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Photodynamic Therapy by Er And Yb Doped TiO2 Upconversion Nanoparticles
, M.Sc. Thesis Sharif University of Technology ; Maddah Hosseini, Hamid Reza (Supervisor)
Abstract
Photodynamic therapy that has been developed over last century, now has become more widely used medical tool for the treatment of various diseases such as cancer. This technique involves delivery of photosensitizing drugs, irradiation of light and motivation of drugs. The limitation of light penetration in body tissue, may resolve by application of upconversion nanoparticles. Upconverting nanoparticles could help treatment of cancer tumors in deep or critical points of body by converting high penetrating Near-Infrared emissions to higher energy visible emissions. In the present work, rare earth elements doped TiO2 nanoparticles are synthesized. The photodynamic properties of rare earth...
Synthesis of Titania Coated Upconversion Nanoparticles with the Capability of Being Utilized in Photodynamic Therapy Under the Near-Infrared Radiation
, Ph.D. Dissertation Sharif University of Technology ; Madaaah Hosseini, Hamid Reza (Supervisor) ; Soleimani, Masoud (Supervisor) ; Mohajerani, Ezeddin (Co-Supervisor)
Abstract
Development of novel photosensitizers and photocatalysts with near-infrared (NIR) light activity and efficient sunlight harvesting is of great importance in photodynamic therapy and environmental remediation. In this work, very small (20 nm) upconverter SrF2:Yb,Tm@CaF2:Yb@Fluorine-doped TiO2 heteronanoparticles (denoted as UCNPs@TiO2) with strong UV-blue emission and wide-spectrum photocatalytic activity were synthesized via a facile three-step hydrothermal method, for the first time. The SrF2: Yb,Tm upconverter nanoparticles were produced as the light-emitting core, epitaxially-grown CaF2 : Yb as the middle shell to enhance the Upconversion luminescence efficiency and TiO2 as the...
Enhanced TiO2broadband photocatalytic activity based on very small upconversion nanosystems
, Article Journal of Physical Chemistry C ; Volume 125, Issue 25 , 2021 , Pages 13788-13801 ; 19327447 (ISSN) ; Madaah Hosseini, H. R ; Mohajerani, E ; Pedroni, M ; Taheri Ghahrizjani, R ; Sharif University of Technology
American Chemical Society
2021
Abstract
Efficient sunlight harvesting is of great significance for environmental remediation through photocatalysis. Herein, very small (20 nm) upconverter SrF2:Yb,Tm@CaF2:Yb@Fluorine-doped TiO2heteronanoparticles (denoted as UCNPs@TiO2) with strong UV-blue emission and broadband photocatalytic performance were prepared via a facile three-step hydrothermal method for the first time. The SrF2:Yb,Tm upconverter nanoparticles (NPs) were produced as the light-emitting core, epitaxially grown CaF2:Yb as the middle shell to enhance the upconversion luminescence output and TiO2as the photocatalyst outermost layer. Superior photocatalytic functioning of UCNPs@TiO2was affirmed through methylene blue (MB)...
Influence of Y3+, Yb3+, Gd3+ cations on structural and electromagnetic properties of CuFe2O4 nanoferrites prepared via one step sol-gel method
, Article Journal of Rare Earths ; Volume 39, Issue 10 , 2021 , Pages 1224-1231 ; 10020721 (ISSN) ; Akhtar, M. N ; Yousaf, M ; Batoo, K. M ; Aldossary, O. M ; Khan, S. N ; Sharif University of Technology
Editorial Office of Chinese Rare Earths
2021
Abstract
Rare earths (REs) play a key role in distorting spinel structure by creating some defects at the lattice sites and make them suitable for magnetodielectric applications. In the present study, the nanoferrites of CuRE0.02Fe1.98O4, where REs = Y3+, Yb3+, Gd3+, were prepared using one step sol–gel method. The prepared samples are copper ferrite (CFO), yttrium doped copper ferrite (Y-CFO), ytterbium doped copper ferrite (Yb-CFO) and gadolinium doped copper ferrite (Gd-CFO), respectively. The single-phase structure of all the REs doped nanoferrites was determined by X-ray diffraction (XRD) analysis. The porosity, agglomerations and grain size of the REs doped copper ferrite were examined using...
Geochemical characteristics of rare earth elements in different types of soil: a chemometric approach
, Article Chemosphere ; Volume 184 , 2017 , Pages 673-678 ; 00456535 (ISSN) ; Behkami, S ; Yusoff, I ; Md Zain, S. B ; Bakar, N. K. A ; Bakar, A. F. A ; Alias, Y ; Sharif University of Technology
Abstract
Rare earth elements (REEs) are becoming significant due to their huge applications in many industries, large-scale mining and refining activities. Increasing usage of such metals pose negative environmental impacts. In this research ICP-MS has been used to analyze soil samples collected from former ex-mining areas in the depths of 0–20 cm, 21–40 cm, and 41–60 cm of residential, mining, natural, and industrial areas of Perak. Principal component analysis (PCA) revealed that soil samples taken from different mining, industrial, residential, and natural areas are separated into four clusters. It was observed that REEs were abundant in most of the samples from mining areas. Concentration of the...