• 보존과학회지
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• 제21권
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• pp.89-100
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• 2007

경상도지역의 두동리, 백련리, 사촌리 가마터 출토 백자편 총 47점에 대하연 중성자방사화분석으로 태토의 미량성분 함량을 측정하고 주성분분석(PCA)과 판별분석(LDA)으로 통계처리하여 가마터별 산지 및 특성을 분류해보았다. 주성분분석과 판별분석에서 이용한 미량성분은 17개(Ba, Ce, Co, Cr, Cs, Dy, Eu, Hf, La, Lu, Rb, Sc, Sm, Ta, Th, V, Yb) 원소이며, 분류에 기여한 원소는 6개(Dy, Sm, La, Ce, Lu, Sc) 원소로 확인된다. 가시적 특징에 따라 구분되는 연질과 경질백자는 미량성분의 화학적 조성이 유사하여 원료의 조성 차이가 없는 것으로 확인되나, 양질(I)과 조질백자(II)는 화학적 조성에 차이가 나타남에 따라 원료의 채취 장소나 수비와 첨가제 사용의 제작 과정에 차이가 있었을 것으로 판단된다.

• 한국환경과학회지
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• 제2권1호
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• pp.57-68
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• 1993

Polycyclic aromatic hydrocarbons (PAMs) are ubiquitous contaminants in marine environments. PAHs enter estuarine and nearshore marine environment via several routes such as combustion of fossil fuels, domestic and industrial effluents and oil spills PAHs have been the focus of numerous studies in the world because they owe potentially carcinogenic, mutagenic, and teratogenic to aquatic organisms and humans from consuming contaminated food. However, one can hardly find any available data on PAM content in marine organisms in Korea. The present study was carried out in order to determine PAH content in oysters from the intertidal and subtidal zones of Chinhae Bay, which is located in near urban communities and an industrial complex, and the bay is considered to be a major repositories of PAHs. 16 PAHs were analyzed by High Performance Liquid Chromatography (HPLC) with uv/vis and fluorescence detectors in oysters: they are naphthalene (NPTHL), acenaphthylene (ANCPL), acenaphthene (ACNPN), fluorene (FLURN), phenanthrene (PKEN), anthracene (ANTHR), fluoranthene (FLRTH), pyrene (PYRf), benzo(a)anthracene (BaA), chrysene (CHRY), benzo(b)- fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(a)pyrene (BaP), dibenz(a, h)anthracene (DhA), benzo(g, h, i)peryne (Bghip) and indeno(1, 2, 3, -cd)pyrene (I123cdP). The PAH contents in oysters from the intertidal and subtidal zones of Chinhae Bay ranged from < 0.1 to 992.0 $\mu\textrm{g}$/kg (mean 69.8 $\pm$ 9.8 $\mu\textrm{g}$/kg). Key words . polycyclic aromatic hydrocarbon, high performance liquid chromatography, oyster, Chinhae Bay.

• Journal of Electrical Engineering and Technology
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• 제4권4호
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• pp.527-530
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• 2009

$(Ba_{0.57}Sr_{0.33}Ca_{0.10})TiO_3$(=BSCT) powders, prepared by the sol-gel method, were doped using $MnCO_3$ as the acceptor and $Dy_2O_3$ as the donor. This powder was mixed with an organic vehicle. BSCT thick films were fabricated by the screen-printing techniques on the alumina substrate. The structural and dielectric properties of BSCT thick films were investigated with variation of the $Dy_2O_3$ amount. As a result of the differential thermal analysis (DTA), the exothermic peak was observed at around $670^{\circ}C$ due to the formation of the polycrystalline perovskite phase. All the BSCT thick films showed the XRD patterns of a typical polycrystalline perovskite structure. The average grain size of BSCT thick films decreased with an increasing amount of $Dy_2O_3$. The relative dielectric constant and dielectric loss of the BSCT thick film doped $Dy_2O_3$ 0.1mol% were 4637.4 and 1.6% at 1kHz, respectively.

• 농업과학연구
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• 제7권2호
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• pp.59-64
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• 1980

본(本) 실험(實驗)은 감자의 생장점배양시(生長點培養時) 기본배지(基本培地)에 첨가(添加)되는 2.4-D, NAA 및 Benzyladenine이 감자의 생장점(生長點)으로 부터의 기관(器官)의 분화(分化) 및 생장(生長)과 Callus의 유기(誘起)에 미치는 영향(影響)을 구명(究明)하여 기내배양(器內培養)을 이용(利用)한 감자 대량번식방안수립(大量繁殖方案樹立)을 위(爲)한 기초정보(基礎情報)를 얻고져 수행(遂行)하였던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. BA의 농도(濃度)가 증가(增加)됨에 따라 경(莖)의 신장(伸長)은 현저(顯著)히 촉진(促進)되었으나 BA를 첨가(添加)한 배지상(培地上)에서는 근(根) 및 Callus는 전혀 유기(誘起)되지 않았다. 2. 0.5mg/l 혹(或)은 그 이상(以上)의 NAA를 첨가(添加)한 배지상(培地上)에서는 경(莖)이 전혀 분화(分化)되지 않았고 공시개체전부(供試個體全部)에서 Callus만 유기(誘起)되었으며 Callus의 생장(生長)은 NAA의 농도(濃度)가 증가(增加)될 수록 현저(顯著)히 촉진(促進)되었다. 3. NAA를 0.1mg/l 이상(以上) 첨가(添加)한 배지상(培地上)에서는 약(約) 50% 이상(以上)의 개체(個體)에서 근(根)이 발생(發生)되었으나 2.4-D를 첨가(添加)한 배지상(培地上)에서는 전혀 근(根)의 발생(發生)이 없었다. 4. 1.0mg/l 이상(以上)의 2.4-D를 첨가(添加)한 배지상(培地上)에서는 경(莖)의 분화(分化)가 전혀 없었으며 2.4-D 0.1mg/l까지는 2.4-D의 농도(濃度)를 높일수록 경(莖)의 신장(伸長)은 촉진(促進)되었다. 5. Callus의 유기(誘起) 및 생장(生長)에는 2.4-D보다 NAA가 현저(顯著)히 효과적(效果的)이었고 2.0mg/l 첨가(添加)한 MS배지(培地)가 Callus의 유기(誘起) 및 생장(生長)에는 가장 적합(適合)하였다. 6. 식물체(植物體)의 재분화(再分化)에는 MS배지(培地)에 BA 2.0 및 NAA 0.1mg/l 혹(或)은 BA 1.0 및 2.4-D 0.1mg/l를 첨가(添加)한 배지(培地)가 가장 효과적(效果的)이었다.

• 농업과학연구
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• 제20권2호
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• pp.133-144
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• 1993

본(本) 연구(硏究)는 Agrobacterium tumefaciens을 binary vector system(C' 121, A' 121, L' 121)의 방법(方法)으로 처리(處理)하여 감자(Solanum tuberosum cv. Sumi)의 일반종서(一般種薯), microtuber 및 엽육조직(葉肉組織)과 줄기조직(組織)의 형질전환(形質轉換)을 유기(誘起)하기 위한 실험(實驗)을 수행(修行)하였다. Binary vector의 transconjugant는 triparental mating method에 의해 작성(作成)하였고, 이에 의해 만들어진 C'121, A' 121 및 L' 121을 cocultivation 처리방법(處理方法)으로 감자조직(組織)의 절편(切片)에 접종처리(接種處理)하고, cytokinin과 auxin을 여러 가지 농도(濃度)로 조합(組合)하여 첨가(添加)한 MS배지(培地)에서 배양(培養)한 결과(結果) C' 121과 A' 121 접종구(接種區)에서는 BA, NAA 및 2.4-D 복합처리시(複合處理時) NAA보다는 2,4-D의 농도(濃度)가 높아짐에 따라 callus의 분화(分化)가 증가(增加)되었고, 일반종서(一般種薯)에서의 callus는 쉽게 갈변(褐變)하여 증식(增殖)이 잘 되지 않았다. 또한, L' 121의 접중구(接種區)에서는 microtuber나 일반종서(一般種薯)에서도 거의 callus 형성(形成)되지 않았다. 2,4-D 단용처리시(單用處理時) C' 121과 A' 121 모두 높은 callus 분화율(分化率)을 나타냈지만 NAA 단용처리시(單用處理時)에는 2,4-D보다는 저조(低調)한 callus분화(分化)를 보였다. 2iP를 BA 대신(代身) 사용(使用)하였을 경우(境遇) L' 121에서도 높은 callus 분화율(分化率)을 보였고, callus의 증식(增殖)도 잘 이루어졌다. BA 1mg/l+NAA 0.01mg/l+Zeatin 0.5mg/l처리구(處理區)에서의 callus를 BA 2mg/l+2,4-D 1mg/l의 MS배지(培地)에 계대배양(繼代培養)한 결과(結果) embryo 및 shoot가 형성(形成)되었다. 기내배양(器內培養)한 엽육조직(葉肉組織)과 줄기조직(組織)은 Zeatin 2mg/l+NAA 0.01mg/l+GA 0.1mg/l혼합(混合) 처리구(處理區)에서 세가지 conjugants 모두에서 비교적(比較的) 높은 callus 형성율(形成率)을 보였다. 각 처리구(處理區)에서 얻어진 callus는 계대배양(繼代培養)에 의해 현재(現在)도 생육(生育)이 왕성(旺盛)하게 이루어지고 있어 빠르고, 효율적(效率的)인 식물체(植物體) 분화(分化)에 관한 연구(硏究)가 계속 수행(修行)되어질 것이다.

• Smart Structures and Systems
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• 제22권3호
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• pp.259-276
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• 2018

This paper studies the energies and energy release rate (ERR) for the initially rotationally symmetric compressed (or stretched) in the inward (outward) radial direction of the PZT/Elastic/PZT sandwich circular plate with interface penny-shaped cracks. The investigations are made by utilizing the so-called three-dimensional linearized field equations and relations of electro-elasticity for piezoelectric materials. The quantities related to the initial stress state are determined within the scope of the classical linear theory of piezoelectricity. Mathematical formulation of the corresponding problem and determination of the quantities related to the stress-strain state which appear as a result of the action of the uniformly normal additional opening forces acting on the penny-shaped crack's edges are made within the scope of the aforementioned three-dimensional linearized field equations solution which is obtained with the use of the FEM modelling. Numerical results of the energies and ERR and the influence of the problem parameters on these quantities are presented and discussed for the PZT- 5H/Al/PZT-5H, PZT-4/Al/PZT-4, $BaTiO_3/Al/BaTiO_3$ and PZT-5H/StPZT-5H sandwich plates. In particular, it is established that the magnitude of the influence of the piezoelectricity and initial loading on the ERR increases with crack radius length.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.263-266
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• 2001

In this paper, we investigated dielectric properies for BST thin films that was deposited on MgO/Si substrates using RF magnetron sputtering. In here, MgO film was used to perform that a diffusion b arrier between the BST film and Si substrate and a buffer layer to assist the BST film growth. A d eposition condition for MgO films was RF Power of 50W, substrate temperature of room temperature and the working gas ratio of Ar:O$_2$ were varied from 90:10 to 60:47. Finally we manufactured the cap acitor of Al/BST/MgO/Si/Al structure to know electrical properties of this capacitor through I-V, C-V measurement. In the results, C-V aha racteristic curves was shown a ferroelectric property so we measured P-E. A remanent poliazation and coerceive electric field was present 2$\mu$C/cm$^2$ and -27kV/cm respectively at Ar:O$_2$=90:10. And a va clue of dielectric constant was 86 at Ar:02=90:10.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2011년도 임시총회 및 하계학술연구발표회
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• pp.7-8
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• 2011

Basically, the lattice mismatch between film and substrate can make those BiFeO3(BFO) films distorted with strain structure. BFO phase can be stabilized on LaAlO3(LAO) represents the example of a multiferroic with giant axial ratio. Its crystal structure is not strictly tetragonal, but tetragonal with a slight monoclinic distortion and related to the rotation of the oxygen octahedra. In this study, we show that phases with a tetragonal-like epitaxial BFO films can indeed be ferroelectric and also can be stabilized via epitaxial growth onto LAO. Recent reports on epitaxial BFO films show that the crystal structure changes from nearly rhombohedral ("R-like") to nearly tetragonal("T-like") at strains exceeding approximately -4.5%, with the "T-like" structure being characterized by a highly enhanced c/a ratio. While both the "R-like" and the "T-like" phases are monoclinic, our detailed x-ray diffraction results reveal asymmetry change from MA and MC type, respectively. By applying additional strain or by modifying the unit cell volume of the film by substituting Ba for Bi, the monoclinic distortion in the "T-like" MC phase is reduced, i.e. the system approaches a true tetragonal symmetry. There are two different M-H loops for $Bi_{1-x}Ba_xFeO_{3-{\delta}}$(BBFO) and BFO films on SrTiO3(STO) & LAO substrates. Along with the ferroelectric characterization, these magnetic data indicate that the BFO phase stabilized on LAO represents the first example of a multiferroic with giant axial ratio. However, there is a significant difference between this phase and other predicted ferroelectrics with a giant axial ratio: its crystal structure is not strictly tetragonal, but tetragonal with a slight monoclinic distortion. Therefore, in going from bulk to highly-strained films, a phase sequence of rhombohedral(R)-to-monoclinic ["R-like" MA-to-monoclinic, "T-like" MC-to-tetragonal (T)] is observed. This sequence is otherwise seen only near morphotropic phase boundaries in lead-based solid-solution perovskites (i.e. near a compositionally induced phase instability), where it can be controlled by electric field, temperature, or composition. Our results show that this evolution can occur in a lead-free, stoichiometric material and can be induced by stress alone. Those major results are summarized as follows ; 1) Ba-doping increases the unit cell volume, 2) BBFO on LAO can be fully strained up to x=0.08 as a strain limit (Fig. 1), 3) P(E) & M(H) properties can be tuned by the variation of composition, strain, and film thickness.

• 복식문화연구
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• 제24권5호
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• pp.697-708
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• 2016

The term used to describe consumer's valuation of a brand is brand equity. One concept that can be managed and may impact valuation of a prestige brand is "luxuriousness." As the concept of "luxuriousness" appears to be a key factor contributing to the equity of a prestige brand, the purpose of this study was to examine how luxuriousness is related to the brand equity utilizing a model developed by Yoo, Donthu, and Lee (2000). Yoo et al. (2000) identified three dimensions [brand association with awareness (BA), perceived quality (PQ), brand loyalty (BL)] accounted for the equity (OBE) of a brand. We speculated that the five dimensions of luxuriousness (i.e., quality, extended self, hedonism, accessibility, and tradition) would selectively influence the two dimensions of brand equity (BA, PQ) and that loyalty would mediate the relationship between the two dimensions of brand equity (BA, PQ) and overall brand equity. A total of 502 participants aged from 18 to 74 were surveyed in USA. Using AMOS 18, the path analysis was conducted with the maximum-likelihood estimation procedure. The model exhibited a good fit with the data and all hypotheses were supported except one. Quality, accessibility, and hedonism dimensions of luxuriousness affected perceived quality of the equity of a brand. Hedonism and extended self dimensions affected brand association with awareness. However, tradition dimension did not significantly influence brand association with awareness. Overall, this research expands understanding of brand equity as it documents the contributions of luxuriousness, a component that can be controlled by brand managers.

• Nuclear Engineering and Technology
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• 제51권8호
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• pp.2005-2012
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• 2019

This work investigated the radiation attenuation characteristics of three series of tellurite glass systems with the following compositions: 30PbO-10ZnO-xTeO₂-(60-x)B₂O₃ where x = 10, 30, 40, 50 and 60 mol%, xBaO-xB₂O₃-(100-2x)TeO₂ with x = 15-40 mol% and 50ZnO-(50-x)P₂O₅-xTeO₂, where x = 0, 10, .40 mol%. The results revealed that the attenuation parameters in all the samples decrease with increase in the energy, which implied that all the samples have better interaction with gamma photons at low energies and thus higher photon attenuating efficiency. From the three systems, the samples coded as PbZnBTe60, BaBTe70 and ZnPTe40 have the lowest half value layer values and accordingly have superior photon attenuation efficacy. The maximum effective atomic number values were found for energy less than 0.1 MeV particularly near the K-edges absorption of the heavy atomic number elements such as Te, Ba and Pb. At the lowest energy, the Z_eff values are found in the range of 62.33-66.25, 49.43-50.81 and 24.99-35.83 for series 1-3 respectively. Also, we found that the density of the glass remarkably affects the photon attenuation ability of the selected glasses. The mean free path results showed that the PbO-ZnO-TeO₂-B₂O₃ glass system has better radiation shielding efficiency than the glass samples in series 2 and 3.