• Resources Recycling
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• v.13 no.1
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• pp.47-53
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• 2004

As a basic study of the re-using molten converter slag as an ordinary portland cement by conversion process, molten slag and sintered CaO pellet was reacted each other. The dissolution rate of the sintered CaO pellet into the molten slag was measured and the changes of the reaction layer was also investigated. The converter slag reagent-grade $SiO_2$ added was melted and hold for 30 minutes in MgO crucible between $1350∼1500 ^{\circ}C$. Then sintered CaO pellet heated at the same temperature was dipped into the molten slag and hold for 10∼30 min. After the reaction, the crucible was cooled in air and the specimen was cut off to the horizontal direction of the crucible. The dissolution rate of CaO pellet was measured by the change of the radius of sintered CaO pellet and the interface layer was observed by SEM/EDX and XRD. The dissolution rate of sintered CaO pellet contacted with the slag of basicity 1 was 9.8 $\mu\textrm{m}$/min at $1350^{\circ}C$ and increased to 18.0 $\mu\textrm{m}$/min at $1500^{\circ}C$. The rate was slightly decreased to 7.6 $\mu\textrm{m}$/min at $1350^{\circ}C$ and 15.0 $\mu\textrm{m}$/min at $V^{\circ}C$ in the slag of basicity 2. The dissolution rate of CaO in converter slag was followed to the rule of Arrhenius' temperature dependency, and the apparent activation energy of the dissolution of CaO was 36 kcal/mole. In case of the slag basicity of 1, the thickness of $C_2$S layer was 64-118 $\mu\textrm{m}$ and the thickness of $C_3$S was 28∼90 $\mu\textrm{m}$ for 10∼30 minutes at $1500^{\circ}C$. And the thickness of the $C_3$S layer was 90∼120 $\mu\textrm{m}$ at the same conditions in the slag basicity of 2.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.6
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• pp.647-653
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• 2007

The ultimate objective of this study is to develop a reliable oxygen-enriched combustion techniques especially for the case of the flue gas recycling in order to reduce the $CO_2$ emissions from practical industrial boilers. To this end a systematic numerical investigation has been performed, as a first step, for the resolution of the combusting flame characteristics of lab-scale LNG combustor. One of the important parameters considered in this study is the level of flue gas recycling calculated in oxygen enriched environment. As a summary of flame characteristics, for the condition of 100% pure $O_2$ as oxidizer without any flue gas recycling, the flame appears as long and thin laminar-like shape with relatively high flame temperature. The feature of high peak of flame temperature is explained by the absence of dilution and heat loss effects due to the presence of $N_2$ inert gas. The same reasoning is also applicable to the laminarized thin flame one, which is attributed to the decrease of the turbulent mixing. These results are physically acceptable and consistent and further generally in good agreement with experimental results appeared in open literature. As the level of $CO_2$ recycling increases in the mixture of $O_2/CO_2$, the peak flame temperature moves near the burner region due to the enhanced turbulent mixing by the increased amount of flow rate of oxidizer stream. However, as might be expected, the flue gas temperature decreases due to presence of $CO_2$ gas together with the inherent feature of large specific heat of this gas. If the recycling ratio more than 80%, gas temperatures drop so significantly that a steady combustion flame can no longer sustain within the furnace. However, combustion in the condition of 30% $O_2/70% $ $CO_2$ can produce similar gas temperature profiles to those of conventional combustion in air oxidizer. An indepth analyses have been made for the change of flame characteristics in the aspect of turbulent intensity and heat balance.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.12
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• pp.1287-1293
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• 2008

In this study, a blend of 2-amino-2-methyl-1-propanol (AMP) and ammonia (NH$_3$) was used to achieve high absorption rates for carbon dioxide (CO$_2$) as suggested at several literatures. The absorption rates of aqueous AMP and blended AMP+NH$_3$ solutions with CO$_2$ and nitrogen dioxide (NO$_2$) were measured using a stirred-cell reactor at 303 K. The effect of the added NH$_3$ to enhance absorption characteristics of AMP was studied. The performances were evaluated under various operating conditions. The absorption rates increased following the increase of the concentration of NH$_3$. The absorption rate of NH$_3$ blended into 30 wt.% AMP solution with NO$_2$ at 303 K was 12.6$\sim$32.6% higher than that of aqueous AMP solution without NH3. Also, the addition of 3 wt.% NH$_3$ to 30 wt.% AMP increased 48.2$\sim$41.6% values for the reactions with CO$_2$ and NO$_2$ at 303 K. Therefore, it clearly shows that the reaction rate of AMP with CO$_2$ and NO$_2$ can be increased by the addition of NH$_3$.

• Childhood Kidney Diseases
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• v.8 no.1
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• pp.33-42
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• 2004

Purpose : Children with nephrotic syndrome(NS) are under high risk for metabolic bone disease(MBD) as a complication of long-term glucocorticoid therapy. We prospectively evaluated the effect of oral bisphosphonate(alendronate) therapy in children with NS, which has proven efficacy in adult patients with glucocorticoid induced MBD. Methods : Among 58 children with NS, aged 5 to 8 years and haying a disease duration of more than 2 years, 30(51.7%) were enrolled to meet the selection criteria, less than -1.0 Z-scores of lumbar spine bone mineral density(BMD) by dual energy X-ray absorptiometry (DEXA). These 30 children were divided into three groups and each were assigned to receive alendronate, calcitriol, and no-medication, respectively for one year. Lumbar spine BMD was followed up every 6 months and the biochemical indexes were measured before and 1 year after the treatment. There were no significant difference among groups with respect to the average age, the initial BMD, and the cumulative steroid doses. Analysis of the treatment efficacy was done by the % change of BMD and by the changes in Z-scores of lumbar spine BMD. Results : Mean age and disease duration of patients at the initial lumbar spine BMD evaluation was $7.4{\pm}1.7$ years and $2.2{\pm}1.2$ years, respectively. Twenty-three of 30 children(76%) had osteopenia, and seven(23%) had osteoporosis. There was no difference in the biochemical values among the groups, before and 1 year after the treatment(P<0.05). Twenty two children(73.3%) with frequent relapsing or steroid dependant NS had more frequent MBD, compared to the 8 children(26.6%) with infrequent relapsing NS. The one year % changes of BMD were 8.56 in alendronate group, 5.79 in calcitriol group, and 1.9 in no-medication group. The changes in Z-score of lumbar spine BMD increased in the alendronate group and the calcitriol group, but not in the no-medication group. One year % changes of BMD were different among groups(P=0.0002). Significant differences were found between the alendronate and the no-medication group, and between the calcitriol and the no-medication group(P<0.05). There was no difference between the alendronate and the calcitriol group. No serious adverse effect was observed in the alendronate group. Conclusion : Children with NS receiving high dose steroids are under the high risk of BMD and should undergo regular BMD evaluation. Z-score of lumbar spine BMD was a useful parameter in diagnosing low bone mass in children. Alendronate weekly oral therapy was effective and relatively safe in increasing the lumbar spine BMD in children with NS having steroid induced MBD.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.285-296
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• 1995

Anatomical studies of sink tissues are required for better understanding the biological plant growth system and energy metabolism. Kinematics of root growth zones of two genotypes of tall fescue (Festuca arundinacea Schreb.) receiving 50 or 200 ppm N were determined. Longitudinal anatomy and cell dynamics of root growth zones were studied and calculated. The root growth zone is organized similarly to the leaf growth zone which has cell division, elongation, and maturation zones, but the root growth zone is only about 3.0 mm long compared to 25 to 30 mm for the leaf growth zone. The root cap extends about 0.4 to 0.5 mm from the apical initial, while the cell elongation zone for both cortical and metaxylem cells extends about 3.3 mm from the apical initial for both genotypes and N levels. Root cap cells elongate from an initial length of about 5$\mu{m}$ long to a final length of about 40$\mu{m}$ before being sloughed. Initial lengths of cortical and metaxylem cells were about 8.5 $\mu{m}$ and 13.0 $\mu{m}$, respectively. Elongation of cortex and metaxylem cell showed sigmoidal curves with final lengths of about 120 $\mu{m}$ for cortex cells and 650 $\mu{m}$ for metaxylem cells. Initial size and final size for both types were not affected by N level, but cell fluxes and cell elongation rates of cortical and metaxylem cells were about double in low N. Cell production rates were about 5 to 6 times higher in cortical cells than in metaxylem cells. Differences in N caused a larger change in cell production rate, duration of cell elongation, and relative cell elongation rate than did the genotypes. These data indicate that N application affects root growth longitudinally by changing cell production rate and elongation rate.

• Economic and Environmental Geology
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• v.51 no.4
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• pp.345-358
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• 2018

In this study, we have performed electron probe micro analyzer (EPMA), X-ray differaction (XRD), inductively coupled plasma spectroscopy (ICP), Fourier transform Raman spectroscopy (FT-Raman), far-infrared (FIR), nuclear magnetic resonance (NMR), and pH-DO Analyses for characterizing medicinal mineralogy aspect of the black tourmaline (Shantung, china), black and pink tourmaline (Minas Geraris, Brazil), black touemaline (Daeyu mine, Korea). In addition, heating effects of the tourmaline sauna as well as the effects of tourmaline powder-added soap on skin troubles have been investigated. It has been revealed that chemical composition of the tourmaline is either high in Fe-, Al-, B-rich types. Ratio of the K-Ca, Na-K, and Fe-B reflects the component change property of solid solution. $CaO/CaO+Na_2O$ and MgO/FeO+MgO ratio show high positive correlation. When tourmaline reacts with distilled water, extended reaction time DO values approximately decrease and it stabilizes at DO = 10. Otherwise, pH values increase until 6 hours and it stabilizes at pH = 8 after 24 hours. Distilled water changes to alkaline when it reacts with tourmaline powder and particles. Tourmaline showed lower absorption spectrum strength and transmittance at short wave, where absorption spectrum wavelength and strength were determined by the content of the composition elements and characteristics of crystallography. Increase of the Fe content has been confirmed to be the cause for the reduction of irradiation. For the chemical composition and spectral property of the tourmaline particle samples, it has been found that Si and Fe contents show positive correlation with Far-Infrared irradiation, while Al and Mg contents show negative correlation. For tourmaline powder, it has been confirmed that $^{17}O-NMR$ FWHM (full width at half maximum) decreases when reacts with distilled water. Tourmaline sauna (approximately $100^{\circ}C$) was found to increase $0.5-1.5^{\circ}C$ of body temperature, average of 12 heartbeat, and 10mg Hg of blood pressure. Tourmaline soap had very good aesthetic effect to skin and was confirmed to have above the average improvements to skin troubles (e.g., allergy or atopy).

• Economic and Environmental Geology
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• v.51 no.4
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• pp.359-370
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• 2018

The batch and column experiments were performed to overcome the limitation of the neutralization process using the $scCO_2$-water-recycled aggregate, reducing its treatment time to 3 hour. The waste cement mortar and two kinds of recycled aggregate were used for the experiment. In the extraction batch experiment, three different types of waste mortar were reacted with water and $scCO_2$ for 1 ~ 24 hour and the pH of extracted solution from the treated waste mortar was measured to determine the minimum reaction time maintaining below 9.8 of pH. The continuous column experiment was also performed to identify the pH reduction effect of the neutralization process for the massive recycled aggregate, considering the non-equilibrium reaction in the field. Thirty five gram of waste mortar was mixed with 70 mL of distilled water in a high pressurized stainless steel cell at 100 bar and $50^{\circ}C$ for 1 ~ 24 hour as the neutralization process. The dried waste mortar was mixed with water at 150 rpm for 10 min. and the pH of water was measured for 15 days. The XRD and TG/DTA analyses for the waste mortar before and after the reaction were performed to identify the mineralogical change during the neutralization process. The acryl column (16 cm in diameter, 1 m in length) was packed with 3 hour treated (or untreated) recycled aggregate and 220 liter of distilled water was flushed down into the column. The pH and $Ca^{2+}$ concentration of the effluent from the column were measured at the certain time interval. The pH of extracted water from 3 hour treated waste mortar (10 ~ 13 mm in diameter) maintained below 9.8 (the legal limit). From XRD and TG/DTA analyses, the amount of portlandite in the waste mortar decreased after the neutralization process but the calcite was created as the secondary mineral. From the column experiment, the pH of the effluent from the column packed with 3 hour treated recycled aggregate kept below 9.8 regardless of their sizes, identifying that the recycled aggregate with 3 hour $scCO_2$ treatment can be reused in real construction sites.

• Journal of Korean Medical classics
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• v.13 no.1
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• pp.269-303
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• 2000

The xin(心) has various meanings in ${\ll}$Huangdineijing(黃帝內經)${\gg}$ but they sometimes contradict each other. This thesis divided the xin into the meaning and the Zang-xiang(藏象), and then analyzed the xin's notion in detail. The concept of the xin in ${\ll}$Huangdineijing(黃帝內經)${\gg}$ is sorted out into : the notion of space, yin-yang five elements(陰陽五行) and shen(神) The xin is the upper part of body and it possesses the character of yang(陽). So the concept of the breast has originated from this character and it rightly belonged to the top. The xin is assigned to fire among five elements, 'chang(長)', which has the energy of moving forward, noon at a day when yang-qi(陽氣) is properous and shows 'gu(鉤)' & 'keo(矩)' in pulse condition. The xin possesses the character, 'Taiyang of the yang(陽中之太陽)' along with the notion of space combined with five elements. That is, the notion of upper space means 'of the yang(陽中)', and, fire in five elements means 'yang'. This is similar to '=(Taiyang)' of Sasang(四象) at ${\ll}$the Book of Changes(周易)${\gg}$ Since the xin puts shen(神) in order, actions of spirit have effect on the xin. And it depends whether the sense of vitality is broad or narrow. The xin related with broad sense of spirit is 'monarch of the organs(君主之官)'. Therefore it has control over the human body. As it also directly effects the life or death, Pericardium(心句) substitutes the xin and protects the external invasion. In Shi-er-won(十二原) and Bonsu(本輸), instead of the Xin Channel the Pericardium Channel was used in healing patients. The xin can be interpretable as the mind, because the xin includes spirit. The mind can be distinguished into 'desire' and 'state of profound reason'. In ${\ll}$Huangdineijing(黃帝內徑)${\gg}$, the disease of the xin caused by emotion was mentioned many times. This emotion is 'desire' which resorted to the sentiment. The reason one mind has both character is; man preserves given principle (reason) and emotion reveals via the reason exercised. The above is about the xin related with the broad sense of vitality. Concerning the narrow sense of vitality, one of the five vitalities is stored with the others away in the five solid organs. Then it takes part in the operation of five body constituents and it is linked with the personified description of five solid organs. The xin, spleen, stomach and kidney are 'the ground of life'. Spleen and stomach are the origin of making qi and blood, which 'means the ground after birth'. Kidney keeps the essence of life, and manages the growing and generative function of human body. The xin keeps 'Shin-myung(神明)', in other words, it has control over and supervise whole activity of body. Therefore xin's role is needed for the appropriate working of spleen, stomach and kidney. And 'Shin-myung' is its motive power. In ${\ll}$Huangdineijing(黃帝內經)${\gg}$, the reason why xin was assigned to September and October is that yang-qi of the human body goes to the inner part, with xin at the same time. This explains that yang-qi of the human body is adapted to change of season and goes into xin-fire(心火) in order to get away from the cold. In this case, heart means more inner part than liver, spleen and lung. Mengzi(孟子), philosopher of the China's turbulent ages emphasized the thinking function of xin. Sunzi(荀子) asserted that xin is 'heaven monarch(天君)' and the other organs are 'heaven rninisters(天官)'. This conception is similar to 'monarch of the organs' of ${\ll}$Huangdineijing(黃帝內經)${\gg}$. After the Ming Dynasty, commentators of Huangdineijing(黃帝內經) explained the heart, as 'monarch of the organs', or 'the master of body(一身之主)'. This was due to the influence of Sung Confucianism.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.4
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• pp.41-50
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• 2017

The design of proper agitation system is requisite in biological waste treatment and energy generation plant, which is affected by viscosity, impeller types, and power consumption. In the present work, hydrogen fermentation of food waste was conducted at various operational pHs (4.5~6.5) and substrate concentrations (10~50 g Carbo. COD/L), and the viscosity of fermented broth was analyzed. The $H_2$ yield significantly varied from 0.51 to $1.77mol\;H_2/mol\;hexose_{added}$ depending on the pH value, where the highest performance was achieved at pH 5.5. The viscosity gradually dropped with shear rate increase, indicating a shear thinning property. With the disintegration of carbohydrate, the viscosity dropped after fermentation, but it did not change depending on the operational pH. At the same pH level, the $H_2$ yield was not affected much, ranging $1.40{\sim}1.86mol\;H_2/mol\;hexose_{added}$ at 10~50 g Carbo. COD/L. The zero viscosity and infinite viscosity of fermented broth increased with substrate concentrations, from 10.4 to $346.2mPa{\cdot}s$, and from 1.7 to $5.3mPa{\cdot}s$, respectively. There was little difference in the viscosity value of fermented broth at 10 and 20 g Carbo. COD/L. As a result of designing the agitation intensity based on the experimental results, it is expected that the agitation intensity can be reduced during hydrogen fermentation. The initial and final agitation intensity of 30 g Carbo. COD/L in hydrogen fermentation were 26.0 and 10.0 rpm, respectively. As fermentation went on, the viscosity gradually decreased, indicating that the power consumption for agitation of food waste can be reduced.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.2
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• pp.39-44
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• 2020

Recently, numerous researches are being conducted in flexible substrate to apply to wearable devices. Particularly, Conductive substrate researches that can implement the wearable devices on clothing are massive. In this study, we formed fiber substrate spraying CNT and Pd mixed solution on it and plated metal layer with electroless plating. Used SEM equipment and EDS analysis to analysis structure of the plated fiber substrate and discovered Ni layer was created. For check electrical properties, mapping was performed to check surface resistance and distribution of resistance of electroless plated fiber substrate with 4-point probe. It was confirmed that conductivity was improved as the duration of electroless plating was increased, and it was found that distribution of resistance by surface location was uniform. Changes in resistance due to mechanical stress were measured through tensile, bending, and twisting tests. As a result, it was confirmed that resistance change of flexible substrate gradually disappeared as plating time increased. Using UTM (Universal testing machine), it was analyzed mechanical properties of the electroless plated substrate with respect to changes in plating time were improved. In the case of conductive fiber substrate in which electroless plating was performed for 2 hours, tensile strength was increased by 16 MPa than fiber substrate. Based on these results, we found that Ni-CNT-Fabric flexible substrate is adequate for clothing-intergrated conductive substrate and we positively expect that this experiment shows flexible substrate can adapt to and develop not only a wearable device technology but also other fields needing flexibility such as battery, catalyst and solar cell.