• Geomechanics and Engineering
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• v.33 no.4
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• pp.401-414
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• 2023

Organic clays are ideal habitat for flora and fauna. From a geotechnical perspective, organic clays are soft, weak, variable, heterogeneous and flocculated. Portland cement is a universally common stabiliser. However, some organic acids in soil inhibit full hydration and expose cementation products to rapid dissolution. This paper investigates scopes for use of C₃S cement to enable durable cementation. Prospects of using PP fibre alongside with C₃S cement, scopes for partial replacement of C₃S cement with a plant-based nanosilica and evolution of binders are then investigated. Binding mixtures here mimic the natural functions of rhizoliths, amorphous phases, and calcites. Testing sample population include natural and fibre-reinforced clays, compact mixes of clay - C₃S cement, clay - nanobiosilica, and clay, C₃S cement and nanobiosilica. Benefits and constraints of C₃S cement and fibres for retaining the naturally flocculated structure of organic clays are discussed. Nanobiosilica provides an opportunity to cut the C₃S content, and to transition of highly compressive organic clays into an engineered, open-structured medium with >0.5 MPa compressive strength across the strains spanning from peak to 1.5-times peak.

• Journal of the Korean Ceramic Society
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• v.38 no.6
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• pp.593-595
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• 2001

Zinc-phosphate glasses에 B$_2$O$_3$를 도입하여 borate, phosphate, boro-phosphate networks가 혼재되어 있는 highly cross-linked structures를 형성시켜 Phosphate glasses의 화학적 안정화를 검토하였다. Raman 측정 결과 B$_2$O$_3$와 P$_2$O$_{5}$는 잘 혼화된 polynary networks를 이루고 있으며, 이렇게 하여 증진된 구조적 cross-linking에 의하여 xB$_2$O$_3$.(1-x)Zn$_2$P$_2$O$_{7}$ glasses의 T$_{g}$, T$_{d}$는 증가하였고 동시에 CTE는 감소하는 결과를 가져왔다.

• Journal of the Korean Ceramic Society
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• v.35 no.12
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• pp.1241-1248
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• 1998

$\beta$-C2S and C4A3 were synthesized separately and potassium oxalate was added to each system. The ad-ditive caused calcium ions in solution to decrease at early time in hydration and promoted hydration reac-tion. And then clinker which is mainly composed of $\beta$-C2S and C4A3 was synthesized at 130$0^{\circ}C$ After ad-ding potassium oxalate to it behavior of hydration was observed. It showed that the additive promoted et-tringtie formation at early time and C-S-H formation as time went on.

• Cement
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• s.130
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• pp.26-34
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• 1993

For the purpose of increasing the quality of products and reducing the grinding cost of cement clinker, some aids were studied. Some of common grinding aids, such as Ethylene Glycol, Diethylene Glycol, Triethanolamine and so on, lead to the environmental

• Journal of Life Science
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• v.29 no.12
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• pp.1364-1370
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• 2019

The anti-oxidant activity, sinigrin content, and sensory evaluation of frying batter treated with Dolsan leaf mustard powder (DLMP) were investigated. These endpoints were measured in the control sample (batter without DLMP) and seven other batters with the addition of DLMP in the following quantities: 0.03 g (S-1), 0.02 g (S-2), 0.06 g (S-3), and 0.3 g (S-4, S-5, S-6, and S-7 with different amounts of red pepper powder). The acid value (AV) and peroxide value (POV) were low in the S-4 and S-5 batters; the total polyphenol content was 190.97 mg GAE/g in the control sample and 721.17 mg GAE/g in S-4; and the total flavonoid content of S-6 was 67.82 mg QE/g which was higher than that of the control sample. The anti-oxidant activity was measured by EDA, ABTS, and FRAP assays and was seen to rise as the amount of DLMP increased. Moreover, sinigrin content was higher in S-4, S-5, S-6, and S-7 than in the control, S-1, S-2, and S-3, and there were no significant differences among S-4 to S-7 when just 0.3 g of DLMP was added. Sensory evaluation showed that color, flavor, taste, texture, and overall acceptability values were significantly higher in S-4 and S-5, and that there was no significant difference across the samples. The addition of DLMP is therefore expected to increase the anti-oxidant activity of frying batter which would be effective in improving the storage and quality of the product.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11b
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• pp.245-247
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• 2003

축산폐수에서 분리된 세균 S. sp1(S. capitis)와 S. sp2(3. xylosus)를 이용한 축산폐수 중 질소화합물 분해정도를 파악한 결과 1) 증식에 알맞은 조건은 LB broth, $27^{\circ}C$, pH7로 나타났다. 2) S. sp1은 배양 7일 초기 농도의 90.3%, 7일째 32.9%로 감소되어 14일까지 다소 증가하면서 유지되었다. 3) S. sp1과 S. sp2를 혼합배양한 결과 S. sp1과 S. sp2 단독배양보다 분해 효율이 높고 기간도 2일정도 단축되었다.

• The Journal of Natural Sciences
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• v.11 no.1
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• pp.33-39
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• 1999

Electrochemical behaviors of $Sm^3+$-ARS complexes has been investigated by d.c.polarography, differential pulse polarography and cyclic voltammetry. $Sm^3+$forms 1 : 3 adsorptive complexes with ARS.The reduction potential of complex wave $(P_2)$ shifted more negatively than the ligand wave $(P_1)$. The linear calibration curves of decreasing $P_1$ and increasing $P_2$ is obtained when $Sm^3+$ concentration varies from TEX>$2{\times}10^{-6}$ M to $3.2{\times}10^{-5}$ M.

• Economic and Environmental Geology
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• v.39 no.6 s.181
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• pp.643-651
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• 2006

The Pb-Ag-Bi-S system minerals such as galena-matildite solid solutions, cosalite and heyrovskyite occur in the Nakdong As-Bi deposits. Galena-matildite solid solutions commonly coexisting with native bismuth fill in microfractures of pyrite grains and form irregular shapes. Cosalite forms composite grains including native bismuth, heyrovskyite and Bi-Te-S system minerals in the matrix of quartz vein. Matildite from the Nakdong deposits has an end member composition, $Ag_{1.07-1.11}Bi_{1.12-1.20}S_2$, and an excess concentration of $0.3{\sim}2.4$ mole % $Bi_2S_3$ compared to the stoichiomeoic value. PbS concentrations in $PbS-AgBiS_2$ solid solutions do not exceed 54 mole %. The average chemical composition of cosalite in the study area is $Pb_{1.79}Bi_{2.29}Ag_{0.12}S_5$. Pb is slightly depleted compared to the ideal composition, but the concentrations of Ag and Cu reach as much as 1.47 wt.% and 0.27 wt.%, respectively. Heyrovskyite has the chemical formula of $Pb_{5.01}Ag_{0.26}Bi_{2.70}S_9$ suggesting that there occurs the coupled substitution of $2Bi^{3+}$ for $3Pb^{2+}$ as well as that of $Ag^++Bi^{3+}$ for $2Pb^{2+}$. The genetic condition of Pb-Ag-Bi-S system minerals can be confined to the temperature of $220{\sim}270^{\circ}C$ and the pressure below 200 bars.

• Journal of fish pathology
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• v.17 no.2
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• pp.91-98
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• 2004

This study was performed for the identification of Streptococcus sp. from cultured flounders (Paralichthys olivaceus) showing streptococcosis in the Jeju island. We isolated 10 strains of Streptococcus iniae from the cultured olive flounders with streptococcosis. Isolated strains were identified in S. iniae since they have formed the expected band through performing PCR assay using specific primers, Sin-1 (5'-CTAGAGTACACATGTACT(AGCT)AAG-3') and Sin-2 (5'-GGATTTTCCACTCCCATTAC-3'). In addition to 16S-23S rRNA intergenic spacers (ISR), operon structure of isolated strains showed that all strains had three 16S-23S rRNA ISR band patterns. The 16S-23S rRNA ISR sequence of isolated strains showed 96% sequence identity with S. iniae (GenBank accession number AF 048773). This paper is the first report that S. iniae is associated with streptococcosis of Olive flounder in Korea.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.115-118
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• 2012

Purpose: The Levey-Jennings chart controlled measurement values that deviated from the tolerance value (mean ${\pm}2SD$ or ${\pm}3SD$). On the other hand, the upgraded Westgard Multi-Rules are actively recommended as a more efficient, specialized form of hospital certification in relation to Internal Quality Control. To apply Westgard Multi-Rules in quality control, credible quality control substance and target value are required. However, as physical examinations commonly use quality control substances provided within the test kit, there are many difficulties presented in the calculation of target value in relation to frequent changes in concentration value and insufficient credibility of quality control substance. This study attempts to improve the professionalism and credibility of quality control by applying Westgard Multi-Rules and calculating credible target value by using a commercialized quality control substance. Materials and Methods : This study used Immunoassay Plus Control Level 1, 2, 3 of Company B as the quality control substance of Total T3, which is the thyroid test implemented at the relevant hospital. Target value was established as the mean value of 295 cases collected for 1 month, excluding values that deviated from ${\pm}2SD$. The hospital quality control calculation program was used to enter target value. 12s, 22s, 13s, 2 of 32s, R4s, 41s, $10\bar{x}$, 7T of Westgard Multi-Rules were applied in the Total T3 experiment, which was conducted 194 times for 20 days in August. Based on the applied rules, this study classified data into random error and systemic error for analysis. Results: Quality control substances 1, 2, and 3 were each established as 84.2 ng/$dl$, 156.7 ng/$dl$, 242.4 ng/$dl$ for target values of Total T3, with the standard deviation established as 11.22 ng/$dl$, 14.52 ng/$dl$, 14.52 ng/$dl$ respectively. According to error type analysis achieved after applying Westgard Multi-Rules based on established target values, the following results were obtained for Random error, 12s was analyzed 48 times, 13s was analyzed 13 times, R4s was analyzed 6 times, for Systemic error, 22s was analyzed 10 times, 41s was analyzed 11 times, 2 of 32s was analyzed 17 times, $10\bar{x}$ was analyzed 10 times, and 7T was not applied. For uncontrollable Random error types, the entire experimental process was rechecked and greater emphasis was placed on re-testing. For controllable Systemic error types, this study searched the cause of error, recorded the relevant cause in the action form and reported the information to the Internal Quality Control committee if necessary. Conclusions : This study applied Westgard Multi-Rules by using commercialized substance as quality control substance and establishing target values. In result, precise analysis of Random error and Systemic error was achieved through the analysis of 12s, 22s, 13s, 2 of 32s, R4s, 41s, $10\bar{x}$, 7T rules. Furthermore, ideal quality control was achieved through analysis conducted on all data presented within the range of ${\pm}3SD$. In this regard, it can be said that the quality control method formed based on the systematic application of Westgard Multi-Rules is more effective than the Levey-Jennings chart and can maximize error detection.