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Cellulosic Ethanol Production (셀룰로식 (Cellulosic) 에탄올 생산)

  • Chung, Chang-Ho
    • KSBB Journal
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    • v.23 no.1
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    • pp.1-7
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    • 2008
  • The world demand of ethanol as an alternative fuel for gasoline is increasing rapidly because of high oil price and global climate change. Most of ethanol is currently produced from corn grain or sugars in sugarcane and sugar beet. Because these sources compete with foods and animal feed and are not expected to be enough for future demand of ethanol. Thus, cellulosic ethanol from agricultural residues or wood has to be commercialized in near future. Typical cellulosic ethanol production consists of pretreatment, enzyme hydrolysis, fermentation and product separation. This paper reviews the principles and status of each step and discusses issues for cellulosic ethanol production.

Analysis of Changes in Forest According to Urban Expansion Pattern and Morphological Features - Focused on Seoul and Daegu - (도시의 공간 확장 및 형태적 특징에 따른 산림녹지의 변화 분석 - 서울, 대구를 중심으로 -)

  • Ryu, Jieun;Hwang, Jinhoo;Lee, Junhee;Chung, Hye-In;Lee, Kyung-il;Choi, Yu-Young;Zhu, Yongyan;Sung, Min-Jun;Jang, Raeik;Sung, Hyun-Chan;Jeon, Seongwoo;Kang, Jin-Yung
    • Korean Journal of Remote Sensing
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    • v.33 no.5_3
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    • pp.835-854
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    • 2017
  • Government regulations and policies are important means of restraining the indiscreet expansion of urban areas. According to the standards from those means, it is clear that the fluctuation of forest green proportion encroached by the increase of urban space is obvious. In this study, we interpreted the changes of urban areas as well as the green ones owing to the urban expansion by the decades from 1996, with focusing on the cities of Seoul and Daegu highly developed in South Korea. The purpose of this study is to analyze the spatial expansion and morphological characteristics of urban land cover using not only satellite imageries (1996, 2006, 2016). but also the urban expansion intensity index (UEII) and GUIDOS program. Ultimately, this study is to compare the changes in the rate of forests due to urban expansions annually analyzed based on areas of forest elevation, slope, and the area of single forest patch. In Seoul, the expansion begun from urban space to suburban areas was comparatively rapid, which led the forest fragmentation and the gradual decline of the single patch. However, when it comes to DEM (Digital elevation model) and slope above a certain standard, by the development regulations, there was little decrease in area by anthropogenic developments. The city of Daegu has increased at a slow speed since 1996 in urban and suburban areas, whereas green forests have greatly increased through green forest conservation campaigns. In this way, as to the government policies and regulations, the quantitative and morphological expansion of cities owing to development could be controlled and forest spaces could be preserved as well. Therefore, regulations and policies by the government should be appropriately utilized for sustainable cities.

Morphological Properties of Binary Blends of Polyolefins Synthesized by Metallocene and Ziegler-Natta Catalysts (Ziegler-Natta와 메탈로센 촉매로 합성된 폴리올레핀 2원 블렌드의 상 형태학)

  • Kwag, Hanjin;Kim, Hak Lim;Choe, Soonja
    • Applied Chemistry for Engineering
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    • v.10 no.6
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    • pp.944-948
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    • 1999
  • The morphological properties of four binary blends of polyethylene synthesized by metallocene catalyst(MCPE) and four polyolefins prepared by Ziegler-Natta catalyst have been investigated to interpret the effect of micro-molecular structure on the phase morphology and interfacial behavior; four binary blend systems studied are high density polyethylene(HDPE)-metallocene polyethylene (MCPE), polypropylene(PP)-MCPE, poly(propylene-co-ethylene) (CoPP)-MCPE, and poly(propylene-co-ethylene-co-1-butylene) (TerPP)-MCPE, and they are all phase separated. The HDPE-MCPE blend shows evenly growing homogeneous HDPE domain on the continuous MCPE phase, on the other hand, the rest of three blends show complex heterogeneous phase behavior. The PP-MCPE blend shows that PP and MCPE and completely phase separated and phase inversion takes place at 50% MCPE. The CoPP-MCPE and TerPP-MCPE show enhanced interface due to the same micro-molecular structure of ethylene, and phase inversion takes place at 40% MCPE. In particular, TerPP-MCPE blend shows improved phase morphology between interfaces, and this may be arisen from the comonomer contents in TerPP, which are 1-butene and ethylene having the same chemical structure as that of MCPE. The enhancement of the phase morphology in the TerPP-MCPE blend is correlated with the mechanical and morphological properties. Thus, although the four blend systems are phase separated, the phase morphology suggests that the order of interfacial adhesion strength be HDPE-MCPE > TerPP-MCPE > CoPP-MCPE > PP-MCPE and that micro-molecular structure between constituents be one of major factors giving enhanced interfacial adhesion.

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Continuous Removal of Organic Matters of Eutrophic Lake Using Freshwater Bivalves: Inter-specific and Intra-specific Differences (CROM를 이용한 부영양 저수지의 유기물 제어: 이매패의 종 특이성에 대하여)

  • Lee, Ju-Hwan;Hwang, Soon-Jin;Park, Sen-Gu;Hwang, Su-Ok;Yu, Chun-Man;Kim, Baik-Ho
    • Korean Journal of Ecology and Environment
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    • v.42 no.3
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    • pp.350-363
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    • 2009
  • Inter- and intra-specific differences in removal activities, filtering rates (FR) and production of feces-and pseudo-feces (PF) between a native freshwater bivalve in Korea, Anodonta woodiana Lea and Unio douglasiae Griffith et Pidgeon, were compared using a continuous removal of organic matters (CROM) system. The CROM system comprised five steps; input of polluted water, control of water flow, mussel treatment, analysis of water quality and discharge of clean water. The study was designed to compare the removal activity of organic matters between A. woodiana and U. douglasiae, and the intra-specific differences between density and length in A. woordiana. Results clearly indicate that two kinds of mussels had obvious removal activities of seston in the eutrophic reservoir. First, if both are similar in shell length, there were no significant inter-specific differences in removal activity between A. woordiana and U. douglasiae (P>0.5), but FRs of U. douglasiae was relatively high due to low ash-fee dry weight. Second, if both are same in animal density, the smaller mussels (1$\sim$2 years old) showed a higher filtering rate and production of feces- and pseudo-feces and less release of ammonium than the larger mussels. Third, if both are same in biomass, FRs and PF of mussels were higher in the low-density tank than the high-density tank, While the Concentration of $NH_4$-N and $PO_4$-P released WRS similar to each other (P>0.5). Therefore, these results suggest that CROM system using a young bivalve A. woordiana can be applied to control the nuisance seston in eutrophic lake system, if a relevant species and density were selected. Additional pilot tests to optimize the age and density of domestic bivalves were needed for the generalization of CROM operation.

Crustal Characteristics and Structure of the Ulleung Basin, the East Sea (Japan Sea), Inferred from Seismic, Gravity and Magnetic Data (탄성파 및 중자력자료에 의한 울릉분지의 지각특성 및 구조 연구)

  • Huh, Sik;Kim, Han-Jun;Yoo, Hai-Soo;Park, Chan-Hong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.2
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    • pp.95-104
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    • 2000
  • Depths to four seismic sequence boundaries and the thickness of each sequence were estimated and mapped based on multi-channel seismic data in the Ulleung Basin. These depth-structure and isopach maps were incorporated into the interpretation of gravity and magnetic anomaly maps. The sediment thickness ranges from 3,000 m to 4,000 m in the central basin, while it reaches 6,000 m locally along the southwestern, western, and southeastern margins. The acoustic basement forms a northeast-southwest elongated depression deeper than 5000 m, and locally deepens up to 7,500 m in the southwestern and western margins. Low gravity anomalies along the western and southern margins are associated with basement depressions with thick sediment as well as the transitional crust between the continental and oceanic crusts. Higher gravity anomalies, dominant in the central Ulleung basin, broaden from southwest toward northeast, are likely due to the shallow mantle and a dense crust. A pair of magnetic elongations in the southeastern and northwestern margins appear to separate the central Ulleung basin from its margin. These magnetic elongations are largely dominated by intrusive or extrusive volcanics which occurred along the rifted margin of the Ulleung basin formed during the basin opening. The crust in the central Ulleung Basin, surrounded by the magnetic elongations, is possibly oceanic as inferred from the seismic velocity. The oceanic crust can be mapped in the central zone where it widens to 120 km from the southwest toward northeast. Bending of the crustal boundary in the southern part of the Ulleung Basin suggests that the Ulleung Basin has been deformed by a collision of the Phillipine plate into the Japan arc.

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Biological characteristics of Scuticociliate with a polymorphic life cycle of ciliate and cyst isolated from cultured olive flounder, Paralichthys olivaceus (양식넙치, Paralichthys olivaceus에서 분리된 Ciliate와 Cyst의 생활사를 갖는 스쿠티카섬모충의 생물학적 특성)

  • Jin, Chang-Nam;Kang, Hyun-Sil;Park, Geun-Tae;Lee, Je-Hee;Lee, Young-Don;Choi, Woo-Bong;Heo, Moon-Soo
    • Journal of fish pathology
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    • v.18 no.1
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    • pp.19-28
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    • 2005
  • Scuticociliatosis has badly settled one of most damaging diseases during the seedling production process of olive flounder. Paralichthys olivaceus in Korea. We isolated a new type of Scuticociliate from flounder. The parasite metamorphoses to ciliate and cyst phases with each other by environmental changes and survive for a relatively long span. The ciliate was measured average 41.8 ${\mu}m$ in length and 21.0 ${\mu}m$ in width, and cyst was 17.0 ${\mu}m$ and 13.5 ${\mu}m$, respectively. Nutritional condition was determined as a major parameter of metamorphosing between ciliate and cyst stages. The ciliate transforms to a cyst stage because of food shortage, and the cyst returns to a ciliate stage with a favorite environmental condition and shows active growth and reproduction. The ciliate multiplied at the maximal density of $2.9 {\times} 10^5 {m\ell}^{-1}$cells in vitro cultivation at $15 ^{\circ}C$temperature using MS BHI medium and bacterial food sources. The ciliate could be proliferated at a 2.5 to $30 ^ \circ}C$ temperature range, pH 6 to 9, and 1 to 55 ppt salinity. Particularly, it survived over one week at $0 ^{\circ}C$temperature showing a high resistance against unfavorable environmental conditions. And the cyst survived for 320 days in the condition of $5 ^{\circ}C$with no feeding, but its survival period was markedly shortened in higher temperature conditions. The chemotherapeutants (formalin and hydrogen peroxide) were clarified as effective chemicals against the ciliate during in vitro trials, but the effect of therapeutants differed in proportion, depending upon the density and the bathing time of chemical compounds.

Comparison of Breeding Value by Establishment of Genomic Relationship Matrix in Pure Landrace Population (유전체 관계행렬 구성에 따른 Landrace 순종돈의 육종가 비교)

  • Lee, Joon-Ho;Cho, Kwang-Hyun;Cho, Chung-Il;Park, Kyung-Do;Lee, Deuk Hwan
    • Journal of Animal Science and Technology
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    • v.55 no.3
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    • pp.165-171
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    • 2013
  • Genomic relationship matrix (GRM) was constructed using whole genome SNP markers of swine and genomic breeding value was estimated by substitution of the numerator relationship matrix (NRM) based on pedigree information to GRM. Genotypes of 40,706 SNP markers from 448 pure Landrace pigs were used in this study and five kinds of GRM construction methods, G05, GMF, GOF, $GOF^*$ and GN, were compared with each other and with NRM. Coefficients of GOF considering each of observed allele frequencies showed the lowest deviation with coefficients of NRM and as coefficients of GMF considering the average minor allele frequency showed huge deviation from coefficients of NRM, movement of mean was expected by methods of allele frequency consideration. All GRM construction methods, except for $GOF^*$, showed normally distributed Mendelian sampling. As the result of breeding value (BV) estimation for days to 90 kg (D90KG) and average back-fat thickness (ABF) using NRM and GRM, correlation between BV of NRM and GRM was the highest by GOF and as genetic variance was overestimated by $GOF^*$, it was confirmed that scale of GRM is closely related with estimation of genetic variance. With the same amount of phenotype information, accuracy of BV based on genomic information was higher than BV based on pedigree information and these symptoms were more obvious for ABF then D90KG. Genetic evaluation of animal using relationship matrix by genomic information could be useful when there is lack of phenotype or relationship and prediction of BV for young animals without phenotype.

Surface Exchange of Energy and Carbon Dioxide between the Atmosphere and a Farmland in Haenam, Korea (한국 해남 농경지와 대기간의 에너지와 이산화탄소의 지표 교환)

  • Hee Choon Lee;Jinkyu Hong;Chun-Ho Cho;Byoung-Cheol Choi;Sung-Nam Oh;Joon Kim
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.5 no.2
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    • pp.61-69
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    • 2003
  • Surface energy and $CO_2$ fluxes have been measured over a farmland in Haenam, Korea since July 2002. Eddy covariance technique, which is the only direct flux measurement method, was employed to quantitatively understand the interaction between the farmland ecosystem and the atmospheric boundary layer. Maintenance of eddy covariance system was the main concern during the early stage of measurement to minimize gaps and uncertainties in the dataset. Half-hourly averaged $CO_2$ concentration showed distinct diurnal and seasonal variations, which were closely related to changes in net ecosystem exchange (NEE) of $CO_2$. Daytime maximum $CO_2$ uptake was about -1.0 mg $CO_2$ m$^{-2}$ s$^{-1}$ in August whereas nighttime $CO_2$ release was up to 0.3 mg $CO_2$ m$^{-2}$ s$^{-1}$ during the summer. Both daytime $CO_2$ uptake and nighttime release decreased gradually with season. During the winter season, NEE was from near zero to 0.05 mg $CO_2$ m$^{-2}$ s$^{-1}$ . FK site was a moderate sink of atmospheric $CO_2$ until September with daily NEE of 22 g $CO_2$ m$^{-2}$ d$^{-1}$ . In October, it became a weak source of $CO_2$ with an emission rate of 2 g $CO_2$ m$^{-2}$ d$^{-1}$ . Long-term flux measurements will continue at FK site to further investigate inter-annual variability in NEE. to better understand these exchange mechanism and in-depth analysis, process-level field experiments and intensive short-term intercomparisons are also expected to be followed.

Relationship between HsCRP and Pulse Transit Time (HsCRP와 맥파전달시간에 대한 연구)

  • Kim, Yun-Jin;Min, Hong-Gi;Kim, Young-Joo;Jeon, Ah-Young;Jeon, Gye-Rok;Ye, Soo-Young
    • Journal of Life Science
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    • v.17 no.2 s.82
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    • pp.218-222
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    • 2007
  • The purpose of this study is to evaluate the relationship between high sensitive C-reactive protein (hsCRP) and pulse transit time (PPT). Apparently healthy 233 subjects had been enrolled in the health promotion center of the Pusan National University Hospital from Jan. 29 to Feb. 26, 2004. They had no previous history of diabetes, hypertension and hyperlipidemia. Subjects were categorized according to tertiles of hsCRP level [Group 1: first tertile $(0.01\;{\sim}\;0.02\;mg/dl)$, Group 2: second tertile $(0.03\;{\sim}\;0.05\;mg/dl)$, Group 3: third tertile $(0.06\;{\sim}\;0.12\;mg/dl)$, and Group 4: Fourth tertile $(0.13\;{\sim}\;16.8\;mg/dl)$]. PTT body mass index (BMI), total cholesterol (T-C), LDL-cholesterol(LDL-C), blood sugar (BS), systolic blood pressure (sBP) and diastolic blood pressure (dBP) were significantly different among hsCRP groups (p<0.05). HsCRP is positively related with BMI, tryglyceride (TG), LDL, sBP and dBP (p<0.05), and negatively related with PTT and HDL-cholesterol (HDL-C) (p<0.05). PTT is significantly negatively related with hsCRP, T-C, TG, LDL-C, BS, dBP and sBP (p<0.05). The hsCRP and PTT were related before controlling BMI, T-C, LDL-C, sBP, and dBP, but not related after conkolling. The relationship between hsCRP and PTT depends on cardiovascular disease risk factors.

Effect of Fermented Cirsium japonicum Extract on Testosterone Deficiency Syndrome (엉겅퀴 발효 추출물을 통한 남성 갱년기 증상 개선 효과)

  • Jeong, Byung Seo;Kim, Seong Hoon;Kim, Hyun Pyo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.7
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    • pp.790-800
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    • 2017
  • As men get older, total testosterone levels decline gradually, and concentrations of free and bioavailable testosterone decline sharply with each decade beyond their 30s. Andropause or testosterone deficiency syndrome (TDS) is defined as a decrease in sexual satisfaction or decline in general well-being accompanied by low levels of testosterone in older men. This male climacteric is characterized by nervousness, reduced potency, decreased libido, irritability, fatigue, depression, memory problems, sleep disturbances, and hot flushes. Cirsium japonicum (CJ) is used as a traditional medicine for hemorrhage, blood congestion, and inflammation in Korea. However, there is no report on the efficacy of CJ treatment for TDS. In this study, we observed the mitigating effect of CJ extract (CE) and fermented CJ extract (FCE) on symptoms of TDS. In elderly male rats, total and testosterone levels, hind limbs muscles, forced swimming time, and total and motile sperm counts significantly increased after daily intake of CE and FCE for 6 weeks. In contrast, sex hormone binding globulin, retroperitoneal fat, total serum cholesterol, and triglyceride levels were significantly reduced in CE and FCE groups. However, there was no difference in prostate specific antigen, aspartate aminotransferase, and alanine aminotransferase levels among all groups, which means CE and FCE did not have putative adverse effects. In a cell experiment, we also observed that CE and FCE enhanced expression of genes related to testosterone biosynthesis but reduced genes involved in testosterone conversion. On the whole, these positive effects on TDS were greater in FCE compared to CE. Thus, these results suggest the potential of FCE as a promising natural product for recovering testosterone levels and alleviating TDS.