• Economic and Environmental Geology
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• v.18 no.2
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• pp.139-150
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• 1985

Skarn at the Dielette formed largely in calc-silicate hornfels at the contact with the Flamanville granite. The skarn consists mainly of garnet and pyroxene, and less frequently vesuvianite. Traversing toward calc-silicate hornfels wall rock from a central zone of the skarn, the general sequence of formation of mineral assemblages is: (1) dark brown garnet (2) pale brown garnet-vesuvianite-pyroxene, and (3) pyroxene-prehnite-scapolite-wollastonite envelopes (designated as transition zone) developed between skarn and calc-silicate hornfels. The central zone of the skarn consists mainly of dark brown garnets (garnet I) that contain little or no pyroxene. The pale brown garnet (garnet II) is associated with pyroxene and vesuvianite. The sequence of these garnets results from the zonal growth outward. There is an abrupt discontinuity in composition between garnet I formed in early stage and garnet II in late stage, while each garnet shows relatively uniform composition. At the zone in contact with the granite, the iron contents of garnets decrease toward the marginal zone of the skarn, from an average value of 36 mole % andradite in garnet I to 18 mole % andradite in garnet II. At the zone distant from the granite, the andradite component decreases from 28 mole % in garnet 1 to 19 mole % in garnet II. The variation of the iron contents of pyroxenes is also similar to that of garnets. The sharp discontinuity in composition of garnets and pyroxenes suggests that the skarn of study area was formed by infiltration metasomatic process. The results of the analyses of mineral assemblages of the transition zone by chemical potential diagrams suggest that the transition zone was made by the diffusion of the elements Ca, K and Fe from the skarn to the calc-silicate hornfels contact zone. The estimated temperatures and $Xco_2$ for the formation of the transition zone show $300^{\circ}C$$440^{\circ}C$ and $0.07{\pm}0.05<Xco_2<0.02{\pm}0.01$ at 1 Kb respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.1
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• pp.36-43
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• 2016

The aim of this study was to evaluate the effect of blood contamination on the push-out bond strength and surface morphology of tricalcium silicate materials; Biodentine$^{(R)}$, Theracal$^{(R)}$ and mineral trioxide aggregate. The standardized lumens of root slices prepared from extracted single-root human teeth were filled with Biodentine$^{(R)}$, Theracal$^{(R)}$ and mineral trioxide aggregate by manufacturer's instruction. The specimens were randomly divided into 2 groups (n = 20) for each material and then incubated for 4 days at $37^{\circ}C$; control group (phosphate buffered saline solution) and experimental group (fetal bovine serum). The push-out bond strengths were then measured by a universal testing machine and the surface morphology of each experimental group was analyzed by scanning electron microscope. Biodentine$^{(R)}$ and Theracal$^{(R)}$ showed higher push-out bond strength compared with mineral trioxide aggregate after exposure to fetal bovine serum. A substantial change in the surface morphology of each material was observed after exposure to fetal bovine serum. In conclusion, the push-out bond strengths of Biodentine$^{(R)}$ and Theracal$^{(R)}$ were higher than mineral trioxide aggregate when exposed to blood contamination. Therefore, it is supposed that the use of Biodentine$^{(R)}$ and Theracal$^{(R)}$ is appropriate in the presence of blood.

• Journal of the Korean Ceramic Society
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• v.32 no.2
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• pp.171-182
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• 1995

Five eucryptite and ten spodumene compositional powders were syntehsized from three sillimanite group, two kaolin group, and five pyrophyllite group silicate minerals. Those powders were isotatically pressed and fired at 1200~135$0^{\circ}C$ for 2 hrs, and then the sintered bodies were characterized. Silicate minerals with molar ratio of Al2O3 to SiO2 correspond to those of eucryptite and spodumene are kaolin and pyrophyllite group silicate minerals, respectively. Sintering characteristics of eucryptite from kaolin group and spodumene from pyrophyllite group mineral were superior to those from other silicate minerals. Eucryptite sintered bodies with 95~97% relative densities and densified microstructures can be obtained using Hadong pink kaolin as starting materials by sintering over broad temperature zone(1250~135$0^{\circ}C$). The eucryptite sintered bodies which were fired at 130$0^{\circ}C$ for 2hrs, from Hadong pink kaolin had within 3.0wt% microstructural compositional variations compaired with stoichiometric compound, and had good negative thermal expansiion property with -3.55$\times$10-6/$^{\circ}C$ thermal expansion coefficient. Spodumene sintered bodies which were prepared from pyrophyllite group silicate minerals, had dense microstructures and high densities by densification through liquid phase sintering with enlarged temperature range. The specimens which were fired at 130$0^{\circ}C$ for 2 hrs from Gusipyrophillite, had dense microstructure with crystallines mainly, and low thermal expansion property with 0.62$\times$10-6/$^{\circ}C$ thermal expansion coefficient. The porous texture and residual glass phase in LAS system ceramics which were prepared from silicate minerals, tend to increase the thermal expansion properties of sintered bodies to positive direction.

• Journal of Pharmaceutical Investigation
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• v.14 no.4
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• pp.170-177
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• 1984

For the purpose of improving the fluidity of enteric-coated powders, various mineral silicates were added during spray drying process. Aqueous slurries of cimetidine, mineral silicates containing CMEC (carboxy methyl ethyl cellulose) were spray dried using a centrifugal wheel atomizer. The finely agglomerated powders obtained by this process were flowing as opposed to the original powders. The effect of four mineral silicates (colloidal silica, talc, bentonite, and kaolin) on the micromeritic properties and dissolution profiles of spray dried agglomerates were examined.

• The Journal of the Petrological Society of Korea
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• v.5 no.1
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• pp.21-34
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• 1996

Contact-metamorphosed calc-silicate hornfels of the Hwanggangni formation adjacent to Daeyasan granite in Goesan are characterized by the mineral assemblages. tremolite-clinozoisite-alkali feldspar-calcite, diopside-grossular-vesuvianite, and wollastonite-diopside-phlogopite-grossular-vesuvianite, indicating low $X_{CO_2}$ condition during contact metamorphism. Two trends of fluid-rock interactions are recognized; combination of infiltration and buffering in the outer portion of the aureole and fluid-dominated behavior in the most part of the aureole. Modal abundance of diopside produced during metamorphism was measured in order to estimate fluid/rock ratios and permeabilities with the assumption that equivalent volume of fluids estimated from the fluid/rock ratios flow through the rock body. The calculated fluid/rock rations and permeabilities range from 0.6 to 9 and $10^{-19}$ to $10^{-17}$ meabilities in the calc-silicate hosted contact aureoles and expected values during progressive metamorphism by theories.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.259-262
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• 2012

Recently, as the national policy of green growth is promoted, construction field also makes an effort to reduce CO₂ gas released when producing cement continuously. In other words, as the method solving environmental pollution and resources exhaustion, lots of mineral material compounds such as blast furnace slag powder which is industrial by-product, fly ash, red mud, etc. are examined to bo used as the substitute good of cement Therefore this study is to investigate the hardening characteristics of alumino-silicate inorganic binder using red-mud used as a accelerator of industrial by-product such as fly ash and blast furnace slag powder according to curing temperature. As a result, it is effective to use red-mud as the accelerator of inorganic binder with other additory accelerators.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.521-526
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• 2002

In this paper, we described about the characteristic evaluation of environment-friendly ceramic paint with calcium-silicate mineral as a main binder. Particularly, we performed discharge of the environmental poisoning materials(e.g. VOCs, heavy metal, etc.), and properties of paint slurry and coating film of the ceramic paint. In the comparison of the ceramic paint with natural paint and mineral paint which were known as our environment-friendly paints, ceramic paint had good characteristics in the environmental safety and properies of wet slurry and dried coating film.

• Journal of the Mineralogical Society of Korea
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• v.12 no.2
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• pp.77-90
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• 1999

Characteristics and variations of chemical compositions in Co-rich crusts occurred in the EEZ of the Republic of Marshall Islands were reviewed. Correlation coefficient analysis, hierarchical cluster analysis, and Q-mode factor analysis for 62 samples were done in this study. All data were selected and gathered from the open file report of the cooperative cruise done by United States Geological Survey with Scripps Institute of Oceanography, University of Hawaii or Korea Ocean Research Development Institute. The average of crust thickness. Co content, and Ni content of 62 samples from the 21 seamounts were 30mm, 0.58 wt% and 0.40%, respectively. The mineral phases and associated elements assigned by correlation coefficients, cluster analysis and Q-mode factor analysis are following four. 1) CFA: P, Ca, CO2, Y, Sr: 2) Mn-oxide mineral: As, Mn, Co, Na: 3) Al-silicate mineral: Pd,Si, Al, Cu, Fe: 4) PGE-bearing mineral: Rh, Pt, Ir.

• Journal of Environmental Health Sciences
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• v.23 no.3
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• pp.56-65
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• 1997

Chemical analysis, statistical analysis and geochemical study were carried out to investigate the influence of the geology on the chemical characferistics of the mineral water in Taegu area. A simple comparision between the chemical components of the mineral water and their bedrocks indicates that the bedrock types in the catchmerit area control the chemical characteristics of the surface water. However more objective evidences for the mineral water-bedrock relationship come from the statistical analyses(cluster analysis and factor analysis). The results of the statistical analyses suggest that the bedrock type factor explains the data variation seven times as much as pollution does, which evidently indicates that the bedrock in the study area mainly control the mineral water chemistries. The results of comparision of the statistical analyses results with the mineral weathering reactions and mineral stability diagrams can be summarized as follows: 1. Plagioclase weathering to kaolinite provides SiO$_2$ , Ca$^{2+}$ and Na$^+$, and muscovite weathering to kaolinite provides K$^+$, and amphibole and mica minerals weathering to kaolinite provides F to the mineral water. Most of Ca$^{2+}$ and Mg$^{2+}$ in the mineral water are the products of carbonate mineral dissolution. SO$_4^{2-}$ may be the byproduct of sulfide oxidation. 2. The weatering of silicate mineral produces Ca-rich smectite and kaolinite, but Ca-rich smectite is unstable and will be transformed to more stable kaolinite because of the continuous dilution of the mineral water by precipitation. By Hashimoto's Mineral Balance Index, S-10 and S-12 mineral spring water were evaluated tasty and healthy water, S-9 and S-11 mineral spring water were evaluated tasty water and S-7, S-8 and S-13 mineral spring water were evaluated healthy water.

• Computers and Concrete
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• v.20 no.6
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• pp.705-710
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• 2017

The effectiveness of mineral additives in suppressing alkali-silica reactivity has been studied in this work. Experimentation has been performed in accordance with the procedures prescribed in ASTM C 1567. In the scope of the investigation, a quarry aggregate which was reactive according to ASTM C 1260 was tested. In the experimental program, prismatic mortar specimens measuring $25{\times}25{\times}285mm$ were produced. Ten sets of production, three specimens for each set, were made. Length changes were measured at the end of 3, 7, 14 and 28 days and then expansions in percentage have been calculated. Fly ash, silica fume, and metakaolin have been used as cement replacement in different ratios for the testing of the alkali-silicate reactivity of the aggregate. In the mixes performed, the replacement ratios were 20%, 40%, and 60% for the fly ash, and 5%, 10%, and 15% for the silica fume, and 5%, 10%, and 15% for the metakaolin. Mixes without mineral additives were also produced for comparison. The beneficial effect in suppressing alkali-silica reactivity is highly noticeable as the replacement ratios of the mineral additives increase regardless of the type of the mineral additive used. Being more concise, the optimum concentrations of using silica fume and metakaolin in mortar in suppressing ASR is 10%, respectively, while it is 20% for fly ash.