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    Application of a dual functional luminescent layer to enhance the light harvesting efficiency of dye sensitized solar cell

    , Article Materials Letters ; 2016 ; 0167577X (ISSN) Hosseini, Z ; Taghavinia, N ; Diau, E. W. G
    Elsevier B.V  2016
    A luminescent coating of CaAlSiN3:Eu2+ particles applied on photoanode (TiO2) layer of SQ1 sensitized solar cell by doctor blading the paste of phosphor particles. The luminescent layer acted as a dual functional layer and enhanced the short circuit current density (JSC) by 64% via both scattering effect and downshifting of the photons in 400-600nm spectral range to photons in 600-800nm spectral range. Considerable relative enhancement in incident photon to current conversion efficiency (IPCE) up to 350% in 400-600nm spectral range proves the down shifting effect as the dominant factor for the improved performance of dye sensitized solar cell (DSSC). © 2016 Elsevier B.V  

    Probabilistic unit commitment with wind farms considerations

    , Article 2007 Large Engineering Systems Conference on Power Engineering, LESCOPE'07, Montreal, QC, 10 October 2007 through 12 October 2007 ; January , 2007 , Pages 73-77 ; 9781424415830 (ISBN) Hosseini, H ; Abbasi, E ; Sharif University of Technology
    This paper proposes a method for unit commitment in restructured power systems with high penetration of wind farms. As wind is an intermittent source of energy and can not be predicted with high accuracy, reliability of wind farms compare to conventional power plants is lower. By increasing penetration of wind farms in generation system, reliability of power system will decrease. Therefore, reliability constraint should be added to unit commitment (UC) formulation. On the other hand, wind is a green source of energy; additionally environmental crisis is very important issue in the 21st century. By adding emission constraint to UC, wind energy will be valued. Both reliability and emission... 

    Experimental and numerical fatigue life study of cracked AL plates reinforced by glass/epoxy composite patches in different stress ratios

    , Article Mechanics Based Design of Structures and Machines ; Volume 49, Issue 6 , 2021 , Pages 894-910 ; 15397734 (ISSN) Hosseini, K ; Safarabadi, M ; Ganjiani, M ; Mohammadi, E ; Hosseini, A ; Sharif University of Technology
    Bellwether Publishing, Ltd  2021
    In this study, the fatigue behavior of composite reinforced cracked aluminum 1050 plates is investigated experimentally and numerically. The tests are conducted in four different stress ratios between 0 and 1. At first step, plates with similar cracks and geometries have been prepared. Then the glass/epoxy patches have been attached to the cracked plates using Araldite 2015 adhesive. Fatigue load has been applied to three cases of samples including non-patch, one-side patch and two-side patch, where in all stress ratios the maximum force is considered constant. A three-dimensional finite element analysis is developed in ABAQUS. A good correlation between finite element results and the... 

    Analysis of lattice temperature effects on a GaInP/6H-SiC strained quantum-well lasers

    , Article Asian Journal of Chemistry ; Volume 25, Issue 9 , Oct , 2013 , Pages 4715-4717 ; 09707077 (ISSN) Marjani, S ; Faez, R ; Hosseini, S. E ; Sharif University of Technology
    In this paper, simulative study on the effects of lattice temperature on a GaInP/6H-SiC strained quantum-well (QW) laser's device is presented. Loss mechanisms are severe in the edge-emitting lasers. As a consequence, the wall-plug efficiency is sensitive to changes in temperature. The lasers used in this work were separate-confinement quantum-well lasers with a single strained GaInP, located in a latticematched waveguide core and cladding region of 6H-SiC. This paper provides the key results of the wall-plug efficiency upon the lattice temperature  

    A hierarchical sub-chromosome genetic algorithm (Hsc-ga) to optimize power consumption and data communications reliability in wireless sensor networks

    , Article Wireless Personal Communications ; Volume 80, Issue 4 , 2015 , Pages 1579-1605 ; 09296212 (ISSN) Hosseini, E. S ; Esmaeelzadeh, V ; Eslami, M ; Sharif University of Technology
    High reliability and low power consumption are among the major requirements in design of wireless sensor networks (WSNs). In this paper, a multi-objective problem is formulated as a Joint Power consumption and data Reliability (JPR) optimization problem. For this purpose, a connected dominating set (CDS)-based topology control approach is proposed. Our objective is to self-organize the network with minimum interference and power consumption. We consider the power changes into a topology with minimum CDS infrastructure subject to connectivity constraints. Since this problem is NP-hard, it cannot be dealt with using polynomial-time exact algorithms. Therefore, we first present a genetic... 

    Advanced on-site glucose sensing platform based on a new architecture of free-standing hollow Cu(OH)2 nanotubes decorated with CoNi-LDH nanosheets on graphite screen-printed electrode

    , Article Nanoscale ; Volume 11, Issue 26 , 2019 , Pages 12655-12671 ; 20403364 (ISSN) Shahrokhian, S ; Khaki Sanati, E ; Hosseini, H ; Sharif University of Technology
    Royal Society of Chemistry  2019
    The planned design of nanocomposites combined with manageable production processes, which can offer controllability over the nanomaterial structure, promises the practical applications of functional nanomaterials. Hollow core-shell nanostructure architectures represent an emerging category of advanced functional nanomaterials, whose benefits derived from their notable properties may be hampered by complicated construction processes, especially in the sensing domain. In this regard, we designed a highly porous three-dimensional array of hierarchical hetero Cu(OH)2@CoNi-LDH core-shell nanotubes via a quick, very simple, green, and highly controllable three-step in situ method; they were... 

    Direct growth of metal-organic frameworks thin film arrays on glassy carbon electrode based on rapid conversion step mediated by copper clusters and hydroxide nanotubes for fabrication of a high performance non-enzymatic glucose sensing platform

    , Article Biosensors and Bioelectronics ; Volume 112 , 2018 , Pages 100-107 ; 09565663 (ISSN) Shahrokhian, S ; Khaki Sanati, E ; Hosseini, H ; Sharif University of Technology
    Elsevier Ltd  2018
    The direct growth of self-supported metal-organic frameworks (MOFs) thin film can be considered as an effective strategy for fabrication of the advanced modified electrodes in sensors and biosensor applications. However, most of the fabricated MOFs-based sensors suffer from some drawbacks such as time consuming for synthesis of MOF and electrode making, need of a binder or an additive layer, need of expensive equipment and use of hazardous solvents. Here, a novel free-standing MOFs-based modified electrode was fabricated by the rapid direct growth of MOFs on the surface of the glassy carbon electrode (GCE). In this method, direct growth of MOFs was occurred by the formation of vertically... 

    On the evolution of flow stress during constrained groove pressing of pure copper sheet

    , Article Computational Materials Science ; Volume 45, Issue 4 , 2009 , Pages 855-859 ; 09270256 (ISSN) Hosseini, E ; Kazeminezhad, M ; Mani, A ; Rafizadeh, E ; Sharif University of Technology
    Using a mechanical model and dislocation density based model, the evolutions of dislocation density and flow stress of pure copper during constrained groove pressing (CGP) process are investigated. In this regard, the strain and strain rate are achieved from the mechanical model and then input into the dislocation model. To verify the predicted flow stress, the process of constrained groove pressing is performed on the sheets of pure copper from one to three passes. The predicted flow stresses are compared with the experimental data and a good agreement is observed. Also, it is found that during the straining of the copper sheet in CGP process, the dislocation density and strength dropping... 

    Luminescent Spectral Conversion to Improve the Performance of Dye-Sensitized Solar Cells

    , Article ChemPhysChem ; Volume 18, Issue 23 , 2017 , Pages 3292-3308 ; 14394235 (ISSN) Hosseini, Z ; Taghavinia, N ; Wei Guang Diau, E ; Sharif University of Technology
    Relative to the broadband solar spectrum, a narrow range of spectral absorption of photovoltaic (PV) devices is considered an important determinant that the efficiency of light harvesting of these devices is less than unity. Having the narrowest spectral response to solar radiation among all PV devices, dye-sensitized solar cells (DSSCs) suffer severely from this loss. Luminescent spectral conversion provides a mechanism to manipulate and to adapt the incident solar spectrum by converting, through photoluminescence, the energies of solar photons into those that are more effectively captured by a PV device. This mechanism is particularly helpful for DSSCs because there is much flexibility in... 

    Optimization of head CT protocol to reduce the absorbed dose in eye lenses and thyroid: A phantom study

    , Article Iranian Journal of Medical Physics ; Volume 16, Issue 1 , 2019 , Pages 64-74 ; 1735160X (ISSN) Kalhor, P ; Changizi, V ; Hosseini, A ; Jazayeri, E ; Sharif University of Technology
    Mashhad University of Medical Sciences  2019
    Introduction: Utilization of computed tomography (CT) scans is increasing annually. This study aimed to reduce the absorbed dose of sensitive organs in the head (eye lenses and thyroid) and to assess changes in resultant images quality in head scans when the radiation dose is decreased. Material and Methods: An anthropomorphic phantom was examined with head protocols in both helical and sectional modes using two 16-slice CT scanners. The entrance surface dose of eye lenses and thyroid was measured with standard protocols and after reducing the mAS and kilo-voltage using thermo-luminescence dosimeters (TLDs). Results: In sectional mode with standard protocol, the highest surface dose was 2.3... 

    Application of a dual functional luminescent layer to enhance the light harvesting efficiency of dye sensitized solar cell

    , Article Materials Letters ; Volume 188 , 2017 , Pages 92-94 ; 0167577X (ISSN) Hosseini, Z ; Taghavinia, N ; Diau, E. W. G ; Sharif University of Technology
    Elsevier B.V  2017
    A luminescent coating of CaAlSiN3:Eu2+ particles applied on photoanode (TiO2) layer of SQ1 sensitized solar cell by doctor blading the paste of phosphor particles. The luminescent layer acted as a dual functional layer and enhanced the short circuit current density (JSC) by 64% via both scattering effect and downshifting of the photons in 400–600 nm spectral range to photons in 600–800 nm spectral range. Considerable relative enhancement in incident photon to current conversion efficiency (IPCE) up to 350% in 400–600 nm spectral range proves the down shifting effect as the dominant factor for the improved performance of dye sensitized solar cell (DSSC). © 2016 Elsevier B.V  

    Determination of mechanical properties of FCC nano-beams based on molecular dynamics simulations

    , Article 5th International Symposium on Mechatronics and its Applications, ISMA 2008, Amman, 27 May 2008 through 29 May 2008 ; October , 2008 ; 9781424420346 (ISBN) Nejat Pishkenari, H ; Meghdari, A ; Hosseini, A. E ; Sharif University of Technology
    In this research, we have modeled nano-Beams using molecular dynamics. The scope of our study is FCC metals, therefore an appropriate inter-atomic potential for this kind of materials must be chosen. A multi-body long-range potential proposed by Sutton-Chen, which has been used in many physical investigations of FCC metals is applied in our study. Using conducted simulations, the different mechanical properties of material such as elastic modulus, shear modulus and poison's ratio are calculated. The results show that the elastic properties decrease with increase in nano cantilever size. ©2008 IEEE  

    Ranking locations for hydrogen production using hybrid wind-solar: a case study

    , Article Sustainability (Switzerland) ; Volume 13, Issue 8 , 2021 ; 20711050 (ISSN) Almutairi, K ; Mostafaeipour, A ; Jahanshahi, E ; Jooyandeh, E ; Himri, Y ; Jahangiri, M ; Issakhov, A ; Chowdhury, S ; Hosseini Dehshiri, J ; Hosseini Dehshiri, S ; Techato, K ; Sharif University of Technology
    MDPI  2021
    Observing the growing energy demand of modern societies, many countries have rec-ognized energy security as a looming problem and renewable energies as a solution to this issue. Renewable hydrogen production is an excellent method for the storage and transfer of energy generated by intermittent renewable sources such as wind and solar so that they can be used at a place and time of our choosing. In this study, the suitability of 15 cities in Fars province, Iran, for renewable hydrogen production was investigated and compared by the use of multiple multi-criteria decision-making methods including ARAS, SAW, CODAS, and TOPSIS. The obtained rankings were aggregated by rank averaging, Borda... 

    Mechanical performance of self-compacting concrete reinforced with steel fibers

    , Article Construction and Building Materials ; Volume 51 , 31 January , 2014 , Pages 179-186 ; ISSN: 09500618 Khaloo, A ; Raisi, E. M ; Hosseini, P ; Tahsiri, H ; Sharif University of Technology
    Self-compacting concrete (SCC) is a highly-workable concrete that without any vibration or impact and under its own weight fills the formwork, and it also passes easily through small spaces between rebars. In this paper, the effect of steel fibers on rheological properties, compressive strength, splitting tensile strength, flexural strength, and flexural toughness of SCC specimens, using four different steel fiber volume fractions (0.5%, 1%, 1.5%, and 2%), were investigated. Two mix designs with strengths of 40 MPa (medium strength) and 60 MPa (high strength) were considered. Rheological properties were determined through slump flow time and diameter, L-box, and V-funnel flow time tests.... 

    Assessment of luminescent downshifting layers for the improvement of light-harvesting efficiency in dye-sensitized solar cells

    , Article ChemPhysChem ; Vol. 15, issue. 17 , 2014 , pp. 3791-3799 ; ISSN: 14394235 Hosseini, Z ; Diau, E. W. G ; Mehrany, K ; Taghavinia, N ; Sharif University of Technology
    Luminescence downshifting (LDS) of light can be a practical photon management technique to compensate the narrow absorption band of high-extinction-coefficient dyes in dye-sensitized solar cells (DSSCs). Herein, an optical analysis on the loss mechanisms in a reflective LDS (R-LDS)/DSSC configuration is reported. For squaraine dye (550-700 nm absorption band) and CaAlSiN3:Eu2+ LDS material (550-700 nm emission band), the major loss channels are found to be non-unity luminescence quantum efficiency (QE) and electrolyte absorption. By using an ideal LDS layer (QE=100 %), a less absorbing electrolyte (Co-based), and antireflection coatings, approximately 20% better light harvesting is obtained.... 

    Characterization of three-dimensional reduced graphene oxide/copper oxide heterostructures for hydrogen sulfide gas sensing application

    , Article Journal of Alloys and Compounds ; Volume 740 , 2018 , Pages 1024-1031 ; 09258388 (ISSN) Mirmotallebi, M ; Iraji zad, A ; Hosseini, Z. S ; Jokar, E ; Sharif University of Technology
    Elsevier Ltd  2018
    Three-dimensional reduced graphene oxide (3D-rGO) structures decorated with CuO particles (GCu) are synthesized through a simple and scalable method for detection of hydrogen sulfide (H2S) gas. For characterization and investigation of porous structure various techniques were employed. Decorated 3D structures demonstrated higher sensitivity and selectivity in comparison to pure structure. Optimized structure for sensing was obtained through introducing different amounts of CuO. The GCu heterostructures containing 35 μmol of CuO powder demonstrated reproducible response of about 30% to the concentration of 10 ppm at room temperature, while complete recovery was obtained through heating to 150... 

    Electrokinetic properties of asphaltene colloidal particles: determining the electric charge using micro electrophoresis technique

    , Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 541 , 2018 , Pages 68-77 ; 09277757 (ISSN) Azari, V ; Abolghasemi, E ; Hosseini, A ; Ayatollahi, S ; Dehghani, F ; Sharif University of Technology
    Elsevier B.V  2018
    In this work, the electrokinetic properties of asphaltene particles have been investigated. Micro-electrophoresis method by applying DC electric field, was utilized to different mixtures containing asphaltene to determine its electric charge. It was observed that in the case of using n-heptane and its mixture with toluene (heptol), the asphaltene particles were showed to be positively charged however for toluene itself, they expressed no tendency toward the electrodes. While it is expected that larger asphaltene aggregates carry higher electric charge, the results contradictorily showed that they are mainly governed by gravity rather than electro-static force and that “aggregation” reduces... 

    RSM based engineering of the critical gelation temperature in magneto-thermally responsive nanocarriers

    , Article European Polymer Journal ; Volume 120 , 2019 ; 00143057 (ISSN) Khodaei, A ; Bagheri, R ; Madaah Hosseini, H. R ; Bagherzadeh, E ; Sharif University of Technology
    Elsevier Ltd  2019
    The multistep release of therapeutic agents in the theranostic particulate systems has remained as a challenge in smart drug delivery. In this study, superparamagnetic nanoparticles of Fe3O4 were coated with a blend of F127/F68 grades of pluronic in order to adjust the lower critical solution temperature (LCST) and consequently engineering of the release temperature. Pluronic as a biocompatible thermo-sensitive polymer is frequently used as a self-emulsifying drug delivery system. Magnetite nanoparticles with double layer coating of oleic acid and pluronic F127 have been reported as an on-demand smart carrier for hydrophobic drugs. LCST was examined using differential scanning calorimetry... 

    Lake Urmia restoration success story: A natural trend or a planned remedy?

    , Article Journal of Great Lakes Research ; Volume 47, Issue 4 , 2021 , Pages 955-969 ; 03801330 (ISSN) Nikraftar, Z ; Parizi, E ; Hosseini, S. M ; Ataie Ashtiani, B ; Sharif University of Technology
    International Association of Great Lakes Research  2021
    Lake Urmia is the second-largest hypersaline lake in the world. There has been a drastic water level drop of 7.2 m from 1995 to 2016. Beginning in October 2013, the Lake Urmia Restoration Plan (LURP) launched a 10-year program. An increase in water level and a relative improvement in Lake Urmia condition has been observed since 2017. It is an undecided and controversial issue whether the recent positive trend of Lake Urmia has been due to the LURP activities or it is a natural contribution of climate factors variations. To shed some light on this issue, we examine three other lakes, adjacent to the Lake Urmia basin, with similar rainfall variability to investigate their status during the... 

    Distribution transformer relocation problem: an integer programming solution

    , Article IET Generation, Transmission and Distribution ; Volume 15, Issue 1 , 2021 , Pages 108-120 ; 17518687 (ISSN) Azimi Hosseini, K ; Hajiaghapour Moghimi, M ; Hajipour, E ; Vakilian, M ; Sharif University of Technology
    John Wiley and Sons Inc  2021
    The short-term expansion planning of the private utilities, as well as the emerging technologies such as photovoltaic panels (PVs), plug-in hybrid electric vehicles (PHEVs), cryptocurrency mining, and storage elements spread, make the long-term load estimation of distribution transformers (DTs) noticeably imprecise. In response, the number of overload and underload transformers is growing in recent years. The utilities normally analyse the loading of their DTs annually to determine the DTs, which should be replaced. It is a common practice for utilities to relocate these DTs to reduce the investment needed to purchase new transformers. Therefore, the utility needs a systematic algorithm to...