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    Pathology of Conditions of Science in Iran

    , M.Sc. Thesis Sharif University of Technology Kakavandi, Alireza (Author) ; Golshani, Mehdi (Supervisor)
    Abstract
    The purpose of this study is to investigate the causes and reasons of the decline of Iran. The beginnings of decline can be traced to factors such as determinism, esotericism, fundamentalism, the absence of skilled men, as well as the lack of a stable legal system and the emigration of Iranians to foreign countries. Lack of attention and lack of thought about the causes of the decline of Iranian civilization is the main problem of Iran's backwardness. On the other hand, this is the main reason for the growth of Western civilizations. Westerners have made good use of this feature and provided the means for their civilization to flourish. The lack of the concept of decline in a culture does... 

    Encapsulation of spinel CuCo2O4 hollow sphere in V2O5-decorated graphitic carbon nitride as high-efficiency double Z-type nanocomposite for levofloxacin photodegradation

    , Article Journal of Hazardous Materials ; Volume 423 , 2022 ; 03043894 (ISSN) Hasanvandian, F ; Shokri, A ; Moradi, M ; Kakavandi, B ; Rahman Setayesh, S ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    In this study, spinel CuCo2O4 (CCO) with a hierarchical hollow sphere morphology was encapsulated in V2O5-decorated ultra-wrinkled graphitic carbon-nitride (VO-UCN) for the first time via a facile glycerol-assisted solvothermal method in the interest of developing a novel high-efficiency double Z-type nano-photocatalyst (denoted as VO-UCN@CCO). The remarkable physicochemical features of the as-prepared nano-photocatalysts were verified using diverse characterization techniques including TGA, XRD, FT-IR, FE-SEM, TEM, BET, UV–vis DRS, PL, EIS, and transient photocurrent techniques. Herein, VO-UCN@CCO nanocomposite was employed for the photodisintegration of levofloxacin (LVOF) antibiotic under... 

    New high-entropy transition-metal sulfide nanoparticles for electrochemical oxygen evolution reaction

    , Article Electrochimica Acta ; 2022 , Volume 436 ; 00134686 (ISSN) Moradi, M ; Hasanvandian, F ; Bahadoran, A ; Shokri, A ; Zerangnasrabad, S ; Kakavandi, B ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Developing extremely efficient electrocatalysts for oxygen evolution reactions (OER) is a decisive step toward the progression of rechargeable metal-oxygen batteries, CO2 reduction, and water-splitting. Nanoporous high-entropy transition-metal sulfides (np-HETMS) represent a new generation of promising OER catalysts by virtue of their exceptional catalytic activity. However, their synthesis maintains to be a challenge by reason of the thermodynamic immiscibility of the constituting multi-principal metallic elements in the sulfide structure. Herein, for the first time, the np-HETMS ((CoFeNiMnCu)S2) nanoparticles with pyrite-phase was synthesized via a facile and easy adaptable... 

    Improved catalytic performance of ZnO via coupling with CoFe2O4 and carbon nanotubes: A new, photocatalysis-mediated peroxymonosulfate activation system, applied towards Cefixime degradation

    , Article Journal of Environmental Management ; Volume 329 , 2023 ; 03014797 (ISSN) Tian, N ; Giannakis, S ; Akbarzadeh, L ; Hasanvandian, F ; Dehghanifard, E ; Kakavandi, B ; Sharif University of Technology
    Academic Press  2023
    Abstract
    In this study, a ternary ZnO@spinel cobalt ferrite@carbon nanotube magnetic photocatalyst (ZSCF@CNT) was successfully synthesized and used to activate peroxymonosulfate (PMS) for Cefixime (CFX) antibiotic degradation under UVC irradiation. The morphology, optical, structural, and physicochemical properties of ZSCF@CNT were characterized and analyzed by XPS, XRD, FESEM-EDX, TEM, BET, VSM, UV–vis DRS and PL analysis. The results indicated that the ternary ZSCF@CNT photocatalyst exhibited superior catalytic activity on CFX elimination than that of individual components and binary composite catalysts, in which CFX with was rapidly removed under UVC irradiation and PMS. The effect of operational... 

    CuO and ZnO co-anchored on g-C3N4 nanosheets as an affordable double Z-scheme nanocomposite for photocatalytic decontamination of amoxicillin

    , Article Applied Catalysis B: Environmental ; Volume 285 , 2021 ; 09263373 (ISSN) Moradi, M ; Hasanvandian, F ; Isari, A. A ; Hayati, F ; Kakavandi, B ; Setayesh, S. R ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    In this study, both CuO nanoparticles and ZnO nanorods were anchored on thermally-exfoliated g-C3N4 nanosheets (denoted as CZ@T-GCN) via isoelectric point-mediated annealing process as a novel nano-photocatalyst towards degradation of amoxicillin (AMOX). The features of prepared materials were characterized using BET, UV–vis DRS, XRD, FT-IR, XPS, FE-SEM, TEM, EIS and transient photocurrent techniques. These analyses demonstrated the successful formation of heterojunctions between components of CZ@T-GCN nanocomposite, which reflected in significantly increased electron-hole separation and enhanced degradation of AMOX as compared with pure substances. The investigation of influential operative... 

    Effective promotion of g–C3N4 photocatalytic performance via surface oxygen vacancy and coupling with bismuth-based semiconductors towards antibiotics degradation

    , Article Chemosphere ; Volume 287 , 2022 ; 00456535 (ISSN) Hasanvandian, F ; Moradi, M ; Aghaebrahimi Samani, S ; Kakavandi, B ; Rahman Setayesh, S ; Noorisepehr, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    In this research, the potential of bismuth chromate (BCO), a new bismuth-based semiconductor belongs to the family of Bi2XO6 (X = Mo, W, or Cr), was introduced by a novel 1D/2D structure consist of BCO nanobelts and N2-freezed ultra-wrinkled graphitic carbon nitride (N–CN) nanosheets. To enhance intimate contact between BCO and N–CN (BCO/N–CN composite), surface oxygen vacancy (VO) was created as an efficient electron transfer highway using a simple alkaline-treatment-assisted method. Various characterization techniques, including XRD, FT-IR, EPR, FE-SEM, TEM, BET, DRS, PL, EIS, and photocurrent transient analyses were conducted to elucidate the physicochemical aspects of catalysts. The... 

    Enhanced spatially coupling heterojunction assembled from CuCo2S4 yolk-shell hollow sphere capsulated by Bi-modified TiO2 for highly efficient CO2 photoreduction

    , Article Chemical Engineering Journal ; Volume 444 , 2022 ; 13858947 (ISSN) Hasanvandian, F ; Zehtab Salmasi, M ; Moradi, M ; Farshineh Saei, S ; Kakavandi, B ; Rahman Setayesh, S ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    The metal sulfides with highly negative reduction potential and long life-span of photocreated electrons are conducive to being exceptional candidates for CO2 photoreduction, whereas they suffer from self-photo-oxidation (or photocorrosion) that puts the greatest impediment to their practical application. Up to now, the Z-type strategy is stated as a favorable solution to overtake photocorrosion of metal sulfides, while the eligible choice for coupling with these materials is still challenging. TiO2 with more negative onset potential holds favorable inherent peculiarities over other materials, which produces overlapped potential with various ranges of metal sulfides. In this investigation,... 

    Rcci Curvature for Metric-Measure Space via Optimal Transport

    , M.Sc. Thesis Sharif University of Technology Taheri, Abolfazl (Author) ; Bahraini, Alireza (Supervisor) ; Ranjbar Motlagh, Alireza (Co-Advisor)
    Abstract
    One of the important questions in mathematics is generalized. In case of metric spaces, one of the questions is: Can we extend notions of Riemannian geometry to arbitrary metric spaces smoothly? Ricci curvature is one of the most important concepts in differential geometry. Ricci curvature is defined for the Riemannian manifold and has many applications in mathematics and physics like Einstein’s equation in relativity theory. There is a good notion for a metric space having “sectional curvature bounded below by K” or “sectional curvature bounded above by K”, due to Alexandrov. Can we define the concept of Ricci curvature in metric space? A motivation for this question comes from Gromov’s... 

    Intensified photodegradation of nitrobenzene using ZnO-anchored spinel cobalt ferrite: Environmental application, mechanism, and degradation pathway

    , Article Journal of Water Process Engineering ; Volume 49 , 2022 ; 22147144 (ISSN) Ahmadi, M ; Moslemzadeh, M ; Naderi, A ; Zehtab Salmasi, M ; Harati, M ; Rezaei Kalantary, R ; Kakavandi, B ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Aromatic and cyclic organic compounds such as nitrobenzene (NB) are widely used in various industries and are present in their wastewater. In addition, the photocatalytic process has received considerable attention due to its lower chemical consumption and more efficient degradation of refractory pollutants. In this study, a CoFe2O4-ZnO (CFZ) composite was prepared and evaluated its efficiency in the degradation of NB from aqueous solution under UV light. The optical, structural, and physicochemical properties of catalysts were characterized using PL, UV–vis DRS, XRD, TEM, FESEM-EDS, and VSM techniques and then discussed in detail. It was found that not only does the use of CF facilitate the... 

    , M.Sc. Thesis Sharif University of Technology (Author) ; Khaloo, Alireza (Supervisor)
    Abstract
    Seismic design codes reduce loads by using response modification factor. Because of the reserved strength in structural elements and capacity of structure to dissipate energy, structures can be designed for lower seismic loads. This factor has modified over time. In this thesis, the effect of the reduction in behavior factor on the response of two kinds of reinforced concrete systems were evaluated. Moment resisting frames and dual systems with different heights and regularity in plan, heve been design according to the behavior factor which is recommended in the 3rd edition of the Iranian codes of practice for seismic resistance design of buildings (Standard No. 2800). Drift and... 

    Prediction of Financial Markets Using Combination of Artificial Intelligence and Technical Analysis

    , M.Sc. Thesis Sharif University of Technology (Author) ; Haji, Alireza (Supervisor)
    Abstract
    Generally, nowadays, machine learning methods are used in many different areas for their superiority over other methods of prediction. Although being a tough task, stock market prediction with machine learning approaches is being spread due to satisfying results published ever yday. Machine learning methods usually use varied kinds of data ,including structured data such as market data, technical indicators and some fundamental data as well as unstructured one entailing text and graph data in order to enhance their predictability capacity. In this thesis we aimed to find out more about the importance and the contribution of structured data in prediction and we tried to attain a framework... 

    Peroxymonosulfate assisted pesticide breakdown: unveiling the potential of a novel S-scheme ZnO@CoFe2O4 photo-catalyst, anchored on activated carbon

    , Article Environmental Pollution ; Volume 334 , 2023 ; 02697491 (ISSN) Tian, N ; Madani, Z ; Giannakis, S ; Isari, A. A ; Arjmand, M ; Hasanvandian, F ; Noorisepehr, M ; Kakavandi, B ; Sharif University of Technology
    Elsevier Ltd  2023
    Abstract
    A ternary hetero-junction was prepared by anchoring ZnO@CoFe2O4 (ZCF) on activated carbon (AC) and employed as a UV-assisted peroxymonosulfate (PMS) activator to boost the degradation of diazinon (DZN) pesticide. The structure, morphology, and optical properties of the ZCFAC hetero-junction were characterized through a series of techniques. The highest degradation efficiency of DZN (100% in 90 min) was achieved by the PMS-mediated ZCFAC/UV system, superior to other single or binary catalytic systems due to the strong synergistic effect between ZCFAC, PMS, and UV. The operating reaction conditions, synergistic effects, and the possible pathways of DZN degradation were investigated and... 

    , M.Sc. Thesis Sharif University of Technology (Author) ; Hajji, Alireza (Supervisor)
    Abstract
    This thesis presents an inventory control system which is based on Meta-heuristic Algorithms.In this thesis we will optimize the input values of our tree-echelon inventory model (keeping costs,stock worth,reorder costs,...) with these Algorithms. The presented method is able to determine the optimal stock level, costs of system and number of shipments in the system. The method is basically a decision support system (DES) and it is able to provide the order scheduling parameters of goods at operational level. The aim of the current research is to demonstrate that a Meta-heuristic algorithmis capable of solving complex inventory problems and with future improvements it is able to achieve... 

    Spinel cobalt ferrite-based porous activated carbon in conjunction with UV light irradiation for boosting peroxymonosulfate oxidation of bisphenol A

    , Article Journal of Environmental Management ; Volume 342 , 2023 ; 03014797 (ISSN) Kakavandi, B ; Zehtab Salmasi, M ; Ahmadi, M ; Naderi, A ; Roccaro, P ; Bedia, J ; Hasham Firooz, M ; Rezaei Kalantary, R ; Sharif University of Technology
    Academic Press  2023
    Abstract
    Developing heterogeneous catalysts with high performance for peroxymonosulfate (PMS) activation to decontaminate organic pollutants from wastewater is of prominent importance. In this study, spinel cobalt ferrite (CoFe2O4) materials were coated on the surface of powdered activated carbon (CoFe2O4@PAC) via the facile co-precipitation method. The high specific surface area of PAC was beneficial for the adsorption of both bisphenol A (BP-A) and PMS molecules. The CoFe2O4@PAC-mediated PMS activation process under UV light could effectively eliminate 99.4% of the BP-A within 60 min of reaction. A significant synergy effect was attained between CoFe2O4 and PAC towards PMS activation and subsequent... 

    The Ricci Flow with Applications to the Poincare and Calabi Conjectures

    , M.Sc. Thesis Sharif University of Technology Safdari, Mohammad (Author) ; Bahreini, Alireza (Supervisor)
    Abstract
    Poincare conjecture is one of the rst eorts for classifying 3-manifolds that was stated in the begining of 20th century. Eorts for proving this conjecture continued for about 100 years and nally Perelman has solved it in 2003. He has used Ricci ow which has been invented by Richard Hamilton in the early 80's. In this thesis rst we will introduce Ricci ow and will state the results before Perelman such as short time and long time existence of solution. Then we will mention some applications of Ricci ow and will state an explanation of the proof of uniformization and Calabi conjecture by Ricci ow. After that we start the main part of the thesis. In this part we will montion one of the... 

    Feasibility And Study(CNG Cylinder Production Plant)

    , M.Sc. Thesis Sharif University of Technology Mousavi, Mohammad (Author) ; Haji, Alireza (Supervisor)
    Abstract
    Nowadays best using of fossil fuels sources of the country (and) importance of comparison against lack of capacity in petrol production make determined the programmers and the directors to foresee and design expanded programs of the goals, to use natural gas for car fuels. To reach fulfillment of these programs, the confirmed needs of the natural gas cylinders are improved and make it essential to invest on producing compressive natural gas cylinders. In this way economical and technical change researches has been done in order to construct on department to produce 200,000 compressive natural gas cylinders in a year during two sets.(shifts) According to the results of technical researches... 

    Synthesis, Characterization and Field Emission Study of Molybdenum Oxide (MoOx)Nanostructures

    , M.Sc. Thesis Sharif University of Technology Khademi, Ali (Author) ; Moshfegh, Alireza (Supervisor)
    Abstract
    Different molybdenum oxide nano/micro structure thin films were synthesized by thermal evaporation method under various growth conditions such as deposition time, temperature and evaporation source-substrate distance. Molybdenum oxide nanostructures grown on Si(100) such as nanowalls, nanostars and nanowires were characterized with scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HRTEM). Shape and type of nanostructures were determined with SEM, AFM and HRTEM analysis. XPS analysis showed that the synthesized nanostructures contained Mo6+, Mo5+, Mo4+ and... 

    Identification and Abnormal Condition Detection of a Cement Rotary Kiln

    , M.Sc. Thesis Sharif University of Technology Sadeghian, Masoud (Author) ; Fatehi, Alireza (Supervisor)
    Abstract
    One of the most important parts of a cement factory is the cement rotary kiln which plays a key role in quality and quantity of produced cement. In this part, the physical exertion and bilateral movement of air and materials, together with chemical reactions take place. Thus, this system has immensely complex and nonlinear dynamic equations. These equations have not worked out yet. Only in exceptional case; however, a large number of the involved parameters were crossed out and an approximation model was presented instead. This issue caused many problems for designing a cement rotary kiln controller. In this thesis, we employed a nonlinear system identification method for identification,... 

    Entanglement and Decoherence in Optomechanical Systems Coupled through Photothermal Effects

    , Ph.D. Dissertation Sharif University of Technology Abdi, Mehdi (Author) ; Bahrampour, Alireza (Supervisor)
    Abstract
    Optomechanical systems have attracted considerable attention in the last decade. Such a raising prominence is mainly due to its capability in providing new insight into the quantum behavior of macroscopic objects and exploring the interface between quantum and classical mechanics. Alongside this fundamental quest, cavity optomechanics has many other benefits, ranging from very precise measurements on forces and positions to quantum information processing. In this thesis, we investigate quantum properties of such systems. Particularly, we study cooling of the mechanical resonator toward its ground state and the entanglement between this mechanical resonator and the cavity field. Cooling the... 

    Improvement in Reinforced Concrete Beam-Column Connections Behaviour using FRP Sheets

    , M.Sc. Thesis Sharif University of Technology Rokrokian, Ali (Author) ; Khaloo, Alireza (Supervisor)
    Abstract
    Performance of reinforced concrete frames is highly dependent on detailing of the joint connections between its members, such as beams and columns. To have a good structural behavior, joints must show ductile behavior and designed based on the philosophy of strong column-weak beam. In the case of sever lacking ductility, strength or even rigidity of the connections, or having a weak column-strong beam, in the existing structures, there is a need for seismic upgrading of the connection. There are several ways for seismic upgrading of this type of connections.In the last decade Fiber Reinforced Polymer (FRP) widely has been used to strengthening the reinforced concrete (RC) members. Most of...