• Economic and Environmental Geology
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• v.38 no.2 s.171
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• pp.187-196
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• 2005

Structural sites which cations can occupy in garnet structure are centers of the tetrahedron, octahedron, and distorted cube sharing edges with the tetrahedron and octahedron. Among them, the size of cation occuping at tetrahedral site (the center of tetrahedron) is closely related with the size of a unit cell of garnet. Accordingly, garnet containing iron with relative large ionic radii in tetrahedral site can be considered as a promising matrix for the immobilization of the elements with large ionic radii, such as actinides in radioactive wastes. We synthesized several garnets with the batch composition of $Ca_{1.5}GdCe_{0.5}ZrFeFe_3O_{12}$, and studied their properties and phase relations under various conditions. Mixed samples were fabricated in a pellet form under a pressure of $200{\~}400{\cal}kg/{\cal}cm^2$ and were sintered in the temperature range of $1100\~1400^{\circ}C$ in air and under oxygen atmospheres. Phase identification and chemical analysis of synthesized samples were conducted by XRD and SEM/EDS. In results, garnet was obtained as the main phase at $1300^{\circ}C$, an optimum condition in this system, even though some minor phases like perovskite and unknown phase were included. The compositions of garnet and perovskite synthesized from the batch composition of $Ca_{1.5}GdCe_{0.5}ZrFeFe_3O_{12}$ were ranged $[Ca_{l.2-1.8}Gd_{0.9-1.4}Ce_{0.3-0.5}]^{VIII}[Zr_{0.8-1.3}Fe_{0.7-1.2}]^{VI}[Fe_{2.9-3.1}]^{IV}O_{12}$ and $Ca_{0.1-0.5}Gd_{0.0-0.8}Ce_{0.1-0.5}\;Zr_{0.0-0.2}Fe_{0.9-1.1}O_3$, respectively. Ca content was exceeded and Ce content was depleted in the 8-coordinated site, comparing to the initial batch composition. This phenomena was closely related to the content of Zr and Fe in the 6-coordinated site.

• Korean Journal of Poultry Science
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• v.12 no.1
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• pp.25-30
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• 1985

In order to observe an effect of the components of rice straw on the utilization of nutrient in chicks, the rice straw of 100g were digested in 800$m\ell$ of distilled water or 0.25N NaClO$_2$ at 135 C and in the pressure of 3.2kg/$\textrm{cm}^2$ by autoclave during 30, 60 and 120 minutes (water or NaClO$_2$-30, 60 and 120- RS). The contents of neutral detergent fiber(NDF), acid detergent fiber (ADF) and lignin were analysed in the washed and dried rice straw meal. Hatched single comb white Leghorn male chicks were fed with a commercial chick mash for the first 10 days and five kinds of experimetal diets for the next 8 days which contained 17.0% of wheat bran (basal), cellulose(cotton meal), nontreated RS, water-30-RS and NaClO$_2$ 30-RS, respectively. The water-30, 60 and 120-RS baa leased 9.7, 12.1 and 13.3% of dry matter, respectively, while NaClO$_2$-30-RS had similar contents of dry matter loss with those of water-30-RS, and NaClO$_2$-60 and 120-RS had tossed 1.5 times of dry matter comparing with those of water-60 and 120-RS, respectively. And the dry matter loss of the water-RS or NaClO$_2$-RS was mainly originated front the extractable cell contents and hemicellulose of the non-treated RS. Birds fed water-30-RS diets had higher body weight gain and lower feed conversion than those of birds fed non-treated and NaClO$_2$-30-RS diets during 8 days of experimental feeding. Also nitrogen balance and retention rate of birds fed water -30-RS was higher comparing with those of birds non-treated and NaClO$_2$-30-RS. And digestibility of crude fat had been shown a highering trend in birds water-30-RS. The rate of metabolizable energy (MEn) to gross energy (GE) of birds fed non-treated RS, water-30-RS and NaClO$_2$30-RS diets were 71.9, 72.9 and 70.4%, respectively, and energy intake per metaboic body size (kg 0.75) were reached to 307.3, 296.2 and 291.4 kcal per day, respectively. And daily protein retention per kg 0.75 were 1.647, 1.969 and 1.560g, respectively. Then 30.56kcal of MEn required for 1 g of protein retention in birds fed water-30-RS, which was lower thu 36.90 and 37.56 kcal of birds fed non-treated and NaClO$_2$-30- RS, respectively. The results seems to indicate that non-treated rice straw had a substance or characters which affect the energy unilization or protein retention of diets and which will be eliminated by boiling in water.

• Journal of Soil and Groundwater Environment
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• v.12 no.2
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• pp.9-19
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• 2007

This study investigated the interaction between groundwater and stream water systems, which is caused by the artificial weir on streambed, enforcing external stresses on the groundwater system. The study area is in Nami Natural Recreation Woods located in Chungcheongnam-do Geumsan-gun Nami-myeon Geoncheon-ri. In this study both of hydrophysical methods (hydraulic head) and hyrdochemical investigations (pH, EC, major ion analysis) were applied. In order to identify the relationship between each of study results, cross-correlation analysis is performed. From results of hydrophysical methods, water level fluctuation at BH-14, installed by the weir, shows the double-recession pattern much more frequently and much higher amplitudes than the fluctuation at each of other monitoring wells. Using the results by hydrochemical investigations, hydrochemical properties at BH-14 is similar to the hydrochemical characteristics in stream water. To analyze the interrelationships between the results from each of applied methods, cross-correlation analysis was applied. Results from the correlation analyses, water levels at BH-14 and stream weir showed the highest cross-correlation in hydrophysical aspects. On the other hand, the correlation between stream weir and bridge was the highest in hydrochemical aspects. The difference between the results from each of methods is due that the hydrophysical response at BH-14, such as water level, is induced by the pressure propagation-not with mass transfer, but the hydrochemical interaction, caused by mass transport, takes much more times. In conclusion impermeable artificial weir on streambed changes the interfacial condition between the stream and surrounding aquifers. The induced water flux into the groundwater system during flood period make water level at BH-14 increase instantly and groundwater quality higly similar to the quality of stream water. Referred similarities in both of water level and water quality at BH-14 become much higher when water level at weir grow higher.

• Journal of Chest Surgery
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• v.32 no.7
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• pp.628-636
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• 1999

Background: Recent advances in understanding the anatomy of the complete atrioventricular septal defect(including right-dominant unbalanced atrioventricular septal defect) have led to alternative methods of repairing these defects. Material and Method: From May 1997 to July 1998, 8 consecutive infants(age range, 2 to 28 months, mean body weight 6.0$\pm$2.2 kg) received a single-stage intracardiac repair of the complete atrioventricular septal defect with modified surgical methods. Depending on the specific anatomic structure, the procedure was simplified in 3 patients by a direct closure of the ventricular element of the defect(Group I). Two patients judged unsuitable for direct closure due to a potential left ventricular outflow tract obstruction had received a standard two-patch repair(Group II). The remaining 3 patients with right-dominant unbalanced complete atrioventricular septal defect underwent biventricular repair; to enlarge the orifice of the left atrioventricular valve, the ventricular septal patch was placed slightly more to the right of the ventricular crest, a left sided bridging leaflet was augmented with an autologous pericardial patch, and the leaflet was repaired with a double- orifice(Group III . Result: In all 8 patients, the postoperative echocardiography demonstrated good hemodynamics. Seven patients were weaned from the ventilators after a mean 3$\pm$1 days, and 1 patient was weaned after 24 days due to a reoperation and emphysematous lung problem. A reoperation was performed in 1 patient for progressive left atrioventricular valve regurgitation due to leaflet tearing. There were no early and late mortalities. At the time of the latest review, judging from the echocardiographic criteria, left atrioventricular valve stenosis was mild in 1 patient(mean pressure gradient 6.5 mmHg, 13.5%), left atrioventricular valve regurgitation was absent or grade I in 7 patients(87.5%). The right atrioventricular valve regurgitation was absent or grade I in all 8 patients(100%). Conclusion: Infants with complete atrioventricular septal defect were treated with either a simplified approach with direct closure of the ventricular element of the defect or a modified surgical technique for a right-dominant unbalanced atrioventricular septal defect, depending on the anatomic structure. The results were no operative mortalities and low morbidity.

• Clean Technology
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• v.17 no.1
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• pp.62-68
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• 2011

Hydrodynamic characteristics in multistage annular type fluidized bed (riser: $0.01{\times}0.025{\times}2.8m^3$, J-valve: $0.009{\times}0.015m^2$)were investigated. Glass beads ($d_p=101{\mu}m$, ${\rho}_b=1,590kg/m^3$, $U_{mf}=1.25{\times}10^{-2}m/s$, Geldart classification B) was used as a bed material. Accumulated weight by the electronic balance was measured to determine the solid flow rate in batch-type. In circulation condition, we measured the accumulated weight of particle transported from riser. At the steady state condition, solid circulation rate was calculated from time interval of the heated bed material passing between two thermocouples. Solid flow rate increased with increasing inlet gas velocity ($1.2-2.6U_{mf}$) and the static bed height (z, 0.24-0.68 m) from 2.2 to 23.4 kg/s. However, mean residence time decreased with increasing inlet gas velocity ($1.2-2.6U_{mf}$) and the static bed height (z, 0.24-0.68 m) from 1,438 to 440 s. The solid holdup in the riser was determined by measuring pressure differences according to the riser height. These results showed a similar trend to that of simple exponential decay type except for the top section of the riser. To verify the gas bypassing from top bubbling beds to middle bubbling beds, $CO_2$ gas was injected by tracer gas in constant ratio, and then was measured $CO_2$ concentration in outlet gas by gas chromatography. Gas bypassing occurred below 2.6% which is negligible value.

• Journal of Chest Surgery
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• v.35 no.4
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• pp.290-295
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• 2002

Backgroud: Pneumonectomy carries the possibility of numerous dangerous complications as well as the vast effect the operation itself has on the cardiopulmonary function. Most of operations are done with the insertion of the chest tubes upon completion, but because of the high incidence of pyothorax as its complications, we have tried to analyze and compare the cases without inserting the chest tubes. Material and Method: During a 5 year period from January, 1996 to December 2000, 100 cases, which were operated at the Hanyang University Hospital, were selected using the patient's charts. The age, gender, indication of operation, associated diseases, and operation site(left or right) were classified accordingly and the postoperative complications and mortality were statistically analyzed using the $\chi$ 2-test. After resecting the lung, the intrathoracic pressure was set at -15 ~ -20cm $H_2O$ using the nelaton catheter, and the thoracotomy site was then closed. The gradual collection of the fluid and blood in the thorax of the operated side, as well as the mediastinum location, were observed carefully for 4~5 days postoperatively with the aid of the simple chest x-rays. Result: Of the 100 cases, 16 cases of pulmonary tuberculosis(16%), 81 cases of lung tumor(81%), 2 cases of bronchiectasis(2%), and 1 case of aspergilloma associated bronchiectasis were noted. There were 8 mortality cases(8%), and of the 34 cases(34%), 44 complications were noted. The age, sex, and operation site(left or right) were not statistically significant with the complications. 7 of the 16 cases of pulmonary tuberculosis(44%) and 27 of the 81 cases of lung tumor(33%) had complications, but they were found not to be statistically significant. The increase of the complication rate in the pulmonary tuberculosis patients was 3.86. The evidence of postoperative bleeding was observed in 6 cases with the 3 cases being the pulmonary tuberculosis patients and the 3 cases were others. This shows that the increase in postoperative bleeding in the pulmonary tuberculosis is statistically significant(p=0.019). Of the 100 cases, there were 8 mortality cases(8%), with 5 cases from the 81 cases of the lung tumor group(6.1%), 3 cases from the 16 cases of pulmonary tuberculoses group(18.7%).

• Journal of Chest Surgery
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• v.40 no.12
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• pp.805-810
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• 2007

Background: This paper reviews our experience retrospectively to examine the clinical results and effectiveness of lateral tunnel (LT) and extracardiac conduit (ECC) Fontan procedures at a single institution. Material and Method: One hundred and sixty five Fontan procedures were performed (67 LT and 98 ECC) between January 1996 and December 2006. Preoperative and postoperative hemodynamic values, arrhythmia, hospital and intensive care unit stay, chest tube drain, morbidity and mortality were reviewed. Result: The overall operative mortality in the LT and ECC groups was 4.5% (3) and 2.0% (2), respectively. There was a significant difference in the immediate postoperative transpulmonary gradient (LT $8.5{\pm}2.5$ vs ECC $6.6{\pm}2.4$, p-value<0.001) and central venous pressure (LT $18.3{\pm}3.8$ vs ECC $15.6{\pm}2.4$, p-value=0.001) between the two groups. The mean follow-up in the LT and ECC groups was $74.1{\pm}31.5$ and $38.1{\pm}29.1$ months, respectively. There was one late death. The actuarial survival at 10 years in the LT and ECC groups was 92% and 89%, respectively. In arrhythmia, the ECC patients showed a slightly low incidence but the difference was not statistically significant. Conclusion: Both the LT and ECC Fontan procedures showed comparable early and mid-term outcomes in terms of the surgical morbidity and mortality, postoperative hemodynamics, and mid-term survival. The ECC Fontan procedure reduces the risk of arrhythmia in the follow up period.

• Journal of the Korean earth science society
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• v.22 no.5
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• pp.405-414
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• 2001

Jecheon granite can be divided into two types; porphyritic granite (K-feldspar megacryst bearing) and medium-grained biotite granite. Porphyritic granite, host body of feldspar deposits, is 8${\sim}$11 km in diameter and about 80 $km^{2}$ in area. It mainly contains K-feldspar, plagioclase, biotite and quartz, and magnetite, zircon, sphene and apatite are accessary minerals. Enclosed minerals in K-feldspar megacryst with 3${\sim}$10 cm in diameter are hornblende, plagioclase, quartz, magnetite, apatite, sphene and zircon. Mafic enclaves mainly consisting of hornblende, plagioclase and quartz are frequently observed in porphrytic granite. Medium-grained biotite granite consists of K-feldspar, plagioclase, biotite and hornblende as main, and hematite, muscovite, apatite and zircon as accessary minerals. Core and rim An contents of plagioclase from porphyritic granite, medium biotite granite, K-feldspar megacryst, and mafic enclave are 36 and 21, 40 and 32, 37 and 32, and 43 and 36, respectively. $X_{Fe}$ values of hornblende are 0.57 at biotite granite, 0.51 at K-feldspar mehacryst and 0.45 at mafic enclave. $X_{Fe}$ values of biotite and hornblende are homogeneous without chemical zonation. K-feldspar megacryst shows end member of pure composition with exsolved thin lamellar pure albites. Characteristics of mineral compositions and petrography indicate porphyritic granite is igneous origin and medium-grained biotite granite comes from the same source of magma; biotite granite is initiated to solidly and from residual melt porphyritic granite can be formed. Possibly K-feldspar megacrysts are formde under H$_{2}$O undersaturation condition and near K-feldspar solidus curve temperature; growth rate is faster than nucleation rate. Mafic enclaves are thought to be mingled mafic magma in felsic magma, which is formed from compositional stratigraphy. Estimated equilibrium temperature and pressure for medium-grained biotite granite are about $800^{\circ}C$ and 4.83${\sim}$5.27 Kb, respectively.

• Journal of Soil and Groundwater Environment
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• v.13 no.5
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• pp.81-87
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• 2008

In accompany with the transfer of US army bases, recent surveys reported serious contamination of soils by the release of petroleum from storage facilities and heavy metals accumulated in rifle-ranges. These problems have made an increased concerns of cleanup technology for contaminated soils. In this study, a full-scale soil washing process improved by multistage continuous desorption and agitational desorption techniques was examined for petroleum-contaminated soils obtained from three different remedial sites that contained 29.3, 16.6, and 7.8% of silt and clay, respectively. The initial concentrations of total petroleum hydrocarbon (TPH) were 5,183, 2,560, and 4,860 mg/kg for each soil. Pure water was applied to operate washing process, in which water used for washing process was recycled 100% for over 6 months. The results of full-scale washing tests showed that the TPH concentrations for soils (> 3.0 mm) were 50${\sim}$356 mg/kg (85.2${\sim}$98.2% removal rates), regardless of the contents of silt and clay from in A, B and C soil, when the soils were washed at 3.0 kg/$cm^2$ of injection pressure with the method of wet particle separation. Based on the initial TPH concentration, the TPH removal rates for each site were 85.2, 98.2 and 89.9%. For soils in the range of 3.0${\sim}$0.075 mm, the application of first-stage desorption technique as a physical method resulted 834, 1,110, and 1,460 mg/kg of TPH concentrations for each soil, also additional multi-stage continuous desorption reduced the TPH concentration to 330, 385, and 245 mg/kg that were equivalent to 92.4, 90.6, and 90.1% removal rates, respectively. The result of multi-stage continuous desorption for fine soil (0.075${\sim}$0.053 mm) were 791, 885, and 1,560 mg/kg, and additional agitation desorption showed 428, 440, and, 358 mg/kg of TPH concentrations. Compared with initial concentration, the removal rates were 92.0, 93.9 and 92.9%, respectively. These results implied we could apply strategic process of soil washing for varies types of contaminated soils to meet the regulatory limit of TPH.

• Journal of Chest Surgery
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• v.39 no.12 s.269
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• pp.891-899
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• 2006

Background: This study is to evaluate the safety of ATS valve by examining the clinical results of ten-years experience. Material and Method: From July 1995 to March 2005, we reviewed 305 patients with ATS valve implantation. Mean age was $49.8{\pm}11.7$ years and 140(45.6%) males were included. Etiologies were rheumatic diseases in 207 cases(67.4%), degenerative changes in 57 cases(18.6%), valve dysfunction in 23 cases(7.5%) and infective endocarditis in 14 cases(4.6%). AVR was performed in 72 patients(23.5%), MVR in 156 patients (50.8%), DVR(AVR+MVR) in 63 patients(20.5%) and TVR in 16 patients(5.2%). Result: There were 9 operative mortalities(2.9%). Follow up period was $56.5{\pm}34.0(0{\sim}115)$ months and 96.4% patients were followed up with 9 late deaths. Five and ten years survival rates were $94.9{\pm}1.3%,\;91.2{\pm}2.3%$ using Kaplan-Meier's methods. Valve related event free survival rates in 5 and 10 years were $90.8{\pm}2.0%$ and $86.9{\pm}3.2%$. There were 16 anticoagulation-related hemorrhages, 6 thromboembolisms, 3 prosthetic valve endocarditis and 1 paravalvular leakage. NYHA class improved after operation(p<0.05). Postoperative echocardiography showed significant decrease in LA size, LVEDD and IVESD(p<0.01). Patients with 19 and 21 mm valve showed significantly higher transvalvular pressure gradient in aortic position(p<0.001, p<0.001). Conclusion: ATS valve showed good hemodynamic results with few valve related complications and thus can be used with acceptable risk.