توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Managing Corrosion of Outer Surface of Automotive Steel Fuel Tank by Polymeric Coating
نویسنده(ها): ، ،
اطلاعات انتشار: دومین کنفرانس بین المللی رنگ و پوشش خودرویی، سال
تعداد صفحات: ۱۵
As new generation of automotive fuel tank, Sn–%8Zn alloy coated steel sheet are used to manufacture the fuel tank. In this research a modified procedure in order to increase the corrosion and erosion resistance of the Sn–Zn alloy coated steel sheet by using conventional polymeric coating has been contrived. This polymeric coating fulfills enough compatibility with the alloy coating in regard to its typical
applications. Several samples are prepared from tin–zinc alloy coated steel sheet with ferrous phosphate, Tricationic phosphate and without any phosphate as pretreatments in addition to polymeric coatings such as Epoxy, Poly Urethane, Polyester and Polyester–Epoxy. For consideration the interaction of paint coating on tin–zinc alloy layer the samples are subjected to some tests such as salt spray,
gasoline resistance, moisture resistance, chipping, adhesion, impact, cupping, hardness and microscopic test. As results of investigation, by using Poly ester – epoxy paint with Fe phosphate pretreatment on the tin–zinc coating, the most considerable improvement in corrosion resistance has been reached as well as desirable mechanical and physical properties. Keywords: corrosion, erosion,polymeric coating, pretreatment process, tin–zinc alloy coating.<\div>

۲Direct Torque Control of PWM Current–Source–Inverter–Fed Induction Motor
نویسنده(ها): ،
اطلاعات انتشار: بیست و چهارمین کنفرانس بین المللی برق، سال
تعداد صفحات: ۱۱
In this paper, a novel method for direct torque control of induction motor is proposed. This method is based on direct torque control with pulse width modulation of current source inverter (DTC–PWM–CSI) Using simulink\matlab simulators for its performance assessment. The proposed control system is realized based on statorflux– oriented reference. It uses the same method as direct torque control drive systems with voltage source inverter (DTC–VSI) to estimate the stator flux and electromagnetic torque, therefore only needs the stator resistance to control the motor. In this method, stator current components are calculated to directly control the stator flux and electromagnetic torque. Simulation results show the excellent performance of this system. Using simulations, the proposed method is also compared with the DTC–VSI system, and it is shown that the proposed method improves the Induction motor performance and decreases the inverter switching losses.<\div>

۳USING INDIGAU ASSET MANAGEMANT TOOL FOR PRIORITIZING REHABILITATION PROGRAMS OF SEWAGE NETWORK OF CAEN–LA–MER
نویسنده(ها): ، ، ،
اطلاعات انتشار: کنفرانس بین المللی آب و فاضلاب، سال
تعداد صفحات: ۱۵
An increasing concern of water and wastewater utilities in next years is retrofitting of existing networks which is called asset management. The sewage segments are subject to destructive constraints that bring about inev itably their degradation . Utilities will therefore have to ensure renewal of their networks and to support the heavy investment loads. A national French R&D program (RERAU, 1999–2004), which is mainly devoted to the description and construction of a set of criteria for prioritizing the rehabilitation of sewerage systems takes into account a wide range of possible causes of malfunction and dysfunction of a section by using information obtained from complementary sources: visual inspections of sewer segments, network monitoring and etc. A new R&D program (INDIGAU, 2007–2010) is dedicated to calibration and experiments of models that were defined within the RERAU program . An online program then was developed to ease the utilization of this methodology. In this artide these R&D programs will be described briefly and then the results of first implementation of INDIGAU on a real case will be reported . This program was applied on about 10% of network which is a real renovation in terms of sewage network asset management<\div>

۴A Comparative Study of PID and Fuzzy Logic Controller for a Magnetic Suspension System
نویسنده(ها): ، ،
اطلاعات انتشار: بیستمین کنفرانس مهندسی برق ایران، سال
تعداد صفحات: ۶
In this paper the application of two different types of controller ,PID and Fuzzy logic controller, on a magnetic suspension system are compared. Fuzzy logic controller (FLC)is an attractive alternative to existing classical or modern controllers for designing the challenging Non–linear control systems. It does not require any system modeling or complexmathematical equations governing the relationship between inputs and outputs. Fuzzy rules are very easy to learn and use,even by non–experts. It typically takes only a few rules to describe systems that may require several lines of conventionalsoftware code, which reduces the design complexity. By considering these advantages, this paper presents the design and analysis of a FLC controller for the magnetic levitation system. Additionally, a classical PID controller is also designed to compare the performance of both types of controllers. Results reveal that FLC found to give better transient and steady state results compare to the classical PID.<\div>

۵An intelligent scenario for methane hydrate formation at different thermodynamic conditions
نویسنده(ها): ، ،
اطلاعات انتشار: سومین کنفرانس تخصصی ترمودینامیک، سال
تعداد صفحات: ۶
A feed forward artificial neural network (ANN) with Levenberg–Marquardt training algorithm was developed to predict the pressure of methane hydrate three phase equilibria. Pressure of methane hydrate formation depends on temperature, type and amount of salinity. These variables are considered as the input of ANN model, and the output of model was compared with experimental data. Statistical parameters r (regression) and MRE (mean relative error) are employed as evidence to value the operation of model. By comparing the results, it can be concluded that ANN predictions is a good approximate for prediction of methane hydrate phase equilibria.<\div>

۶an investigationof welded AISI 4130 steel behavior during tensile deformation using acoustic emission technique
نویسنده(ها): ،
اطلاعات انتشار: کنگره بین المللی جوش و روشهای اتصال، سال
تعداد صفحات: ۶
metallurgical welding joints are extensively used in the fabrication industry including ships offshore structures steel bridges and pressure vessels when welding a long butt–welded joint residual stresses and distortions can occur near the weld bead due to localized heating by the welding process and subsequent rapid cooling high residual stresses in regions near the weld may promote brittle fractures fatigue or stress corrosion cracking residual stresses in the base plate may reduce the bckling strength of the structure members the use of fracture mechanics enables a critical defect size in a structure to be specified at a given operating stress provided that the fracture toughness and yield properties of the material are known acoustic emission technique AET is widely used to characterise the deformation and fracture processes in materials .<\div>

۷Kinetic study of decolorization of Reactive Yellow 84 by potassium peroxydisulfate
نویسنده(ها): ، ،
اطلاعات انتشار: چهاردهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۴
The decolorization of Reactive Yellow 84 (RY84) was investigated by potassium peroxydisulfate in laboratory scale experiments. The effects of operating parameters, such as, the initial concentrations of potassium peroxydisulfate and RY84 were investigated. The increase of initial peroxydisulfate concentration increases the decolorization rate. This increase is due to the enhanced production of sulfate and hydroxyl radicals. The decrease in decolorization efficiency with increasing initial RY84 concentration has been observed. The results showed that the maximum decolorization efficiency (97%) was achieved with 4mM potassium peroxydisulfate, 5 ppm RY84 and temperature 30oC. The decolorization kinetic of RY84 followed second–order<\div>

۸Interlaminar Fracture Energy of Glass\ Epoxy Composite Laminate under Mode II Delamination Using Sentry Function
نویسنده(ها): ، ،
اطلاعات انتشار: دوازدهمین کنفرانس ملی مهندسی ساخت و تولید ایران، سال
تعداد صفحات: ۴
Three modes of fracture are achieved for Delamination, mode I, II and III, in which mode II is of a great importance. It depends on stacking sequence, material properties, production process and so on, which are measured by mode–II interlaminar fracture energy (GIIc). In this work, End Notch Flexure test (ENF), through Acoustic Emission (AE) method is used to simulate mode II interlaminar fracture and damage evolution. In this way, based on AE events and mechanical properties of glass\epoxy composite material, the mode II interlaminar fracture toughness, GIIc, is investigated. Also, the influence of inplane fiber orientation on fracture behavior of interfaces: [0\90], [0\45], [–45\45], with quasi–isotropic laminates and [0\90] With angle ply laminates, are studied. The sentry function is used to study the delamination process and to evaluate the delamination fracture toughness in mode II. Consequently, it is shown that the presented method to obtain GIIc through employing AE was useful.<\div>

۹Biosorption of Nickel(II) from Aqueous Solution by Dead Fungal Biomass of Aspergillus awamori
نویسنده(ها): ، ،
اطلاعات انتشار: اولین همایش تخصصی محیط زیست، انرژی و صنعت پاک، سال
تعداد صفحات: ۶
During the last two decades, extensive attention has been paid on the management of environment of environmental pollution causal by hazardous materials such as heavy metals in the soil and water. Biosorption is a process which represents a biotechnological innovation as well as a cost effective excellent tool for removing heavy metals from aqueous solution. The aim of present study was to evaluate for the first time the biosorption potential of dead fungal biomass Aspergillus awamori to remove Nickel (II) from aqueous solution in batch studies. And experimental parameters affecting the biosorption process such as PH level,contact time,initial metal concentration were evaluated.<\div>

۱۰Multiscale Composites Based on CNFs\Epoxy\UHMWPE Fiber: Interfacial Properties
نویسنده(ها): ،
اطلاعات انتشار: اولین همایش ملی تکنولوژی های نوین در شیمی و پتروشیمی، سال
تعداد صفحات: ۸
In this study, the effect of epoxy matrix modification with different carbon nanofiber loadings consisting of 0.5, 1.0 and 1.5 wt. % on interfacial shear strength of epoxy\ultra–high molecular weight polyethylene fiber composites was investigated. In this research, UHMWPE fiber surface was treated with glycidyl methacrylate as much as 5% by weight. Then, the success of the grafting was proved with attenuated total reflectance–infra red. As the fiber was treated, the effect of surface treatment on morphology of fiber surface was evaluated by scanning electron microscopy. Along with modifying fibers, epoxy resin was modified with carbon nanofibers and dispersion of carbon nanofibers in the resin was investigated by optical microscopy. Afterwards, in order to investigate the changes in surface wetting and adhesion between the fiber and matrix, microbond test and fiber–matrix contact angle measurements of the different samples were accomplished. The results showed that the chemical process of grafting glycidyl methacrylate on the fiber surface increased the fiber surface roughness. Microbond test results revealed that the simultaneous modification of fiber surface with 5 wt. % of GMA monomer and matrix with 0.5 wt. % of carbon nanofibers considered as the maximum amount of improvement as much as 319 percent. By comparing microbond and contact angle results, synergetic effect of fiber treatment and matrix modification on improving interfacial adhesion was proved and the highest interfacial adhesion and lowest contact angle were observed as the fiber and matrix were treated at the same time.<\div>

۱۱LABORATORY SCREENING OF INHIBITORS FOR REMOVAL OF ASPHALTENE DEPOSITS
نویسنده(ها): ، ،
اطلاعات انتشار: سومین کنفرانس بین المللی نفت، گاز و پتروشیمی، سال
تعداد صفحات: ۹
One of the most severe problems during production from heavy crude oil reservoirs is the formation of Asphaltene Precipitation and Deposition is a serious problem which can reduce the oil recovery by reducing reservoir permeability and altering the wettability. It can plug wells and flow lines through deposition and also cause separation difficulties at the separation facilities. So one of the economical ways to prevent such incidents is using of the chemicals with different structure and functional group which is called Asphaltene inhibitor. In this study, three commercial and four non–commercial inhibitors were investigated. An extensive literature survey was done, then effect of functional groups and structure of inhibitors on Asphaltene precipitation were studied and it seems clear that the nature of Asphaltene (structure and amount of impurities presented) has a significant impact on the selection of inhibitors. Static and dynamic tests were designed for evaluation of inhibitors and existence of hydrogen bonding, π–π interaction and acid–base interaction mechanisms were confirmed. It was shown that salicylic acid with extra OH group has better efficiency in reduction of Asphaltene than benzoic acid. The results suggest that 600 ppm of CTAB was approximately optimum concentration for the studied crude oil. Effect of chosen inhibitors on Asphaltene precipitation and consequently deposition in porous media was investigated<\div>

۱۲A New Ring Oscillator with Dual Voltage\Current Control
نویسنده(ها): ، ،
اطلاعات انتشار: اولین کنفرانس بین المللی دستاوردهای نوین پژوهشی در مهندسی برق و کامپیوتر، سال
تعداد صفحات: ۵
A new Temperature compensated Ring Oscillator is presented. This CMOS ring oscillator consists of five current starved stage which is fed by a voltage and a current reference. In this paper a new method based on previous works has been proposed, in which required Temperature characteristic is imposed to the oscillator. The oscillation frequency of the proposed oscillator is 14.5 MHz and the simulation results in CMOS 0.18μm technology with a 1.8– V power supply showed that the temperature coefficient is 31.1 ppm\oC in the Temperature range of –15 ºC to 65 ºC. The total power consumption of circuit is 587 μW.<\div>

۱۳Quantitative structure–activity relationship study of P2X7 receptor inhibitors using combination of principal component analysis and artificial intelligence methods
نویسنده(ها): ،
اطلاعات انتشار: Research in Pharmaceutical Sciences، دهم،شماره۴(پياپي ۳۱)، ۲۰۱۵، سال
تعداد صفحات: ۱۹
P2X7 antagonist activity for a set of 49 molecules of the P2X7 receptor antagonists, derivatives of purine, was modeled with the aid of chemometric and artificial intelligence techniques. The activity of these compounds was estimated by means of combination of principal component analysis (PCA), as a well–known data reduction method, genetic algorithm (GA), as a variable selection technique, and artificial neural network (ANN), as a non–linear modeling method. First, a linear regression, combined with PCA, (principal component regression) was operated to model the structure–activity relationships, and afterwards a combination of PCA and ANN algorithm was employed to accurately predict the biological activity of the P2X7 antagonist. PCA preserves as much of the information as possible contained in the original data set. Seven most important PC’s to the studied activity were selected as the inputs of ANN box by an efficient variable selection method, GA. The best computational neural network model was a fully–connected, feed–forward model with 7−7−1 architecture. The developed ANN model was fully evaluated by different validation techniques, including internal and external validation, and chemical applicability domain. All validations showed that the constructed quantitative structure–activity relationship model suggested is robust and satisfactory.
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