• Food Science and Biotechnology
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• 제18권4호
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• pp.1022-1026
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• 2009

Cross contamination of foodborne virus via food utensils can be an important route of virus propagation. Bacteriophage MS2 was used as a surrogate for norovirus. The viability loss of bacteriophage MS2 attached to 4 kinds of metal surfaces was investigated at different temperatures and relative humidities (RH). The rate of viability loss was higher at $22^{\circ}C$ than at $10^{\circ}C$ and was higher at 75% RH than at 40% RH. The viability loss of the virus attached to copper or bronze surface was faster than on stainless steel or tin surface. Also the beef juice applied with the virus inoculum on the metal surfaces lowered the rate of viability loss. Although bronze was not as effective as copper in resulting the viability loss, it has been extensively used as a traditional Korean kitchen utensil and could be used more widely to decrease the viral poisoning at food processing environment and hospitals.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.248-249
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• 2005

The tungsten bronze type of strontium barium niobate(SBN) thin film was synthesized by metal organic decomposion method for SBN stock solution and the SBN thin film process were deposited by spin-coating process on Pt-deposited si-wafer(100) by magnetron sputtering system. The thickness of SBN thin film was 150$\sim$200 nm and were optimized for rpm of spin-coater system. The structural variation of SBN thin film was studied by TG-DTA and XRD. The deposited SBN stock solution on annealing at $400\sim800^{\circ}C$ a pure tungsten bronze SBN phase and the corresponding average grain size about 500$\sim$1000 nm influenced by annealing temperature.

• Tribology and Lubricants
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• 제4권1호
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• pp.56-68
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• 1988

The wear resistance of P-bronze which is widely used as worm gear material was investigated. In order 1o study the effect of additional elements on the wear resistance of Pbronze, the applied load and sliding time were selected as variables, and SCM4, were used as against metal. The addition of Fe improve wear resistance, for it precipities hard Fe$_3$ P phase and the work hardening coefficients are lowered due to decreasing solubility of P. When Fe is added in conventional P-bronze, the alloy is rather sliding than forming wear debris by frictional force during wear test. Experimental results indicated that the wear mechanisms for P-bronze are mainly consisted of abrasive wear due to Beilby layer forming mechanism and adhesive wear due to thermally activated wear mechanism. Moreover, the weight loss is decreased in accordance with increasing load and time. However the rate of wear loss is decreased as the sliding time is increased.

• 보존과학회지
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• 제37권4호
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• pp.340-356
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• 2021

We have tried the experimental research of lost-wax casting to reconstruct Gilt-Bronze Pensive Bodhisattva; preliminary and reconstruction experiment based on ancient texts. Main object to reconstruct is Korean National Treasure No.83, Gilt-Bronze Pensive Bodhisattva (Maitreya), then we measure alloy ratio and casting method based on the scientific analysis. Other impurities were removed from the base metal components(copper : tin : lead) and their ratio was set to 95.5 : 6.5 : 3 where the ratios for tin and lead were increased by 2.5% each. The piece-mold casting method was used, and piece-mold casting experiments were carried out twice in this study but supplementary research on piece-mold casting was necessary. The microstructure was confirmed to be typical cast microstructure and the component analysis result was similar to that of the prior study. Analysis of the chemical composition is confirmed to copper, tin, lead, and zinc, and the chemical composition of the matrix was 87.8%Cu-7.5%Sn-2.7%Pb-2.1%Zn, and similar to previous experimental research. Also resulted in the detection of small impurity in Zn. Analysis of the mould revealed that the mould was fabricated by adding quartz and organic matter for structural stability, fire resistance, and air permeability. We expect that our research will contribute to provide base data for advanced researches in future.

• 대한금속재료학회지
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• 제46권1호
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• pp.26-32
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• 2008

Examination of two bronze vessels supposedly from the Koryo dynasty revealed that they consist of bowls and stands that are fixed together using rivet joints made of Cu-Ag alloys. The bowls and stands were forged out of unleaded bronze alloys of approximately 22 weight % Sn before being quenched from the ${\alpha}+{\beta}$ region of the Cu-Sn phase diagram. This specific alloy and the thermo-mechanical treatment constitute two key elements of the unique technical tradition called Bangcha (방짜) that has long been established in Korea. The high Sn content ensures better casting and the thermal treatment causes the brittle ${\delta}$ phase to be avoided in forging as well as in services. The experiment on the laboratory Cu-Ag alloys of varying Ag contents suggested that the Cu-Ag system was the best choice of materials for the rivets at the time in view of their color, availability, ductility and low melting points.

• 분석과학
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• 제22권3호
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• pp.263-271
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• 2009

문화재 보존처리의 목적은 훼손된 원형을 되찾아주고, 부식을 억제함으로써 문화재를 오래도록 보존하는 것이다. 현재 많이 사용하는 청동유물 보존처리용 강화처리제 4종을 선별하여 코팅 특성을 조사하였으며 코팅 표면 관찰, 박막 두께, 접착력, 접촉각 및 표면에너지 등을 측정하였다. 또한 코팅의 변색과 노화 정도를 알아보기 위해 황변실험과 박막의 임피던스를 측정하였다. 그 결과, 수지 B와 수지 V가 우수한 코팅 특성을 보였다. 그러나 강화처리의 목적에 맞는 평가 요소는 수지와 시편간의 접착력과 황변에 대한 안정성 및 방식 성능이므로 수지 B가 현재 사용하는 4종의 강화처리제 중에서 강화처리의 목적에 가장 적합한 효과를 보여주었다.

• 전기학회논문지P
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• 제55권3호
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• pp.146-152
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• 2006

In order to analyze the characteristics of series arcs that could happen in poor connections of electrical facilities, we made an apparatus which is similar to actual situation. series arcs are generated between copper and copper, copper and bronze, copper and brass, bronze and bronze, and then oxidation growth and voltage waveform were measured. A very small vibration with constant movement is needed to grow oxidation initially, whereas oxidation growth proceeded without a vibration after a certain amount of time. At first, blue white flame was generated initially between copper and copper, and then yellow flame was generated. In case of contact between copper and copper, the length of oxidation growth was about 7.1[mm] in 90[min]. In case of contact between copper and brass, the length of oxidation growth was about 4.3[mm] in 90[min], When bronze is contacted with copper, the lengths of oxidation growth were about 1.4[mm] in 20[min] and 2.7[mm] in 40[min] respectively, and no more oxidation growth was shown after that. In case of contact between brass and brass, the length of oxidation growth was about 1.2[mm] in 90[min], so it was the smallest compared to other cases. When copper is contacted with copper, the current through the load was about 1.6[A] and the power dissipation increased from 19[W] to 31[W]. In case of oxidation growth between copper and brass, the voltage changed from 8.4[V] to 11[V]. However, the voltage drop and the power dissipation between copper and brass were small compared to oxidation growth between copper and copper. When series arcs were generated between bronze and copper, a peak was shown at the beginning of voltage increase, and 40[min] later, oxidation material was not grown any longer. When oxidation growth occurred, voltage waveform showed irregular waveforms with tiny ripples.

• 복식
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• 제57권1호
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• pp.93-104
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• 2007

This study is considered about the fabrics culture of Baekje Period by analyzing the fabrics pieces at a inner part of the It-bronze shoes found at the tomb of King Mu-ryeong in 1971 AD. The analysis methods of the fabrics pieces are a photographing of fabrics pieces surface by VMS, Digital camera(Nikon Coolpix 995) and the analysis of samples by SEM, XRD and FT-IR. It is assumed this fabrics pieces are the inner shoes, which consisted of compound woven silk at outward, some of tabby and a hemp at inward and the braids for decoration, of the gilt-bronze shoes. The features are as follows. 1. All of compound woven silk are the warp-faced compound tabby of plain fabrics and the density is various from high to low one. Compound woven silk which is attached the gilt-bronze shoes of the tomb of King Mu-ryeong weaves in high density by a thick thread. The fibers material of compound woven silk prove to be a silk by the analysis of wrap samples by SEM, XRD and FT-IR. 2. Tabby are excavated under the condition which attached on reverse side of compound woven silk. Those ran classify two types. First, the fine weaving by high density of wrap and weft. Second, the loose warp weaving with one warp and some of weft. 3. Hemp is almost ramie by SEM analysis and the density is different. Ramie which supposed to be attached Guem has the very low density. In addition to, Ramie pieces, excavated in condition and weaved finely, proved the conspicuous weaving skill in Baekje period. 4. Various kinds of braid are found and these ones classifies by fiber material and entwining way. Two types out of these are the one of silk thread, decorates the upper, middle parts of compound woven silk shoes and the other of hemp thread, decorates the lower parts.

• 박물관보존과학
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• 제20권
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• pp.49-60
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• 2018

대구 칠곡지구 일대 유적은 청동기시대 및 삼국시대 대규모 취락지가 확인된 고고학적 조사로 그 의의가 크다. 특히 대구 동천동 취락유적에서는 청동기시대 수혈주거지, 고상건물지, 석관묘, 우물, 집수기, 집석, 구상유구, 경작지, 환호, 하도 등의 유구가 확인되어 청동기시대 당시 취락의 전모를 알 수 있는 많은 자료가 조사되었다. 본 조사는 대구 동천동 취락유적 내 청동기시대 하도 유구 출토 목기 8점에 대한 수종분석 결과이다. 조사 결과, 침엽수재 수종인 소나무류(Pinus spp.)가 2점, 전나무속(Abies spp.) 수종이 2점, 활엽수재 수종인 상수리나무류(Quercus sp.)가 4점 식별되었다. 용도미상으로 분류된 3점의 목기는 소나무류와 전나무속 수종이였으며, 건축부재 5점은 소나무류가 1점, 상수리나무류가 4점이었다.

• 박물관보존과학
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• 제16권
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• pp.32-45
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• 2015

청동현향로(靑銅懸香爐)는 1971년 경기도 하남시 춘궁동에서 발견된 고려시대의 향로이다. 유물의 표면에는 점토가 두껍게 고착되어 있으며, 부식으로 인해 청동병과 다수의 균열이 존재하고 일부분이 결손되어 취약한 상태였다. 청동현향로의 안정한 보존과 전시를 위해 표면에 고착된 이물질을 제거하고 취약한 재질을 강화하였고, 균열부위와 결손부위는 직조유리섬유로 보강하고 에폭시 수지로 복원하였다. 제작기술을 규명하기 위해 성분 분석과 미세조직을 관찰하였다. 성분분석 결과, 몸체, 귀, 고리, 뚜껑, 꼭지부위는 주성분이 Cu-Sn-Pb인 3원계 청동합금으로 주조하였고, 몸체와 귀는 구리의 함량이 높은 구리못으로 고정하였음을 확인하였다. 미세조직은 α상이 대부분이며 Cu와 S이 주성분인 비금속개재물이 존재한다.