Excimer laser-induced ablation of clean and CO-covered polycrystalline copper surfaces: Generation and characterization of high energy copper species

In this research, the aim relates to the material characterization of high-energy lithium-ion pouch cells. The development of appropriate model cell behavior is intended to simulate two scenarios: the first is mechanical deformation during a crash and the second is an internal short circuit in lithium-ion cells during the actual effect scenarios. The punch test has been used as a benchmark to analyze the effects of different state of charge conditions on high-energy lithium-ion battery cells. This article explores the impact of three separate factors on the outcomes of mechanical punch indentation experiments. The first parameter analyzed was the degree of prediction brought about by experiments on high-energy cells with two different states of charge (greater and lesser), with four different sizes of indentation punch, from the cell’s reaction during the indentation effects on electrolyte. Second, the results of the loading position, middle versus side, are measured at quasi-static speeds. The third parameter was the effect on an electrolyte with a different state of charge. The repeatability of the experiments on punch loading was the last test function analyzed. The test results of a greater than 10% state of charge and less than 10% state of charge were compared to further refine and validate this modeling method. The different loading scenarios analyzed in this study also showed great predictability in the load-displacement reaction and the onset short circuit. A theoretical model of the cell was modified for use in comprehensive mechanical deformation. The overall conclusion found that the loading initiating the cell’s electrical short circuit is not instantaneously instigated and it is subsequently used to process the development of a precise and practical computational model that will reduce the chances of the internal short course during the crash.

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Development and characterization of Nb3Sn/Al2O3 superconducting multilayers for particle accelerators

Scientific Reports ◽

10.1038/s41598-021-87119-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Chris Sundahl ◽

Junki Makita ◽

Paul B. Welander ◽

Yi-Feng Su ◽

Fumitake Kametani ◽

...

Keyword(s):

High Performance ◽

High Energy ◽

Particle Accelerators ◽

Quality Factors ◽

Critical Fields ◽

Linear Accelerators ◽

Cross Sectional ◽

Low Field ◽

Superconducting Radio Frequency

AbstractSuperconducting radio-frequency (SRF) resonator cavities provide extremely high quality factors > 1010 at 1–2 GHz and 2 K in large linear accelerators of high-energy particles. The maximum accelerating field of SRF cavities is limited by penetration of vortices into the superconductor. Present state-of-the-art Nb cavities can withstand up to 50 MV/m accelerating gradients and magnetic fields of 200–240 mT which destroy the low-dissipative Meissner state. Achieving higher accelerating gradients requires superconductors with higher thermodynamic critical fields, of which Nb3Sn has emerged as a leading material for the next generation accelerators. To overcome the problem of low vortex penetration field in Nb3Sn, it has been proposed to coat Nb cavities with thin film Nb3Sn multilayers with dielectric interlayers. Here, we report the growth and multi-technique characterization of stoichiometric Nb3Sn/Al2O3 multilayers with good superconducting and RF properties. We developed an adsorption-controlled growth process by co-sputtering Nb and Sn at high temperatures with a high overpressure of Sn. The cross-sectional scanning electron transmission microscope images show no interdiffusion between Al2O3 and Nb3Sn. Low-field RF measurements suggest that our multilayers have quality factor comparable with cavity-grade Nb at 4.2 K. These results provide a materials platform for the development and optimization of high-performance SIS multilayers which could overcome the intrinsic limits of the Nb cavity technology.

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Experimental characterization of high-energy component in extracted pulsed neutrons at the J-PARC spallation neutron source

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2021.165252 ◽

2021 ◽

pp. 165252

Author(s):

Masahide Harada ◽

Makoto Teshigawara ◽

Motoki Ohi ◽

Kenichi Oikawa ◽

Hiroshi Takada ◽

...

Keyword(s):

Neutron Source ◽

High Energy ◽

Spallation Neutron Source ◽

Experimental Characterization ◽

Energy Component ◽

High Energy Component

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Spectral Decomposition of the Flow and Characterization of the Sound Signals through Stenoses with Different Levels of Severity

Bioengineering ◽

10.3390/bioengineering8030041 ◽

2021 ◽

Vol 8 (3) ◽

pp. 41

Author(s):

Fardin Khalili ◽

Peshala T. Gamage ◽

Amirtahà Taebi ◽

Mark E. Johnson ◽

Randal B. Roberts ◽

...

Keyword(s):

Pressure Fluctuations ◽

High Energy ◽

Sound Sources ◽

Severity Level ◽

Non Invasive ◽

Flow Through ◽

Severity Of The Disease ◽

Proper Orthogonal ◽

Different Levels

Treatments of atherosclerosis depend on the severity of the disease at the diagnosis time. Non-invasive diagnosis techniques, capable of detecting stenosis at early stages, are essential to reduce associated costs and mortality rates. We used computational fluid dynamics and acoustics analysis to extensively investigate the sound sources arising from high-turbulent fluctuating flow through stenosis. The frequency spectral analysis and proper orthogonal decomposition unveiled the frequency contents of the fluctuations for different severities and decomposed the flow into several frequency bandwidths. Results showed that high-intensity turbulent pressure fluctuations appeared inside the stenosis for severities above 70%, concentrated at plaque surface, and immediately in the post-stenotic region. Analysis of these fluctuations with the progression of the stenosis indicated that (a) there was a distinct break frequency for each severity level, ranging from 40 to 230 Hz, (b) acoustic spatial-frequency maps demonstrated the variation of the frequency content with respect to the distance from the stenosis, and (c) high-energy, high-frequency fluctuations existed inside the stenosis only for severe cases. This information can be essential for predicting the severity level of progressive stenosis, comprehending the nature of the sound sources, and determining the location of the stenosis with respect to the point of measurements.

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Introducing the HD+B model for pulsar wind nebulae: a hybrid hydrodynamics/radiative approach

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1052 ◽

2020 ◽

Vol 494 (3) ◽

pp. 4357-4370

Author(s):

B Olmi ◽

D F Torres

Keyword(s):

Gamma Ray ◽

High Energy ◽

Theoretical Modelling ◽

X Rays ◽

Pulsar Wind Nebulae ◽

New Approach ◽

Energy Gamma ◽

Radiative Model ◽

Pulsar Wind

ABSTRACT Identification and characterization of a rapidly increasing number of pulsar wind nebulae is, and will continue to be, a challenge of high-energy gamma-ray astrophysics. Given that such systems constitute -by far- the most numerous expected population in the TeV regime, such characterization is important not only to learn about the sources per se from an individual and population perspective, but also to be able to connect them with observations at other frequencies, especially in radio and X-rays. Also, we need to remove the emission from nebulae in highly confused regions of the sky for revealing other underlying emitters. In this paper, we present a new approach for theoretical modelling of pulsar wind nebulae: a hybrid hydrodynamic-radiative model able to reproduce morphological features and spectra of the sources, with relatively limited numerical cost.

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Influence of Adding Encapsulated Phase Change Materials in Aerial Lime Based Mortars

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.687.255 ◽

2013 ◽

Vol 687 ◽

pp. 255-261 ◽

Cited By ~ 19

Author(s):

Sandra Cunha ◽

José Barroso Aguiar ◽

Victor Ferreira ◽

António Tadeu

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Renewable Energy Sources ◽

High Growth ◽

High Energy ◽

High Growth Rate ◽

Aesthetic Appearance ◽

Hardened State ◽

High Energy Consumption

Increasingly in a society with a high growth rate and standards of comfort, the need to minimize the currently high energy consumption by taking advantage of renewable energy sources arises. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing for an increase in the level of thermal comfort and reduction of the use of heating, ventilation and air conditioning (HVAC) equipment, using only the energy supplied by the sun. However, the incorporation of PCM in mortars modifies some of its characteristics. Therefore, the main objective of this study was the characterization of mortars doped with two different phase change materials. Specific properties of different PCM, such as particle size, shape and enthalpy were studied, as well as the properties of the fresh and hardened state of these mortars. Nine different compositions were developed which were initially doped with microcapsules of PCM A and subsequently doped with microcapsules of PCM B. It was possible to observe that the incorporation of phase change materials in mortars causes differences in properties such as compressive strength, flexural strength and shrinkage. After the study of the behaviour of these mortars with the incorporation of two different phase change materials, it was possible to select the composition with a better compromise between its aesthetic appearance, physical and mechanical characteristics.

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