scholarly journals Concentrated assemblies of magnetic nanoparticles in ionic liquids

2015 ◽  
Vol 181 ◽  
pp. 193-209 ◽  
Author(s):  
Marianna Mamusa ◽  
Juliette Sirieix-Plénet ◽  
Régine Perzynski ◽  
Fabrice Cousin ◽  
Emmanuelle Dubois ◽  
...  
Keyword(s):  
Volume Fraction ◽  
Spatial Scales ◽  
Protic Ionic Liquid ◽  
Dynamical Study ◽  
Interparticle Potential ◽  
Angle Scattering ◽  
Ethylammonium Nitrate ◽  
Added Water ◽  
Interparticle Repulsion ◽  
Concentrated Dispersions

Maghemite (γ-Fe2O3) nanoparticles (NPs) can be successfully dispersed in a protic ionic liquid, ethylammonium nitrate (EAN), by transfer from aqueous dispersions into EAN. As the aqueous systems are well controlled, several parameters can be tuned. Their crucial role towards the interparticle potential and the structure of the dispersions is evidenced: (i) the size of the NPs tunes the interparticle attraction monitoring dispersions to be either monophasic or gas–liquid-like phase separated; (ii) the nature of the initial counterion in water (here sodium, lithium or ethylammonium) and the amount of added water (<20 vol%) modulate the interparticle repulsion. Very concentrated dispersions with a volume fraction of around 25% are obtained thanks to the gas–liquid-like phase separations. Such conclusions are derived from a fine structural and dynamical study of the dispersions on a large range of spatial scales by coupling several techniques: chemical analyses, optical microscopy, dynamic light scattering, magneto-optic birefringence and small angle scattering.

Mesoscopic structure of SiC fibers by neutron and x-ray scattering

1996 ◽  
Vol 11 (5) ◽  
pp. 1169-1178 ◽  
Author(s):  
Kentaro Suzuya ◽  
Michihiro Furusaka ◽  
Noboru Watanabe ◽  
Makoto Osawa ◽  
Kiyohito Okamura ◽  
...  
Keyword(s):  
Neutron Scattering ◽  
Volume Fraction ◽  
X Rays ◽  
X Ray ◽  
Sic Fibers ◽  
X Ray Scattering ◽  
Mesoscopic Structure ◽  
Angle Scattering ◽  
Momentum Transfer Range ◽  
First Time

Mesoscopic structures of SiC fibers produced from polycarbosilane by different methods were studied by diffraction and small-angle scattering of neutrons and x-rays. Microvoids of a size of 4–10 Å in diameter have been observed for the first time by neutron scattering in a medium momentum transfer range (Q = 0.1–1.0 Å−1). The size and the volume fraction of β–SiC particles were determined for fibers prepared at different heat-treatment temperatures. The results show that wide-angle neutron scattering measurements are especially useful for the study of the mesoscopic structure of multicomponent materials.

scholarly journals Acidity and Basicity of Aqueous Mixtures of a Protic Ionic Liquid, Ethylammonium Nitrate

2008 ◽  
Vol 24 (10) ◽  
pp. 1347-1349 ◽  
Author(s):  
Ryo KANZAKI ◽  
Kuniaki UCHIDA ◽  
Xuedan SONG ◽  
Yasuhiro UMEBAYASHI ◽  
Shin-ichi ISHIGURO
Keyword(s):  
Ionic Liquid ◽  
Aqueous Mixtures ◽  
Protic Ionic Liquid ◽  
Ethylammonium Nitrate ◽  
Acidity And Basicity

Advanced Synchrotron Radiation and Neutron Scattering Techniques for Microstructural Characterization in Industrial Research

2017 ◽  
Vol 750 ◽  
pp. 53-66
Author(s):  
Fabrizio Fiori ◽  
Emmanuelle Girardin ◽  
Alessandra Giuliani ◽  
Adrian Manescu ◽  
Serena Mazzoni ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Spatial Resolution ◽  
Small Angle ◽  
3D Imaging ◽  
Volume Fraction ◽  
Rapid Development ◽  
Small Angle Scattering ◽  
Bragg Diffraction ◽  
X Rays ◽  
Angle Scattering

The rapid development of new materials and their application in an extremely wide variety of research and technological fields has lead to the request of increasingly sophisticated characterization methods. In particular residual stress measurements by neutron diffraction, small angle scattering of X-rays and neutrons, as well as 3D imaging techniques with spatial resolution at the micron or even sub-micron scale, like micro-and nano-computerized tomography, have gained a great relevance in recent years.Residual stresses are autobalancing stresses existing in a free body not submitted to any external surface force. Several manufacturing processes, as well as thermal and mechanical treatments, leave residual stresses within the components. Bragg diffraction of X-rays and neutrons can be used to determine residual elastic strains (and then residual stresses by knowing the material elastic constants) in a non-destructive way. Small Angle Scattering of neutrons or X-rays, complementary to Transmission Electron Microscopy, allows the determination of structural features such as volume fraction, specific surface and size distribution of inhomogeneities embedded in a matrix, in a huge variety of materials of industrial interest. X-ray microtomography is similar to conventional Computed Tomography employed in Medicine, allowing 3D imaging of the investigated samples, but with a much higher spatial resolution, down to the sub-micron scale. Some examples of applications of the experimental techniques mentioned above are described and discussed.

Phase behavior of water-mediated protic ionic liquid: Ethylammonium nitrate

2017 ◽  
Vol 241 ◽  
pp. 301-307 ◽  
Author(s):  
Hiroshi Abe ◽  
Masami Aono ◽  
Takahiro Takekiyo ◽  
Yukihiro Yoshimura ◽  
Akio Shimizu
Keyword(s):  
Ionic Liquid ◽  
Phase Behavior ◽  
Protic Ionic Liquid ◽  
Ethylammonium Nitrate

Small Angle Scattering from Nanocrystalline Pd

1988 ◽  
Vol 132 ◽  
Author(s):  
G. Wallner ◽  
E. Jorra ◽  
H. Franz ◽  
J. Peisl ◽  
R. Birringer ◽  
...  
Keyword(s):  
Crystallite Size ◽  
Size Distribution ◽  
Small Angle ◽  
Volume Fraction ◽  
Structural Parameters ◽  
Spatial Arrangement ◽  
Small Angle Scattering ◽  
X Rays ◽  
Angle Scattering ◽  
Log Normal

ABSTRACTThe microstructure of nanocrystalline Pd was investigated by small angle scattering of neutrons and X-rays. The samples were prepared by compacting small crystallites produced by evaporation and condensation in an inert gas atmosphere. The strong scattering signal is interpreted to arise from crystallites embedded in a matrix of incoherent interfaces. Size distributions were deduced from the scattering curves. They consist of two parts: the crystallite size distribution dictated by the production process, and a structureless contribution due to the correlation in the spatial arrangement of the crystallites. The crystallite size distribution may be described by a log-normal distribution centred at R=2nm. The characteristic form of the correlation contribution arises from the dense packing of non-spherical crystallites. From the scattering cross-section in absolute units the volume fraction vc of crystallites was obtained as vc≈0.3, and the mean atomic density ρi in the interfaces as ρi≈0.52. The change of structural parameters during thermal annealing of the samples was studied. Up to high temperatures an appreciable volume fraction of crystallites with nearly unchanged size remains along with large particles.

Electrochemical anomalies of protic ionic liquid – Water systems: A case study using ethylammonium nitrate – Water system

2016 ◽  
Vol 475 ◽  
pp. 119-125 ◽  
Author(s):  
Hiroshi Abe ◽  
Kazuya Nakama ◽  
Ryotaro Hayashi ◽  
Masami Aono ◽  
Takahiro Takekiyo ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Liquid Water ◽  
Water System ◽  
Water Systems ◽  
Protic Ionic Liquid ◽  
Ethylammonium Nitrate

Nucleation and Growth of Liquid Droplets Under a Shear Flow

1991 ◽  
Vol 248 ◽  
Author(s):  
F. Perrot ◽  
T. Baumberger
Keyword(s):  
Shear Flow ◽  
Volume Fraction ◽  
Liquid Droplets ◽  
Subsequent Growth ◽  
Two Phase ◽  
Angle Scattering ◽  
Steady Shear Flow ◽  
Mixture Volume ◽  
New Phase

AbstractPhase separation in an off-critical binary mixture is studied under an uniform and steady shear flow. The nucleation and subsequent growth of droplets in aweakly supersaturated mixture (volume fraction of the new phase smaller than 10%) is studied by small angle scattering and turbidity measurements. The completion of the nucleation process is shown to be accelerated by the shear flow. At very low supersaturation, a strong effect of shear is detected which can be related to shear-triggered nucleation. In situ measurements ’of the surface tension between the two phase-separating phases obtained by studying the deformation and tilt of the growing droplets is discussed.

Molecular-level insights into the structures, dynamics, and hydrogen bonds of ethylammonium nitrate protic ionic liquid at the liquid–vacuum interface

2020 ◽  
Vol 22 (24) ◽  
pp. 13780-13789
Author(s):  
Qin Huang ◽  
Yiping Huang ◽  
Yi Luo ◽  
Li Li ◽  
Guobing Zhou ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Ionic Liquid ◽  
Hydrogen Bonds ◽  
Molecular Dynamics Simulations ◽  
Molecular Level ◽  
Mutual Relationship ◽  
Protic Ionic Liquid ◽  
Vacuum Interface ◽  
Ethylammonium Nitrate ◽  
Dynamics Simulations

Molecular dynamics simulations have been used to systematically explore the structures, dynamics, and hydrogen bonds of ethylammonium nitrate (EAN) protic ionic liquid and their mutual relationship at the liquid–vacuum interface.

The structure factor in small-angle scattering and the effect of deviation from spherical symmetry

2011 ◽  
Vol 44 (2) ◽  
pp. 265-271 ◽  
Author(s):  
Steen Hansen
Keyword(s):  
Structure Factor ◽  
Spherical Symmetry ◽  
Short Range ◽  
Volume Fraction ◽  
Axial Ratio ◽  
Excluded Volume ◽  
Small Deviations ◽  
Angle Scattering ◽  
Ellipsoid Of Revolution ◽  
Low Volume

The effect of deviation from spherical symmetry is studied for the structure factor. This is done by combining the analytical expression for the excluded volume of an ellipsoid of revolution with the expression for the excluded volume correlation function for a sphere. This approach makes it possible to estimate the effect of small deviations from spherical symmetry as a function of axial ratio and volume fraction for relatively low volume fractions. The calculations are relevant for the case of short-range potentials where the Percus–Yevick formula is frequently applied, and indicate that even minor deviations from spherical symmetry may lead to significant effects on the structure factor at low scattering angles.

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