Characterizing Complex Mineral Structures in Thin Section of Geological Sample with a Scanning Hall Effect Microscope

We improved a magnetic scanning microscope for measuring the magnetic properties of minerals in thin sections of geological samples at submillimeter scales. The microscope is comprised of a 200 µm diameter Hall sensor that is 142 µm from the sample; an electromagnet capable of applying to the sample up to 500 mT dc magnetic fields over a 40 mm diameter region; a second Hall sensor arranged in a gradiometric configuration to cancel the background signal applied by the electromagnet and reduce overall noise in the system; a custom-designed electronics to bias the sensors and provide adjustment for background signal cancelation; and a scanning XY stage with micrometer resolution. Our system achieves a spatial resolution of  220 µm with noise at 6.0 Hz of »300 nTrms/(Hz)1/2 in an unshielded environment. The magnetic moment sensitivity is 1.3 × 10−11 Am2.1/2 We successfully measured the representative magnetization of a geological sample using an alternative model that takes into account the sample geometry and identified different micrometric characteristics in the sample slice.

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Characterizing Complex Mineral Structures in Thin Sections of Geological Samples with a Scanning Hall Effect Microscope

Sensors ◽

10.3390/s19071636 ◽

2019 ◽

Vol 19 (7) ◽

pp. 1636 ◽

Cited By ~ 2

Author(s):

Jefferson Araujo ◽

Andre Reis ◽

Vanderlei Oliveira ◽

Amanda Santos ◽

Cleanio Luz-Lima ◽

...

Keyword(s):

Magnetic Properties ◽

Magnetic Moment ◽

Alternative Model ◽

Hall Sensor ◽

Geological Sample ◽

Geological Samples ◽

Scanning Microscope ◽

Background Signal ◽

Thin Sections ◽

System A

We improved a magnetic scanning microscope for measuring the magnetic properties of minerals in thin sections of geological samples at submillimeter scales. The microscope is comprised of a 200 µm diameter Hall sensor that is located at a distance of 142 µm from the sample; an electromagnet capable of applying up to 500 mT DC magnetic fields to the sample over a 40 mm diameter region; a second Hall sensor arranged in a gradiometric configuration to cancel the background signal applied by the electromagnet and reduce the overall noise in the system; a custom-designed electronics system to bias the sensors and allow adjustments to the background signal cancelation; and a scanning XY stage with micrometer resolution. Our system achieves a spatial resolution of 200 µm with a noise at 6.0 Hz of 300 nTrms/(Hz)1/2 in an unshielded environment. The magnetic moment sensitivity is 1.3 × 10−11 Am2. We successfully measured the representative magnetization of a geological sample using an alternative model that takes the sample geometry into account and identified different micrometric characteristics in the sample slice.

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Stability and magnetic properties of isomorphous substituted Si7-xMnx+

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/56/1/10506 ◽

2018 ◽

Vol 56 (1) ◽

pp. 64

Author(s):

Nguyen Thanh Tung ◽

Nguyen Thi Mai ◽

Ngo Tuan Cuong

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

Magnetic Moment ◽

Density Functional ◽

Basis Set ◽

Pentagonal Bipyramid ◽

Functional Theory ◽

Electronic Configurations ◽

Method Of Density Functional ◽

Optimized Geometries

The optimized geometries, stability, and magnetic properties of cationic clusters Si7+, Si6Mn+, and Si5Mn2+ have been determined by the method of density functional theory using the B3P86/6-311+G(d) functional/basis set. Their electronic configurations have been analyzed to understand the influence of substituting Si atoms by Mn atoms on the structural and magnetic aspects of Si7+. It is shown that the manganese dopant does not alter the structure of the silicon host but significantly changes its stability and magnetism. In particular, while the magnetic moment of Si7+ is 1 mB, Si5Mn2+ exhibits a strong magnetic moment of 9 mB and that of Si6Mn+ takes a relatively high value of 4 mB. Among studied clusters, the pentagonal bipyramid Si5Mn2+ is assigned as the most stable one.

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Ab initio calculation of magnetic properties of p-block element doped ZnO

RSC Advances ◽

10.1039/c4ra09463h ◽

2014 ◽

Vol 4 (85) ◽

pp. 45598-45602 ◽

Cited By ~ 17

Author(s):

Palash Nath ◽

Anirban Chakraborti ◽

D. Sanyal

Keyword(s):

Magnetic Properties ◽

Ab Initio ◽

Magnetic Moment ◽

Ab Initio Calculation ◽

Effective Magnetic Moment ◽

Block Element ◽

System P ◽

Doped Zno

Effective magnetic moment for Zn54O53X (X = B, C, N, F, Al, Si, P, Cl, Ga, Ge, As) system.

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Magnetic properties of the non-stoichiometric TbCo2Nix alloys

EPJ Web of Conferences ◽

10.1051/epjconf/201818504021 ◽

2018 ◽

Vol 185 ◽

pp. 04021

Author(s):

Alexander Inishev ◽

Evgeny Gerasimov ◽

Nikolay Mushnikov ◽

Pavel Terentev ◽

Vasily Gaviko

Keyword(s):

Magnetic Properties ◽

Curie Temperature ◽

Concentration Dependence ◽

Magnetic Moment ◽

Magnetic Entropy Change ◽

Entropy Change ◽

Magnetic Entropy ◽

Thermodynamic Relation ◽

Temperature Dependences

The magnetic and magnetothermal properties of the non-stoichiometric TbCo2Nix (0 ≤ x ≤ 0.2) alloys were studied. It was found that the concentration dependence of the Curie temperature and magnetic moment of the 3d-sublattice have a maximum at x = 0.025. The obtained experimental magnetic properties of the TbCo2Nix alloys were discussed under assumption that the Co magnetic moment in the compounds changes with increasing x. The magnetic entropy change was determined using the temperature dependences of the magnetization and Maxwell’s thermodynamic relation. The obtained results for TbCo2Nix were compared with those for the ErCo2Mnx alloys.

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Stability and local magnetic moment of bilayer graphene by intercalation: first principles study

RSC Advances ◽

10.1039/c8ra03343a ◽

2018 ◽

Vol 8 (35) ◽

pp. 19732-19738 ◽

Cited By ~ 4

Author(s):

Jinsen Han ◽

Dongdong Kang ◽

Jiayu Dai

Keyword(s):

Magnetic Properties ◽

Magnetic Moment ◽

First Principles ◽

Local Magnetic Moment ◽

Bilayer Graphene ◽

Intercalation Compounds ◽

First Principles Study ◽

Magnetic Elements

The migration and magnetic properties of the bilayer graphene with intercalation compounds (BGICs) with magnetic elements are theoretically investigated based on first principles study.

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Crystal Structure and Magnetic Properties of (2,2'-Dipyridyl)-(2-acetylphenolato)copper(II) Perchlorate

Zeitschrift für Naturforschung B ◽

10.1515/znb-2002-1009 ◽

2002 ◽

Vol 57 (10) ◽

pp. 1129-1132 ◽

Cited By ~ 3

Author(s):

A. Elmali ◽

Y. Elerman ◽

I. Svoboda

Keyword(s):

Crystal Structure ◽

Magnetic Properties ◽

Magnetic Susceptibility ◽

Magnetic Moment ◽

Basal Plane ◽

Effective Magnetic Moment ◽

Mixed Ligand ◽

Magnetic Susceptibility Data ◽

Susceptibility Data ◽

Dimeric Unit

The mixed-ligand dinuclear complex (2,2'-dipyridyl)-(2-acetylphenolato)copper(II) perchlorate was synthesized and its crystal structures determined. The structure consists of a dimeric unit involving a planar Cu2O2 group. The coordination sphere of the Cu atom can be described as an alongated octahedron where the basal plane is formed by the two N atoms of the 2,2'-dipyridyl molecule and the two O atoms of the acetophenon anion. Two apical Cu - O contacts complete the 4+2 coordination of the Cu atoms. They correspond to one of the O atoms of the perchlorate anion and to the O atom of the second unit. Magnetic susceptibility data obey the Curie-Weiss law with θ = -8.1(2) K. The decreasing of the effective magnetic moment from 1.94(8) μB at 300 K to 1.86(8) μB at 70 K and the negative Weiss constant indicate weak antiferromagnetic interactions between the two copper atoms in the dimeric units.

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A simple single-stage extraction method for Mo separation from geological samples for isotopic analysis by MC-ICP-MS

Journal of Analytical Atomic Spectrometry ◽

10.1039/c9ja00267g ◽

2020 ◽

Vol 35 (1) ◽

pp. 145-154 ◽

Cited By ~ 3

Author(s):

Lanping Feng ◽

Lian Zhou ◽

Wenfeng Hu ◽

Wen Zhang ◽

Baichan Li ◽

...

Keyword(s):

Extraction Method ◽

Isotopic Analysis ◽

Geological Sample ◽

Single Stage ◽

Geological Samples ◽

Column Separation ◽

Icp Ms ◽

Efficient Column ◽

Tru Resin

Simple, fast and efficient column separation of Mo from geological sample matrices using the TRU resin.

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Magnetic Properties of Quasicrystals: Effects of Disorder on Fe Magnetic Moment Formation

Science of Crystal Structures ◽

10.1007/978-3-319-19827-9_19 ◽

2015 ◽

pp. 173-177

Author(s):

R. A. Dunlap ◽

R. C. O’Handley ◽

M. E. McHenry ◽

V. Srinivas

Keyword(s):

Magnetic Properties ◽

Magnetic Moment ◽

Effects Of Disorder

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THE SARCOPLASMIC RETICULUM IN MUSCLE CELLS OF AMBLYSTOMA LARVAE

The Journal of Cell Biology ◽

10.1083/jcb.2.4.163 ◽

1956 ◽

Vol 2 (4) ◽

pp. 163-170 ◽

Cited By ~ 58

Author(s):

Keith R. Porter

Keyword(s):

Electron Microscopy ◽

Endoplasmic Reticulum ◽

Sarcoplasmic Reticulum ◽

Constant Width ◽

Muscle Cells ◽

Cell Types ◽

Thin Sections ◽

System A ◽

Structural Relationships ◽

Complex Membrane

Electron microscopy of thin sections of muscle fibers in myotomes of Amblystoma larvae has revealed the presence of a complex, membrane-limited system of canaliculi and vesicles which form a lace-like reticulum around and among the myofibrils. This seems to correspond to the sarcoplasmic reticulum of the earlier light microscopists and the endoplasmic reticulum of other cell types. The elements constituting the reticulum are disposed in a pattern which bears a constant relation to the bands of the adjacent myofibrils and is therefore repeated in each sarcomere. At the H band the system is transversely continuous but not so at other levels. Longitudinally continuity is interrupted at the Z bands where large vesicles belonging to adjacent sarcomere segments of the system face off on opposite sides of the band. The opposing faces of these vesicles are flat and separated by a space of more or less constant width, in which are located small, finger-shaped vesicles. In view of these and other close structural relationships with the myofibrils it seems appropriate to assign to the system a role in the conduction of the excitatory impulse.

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Tunable electronic structure and magnetic moment in C2N nanoribbons with different edge functionalization atoms

Physical Chemistry Chemical Physics ◽

10.1039/c7cp01359k ◽

2017 ◽

Vol 19 (23) ◽

pp. 15021-15029 ◽

Cited By ~ 7

Author(s):

Yusheng Wang ◽

Nahong Song ◽

Min Jia ◽

Dapeng Yang ◽

Chikowore Panashe ◽

...

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

Electronic Structure ◽

Magnetic Moment ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Functional Theory ◽

Electronic And Magnetic Properties

First principles calculations based on density functional theory were carried out to study the electronic and magnetic properties of C2N nanoribbons (C2NNRs).

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