In situ microwave characterization of microwire composites with external magnetic field

This paper presents a novel approach for the characterization of microwave properties of carbon-based nanopowders, decorated or not with magnetic nanoparticles. Their microwave parameters, dielectric constant, electrical conductivity, and complex magnetic permeability are extracted from measurements performed using a single transmission line acting as a test cell. Two geometries of transmission line were tested, and successful results were obtained with each one of them. The measurement results are assessed by a phenomenological model enabling to fit the measurement of the dielectric constant and conductivity, providing an insight on the compacity quality of the powder sample. Also, the extraction of the permeability is validated by the detection of a ferromagnetic resonance showing a linear dependence on external DC magnetic field.

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Synthesis and Characterization of Cobalt-Nickel Nanowires Formed under External Magnetic Field

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.799-800.120 ◽

2015 ◽

Vol 799-800 ◽

pp. 120-124 ◽

Cited By ~ 1

Author(s):

Mary Donnabelle L. Balela ◽

Lalaine M. Dulin ◽

Erica A. Garcia ◽

M. Janelle H. Tica

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Face Centered Cubic ◽

X Ray Diffraction ◽

X Ray ◽

Hexagonal Close Packed ◽

Cobalt Nickel ◽

Nickel Nanowires ◽

Face Centered

Cobalt-nickel (Co-Ni) nanowires were formed by electroless deposition in ethylene glycol under external magnetic field. The effects of initial Co (II) and Ni (II) concentration on the surface and morphology of the synthesized nanowires were investigated by x-ray diffraction (XRD) and scanning electron microscope (SEM) respectively. An increase in the Co (II) concentration resulted in increase in diameter of the nanowires. However, the length of nanowires was observed to decrease. Higher Co (II) concentration resulted in a mixture of hexagonal close-packed and face-centered cubic Co-Ni nanowires. X-ray diffraction revealed that crystal growth occurred when the nanowires are annealed at 653 K for 10h.

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Synthesis and Microwave Characterization of Polypyrrole-PVC Blends

MRS Proceedings ◽

10.1557/proc-247-705 ◽

1992 ◽

Vol 247 ◽

Cited By ~ 43

Author(s):

F. Jousse ◽

P. Hourquebie ◽

C. Deleuze ◽

L. Olmedo

Keyword(s):

In Situ Growth ◽

Oxidizing Agent ◽

Direct Link ◽

Reaction Parameters ◽

Solvent Nature ◽

Microwave Characterization ◽

Agent Control ◽

Thermoplastic Blends

ABSTRACT.: Thermoplastic blends have been created by in situ growth of polypyrrole in an insulating PVC matrix. This type of synthesis gives a level of conductivity of the order of 10−5 to 1 S/cm for concentrations of less than 15% (in weight). A study of the synthetic conditions shows that the reaction parameters (solvent, nature of oxidizing agent) control the eventual properties of the blend (structure, conductivity level). The microwave characterization of these materials has allowed us to establish a direct link between the method of processing and the radioelectric properties.

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In situ microwave characterization of nonplanar dielectric objects

IEEE Transactions on Microwave Theory and Techniques ◽

10.1109/22.826837 ◽

2000 ◽

Vol 48 (3) ◽

pp. 388-394 ◽

Cited By ~ 26

Author(s):

V.V. Varadan ◽

K.A. Jose ◽

V.K. Varadan

Keyword(s):

Microwave Characterization ◽

Dielectric Objects

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Characterization of uniaxial stiffness of extracellular matrix embedded with magnetic beads via bio-conjugation and under the influence of an external magnetic field

Journal of the Mechanical Behavior of Biomedical Materials ◽

10.1016/j.jmbbm.2013.11.012 ◽

2014 ◽

Vol 30 ◽

pp. 253-265 ◽

Cited By ~ 6

Author(s):

Sahan C.B. Herath ◽

Yue Du ◽

Dong-an Wang ◽

Kin Liao ◽

Qingguo Wang ◽

...

Keyword(s):

Magnetic Field ◽

Extracellular Matrix ◽

External Magnetic Field ◽

Magnetic Beads

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Secondary resonance magnetic force microscopy using an external magnetic field for characterization of magnetic thin films

Applied Physics Letters ◽

10.1063/1.4930878 ◽

2015 ◽

Vol 107 (10) ◽

pp. 103110 ◽

Cited By ~ 4

Author(s):

Dongzi Liu ◽

Kangxin Mo ◽

Xidong Ding ◽

Liangbing Zhao ◽

Guocong Lin ◽

...

Keyword(s):

Magnetic Field ◽

Thin Films ◽

External Magnetic Field ◽

Magnetic Force Microscopy ◽

Magnetic Force ◽

Magnetic Thin Films ◽

Secondary Resonance ◽

Force Microscopy

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Ferro-Self-Assembly: Magnetic and Electrochemical Adaptation of a Multiresponsive Zwitterionic Metalloamphiphile Showing a Shape-Hysteresis Effect

10.26434/chemrxiv.12370406 ◽

2020 ◽

Author(s):

Stefan Bitter ◽

Moritz Schlötter ◽

Markus Schilling ◽

Rainer Winter ◽

Sebastian Polarz

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Self Assembly ◽

Hysteresis Effect ◽

The Self ◽

Stimuli Responsive ◽

Tubular Aggregates ◽

Optical Birefringence ◽

Sufficient Concentration

We report on a novel multi-stimuli-responsive amphiphile, 1-(Z)-heptenyl-1’-dimethylammonium-methyl-(3-sulfopropyl)ferrocene (6), whose self-assembly properties can be altered by three different stimuli, namely: (i) the addition of external salts which serve to unfold the sultone headgroup, thus triggering self-assembly of 6 into vesicles; (ii) oxidation to 6+, which changes the lipophilic ferrocene to a hydrophilic ferrocenium entity, thereby broadening the size-distribution of the aggregates; and (iii) exposition of 6+ to an external magnetic field of 0.8 T. Under thease conditions and at sufficient concentration, 6+ forms large, tubular aggregates with lengths of up to 15 µm, which persist for over 5 min after the field is switched off again. 6+ is thus the first amphiphile to exhibit a shape-hysteresis effect. The self-assembly/disassembly processes and their dynamics were studied live and in situ by optical birefringence measurements coupled to light scattering.

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