Search results for: radiation treatment
1688 Risk Allocation in Public-Private Partnership (PPP) Projects for Wastewater Treatment Plants
Authors: Samuel Capintero, Ole H. Petersen
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This paper examines the utilization of public-private partnerships for the building and operation of wastewater treatment plants. Our research focuses on risk allocation in this kind of projects. Our analysis builds on more than hundred wastewater treatment plants built and operated through PPP projects in Aragon (Spain). The paper illustrates the consequences of an inadequate management of construction risk and an unsuitable transfer of demand risk in wastewater treatment plants. It also shows that the involvement of many public bodies at local, regional and national level further increases the complexity of this kind of projects and make time delays more likely.Keywords: Wastewater, treatment plants, PPP, construction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22701687 Submicron Laser-Induced Dot, Ripple and Wrinkle Structures and Their Applications
Authors: P. Slepicka, N. Slepickova Kasalkova, I. Michaljanicova, O. Nedela, Z. Kolska, V. Svorcik
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Polymers exposed to laser or plasma treatment or modified with different wet methods which enable the introduction of nanoparticles or biologically active species, such as amino-acids, may find many applications both as biocompatible or anti-bacterial materials or on the contrary, can be applied for a decrease in the number of cells on the treated surface which opens application in single cell units. For the experiments, two types of materials were chosen, a representative of non-biodegradable polymers, polyethersulphone (PES) and polyhydroxybutyrate (PHB) as biodegradable material. Exposure of solid substrate to laser well below the ablation threshold can lead to formation of various surface structures. The ripples have a period roughly comparable to the wavelength of the incident laser radiation, and their dimensions depend on many factors, such as chemical composition of the polymer substrate, laser wavelength and the angle of incidence. On the contrary, biopolymers may significantly change their surface roughness and thus influence cell compatibility. The focus was on the surface treatment of PES and PHB by pulse excimer KrF laser with wavelength of 248 nm. The changes of physicochemical properties, surface morphology, surface chemistry and ablation of exposed polymers were studied both for PES and PHB. Several analytical methods involving atomic force microscopy, gravimetry, scanning electron microscopy and others were used for the analysis of the treated surface. It was found that the combination of certain input parameters leads not only to the formation of optimal narrow pattern, but to the combination of a ripple and a wrinkle-like structure, which could be an optimal candidate for cell attachment. The interaction of different types of cells and their interactions with the laser exposed surface were studied. It was found that laser treatment contributes as a major factor for wettability/contact angle change. The combination of optimal laser energy and pulse number was used for the construction of a surface with an anti-cellular response. Due to the simple laser treatment, we were able to prepare a biopolymer surface with higher roughness and thus significantly influence the area of growth of different types of cells (U-2 OS cells).
Keywords: Polymer treatment, laser, periodic pattern, cell response.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7701686 Effects of Intrauterine and Extrauterine Exposure to 1800 MHz GSM-Like Radiofrequency Radiation on Liver Regulatory Enzymes Activities in Infant Female Rabbits
Authors: A. Tomruk, G. Guler, B. Tandogan, E. Ozgur, N.N. Ulusu, N. Seyhan
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In the present study, we aimed to design the intrauterine and extrauterine exposure to 1800 MHz GSM-like RF radiation and investigate its possible bio-effects on infant female rabbits. Totally thirty-six New Zealand White female rabbits, onemonth old, were randomly divided into four groups which are composed of 9 rabbits; i. Group I [Intrauterine (IU) exposure(-); Extrauterine (EU) exposure (-)], Group II [IU exposure (-); EU exposure (+)], Group III [IU exposure(+);EU exposure(-)], Group IV [IU exposure (+);EU exposure(+)]. The master regulatory enzymes activities of pentose phosphate pathway (glucose-6-phosphate dehydrogenase, G-6PD; 6-phosphogluconate dehydrogenase, 6- PGDH) and glutathione-dependent metabolism (glutathione peroxidase, GSH-Px; glutathione reductase, GR; glutathione Stransferase, GST, thioredoxin reductase, TRx) were analyzed in liver tissues of young female rabbits. Decreased G-6PD, 6-PGD, GSH-Px, GR activities were found in Group III compared to Group I (p<0.05, Mann Whitney). Increased GSH-px and TRx activities were found in Group IV compared to Group I (p<0.05, Mann Whitney). It can be concluded that the intrauterine and extrauterine exposure to GSMlike RF radiation may influence the liver regulatory enzymes activities.Keywords: Radiofrequency (RF), intrauterine (IU) andextrauterine (EU) exposure, infant female rabbits.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23041685 Grooved Linear Microstrip Patch Antenna Array
Authors: Ayesha Aslam, F A Bhatti
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A simple impedance matching technique for inset feed grooved microstrip patch antenna based on the concept of coplanar waveguide feed line has been developed and investigated for a printed antenna at X-Band frequency of 10GHz. The proposed technique has been used in the design of Linear Grooved Microstrip patch antenna array. The characteristics of the antenna are determined in terms of Return loss, VSWR, gain, radiation pattern etc. The measured and simulated results presented are found to be in good agreement.Keywords: Gain, Microstrip patch, return loss, VSWR, Radiation pattern, CPW Feed, Inset feed.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27961684 Separation of Hazardous Brominated Plastics from Waste Plastics by Froth Flotation after Surface Modification with Mild Heat-Treatment
Authors: Nguyen Thi Thanh Truc, Chi-Hyeon Lee, Byeong-Kyu Lee, Srinivasa Reddy Mallampati
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This study evaluated to facilitate separation of ABS plastics from other waste plastics by froth flotation after surface hydrophilization of ABS with heat treatment. The mild heat treatment at 100oC for 60s could selectively increase the hydrophilicity of the ABS plastics surface (i.e., ABS contact angle decreased from 79o to 65.8o) among other plastics mixture. The SEM and XPS results of plastic samples sufficiently supported the increase in hydrophilic functional groups and decrease contact angle on ABS surface, after heat treatment. As a result of the froth flotation (at mixing speed 150 rpm and airflow rate 0.3 L/min) after heat treatment, about 85% of ABS was selectively separated from other heavy plastics with 100% of purity. The effect of optimum treatment condition and detailed mechanism onto separation efficiency in the froth floatation was also investigated. This research is successful in giving a simple, effective, and inexpensive method for ABS separation from waste plastics.Keywords: ABS, hydrophilic, heat treatment, froth flotation, contact angle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22961683 A Comparison Study of the Removal of Selected Pharmaceuticals in Waters by Chemical Oxidation Treatments
Authors: F. Javier Benitez, Juan Luis Acero, Francisco J. Real, Gloria Roldan, Francisco Casas
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The degradation of selected pharmaceuticals in some water matrices was studied by using several chemical treatments. The pharmaceuticals selected were the beta-blocker metoprolol, the nonsteroidal anti-inflammatory naproxen, the antibiotic amoxicillin, and the analgesic phenacetin; and their degradations were conducted by using UV radiation alone, ozone, Fenton-s reagent, Fenton-like system, photo-Fenton system, and combinations of UV radiation and ozone with H2O2, TiO2, Fe(II), and Fe(III). The water matrices, in addition to ultra-pure water, were a reservoir water, a groundwater, and two secondary effluents from two municipal WWTP. The results reveal that the presence of any second oxidant enhanced the oxidation rates, with the systems UV/TiO2 and O3/TiO2 providing the highest degradation rates. It is also observed in most of the investigated oxidation systems that the degradation rate followed the sequence: amoxicillin > naproxen > metoprolol > phenacetin. Lower rates were obtained with the pharmaceuticals dissolved in natural waters and secondary effluents due to the organic matter present which consume some amounts of the oxidant agents.Keywords: Pharmaceuticals, UV radiation, ozone, advancedoxidation processes, water matrices, degradation rates
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22251682 Neutralization of Alkaline Waste-Waters using a Blend of Microorganisms
Authors: Rita Kumar, Alka Sharma, Purnima Dhall, Niha M. Kulshreshtha, Anil Kumar
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The efficient operation of any biological treatment process requires pre-treatment of incompatible pollutants such as acids, bases, oil, toxic substances, etc. which hamper the treatment of other major components which are otherwise degradable. The pre-treatment of alkaline waste-waters, generated from various industries like textile, paper & pulp, potato-processing industries, etc., having a pH of 10 or higher, is essential. The pre-treatment, i.e., neutralization of such alkaline waste-waters can be achieved by chemical as well as biological means. However, the biological pretreatment offers better package over the chemical means by being safe and economical. The biological pre-treatment can be accomplished by using a blend of microorganisms able to withstand such harsh alkaline conditions. In the present study, for the proper pre-treatment of alkaline waste-waters, a package of alkalophilic bacteria is formulated to neutralise the alkaline pH of the industrial waste-waters. The developed microbial package is cost-effective as well as environmental friendly.Keywords: alkaline, alkalophilic bacteria, biological, pollutants, textile.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30861681 Survey Gamma Radiation Measurements in Commercially-used Natural Tiling Rocks in Iran
Authors: A.Abbasi, F.Mirekhtiary
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The gamma radiation in samples of a variety of natural tiling rocks (granites) produced and imported in Iran use in the building industry was measured, employing high-resolution Gamma-ray spectroscopy. The rock samples were pulverized, sealed in 0.5 liter plastic Marinelli beakers, and measured in the laboratory with an accumulating time between 50000 and 80000 second each. From the measured Gamma-ray spectra, activity concentrations were determined for 232Th (range from 6.5 to 172.2 Bq kg-1), 238U (from 7.5 to 178.1 Bq kg-1 ),226Ra( from 3.8 to 94.2 Bq kg-1 ) 40K (from 556.9 to 1539.2 Bq kg-1). From the 29 samples measured in this study, “Nehbndan ( Berjand )" appears to present the highest concentrations for 232Th,“Big Red Flower (China) "for 238U , “ Khoram dareh" for 226 Ra and “ Peranshahr" for 40K , respectively.Keywords: activity concentration, natural radioactivity, tilingrocks (granites)
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13941680 Experimental and Theoretical Investigation of Rough Rice Drying in Infrared-assisted Hot Air Dryer Using Artificial Neural Network
Authors: D. Zare, H. Naderi, A. A. Jafari
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Drying characteristics of rough rice (variety of lenjan) with an initial moisture content of 25% dry basis (db) was studied in a hot air dryer assisted by infrared heating. Three arrival air temperatures (30, 40 and 500C) and four infrared radiation intensities (0, 0.2 , 0.4 and 0.6 W/cm2) and three arrival air speeds (0.1, 0.15 and 0.2 m.s-1) were studied. Bending strength of brown rice kernel, percentage of cracked kernels and time of drying were measured and evaluated. The results showed that increasing the drying arrival air temperature and radiation intensity of infrared resulted decrease in drying time. High bending strength and low percentage of cracked kernel was obtained when paddy was dried by hot air assisted infrared dryer. Between this factors and their interactive effect were a significant difference (p<0.01). An intensity level of 0.2 W/cm2 was found to be optimum for radiation drying. Furthermore, in the present study, the application of Artificial Neural Network (ANN) for predicting the moisture content during drying (output parameter for ANN modeling) was investigated. Infrared Radiation intensity, drying air temperature, arrival air speed and drying time were considered as input parameters for the model. An ANN model with two hidden layers with 8 and 14 neurons were selected for studying the influence of transfer functions and training algorithms. The results revealed that a network with the Tansig (hyperbolic tangent sigmoid) transfer function and trainlm (Levenberg-Marquardt) back propagation algorithm made the most accurate predictions for the paddy drying system. Mean square error (MSE) was calculated and found that the random errors were within and acceptable range of ±5% with coefficient of determination (R2) of 99%.
Keywords: Rough rice, Infrared-hot air, Artificial Neural Network
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18171679 Laser Excited Nuclear γ -Source of High Spectral Brightness
Authors: A. Аndreev, Yu. Rozhdestvenskii, К. Platonov, R. Salomaa
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This paper considers various channels of gammaquantum generation via an ultra-short high-power laser pulse interaction with different targets.We analyse the possibilities to create a pulsed gamma-radiation source using laser triggering of some nuclear reactions and isomer targets. It is shown that sub-MeV monochromatic short pulse of gamma-radiation can be obtained with pulse energy of sub-mJ level from isomer target irradiated by intense laser pulse. For nuclear reaction channel in light- atom materials, it is shown that sub-PW laser pulse gives rise to formation about million gamma-photons of multi-MeV energy.Keywords: High power laser, short pulse, fast particles, isomertarget.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18161678 Study of Aero-thermal Effects with Heat Radiation in Optical Side Window
Authors: Chun-Chi Li, Da-Wei Huang, Yin-Chia Su, Liang-Chih Tasi
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In hypersonic environments, the aerothermal effect makes it difficult for the optical side windows of optical guided missiles to withstand high heat. This produces cracking or breaking, resulting in an inability to function. This study used computational fluid mechanics to investigate the external cooling jet conditions of optical side windows. The turbulent models k-ε and k-ω were simulated. To be in better accord with actual aerothermal environments, a thermal radiation model was added to examine suitable amounts of external coolants and the optical window problems of aero-thermodynamics. The simulation results indicate that when there are no external cooling jets, because airflow on the optical window and the tail groove produce vortices, the temperatures in these two locations reach a peak of approximately 1600 K. When the external cooling jets worked at 0.15 kg/s, the surface temperature of the optical windows dropped to approximately 280 K. When adding thermal radiation conditions, because heat flux dissipation was faster, the surface temperature of the optical windows fell from 280 K to approximately 260 K. The difference in influence of the different turbulence models k-ε and k-ω on optical window surface temperature was not significant.Keywords: aero-optical side window, aerothermal effect, cooling, hypersonic flow
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31031677 A Compact Wearable Slot Antenna for LTE and WLAN Applications
Authors: Haider K. Raad
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In this paper, a compact wide-band, ultra-thin and flexible slot antenna intended for wearable applications is presented. The presented antenna is designed to provide Wireless Local Area Network (WLAN) and Long Term Evolution (LTE) connectivity. The presented design exhibits a relatively wide bandwidth (1600-3500 MHz below -6 dB impedance bandwidth limit). The antenna is positioned on a 33 mm x 30 mm flexible substrate with a thickness of 50 µm. Antenna properties, such as the far-field radiation patterns, scattering parameter S11 are provided. The presented compact, thin and flexible design along with excellent radiation characteristics are deemed suitable for integration into flexible and wearable devices.Keywords: Wearable Electronics, Slot Antenna, LTE, WLAN.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11841676 Electromagnetic Source Direction of Arrival Estimation via Virtual Antenna Array
Authors: Meiling Yang, Shuguo Xie, Yilong Zhu
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Nowadays, due to diverse electric products and complex electromagnetic environment, the localization and troubleshooting of the electromagnetic radiation source is urgent and necessary especially on the condition of far field. However, based on the existing DOA positioning method, the system or devices are complex, bulky and expensive. To address this issue, this paper proposes a single antenna radiation source localization method. A single antenna moves to form a virtual antenna array combined with DOA and MUSIC algorithm to position accurately, meanwhile reducing the cost and simplify the equipment. As shown in the results of simulations and experiments, the virtual antenna array DOA estimation modeling is correct and its positioning is credible.
Keywords: Virtual antenna array, DOA, localization, far field.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9631675 Anisotropic Constitutive Model and its Application in Simulation of Thermal Shock Wave Propagation for Cylinder Shell Composite
Authors: Xia Huang, Wenhui Tang, Banghai Jiang, Xianwen Ran
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In this paper, a plane-strain orthotropic elasto-plastic dynamic constitutive model is established, and with this constitutive model, the thermal shock wave induced by intense pulsed X-ray radiation in cylinder shell composite is simulated by the finite element code, then the properties of thermal shock wave propagation are discussed. The results show that the thermal shock wave exhibit different shapes under the radiation of soft and hard X-ray, and while the composite is radiated along different principal axes, great differences exist in some aspects, such as attenuation of the peak stress value, spallation and so on.Keywords: anisotropic constitutive model, thermal shock wave, X-ray, cylinder shell composite.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17371674 Feasibility of Leukemia Cancer Treatment (K562) by Atmospheric Pressure Plasma Jet
Authors: Mashayekh Amir Shahriar, Akhlaghi Morteza, Rajaee Hajar, Khani Mohammad Reza, Shokri Babak
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A new and novel approach in medicine is the use of cold plasma for various applications such as sterilization blood coagulation and cancer cell treatment. In this paper a pin-to-hole plasma jet suitable for biological applications is investigated and characterized and the possibility and feasibility of cancer cell treatment is evaluated. The characterization includes power consumption via Lissajous method, thermal behavior of plasma using Infra-red camera as a novel method, Optical Emission Spectroscopy (OES) to determine the species that are generated. Treatment of leukemia cancer cells is also implemented and MTT assay is used to evaluate viability.
Keywords: Atmospheric Pressure Plasma Jet (APPJ), Plasma Medicine, Cancer cell treatment, leukemia.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22261673 Dual Band Microstrip Patch Antenna for IEEE802.11b Application
Authors: Biplab Bag
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In this paper, the design of a coaxial feed single layer rectangular microstrip patch antenna for IEEE802.11b application is presented. The proposed antenna is designed by using substrate FR4_epoxy having permittivity of about 4.4 and tangent loss of 0.013. The characteristics of the substrate are designed and to evaluate the performance of modeled antenna using HFSS v.11 EM simulator, from Ansoft. The proposed antenna dual resonant frequency has been achieved in the band of 1.57GHz-1.68GHz (with BW 30 MHz) and 2.25 GHz -2.55GHz (with BW 40MHz). The simulation results with frequency response, radiation pattern and return loss, VSWR, Input Impedance are presented with appropriate table and graph.
Keywords: Microstrip, Radiation Pattern, Return Loss, Tangent Loss, VSWR.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30371672 Influence of Chemical Treatment on Elastic Properties of the Band Cotton Crepe 100%
Authors: Bachir Chemani, Rachid Halfaoui, Madani Maalem
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The manufacturing technology of band cotton is very delicate and depends to choice of certain parameters such as torsion of warp yarn. The fabric elasticity is achieved without the use of any elastic material, chemical expansion, artificial or synthetic and it’s capable of creating pressures useful for therapeutic treatments. Before use, the band is subjected to treatments of specific preparation for obtaining certain elasticity, however, during its treatment, there are some regression parameters. The dependence of manufacturing parameters on the quality of the chemical treatment was confirmed. The aim of this work is to improve the properties of the fabric through the development of manufacturing technology appropriately. Finally for the treatment of the strip pancake 100% cotton, a treatment method is recommended.
Keywords: Elastic, cotton, processing, torsion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15871671 Self-Organization of Radiation Defects: Temporal Dissipative Structures
Authors: Pavlo Selyshchev
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A theoretical approach to radiation damage evolution is developed. Stable temporal behavior taking place in solids under irradiation are examined as phenomena of self-organization in nonequilibrium systems. Experimental effects of temporal self-organization in solids under irradiation are reviewed. Their essential common properties and features are highlighted and analyzed. Dynamical model to describe development of self-oscillation of density of point defects under stationary irradiation is proposed. The emphasis is the nonlinear couplings between rate of annealing and density of defects that determine the kind and parameters of an arising self-oscillation. The field of parameters (defect generation rate and environment temperature) at which self-oscillations develop is found. Bifurcation curve and self-oscillation period near it is obtained.Keywords: Irradiation, Point Defects, Solids, Temporal Selforganization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19631670 Performance Evaluation of Thermosiphon Based Solar Water Heater in India
Authors: Dnyandip K. Bhamare, Manish K Rathod, Jyotirmay Banerjee
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This paper aims to study performance of a thermosiphon solar water heating system with the help of the proposed analytical model. This proposed model predicts the temperature and mass flow rate in a thermosiphon solar water heating system depending on radiation intensity and ambient temperature. The performance of the thermosiphon solar water heating system is evaluated in the Indian context. For this, eight cities in India are selected considering radiation intensity and geographical positions. Predicted performance at various cities reveals the potential for thermosiphon solar water in India.
Keywords: Collector outlet temperature, India, solar water heater, thermosiphon.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15321669 Spectrum Analysis with Monte Cralo Simulation, BEAMnrc, for Low Energy X-RAY
Authors: Z. Salehi Dehyagani, A. L. Yusoff
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BEAMnrc was used to calculate the spectrum and HVL for X-ray Beam during low energy X-ray radiation using tube model: SRO 33/100 /ROT 350 Philips. The results of BEAMnrc simulation and measurements were compared to the IPEM report number 78 and SpekCalc software. Three energies 127, 103 and 84 Kv were used. In these simulation a tungsten anode with 1.2 mm for Be window were used as source. HVLs were calculated from BEAMnrc spectrum with air Kerma method for four different filters. For BEAMnrc one billion particles were used as original particles for all simulations. The results show that for 127 kV, there was maximum 5.2 % difference between BEAMnrc and Measurements and minimum was 0.7% .the maximum 9.1% difference between BEAMnrc and IPEM and minimum was 2.3% .The maximum difference was 3.2% between BEAMnrc and SpekCal and minimum was 2.8%. The result show BEAMnrc was able to satisfactory predict the quantities of Low energy Beam as well as high energy X-ray radiation.Keywords: BEAMnr , Monte Carlo , HVL
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30431668 Impact Behavior of Cryogenically Treated En 52 and 21-4N Valve Steels
Authors: M. Arockia Jaswin, D. Mohan Lal
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Cryogenic treatment is the process of cooling a material to extremely low temperatures to generate enhanced mechanical and physical properties. The purpose of this study is to examine the effect of cryogenic treatment on the impact behavior of En 52 and 21-4N valve steels. The valve steels are subjected to shallow (193 K) and deep cryogenic treatment (85 K), and the impact behavior is compared with the valve steel materials subjected to conventional heat treatment. The impact test is carried out in accordance with the ASTM E 23-02a standard. The results show an improvement of 23 % in the impact energy for the En 52 deep cryo-treated samples when compared to that of the conventionally heat treated samples. It is revealed that during cryogenic treatment fine platelets of martensite are formed from the retained austenite, and these platelets promote the precipitation of fine carbides by a diffusion mechanism during tempering.
Keywords: Cryogenic treatment, valve steel, Fractograph, carbides, impact strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 45091667 Gamma Irradiation Effects on the Magnetic Properties of Hard Ferrites
Authors: F. Abbas Pour Khotbehsara, B. Salehpour, A. Kianvash
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Many industrial materials like magnets need to be tested for the radiation environment expected at linear colliders (LC) where the accelerator and detectors will be subjected to large influences of beta, neutron and gamma’s over their life Gamma irradiation of the permanent sample magnets using a 60Co source was investigated up to an absorbed dose of 700Mrad shows a negligible effect on some magnetic properties of Nd-Fe-B. In this work it has been tried to investigate the change of some important properties of Barium hexa ferrite. Results showed little decreases of magnetic properties at doses rang of 0.5 to 2.5 Mrad. But at the gamma irradiation dose up to 10 Mrad it is showed a few increase of properties. Also study of gamma irradiation of Nd-Fe-B showed considerably increase of magnetic properties.Keywords: Gamma ray irradiation, Hard Ferrite, Magnetic coefficient, Radiation dose.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26511666 Study the Influence of Chemical Treatment on the Compositional Changes and Defect Structures of ZnS Thin Film
Authors: N. Dahbi, D-E. Arafah
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The effect of chemical treatment in CdCl2 on the compositional changes and defect structures of potentially useful ZnS solar cell thin films prepared by vacuum deposition method was studied using the complementary Rutherford backscattering (RBS) and Thermoluminesence (TL) techniques. A series of electron and hole traps are found in the various as deposited samples studied. After treatment, perturbation on the intensity is noted; mobile defect states and charge conversion and/or transfer between defect states are found.Keywords: chemical treatment, defect, glow curve, RBS, thinfilm, thermoluminescence, ZnS, vacuum deposition
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15851665 UV Resistibility of a Carbon Nanofiber Reinforced Polymer Composite
Authors: A. Evcin, N. Çiçek Bezir, R. Duman, N. Duman
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Nowadays, a great concern is placed on the harmfulness of ultraviolet radiation (UVR) which attacks human bodies. Nanocarbon materials, such as carbon nanotubes (CNTs), carbon nanofibers (CNFs) and graphene, have been considered promising alternatives to shielding materials because of their excellent electrical conductivities, very high surface areas and low densities. In the present work, carbon nanofibers have been synthesized from solutions of Polyacrylonitrile (PAN)/ N,N-dimethylformamide (DMF) by electrospinning method. The carbon nanofibers have been stabilized by oxidation at 250 °C for 2 h in air and carbonized at 750 °C for 1 h in H2/N2. We present the fabrication and characterization of transparent and ultraviolet (UV) shielding CNF/polymer composites. The content of CNF filler has been varied from 0.2% to 0.6 % by weight. UV Spectroscopy has been performed to study the effect of composition on the transmittance of polymer composites.
Keywords: Electrospinning, carbon nanofiber, characterization, composites, nanofiber, ultraviolet radiation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7951664 Using SNAP and RADTRAD to Establish the Analysis Model for Maanshan PWR Plant
Authors: J. R. Wang, H. C. Chen, C. Shih, S. W. Chen, J. H. Yang, Y. Chiang
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In this study, we focus on the establishment of the analysis model for Maanshan PWR nuclear power plant (NPP) by using RADTRAD and SNAP codes with the FSAR, manuals, and other data. In order to evaluate the cumulative dose at the Exclusion Area Boundary (EAB) and Low Population Zone (LPZ) outer boundary, Maanshan NPP RADTRAD/SNAP model was used to perform the analysis of the DBA LOCA case. The analysis results of RADTRAD were similar to FSAR data. These analysis results were lower than the failure criteria of 10 CFR 100.11 (a total radiation dose to the whole body, 250 mSv; a total radiation dose to the thyroid from iodine exposure, 3000 mSv).Keywords: RADionuclide, transport, removal, and dose estimation, RADTRAD, symbolic nuclear analysis package, SNAP, dose, PWR.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10121663 The Impact of Treatment of Latent Tuberculosis on the Incidence : The Case of Algeria
Authors: Schehrazad Selmane
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We present a deterministic model which describes the dynamics of tuberculosis in Algerian population where the vaccination program with BCG is in place since 1969 and where the WHO recommendations regarding the DOTS (directly-observed treatment, short course) strategy are in application. The impact of an intervention program, targeting recently infected people among all close contacts of active cases and their treatment to prevent endogenous reactivation, on the incidence of tuberculosis, is investigated. We showed that a widespread treatment of latently infected individuals for some years is recommended to shift from higher to lower equilibrium state and thereafter relaxation is recommended.
Keywords: Deterministic model, reproduction number, stability, tuberculosis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19901662 PAPR Reduction in OFDM Systems Using Orthogonal Eigenvector Matrix
Authors: Md. Mahmudul Hasan
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OFDM systems are known to have a high PAPR (Peak-to-Average Power Ratio) compared with single-carrier systems. In fact, the high PAPR is one of the most detrimental aspects in the OFDM system, as it can cause power degradation (Inband distortion) and spectral spreading (Out-of-band radiation). In this paper, from the foundation of the PAPR analysis an effective method of PAPR reduction has been proposed based on Orthogonal Eigenvector Matrix (OEM) transform. Extensive computer simulations show that a PAPR reduction of up to 4.4 dB can be obtained without introducing in-band distortion or out-of-band radiation in the system.
Keywords: Orthogonal frequency division multiplexing (OFDM), peak-to-average power ratio (PAPR), Orthogonal Eigenvector Matrix (OEM).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20121661 Solar Energy for Water Conditioning
Authors: J. Pawłat, H. Stryczewska
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Shortening of natural resources will impose greater limitations of electric energy consumption in various fields including water treatment technologies. Small water treatment installations supplied with electric energy from solar sources are perfect example of zero-emission technology. Possibility of solar energy application, as one of the alternative energy resources for decontamination processes is strongly dependent on geographical location. Various examples of solar driven water purification systems are given and design of solar-water treatment installation based on ozone for the geographical conditions in Poland are presented.Keywords: solar energy, water purification, ozone water treatment
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17761660 Heat Treatment and Rest-Inserted Exercise Enhances EMG Activity of the Lower Limb
Authors: Jae Kyun Bang, Sung Jae Hwang, Chang Yong Ko, Chi Hyun Kim
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Prolonged immobilization leads to significant weakness and atrophy of the skeletal muscle and can also impair the recovery of muscle strength following injury. Therefore, it is important to minimize the period under immobilization and accelerate the return to normal activity. This study examined the effects of heat treatment and rest-inserted exercise on the muscle activity of the lower limb during knee flexion/extension. Twelve healthy subjects were assigned to 4 groups that included: (1) heat treatment + rest-inserted exercise; (2) heat + continuous exercise; (3) no heat + rest-inserted exercise; and (4) no heat + continuous exercise. Heat treatment was applied for 15 mins prior to exercise. Continuous exercise groups performed knee flexion/extension at 0.5 Hz for 300 cycles without rest whereas rest-inserted exercise groups performed the same exercise but with 2 mins rest inserted every 60 cycles of continuous exercise. Changes in the rectus femoris and hamstring muscle activities were assessed at 0, 1, and 2 weeks of treatment by measuring the electromyography signals of isokinetic maximum voluntary contraction. Significant increases in both the rectus femoris and hamstring muscles were observed after 2 weeks of treatment only when both heat treatment and rest-inserted exercise were performed. These results suggest that combination of various treatment techniques, such as heat treatment and rest-inserted exercise, may expedite the recovery of muscle strength following immobilization.Keywords: Electromyography, Heat Treatment, Muscle, Rest-Inserted Exercise.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18641659 Nitrogen Removal in a High-efficiency Denitrification/Oxic Filter treatment System for Advanced Treatment of Municipal Wastewater
Authors: D. W. Kim , D. J. Ryu, M. J. Go, D. Chang, S. B. Han, J. M. Hur, B. R. Chung, B. K. Kim, Yeon Hye Jin
Abstract:
Biological treatment of secondary effluent wastewater by two combined denitrification/oxic filtration systems packed with Lock type(denitrification filter) and ceramic ball (oxic filter) has been studied for 5months. Two phases of operating conditions were carried out with an influent nitrate and ammonia concentrations varied from 5.8 to 11.7mg/L and 5.4 to 12.4mg/L,respectively. Denitrification/oxic filter treatment system were operated under an EBCT (Empty Bed Contact Time) of 4h at system recirculation ratio in the range from 0 to 300% (Linear Velocity increased 19.5m/d to 78m/d). The system efficiency of denitrification , nitrification over 95% respectively. Total nitrogen and COD removal range from 54.6%(recirculation 0%) to 92.3%(recirculation 300%) and 10% to 62.5%, respectively.Keywords: Advanced treatment , Biofilter, Nitrogen removal, Two combined denitrification/oxic filter
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1981