Finite-amplitude RF heating rates for magnetized electrons in neutral plasma

John M. Guthrie; Jacob L. Roberts

doi:10.1063/5.0047640

Simulations of the rf heating rates in a linear quadrupole ion trap

Physical Review A ◽

10.1103/physreva.71.033414 ◽

2005 ◽

Vol 71 (3) ◽

Cited By ~ 32

Author(s):

Vladimir L. Ryjkov ◽

XianZhen Zhao ◽

Hans A. Schuessler

Keyword(s):

Ion Trap ◽

Quadrupole Ion Trap ◽

Rf Heating ◽

Heating Rates ◽

Linear Quadrupole Ion Trap

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RF heating of magnetic nanoparticles improves the thawing of cryopreserved biomaterials

TECHNOLOGY ◽

10.1142/s2339547814500204 ◽

2014 ◽

Vol 02 (03) ◽

pp. 229-242 ◽

Cited By ~ 46

Author(s):

Michael L. Etheridge ◽

Yi Xu ◽

Leoni Rott ◽

Jeunghwan Choi ◽

Birgit Glasmacher ◽

...

Keyword(s):

Magnetic Nanoparticles ◽

Great Promise ◽

Rf Heating ◽

Practical Application ◽

Micro Computed Tomography ◽

Heating Rates ◽

Scanning Calorimetry ◽

New Approach ◽

Minimal Impact ◽

Quality Control Tool

While vitrified cryopreservation holds great promise, practical application has been limited to smaller systems (cells and thin tissues) due to diffusive heat and mass transfer limitations, which are typically manifested as devitrification and cracking failures during thaw. Here then we describe a new approach for rapidly and uniformly heating cryopreserved biospecimens with radiofrequency (RF) excited magnetic nanoparticles (mNPs). Importantly, heating rates can be increased several fold over conventional boundary heating techniques and are independent of sample size. Initial differential scanning calorimetry studies indicate that the addition of the mNPs has minimal impact on the freeze-thaw behavior of the cryoprotectant systems themselves. Then proof-of-principle experiments in aqueous and cryoprotectant solutions demonstrate the ability to heat at rates high enough to mitigate or eliminate devitrification (hundreds of °C/min) and scaled heat transfer modeling is used to illustrate the potential of this innovative approach. Finally, X-ray micro-computed-tomography (micro-CT) is investigated as a planning and quality control tool, where the density-based measurements are able to quantify changes in cryoprotectant concentration, mNP concentration, and the frozen state (i.e. crystallized versus vitrified).

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Comparing fast inductive tempering and conventional tempering: Effects on microstructure and mechanical properties

Metallurgical Research & Technology ◽

10.1051/metal/2018015 ◽

2018 ◽

Vol 115 (4) ◽

pp. 407 ◽

Cited By ~ 4

Author(s):

Annika Eggbauer Vieweg ◽

Gerald Ressel ◽

Peter Raninger ◽

Petri Prevedel ◽

Stefan Marsoner ◽

...

Keyword(s):

Mechanical Properties ◽

Impact Energy ◽

Charpy Impact ◽

Heat Treating ◽

Processing Route ◽

High Heating Rate ◽

Heating Rates ◽

High Heating ◽

Tempering Treatment ◽

Carbide Distribution

Induction heating processes are of rising interest within the heat treating industry. Using inductive tempering, a lot of production time can be saved compared to a conventional tempering treatment. However, it is not completely understood how fast inductive processes influence the quenched and tempered microstructure and the corresponding mechanical properties. The aim of this work is to highlight differences between inductive and conventional tempering processes and to suggest a possible processing route which results in optimized microstructures, as well as desirable mechanical properties. Therefore, the present work evaluates the influencing factors of high heating rates to tempering temperatures on the microstructure as well as hardness and Charpy impact energy. To this end, after quenching a 50CrMo4 steel three different induction tempering processes are carried out and the resulting properties are subsequently compared to a conventional tempering process. The results indicate that notch impact energy raises with increasing heating rates to tempering when realizing the same hardness of the samples. The positive effect of high heating rate on toughness is traced back to smaller carbide sizes, as well as smaller carbide spacing and more uniform carbide distribution over the sample.

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