scholarly journals Microwave eddy-current shielding effect in metallic films and periodic nanostructures of sub-skin-depth thicknesses and its impact on stripline ferromagnetic resonance spectroscopy

2014 ◽  
Vol 116 (17) ◽  
pp. 173905 ◽  
Author(s):  
Ivan S. Maksymov ◽  
Mikhail Kostylev
Keyword(s):  
Ferromagnetic Resonance ◽  
Eddy Current ◽  
Skin Depth ◽  
Shielding Effect ◽  
Resonance Spectroscopy ◽  
Metallic Films ◽  
Periodic Nanostructures

1H NMR Conformational Studies in Water of Angiotensin II Analogues Modified at the N- and C-Termini: Interactions of the Aromatic Side Chains and Folding of the N-Terminal Domain

1994 ◽  
Vol 59 (11) ◽  
pp. 2523-2532 ◽  
Author(s):  
John Hondrelis ◽  
John Matsoukas ◽  
George Agelis ◽  
Paul Cordopatis ◽  
Ning Zhou ◽  
...  
Keyword(s):  
Shielding Effect ◽  
Resonance Spectroscopy ◽  
Nmr Studies ◽  
Previous Suggestion ◽  
Aminoisobutyric Acid ◽  
H Nmr ◽  
Neutral Ph ◽  
Angiotensin Ii Analogues ◽  
Proton Resonances ◽  
Cosy Nmr

The conformation of [Sar1]angiotensin II in water at neutral pH has been examined by proton magnetic resonance spectroscopy at 400 MHz and in particular by comparing its 1H NMR spectral data with those of analogues modified at positions 1,4 and 6, namely [Sar1,Cha8]ANGII, [Des Asp1,Cha8]ANGII, [Aib1,Tyr(Me)4]ANGII, [Aib1,Tyr(Me)4,Ile8]ANGII, [N-MeAib1,Tyr(Me)4]ANGII, [N-MeAib1,Tyr(Me)4,Ile8]ANGII, ANGIII and [Sar1,Ile8]ANGII. Assignment of all proton resonances in these analogues was made possible by 2D COSY NMR experiments. The H-2 and H-4 protons for the histidine ring in [Sar1]ANGII, ANGII and ANGIII were shielded compared with the same protons in [Sar1,Ile8]ANGII, [Sar1,Cha8]ANGII and [Des Asp1,Cha8]ANGII; this shielding effect was not disturbed upon methylation of the tyrosine hydroxyl and/or replacement of residue 1 (sarcosine or aspartic acid) with aminoisobutyric acid (Aib) or N-methyl aminoisobutyric acid (N-MeAib). These data are consistent with our previous suggestion based on NMR studies in neutral DMSO that a characteristic folded conformation for ANGII previously observed in non-polar solvents can also be detected in water at neutral pH, but to a lesser degree.

scholarly journals ARPES and STS investigation of Shockley states in thin metallic films and periodic nanostructures

2007 ◽  
Vol 9 (10) ◽  
pp. 391-391 ◽  
Author(s):  
D Malterre ◽  
B Kierren ◽  
Y Fagot-Revurat ◽  
S Pons ◽  
A Tejeda ◽  
...  
Keyword(s):  
Metallic Films ◽  
Periodic Nanostructures

Design and first result of combined Langmuir-magnetic probe on J-TEXT tokamak

2021 ◽  
Author(s):  
Qinghu Yang ◽  
Zhipeng Chen ◽  
Zhigang Hao ◽  
Yangming Zhao ◽  
Xin Xu ◽  
...  
Keyword(s):  
Eddy Current ◽  
Magnetic Surface ◽  
Mutual Inductance ◽  
Magnetic Probe ◽  
Shielding Effect ◽  
Magnetic Fluctuations ◽  
Electromagnetic Mode ◽  
Pneumatic Device ◽  
Magnetic Fluctuation ◽  
Electromagnetic Signals

Abstract In order to measure boundary electrostatic and magnetic fluctuations simultaneously, a set of combined Langmuir-magnetic probe (CLMP) has been designed and built on Joint-Texas Experimental Tokamak (J-TEXT). The probe consists of 8 graphite probe pins and a 3D magnetic probe, driven by a mechanical pneumatic device. By means of simulation, the shielding effect of the graphite sleeve on the magnetic fluctuation signal is explored, and the influence of the eddy current was reduced by cutting the graphite sleeve. In the experiment, it has been verified that the mutual inductance of electromagnetic signals can be ignored. And a 70~90kHz electromagnetic mode is observed around the last closed magnetic surface (LCFS). The establishment of CLMP provides data for the exploration of the coupling of electrostatic and magnetic fluctuations.

scholarly journals Analysis of AC Transport Loss in Conductor on Round Core Cables

2021 ◽  
Author(s):  
Jiabin Yang ◽  
Chao Li ◽  
Mengyuan Tian ◽  
Shuyu Liu ◽  
Boyang Shen ◽  
...  
Keyword(s):  
Eddy Current ◽  
Complex Geometry ◽  
Layer Structure ◽  
Single Layer ◽  
Element Model ◽  
Structure Design ◽  
Ac Loss ◽  
Shielding Effect ◽  
Transport Loss ◽  
Electro Magnetic

AbstractThe conductor on round core (CORC) cable wound with second-generation high-temperature superconducting (HTS) tapes is a promising cable candidate with superiority in current capacity and mechanical strength. The composing superconductors and the former are tightly assembled, resulting in a strong electro-magnetic interaction between them. Correspondingly, the AC loss is influenced by the cable structure. In this paper, a 3D finite-element model of the CORC cable is first built, and it includes the complex geometry, the angular dependence of critical current and the periodic settings. The modelling is verified by the measurements conducted for the transport loss of a two-layer CORC cable. Subsequently, the simulated results show that the primary transport loss shifts from the former to the superconductors as the current increases. Meanwhile, the loss exhibited in the outer layer is larger than that of the inner layer, which is caused by the shielding effect among layers and the former. This also leads to the current inhomogeneity in CORC cables. In contrast with the two-layer case, the simulated single-layer structure indicates stronger frequency dependence because the eddy current loss in the copper former is always dominant without the cancellation of the opposite-wound layers. The core eddy current of the single structure is denser on the outer surface. Finally, the AC transport losses among a straight HTS tape, a two-layer cable and a single-layer cable are compared. The two-layer structure is confirmed to minimise the loss, meaning an even-numbered arrangement makes better use of the cable space and superconducting materials. Having illustrated the electro-magnetic behaviour inside the CORC cable, this work is an essential reference for the structure design of CORC cables.

Broadband ferromagnetic resonance spectroscopy of permalloy triangular nanorings

2012 ◽  
Vol 100 (6) ◽  
pp. 062401 ◽  
Author(s):  
J. Ding ◽  
M. Kostylev ◽  
A. O. Adeyeye
Keyword(s):  
Ferromagnetic Resonance ◽  
Resonance Spectroscopy

scholarly journals S-band ferromagnetic resonance spectroscopy and the detection of magnetofossils

2013 ◽  
Vol 10 (80) ◽  
pp. 20120790 ◽  
Author(s):  
Andreas U. Gehring ◽  
Jessica Kind ◽  
Michalis Charilaou ◽  
Inés García-Rubio
Keyword(s):  
Ferromagnetic Resonance ◽  
Uniaxial Anisotropy ◽  
Magnetotactic Bacteria ◽  
Time Frame ◽  
Resonance Spectroscopy ◽  
Verwey Transition ◽  
Geological Time ◽  
Change Of Direction ◽  
X Band ◽  
Magnetite Particles

We report the use of S-band ferromagnetic resonance (FMR) spectroscopy to compare the anisotropic properties of magnetite particles in chains of cultured intact magnetotactic bacteria (MTB) between 300 and 15 K with those of sediment samples of Holocene age in order to infer the presence of magnetofossils and their preservation in a geological time frame. The spectrum of intact MTB at 300 K exhibits distinct uniaxial anisotropy because of the chain alignment of the cellular magnetite particles and their easy axes. This anisotropy becomes less pronounced upon cooling and below the Verwey transition ( T V ) it is nearly vanished mainly owing to the change of direction of the easy axes. In a natural sample, magnetofossils were detected by uniaxial anisotropy traits similar to those obtained from cultured MTB above T V . Our comparative study emphasizes that indispensable information can be obtained from S-band FMR spectra, which offers even a better resolution than X-band FMR for discovering magnetofossils, and this in turn can contribute towards strengthening our relatively sparse database for deciphering the microbial ecology during the Earth's history.

scholarly journals Ferromagnetic Resonance Spectroscopy and Rock Magnetic Characterization of Fossil Coral Skeletons in Ishigaki Islands, Japan

Geosciences ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 400
Author(s):  
Yuho Kumagai ◽  
Norihiro Nakamura ◽  
Tetsuro Sato ◽  
Toshitaka Oka ◽  
Hirokuni Oda
Keyword(s):  
Ferromagnetic Resonance ◽  
Single Domain ◽  
Coral Skeleton ◽  
Resonance Spectroscopy ◽  
Continuous Growth ◽  
Coral Skeletons ◽  
Ishigaki Island ◽  
Biogenic Magnetite ◽  
A Chain ◽  
Fossil Coral

Skeletons of hermatypic corals (e.g., Porites) might have enormous potential as a high-resolution paleomagnetic recorder owing to their rapid and continuous growth over hundreds of years at a rate of up to 2 cm/year, although typical corals show an extremely weak intensity of remanence and low stability. We found that coral tsunami boulders with negligible amounts of calcite on Ishigaki Island show a measurable intensity of remanence; thus, we attempted to characterize the magnetic assemblages in this coral skeleton to determine whether it is of biogenic or detrital magnetite using first-order reversal curve (FORC) measurements, ferromagnetic resonance (FMR) spectroscopy, and petrological observations through field-emission type scanning electron microscope (FE-SEM) with an acid treatment. The FMR derivative spectra of coral skeleton samples represent multiple derivative maxima and extended low-field absorption, indicating the presence of intact biogenic magnetite chains. FORC diagrams represent a “central ridge” signature with a vertical spread. These FMR and FORC features indicate the magnetization of these coral skeletons that are mainly created using intact biogenic magnetites and mixtures of grains from collapsed biogenic magnetites, pseudo-single domain grains, and multi-domain grains such as detrital magnetite. FE-SEM observations confirm the presence of a chain-like structure of iron oxides corresponding to the features of biogenic magnetite. Therefore, the magnetic mineral assemblage in coralline boulders from Ishigaki Island consists of dominant biogenic-origin single-domain magnetite and a trace amount of detrital component, indicating that fossil coral skeletons in Ishigaki Island have potential for utilization in paleomagnetic studies.

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