• Title/Summary/Keyword: Natural minerals

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A Study on Corrosion Resistance of Reinforced Concrete Structures using Natural Inorganic Minerals (천연 무기 광물계 혼화재료를 혼입한 철근콘크리트 구조물의 부식저항성에 관한 연구)

  • Tae, Sung Ho;Park, Jae Young;Kim, Jae Young;Park, Jae Seung;Kyung, Je Woon;Nam, Ho Yoon
    • KIEAE Journal
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    • v.7 no.4
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    • pp.127-133
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    • 2007
  • As a fundamental study on the corrosion resistance of reinforced concrete structures using Natural Inorganic Minerals exposed to carbonation environment, The test specimens were concrete(W/C=60%) with Natural Inorganic Minerals content of 0%, 10%. Accelerated carbonation and autoclave corrosion accelerated curing were then conducted with them. The corrosion resistance of steel in concrete with Natural Inorganic Minerals content of 0%, 10% was examined by corrosion form, half-cell potential, polarization resistance, corrosion area and weight loss after 24 hours of autoclave corrosion accelerated curing.The results of the study showed that as for steel in concrete with Natural Inorganic Minerals content of 10%, the corrosion resistance was more excellent than steel in concrete with Natural Inorganic Minerals content of 0%.

Removal of Arsenic(V) from Aqueous Solutions by Using Natural Minerals

  • Mohapatra Debasish;Mishra Debaraj;Chaudhury G. Roy;Das R.P.;Park, Kyung-Ho
    • Resources Recycling
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    • v.15 no.5 s.73
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    • pp.38-46
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    • 2006
  • The removal of arsenic(V) using four different natural minerals were evaluated. Parameters like contact time, pH, adsorbent dosages, and As(V) concentration were optimized. The kinetics of adsorption was observed to be fast and reached equilibrium within 2h. As(V) adsorption on studied minerals was dependent on pH and followed a pseudo-second-order reaction model. For kaolin, maximum adsorption was found at pH 5.0. Whereas, in case of other three minerals, a pH range of 6.0-7.0 was found to be the best for As(V) adsorption. The maximum adsorption capacity (Q) was calculated by fitting Langmuir equation to the adsorption isotherms obtained under a specified condition. From the slope of best fit, the Q values were calculated to be 2.07, 2.15, 1.95 and 0.86 mg As(V)/g of bauxite, wad, iron ore and kaolin, respectively. Desorption of As(V) from loaded materials was dependent on the type of leaching reagents used. Based on the results, it was found that among the studied natural minerals, wad was the best As(V) adsorbent.

Permeability Coefficient Properties of Mortar using Natural Inorganic Minerals (무기계 천연광물을 사용한 모르타르의 특수계수 특성)

  • Kim Sung-Bae;Park Sun-Gyu;Song Ha-Won;Byun Keun-Joo;Kim Jae-Young
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05b
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    • pp.445-448
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    • 2005
  • In this paper, waterproofing improvement of cement mortar is researched by comparing cement mixed with natural inorganic minerals with OPC under the same condition. The result shows that cement mixed with natural inorganic minerals has less permeability and absorption compared to OPC, which can be used as important data for improvements of durability and waterproofing of concrete structures.

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자연환경 변화와 광물의 역할

  • 김수진
    • Proceedings of the Petrological Society of Korea Conference
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    • 2000.05a
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    • pp.3-11
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    • 2000
  • The earth environment consists of four spheres : geosphere, hydrosphere, atmosphere and biosphere. The geosphere consists mostly of minerals. It, however, contains some water and air in its shallow depth. Although hydrosphere and atmosphere consist predominantly of water and air, respectively, both contain some minerals. The biosphere consisting of various organisms is present in the interfaces of geosphere, hydrosphere and atmosphere. The natural environment of the earth is continuously changing by the interaction of four spheres. It suggests that out relevant environmental problems can not be revolved without understanding the natural relationship of these four spheres. Minerals in our environment are very important because they are the main constituent materials of the earth and they control our environment. The roles of minerals in our environment have not been understood even in the scientific society. Thus their roles have been neglected. Review of studies on the environmental mineralogy so far made at our laboratory and others show that minerals control the environment in various ways. Minerals neutralize the acid water as well as acid rain. Minerals in soils and rocks are major neutralizer of the acid rain. Salinization of sea water is attributed to the ionic substitution between minerals and sea water. Some minerals control the humidity of the air. Corals, the products of biomineralization, are the main carbon controller of the air. Minerals also adsorb heavy metals, organic pollutants and radioactive nuclides. Such remarkable functions for controlling the environment come from the mineral-water reaction and biomineralization. All these phenomena are subjects of the environmental mineralogy, a new field of earth science.

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Serum Levels of Minerals, Ceruloplasmin, and Ferroxidase Activity in Female Adolescent Smokers

  • Kim, Jung-Hee;Moon, Jeong-Suk;Kim, Ju-Young
    • Journal of Community Nutrition
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    • v.1 no.2
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    • pp.88-97
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    • 1999
  • The purpose of this study was to investigate the nutritional status of serum minerals, ceruloplasmin, and ferroxidase activity in female adolescent students according to their smoking status. The subjects were 87 non-smokers and 88 smokers, who were female high school students. The smokers were divided into tow groups by smoking status, 35 light smokers(pack-year<1) and 53 smokers(pack-year$\geq$1). The serum concentrations of 6 minerals were determined by ICP emission spectroanalyzer. The serum concentration of ceruloplasmin and ceruloplasmin ferroxidase activity were determined. All data were statistically analyzed by SAS PC package program. The serum minerals concentrations of all subjects were in a normal range. There were significantly differences in the concentrations of serum copper, zinc, magnesium, and phosphorus by smoking status while there were no significant differences in the concentrations of serum iron and manganese by smoking status. Furthermore there were no significant differences in the ceruloplasmin concentration and ferroxidase activity by smoking status. In conclusion, smoking status altered the serum levels of some minerals in healthy young women. The minerals levels in light smokers with relatively short pack-year(pack-year<1) were altered compared to those in non-smokers or smokers. This finding seemed to be consistent with the results of previously published data related to antioxidant vitamin and lipid peroxide levels. However further research is needed to clarify these findings in female adolescent smokers.

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Durability performance of concrete containing Saudi natural pozzolans as supplementary cementitious material

  • Al-Amoudi, Omar S. Baghabra;Ahmad, Shamsad;Khan, Saad M.S.;Maslehuddin, Mohammed
    • Advances in concrete construction
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    • v.8 no.2
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    • pp.119-126
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    • 2019
  • This paper reports an experimental investigation conducted to evaluate the durability performance of concrete mixtures prepared utilizing blends of Type I Portland cement (OPC) and natural pozzolans (NPs) obtained from three different sources in Saudi Arabia. The control concrete mixture containing OPC alone as the binder and three concrete mixtures incorporating NPs were prepared keeping water/binder ratio of 0.4 (by weight), binder content of $370kg/m^3$, and fine/total aggregate ratio of 0.38 (by weight) invariant. The compressive strength and durability properties that included depth of water penetration, depth of carbonation, chloride diffusion coefficient, and resistance to reinforcement corrosion and sulfate attack were determined. Results of this study indicate that at all ages, the compressive strength of NP-admixed concrete mixtures was slightly less than that of the concrete containing OPC alone. However, the concrete mixtures containing NP exhibited lower depth of water penetration and chloride diffusion coefficient and more resistance to reinforcement corrosion and sulfate attack as compared to OPC. NP-admixed concrete showed relatively more depth of carbonation than OPC when subjected to accelerated carbonation. The results of this investigation indicates the viability of utilizing of Saudi natural pozzolans for improving the durability characteristics of concrete subjected to chloride and sulfate exposures.

Analysis of Minerals in the Hair of Mental Retardation

  • Lee, Ju-Young;Choi, Won-Chul
    • Journal of Environmental Health Sciences
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    • v.31 no.3
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    • pp.187-191
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    • 2005
  • Several heavy metals are known to give some kinds of mental retardation although abnormal X-chromosome is closely connected with genetic disease such as mental retardation. This study dealt with the influence of minerals in the hair of mental retardation people. Minerals were analyzed by Inductively Coupled Plasma Mass Spectrometer (Sciex Elan 6100, Perkin-Elmer corporation, Foster, CA, USA). The nutritional elements such as Ca, Na, K were higher level (p<0.01) in normal group than in the mental retardation group. The toxic elements such as Cd (p<0.01) and As were higher level in the mental retardation group than in normal group. But Pb is not significant difference among the all groups including normal group.

A Study on Properties Engineering of Concrete Using Natural Inorganic Minerals (무기계 천연광물을 혼입한 콘크리트의 공학적 특성에 관한 연구)

  • Kim Sung-Bae;Song Ha-Won;Park Sun-Gyu;Park La-Hyuk
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2005.05a
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    • pp.81-84
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    • 2005
  • Due to increased demands for durable and high-performance concrete structures, the use of admixtures has become essential. In this paper, material properties, and durability of concrete mixed with natural inorganic minerals(R-1) are obtained from test results. Through the comparisons with OPC(Ordinary Portland Cement) concrete, the R-1 concrete shows improved compressive strength and durability.

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Mineral Contents in Bottled Natural Water and Estimation of Their Intake by Korean Adults (일부 무기질의 생수 중 함량 분석과 생수를 통한 섭취량 평가)

  • Kim, Moo-Kyung;Sim, Jin-Ah;Eom, Hee-Jung;Kim, Myung-Hee;Choi, Mi-Kyeong
    • Journal of the Korean Dietetic Association
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    • v.16 no.2
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    • pp.116-121
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    • 2010
  • Minerals play an important role in the body as essential nutrients. However, it is not easy to meet DRIs because food sources of minerals are limited. Recently, consumption of bottled natural water has been increasing in Korea due to water pollution and distrust of tap water. The present study was conducted to investigate mineral contents in bottled natural water and their intakes among Korean adults. We analyzed eight minerals in seven kinds of bottled natural water by ICP-spectrometry and conducted a survey on the intake status of water and bottled natural water with 400 Korean young adults. The mean contents of Ca, Mg, Fe, Zn, Cu, Mn, Se, and Mo in bottled natural water were 22.45${\pm}$22.48 mg/L, 10.59${\pm}$9.97 mg/L, 0.27${\pm}$0.18 ${\mu}g/L$, 2.06${\pm}$1.48 ${\mu}g/L$, 5.47${\pm}$0.70 ${\mu}g/L$, 1.43${\pm}$0.37 ${\mu}g/L$, 1.90${\pm}$0.96 ${\mu}g/L$, and 3.34${\pm}$0.79 ${\mu}g/L$, respectively. The mean age, height, weight, and BMI were 22.76 years, 174.94 cm, 68.64 kg, and 22.41 $kg/m^2$ for males (n=150) and 21.25 years, 162.04 cm, 51.05 kg, and 19.46 $kg/m^2$ for females (n=250), respectively. The respective daily intakes of total water and bottled natural water as water itself were 670.30 ml and 212.20 ml for males and 488.04 ml and 132.72 ml for females. The daily intakes of Ca, Mg, Fe, Zn, Cu, Mn, Se, and Mo from bottled natural water were 4.76 mg, 2.25 mg, 0.06 ${\mu}g$, 0.44 ${\mu}g$, 1.16 ${\mu}g$, 0.30 ${\mu}g$, 0.40 ${\mu}g$, and 0.71 ${\mu}g$ for males and 2.98 ${\mu}g$, 1.41 mg, 0.04 ${\mu}g$, 0.27 ${\mu}g$,0.73 ${\mu}g$, 0.19 ${\mu}g$,0.25 ${\mu}g$, and 0.44 ${\mu}g$ for females, respectively. Overall, the contents of Ca, Mg, and Se in bottled natural water were relatively high and the daily intakes of these minerals were 0.4~1.0% of the DRIs.

Au-Ag Minerals and Geneses of Weolyu Gold-Silver Deposits, Chungcheongbukdo, Republic of Korea (월유광산산(月留鑛山産) 금(金)-은(銀)광물(鑛物)과 광상(鑛床)의 생성환경(生成環境))

  • Lee, Hyun Koo;Yoo, Bong-Cheal;Jeong, Kwang Young;Kim, Kee Hyun
    • Economic and Environmental Geology
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    • v.27 no.6
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    • pp.537-548
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    • 1994
  • The Weolyu gold-silver deposits at Hwanggan, Chungcheongbukdo, is of a late Cretaceous $(74.24{\pm}1.63Ma)$ epithermal vein-type, and is hosted in the quartz porphyry of late Cretaceous age. Based on mineral paragenetic sequence interpreted from vein structure and mineral assemblages, three stages mineralization were distinguished. A variety of ore minerals occurs including pyrite, sphalerite, chalcopyrite, galena with small amount of electrum, native silver, argentite, pearceite, sb-pearceite, argyrotite. The gangue minerals are quartz, rutile, calcite, apatite, fluorite and rhodochrocite. Wall-rock alteration such as pyritization, chloritization, sericitization, silicification is observed near the quartz veins. Au-Ag minerals were crystallized at middle and late stage of the two mineralization sequences. Results from the analysis of fluid inclusion and thermodynamic calculation indicate that Au-Ag mineral deposits were formed primarily by cooling and dilution of hydrothermal fluids($165{\sim}313^{\circ}C$, 0.4~2.4wt.% equivalent NaCl) with some degree mixing of meteoric water.

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