Investigation of Electron Transport and Scattering Effect of Dye Sensitized Solar Cells by the Using Titania Nano Particles and Perovskite Structures ( ATiO3)

, M.Sc. Thesis Sharif University of Technology Ayneband, Samaneh (Author) ; Mohammadi, Mohammad Reza (Supervisor)

Abstract

Morphology, microstructure, phase composition and arrangement modes of the photoanode electrode are the most important parameters which affect the photovoltaic properties of dye-sentisized solar cells (DSSCs). In most DSSCs the scattering layer has been used to improve their efficiency. In addition, there are different techniques to improve the electron transport using different morphologies of titania such as one-dimensional nanostructures. In this research, the effect of peroskite structures on electron transport and scattering effect is investigated. Using sol-gel process, the compositions will be produced which have special morphology and appropriate band gap in spite of pure titania....

Improvement of nanosilica effects on the performance of mechanically processed styrene-butadiene rubber by rational hybridization with nanodiamond

, Article Diamond and Related Materials ; Volume 130 , 2022 ; 09259635 (ISSN) Mohammadi, A ; Shojaei, A ; Khasraghi, Samaneh Salkhi ; Sharif University of Technology

Elsevier Ltd 2022

Abstract

Hybrid nanoparticle comprising of nanosilica (NS) and nanodiamond (ND), denoted by ND@NS, was synthesized by a two-step chemistry route and then incorporated into styrene-butadiene rubber (SBR) at low concentrations up to 5 phr by a two-roll mill. Physical hybrids of NS and ND, i.e., ND&NS, with a weight ratio similar to chemical hybrid (80:20 for NS:ND), were also incorporated into SBR. Field emission scanning electron microscopy observations revealed very fine dispersion of nanoparticles in the case of physical hybrids (ND&NS). In contrast, agglomerations and aggregation of nanoparticles were evidenced for ND@NS. Tensile and dynamic mechanical analyses exhibited a higher reinforcing effect...

An Investigation on the Role of Silica Hybrid Nanoparticles on the Properties of Styrene Butadiene Rubber (SBR)

, M.Sc. Thesis Sharif University of Technology Mohammadi, Ali (Author) ; Shojaei, Akbar (Supervisor) ; Salkhi Khasraghi, Samaneh (Co-Supervisor)

Abstract

Hybrid nanoparticle comprising of nanosilica (NS) and nanodiamond (ND), as denoted by ND@NS, was synthesized by a two-step chemistry route and then incorporated into styrene-butadiene rubber (SBR) at low concentrations up to 5 phr by a two-roll mill. Physical hybrids of NS and ND, i.e., ND&NS, with a weight ratio similar to chemical hybrid (80:20 for NS:ND), were also incorporated into SBR. Field emission scanning electron microscopy observations revealed very fine dispersion of nanoparticles in the case of physical hybrids (ND&NS); whereas, agglomerations and aggregation of nanoparticles were evidenced for ND@NS. Tensile and dynamic mechanical analyses exhibited a higher reinforcing effect...

Synthesis and Investigation of Properties of Biocompatible Polyurethane Acrylate Based Nanocomposites/Cellulose Nanocrystals

, M.Sc. Thesis Sharif University of Technology Beik Mohammadi, Mahbubeh (Author) ; Shojaei, Akbar (Supervisor) ; Salkhi, Samaneh (Co-Supervisor)

Abstract

Bio-based shape memory polymers with fast-response have high potential for use in medical applications. In this study, biocompatible and biodegradable nanocomposites based on shape memory polyurethane acrylates (SMPUA)/cellulose nanocrystals (CNC), were synthesized by in-situ polymerization. CNC is a natural and renewable nanoparticle that has been considered for medical applications due to its excellent mechanical and biological properties and surface chemistry. At the first phase of this study, in order to synthesize UV-curable shape memory polyurethane acrylate, polycaprolactone diol (PCL-Diol), hexamethylene diisocyanate (HDI) and hydroxyethyl methacrylate (HEMA) were used as an reactive...

Synthesis and Evaluation of Poly(lactic Acid)/Polyurethane Nano-composites based on Cellulose Nano-particles, with Biomedical Applications

, M.Sc. Thesis Sharif University of Technology Mohammadian Ahrabi, Taha (Author) ; Shojaei, Akbar (Supervisor) ; Salkhi Khasraghi, Samaneh (Co-Supervisor)

Abstract

Shape memory polymers have the potential to use in the field of biomedical applications. In this research, polyurethane structures have been synthesized based on the Diol mixtures, consisting of polycaprolactane diol (PCL-diol) and poly (lactic acid) diol (PLA-diol). Aim of reasearch is about evaluating poly (lactic acid) effect in structure of the polyurethane. At the same time, cellulose nanocrystals (CNC) have been added to polymer matrix to improve properties. The synthesis of acrylated polyurethane, included the synthesis of polyurethane acrylate prepolymer. Next, this prepolymer has been cured by adding the reactive diluent and some polyol. The cured systems were investigated, finally,...

Synthesis and Investigation of Metal–Organic Framework (MOF) on Properties of Biocompatible Polyurethane Acrylate

, M.Sc. Thesis Sharif University of Technology Salavati, Ali (Author) ; Shojaei Segherlou, Akbar (Supervisor) ; Salkhi Khasraghi, Samaneh (Co-Supervisor)

Abstract

The objective of this research is to evaluate different morphologies of UiO-66 structures (pristine state and UiO-66 structure chemically supported on graphene oxide (UiO-66@GO)), on the rheology of polyurethane acrylate nanocomposites prior to UV-curing. The synthesized nanoparticles were characterized by FTIR, FESEM, TGA, XRD, and BET analysis. Rheological investigations, including large amplitude oscillatory sweep, small amplitude oscillatory sweep, steady shear flow, and thixotropic analysis were utilized. Moreover, the obtained rheological results were fitted using the Carreau–Yasuda model, the power-law model, and the Herschel–Bulkley model for quantitative interpretations. The results...

Investigation the Rule of Carbon-Based Quantum Dot on Biocompatible Polyurethane Acrylate

, M.Sc. Thesis Sharif University of Technology Fahimifar, Hamid Reza (Author) ; Shojaei, Akbar (Supervisor) ; Salkhi Khasraghi, Samaneh (Supervisor)

Abstract

Biocompatible materials play a fundamental role in the advancement of medical science and provide groundbreaking solutions for tissue engineering and various therapeutic applications. Among these materials, polyurethane acrylate has attracted attention due to its biocompatibility, versatility, and suitability for creating complex medical scaffolds. This research investigates an innovative approach to reinforce polyurethane acrylate by incorporating graphene quantum dots, with the aim of developing advanced scaffolds for tissue engineering. The incorporation of graphene quantum dots is designed to take advantage of their exceptional properties to improve the mechanical strength, thermal...

Production and Quality Control of 225Ac-PSMA and Absorbed Dose Estimation of its in Different Human Organs

, M.Sc. Thesis Sharif University of Technology Rezazadeh Sefideh, Fatemeh (Author) ; Hoseini, Abolfazl (Supervisor) ; Shirvani Arani, Simindokht (Supervisor) ; Zolghadri, Samaneh (Co-Supervisor)

Abstract

Prostate cancer is the second leading cause of cancer-related mortality in men after lung cancer. Prostate-specific membrane antigen (PSMA-617) labeled with Actinium-225 (225Ac) is currently being studied as a potential treatment for metastatic castration-resistant prostate cancer. This study aimed to produce the labeled compound [225Ac]Ac-PSMA-617 for the treatment of prostate cancer and its metastases. The compound was synthesized under optimized labeling conditions, and its radiochemical purity was determined to be over %96 using RTLC chromatography method. The biodistribution of the compound was evaluated in the tissues of healthy male mice, and the injected activity per unit mass of...