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Petrological Study on the Cretaceous Volcanic Rocks in the southwest Ryeongnam Massif: (1) the Mt. Moonyu volcanic mass, Seungju-gun (영남육괴 남서부에 분포하는 백악기 화산암류에 대한 암석학적 연구: (1) 승주군 문유산 화산암복합체)

  • Kim, Young-La;Koh, Jeong-Seon;Lee, Jeong-Hyun;Yun, Sung-Hyo
    • The Journal of the Petrological Society of Korea
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    • v.17 no.2
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    • pp.57-82
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    • 2008
  • The volcanic sequence of the late Cretaceous Moonyu volcanic mass which distributed in the southwestern part of Ryeongnam massif, can be divided into felsic pyroclastic rocks, andesite and andesitic pyroclastic rocks, rhyolite in ascending order. The earliest volcanic activity might commence with intermittent eruptions of felsic magma during deposition of volcaniclastic sediments. Explosive eruptions of felsic pyroclastic rocks began with ash-falls, to progressed through pumice-falls and transmitted with dacitic to rhyolitic ash-flows. Subsequent andesite and andesitic pyroclastic rocks were erupted and finally rhyolite was intruded as lava domes along the fractures near the center of volcanic mass. Petrochemical data show that these rocks are calc-alkaline series and have close petrotectonic affinities with subduction-related continental margin arc volcanic province. Major element compositions range from medium-K to high-K. Petrochemical variation within the volcanic sequence can be largely accounted for tractional crystallization processes with subordinate mixing. The most mafic rocks are basaltic andesite, but low MgO and Ni contents indicate they are fractionated by fractional crystallization from earlier primary mafic magma, which derived from less than 20% partial melting of ultramafic rocks in upper mantle wedge. Based on the stratigraphy, the early volcanic rocks are zoned from lower felsic to upper andesitic in composition. The compositional zonation of magma chamber from upper felsic to lower andesitic, is interpreted to have resulted from fractionation within the chamber and replenishment by an influx of new mafic magma from depth. Replenishment and mixing is based on observations of disequilibrium phenocrysts in volcanic rocks. REE patterns show slight enrichment of LREE with differentiation from andesite to rhyolite. Rhyolite in the final stage can be derived from calc-alkaline andesite magma by fractional crystallization, but it might have underwent crustal contamination during the fractional crystallization.

A Study on the Carbothermic Reduction and Refining of V, Ta and B Oxides by Ar/Ar-H2 Plasma (Ar/Ar-H2 플라즈마에 의한 V, Ta, B 산화물의 탄소용융환원 및 정련)

  • Chung, Yong-Sug;Park, Byung-Sam;Hong, Jin-Seok;Bae, Jung-Chan;Kim, Moon-Chul;Baik, Hong-Koo
    • Transactions of the Korean hydrogen and new energy society
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    • v.7 no.1
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    • pp.81-92
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    • 1996
  • The Ar/Ar-$H_2$ plasma method was applied to reduce oxides and refine metals of V, Ta and B. In addition, the high temperature chemical reaction in Ar plasma and of the refining reaction in the Ar-(20%)$H_2$ plasma were analyzed. The crude V of 96wt% purity was obtained at the ratio of $C/V_{2}O_{5}=4.50$ by the Ar plasma reduction grade and the maximum reduction was obtained at $C/V_{2}O_{5}=4.50$ due to the $O_{2}$ loss from the thermal decomposition of vanadium oxide. In the Ar-(20%)$H_2$ plasma refining, the metallic V of 99.2wt% was produced at the ratio of $C/V_{2}O_{5}=4.40$. It was considered that a main refining reaction resulted from the chemical reaction between the residual carbon and residual oxygen. The metallic Ta of 99.8wt% was obtained at the ratio of $C/Ta_{2}O_{5}=5.10$ in a Ar plasma reduction and the Oz loss from the thermal decomposition of tantalum pentoxide did not take place. The deoxidation reaction was more significant than the decarburization reaction in the Ar-(20%)$H_2$ plasma refining and the metallic Ta of 99.9wt% was produced within the range of $C/Ta_{2}O_{5}$ ratio of 4.50 to 5.10. The Vickers hardness of Ta in the above mentioned range was about 220Hv due to the decrease in a residual oxygen by the deoxidation reaction. On the other hand, C is no suitable agent for the reduction of $B_{2}O_{3}$ by the Ar and Ar-$H_2$ plasma. But Fe-B-Si alloy was produced with the reduction of $B_{2}O_{3}$ in the melt when Fe, C, $B_{2}O_{3}$, and ferroboron mixtures were melted by the high frequency induction melting.

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Optimization of Production Medium by Response Surface Method and Development of Fermentation Condition for Monascus pilosus Culture (Monascus pilosus 배양을 위한 반응표면분석법에 의한 생산배지 최적화 및 발효조건 확립)

  • Yoon, Sang-Jin;Shin, Woo-Shik;Chun, Gie-Taek;Jeong, Yong-Seob
    • KSBB Journal
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    • v.22 no.5
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    • pp.288-296
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    • 2007
  • Monascus pilosus (KCCM 60160) in submerged culture was optimized based on culture medium and fermentation conditions. Monacolin-K (Iovastatin), one of the cholesterol lowing-agent which was produced by Monascus pilosus may maintain a healthy lipid level by inhibiting the biosynthesis of cholesterol. Plackett-Burman design and response surface method were employed to study the culture medium for the desirable monacolin-K production. As a result of experimental designs, optimized production medium components and concentrations (g/L) were determined on soluble starch 96, malt extract 44.5, beef extract 30.23, yeast extract 15, $(NH_4)_2SO_4$ 4.03, $Na_2HPO_4{\cdot}12H_2O$ 0.5, L-Histidine 3.0, $KHSO_4$ 1.0, respectively. Monacolin-K production was improved about 3 times in comparison with shake flask fermentation of the basic production medium. The effect of agitation speed (300, 350, 400 and 450 rpm) on the monacolin-K production were also observed in a batch fermenter. Maximum monacolin-K production with the basic production medium was 68 mg/L when agitation speed was 500 rpm. And it was found that all spherical pellets (average diameter of $1.0{\sim}1.5mm$) were dominant during fermentation. Based on the results, the maximum production of 185 mg/L of monacolin-K with the optimized production medium was obtained at pH (controlled) 6.5, agitation rate 400 rpm, aeration rate 1 vvm, and inoculum size 3%.

Comparative Analysis of Quantitative Signal Intensity between 1.0 mol and 0.5 mol MR Contrast Agent (1.0 mol 과 0.5 mol MR조영제의 정량적 신호강도 비교분석)

  • Jeong, Hyun Keun;Jeong, Hyun Do;Nam, Ki Chang;Jang, Geun Yeong;Kim, Ho Chul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.12
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    • pp.134-141
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    • 2015
  • The purpose on this research is quantitatively comparing and analyzing signal intensity of 1.0mol and 0.5mol contrast agent. For this study, two MR phantoms were produced. One of them is used with 1.0mol Gadobutrol. The other is used with 0.5mol Gadoteridol. These two phantoms respectively have been scanned by SE T1 sequence which is used to get a general contrast-enhanced image in 1.5T MRI and 3D FLASH sequence which is used as enhanced angio MRI. Signal intensity was measured by scanned images as per contrast agent dilution ratio. The results were as follow: RSP(Reaction Starting Point) of the two sequences(2D SE, 3D FLASH) was respectively 6.0%, 60.0% in 0.5mol contrast and 2.0%, 20.0% in 1.0mol contrast, which means in 0.5mol contrast, RSP was formed faster than the one in 1.0mol contrast. MPSI was respectively 1358.8[a.u], 1573[a.u] in 0.5mol contrast and 1374[a.u], 1642.4[a.u] in 1.0mol contrast, which means 0.5mol contrast's MPP (0.4%, 10.0%) was formed faster than 1.0mol contrast's MPP (0.16%, 1.8%). Lastly, RA as per contrast agent dilution ratio was 27.4%, 11.8% wider in 0.5mol contrast(20747.4[a.u], 23204.6[a.u]) than in 1.0mol contrast(12691.9[a.u], 20747.4[a.u]). According to the study, we are able to assure that signal reaction time of 1.0mol contrast is slower than the one of 0.5mol contrast in contrast-enhanced MRI at two different sequences(2D SE, 3D FLASH). Furthermore, owing to the fact that there are not any signal intensity differences between 1.0mol and 0.5mol contrast, it is not true that high concentration gadolinium MR contrast agent does not always mean high signal intensity in MRI.

Analysis of Aconitine Contents in Aconiti Radix Lateralis Preparata and Sambutang-P that Contains Aconiti Radix Lateralis Preparata and Single Oral Toxicity Test (포제부자(炮製附子) 및 포제부자(炮製附子) 함유 삼부탕(蔘附湯)의 aconitine 함량 분석과 단회투여 독성시험)

  • Bae, Jeong Hu;Kim, Gyeong Cheol;Shin, Soon Shik;Hwang, Won Deuk
    • Herbal Formula Science
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    • v.25 no.1
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    • pp.11-28
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    • 2017
  • Objectives : The contents of aconitine in aconiti radix lateralis preparata, purified hot water extract of Aconiti Radix lateralis preparata, and purified hot water extract of Sambutang-P that contains Aconiti Radix lateralis preparata was analyzed to compare toxicity. Toxicity of Sambutang-P that contains Aconiti Radix lateralis preparata was assessed with a single oral toxicity test on 6-week-old male and female Sprague-Dawley rats. Methods : 1. The contents of aconitine in Aconiti Radix lateralis preparata, purified hot water extract of Aconiti Radix lateralis preparata, and purified hot water extract of Sambutang-P that contains Aconiti Radix lateralis preparata was analyzed using the purity test according to the "Korean Herbal Pharmacopoeia". 2. 2,000mg/kg was injected for the single oral toxicity test of purified hot water extract of Sambutang-P that contains Aconiti Radix lateralis preparata, and the test was done for a test group (injection) and a control group, each with 5 male and 5 female rats. For 14 days after injection, rats were observed for general symptoms and changes in weight. Afterwards, blood biochemical test, autopsy, and histophathological exam of the liver was conducted. Results : 1. The contents of aconitine was 0.0785% for Aconiti Radix lateralis preparata, 0.1510% for purified hot water extract of Aconiti Radix lateralis preparata, and 0.1248% for purified hot water extract of Sambutang-P that contains Aconiti Radix lateralis preparata. 2. There was no death of either male or female rats in both the control group and the test group (injection of 2,000mg/kg). 3. No unusual symptom was observed in both the control group and the test group (injection of 2,000mg/kg). 4. No significant change in weight was observed for both male and female rats in the test group (2,000mg/kg). 5. The histopathological exam of ALT, AST, ALP, GGT and LDH showed no significant changes for both male and female rats in the test group (2,000mg/kg). 6. According to the autopsy results, no visible abnormality of organs or tissues was found in both the control group and the test group (2,000mg/kg). 7. According to the histopathological exam of the liver, the effect of the injected material was not observed for either male or female rats in the test group (2,000mg/kg). Conclusions : The contents of aconitine in Aconiti Radix lateralis preparata was lower for decoction of Sambutang-P with ginseng radix alba than for decoction of only Aconiti Radix lateralis preparata. This suggests that ginseng radix alba can dilute toxicity of Aconiti Radix lateralis preparata. As for a single oral toxicity test of Sambutang-P that contains Aconiti Radix lateralis preparata, no abnormal reaction was observed even when the injection amount far exceeded a toxic dose or a lethal dose. Thus, it is deemed that using Sambutang-P at a clinically prescribed dose would not lead to hepatoxicity.

A Study on the Installation of Groyne using Critical Movement Velocity and Limiting Tractive Force (이동한계유속과 한계소류력을 활용한 수제 설치에 관한 연구)

  • Kim, Yeong Sik;Park, Shang Ho;An, Ik Tae;Choo, Yeon Moon
    • Journal of Wetlands Research
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    • v.22 no.3
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    • pp.194-199
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    • 2020
  • Unlike in the past, the world is facing water shortages due to climate change and difficulties in simultaneously managing the risks of flooding. The Four Major Rivers project was carried out with the aim of realizing a powerful nation of water by managing water resources and fostering the water industry, and the construction period was relatively short compared to the unprecedented scale. Therefore, the prediction and analysis of how the river environment changes after the Four Major Rivers Project is insufficient. Currently, part of the construction section of the Four Major Rivers Project is caused by repeated erosion and sedimentation due to the effects of sandification caused by large dredging and flood-time reservoirs, and the head erosion of the tributaries occurs. In order to solve these problems, the riverbed maintenance work was installed, but it resulted in erosion of both sides of the river and the development of new approaches and techniques to keep the river bed stable, such as erosion and excessive sedimentation, is required. The water agent plays a role of securing a certain depth of water for the main stream by concentrating the flow so much in the center and preventing levee erosion by controlling the flow direction and flow velocity. In addition, Groyne products provide various ecological environments by forming a natural form of riverbeds by inducing local erosion and deposition in addition to the protection functions of the river bank and embankment. Therefore, after reviewing the method of determining the shape of the Groyne structure currently in use by utilizing the mobile limit flow rate and marginal reflux force, a new Critical Movement Velocity(${\bar{U}}_d$) and a new resistance coefficient formula considering the mathematical factors applicable to the actual domestic stream were developed and the measures applicable to Groyne installation were proposed.

Studies on Quality Changes and Antioxidant Activity During the Fermentation of the Salt Fermented Whangseoke (황석어(Collichthys nireatus Jordan et starks) 젓갈의 숙성과정 중 품질변화와 항산화작용에 관한 연구)

  • Kim, Ji-Sang;Moon, Gap-Soon;Lee, Kyung-Hee;Lee, Young-Soon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.2
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    • pp.171-176
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    • 2006
  • The effect of storage temperature on the quality and antioxidative activity Whangseoke sauce was studied over a period of 240 days. Fermented Whangseoke with $25\%$ salt were stored at $25^{\circ}C$. The quality change and antioxidant activity of Whangseoke in linoleic acid emulsion was evaluated with various parameters including acids values, peroxide values, TBA values, reducing sugar, brown color intensity, electron donating ability and reducing power at various time intervals for 240 days of storage. In general, it was observed, in all sample, that peroxide values, brown color intensity, electron donating ability and reducing power gradually increased, while reducing sugar decreased during storage at $25^{\circ}C$. The antioxidative activities of fermented Whangseoke were determined on tile linoleic acid emulsion system. The results showed that Whangseoke had antioxidant activity. These results suggest that antioxidant activity of Whangseoke seemed to influence by Maillard reaction products during the storage periods.

Development of Natural Seasoning using Desalinated Tuna Boiled Extract (탈염된 참치 자숙액을 이용한 천연조미료 개발)

  • KIM Se-Kwon;BYUN Hee-Guk;JEON You-Jin;JOO Dong-Sik;KIM Jong-Bae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.1
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    • pp.75-82
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    • 1999
  • The hydrolysate of desalinated tuna boiled extract (TBE) were prepared by continuous hydrolysis of TBE using a membrane reactor. TBE and tuna boiled extract hydrolysate (TBEH) were isolated depending on molecular weights. The major molecular weight distributions of TBEH-l0K, TBEH-5K and TBEH-lK were 9,800Da, 3,000Da and 990Da, respectively. The amounts of nucleotides and their related compounds of TBE were 3.47 $\mu$mole/g AMP, 23.75 $\mu$mole/g IMP, 9.07 $\mu$mole/g inosine and 1.89 $\mu$mole/g hypoxanthine. Total content of amino acids having desirable taste (glycine, glutamic acid, alanine, proline, aspartic acid, serine) was about $63\%$ of total amino acid from TBE and about $62\%$ from TBEH. The natural seasoninings were prepared with TBE and TBEH. From the results of sensory evaluations, complex seasoning containing TBEH-1K was almost equal to the shellfish complex seasoning obtained from the market. The mixed sauce which was made by mixing of $50\%$ TBEH sauce and $50\%$ fermented soy sauce was similar to the tradition soybean sauce in product quality and it showed the possibility to be used for the substitute product for acid hydrolyzed soysauce.

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Effect of Dietary Supplementation of Alisma canaliculatum (Alismatis Rhizoma) and Viscum album (Mistletoe) on Growth Performance and Immunity in Broiler Chickens (택사와 겨우살이 급여가 육계의 생산성 및 면역성에 미치는 영향)

  • Kim, Ki-Soo;Kim, Gwi-Man;Ji, Hoon;Park, Sung-Uk;Yang, Chul-Ju
    • Korean Journal of Poultry Science
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    • v.38 no.1
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    • pp.21-28
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    • 2011
  • This study was conducted to investigate the effect of dietary supplement of Alisma canaliculatum and Viscum album on the growth performance and immune response of broiler chickens. One hundred and forty Ross broiler chicks (1 day old) were assigned to 4 treatments in 5 replications with 7 birds per replication. The dietary treatments were NC group (without antibiotics), PC group (basal + 50 ppm Oxytetracycline), AC group (basal + Alisma canaliculatum 0.5%), and VA group (basal + Viscum album 0.5%). The results revealed that body weight gain and feed intake were not significantly different among the treatments. Addition of AC to the diet showed significantly higher feed conversion ratios than the VA addition diet and other treatments (p<0.05). The concentration of linolenic acid, ${\alpha}$-linolenic acid and arachidonic acid in the AC and VA treatment were relatively higher than that in the antibiotic treatment, while there was no difference in the concentration of SFA, USFA, and USFA/SFA. The serum IgG concentration in chickens tended to increase in the AC and VA treatment groups compared to NC group. The IL2 concentration in AC and VA groups was significantly higher than in other group (p<0.05). IL6 was not detected, however. GOT, GPT, and T-billirubin in the VA group were significantly higher than in other groups (p<0.05). Thus, the VA additives can result in the damage of liver and kidney. In conclusion, the dietary supplement of a 0.5% of AC and VA showed a similar growth performance and increased immunity response comparable to supplementing a 50 ppm Oxytetracycline. Therefore, it can be said that the AC and VA are possible alternates of antibiotics.

Comparing the Change in SUVmax Over Time by the Type of Ductal Breast Carcinoma (유방암 환자 중 유관에서 발병되는 암의 종류(IDC와 DCIS)별 시간경과에 따른 SUVmax 변화에 대한 비교)

  • Hyoung, Mi-Jin;Kim, Jeong Nip;Moon, Pyeong Soo;Kim, Kil Hwan
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.140-144
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    • 2014
  • Purpose: The recent surge in breast carcinoma patients is reported in a variety of statistics. Breast cancer occurs mainly from duct and lobulus: 85% is from the breast ducts. The present study is aimed to distinguish the difference in $SUV_{max}$ changing over time by identifying the type of cancers attacking from the duct. Materials and Methods: The subjects of the study are 291 female breast cancer patients who have visited the present PET/CT center from July 1, 2012 to July 23, 2013. Based on the pathological results, 248 IDC (invasive ductal carcinoma) patients and 43 DCIS (ductal carcinoma in situ) patients were selected. In the same manner as the general PET/CT scan (3.7 MBq/Kg), F-FDG was injected, followed by the primary test (Routine tests) after 1 hr, and the secondary test (Delay test) after another hr. $SUV_{max}$ was measured after setting ROI in the lesion based on the data from the two tests. Results: As the comparative result of the change in the lesion $SUV_{max}$ between the two groups, IDC group's $SUV_{max}$ showed M=7.11 and SD=5.405 in the primary test and increased M=7.11 and SD=5.405 in the secondary test (P<0.05); DCIS group's $SUV_{max}$ showed M=2.739, SD=1.229 in the primary test and increased M=2.614, SD=1.470 in the secondary test (P<0.05). Conclusion: As the comparative result of $SUV_{max}$ over time between the groups, IDC showed increased $SUV_{max}$ in the secondary test (Delay test) compared to the primary test (Routine test) (P=0.000); DCIS showed decreased $SUV_{max}$ in the secondary test (Delay test) compared to the primary test (Routine test) (P=0.039). It was confirmed through this study that the change in $SUV_{max}$ has occurred over time by the type of breast cancer (IDC or DCIS) occurring from the breast ducts. However, the onset of breast cancers (ILC, LCIS) from the lobulus was not discussed due to the lack of samples. Future research on the breast cancers from the lobulus is suggested.

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