• Title/Summary/Keyword: Sn

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Distribution of Radionuclide Labeled Liposome in Experimental Study (방사성동위원소표지 Liposome의 분포에 대한 실험적 연구)

  • Lee, Bum-Woo;Jeong, Jae-Min;Kim, Sang-Eun;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon;Ha, Sung-Whan
    • The Korean Journal of Nuclear Medicine
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    • v.24 no.2
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    • pp.317-324
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    • 1990
  • Liposome was labelled with $^{99m}Tc$ after negative charged liposome was formed with combination of a few lipid components. $^{99m}Tc$ liposome was injected through the tail vein of C3H mice bearing fibrosarcoma and biodistribution of $^{99m}Tc$ liposome was evaluated. The results were as follows: 1) We confirmed formation of liposome which was small unillamellar and multilamellar vesicles. 2) In this experiment the optimal concentration of $SnCl_2$ was $156{\mu}g/ml$ to label liposome with $^{99m}Tc$ and labelling efficiency was 95%. 3) The labelled liposome was stable when it was incubated with human serum for 24 hours. Mean labelling efficiency was 94% at 24 hour. 4) The main uptake sites of Tc-99m liposome were liver and spleen. It showed significantly higher uptake than $^{99m}Tc$ HSA (p < 0.001). 5) $^{99m}Tc$ liposome uptake in tumor tissue was not significantly higher than $^{99m}Tc$ HSA uptake. In conclusion, $^{99m}Tc$ liposome disclosed high labelling efficiency and was highly stable. Liver and spleen were main uptake sites of $^{99m}Tc$ liposome. The uptake mechanism of $^{99m}Tc$ liposome also seemed to be different from that of $^{99m}Tc$ HSA. We conclude that $^{99m}Tc$ liposome would be a promising agents for the imaging of some tumor.

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Expression of Human p53 Gene as Glutathione S-transferase Fusion Proteins in Escherichia coli (사람의 p53 유전자와 Glutathione S-Transferase와의 융합 단백질의 대장균에서의 발현)

  • 오상진
    • Korean Journal of Microbiology
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    • v.31 no.4
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    • pp.279-285
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    • 1993
  • Alterations of the p53 gene arc among the most frequent genetic changes in human cancer and often result in increased levels of p53 protein within the malignant cells. Detection of accumulated p53 protein can be a useful prognostic tool in human cancer. In order to make polyclonal antibodies for immunohistochemical screening. human p53 gene was expressed in E. coli in the form of GST (glutathione S-transfi.:rase) fusion proteins. Two p53 gene fragments. which were N('()I small fragment encoding amino acid residues of 1-151-: and Ncol large fragment of 159-393. were subeloned into the unique BamHI site present within the pGEX-2T vector using BamHI linker and recombinant plasmids pGTNS and pGTNL were constructed. respectively. The p53 cDNA fragment (from pC53-$SN_3$,) encoding amino acid 38-145 (proline at residue 72) was amplified by polymerase chain reaction(PCR). The amplified DNA was digested with BamHI and Prull and inserted into the BamHI-Smal sites of pG EX-2T and recombinant plasmid pGTBP was constructed. After IPTG induction of these plasmids for 4 hours. fusion proteins were purified from E. coli extracts with glutathione Sepharose beads. The bound proteins were resolved by 10% SDS-polyacrylamide gel electrophoresis and the molecular weights were 54 kDa. 53 kDa and 40 kDa. respectively. Approximately one milligram of fusion proteins were purified from 1 -liter cultures.

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Gilt-bronze Standing Avalokiteshvara from Gyuam-ri, Buyeo: The Structure and Production Technique (부여 규암리 출토 금동관음보살 입상의 형상과 제작기법)

  • Shin, Yongbi;Kim, Jiho
    • Conservation Science in Museum
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    • v.23
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    • pp.1-16
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    • 2020
  • In this paper, Gilt-bronze Standing Avaolkiteshvara (National Treasure No. 293, M355) excavated at Gyuam-ri in Buyeo was observed with a microscope to identify the production technique applied to it. It was also analyzed with XRF and hard X-ray to identify the composition and the surface treatment techniques and casting method applied. In this statue, Avalokiteshvara is standing upright on a lotus pedestal. The lotus designs on the pedestal and those on the shawl flowing down on both sides of the statue are characteristic of Buddhist statues from the seventh century or later. The use of supports to affix the outer and inner molds and traces of injected cast were observed in the interior of the pedestal. The blisters on the arms and pedestal created during the bronze casting indicate the use of lost-wax casting, which was popularly employed for the production of mid- or small-sized gilt-bronze Buddhist statues in ancient times. The composition analysis identified a copper-tin-lead ternary alloy in the interior of the statue that was conventional used in the sixth and seventh centuries. It is likely that this simple alloy was used to facilitate casting and produce clearer expressions of designs and ornaments on the statue. Mercury (Hg) was detected on the surface of the statue, indicating the use of amalgam-plating with gold (Au) dissolved in mercury. This plating method is a common surface treatment technique used for small gilt-bronze statutes in ancient Korea.

Quantitative Analysis and Archaeometric Interpretation for Molten Glass and Bronze Materials within Baekje Crucibles from the Ssangbukri Site in Buyeo, Korea (부여 쌍북리유적 출토 백제 도가니 내부 유리 및 청동 용융물질의 정량분석과 고고과학적 해석)

  • Lee, Chan-Hee;Park, Jin-Young;Kim, Ji-Young
    • Journal of Conservation Science
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    • v.26 no.2
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    • pp.157-169
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    • 2010
  • This study focused on the material characteristics and archaeometric relationship between the molten glass and bronze materials within the crucibles and gilt-bronze Bodhisattva statue excavated from the Ssangbukri site in Buyeo, Korea. Yellowish green to red brown vitreous material in the crucibles was identified as lead glass which contained scarce amount of BaO, and low $Al_2O_3$ and CaO. Metallic molten material was identified as bronze of copper-tin-lead alloy with low amount of impurities that indicated well-refined materials. Also, cassiterite was used for raw metal ore of tin. The Bodhisattva statue consisted of major copper with trace impurities in the core metal, and gold amalgam in the gilded layer. Though lead isotopic analysis showed contradictory results in each lead glass, bronze and Bodhisattva statue that required further examination, it could be stated that the statue was made in the Ssangbukri site based on the high-level technical skills of bronze production.

Geochemistry of Stable Isotope and Mineralization Age of Magnetite Deposits from the Janggun Mine, Korea (장군광산(將軍鑛山) 자철광상(磁鐵鑛床)의 광화시기(鑛化時期) 및 안정동위원소(安定同位元素) 지화학(地化學))

  • Lee, Hyun Koo;Lee, Chan Hee;Kim, Sang Jung
    • Economic and Environmental Geology
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    • v.29 no.4
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    • pp.411-419
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    • 1996
  • The Janggun magnetite deposits occur as the lens-shaped magnesian skarn, magnetite and base-metal sulfide orebodies developed in the Cambrian Janggun Limestone Formation. The K-Ar age of alteration sericite indicates that the mineralization took place during late Cretaceous age (107 to 70 Ma). The ore deposition is divided into two stages as a early skarn and late hydrothermal stage. Mineralogy of skara stage (107 Ma) consists of iron oxide, base-metal sulfides, Mg-Fe carbonates and some Mg- and Ca-skarn minerals, and those of the hydrothermal stage (70 Ma) is deposited base-metal sulfides, some Sb- and Sn-sulfosalts, and native bismuth. Based on mineral assemblages, chemical compositions and thermodynamic considerations, the formation temperature, $-logfs_2$, $-logfo_2$ and pH of ore fluids progressively decreased and/or increased with time from skarn stage (433 to $345^{\circ}C$, 8.8 to 9.9 atm, 29.4 to 31.6 atm, and 6.1 to 7.2) to hydrothermal stage (245 to $315^{\circ}C$, 11.2 to 12.3 atm, 33.6 to 35.4 atm, and 7.3 to 7.8). The ${\delta}^{34}S$ values of sulfides have a wide range between 3.2 to 11.6‰. The calculated ${\delta}^{34}S_{H_2S}$ values of ore fluids are relatively homo-geneous as 2.9 to 5.4‰ (skam stage) and 8.7 to 13.5‰ (hydrothermal stage), which are a deep-seated igneous source of sulfur indicates progressive increasing due to the mixing of oxidized sedimentary sulfur with increasing paragenetic time. The ${\delta}^{13}C$ values of carbonates in ores range from -4.6 to -2.5‰. Oxygen and hydrogen isotope data revealed that the ${\delta}^{38}O_{H_2O}$ and ${\delta}D$ values of ore fluids decreased gradually with time from 14.7 to 1.8‰ and -85 to -73‰ (skarn stage), and from 11.1 to -0.2‰ and -87 to -80‰ (hydrothermal stage), respectively. This indicates that magmatic water was dominant during the early skarn mineralization but was progressively replaced by meteoric water during the later hydrothermal replacement.

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Seasonal Variations in the Nutritional Compositions and Heavy Metals in Two Demersal Fish, Liparis tessellatus (Cubed Snailfish) and Hemitripterus villosus (Shaggy Sea Raven) (동해안 저서어 곰치와 풍덕구이의 영양성분 및 중금속의 계절적 변화)

  • Lee, Byung-Yong;Surh, Jeong-Hee
    • Korean Journal of Food Science and Technology
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    • v.43 no.3
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    • pp.282-290
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    • 2011
  • Two species of demersal fish, Liparis tessellates (cubed snailfish) and Hemitripterus villosus (shaggy sea raven), were investigated in relation to seasonal chemical composition. Total fat contents of the two fish were very low and were not appreciably different throughout the year, whereas their fatty acid compositions were significantly different depending on season. Noticeable changes in the moisture and protein contents in the two fishes were observed before and after spawning. Cubed snailfish showed relatively high amounts of total amino acids and free amino acids during summer months, whereas the levels of those in shaggy sea raven remained relatively unchanged throughout the year. Regardless of season, the major fatty acid of the two fishes was palmitic acid and most of polyunsaturated fatty acids (PUFAs) were n-3 PUFAs. Lead was over the legislative limit in some samples of the two fishes.

Emergence of Social Networked Journalism Model: A Case Study of Social News Site, "wikitree" (소셜 네트워크 저널리즘 모델의 출현: 소셜 뉴스사이트, "위키트리" 사례연구)

  • Seol, Jinah
    • Journal of Internet Computing and Services
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    • v.16 no.1
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    • pp.83-90
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    • 2015
  • This paper examines the rising value of social networked journalism and analyzes the case of a social news site based on the theory of networked journalism. Social networked journalism allows the public to be involved in every aspect of journalism production through crowd-sourcing and interactivity. The networking effect with the public is driving journalism to transform into a more open, more networked and more responsive venue. "wikitree" is a social networking news service on which anybody can write news and disseminate it via Facebook and Twitter. It is operated as an open sourced program which incorporates "Google Translate" to automatically convert all its content, enabling any global citizen with an Internet access to contribute news production and share either their own creative contents or generated contents from other sources. Since its inception, "wikitree global" site has been expanding its coverage rapidly with access points arising from 160 countries. Analyzing its international coverage by country and by news category as well as by the unique visit numbers via SNS, the results of the case study imply that networking with the global public can enhance news traffic to the social news site as well as to specific news items. The results also suggest that the utilization of Twitter and Facebook in social networked journalism can break the boundary between local and global public by extending news-gathering ability while growing audience's interest in the site, and engender a feasible business model for a local online journalism.

Cu Electroplating on the Si Wafer and Reliability Assessment of Low Alpha Solder Bump for 3-D Packaging (3차원 실장용 실리콘 웨이퍼 Cu 전해도금 및 로우알파솔더 범프의 신뢰성 평가)

  • Jung, Do Hyun;Lee, Joon Hyung;Jung, Jae Pil
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2012.11a
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    • pp.123-123
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    • 2012
  • 최근 연구되고 있는 TSV(Through Silicon Via) 기술은 Si 웨이퍼 상에 직접 전기적 연결 통로인 관통홀을 형성하는 방법으로 칩간 연결거리를 최소화 할 수 있으며, 부피의 감소, 연결부 단축에 따른 빠른 신호 전달을 가능하게 한다. 이러한 TSV 기술은 최근의 초경량화와 고집적화로 대표되는 전자제품의 요구를 만족시킬 수 있는 차세대 실장법으로 기대를 모으고 있다. 한편, 납땜 재료의 주 원료인 주석은 주로 반도체 소자의 제조, 반도체 칩과 기판의 접합 및 플립 칩 (Flip Chip) 제조시의 범프 형성 등 반도체용 배선재료에 널리 사용되고 있다. 최근에는 납의 유해성 때문에 대부분의 전자제품은 무연솔더를 이용하여 제조되고 있지만, 주석을 이용한 반도체 소자가 고밀도화, 고 용량화 및 미세피치(Fine Pitch)화 되고 있기 때문에, 반도체 칩의 근방에 배치된 주석으로부터 많은 알파 방사선이 방출되어 메모리 셀의 정보를 유실시키는 소프트 에러 (Soft Error)가 발생되는 위험이 많아지고 있다. 이로 인해, 반도체 소자 및 납땜 재료의 주 원료인 주석의 고순도화가 요구되고 있으며, 특히 알파 방사선의 방출이 낮은 로우알파솔더 (Low Alpha Solder)가 요구되고 있다. 이에 따라 본 연구는 4인치 실리콘 웨이퍼상에 직경 $60{\mu}m$, 깊이 $120{\mu}m$의 비아홀을 형성하고, 비아 홀 내에 기능 박막증착 및 전해도금을 이용하여 전도성 물질인 Cu를 충전한 후 직경 $80{\mu}m$의 로우알파 Sn-1.0Ag-0.5Cu 솔더를 접합 한 후, 접합부 신뢰성 평가를 수행을 위해 고속 전단시험을 실시하였다. 비아 홀 내 미세구조와 범프의 형상 및 전단시험 후 파괴모드의 분석은 FE-SEM (Field Emission Scanning Electron Microscope)을 이용하여 관찰하였다. 연구 결과 비아의 입구 막힘이나 보이드(Void)와 같은 결함 없이 Cu를 충전하였으며, 고속전단의 경우는 전단 속도가 증가할수록 취성파괴가 증가하는 경향을 보였다. 본 연구를 통하여 전해도금을 이용한 비아 홀 내 Cu의 고속 충전 및 로우알파 솔더 볼의 범프 형성이 가능하였으며, 이로 인한 전자제품의 소프트에러의 감소가 기대된다.

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Relative Importance and Priority of Evaluation Elements in University Department Homepage Selection Process -with Special Reference to College Prep Students in Busan- (대학 학과홈페이지의 평가요소에 대한 상대적 중요도 분석 -부산지역 수험생들의 인식을 중심으로-)

  • Kang, Kyoung-Soo;Lee, Young-Woo;Lee, Kang-Hyuk;Lee, Young-Sook
    • The Journal of the Korea Contents Association
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    • v.15 no.3
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    • pp.488-498
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    • 2015
  • Form the observation that the successful management and operation of university websites brings about university branding effects, this paper attempts to identify the problems in relation to evaluation elements of university homepages and establish a new evaluation model that allows us to grasp the importance and priority of phased evaluation elements. In particular, we tried to secure the objectivity of the importance of department homepage evaluation elements by using AHP(Analytic Hierarchy Process). Our analysis shows that among 29 evaluation elements of department homepage, mobile service, curriculum, description of department's characteristics, guide to homepage usage/accessibility to site map and differentiated educational method were considered to be relatively important whereas the relative importance of department's slogan, differentiated image and identity, linkage to SNS, Q&A bulletin board, operation of department community, and FAQ was low. Based on the findings from our analysis, we present the basic foundation for successful management and operation of university department homepages along with a few suggestions for vitalizing those hompages.

A Study on Deketalization of Rigid ${\beta}$-Aminoketones (형태가 고정된 ${\beta}$-아미노케톤의 탈케탈화 (반응) 의 연구)

  • Jack C. Kim;Yong Tae Lee;Ung Chan Yoon;In-Seop Cho;Sung Hwan Moon;Sun Hong Han
    • Journal of the Korean Chemical Society
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    • v.32 no.6
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    • pp.557-566
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    • 1988
  • The causes of failure in the deketalization of rigid ${\beta}$-aminoketals were separately investigated by examining the deketalization of 3 ketals, 2-ethylenedioxy-l-acenaphthenylamine (2), N-(2-ethylenedioxy-l-acenaphthenyl)acetamide(13) and trimethyl-2-ethylenedioxy-1-acenaphthenylammonium iodide(14), and by examining the deketalization of non-rigid ${\beta}$-aminoketal, 2-amino-l-ethylenedioxyacetophenone(19) and non-rigid aliphatic acetals, dimethylaminoformaldehyde dimethylacetal (20) and 2-aminoactaldehyde dimethyl acetal(21). While compounds 2 and 14 were not able to be hydrolyzed in the various acidic conditions 13 was easily deketalized. The result indicated the importance of electrostatic repulsion in the possible dicationic intermediates as a factor of failure in the deketalization. The observations of easy deketalization of compounds 19, 20 and 21 indicated that the structural characters of rigid $\beta-aminoketals$ are also important factors in the hydrolysis of ${\beta}$-aminoketals.

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