• Title/Summary/Keyword: rare metals

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Qualitative Analysis of Research Papers of KIGAM World Class Laboratories (WCL) Candidates (논문 질적평가를 통한 KIGAM 세계수준 후보연구실 기술수준 평가)

  • Ahn, Eun-Young
    • Economic and Environmental Geology
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    • v.47 no.3
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    • pp.227-235
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    • 2014
  • For technology level assessment of KIGAM World Class Laboratories (WCL) candidates, bibliometric and qualitative analysis was conducted on their research papers listed on the SCIE database during 2009-2012. For the six research areas of geoscience and mineral resources, a research excellence indicator was applied using a Modified Rank Normalized Impact Factor (mrnIF), which was introduced by Heo et al. (2008) and Cho (2013). The KIGAM research department in rare metals utilization had the highest score for Impact Factor (IF) per paper in 2012 but the groundwater department or the exploration geophysics department came first based on the position and the mrnIF. Applying the mrnIF, the KIGAM research department in groundwater achieved excellent results in 2009 and 2011 and the urban mine department or exploration geophysics department came first place in other years. In the groundwater area, the percentage of research papers over 80 or 90 mrnIF, using Cho (2013)'s research excellence index, was the highest in 2011. The Cho (2013)'s excellent research indicator, 20%, the ratio of over 90 mrnIF was matched in the urban mining area for the whole research period, 2009-2012, and in the groundwater area for several years except 2010. Qualitative analysis of research papers can show the technology level of research departments. KIGAM World Class Laboratories (WCL) candidates should focus on increasing the quality and the quantity of their research papers.

Geochemical Properties of Deep Sea Sediment in the Benthic Environmental Impact Experiment Site (BIS) of Korea (심해 저층환경충격 시험지역의 퇴적물 지화학적 특성)

  • Kong, Gee Soo;Hyeong, Kiseong;Choi, Hun-Soo;Chi, Sang-Bum
    • Ocean and Polar Research
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    • v.36 no.4
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    • pp.407-421
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    • 2014
  • The benthic environmental impact experiment addresses environmental impacts at a specific site related to deep-sea mineral resource development. We have acquired several tens of multi- or box core samples at 31 sites within the Benthic environmental Impact Site (BIS) since 2010, aiming to examine the basic properties of surficial deep-sea sediment as a potential source for deep-water plumes. In this study, we present the geochemical properties such as major elements, rare earth elements (REEs), and heavy metal contents at the BIS. Such proxies vary distinctly according to the Facies association. The lithology of all core sediments in the BIS corresponds to both Association Ib and Association IIIb. The vertical profiles of some major elements ($SiO_2$, $Fe_2O_3$, CaO, $P_2O_5$, MgO, MnO) show noticeable differences between Association Ib and IIIb, while others ($Al_2O_3$, $TiO_2$, $Na_2O$, and $K_2O$) do not vary between Association Ib and IIIb. REEs are also distinctly different for Associations Ib and IIIb; in Association Ib, REY and HREE/LREE are uniform through the sediment section, while they increase downward in Association IIIb like the major elements; below a depth of 8 cm, REY is over 500 ppm. The metal enrichment factor (EF) evaluates the anthropogenic influences of some metals (Cu, Ni, Pb, Zn, and Cd) in marine sediments. In both Associations, the EF for Cu is over 1.5, the EF for Ni and Pb ranges from 0.5 to 1.5, and the EF for Zn and Cd are less than 0.5, indicating Cu is enriched but Zn and Cd are relatively depleted in the BIS. The vertical variations of geochemical properties between Association Ib and IIIb are shown to be clearly different, which seems to be related to the global climate changes such as the shift of Intertropical convergence zone (ITCZ).

Estimation of Total Material Requirement in Expressway Construction using Material Flow Analysis which is based on the Life Cycle Assessment (LCA기반 물질흐름분석 기법을 이용한 고속도로 건설에서의 총 자원요구량 산정)

  • Kong, Chan-Hwi;Hwang, Yong-Woo;Moon, Jin-Young;Kwak, In-Ho
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.8
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    • pp.403-410
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    • 2016
  • During expressway construction it has been input a lot of material, but it does not manage to estimate quantitatively. In this study, the total material requirement for construction of expressway, which separated direct material requirement and indirect material requirement each section was quantified by combining life cycle assessment (LCA) and material flow analysis (MFA). In the direct material requirement, sand 2.27E + 04 ton/km, limestone 1.02E + 04 ton/km and gravel 4.47E + 03 ton/km were required, in the indirect material requirement, gravel 2.75E + 04 ton/km, iron 9.80E + 03 ton/km and coal 9.74E + 03 ton/km were required. Material such as sand, limestone which has high direct material requirement is require of excess input prevention from construction site, and material such as iron, rare metals(chrome, nickel) and coal which has high indirect material requirement is require additional studies of resource management.

Removal of Fe, Si from Silicon Carbide Sludge Generated in the Silicon Wafer Cutting Process (실리콘 웨이퍼 절단공정(切斷工程)에서 발생(發生)하는 실리콘 카바이드 슬러지로부터 철(鐵), 실리콘 제거(除去))

  • Park, Hoey Kyung;Go, Bong Hwan;Park, Kyun Young;Kang, Tae Won;Jang, Hee Dong
    • Resources Recycling
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    • v.22 no.2
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    • pp.22-28
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    • 2013
  • In the present study, the possibility of recovering and recycling the silicon carbide(SiC) from a silicon sludge by removing Fe and Si impurities was investigated. Si and SiC were separated from the silicon sludge using centrifugation. The separated SiC concentrate consisted of Fe, Si and SiC, in which Fe and Si were removed to recover the pure SiC. Leaching with acid/alkali solution was compared with the vapor-phase chlorination. The Fe concentration removed in the SiC was 49 ppm, and it was separated by leaching with 1 M HCl solution at $80^{\circ}C$ for 1 h. The Si concentration removed in the SiC was 860 ppm, and it was separated by leaching with 1M NaOH solution at $50^{\circ}C$ for 1 h. The SiC concentrate was chlorinated in a tubular reactor, 2.4 cm in diameter and 32 cm in length. The boat filled with SiC concentrate was located at the midpoint of the alumina tube, then, the chlorine and nitrogen gas mixture was introduced. The Fe and Si concentration removed in the SiC were 48 ppm and 405 ppm, respectively, at $500^{\circ}C$ reactor temperature, 4 h reaction time, 300 cc/min gas flow rate, and 10% $Cl_2$ gas mole fraction.

The Study on Investigation of Advantages and Disadvantages of Acupoint Sticking in Dog-Days and Side Effects of Acupoint Sticking in Dog-Days (삼복첩의 장단점에 대한 인식조사와 삼복첩 부작용에 대한 연구)

  • Kim, Hyung Joong;Lee, Eun Ju;Lee, Sun Haeng;Chang, Gyu Tae
    • The Journal of Pediatrics of Korean Medicine
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    • v.28 no.4
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    • pp.96-107
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    • 2014
  • Objectives The purpose of this study is to understand what caregivers think advantageous and disadvantageous regarding Acupoint sticking Dog-days. Also, to know whether Acupoint sticking in Dog-days affect vital signs, and to investigate if occurrence of side effects are related to application duration, sweat, or compliance to precautionary measures. Methods Survey has been handed out to parents of the children who took Acupoint sticking in Dog-days. 10 days after the first dose was administered, survey was performed to examine any side effect occurrences, characteristics of sweat, duration of application, parents' thought about this therapy. Also, vital signs were checked before the first dose, and 10 days after to see any differences in vital signs in regards to this therapy. Results Preferable opinions about Acupoint sticking in Dog-days are 'convenient than herbal medications' (76.5%), 'less reluctance of child' (47.1%), 'reasonable price' (20.6%), 'good effectiveness' (17.6%), 'less side effect' (14.7%), 'no worry about agrochemicals or heavy metals uptake' (11.8%). Downsides were 'difficult to admit to hospital right on the Dog-days' (73.5%), 'no conspicuous effectiveness' (11.8%), 'expensive' (5.9%), 'reluctance of child' (2.9%). Vital sign differences were minimal when examined before and after Acupoint sticking in Dog-days. Side effects occurred 5 times in 34 cases, and they were erythema, itchiness, and hot sensation. There were no scars or blisters reported. All 5 cases were resolved without any interventions within 3 days. Conclusions Acupoint sticking in Dog-days doesn't affect vital signs. Severe side effect is rare, reported side effects were relatively mild, suggesting that it may be safe and well-tolerated. 'Convenience' (76.5%) is biggest advantage of Acupoint sticking in Dog-days and 'less reluctance of child' is also big advantage of Acupoint sticking in Dog-days. 'Difficulty to admit to hospital right on the Dog-days' (73.5%) is biggest disadvantage of Acupoint sticking in Dog-days.

Introduction of Several Albitite-greisen Type Deposits of Korea (한국 알비타이트-그라이젠형 광상의 소개)

  • Yoo, Jang Han;Koh, Sang Mo;Moon, Dong Hyeok
    • Journal of the Mineralogical Society of Korea
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    • v.25 no.4
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    • pp.221-231
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    • 2012
  • Uljin cassiterite deposit had been known to be a pegmatitic origin derived from the Wangpiri (Buncheon) granitic gneiss of Precambrian period. Lithium ore also shows the same origin and its lithium bearing mineral was ascertained to be a taeniolite. But the presence of leucocratic granites which played the role of host rocks haven't been clearly designated yet in these provinces. Even though Bonghwa and Youngweol sericite deposits situated in the vicinities of Hambaeg syncline had been known to have their host rocks as Hongjesa Granites of Precambrian period and Pegmatitic migmatite of unknown age respectively. But younger leucocratic granites are characterized by more amounts of albite and sericite (muscovite-3T type) than those of the older granitic rocks which contain plenty of biotite and chlorites. Although the younger granites show rather higher contents of alkalies such as $Na_2O$ (0.13~8.03 wt%) and $K_2O$ (1.71~6.38 wt%), but CaO (0.05~1.21 wt%) is very deficient due to the albitization and greisenization. Manisan granite, which is assumed to be Daebo granite which intruded the Gyunggi Gneiss Complex was again intruded by leucocratic granite whose microclinized part changed into kaolins. Taebaegsan region shows a wide distribution of carbonate rocks which are especially favorable to the ore depositions. And the presence of alkali granites which formed in the later magmatic evolution are well known to be worthwhile to the prospections of various rare metals and REEs resources.

Sulfuric Acid Dissolution of Carriers for Recovering Platinum from the Spent Petroleum Catalysts (석유 폐촉매로부터 백금 회수를 위한 담체의 황산용해)

  • Lee Jae-chun;Jeong Jinki;Kim Byung-su;Kim Min Seuk;Cho Young Soo
    • Resources Recycling
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    • v.13 no.1
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    • pp.14-21
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    • 2004
  • Spent catalysts containing platinum were generated in petroleum refinery and other chemical industries. The reclamation of platinum metals from such wastes has long been attempted in view of their rare, expensive and indispensable nature. In this study, the recovery of platinum from petroleum catalysts was attempted by a method consisting mainly of dissolving alumina carrier with sulfuric acid thereby concentrating insoluble platinum. Also, platinum dissolved partially in sulfuric acid was recovered by a cementation method using aluminum metal as a reductive agent. The effect of temperature, time, concentration of sulfuric acid, and pulp density on the dissolution of carrier was investigated. When the carrier of platinum catalyst was $\Upsilon-Al_2$O$_3$ about 95% alumina was dissolved in 6.0 M sulfuric acid at $100^{\circ}C$ for 2 hours. When the carrier was the mixture of $\Upsilon-Al_2$$O_3$ and $\alpha$-$Al_2$$O_3$ about 92% was dissolved after 4 hours. As a result, more than 99% of platinum could be recovered by this method and aluminum sulfate was also obtained as byproduct.

Enhancement of Denitrification Capacity of Pseudomonas sp. KY1 through the Optimization of C/N ratio of Liquid Molasses and Nitrate (액상 당밀과 질산성 질소의 C/N 비율에 따른 Pseudomonas sp. KY1의 탈질 능력 및 그 최적비율에 관한 연구)

  • Lee, Kyuyeon;Lee, Byung Sun;Shin, Doyun;Choi, Yongju;Nam, Kyoungphile
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.9
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    • pp.654-659
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    • 2013
  • This study was conducted to identify an optimal ratio of carbon to nitrogen (C/N ratio) for denitrification of nitrate using molasses as an external carbon source. A series of batch and column tests was conducted using an indigenous bacterium Pseudomonas sp. KY1 isolated from a nitrate-contaminated soil. For the initial nitrate-nitrogen concentration of 100 mg-N/L, batch test results indicated that C/N ratio of 3/1 was the optimal ratio with a relatively high pseudo-first-order reaction constant of $0.0263hr^{-1}$. At C/N ratio of 3/1, more than 80% of nitrate-nitrogen concentration of 100 mg-N/L was removed in 100 hrs. Results of column tests with a flow velocity of 0.3 mL/min also indicated that the C/N ratio of 3/1 was optimal for denitrification with minimizing remaining molasses concentrations. After 172 hrs of column operation (35 pore volumes) with an influent nitrate-nitrogen concentration of 100 mg-N/L, the effluent met the drinking water standard (i.e., 10 mg $NO_3$-N/L).

Geophysical and Geological Exploration of Cobalt-rich Ferromanganese Crusts on a Seamount in the Western Pacific (서태평양 해저산 고코발트 망간각 자원평가를 위한 광역 탐사 방안)

  • Kim, Jonguk;Ko, Young-Tak;Hyeong, Kiseong;Moon, Jai-Woon
    • Economic and Environmental Geology
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    • v.46 no.6
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    • pp.569-580
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    • 2013
  • Co-rich ferromanganese crusts (Fe-Mn crusts) distributed on the seamounts in the western Pacific are potential economic resources for cobalt, nickel, platinum, and other rare metals in the future. Regulations for prospecting and exploration of Fe-Mn crusts in the Area, which enables the process to obtain an exclusive exploration right for blocks of the fixed size, were enacted recently by the International Seabed Authority, which led to public attention on its potential for commercial development. Evaluation and selection of a mining site can be established based on abundance and grade of Fe-Mn crusts in the site as well as topography that should be smooth enough for mining efficiency. Therefore, acquisition of shipboard echo-sounding and acoustic backscatter data are prerequisite to select potential mine sites in addition to visual and sampling operations. Acoustic backscatter data can be used to locate crust-covered areas in a regional scale with the understanding of acoustic properties of crust through its correlation with visual and sampling data. KIOST had collected the topographic and geologic data to assess the resources potential for Fe-Mn crusts in the west Pacific region from 1994 to 2001. However, they could not obtain acoustic backscatter data that is crucial for the selection of prospective mining sites. Therefore, additional exploration surveys are required to carry out side scan sonar mapping combined with seafloor observation and sampling to decide the blocks for application of an exclusive exploration right.

Development of Web-Based Platform System for Sharing Manufacturing Technologies on Housing Parts of Mobile Products (휴대폰 외장부품 제조기술 공유를 위한 웹기반 플랫폼 개발)

  • Jung, Tae Sung;Yoon, Gil Sang;Heo, Young Moo;Lee, Hyo Soo;Kang, Moon Jin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.1
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    • pp.113-119
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    • 2013
  • Despite rapid changes in the structure of industry, manufacturing remains a key industry for economic progress, promotion of trade, increased employment, and the creation of new industries. Production technologies are essential for strengthening the competitiveness of small- and medium-sized manufacturing industries. However, it is very difficult to standardize and systematically propagate production technology from an experienced worker to an inexperienced worker because these technologies are generally improved by the skilled people in a workshop. In this study, we introduce a Web-based platform system consisting of a knowledge authoring tool, technology database, semantic database, and Web portal service for sharing production technologies for the exterior housing parts of mobile products. By investigating various cellular phone designs, reference form factors for three types of mobile phone housings were designed based on the standard features. In addition, several manufacturing technologies and considerable information such as reference mold designs and molding conditions optimized using CAE and recent R&D outputs are stored in this system.