Search

Your search keyword '"Kim, Chorong"' showing total 196 results
Start Over Author "Kim, Chorong"
196 results on '"Kim, Chorong"'

58. Enhanced anomalous magnetization in carbonyl iron by Ni+ ion beam irradiation.

Author

Park, Jun Kue, Jang, Hye Min, Cho, Won-Je, Kim, Chorong, Suk, Jaekwon, Kim, Dong-Seok, and Lee, Jae Sang

Subjects
IRON ions, ION beams, MAGNETIZATION, IRRADIATION, MAGNETIC control, MAGNETIC properties
Abstract

We investigate the magnetic properties in carbonyl iron (CI) particles before and after Ni + and H + ion beam irradiation. Upon increasing temperatures, the saturation magnetization ( M s ) in hysteresis loops exhibits an anomalous increase at a high temperature for the unirradiated and the Ni + -beam-irradiated samples, unlike in H + -beam-irradiated sample. Moreover, the magnetization values at low and high temperatures are more intense after Ni + beam irradiation, whereas after H + beam irradiation those are remarkably suppressed. Hematite (α -Fe 2 O 3 ) phase introduced on the surface of our CI particles undergoes the Morin transition that was observed in our magnetization-temperature curves. The Morin transition causing canted antiferromagnetism above the Morin temperature was found in the unirradiated and Ni + -beam-irradiated samples, but not in H + -beam-irradiated sample. It is thus revealed that the CI particles undergoing the Morin transition cause the anomalous increase in M s . We may suggest that Ni + ion beam increases uncompensated surface spins on the CI particles resulting in a more steep Morin transition and the intensified M s . Ion-beam irradiation may thus be a good tool for controlling the magnetic properties of CI particles, tailoring our work for future applications. [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
View/download PDF

66. Initial Operation of the Low-Flux Proton Beamline at the KOMAC 100 MeV Linac

Author

Yun, Sang-Pil, Kim, Chorong, Kim, Dae-Il, Kim, Han-Sung, Kwon, Hyeok-Jung, Lee, Seok-Geun, and Song, Young-Gi

Subjects
Physics::Accelerator Physics, 04 Hadron Accelerators, Nuclear Experiment, Accelerator Physics
Abstract

Korea multi-purpose Accelerator Complex (KOMAC) has been operating 20 MeV and 100 MeV proton beamlines to provide proton beams to users since 2013. The new beamline and target irradiation facility, which is proposed applicable to development of the detector and simulation of the space radiation, have being constructed for low-flux proton utilization at this year. The new beam lines have the 100 MeV of maximum beam energy and 10 nA of maximum beam current. The new beam line was designed to operate with maximum duty 8%, the flux density of proton beam can be reduced to the 1/10,000 by the graphite collimator. The extracted proton beam energy can be adjustable by the double wedge type energy degrader and also, the beam energy can be selected by dipole magnet. In addition to the two sets of the octupole magnets were prepared for uniform beam irradiation with the ± 5% uniformity. In this paper, the initial operation results of the constructed new beam line is be described., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Published
2017
Full Text
View/download PDF

78. Design of the 100 MeV Proton Beam Line for Low Flux Application

Author

Kwon, Hyeok-Jung, Cho, Yong-Sub, Kim, Chorong, Kim, Han-Sung, Lee, Seok-Geun, Lee, Seunghyun, and Yun, Sang-Pil

Subjects
Physics::Accelerator Physics, 04 Hadron Accelerators, Accelerator Physics
Abstract

KOMAC has been operating two beam lines for user service since 2013. A new beam line was completed in 2015 for radioisotope production and has a plan to be commissioned in 2016. Another beam line was proposed to supply low flux beam to users. The maximum energy and average current are 100 MeV and 10 nA. The beam line consists of collimator, energy degrader, dipole magnet for energy separation and octupole magnet for uniform beam production. In this paper, the design of the beam line and its components is presented., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

Published
2016
Full Text
View/download PDF

79. Design of the Beam Dump for Low Flux Beamline in KOMAC

Author

Kim, Chorong, Cho, Yong-Sub, Kim, Han-Sung, and Kwon, Hyeok-Jung

Subjects
07 Accelerator Technology, Physics::Accelerator Physics, Accelerator Physics
Abstract

A linac in KOMAC (Korea Multi-Purpose Accelerator Complex) is providing users with 100-MeV proton beam for various applications. A new target room (TR102) for low dose of radiation beam will be constructed in 2016. The beam dump is an important part of this beam line and must be designed to stop 100 MeV beams with a maximum power of 10 kW. Incepting the waste of beam increases the temperature of the beam dump, which can make a structural problem. Therefore, the material of it should be robust under the high temperature and the radioactive circumstance. To ensure safety, thermo-mechanical analyses have been performed for a few materials using a finite element code. The beam dump will be fabricated based on the analysis results., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

Published
2016
Full Text
View/download PDF

90. Morphogen Gradient Creation and Bio-modified Surfaces for Rebuilding a Stem Cell Microenvironment

Author

Kim, Chorong and Wedlich, D.

Subjects
Life sciences, biology, ddc:570
Abstract

Recreation of a microenvironment where stem cells maintain pluripotency or initiate differentiation is crucial especially when they are used for therapeutic needs. In this thesis, to generate more in vivo like environments, the application of soluble factors such as morphogen gradients was realized by microfluidic system and cadherin-anchored artificial substrates were generated for the cellular contact to the microenvironment by atomic force microscope based nanografting.

Published
2012
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results