• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.20 no.1
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• pp.49-55
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• 2024

Stainless 630 (or 17-4PH) is a precipitation-hardening martensitic stainless steel that has excellent mechanical properties and corrosion resistance. These characteristics make the STS630 to be used as a consisting material for various components such as spider, pin, spring, and spring retainer, of the control rod drive mechanism (CRDM) in pressurized water reactors (PWRs). In general, it is well known that the oxide layer of stainless steel consists of a duplex layer, a compact inner layer of FeCr₂O₄ spinel, and a coarse-grained outer layer of Fe₃O₄ spinel in PWR primary coolant condition. However, the characteristics of the oxide layer can be sensitively influenced by various water chemistry conditions such as temperature, dissolved oxygen, dissolved hydrogen, pH, pH adjuster type, and exposure time. In this work, we investigate the corrosion properties of the STS630 as a function of coolant temperature in an NH3 alkaline solution for its boron-free application in a small modular reactor, to confirm the feasibility for usage as a boron-free SMR structural material. As a result, oxide layer of corroded STS630 is consist of double-layer oxides consisting of a Cr-rich dense inner oxide and a Fe-rich polyhedral outer particles like as that in commercial PWR primary coolant. The corrosion rate of STS630 increases with increase in test time and temperature and the corrosion rate-time model equation was developed based on experimental data. Overall, it is expected that the results in this study provides useful data for the corrosion behavior of STS630 in alkaline environments, contributing to the development of selecting suitable materials for SMRs.

• Toxicological Research
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• v.17
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• pp.323-327
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• 2001

March 19, 1999, the renovation qf the runway of the Bo-Fai ai1field in Hua Hin, Prachubk-erikhan, Thailand, unearthed chemicals which were left over from the project "anch Hand Operation" held during the Vietnam war era. The chemical mixtures were analyzed by the US EPA, the Department oj Medical Sciences (DMSc), Ministry oj Public Health (MoPH) and the Pollution Control Department (PCD), the Ministry oj Science Technology and Environment (MOSTE) of Thailand, The samples were found to contain several defoliants used in the operation. They were 2,4-D, 2,4,5-T, Dicamba, Cocydelic acid, and Dioxins. Due to the complexity of the issue, the multiplicity of possible health effects, and the socio-economic implications for imports and exports, the Thai Society of Toxicology submitted a proposal to request World Health Organization (WHO), Geneva. The assistance is for the area of chemical safety and called for immediate action to explore the magnitude qf risk involved with Dioxins. In this paper we present our approach to health risk assessment which takes into an account the epidemiological studies of high-risk group exposed to the Ranch Hand operation. Dioxins are endocrine disruption chemicals which public concerns are developed due to presumption that a hazard exists (www.eva.gov/dioxins/html) for which current methodologies are deemed insufficient. The recent concepts of how oxidative stress toxicants may affect health end points and biomarkers of exposure of exposed individuals are discussed. While research activities are undergoing, The Thai Society of Toxicology do not anticipate significant risk to local residents and the environment due to our concurrence with opinion from the international experts invited by the World Health Organization proposed to the local experts at a workshop in Bangkok.n Bangkok.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.89-94
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• 1985

Seventy nine swollen commercially canned grapes and peaches were collected from wholesale and retail outlets in Seoul area for the investigation of the causes of their swell. Hydrogen generation and microbial spoilage were the only two common causes of can swelling. Nevertheless, the spoilage profile of the two products was different. Seventeen out of twenty one canned peaches were spoiled by microorganisms, while the rest of five were swollen due to hydrogen generation. In contrast, fifty one out of fifty eight canned grapes were swollen due to hydrogen generation, while the rest of seven were spoiled by microorganisms. Seventeen yeast and five bacterial strains were isolated and only the yeasts were identified to their genera and species. Saccharomyces cerevisiae was the most frequently isolated spoilage yeast, closely followed by Torulopsis stellata. Candida parapsilosis, Pichia kluyveri, Pichia membranaefaciens, Torulopsis globosa and Torulopsis lactis-condensi were also isolated but with lower frequencies.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.95-105
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• 2014

Dosangugok is located at Dosan-myeon, Andong City, Gyeongbuk and its original landscape was analyzed based on Valley4 Buncheon among Dosangugok. In order to estimate original landscape of Dosangugok, landscape elements were extracted after investigating ancient literatures including 'Nongamjib' and poetry/prose relevant to Dosangugok, landscape elements that could be confirmed at local site survey were suggested and arrangement of Buncheon village was estimated based on painting works. In analysis of poetry/prose, 29 landscape elements were extracted and as a result of local site survey, 6 places including Jeomam (Jari-bawi), Nongam (Gwimeok-bawi), Sajaseok (Saja-bawi), Sangam (Elephant rock), Dae and Bungang were confirmed to be existed at present and in painting works, Rocks such as Aeildang on the rock adjacent to Bungang, Buncheon Seowon at its backyard village, Bungang Byeoneui Gwimeokbawi, Jeomam were confirmed to be expressed even though not expressed in detail. Survey was performed based on ancient site of Nongam head house in parallel with interview with 17th eldest grandson(Ph.D. Lee, sung won)of Nongam Lee, Hyeon Bo and local site survey and original landscape was reproduced by making its result as a drawing and preparing an estimated map around this area.

• Korean Journal of Poultry Science
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• v.19 no.4
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• pp.197-204
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• 1992

This study was divided into experiment 1(191 g egg-albumen plus 150g sucrose) and experiment 2(222g egg-albumen plus 150g sucrose)which were subdivided into groups treated with 0, 8.71, 17.43 and 26.149 egg yolk. These experiments were incubated in a shaking water bath($50^{\circ}C$ ) with a speed of 92(turnaround) per minute (or a period of times. The pH and specific gravity were measured after 2, 4, 6, 8, 10 and 12 hours incubation. The results obtained were as follows ： 1. The pH and specific gravity were steadily increased by shaking time, but decreased by the amount of egg yolk. 2. In the groups treated with egg-albumen, egg yolk, and sucrose of experiments 1 and 2, PH was increased by shaking time and reached highest value at 10 hours shaking time. However, after 12 hours shaking time pH slightly decreased though not significantly. 3. In the experiment 1 and 2, specific gravity had a higher correlation with pH and the regression equation between specific gravity and pH (X) were Y＝0.1081x+0.272(r＝0.899n) and Y＝0.083X＋0.476(r＝0.825$^{* *}$), respectively.y.

• KSBB Journal
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• v.17 no.4
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• pp.381-387
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• 2002

A filamentous fungus, strain FB01 showing high $\beta$-glucosidase activity was isolated from a compost. This fungus was cocultured with Trichoderma viride to enhance the productivity of $\beta$-glucosidase by changing inoculation time of the fungus. The microbial consortium showed higher cellulolytic enzyme production than T. viride alone. The maximal enzyme production was obtained when the microbial consortium was cultured at 30$\^{C}$ and pH 6.0 for 10 days with the activities of CMCase, $\beta$-glucosidase, and avicelase of 2.0, 0.8, and 0.2 U/mL, respectively. These enzyme activities were 2, 4, and 2 times as high as those of CMCase, p-glucosidase, avicelase from T. viride, respectively, indicating that a synergistic interaction appeared between T. viride and strain FBOI . The serial subcultures with pH control increased $\beta$-glucosidase production about 3.2 times. Enzyme production using ricestraw as a carbon source showed that the activities of CMCase, $\beta$-glucosidase, and avicelase were 3.69, 0.76, 0.17 U/mL, respectively, and $\beta$-glucosidase activity was 1.5 times higher than that of T viride.

• Korean Journal of Poultry Science
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• v.19 no.1
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• pp.1-12
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• 1992

This study was divided into experiment I(129g egg-albumen plus 150g sucrose) and experiment II(161g egg-albumen plus 150g sucrose) which were subdivided into groups treated with 0, 8.71, 17.43 and 26.149 egg yolk. These experiments were incubated in a shaking water bath(5$0^{\circ}C$) with a speed of 92(turnaround) per minute for a period of times. The pH and specific gravity were measured after 2, 4, 6, 8, 10 and 12 hour incubations. The results obtained were as follows： 1. The pH and specific gravity were steadily increased by shaking time, but variably was influenced by the amount of egg yolk and egg-albumen. 2. In the groups treated with egg-albumen, egg yolk, and sucrose of experiments I and II, pH was increased by the amount of egg-albumen in conjunction with shaking time, but specific gravity was decreased. 3. Ten hours after shaking maximum pH 8.60 was shown in the groups treated with 161g egg-albumen ： however, in ：he groups treated with 129g egg-albumen the maximum pH 8.39 was shown 12 hours after shaking. The different time exhibited maximum pH resulted from the amount of egg-albumen used. 4. The pH specific gravity were higher in the ,groups treated without egg yolk than in the groups with egg yolk. 5. In the experiment I which was added four levels of egg yolk to 1509 of sucrose and 129g of egg albumen, specific gravity(Table 2) had a high (r＝0.9692$^{* *}$) correlation with pH (Table 1) and the regression equation between specific gravity and pH (X) was Y＝0.050＋0.145x. 6. In the experiment II which was added four levels of egg yolk to 150g of sucrose and 161g of egg albumen, specific gravity(Table 4) had a high (r＝0.8963$^{* *}$) correlation with pH (Table 3) and the regression equation between specific gravity and pH (X) was Y＝0.294＋0.110X.10X.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.326-333
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• 2009

Heterocyclic aromatic amines (HCAs) are mutagenic and carcinogenic substances that are formed during the heating of protein-rich foods. HCAs are generally found at low amounts in a complex matrix, which requires sophisticated analysis. In this study, HCAs were extracted from lyophilized fish and shellfish samples using solid-phase extraction (SPE) and determined by liquid chromatography-electrospray ionization/mass spectrometry (LC-ESI-MS). The HCA recoveries in the fish and shellfish ranged from 15.7 to 74.7% with standard deviations from 0.2 to 7.63%. And HCA concentrations ranged from 0.8 to 1,117.7 $ng/g^{-1}$ in cooked food samples. 1-methyl-9H-pyrido[3,4-b]indole (Harman), 9H-pyrido[3,4-b]indole (Norharman), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) were the most abundant HCAs formed in the muscle of fried mackerel, at levels of 1,117.7, 926.6, and 133.7 ng/g, respectively. 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 2-aminodipiryrido[1,2-a:3,2-d]imidazole(Glu-P-2), 2-amino-9H-pyrido[2,3-b]indole(A${\alpha}$C), 2-amino-3methyl-9H-pyrido [1,2-a:3,2-d]imidazole(MeA${\alpha}$C), 2-amino-3,4,7,8-tetramethylimidazo[4,5-f]quinoxaline (TriMeIQx), 2-amino-3,7,8-trimethylimidazo [4,5-f]quinoxaline(7,8-DiMeIQx), and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) were only detected by small quantities ranged from 1.5 to 98.6 ng/g. Overall, this study provides useful information on HCA levels in fish and shellfish products consumed in Korea.

• Informatization Policy
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• v.17 no.4
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• pp.3-22
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• 2010

The purpose of this study is to provide the fruitful directions for the future studies on smart work by analyzing the past and present trends that are related to smart work. For this, a wide range of materials and MA and PhD treatises produced from 1992 to the present have been collected and have been analyzed on the basis of various standards, including objective of study, approach method, methodology, method of data collection, statistical technique of analysis, summary of problems and alternativesto overcome limitations. Lessons and implications of this study for the possibility of smart work are presented. I hope this study will contributeto future studies concerned about smart work.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.934-944
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• 2007

Paenibacillus polymyxa E681 is known to be able to suppress plant diseases by producing antimicrobial compounds and to promote plant growth by producing phytohormones, and secreting diverse degrading enzymes. In spite of these capabilities, little is known regarding the flow of information from the bacterial strain to the barley roots. In an attempt to determine the flow of information from the bacterial strain to barley roots, the strain was grown in the presence and absence of barley, and two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and MALDI-TOF mass spectrometry were used. 2D-PAGE detected approximately 1,000 spots in the cell and 1,100 spots in the supernatant at a pH 4-10 gradient. Interestingly, about 80 spots from each sample showed quantitative variations. Fifty-three spots from these were analyzed by MALDI-TOF mass spectrometry and 28 proteins were identified. Most of the cytosolic proteins expressed at higher levels were found in P. polymyxa E681 cells grown in the presence of barley rather than in the absence of barley. Proteins detected at a lower level in the surpernatant of P. polymyxa E68l cells grown in the presence of barley were lipoprotein, glucose-6-phosphate 1-dehydrogenase, heat-shock protein HtpG, spermidine synthase, OrfZ, ribonuclease PH, and coenzyme PQQ synthesis protein, and flagellar hook-associated protein 2 whereas proteins detected at a higher level in the surpernatant of P. polymyxa E681 cells grown in the presence of barley included D-alanyl-D-alanine ligase A, isopentenyl-diphosphate delta-isomerase, ABC transporter ATP-binding protein Uup, lipase. Many of the proteins belonging to plant-induced stimulons are associated with biosynthetic metabolism and metabolites of proteins and transport. Some of these proteins would be expected to be induced by environmental changes resulting from the accumulation of plant-secreted substances.