Accession Number : AD1051266


Title :   Nanoscale Magnetism in Next Generation Magnetic Nanoparticles


Descriptive Note : Technical Report,30 Sep 2014,29 Sep 2017


Corporate Author : UNIVERSITY COLLEGE LONDON London United Kingdom


Personal Author(s) : Thanh,Nguyen ; Phuc, Xuan ; Sridhar,Srinivas


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/1051266.pdf


Report Date : 17 Mar 2018


Pagination or Media Count : 26


Abstract : Magnetic nanoparticles (MNPs) are key components of a variety of sensors for diverse applications in electronics and biotechnologies. Nanoparticle properties are critically affected both by nanoscale size as well as surface interactions with the environment. These interactions among the key fundamental properties such as magnetic moment and dynamic response that are required for use in applications. This was collaborative project between groups at Northeastern University (USA), University College London-UCL (UK) and Institute of Materials Science (Vietnam Academy of Science and Technology-VAST) to synthesis and understand the fundamental aspects of magnetism at the nanometer length scale in confined geometries in nanoparticles. At Northeastern University, the dynamic relaxation of superparamagnetic iron oxide nanoparticles (SPIONs) in aqueous media was studied. Using the MRI facilities at Northeastern University, MNPs from collaborators UCL and VAST, as well as dextran coated SPIONs were studied. From the measured T1 and T2 relaxation times, a new method called Quantitative Ultra-Short Time-to-Echo Contrast Enhanced (QUTE-CE) Magnetic Resonance Imaging (MRI) was developed. The method was tested in vivo and demonstrated to yield positive contrast angiograms with high clarity and definition, and enabled quantitative MRI in biological samples. At UCL, the work included (i) fabricating multi-element magnetic systems, and (ii) controlling interactions by surface modification using organic compounds. The project involves systematic matter property studies by fabrication of novel organically modified coating of MNPs, physical characterization at both macroscopic level such as magnetic moments and AC susceptibility as well as microscopic one. The results provided fundamental insights into the nature of nanoscale magnetism relevant to a variety of nanomagnetic applications.


Descriptors :   Nanoparticles , Nanotechnology , materials processing , chemical vapor deposition , biosensors , raman spectroscopy , metallic nanoparticles , field effect transistors , graphene , glass transition temperature , fullerenes


Distribution Statement : APPROVED FOR PUBLIC RELEASE