• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.23-28
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• 2001

A study was carried out to establish a detection method of irradiated shellfish through thermoluminescence (TL). The TL intensity of first glow curves for irradiated bloody, freshwater, and short-neck shellfish increased from control until 5 kGy and increased slightly room 5 kGy until 10 kGy. Maximum TL temperatures of all irradiated samples tested were below 23$0^{\circ}C$, within temperature interval of 150~25$0^{\circ}C$ recommended for evaluation. Since just in control, glow curve ratios of G3 and G4 calculated from re-irradiated (1 kGy) bloody, freshwater and shortneck were over 0.5, detection in control was possible. However, as glow curve ratios after three months were below 0.5, detection by glow curve ratios after three months was impossible. Gl, which calculated from unirradiated samples, exhibited below 0.1, they were classified as unirradiated. In all samples, all the irradiated shellfish could be classified correctly as irradiated by hemaximum TL temperatures and shape of the second glow curve because those were shown in a lower temperature region than those of the first glow curve.

• Journal of the Speleological Society of Korea
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• no.71
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• pp.5-11
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• 2006

A theoretical investigation of the solid phase mechanochemical synthesis of nano sized target product on the basis of dilution of the initial powdered reagent mixture by another product of an exchange reaction is presented. On the basis of the proposed 3 mode particle size distribution in mechanically activated mixture, optimal molar ratios of the components in mixture are calculated, providing the occurrence of impact friction contacts of reagent particles and excluding aggregation of the nanosized particles of the target reaction product. Derivation of kinetic equations for mechanochemical synthesis of nanoscale particles by the final product dilution method in the systems of exchange reactions is submitted. On the basis of obtained equations the necessary times of mechanical activation for complete course of mechanochemical reactions are designed. Kinetics of solid phase mechanosynthesis of nano TlCl by dilution of initial (2NaCl+$Tl_2SO_4$) mixture with the exchange reaction product (diluent,$zNa_2SO_4$, z=z*=11.25) was studied experimentally. Some peculiar features of the reaction mechanism were found. Parameters of the kinetic curve of nano TlCl obtained experimentally were compared with those for the model reaction KBr+TlCl+zKCl=(z+1) KCl+TlBr (z=z1*=13.5), and for the first time the value of mass transfer coefficient in a mechanochemical reactor with mobile milling balls was evaluated. Dynamics of the size change was followed for nanoparticle reaction product as a function of mechanical activation time.

• Journal of Animal Science and Technology
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• v.47 no.2
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• pp.233-242
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• 2005

Effects of supplemental charcoal powder and vitamin A on growth performance, serum profile and carcass characteristics with 24 Hanwoo steers were inves$\ell$ated. The Hanwoo steers were randomly assigned to one of the three dietary treatments: 1) Control(commercial feed), 2) Tl(commercial feed supplemented with 2% charcoal powder and 0.2 % vitamin A), 3) T2(commercial feed with 2 % charcoal powder). In the age 26 month, body weight of control Tl and T2 were 633.8 kg, 621.0 kg, 619.4 kg, respectively, with not significantly different(P> 0.05). The daily weight gain of control was the highest followed by Tl and T2. The contents of vitamin A(retinol) and total cholesterol in the blood of Tl was higher Tl(56.32 $\ell$ / dt, 163.83 mg/ dz) than the other treatment groups(P < 0.05). The average of WBC value in the blood was 6.86-" 9.83 k / ${\mu}\ell$, RBC value was 7.98 - 11.26 k / ${\mu}\ell$ and blood platelet was 236.7 - 287.0 k / ${\mu}\ell$. But The serum profile in blood was not significantly different between control and treatment groups. The carcass grade and characteristics of all treatments in Hanwoo steers were not significantly different except the texture.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.2
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• pp.116-123
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• 2015

This paper proposed a new formula for predicting acoustic power transmission loss of simple expansion chamber with two internal partitions. Seventeen cases of computational results were performed and the database was constructed for the TL according to the various positions of internal partitions. Using this database, firstly, the formula for the peak values of TL at certain frequencies was developed using the least square estimation. Secondly, the formula for the TL curve could be obtained automatically with the input data of the positions of two internal partitions. The formula of TL developed in this paper showed good agreement with computational results. This formula will be helpful for the positioning of internal partitions to improve TL at target frequencies.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05a
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• pp.38-41
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• 2003

상업용 Ag 판재 위에 cyclic 전위와 일정 전위를 인가하는 전기증착법으로 Tl-1223상 precursor 막을 증착하는 연구를 수행한 다음, 이를 이영역 전기로를 사용하여 열처리함으로써 고온초전도 coated conductors를 제조하는 연구를 수행하였다. 전기증착법으로 비교적 균질하고 치밀한 precursor막을 증착할 수 있었으며, 이 막을 $870^{\circ}C$에서 20분 동안 열처리하여 임계온도가 114 K이고 자속고정능력도 비교적 우수한 50%의 Tl-1223상과 50%의 Tl-1212상으로 구성된 고온초전도 도체를 제조할 수 있었다. 이로부터 아주 값싼 증착법인 전기증착법을 이용하여 후막의 고온초전도 도체를 제조할 수 있음을 증명하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.405-406
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• 2005

A theoretical investigation of the solid-phase mechanochemical synthesis of nano-sized target product on the basis of dilution of the initial powdered reagent mixture by another product of an exchange reaction is presented. On the basis of the proposed 3-mode particle size distribution in mechanically activated mixture, optimal molar ratios of the components in mixture are calculated, providing the occurrence of impact-friction contacts of reagent particles and excluding aggregation of the nanosized particles of the target reaction product. Derivation of kinetic equations for mechanochemical synthesis of nanoscale particles by the final product dilution method in the systems of exchange reactions is submitted. On the basis of obtained equations the necessary times of mechanical activation for complete course of mechanochemical reactions are designed. Kinetics of solid phase mechanosynthesis of nano-TlCl by dilution of initial (2NaCl + $Tl_2SO_4$) mixture with the exchange reaction product (diluent, $zNa_2SO_4$, $z=z^*=11.25$) was studied experimentally. Some peculiar features of the reaction mechanism were found. Parameters of the kinetic curve of nano-TlCl obtained experimentally were compared with those for the model reaction KBr + TlCl + zKCl = (z + 1) KCl + TlBr ($z=z_l^*=13.5$), and for the first time the value of mass transfer coefficient in a mechanochemical reactor with mobile milling balls was evaluated. Dynamics of the size change was followed for nanoparticle reaction product as a function of mechanical activation time.

• Journal of the Korean Physical Society
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• v.73 no.9
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• pp.1370-1376
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• 2018

The electronic structures, magnetic properties and half-metallicity in $Zr_2RuZ$ (Z = Ga, In, Tl, Ge, Sn, and Pb) alloys with $AlCu_2Mn-$ and $CuHg_2Ti$-type structures were investigated using first-principles density functional theory (DFT) calculations. The calculations showed that $Zr_2RuIn$, $Zr_2RuTl$, $Zr_2RuSn$, and $Zr_2RuPb$ compounds with $CuHg_2Ti$-type structures were half-metallic ferromagnets with half-metallic band gaps of 0.18, 0.24, 0.22, and 0.27 eV, respectively. The half-metallicity originated from d-d and covalent hybridizations between the transition metals Zr and Ru. The total magnetic moments of the $Zr_2RuZ$ (Z = In, Tl, Sn, and Pb) compounds with $CuHg_2Ti$-type structures were integer values of $1{\mu}B$ and $2{\mu}B$, which is in agreement with Slater-Pauling rule ($M_{tot}=Z_{tot}-18$). Among these compounds, $Zr_2RuIn$ and $Zr_2RuTl$ were half-metals over relatively wide regions of the lattice constants, indicating that these two new Heusler alloys are ideal candidates for use in spintronic devices.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.1
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• pp.44-53
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• 2023

In this study, the morphological development and early life cycle of larvae and juvenile Rhinogobius brunneus found in Wicheon, Nakdong River, Korea, were investigated. The fertilized eggs were 2.20×0.68 mm (long×short) in diameter. The eggs began hatching approximately 104 h after fertilization at water temperatures of 17.3-20.5℃ (mean 18.9±1.6℃). The newly hatched yolk-sac larvae were 3.71±0.06 mm in total length (TL), with an unopened anus. Three days after hatching, the preflexion larvae were 4.37±0.16 mm in TL with yolk absorption. Twenty days after hatching, the flexion larvae were 6.50±0.22 mm in TL and the tip of the notochord was bent upward. Twenty-seven days after hatching, the postflexion larvae were 11.8±0.63 mm in TL, and the tip of the urostyle was bent at 45°. Forty days after hatching, individuals measured 18.5±0.93 mm in TL and were considered as juveniles as the number of fins became constant for each part. All the postflexion larvae had detached fins. Additionally, the melanophore was observed to be distributed on the head, centrum of the body, and dorsal fin, and there was a difference in the morphology from the water stream.

• Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.169-180
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• 2023

Oreochromis niloticus is the most ecologically and economically important fish in tropical and sub-tropical aquatic systems. Recently, due to sever anthropogenic stressors, hydrological variations and infestations of invasive alien species in Ethiopian water bodies, fish community structure and ecosystem of Lake Tana is changing alarmingly. So far, there is paucity of information on the morphometric relations and diet composition of O. niloticus in Lake Tana, gulf of Gorgora. A total of 309 fish samples were collected and their total length (TL), standard length (SL) and total weight (TW) were measured to determine morphometric relations; and gut contents were examined to identify most important food item in the diet of the fish. Results indicated that, the relation between TL and SL was significant (p < 0.001) and linear (SL = 0.942TL-2.41) while the relation between TL and TW was curvilinear (TW = 0.014 TL^2.8) indicating allometric growth. Among the total guts scrutinized, 53 (17.3%) of them were empty and the remaining 256 (82.7%) were non-empty. Phytoplankton constituted the largest bulk and occurred in 77% of the guts examined and volumetrically accounted 44.3%. Detritus and zooplankton had an intermediate importance by occurring 60.2% and 63.3% of all guts scrutinized and constituted about 25.6% and 15.5% of the total volume respectively. Contributions of macrophytes, insects, nematodes and unidentified food items were relatively low in their importance. Ontogenetic dietary shift was observed in the diet indicating an omnivorous feeding habit of the adult fish.

• Nuclear Engineering and Technology
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• v.56 no.6
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• pp.2113-2119
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• 2024

This study presents the development and characterization of a prototype TL/OSL reader for the retrospective dose assessment of individuals in radiological emergencies. The reader is portable, semi-automatic, and capable of accurate measurements. The dimension of the reader is 25 × 25 × 37 cm³ and the weight is about 15 kg. The reader consists of a sample moving stage, a heating module, an optical stimulation module, a detection module, a data acquisition (DAQ) unit, a nitrogen gas control module, and a PC with a GUI program. The reader has three measurement modes: TL, CW_OSL, and custom mode. The reader was characterized using commercial thermal luminescence dosimeters (TLD, LiF:Mg,Cu,Si) and optically stimulated dosimeters (OSLD, Al₂O₃:C), as well as fortuitous materials, such as display glasses and resistors of mobile phone. The results showed that the reader is capable of measuring signals with a detection limit of up to 0.02 mGy using a commercial dosimeter. In the dose recovery test using fortuitous materials, the reconstructed doses obtained three days post-irradiation closely aligned with the initially administered doses. As a result, this study suggests that the developed TL/OSL reader is a promising instrument for emergency dose assessment at accident sites.