• Title/Summary/Keyword: high energy physics

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An Analysis of the Definition and the Meaning Used for the Terms of Heat and Thermal Energy in the Science Textbooks (과학과 교과서에 나타난 열과 열에너지 용어의 정의 및 사용 의미 분석)

  • Kim, Serim;Park, Jong-Yoon
    • Journal of the Korean Chemical Society
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    • v.62 no.3
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    • pp.214-225
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    • 2018
  • In this study, we tried to find out how heat and thermal energy terms are defined and used in Korean science textbooks, and to see if there are any differences in the meaning of these terms used in different areas of science. For this purpose, the contents of 52 science textbooks of elementary, middle and high school published by the 2009 revised curriculum were analyzed. The definition of the term heat is given in the middle school Science(1) and the high school Physics I and II textbooks. Most textbooks define heat as "energy transferred due to a temperature difference (Type I)". Only one textbook of Physics I defines heat as "transfer of energy due to a temperature difference (Type II)". The definition of thermal energy is mostly presented in the middle school Science (2) and the high school Physics I textbooks. Physics I textbooks define the thermal energy as "molecular kinetic energy (Type III)", while Science(2) textbooks define it as Type I or "energy causes temperature change or phase transition of matter (Type IV)". In the texts of textbooks, heat is mainly used as the meaning of Type I or Type III. Thermal energy is mainly used as Type III, but it is also used as Type I in the high school Physics and Chemistry textbooks. The meanings of heat and thermal energy terms used are differed by the area of science. They are mainly used as type I or type III in Physics and Chemistry textbooks, and used as type III in Life Science and Earth Science textbooks.

The Summary of Researches on ADS in China

  • Haihong Xia;Zhixiang Zhao;Jigen Li;Yongqian Shi;Yinlu Han;Shengyun Zhu;Yongli Xu;Xialing Guan;Shinian Fu;Baoqun Cui
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.11b
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    • pp.76-85
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    • 2005
  • The conceptual study of Accelerator Driven System (ADS) had lasted for about five years and ended in 1999 in China. As one project of 'the major state basic research program (973)' in energy domain, which is sponsored by the China Ministry of Science and Technology (MOST), a five years program of basic research for ADS physics and related technology has been launched since 2000 and passed national review last month. CIAE (China Institute of Atomic Energy), IHEP (Institute of High Energy Physics), PKU-IHIP (Institute of Heavy Ion Physics in Peking University) and other institutions are jointly carrying on the research. The research activities are focused on HPPA physics and technology, reactor physics of external source driven sub-critical assembly, nuclear data base and material study. For HPPA, a high current injector consisting of an ECR ion source, LEBT and a RFQ accelerating structure of 3.5MeV has been built. In reactor physics study, a series of neutron multiplication experimental study has been carried out and is being carrying on. The VENUS facility has been constructed as the basic experimental platform for the neutronics study in ADS blanket. It's a zero power sub-critical neutron multiplying assembly driven by external neutron produced by a pulsed neutron generator. The theoretical, experimental and simulation study on nuclear data, material properties and nuclear fuel circulation related to ADS is carrying on to provide the database for ADS system analysis. The main results on ADS related researches will be reported.

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Collaborative Tools in High Energy Physics and EVO Server at KISTI (고에너지물리를 위한 협업환경 도구와 KISTI EVO 서버)

  • KIM, Hyunwoo;CHO, Kihyeon
    • Proceedings of the Korea Contents Association Conference
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    • 2007.11a
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    • pp.234-237
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    • 2007
  • We report on our experience on utilization of collaborative tools for KISTI high energy physics group. Our main subject will be the new EVO (Enabling Virtual Organization) server that we hosted recently at KISTI. The EVO is a next generation collaborative tool from CalTech high energy physics group with several improvements from its predecessor VRVS (Virtual Room Videoconferencing System). EVO has the same baseline structure as in VRVS. The network of servers lies at the heart of EVO structure and one server called Panda communicates with local clients called Koala.

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Design of a High Temperature Oven for Measuring the Saturation Intensity of Samarium atom by using Two Wave Mixing

  • Ko, Kwang-Hoon;Moon, Hee-Jong;Park, Hyun-Min;Lee, Jong-Min;Lee, Won-Kyu;Lee, Jai-Hyung;Chang, Joon-Sung
    • Journal of the Optical Society of Korea
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    • v.4 no.2
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    • pp.75-78
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    • 2000
  • We design a high temperature oven for measuring the saturation intensity of the transition line $4f^ 6/6s^{2 7}7F_0 ↔ 4f^6/6s6p $^1$P(J = 1)$ of the samarium atom. We first constructed a high temperature oven to generate the samarium vapor column and study the thermal characteristics of the oven. The oven is able to operate at a temperature up to about 1400 $^{\circ}C$ and the operation is tested by using several metals with high melting points. We describe two wave mixing experiment with the samarium vapor generated in the high temperature oven and obtain the saturation intensity by analyzing the first diffraction signal.

Synthesis of Vertically Aligned Single-Walled Carbon Nanotubes by Thermal Chemical Vapor Deposition (열 화학기상증착법을 이용한 수직 정렬된 단일벽 탄소나노튜브의 합성)

  • Jang, Sung-Won;Song, Woo-Seok;Kim, Yoo-Seok;Kim, Sung-Hwan;Park, Sang-Eun;Park, Chong-Yun
    • Journal of the Korean Vacuum Society
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    • v.21 no.2
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    • pp.113-119
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    • 2012
  • Carbon nanotubes have emerged as a promising material for multifaceted applications, such as composited nanofiber, field effect transistors, field emitters, gas sensors due to their extraordinary electrical and physical properties. In particular, synthesis of vertically aligned carbon nanotubes with a high aspect ratio has recently attracted attention for many applications. However, mass production of high-quality single-walled carbon nanotubes is still remain elusive. In this study, an effect of chemical vapor deposition conditions, including catalyst thickness, feedstock flow rate, and growth temperature, on synthesis of carbon nanotube was systematically investigated.

Observation of Residual PMMA on Graphene Surface by Using IR-Absorption Mapping

  • Oh, Hye Min;Kim, Yong Hwan;Kim, Hyojung;Park, Doo Jae;Lee, Young Hee;Jeong, Mun Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.292.2-292.2
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    • 2013
  • Graphene, a two-dimensional graphite material consisting of sp2-hybridized carbons. The properties of graphene such as extremely high carrier mobility, high thermal conductivity, low resistivity, large specific make it a promising materail of divices and material. Typically, poly (methyl methacrylate) (PMMA) is used when graphene transfer to other substrates. To remove PMMA on graphene, people used to dip the graphene into the acetone. However, it is known that the remove of PMMA on the graphene is difficult to completely using the acetone. Therefore, to remove the PMMA on the graphene surface, many research groups have employed various methods such as the thermal treatment, photothermal method, and other solvent. Nevertheless, a part of PMMA still remain on graphene surface. Usually, to observe the residual PMMA on graphene surface, topography of graphene surface scanned by atomic force microscopy is used. However, in that case, we can not distinguish PMMA and other particles. In this study, to confirm the residual PMMA on graphene surface, we employed novel measurement technique which is available to distinguish PMMA and other particles by means of photothermal effect.

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Halide Perovskite Single Crystals (할라이드 페로브스카이트 단결정)

  • Choi, Jin San;Jo, Jae Hun;Woo, Do Hyun;Hwang, Young-Hun;Kim, Ill Won;Kim, Tae Heon;Ahn, Chang Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.34 no.5
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    • pp.283-295
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    • 2021
  • For the last decades, a research hotspot for the halide perovskites (HPs) is now showing great progress in terms of improving efficiency for numerous photovoltaic devices (PVDs). However, it still faces challenges in the case of long-term stability in the air atmosphere. Defect-free high-quality HP single crystals show their promising properties for the remarkable development of highly efficient and stable PVDs. Here, we summarize the growth processing routes for the stable HP single crystals as well as briefly discuss the pros and cons of those well-established synthesis routes. Furthermore, we briefly include the comparison note between the HP single crystals and polycrystalline perovskite films regarding their device applications. Based on the future progress, the review concludes subjective perspectives and current challenges for the development of HPs high-quality PVDs.

Fe3O4/CoFe2O4 superlattices; MBE growth and magnetic properties

  • Quang, Van Nguyen;Shin, Yooleemi;Duong, Anh Tuan;Nguyen, Thi Minh Hai;Cho, Sunglae;Meny, Christian
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.242-242
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    • 2016
  • Magnetite, Fe3O4, is a ferrimagnet with a cubic inverse spinel structure and exhibits a metal-insulator, Verwey, transition at about 120 K.[1] It is predicted to possess as half-metallic nature, 100% spin polarization, and high Curie temperature (850 K). Cobalt ferrite is one of the most important members of the ferrite family, which is characterized by its high coercivity, moderate magnetization and very high magnetocrystalline anisotropy. It has been reported that the CoFe2O4/Fe3O4 bilayers represent an unusual exchange-coupled system whose properties are due to the nature of the oxide-oxide super-exchange interactions at the interface [2]. In order to evaluate the effect of interface interactions on magnetic and transport properties of ferrite and cobalt ferrite, the CoFe2O4/Fe3O4 superlattices on MgO (100) substrate have been fabricated by molecular beam epitaxy (MBE) with the wave lengths of 50, and $200{\AA}$, called $25{\AA}/25{\AA}$ and $100{\AA}/100{\AA}$, respectively. Streaky RHEED patterns in sample $25{\AA}/25{\AA}$ indicate a very smooth surface and interface between layers. HR-TEM image show the good crystalline of sample $25{\AA}/25{\AA}$. Interestingly, magnetization curves showed a strong antiferromagnetic order, which was formed at the interfaces.

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