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Abstract  

Tritium and 14C concentration in hot spring water in Korea were determined. Tritium in the most hot spring samples could not detected and concentration range was <0.5–1.31 TU. And 14C contents were ranged 1.7–78.6 pMC. From the 3H and 14C analysis, we found some hot springs are mixed with recent groundwater and hot spring water ages were estimated from 1,940 to 32,800 years. And also, 226Ra and 228Ra were determined simultaneously in hot spring water, and some other radionuclides were also analyzed. Content distribution of 222Rn was 50–3,760 pCi/L, 226Ra was <0.003–0.15 Bq/L and 228Ra was below the detection limit.

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Abstract  

This study proposes an empirical way for determining probability of network tie formation between network actors. In social network analysis, it is a usual problem that information for determining whether or not a network tie should be formed is missing for some network actors, and thus network can only be partially constructed due to unavailability of information. This methodology proposed in this study is based on network actors’ similarities calculations by Vector-Space Model to calculate how possible network ties can be formed. Also, a threshold value of similarity for deciding whether or not a network tie should be generated is suggested in this study. Four ontology-based knowledge networks, with journal paper or research project as network actors, constructed previously are selected as the targets of this empirical study: (1) Technology Foresight Paper Network: 181 papers and 547 keywords, (2) Regional Innovation System Paper Network: 431 papers and 1165 keywords, (3) Global Sci-Tech Policy Paper Network: 548 papers and 1705 keywords, (4) Taiwan’s Sci-Tech Policy Project Network: 143 research projects and 213 keywords. The four empirical investigations allow a cut-off threshold value calculated by Vector-Space Model to be suggested for deciding the formation of network ties when network linkage information is unavailable.

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Abstract  

The nucleus23Na has been investigated by studying the primary γ-rays emitted from 53 keV neutron capture in it using a high resolution and high efficiency (100%) HPGe detector and NaI(T1) detector for anti-Compton. 24 primary γ-rays were placed in the24Na, in which 3 primary γ-rays were new ones from a (n, γ) reaction, and reported for the first time. In order to obtain an exact energy calibration within 7 MeV,56Fe(n,γ)57Fe reaction was used at thermal neutron energy. Intensity calibration was obtained from the27Al(p,γ)28Si reaction atE p=2046 keV. The neutron binding energy of24Na was determined to be 6959.75 keV.

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Two male harbour seals (Phoca vitulina; 33 and 35 years old, respectively), housed since 2002 at a zoo for exhibition purposes, developed severe, multifocal and diffuse skin lesions. Skin scrapings and microscopy for parasites as well as pure cultures for bacteria and dermatophytes were carried out to identify the aetiological agent. Skin scrapings showed that lesions appearing on the seals were caused by an infestation of Demodex mites, which is uncommon in marine mammals, and were not due to other causative agents (parasites, bacteria or dermatophytes). Treatment with amitraz (0.01%) once a week for three weeks and with ampicillin (10 mg/kg SID per os) for six days eliminated the mites and resolved the clinical signs of demodectic mange in the harbour seals. The purpose of this report is to describe the successful treatment of naturally acquired demodectic mange with amitraz in harbour seals.

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Abstract

This paper addresses the profiling of research papers on ‘standardization and innovation’—exploring major topics and arguments in this field. Drawing on 528 papers retrieved from the database, Web of Science, we employed trend, factor, and clustering analyses to demonstrate that the standardization and innovation research has continuously grown from publication of 13 papers in 1995 to 68 papers in 2008; the majority of these papers have been published in the six subject group domains of management, economics, environment, chemistry, computer science, and telecommunications. Technology innovation management specialty journals are the most central sources favorable for these themes. We also present an exploratory taxonomy that offers nine topical clusters to demonstrate the contextual structures of standardization and innovation. The implications of our results for ongoing consistent policy and future research into standardization and innovation are discussed.

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Abstract  

The manganese sulphate bath method is widely used for measurements of neutron source strength. In this study, the analytical chemistry method based on the Inductively Coupled Plasma (ICP) spectrometry was used for examining the impurity contents of MnSO4·H2O, to induce55Mn(n,γ)56Mn reactions. From the analytical results, mainly K, Co, and Zn as well as trace amounts of Cd, Li, etc., have turned out to be the relevant impurities absorbing the neutrons and the fraction of neutron absorbed by the total impurities was determined to be 1.37%.

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Abstract  

A new two-step process was investigated to treat LiCl molten salt waste containing volatile radionuclides generated from an electro-metallurgical processing (pyro-processing) of spent oxide fuels. First, the chemical form of the soluble LiCl waste was transformed into a chloride-free and less soluble hydroxide compound by an electrochemical method, where an electrolytic de-chlorination was performed without adding any chemical salt. Then, a gelation process of the chemical form-changed Li compound, named gel-route stabilization/solidification (GRSS) system aimed to reduce the volatility of the radionuclides greatly, was introduced to stabilize/solidify the hydroxide salt wastes. The application of the electrochemical dechlorination/transformation process and the subsequent gel-route stabilization process to treat the soluble LiCl salt wastes was found to be effective.

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Abstract  

Collisional processes involving a negative muon in the deuterium and tritium system were studied using the classical binary encounter theory. The time needed for slowing down of a 10 keV muon was found to be of the order of 10–8s to 10–12s, depending on the density of the system. The Sticking Probabilities for the d-t and d-d fusions were obtained to be 0.48% and 10.2%, respectively. The usefulness of the classical model for understanding fundamental processes in muon catalyzed fusion is suggested.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Kwang-Pill Lee
,
Sun-Tae Hwang
,
Y. Yamada
,
K. Furukawa
, and
Shin-Ichi Ohno

Abstract  

Impact of energetic heavy particles on europium compound surfaces gives rise to radiative optical emission from reflected and sputtered particles and from the excited states of the solid compounds. In the present paper we discuss the optical spectrum and the sputtered secondary ion mass spectrum observed when solid europium oxide (Eu2O3) and europium chloride (EuCl3) are bombarded with 90 keV Ar+ ions from an ion accelerator. We observe the reduction reaction in solid europium chloride (EuCl3) by bombardment with a 20 A/cm2 beam of 90 keV Ar+ ions.

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Reaction Kinetics, Mechanisms and Catalysis
Authors:
Bo-Hyun Kim
,
Tae-Hee Lim
,
Jin-Woong Roh
,
Sang-Geun Lee
,
Chang Ju
,
Seong Park
,
Seong Hong
, and
Gun Lee

Abstract  

Undoped and Cr-doped Bi12TiO20 (BTO) were prepared and used as photocatalysts for the degradation of formic acid both under visible light and UV irradiation. The effects of the Cr doping on the visible light response and the photocatalytic activity of BTO were investigated. The prepared catalysts were characterized by using XRD, XPS, UV–Vis diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) spectroscopy. The doping of Bi12TiO20 with low concentration of Cr leads to noticeable increase in visible light absorption and decrease in the recombination rate of photo-generated electrons and holes. As a result, the Cr-doped BTO showed a higher photocatalytic activity for the degradation of formic acid both under visible light and UV irradiation, as compared with undoped BTO.

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