• Journal of Korean Society of Environmental Engineers
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• v.31 no.2
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• pp.79-89
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• 2009

Naphthalene is a volatile, hydrophobic, and possibly carcinogenic compound that is known to have a severe detrimental effect to aquatic ecosystem. Our research examined the effects of various operating conditions (temperature, pH, initial concentration, and frequency and type of ultrasound) on the sonochemical degradation of naphthalene and OH radical production. The MDL (Method detection limit) determined by LC/FLD (1200 series, Agilient) using C-18 reversed column is measured up to 0.01 ppm. Naphthalene vapor produced from ultrasound irradiation was detected under 0.05 ppm. Comparison of naphthalene sonodegradion efficiency tested under open and closed reactor cover fell within less than 1% of difference. Increasing the reaction temperature from $15^{\circ}C$ to $40^{\circ}C$ resulted in reduction of naphthalene degradation efficiency ($15^{\circ}C$: 95% ${\rightarrow}$ $40^{\circ}C$: 85%), and altering pH from 12 to 3 increased the effect (pH 12: 84% ${\rightarrow}$pH 3: 95.6%). Pseudo first-order constants ($k_1$) of sonodegradation of naphthalene decreased as initial concentration of naphthalene increased (2.5 ppm: $27.3{\times}10^{-3}\;min^{-3}\;{\rightarrow}$ 10 ppm : $19.3{\times}10^{-3}\;min^{-3}$). Degradation efficiency of 2.5 ppm of naphthalene subjected to 28 kHz of ultrasonic irradiation was found to be 1.46 times as much as when exposed under 132 kHz (132 kHz: 56%, 28 kHz: 82.7%). Additionally, its $k_1$ constant was increased by 2.3 times (132 kHz: $2.4{\times}10^{-3}\;min^{-1}$, 28 kHz: $5.0{\times}10^{-3}\;min^{-1}$). $H_2O_2$ concentration measured 10 minutes after the exposure to 132 kHz of ultrasound, when compared with the measurement under frequency of 28 kHz, was 7.2 times as much. The concentration measured after 90 minutes, however, showed the difference of only 10%. (concentration of $H_2O_2$ under 28 kHz being 1.1 times greater than that under 132 kHz.) The $H_2O_2$ concentration resulting from 2.5 ppm naphthalene after 90 minutes of sonication at 24 kHz and 132 kHz were lower by 0.05 and 0.1 ppm, respectively, than the concentration measured from the irradiated M.Q. water (no naphthalene added.) Degradation efficiency of horn type (24 kHz) and bath type (28 kHz) ultrasound was found to be 87% and 82.7%, respectively, and $k_1$ was calculated into $22.8{\times}10^{-3}\;min^{-1}$ and $18.7{\times}10^{-3}\;min^{-1}$ respectively. Using the multi- frequency and mixed type of ultrasound system (28 kHz bath type + 24 kHz horn type) simultaneously resulted in combined efficiency of 88.1%, while $H_2O_2$ concentration increased 3.5 times (28 kHz + 24 kHz: 2.37 ppm, 24 kHz: 0.7 ppm.) Therefore, the multi-frequency and mixed type of ultrasound system procedure might be most effectively used for removing the substances that are easily oxidized by the OH radical.

• Tuberculosis and Respiratory Diseases
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• v.41 no.3
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• pp.231-238
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• 1994

Backgroud: Since the demonstration of the fact that vascular relaxation by acetylcholine(Ach) results from the release of relaxing factor from the endothelium, the identity and physiology of this endothelium-derived relaxing factor(EDRF) has been the target for many researches. EDRF has been identified as nitric oxide(NO). With the recent evidences that EDRF is an important mediator of vascular tone, there have been increasing interests in defining the role of the EDRF as a potential mediator of hypoxic pulmonary vasoconstriction. But the role of EDRF in modulating the pulmonary circulation is not compeletely clarified. To investigate the endothelium-dependent pulmonary vasodilation and the role of EDRF during hypoxic pulmonary vasoconstriction, we studied the effects of $N^G$-monomethyl-L-arginine(L-NMMA) and L-arginine on the precontracted pulmonary arterial rings of the rat in normoxia and hypoxia. Mothods: The pulmonary arteries of male Sprague Dawley(300~350g) were dissected free of surrounding tissue, and cut into rings. Rings were mounted over fine rigid wires, in organ chambers filled with 20ml of Krebs solution bubbled with 95 percent oxygen and 5 percent carbon dioxide and maintained at $37^{\circ}C$. Changes in isometric tension were recorded with a force transducer(FT.03 Grass, Quincy, USA) Results: 1) Precontraction of rat pulmonry artery with intact endothelium by phenylephrine(PE, $10^{-6}M$) was relaxed completely by acetylcholine(Ach, $10^{-9}-10^{-5}M$) and sodium nitroprusside(SN, $10^{-9}-10^{-5}M$), but relaxing response by Ach in rat pulmonary artery with denuded endothelium was significantly decreased. 2) L-NMMA($10^{-4}M$) pretreatment inhibited Ach($10^{-9}-10^{-5}M$)-induced relaxation, but L-NMMA ($10^{-4}M$) had no effect on relaxation induced by SN($10^{-9}-10^{-5}M$). 3) Pretreatment of the L-arginine($10^{-4}M$) significantly reversed the inhibition of the Ach ($10^{-9}-10^{-5}M$)-induced relaxation caused by L-NMMA($10^{-4}M$) 4) Pulmonary arterial contraction by PE($10^{-6}M$) was stronger in hypoxia than normoxia but relaxing response by Ach($10^{-9}-10^{-5}M$) was decreased, 5) With pretreatment of L-arginine($10^{-4}M$), pulmonary arterial relaxation by Ach($10^{-9}-10^{-5}M$) in hypoxia was reversed to the level of relaxation in normoxia. Conclusion: It is concluded that rat pulmonary arterial relaxation by Ach is dependent on the intact endothelium and is largely mediated by NO. Acute hypoxic pulmonary vasoconstriction is related to the suppression on NO formation in the vascular endothelium.

• Tuberculosis and Respiratory Diseases
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• v.43 no.6
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• pp.945-953
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• 1996

Background : Many acute and chronic lung diseases including pneumoconiosis are characterized by the presence of increased numbers of activated macrophages. These macrophages generate several inflammatory cell chemoattractants, by which neutrophil migrate from vascular compartment to the alveolar space. Recruited neutrophils secrete toxic oxygen radicals or proteolytic enzymes and induce inflammatory response. Continuing inflammatory response results in alteration of the pulmonary structure and irreversible fibrosis. Recently, a polypeptide with specific neutrophil chemotactic activity, interleukin-8(IL-8), has been cloned and isolated from a number of cells including : monocytes, macrophages and fibroblasts. IL-1 and/or TNF-${\alpha}$ preceded for the synthesis of IL-8, and we already observed high level of IL-1 and TNF-${\alpha}$ in the pneumoconioses. So we hypothesized that IL-8 may be a central role in the pathogenesis of pneumoconiosis. In order to evaluate the clinical utility of IL-8 as a biomarker in the early diagnosis of pneumoconiosis, we investigated the increase of IL-8 in the pneumoconiotic patient and the correlation between IL-8 level and progression of pneumoconiosis. Method : We measured IL-8 in the serum of 48 patients with pneumoconiosis and 16 persons without dust exposure history as a control group. Pneumoconiotic cases were divided into 3 groups according to ILO Classification : suspicious group(n=16), small opacity group(n=16) and large opacity group(n=16). IL-8 was measured by a sandwich enzytne immunoassay technique. All data were expressed as the $mean{\pm}standard$ deviation. Results: 1) The mean value of age was higher in the small opacity and large opacity group than comparison group, but smoking history was even. Duration of dust exposure was not different among 3 pneumoconiosis groups. 2) IL-8 level was $70.50{\pm}53.63pg/m{\ell}$ in the suspicious group, $107.50{\pm}45.88pg/m{\ell}$ in the small opacity group, $132.50{\pm}73.47pg/m{\ell}$ in the large opacity group and $17.85{\pm}33.85pg/m{\ell}$ in the comparison group. IL-8 concentration in all pneumoconiosis group was significant higher than that in the comparison group(p<0.001). 3) IL-8 level tended to increase with the progression of pneumoconiosis. Multiple comparison test using Anova/Scheffe analysis showed a significant difference between suspicious group and large opacity group(p<0.05). 4) The level of IL-8 was correlated with the progression of pneumoconiosis(r=0.4199, p<0.05). Conclusion : IL-8 is thought to be a good biomarker for the early diagnosis of pneumoconiosis.

• Economic and Environmental Geology
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• v.25 no.4
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• pp.417-433
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• 1992

Lead-zinc-copper deposits of the Jeonheung and the Oksan mines around Euiseong area occur as hydrothermal quartz and calcite veins that crosscut Cretaceous sedimentary rocks of the Gyeongsang Basin. The mineralization occurred in three distinct stages (I, II, and III): (I) quartz-sulfides-sulfosalts-hematite mineralization stage; (II) barren quartz-fluorite stage; and (III) barren calcite stage. Stage I ore minerals comprise pyrite, chalcopyrite, sphalerite, galena and Pb-Ag-Bi-Sb sulfosalts. Mineralogies of the two mines are different, and arsenopyrite, pyrrhotite, tetrahedrite and iron-rich (up to 21 mole % FeS) sphalerite are restricted to the Oksan mine. A K-Ar radiometric dating for sericite indicates that the Pb-Zn-Cu deposits of the Euiseong area were formed during late Cretaceous age ($62.3{\pm}2.8Ma$), likely associated with a subvolcanic activity related to the volcanic complex in the nearby Geumseongsan Caldera and the ubiquitous felsite dykes. Stage I mineralization occurred at temperatures between > $380^{\circ}C$ and $240^{\circ}C$ from fluids with salinities between 6.3 and 0.7 equiv. wt. % NaCl. The chalcopyrite deposition occurred mostly at higher temperatures of > $300^{\circ}C$. Fluid inclusion data indicate that the Pb-Zn-Cu ore mineralization resulted from a complex history of boiling, cooling and dilution of ore fluids. The mineralization at Jeonheung resulted mainly from cooling and dilution by an influx of cooler meteoric waters, whereas the mineralization at Oksan was largely due to fluid boiling. Evidence of fluid boiling suggests that pressures decreased from about 210 bars to 80 bars. This corresponds to a depth of about 900 m in a hydrothermal system that changed from lithostatic (closed) toward hydrostatic (open) conditions. Sulfur isotope compositions of sulfide minerals (${\delta}^{34}S=2.9{\sim}9.6$ per mil) indicate that the ${\delta}^{34}S_{{\Sigma}S}$ value of ore fluids was ${\approx}8.6$ per mil. This ${\delta}^{34}S_{{\Sigma}S}$ value is likely consistent with an igneous sulfur mixed with sulfates (?) in surrounding sedimentary rocks. Measured and calculated hydrogen and oxygen isotope values of ore-forming fluids suggest meteoric water dominance, approaching unexchanged meteoric water values. Equilibrium thermodynamic interpretation indicates that the temperature versus $fs_2$ variation of stage I ore fluids differed between the two mines as follows: the $fs_2$ of ore fluids at Jeonheung changed with decreasing temperature constantly near the pyrite-hematite-magnetite sulfidation curve, whereas those at Oksan changed from the pyrite-pyrrhotite sulfidation state towards the pyrite-hematite-magnetite state. The shift in minerals precipitated during stage I also reflects a concomitant $fo_2$ increase, probably due to mixing of ore fluids with cooler, more oxidizing meteoric waters. Thermodynamic consideration of copper solubility suggests that the ore-forming fluids cooled through boiling at Oksan and mixing with less-evolved meteoric waters at Jeonheung, and that this cooling was the main cause of copper deposition through destabilization of copper chloride complexes.

• Applied Biological Chemistry
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• v.17 no.3
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• pp.149-176
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• 1974

Eight substituted diphenyl ether herbicides and some of their photoproducts were studied in terms of solution phase photolysis under simulated environmental conditions by using a Rayonet photochemical reactor. The test compounds absorbed sufficient light energy at the wavelength of 300 nm to undergo various photoreactions. All the photoproducts were confirmed by means of tlc, glc, ir, ms, and/or nmr spectrometry. The results obtained are summarized as follows: Solution phase photolysis of C-6989: An exceedingly large amount of p-nitrophenol formed strongly indicates the readiness of the ether linkage cleavage of this compound as the main reaction in all solvents used. Photoreduction of nitro to amino group(s) and photooxidation of trifluoromethyl to carboxyl group were recognized as minor reactions. Aqueous photolysis of p-nitrophenol: Quinone(0.28%), hydroquinone (0.66%), and p-aminophenol (0.42%) were confirmed as photoproducts, in addition to a relatively small amount of an unknown compound. The mechanisms of formation of these products were proposed to be the nitro-nitrite rearrangement via $n{\rightarrow}{\pi}^*$ excitation and the photoreduction through hydrogen abstractions by radicals, respectively. Solution phase photolysis of Nitrofen: Photochemical reduction leading to the p-amino derivative was the main reaction in n-hexane. In aqueous solution, the photoreduction of nitro to amino group and hydroxylation predominated over the ether linkage cleavage. Nucleophilic displacement of the nitro group by hydroxide ion and replacement of chlorine substituents by hydroxyl group or, to a lesser extent, hydrogen were also observed as minor reactoins. Solution phase photolysis of MO-338: Photoreduction of the nitro to amino group was marked in the n-hexane solution photolysis. In the aqueous solution, photoreduction of the nitro substituent and hydroxylation were the main reactions with replacement of chlorine substituents by the hydroxyl group and hydrogen, and cleavage of the ether linkage as minor reactions. Photolyses of MC-4379, MC-3761, MC-5127, MC-6063, and MC-7181 in n-hexane and cyclohexane: Photoreduction of the nitro group leading to the corresponding amino derivative and replacement of one of the halogen substituents by hydrogen from the solvent used were the key reactions in each compound. Aqueous photolysis of MC-4379: Cleavage of the ether linkage, replacement of the carboxymethyl by hydroxyl group, hydroxylation, and replacement of the nitro by hydroxy group were prominent with photoreduction and dechlorination as minor reactions. Aqueous photolysis of MC-3761: Cleavage of the ether linkage, replacement of the carboxymethyl by hydroxyl group, and photoreduction followed by hydroxylation were the main reactions. Aqueous photolysis of MC-5127: Replacement of carboxyethyl by hydrogen was predominant with ether linkage cleavage, photoreduction, and dechlorination as minor reactions. It was obvious that the decarboxyethylation proceeded more readily than decarboxymethylation occurring in the other compounds. Aqueous photolysis of MC-6063: Cleavage of the ether linkage and photodechlorination were the main reactions. Aqueous photolysis of MC-7181: Replacement of the carboxymethyl group by hydrogen and monodechlorination were the remarkable reactions. Cleavage of the ether linkage and hydroxylation were thought to be the minor reactions. Aqueous photolysis of 3-carboxymethyl-4-nitrophenol: The photo-induced Fries rearrangement common to aromatic esters did not appear to occur in the carboxymethyl group of this type of compound. Conversion of nitro to nitroso group was the main reaction.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.17-23
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• 1976

In order to investigate the fate of nitrogen in the paddy soil, Suchang, Hwasoon and Susan soil which have different properties, were treated with several nitrogen fertilizers such as ammonium chloride, ammonium sulfate, urea and SCU (sulfur-coated urea), and incubated under water-logged condition in $30^{\circ}C$ incubator. $NH_4-N$, $NO_3-N$, $Fe^{++}$ and pH in soil and stagnant water, were determined at 10, 20, 30, 40 and 50 days after incubation. The obtained results were summarized as follows: 1. The effect of rising temperature was increased in order of Hwasoon>Suchang>Susan and the effect of air drying soil was risen in order of Susan>Hwasoon>Suchang, while the rate of ammonication was in order of Susan>Suchang>Hwasoon. 2. The changes of $NH_4-N$ in stagnant water was dependent upon the nitrogen concentration of $NH_4Cl$ and $(NH_4)SO_4$ plat was high and decreased after 30 days incubation, but increased after 40 days and then decreased again. In contrast with the above, $NH_4-N$ concentration of urea and SCU plot was low but the change showed slightly through the incubation period. 3. Accumulation of $NH_4-N$ in the oxidative layer of the $NH_4Cl$ and $(NH_4)_2SO_4$ plot was higher than that of urea and SCU plot and $NH_4-N$ content was decreased with the incubation period. The change of $NH_4-N$ in the reductive layer showed the same pattern. 4. The changes of $NO_3-N$ in the stagnant water were different according to soil properties and nitrogen fertilizer. $NO_3-N$ concentration in stagnant water of urea and SCU plot was higher than in the $NH_4-Cl$ $(NH_4)_2SO_4$ plot and nearly disappeared after 30 to 40 days incubation. 5. The $NO_3-N$ concentration in the oxidative layer of soil was higher than reductive layer. The pattern of change was different in accordance with soil properties and nitrogen fertilizers. In general, nitrification in urea and SCU plot was more increased than $(NH_4)_2SO_4$ plot. In reductive layer, the concentration of $NO_3-N$ was very low until 30 days incubation and thereafter increased slightly. 6. Upon the concentration of $NH_4-N$ and $NO_3-N$ in stagnant water and soil, it was assumed that denitification of urea and SCU plot was higher than $NH_4Cl$ and $(NH_4)_2SO_4$ plot and denitrified nitrogen in incubation period was above 50%.

• Korean Journal of Heritage: History & Science
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• v.41 no.1
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• pp.5-19
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• 2008

Thirty six samples of Western asia glass vessel shards which were excavated from South Mound of Hwangnamdaechong were each measured for thickness, pore size and specific gravity and analyzed for ten major compositions and thirteen trace elements. The glass samples with colorless, greenish blue and dark purple blue were well classified by principal component analysis(PCA). All glass shards of Hwangnamdaechong belonged to Soda glass system ($Na_2O-CaO-SiO_2$) which have the range of 14~17% $Na_2O$ and 5~6% CaO. The corelation coefficients of (MgO, $K_2O$) and (MnO, CuO) showed above 0.90. The concentrations of thirteen trace elements apparently differentiated from colorless, greenish blue and dark blue glasses. We found that thirteen trace elements were very important indices for studying raw material of glass and the origin of glass making. Colorless glass : The specific gravity is $1.50{\pm}0.04$. Circle or oval circle pores are observed with regular direction in internal zone and the longest one is about 0.35 mm. The raw material of sodium must be the plant ash because sodium glasses contain HCLA(High CaO, Low $Al_2O_3$) and HMK(high MgO, high $K_2O$) and suggested to Sasanian glass. The total amount of coloring agent of colorless glass is below 1 % which is too small to attribute to the color. Greenish blue glass : The specific gravity is $1.58{\pm}0.04$. The fine pores which are 0.1~0.2mm are dispersed in internal zone. Sodium glasses are distributed to HCLA and HMK. Therefore the greenish blue glass also have used plant ash for raw material of sodium with the same as colorless glass. It was also suggested to the glass of Sasanian. The total amount of coloring agent of greenish blue glass is about 4% under the influence of working MnO, $Fe_2O_3$ and CuO. Dark purple blue glass : The specific gravity is $1.48{\pm}0.19$. There are rarely pores in internal zone. They are distributed to HCLA and LMK(Low MgO, Low $K_2O$) and suggested to Roman glass. The raw material of sodium is estimated to natron. The total amount of coloring agents of greenish blue is about 3% by $Fe_2O_3$ and CuO. These studies for western asia glass shards from South Mound of Hwangnamdaechong could be used in the future as the standard data which could be compared with those of other several graves in Korea and dispersed in foreign areas.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.1
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• pp.75-81
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• 2019

Purpose: Helmet type bolus for 3D printer is being manufactured because of the disadvantages of Bolus materials when photon beam is used for the treatment of scalp malignancy. However, PLA, which is a used material, has a higher density than a tissue equivalent material and inconveniences occur when the patient wears PLA. In this study, we try to treat malignant scalp tumors by using M3 wax helmet with 3D printer. Methods and materials: For the modeling of the helmet type M3 wax, the head phantom was photographed by CT, which was acquired with a DICOM file. The part for helmet on the scalp was made with Helmet contour. The M3 Wax helmet was made by dissolving paraffin wax, mixing magnesium oxide and calcium carbonate, solidifying it in a PLA 3D helmet, and then eliminated PLA 3D Helmet of the surface. The treatment plan was based on Intensity-Modulated Radiation Therapy (IMRT) of 10 Portals, and the therapeutic dose was 200 cGy, using Analytical Anisotropic Algorithm (AAA) of Eclipse. Then, the dose was verified by using EBT3 film and Mosfet (Metal Oxide Semiconductor Field Effect Transistor: USA), and the IMRT plan was measured 3 times in 3 parts by reproducing the phantom of the head human model under the same condition with the CT simulation room. Results: The Hounsfield unit (HU) of the bolus measured by CT was $52{\pm}37.1$. The dose of TPS was 186.6 cGy, 193.2 cGy and 190.6 cGy at the M3 Wax bolus measurement points of A, B and C, and the dose measured three times at Mostet was $179.66{\pm}2.62cGy$, $184.33{\pm}1.24cGy$ and $195.33{\pm}1.69cGy$. And the error rates were -3.71 %, -4.59 %, and 2.48 %. The dose measured with EBT3 film was $182.00{\pm}1.63cGy$, $193.66{\pm}2.05cGy$ and $196{\pm}2.16cGy$. The error rates were -2.46 %, 0.23 % and 2.83 %. Conclusions: The thickness of the M3 wax bolus was 2 cm, which could help the treatment plan to be established by easily lowering the dose of the brain part. The maximum error rate of the scalp surface dose was measured within 5 % and generally within 3 %, even in the A, B, C measurements of dosimeters of EBT3 film and Mosfet in the treatment dose verification. The making period of M3 wax bolus is shorter, cheaper than that of 3D printer, can be reused and is very useful for the treatment of scalp malignancies as human tissue equivalent material. Therefore, we think that the use of casting type M3 wax bolus, which will complement the making period and cost of high capacity Bolus and Compensator in 3D printer, will increase later.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.3
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• pp.185-197
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• 2023

The Gubong Au-Ag deposit consists of eight lens-shaped quartz veins. These veins have filled fractures along fault zones within Precambrian metasedimentary rock. This has been one of the largest deposits in Korea, and is geologically a mix of orogenic-type and intrusion-related types. Korea Mining Promotion Corporation drilled into a quartz vein (referred to as the No. 6 vein) with a width of 0.9 m and a grade of 27.9 g/t Au at a depth of -728 ML by drilling (No. 90-12) in the southern site of the deposit, To further investigate the potential redevelopment of the No. 6 vein, another drilling (No. 04-1) was carried out in 2004. In 2004, samples (wallrock, wallrock alteration and quartz vein) were collected from the No. 04-1 drilling core site to study the occurrence and chemical composition of Ti-bearing minerals (ilmenite, rutile). Rutile from mineralized zone at a depth of -275 ML occur minerals including K-feldspar, biotite, quartz, calcite, chlorite, pyrite in wallrock alteration zone. Ilmenite and rutile from ore vein (No. 6 vein) at a depth of -779 ML occur minerals including white mica, chlorite, apatite, zircon, quartz, calcite, pyrrhotite, pyrite in wallrock alteration zone and quartz vein. Based on mineral assemblage, rutile was formed by hydrothermal alteration (chloritization) of Ti-rich biotite in the wallrock. Chemical composition of ilmenite has maximum values of 0.09 wt.% (HfO₂), 0.39 wt.% (V₂O₃) and 0.54 wt.% (BaO). Comparing the chemical composition of rutile at a depth -275 ML and -779 ML, Rutile at a depth of -779 ML is higher contents (WO₃, FeO and BaO) than rutile at a depth of -275 ML. The substitutions of rutile at a depth of -275 ML and -779 ML are as followed : rutile at a depth of -275 ML Ba²⁺ + Al³⁺ + Hf⁴⁺ + (Nb⁵⁺, Ta⁵⁺) ↔ 3Ti⁴⁺ + Fe²⁺, 2V⁴⁺ + (W⁵⁺, Ta⁵⁺, Nb⁵⁺) ↔ 2Ti⁴⁺ + Al³⁺ + (Fe²⁺, Ba²⁺), Al³⁺ + V⁴⁺+ (Nb⁵⁺, Ta⁵⁺) ↔ 2Ti⁴⁺ + 2Fe²⁺, rutile at a depth of -779 ML 2 (Fe²⁺, Ba²⁺) + Al³⁺ + (W⁵⁺, Nb⁵⁺, Ta⁵⁺) ↔ 2Ti⁴⁺ + (V⁴⁺, Hf⁴⁺), Fe²⁺ + Al³⁺ + Hf ⁴⁺ + (W⁵⁺, Nb⁵⁺, Ta⁵⁺) ↔ 2Ti⁴⁺ + V⁴⁺ + Ba²⁺, respectively. Based on these data and chemical composition of rutiles from orogenic-type deposits, rutiles from Gubong deposit was formed in a relatively oxidizing environment than the rutile from orogenictype deposits (Unsan deposit, Kori Kollo deposit, Big Bell deposit, Meguma gold-bearing quartz vein).

• Korean Journal of Agricultural Science
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• v.30 no.1
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• pp.31-40
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• 2003

A research has been done for growing characteristics of Korean ginseng in Geumsan of Chungnam Province. It had been made to determine the transitional element concentrations of the rocks, divided by biotitic granite(GR) and phyllite(PH). The physical and chemical properties of their weathering soils and ginseng nursery soils were analyzed. The texture in the GR weathering and ginseng nursery soils were sandy clay, and the texture of the PH weathering and ginseng nursery soils were heavy or silty clay. The bulk densities of the GR and PH weathering soils were $1.21{\sim}1.32g/cm^3$ and $1.26{\sim}1.38g/cm^3$, respectively. Also, the bulk densities of the GR and PH ginseng nursery soils were $1.02{\sim}1.10g/cm^3$, respectively. The pH (4.80) of the GR weathering soil were lower than the pH of the PH(5.34) weathering soil. The pH in the 2 year and 4 year-ginseng nursery soil of the GR were 4.39 and 4.40. In addition, those of the PH were 5.24 and 5.34, respectively. The difference in pH of the two nursery soils could be from the pH difference between the two parent materials. The organic matter contents of the GR weathering soils(0.24%) were higher than those of the PH(1.02%) weathering soils. The organic matter of the 2 and 4 year-ginseng GR nursery soils were 0.87% and 1.52%, and of the PH nursery soils were 2.06% and 2.96%, respectively. The total nitrogen contents of the GR weathering soils were 259.43ppm and of the PH weathering soils were 657.22ppm. Those of 2 and 4 year-ginseng GR nursery soils were 588.04ppm and 657.22ppm and those of the PH nursery soils were 1037.72ppm and 1227.96ppm, respectively. The nitrate and ammonium contents of the GR weathering soils were the extremely small, and those of the PH weathering soils were 6.7ppm and 9.94ppm. Those of 2 year-ginseng GR nursery soils(223.09ppm and 26.96ppm) were higher than those of PH(19.46ppm and 8.23ppm) nursery soils. And those of 2 year-ginseng PH nursery soils(14.22ppm and 16.84ppm) were lower than those of PH(306.93ppm, 34.21ppm) nursery soils. The difference was due to fertilizer types and more deposits of nitrate after oxidation of ammonium. The phosphate contents of the GR and PH weathering soils were 14.41ppm and 38.60ppm. Those of GR 2 and 4 year-ginseng nursery soils were 46.89ppm and 102.44ppm and those of the PH nursery soils were 147.04ppm and 38.60ppm. The cation exchange capacities of the GR weathering soils were 12.34me/100g and those of the PH weathering soils were 15.40me/100g. Those of 2 and 4 year-ginseng GR nursery soils were 15.80me/100g and 7.70me/100g and those of PH nursery soils were 12.14me/100g and 12.83me/100g. All of exchangeable cation($K^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$) contents in the nursery soils were higher than those in the weathering soils. The $SO_4{^2-}$ contents of the weathering soils in both of the GR(5.98ppm) and PH(9.94ppm) were higher than those of the GR and PH ginseng nursery soils. The $Cl^-$) contents of the GR and PH weathering soils were a very small and those of the nursery soils(2-yr GR: 39.06ppm, 4-yr GR: 273.43ppm, 2-yr PH: 66.41ppm, 4-yr PH: 406.24ppm) were high because of fertilizer inputs.