• Economic and Environmental Geology
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• v.27 no.3
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• pp.231-236
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• 1994

Fluid inclusions have been studied in phenocryst quartz from the Cretaceous porphyritic granite. Three main types of fluid inclusion were found: liquid-rich inclusion (I type), gas-rich inclusion (II type) and solid-bearing inclusions (III-A, III-B). The solid-bearing inclusions (III-A, B) represent the earliest trapped fluids. They have salinities between 63 and 67.5 wt.% equivalent NaCl. These are high saline inclusions containing NaCl and KCl daughter crystals. Homogenization temperature inferred from the fluid inclusion study ranges from 620 to $700^{\circ}C$. Type I and II inclusions were observed within the same fracture. This cause for these differences in degree of filling is evidence of boiling. Salinities of type I and II inclusions range from 10.24 wt.% to 13.44 wt.%, from 8.4 wt.% to 11.48 wt.% NaCl equivalent, respectively.

• Economic and Environmental Geology
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• v.28 no.5
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• pp.445-454
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• 1995

The petrochemical data of the porphyritic granites of Cretaceous age in the Yonghwa-Seolcheon area show the trend of subalkaline magma, calc-alkaline magma, I-type granitoid and magnetite series. This granite is the relevant igneous rock of gold-silver mineralization in this mining district Fluid inclusions have been studied in phenocryst quartz from the Cretaceous porphyritic granite. Three main types of fluid inclusion were found : liquid-rich inclusion(I type), gas-rich inclusion(II type) and solid-bearing inclusions(III-A, III-B). The solid-bearing inclusions(III-A,B) represent the earliest trapped fluids. They have salinities between 41.0 and 67.5 wt% equivalent to NaCl. These are high saline inclusions containing NaCl and KCl daughter crystals. Homogenization temperature inferred from the fluid inclusion study ranges from 650 to $75^{\circ}C$ Type I and II inclusions were observed within the same fracture. This cause for these differences in degree of filling is evidence of boiling. Salinities of type I and II inclusions range from 9.87 wt% to 15.29 wt%, from 8.40 wt% to 14.64 wt% NaCl equivalent, respectively.

• Economic and Environmental Geology
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• v.30 no.6
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• pp.519-529
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• 1997

Volcanic rocks including rhyolitic tuff, rhyolite and welded tuff in the Bupyeong silver mine area form a topographic circular structure which is interpreted as a resurgent caldera. Granitic rocks are emplaced inside and outside area of the circular structure. Pervasive silver mineralization took place in the rhyolitic rock of the southwestern margin of the caldera. Gas and fluid incluson studies were carried out to investigate the petrogenetic evolution and post-magmatic alteration for the rhyolitic and granitic rocks. Gas compositions are characterized by a low $CH_4/CO_2$ ratio (0.004-0.005) for rhyolitic and inside granitic rocks and a high $CH_4/CO_2$ ratio (0.01~0.29) for outside granitic rocks such as the Kimpo and Incheon granites. Homogenization temperature of solid daughter mineral bearing fluid inclusion (III and IV types) and two phase fluid inclusion (I and II types) for quartz in the Bupyeong granites range from 400 to $500^{\circ}C$ and 121 to $514^{\circ}C$, respectively. Salinties vary from 20 to 30 wt% NaCl for type III and IV inclusions and less than 20 wt % NaCl for type I and II inclusions. The fluid inclusion data shows a considerable influx of the meteoric water toward post magmatic alteration stage.

• Economic and Environmental Geology
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• v.25 no.3
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• pp.283-296
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• 1992

The Keumryeong deposits is a low grade copper deposits in which copper minerals form disseminated grains and thin veinlets in felsic volcanics seem to be dacite. Alteration of the volcanics consists mainly pervasive propylitization and silicification. Potassic alteration characterized by biotite developed locally adjacent to southwestern contact of granodiorite body. Principal sulfide minerals in altered zone are mainly pyrite and lesser chalcopyrite. Chalcopyrite content in potassic zone is relatively higher than that of surrounding propylitized zone. Pyrite and chalcopyrite accompanies magnetite, molybdenite, sphalerite, pyrrhotite, arsenopyrite, pentlandite, marcasite, hematite, ilmenite, rutile, bismuthinite and native Bi as disseminations, veinlets and knots. Granodiorite body is propylitized and contains veinlets of pyrite, chalcopyrite and molybdenite. Fluid inclusions in sulfide-bearing quartz veinlets and quartz grains of felsic volcanics and granodiorite in altered zone consist of liquid-rich, vapor-rich, $CO_2-bearing$ and halite-bearing inclusions. These four types of inclusion intimately associated on a microscopic scale and indicate condensing or boiling of ore fluid during mineralization. Homogenization temperature of coexisting fluid inclusions are mostly in the range of 350 to $450^{\circ}C$. High salinity fluid contains 28.6 to 48.4 weight percent NaCI equivalent and moderate salinity fluid cotains 0.5 to 12.5 weight percent NaCl equivalent. Pressure estimated from $CO_2$ mole fraction of $CO_2-bearing$ inclusion range 160 to 375 bars. The Kigu copper deposits is a fissure filling copper vein developed 500 m south from the Keumryong deposits. Mineralogy and fluid inclusion data of the Kigu deposits are similar to that of the Keumryeong deposits. Homogenization temperature of fluid inclusions from the Kigu deposits are reasonable agreement with temperature estimated from sulfidation curve of cubanite-chalcopyrite-pyrite-pyrrhotite and pyrite-pyrrhotite mineral assemblages. Not only mineral occurrence and wall rock alteration in the Keumryeong deposits but also fluid inclusion data such as temperature, salinity, pressure and boiling evidences are similar to those of porphyry copper deposits.

• The Journal of the Petrological Society of Korea
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• v.8 no.1
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• pp.46-55
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• 1999

Fluid inclusions in granite and hydrothermal quartz indicate that three fluids have affected the Sannae granite. The earliest fluid is represented by three-phase aqueous fluid inclusions with high salinity (38 to 46 wt.% NaCl equiv.). It was exsolves from a crystallizing melt and trapped at a relatively high-pressure condition. The secong fluid is represented by two-phase aqueous fluid inclusion with low entectic temperatures (< $-40^{\circ}C$). low- to moderate salinity (3 to 24.0 wt.% NaCl equiv.) and high homogenization temperatures$ ($309^{\circ}C$$473^{\circ}C$)($. This fluid was trapped at higher pressures than 300-500 bars and precipitated molybdenite and wolframite in quartz veins. It was probably generted by fluid-host rock interactions since they show a wide range of salinity within a narrow range of homogenization temperatures. The final fluid is represented by an aquenous fluid boiling that separated into high-salinity (34-38 wt.% NaCl equiv.) and low-salinity fluid (0 to 8.7 wt.%) at $303-376^{\circ}C$ and 50-150 bars. These boiling fluids precipitated euhedral quartz in miarolitic cavities. The compositions of the final fluid was rather complex in the $H_2$O-NaCl-KCI-$FeCl_2$ system. The Sannae granite was a locus for repeated fluid events including magmatic fluids during the final stage of crystallization, the convection of hydrothermal fluids causing a fluid ascending, fluid boiling, and the local W-Mo mineralization and formation of miarolitic cavities due to thermal, tectonic and compositional properties of the felsic granite.

• Archives of Pharmacal Research
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• v.18 no.1
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• pp.22-26
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• 1995

The solubility and dissolution rate of naproxen (NPX) complexed with 2-hydroxypropyl-.betha.-cyc-lodextrin (2-HP.betha.CD) using coprecipitation, evaporation, freeze-drying and kneading method were investigated. Solubility of NPX linearly increased (correlation cefficient, 0.995) as $2-HP\betaCD$ concentraction increased, resutling in $A_l$ type phase solubility curve. Inclusion complexes prepared by four different methods were compared by different methods were compared by dfferential scanning calorimetry(DSC). The NPX showed sharp endothemic peak around $156^{\circ}C$ but inclusion complexes by evaporation, freeze-drying and kneading method showed very broad peak without distinct phase transtion temperature. In contrast, inclusion complex prepared by coprecipitation method resulted in detectable peak around $156^{\circ}C$ which is similar to NPX, suggesting incoplete formation of indusion co plex. Dissolution rate of inclusion complexes prepared by evaporation, frezz-drying and kneding except coprecipitation method was largely enhanced in the simultaed gastric and intestinal fluid when compared to NPX powder and commercial $NA-XEN^\registered$tablet. However, about 65% of NPX in gstric fluid. in case of inclusion complex prepared by coprecipitation method, formation of inclusion complex appeared to be incoplete, resulting in no marked enhancement of dissolution rate. From these findings, inclusion complexes of poorly water-soluble NPX with $2-HP\betaCD$ were useful to increase soubility and dissolution rate, resting in enhancement of bioavailability and minimization of gastrointestinal toxicity of drug upon oral administration of inclusion complex.

• Economic and Environmental Geology
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• v.18 no.4
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• pp.331-342
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• 1985

The Dongbo tungsten-molybdenum deposits are fissure-filling veins emplaced in granites of late Cretaceous age. Integrated field, mineralogic and fluid inclusion studies were undertaken to illuminate the characters and origin of the ore deposits. Mineral paragenesis is complicated by repeated fracturing, but four distinct depositional stages can be recognized; (I) tungsten-molybdenum minerals-quartz-chlorite stage, (II) iron-oxide and sulfides-quartz stage, (III) iron -oxide-base metal sulfides-sulfosalts-quartz-carbonates stage, (IV) barren rhodochrosite-zeolite stage. Fluid inclusion studies were carried out for stage I quartz and stage III quartz, sphalerite and calcite. Fluid inclusion studies reveals highly systematic trends of homogenization temperature and salinity throughout the mineralization. Ore fluids during stage I were complex, NaCl rich brine and salinity reached values as high as 34.4 weight percent equivalent NaCl, but the later ore fluids were more dilute and reached to 9.7 weight percent equivalent NaCl during stage III. Intermittent boiling of ore fluid during stage I is indicated by the fluid inclusions in stage I quartz. Depositional temperatures and pressures during stage I range from $520^{\circ}C$ to $265^{\circ}C$and from 600 to 400 bars. Homogenization temperatures of the stage III quartz, sphalerite and calcite range from $305^{\circ}C$ to $190^{\circ}C$. Fluid inclusion data from the Dongbo mine are nearly similar to those from other hydrothermal tungsten deposits in the Kyeongsang basin. Depositional temperature and salinity of ore fluids during precipitation of tungsten-molybdenum minerals in Dongbo mine were much higher, but $CO_2$ contents were much lower than those from hydrothermal tungsten-molybdenum deposits of late Cretaceous plutonic association in central parts of Korean peninsula.

• Economic and Environmental Geology
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• v.18 no.3
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• pp.225-237
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• 1985

Mineralization of Daehwa and Donsan W-Mo deposits can be devided into three distinct depositional stages on the basis of mineral paragenesis and flnid inclusion studies; stage I, deposition of oxides and silicates ; stage II, deposition of base-metal sulfides and sulfosalts with carbonates; stage III, deposition of barren calcite and fluorite. Tungsten, molybdenum and tin mineralization occurred in stage I. Fluid inclusion studies reveal that ore fluid of stage I were homogeneous $H_2O-CO_2$ fluids containing 3.5~14.6 mol % $CO_2$. Minimum temperature and pressure of stage I ore fluids were $240^{\circ}C$ and 500 bars respectively. Salinities of aqueous type I inclusions in minerals of stage I range from 3.7 to 7.6 wt. % equi. NaCl. whereas those of $CO_2$-containing type III inclusions range from 0.3 to 4.4 wt. %. Temperatures of stage II ore fluids range from 200 to $305^{\circ}C$ on the whole and salinities were in the range of 3.2~7.2 wt. %. Homogenization temperatures of fluid inclusions in calcite and fluorite of stage III range from 114 to $186^{\circ}C$ and salinities were in the range of 0.9~4.3 wt. %. Sulfur fugacities during stage II deduced from mineral assemblages and tamperature data from fluid inclusions declined from earlier to later in the range of $10^{-11}{\sim}10^{-18}atm$. Fluid inclusion evidences suggest that the dominance of $CO_2$ in ore fluid during W-Mo mineralization is the characteristic features of Cretaceous W-Mo deposits of central district of Korea compared to those of Kyeongsang basin district.

• Journal of Pharmaceutical Investigation
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• v.25 no.1
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• pp.31-36
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• 1995

Solid dispersions and inclusion complex were prepared for the enhancement of solubility and dissolution rate of poorly water-soluble ibuprofen(IPF) as a model drug. Polyethylene glycol 4000(PEG4000) and polyvinylpyrrolidone(PVP) were used for the preparation of solid dispersion. $2-Hydroxypropyl-{\beta}-cyclodextrin(2-HP{\beta}CD)$ was also used for the preparation of inclusion complex. The solubility of IPF increased as the concentration of PEG4000, PVP and $2-HP{\beta}CD$ increased. Solubilization capacity of $2-HP{\beta}CD$ was increased about 10 times when compared to PEG 4000 and PVP. The dissolution rate of drug from solid dispersions and inclusion complex in the simulated gastric fluid was enhanced when compared to pure IPF and commercial $BR4^{\circledR}$ tablet as a result of improvement of solubility. In case of solid dispersions, dissolution rate of drug was proportional to polymer concentration in the formulation. The marked enhancement of dissolution rate of drug by inclusion complexation with $2-HP{\beta}CD$ was noted. However, dissolution rate of drug from solid dispersions and inclusion complex in the simulated intestinal fluid was not significant because IPF was readily soluble in that condition. From these findings, water-soluble polymers and cyclodextrin were useful to improve solubility and dissolution rate of poorly water-soluble drugs. However, easiness and reliability of preparation method, scale-up and cost of raw materials must be considered for the practical application of solid dispersion and inclusion complex in pharmaceutical industry.

• Proceedings of the KSEEG Conference
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• 1999.04a
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• pp.153-153
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• 1999