A Study on Synthesis of (Mo.W)$\textrm{Si}_2$ Composites

장대규,Jang, Dae-Gyu,Abbaschian, R. Materials Research Society of Korea 1999 한국재료학회지 Vol.9 No.1

(Mo.W)Si$_2$ composites were fabricated by vacuum hot-pressing elemental Mo, W and Si powders at various temperatures. Elemental Mo, W and Si powders were alloyed in the proper proportions to form solid solutions. The microstructure and properties of these materials was characterized by using x-ray diffraction, optical microscopy, energy dispersive x-ray spectroscopy and Vicker's technique. It was found that tungsten was mainly substituted for Mo atoms, and made a completed solid solution of (Mo.W)Si$_2$ over 1$600^{\circ}C$. The lattice parameters and Vickers hardness increased largely with increasing reaction temperature by the most soluble elements, due to the solid-solution hardening.

철기 II 시대 이스라엘 도시화와 종교 연구

장대규(Jang, Dae-Gyu) 한국중동학회 2009 韓國 中東 學會 論叢 Vol.30 No.1

The thesis of this study is that urban life exercised a significant and positive influence upon Israelite religion during the Iron Age II period, 10th-6th centuries BCE. This study has attempted to demonstrate that the city and its urban life had an impact on Yahweh religion that exhibited positive outcomes. Israel acquired more formal structures, full-time cultic personnel(priests), and greater centralization of Yahweh worship. Although Israel shared some of the religious beliefs and practices of its neighbors as a results of its adoption of parts of the Canaanite cultural heritage, Israel's unique religion is clearly evident in its understanding of God and its practices in cult, liturgy, and urban life. Archaeology has provided useful information about the physical aspects of the city and city structures in ancient Israel. The physical layout of the city, structures, and objects used in their daily life has interpreted as to understand religious characteristics of the Iron Age II(1000-586 BCE). The physical aspects of the city will enhance out understanding of the urban setting and its characteristics. The city was historically and theologically seen as a place of refuge, of justice, and of religious life. A description of the development of religion during the monarchy is found in Genesis 28 and 35 in the pre-monarchic period. As indicated in 1 Kings 12, the religious development occurred as Israelite religion entered the urban setting. The contributions of urban life to YHWH Religion are found in the role of professional cultic functionaries whose primary role was to maintain the traditions of the past, the rite of festivals that brought urban and rural dwellers together in the city and its gate complex and exposed them to urban religious life, and the institution of the city gate that brought diverse peoples, the written tradition that preserved the practices of tradition, and the system of court that became a motif and expression of YHWH's concern for justice in the city.

다양한 유기계 지지체와 광촉매 Nano-ZnO 복합체를 활용한1,1,2-trichloroethylene 제거 효율 평가

장대규(Dae Gyu Jang),안호상(Hosang Ahn),김정연(Jeong Yeon Kim),안창혁(Chang Hyuk Ahn),이새로미(Saeromi Lee),김종규(Jong Kyu Kim),주진철(Jin Chul Joo) 大韓環境工學會 2014 대한환경공학회지 Vol.36 No.11

본 연구에서는 광촉매 nano-ZnO 분말을 수질정화에 사용 후 회수 공정을 생략하기 위해 지지체에 고정화/안정화 시발생하는 효율 저하를 유기오염물의 수착(sorption)으로 극복하고 복합체로부터 nano-ZnO의 탈리(detachment) 현상을 방지 하고자 실리콘(silicone), ABS (acrylonitrile-butadiene-styrene), 에폭시(epoxy), 부타디엔 고무(butadiene rubber)를 선정하여 nano-ZnO/Organic composites (NZOCs)를 제조하였다. 또한, 개발된 다양한 NZOCs의 수중 안정성을 규명 하고, 지하수 내 대표적인 난분해성 유기오염물인 1,1,2-trichloroethylene (TCE)를 대상으로 액상에서 제거 실험을 통해 NZOCs의 활용 타당성을 검증하였다. 연구 결과, 내수성실험을 통해 개발된 NZOCs는 수질정화 용도로 장기간 사용이 타당함을 확인하였다. 또한, FESEM,EDX, imaging 분석을 통해 Nano-ZnO/Butadiene rubber Composite (NZBC)는 다양한 공극과 균열에 nano-ZnO 분말이비교적 균질하게 부착된 반면, Nano-ZnO/Silicone Composite (NZSC), Nano-ZnO/ABS Composite (NZAC), Nano-ZnO/EpoxyComposite (NZEC)는 표면에 공극과 균열이 발달되지 않아 불균질한 부착이 이뤄졌음을 확인할 수 있었다. 또한, NZBC는초기농도 대비 60%의 TCE 수착 능을 보였는데 이는 다른 유기계 지지체와 달리 비결정성 고분자이며, TCE 분자의 소수성분배가 활발히 발생하였기 때문으로 판단된다. 액상에서 TCE의 제거효율(수착+광분해)은 NZBC가 99% 제거 효율로 가장 우수했으며, 복합체 주입량이 증가할수록 TCE 제거효율이 크게 증가하였다. 이러한 결과는 butadiene rubber의 우수한 수착능과nano-ZnO의 광촉매 기작이 동시에 발생하였기 때문인 것으로 판단된다. 마지막으로 액상에서 TCE 제거는 선형모델을 활용해서 비교적 잘 모사할 수 있었으며(R2≥0.936), NZBC의 총 반응상수(Kapp)는 UV에 의한 TCE 분해상수(Kphotolysis) 대비 2.64~3.85배로 높은 값으로 확인되어 butadiene rubber가 TCE 수착 효율이 우수하며, 광분해 기작을 억제하지 않는 지지체로 활용가능한 것으로 판단하였다. In this study, the various organic supports (i.e., silicone, acrylonitrile- butadiene-styrene, epoxy, and, butadiene rubber)with great sorption capacity of organic contaminants were chosen to develop nano-ZnO/organic composites (NZOCs) and to preventthe detachment of nano-ZnO particles. The water resistance of the developed NZOCs were evaluated, and the feasibility of thedeveloped NZOCs were investigated by evaluating the removal efficiency of 1,1,2-trichloroethylene (TCE) in the aqueous phase. Based on the results from water-resistance experiments, long-term water treatment usage of all NZOCs was found to be feasible. According to the FE-SEM, EDX, and imaging analysis, nano-ZnO/butadiene rubber composite (NZBC) with various sizes and typesof porosity and crack was measured to be coated with relatively homogeneously-distributed nano-ZnO particles whereas nano-ZnO/silicone composite (NZSC), nano-ZnO/ABS composite (NZAC), and nano-ZnO/epoxy composite (NZEC) with poorly-developedporosity and crack were measured to be coated with relatively heterogeneously-distributed nano-ZnO particles. The sorption capacityof NZBC was close to 60% relative to the initial concentration, and this result was mainly attributed to the amorphous structure ofNZBC, hence the hydrophobic partitioning of TCE to the amorphous structure of NZBC intensively occurred. The removal efficiencyof TCE in aqueous phase using NZBC was close to 99% relative to the initial concentration, and the removal efficiency of TCE wasimproved as the amount of NZBC increased. These results stemmed from the synergistic mechanisms with great sorption capabilityof butadiene rubber and superior photocatalytic activities of nano-ZnO. Finally, the removal efficiency of TCE in aqueous phaseusing NZBC was well represented by linear model (R2≥0.936), and the Kapp values of NZBC were from 2.64 to 3.85 times greaterthan those of Kphotolysis, indicating that butadiene rubber was found to be the suitable organic supporting materials with enhancedsorption capacity and without inhibition of photocatalytic activities of nano-ZnO.

철기 Ⅱ 시대 트랜스요르단의 에돔종교 연구 - 문헌적/고고학적 증거를 중심으로

장대규(Jang Dae-Gyu) 한국중동학회 2008 韓國 中東 學會 論叢 Vol.28 No.2

  The purpose of this article is to make an integrative study of the Edomite religion of the Iron Age Ⅱ period with its biblical, extrabiblical, and archaeological evidence. Although there are articles focusing on the Edomite religion, there are not thorough integrated study. In fact, more and more recent archaeological finds relating to the state of Edom in Transjordan such as the discoveries of Edomite sanctuaries require update and extended study to reveal its religion.<BR>  This study will investigate the ANE textual and archaeological evidence, but since there are at least biblical, extrabiblical, and archaeological evidence relating to the Edomite religion issue, this research will start from the written evidence, both biblical and extrabiblical. In terms of extrabiblical evidence, the most significant sources requiring close investigation are inscriptions. In addition to the epigraphic evidence, the archaeological artifacts will include the objects of temples, sanctuaries, figurines, some cult objects together with their archaeological contexts. Thus, this article will try to recognize the objects of their worship and the practices of their religious rituals.<BR>  Regarding the Edomite religion, this article will investigate certain new evidence requiring update study, including the excavated Edomite sanctuaries Busayra, "En Haseva, Horvat Qitmit, and some recently unearthed cult objects. Thus, this study will identify the Edomite religion through written evidence and pay special attention to Qos, the Edomite national deity.<BR>  First of all, although the biblical and extrabiblical evidence does not say much about Edomite religion during the Iron Age Ⅱ period, it is certain that the Edomites practiced polytheism as early as the first half of the eighth century BCE.<BR>  Secondly, although the biblical evidence does not indicate which deity/deities the Edomites worshiped, it is evident that the cult of Qos, an Edomite deity, had existed at least from the eighth century BCE. The identity of Qos as a deity can be attested by the blessing formula mentioned by a letter discovered from Horvat ‘Uza.<BR>  Thirdly, the structure from Busayra suggests the possibility of the existence of a temple in the capital of Iron Age Ⅱ Edom. The temple consists of a “cella” (or “holy of holies”), a staircase to the cella, a purification room, and some small rooms around the courtyard, possibly storerooms.<BR>  Fourthly, the shrines at Horvat Qitmit and ‘En Haseva together with their cult objects reveal various kinds of Edomite religious customs, including making sacrifice, presenting offerings, having sacred meals, burning incense, prayer, and presenting votive offerings.<BR>  Finally, the discovery of several anthropomorphic and zoomorphic figurines from Busayra, Tawilan, and Horvat Qitmit indicate that a fertility cult was part of the Edomite popular religion.

F-E16 : Nano-ZnO/Laponite 복합체 볼의 건조방법 선정 및 메틸렌블루(Methylene blue) 실험을 통한 환원력 측정

장대규 ( Dae Gyu Jang ),안호상 ( Ho Sang Ahn ),윤영한 ( Young Han Yoon ),안창혁 ( Chang Hyuck Ahn ),이새로미 ( Sae Ro Mi Lee ),오주현 ( Ju Hyun Oh ),주진철 ( Jin Chul Joo ) 한국물환경학회(구 한국수질보전학회) 2013 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2013 No.-

기원전 8-7세기 신-앗시리아 문헌에 나타난 모압(Moab)의 사회-역사적 상황 연구

장대규 ( Dae Gyu Jang ) 한국서양고대역사문화학회 2009 서양고대사연구 Vol.24 No.-

철기 II 시대 트랜스요르단의 암몬 종교 연구

장대규(Jang, Dae-Gyu) 한국중동학회 2009 韓國 中東 學會 論叢 Vol.29 No.3

Regarding the Ammonite religion, Milkom was the national deity of Ammon in Transjordan, and he was also the king of the Ammonite pantheon. The stone sculptures of Milkom with the Egyptian ‘atef crown is very unique in both sides of the Jordan, through there were some Ba‘al and El figurines wearing the similar crown. The Amman Citadel Inscription also indicates that Milkom was closely linked to the Ammonite royal house. Although it was recently reported that there was an Ammonite temple in its state capital Rabbath-Ammon, further information is still required regarding this site. In addition to Milkom, many Ammonite personal names and the plaster text from Tall Dayr ‘Alla suggest that El was another deity whose cult seems popular among the Iron Age II Ammonites. Beyond El, Ammon presents the most foreign elements among the three Transjordanian states, especially from the divine elements in the personal names and the motifs from the seals, including deities from Egypt, Canaan, Syria, Assyria, and Phoenicia. The local shrines also demonstrate another aspect of the Ammonite religion: Only the courtyard shrine at Tall al-‘Umayri whose main functions seems to be presenting votives rather than making animal sacrifice belongs to the Iron Age II period; however, other Ammonite shrines and cultic installations from the Late Bronze Age to Iron Age I periods suggest that the religious activities in Ammon seem to be very similar to other two Transjordanian states. In addition to the cultic installations, the variety of the Ammonite statues and figurines display the development of the Ammonite local traditions and the finds of figurines from many dwellings also indicate the widespread practice of domestic cults in this state. In terms of the burial practices, the Ammonite presents a picture similar to contemporary Moab, despite the fact that the ceramic anthropoid coffins with many handles were peculiar to Ammon.

논문(論文) : 고대 이스라엘 진흙 여인상의 기능에 관한 연구. 구마적/ 주술적 기능을 중심으로

장대규 ( Dae Gyu Jang ) 한국서양고대역사문화학회 2008 서양고대사연구 Vol.22 No.-

자전고온합성법으로 제조한 이규화몰리브덴 발열체의 소결특성에 미치는 소결조건 및 첨가물의 영향

심건주,장대규,서창열,김운백,Sim, Geon-Ju,Jang, Dae-Gyu,Seo, Chang-Yeol,Kim, Un-Baek 한국재료학회 1995 한국재료학회지 Vol.5 No.8

MoSi$_2$heating elements were fabricated using MoSi$_2$, powder prepared by SHS. Their apparent density, electrical resistivity, bending strength and victors hardness were measured as a function of sintering temperature, time and the amount of ceramic additives. The additives were A1$_2$O$_3$, SiO$_2$and bentonite which were added as a plastisizer. The electrical resistivity of MoSi$_2$decreased with the increase in the apparent density as expected. It decreased when the additives were added and the increase was the largest for the case of SiO$_2$. The bending strength and hardness decreased when the grain size becomes larger which is opposite to the expectation from the Hall-Petch type relation. Instead, they showed inverse proportionality with the volume fraction of pores probably in an exponential manner. The strength and hardness also decreased with the additives.

이규화 몰리브덴-텅스텐의 자전 고온 합성 반응 모델링

연순화,장대규,이철경,Yeon, Sun-Hwa,Jang, Dae-Gyu,Lee, Cheol-Gyeong 한국재료학회 2001 한국재료학회지 Vol.11 No.3

The Self-propagating High-temperature Synthesis (SHS) for synthesizing ($Mo_{1-z}$ , $W_{z}$)$Si_2$was conducted experimentally with the mole fraction of Tungsten(W) from z=0.0 to z=0.5. The temperature profile was measured according to the reaction time through the thermocouple that was equipped into the center of these samples. When the reaction front is propagated around the thermocouple, the highest temperature appears and we regard this temperature as the adiabatic temperature. We found out by experimental results that the reaction velocity is in the range of 2.14~1.35mm/sec and the adiabatic temperature is in the range of 1883~1507K for the six samples. The reaction velocity and the adiabatic temperature were inclined to decrease with an increasing of the mole fraction of Tungsten (W). The SHS modeling is presented in order to predict the temperature profiles and these results are compared with the experimental results. It is predicted that in case of increasing the initial temperature of these six samples, the reaction temperature increased and that the sample of z=0.5 needs the preheating up to 800~900K in order to become reaction temperature 1900K. 자전고온합성반응법을 이용하여 이규화 몰리브덴-텅스텐($Mo_{1-z}$ , $W_{z}$)$Si_2$을 합성하였다. 조성 (z)을 변화시켜 성형한 원통형 시편에 합성반응 중 전달되는 온도변화를 예측하기 위하여 시편의 중앙에 열전대를 삽입하였다. 반응 선단면이 열전대를 통과할 때 가장 높은 반응온도를 보이고 이것을 단열반응 온도라 간주하였다. 따라서 본 연구에서는 이러한 온도변화를 예측하기 위하여 자전조온합성반응의 모델링을 계시하고자 하였으며, 실험을 통하여 측정한 반응온도 분포곡선의 거동을 비교하였다. 각각의 시료에 대한 실험결과 측정된 반응속도는 약 2.14~1.35mm/sec, 반응온도는 1883K~1507K의 간을 보였다. 두 항 모두 텅스텐의 함량이 증가함에 따라 감소하는 경향을 나타냈으며, 수치해석을 통하여 거의 유사한 반응온도를 얻었다. 시료의 초기온도를 증가시킬 경우 반응온도는 증가함이 예측되었고, z=0.5인 시료에 대하여 반응온도가 1900k 이상이 되기 위해서는 약 800K-900K의 예열이 필요하였다.