• Title/Summary/Keyword: Yi Yi

Search Result 15,095, Processing Time 0.051 seconds

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
    • /
    • v.26 no.2
    • /
    • pp.145-150
    • /
    • 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.

A Study on the Adsorption and Desorption Characteristics of Metal-Impregnated Activated Carbons with Metal Precursors for the Regeneration and Concentration of Ammonia (암모니아의 재생 및 농축을 위한 금속 전구체에 따른 금속 첨착 활성탄의 흡착 및 탈착 특성에 관한 연구)

  • Cho, Gwang Hee;Park, Ji Hye;Rasheed, Haroon Ur;Yoon, Hyung Chul;Yi, Kwang Bok
    • Clean Technology
    • /
    • v.26 no.2
    • /
    • pp.137-144
    • /
    • 2020
  • Metal-impregnated activated carbons were prepared via ultrasonic-assisted impregnation method for regeneration and low ammonia concentration. Magnesium and copper were selected as metals, while chloride (Cl-) and nitrate (NO3-) precursors were used to impregnate the surface of activated carbon. The physical and chemical properties of the prepared adsorbents were characterized by TGA, BET, and NH3-TPD. The ammonia breakthrough test was carried out using a fixed bed and flowing ammonia gas (1000 mg L-1 NH3, balanced N2) at 100 mL min-1, under conditions of temperature swing adsorption (TSA) and pressure swing adsorption (PSA, 0.3, 0.5, 0.7, 0.9 Mpa). The adsorption and desorption performance of ammonia were in the order of AC-Mg(Cl) > AC-Cu(Cl) > AC-Mg(N) > AC-Cu(N) > AC through NH3-TPD and TSA and PSA processes. AC-Mg(Cl) using MgCl2 showed the average adsorption amount of 2.138 mmol/g at TSA process. Also, AC-Mg(Cl) showed the highest initial adsorption amount of 3.848 mmol/g at PSA 0.9 Mpa. When metal impregnated the surface of the activated carbon, it was confirmed that not only physical adsorption, but also chemical adsorption increased, making enhancement in adsorption and desorption performances possible. Also, the prepared adsorbents showed stable adsorption and desorption performances despite repeated processes, confirming their applicability in the TSA and PSA processes.

Single Nucleotide Polymorphisms (SNPs) Discovery in GHSR Gene and Their Association Analysis with Economic Traits in Korean Native Chickens (GHSR 유전자 내 유전변이의 탐색과 한국재래계의 성장 및 산란 특성에 미치는 연관성 분석)

  • Choi, So-Young;Hong, Min-Wook;Yang, Song-Yi;Kim, Chong-Dae;Jeong, Dong Kee;Hong, Yeong Ho;Lee, Sung-Jin
    • Korean Journal of Poultry Science
    • /
    • v.43 no.4
    • /
    • pp.273-279
    • /
    • 2016
  • Recently, it was reported that certain polymorphisms in the growth hormone secretagogue receptor gene (GHSR) are associated with the growth of chickens. However, the correlation between GHSR polymorphisms and economic traits has not been investigated in Korean native chickens (KNCs). Therefore, the objective of this study was to confirm the suitability of the GHSR gene as a candidate for genomic selection and identify a genetic marker for KNCs. A total of 220 KNCs from six breeds raised at the National Institute of Animal Science were genotyped for the c.739+726 SNP in the GHSR gene using polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP), and the sequence for a subset of 30 birds was analyzed using direct sequencing. The association between the SNP genotypes and the economic traits of the KNCs was analyzed using the statistical package for the social science (SPSS) software program. The association analysis between the c.739+726T>C SNP and economic traits revealed that the SNP was significantly associated with body weight at 150 and 270 days (BW150 and BW270, respectively) in all KNCs (p<0.01), BW150 in KNC (Gary) (p<0.05), and egg production number in KNC (White, p<0.05). In addition, the SNPs discovered using direct sequencing (513A>G, 517A>T) had a significant effect on the body weight and egg production traits (p<0.05). In conclusion, these results might be useful as a basis for studies on the improvement of KNC breeds. Furthermore, these results suggest that the SNPs (c.739+726T>C, 513A>G, and 517A>T) located in the GHSR gene could be useful molecular genetic markers for KNCs.

Freshness Comparison of Lettuce (Lactuca sativa L.) in accordance with Storage and Packaging Method on High-temperature Period (결구상추 고온기 포장 및 저장방법에 따른 신선도 비교)

  • Bark, Doe-Ey;Yoon, Yi-Na;Woo, Ye Jinn;Cheung, Gum Hang;Hwang, Sae Bom;Park, SuHyoung;Woo, Young-June;Shin, Chul;Choi, Dong-soo;Lim, Junhyung;Park, See Eun;Lee, Jung-Soo
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.21 no.1
    • /
    • pp.35-40
    • /
    • 2015
  • Effect of packaging and storage methods for enhancing the shelf life and improving the postharvest quality of lettuce (Lactuca sativa L.) was studied during high temperature period. Lettuces were packed using four packaging and storage types: (A) plastic box container (control); (B) plastic box container covered with high density polyethylene (HDPE) film; (C) plastic box container with lettuce wrapped in linear low-density polyethylene (LLD-PE) film; and (D) plastic box container with lettuce with its stem. The quality parameters, such as fresh weight loss, SPAD value, and appearance of lettuce were investigated. The lettuce wrapped with LLD-PE film inside the plastic box container showed the lowest weight loss, highest SPAD value and best appearance compared to those exposed to the other packaging and storage methods during the three-week storage at $2^{\circ}C$. The results indicate that the marketability of lettuce can be optimized if proper packaging and storing is adopted. Prolonging the freshness even on low temperature storage will increase the potential of its sale ability in the domestic market even during summer season.

  • PDF

Areal Distribution Ratios of Constituent Rocks with Geologic Ages and Rock Types by GIS in the Gyeongsangbug-Do and Daegu Areas (GIS에 의한 경북-대구지역 구성암류의 지질시대별 및 암종별 분포율)

  • Yun, Hyun-Soo;Lee, Jin-Young;Yang, Dong-Yoon;Hong, Sei-Sun;Kim, Ju-Yong;Yi, Sang-Heon
    • The Journal of the Petrological Society of Korea
    • /
    • v.19 no.1
    • /
    • pp.1-18
    • /
    • 2010
  • On the ArcGIS 9.2 program in Gyeongsangbug-Do and Daegu areas, distribution ratios of rock types and geologic ages were obtained from the 1 : 250,000 scaled digital geologic and geomorphic maps. The obtained distribution ratios here will be used the geologic information data for industrialization and development planning of rock resources. The Gyeongsangbug-Do area consists of 86 rock types that can be divided into 10 large groups in geologic age. Their geologic distribution ratios show the decreasing in the order of Cretaceous, Precambrian, Jurassic, Quaternary, Age-unknown and Tertiary, all of which occupy the prevailing ratio of 96.30% in the area. Of which, sixteen rock types are somewhat dominant ones (64.04%). They are of Precambrian Yulri group and granite gneiss of the Yeongnam metamorphic complex and biotite gneiss of the Sobaegsan metamorphic complex, Age-unknown granite, Jurassic granite, Cretaceous Gasongdong and Dogyedong formations of the Yeongyang sub-basin, Nagdong and Chunsan formations and intermediate-basic volcanics of Euiseong sub-basin, Jinju and Jindong formations and andesite-andesitic tuff of Milyang sub-basin, and hornblende granite, and Quaternary alluvium. They show relatively narrow ranges of 2.07-6.53% in geologic distribution in exception of Jurassic granite showing 13.14%. And the rest 70 rock types appear to very narrow range between 0.01 and 1.94 %. On the other hand, twelve rock types are developed in the Daegu area. Their geologic ages appear to be classified into Cretaceous and Quaternary occupying 86.05% and 11.39%, respectively. Seven rock types take possession of 94.04% among the all rocks. The major rock types are Jinju formation of the Sindong group, Chilgog, Haman and Jindong formations of the Hayang group, andesite and andesitic tuff, hornblende granite and Quaternary alluvium. With exception of andesite and andesitic tuff of 37.40%, the types show slightly wide range of 3.25-17.39%, which apparently differ trends from that of Gyeongsangbug-Do area. And the rest of rock types have narrow ranges of 0.22-1.81% in the Daegu area.

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
    • /
    • v.23 no.4
    • /
    • pp.293-309
    • /
    • 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.

Acetic acid fermentation properties and antioxidant activity of lemongrass vinegar (레몬그라스 식초의 초산발효 특성과 항산화 활성)

  • Yi, Mi-Ran;Kang, Chang-Hee;Bu, Hee-Jung
    • Food Science and Preservation
    • /
    • v.24 no.5
    • /
    • pp.680-687
    • /
    • 2017
  • This study investigated acetic acid fermentation properties and antioxidant activity of vinegar by addition of lemon grass to develop high quality vinegar by using lemongreass. Traditional brown rice wine contained 5% lemongrass powder and had an alcohol content of 7.2%. The wine was fermented by Acetobacter. sp. RIC-V and made into lemongrass vinegar (LV). The pH and total acidity of the LV were 3.13% and 7.21%, respectively. Fructose was detected whereas glucose, sucrose, and maltose were not detected. Among organic acids, acetic acid was highest at 3658.6 mg%; trace amounts of lactic acid, citric acid, malic acid, tartaric acid, and oxalic aicd were detected. Of the 17 free amino acids, glutamic acid, histidine, alanine, and proline were mainly detected. To conduct total polyphenol content and ABTS radical scavenging activity, 3% and 5% lemongrass powder (P3LV, P5LV) and 1%, 2%, and 3% of lemongrass extract (E1LV, E2LV, E3LV) were added to LV, respectively. Total phenolics increased as the added lemongrass powder and extract increased. Total phenolics were 490.9, 559.4, and $895.7{\mu}g$ gallic acid equivalents/mL in brown rice vinegar, LV, P5LV. ABTS radical scavenging activities were 43.2%, 58.0%, and 91.0% in brown rice vinegar, LV, P5LV, respectively. These results show that lemongrass vinegar has considerable potential as a high quality functional vinegar with antioxidative effects.

Disinfection of Fusarium-infected Rice Seeds by Prochloraz and Gaseous Chlorine Dioxide

  • Jeon, Young-ah;Lee, Young-yi;Lee, Ho-sun;Sung, Jung-sook;Lee, Seokyoung
    • 한국균학회소식:학술대회논문집
    • /
    • 2014.10a
    • /
    • pp.25-25
    • /
    • 2014
  • Three species of Fusarium, F. fujikuroi, F. verticillioides and F. proliferatum, are known to be associated with bakanae disease of rice [1, 2]. F. fujikuroi infects rice flowers and survive in endosperm and embryo of the seeds. Infected seed is an important source of primary inoculum of pathogens [3]. Seeds of rice (Oryza sativa cv. Boramchan) collected from bakanae-infected field were found to be 96% infected with Fusarium sp., 52% with F. fujikuroi, 42% with F. verticillioides, and 12% with F. proliferatum as determined by incubation method and species-specific PCR assays. F. fujikuroi was detected at lemma/palea, endosperm and embryo whereas F. verticillioides and F. proliferatum were recovered only from lemma/palea by means of component plating test. Seed disinfection methods have been developed to control bakanae disease and prochloraz has been most widely used for rice seeds. Two chemicals formulated with prochloraz (PC 1) and prochloraz + hexaconazole (PC 2) that inhibit biosynthesis of ergosterol strongly reduced the incidence of Fusarium spp. on selective media to 4.7% and 2.0%, respectively. Disease symptoms of rice seedlings in nursery soil were alleviated by chemical treatment; seedlings with elongated leaves or wide angle between leaf and stem were strikingly reduced from 15.6 to 3.2% (PC 1) and 0 (PC 2), stem rots were reduced from 56.9 to 26.2% (PC 1) and 32.1% (PC 2), and normal seedling increased from 0.4 to 13.3% (PC 2). Prochloraz has some disadvantages and risks such as the occurrence of tolerant pathogens [4] and effects on the sterol synthesis in animals and humans [5]. For these reasons, it is necessary to develop new disinfection method that do not induce fungal tolerance and are safe to humans and animals. Chlorine dioxide ($ClO_2$), that is less toxic, produces no harmful byproducts, and has high oxidizing power, has been reported to be effective at disinfection of several phytopathogenic fungi including Colletotrichum spp. and Alternaria spp. [6]. Gaseous $ClO_2$ applied to rice seeds at a concentration of 20 ppm strongly suppressed mycelial growth of Fusarium fujikuroi, F. verticillioides and F. proliferatum. The incidence of Fusarium spp. in dry seed with 8.7% seed moisture content (SMC) tended to decrease as the concentration of $ClO_2$ increased from 20 to 40 ppm. Applying 40 ppm $ClO_2$ at 90% relative humidity, incidence was reduced to 5.3% and resulted in significant reduction of disease symptoms on MS media. In nursery soil, stem rot was reduced from 56.9 to 15.4% and the number of normal seedlings increased from 0.4 to 25.5%. With water-soaked seeds (33.1% SMC) holding moisture in the endosperm and embryo, the effectiveness of disinfection using $ClO_2$ increased, even when treated with only 20 ppm for four hours. This suggests that moisture was a key element for action of $ClO_2$. Removal of the palea and lemma from seeds significantly decreased the incidence of Fusarium spp. to 3.0%. Seed germination appeared to decrease slightly by water-soaking at $30^{\circ}C$ because of increased SMC and by physical damage of embryos from hulling. These results indicate that the use of gaseous $ClO_2$ was effective as a means to disinfect rice seeds infected with Fusarium spp. and that moisture around the pathogens in the seed was an important factor for the action of $ClO_2$. Further investigations should be conducted to ascertain the best conditions for complete disinfection of Fusarium spp. that infect deep site of rice seeds.

  • PDF

Research on the current conditions of cultural heritage management in North Korea - an example of the management of provincial sites - (북한의 문화유산 관리 현황 연구 - 지방의 유적 관리 사례를 중심으로 -)

  • Kim, Hyunwoo;Yi, Seonbok
    • Korean Journal of Heritage: History & Science
    • /
    • v.52 no.4
    • /
    • pp.4-17
    • /
    • 2019
  • Both as a means of improving North-South relations, as well as a necessary component for carrying out research on the past of the Korean peninsula, interest in North Korean cultural resources has been growing in South Korean society. As a result, studies have begun to look beyond North Korean cultural resources themselves and attempt to determine how cultural resources are managed in North Korea. Such studies have tended to investigate laws related to the management of cultural heritage in North Korea, but information gleaned from laws alone is limited. To provide a more complete picture, research must also investigate how cultural resource management laws are applied and enforced and also take into consideration aspects of cultural resource management that are not directed or regulated by law. In this study, we refer to the current National Cultural Resources Protection Laws in order to investigate systems of cultural resource management in North Korea. Furthermore, we conducted interviews with a former North Korean national who had until recently worked as a director of historical sites in North Korea. Through comparisons of information relating to organization, labor power, responsibilities, budget, and other factors of cultural resource management gained through the interviews and the 'National Cultural Resources Protection Laws,' we hoped to gain a fuller understanding of the reality of cultural resource management in North Korea. As a result, we were able to gain a better understanding of the organization and tasks related to cultural resource management and, at the same time, clarify some of the provisions that were unclear in the laws. Throughout the process, we were also able to determine that the management of cultural resources in North Korea is currently inadequate. However, because this study focuses on a specific region and is limited only to historical sites, it is difficult to generalize our findings to the entirety of cultural resource management in North Korea. In order to gain an objective and more accurate understanding of the current state of cultural resource management in North Korea, information must be collected at many levels to be synthesized and compared.

A Study on Personal Diaries in the Joseon Period (조선시대 개인 일기의 현황과 특징)

  • Lee, Jong-suk
    • Korean Journal of Heritage: History & Science
    • /
    • v.52 no.4
    • /
    • pp.142-153
    • /
    • 2019
  • The Joseon Dynasty (1392-1910) left behind a wealth of documentary heritage, including collections of literary works, personal letters, and journals, as well as public documents such as Veritable Records of the Joseon Dynasty (Joseon Wangjo Sillok), Diaries of the Royal Secretariat (Seungjeongwon Ilgi), and State Protocols (Uigwe). Such heritage also includes personal diaries that have been highly regarded for their frank and vivid records of people's lives in the Joseon period. There have been great diaries published and intended for reading by the Korean public, including War Diaries (Nanjung Ilgi, 1592~1598) by Yi Sun-sin and Diaries of Jehol (Yeolha Ilgi, 1780) by Park Ji-won. Unfortunately, a great majority of these personal records remain unknown to the world. Such great records have not been given an opportunity to be documented properly, but are left outside public attention, abandoned to be damaged and destroyed. Few personal diaries of the Joseon period were written on good-quality paper. After the death of their authors, these diaries were left to be kept by their descendants; this explains why many of these records have been in poor condition, particularly when compared with the public records published by the government of Joseon, such as Sillok and Uigwe, even when these were lucky enough to be taken care of by the authors' descendants. Even after surviving a long time, many of these personal records remain in the form of manuscripts, written in semi-cursive and cursive scripts of Chinese characters, thus making it even more difficult for the people of the current generation -- most of whom have not been given an opportunity to learn Chinese characters at school -- to take care of their documentary heritage properly. Meanwhile, it is also true that, as the value of the public records published by the government of Joseon as historical materials has grown, they are used more often as content for TV dramas such as Daejanggeum. At the same time, there have been increasingly louder voices citing the need for the study, preservation, and management of the personal diaries from Joseon. Considering the situation, this study provides a general overview of the personal diaries of Joseon as recently surveyed by the National Research Institute of Cultural Heritage, as well as their characteristic features, subjects, and backgrounds. This study is expected to contribute to future research on the preservation and management of the personal diaries of Joseon.