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1477 Effect of L/D Ratio on the Performance of a Four-Lobe Pressure Dam Bearing
Authors: G. Bhushan, S. S. Rattan, N. P. Mehta
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A four-lobe pressure dam bearing which is produced by cutting two pressure dams on the upper two lobes and two relief-tracks on the lower two lobes of an ordinary four-lobe bearing is found to be more stable than a conventional four-lobe bearing. In this paper a four-lobe pressure dam bearing supporting rigid and flexible rotors is analytically investigated to determine its performance when L/D ratio is varied in the range 0.75 to 1.5. The static and dynamic characteristics are studied at various L/D ratios. The results show that the stability of a four-lobe pressure dam bearing increases with decrease in L/D ratios both for rigid as well as flexible rotors.Keywords: Four-lobe pressure dam bearing, finite-elementmethod, L/D ratio.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26251476 Foil Bearing Stiffness Estimation with Pseudospectral Scheme
Authors: Balaji Sankar, Sadanand Kulkarni
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Compliant foil gas lubricated bearings are used for the support of light loads in the order of few kilograms at high speeds, in the order of 50,000 RPM. The stiffness of the foil bearings depends both on the stiffness of the compliant foil and on the lubricating gas film. The stiffness of the bearings plays a crucial role in the stable operation of the supported rotor over a range of speeds. This paper describes a numerical approach to estimate the stiffness of the bearings using pseudo spectral scheme. Methodology to obtain the stiffness of the foil bearing as a function of weight of the shaft is given and the results are presented.Keywords: Foil bearing, simulation, numerical, stiffness estimation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12281475 Modeling of CO2 Removal from Gas Mixtureby 2-amino-2-methyl-1-propanol (AMP) Using the Modified Kent Eisenberg Model
Authors: H. Pahlavanzadeh, A.R.Jahangiri, I. Noshadi
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In this paper, the solubility of CO2 in AMP solution have been measured at temperature range of ( 293, 303 ,313,323) K.The amine concentration ranges studied are (2.0, 2.8, and 3.4) M. A solubility apparatus was used to measure the solubility of CO2 in AMP solution on samples of flue gases from Thermal and Central Power Plants of Esfahan Steel Company. The modified Kent Eisenberg model was used to correlate and predict the vapor-liquid equilibria of the (CO2 + AMP + H2O) system. The model predicted results are in good agreement with the experimental vapor-liquid equilibrium measurements.Keywords: AMP, Carbon dioxide; loading, Flue gases, Modified Kent Eisenberg model
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24641474 X-ray Pulse Profiles of PSR J0538+2817
Authors: Kun Tao Zhao, Na Wang, Jian Ping Yuan
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This paper reports our analysis of 163 ks observations of PSR J0538+2817 with the Rossi X-Ray Timing Explorer (RXTE).The pulse profiles, detected up to 60 keV, show a single peak asin the case for radio frequency. The profile is well described by one Gaussians function with full width at half maximum (FWHM) 0.04794. We compared the difference of arrival time between radio and X-ray pulse profiles for the first time. It turns out that the phase of radio emits precede the X-ray by 8.7 ± 4.5 ms. Furthermore we obtained the pulse profiles in the energy ranges of 2.29-6.18 keV, 6.18-12.63 keV and 12.63-17.36 keV. The intensity of pulses decreases with the increasing energy range. We discuss the emission geometry in our work.Keywords: RXTE, X-ray pulsars, PSR J0538+2817.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16141473 Numerical Study of Flow around Flat Tube between Parallel Walls
Authors: Hamidreza Bayat, Arash Mirabdolah Lavasani, Meysam Bolhasani, Sajad Moosavi
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Flow around a flat tube is studied numerically. Reynolds number is defined base on equivalent circular tube and it is varied in range of 100 to 300. Equations are solved by using finite volume method and results are presented in form of drag and lift coefficient. Results show that drag coefficient of flat tube is up to 66% lower than circular tube with equivalent diameter. In addition, by increasing l/D from 1 to 2, the drag coefficient of flat tube is decreased about 14-27%.
Keywords: Laminar flow, flat-tube, drag coefficient, cross-flow, heat exchanger.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20231472 Chemical Analysis of PM2.5 during Dry Deforestation Season in Southeast Asia
Authors: Bahareh Khezri, Richard D. Webster
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In Southeast Asia, during the dry season (August to October) forest fires in Indonesia emit pollutants into the atmosphere. For two years during this period, a total of 67 samples of 2.5 μm particulate matters were collected and analyzed for total mass and elemental composition with ICP - MS after microwave digestion. A study of 60 elements measured during these periods suggest that the concentration of most of elements, even those usually related to crustal source, are extremely high and unpredictable during the haze period. In By contrast, trace element concentration in non - haze months is more stable and covers a lower range. Other unexpected events and their effects on the findings are discussed.Keywords: Haze, ICP - MS, Particulate Patter, Transboundary Air Pollution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17661471 Promoting a Strategic Plan in the University Environment
Authors: Frantisek Jezek, Jan Sedlacek
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This paper is concerned with the role strategic management plays in higher education and the methods it entails. Using the University of West Bohemia and the Czech Republic as examples, the paper describes the methods used in furthering strategic objectives within institutions and their different parts (faculties, institutes). The nature of the demands faced by the university dictates the need for a strategic framework which defines the basic objectives and parameters of tertiary education and research in a local, regional and national context. Sharing strategies with a wider range of actors (universities, cities, regions, the practical sphere) is key to laying the foundations for more efficient cooperation.Keywords: Strategy, strategic plan, university, university environment.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13291470 The Validity Range of LSDP Robust Controller by Exploiting the Gap Metric Theory
Authors: Ali Ameur Haj Salah, Tarek Garna, Hassani Messaoud
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This paper attempts to define the validity domain of LSDP (Loop Shaping Design Procedure) controller system, by determining the suitable uncertainty region, so that linear system be stable. Indeed the LSDP controller cannot provide stability for any perturbed system. For this, we will use the gap metric tool that is introduced into the control literature for studying robustness properties of feedback systems with uncertainty. A 2nd order electric linear system example is given to define the validity domain of LSDP controller and effectiveness gap metric.
Keywords: LSDP, Gap metric, Robust Control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14951469 Estimating Enzyme Kinetic Parameters from Apparent KMs and Vmaxs
Authors: Simon Brown, Noorzaid Muhamad, David C Simcock
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The kinetic properties of enzymes are often reported using the apparent KM and Vmax appropriate to the standard Michaelis-Menten enzyme. However, this model is inappropriate to enzymes that have more than one substrate or where the rate expression does not apply for other reasons. Consequently, it is desirable to have a means of estimating the appropriate kinetic parameters from the apparent values of KM and Vmax reported for each substrate. We provide a means of estimating the range within which the parameters should lie and apply the method to data for glutamate dehydrogenase from the nematode parasite of sheep Teladorsagia circumcincta.Keywords: enzyme kinetics, glutamate dehydrogenase, intervalanalysis, parameter estimation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19421468 Classifying and Predicting Efficiencies Using Interval DEA Grid Setting
Authors: Yiannis G. Smirlis
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The classification and the prediction of efficiencies in Data Envelopment Analysis (DEA) is an important issue, especially in large scale problems or when new units frequently enter the under-assessment set. In this paper, we contribute to the subject by proposing a grid structure based on interval segmentations of the range of values for the inputs and outputs. Such intervals combined, define hyper-rectangles that partition the space of the problem. This structure, exploited by Interval DEA models and a dominance relation, acts as a DEA pre-processor, enabling the classification and prediction of efficiency scores, without applying any DEA models.Keywords: Data envelopment analysis, interval DEA, efficiency classification, efficiency prediction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9281467 Solvatochromic Shift and Estimation of Dipole Moment of Quinine Sulphate Dication
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Absorption and fluorescence spectra of quinine sulphate (QSD) have been recorded at room temperature in wide range of solvents of different polarities. The ground-state dipole moment of QSD was obtained from quantum mechanical calculations and the excited state dipole moment of QSD was estimated from Bakhshiev-s and Kawski-Chamma-Viallet-s equations by means of solvatochromic shift method. Higher value of dipole moment is observed for excited state as compared to the corresponding ground state value and this is attributed to the more polar excited state of QSD.Keywords: Dipole moment, Quinine sulphate dication, Solvatochromic shift
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23631466 Thermodynamic Study for Aggregation Behavior of Hydrotropic Solution
Authors: Meghal Desai, Jigisha Parikh
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Aggregation behavior of sodium salicylate and sodium cumene sulfonate was studied in aqueous solution at different temperature. Specific conductivity and relative viscosity were measured at different temperature to find minimum hydrotropic concentration. The thermodynamic parameters (free energy, enthalpy and entropy) were evaluated in the temperature range of 30°C-70°C. The free energy decreased with increase in temperature. The aggregation was found to be exothermic in nature and favored by positive value of entropy.
Keywords: Hydrotropes, Enthalpy, Entropy, Free Energy, Minimum Hydrotropic Concentration.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19901465 On Constructing Approximate Convex Hull
Authors: M. Zahid Hossain, M. Ashraful Amin
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The algorithms of convex hull have been extensively studied in literature, principally because of their wide range of applications in different areas. This article presents an efficient algorithm to construct approximate convex hull from a set of n points in the plane in O(n + k) time, where k is the approximation error control parameter. The proposed algorithm is suitable for applications preferred to reduce the computation time in exchange of accuracy level such as animation and interaction in computer graphics where rapid and real-time graphics rendering is indispensable.
Keywords: Convex hull, Approximation algorithm, Computational geometry, Linear time.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22911464 Preparation and Characterization of Self Assembled Gold Nanoparticles on Amino Functionalized SiO2 Dielectric Core
Authors: M.E.khosroshahi , M.S.Nourbakhsh
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Wet chemistry methods are used to prepare the SiO2/Au nanoshells. The purpose of this research was to synthesize gold coated SiO2 nanoshells for biomedical applications. Tunable nanoshells were prepared by using different colloidal concentrations. The nanoshells are characterized by FTIR, XRD, UV-Vis spectroscopy and atomic force microscopy (AFM). The FTIR results confirmed the functionalization of the surfaces of silica nanoparticles with NH2 terminal groups. A tunable absorption was observed between 470-600 nm with a maximum range of 530-560 nm. Based on the XRD results three main peaks of Au (111), (200) and (220) were identified. Also AFM results showed that the silica core diameter was about 100 nm and the thickness of gold shell about 10 nm.Keywords: Gold nanoshells, Synthesis, UV-vis spectroscopy, XRD, AFM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32691463 Magnetohydrodynamic Mixed Convective Flow in a Cavity
Authors: R.YadollahiFarsani, B. Ghasemi
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A magnetohydrodynamic mixed convective flow in a cavity was studied in this paper. The lower surface of cavity was heated from below whereas other walls of the cavity were thermally isolated. The governing two-dimensional flow equations have been solved by using finite volume code. The effects of magnetic field were studied on flow and temperature field and heat transfer performance at a wide range of parameters, Such as Hartmann (0≤Ha≤100) and Reynolds (1≤Re≤100) numbers. The results showed that as Hartman number increases the Nusselt number, representing heat transfer from the cavity decreases.Keywords: Cavity, Magnetic Field, Mixed Convection, Magnetohydrodynamic
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15721462 Study of Current Sheath Velocities in Tridimensional with Sahand Plasma Focus
Authors: M.A. Mohammadi, H.Alinejad, A.Piri
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The current sheath dynamics in plasma focus facilities is the most important factors. In this paper the current sheath velocity at three dimensional with Sahand plasma focus facility is investigated. For this purpose the discharge is produced in argon gas with deposited energy lying in the range of 20-37kJ. The current sheath is monitored using two tridimensional magnetic probes. These probes installed near the surface of the interior electrode (anode) at 125mm from the anode axis (pinch place). The effect of gas pressure on the current sheath velocity also is investigated.Keywords: Plasma focus, Current sheath, magnetic probe
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15341461 Association Rule and Decision Tree based Methodsfor Fuzzy Rule Base Generation
Authors: Ferenc Peter Pach, Janos Abonyi
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This paper focuses on the data-driven generation of fuzzy IF...THEN rules. The resulted fuzzy rule base can be applied to build a classifier, a model used for prediction, or it can be applied to form a decision support system. Among the wide range of possible approaches, the decision tree and the association rule based algorithms are overviewed, and two new approaches are presented based on the a priori fuzzy clustering based partitioning of the continuous input variables. An application study is also presented, where the developed methods are tested on the well known Wisconsin Breast Cancer classification problem. Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22781460 Design and Control of DC-DC Converter for the Military Application Fuel Cell
Authors: Tae-Yeong Lee, Eun-Ju Yoo, Won-Yeong Choi, Young-Woo Park
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This paper presents a 24 watts SEPIC converter design and control using microprocessor. SEPIC converter has advantages of a wide input range and miniaturization caused by the low stress at elements. There is also an advantage that the input and output are isolated in MOSFET-off state. This paper presents the PID control through the SEPIC converter transfer function using a DSP and the protective circuit for fuel cell from the over-current and inverse-voltage by using the characteristic of SEPIC converter. Then it derives them through the experiments.Keywords: DC-DC Converter, Fuel-Cell, Microprocessor Control, Military Converter, SEPIC Converter
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23161459 Removal of Basic Blue 3 from Aqueous Solution by Adsorption Onto Durio Ziberthinus
Authors: Siew-Teng
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Durian husk (DH), a fruit waste, was studied for its ability to remove Basic blue 3 (BB3) from aqueous solutions. Batch kinetic studies were carried out to study the sorption characteristics under various experimental conditions. The optimum pH for the dye removal occurred in the pH range of 3-10. Sorption was found to be concentration and agitation dependent. The kinetics of dye sorption fitted a pseudo-second order rate expression. Both Langmuir and Freundlich models appeared to provide reasonable fittings for the sorption data of BB3 on durian husk. Maximum sorption capacity calculated from the Langmuir model is 49.50 mg g-1.
Keywords: Durian husk, Batch study, Sorption, Basic Blue 3
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12651458 Characteristics of Turbulent Round Jets in its Potential-Core Region
Authors: S. Sivakumar, Ravikiran Sangras, Vasudevan Raghavan
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In this work, stationary hot-wire measurements are carried out to investigate the characteristics of a round free jet in its potential core region (0 ≤ x/d ≤ 10). Measurements are carried out on an incompressible round jet for a range of Reynolds numbers from 4000 to 8000, calculated based on the jet exit mean velocity and the nozzle diameter. The effect of flow velocity on the development characteristics of the jet in the core region is analyzed. Timeaveraged statistics, spectra of velocity and its higher order moments are presented and explained.Keywords: Contoured nozzle, hot-wire anemometer, Reynolds number, velocity fluctuations, velocity spectra.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 45761457 Detailed Phenomenological Study of 14N Elastically Scattered on 12C in a wide Energy Range
Authors: Sh. Hamada, N. Burtebayev, N. Amangeldi, A. Amar
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An experiment was performed with a 24.5 MeV 14N beam on a 12C target in the cyclotron DC-60 located in Astana, Kazakhstan, to study the elastic scattering of 14N on 12C; the scattering was also analyzed at different energies for tracking the phenomenon of remarkable structure at large angles. Its aims were to extend the measurements to very large angles, and attempt to uniquely identify the elastic scattering potential. Good agreement between the theoretical and experimental data has been obtained with suitable optical potential parameters. Optical model calculations with l -dependent imaginary potentials were also applied to the data and relatively good agreement was found.Keywords: Optical Potential Codes, Elastic Scattering, SPIVALCode.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15541456 Development of a Kinetic Model for the Photodegradation of 4-Chlorophenol using a XeBr Excilamp
Authors: M. Gomez, M. D. Murcia, E. Gomez, J. L. Gomez, N. Christofi
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Excilamps are new UV sources with great potential for application in wastewater treatment. In the present work, a XeBr excilamp emitting radiation at 283 nm has been used for the photodegradation of 4-chlorophenol within a range of concentrations from 50 to 500 mg L-1. Total removal of 4-chlorophenol was achieved for all concentrations assayed. The two main photoproduct intermediates formed along the photodegradation process, benzoquinone and hydroquinone, although not being completely removed, remain at very low residual concentrations. Such concentrations are insignificant compared to the 4-chlorophenol initial ones and non-toxic. In order to simulate the process and scaleup, a kinetic model has been developed and validated from the experimental data.Keywords: 4-chlorophenol, excilamps, kinetic model, photodegradation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13751455 Design of Auto Exposure Unit Based On 2-Way Histogram Equalization
Authors: Junghwan Choi, Seongsoo Lee
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Histogram equalization is often used in image enhancement, but it can be also used in auto exposure. However, conventional histogram equalization does not work well when many pixels are concentrated in a narrow luminance range.This paper proposes an auto exposure method based on 2-way histogram equalization. Two cumulative distribution functions are used, where one is from dark to bright and the other is from bright to dark. In this paper, the proposed auto exposure method is also designed and implemented for image signal processors with full-HD images.
Keywords: Histogram equalization, Auto exposure, Image signal processor, Low-cost, Full HD Video.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33821454 Measuring Pressure Wave Velocity in a Hydraulic System
Authors: Lari Kela, Pekka Vähäoja
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Pressure wave velocity in a hydraulic system was determined using piezo pressure sensors without removing fluid from the system. The measurements were carried out in a low pressure range (0.2 – 6 bar) and the results were compared with the results of other studies. This method is not as accurate as measurement with separate measurement equipment, but the fluid is in the actual machine the whole time and the effect of air is taken into consideration if air is present in the system. The amount of air is estimated by calculations and comparisons between other studies. This measurement equipment can also be installed in an existing machine and it can be programmed so that it measures in real time. Thus, it could be used e.g. to control dampers.Keywords: Bulk modulus, pressure wave, sound velocity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 42941453 Open Problems on Zeros of Analytic Functions in Finite Quantum Systems
Authors: Muna Tabuni
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The paper contains an investigation on basic problems about the zeros of analytic theta functions. A brief introduction to analytic representation of finite quantum systems is given. The zeros of this function and there evolution time are discussed. Two open problems are introduced. The first problem discusses the cases when the zeros follow the same path. As the basis change the quantum state |f transforms into different quantum state. The second problem is to define a map between two toruses where the domain and the range of this map are the analytic functions on toruses.
Keywords: open problems, constraint, change of basis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15371452 Limits of Phase Modulated Frequency Shifted Holographic Vibrometry at Low Amplitudes of Vibrations
Authors: Pavel Psota, Vít Lédl, Jan Václavík, Roman Doleček, Pavel Mokrý, Petr Vojtíšek
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This paper presents advanced time average digital holography by means of frequency shift and phase modulation. This technique can measure amplitudes of vibrations at ultimate dynamic range while the amplitude distribution evaluation is done independently in every pixel. The main focus of the paper is to gain insight into behavior of the method at low amplitudes of vibrations. In order to reach that, a set of experiments was performed. Results of the experiments together with novel noise suppression show the limit of the method to be below 0.1 nm.Keywords: Acousto-optical modulator, digital holography, low amplitudes, vibrometry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11111451 Combination of Electrodialysis and Electrodeionization for Treatment of Condensate from Ammonium Nitrate Production
Authors: Lubomir Machuca, Vit Fara
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Ammonium nitrate (AN) is produced by the reaction of ammonia and nitric acid, and a waste condensate is obtained. The condensate contains pure AN in concentration up to 10g/L. The salt content in the condensate is too high to discharge immediately into the river thus it must be treated. This study is concerned with the treatment of condensates from an industrial AN production by combination of electrodialysis (ED) and electrodeionization (EDI). The condensate concentration was in range 1.9–2.5g/L of AN. A pilot ED module with 25 membrane pairs following by a laboratory EDI module with 10 membrane pairs operated continuously during 800 hours. Results confirmed that the combination of ED and EDI is suitable for the condensate treatment.
Keywords: Desalination, electrodialysis, electrodeionization, fertilizer industry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31461450 An Interactive 3D Experience for the Creation of Personalized Styling
Authors: Dawei Lin
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This research proposes an Interactive 3D Experience to enhance customer value in the fantasy era. As products reach maturity, they become more similar in the range of functions that they provide. This leads to competition via reduced retail price and ultimately reduced profitability. A competitive design method is therefore needed that can produce higher value products. An Enhanced Value Experience has been identified that can assist designers to provide quality products and to give them a unique positioning. On the basis of this value opportunity, the method of Interactive 3D Experience has been formulated and applied to the domain of retail furniture. Through this, customers can create their own personalized styling via the interactive 3D platform.Keywords: Interactive 3D experience, enhanced valueexperience, value opportunity, personalized styling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12721449 Towards CO2 Adsorption Enhancement via Polyethyleneimine Impregnation
Authors: Supasinee Pipatsantipong, Pramoch Rangsunvigit, Santi Kulprathipanja
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To reduce the carbon dioxide emission into the atmosphere, adsorption is believed to be one of the most attractive methods for post-combustion treatment of flue gas. In this work, activated carbon (AC) was modified by polyethylenimine (PEI) via impregnation in order to enhance CO2 adsorption capacity. The adsorbents were produced at 0.04, 0.16, 0.22, 0.25, and 0.28 wt% PEI/AC. The adsorption was carried out at a temperature range from 30 °C to 75 °C and five different gas pressures up to 1 atm. TG-DTA, FT-IR, UV-visible spectrometer, and BET were used to characterize the adsorbents. Effects of PEI loading on the AC for the CO2 adsorption were investigated. Effectiveness of the adsorbents on the CO2 adsorption including CO2 adsorption capacity and adsorption temperature was also investigated. Adsorption capacities of CO2 were enhanced with the increase in the amount of PEI from 0.04 to 0.22 wt% PEI before the capacities decreased onwards from0.25 wt% PEI at 30 °C. The 0.22 wt% PEI/AC showed higher adsorption capacity than the AC for adsorption at 50 °C to 75 °C.Keywords: Activated Carbon, Adsorption, CO2, Polyethyleneimine
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21281448 Design an Electrical Nose with ZnO Nanowire Arrays
Authors: Amin Nekoubin, Abdolamir Nekoubin
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Vertical ZnO nanowire array films were synthesized based on aqueous method for sensing applications. ZnO nanowires were investigated structurally using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The gas-sensing properties of ZnO nanowires array films are studied. It is found that the ZnO nanowires array film sensor exhibits excellent sensing properties towards O2 and CO2 at 100 °C with the response time shorter than 5 s. High surface area / volume ratio of vertical ZnO nanowire and high mobility accounts for the fast response and recovery. The sensor response was measured in the range from 100 to 500 ppm O2 and CO2 in this study.Keywords: Gas sensor, semiconductor, ZnO, Nanowire array
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1543