Search results for: anechoic room
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1335

Search results for: anechoic room

585 The Moveable Cathode Water Cold Atmospheric Pressure Plasma Jet for Titanium Surface Treatment of Dental Implant

Authors: Nazanin Gerami, Shirin Adlparvar

Abstract:

In the present time in the laboratory, one can create an ionized gas, that is to say, plasma from room temperature up to ten times more than the temperature of the sun center (150,000,000). All these temperature spectrums of plasma have applications in different disciplines, including dentistry, medicine, science, surface treatment, nuclear waste disinfection, nuclear fusion technology, etc. However, for the sick of simplicity, all these plasma temperature spectrums are classified as cold or low-pressure non-thermal plasma and warm or high-pressure equilibrium plasma. The cold plasma, as we are interested in this paper, exists at lower ion and neutral temperatures with respect to electron temperature, but in the equilibrium plasma, the temperatures of ion and electron are fairly equal. The cold plasma is a partially ionized gas comprising ions, electrons, ultraviolet photons and reactive neutrals such as radicals, excited and ground-state molecules. Cold atmospheric pressure plasmas are widely used in diverse fields of dental medicine, such as the titanium surface of dental implants, which helps in reducing contact angle and supporting the spread of osteoblastic cells and is known to aid in osteoblastic proliferation and osseointegration, thus increasing the success rates of implants. This article focuses on the anticipated uses of a newly designed water-cooled adjustable cathode cold atmospheric pressure plasma Jet (CAPPJ) for titanium surface treatment in dental implant placement.

Keywords: CAPPJ, surface modification, osseointegration, plasma medicine, dentistry

Procedia PDF Downloads 130
584 Monodisperse Hallow Sandwich MOF for the Catalytic Oxidation of Benzene at Room Temperature

Authors: Srinivasapriyan Vijayan

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Phenol is one of the most vital chemical in industry. Nowadays, phenol production is based upon the three-step cumene process, which involves a hazardous cumene hydroperoxide intermediate and produces nearly equimolar amounts of acetone as a coproduct. An attractive route in phenol production is the direct one-step selective hydroxylation of benzene using eco-friendly oxidants such as O2, N2O, and H2O2. In particular, the direct hydroxylation of benzene to form phenol with O2 has recently attracted extensive research attention because this process is green clean and eco-friendly. However, most of the catalytic systems involving O2 have a low rate of hydroxylation because the direct introduction of hydroxyl functionality into benzene is challenging. Almost all the developed catalytic systems require an elevated temperature and suffer from low conversion because of the notoriously low reactivity of aromatic C–H bonds. Moreover, increased reactivity of phenol relative to benzene makes the selective oxidation of benzene to phenol very difficult, especially under heating conditions. Hollow spheres, a very fascinating class of materials with good permeation and low density, highly monodisperse MOF hollow sandwich spheres have been rationally synthesized using monodisperse polystyrene (PS) nanoparticles as templates through a versatile step-by-step self-assembly strategy. So, our findings could pave the way toward highly efficient nonprecious catalysts for low-temperature oxidation reactions in heterogeneous catalysis. Because it is easy post-reaction separation, its cheap, green and recyclable.

Keywords: benzene hydroxylation, Fe-based metal organic frameworks, molecular oxygen, phenol

Procedia PDF Downloads 203
583 Binary Metal Oxide Catalysts for Low-Temperature Catalytic Oxidation of HCHO in Air

Authors: Hanjie Xie, Raphael Semiat, Ziyi Zhong

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It is well known that many oxidation reactions in nature are closely related to the origin and life activities. One of the features of these natural reactions is that they can proceed under mild conditions employing the oxidant of molecular oxygen (O₂) in the air and enzymes as catalysts. Catalysis is also a necessary part of life for human beings, as many chemical and pharmaceutical industrial processes need to use catalysts. However, most heterogeneous catalytic reactions must be run at high operational reaction temperatures and pressures. It is not strange that, in recent years, research interest has been redirected to green catalysis, e.g., trying to run catalytic reactions under relatively mild conditions as much as possible, which needs to employ green solvents, green oxidants such O₂, particularly air, and novel catalysts. This work reports the efficient binary Fe-Mn metal oxide catalysts for low-temperature formaldehyde (HCHO) oxidation, a toxic pollutant in the air, particularly in indoor environments. We prepared a series of nanosized FeMn oxide catalysts and found that when the molar ratio of Fe/Mn = 1:1, the catalyst exhibited the highest catalytic activity. At room temperature, we realized the complete oxidation of HCHO on this catalyst for 20 h with a high GHSV of 150 L g⁻¹ h⁻¹. After a systematic investigation of the catalyst structure and the reaction, we identified the reaction intermediates, including dioxymethylene, formate, carbonate, etc. It is found that the oxygen vacancies and the derived active oxygen species contributed to this high-low-temperature catalytic activity. These findings deepen the understanding of the catalysis of these binary Fe-Mn metal oxide catalysts.

Keywords: oxygen vacancy, catalytic oxidation, binary transition oxide, formaldehyde

Procedia PDF Downloads 123
582 Application of Molecular Materials in the Manufacture of Flexible and Organic Devices for Photovoltaic Applications

Authors: Mariana Gomez Gomez, Maria Elena Sanchez Vergara

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Many sustainable approaches to generate electric energy have emerged in the last few decades; one of them is through solar cells. Yet, this also has the disadvantage of highly polluting inorganic semiconductor manufacturing processes. Therefore, the use of molecular semiconductors must be considered. In this work, allene compounds C24H26O4 and C24H26O5 were used as dopants to manufacture semiconductors films based on PbPc by high-vacuum evaporation technique. IR spectroscopy was carried out to determine the phase and any significant chemical changes which may occur during the thermal evaporation. According to UV-visible spectroscopy and Tauc’s model, the deposition process generated thin films with an activation energy range of 1.47 to 1.55 eV for direct transitions and 1.29 to 1.33 eV for indirect transitions. These values place the manufactured films within the range of low bandgap semiconductors. The flexible devices were manufactured: polyethylene terephthalate (PET), Indium tin oxide (ITO)/organic semiconductor/ Cubic Close Packed (CCP). The characterization of the devices was carried out by evaluating electrical conductivity using the four-probe collinear method. I-V curves were obtained under different lighting conditions at room temperature. OS1 (PbPc/C24H26O4) showed an Ohmic behavior, while OS2 (PbPc/C24H26O5) reached higher current values ​​at lower voltages. The results obtained show that the semiconductors devices doped with allene compounds can be used in the manufacture of optoelectronic devices.

Keywords: electrical properties, optical gap, phthalocyanine, thin film.

Procedia PDF Downloads 239
581 A Case Study of Physical and Psychological Forces in the Nigerian Criminal and Military Interrogations

Authors: Onimisi Ekuh Abdullahi, Lasbat Omoshalewa Akinsemoyin

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In Nigeria, over two decades now, there has been a steady increase in the insecurity of human lives and physical properties. In the South-South Nigeria, there is an acute insecurity of militants destroying oil pipe-lines and kidnapping cases; in the Middle-Belt zone, insecurity centers on kidnapping and in a few states crises between Herdsmen and Farmers range like wildfire; in the South-Western zone, kidnapping is vile, in the North-East zone the issue of Boko Haram has become World-wide concern, and in North-west zone, cattle rustlers and religious crisis are of great concern. At the initial stage, the Nigerian Police Force was called upon to quell the crisis. It soon became obvious that the dimension of the crisis was beyond police force. The Nigerian Armed Forces were called to maintain peace and order because the magnitude of the crisis was threatening the national unity and cohesion. The main objective of this paper, was to examine the investigative techniques of criminal by the military in Nigeria. Specifically to examine the physical and psychological force; the abusive techniques and tactics; and suggest modern psychological techniques of interrogating criminals accepted to Human Right Activists and the rule of law. The process is to create room behaviour and practices that carefully monitored the trust and reliability of admissions produced by Psychological manipulative process in Nigeria.

Keywords: military, Nigerian criminal, physical, psychological force

Procedia PDF Downloads 147
580 Ultrasonic Investigation as Tool for Study of Molecular Interaction of 2-Hydroxy Substituted Pyrimidine Derivative at Different Concentrations

Authors: Shradha S. Binani, P. S. Bodke, R. V. Joat

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Recent decades have witnessed an exponential growth in the field of acoustical parameters and ultrasound on solid, liquid and gases. Ultrasonic propagation parameters yield valuable information regarding the behavior of liquid systems because intra and intermolecular association, dipolar interaction, complex formation and related structural changes affecting the compressibility of the system which in turn produces variations in the ultrasonic velocity. The acoustic and thermo dynamical parameters obtained in ultrasonic study show that ion-solvation is accompanied by the destruction or enhancement of the solvent structure. In the present paper the ultrasonic velocity (v), density (ρ), viscosity(η) have been measured for the pharmacological important compound 2-hydroxy substituted phenyl pyrimidine derivative (2-hydroxy-4-(4’-methoxy phenyl)-6-(2’-hydroxy-4’-methyl-5’-chlorophenyl)pyrimidine) in ethanol as a solvent by using different concentration at constant room temperature. These experimental data have been used to estimate physical parameter like adiabatic compressibility, intermolecular free length, relaxation time, free volume, specific acoustic impedance, relative association, Wada’s constant, Rao’s constant etc. The above parameters provide information in understanding the structural and molecular interaction between solute-solvent in the drug solution with respect to change in concentration.

Keywords: acoustical parameters, ultrasonic velocity, density, viscosity, 2-hydroxy substituted phenyl pyrimidine derivative

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579 Preparation of Wool Fiber/Keratin/PVA Film and Study on Their Structure and Properties

Authors: Min Wu, Shuming Shen, Xuhong Yang, Rencheng Tang

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Every year, numerous organic wastes from fiber byproducts of the wool textile industry, poor quality raw wools not fit for spinning, horns, nails and feathers from butchery are disposed. These wastes are abundant in keratin which is a renewable material. Wool fiber/keratin/PVA composites with different proportions were prepared in this study, and the influence of the proportions on their structure and properties were studied, aiming to understand the potential application of keratin in the field of biomedicine, degradable wrapper, and cosmetics film, and provide a new way to reuse keratin wastes. The urea / sodium sulfide / sodium dodecyl sulfate (SDS) method was used to dissolve the wool. After filtration and dialysis, the wool keratin solution was achieved. Then the keratin solution and polyvinal (PVA) solution were blended in different proportions, and the wool fibers cut into a certain length were cast into the blended solution. Thereby, various wool fiber/keratin/PVA composite films with different proportions were formed through pouring the solution into a flat box and drying at room temperature. The surface morphology, molecular structure, and mechanical property of the composite films were studied. The results showed that, there are α-helix structure, β-sheet and random coil conformations in the pure keratin film, as well as in the wool fiber. Compared with wool fiber, the crystallinity of keratin decreased. PVA can obviously improve the mechanical property of the blended film. When the blended ratio of keratin and PVA is 20:80, the mechanical property of the blended film is greatly improved. The composite films with 8%-16% of wool fibers have better flexibility than those without wool fibers.

Keywords: composite film, keratin, mechanical property, morphological structure, PVA, wool fiber

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578 Self-Action of Pyroelectric Spatial Soliton in Undoped Lithium Niobate Samples with Pyroelectric Mechanism of Nonlinear Response

Authors: Anton S. Perin, Vladimir M. Shandarov

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Compensation for the nonlinear diffraction of narrow laser beams with wavelength of 532 and the formation of photonic waveguides and waveguide circuits due to the contribution of pyroelectric effect to the nonlinear response of lithium niobate crystal have been experimentally demonstrated. Complete compensation for the linear and nonlinear diffraction broadening of light beams is obtained upon uniform heating of an undoped sample from room temperature to 55 degrees Celsius. An analysis of the light-field distribution patterns and the corresponding intensity distribution profiles allowed us to estimate the spacing for the channel waveguides. The observed behavior of bright soliton beams may be caused by their coherent interaction, which manifests itself in repulsion for anti-phase light fields and in attraction for in-phase light fields. The experimental results of this study showed a fundamental possibility of forming optically complex waveguide structures in lithium niobate crystals with pyroelectric mechanism of nonlinear response. The topology of these structures is determined by the light field distribution on the input face of crystalline sample. The optical induction of channel waveguide elements by interacting spatial solitons makes it possible to design optical systems with a more complex topology and a possibility of their dynamic reconfiguration.

Keywords: self-action, soliton, lithium niobate, piroliton, photorefractive effect, pyroelectric effect

Procedia PDF Downloads 154
577 Enhancement of Seed Longevity in Japonica Rice Cultivars Using Weed Rice

Authors: Jun-Hyeon Cho, Ji-Yoon Lee, Young-Bo Sohn, Dong-Jin Shin, You-Chun Song, Dong-Soo Park, Min-Hee Nam, Young-Up Kwon

Abstract:

Seed germination is a main factor in japonica rice cultivation. For japonica strains unlike indica lines, fast loss of germination ability during storage leads to risk of seeding and deterioration in the quality. To resolve these problems, germplasms screening for longevity was conducted using six days of compulsory aging stress of high temperature (50℃) and humidity (~95% RH). ‘Dharial’, a weedy rice collected in Bangladesh, was chosen as a source of seed longevity for long term storage. The strong germination trait originated from ‘Dharial’ was incorporated into Korean elite japonica cultivars, ‘Ilmi’ and ‘Gopum’, through backcross method. The germination ratio was evaluated after two years of room temperature storage conditions. A high germination ratio of 80.5% in donor plant of ‘Dharial’ and 77.3% in an introgression line were observed based on the two years of storage while the recurrent japonica cultivars, ‘Ilmi’ and ‘Gopum’, were failed in germination. As a result, we investigated the changes of quality affected by germination ability during storage. A gentle slope of palatability which is one of the measurement items for indirect selection indicator of high eating quality in japonica varieties was studied in a high germination ratio introgression line during storage. The introgression line could be useful to increase longevity and quality of japonica rice seed if molecular breeding strategy such as QTLs analysis is combined.

Keywords: rice, longevity, germination, storage

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576 Breakthrough Highly-Effective Extraction of Perfluoroctanoic Acid Using Natural Deep Eutectic Solvents

Authors: Sana Eid, Ahmad S. Darwish, Tarek Lemaoui, Maguy Abi Jaoude, Fawzi Banat, Shadi W. Hasan, Inas M. AlNashef

Abstract:

Addressing the growing challenge of per- and polyfluoroalkyl substances (PFAS) pollution in water bodies, this study introduces natural deep eutectic solvents (NADESs) as a pioneering solution for the efficient extraction of perfluorooctanoic acid (PFOA), one of the most persistent and concerning PFAS pollutants. Among the tested NADESs, trioctylphosphine oxide: lauric acid (TOPO:LauA) in a 1:1 molar ratio was distinguished as the most effective, achieving an extraction efficiency of approximately 99.52% at a solvent-to-feed (S:F) ratio of 1:2, room temperature, and neutral pH. This efficiency is achieved within a notably short mixing time of only one min, which is significantly less than the time required by conventional methods, underscoring the potential of TOPO:LauA for rapid and effective PFAS remediation. TOPO:LauA maintained consistent performance across various operational parameters, including a range of initial PFOA concentrations (0.1 ppm to 1000 ppm), temperatures (15 °C to 100 °C), pH values (3 to 9), and S:F ratios (2:3 to 1:7), demonstrating its versatility and robustness. Furthermore, its effectiveness was consistently high over seven consecutive extraction cycles, highlighting TOPO:LauA as a sustainable, environmentally friendly alternative to hazardous organic solvents, with promising applications for reliable, repeatable use in combating persistent water pollutants such as PFOA.

Keywords: deep eutectic solvents, natural deep eutectic solvents, perfluorooctanoic acid, water remediation

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575 An Innovative High Energy Density Power Pack for Portable and Off-Grid Power Applications

Authors: Idit Avrahami, Alex Schechter, Lev Zakhvatkin

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This research focuses on developing a compact and light Hydrogen Generator (HG), coupled with fuel cells (FC) to provide a High-Energy-Density Power-Pack (HEDPP) solution, which is 10 times Li-Ion batteries. The HEDPP is designed for portable & off-grid power applications such as Drones, UAVs, stationary off-grid power sources, unmanned marine vehicles, and more. Hydrogen gas provided by this device is delivered in the safest way as a chemical powder at room temperature and ambient pressure is activated only when the power is on. Hydrogen generation is based on a stabilized chemical reaction of Sodium Borohydride (SBH) and water. The proposed solution enables a ‘No Storage’ Hydrogen-based Power Pack. Hydrogen is produced and consumed on-the-spot, during operation; therefore, there’s no need for high-pressure hydrogen tanks, which are large, heavy, and unsafe. In addition to its high energy density, ease of use, and safety, the presented power pack has a significant advantage of versatility and deployment in numerous applications and scales. This patented HG was demonstrated using several prototypes in our lab and was proved to be feasible and highly efficient for several applications. For example, in applications where water is available (such as marine vehicles, water and sewage infrastructure, and stationary applications), the Energy Density of the suggested power pack may reach 2700-3000 Wh/kg, which is again more than 10 times higher than conventional lithium-ion batteries. In other applications (e.g., UAV or small vehicles) the energy density may exceed 1000 Wh/kg.

Keywords: hydrogen energy, sodium borohydride, fixed-wing UAV, energy pack

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574 Optimization the Conditions of Electrophoretic Deposition Fabrication of Graphene-Based Electrode to Consider Applications in Electro-Optical Sensors

Authors: Sepehr Lajevardi Esfahani, Shohre Rouhani, Zahra Ranjbar

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Graphene has gained much attention owing to its unique optical and electrical properties. Charge carriers in graphene sheets (GS) carry out a linear dispersion relation near the Fermi energy and behave as massless Dirac fermions resulting in unusual attributes such as the quantum Hall effect and ambipolar electric field effect. It also exhibits nondispersive transport characteristics with an extremely high electron mobility (15000 cm2/(Vs)) at room temperature. Recently, several progresses have been achieved in the fabrication of single- or multilayer GS for functional device applications in the fields of optoelectronic such as field-effect transistors ultrasensitive sensors and organic photovoltaic cells. In addition to device applications, graphene also can serve as reinforcement to enhance mechanical, thermal, or electrical properties of composite materials. Electrophoretic deposition (EPD) is an attractive method for development of various coatings and films. It readily applied to any powdered solid that forms a stable suspension. The deposition parameters were controlled in various thicknesses. In this study, the graphene electrodeposition conditions were optimized. The results were obtained from SEM, Ohm resistance measuring technique and AFM characteristic tests. The minimum sheet resistance of electrodeposited reduced graphene oxide layers is achieved at conditions of 2 V in 10 s and it is annealed at 200 °C for 1 minute.

Keywords: electrophoretic deposition (EPD), graphene oxide (GO), electrical conductivity, electro-optical devices

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573 Synthesis, Structural and Vibrational Studies of a New Lacunar Apatite: LIPB2CA2(PO4)3

Authors: A. Chari, A. El Bouari, B. Orayech, A. Faik, J. M. Igartua

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The phosphate is a natural resource of great importance in Morocco. In order to exploit this wealth, synthesis and studies of new a material based phosphate, were carried out. The apatite structure present o lot of characteristics, One of the main characteristics is to allow large and various substitutions for both cations and anions. Beside their biological importance in hard tissue (bone and teeth), apatites have been extensively studied for their potential use as fluorescent lamp phosphors or laser host materials.The apatite have interesting possible application fields such as in medicine as materials of bone filling, coating of dental implants, agro chemicals as artificial fertilizers. The LiPb2Ca2(PO4)3 was synthesized by the solid-state method, its crystal structure was investigated by Rietveld analysis using XRPD data. This material crystallizes with a structure of lacunar apatite anion deficit. The LiPb2Ca2(PO4)3 is hexagonal apatite at room temperature, adopting the space group P63/m (ITA No. 176), Rietveld refinements showed that the site 4f is shared by three cations Ca, Pb and Li. While the 6h is occupied by the Pb and Li cations. The structure can be described as built up from the PO4 tetrahedra and the sixfold coordination cavities, which delimit hexagonal tunnels along the c-axis direction. These tunnels are linked by the cations occupying the 4 f sites. Raman and Infrared spectroscopy analyses were carried out. The observed frequencies were assigned and discussed on the basis of unit-cell group analysis and by comparison to other apatite-type materials.

Keywords: apatite, Lacunar, crystal structure, Rietveldmethod, LiPb2Ca2(PO4)3, Phase transition

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572 Determination of Metalaxyl Efficacy in Controlling Phytophthora palmivora Infection of Durian Using Bioassay

Authors: Supawadee Phetkhajone, Wisuwat Songnuan

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Metalaxyl is one of the most common and effective fungicides used to control Phytophthora palmivora infection in durian (Durio zibethinus L.). The efficacy of metalaxyl residue in durian under greenhouse condition was evaluated using bioassay. Durian seedlings were treated with 2 methods of application, spraying, and soil drenching of metalaxyl, at recommended concentration (1000 mg/L). Mock treated samples were treated with 0.1% Tween20 and water for spraying and soil drenching methods, respectively. The experiment was performed in triplicates. Leaves were detached from treated plants at 0, 1, 7, 15, 20, 30, and 60 days after application, inoculated with metalaxyl-resistant and metalaxyl-sensitive isolates of P. palmivora, and incubated in a high humidity chamber for 5 days at room temperature. Metalaxyl efficacy was determined by measuring the lesion size on metalaxyl treated and mock treated samples. The results showed that metalaxyl can control metalaxyl-sensitive isolate of P. palmivora for at least 30 days after application in both methods of application. The metalaxyl-resistant isolate was not inhibited in all treatments. Leaf samples from spraying method showed larger lesions compared to soil drench method. These results demonstrated that metalaxyl applications, especially soil drenching methods showed high efficacy to control metalaxyl-sensitive isolates of P. palmivora, although it cannot control metalaxyl-resistant isolates of P. palmivora in all treatments. These qualitative data indicate that metalaxyl may suitable to control metalaxyl-sensitive isolates of P. palmivora infection.

Keywords: bioassay, degradation, durian, metalaxyl

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571 Design of RF Generator and Its Testing in Heating of Nickel Ferrite Nanoparticles

Authors: D. Suman, M. Venkateshwara Rao

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Cancer is a disease caused by an uncontrolled division of abnormal cells in a part of the body, which is affecting millions of people leading to death. Even though there have been tremendous developments taken place over the last few decades the effective therapy for cancer is still not a reality. The existing techniques of cancer therapy are chemotherapy and radio therapy which are having their limitations in terms of the side effects, patient discomfort, radiation hazards and the localization of treatment. This paper describes a novel method for cancer therapy by using RF-hyperthermia application of nanoparticles. We have synthesized ferromagnetic nanoparticles and characterized by using XRD and TEM. These nanoparticles after the biocompatibility studies will be injected in to the body with a suitable tracer element having affinity to the specific tumor site. When RF energy is applied to the nanoparticles at the tumor site it produces heat of excess room temperature and nearly 41-45°C is sufficient to kill the tumor cells. We have designed a RF source generator provided with a temperature feedback controller to control the radiation induced temperature of the tumor site. The temperature control is achieved through a negative feedback mechanism of the thermocouple and a relay connected to the power source of the RF generator. This method has advantages in terms of its effect like localized therapy, less radiation, and no side effects. It has several challenges in designing the RF source provided with coils suitable for the tumour site, biocompatibility of the nanomaterials, cooling system design for the RF coil. If we can overcome these challenges this method will be a huge benefit for the society.

Keywords: hyperthermia, cancer therapy, RF source generator, nanoparticles

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570 Investigation on Scattered Dose Rate and Exposure Parameters during Diagnostic Examination Done with an Overcouch X-Ray Tube in Nigerian Teaching Hospital

Authors: Gbenga Martins, Christopher J. Olowookere, Lateef Bamidele, Kehinde O. Olatunji

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The aims of this research are to measure the scattered dose rate during an X-ray examination in an X-ray room, compare the scattered dose rate with exposure parameters based on the body region examined, and examine the X-ray examination done with an over couch tube. The research was carried out using Gamma Scout software installation on the computer system (Laptop) to record the radiation counts, pulse rate, and dose rate. The measurement was employed by placing the detector at 900 to the incident X-ray. Proforma was used for the collection of patients’ data such as age, sex, examination type, and initial diagnosis. Data such as focus skin distance (FSD), body mass index (BMI), body thickness of the patients, the beam output (kVp) were collected at Obafemi Awolowo University, Ile-Ife, Western Nigeria. Total number of 136 patients was considered during this research. Dose rate range between 14.21 and 86.78 µSv/h for the plain abdominal region, 85.70 and 2.86 µSv/h for the lumbosacral region,1.3 µSv/yr and 3.6 µSv/yr in the pelvis region, 2.71 µSv/yr and 28.88 µSv/yr for leg region, 3.06 µSv/yr and 29.98 µSv/yr in hand region. The results of this study were compared with those of other studies carried out in other countries. The findings of this study indicated that the number of exposure parameters selected for each diagnostic examination contributed to the dose rate recorded. Therefore, these results call for a quality assurance program (QAP) in diagnostic X-ray units in Nigerian hospitals.

Keywords: X-radiation, exposure parameters, dose rate, pulse rate, number of counts, tube current, tube potential, diagnostic examination, scattered radiation

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569 Evaluating Mechanical Properties of CoNiCrAlY Coating from Miniature Specimen Testing at Elevated Temperature

Authors: W. Wen, G. Jackson, S. Maskill, D. G. McCartney, W. Sun

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CoNiCrAlY alloys have been widely used as bond coats for thermal barrier coating (TBC) systems because of low cost, improved control of composition, and the feasibility to tailor the coatings microstructures. Coatings are in general very thin structures, and therefore it is impossible to characterize the mechanical responses of the materials via conventional mechanical testing methods. Due to this reason, miniature specimen testing methods, such as the small punch test technique, have been developed. This paper presents some of the recent research in evaluating the mechanical properties of the CoNiCrAlY coatings at room and high temperatures, through the use of small punch testing and the developed miniature specimen tensile testing, applicable to a range of temperature, to investigate the elastic-plastic and creep behavior as well as ductile-brittle transition temperature (DBTT) behavior. An inverse procedure was developed to derive the mechanical properties from such tests for the coating materials. A two-layer specimen test method is also described. The key findings include: 1) the temperature-dependent coating properties can be accurately determined by the miniature tensile testing within a wide range of temperature; 2) consistent DBTTs can be identified by both the SPT and miniature tensile tests (~ 650 °C); and 3) the FE SPT modelling has shown good capability of simulating the early local cracking. In general, the temperature-dependent material behaviors of the CoNiCrAlY coating has been effectively characterized using miniature specimen testing and inverse method.

Keywords: NiCoCrAlY coatings, mechanical properties, DBTT, miniature specimen testing

Procedia PDF Downloads 151
568 Priming through Open Book MCQ Test: A Tool for Enhancing Learning in Medical Undergraduates

Authors: Bharti Bhandari, Bharati Mehta, Sabyasachi Sircar

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Medical education is advancing in India, with its advancement newer innovations are being incorporated in teaching and assessment methodology. Our study focusses on a teaching innovation that is more student-centric than teacher-centric and is the need of the day. The teaching innovation was carried out in 1st year MBBS students of our institute. Students were assigned control and test groups. Priming was done for the students in the test group with an open-book MCQ based test in a particular topic before delivering formal didactic lecture on that topic. The control group was not assigned any such exercise. This was followed by formal didactic lecture on the same topic. Thereafter, both groups were assessed on the same topic. The marks were compiled and analysed using appropriate statistical tests. Students were also given questionnaire to elicit their views on the benefits of “self-priming”. The mean marks scored in theory assessment by the test group were statistically higher than the marks scored by the controls. According to students’ feedback, the ‘self-priming “process was interesting, helped in better orientation during class-room lectures and better understanding of the topic. They want it to be repeated for other topics with moderate difficulty level. Better performance of the students in the primed group validates the combination of student-centric priming model and didactic lecture as superior to the conventional, teacher-centric methods alone. If this system is successfully followed, the present teacher-centric pedagogy should increasingly give way to student-centric activities where the teacher is only a facilitator.

Keywords: medical education, open-book test, pedagogy, priming

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567 Rapid and Efficient Removal of Lead from Water Using Chitosan/Magnetite Nanoparticles

Authors: Othman M. Hakami, Abdul Jabbar Al-Rajab

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Occurrence of heavy metals in water resources increased in the recent years albeit at low concentrations. Lead (PbII) is among the most important inorganic pollutants in ground and surface water. However, removal of this toxic metal efficiently from water is of public and scientific concern. In this study, we developed a rapid and efficient removal method of lead from water using chitosan/magnetite nanoparticles. A simple and effective process has been used to prepare chitosan/magnetite nanoparticles (NPs) (CS/Mag NPs) with effect on saturation magnetization value; the particles were strongly responsive to an external magnetic field making separation from solution possible in less than 2 minutes using a permanent magnet and the total Fe in solution was below the detection limit of ICP-OES (<0.19 mg L-1). The hydrodynamic particle size distribution increased from an average diameter of ~60 nm for Fe3O4 NPs to ~75 nm after chitosan coating. The feasibility of the prepared NPs for the adsorption and desorption of Pb(II) from water were evaluated using Chitosan/Magnetite NPs which showed a high removal efficiency for Pb(II) uptake, with 90% of Pb(II) removed during the first 5 minutes and equilibrium in less than 10 minutes. Maximum adsorption capacities for Pb(II) occurred at pH 6.0 and under room temperature were as high as 85.5 mg g-1, according to Langmuir isotherm model. Desorption of adsorbed Pb on CS/Mag NPs was evaluated using deionized water at different pH values ranged from 1 to 7 which was an effective eluent and did not result the destruction of NPs, then, they could subsequently be reused without any loss of their activity in further adsorption tests. Overall, our results showed the high efficiency of chitosan/magnetite nanoparticles (NPs) in lead removal from water in controlled conditions, and further studies should be realized in real field conditions.

Keywords: chitosan, magnetite, water, treatment

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566 Temperament as a Success Determinant in Formative Assessment

Authors: George Fomunyam Kehdinga

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Assessment is a vital part of the educational process, and formative assessment is a way of ensuring that higher education achieves the desired effects. Different factors influence how students perform in assessments in general, and formative assessment in particular and temperament is one of such determining factors. This paper which is a qualitative case study of four universities in four different countries examines how the temperamental make up of students either empowers them to perform excellently in formative assessment or incapacitates their performance. These four universities were chosen from Cameroon, South Africa, United Kingdom and the United States of America and three students were chosen from each institution, six of which were undergraduate student and six postgraduate students. Data in this paper was generated through qualitative interviews and document analyses which was preceded by a temperament test. From the data generated, it was discovered that cholerics who are natural leaders, hence do not struggle to express themselves often perform excellently in formative assessment while sanguines on the other hand who are also extroverts like cholerics perform relatively well. Phlegmatics and melancholics performed averagely and poorly respectively in formative assessment because they are naturally prone to fear and hate such activities because they like keeping to themselves. The paper, therefore, suggest that temperament is a success determinant in formative assessment. It also proposes that lecturers need and understanding of temperaments to be able to fully administer formative assessment in the lecturer room. It also suggests that assessment should be balance in the classroom so that some students because of their temperamental make-up are not naturally disadvantaged while others are performing excellently. Lastly, the paper suggests that since formative assessment is a process of generating data, it should be contextualised or given and individualised approach so as to ensure that trustworthy data is generated.

Keywords: temperament, formative assessment, academic success, students

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565 An Innovative Use of Flow Columns in Electrocoagulation Reactor to Control Water Temperature

Authors: Khalid S. Hashim, Andy Shaw, Rafid Alkhaddar, David Phipps, Ortoneda Pedrola

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Temperature is an essential parameter in the electrocoagulation process (EC) as it governs the solubility of electrodes and the precipitates and the collision rate of particles in water being treated. Although it has been about 100 years since the EC technology was invented and applied in water and wastewater treatment, the effects of temperature on the its performance were insufficiently investigated. Thus, the present project aims to fill this gap by an innovative use of perforated flow columns in the designing of a new EC reactor (ECR1). The new reactor (ECR1) consisted of a Perspex made cylinder container supplied with a flow column consisted of perorated discoid electrodes that made from aluminium. The flow column has been installed vertically, half submerged in the water being treated, inside a plastic cylinder. The unsubmerged part of the flow column works as a radiator for the water being treated. In order to investigate the performance of ECR1; water samples with different initial temperatures (15, 20, 25, 30, and 35 °C) to the ECR1 for 20 min. Temperature of effluent water samples were measured using Hanna meter (Model: HI 98130). The obtained results demonstrated that the ECR1 reduced water temperature from 35, 30, and 25 °C to 24.6, 23.8, and 21.8 °C respectively. While low water temperature, 15 °C, increased slowly to reach 19.1 °C after 15 minutes and kept the same level till the end of the treatment period. At the same time, water sample with initial temperature of 20 °C showed almost a steady level of temperature along the treatment process, where the temperature increased negligibly from 20 to 20.1 °C after 20 minutes of treatment. In conclusion, ECR1 is able to control the temperature of water being treated around the room temperature even when the initial temperature was high (35 °C) or low (15 °C).

Keywords: electrocoagulation, flow column, treatment, water temperature

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564 Effect of Jatropha curcas Leaf Extract on Castor Oil Induced Diarrhea in Albino Rats

Authors: Fatima U. Maigari, Musa Halilu, M. Maryam Umar, Rabiu Zainab

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Plants as therapeutic agents are used as drug in many parts of the world. Medicinal plants are mostly used in developing countries due to culture acceptability, belief or due to lack of easy access to primary health care services. Jatropha curcas is a plant from the Euphorbiaceae family which is widely used in Northern Nigeria as an anti-diarrheal agent. This study was conducted to determine the anti-diarrheal effect of the leaf extract on castor oil induced diarrhea in albino rats. The leaves of J. curcas were collected from Balanga Local government in Gombe State, north-eastern Nigeria; due to its bioavailability. The leaves were air-dried at room temperature and ground to powder. Phytochemical screening was done and different concentrations of the extract was prepared and administered to the different categories of experimental animals. From the results, aqueous leaf extract of Jatropha curcas at doses of 200mg/Kg and 400mg/Kg was found to reduce the mean stool score as compared to control rats, however, maximum reduction was achieved with the standard drug of Loperamide (5mg/Kg). Treatment of diarrhea with 200mg/Kg of the extract did not produce any significant decrease in stool fluid content but was found to be significant in those rats that were treated with 400mg/Kg of the extract at 2hours (0.05±0.02) and 4hours (0.01±0.01). A significant reduction of diarrhea in the experimental animals signifies it to possess some anti-diarrheal activity.

Keywords: anti-diarrhea, diarrhea, Jatropha curcas, loperamide

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563 Measuring the Effect of Co-Composting Oil Sludge with Pig, Cow, Horse And Poultry Manures on the Degradation in Selected Polycyclic Aromatic Hydrocarbons Concentrations

Authors: Ubani Onyedikachi, Atagana Harrison Ifeanyichukwu, Thantsha Mapitsi Silvester

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Components of oil sludge (PAHs) are known cytotoxic, mutagenic and potentially carcinogenic compounds also bacteria and fungi have been found to degrade PAHs to innocuous compounds. This study is aimed at measuring the effect of pig, cow, horse and poultry manures on the degradation in selected PAHs present in oil sludge. Soil spiked with oil sludge was co-composted differently with each manure in a ratio of 2:1 (w/w) spiked soil: manure and wood-chips in a ratio of 2:1 (w/v) spiked soil: wood-chips. Control was set up similar as the one above but without manure. The mixtures were incubated for 10 months at room temperature. Compost piles were turned weekly and moisture level was maintained at between 50% and 70%. Moisture level, pH, temperature, CO2 evolution and oxygen consumption were measured monthly and the ash content at the end of experimentation. Highest temperature reached was 27.5 °C in all compost heaps, pH ranged from 5.5 to 7.8 and CO2 evolution was highest in poultry manure at 18.78μg/dwt/day. Microbial growth and activities were enhanced; bacteria identified were Bacillus, Arthrobacter and Staphylococcus species. Percentage reduction in PAHs was measured using automated soxhlet extractor with Dichloromethane coupled with gas chromatography/mass spectrometry (GC/MS). Results from PAH measurements showed reduction between 77% and 99%. Co-composting of spiked soils with animal manures enhanced the reduction in PAHs.

Keywords: animal manures, bioremediation, co-composting, oil refinery sludge, PAHs

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562 Impact of COVID-19 on Hospital Waste

Authors: Caroline Correia, Stefani Perna, John Gaughan, Elizabeth Cerceo

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Introduction: The COVID-19 pandemic has brought unprecedented changes to how hospitals function on a daily basis. Increased personal protective equipment (PPE) usage and measures to pre-package, separate, and decontaminate have the potential to increase the waste load. However, limiting non-essential surgeries drastically reduces operating room (OR) waste, and restricting visitation policies to contain outbreaks may help conserve resources. The impact of these policy changes with increased disposable PPE usage on hospital production of waste is unknown. Methods: Waste produced in pounds (lbs) was measured for January through June during both 2019 and 2020 through Stericycle in Cooper University Hospital in Camden, NJ. This timeframe was selected since the pandemic began in January 2020 in the US. The total waste produced during this time was 328,623 lbs in 2019 and 306,454 lbs in 2020. Using Poisson counts (α=.05), less waste was produced in 2020 (p < 0.001). The amount of sharps and regulated medical waste (grossly bloody items) were both significantly decreased as well (p < 0.0001, p=0.0002), and these account for 10-15% of the total waste produced. Discussion: Despite the increased usage of disposable PPE, overall hospital waste was decreased during the pandemic as compared to prior. As surgeries are estimated to be responsible for up to one-half of waste produced by hospitals, it is possible that constraint on elective procedures contributed to the decreased waste in all three categories; estimates of a 35% decrease in surgical volume would be expected to impact waste production. The effects of the pandemic on waste production should continue to be monitored to understand the environmental impact as health systems resume backlogged surgeries at a higher volume.

Keywords: COVID-19, hospital, surgery, waste

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561 A Comparative Analysis of the Factors Determining Improvement and Effectiveness of Mediation in Family Matters Regarding Child Protection in Australia and Poland

Authors: Beata Anna Bronowicka

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Purpose The purpose of this paper is to improve effectiveness of mediation in family matters regarding child protection in Australia and Poland. Design/methodology/approach the methodological approach is phenomenology. Two phenomenological methods of data collection were used in this research 1/ a doctrinal research 2/an interview. The doctrinal research forms the basis for obtaining information on mediation, the date of introduction of this alternative dispute resolution method to the Australian and Polish legal systems. No less important were the analysis of the legislation and legal doctrine in the field of mediation in family matters, especially child protection. In the second method, the data was collected by semi-structured interview. The collected data was translated from Polish to English and analysed using software program. Findings- The rights of children in the context of mediation in Australia and Poland differ from the recommendations of the UN Committee on the Rights of the Child, which require that children be included in all matters that concern them. It is the room for improvement in the mediation process by increasing child rights in mediation between parents in matters related to children. Children should have the right to express their opinion similarly to the case in the court process. The challenge with mediation is also better understanding the role of professionals in mediation as lawyers, mediators. Originality/value-The research is anticipated to be of particular benefit to parents, society as whole, and professionals working in mediation. These results may also be helpful during further legislative initiatives in this area.

Keywords: mediation, family law, children's rights, australian and polish family law

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560 Colonization of Embrionic Gonads of Nile Tilapia by Giant Gourami Testicular Germ Cells

Authors: Irma Andriani, Ita Djuwita, Komar Sumantadinata, Alimuddin

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The recent study has been conducted to develop testicular germ cell transplantation as a tool for preservation and propagation of male germ-plasm from endangered fish species, as well as to produce surrogate broodstock of commercially valuable fish. Giant gourami testis had been used as a model for donor and Nile tilapia larvae as recipient. We developed testicular cell xenotransplantation by optimizing the timing of intraperitoneal cell transplantation to recipient larvae aged 1, 3, 5 and 7 days post hatching (dph). Freshly isolated testis of giant gourami weighing 600–800 g were minced in dissociation medium and then incubated for 3 hours in room temperature to collect monodisperce cell suspension. Donor cells labeled with PKH 26 were transplanted into the peritoneal cavity of Nile tilapia larvae using glass micropipettes. Parameters observed were survival rate of Nile tilapia larvae at 24 hours post transplantation (pt) and colonization efficiency of donor cells at 2 and 3 months pt. The incorporated donor cells were observed under fluorescent microscope. The result showed that the lowest survival rate at 24 hours pt was 1 dph larvae (82.74±6.76%) and the highest survival rate were 3 and 5 dph larvae (95.00±5.00% and 95.00±2.50%, respectively). The highest colonization efficiency was on 3 dph larvae (61.1±34.71%) and the lowest colonization efficiency was on 7 dph larvae (19.43±17.33%). In conclusion, 3 dph Nile tilapia larvae was the best recipient for giant gourami testicular germ cells xenotransplantation.

Keywords: xenotransplantation, testicular germ cell, giant gourami, Nile tilapia, colonization efficiency

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559 A Study on Architectural Characteristics‎ of Traditional Iranian Ordinary Houses in Mashhad, Iran

Authors: Rana Daneshvar Salehi

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In many Iranian cities including ‎‎Mashhad‎, the capital of ‎‎‎‎Razavi Khorasan Province‎, ‎ordinary samples of domestic architecture ‎on a ‎small scale is not ‎‎‎considered as ‎heritage. ‎While the ‎principals of house formation are ‎‎respected in all ‎‎traditional Iranian ‎‎‎‎houses‎; ‎from moderate to great ones. During the past decade, Mashhad has lost its identity, and has become a modern city. Identifying it as the capital of the Islamic Culture in 2017 by ISESCO and consequently looking for new developments and transfiguration caused to demolish a large ‎number ‎of ‎traditional modest habitation. ‎For this ‎reason, the present paper aims to introduce ‎the three ‎undiscovered houses with the ‎historical and monumental values located in the ‎oldest ‎neighborhoods of Mashhad which have been neglected in the cultural ‎heritage field. The preliminary phase of this approach will be a measured survey to identify the significant characteristics ‎of ‎selected dwellings and understand the challenges through focusing on building ‎form, orientation, ‎‎room function, space proportion and ornamental elements’ details. A comparison between the ‎‎case studies and the wealthy domestically buildings ‎presents that a house belongs to inhabitants ‎with an average income could introduce the same accurate, regular, harmonic and proportionate ‎design which can be found in the great mansions. It reveals that an ordinary traditional house can ‎be regarded as valuable construction not only for its historical characteristics but also ‎for its ‎aesthetical and architectural features that could avoid further destructions in the future.

Keywords: traditional ordinary house, architectural characteristic, proportion, heritage

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558 An Application of Hip Arthroscopy after Acute Injury - A Case Report

Authors: Le Nguyen Binh, Luong Xuan Binh, Le Van Tuan, Tran Binh Duong, Truong Nguyen Khanh Hung, Do Le Hoang Son, Pham Quang Vinh, Hoang Quoc Huy, Nguyen Bach, Nguyen Quoc Khanh Le, Jiunn Horng Kang

Abstract:

Introduction: Traumatic hip dislocation is an emergency in young adult which can cause avascular necrosis of femoral head or osteoarthritis of hip joint. The reasons for these may be the loose body of bony or chondral fragments, which are difficult to be detected on CT scan or MRI. In those cases, Hip arthroscopy may be the method of choice for diagnosis and treatment of loose bodies in hip joint after traumatic dislocation. Methods: A case report is performed. A 55-year-old male patient was under hip arthroscopy to retrieve the loose body in the right hip joint. Results: The patient’s hip was reduced under anesthesia in the opeation room. Xray and CT scan post-reduction showed that his right hip was wide and a small fragment of femoral head (< 5mm) locking inside the joint. A hip arthroscopy was done to take the fragment out. Post-operation, the patient went under rehabilition. After 6 months, he can walk with full-weight bearing; no further dislocaion was noted, and the Harris score was 84 points. Conclusions: Although acute traumatic injury of hip joint is usually treated with open surgeries, these methods have many drawbacks, such as soft tissue destruction, blood-loss,….Despite its technical requirement, hip arthroscopy is less invasive and effective treatment. Therefore, it may be an alternative treatment for a traumatic hip injury and can be applied frequently in the near future.

Keywords: hip dislocation, hip arthroscopy, hip osteoarthritis, acute hip trauma

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557 Enhancing the Pricing Expertise of an Online Distribution Channel

Authors: Luis N. Pereira, Marco P. Carrasco

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Dynamic pricing is a revenue management strategy in which hotel suppliers define, over time, flexible and different prices for their services for different potential customers, considering the profile of e-consumers and the demand and market supply. This means that the fundamentals of dynamic pricing are based on economic theory (price elasticity of demand) and market segmentation. This study aims to define a dynamic pricing strategy and a contextualized offer to the e-consumers profile in order to improve the number of reservations of an online distribution channel. Segmentation methods (hierarchical and non-hierarchical) were used to identify and validate an optimal number of market segments. A profile of the market segments was studied, considering the characteristics of the e-consumers and the probability of reservation a room. In addition, the price elasticity of demand was estimated for each segment using econometric models. Finally, predictive models were used to define rules for classifying new e-consumers into pre-defined segments. The empirical study illustrates how it is possible to improve the intelligence of an online distribution channel system through an optimal dynamic pricing strategy and a contextualized offer to the profile of each new e-consumer. A database of 11 million e-consumers of an online distribution channel was used in this study. The results suggest that an appropriate policy of market segmentation in using of online reservation systems is benefit for the service suppliers because it brings high probability of reservation and generates more profit than fixed pricing.

Keywords: dynamic pricing, e-consumers segmentation, online reservation systems, predictive analytics

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556 Corrosion Behvaior of CS1018 in Various CO2 Capture Solvents

Authors: Aida Rafat, Ramazan Kahraman, Mert Atilhan

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The aggressive corrosion behavior of conventional amine solvents is one of main barriers against large scale commerizaliation of amine absorption process for carbon capture application. Novel CO2 absorbents that exhibit minimal corrosivity against operation conditions are essential to lower corrosion damage and control and ensure more robustness in the capture plant. This work investigated corrosion behavior of carbon steel CS1018 in various CO2 absrobent solvents. The tested solvents included the classical amines MEA, DEA and MDEA, piperazine activated solvents MEA/PZ, MDEA/PZ and MEA/MDEA/PZ as well as mixtures of MEA and Room Temperature Ionic Liquids RTIL, namely MEA/[C4MIM][BF4] and MEA/[C4MIM][Otf]. Electrochemical polarization technique was used to determine the system corrosiveness in terms of corrosion rate and polarization behavior. The process parameters of interest were CO2 loading and solution temperature. Electrochemical resulted showed corrosivity order of classical amines at 40°C is MDEA> MEA > DEA wherase at 80°C corrosivity ranking changes to MEA > DEA > MDEA. Corrosivity rankings were mainly governed by CO2 absorption capacity at the test temperature. Corrosivity ranking for activated amines at 80°C was MEA/PZ > MDEA/PZ > MEA/MDEA/PZ. Piperazine addition seemed to have a dual advanatge in terms of enhancing CO2 absorption capacity as well as nullifying corrosion. For MEA/RTIL mixtures, the preliminary results showed that the partial repalcement of aqueous phase in MEA solution by the more stable nonvolatile RTIL solvents reduced corrosion rates considerably.

Keywords: corrosion, amines, CO2 capture, piperazine, ionic liquids

Procedia PDF Downloads 450