Search results for: alternative medication
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4140

Search results for: alternative medication

1560 Software-Defined Architecture and Front-End Optimization for DO-178B Compliant Distance Measuring Equipment

Authors: Farzan Farhangian, Behnam Shakibafar, Bobda Cedric, Rene Jr. Landry

Abstract:

Among the air navigation technologies, many of them are capable of increasing aviation sustainability as well as accuracy improvement in Alternative Positioning, Navigation, and Timing (APNT), especially avionics Distance Measuring Equipment (DME), Very high-frequency Omni-directional Range (VOR), etc. The integration of these air navigation solutions could make a robust and efficient accuracy in air mobility, air traffic management and autonomous operations. Designing a proper RF front-end, power amplifier and software-defined transponder could pave the way for reaching an optimized avionics navigation solution. In this article, the possibility of reaching an optimum front-end to be used with single low-cost Software-Defined Radio (SDR) has been investigated in order to reach a software-defined DME architecture. Our software-defined approach uses the firmware possibilities to design a real-time software architecture compatible with a Multi Input Multi Output (MIMO) BladeRF to estimate an accurate time delay between a Transmission (Tx) and the reception (Rx) channels using the synchronous scheduled communication. We could design a novel power amplifier for the transmission channel of the DME to pass the minimum transmission power. This article also investigates designing proper pair pulses based on the DO-178B avionics standard. Various guidelines have been tested, and the possibility of passing the certification process for each standard term has been analyzed. Finally, the performance of the DME was tested in the laboratory environment using an IFR6000, which showed that the proposed architecture reached an accuracy of less than 0.23 Nautical mile (Nmi) with 98% probability.

Keywords: avionics, DME, software defined radio, navigation

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1559 Raman, Atomic Force Microscopy and Mass Spectrometry for Isotopic Ratios Methods Used to Investigate Human Dentine and Enamel

Authors: Nicoleta Simona Vedeanu, Rares Stiufiuc, Dana Alina Magdas

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A detailed knowledge of the teeth structure is mandatory to understand and explain the defects and the dental pathology, but especially to take a correct decision regarding dental prophylaxis and treatment. The present work is an alternative study to the traditional investigation methods used in dentistry, a study based on the use of modern, sensitive physical methods to investigate human enamel and dentin. For the present study, several teeth collected from patients of different ages were used for structural and dietary investigation. The samples were investigated by Raman spectroscopy for the molecular structure analysis of dentin and enamel, atomic force microscopy (AFM) to view the dental topography at the micrometric size and mass spectrometry for isotopic ratios as a fingerprint of patients’ personal diet. The obtained Raman spectra and their interpretation are in good correlation with the literature and may give medical information by comparing affected dental structures with healthy ones. AFM technique gave us the possibility to study in details the dentin and enamel surface to collect information about dental hardness or dental structural changes. δ¹³C values obtained for the studied samples can be classified in C4 category specific to young people and children diet (sweets, cereals, juices, pastry). The methods used in this attempt furnished important information about dentin and enamel structure and dietary habits and each of the three proposed methods can be extended at a larger level in the study of the teeth structure.

Keywords: AFM, dentine, enamel, Raman spectroscopy

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1558 The Impact of Pediatric Cares, Infections and Vaccines on Community and People’s Lives

Authors: Nashed Atef Nashed Farag

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Introduction: Reporting adverse events following vaccination remains a challenge. WHO has mandated pharmacovigilance centers around the world to submit Adverse Events Following Immunization (AEFI) reports from different countries to a large electronic database of adverse drug event data called Vigibase. Despite sufficient information about AEFIs on Vigibase, they are not available to the general public. However, the WHO has an alternative website called VigiAccess, an open-access website that serves as an archive for reported adverse reactions and AEFIs. The aim of the study was to establish a reporting model for a number of commonly used vaccines in the VigiAccess system. Methods: On February 5, 2018, VigiAccess comprehensively searched for ESSI reports on the measles vaccine, oral polio vaccine (OPV), yellow fever vaccine, pneumococcal vaccine, rotavirus vaccine, meningococcal vaccine, tetanus vaccine, and tuberculosis vaccine (BCG). These are reports from all pharmacovigilance centers around the world since they joined the WHO Drug Monitoring Program. Results: After an extensive search, VigiAccess found 9,062 AEFIs from the measles vaccine, 185,829 AEFIs from the OPV vaccine, 24,577 AEFIs from the yellow fever vaccine, 317,208 AEFIs from the pneumococcal vaccine, 73,513 AEFIs from the rotavirus vaccine, and 145,447 AEFIs from meningococcal cal vaccine, 22,781 EI FI vaccines against tetanus and 35,556 BCG vaccines against AEFI. Conclusion: The study found that among the eight vaccines examined, pneumococcal vaccines were associated with the highest number of AEFIs, while measles vaccines were associated with the fewest AEFIs.

Keywords: surgical approach, anatomical approach, decompression, axillary nerve, quadrangular space adverse events following immunization, cameroon, COVID-19 vaccines, nOPV, ODK vaccines, adverse reactions, VigiAccess, adverse event reporting

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1557 The Optimization of the Parameters for Eco-Friendly Leaching of Precious Metals from Waste Catalyst

Authors: Silindile Gumede, Amir Hossein Mohammadi, Mbuyu Germain Ntunka

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Goal 12 of the 17 Sustainable Development Goals (SDGs) encourages sustainable consumption and production patterns. This necessitates achieving the environmentally safe management of chemicals and all wastes throughout their life cycle and the proper disposal of pollutants and toxic waste. Fluid catalytic cracking (FCC) catalysts are widely used in the refinery to convert heavy feedstocks to lighter ones. During the refining processes, the catalysts are deactivated and discarded as hazardous toxic solid waste. Spent catalysts (SC) contain high-cost metal, and the recovery of metals from SCs is a tactical plan for supplying part of the demand for these substances and minimizing the environmental impacts. Leaching followed by solvent extraction, has been found to be the most efficient method to recover valuable metals with high purity from spent catalysts. However, the use of inorganic acids during the leaching process causes a secondary environmental issue. Therefore, it is necessary to explore other alternative efficient leaching agents that are economical and environmentally friendly. In this study, the waste catalyst was collected from a domestic refinery and was characterised using XRD, ICP, XRF, and SEM. Response surface methodology (RSM) and Box Behnken design were used to model and optimize the influence of some parameters affecting the acidic leaching process. The parameters selected in this investigation were the acid concentration, temperature, and leaching time. From the characterisation results, it was found that the spent catalyst consists of high concentrations of Vanadium (V) and Nickel (Ni); hence this study focuses on the leaching of Ni and V using a biodegradable acid to eliminate the formation of the secondary pollution.

Keywords: eco-friendly leaching, optimization, metal recovery, leaching

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1556 Use of High Hydrostatic Pressure as an Alternative Preservation Method in Camels Milk

Authors: Fahad Aljasass, Hamza Abu-Tarboush, Salah Aleid, Siddig Hamad

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The effects of different high hydrostatic pressure treatments on the shelf life of camel’s milk were studied. Treatments at 300 to 350 MPa for 5 minutes at 40°C reduced microbial contamination to levels that prolonged the shelf life of refrigerated (3° C) milk up to 28 days. The treatment resulted in a decrease in the proteolytic activity of the milk. The content of proteolytic enzymes in the untreated milk sample was 4.23 µM/ml. This content decreased significantly to 3.61 µM/ml when the sample was treated at 250 MPa. Treatment at 300 MPa decreased the content to 3.90 which was not significantly different from the content of the untreated sample. The content of the sample treated at 350 MPa dropped to 2.98 µM/ml which was significantly lower than the contents of all other treated and untreated samples. High pressure treatment caused a slight but statistically significant increase in the pH of camel’s milk. The pH of the untreated sample was 6.63, which increased significantly to 6.70, in the samples treated at 250 and 350 MPa, but insignificantly in the sample treated at 300 MPa. High pressure treatment resulted in some degree of milk fat oxidation. The thiobarbituric acid (TBA) value of the untreated sample was 0.86 mg malonaldehyde/kg milk. This value remained unchanged in the sample treated at 250 MPa, but then it increased significantly to 1.25 and 1.33 mg/kg in the samples treated at 300 and 350 MPa, respectively. High pressure treatment caused a small increase in the greenness (a* value) of camel’s milk. The value of a* was reduced from -1.17 for the untreated sample to -1.26, -1.21 and -1.30 for the samples treated at 250, 300 and 350 MPa, respectively. Δa* at the 250 MPa treatment was -0.09, which then decreased to -0.04 at the 300 MPa treatment to increase again to -0.13 at the 350 MPa treatment. The yellowness (b* value) of camel’s milk increased significantly as a result of high pressure treatment. The b* value of the untreated sample was 1.40, this value increased to 2.73, 2.31 and 2.18 after treatments at 250, 300 and 350 MPa, respectively. The Δb* value was +1.33 at the treatment 250 MPa, decreased to +0.91 at 300 MPa and further to +0.78 at 350 MPa. The pressure treatment caused slight effect on color, slight decrease in protease activity and a slight increase in the oxidation products of lipids.

Keywords: high hydrostatic pressure, camel’s milk, mesophilic aerobic bacteria, clotting, protease

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1555 Planning for Sustainability in the Built Environment

Authors: Adedayo Jeremiah Adeyekun, Samuel Oluwagbemiga Ishola

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This paper aimed to identify the significance of sustainability in the built environment, the economic and environmental importance to building and construction projects. Sustainability in the built environment has been a key objective of research over the past several decades. Sustainability in the built environment requires reconciliation between economic, environmental and social impacts of design and planning decisions made during the life cycle of a project from inception to termination. Planning for sustainability in the built environment needs us to go beyond our individual disciplines to consider the variety of economic, social and environmental impacts of our decisions in the long term. A decision to build a green residential development in an isolated location may pass some of the test of sustainability through its reduction in stormwater runoff, energy efficiency, and ecological sustainability in the building, but it may fail to be sustainable from a transportation perspective. Sustainability is important to the planning, design, construction, and preservation of the built environment; because it helps these activities reflect multiple values and considerations. In fact, the arts and sciences of the built environment have traditionally integrated values and fostered creative expression, capabilities that can and should lead the sustainability movement as society seeks ways to live in dynamic balance with its own diverse needs and the natural world. This research aimed to capture the state-of-the-art in the development of innovative sustainable design and planning strategies for building and construction projects. Therefore, there is a need for a holistic selection and implication approach for identifying potential sustainable strategies applicable to a particular project and evaluating the overall life cycle impact of each alternative by accounting for different applicable impacts and making the final selection among various viable alternatives.

Keywords: sustainability, built environment, planning, design, construction

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1554 Experimental Investigation of Mechanical Friction Influence in Semi-Hydraulic Clutch Actuation System Over Mileage

Authors: Abdul Azarrudin M. A., Pothiraj K., Kandasamy Satish

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In the current automobile scenario, there comes a demand on more sophistication and comfort drive feel on passenger segments. The clutch pedal effort is one such customer touch feels in manual transmission vehicles, where the driver continuous to operate the clutch pedal in his entire the driving maneuvers. Hence optimum pedal efforts at green condition and over mileage to be ensured for fatigue free the driving. As friction is one the predominant factor and its tendency to challenge the technicality by causing the function degradation. One such semi-hydraulic systems shows load efficiency of about 70-75% over lifetime only due to the increase in friction which leads to the increase in pedal effort and cause fatigue to the vehicle driver. This work deals with the study of friction with different interfaces and its influence in the fulcrum points over mileage, with the objective of understanding the trend over mileage and determining the alternative ways of resolving it. In that one way of methodology is the reduction of friction by experimental investigation of various friction reduction interfaces like metal-to-metal interface and it has been tried out and is detailed further. Also, the specific attention has been put up considering the fulcrum load and its contact interfaces to move on with this study. The main results of the experimental data with the influence of three different contact interfaces are being presented with an ultimate intention of ending up into less fatigue with longer consistent pedal effort, thus smoothens the operation of the end user. The Experimental validation also has been done through rig-level test setup to depict the performance at static condition and in-parallel vehicle level test has also been performed to record the additional influences if any.

Keywords: automobile, clutch, friction, fork

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1553 Solar PV System for Automatic Guideway Transit (AGT) System in BPSU Main Campus

Authors: Nelson S. Andres, Robert O. Aguilar, Mar O. Tapia, Meeko C. Masangcap, John Denver Catapang, Greg C. Mallari

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This study focuses on exploring the possibility of using solar PV as an alternative for generating electricity to electrify the AGT System installed in BPSU Main Campus instead of using the power grid. The output of this study gives BPSU the option to invest on solar PV system to pro-actively respond to one of UN’s Sustainable Development Goals of having reliable, sustainable and modern energy sources to reduce energy pollution and climate change impact in the long run. Thus, this study covers the technical as well as the financial studies, which BPSU can also be used to outsource funding from different government agencies. For this study, the electrical design and requirements of the on-going DOST AGT system project are carefully considered. In the proposed design, the AGT station has installed with a rechargeable battery system where the energy harnessed by the solar PV panels installed on the rooftop of the station/NCEA building shall be directed to. The solar energy is then directly supplied to the electric double-layer capacitors (EDLC's) batteries and thus transmitted to other types of equipment in need. When the AGT is not in use, the harnessed energy may be used by NCEA building, thus, lessening the energy consumption of the building from the grid. The use of solar PV system with EDLC is compared with the use of an electric grid for the purpose of electrifying the AGT or the NCEA building (when AGT is not in use). This is to figure how much solar energy are accumulated by the solar PV to accommodate the need for coaches’ motors, lighting, air-conditioning units, door sensor, panel display, etc. The proposed PV Solar design, as well as the data regarding the charging and discharging of batteries and the power consumption of all AGT components, are simulated for optimization, analysis and validation through the use of PVSyst software.

Keywords: AGT, Solar PV, railway, EDLC

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1552 Challenges to Reaching Higher Education in Developing Countries

Authors: Suhail Shersad

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Introduction In developing countries, the access to higher education for the lower socioeconomic strata is very poor at less than 0.05%. The challenges faced by prospective students in these circumstances to pursue higher education have been explored through direct interaction with them and their families in urban slums of New Delhi. This study included evaluation of the demographics, social indices, expectations and perceptions of selected communities. Results The results show that the poor life expectancy, low exposure to technology, lack of social infrastructure and poor sanitary conditions have reduced their drive for academic achievements. This is despite a good level of intelligence and critical thinking skills among these students. The perception of the community including parents shows that despite their desire to excel, there are too may roadblocks to achieving a fruitful professional life for the next generation. Discussion The prerequisites of higher education may have to be revisited to be more inclusive of socially handicapped students. The knowledge, skills and attributes required for higher education system should form the baseline for creating a roadmap for higher secondary education suited for local needs. Conventional parameters like marks and grading have to be re-looked so that life skills and vocational training form part of the core curriculum. Essential skills should be incorporated at an earlier age, providing an alternative pathway for such students to join higher education. Conclusion: There is a need to bridge the disconnect that exists between higher education planning, the needs of the concerned cohorts and the existing higher secondary education. The variables that contribute to making such a decision have to be examined further. Keywords: prerequisites of higher education, social mobility, society expectations, access to higher education

Keywords: access to higher education, prerequisites of higher education, society expectations, social mobility

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1551 Modifying Cardiometabolic Disease Risk Factors in Urban Primary School Children: Three Different Exercise Interventions

Authors: Anneke Van Biljon

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Background: Exercise is a primary form of preventing and improving cardiometabolic disease risk factors; however specific exercise variables and their associated health benefits in children are inconclusive. A preliminary study revealed that different exercise variables may improve particular cardiometabolic health benefits. Objectives: This study further investigated the specific cardiometabolic health benefits associated with three isocaloric exercise interventions set at different intensities. Methods: Hundred-and-twenty (n = 120) participants between the ages of 10 – 14 years old were assigned to four different study groups 1. High intensity interval training (HIIT) at > 80% MHR 2. Moderate intensity continuous training (MICT) at 65% – 70% MHR 3. Alternative intensities (ALT) of HIIT and MICT 4. Control group. Exercise interventions were designed to generate isocaloric workloads of ~154.77 kcal per session, three times per week for five weeks. The one-way ANOVA test established comparisons between group means. Post hoc tests were calculated to determine specific group differences. Results: Although, all exercise groups improved cardiometabolic health, the MICT group showed greater improvements in fasting glucose (-9.30%), whereas cardiorespiratory fitness increased most by 31.33% (p = 0.000) within the HIIT group. Finally, ALT group recorded overall superior and additional cardiometabolic health benefits compared with both MICT and HIIT groups. Conclusion: The findings of this study indicate that superior benefits may be elicited when combining and alternating MICT and HIIT. These results provide specific exercise recommendations for achieving optimal and substantial cardiometabolic health benefits in children which will contribute towards achieving the health-related Sustainable Development Goals for 2030.

Keywords: cardiometabolic disease risk factors, exercise, pediatrics, interventions

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1550 The Terminology of Mandatory Mediation on Commercial Disputes in Türkiye and the Differences from England and Wales’s Approaches

Authors: Sevgi Karaca

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Since December 6, 2018, mediation has become mandatory for commercial disputes under the Turkish Commercial Code. Mandatory mediation became one of the “causes of action”, and being compulsory means starting the mediation process before going to court. As it contemplates looking at “the causes of the action”, the terminology may lead to misinterpretation of the core of the phrases. However, the terms pertain to a prerequisite for starting the lawsuit. The court will examine failure to comply with such requirements, and the case will be dismissed without further action. Türkiye’s use of obligatory mediation is highly unusual. It is neither judge-led nor judge-assisted mediation but rather a mediation conducted outside of court with the participation of a third party (mediators). What distinguishes it is the incorporation of obligatory mediation into the causes of actions listed in the Code of Civil Procedure. Being one of the causes of action in a legal case implies that the absence of any of them may result in the procedural dismissal of the case without any further action. The case must be presented to the mediator first, and if the parties are unable to reach an agreement, they must deliver the results of the mediation session. Other than submitting the minutes, parties are ineligible to file a lawsuit. However, despite a lengthy history of use in England and Wales, there are considerable reservations about making mediation mandatory. The Civil Procedure Code does not explicitly mention making mediation mandatory. For the time being, there is no Mediation Code, and case law limits the growth of obligatory mediation. Some renowned judges voiced their desire to re-evaluate the notion of required mediation, prompting the Civil Justice Council to release a study in 2021 on the significance of amending case law and the high value of mandatory mediation. By contrasting the approaches to mandatory mediation in England and Wales, the study will investigate the method of controlled mandatory mediation and its effects on the success of mediation in Türkiye.

Keywords: alternative dispute resolution, case law, cause of action, litigation process, mandatory mediation

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1549 Transesterification of Waste Cooking Oil for Biodiesel Production Using Modified Clinoptilolite Zeolite as a Heterogeneous Catalyst

Authors: D. Mowla, N. Rasti, P. Keshavarz

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Reduction of fossil fuels sources, increasing of pollution gases emission, and global warming effects increase the demand of renewable fuels. One of the main candidates of alternative fuels is biodiesel. Biodiesel limits greenhouse gas effects due to the closed CO2 cycle. Biodiesel has more biodegradability, lower combustion emissions such as CO, SOx, HC, PM and lower toxicity than petro diesel. However, biodiesel has high production cost due to high price of plant oils as raw material. So, the utilization of waste cooking oils (WCOs) as feedstock, due to their low price and disposal problems reduce biodiesel production cost. In this study, production of biodiesel by transesterification of methanol and WCO using modified sodic potassic (SP) clinoptilolite zeolite and sodic potassic calcic (SPC) clinoptilolite zeolite as heterogeneous catalysts have been investigated. These natural clinoptilolite zeolites were modified by KOH solution to increase the site activity. The optimum biodiesel yields for SP clinoptilolite and SPC clinoptilolite were 95.8% and 94.8%, respectively. Produced biodiesel were analyzed and compared with petro diesel and ASTM limits. The properties of produced biodiesel confirm well with ASTM limits. The density, kinematic viscosity, cetane index, flash point, cloud point, and pour point of produced biodiesel were all higher than petro diesel but its acid value was lower than petro diesel. Finally, the reusability and regeneration of catalysts were investigated. The results indicated that the spent zeolites cannot be reused directly for the transesterification, but they can be regenerated easily and can obtain high activity.

Keywords: biodiesel, renewable fuel, transesterification, waste cooking oil

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1548 Pretreatment of Aquatic Weed Typha latifolia with Sodium Bisulphate for Enhanced Acid and Enzyme Hydrolysis for Production of Xylitol and Bioethanol

Authors: Jyosthna Khanna Goli, Shaik Naseeruddin, Hameeda Bee

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Employing lignocellulosic biomass in fermentative production of xylitol and bioethanol is gaining interest as it is renewable, cheap, and abundantly available. Xylitol is a polyol, gaining its importance in the food and pharmacological industry due to its low calorific value and anti-cariogenic nature. Bioethanol from lignocellulosic biomass is widely accepted as an alternative fuel for transportation with reduced CO₂ emissions, thus reducing the greenhouse effect. Typha latifolia, an aquatic weed, was found to be promising lignocellulosic substrate as it posses a high amount of sugars and does not compete with arable lands and interfere with food and feed competition. In the present study, xylose from hemicellulosic fraction of typha is converted to xylitol by isolate Jfh5 (Candida. tropicalis) and cellulose part to ethanol using Saccharomyces cerevisiaeVS3. Initially, alkali pretreatment of typha using sodium hydroxide, potassium hydroxide, ammonium hydroxide, calcium hydroxide, sodium bisulphate and sodium dithionate for overnight (18h) at room temperature (28 ± 2°C), resulted in maximum delignification of 75% with 2% (v/v) sodium bisulphate. Later, pretreated biomass was subjected to acid hydrolysis with 1%, 1.5%, 2%, and 3% H₂SO₄ at 110 °C and 121°C for 30 and 60 min, respectively. 2% H₂SO₄ at 121°C for 60 min was found to release 13.5 g /l sugars, which on detoxification and fermentation produced 8.1g/l xylitol with yield and productivity of 0.65g/g and 0.112g/l/h respectively. Further enzymatic hydrolysis of the residual substrate obtained after acid hydrolysis released 11g/l sugar, which on fermentation with VS3 produced 4.9g/l ethanol with yield and productivity of 0.22g/g and 0.136g/l/h respectively.

Keywords: delignification, xylitol, bioethanol, acid hydrolysis, enzyme hydrolysis

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1547 Development of CaO-based Sorbents Applied to Sorption Enhanced Steam Reforming Processes

Authors: P. Comendador, I. Garcia, S. Orozco, L. Santamaria, M. Amutio, G. Lopez, M. Olazar

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In situ CO₂ capture in steam reforming processes has been studied in the last years as an alternative for increasing H₂ yields and H₂ purity in the product stream. For capturing the CO₂ at the reforming conditions, CaO-based sorbents are usually employed due to their properties at high temperature, low cost and high availability. However, the challenge is to develop high-capacity (gCO₂/gsorbent) materials that retain their capacity over cycles of operation. Besides, since the objective is to capture the CO₂ generated in situ, another key aspect is the sorption dynamics, which means that, in order to efficiently use the sorbent, it has to capture the CO₂ at a rate equal to or higher than the generation rate. In this work, different CaO-based materials have been prepared to aim at meeting these criteria. First, and by using the wet mixing method, different inert materials (Mg, Ce and Al) were combined with CaO. Second, and with the inert material selected (Mg), the effect of its concentration in the final material was studied. Transversally, the calcination temperature was also evaluated. It was determined that the wet mixing method is a simple procedure suitable for the preparation of CaO sorbents mixed with inert materials. The materials prepared by mixing the CaO with Mg have shown satisfactory anti-sintering properties and adequate sorption kinetics for their application in steam reforming processes. Regarding the concentration of Mg in the solid, it was concluded that high values contribute to the stability but at the expense of losing sorption capacity. Finally, it was observed that high calcination temperatures negatively affected the sorption properties of the final materials due to the decrease in the pore volume and the specific surface area.

Keywords: calcination temperature effect, CO₂ capture, Mg-Ce-Al stabilizers, Mg varying concentration effect, Sorbent stabilization

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1546 Rational Design and Synthesis of 2D/3D Conjugated Porous Polymers via Facile and 'Greener' Direct Arylation Polycondensation

Authors: Hassan Bohra, Mingfeng Wang

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Conjugated porous polymers (CPPs) are amorphous, insoluble and highly robust organic semiconductors that have been largely synthesized by traditional transition-metal catalyzed reactions. The distinguishing feature of CPP materials is that they combine microporosity and high surface areas with extended conjugation, making them ideal for versatile applications such as separation, catalysis and energy storage. By applying a modular approach to synthesis, chemical and electronic properties of CPPs can be tailored for specific applications making these materials economical alternatives to inorganic semiconductors. Direct arylation - an environmentally benign alternative to traditional polymerization reactions – is one such reaction that extensively over the last decade for the synthesis of linear p-conjugated polymers. In this report, we present the synthesis and characterization of a new series of robust conjugated porous polymers synthesized by facile direct arylation polymerization of thiophene-flanked acceptor building blocks with multi-brominated aryls with different geometries. We observed that the porosities and morphologies of the polymers are determined by the chemical structure of the aryl bromide used. Moreover, good control of the optical bandgap in the range 2.53 - 1.3 eV could be obtained by using different building blocks. Structure-property relationships demonstrated in this study suggest that direct arylation polymerization is an attractive synthetic tool for the rational design of porous organic materials with tunable photo-physical properties for applications in photocatalysis, energy storage and conversion.

Keywords: direct arylation, conjugated porous polymers, triazine, photocatalysis

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1545 Wellbeing Warriors: A Randomized Controlled Trial Examining the Effect of Martial Arts Training on Mental Health Outcomes

Authors: Brian Moore, Stuart Woodcock, Dean Dudley

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Mental health problems have significant social and economic consequences; however, many individuals do not seek traditional assistance for mental health difficulties. Martial arts training may provide an inexpensive alternative to traditional psychological therapy. While limited research has suggested martial arts training may be an efficacious intervention, the validity and reliability of this are questionable given the small number of relevant studies and other methodological problems. The study examined the effects of 10-week martial arts-based psycho-social intervention which was evaluated using a randomized controlled trial. The intervention was delivered to 283 secondary school students, aged between 12-14 years, who were recruited from government and catholic secondary schools in New South Wales, Australia. The intervention was delivered in a group format onsite at participating schools and had an intervention dose of 10 x 50-60 minute sessions, once per week for 10 weeks. Data were collected at baseline, post-intervention, and 12-week follow-up. Results found a consistent pattern for strength based wellbeing outcomes. All primary and secondary measures relating to resilience and self-efficacy improved for the intervention group and declined for the control group. As these findings were derived from a robust design and rigorous evaluation, they provide valid and reliable evidence that martial arts-based psycho-social interventions can be considered as an efficacious method of improving strength and wellbeing outcomes.

Keywords: martial arts, mental health, resilience, self-efficacy

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1544 An Agent-Based Model of Innovation Diffusion Using Heterogeneous Social Interaction and Preference

Authors: Jang kyun Cho, Jeong-dong Lee

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The advent of the Internet, mobile communications, and social network services has stimulated social interactions among consumers, allowing people to affect one another’s innovation adoptions by exchanging information more frequently and more quickly. Previous diffusion models, such as the Bass model, however, face limitations in reflecting such recent phenomena in society. These models are weak in their ability to model interactions between agents; they model aggregated-level behaviors only. The agent based model, which is an alternative to the aggregate model, is good for individual modeling, but it is still not based on an economic perspective of social interactions so far. This study assumes the presence of social utility from other consumers in the adoption of innovation and investigates the effect of individual interactions on innovation diffusion by developing a new model called the interaction-based diffusion model. By comparing this model with previous diffusion models, the study also examines how the proposed model explains innovation diffusion from the perspective of economics. In addition, the study recommends the use of a small-world network topology instead of cellular automata to describe innovation diffusion. This study develops a model based on individual preference and heterogeneous social interactions using utility specification, which is expandable and, thus, able to encompass various issues in diffusion research, such as reservation price. Furthermore, the study proposes a new framework to forecast aggregated-level market demand from individual level modeling. The model also exhibits a good fit to real market data. It is expected that the study will contribute to our understanding of the innovation diffusion process through its microeconomic theoretical approach.

Keywords: innovation diffusion, agent based model, small-world network, demand forecasting

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1543 Male Bodies and Philosophy of Sexual Difference: A Sketch for an Impossible 'Becoming-Man'

Authors: Ovidiu Anemtoaicei

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This paper offers a possible answer to the question of what it means to think about men and masculinities through the philosophy of sexual difference as developed by Luce Irigaray, employing Gilles Deleuze’s concept of 'critique' and arguing, at the same time, for a concept of 'becoming-man' as an expression of this answer. First, while examining the nature of the role of male bodies underlying the theorizing of men and masculinities in the field of the Critical Studies of Men and Masculinities, the paper argues for a turn to sexual difference theory as an answer to the 'gap' between the representations on male bodies and their participation in thought and masculine subjective production. Secondly, sharing Luce Irigaray’s critique of Western thought, the paper explores alternative morphological bodily 'locations' for rethinking male imaginary in relation to male embodiments, on the one hand, and in relation to the maternal and the feminine, on the other hand. Thirdly, the paper develops the idea that a phenomenologically-influenced approach towards male bodies might be productive, especially when thought through Irigaray’s sexual difference as a relational and experiential ontology. Finally, while showing that Irigaray and Deleuze share a similar critique of Western philosophical thought and of the masculine historical subject, it proposes a rethinking of the concept of 'becoming-man' as an assemblage meeting between Irigaray’s theory of sexual difference and Deleuze and Guattari’s nomadologic project, as a possibility of thinking change in men’s masculine subjective constitution in relation to both women and other men. As far as the ethical implications of such rethinking are concerned, the paper urges for the cultivation of a masculine culture of stepping back and its constitutive political, social and cultural practices so as to make possible the construction of new spaces that would allow for the becoming of at least two subjects based on the respect for their differences.

Keywords: feminist philosophy, male bodies, masculinities, phenomenology, sexual difference

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1542 Visual Outcome After 360-Degree Retinectomy in Total Rhegmatogenous Retinal Detachment with Advanced Proliferative Vitreoretinopathy: A Case Series

Authors: Andriati Nadhilah Widyarini, Ezra Margareth

Abstract:

Introduction: Rhegmatogenous retinal detachment is a condition where there’s a break in the retina, which allows the vitreous to directly enter the subretinal space. Proliferative vitreoretinopathy (PVR) may develop due to this condition and can result in a new break, which could cause traction on the previously detached retina. Various methods of therapy can be done to treat this complication. Case: This case series involved 2 eyes of 2 patients who had total retinal detachment with advanced PVR. Pars plana vitrectomy was performed, and a 360-degree retinectomy procedure with perfluorocarbon liquid usage was done. This was followed by endo laser retinopexy to surround the border of retinectomy. 5000 cs silicone oil was used in 1 eye, whereas 12% of perfluoropropane gas was used in the other eye as a tamponade. These procedures were performed with meticulous attention to prevent any fluid from entering the subretinal space. Postoperative examination showed attachment of the retina and improvement of the patient’s visual acuity. Both eyes’ intraocular pressure was in the normal range. One eye developed retinal displacement, but no other complications occurred. Discussion: Rhegmatogenous retinal detachment with advanced PVR is a complex situation for vitreoretinal surgeons. PVR is characterized by the growth and migration of preretinal or subretinal membranes. PVR is the most common cause of retinal reattachment failure. A 360-degree retinectomy is an alternative surgical method to overcome this condition. Objectives of this procedure are releasing retinal traction caused by PVR, reducing the recurrence rate of PVR, and reattaching the retina to the pigment epithelial surface. Conclusion: 360-degree retinectomy provides satisfactory retinal reattachment and visual outcome improvement in rhegmatogenous retinal detachment with advanced PVR.

Keywords: RRD, retinectomy, pars plana, advanced PVR

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1541 Understanding Tactical Urbanisms in Derelict Areas

Authors: Berna Yaylalı, Isin Can Traunmüller

Abstract:

This paper explores the emergent bottom-up practices in the fields of architecture and urban design within comparative perspectives of two cities. As a temporary, easily affordable intervention that gives the possibility of transforming neglected spaces into vibrant public spaces, tactical urbanism, together with creative place-making strategies, presents alternative ways of creating sustainable developments in derelict and underused areas. This study examines the potential of social and physical developments through a reading of case studies of two creative spatial practices: a pop-up garden transformed from an unused derelict space in Favoriten, Vienna, and an urban community garden in Kuzguncuk, Istanbul. Two cities are chosen according to their multicultural population and diversity. Istanbul was selected as a design city by UNESCO Creative Cities Network in 2017, and Vienna was declared an open and livable city by its local government. This research will use media archives and reports, interviews with locals and local governments, site observations, and visual recordings as methods to provide a critical reading on creative public spaces from the view of local users in these neighborhoods. Reflecting on these emergent ways, this study aims at discussing the production process of tactile urbanism with the practices of locals and the decision-making process with cases from İstanbul and Vienna. The comparison between their place-making strategies in tactical urbanism will give important insights for future developments.

Keywords: creative city, tactical urbanism, neglected area, public space

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1540 Impact of Silicon Surface Modification on the Catalytic Performance Towards CO₂ Conversion of Cu₂S/Si-Based Photocathodes

Authors: Karima Benfadel, Lamia Talbi, Sabiha Anas Boussaa, Afaf Brik, Assia Boukezzata, Yahia Ouadah, Samira Kaci

Abstract:

In order to prevent global warming, which is mainly caused by the increase in carbon dioxide levels in the atmosphere, it is interesting to produce renewable energy in the form of chemical energy by converting carbon dioxide into alternative fuels and other energy-dense products. Photoelectrochemical reduction of carbon dioxide to value-added products and fuels is a promising and current method. The objective of our study is to develop Cu₂S-based photoélectrodes, in which Cu₂S is used as a CO₂ photoelectrocatalyst deposited on nanostructured silicon substrates. Cu₂S thin layers were deposited using the chemical bath deposition (CBD) technique. Silicon nanowires and nanopyramids were obtained by alkaline etching. SEM and UV-visible spectroscopy was used to analyse the morphology and optical characteristics. By using a potentiostat station, we characterized the photoelectrochemical properties. We performed cyclic voltammetry in the presence and without CO₂ purging as well as linear voltammetry (LSV) in the dark and under white light irradiation. We perform chronoamperometry to study the stability of our photocathodes. The quality of the nanowires and nanopyramids was visible in the SEM images, and after Cu₂S deposition, we could see how the deposition was distributed over the textured surfaces. The inclusion of the Cu₂S layer applied on textured substrates significantly reduces the reflectance (R%). The catalytic performance towards CO₂ conversion of Cu₂S/Si-based photocathodes revealed that the texturing of the silicon surface with nanowires and pyramids has a better photoelectrochemical behavior than those without surface modifications.

Keywords: CO₂ conversion, Cu₂S photocathode, silicone nanostructured, electrochemistry

Procedia PDF Downloads 78
1539 Artificial Intelligence Based Predictive Models for Short Term Global Horizontal Irradiation Prediction

Authors: Kudzanayi Chiteka, Wellington Makondo

Abstract:

The whole world is on the drive to go green owing to the negative effects of burning fossil fuels. Therefore, there is immediate need to identify and utilise alternative renewable energy sources. Among these energy sources solar energy is one of the most dominant in Zimbabwe. Solar power plants used to generate electricity are entirely dependent on solar radiation. For planning purposes, solar radiation values should be known in advance to make necessary arrangements to minimise the negative effects of the absence of solar radiation due to cloud cover and other naturally occurring phenomena. This research focused on the prediction of Global Horizontal Irradiation values for the sixth day given values for the past five days. Artificial intelligence techniques were used in this research. Three models were developed based on Support Vector Machines, Radial Basis Function, and Feed Forward Back-Propagation Artificial neural network. Results revealed that Support Vector Machines gives the best results compared to the other two with a mean absolute percentage error (MAPE) of 2%, Mean Absolute Error (MAE) of 0.05kWh/m²/day root mean square (RMS) error of 0.15kWh/m²/day and a coefficient of determination of 0.990. The other predictive models had prediction accuracies of MAPEs of 4.5% and 6% respectively for Radial Basis Function and Feed Forward Back-propagation Artificial neural network. These two models also had coefficients of determination of 0.975 and 0.970 respectively. It was found that prediction of GHI values for the future days is possible using artificial intelligence-based predictive models.

Keywords: solar energy, global horizontal irradiation, artificial intelligence, predictive models

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1538 Development of a Sensitive Electrochemical Sensor Based on Carbon Dots and Graphitic Carbon Nitride for the Detection of 2-Chlorophenol and Arsenic

Authors: Theo H. G. Moundzounga

Abstract:

Arsenic and 2-chlorophenol are priority pollutants that pose serious health threats to humans and ecology. An electrochemical sensor, based on graphitic carbon nitride (g-C₃N₄) and carbon dots (CDs), was fabricated and used for the determination of arsenic and 2-chlorophenol. The g-C₃N₄/CDs nanocomposite was prepared via microwave irradiation heating method and was dropped-dried on the surface of the glassy carbon electrode (GCE). Transmission electron microscopy (TEM), X-ray diffraction (XRD), photoluminescence (PL), Fourier transform infrared spectroscopy (FTIR), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) were used for the characterization of structure and morphology of the nanocomposite. Electrochemical characterization was done by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The electrochemical behaviors of arsenic and 2-chlorophenol on different electrodes (GCE, CDs/GCE, and g-C₃N₄/CDs/GCE) was investigated by differential pulse voltammetry (DPV). The results demonstrated that the g-C₃N₄/CDs/GCE significantly enhanced the oxidation peak current of both analytes. The analytes detection sensitivity was greatly improved, suggesting that this new modified electrode has great potential in the determination of trace level of arsenic and 2-chlorophenol. Experimental conditions which affect the electrochemical response of arsenic and 2-chlorophenol were studied, the oxidation peak currents displayed a good linear relationship to concentration for 2-chlorophenol (R²=0.948, n=5) and arsenic (R²=0.9524, n=5), with a linear range from 0.5 to 2.5μM for 2-CP and arsenic and a detection limit of 2.15μM and 0.39μM respectively. The modified electrode was used to determine arsenic and 2-chlorophenol in spiked tap and effluent water samples by the standard addition method, and the results were satisfying. According to the measurement, the new modified electrode is a good alternative as chemical sensor for determination of other phenols.

Keywords: electrochemistry, electrode, limit of detection, sensor

Procedia PDF Downloads 145
1537 Characterization and Degradation of 3D Printed Polycaprolactone-Freeze Dried Bone Matrix Constructs for Use in Critical Sized Bone Defects

Authors: Samantha Meyr, Eman Mirdamadi, Martha Wang, Tao Lowe, Ryan Smith, Quinn Burke

Abstract:

Critical-sized bone defects (CSD) treatment options remain a major clinical orthopedic challenge. They are uniquely contoured diseased or damaged bones and can be defined as those that will not heal spontaneously and require surgical intervention. Autografts are the current gold standard CSD treatment, which are histocompatible and provoke a minimal immunogenic response; however, they can cause donor site morbidity and will not suffice for the size required for replacement. As an alternative to traditional surgical methods, bone tissue engineering will be implemented via 3D printing methods. A freeze-dried bone matrix (FDBM) is a type of graft material available but will only function as desired when in the presence of bone growth factors. Polycaprolactone (PCL) is a known biodegradable material with good biocompatibility that has been proven manageable in 3D printing as a medical device. A 3D-extrusion printing strategy is introduced to print these materials into scaffolds for bone grafting purposes, which could be more accessible and rapid than the current standard. Mechanical, thermal, cytotoxic, and physical properties were investigated throughout a degradation period of 6 months using fibroblasts and dental pulp stem cells. PCL-FDBM scaffolds were successfully printed with high print fidelity in their respective pore sizes and allograft content. Additionally, we have created a method for evaluating PCL using differential scanning calorimetry (DSC) and have evaluated PCL degradation over roughly 6 months.

Keywords: 3D printing, bone tissue engineering, cytotoxicity, degradation, scaffolds

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1536 Comparison between Some of Robust Regression Methods with OLS Method with Application

Authors: Sizar Abed Mohammed, Zahraa Ghazi Sadeeq

Abstract:

The use of the classic method, least squares (OLS) to estimate the linear regression parameters, when they are available assumptions, and capabilities that have good characteristics, such as impartiality, minimum variance, consistency, and so on. The development of alternative statistical techniques to estimate the parameters, when the data are contaminated with outliers. These are powerful methods (or resistance). In this paper, three of robust methods are studied, which are: Maximum likelihood type estimate M-estimator, Modified Maximum likelihood type estimate MM-estimator and Least Trimmed Squares LTS-estimator, and their results are compared with OLS method. These methods applied to real data taken from Duhok company for manufacturing furniture, the obtained results compared by using the criteria: Mean Squared Error (MSE), Mean Absolute Percentage Error (MAPE) and Mean Sum of Absolute Error (MSAE). Important conclusions that this study came up with are: a number of typical values detected by using four methods in the furniture line and very close to the data. This refers to the fact that close to the normal distribution of standard errors, but typical values in the doors line data, using OLS less than that detected by the powerful ways. This means that the standard errors of the distribution are far from normal departure. Another important conclusion is that the estimated values of the parameters by using the lifeline is very far from the estimated values using powerful methods for line doors, gave LTS- destined better results using standard MSE, and gave the M- estimator better results using standard MAPE. Moreover, we noticed that using standard MSAE, and MM- estimator is better. The programs S-plus (version 8.0, professional 2007), Minitab (version 13.2) and SPSS (version 17) are used to analyze the data.

Keywords: Robest, LTS, M estimate, MSE

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1535 A Parking Demand Forecasting Method for Making Parking Policy in the Center of Kabul City

Authors: Roien Qiam, Shoshi Mizokami

Abstract:

Parking demand in the Central Business District (CBD) has enlarged with the increase of the number of private vehicles due to rapid economic growth, lack of an efficient public transport and traffic management system. This has resulted in low mobility, poor accessibility, serious congestion, high rates of traffic accident fatalities and injuries and air pollution, mainly because people have to drive slowly around to find a vacant spot. With parking pricing and enforcement policy, considerable advancement could be found, and on-street parking spaces could be managed efficiently and effectively. To evaluate parking demand and making parking policy, it is required to understand the current parking condition and driver’s behavior, understand how drivers choose their parking type and location as well as their behavior toward finding a vacant parking spot under parking charges and search times. This study illustrates the result from an observational, revealed and stated preference surveys and experiment. Attained data shows that there is a gap between supply and demand in parking and it has maximized. For the modeling of the parking decision, a choice model was constructed based on discrete choice modeling theory and multinomial logit model estimated by using SP survey data; the model represents the choice of an alternative among different alternatives which are priced on-street, off-street, and illegal parking. Individuals choose a parking type based on their preference concerning parking charges, searching times, access times and waiting times. The parking assignment model was obtained directly from behavioral model and is used in parking simulation. The study concludes with an evaluation of parking policy.

Keywords: CBD, parking demand forecast, parking policy, parking choice model

Procedia PDF Downloads 194
1534 Study of Methods to Reduce Carbon Emissions in Structural Engineering

Authors: Richard Krijnen, Alan Wang

Abstract:

As the world is aiming to reach net zero around 2050, structural engineers must begin finding solutions to contribute to this global initiative. Approximately 40% of global energy-related emissions are due to buildings and construction, and a building’s structure accounts for 50% of its embodied carbon, which indicates that structural engineers are key contributors to finding solutions to reach carbon neutrality. However, this task presents a multifaceted challenge as structural engineers must navigate technical, safety and economic considerations while striving to reduce emissions. This study reviews several options and considerations to reduce carbon emissions that structural engineers can use in their future designs without compromising the structural integrity of their proposed design. Low-carbon structures should adhere to several guiding principles. Firstly, prioritize the selection of materials with low carbon footprints, such as recyclable or alternative materials. Optimization of design and engineering methods is crucial to minimize material usage. Encouraging the use of recyclable and renewable materials reduces dependency on natural resources. Energy efficiency is another key consideration involving the design of structures to minimize energy consumption across various systems. Choosing local materials and minimizing transportation distances help in reducing carbon emissions during transport. Innovation, such as pre-fabrication and modular design or low-carbon concrete, can further cut down carbon emissions during manufacturing and construction. Collaboration among stakeholders and sharing experiences and resources are essential for advancing the development and application of low-carbon structures. This paper identifies current available tools and solutions to reduce embodied carbon in structures, which can be used as part of daily structural engineering practice.

Keywords: efficient structural design, embodied carbon, low-carbon material, sustainable structural design

Procedia PDF Downloads 41
1533 Development and Evaluation of a Nutraceutical Herbal Summer Drink

Authors: Munish Garg, Vinni Ahuja

Abstract:

In the past few years, the high consumption of soft drinks has attracted negative attention world-wide due to its possible adverse effects, leading the health conscious people to find alternative nutraceutical or herbal health drinks. In the present study, a nutraceutical soft drink was developed utilizing some easily available and well known traditional herbs having nutritional potential. The key ingredients were selected as bael, amla, lemon juice, ashwagandha and poppy seeds based on their household routine use in the summer with proven refreshing, cooling and energetic feeling since ages. After several trials made, the final composition of nutraceutical summer soft drink was selected as most suitable combination based on the taste, physicochemical, microbial and organoleptic point of view. The physicochemical analysis of the prepared drink found to contain optimum level of titratable acidity, total soluble solids and pH which were in accordance of the commercial recommendations. There were no bacterial colonies found in the product therefore found within limits. During the nine point’s hedonic scale sensory evaluation, the drink was strongly liked for colour, taste, flavour and texture. The formulation was found to contain flavonoids (80mg/100ml), phenolics (103mg/100ml), vitamin C (250mg/100ml) and has antioxidant potential (75.52%) apart from providing several other essential vitamins, minerals and healthy components. The developed nutraceutical drink provides an economical and feasible option for the consumers with very good taste combined with potential health benefits. The present drink is potentially capable to replace the synthetic soft drinks available in the market.

Keywords: herbal drink, summer drink, nutraceuticals, soft drink

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1532 Combustion and Emissions Performance of Syngas Fuels Derived from Palm Kernel Shell and Polyethylene (PE) Waste via Catalytic Steam Gasification

Authors: Chaouki Ghenai

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Computational fluid dynamics analysis of the burning of syngas fuels derived from biomass and plastic solid waste mixture through gasification process is presented in this paper. The syngas fuel is burned in gas turbine can combustor. Gas turbine can combustor with swirl is designed to burn the fuel efficiently and reduce the emissions. The main objective is to test the impact of the alternative syngas fuel compositions and lower heating value on the combustion performance and emissions. The syngas fuel is produced by blending Palm Kernel Shell (PKS) with Polyethylene (PE) waste via catalytic steam gasification (fluidized bed reactor). High hydrogen content syngas fuel was obtained by mixing 30% PE waste with PKS. The syngas composition obtained through the gasification process is 76.2% H2, 8.53% CO, 4.39% CO2 and 10.90% CH4. The lower heating value of the syngas fuel is LHV = 15.98 MJ/m3. Three fuels were tested in this study natural gas (100%CH4), syngas fuel and pure hydrogen (100% H2). The power from the combustor was kept constant for all the fuels tested in this study. The effect of syngas fuel composition and lower heating value on the flame shape, gas temperature, mass of carbon dioxide (CO2) and nitrogen oxides (NOX) per unit of energy generation is presented in this paper. The results show an increase of the peak flame temperature and NO mass fractions for the syngas and hydrogen fuels compared to natural gas fuel combustion. Lower average CO2 emissions at the exit of the combustor are obtained for the syngas compared to the natural gas fuel.

Keywords: CFD, combustion, emissions, gas turbine combustor, gasification, solid waste, syngas, waste to energy

Procedia PDF Downloads 593
1531 Removal of Diesel by Soil Washing Technologies Using a Non-Ionic Surfactant

Authors: Carolina Guatemala, Josefina Barrera

Abstract:

A large number of soils highly polluted with recalcitrant hydrocarbons and the limitation of the current bioremediation methods continue being the drawback for an efficient recuperation of these under safe conditions. In this regard, soil washing by degradable surfactants is an alternative option knowing the capacity of surfactants to desorb oily organic compounds. The aim of this study was the establishment of the washing conditions of a soil polluted with diesel, using a nonionic surfactant. A soil polluted with diesel was used. This was collected near to a polluted railway station zone. The soil was dried at room temperature and sieved to a mesh size 10 for its physicochemical and biological characterization. Washing of the polluted soil was performed with surfactant solutions in a 1:5 ratio (5g of soil per 25 mL of the surfactant solution). This was carried out at 28±1 °C and 150 rpm for 72 hours. The factors tested were the Tween 80 surfactant concentration (1, 2, 5 and 10%) and the treatment time. Residual diesel concentration was determined every 24 h. The soil was of a sandy loam texture with a low concentration of organic matter (3.68%) and conductivity (0.016 dS.m- 1). The soil had a pH of 7.63 which was slightly alkaline and a Total Petroleum Hydrocarbon content (TPH) of 11,600 ± 1058.38 mg/kg. The high TPH content could explain the low microbial count of 1.1105 determined as UFC per gram of dried soil. Within the range of the surfactant concentration tested for washing the polluted soil under study, TPH removal increased proportionally with the surfactant concentration. 5080.8 ± 422.2 ppm (43.8 ± 3.64 %) was the maximal concentration of TPH removed after 72 h of contact with surfactant pollution at 10%. Despite the high percentage of hydrocarbons removed, it is assumed that a higher concentration of these could be removed if the washing process is extended or is carried out by stages. Soil washing through the use of surfactants as a desorbing agent was found to be a viable and effective technology for the rapid recovery of soils highly polluted with recalcitrant hydrocarbons.

Keywords: diesel, hydrocarbons, soil washing, tween 80

Procedia PDF Downloads 142