توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Investigation on the Structural Properties of Nanocrystalline MgAl2O4 Spinel Powder Synthesized by Surfactant–Assisted Precipitation Route
اطلاعات انتشار: دوازدهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۸
In this paper nanocrystalline MgAl2O4 spinel powders were synthesized with a new synthesis method by co–precipitation method with CTAB as surfactant. The prepared samples were characterized by X–ray diffraction (XRD), N2 adsorption (BET), thermal gravimetric and differential thermal analysis (TGA\DTA), Fourier–Transform Infrared Spectroscopy (FT–IR). The effects of surfactant to metal molar ratio on the structural properties of the samples were investigated. The obtained results showed that the addition of surfactant have a significant effect on the specific surface area and thermal stability of the samples.<\div>

۲MAKING A BLEACHING CLAY BASED ON THE BENTONITIC CLAYS
نویسنده(ها):
اطلاعات انتشار: دوازدهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۸
Fuller’s earth and acid activated Bentonite clays are used for decolorizing of dark oils. They are largely used for the industrial processing of vegetable, animal and mineral oils. The purpose of this paper is, to execute investigations on four Bentonite samples to determine the possibility of its activation by sulfuric acid in order to produce industrial samples of bleaching earth for bleaching tests with vegetable and mineral oil.<\div>

۳New Synthesis method of Nanocrystalline MgAl2O4 Spinel by Using Ethylene Diamine As Precipitation Agent
نویسنده(ها): ، ، ،
اطلاعات انتشار: دوازدهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۶
In this paper nanocrystalline MgAl2O4 spinel powders were synthesized with a new synthesis method using ethylene diamine as precipitation agent. The prepared samples were characterized by X–ray diffraction (XRD), N2 adsorption (BET), thermal gravimetric and differential thermal analysis (TGA\DTA), Fourier– Transform Infrared Spectroscopy (FT–IR). The obtained results showed a nanocrystalline structure with relatively high surface area and mesoporous structure. Increasing in calcinations temperature slightly decreased the specific surface area and increased the crystallite size.<\div>

۴STUDIES ON CARBON DEPOSITION IN CO2 REFORMING OF METHANE OVER NICKEL CATALYSTS
نویسنده(ها): ، ،
اطلاعات انتشار: دوازدهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۹
Carbon deposition over nickel catalysts in methane reforming with carbon dioxide is one of the most important topics in catalysis. Carbon formation may increase the pressure drop, crush the catalyst pellets, block the active nickel surface and decrease the life time of catalyst. In this paper the carbon
deposition over nickel catalyst supported on zirconia has been investigated in methane reforming with carbon dioxide. The microscopic analysis, along with TPH and TPO analyses confirmed that the CO disproportionation is one of the main steps for carbon generation in CO2 reforming.<\div>

۵Synthesis of Nanostructured Magnesium Oxide with Polyvinyl alcohol and Sucrose as MSurfactant and Chelating Agent
نویسنده(ها): ، ،
اطلاعات انتشار: ششمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۷
In this paper nanostructured magnesium oxide was prepared by a new wet chemical method using polyvinyl alcohol and sucrose as surfactant and chelating agent. The synthesized powders were characterized by X–ray diffraction (XRD), Fourier Transform Infrared (FTIR), Thermal gravimetry (TG), Differential thermal gravimetry (DTG) and Derivative differential thermal (DDTA) analyses. The obtained results showed that the increasing in sucrose\MgO molar ratio decreased the crystallite size. Increasing in calcination temperature also increased the crystallite size due to sintering of MgO crystals.<\div>

۶Overview on application of multivariate techniques in environmental engineering
نویسنده(ها): ،
اطلاعات انتشار: پنجمین همایش تخصصی مهندسی محیط زیست، سال
تعداد صفحات: ۸
Recent advances in multi–sensor technology and electronics created a situation where huge amount of data (in both space and time) can be obtained in various disciplines including environmental engineering. These data are often multi–dimensional with numerous hidden properties. The univariate statistical analysis, generally implemented to treat such data, could not uncover the complex and hidden properties of them. Multivariate techniques are the key puzzle in this struggle. They are unbiased techniques which can help indicate natural associations between samples and\or variables, thus highlighting information not available at first glance. The multivariate statistical techniques and the associated exploratory spatial data analysis (ESDA) are the appropriate tools for a meaningful data reduction and interpretation of multi–constituent chemical, physical, and biological measurements. In this paper, the usefulness of such tools as principal component analysis (PCA), factor analysis (FA) and cluster analysis (CA) will be highlighted regarding their potential to discover the hidden properties of data in various branches of environmental engineering including surface water, groundwater, soil, and air. Careful review of literature showed that PCA has been widely used in geochemical applications to identify pollution sources and to separate natural versus anthropogenic activities in aqueous, soil and air environment, as well as examination of spatial and temporal patterns of contamination and also identification of the most informative monitoring stations. The associated procedure of factor analysis with its robust rotation ability could facilitate the clean up of principal components. CA is an efficient means to recognize groups of samples that have similar chemical and physical characteristics. It is concluded that multivariate statistical techniques could be considered as an efficient tool to display complex relationships among many objects and assist the decision makers in managing and controlling pollution and provide an effective overview of hot spots where intensified monitoring activities are required.<\div>

۷A Primary Feasibility Study of Wind Farms in Kerman
نویسنده(ها): ، ،
اطلاعات انتشار: نخستین همایش ملی انرژی باد و خورشید، سال
تعداد صفحات: ۱۴
In this paper a brief introduction to wind potential study and assessment is presented and some probable windy areas of Kerman are introduced. The approach is based on local wind assessment stations, intuitive historical data and also the general Iranian wind atlas provided by SUNA. Importance of a feasibility study on using wind energy in such areas is illustrated by discussing economic and environmental benefits of installing wind farms.<\div>

۸Capabilities and limitations of tourism development in Shiraz
نویسنده(ها): ، ، ،
اطلاعات انتشار: اولین همایش بین المللی مدیریت گردشگری و توسعه پایدار، سال
تعداد صفحات: ۱۸
Country in terms of potential tuorisem especially one of the few countries in the field of tourism is superior. Shiraz sample cities are the cradle of ancient customs and rituals are cultural and historical Persia. The Holy Land is a great foster care because the secret from Khaja Hafez, Sa'adi Shirazi, Mulla Sadra, and .. that Sybuvyh passing on the rich culture founded in Shiraz and Fars have been. Shiraz Attractions important historical buildings, gardens, old and very important cultural venues such as the tomb of Hafez and Saadi is undoubtedly the most important tourist attractions in Iran and abroad to attract tourists who are properly planned and organized to form a single Tourism (apart from Cultural Heritage, Tourism and Resources Manual) can be the city's tourism Iran turned into pole, causing the Economic, Social and Cultural Shiraz will. Descriptive study – is applied through the review and from field observations and a library of models and potential production index visit CPGI, MIOSSEC agent and five rings have been The results highlight the capabilities of actual and potential tourism Shiraz is rich with culture and historical background of this city and doing proper planning and the credit can be ideal to attract tourists and thus reach sustainable development.<\div>

۹Fabrication of composite layer containing TiN and TiC particles on the surface of steel by TIG
نویسنده(ها): ،
اطلاعات انتشار: سومین کنفرانس بین المللی عملیات حرارتی مواد، سال
تعداد صفحات: ۷
The possibility of fabrication of composite layer containing TiN and TiC on the surface of AISI 1045 steel by TIG (Tungsten Inert Gas) welding process was examined. In order to do this, once the powder of Ferro–Titanium and sodium silicate adhesive by blowing nitrogen and another time a powder containing graphite powder and Ferro– Titanium were bound on the surface of steel in pre deposited state and then surface melting through TIG process was conducted. Microstructural examination by optical microscope and SEM (scanning electron microscope), micro hardening and XRD (X–ray diffraction) were conducted on the created surfaces. The results elicit the formation of cubic titanium nitride through a reaction between Ferro–Titanium and Nitrogen and cubic titanium carbide through a reaction between graphite powder and Ferro–Titanium in the melt pool. The studies showed that the carbide and nitride particles were uniformly scattered in the composite coat. Since these particles were created and uniformly scattered in the matrix, the created composite films had high levels of hardness (about 50 HRC).<\div>

۱۰allocating scarse saline ground water resources to competitive demands in kohpayeh –segzi plain isfahan ,Iran
نویسنده(ها): ،
اطلاعات انتشار: نهمین کنگره بین المللی مهندسی عمران، سال
تعداد صفحات: ۹
the cornerstone of successful planning for allocating limited ground water resources to competitive public demand is to maximize the net benefit with due consideration on sustainable development in the case of unconventional saline and brackish ground water resources optimum allocation depends on compatibility of water quality and usage criterion along with the least ecosystem threat after satisfying those conditions benefit to cost ratio has to be taken into account.this objective calls for adequate knowledge of spatiotemporal ground water resources variability in this study optimal saline ground water allocation of shallow aquifer of kohpayeh sagzi plain isfahan iran to prevalentcompetitive practices is carried out.<\div>

۱۱Application ofWireless Power Transfer in Pitch Angle Control in Wind Turbines
نویسنده(ها): ، ، ،
اطلاعات انتشار: دومین کنفرانس بین المللی سالانه انرژی پاک، سال
تعداد صفحات: ۶
This paper investigates the use of Wireless Power Transfer (WPT) technology as a substitute for mechanical slip rings in pitch angle control for windturbines. Due to wear and tear problems and high maintenance costs of slip rings, contactless slip rings can be used instead of conventional mechanical sliprings. Contactless slip ring is a maintenance–free alternative and doesn’t have the friction and heating problem that conventional slip rings have. In this paperafter explaining the importance of pitch angle control, wireless power transfer technology is introduced and implementing WPT in pitch angle control system isinvestigated. For a better understanding of wireless power transfer, simulation of a WPT electronic circuitis performed and maximum efficiency condition is studied. Finally, it is concluded that implementing contactless slip ring instead of common slip ring inwind turbine is feasible<\div>

۱۲SINTERING– A CATALYTIC CHALLENGE IN HETEROGENEOUS CATALYSIS
نویسنده(ها): ،
اطلاعات انتشار: اولین همایش ملی تکنولوژی های نوین در شیمی و پتروشیمی، سال
تعداد صفحات: ۷
Catalysts have been used commercially from many years ago and are one of the most important parts of the chemical processes. In this paper the deactivation of heterogeneous catalysts bysintering, an irreversible, slow and inevitable phenomenon and its mechanisms and kinetics arediscussed. Thermal, or thermo–chemical degradation, is probably the main and greatest cause for the deactivation of catalysts, especially for late transition metal particles dispersed on oxides or other supports and begins in the temperature area of 800°–900°C, or in some cases even at lowertemperatures, depending on the materials used.<\div>

۱۳More Relaxed Non–quadratic Stabilization of Takagi–Sugeno Fuzzy Models by Determination of Membership Function Information
نویسنده(ها): ، ، ،
اطلاعات انتشار: همایش ملی مهندسی برق و توسعه پایدار با محوریت دستاوردهای نوین در مهندسی برق، سال
تعداد صفحات: ۸
In this paper, a systematic approach is presented for more relaxed stability analysis conditions and fuzzy controller design for Takagi–Sugeno systems in the form of LMIs. This approach is based on the idea of non–quadratic Lyapunov function and one assumption. In this paper, the upper bounds of the time derivative of membership functions are considered as LMI variables which lead to more relaxed stability analysis conditions and wider stability region. Several numeric examples and comparisons illustrate the effectiveness and superiority of the proposed method.<\div>

۱۴Vibration Control of an Optical Device
نویسنده(ها): ، ، ،
اطلاعات انتشار: کنفرانس دو سالانه بین المللی مکانیک جامدات تجربی، سال
تعداد صفحات: ۸
The goal of this research is vibration damping of an optical device. This study considers the modeling and identification of a nonlinear hysteretic system, wire–rope isolator. A shock and vibration absorber commonly used in naval vessel and airplanes is the wire–rope spring. Wire rope springs show a good damping performance due to rubbing and sliding friction between the wire rope strands. Cyclic loading quasi static tests are carried out on a wire–rope isolator in order to experimentally obtain its hysteretic behavior using simple tensile\compression equipments. The wire–rope isolator exhibits asymmetric hysteresis loop, which posses a hardening loading overlap in the loading curves. The Bouc–Wen model is a nonlinear hysteresis model on a phenomenological base that is one of the most accepted smoothly varying differential models in the engineering field. Because of overlapping and time–history–dependent of the hysteresis force a modified version of the original Bouc–Wen model is presented. An optimization problem is formulated in order to identify the model parameters from the experimental data of the quasi static tests using Genetic Algorithm. Finally, the dynamic response behavior of a wire–rope isolation system is evaluated. In order to reduce the vibration amplitude, type and number of wire–rope isolator can be changed.<\div>

۱۵Synthesis of Mesoporous MgAl2O4 Spinel Nanopowder with High Surface Area
نویسنده(ها): ، ، ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۶
In this research, mesoporous nanocrystallite magnesium aluminate powder with high specific surface area was synthesized by a simple co–precipitation method with the addition of pluronic P123 triblock copolymer as surfactant. The prepared samples were characterized by X–ray Diffraction (XRD), N2 adsorption (BET) and Scanning electron microscopy (SEM). The effects of calcination temperature on the structural properties of the samples were investigated. The results showed that with increasing in calcination temperature from 600 to 800 ˚C increased the crystallite sizes and decreased the specific surface area in the range of 183–124 m2g–1.<\div>

۱۶Thermodynamic Analysis of Combined CO2 and O2 Reforming of Methane to Produce Syngas
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۶
In this paper, a thermodynamic analysis of Combined CO2 and O2 reforming of methane, using the Gibbs free energy minimization method, has been carried out. Mathematical relationship Lagrange’s undetermined multipliers was applieded and nonelinear equations system was obtained. The nonlinear programming model was implemented and the MATLAB (MATLAB 7.80, R2009a)solver was used to solve the equations. The thermodynamic equilibriums of the combined CO2 and O2 reforming of methane are abviously affected by CH4:CO2:O2 feed ratios and operating temperatures. Optimized conditions for CH4 conversion, hydrogen and monoxide production are temperatures between 1000 to 1100 K and best CH4:CO2:O2 feed ratio are within the range of 1:1:0.2–1:1:0.4.<\div>

۱۷Improving Energy Efficiency in Pulp and Paper Industry,Using a CCHP System
نویسنده(ها): ، ، ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۹
Combined Cooling, Heating and Power (CCHP) system is a cogeneration technology that integrates an absorption cycle to produce power, heating and cooling, simultaneously. It issometimes referred to as tri–generation system. In this study, the implementation of a CCHP system in a pulp and paper industry is studied, which consists of a gas turbine, a power generator, a HRSG system and an absorption heat pump (AHP) driven by the steam discharged from a steamturbine. Pinch analysis is applied to find the appropriate placement of the proposed CCHP system in black liquor concentration section of the process. Thermo flow and Aspen plus softwares are used to simulate the turbine cycle and AHP, respectively. The concentration section is alsosimulated by Aspen plus software. Having implemented the proposed CCHP system, both heatingand cooling requirements are reduced by 5.8 MW. This scheme also could produce 37.3 MW of electrical power, with the payback of 1.1 years<\div>

۱۸Carbon Monoxide Oxidation over Iron – Cobalt Mixed Oxide Nanocatalysts
نویسنده(ها): ، ، ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۸
In this paper low temperature CO oxidation over iron–cobalt mixed oxide nanocatalysts with different Co\Fe molar ratios was investigated. The nanocatalysts were prepared with a facile precipitation method. The prepared samples were characterized by X–ray diffraction (XRD), N2 adsorption (BET), Thermal gravimetric and differential thermal analyses (TGA\DTA) and Transmition electron microscopy (TEM) techniques. The BET results revealed that the samples showed a mesoporous structure and decreasing in Co\Fe molar ratio shifted the pore size distributions to smaller values. The TEM analysis showed a nanostructure for Co\Fe =1\5 sample with crystallite sizes smaller than 20 nm. The catalytic results showed that the addition of Co to iron oxide even in small amount has a dramatic effect on increasing CO conversion at lower temperatures<\div>

۱۹CO Oxidation over Iron Oxide Nanocatalysts Prepared via Different Methods and Precursors
نویسنده(ها): ، ، ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۶
In this work iron oxide nanoparticles were prepared by a simple precipitation technique with using different precursors and various surfactants during synthesis. The prepared samples were characterized by X–ray diffraction (XRD), N2 adsorption (BET) and Scanning electron microscopy (SEM) techniques. The results show that the activity of iron catalysts in CO oxidation reaction was significantly affected by preparation method and type of precursors. The obtained results indicated that using nitrate precursors and reverse precipitation method for iron oxide preparation have a positive effect on the structural and catalytic properties of iron oxide in CO oxidation reaction<\div>

۲۰Effect of Calcination Temperature on Structural Properties of Iron–Cobalt Nanocatalysts in Low–Temperature CO Oxidation
نویسنده(ها): ، ، ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۷
Iron–Cobalt nanoparticles (Co\Fe molar ratio: 1\5) have been prepared by a simple co–precipitation method and employed as catalyst in low–temperature CO oxidation. The prepared catalysts were characterized by X–ray diffraction (XRD), N2 adsorption (BET), Transmition electron microscopy (TEM) techniques. The results showed that the calcination temperature has a significant effect on catalytic performance of prepared catalysts. Increasing in calcination temperature increased the crystallite and particle size and decreased the specific surface area which caused a decrease in catalytic activity of prepared catalysts.<\div>

۲۱the importance of the precursor to prepare high temperature water –gas shift reaction catalysts
اطلاعات انتشار: پانزدهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۴
Fe–Cr–Cu catalysts were prepared and studied in regard to their performance in the high–temperature water–gas shift reaction (HTS), which is the key step of hydrogen and ammonia industrial plants. In this work, the effect of the precursor on the activity of magnetite–based catalysts prepared by precipitating a composition containing divalent and trivalent iron compounds and a modifier trivalent chromium with a base, was studied in terms of CO conversion. The production of catalysts in their active form avoids the step of activation prior to use, in industrial processes. Sulfates and chlorides were the selected precursors. A commercial Fe–Cr based WGS catalyst was used for comparison. Catalysts were characterized using BET surface area measurements, temperature–programmed reduction (TPR) and X–ray fluorescence (XRF). According to the obtained results, the materials prepared with sulfate showed lower specific surface areas but they were more active than those obtained from chloride and the commercial one and there were three reduction peaks for all the samples in TPR results<\div>

۲۲Low Temperature CO Methanation over High Surface Area Ni\γ–Al2O3 Nanocatalysts for CO Removal of H2–rich Stream
نویسنده(ها): ، ، ،
اطلاعات انتشار: پانزدهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۶
In this work, nickel catalysts supported on high surface area mesoporous nanocrystalline gamma alumina were prepared and employed in CO methanation reaction. The γ–Al2O3 with high surface area and mesoporous structure was prepared by precipitation method and employed as support for preparation of nickel catalysts with different nickel contents. The prepared samples were characterized by XRD and BET techniques. The results showed that the optimized γ–Al2O3 possessed a mesoporous nanocrystalline structure with a high surface area of 328 m2.g–1. The catalytic results revealed that 25 wt.% Ni\Al2O3 catalyst exhibited the highest catalytic activity and showed 100% CO conversion at temperatures as low as 240°C.<\div>

۲۳Effect of Iron Precursor on the Preparation of Mesoporous Nanocrystalline Chromium Free Fe2O3–Al2O3–NiO Catalyst for High Temperature Water Gas Shift Reaction
نویسنده(ها): ، ،
اطلاعات انتشار: دومین کنفرانس بین المللی نفت، گاز و پتروشیمی، سال
تعداد صفحات: ۷
Mesoporous nanocrystalline Cr–free Fe–Al–Ni catalysts were synthesized by coprecipitation method and employed in high temperature water gas shift reaction. The effects of iron precursors such as ferric sulfate and ferric nitrate on the structural and catalytic properties of the prepared catalysts were investigated. The catalysts were characterized by powder X–ray diffraction (XRD), N2 adsorption (BET), Temperature programmed reduction (TPR) and transmission electronmicroscopy (TEM) techniques. The TEM analysis showed the crystallite size smaller than 15 nm for the catalyst prepared with nitrate precursor. The catalytic results showed that the prepared catalyst with nitrate precursor exhibited higher catalytic activity than the catalyst prepared with sulfate precursor and the commercial chromium containing one. In addition this catalyst possessed a high surface area of 177.4 m2 g–1 with an average pore size of 4.4 nm with a high stability during 20 h time on stream.<\div>

۲۴Growth response and tail–muscle fatty acid quality of Pacific white shrimp, Litopenaeus vannamei (Boone) fed with diets containing different levels of rice protein concentrate
نویسنده(ها): ، ، ،
اطلاعات انتشار: IRANIAN JOURNAL OF FISHERIES SCIENCES، چهاردهم،شماره۱، Jan ۲۰۱۵، سال
تعداد صفحات: ۱۳
The effect of five isonitrogenous diets (36.6% protein), formulated by replacing 0, 25, 50, 75, and 100% of fish meal (FM) with rice protein concentrate (RPC), was investigated on the growth and tail–muscle fatty acid (FA) quality of juvenile Pacific white shrimp, Litopenaeus vannamei. The feeds were fed to shrimp (initial weight of 6.99 ± 0.08 g) five times daily to apparent satiation for 60 days. Final weight of shrimp fed with FM, 25 and 50% RPC was higher than that of shrimp fed with 75 and 100% RPC. Survival in shrimp was not significantly affected by dietary protein source and level (p>0.05). Regarding FAs, ∑n6 and PUFA increased significantly as the RPC levels increased, but the n–3\n–6 ratio, EPA+DHA, MUFA, SFA and ∑n3 were significantly declined (p0.05). However, tail–muscle FA composition reflected the inclusion of plant protein. Lipid quality indices (AI and TI) showed significant variation, but were very favourable for the consumers’ health. The present study suggests that RPC can replace FM up to 50% in diets for L. vannamei with no significant effect on the growth, but a decreasing trend in quality of tail–muscle FAs was observed when the RPC level increased.
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