• Ocean Science Journal
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• v.43 no.4
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• pp.195-208
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• 2008

This paper evaluates whether a thermodynamic ocean-carbon model can be used to predict the monthly mean global fields of the surface-water partial pressure of $CO_2$ ($pCO_{2SEA}$) from sea surface salinity (SSS), temperature (SST), and/or nitrate ($NO_3$) concentration using previously published regional total inorganic carbon ($C_T$) and total alkalinity ($A_T$) algorithms. The obtained $pCO_{2SEA}$ values and their amplitudes of seasonal variability are in good agreement with multi-year observations undertaken at the sites of the Bermuda Atlantic Timeseries Study (BATS) ($31^{\circ}50'N$, $60^{\circ}10'W$) and the Hawaiian Ocean Time-series (HOT) ($22^{\circ}45'N$, $158^{\circ}00'W$). By contrast, the empirical models predicted $C_T$ less accurately at the Kyodo western North Pacific Ocean Time-series (KNOT) site ($44^{\circ}N$, $155^{\circ}E$) than at the BATS and HOT sites, resulting in greater uncertainties in $pCO_{2SEA}$ predictions. Our analysis indicates that the previously published empirical $C_T$ and $A_T$ models provide reasonable predictions of seasonal variations in surface-water $pCO_{2SEA}$ within the (sub) tropical oceans based on changes in SSS and SST; however, in high-latitude oceans where ocean biology affects $C_T$ to a significant degree, improved $C_T$ algorithms are required to capture the full biological effect on $C_T$ with greater accuracy and in turn improve the accuracy of predictions of $pCO_{2SEA}$.

• Restorative Dentistry and Endodontics
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• v.45 no.4
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• pp.42.1-42.9
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• 2020

Objective: This study aimed to examine the physical properties (pH and flow) of 2 novel bioceramic sealers. Materials and Methods: The tested sealers were a calcium hydroxide sealer (Sealapex) and 2 bioceramic sealers (BioRoot RCS and TotalFill BC Sealer). Flow measurements were conducted according to ISO 6876/2012, with a press method of 0.05 mL of sealer. The pH of fresh samples was tested immediately after manipulation, while set samples were stored for 3 times the recommended setting time. The predetermined time intervals ranged from 3 minutes to 24 hours for fresh samples and from 10 minutes to 7 days and 4 weeks for the set samples. Analysis of variance was performed, with p = 0.05 considered indicating significance. Results: The mean flow values were 26.99 mm for BioRoot, 28.19 for Sealapex, and 30.8 mm for TotalFill BC Sealer, satisfying the ISO standard. In the set samples, BioRoot RCS had higher pH values at 24 hours to 1 week after immersion in distilled water. At 2 weeks, both bioceramic sealers had similar pH values, greater than that of Sealapex. In the fresh samples, the bioceramic sealers had significantly higher initial pH values than Sealapex (p < 0.05). At 24 hours post-immersion, all sealers showed an alkaline pH, with the highest pH observed for TotalFill. Conclusions: The TotalFill BC Sealer demonstrated the highest flow. The bioceramic sealers initially presented higher alkaline activity than the polymeric calcium hydroxide sealer. However, at 3 and 4 weeks post-immersion, all sealers had similar pH values.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.180-185
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• 1999

Rotating Biological Contactor (RBC) was tested for the treatment of artificial rearing water in n simulated aquaculture system. Performance of RBC on the removal of TAN and COD was evaluated by controlling hydraulic residence time (HRT). As HRT of RBC was increased, TAN removal rate ana removal efficiency of RBC and TAN concentration of rearing water were increased, but COD removal rate was decreased. Total alkalinity consumption rate was increased by increasing HRT of RBC. Ratio between total alkalinity consumption rate and TAN removal rate was 7.73. HRT for maintaining lowest TAN and COD concentration of artificial rearing water was 14,6 minutes and at that condition TAN and COD concentration of the water was 1.28 and $5.59 g/m^3$, respectively.

• Journal of Aquaculture
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• v.15 no.1
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• pp.49-60
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• 2002

Research on practices for improving water quality in channel catfish Ictalurus punctatus ponds was conducted at the Auburn University Fisheries Research Station, Auburn, Alabama, in 1998 and 1999. The objective of this two-year study was to determine better management practices to enhance water quality and improve production efficiency. In the first year, oxidation of bottom soil by drying, tilling, and applying sodium nitrate was performed (dry-till and dry-till with sodium nitrate treatments). The second year, based on the results obtained during the first year, precipitation of phosphorus (P) from water by applying gypsum was compared to the dry-till treatment (dry-till and dry-till with gypsum treatments). Control ponds were not subjected to bottom drying, tilling, sodium nitrate, or gypsum treatment. Channel catfish fingerings were stocked at 15,000/ha. In the first year, water in ponds from dry-till and dry-till with sodium nitrate treatments had lower concentrations (P < 0.01) of soluble reactive P, nitrate ($NO_{3} ^{-}) and nitrite ($NO_{2} ^{-}) nitrogen (N), total ammonia ($NH_3$) nitrogen, total suspended solids and turbidity, and higher values of pH, Secchi disk visibility, total alkalinity, total hardness, and calcium ($Ca^{2+}) hardness than water in control ponds. Ponds of the dry-till treatment also had lower concentrations (P < 0.01) of total P and total N than control ponds. Total fish production and survival rate did not differ among the treatments (P > 0.05). The findings suggested that drying and tiling pond bosoms between crops could achieve water quality improvement. Applying sodium nitrate to dry, tilled pond bosoms did not provide water quality improvement. In the second year, the treatment with the best results from the first year, dry-till, was compared with a dry-till with gypsum treatment. Enough gypsum was applied to give a total hardness of about 200 mg/L, and gypsum was reapplied as needed to maintain the hardness. Compared to the control, dry-till and dry-till with gypsum treatments had lower concentrations (P < 0.01) of total and soluble reactive P, total N, and total $NH_3$-N, and higher concentrations (P < 0.01) of dissolved oxygen. Ponds of the duty-till with gypsum treatment also had lower concentrations (P < 0.01) of chlorophyll $\alpha$, chemical oxygen demand, and total alkalinity than the control. Total fish production and survival rate did not differ (P > 0.05) among the treatments. These findings suggest that drying and tilling pond bosoms between crops and treating low hardness waters with gypsum could achieve water Quality improvement.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.217-222
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• 2004

This study was conducted to estimate if the level of several chemical ingredients including alkanolamines or ethanolamines (EA) examined in the specific synthetic metalworking fluid (MWF) ‘A’ can cause anti-microbial activity and health effect. Three water-based MWF products (‘A’, ‘B’, and ‘C’) were studied every week for two months. Chemical ingredients such as formaldehyde, boron, EA, and copper were examined. In the sump where MWF ‘A’ was used, not only the total level of EA, monoethanolamine(MEA), diethanolamine(DEA) and triethanolamine(TEA), but also boron level were significantly higher than those of the other MWFs. ANOVA statistical tests indicated that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF ‘A’ were significantly higher than those in other MWF types. Correlation tests also found that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF ‘A’ are significantly correlated. We suggested the assumptions that excessive concentrations of EA, and borate at a high pH level, may cause anti-microbial resistance synergically. To demonstrate this assumption, additional study is needed to examine the relationship between the levels of microbes and excessive concentrations of EA, and borate at a high pH level.

• Journal of environmental and Sanitary engineering
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• v.24 no.4
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• pp.80-89
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• 2009

In the organic waste, food waste is the most difficult controls. In the study, food waste was treatmented to removal only the dockage. To decrease the hydrogen sulfide($H_2S$) in the produced biogas, iron chloride put in the anaerobic digester. Respectively treatment quantity of the food waste, content of the methane($CH_4S$) gas in the biogas, produced gases quantity, put in the quantity of the Iron chloride, pH, TS, Alkalinity, VFA, Ammonia. The results obtained from the experiment are as follows: 1. The produced biogases quantity/the treatment quantity of the food waste was $83.82{\sim}129.41m^3/ton$. 2. The content of the hydrogen sulfide($H_2S$) in the produced biogas is below of the 500ppm. The iron chloride put in the anaerobic digester. 200~300kg of the iron chloride put in the anaerobic digester at the steady-state. 400~850kg of the iron chloride put in the anaerobic digester at the unsteady-state. 3. Factor of the operator was the pH: 7.7~8.4, content of mathane: 55~65%. 4. TS(total solid) of the digestor sludge was 17~20%, Alkalinity was 38,500~41,750ppm, VFA(Volatile Fatty Acids) was 2,800~2,420ppm, Ammonia was 4,300~3,650ppm.

• KSTLE International Journal
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• v.4 no.2
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• pp.52-55
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• 2003

This study was conducted to estimate if the level of several chemical ingredients including alkanolamines or ethanolamines (EA) examined in the specific synthetic metalworking fluid (MWF) "A" can cause anti-microbial activity and health effect. Three water-based MWF products ("A", "B", and "C") were studied every week for two months (from June 1, 2002 to July 30, 2002). Chemical ingredients such as formaldehyde, boron, EA, and copper were examined. In the sump where MWF "A" was used, not only the total level of EA, monoethanolamine(MEA), diethanolamine(DEA) and triethanolamine(TEA), but also boron level were significantly higher than those of the other MWFs. ANOVA statistical tests indicated that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF "A" were significantly higher than those in other MWF types. Correlation tests also found that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF "A" are significantly correlated. We suggested the assumptions that excessive concentrations of EA, and borate at a high pH level, may cause anti-microbial resistance synergically. To demonstrate this assumption, additional study is needed to examine the relationship between the levels of microbes and excessive concentrations of EA, and borate at a high pH level.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.213-216
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• 2003

This study was conducted to estimate if the level of several chemical ingredients including alkanolamines or ethanolamines (EA) examined in the specific synthetic metalworking fluid (MWF) “A” can cause anti-microbial activity and health effect. Three water-based MWF products (“A”, “B”, and “C”) were studied every week for two months (from June 1, 2002 to July 30, 2002). Chemical ingredients such as formaldehyde, boron, EA, and copper were examined. In the sump where MWF “A” was used, not only the total level of EA, monoethanolamine(MEA), diethanolamine(DEA) and triethanolamine(TEA), but also boron level were significantly higher than those of the other MWFs. ANOVA statistical tests indicated that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF A were significantly higher than those in other MWF types. Correlation tests also found that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF “A” are significantly correlated. We suggested the assumptions that excessive concentrations of EA, and borate at a high pH level, may cause anti-microbial resistance synergically, To demonstrate this assumption, additional study is needed to examine the relationship between the levels of microbes and excessive concentrations of EA, and borate at a high pH level.

• Korean Journal of Food Science and Technology
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• v.9 no.1
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• pp.10-12
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• 1977

Chemical constituents and amino acid contents of tea leaves which were harvested three times (May, July and August) from the tree at two different locations were studied. The contents of total nitrogen, ascorbic acid and amino acid decreased, while those of fiber and tannin increased in the order of May, July and August crops. No differences were observed in the contents of reducing sugar, caffeine and ash among tea leaves harvested at different times. There were no effects of locations on the contents of chemical constituents of tea leaves.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.98-103
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• 2001

In order to understand the characteristics of leachate at the Seokdae municipal waste landfill in the Pusan city, the correlation between leachate pollution loading and volume of gas production. concentration of gas and subsidence of ground, the characteristical methos, geochemical analyses and laboratory column tests using samples of gases, leachate and surface soil of Seokdae waste landfill area. Through the analysis of water balance, leachate flow rate and pollution loading were estimated. Geistatistical analysis of four gas components ( $O_2$, C $H_4$, $H_2$S and CO) shows the possibility of ground subsidence around the group of a site with high concentration of gas. From geochemical analyses of leachate, EC and Total-Alkalinity of ground subsidence around the group of a site with high concentration of gas. From geochemical analysis of leachate, Ec and Total-Alkalinity were increased, and Cl, Cr, Mn, Cu, Zn, Cd and Pb were decreassed comparing to the part, and the type of water quality was Na-HC $O_3$ in trilinear diagram. It shows that biodecomposition of municipal wastes continues actively. From the analysis of water balance, the total leachate flow rate is about 465.11㎥/day and pure pollution loading of Cl, Mn and Fe are estimated to 223.8kg/day, 0.2kg/day, 0.3kg/day, respectively. The laboratory column test of residual soil and landfill soil shows 0.206cm and 0.019cm for linear velocity(equation omitted), 0.234 $\textrm{cm}^2$/min and 0.018$\textrm{cm}^2$/min for diffusion coefficient ( $D_{ι}$), and 1.136cm and 0.095cm longitudinal dispersion index ($\alpha$$_{ι}$), respective]y. It demonstrates that the delay time of contamination for residual soil is shorter than that of landfill soil.