for N-doping. The final nanophotocatalyst was calcined at 500 °C which was able to degrade 94% of the ibuprofen within 5 h of irradiation time. Under the influence of ~200 mT electromagnetic field, 95% nanophotocatalysts separation efficiency was achieved within 20-25 min. Moreover, the effect of different visible light source of similar irradiance, such as compact fluorescent lamp (CFL) and light emitting diode (LED), is also investigated in this research. The performance of nanophotocatalysts was found to be comparatively higher under ~310 µW cm-2 irradiance with peak emissive wavelengths of 543 nm emitted by CFL. Therefore, a promising visible-light-driven magnetically separable TiO2-based nanophotocatalysts was synthesized for the efficient degradation of ibuprofen.Keywords: ibuprofen, magnetic N-TiO2, photocatalysis, visible light sources
Procedia PDF Downloads 2481602 Ionic Liquids as Substrates for Metal-Organic Framework Synthesis
Authors: Julian Mehler, Marcus Fischer, Martin Hartmann, Peter S. Schulz
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During the last two decades, the synthesis of metal-organic frameworks (MOFs) has gained ever increasing attention. Based on their pore size and shape as well as host-guest interactions, they are of interest for numerous fields related to porous materials, like catalysis and gas separation. Usually, MOF-synthesis takes place in an organic solvent between room temperature and approximately 220 °C, with mixtures of polyfunctional organic linker molecules and metal precursors as substrates. Reaction temperatures above the boiling point of the solvent, i.e. solvothermal reactions, are run in autoclaves or sealed glass vessels under autogenous pressures. A relatively new approach for the synthesis of MOFs is the so-called ionothermal synthesis route. It applies an ionic liquid as a solvent, which can serve as a structure-directing template and/or a charge-compensating agent in the final coordination polymer structure. Furthermore, this method often allows for less harsh reaction conditions than the solvothermal route. Here a variation of the ionothermal approach is reported, where the ionic liquid also serves as an organic linker source. By using 1-ethyl-3-methylimidazolium terephthalates ([EMIM][Hbdc] and [EMIM]₂[bdc]), the one-step synthesis of MIL-53(Al)/Boehemite composites with interesting features is possible. The resulting material is already formed at moderate temperatures (90-130 °C) and is stabilized in the usually unfavored ht-phase. Additionally, in contrast to already published procedures for MIL-53(Al) synthesis, no further activation at high temperatures is mandatory. A full characterization of this novel composite material is provided, including XRD, SS-NMR, El-Al., SEM as well as sorption measurements and its interesting features are compared to MIL-53(Al) samples produced by the classical solvothermal route. Furthermore, the syntheses of the applied ionic liquids and salts is discussed. The influence of the degree of ionicity of the linker source [EMIM]x[H(2-x)bdc] on the crystal structure and the achievable synthesis temperature are investigated and give insight into the role of the IL during synthesis. Aside from the synthesis of MIL-53 from EMIM terephthalates, the use of the phosphonium cation in this approach is discussed as well. Additionally, the employment of ILs in the preparation of other MOFs is presented briefly. This includes the ZIF-4 framework from the respective imidazolate ILs and chiral camphorate based frameworks from their imidazolium precursors.Keywords: ionic liquids, ionothermal synthesis, material synthesis, MIL-53, MOFs
Procedia PDF Downloads 2081601 Kinetic and Removable of Amoxicillin Using Aliquat336 as a Carrier via a HFSLM
Authors: Teerapon Pirom, Ura Pancharoen
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Amoxicillin is an antibiotic which is widely used to treat various infections in both human beings and animals. However, when amoxicillin is released into the environment, it is a major problem. Amoxicillin causes bacterial resistance to these drugs and failure of treatment with antibiotics. Liquid membrane is of great interest as a promising method for the separation and recovery of the target ions from aqueous solutions due to the use of carriers for the transport mechanism, resulting in highly selectivity and rapid transportation of the desired metal ions. The simultaneous processes of extraction and stripping in a single unit operation of liquid membrane system are very interesting. Therefore, it is practical to apply liquid membrane, particularly the HFSLM for industrial applications as HFSLM is proved to be a separation process with lower capital and operating costs, low energy and extractant with long life time, high selectivity and high fluxes compared with solid membranes. It is a simple design amenable to scaling up for industrial applications. The extraction and recovery for (Amoxicillin) through the hollow fiber supported liquid membrane (HFSLM) using aliquat336 as a carrier were explored with the experimental data. The important variables affecting on transport of amoxicillin viz. extractant concentration and operating time were investigated. The highest AMOX- extraction percentages of 85.35 and Amoxicillin stripping of 80.04 were achieved with the best condition at 6 mmol/L [aliquat336] and operating time 100 min. The extraction reaction order (n) and the extraction reaction rate constant (kf) were found to be 1.00 and 0.0344 min-1, respectively.Keywords: aliquat336, amoxicillin, HFSLM, kinetic
Procedia PDF Downloads 2751600 A Cohesive Zone Model with Parameters Determined by Uniaxial Stress-Strain Curve
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A key issue of cohesive zone models is how to determine the cohesive zone model parameters based on real material test data. In this paper, uniaxial nominal stress-strain curve (SS curve) is used to determine two key parameters of a cohesive zone model (CZM): The maximum traction and the area under the curve of traction-separation law (TSL). To this end, the true SS curve is obtained based on the nominal SS curve, and the relationship between the nominal SS curve and TSL is derived based on an assumption that the stress for cracking should be the same in both CZM and the real material. In particular, the true SS curve after necking is derived from the nominal SS curve by taking the average of the power law extrapolation and the linear extrapolation, and a damage factor is introduced to offset the true stress reduction caused by the voids generated at the necking zone. The maximum traction of the TSL is equal to the maximum true stress calculated based on the damage factor at the end of hardening. In addition, a simple specimen is modeled by Abaqus/Standard to calculate the critical J-integral, and the fracture energy calculated by the critical J-integral represents the stored strain energy in the necking zone calculated by the true SS curve. Finally, the CZM parameters obtained by the present method are compared to those used in a previous related work for a simulation of the drop-weight tear test.Keywords: dynamic fracture, cohesive zone model, traction-separation law, stress-strain curve, J-integral
Procedia PDF Downloads 4741599 Determination of Cohesive Zone Model’s Parameters Based On the Uniaxial Stress-Strain Curve
Authors: Y. J. Wang, C. Q. Ru
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A key issue of cohesive zone models is how to determine the cohesive zone model (CZM) parameters based on real material test data. In this paper, uniaxial nominal stress-strain curve (SS curve) is used to determine two key parameters of a cohesive zone model: the maximum traction and the area under the curve of traction-separation law (TSL). To this end, the true SS curve is obtained based on the nominal SS curve, and the relationship between the nominal SS curve and TSL is derived based on an assumption that the stress for cracking should be the same in both CZM and the real material. In particular, the true SS curve after necking is derived from the nominal SS curve by taking the average of the power law extrapolation and the linear extrapolation, and a damage factor is introduced to offset the true stress reduction caused by the voids generated at the necking zone. The maximum traction of the TSL is equal to the maximum true stress calculated based on the damage factor at the end of hardening. In addition, a simple specimen is simulated by Abaqus/Standard to calculate the critical J-integral, and the fracture energy calculated by the critical J-integral represents the stored strain energy in the necking zone calculated by the true SS curve. Finally, the CZM parameters obtained by the present method are compared to those used in a previous related work for a simulation of the drop-weight tear test.Keywords: dynamic fracture, cohesive zone model, traction-separation law, stress-strain curve, J-integral
Procedia PDF Downloads 5131598 The Effect of Torsional Angle on Reversible Electron Transfer in Donor: Acceptor Frameworks Using Bis(Imino)Pyridines as Proxy
Authors: Ryan Brisbin, Hassan Harb, Justin Debow, Hrant Hratchian, Ryan Baxter
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Donor-Acceptor (DA) frameworks are crucial parts of any technology requiring charge transport. This type of behavior is ubiquitous across technologies from semi conductors to solar panels. Currently, most DA systems involve metallic components, but progressive research is being pursued to design fully organic DA systems to be used as both organic semi-conductors and light emitting diodes. These systems are currently comprised of conductive polymers and salts. However, little is known about the effect of various physical aspects (size, torsional angle, electron density) have on the act of reversible charge transfer. Herein, the effect of torsional angle on reductive stability in bis(imino)pyridines is analyzed using a combination of single crystal analysis and electro-chemical peak current ratios from cyclic voltammetry. The computed free energies of reduction and electron attachment points were also investigated through density functional theory and natural ionization orbital theory to gain greater understanding of the global effect torsional angles have on electron transfer in bis(imino)pyridines. Findings indicated that torsional angles are a multi-variable parameter affected by both local steric constraints and resonant electronic contributions. Local steric impacted torsional angles demonstrated a negligible effect on electrochemical reversibility, while resonant affected torsional angles were observed to significantly alter the electrochemical reversibility.Keywords: cyclic voltammetry, bis(imino)pyridines, structure-activity relationship, torsional angles
Procedia PDF Downloads 2371597 A Case of Borderline Personality Disorder: An Explanatory Study of Unconscious Conflicts through Dream-Analysis
Authors: Mariam Anwaar, Kiran B. Ahmad
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Borderline Personality Disorder (BPD) is an invasive presence of affect instability, disturbance in self-concept and attachment in relationships. The profound indicator is the dichotomous approach of the world in which the ego categorizes individuals, especially their significant others, into secure or threatful beings, leaving little room for a complex combination of characteristics in one person. This defense mechanism of splitting their world has been described through the explanatory model of unconscious conflict theorized by Sigmund Freud’s Electra Complex in the Phallic Stage. The central role is of the father with whom the daughter experiences penis envy, thus identifying with the mother’s characteristics to receive the father’s attention. However, Margret Mahler, an object relation theorist, elucidates the central role of the mother and that the split occurs during the pre-Electra complex stage. Amid the 14 and 24 months of the infant, it acknowledges the world away from the mother as they have developed milestones such as crawling. In such novelty, the infant crawls away from the mother creating a sense of independence (individuation). On the other hand, being distant causes anxiety, making them return to their original object of security (separation). In BPD, the separation-individuation stage is disrupted, due to contradictory actions of the caregiver, which results in splitting the object into negative and positive aspects, repressing the former and adhering to the latter for survival. Thus, with time, the ego distorts the reality into dichotomous categories, using the splitting defenses, and the mental representation of the self is distorted due to the internalization of the negative objects. The explanatory model was recognized in the case study of Fizza, at 21-year-old Pakistani female, residing in Karachi. Her marital status is single with an occupation being a dental student. Fizza lives in a nuclear family but is surrounded by her extended family as they all are in close vicinity. She came with the complaints of depressive symptoms for two-years along with self-harm due to severe family conflicts. Through the intervention of Dialectical Behavior Therapy (DBT), the self-harming actions were reduced, however, this libidinal energy transformed into claustrophobic symptoms and, along with this, Fizza has always experienced vivid dreams. A retrospective method of Jungian dream-analysis was applied to locate the origins of the splitting in the unconscious. The result was the revelation of a sexual harassment trauma at the age of six-years which was displaced in the form of self-harm. In addition to this, the presence of a conflict at the separation-individuation stage was detected during the dream-analysis, and it was the underlying explanation of the claustrophobic symptoms. This qualitative case study implicates the use of a patient’s subjective experiences, such as dreams, to journey through the spiral of the unconscious in order to not only detect repressed memories but to use them in psychotherapy as a means of healing the patient.Keywords: borderline personality disorder, dream-analysis, Electra complex, separation-individuation, splitting, unconscious
Procedia PDF Downloads 1531596 Electrocatalysts for Lithium-Sulfur Energy Storage Systems
Authors: Mirko Ante, Şeniz Sörgel, Andreas Bund
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Li-S- (Lithium-Sulfur-) battery systems provide very high specific gravimetric energy (2600 Wh/kg) and volumetric energy density (2800Wh/l). Hence, Li-S batteries are one of the key technologies for both the upcoming electromobility and stationary applications. Furthermore, the Li-S battery system is potentially cheap and environmentally benign. However, the technical implementation suffers from cycling stability, low charge and discharge rates and incomplete understanding of the complex polysulfide reaction mechanism. The aim of this work is to develop an effective electrocatalyst for the polysulfide reactions so that the electrode kinetics of the sulfur half-cell will be improved. Accordingly, the overvoltage will be decreased, and the efficiency of the cell will be increased. An enhanced electroactive surface additionally improves the charge and discharge rates. To reach this goal, functionalized electrocatalytic coatings are investigated to accelerate the kinetics of the polysulfide reactions. In order to determine a suitable electrocatalyst, apparent exchange current densities of a variety of materials (Ni, Co, Pt, Cr, Al, Cu, ITO, stainless steel) have been evaluated in a polysulfide containing electrolyte by potentiodynamic measurements and a Butler-Volmer fit including diffusion limitation. The samples have been examined by Scanning Electron Microscopy (SEM) after the potentiodynamic measurements. Up to now, our work shows that cobalt is a promising material with good electrocatalytic properties for the polysulfide reactions and good chemical stability in the system. Furthermore, an electrodeposition from a modified Watt’s nickel electrolyte with a sulfur source seems to provide an autocatalytic effect, but the electrocatalytic behavior decreases after several cycles of the current-potential-curve.Keywords: electrocatalyst, energy storage, lithium sulfur battery, sulfur electrode materials
Procedia PDF Downloads 3681595 Development of Stability Indicating Method and Characterization of Degradation Impurity of Nirmaltrelvir in Its Self-Emulsifying Drug Delivery System
Authors: Ravi Patel, Ravisinh Solanki, Dignesh Khunt
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A stability-indicating reverse phase high performance liquid chromatography (RP-HPLC) method was developed and validated for estimating Nirmatrelvir in its self-emulsifying drug delivery system (SEDDS). The separation of Nirmatrelvir and its degradation products was accomplished by employing an Agilent Zorbax Eclipse plus C18 (250 mm x 4.6 mm, 5 µm) column, through which the mobile phase 5 mM phosphate buffer (pH 4.0) as mobile phase A and Acetonitrile as mobile phase B in a ratio of (40:60 % v/v) was pumped at a flow rate of 1.0 mL/min, through the HPLC system. Chromatographic separation and elution were monitored by a photo-diode array detector at 210 nm. Stress studies have been employed to evaluate this method's ability to indicate stability. Nirmatrelvir was exposed to several stress conditions, such as acid, alkali, oxidative, photolytic, and thermal degradations. Significant degradation was observed during acid and alkali hydrolysis, and the resulting degradation product was successfully separated from the Nirmatrelvir peak, preventing any interference. Furthermore, the primary degradant produced under alkali degradation conditions was identified using UPLC-ESI-TQ-MS/MS. The method was validated in accordance with the International Council on Harmonization (ICH) and found to be selective, precise, accurate, linear, and robust. The apparent permeability of Nirmatrelvir SEDDS was 4.20 ± 0.21×10-6 cm/sec, and the average proportion of free drug recovered was 0.5%. The method developed in this study was feasible and accurate for routine quality control evaluation of Nirmatrelvir SEDDS.Keywords: Nirmatrelvir, SEDDS, degradation study, HPLC, LC-MS/MS
Procedia PDF Downloads 181594 Conditionality in the European Union as a New Instrument to Guarantee the Principle of Separation of Powers
Authors: Ana Neves
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The European Union’s multi-level constitutionalism is grounded in an intricate network of vertical and horizontal legal relationships among different levels and types of public authorities. In a very significant way since the 2008 crisis, evolving institutional arrangements and institutional dynamics in the European Union have been progressively impacting Member States and the terms under which national public authorities are organised, interact and exercise their powers. This impact occurs in both macro and micro dimensions. Several examples are relevant here, such as the involvement of national Parliaments in the activities of the European Union, the enhanced integration of public administrations, the side effects of the Council framework decision on the European Arrest Warrant, the European Union Justice Scoreboard, the protection of whistle-blowers regulation, the enhanced cooperation on the establishment of the European Public Prosecutor’s Office, the regime for the protection of the Union budget and the European Rule of Law Mechanism. A common trend or denominator underlies the deepening of institutional interdependence and the increased interactions between the European Union, Member States, and public authorities at different levels. This seems to be conditionality as a general principle. The European multi-level constitutionalism must be considered in the light of this conditionality principle, which does not “imply a relationship of command and obedience”. Nevertheless, it might be more effective or be a very compelling principle. It is as if the extension of the shared rule is being accompanied by a contrapuntal dialogue. The different public authorities at various levels are being called to rethink and readjust themselves within a broader and more plural framework concerning understanding the limitation of power.Keywords: european union -, multi-level hierarchy, conditionality, separation of powers
Procedia PDF Downloads 1071593 Finite Deformation of a Dielectric Elastomeric Spherical Shell Based on a New Nonlinear Electroelastic Constitutive Theory
Authors: Odunayo Olawuyi Fadodun
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Dielectric elastomers (DEs) are a type of intelligent materials with salient features like electromechanical coupling, lightweight, fast actuation speed, low cost and high energy density that make them good candidates for numerous engineering applications. This paper adopts a new nonlinear electroelastic constitutive theory to examine radial deformation of a pressurized thick-walled spherical shell of soft dielectric material with compliant electrodes on its inner and outer surfaces. A general formular for the internal pressure, which depends on the deformation and a potential difference between boundary electrodes or uniform surface charge distributions, is obtained in terms of special function. To illustrate the effects of an applied electric field on the mechanical behaviour of the shell, three different energy functions with distinct mechanical properties are employed for numerical purposes. The observed behaviour of the shells is preserved in the presence of an applied electric field, and the influence of the field due to a potential difference declines more slowly with the increasing deformation to that produced by a surface charge. Counterpart results are then presented for the thin-walled shell approximation as a limiting case of a thick-walled shell without restriction on the energy density. In the absence of internal pressure, it is obtained that inflation is caused by the application of an electric field. The resulting numerical solutions of the theory presented in this work are in agreement with those predicted by the generally adopted Dorfmann and Ogden model.Keywords: constitutive theory, elastic dielectric, electroelasticity, finite deformation, nonlinear response, spherical shell
Procedia PDF Downloads 931592 Review of Strategies for Hybrid Energy Storage Management System in Electric Vehicle Application
Authors: Kayode A. Olaniyi, Adeola A. Ogunleye, Tola M. Osifeko
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Electric Vehicles (EV) appear to be gaining increasing patronage as a feasible alternative to Internal Combustion Engine Vehicles (ICEVs) for having low emission and high operation efficiency. The EV energy storage systems are required to handle high energy and power density capacity constrained by limited space, operating temperature, weight and cost. The choice of strategies for energy storage evaluation, monitoring and control remains a challenging task. This paper presents review of various energy storage technologies and recent researches in battery evaluation techniques used in EV applications. It also underscores strategies for the hybrid energy storage management and control schemes for the improvement of EV stability and reliability. The study reveals that despite the advances recorded in battery technologies there is still no cell which possess both the optimum power and energy densities among other requirements, for EV application. However combination of two or more energy storages as hybrid and allowing the advantageous attributes from each device to be utilized is a promising solution. The review also reveals that State-of-Charge (SoC) is the most crucial method for battery estimation. The conventional method of SoC measurement is however questioned in the literature and adaptive algorithms that include all model of disturbances are being proposed. The review further suggests that heuristic-based approach is commonly adopted in the development of strategies for hybrid energy storage system management. The alternative approach which is optimization-based is found to be more accurate but is memory and computational intensive and as such not recommended in most real-time applications.Keywords: battery state estimation, hybrid electric vehicle, hybrid energy storage, state of charge, state of health
Procedia PDF Downloads 2421591 Applications of High Intensity Ultrasound to Modify Millet Protein Concentrate Functionality
Authors: B. Nazari, M. A. Mohammadifar, S. Shojaee-Aliabadi, L. Mirmoghtadaie
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Millets as a new source of plant protein were not used in food applications due to its poor functional properties. In this study, the effect of high intensity ultrasound (frequency: 20 kHz, with contentious flow) (US) in 100% amplitude for varying times (5, 12.5, and 20 min) on solubility, emulsifying activity index (EAI), emulsion stability (ES), foaming capacity (FC), and foaming stability (FS) of millet protein concentrate (MPC) were evaluated. In addition, the structural properties of best treatments such as molecular weight and surface charge were compared with the control sample to prove the US effect. The US treatments significantly (P<0.05) increased the solubility of the native MPC (65.8±0.6%) at all sonicated times with the maximum solubility that is recorded at 12.5 min treatment (96.9±0.82 %). The FC of MPC was also significantly affected by the US treatment. Increase in sonicated time up to 12.5 min significantly increased the FC of native MPC (271.03±4.51 ml), but higher increase reduced it significantly. Minimal improvements were observed in the FS of all sonicated MPC compared to the native MPC. Sonicated time for 12.5 min affected the EAI and ES of the native MPC more markedly than 5 and 20 min that may be attributed to higher increase in proteins tendency to adsorption at the oil and water interfaces after the US treatment at this time. SDS-PAGE analysis showed changes in the molecular weight of MPC that attributed to shearing forces created by cavitation phenomenon. Also, this phenomenon caused an increase in the exposure of more amino acids with negative charge in the surface of US treated MPC, that was demonstrated by Zetasizer data. High intensity ultrasound, as a green technology, can significantly increase the functional properties of MPC and can make this usable for food applications.Keywords: functional properties, high intensity ultrasound, millet protein concentrate, structural properties
Procedia PDF Downloads 2401590 Power Energy Management For A Grid-Connected PV System Using Rule-Base Fuzzy Logic
Authors: Nousheen Hashmi, Shoab Ahmad Khan
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Active collaboration among the green energy sources and the load demand leads to serious issues related to power quality and stability. The growing number of green energy resources and Distributed-Generators need newer strategies to be incorporated for their operations to keep the power energy stability among green energy resources and micro-grid/Utility Grid. This paper presents a novel technique for energy power management in Grid-Connected Photovoltaic with energy storage system under set of constraints including weather conditions, Load Shedding Hours, Peak pricing Hours by using rule-based fuzzy smart grid controller to schedule power coming from multiple Power sources (photovoltaic, grid, battery) under the above set of constraints. The technique fuzzifies all the inputs and establishes fuzzify rule set from fuzzy outputs before defuzzification. Simulations are run for 24 hours period and rule base power scheduler is developed. The proposed fuzzy controller control strategy is able to sense the continuous fluctuations in Photovoltaic power generation, Load Demands, Grid (load Shedding patterns) and Battery State of Charge in order to make correct and quick decisions.The suggested Fuzzy Rule-based scheduler can operate well with vague inputs thus doesn’t not require any exact numerical model and can handle nonlinearity. This technique provides a framework for the extension to handle multiple special cases for optimized working of the system.Keywords: photovoltaic, power, fuzzy logic, distributed generators, state of charge, load shedding, membership functions
Procedia PDF Downloads 4801589 Reform of the Law Relating to Personal Property Security
Authors: Ji Lian Yap
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This paper will critically consider developments in 2014 in relation to the law relating to security over personal property in Hong Kong. The rules governing the registration of charges under the Hong Kong Companies Ordinance will be examined. Case law relating to personal property security will also be discussed. The transplantation of the floating charge into China’s Property Law will also be considered.Keywords: personal property, security law, reform of the law, law
Procedia PDF Downloads 4251588 Multiscale Entropy Analysis of Electroencephalogram (EEG) of Alcoholic and Control Subjects
Authors: Lal Hussain, Wajid Aziz, Imtiaz Ahmed Awan, Sharjeel Saeed
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Multiscale entropy analysis (MSE) is a useful technique recently developed to quantify the dynamics of physiological signals at different time scales. This study is aimed at investigating the electroencephalogram (EEG) signals to analyze the background activity of alcoholic and control subjects by inspecting various coarse-grained sequences formed at different time scales. EEG recordings of alcoholic and control subjects were taken from the publically available machine learning repository of University of California (UCI) acquired using 64 electrodes. The MSE analysis was performed on the EEG data acquired from all the electrodes of alcoholic and control subjects. Mann-Whitney rank test was used to find significant differences between the groups and result were considered statistically significant for p-values<0.05. The area under receiver operator curve was computed to find the degree separation between the groups. The mean ranks of MSE values at all the times scales for all electrodes were higher control subject as compared to alcoholic subjects. Higher mean ranks represent higher complexity and vice versa. The finding indicated that EEG signals acquired through electrodes C3, C4, F3, F7, F8, O1, O2, P3, T7 showed significant differences between alcoholic and control subjects at time scales 1 to 5. Moreover, all electrodes exhibit significance level at different time scales. Likewise, the highest accuracy and separation was obtained at the central region (C3 and C4), front polar regions (P3, O1, F3, F7, F8 and T8) while other electrodes such asFp1, Fp2, P4 and F4 shows no significant results.Keywords: electroencephalogram (EEG), multiscale sample entropy (MSE), Mann-Whitney test (MMT), Receiver Operator Curve (ROC), complexity analysis
Procedia PDF Downloads 3761587 Investigation of the Operational Principle and Flow Analysis of a Newly Developed Dry Separator
Authors: Sung Uk Park, Young Su Kang, Sangmo Kang, Young Kweon Suh
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Mineral product, waste concrete (fine aggregates), waste in the optical field, industry, and construction employ separators to separate solids and classify them according to their size. Various sorting machines are used in the industrial field such as those operating under electrical properties, centrifugal force, wind power, vibration, and magnetic force. Study on separators has been carried out to contribute to the environmental industry. In this study, we perform CFD analysis for understanding the basic mechanism of the separation of waste concrete (fine aggregate) particles from air with a machine built with a rotor with blades. In CFD, we first performed two-dimensional particle tracking for various particle sizes for the model with 1 degree, 1.5 degree, and 2 degree angle between each blade to verify the boundary conditions and the method of rotating domain method to be used in 3D. Then we developed 3D numerical model with ANSYS CFX to calculate the air flow and track the particles. We judged the capability of particle separation for given size by counting the number of particles escaping from the domain toward the exit among 10 particles issued at the inlet. We confirm that particles experience stagnant behavior near the exit of the rotating blades where the centrifugal force acting on the particles is in balance with the air drag force. It was also found that the minimum particle size that can be separated by the machine with the rotor is determined by its capability to stay at the outlet of the rotor channels.Keywords: environmental industry, separator, CFD, fine aggregate
Procedia PDF Downloads 5951586 Separation and Characterization of Micobacterium bovis Cell Surface Lysate Antigen
Authors: Albina V. Moskvicheva, Gevorg G. Kazarian, Anna R. Valeeva, Marina A. Efimova, Malik N. Mukminov, Eduard A. Shuralev, Rustam Kh. Ravilov, Kamil S. Khaertynov
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Improving the early diagnosis of tuberculosis and solving a number of problems associated with the differential diagnosis of Mycobacterium bovis infection, nonspecific tuberculin reactions caused by sensitization of the body by non-tuberculosis mycobacteria, is urgent. The filtrates and extracts of M. bovis cell surface components are promising antigens with diagnostic potential. The purpose of this study was to isolate and characterize antigenic proteins and determine the dominant M. bovis antigens recognized by the humoral immune system. The mycobacterial cells were homogenized on FastPrep-24. Gel-filtration chromatography was used to fractionate the lysates of cell surface component extracts and proteins isolated from M. bovis culture supernatant. The separated fractions were analyzed using two-dimensional gel electrophoresis followed by determination of antigen serological activity using immunoblot with specific hyperimmune rabbit blood serum. As a result of electrophoretic separation of components by molecular weight, 23 antigen fractions were obtained. Analysis of densitograms showed that the fractions contained two zones of antigens with pronounced serological activity, corresponding to molecular weights of 28 and 21 kDa. The high serological activity of the 28 kDa antigen was established by immunoblot using hyperimmune blood sera. Separated and characterized by M. bovis specific antigen with a molecular weight of 28 kDa was added to the collection of specific marker antigens for M. bovis.Keywords: antigen, gel-filtration chromatography, immunoblot, Mycobacterium bovis
Procedia PDF Downloads 1361585 Synthesis of Flexible Mn1-x-y(CexLay)O2-δ Ultrathin-Film Device for Highly-Stable Pseudocapacitance from end-of-life Ni-MH batteries
Authors: Samane Maroufi, Rasoul Khayyam Nekouei, Sajjad Sefimofarah, Veena Sahajwalla
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The present work details a three-stage strategy based on selective purification of rare earth oxide (REOs) isolated from end-of-life nickel-metal hydride (Ni-MH) batteries leading to high-yield fabrication of defect-rich Mn1-x-y(CeₓLaᵧ)O2-δ film. In step one, major impurities (Fe and Al) were removed from a REE-rich solution. In step two, the resulting solution with trace content of Mn was further purified through electrodeposition which resulted in the synthesis of a non-stoichiometric Mn₋₁₋ₓ₋ᵧ(CeₓLaₓᵧ)O2-δ ultra-thin film, with controllable thicknesses (5-650 nm) and transmittance (~29-100%)in which Ce4+/3+ and La3+ ions were dissolved in MnO2-x lattice. Due to percolation impacts on the optoelectronic properties of ultrathin films, a representative Mn1-x-y(CexLay)O2-δ film with 86% transmittance exhibited an outstanding areal capacitance of 3.4 mF•cm-2, mainly attributed to the intercalation/de-intercalation of anionic O2- charge carriers through the atomic tunnels of the stratified Mn1-x-y(CexLay)O2-δ crystallites. Furthermore, the Mn1-x-y(CexLay)O2-δ exhibited excellent capacitance retention of ~90% after 16,000 cycles. Such stability was shown to be associated with intervalence charge transfers occurring among interstitial Ce/La cations and Mn oxidation states within the Mn₋₁₋ₓ₋ᵧ(CexLay)O2-δ structure. The energy and power densities of the transparent flexible Mn₋₁₋ₓ₋ᵧ(CexLay)O2-δ full-cell pseudocapacitor device with a solid-state electrolyte was measured to be 0.088 µWh.cm-2 and 843 µW.cm-2, respectively. These values showed insignificant changes under vigorous twisting and bending to 45-180˚, confirming these materials are intriguing alternatives for size-sensitive energy storage devices. In step three, the remaining solution purified further, that led to the formation of REOs (La, Ce, and Nd) nanospheres with ~40-50 nm diameter.Keywords: spent Ni-MH batteries, green energy, flexible pseudocapacitor, rare earth elements
Procedia PDF Downloads 1341584 Optimizing the Pair Carbon Xerogels-Electrolyte for High Performance Supercapacitors
Authors: Boriana Karamanova, Svetlana Veleva, Luybomir Soserov, Ana Arenillas, Francesco Lufrano, Antonia Stoyanova
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Supercapacitors have received a lot of research attention and are promising energy storage devices due to their high power and long cycle life. In order to developed an advanced device with significant capacity for storing charge and cheap carbon materials, efforts must focus not only on improving synthesis by controlling the morphology and pore size but also on improving electrode-electrolyte compatibility of the resulting systems. The present study examines the relationship between the surface chemistry of two activated carbon xerogels, the electrolyte type, and the electrochemical properties of supercapacitors. Activated carbon xerogels were prepared by varying the initial pH of the resorcinol-formaldehyde aqueous solution. The materials produced are physicochemical characterized by DTA/TGA, porous characterization, and SEM analysis. The carbon xerogel based electrodes were prepared by spreading over glass plate a slurry containing the carbon gel, graphite, and poly vinylidene difluoride (PVDF) binder. The layer formed was dried consecutively at different temperatures and then detached by water. After, the layer was dried again to improve its mechanical stability. The developed electrode materials and the Aquivion® E87-05S membrane (Solvay Specialty Polymers), socked in Na2SO4 as a polymer electrolyte, were used to assembly the solid-state supercapacitor. Symmetric supercapacitor cells composed by same electrodes and 1 M KOH electrolytes are also assembled and tested for comparison. The supercapacitor performances are verified by different electrochemical methods - cyclic voltammetry, galvanostatic charge/discharge measurements, electrochemical impedance spectroscopy, and long-term durability tests in neutral and alkaline electrolytes. Specific capacitances, energy, and power density, energy efficiencies, and durability were compared into studied supercapacitors. Ex-situ physicochemical analyses on the synthesized materials have also been performed, which provide information about chemical and structural changes in the electrode morphology during charge / discharge durability tests. They are discussed on the basis of electrode-electrolyte interaction. The obtained correlations could be of significance in order to design sustainable solid-state supercapacitors with high power and energy density. Acknowledgement: This research is funded by the Ministry of Education and Science of Bulgaria under the National Program "European Scientific Networks" (Agreement D01-286 / 07.10.2020, D01-78/30.03.2021). Authors gratefully acknowledge.Keywords: carbon xerogel, electrochemical tests, neutral and alkaline electrolytes, supercapacitors
Procedia PDF Downloads 1361583 Extraction and Characterization of Ethiopian Hibiscus macranthus Bast Fiber
Authors: Solomon Tilahun Desisa, Muktar Seid Hussen
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Hibiscus macranthus is one of family Malvaceae and genus Hibiscus plant which grows mainly in western part of Ethiopia. Hibiscus macranthus is the most adaptable and abundant plant in the nation, which are used as an ornamental plant often a hedge or fence plant, and used as a firewood after harvesting the stem together with the bark, and used also as a fiber for trying different kinds of things by forming the rope. However, Hibiscus macranthus plant fibre has not been commercially exploited and extracted properly. This study of work describes the possibility of mechanical and retting methods of Hibiscus macranthus fibre extraction and characterization. Hibiscus macranthus fibre is a bast fibre which obtained naturally from the stem or stalks of the dicotyledonous plant since it is a natural cellulose plant fiber. And the fibre characterized by studying its physical and chemical properties. The physical characteristics were investigated as follows, including the length of 100-190mm, fineness of 1.0-1.2Tex, diameter under X100 microscopic view 16-21 microns, the moisture content of 12.46% and dry tenacity of 48-57cN/Tex along with breaking extension of 0.9-1.6%. Hibiscus macranthus fiber productivity was observed that 12-18% of the stem out of which more than 65% is primary long fibers. The fiber separation methods prove to decrease of non-cellulose ingredients in the order of mechanical, water and chemical methods. The color measurement also shows the raw Hibiscus macranthus fiber has a natural golden color according to YID1925 and paler look under both retting methods than mechanical separation. Finally, it is suggested that Hibiscus macranthus fibre can be used for manufacturing of natural and organic crop and coffee packages as well as super absorbent, fine and high tenacity textile products.Keywords: Hibiscus macranthus, bast fiber, extraction, characterization
Procedia PDF Downloads 2101582 Vapour Liquid Equilibrium Measurement of CO₂ Absorption in Aqueous 2-Aminoethylpiperazine (AEP)
Authors: Anirban Dey, Sukanta Kumar Dash, Bishnupada Mandal
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Carbondioxide (CO2) is a major greenhouse gas responsible for global warming and fossil fuel power plants are the main emitting sources. Therefore the capture of CO2 is essential to maintain the emission levels according to the standards. Carbon capture and storage (CCS) is considered as an important option for stabilization of atmospheric greenhouse gases and minimizing global warming effects. There are three approaches towards CCS: Pre combustion capture where carbon is removed from the fuel prior to combustion, Oxy-fuel combustion, where coal is combusted with oxygen instead of air and Post combustion capture where the fossil fuel is combusted to produce energy and CO2 is removed from the flue gases left after the combustion process. Post combustion technology offers some advantage as existing combustion technologies can still be used without adopting major changes on them. A number of separation processes could be utilized part of post –combustion capture technology. These include (a) Physical absorption (b) Chemical absorption (c) Membrane separation (d) Adsorption. Chemical absorption is one of the most extensively used technologies for large scale CO2 capture systems. The industrially important solvents used are primary amines like Monoethanolamine (MEA) and Diglycolamine (DGA), secondary amines like diethanolamine (DEA) and Diisopropanolamine (DIPA) and tertiary amines like methyldiethanolamine (MDEA) and Triethanolamine (TEA). Primary and secondary amines react fast and directly with CO2 to form stable carbamates while Tertiary amines do not react directly with CO2 as in aqueous solution they catalyzes the hydrolysis of CO2 to form a bicarbonate ion and a protonated amine. Concentrated Piperazine (PZ) has been proposed as a better solvent as well as activator for CO2 capture from flue gas with a 10 % energy benefit compared to conventional amines such as MEA. However, the application of concentrated PZ is limited due to its low solubility in water at low temperature and lean CO2 loading. So following the performance of PZ its derivative 2-Aminoethyl piperazine (AEP) which is a cyclic amine can be explored as an activator towards the absorption of CO2. Vapour liquid equilibrium (VLE) in CO2 capture systems is an important factor for the design of separation equipment and gas treating processes. For proper thermodynamic modeling accurate equilibrium data for the solvent system over a wide range of temperatures, pressure and composition is essential. The present work focuses on the determination of VLE data for (AEP + H2O) system at 40 °C for various composition range.Keywords: absorption, aminoethyl piperazine, carbondioxide, vapour liquid equilibrium
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