Experiment and Codes to Support Safety Assessments for Sodium Fast Reactors (KASOLA, SOLTEC and KARIFA)

Abstract The experimental liquid metal (LM) loops hosted within the Karlsruhe Sodium laboratory (KASOLA) com-prise a set of facilities to study Liquid Metal (LM) flows for various types of energy applications ranging from room temperature conditions used for education and training and fundamental research up to challenges posed by multi-physics problems such as material-fluid interactions at high temperatures. Extreme conditions, such as sodium boiling, relevant to thermo-electric conversion or fast reactor safety are covered in a dedicated facility small -scale (KARIFA). The complete experimental range is comple-mented by system code support and CFD simulation. The outcome is used for validation and develop-ment allowing application not only on component but also on system scale.

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Anion ordering enables fast H− conduction at low temperatures

Science Advances ◽

10.1126/sciadv.abf7883 ◽

2021 ◽

Vol 7 (23) ◽

pp. eabf7883

Author(s):

Hiroki Ubukata ◽

Fumitaka Takeiri ◽

Kazuki Shitara ◽

Cédric Tassel ◽

Takashi Saito ◽

...

Keyword(s):

Ionic Conductivity ◽

Room Temperature ◽

Structural Transition ◽

Hexagonal Lattice ◽

Ionic Conductors ◽

Activation Barriers ◽

Energy Devices ◽

Energy Applications ◽

Chemical Disorder ◽

New Energy

The introduction of chemical disorder by substitutional chemistry into ionic conductors is the most commonly used strategy to stabilize high-symmetric phases while maintaining ionic conductivity at lower temperatures. In recent years, hydride materials have received much attention owing to their potential for new energy applications, but there remains room for development in ionic conductivity below 300°C. Here, we show that layered anion-ordered Ba2−δH3−2δX (X = Cl, Br, and I) exhibit a remarkable conductivity, reaching 1 mS cm−1 at 200°C, with low activation barriers allowing H− conduction even at room temperature. In contrast to structurally related BaH2 (i.e., Ba2H4), the layered anion order in Ba2−δH3−2δX, along with Schottky defects, likely suppresses a structural transition, rather than the traditional chemical disorder, while retaining a highly symmetric hexagonal lattice. This discovery could open a new direction in electrochemical use of hydrogen in synthetic processes and energy devices.

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Fabrication of freestanding Pt nanowires for use as thermal anemometry probes in turbulence measurements

Microsystems & Nanoengineering ◽

10.1038/s41378-021-00255-0 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Hai Le-The ◽

Christian Küchler ◽

Albert van den Berg ◽

Eberhard Bodenschatz ◽

Detlef Lohse ◽

...

Keyword(s):

Room Temperature ◽

Fluid Velocity ◽

Current Mode ◽

Constant Current ◽

Small Scale ◽

Turbulence Measurements ◽

High Dynamic ◽

Scale Turbulence ◽

Constant Current Mode ◽

Pt Nanowires

AbstractWe report a robust fabrication method for patterning freestanding Pt nanowires for use as thermal anemometry probes for small-scale turbulence measurements. Using e-beam lithography, high aspect ratio Pt nanowires (~300 nm width, ~70 µm length, ~100 nm thickness) were patterned on the surface of oxidized silicon (Si) wafers. Combining wet etching processes with dry etching processes, these Pt nanowires were successfully released, rendering them freestanding between two silicon dioxide (SiO2) beams supported on Si cantilevers. Moreover, the unique design of the bridge holding the device allowed gentle release of the device without damaging the Pt nanowires. The total fabrication time was minimized by restricting the use of e-beam lithography to the patterning of the Pt nanowires, while standard photolithography was employed for other parts of the devices. We demonstrate that the fabricated sensors are suitable for turbulence measurements when operated in constant-current mode. A robust calibration between the output voltage and the fluid velocity was established over the velocity range from 0.5 to 5 m s−1 in a SF6 atmosphere at a pressure of 2 bar and a temperature of 21 °C. The sensing signal from the nanowires showed negligible drift over a period of several hours. Moreover, we confirmed that the nanowires can withstand high dynamic pressures by testing them in air at room temperature for velocities up to 55 m s−1.

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Controlling the oxidation state of molybdenum oxide nanoparticles prepared by ionic liquid/metal sputtering to enhance plasmon-induced charge separation

RSC Advances ◽

10.1039/d0ra05165a ◽

2020 ◽

Vol 10 (48) ◽

pp. 28516-28522 ◽

Cited By ~ 3

Author(s):

Kazutaka Akiyoshi ◽

Tatsuya Kameyama ◽

Takahisa Yamamoto ◽

Susumu Kuwabata ◽

Tetsu Tatsuma ◽

...

Keyword(s):

Ionic Liquid ◽

Liquid Metal ◽

Oxidation State ◽

Molybdenum Oxide ◽

Charge Separation ◽

Room Temperature ◽

Room Temperature Ionic Liquid ◽

Oxide Nanoparticles ◽

Induced Charge ◽

Molybdenum Oxide Nanoparticles

MoOx NPs, prepared by sputtering Mo metal on a room-temperature ionic liquid (RTIL) followed by heating in air, produced anodic photocurrents with the excitation of their LSPR peak.

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Liquid–liquid phase transition in hydrogen by coupled electron–ion Monte Carlo simulations

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1603853113 ◽

2016 ◽

Vol 113 (18) ◽

pp. 4953-4957 ◽

Cited By ~ 59

Author(s):

Carlo Pierleoni ◽

Miguel A. Morales ◽

Giovanni Rillo ◽

Markus Holzmann ◽

David M. Ceperley

Keyword(s):

Phase Transition ◽

Monte Carlo ◽

Density Functional ◽

Fluid Phase ◽

Transition Line ◽

Energy Applications ◽

First Order Phase Transition ◽

Fundamental Research ◽

Diamond Anvil ◽

First Order Phase

The phase diagram of high-pressure hydrogen is of great interest for fundamental research, planetary physics, and energy applications. A first-order phase transition in the fluid phase between a molecular insulating fluid and a monoatomic metallic fluid has been predicted. The existence and precise location of the transition line is relevant for planetary models. Recent experiments reported contrasting results about the location of the transition. Theoretical results based on density functional theory are also very scattered. We report highly accurate coupled electron–ion Monte Carlo calculations of this transition, finding results that lie between the two experimental predictions, close to that measured in diamond anvil cell experiments but at 25–30 GPa higher pressure. The transition along an isotherm is signaled by a discontinuity in the specific volume, a sudden dissociation of the molecules, a jump in electrical conductivity, and loss of electron localization.

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Crack Path and Liquid Metal Embrittlement Specificity of Austenitic Steels in Mercury at Room Temperature

SSRN Electronic Journal ◽

10.2139/ssrn.3953177 ◽

2021 ◽

Author(s):

Thierry Auger ◽

Bassem Barkia ◽

Eva Héripré ◽

Vincent Michel ◽

Denis Mutel ◽

...

Keyword(s):

Liquid Metal ◽

Room Temperature ◽

Crack Path ◽

Liquid Metal Embrittlement ◽

Austenitic Steels

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Room temperature thermo-electric pumping in mid-infrared light-emitting diodes

Applied Physics Letters ◽

10.1063/1.4828566 ◽

2013 ◽

Vol 103 (18) ◽

pp. 183513 ◽

Cited By ~ 30

Author(s):

Parthiban Santhanam ◽

Duanni Huang ◽

Rajeev J. Ram ◽

Maxim A. Remennyi ◽

Boris A. Matveev

Keyword(s):

Room Temperature ◽

Light Emitting Diodes ◽

Infrared Light ◽

Thermo Electric ◽

Mid Infrared ◽

Light Emitting

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Route to Universally Tailorable Room-Temperature Liquid Metal Colloids via Phosphonic Acid Functionalization

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.8b07042 ◽

2018 ◽

Vol 122 (46) ◽

pp. 26393-26400 ◽

Cited By ~ 11

Author(s):

Zachary J. Farrell ◽

Nina Reger ◽

Ian Anderson ◽

Ellen Gawalt ◽

Christopher Tabor

Keyword(s):

Liquid Metal ◽

Phosphonic Acid ◽

Room Temperature ◽

Metal Colloids ◽

Temperature Liquid

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The Deformation Behavior and Bending Emissions of ZnO Microwire Affected by Deformation-Induced Defects and Thermal Tunneling Effect

Sensors ◽

10.3390/s21175887 ◽

2021 ◽

Vol 21 (17) ◽

pp. 5887

Author(s):

Linlin Shi ◽

Hong Wang ◽

Xiaohui Ma ◽

Yunpeng Wang ◽

Fei Wang ◽

...

Keyword(s):

Room Temperature ◽

Luminescent Properties ◽

Tunneling Effect ◽

Light Sources ◽

Electrical Characteristics ◽

Fundamental Research ◽

Induced Defects ◽

Theoretical Simulations ◽

Bright Emission

The realization of electrically pumped emitters at micro and nanoscale, especially with flexibility or special shapes is still a goal for prospective fundamental research and application. Herein, zinc oxide (ZnO) microwires were produced to investigate the luminescent properties affected by stress. To exploit the initial stress, room temperature in situ elastic bending stress was applied on the microwires by squeezing between the two approaching electrodes. A novel unrecoverable deformation phenomenon was observed by applying a large enough voltage, resulting in the formation of additional defects at bent regions. The electrical characteristics of the microwire changed with the applied bending deformation due to the introduction of defects by stress. When the injection current exceeded certain values, bright emission was observed at bent regions, ZnO microwires showed illumination at the bent region priority to straight region. The bent emission can be attributed to the effect of thermal tunneling electroluminescence appeared primarily at bent regions. The physical mechanism of the observed thermoluminescence phenomena was analyzed using theoretical simulations. The realization of electrically induced deformation and the related bending emissions in single microwires shows the possibility to fabricate special-shaped light sources and offer a method to develop photoelectronic devices.

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