• Title/Summary/Keyword: 기간분리

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Determination of Ethyl Carbamate in Commercial and Homemade Maesilju (매실주의 에틸카바메이트 분석)

  • Ryu, Dayeon;Koh, Eunmi
    • Journal of the East Asian Society of Dietary Life
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    • v.25 no.2
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    • pp.309-315
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    • 2015
  • This study aimed to develop and validate an analytical method for ethyl carbamate (EC) in Maesilju. For accurate analysis of EC in Maesilju, an internal standard (d5-EC) and neutralization (pH=7) were performed. The limit of quantification (LOQ) was 3.65 ppb while the recovery rate ranged from 92.54% to 103.59%. Intra- and inter-day precision ranged from 0.87% to 1.99% and 2.67% to 5.64%, respectively. Maesilju samples comprised 10 homemade and five commercial ones. Samples contained EC at levels between 118.48 and 2,640.42 ppb. The average content of homemade Maesilju was higher than those of commercial ones. Based on manufacturers' labeling of commercial samples and information on homemade samples, various factors such as ingredients and soaking time of Maesil affected EC level in Maesilju. EC contents showed a positive correlation with age of Maesilju.

Flavor Components of Barley Meju manufactured with barley bran (보리등겨로 제조한 메주의 향기성분)

  • Choi, Ung-Kyu;Son, Dong-Hwa;Kwon, O-Jun;Lee, Eun-Joung;Kwak, Dong-Ju;Gwon, O-Jin;Chung, Yung-Gun
    • Applied Biological Chemistry
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    • v.43 no.3
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    • pp.196-201
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    • 2000
  • This study was conducted to investigate various flavor components of barley meju during fermentation. The change of PH was $5.2{\sim}5.6$. L-value and b-value gradually decreased. a-value gradually increased until fifth day and then decreased. Among 75 flavor compounds identified in barley meju, 10 aldehydes and 10 ketones were most in number followed by 9 acids, 9 phenols, 7 hydrocarbons, 7 alcohols and 6 esters. The contents of ethyl acetate $(67.8{\sim}89.1%)$ was more than those of any ether component followed by hexadecanoic acid $(1.21{\sim}12.00%)$ and tetramethylpyrazine $(0.06{\sim}12.30%$).

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Prediction of Thermal-Hydraulic Phenomena in the LBLOCA Experiment L2-3 Using RELAP5/MOD2 (RELAP5/MOD2 코드에 의한 대형냉각재 상실사고 모사실험 L2-3의 열수력 현상 예측)

  • Bang, Young-Seok;Chung, Bub-Dong;Kim, Hho-Jung
    • Nuclear Engineering and Technology
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    • v.23 no.1
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    • pp.56-65
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    • 1991
  • The LOFT LOCE L2-3 was simulated using the RELAP5/MOD2 Cycle 36.04 code to assess its capability in predicting the thermal-hydraulic phenomena in LBLOCA of a PWR. The reactor vessel was simulated with two core channels and split downcomer modeling for a base case calculation using the frozen code. The result of the base calculation showed that the code predicted the hydraulic behavior, and the blowdown thermal response at high power region of the core reasonably and that the code had deficiencies in the critical How model during subcooled-two-phase transition period, in the CHF correlation at high mass flux and in the blowdown rewet criteria. An overprediction of coolant inventory due to the deficiencies yielded the poor prediction of reflood thermal response. Improvement of the code, RELAP5 / MOD2 Cycle 36.04, based on the sensitivity study increased the accuracy of the prediction of the rewet phenomena.

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Characteristics and breeding of 'Yeoreumhyang1ho': a new light brown variety of Flammulina velutipes adaptable to high temperature (고온성 연갈색 팽이버섯 신품종 '여름향1호'의 육성 및 특성)

  • Kim, Min-Ja;Lee, Kwan-Woo;Chang, Who-Bong;Jeon, Jong-Ock;Kim, Ik-Jei
    • Journal of Mushroom
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    • v.16 no.4
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    • pp.287-292
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    • 2018
  • 'Yeoreumhyang1ho' - a new variety of Flammulina velutipes, light brown in color and adaptable to high temperature - was bred by mating two monokaryons isolated from 'Garlmoe' and 'Konkuk1ho'. It exhibited better quality compared to 'Geumhyang' and 'Garlmoe' under conditions where temperature was maintained at $16^{\circ}C$, without exposure to low temperature ($4^{\circ}C$), during the cultivation period. Bottle cultivation at $16^{\circ}C$ required 22, 6, and 10 days for mycelial growth, primordia formation, and growth of the fruit body, respectively. The total cultivation period for 'Yeoreumhyang1ho' was observed to be 38 days, which is 3 and 7 days shorter than that for 'Geumhyang' and 'Garlmoe', respectively. The primordia formation showed remarkable uniformity and the pileus color was observed to be light brown, an intermediate between yellowish ivory of 'Geumhyang' and medium brown of 'Garlmoe'. The yield was 138 g per 850 ml bottle, which was 10% higher than that of 'Geumhyang'.

A study on the Changes in the water level-flow relationship curve due to the operation of movable beams and the influence of construction (가동보 운영과 공사영향에 의한 수위-유량 관계곡선식의 변화)

  • Ok, Young Jun;Jo, Kyung Min;Lee, Jung Hoon;Kim, Seung Hyun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.421-421
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    • 2022
  • 만경강 유역은 우리나라의 농업지역 중 하나로 많은 농업용수를 필요로 하는 지역으로 농업용수 공급을 위하여 다수의 취입보가 설치되어 있으며, 충분한 농업용수 확보를 위하여 다른 지역과 달리 가동보와 고정보가 병설로 설치되어 있는 곳이 많다. 통상적인 가동보는 농업용수 확보와 공급을 위하여 농번기인 4월~9월까지 운영되는 것이 일반적이며, 이러한 가동보 운영으로 인하여 다양한 수위-유량관계의 변동성이 발생한다. '20년부터 전주천에 위치한 취입보는 과거와 달리 기존의 월류 높이가 높은 보의 형태에서 어도가 넓고, 보의 높이가 낮은 친환경 월류보의 형태로 전환이 이루어지고 있으며, 그 영향으로 인하여 과거의 수위-유량관계와는 상이한 결과가 발생한다. 하도의 변동성은 단면 측량 등으로 확인 할 수 있으나, 가동보 운영과 공사와 같이 통제특성에 의한 변동사항이 발생하는 경우 모니터링이 필수적이다. 본 연구에서는 만경강 유역에 위치한 전주시(미산교)관측소를 대상관측소로 선정하였으며, 대상관측소는 '20년 12월~'22년 1월까지 친환경 월류보 전환을 위하여 가동보 운영과 공사가 진행된 관측소이다. '20년 12월 친환경 월류보 형태의 전환을 위하여 가동보 운영을 시작하였으며, '21년은 1월~3월은 유지유량을 위한 가동보 운영을 실시하였으며, 4월~9월은 농업용수 확보를 위한 가동보 운영을 실시하였고, 10월~12월은 하도 내 공사 진행에 따라 가동보와 고정보를 같이 운영하였다. 이 기간동안 가동보와 고정보 모니터링을 실시하였으며, 정확한 유량측정성과와 곡선식 확인을 위하여 동일한 위치에서 측정을 수행하였다. 가동보 운영과 공사영향 모니터링 결과와 유량측정성과를 바탕으로 수위-유량관계 변화를 분석하였으며, 저수위 구간은 가동보 운영에 따라 총 11차례 기간분리가 발생하였으며, 중수위 구간도 가동보 운영으로 인하여 과거와 상이한 경향이 발생하여 곡선식을 재개발 하였다. 결과적으로 본 연구에서는 가동보 운영에 따른 다수의 유량측정성과를 확보하였으며, 확보한 유량측정성과의 분석을 통한 신뢰도 높은 수위-유량관계곡선식을 개발하였고 이를 통해 생산된 유량자료는 정확도가 매우 높은 것으로 분석되었다.

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Role of the Inferior Thyroid Vein after Left Brachiocephalic Vein Division During Aortic Surgery

  • Park, Hyung-Ho;Kim, Bo-Young;Oh, Bong-Suk;Yang, Ki-Wan;Seo, Hong-Joo;Lim, Young-Hyuk;Kim, Jeong-Jung
    • Journal of Chest Surgery
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    • v.35 no.7
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    • pp.530-534
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    • 2002
  • Background: In aortic surgery, division and ligation of the left brachiocephalic vein(LBV) may improve exposure of the aortic arch but controversy continues about the safety of this division and whether a divided vein should be reanastomosed after arch replacement was completed. The safety of LBV division and the fate of the left subclavian venous drainage after LBV division were studied. Material and Method: From November 1998 to January 2001, planned division and ligation of the LBV on the mid-line after median sternotomy was peformed in 10 patients during the aortic surgery with the consideration of local anatomy and distal aortic anastomosis. Assessment for upper extremity edema and neurologic symptoms, measurement of venous pressure in the right atrium and left internal jugular vein, and digital subtraction venography(DSV) of the left arm were made postoperatively. Result: In 10 patients there was improvement in access to the aortic arch for procedures on the ascending aorta or aortic arch. The mean age of patients was 62 years(range 24 to 70). Follow-up ranged from 3 weeks to 13 months. One patient died because of mediastinitis from methicilline-resistant staphylococcus aureus strain. All patients had edema on the left upper extremity, but resolved by the postoperative day 4. No patient had any residual edema or difficulty in using the left upper extremity during the entire follow-up period. No patient had postoperative stroke. Pressure difference between the right atrium and left internal jugular vein was peaked on the immediate postoperative period(mean peak pressure difference = 25mmHg), but gradually decreased, then plated by the postoperative day 4. In all DSV studies left subclavian vein flowed across the midline through the inferior thyroid venous plexus. Conclusion: We conclude that division of LBV is safe and reanastomosis is not necessary if inferior thyroid vein, which is developed as a main bridge connecting the left subclavian vein with right venous system, is preserved.

Clinical Significance of Enterovirus in Febrile Illness of Young Children (하절기에 발열을 주소로 입원한 3개월 이하의 영아에서 장바이러스 감염)

  • Kwak, Ji-Yeon;Cho, Mi-Hyun;Kim, Sung-Eun;Kang, Suk-Ho;Kim, Mi-Ok;Ma, Sang-Hyuk;Lee, Kyu-Man
    • Pediatric Infection and Vaccine
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    • v.8 no.1
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    • pp.94-100
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    • 2001
  • Purpose : Enterovirus is a common cause of aseptic meningitis and nonspecific febrile illness in young children. During the summer and fall months, enterovirus-infected young children are frequently admitted and evaluated to rule out bacterial sepsis and/or meningitis. The purpose of this study was to evaluate the relationship between nonpolio enterovirus infection and febrile illness in infants under 3 months of age during the summer, fall months by using a stool culture to identify the presence of enterovirus. Methods : Patients included febrile infants under 3 months of age admitted to Masan Fatima Hospital for sepsis evaluation from May 1999 to September 1999. Cultures were performed from stool and Cerebrospinal fluid samples and then were tested for enterovirus infection. Viral isolation and serotype identification were performed by cell culture and immunofluorescent testing. Enteroviruses not typed by immunofluorescent testing were confirmed by reverse transcription-polymerase chain reaction. Results : A total of 44 febrile infants were enrolled; of those, 20(45%) were positive for enterovirus. Two enterovirus culture-positive infants had concomitant urinary tract infection and one had Kawasaki disease. All infants infected with an enterovirus recovered without complications. Serotype of 20 enteroviruses were isolated from stool, 3 of echovirus type 9, 1 of echovirus type 11, 1 Coxsachievirus type B4, 15 of untyped enteroviruses. One untyped enterovirus was isolated in the CSF. Conclusion : Nonpolio enterovirus infections are associated with nonspecific febrile illnesses in infants under 3 months of age.

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Effect of Microbial Phytase in Low Phosphorus and Calcium Level Diet on the Performance and Nutrient Digestibility in Laying Hens (인과 칼슘의 수준이 낮은 산란계 사료 내 미생물 Phytase의 첨가가 생산성 및 영양소 소화율에 미치는 영향)

  • Min B.J.;Kwon O.S.;Lee W.B.;Son K.S.;Hong J.W.;Yang S.J.;Moon T.H.;Kim I.H.
    • Korean Journal of Poultry Science
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    • v.32 no.1
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    • pp.15-21
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    • 2005
  • This Study was conducted to investigate the effects of microbial phytase in low phosphirus and calcium level diet on the performance and nutrient digestibility in laying hens. One hundred ninety two, 50 wks old, ISA brown commerical layers were used for 12 weeks feeding trial after 7-d adjustment period. Four dietary treatments included CON(control; Co.), P2 ($0.06\%$ Natuphos, BASF) and P3 ($0.06\%$ PHOSMAX, GENOFOCUS). Ca and available P concentrations of P1, P2 and P3 were 90 and $50\%$ of NRC recommecdations to accentuate difference in response to phytase availability. In whole period, egg production was not affected by treatments. At 12 weeks, egg weight was significantly increased in adding phytase treatments (P<0.05). Egg shell thickness was increased in P1, P2 and P3 treatments compared with control (P<0.05) at 9 weeks. Ca concentration of serum tended to decrease in P1 treatment without significant difference (P>0.05). Ca and P concentrations of tibia were higher in layers fed dietary phyrase than those fed control diet without significant difference (P>0.05). Digestibilities of DM, N and ash were improved in P1 treatment compared with P2 and P3 treatments (P<0.05). Ca and P digestibilities were the highest in P2 treatment (P>0.05), but was not significant difference between control and P1 treatments.

Studies on the Changes of Chemical Components of Dried Jujube (Zizyphus jujuba MILLER) during Storage (대추 (Zizyphus jujuba MILLER)의 저장중(貯藏中) 화학성분변화(化學成分變化)에 관(關)한 연구(硏究))

  • Lee, Hee Bong;Kim, Seung Yeol
    • Korean Journal of Agricultural Science
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    • v.15 no.1
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    • pp.95-113
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    • 1988
  • In order to find out changes of chemical components related to browning of dried jujube, four varieties were subjected to the proximate analysis. Boeun, one of the major varieties in Korea, was sun-dried and stored for 12 months and analyzed periodically for one year. Browning, titrable acidity, pH, contents of ascorbic acid, organic acid, total amino acid, free amino acid, free sugar, hydroxymethylfurfural (HMF) and phenolic compounds were determined and compared with those of fresh jujube. The results obtained are summarized as follows; 1. In comparison with other similar fruits, jujube was high contents of ascorbic acid (62-79mg%) and carbohydrate (22-28%) excluding fiber. 2. Browning was increased in both steam-treated and nontreated plot together as storage period was prolonged. 3. Ascorbic acid content of fresh jujube was as high as 297.4mg% DB, but it was decreased to 20.2mg% DB, after 12 months storage. Therefore, loss of ascorbic acid was very great up to 93% of its original content. 4. Five kinds of organic acid, oxalic, succinic, fumaric, malic and citric acid were identified as major organic acids. It was interesting that only fumaric acid content was increased while others decreased during storage. 5. Seventeen kinds of amino acid were identified in the analysis of total amino acid content. Major amino acids were found to be proline, threonine, glutamic acid and lysine. During 12 months storage, 30% of original total amino acid was decreased and this was mostly accounted for free amino acids. 6. Threonine, proline, alanine and valine were identified as free amino acids which showed 85% decrease after 12 months storage. 7. Free sugars of jujube were composed of fructose, glucose and sucrose. They showed 24% decrease after 12 months storage, Especially sucrose was not detected after 4 months storage. 8. HMF of dried jujube was isolated and identified. Its content was increased up to great extent as storage period prolonged. 9. Caffeic, ferulic and P-coumaric acid were identified as jujube phenolic compounds which were significantly decreased during storage. In conclusion, non-enzymatic browning was thought to be more important than enzymatic reaction in the dried jujube. Amino-carbonyl reaction, ascorbic acid oxidation and reaction between phenolic compounds and sugar or nitrogen compounds were observed to be related to this browning.

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Isolation and identification of a tricin 4"-O-(threo-β-guaiacylglyceryl) ether producing microorganism from germinated rice (발아 벼로부터 tricin 4"-O-(threo-β-guaiacylglyceryl) ether 생성균주의 분리 및 동정)

  • Yoon, Nara;Jang, Gwi Yeong;Lee, Yoon Jeong;Li, Meishan;Kim, Min Young;Kim, Hyun Young;Lee, Junsoo;Jeong, Heon Sang
    • Korean Journal of Food Science and Technology
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    • v.48 no.4
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    • pp.361-365
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    • 2016
  • This study was conducted to isolate and identify a microorganism that increases tricin-O-(threo-${\beta}$-guaiacylglyceryl) ether (TTGE) content in the hulls of rice (Oryza sativa L.). Bacteria from germinated rice were isolated by enrichment cultivation using yeast mold, luria bertani, potato dextrose and mannitol egg york polymyxin broths. The highest increase in TTGE content ($339.30{\mu}g/g$) was achieved by a microorganism isolated by PDA enrichment cultivation. On the basis of 16S RNA sequence homology and phylogenetic analysis, the isolated bacterium was identified to have 100% similarity with Burkholderia vietnamiensis. The isolated bacteria were short rods, negative for the Gram stain, and positive for the catalase test. The highest TTGE level was $435.86{\mu}g/g$ in 72-h fermented samples, representing a 2.5x increase compared with the control ($175.65{\mu}g/g$). In conclusion, the bacterium isolated from germinated rice extract was Burkholderia vietnamiensis, and the optimum fermentation period to maximize TTGE levels was 72 h. These findings might help in developing functional materials using rice hulls, a waste product of rice milling.