Manipulation of Magnetism in Iron Oxide Nanoparticle / Batio3 Composites and Low-Dimensional Iron Oxide Nanoparticle Arrays
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Canted Ferrimagnetism and Giant Coercivity in the Non-Stoichiometric
Canted ferrimagnetism and giant coercivity in the non-stoichiometric double perovskite La2Ni1.19Os0.81O6 Hai L. Feng1, Manfred Reehuis2, Peter Adler1, Zhiwei Hu1, Michael Nicklas1, Andreas Hoser2, Shih-Chang Weng3, Claudia Felser1, Martin Jansen1 1Max Planck Institute for Chemical Physics of Solids, Dresden, D-01187, Germany 2Helmholtz-Zentrum Berlin für Materialien und Energie, Berlin, D-14109, Germany 3National Synchrotron Radiation Research Center (NSRRC), Hsinchu, 30076, Taiwan Abstract: The non-stoichiometric double perovskite oxide La2Ni1.19Os0.81O6 was synthesized by solid state reaction and its crystal and magnetic structures were investigated by powder x-ray and neutron diffraction. La2Ni1.19Os0.81O6 crystallizes in the monoclinic double perovskite structure (general formula A2BB’O6) with space group P21/n, where the B site is fully occupied by Ni and the B’ site by 19 % Ni and 81 % Os atoms. Using x-ray absorption spectroscopy an Os4.5+ oxidation state was established, suggesting presence of about 50 % 5+ 3 4+ 4 paramagnetic Os (5d , S = 3/2) and 50 % non-magnetic Os (5d , Jeff = 0) ions at the B’ sites. Magnetization and neutron diffraction measurements on La2Ni1.19Os0.81O6 provide evidence for a ferrimagnetic transition at 125 K. The analysis of the neutron data suggests a canted ferrimagnetic spin structure with collinear Ni2+ spin chains extending along the c axis but a non-collinear spin alignment within the ab plane. The magnetization curve of La2Ni1.19Os0.81O6 features a hysteresis with a very high coercive field, HC = 41 kOe, at T = 5 K, which is explained in terms of large magnetocrystalline anisotropy due to the presence of Os ions together with atomic disorder. -
Iron (III) Oxide Anhydrous
Material Safety Data Sheet Iron (III) Oxide Anhydrous MSDS# 11521 Section 1 - Chemical Product and Company Identification MSDS Name: Iron (III) Oxide Anhydrous Catalog Numbers: I116-3, I116-500 Synonyms: Ferric Oxide Red; Iron (III) Oxide; Iron Sesquioxide; Red Iron Oxide. Fisher Scientific Company Identification: One Reagent Lane Fair Lawn, NJ 07410 For information in the US, call: 201-796-7100 Emergency Number US: 201-796-7100 CHEMTREC Phone Number, US: 800-424-9300 Section 2 - Composition, Information on Ingredients ---------------------------------------- CAS#: 1309-37-1 Chemical Name: Iron (III) Oxide %: 100 EINECS#: 215-168-2 ---------------------------------------- Hazard Symbols: None listed Risk Phrases: None listed Section 3 - Hazards Identification EMERGENCY OVERVIEW Warning! May cause respiratory tract irritation. May cause mechanical eye and skin irritation. Inhalation of fumes may cause metal-fume fever. Causes severe digestive tract irritation with pain, nausea, vomiting and diarrhea. May corrode the digestive tract with hemorrhaging and possible shock. Target Organs: None. Potential Health Effects Eye: Dust may cause mechanical irritation. Skin: Dust may cause mechanical irritation. May cause severe and permanent damage to the digestive tract. May cause liver damage. Causes severe pain, Ingestion: nausea, vomiting, diarrhea, and shock. May cause hemorrhaging of the digestive tract. The toxicological properties of this substance have not been fully investigated. Dust is irritating to the respiratory tract. Inhalation of fumes may cause metal fume fever, which is characterized Inhalation: by flu-like symptoms with metallic taste, fever, chills, cough, weakness, chest pain, muscle pain and increased white blood cell count. Chronic: Chronic inhalation may cause effects similar to those of acute inhalation. -
Magnetism, Magnetic Properties, Magnetochemistry
Magnetism, Magnetic Properties, Magnetochemistry 1 Magnetism All matter is electronic Positive/negative charges - bound by Coulombic forces Result of electric field E between charges, electric dipole Electric and magnetic fields = the electromagnetic interaction (Oersted, Maxwell) Electric field = electric +/ charges, electric dipole Magnetic field ??No source?? No magnetic charges, N-S No magnetic monopole Magnetic field = motion of electric charges (electric current, atomic motions) Magnetic dipole – magnetic moment = i A [A m2] 2 Electromagnetic Fields 3 Magnetism Magnetic field = motion of electric charges • Macro - electric current • Micro - spin + orbital momentum Ampère 1822 Poisson model Magnetic dipole – magnetic (dipole) moment [A m2] i A 4 Ampere model Magnetism Microscopic explanation of source of magnetism = Fundamental quantum magnets Unpaired electrons = spins (Bohr 1913) Atomic building blocks (protons, neutrons and electrons = fermions) possess an intrinsic magnetic moment Relativistic quantum theory (P. Dirac 1928) SPIN (quantum property ~ rotation of charged particles) Spin (½ for all fermions) gives rise to a magnetic moment 5 Atomic Motions of Electric Charges The origins for the magnetic moment of a free atom Motions of Electric Charges: 1) The spins of the electrons S. Unpaired spins give a paramagnetic contribution. Paired spins give a diamagnetic contribution. 2) The orbital angular momentum L of the electrons about the nucleus, degenerate orbitals, paramagnetic contribution. The change in the orbital moment -
Labeling Mesenchymal Cells with DMSA-Coated Gold
Silva et al. J Nanobiotechnol (2016) 14:59 DOI 10.1186/s12951-016-0213-x Journal of Nanobiotechnology RESEARCH Open Access Labeling mesenchymal cells with DMSA‑coated gold and iron oxide nanoparticles: assessment of biocompatibility and potential applications Luisa H. A. Silva1, Jaqueline R. da Silva1, Guilherme A. Ferreira2, Renata C. Silva3, Emilia C. D. Lima2, Ricardo B. Azevedo1 and Daniela M. Oliveira1* Abstract Background: Nanoparticles’ unique features have been highly explored in cellular therapies. However, nanoparti- cles can be cytotoxic. The cytotoxicity can be overcome by coating the nanoparticles with an appropriated surface modification. Nanoparticle coating influences biocompatibility between nanoparticles and cells and may affect some cell properties. Here, we evaluated the biocompatibility of gold and maghemite nanoparticles functionalized with 2,3-dimercaptosuccinic acid (DMSA), Au-DMSA and γ-Fe2O3-DMSA respectively, with human mesenchymal stem cells. Also, we tested these nanoparticles as tracers for mesenchymal stem cells in vivo tracking by computed tomography and as agents for mesenchymal stem cells magnetic targeting. Results: Significant cell death was not observed in MTT, Trypan Blue and light microscopy analyses. However, ultra- structural alterations as swollen and degenerated mitochondria, high amounts of myelin figures and structures similar to apoptotic bodies were detected in some mesenchymal stem cells. Au-DMSA and γ-Fe2O3-DMSA labeling did not affect mesenchymal stem cells adipogenesis and osteogenesis differentiation, proliferation rates or lymphocyte suppression capability. The uptake measurements indicated that both inorganic nanoparticles were well uptaken by mesenchymal stem cells. However, Au-DMSA could not be detected in microtomograph after being incorporated by mesenchymal stem cells. -
Thermal Fluctuations of Magnetic Nanoparticles: Fifty Years After Brown1)
THERMAL FLUCTUATIONS OF MAGNETIC NANOPARTICLES: FIFTY YEARS AFTER BROWN1) William T. Coffeya and Yuri P. Kalmykovb a Department of Electronic and Electrical Engineering, Trinity College, Dublin 2, Ireland b Laboratoire de Mathématiques et Physique (LAMPS), Université de Perpignan Via Domitia, 52, Avenue Paul Alduy, F-66860 Perpignan, France The reversal time (superparamagnetic relaxation time) of the magnetization of fine single domain ferromagnetic nanoparticles owing to thermal fluctuations plays a fundamental role in information storage, paleomagnetism, biotechnology, etc. Here a comprehensive tutorial-style review of the achievements of fifty years of development and generalizations of the seminal work of Brown [W.F. Brown, Jr., Phys. Rev., 130, 1677 (1963)] on thermal fluctuations of magnetic nanoparticles is presented. Analytical as well as numerical approaches to the estimation of the damping and temperature dependence of the reversal time based on Brown’s Fokker-Planck equation for the evolution of the magnetic moment orientations on the surface of the unit sphere are critically discussed while the most promising directions for future research are emphasized. I. INTRODUCTION A. THERMAL INSTABILITY OF MAGNETIZATION IN FINE PARTICLES B. KRAMERS ESCAPE RATE THEORY C. SUPERPARAMAGNETIC RELAXATION TIME: BROWN’S APPROACH II. BROWN’S CONTINUOUS DIFFUSION MODEL OF CLASSICAL SPINS A. BASIC EQUATIONS B. EVALUATION OF THE REVERSAL TIME OF THE MAGNETIZATION AND OTHER OBSERVABLES III. REVERSAL TIME IN SUPERPARAMAGNETS WITH AXIALLY-SYMMETRIC MAGNETOCRYSTALLINE ANISOTROPY A. FORMULATION OF THE PROBLEM B. ESTIMATION OF THE REVERSAL TIME VIA KRAMERS’ THEORY C. UNIAXIAL SUPERPARAMAGNET SUBJECTED TO A D.C. BIAS FIELD PARALLEL TO THE EASY AXIS IV. REVERSAL TIME OF THE MAGNETIZATION IN SUPERPARAMAGNETS WITH NONAXIALLY SYMMETRIC ANISOTROPY 1) Published in Applied Physics Reviews Section of the Journal of Applied Physics, 112, 121301 (2012). -
Dynamic Symmetry Loss of High-Frequency Hysteresis Loops in Single-Domain Particles with Uniaxial Anisotropy
Journal of Magnetism and Magnetic Materials 324 (2012) 466–470 Contents lists available at SciVerse ScienceDirect Journal of Magnetism and Magnetic Materials journal homepage: www.elsevier.com/locate/jmmm Dynamic symmetry loss of high-frequency hysteresis loops in single-domain particles with uniaxial anisotropy Gabriel T. Landi Instituto de Fı´sica da Universidade de Sao~ Paulo, 05314-970 Sao~ Paulo, Brazil article info abstract Article history: Understanding how magnetic materials respond to rapidly varying magnetic fields, as in dynamic Received 2 June 2011 hysteresis loops, constitutes a complex and physically interesting problem. But in order to accomplish a Available online 23 August 2011 thorough investigation, one must necessarily consider the effects of thermal fluctuations. Albeit being Keywords: present in all real systems, these are seldom included in numerical studies. The notable exceptions are Single-domain particles the Ising systems, which have been extensively studied in the past, but describe only one of the many Langevin dynamics mechanisms of magnetization reversal known to occur. In this paper we employ the Stochastic Landau– Magnetic hysteresis Lifshitz formalism to study high-frequency hysteresis loops of single-domain particles with uniaxial anisotropy at an arbitrary temperature. We show that in certain conditions the magnetic response may become predominantly out-of-phase and the loops may undergo a dynamic symmetry loss. This is found to be a direct consequence of the competing responses due to the thermal fluctuations and the gyroscopic motion of the magnetization. We have also found the magnetic behavior to be exceedingly sensitive to temperature variations, not only within the superparamagnetic–ferromagnetic transition range usually considered, but specially at even lower temperatures, where the bulk of interesting phenomena is seen to take place. -
Depositional Setting of Algoma-Type Banded Iron Formation Blandine Gourcerol, P Thurston, D Kontak, O Côté-Mantha, J Biczok
Depositional Setting of Algoma-type Banded Iron Formation Blandine Gourcerol, P Thurston, D Kontak, O Côté-Mantha, J Biczok To cite this version: Blandine Gourcerol, P Thurston, D Kontak, O Côté-Mantha, J Biczok. Depositional Setting of Algoma-type Banded Iron Formation. Precambrian Research, Elsevier, 2016. hal-02283951 HAL Id: hal-02283951 https://hal-brgm.archives-ouvertes.fr/hal-02283951 Submitted on 11 Sep 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Accepted Manuscript Depositional Setting of Algoma-type Banded Iron Formation B. Gourcerol, P.C. Thurston, D.J. Kontak, O. Côté-Mantha, J. Biczok PII: S0301-9268(16)30108-5 DOI: http://dx.doi.org/10.1016/j.precamres.2016.04.019 Reference: PRECAM 4501 To appear in: Precambrian Research Received Date: 26 September 2015 Revised Date: 21 January 2016 Accepted Date: 30 April 2016 Please cite this article as: B. Gourcerol, P.C. Thurston, D.J. Kontak, O. Côté-Mantha, J. Biczok, Depositional Setting of Algoma-type Banded Iron Formation, Precambrian Research (2016), doi: http://dx.doi.org/10.1016/j.precamres. 2016.04.019 This is a PDF file of an unedited manuscript that has been accepted for publication. -
Chapter 6 Antiferromagnetism and Other Magnetic Ordeer
Chapter 6 Antiferromagnetism and Other Magnetic Ordeer 6.1 Mean Field Theory of Antiferromagnetism 6.2 Ferrimagnets 6.3 Frustration 6.4 Amorphous Magnets 6.5 Spin Glasses 6.6 Magnetic Model Compounds TCD February 2007 1 1 Molecular Field Theory of Antiferromagnetism 2 equal and oppositely-directed magnetic sublattices 2 Weiss coefficients to represent inter- and intra-sublattice interactions. HAi = n’WMA + nWMB +H HBi = nWMA + n’WMB +H Magnetization of each sublattice is represented by a Brillouin function, and each falls to zero at the critical temperature TN (Néel temperature) Sublattice magnetisation Sublattice magnetisation for antiferromagnet TCD February 2007 2 Above TN The condition for the appearance of spontaneous sublattice magnetization is that these equations have a nonzero solution in zero applied field Curie Weiss ! C = 2C’, P = C’(n’W + nW) TCD February 2007 3 The antiferromagnetic axis along which the sublattice magnetizations lie is determined by magnetocrystalline anisotropy Response below TN depends on the direction of H relative to this axis. No shape anisotropy (no demagnetizing field) TCD February 2007 4 Spin Flop Occurs at Hsf when energies of paralell and perpendicular configurations are equal: HK is the effective anisotropy field i 1/2 This reduces to Hsf = 2(HKH ) for T << TN Spin Waves General: " n h q ~ q ! M and specific heat ~ Tq/n Antiferromagnet: " h q ~ q ! M and specific heat ~ Tq TCD February 2007 5 2 Ferrimagnetism Antiferromagnet with 2 unequal sublattices ! YIG (Y3Fe5O12) Iron occupies 2 crystallographic sites one octahedral (16a) & one tetrahedral (24d) with O ! Magnetite(Fe3O4) Iron again occupies 2 crystallographic sites one tetrahedral (8a – A site) & one octahedral (16d – B site) 3 Weiss Coefficients to account for inter- and intra-sublattice interaction TCD February 2007 6 Below TN, magnetisation of each sublattice is zero. -
Magnetic Switching of a Stoner-Wohlfarth Particle Subjected to a Perpendicular Bias Field
electronics Article Magnetic Switching of a Stoner-Wohlfarth Particle Subjected to a Perpendicular Bias Field Dong Xue 1,* and Weiguang Ma 2 1 Department of Physics and Astronomy, Texas Tech University, Lubbock, TX 79409-1051, USA 2 Department of Physics, Umeå University, 90187 Umeå, Sweden; [email protected] * Correspondence: [email protected]; Tel.: +1-806-834-4563 Received: 28 February 2019; Accepted: 21 March 2019; Published: 26 March 2019 Abstract: Characterized by uniaxial magnetic anisotropy, the Stoner-Wohlfarth particle experiences a change in magnetization leading to a switch in behavior when tuned by an externally applied field, which relates to the perpendicular bias component (hperp) that remains substantially small in comparison with the constant switching field (h0). The dynamics of the magnetic moment that governs the magnetic switching is studied numerically by solving the Landau-Lifshitz-Gilbert (LLG) equation using the Mathematica code without any physical approximations; the results are compared with the switching time obtained from the analytic method that intricately treats the non-trivial bias field as a perturbation. A good agreement regarding the magnetic switching time (ts) between the numerical calculation and the analytic results is found over a wide initial angle range (0.01 < q0 < 0.3), as h0 and hperp are 1.5 × K and 0.02 × K, where K represents the anisotropy constant. However, the quality of the analytic approximation starts to deteriorate slightly in contrast to the numerical approach when computing ts in terms of the field that satisfies hperp > 0.15 × K and h0 = 1.5 × K. Additionally, existence of a comparably small perpendicular bias field (hperp << h0) causes ts to decrease in a roughly exponential manner when hperp increases. -
Synthesis and Environmental Chemistry of Silver and Iron Oxide Nanoparticles
SYNTHESIS AND ENVIRONMENTAL CHEMISTRY OF SILVER AND IRON OXIDE NANOPARTICLES By SUSAN ALISON CUMBERLAND A thesis submitted to The University of Birmingham For the degree of DOCTOR OF PHILOSOPHY School of Earth and Environmental Sciences College of Life and Environmental Sciences The University of Birmingham March 2010 University of Birmingham Research Archive e-theses repository This unpublished thesis/dissertation is copyright of the author and/or third parties. The intellectual property rights of the author or third parties in respect of this work are as defined by The Copyright Designs and Patents Act 1988 or as modified by any successor legislation. Any use made of information contained in this thesis/dissertation must be in accordance with that legislation and must be properly acknowledged. Further distribution or reproduction in any format is prohibited without the permission of the copyright holder. Abstract Engineered nanoparticles are defined as having a dimension that is between one and one hundred nanometres. With toxicology studies reporting various degrees of toxicity the need to investigate nanoparticle fate and behaviour is vital. Monodispersed engineered nanoparticles were synthesised in-house to produce suitable materials to examine such processes. Iron oxide nanoparticles (5 nm) and citrate coated silver nanoparticles (20 nm) were subjected to different conditions of pH, ionic strength and different types of commercially available natural organic matter. Changes in particle size and aggregation were examined using a multi-method approach. Results showed that the natural organic matter was able to adsorb onto nanoparticle surfaces and improve their stability when subjected to changes in pH and ionic strength, where they would normally aggregate. -
Earth Systems Science Grades 9-12
Earth Systems Science Grades 9-12 Lesson 2: The Irony of Rust The Earth can be considered a family of four major components; a biosphere, atmosphere, hydrosphere, and geosphere. Together, these interacting and all-encompassing subdivisions constitute the structure and dynamics of the entire Earth. These systems do not, and can not, stand alone. This Module demonstrates, at every grade level, the concept that one system depends on every other for molding the Earth into the world we know. For example, the biosphere could not effi ciently prosper as is without gas exchange from the atmosphere, liquid water from the hydrosphere, and food and other materials provided by the geosphere. Similarly, the other systems are signifi cantly affected by the biosphere in one way or another. This Module uses Earth’s systems to provide the ultimate lesson in teamwork. March 2006 2 JOURNEY THROUGH THE UNIVERSE Lesson 2: The Irony of Rust Lesson at a Glance Lesson Overview In this lesson, students will investigate the chemistry of rust—the forma- tion of iron oxide (Fe2O3)—within a modern context, by experimenting with the conditions under which iron oxide forms. Students will apply what they have learned to deduce the atmospheric chemistry at the time that the sediments, which eventually became common iron ore found in the United States and elsewhere, were deposited. Students will interpret the necessary formation conditions of this iron-bearing rock in the context of Earth’s geochemical history and the history of life on Earth. Lesson Duration Four 45-minute class periods plus 10 minutes a day for maintence and observation for two weeks Core Education Standards National Science Education Standards Standard B3: A large number of important reactions involve the transfer of either electrons (oxidation/reduction reactions) or hydrogen ions (acid/base reactions) between reacting ions, molecules, or atoms. -
Superparamagnetic Iron Oxide Nanoparticle Probes for Molecular Imaging
University of Pennsylvania ScholarlyCommons Departmental Papers (BE) Department of Bioengineering 1-1-2006 Superparamagnetic Iron Oxide Nanoparticle Probes for Molecular Imaging Daniel L. J Thorek University of Pennsylvania, [email protected] Antony K. Chen University of Pennsylvania, [email protected] Julie Czupryna University of Pennsylvania, [email protected] Andrew Tsourkas University of Pennsylvania, [email protected] Follow this and additional works at: https://repository.upenn.edu/be_papers Part of the Molecular, Cellular, and Tissue Engineering Commons Recommended Citation Thorek, D. L., Chen, A. K., Czupryna, J., & Tsourkas, A. (2006). Superparamagnetic Iron Oxide Nanoparticle Probes for Molecular Imaging. Retrieved from https://repository.upenn.edu/be_papers/77 Postprint version. Published in Annals of Biomedical Engineering, Volume 34, Issue 1, January 2006, pages 23-38. Publisher URL: http://dx.doi.org/10.1007/s10439-005-9002-7 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/be_papers/77 For more information, please contact [email protected]. Superparamagnetic Iron Oxide Nanoparticle Probes for Molecular Imaging Abstract The field of molecular imaging has ecentlyr seen rapid advances in the development of novel contrast agents and the implementation of insightful approaches to monitor biological processes non-invasively. In particular, superparamagnetic iron oxide nanoparticles (SPIO) have demonstrated their utility as an important tool for enhancing magnetic resonance contrast, allowing