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Effect of Steam-Treated Zeolite BEA Catalyst in NH3-SCR Reaction (NH3-SCR 반응에서 스팀 처리된 zeolite BEA 촉매의 영향)

  • Park, Ji Hye;Cho, Gwang Hee;Hwang, Ra Hyun;Baek, Jeong Hun;Yi, Kwang Bok
    • Clean Technology
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    • v.26 no.2
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    • pp.145-150
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    • 2020
  • Nitrous oxide (N2O) is one of the six greenhouse gases, and it is essential to reduce N2O by showing a global warming potential (GWP) equivalent to 310 times that of carbon dioxide (CO2). Selective catalytic reduction (SCR) is a technology that converts ammonia into harmless N2 and H2O by using ammonia as a reducing agent to remove NOx, one of the air pollutants; the process also produces high denitrification efficiency. In this study, the Fe-BEA catalyst was steam-treated at 100 ℃ for 2 h before Fe ion exchange in the fixed bed reactor in order to investigate the effect of the steam-treated Fe-BEA catalyst on the NH3-SCR reaction. NH3-SCR reaction test of synthesized catalysts was performed at WHSV = 180 h-1, 370 to 400 ℃ in the fixed bed reactor. The Fe-BEA(100) catalyst steam-treated at 100 ℃ showed a somewhat higher activity than the Fe-BEA catalyst at 370 to 390 ℃. The catalysts were characterized by BET, ICP, NH3-TPD, H2-TPR, and 27Al MAS NMR in order to determine the cause affecting NH3-SCR activity. The H2-TPR result confirmed that the Fe-BEA(100) catalyst had a higher reduction of isolated Fe3+ than the Fe-BEA catalyst, and that the steam treatment increased the amount of isolated Fe3+ as an active species, thus increasing the activity.

Studies on the improvement of Nursery method for Late-seasonal Cultivation of Rice Varieties (Indica × Japonica) (통일계(統一系) 수도품종(水稻品種)의 만식재배(晩植栽培)를 위(爲)한 육모방법(育苗方法) 개선(改善)에 관(關)한 연구(硏究))

  • Choi, B.Y.;Jo, J.S.;Lee, J.C.
    • Korean Journal of Agricultural Science
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    • v.3 no.1
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    • pp.11-16
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    • 1976
  • This experiment was carried out to determine the most adequate type and period of nursery for the late seasonal cultivation of the new varieties of rice, Yusin and Josaengtongil. The results obtained are summarized as follows: 1. Semi-hot up-land nursery was much effective for the increase of the number of tillerings and the roots of rise seedlings compared with the semi-hot low-land nursery. The number of tillerings and roots was increased in 60 days seedlings compared with 50 or 60 days seedlings. 2. The abnormal heading has not appeared at the variety Yusin at all. The seedlings of Josaengtongil grown over 50 days at the semi-hot low-and nursery showed the abnormal heading, but the abnormal heading was not checked out at the seedlings of same variety grown for 60 days on the semi-hot upland nursery. 3. On the nursery not to cause the abnormal heading, earlier seeding was much effective for the hastening of the heading time and the hastening effect of heading time by earlier seeding was significantly greater at the variety Josaengtongil than Yusin 4. The number of ears per hill was significantly increased in the seedlings from the semi-hot up-land nursery compared with the semi-hot low-land nursery. 5. When the growing period of rice seedlings was not considered, the semi-hot up-land nursery resulted in higher yield of rice than the semi-hot low-land nursery. Considering the growing periods of rice seedlings, 40 days seedlings showed high yield at the semi-hot low-land nursery, however, at the semi-hot up-land nursery, 60 days seedlings showed higher yield of rice.

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Difference of Place Identity Perception and Landscape Preference between Residents and Tourists in Ihwa-dong Mural Village (이화동 벽화마을 주민과 관광객간의 장소 정체성 인식 및 경관 선호 차이에 관한 연구)

  • Kim, Yelim;Son, Yong-Hoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.1
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    • pp.105-116
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    • 2017
  • Murals in villages revitalize communities and spaces, and are economically efficient. Central and local governments are therefore actively undertaking Mural Village Projects but there are some issues and concerns about the projects for the provision of uniformed landscapes for the regions that are the result of a short-term completion of projects, and instead of cohesion, cause destruction of place identities. In addition, the problem of sustainable landscape management that is the result of low community involvement can be pointed out because the murals are products of government-led projects. The study covered the context of landscape and space change processes from a critical perspective, and focused on Ihwa-dong Mural Village, which is considered the first mural village in Korea and has begun to undergo drastic changes due to attention received from media. The purposes of this study are as follows. First, the study provides data about difference of place identity perception and landscape preference between residents and tourists in Ihwa-dong Mural Village. Second, this paper evaluates the current Mural Village Projects and finds alternative directions to improve the projects by using these data. This paper analyzed tourist hot spots in Ihwa-dong Mural Village by using SNS analysis, a field study and focus group interviews. The difference of place identity perception and landscape preference was examined among three groups: residents, new residents who are invited by Mural Village Projects, and tourists. This study showed that many tourists are focused on landscape areas that were not intentionally constructed projects. In addition, the locations of preferred landscapes and stores overlapped. Meanwhile, using qualitative data analysis, it was found that residents perceived the area as being an under-privileged location, while the murals, a non-daily landscape, largely affected place identity perception of new residents and tourists. For landscape preference, tourists preferred outdoor rest areas, while new residents and residents preferred less. Additionally, new residents and tourists preferred an area's night view while residents made no mention of this. Related to the direction of the projects, three groups showed their dependence on the government. This empirical study is significant from a participatory design perspective and in analyzing the issues for mural villages' landscapes, which are spreading across the nation and proceeding without criticism in urban regeneration. Implications for urban planners and suggestions for the future projects are given.

Study on the Distributional Characteristics and Classification of Quaternary Monogenetic Volcanoes in Jeju Island, Korea (제주도에 분포하는 제4기 단성화산체의 형태적 분류 및 분포 특성 연구)

  • Lee, Jeong-Hyun;Yun, Sung-Hyo
    • The Journal of the Petrological Society of Korea
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    • v.21 no.4
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    • pp.385-396
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    • 2012
  • Jeju island is the biggest volcanic island in Korea and there are over 455 Quaternary monogenetic volcanoes, of which approximately 373 volcanoes(82.0%) are cinder cones. Other volcanic forms in the island include sharp-pointed lava cone without crater(9 volcanoes; 2.0%), shield volcanoes(27 volcanoes; 5.9%), tuff rings(17 volcanoes; 3.7%), tuff cones(3 volcanoes; 0.7%), a maar(1 volcano; 0.2%) and lava domes(25 volcanoes; 5.5%). The monogenetic volcanoes include 15 small nested cinder cones(aloreum). The monogenetic volcanoes are more abundant in the eastern part of the island than in the western part. If the main cause of the weathering such as precipitation affected the shape of the monogenetic volcanoes, more monogenetic volcanoes(BC, CC, DC, etc.) are supposed to be present in the southern part that have more precipitation than in the northern part. But the distribution of the monogenetic volcanoes shows no difference between the southern and the northern parts. So we suggest that the difference of the climatic conditions did not affect the distribution or the shape of cinder cones. Tuff rings, tuff cones and a maar are distributed beneath the island or in the low-altitude areas along the shore although cinder cones are distributed in the interior of the island. This means that the volcanic activity which formed the monogenetic volcanoes resulted from either phreatomagmatic eruption or magmatic (hawaiian or strombolian) eruptions depending on the reaction with water (underground water or shallow waters). The distribution of the monogenetic volcanoes according to the altitude shows that 253(55.6%) volcanoes occur in low-lying coastal areas at an altitude below 300 m, 110(24.2%) in a middle mountainous area at an altitude between 300~600 m and 92(20.2%) in a high mountainous area at an altitude above 600 m. So more than half of monogenetic volcanoes are distributed in low-lying coastal areas.

Review on the Triassic Post-collisional Magmatism in the Qinling Collision Belt (친링 충돌대의 트라이아스기 충돌 후 화성작용에 대한 리뷰)

  • Oh, Chang Whan;Lee, Byung Choon;Yi, Sang-Bong;Zhang, Cheng Li
    • The Journal of the Petrological Society of Korea
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    • v.23 no.4
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    • pp.293-309
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    • 2014
  • The Qinling-Dabie-Sulu-Hongseong-Odesan collision belt was formed by the collision between the North China and South China Cratons during late Permian to Triassic. During the collision, Triassic post-collision igneous rocks regionally intruded in the Qinling and the Hongseong-Odesan collision belts which represent the western and eastern ends of the collision belt, respectively. However, no and minor Triassic post-collision igneous activities occur in the Dabie and Sulu belts respectively. The peak metamorphic pressure conditions along the Qinling-Dabie-Sulu-Hongseong-Odesan belt indicate that the slab break-off occurred at the depth of ultra-high pressure (UHP) metamorphic condition in the Dabie and Sulu belts and at the depths of high pressure (HP) or high pressure granulite (HPG) metamorphic condition in the Qinling and Hongseong-Odesan belts. In the Dabie and Sulu belts the heat supply from the asthenospheric mantle through the gab formed by slab break-off could not cause an extensive melting in the lower continental crust and lithospheric mantle directly below it due to the very deep depth of slab break-off. On the other hand, in the Qinling and Hongseong-Odesan belts, shallower slab break-off caused the emplacement of regional post collision igneous rocks. The post-collision igneous rocks occur in the area to the north of the Mianlu Suture zone in the western Qinling belt and crop out continuously eastwards into the areas to the north of the Shangdan Suture zone in the eastern Qinling belt through the areas within the South Qinling block. This distribution pattern of post collision igneous rocks suggests that the Triassic collision belt in the Mianleu Suture zone may be extended into the Shangdan Suture zone after passing through the South Qinling block instead into the boundary between the South Qinling block and the South China Craton.

Treatment of $Smilax$ $china$ L. Root Extract for Improvement of Storage Stability of $Mang-gae$ Rice Cake (망개떡의 저장성 향상을 위한 청미래덩굴 뿌리 추출물의 첨가)

  • Ko, Yu-Jin;Kim, Jin-Yong;Kim, Eun-Jung;Kim, Eun-Ja;Seol, Hui-Gyeong;Park, Geun-Hye;Chung, Gwon-Yong;Ryu, Chung-Ho
    • Food Science and Preservation
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    • v.19 no.2
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    • pp.167-172
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    • 2012
  • The antimicrobial activities of $Smilax$ $china$ L. against spoilage bacteria isolated from $Mang-gae$ rice cake were investigated and the storage stability of the $Mang-gae$ rice cake was enhanced. Spoilage bacteria, which cause $Mang-gae$ rice cake to rot, were isolated from commercial $Mang-gae$ rice cake, and most of the isolated strains were identified as $Bacillus$ sp. After the leaves, roots, shoots, and stalks of the $Smilax$ $china$ L. were extracted using 50% ethanol as the solvent, their antimicrobial activities were investigated using the paper disc method by treating them with 50 ${\mu}L$ of $Bacillus$ $cereus$, which is known as a major pathogenic micro-organism in foods that contain starch, as the test organism. The antimicrobial activities of the extracts were compared according to the size of the clear zones around the paper discs. The root extract showed significant antimicrobial activities. When red beans, which are used as stuffing for $Mang-gae$ rice cake, were treated with the root extract of the $Smilax$ $china$ L., the viable cell count of the $Mang-gae$ rice cake was 5.04 Log CFU/g after 48-hr storage, and the cake showed significantly slower growth of bacteria than with commercial products. These results show that treatment of red beans with $Smilax$ $china$ root extract could improve the storage stability of $Mang-gae$ rice cake.

Treatment Margin Assessment using Mega-Voltage Computed Tomography of a Tomotherapy Unit in the Radiotherapy of a Liver Tumor (간종양 방사선치료 시 토모테라피 메가볼트 CT를 이용한 치료 여백 평가)

  • You, Sei-Hwan;Seong, Jin-Sil;Lee, Ik-Jae;Koom, Woong-Sub;Jeon, Byeong-Chul
    • Radiation Oncology Journal
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    • v.26 no.4
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    • pp.280-288
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    • 2008
  • Purpose: To identify the inter-fractional shift pattern and to assess an adequate treatment margin in the radiotherapy of a liver tumor using mega-voltage computed tomography (MVCT) of a tomotherapy unit. Materials and Methods: Twenty-six patients were treated for liver tumors by tomotherapy from April 2006 to August 2007. The MVCT images of each patient were analyzed from the $1^{st}$ to the $10^{th}$ fraction for the assessment of the daily liver shift by four groups based on Couinard's proposal. Daily setup errors were corrected by bony landmarks as a prerequisite. Subsequently, the anterior-, posterior-, right-, and left shifts of the liver edges were measured by maximum linear discrepancies between the kilo-voltage computed tomography (KVCT) image and MVCT image. All data were set in the 2-dimensional right angle coordinate system of the transverse section of each patient's body. Results: The liver boundary shift had different patterns for each group. In group II (segment 2, 3, and 4), the anterior mean shift was $2.80{\pm}1.73\;mm$ outwards, while the left mean shift was $2.23{\pm}1.37\;mm$ inwards. In group IV (segment 7 and 8), the anterior-, posterior-, right-, and left mean shifts were $0.15{\pm}3.93\;mm$ inwards, $3.15{\pm}6.58\;mm$ inwards, $0.60{\pm}3.58\;mm$ inwards, and $4.50{\pm}5.35\;mm$ inwards, respectively. The reduced volume in group II after MVCT reassessment might be a consequence of stomach toxicity. Conclusion: Inter-fractional liver shifts of each group based on Couinard's proposal were somewhat systematic despite certain variations observed in each patient. The geometrical deformation of the liver by respiratory movement can cause shrinkage in the left margins of liver. We recommend a more sophisticated approach in free-breathing mode when irradiating the left lobe of liver in order to avoid stomach toxicity.

A Survey of Disease Occurrence in Korean Black Goats (흑염소 사육농가의 질병발생 실태조사)

  • Choe, Chang-Yong;Kang, Da-Won;Choi, Sun-Ho;Cho, Chang-Yeon;Jung, Byeong-Yeal;Son, Jun-Kyu;Ryu, Il-Sun;Hu, Tai-Young;Jung, Young-Hun;Kang, Seog-Jin;Do, Youn-Jeong;Kim, Ui-Hyung;Park, Yong-Sang;Son, Dong-Soo
    • Journal of Veterinary Clinics
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    • v.29 no.2
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    • pp.160-164
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    • 2012
  • The goat industry has been developing for many years in Korea to meet demands for food and medicine. However, many complicated patterns of disease have arisen in goat farms as this industry has developed. In this study, disease occurrence patterns in Korean black goats were surveyed in six professional farming households in Imsil and Soonchang in the Jeonbuk province and in Hamyang and Sachon in the Gyeongnam province to understand and extend the goat disease database. We observed morbidity rates between 2.0% and 9.8% for adult goats and between 2.9% and 68.3% for kids. Kids showed a markedly higher incidence of disease when compared to adults. The rate of disease occurrence was 40.0% for floppy kid syndrome (FKS), 37.7% for diarrhea, 16.0% for respiratory disease, and 1.9% for skin disease. The observed mortality rates were 0.7% ~ 10.0%, and 2.2% ~ 24.9% for adult goats and kids, respectively. In addition, FKS, diarrhea, and respiratory disease were observed in 38.3%, 28.9%, and 10.0%, respectively, of dead goats. In conclusion, the majority of diseases in goats occur during the neonatal period, and FKS is the highest single cause of mortality in Korean black goats. Thus careful attention must be paid to kids to reduce the goat mortality rate.

Cross-Reactivity and Digestive Enzyme Stability of Peach, Korean Cherry, and Hot Pepper (복숭아, 앵두, 고추의 교차반응성 및 소화효소안정성)

  • Kim, Eun-Jung;Ko, Yu-Jin;Lee, Gyeong-Ran;Seol, Hui-Gyeong;Kang, Chang-Min;Ryu, Chung-Ho
    • Journal of Life Science
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    • v.22 no.11
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    • pp.1487-1492
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    • 2012
  • Peach (Prunus persica) has been recognized as a food allergen for over 20 years. However, there is little information about cross-reactivity with other foods. The aim of this study was to research cross-reactivity of Korean cherry and hot pepper on patients allergic to peach and its stability by digestive enzyme treatment. Peach, Korean cherry, and hot pepper proteins were extracted and separated by Tricine-SDS-PAGE analysis. The protein extracts had a wide range of molecular weight, from 3 kDa to more than 26 kDa, and displayed different patterns of protein bands on Tricine-SDS-PAGE. Peach allergic patients' sera were used to detect the allergenic protein in three samples. Three peach allergic patients' sera reacted strongly with 9 kDa protein of peach, which was the expected lipid transfer protein (LTP) as the major allergen of peach and was detected with anti-LTP1 polyclonal antibody. However, the reactivity of the 23 kDa protein in Korean cherry and hot pepper protein was stronger than that of the 9 kDa protein. The stability of protein extracts on digestive enzyme treatment was examined using simulated gastric fluids (SGF) and simulated intestinal fluids (SIF), in which digestive enzyme stability is one of the characteristics of allergen potentially causing food allergy. Findings confirmed that allergenic proteins in peach, Korean cherry, and hot pepper were not completely digested by SGF and SIF treatments from results of SDS-PAGE analysis. These results confirmed that Korean cherry and hot pepper might cause cross-reactivity in peach allergic patients, and its allergenic proteins have stability against digestive enzymes.

Serological Investigation of the Infection Rate of Chlamydophila pneumonia among Residents of a Single University Dormitory (일개 대학 기숙사 거주 학생에 있어서 Chlamydophila pneumoniae의 혈청학적 감염률 조사)

  • Ryu, Jea Ki;Kim, Hyun-Kyung;Kim, Dong-Chan;Lee, Suk Jun
    • Journal of Life Science
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    • v.24 no.3
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    • pp.318-322
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    • 2014
  • Chlamydophila pneumonia is a common cause of community-acquired pneumonia throughout the world. It causes mild pneumonia or bronchitis in adolescents and young adults. Older adults may experience more severe disease and repeated infections. To the best of our knowledge, no study has attempted to investigate the prevalence of C. pneumonia in a closed community in Korea. We compared the infection rate of C. pneumonia among university dormitory residents using the miro-immunofluorescence (MIF) method. Antibody titers of IgG (1:32 or more) indicate past infection of C. pneumonia. A recent infection was defined as serum with a high titer of IgG (1:512 or more) or a positive IgM (1:16 or more). The past infection rate of C. pneumonia among the university dormitory residents was 71.7%. The recent infection rate of C. pneumonia according to IgG and IgM titers was 28.3% and 23.3%, respectively. The past infection positive rate according to the number of residence months was 1 month (50%), 7 months (71.4%), 13 months (66.7%), and 35 months (89.5%). The recent infection positive rate according to IgG antibody titers was 1 month (50%), 7 months (28.6%), 13 months (33.3%), and 35 months (10.5%). The recent infection rate of C. pneumonia according to IgM antibody titers was 1 month (41.7%), 7 months (28.6%), 13 months (26.7%), and 35 months (5.3%). The results suggest that the past infection rate of C. pneumonia is increased by the number of residence months in a closed community and that the recent infection rate of C. pneumonia according to IgG and IgM serological tests is decreased by the number of residence months.