충남 연기군 동면 합강리 유적 출토 직물류 및 목제 빗의 과학적 분석

조남철,김우현,김수철,Cho, Namchul,Kim, Woohyun,Kim, Soochul 한국문화재보존과학회 2014 보존과학회지 Vol.30 No.4

A scientific analysis of ancient textiles provides significant data to understand weaving techniques and culture of textiles in each region and charateristics of materials used at that time. In addition, species identification of waterlogged wooden objects is a scientific analysis method that allow us to verify information of relation of foreign species trade and exchange, of preferable species through kinds of wooden products, and of forest environment as well as method setting of conservation. As a result of a species analysis about historical textiles and a wooden comb in a bronze bowl that were excavated from Hapgang-ri, Dong-Myun, Yungi-gun, Chungcheongnam-do, Textile1 and Textile3 are identified as Urticacese Boehmeri nivea ; ramie, Textie2 is identified as Malvaceae Gossypium herbaceum, and a wooden comb is identified as Betulaceae Betula spp. It is expected that this result will help to make further comparative studies, identifying species of textiles and trees of ancient times.

Reduced Recombination Losses with Enhanced Dielectric Permittivity of Donor Polymers in Polymer Solar Cells

Namchul Cho(조남철),Tae-Dong Kim(김태동),Alex K.-Y. Jen(알렉스 젠) 한국고분자학회 2018 폴리머 Vol.42 No.4

In this work, we have demonstrated that the electric field assisted poling of the donor polymer possessing conformationally labile nitrile groups increases dipolar polarization and dielectric permittivity. We find that the enhanced dielectric permittivity of the donor polymer reduces non-geminate recombination losses in bulk-heterojunction (BHJ) solar cells (SCs), resulting in increased open circuit voltage (V<SUB>OC</SUB>) compared with unpoled devices. This result reveals the importance of dielectric permittivity of polymers and also signifies the promising applicability of electric field assisted poling for high dielectric polymers in BHJ SCs.

포항 오어사 동종(보물1280호)의 성분조성과 납동위원소비 분석

조남철(Cho, NamChul),강형태(Kang, HyungTae) 한국상고사학회 2008 한국상고사학보 Vol.61 No.-

Chemical composition, microstructure and lead isotope ratio of Oeosa(temple) bronze bell (found in Hangsari, Ocheon-town, Nam-gu, Pohang-city, Gyeongbuk) have been analyzed by ICP-AES(Inductively Coupled Plasma-Atomic Emission spectrometry), Metallurgical Microscope and TIMS(Thermal ionization mass spectrometer), respectively. Major chemical composition of bronze bell consisted of copper (Cu), tin (Sn) and lead (Pb) and the ratio was about 74.1 : 10.5 : 13.1. Especially, Pb content was much richer than bronze bells before Goryeo period. It suggested that the lead was intentionally added to improve the casting and save the contents of copper and tin since Goryeo period. Microstructure of bronze bell was mainly made up α-phase and α+δ eutectoid phase instead of dendrite structure as the bell was cooled slowly after casting. The result of provenance study using lead isotope analysis have shown that the galena of bell was originated from the China South. The results of these scientific analysis of bronze bell can be used as basic data in comparison researches on manufacturing technology, source of raw materials of bronze bells to be found in the future. 경북 포항시 남구 오천읍 항사리에서 발견된 오어사 동종(1216년, 보물1280호)에 대하여 성분분석 및 금속조직 관찰을 통하여 동종의 제작기법을 그리고 납동위원소비를 분석하여 동종에 쓰인 납이 어느 지역의 방연석과 상관관계가 깊은지를 알아보았다. 동종의 성분을 분석한 결과, Cu 74.1%, Sn 10.5%, Pb 13.1%로 분석되었다. 특히 본 동종은 고려시대 이전 동종들에 비하여 납의 함량이 많은 것이 특징이다. 고대 동종의 경우 다량의 납함량은 주조성은 좋아지나, 종의 강도를 떨어뜨리고, 문양을 좋게 하지만 합금에서 편석되기 쉬우며 소리를 둔화시키는 작용을 하므로 억제하는 것이 일반적이다. 동종의 미세조직은 주조 후 서냉함으로 인해 수지상 조직이 아닌 α상과 α상 주위로 (α+δ) 공석상으로 이루어져 있으며 주조공정 이외에 특별한 열처리 흔적은 관찰되지 않는다. 마지막으로 납동위원소비를 통한 산지 분석결과, 동종의 주조시 사용된 납의 출처는 중국 남부지역의 방연석과 깊은 상관관계가 있음을 알 수 있었다. 오어사 동종은 지금까지 많은 발표가 이루어지지 못한 고려 동종의 성분조성 및 제작기법, 산지 연구에 관한 내용으로서 각 시대별 종의 조성별 또는 제작방법의 차이점 등을 연구하는데 중요한 자료가 될 것으로 본다.

Doctor Blade-Coated Polymer Solar Cells

Namchul Cho(조남철),Jong H. Kim(김종현) 한국고분자학회 2016 폴리머 Vol.40 No.5

In this work, we report polymer solar cells based on blade-coated P3HT:PC<SUB>71</SUB>BM and PBDTTT-EFT:PC<SUB>71</SUB>BM bulk heterojunction photoactive layers. Enhanced power conversion efficiency of 2.75 (conventional structure) and 3.03%(inverted structure) with improved reproducibility was obtained from blade-coated P3HT:PC<SUB>71</SUB>BM solar cells, compared to spin-coated ones. Furthermore, by demonstrating 3.10% efficiency flexible solar cells using blade-coated PBDTTT-EFT:PC<SUB>71</SUB>BM films on the plastic substrates, we suggest the potential applicability of blade coating technique to the high-throughput roll-to-roll fabrication systems.

중국 조선족 문학 연구: 조선족 작가 림원춘(林元春)을 중심으로

조남철 ( Cho Namchul ) 한국방송통신대학교 통합인문학연구소 2018 통합인문학연구 Vol.10 No.1

A study on the concept of “Korean Chinese Literature” and its meaning as Korean national literature is based on the literary works of Lim Won-ch’un. Due to the close relationship between Korea and China, “Korean Chinese” has become an important factor to understand the current Korean society, but as we can see in the dispute over the works of Yun Dong-Ju, whether they are Korean Chinese literature or Diaspora literature of overseas Korean, establishing proper relationship between Korean Chinese literature and Korean literature has been controversial. But from an academic perspective, Korean Chinese literature, especially overseas Korean literature in China until the independence of Korea, should be considered as a part of Korean literary tradition. Overseas Korean literature before 1945 is different from Korean Chinese literature after the foundation of the People's Republic of China, since Korean Chinese lived as Chinese nationalities so the territorial principle can be applied. It is also noticeable that Yun Dong-Ju considered China as ‘a foreign land.’ Thus, boundaries of Overseas Korean literature and Korean Chinese Literature needs to be clarified. But Koean Chinese Literature is still a valuable part of the Korean literary tradition. As < Mongdangchima > in which Lim Won-ch’un describes the traditions and ethnical characteristics of Korean Chinese society vividly using native Korean words shows, Korean Chinese Literature should be recognized as valuable assets of the Korean literary tradition after the unification of two Koreas. Thus, Korean Chinese Literature requires more scholarly attention.

오송 제2생명과학단지 2지점 1호 석실분 출토 금제장식의 과학적 분석

조현경 ( Hyunkyung Cho ),조남철 ( Namchul Cho ) 공주대학교 문화재보존과학연구소 2023 문화재과학기술 Vol.18 No.1

The gold plating (gilding) technique, a part of metalworking, involves applying a layer of gold onto the surface of other materials and has been known as an ancient technology. Although ancient gilding methods evolved differently depending on the region, the most representative techniques involved the use of foil gilding, gold leaf, and mercury. This study analyzes five gold ornaments excavated during the archaeological investigation at Tomb 1 in Section 2 of the Osong 2nd Life Science Complex. The findings reveal that button-shaped gold decorations made of iron were gilded using the leaf gilding method. XRF analysis indicates similar elemental compositions in all five ornaments, with gold ranging from 66.07 to 71.57% and silver from 16.77 to 18.34%. Copper, iron, aluminum, silicon, and phosphorus were also detected. Notably, the similar composition ratios of gold leaf suggest that the five analyzed items were made from the same material, indicating the use of gold that inherently contains silver, rather than an intentional alloying of gold and silver. Additionally, some gold ornaments were found attached to iron decorations, considered as separate artifacts from the iron decorations.

공주 안영리유적 출토 철부(鐵斧)의 보존처리 및 부식화합물 분석

전상희 ( Sanghee Jeon ),조남철 ( Namchul Cho ) 공주대학교 문화재보존과학연구소 2021 문화재과학기술 Vol.16 No.1

Gongju Anyeong-ri is one of the earliest prehistoric sites, and in this study, scientific analysis and conservation treatment were carried out on the two iron parts excavated from this site. For scientific analysis, the microstructure was observed using a metallographic microscope and SEM-EDS to identify the manufacturing techniques and characteristics of corrosion products. In addition, various types of rust, cracks, and foreign substances such as soil are thickly covered on the surface of the iron part, so scientific preservation treatment is required. The corrosion factor of the artifact was blocked and the original shape was restored. As a result of scientific analysis through microstructure, the material was confirmed to be white cast iron tissue. As it was buried for a long time, it could be confirmed that various iron oxides were layered, and some salts were concentrated. For scientific conservation treatment, X-ray imaging was performed to understand the internal state of the artifact. After removing foreign substances such as soil on the surface using the visual observation and X-ray imaging results, dehydration using alcohol to remove moisture from the iron part treatment was carried out. After that, it was preserved from further corrosion factors by drying, strengthening treatment using Paraloide B-72, bonding and restoration, and color matching. And it was finished by preserving it according to the original shape.

평택 칠원동 유적 출토 금속유물 및 슬래그의 과학적 분석

정다연 ( Dayeon Jung ),조남철 ( Namchul Cho ) 공주대학교 문화재보존과학연구소 2024 문화재과학기술 Vol.19 No.1

A scientific analysis using metallographic microscopy and SEM-EDS was conducted on the bronze spoon, slag, iron sickle, and iron plate excavated from the Chilwon-dong site in Pyeongtaek to study the manufacturing characteristics of the artifacts. The bronze spoon exhibited needle-shaped martensite, twinning, and strain lines within the α-phase, confirming that it is a hammered bronze spoon produced through high-temperature forging and quenching after casting. In the case of slag, fayalite, wüstite, and reduced Fe particles were identified in the microstructure, indicating that it is a byproduct of the iron smelting process. The iron sickle and iron plate were found to be hypoeutectoid steel materials with a microstructure of ferrite and pearlite coexisting. Notably, the iron sickle displayed elongated non-metallic inclusions, suggesting that it was manufactured through repeated forge welding and forging processes. Furthermore, wüstite with a high FeO content was observed within the non-metallic inclusions of the iron artifacts, demonstrating that wrought iron produced by the direct reduction method was utilized.

천안 가산리 유적 출토 철제초두(鐵製鐎斗)의 보존처리 및 부식 특성

신지수 ( Jisu Shin ),조남철 ( Namchul Cho ) 공주대학교 문화재보존과학연구소 2022 문화재과학기술 Vol.17 No.1

The tripod Iron Cauldron excavated from the remains of Gasan-ri in Cheonan was analyzed scientifically and conservation treatmented based on the results, and restored to its original shape. As scientific analysis, X-ray diffraction analysis, metallurgical microscope observation, SEM-EDS analysis, and Raman micro-spectroscopy analysis were performed. As a result of the analysis, a gray cast iron structure, which is rarely found in cast artifacts, was observed, and graphite corrosion, in which iron corroded first and only carbon remained, was confirmed. The main corrosion compounds were identified as Goethite and Magnetite by cross-verification of X-ray diffraction analysis and Raman micro-spectroscopy analysis. In order to understand the internal condition of the artifact, X-ray was taken, and a relic record card was created based on the visual observation. Based on the investigation before treatment, the treatment was performed in the order of removing foreign substances, first bonding, dehydration and drying, reinforcement and drying, second bonding and restoration, and color matching. Through scientific analysis, the manufacturing techniques and corrosion characteristics of iron artifacts were found, and based on the analysis results, appropriate conservation treatment was carried out to find the original form of the artifact. The overall shape is spherical, and the legs are confirmed as a ‘ㄱ’ shape, which is very rare in Tripod Iron Cauldron, and it is observed that the lip of Tripod Iron Cauldron part is connected from the upper body of Jeon(顎) to the lim of Tripod Iron Cauldron end and finished in a round shape. It seems to be of great value because it has a very unique form among Tripod Iron Cauldrons, and through this study, it is expected to be used as a basic data for iron candle conservation by accumulating data from conservation treatment and scientific analysis.

보령 웅천 구룡리 유적 출토 이식(耳飾)의 성분 조성과 제작기법

정다연 ( Dayeon Jung ),조현경 ( Hyunkyung Cho ),박수경 ( Sukyoung Park ),배채린 ( Chaerin Bae ),조남철 ( Namchul Cho ) 공주대학교 문화재보존과학연구소 2020 문화재과학기술 Vol.15 No.1

The scientific analysis of the six Earrings from Ungcheon Guryong-ri site in Boryeong, was conducted to find out the production techniques and components, and to compare and study the Earrings and material characteristics of Baekje excavated from other regions. Detailed images were observed through the actual microscopy to find out the manufacturing technique of Earrings, and the component analysis was made using a Portable X-ray Fluorescence Sesquential Spectrometer, a non-destructive component analyzer. As a results, All earrings excavated from Ungcheon Guryong-ri site in Boryeong, seem to have first made of copper-based core material, then wrapped the gold plate, heated and p r essed, and then applied the same process of forming a r ound shape. It is estimated that only copper remains due to the removal of the gold sheet from the burial condition of the 4 points of the Golden earrings excavated from Ungcheon Guryong-ri site in Boryeong. The remaining two points are 75-85% gold, 15-25% silver, and less than 10% copper. In addition to Ungcheon Guryong-ri site in Boryeong, Habjung-ri site in Buyeo and Bujang-ri site in Seosan showed that they were made with the same technique. It can be seen that the purity of gold used for earrings is generally less than 70% of gold for Bujang-ri site in Seosan excavated in the 4th and 5th centuries (Group III). For earrings excavated from Ungcheon Guryong-ri site in Boryeong and Habjung-ri site in Buyeo, more than 70% of gold can be confirmed (Group IV). Although the technique of making earrings does not change much, the purity of gold is higher in the 6th and 7th centuries than in the 4th and 5th centuries. Whether the result is a characteristic of social status, technological advancement, or the difference in the purity of smelted gold by region, it seems that there is still insufficient data on earrings by period. Further research is expected to be needed in the future.