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    Applying alloyed metal nanoparticles to enhance solar assisted water splitting

    , Article RSC Advances ; Vol. 4, issue. 87 , 2014 , pp. 46697-46703 Naseri, N ; Sangpour, P ; Mousavi, S. H ; Sharif University of Technology
    Considering hydrogen as a future fuel, development of clean approaches based on solar energy conversion is the main human challenge. Here, for the first time, TiO2 photoanodes are decorated with Au-Ag alloy nanoparticles for efficient photoelectrochemical water splitting. The photoanodes were synthesized using a one-step co-sputtering method. The single surface plasmon resonance peak at 540 nm and also the observed shifts in photoelectron binding energies are fingerprints of homogenous alloyed nanoparticles. Scanning electron microscopy revealed the formation of nearly 40 nm particles on the surface, which was also verified by the simulation of the film's optical absorption. Photocurrent... 

    A novel hybrid systemic modeling into sustainable dynamic urban water metabolism management: Case study

    , Article Sustainable Cities and Society ; Volume 85 , 2022 ; 22106707 (ISSN) Nezami, N ; Zarghami, M ; Tizghadam, M ; Abbasi, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Over the past few years, due to increasing population, limited water resources, and other pressures on the urban water systems (UWS), urban water management has become a major concern for urban policymakers to develop efficient management solutions. In this study, a new hybrid model called sustainable dynamic urban water metabolism management (SDUWMM) is presented, based on urban water metabolism and system dynamics. Isfahan's UWS has been modeled by SDUWMM and its conditions have been simulated until 2041. SDUWMM considers effective internal relationships of the UWS components such as population, climate change, water supply and demand, infrastructures condition, water price, costs and... 

    Optimum design of R.O. membrane by using simulation techniques

    , Article Desalination and Water Treatment ; Volume 9, Issue 1-3 , 2009 , Pages 189-194 ; 19443994 (ISSN) Afrasiabi, N ; Ehteshami, M ; Ardakanian, R ; Sharif University of Technology
    Increasing demand of fresh water, and limitation water resources, with respect to world economic growth brings up the importance of utilization of saline water. At the current research the sensitivity analysis of ROSA was conducted. For this analysis, a single stage reverse osmosis is designed for well water specifi cation in southern Tehran under following condition: Feed fl ow: 40 m3/h and membrane Element: BW30–400 FR. The sensitivity analyses for all chemical element of base water were performed. As a result of sensitivity analysis shortest sensitivity gap, belongs to boron, and longest sensitivity gap, belongs to calcium. Which refl ects, under the same conditions, the least element to... 

    The delusive accuracy of global irrigation water withdrawal estimates

    , Article Nature Communications ; Volume 13, Issue 1 , 2022 ; 20411723 (ISSN) Puy, A ; Sheikholeslami, R ; Gupta, H. V ; Hall, J. W ; Lankford, B ; Lo Piano, S ; Meier, J ; Pappenberger, F ; Porporato, A ; Vico, G ; Saltelli, A ; Sharif University of Technology
    Nature Research  2022

    Ro brine treatment and disposal methods

    , Article Desalination and Water Treatment ; Volume 35, Issue 1-3 , Aug , 2011 , Pages 39-53 ; 19443994 (ISSN) Afrasiabi, N ; Shahbazali, E ; Sharif University of Technology
    Taylor and Francis Inc  2011
    More than 50 percent of countries in the world will likely face water stress or water shortages by 2025, and by 2050, as much as 75 percent of the world's population could face water scarcity. Desalination technologies, particularly the reverse osmosis (RO) process, have increasingly been adopted to produce freshwater from alternative sources such as seawater and brackish water due to water scarcity. However, desalination applications have always been limited by the disposal costs of RO brine and the adverse impact of brine on the receiving environment. The scope of this paper is to identify technically and commercially RO brine disposal and treatment methods such as deep well injection,... 

    Study of electrical conductivity of different water liquids and electrolytes

    , Article Australian Journal of Basic and Applied Sciences ; Volume 4, Issue 8 , 2010 , Pages 3985-3997 ; 19918178 (ISSN) Golnabi, H ; Sharifian, M ; Sharif University of Technology
    In this study electrical conductivities of pure, distilled, municipal, industrial and river water liquids along with those of different electrolyte solutions are computed at room temperature (25 °C) and compared with the experimental results. For experiment, using a measuring module both R and C value of the water samples are measured by using two different cylindrical cells. The obtained RC product for the long and short cell probes are compared for different water samples. Obtained results give the relaxation time, which is the measure of the conduction relaxation and for a good conducting medium such a time is very short. The relaxation time for the salt solution is about 0.07044 ms... 

    Numerical study on the asymmetric water entry of a wedge section

    , Article China Ocean Engineering ; Volume 18, Issue 4 , 2004 , Pages 595-604 ; 08905487 (ISSN) Seif, M. S ; Mousaviraad, S. M ; Saddathosseini, S. H ; Sharif University of Technology
    The effect of the asymmetric water entry over a submerged part of a ship on the hydrodynamic impact is investigated numerically. A wedge body is considered and the problem is assumed to be two-dimensional. The results of symmetric and asymmetric impacts are compared. The effect is found significant in the numerical simulation. The maximum hydro-dynamic pressure at a heel angle of 10 degrees becomes about 95% more than that of the symmetric entry. The result of the present work proves the importance of asymmetrical hydrodynamic impact loading for structural design of a ship. Besides, the numerical procedure is not limited to a wedge type cross section and it is possible to apply it for any... 

    The effect of asymmetric water entry on the hydrodynamic impact

    , Article International Journal of Engineering, Transactions A: Basics ; Volume 17, Issue 2 , 2004 , Pages 205-212 ; 17281431 (ISSN) Seif, M. S ; Mousaviraad, S. M ; Sadathosseini, S. H ; Sharif University of Technology
    National Research Center of Medical Sciences  2004
    The effect of ihe asymmetric water entry over a submerged part of a ship on the hydrodynamic impact is investigated numerically. A wedge body is considered 10 study and the problem is assumed to be two-dimensional. The Results of symmetric and asymmetric impacts are compared together. The effect is found significant in the numerical simulation. The maximum hydrodynamic pressure at a heel angle of 10 degrees becomes about 95% more than that of the symmetric entry. The result of the present, work proves the importance of asymmetrical hydrodynamic impact leading for structural design of a ship. Besides, the numerical procedure is not limited to a wedge type cross section and it is possible to... 

    Oil biodegradation in sea water

    , Article Iranian Journal of Science and Technology, Transaction B: Technology ; Volume 25, Issue 1 , 2001 , Pages 87-92 ; 03601307 (ISSN) Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
    Biodegradation of petroleum hydrocarbons in salt medium (SM) containing sea water by Pseudomanas sp. was investigated. Different oil hydrocarbons such as n-decane, benzene, naphthalene, paraffin, paraffin + vaseline, paraffin + kerosene, and fuel oil were used as carbon sources. Cell growth (OD) and COD were measured for evaluation of oil biodegradability. The effect of inorganic and organic nitrogen sources on COD removal revealed a 95% and 75% reduction of COD for inorganic and organic nitrogen sources, respectively  

    Low Grade Heat Driven Multi-Effect Distillation and Desalination

    , Book Rahimi, Bijan ; Chua, Hui Tong
    Elsevier  2017
    Low Grade Heat Driven Multi-effect Distillation and Desalination describes the development of advanced multi-effect evaporation technologies that are driven by low grade sensible heat, including process waste heat in refineries, heat rejection from diesel generators or microturbines, and solar and geothermal energy. The technologies discussed can be applied to desalination in remote areas, purifying produced water in oil-and-gas industries, and to re-concentrate process liquor in refineries.
    This book is ideal for researchers, engineering scientists, graduate students, and industrial practitioners working in the desalination, petrochemical, and mineral refining sectors, helping them... 

    A sustainable urban water management model under uncertainty: a case study

    , Article Management of Environmental Quality: An International Journal ; Volume 32, Issue 2 , 2021 , Pages 376-397 ; 14777835 (ISSN) Shabani, M ; Shams Gharneh, N ; Akhavan Niaki, S. T ; Sharif University of Technology
    Emerald Group Holdings Ltd  2021
    Purpose: Tackling the challenges of water scarcity requires comprehensive management according to financial, environmental and social issues. This paper aims to develop a planning approach for systematic decision-making and pay attention to uncertainties in water demand management and supply investment. Design/methodology/approach: This study presents a multiobjective optimization model to manage water resources based on the balance of supply and demand. The objectives of the model include economic, social and environmental (sustainable development) factors. The model achieves an optimal urban water portfolio by using a scenario tree. Findings: The mathematical goal programming (GP) in a... 

    Development of water conservation indicators for office buildings using Delphi method

    , Article Jordan Journal of Mechanical and Industrial Engineering ; Volume 16, Issue 2 , 2022 , Pages 247-259 ; 19956665 (ISSN) Sadi, S ; Gholami, J ; Fereydooni, M ; Moshari, S ; Sharif University of Technology
    Hashemite University  2022
    One of the main concerns in source water protection and supply relates to the savings in water consumption in the building sectors. Office buildings are responsible for a considerable amount of water consumption worldwide. Thus, regulations on office buildings' water consumption would substantially reduce water consumption in the city as a whole. In order to achieve this objective, water indicators should be determined using an appropriate method. The present study focuses on the evaluation of water consumption patterns in an office building as well as the determination of the fundamental indicators for water conservation and optimization of water consumption patterns. To design and... 

    Selective withdrawal optimization in a multipurpose water use reservoir

    , Article International Journal of Environmental Science and Technology ; Volume 16, Issue 10 , 2019 , Pages 5559-5568 ; 17351472 (ISSN) Aghasian, K ; Moridi, A ; Mirbagheri, A ; Abbaspour, M ; Sharif University of Technology
    Center for Environmental and Energy Research and Studies  2019
    Dam construction in arid and semiarid regions is generally related to the risk of increased salinity, due to water passage in contact with salty formations. Hence, it is important to take reservoir thermal and salinity stratification into account in operational rules. In the present study, a simulation–optimization model was developed to determine the amount of water release from various outlets to discharge the brine from hypolimnion layer considering the downstream water quality limitations. The most appropriate time, rate, and concentration to release brine were determined based on water consumption conditions and downstream water demand and river ecology characteristics. The proposed... 

    Role of exchange flow in salt water balance of Urmia Lake

    , Article Dynamics of Atmospheres and Oceans ; Vol. 65, issue , 2014 , pp. 1-16 ; ISSN: 03770265 Marjani, A ; Jamali, M ; Sharif University of Technology
    In this paper we examine how exchange flow in Urmia Lake plays a crucial role in dynamics of the lake. Urmia Lake, a very large hyper-saline lake of high ecological significance, is located in northwest of Iran with a 15-km causeway dividing it into north and south lakes. A 1250-m opening in the causeway near the east coast links the two lakes. The differences in mean water levels and densities of the two lakes increase in spring due to large freshwater inflows into the south lake. High evaporation dominates the lake in summer. By incorporating the results of a two-layer hydraulics theory into a mixing model of the lake, we show that the exchange flow through the opening diminishes the water... 

    The impact of connate water saturation and salinity on oil recovery and CO2 storage capacity during carbonated water injection in carbonate rock

    , Article Chinese Journal of Chemical Engineering ; 2018 ; 10049541 (ISSN) Shakiba, M ; Riazi, M ; Ayatollahi, S ; Takband, M ; Sharif University of Technology
    Chemical Industry Press  2018
    Carbonated water injection (CWI) is known as an efficient technique for both CO2 storage and enhanced oil recovery (EOR). During CWI process, CO2 moves from the water phase into the oil phase and results in oil swelling. This mechanism is considered as a reason for EOR. Viscous fingering leading to early breakthrough and leaving a large proportion of reservoir un-swept is known as an unfavorable phenomenon during flooding trials. Generally, instability at the interface due to disturbances in porous medium promotes viscous fingering phenomenon. Connate water makes viscous fingers longer and more irregular consisting of large number of tributaries leading to the ultimate oil recovery... 

    Hydrogel materials as an emerging platform for desalination and the production of purified water

    , Article Separation and Purification Reviews ; 2020 , Pages 1-20 Salehi, A. A ; Ghannadi Maragheh, M ; Torab Mostaedi, M ; Torkaman, R ; Asadollahzadeh, M ; Sharif University of Technology
    Taylor and Francis Inc  2020
    Water is the most abundant liquid on Earth, but only 2.5% of worldwide water are fresh. It is impossible to ignore the importance of water in almost every process on Earth, from the smallest bacteria life to the formation of the continents. Today, efforts for the desalination of seawater and brackish water are critical to produce drinking water. In recent years, a novel material: hydrogel, was considered in desalination processes. Interesting hydrogel applications were proposed for forward osmosis desalination, solar still, electrodialysis, and capacitive desalination. Simple and inexpensive desalination ways for drinking water production are needed. Hydrogel compounds are one of the leading... 

    Physico-chemical and biological characteristics of Sarabs (spring pools) in the Kermanshah Province of Iran

    , Article Iranian Journal of Science and Technology, Transaction B: Engineering ; Volume 30, Issue 5 , 2006 , Pages 621-635 ; 03601307 (ISSN) Khatami, S.H ; Shayegan, S. J ; Sharif University of Technology
    Sarabs (spring-fed pools) are an important natural freshwater resource in Iran where they are used for potable, agricultural and recreational purposes. A survey of 17 Sarabs was undertaken in the Province of Kermanshah to obtain data on their water quality and biology which would help inform future management of these multifunctional resources. These Sarabs differed greatly in size (50-30000m2 surface area) and were situated at altitudes of between 622 and 1697 m above sea level. The average dissolved oxygen content and pH of the water was between 4.5 and 10mg O2/1, and 6.95 and 7.6 respectively. The Sarabs differed particularly in their dissolved solids content from 100μS/cm (detectable... 

    Coating of Sewage Pipes with Appropriate Nanomaterials Aimed at Preventing Biological Growth (Algae+Biofilm)

    , M.Sc. Thesis Sharif University of Technology Nezameddin, Mahsa Sadat (Author) ; Borghei, Mehdi (Supervisor) ; Ghasemi, Shahnaz (Co-Supervisor)
    Biological layers are one of the main problems related to water transfer with pipe lines which are formed through time in the inner surface of the pipes by the water nutrients. Hence, the inner surfaces in the pipe lines and water refineries should be made in order not to let these biological layers to be made. The reason is that when the biofilm is formed on these surfaces, the traversing water is polluted. Dredging of these pipes is not only necessary in most of the countries in the world and needs huge amounts of water but is also very complex and expensive.In this research, nanomaterials, namely ZnO, T〖iO〗_2،S〖iO〗_2 have been used to cover the surface of concrete and steel pipes (The... 

    The externality from communal metering of residential water: the case of Tehran

    , Article Water Resources and Economics ; Volume 23 , July , 2018 , Pages 53-58 ; 22124284 (ISSN) Vesal, M ; Rahmati, M. H ; Taheri Hosseinabadi, N ; Sharif University of Technology
    Elsevier B.V  2018
    Many countries use a single water meter for multiple units within a building. This creates a cost externality where the cost of water consumed is spread over all units. Using administrative data from Tehran Water and Wastewater Co. for 2013 and 2014, we find an increase in the number of units on a communal meter on average increases per unit use by 0.4%. Estimation at different levels of units reveals that almost all communal meters have higher per unit water use. The results suggest that removing this externality could save 2.7% water consumption in our sample. © 2018 Elsevier B.V  

    Synthesis of β-hydroxy dithiocarbamate derivatives via regioselective addition of dithiocarbamate anion to epoxide in water

    , Article Canadian Journal of Chemistry ; 2006, 84, 1515-1519 Ziyaei-Halimjani, A. (Azim) ; Saidi, M. R ; Sharif University of Technology
    The reactions of different dithiocarbamate anions with epoxides were investigated in water. With this method, β-hydroxy dithiocarbamate derivatives were synthesized in high yields. The reaction was also carried out in DMF in the presence of lithium perchlorate with a simple work-up procedure, and the results are compared