• Acta Via Serica
• /
• v.8 no.2
• /
• pp.95-124
• /
• 2023

Over the past 30 years, intense archaeological research has revealed a great increase in regional and transregional object mobility across the South China Sea during its Iron Age (500 BCE to 500 CE). Some objects had moved from a long distance: intaglios, seals, fine ceramic, glass containers, and gold coins of Mediterranean origin; and large bronzes, mirrors, and lacquerware connected to central East Asia. This evidence has given rise to larger-scale explanations, among which the most prominent has been the growth of (maritime) Silk Road trade. Scholars are divided as to whether the Silk Road is a suitable concept, with some emphasizing its orientalist overtones and colonial baggage and others finding it useful for the investigation of interregional networks trading in silk and other commodities. This paper explores how productive the Silk Road concept or metaphor really is for understanding transregional connectivity and social change in Iron Age Southeast Asia.

• Journal of Conservation Science
• /
• v.30 no.4
• /
• pp.345-351
• /
• 2014

Chemical and Pb isotope analysis were performed in order to determine the origin of bronze artefacts excavated from the Inyongsaji site in South Korea. The result of ICP-MS shows that they are tin bronzes in which lead was not intentionally added during production. Pb isotope data analyzed by TIMS are plotted in the southern region of Korea and China of the distribution map drawn by Mabuchi(1985). On the other hand, the identical isotope data are plotted in the Taebaek basin and the Olcheon metamorphic belt correspondent to zone2 and zone3 respectively. It is believed that the isotope data on the tin bronzes which have very low lead content can be used to trace the origin of copper ore rather than those of either lead or tin ore. Pb istope analysis allows diverse interpretation as it can be applied to any object containing trace amounts of lead. In addition, accumulation of isotope data as well as further studies will improve reliability of the provenance studies.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1998.06a
• /
• pp.395-398
• /
• 1998

Lithium insertion has been studied in a number of vanadium oxides with special regard to their application as the active materials in rechargeable lithium cells. Very high stoichiometric energy densities for lithium insertion are found for several of these materials. Some vanadium oxides, e.g. V$_2$ $O_{5}$ and V$_{6}$ $O_{13}$, are now being used in commercially developed rechargeable Li batteries. Another material which is receiving remarkable attention for this kind of cells is LiV$_3$ $O_{8}$. In variety of ternary lithium-vanadium oxides, the lithium content can be varied between certain limits without major changes in the vanadium oxygen lattice. In our worts, the oxides which do net form these thermodynamically stable bronzes can still accommodate large amounts of lithium at ambient temperature, forming kinetically stable insertion compounds. These compounds owe their existence to the whereas lithium is easily introduced into these open structures. The oxides investigated are rather poor electronic conductors; the conductivity decrease with increase in the lithium content. Improvements in the electrode fabrication technique are needed to alleviate this Problem.oblem.

• Korean Journal of Metals and Materials
• /
• v.46 no.1
• /
• pp.26-32
• /
• 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.

• Journal of Conservation Science
• /
• v.30 no.4
• /
• pp.417-425
• /
• 2014

Color characteristics of the Cu-Sn alloys (bronze) in as-cast conditions were determined by reference to the $L^*$, $a^*$, $b^*$ color space. Results show that the values of $a^*$ and $b^*$ decrease with the increase in Sn levels, indicating that the colors of bronze alloys are increasingly away from red and yellow with the increase in the fraction of the ${\delta}$ phase while the opposite is true with the ${\alpha}$ phase. It has also been found in similar experiments with the Cu-22% Sn alloys that heat treatments in varying conditions produce subtle differences in their color characteristics as observed in the $L^*$, $a^*$, $b^*$ color space, due likely to the formation of various phases in different fractions.

• 보존과학연구
• /
• s.21
• /
• pp.77-99
• /
• 2000

Tumuli located in Chodang-dong in Kangreung City are sitesexcavated by the Museum of Kangreung University in 1993.Ofthese sites, a gilt bronze crown and gilt bronze sword with ring pommel with a tri-leaf ornament were excavated from the B-16tumulus. Underneath the gilt bronze crown was the gilt bronzes word with ring pommel with tri-leaf ornament, and these artifacts were treated with Polyurethane foams on the spot followed by special measures for conservation. This manuscript describes measures for conservation andanalysis with regard to the gilt bronze crown, gilt bronze sword with ring pommel with tri-leaf ornament and gilt bronze beltornaments. Bronze on the gilt bronze crown was completely corroded, therefore it was consolidated together with soil in the back of the artifact with Paraloid B72 after cleaning. Polyurethanefoams bottom was finished by applying the mixture of Epoxy resinAW106 and HV935K with soil. On the sword with ring pommel, the wooden part of the hilt was coated with Paraloid B72 (in Xylene) and the blade was consolidated with Paraloid NAD-10 30% after desalting with Sodium sesquicarbonate method. The gilt bronzebelt ornaments were treated with 3% Benzotriazole, coated with Paraloid B72 and then joined by using Cyanlacrylate. Specimens for the gilt bronze crown and gilt bronze belt ornaments were produced and gilding layers were examined under a metallographic microscope. The gilt bronze crown and the gilt bronze belt ornament maintained relatively good gilding quality with uniform gilding layers. Analysis of wood for the sheath of the sword with ring pommel revealed it to be Juglans mandshurica. Further more, analysis of constituents for a blue colored grassbead from dissolution of Polyurethane foams found it to be from the $Na_2O$-CaO-$AI_2O_3$-$SiO_2$ family.

• Journal of the Mineralogical Society of Korea
• /
• v.27 no.4
• /
• pp.263-270
• /
• 2014

This paper was researched that provenance of the raw material for bronze relics excavated Cheonghaejin using the distribution of lead isotope ratio based on galena ores of South Korea. Also we want to make sure that the trace elements appearing as a by-product can be used as a secondary indicator for provenance research. In the case of the galena map of the East-North Asia (Mabuchi, 1985), data are plotted in China area. Therefore it is estimated that most bronzes were produced with lead ore from China. On the other hand, the same data are plotted in the Okcheon Metamorphic Belt and Yeongnam Massif of the galena map of South Korea (KOPLID, 2012). Also the contents of Ag and Sb are available as indicator due to separate ores from similar zone in lead isotope ratio.

• Journal of Advanced Navigation Technology
• /
• v.17 no.5
• /
• pp.524-544
• /
• 2013

In this paper, A tow system of miniature establishes each motor to individual 1C1M methods to control for a permanent magnet synchronous motors (PMSM) is constructed. You assume that is wiring having had the ability that can all absorb regenerative power which occurred when permanent magnet synchronous motors(PMSM) brake is all used to it, and to occur about agreement use scope expansion my electricity. To regenerative braking power securities of a PMSM and to stop of the bronzes my a control security, and that the electricity as you apply to vector control method and an speed sensor of controller to microprocessor, And you studied to speed, motor electricity energy control method to the algorithm and you brake a revival by regenerative braking power securities of a permanent magnet synchronous motors. It is proposed that motor control method to the algorithm you brake a revival by electricity braking power securities, you do to simulations regarding a momentum load and experiment.

• The Journal of the Petrological Society of Korea
• /
• v.10 no.3
• /
• pp.157-171
• /
• 2001

This study investigated the effects of Pb/Tl ratio, Pb concentration and concomitant matrix elements on the measurement of Pb isotope ratios using multi-collector ICP/MS (AXIOM MC model). Accuracy and reproducibility of Pb isotope ratios in NBS 981 solution were estimated for 42 data measured from March to August 2001. Pb isotopes measured in rocks, bronzes and sediments were compared to data measured by TIMS. Reproducibilities for $^{206}Pb/^{204}Pb,\; ^{207}Pb/^{204}Pb,\;and\;^{208}Pb/^{204}Pb$ ratio were about 500 ppm (2sd) and for $^{207}Pb/^{206}Pb$\;and\;^{208}Pb/^{206}Pb$ were 100~200 ppm for 200 ng of Pb in NBS 981 solution. The optimum conditions for the analysis of Pb isotope ratios with AXIOM MC for best accuracy and reproducibility were defined as follows; 1) Pb/Tl ratio is about 10 2) Pb concentration is about 100 ng/ml 3) correction for mass discrimination is performed by exponential law using 2.3887 of $^{205}Tl/^{203}Tl$ and Pb mass fractionation factor empirically obtained from $ln(^{208}Pb/^{206}Pb)-ln(^{205}Tl/^{203}Tl)$ relationship. The sample data measured with MC/ICP/MS for acid-digested and chemically separated rock samples, and acid-digested bronze samples and sediment samples coincide with those of TIMS within analytical errors. Therefore, MC/ICP/MS is a rapid analytical technique for Pb isotope ratios with the similar precision compared with TIMS.

• Journal of Conservation Science
• /
• v.27 no.4
• /
• pp.421-430
• /
• 2011

Thermal conditions in practice at the traditional bronze workshop of the Korean Folk Village in Yongin were examined along with the microstructures of some high tin bronze objects made there. Laboratory experiments approximating the conditions of the workshop were also carried out and the results were compared. The operating temperature of the workshop furnace was measured to range from $750^{\circ}C$ to $850^{\circ}C$ while the surface temperature of an object, upon its removal from the furnace for additional thermo-mechanical treatments, was generally in the range of $600^{\circ}C$ to $685^{\circ}C$. This variation in working temperatures was reflected in varying microstructures developed upon quenching. The products of the Folk Village were found to consist of microstructures where the ${\alpha}$ grains of the Cu-Sn system were distributed in the background of different phases including the ${\beta}$-martensite phase, retained ${\gamma}$ phase, ${\alpha}+{\delta}$ eutectoid or their mixtures. This variability, which is also identified in objects made in ancient times as well as in our laboratory experiments, suggests that the actual thermal conditions given during the quenching treatments are much more complicated than is inferred from the temperature measurements. This paper will present detailed accounts of the thermo-mechanical treatments as observed in the high tin bronze workshop of the Korean Folk Village and discuss the evolution of varying microstructures in terms of the substantial variability involved in the implementation of the traditional forged high tin bronze technology of Korea.