• 암석학회지
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• 제15권2호
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• pp.81-89
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• 2006

전라북도 지방에 분포하는 번암, 동진, 적상 및 북창 광산에서 채취한 납광석광물에 대한 납 동위원소 분석을 실시하였다. 그 결과 광상별로 상당히 다른 납 동위원소 조성을 가짐을 확인하였다. 번암광산, 북창광산 및 동진광산의 납 동위원소값이 형성하는 선형변화는 그 기울기가 매우 급하기 때문에 연대로 해석하기는 곤란하며 이 광상들의 납은 주로 선캠브리아 기저지각과 중생대 화강암질암의 두 종류 단성분들로부터 유래하였을 가능성을 제기하였다. 광상의 형성시 이러한 근원물질들로부터 유래한 납의 혼합비율은 광상마다 상당히 다른 것으로 추정된다. 이는 광화작용시 존재했던 유체의 순환이 매우 국지적인 범위에서 제한적으로 이루어졌기 때문인 것으로 판단된다 동진 광상의 경우는 광상에 배태된 납의 근원이 상당부분 기저지각에서 용출된 것임을 시사하며, 광화작용시 화성암은 운광암으로서보다는 유체의 순환을 야기한 열원으로서 중요한 역할을 담당한 것으로 판단된다.

• 한국재료학회지
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• 제20권10호
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• pp.524-534
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• 2010

Glass was fabricated using refused coal ore obtained from the Dogye coal mine in Samcheok. We additionally used soda ash and calcium carbonate to make a glass with the chemical composition of soda-lime glass, and we also used white, brown, and green glass cullet to make various kinds of colored glass. Transparent glass was fabricated by melting batch materials including refused coal ore at $1550^{\circ}C$ for 1 hr in an electrical furnace. The light transmittance and color chromaticity were measured by a UV/VIS/NIR spectrometer. Transparent glass with a light transmittance of over 80% was fabricated using normal refused coal ore and white glass cullet. Various kinds of colored glass with a light transmittance of 30-80% were fabricated using refused coal ore and brown or green glass cullet. The light transmittance of the mixed color glass samples, fabricated using normal refused coal ore and brown glass cullet and green glass cullet, indicated 30-47%, a relatively low value, in the condition of a cullet ratio of 20-50%. The characteristics of the color chromaticity of the glass samples were indicated in a chromaticity diagram by x-coordinates, y-coordinates, Y (lightness). The values of x-coordinates and y-coordinates were moved with a regular directional property according to the kind and amount of glass cullet. Therefore, we concluded that refused coal ore can be used for raw materials of color glass products like art glass and glass tile.

• 한국광물학회지
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• 제11권2호
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• pp.85-96
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• 1998

The sericite ore is formed by the hydrothermal alteration of rhyodacitic welded tuff. The alteration zone of the host rock can be classified into four types based on the mineral assemblages ; sericite, quartz-sericite, silicified and propylite zone. The sericite ore mainly occurs as vein types and fault clay along the fault plane in the quartz-sericite zone. Mineral components of the sericite ore are mainly sericite with minor diaspore, corundum and pyrite. The sericitic porcelaineous ore is mainly composed of quartz and sericite. Accessory minerals are muscovite, diaspore, sphene, corundum, pyrite, iron-oxides and etc. The chemical compositions of K2O, Al2O3, and ignition loss in the sericite ore increase largely than that of the host rock, while the compositions of SiO2, Na2O and Fe2O3 decrease. XRD patterns of the heat-treated sericite ores show the formation of mullite at $1,200^{\circ}C$. and the diaspore-bearing sericite ore forms mullite and corundum at $1,200^{\circ}C$. The differential thermal analysis of the sericite ores show small endothermic peak at 645~668$^{\circ}C$. and the diaspore-bearing sericite ore shows a strong endothermic peak at $517^{\circ}C$. It indicates that the decomposition of diaspore appear at lower temperature than that of sericite. The thermal expansivity of the sericite ores show the similar pattern. The sericite ores show the thermal expansivity of 3.3~4.7% at 900$^{\circ}C$ and 0.39~0.75% at 1,20$0^{\circ}C$, respectively. DTA-TG curves of the sericite ores show closely relations with the thermal expansivity.

• Nuclear Engineering and Technology
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• 제56권5호
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• pp.1880-1886
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• 2024

To elucidate the mechanism of damage caused by hyphae and organic acids produced by Aspergillus Niger on the surface and internal structure of uranium ore, direct uranium leaching, indirect uranium leaching and semidirect uranium leaching were conducted, and the surface morphology, strength, mineral crystallinity, porosity, and permeability of the ore were analyzed. The results demonstrated that the combination of biomechanical forces exerted by hyphae and the complexation effects of organic acids led to the dissolution of SiO₂ and other substances on the surface of ore, resulting in exfoliation from the exterior to the interior, thereby promoting uranium recovery. Furthermore, the proton exchange involving H⁺ and the complexation of organic acids resulted in the dissolution of cations within the ore, causing destruction to the crystal lattice structure of minerals and increasing the porosity and permeability inside the ore. The dominant factor contributing to ore damage during recovery was organic acids.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2004년도 제28회 KOSCO SYMPOSIUM 논문집
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• pp.141-148
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• 2004

Coal combustion in an iron ore sintering bed is a key parameter that determines quality of the sintered ores and productivity of the process. In this study, effects of the different types of coal coke and anthracite - on the combustion in the iron ore sintering bed are investigated by modeling and experiment. Fuel characteristics of coke and anthracite are observed through a few basic analysis and thermo-gravimetric analysis. It was found that coke has a higher reactivity than anthracite due to the difference of surface area and density. Those characteristics are reflected to the 1-D unsteady simulation of the iron ore sintering bed. Calculation results show that different reactivity of the fuel can affect the bed combustion, which implies the further investigation should be performed for obtaining optimal combustion conditions in the sintering bed.

• Nuclear Engineering and Technology
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• 제30권4호
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• pp.308-317
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• 1998

Ensuring occupational radiation exposure(ORE) as low as is reasonably achievable(ALARA) has been one of very important requirements in a nuclear power plant. It is well known that about 70 percent of occupational dose has incurred from maintenance jobs in the outage period. To reduce occupational dose effectively, the high-dose jobs in the outage period should be identified with their dose reduction potentials and methods. In this study, a PC-based ORE database program, INSTORE, is developed to evaluate ORE doses in individual jobs, and the ORE data of Kori Units 3 and 4 are assembled to the database. Based on customary job classification, radiation work is classified into 26 main jobs which comprise 61 detailed jobs, and occupational doses are assessed according to each detailed job. As a result, high-dose jobs are identified with dose reduction priority in terms of collective ORE dose. It is recommended that adeqaute dose reduction methods for these jobs should be prepared to improve their working conditions and procedures.

• 한국연소학회지
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• 제9권2호
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• pp.30-37
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• 2004

Coal combustion in an iron ore sintering bed is a key parameter that determines quality of the sintered ores and productivity of the process. In this study, effects of the different types of coal - coke and anthracite - on the combustion in the iron ore sintering bed are investigated by modeling and experiment. Fuel characteristics of coke and anthracite are observed through a set of basic analysis and thermo-gravimetric analysis. Coke has a higher reactivity than anthracite due to the difference of surface area and density, and these characteristics are reflected in the 1-D unsteady simulation of the iron ore sintering bed. Calculation results show that different reactivity of the fuel can affect the bed combustion.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.857-862
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• 2002

철도차량의 주행장치는 비틀림 선로를 주행할 경우 윤중감소가 발생하게 되며 이 값은 모든 하중 조건 및 공기스프링의 충기/배기 상태에서 UIC/ORE 보고서에서 규정한 기준치 60% 이내를 준수하여야만 한다. 이 논문은 인도 DMRC 전동차를 대상으로 시험을 실시하여 DMRC 선로 중 최악의 조건에서 UIC / ORE 에서 규정하고 있는 차량의 윤중감소율( Wheel Off-loading)의 기준을 만족하는 지에 대한 평가한 것을 기술하였다.

• 자원환경지질
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• 제1권1호
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• pp.9-34
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• 1968

Manganese ore deposits of the Samhan Changgun Properties are located at the valley of west-lope-side of Changgun-bong (1132m) occupied over the Myon border between Sochon-myon and Jaesan-myon Pongwha-gun, Kyongsang-Pukdo. Geology of the more property and it's vicinity consists of Wonnan formation and Yulri formation of pre-Cambrain and Changgun limestone formation, Mica-schist formation, quartizite formation and Jaesan formation (containing coal bearing zone the unknown age. And granites and dykes were intruded into the above formation later. 1. Management deposits is embedded the formation of Janggun limestone especially Contact zone in the contact zone to of Chunyang Granite limestone enclosed by Granite, and Maginal zone of fault line in the limestone. Therefore, Chunyang Granite is Closely related to ore deposit. Pegmatite which is near by ore deposit was intruded before mineralization and it seems to be a channelway of ore solution. The most important ore deposits of property grouped into south deposit, east deposit, east-Gachon deposit, South-Gachon deposit, Durimgok deposit and West deposit, out-crops at several place. Besides these deposits there also are several prospects on outcrop scathered. Hydrothermal alteration take place strongly in the well rock and it's sequence are Characterized as following; 1) Dolomitization 2) Carbonization 3) Mamgamotozation 4) Pyritization 5) Silicification 6) Oxidation 2. The grade of manganese dioxide is up to Mn 45% in Maximum, but generally, averaging Mn 30~35% of high grade ore and averaging Mn 30~32% of manganese carbonates are mined in his property.

• 자원환경지질
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• 제11권4호
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• pp.143-167
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• 1978

The Sangdong tungsten (mostly scheelite) mine is located on the southern limb of a major syncline, the Hambaeg syncline, in a thick sequence of lower Paleozoic sedimentary rocks in the mideastern part of south Korea. Productive scheelite mineralization in Sangdong area is confined to one single formation, the Myobong Slate. Four major ore beds, which have an lateral extension over than 1 km and were not heavily subjected to spatial disturbance, are developed in the Myobong Formation. The original materials of the ore-comprising horizones were probably of either calcareous or silceous sediments. The four ore beds, especially in the case of Main ore bed, display both lateral and vertical zoning. Association quartz-mica-scheelite is predominant in the central, while association hornblende-quartz-diopside-scheelite, diopside-garnet and wollastonite-garnet are developed in this order towards the periphery of the ore beds. Petrologically, two phases of thermometamorphism are recognized. The first phase is represented by the association wollastonite-garnet and diopside-garnet, while the second phase by the association hornblende-quartz-diopside-scheelite and quartz-mica-scheelite. The associations of the second phase do constitute prodctive ore. The high background value of tungsten in the area surrounding the Sangdong mine reveals that the area can be considered a geochemical zone enriched in tungsten. Studies on the trace element patterns were carried out to draw useful criteria for the purpose of future geochemical exploration in the area. The increasing trend of the ratio Rb $({\times}1000)/K_2O$ of the Myobong Slate towards the known mineralization area proved to be indicative for the presence of tungsten mineralization.