• 제목/요약/키워드: Secondary sources

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A Review on Venom Enzymes Neutralizing Ability of Secondary Metabolites from Medicinal Plants

  • Singh, Pushpendra;Yasir, Mohammad;Hazarika, Risha;Sugunan, Sunisha;Shrivastava, Rahul
    • 대한약침학회지
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    • 제20권3호
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    • pp.173-178
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    • 2017
  • Objectives: Medicinal plants are vital sources of bioactive compounds that are useful for the treatment of patients with snake bites or are indirectly applicable for boosting the effects of conventional serum therapy. These plants are being used traditionally by local healers and tribes for the treatment of patients with snake bites and therefore can be used as an alternative against snake envenomation. Scientifically, using the secondary metabolites of plants to neutralize venom enzymes has an extra benefit of being based on traditional knowledge; also, the use of such metabolites for the treatment of patients with snake bites is cheaper and the treatment can be started sooner. Methods: All the available information on various secondary metabolites exhibiting venom neutralizing ability were collected via electronic search (using Google books, Pubmed, SciFinder, Scirus, Google Scholar, and Web of Science) and articles of peer-reviewed journals. Results:Recent interest in different plant has focused on isolating and identifying of different phytoconstituents that exhibit Phospholipase A2 activity and other venom enzyme neutralizing ability. In this support convincing evidence in experimental animal models are available. Conclusion: Secondary metabolites are naturally present, have no side effect, are stable for a long time, can be easily stored, and can neutralize a wide range of snake enzymes, such as phospholipase A2, hyaluronidase, protease, L-amino acid oxidase, 5'nucleotidase, etc. The current review presents a compilation of important plant secondary metabolites that are effective against snake venom due to enzyme neutralization.

현무암섬유를 이용한 LNG 화물창 2차 방벽의 기계적 특성에 대한 연구 (Effects of Basalt Fiber on the Mechanical Properties of Secondary Barrier for LNG Cargo Containment System)

  • 노우승;신해름;여승준;김만태
    • 한국산업융합학회 논문집
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    • 제27권1호
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    • pp.207-212
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    • 2024
  • Recently, with the strengthening of environmental regulations, there has been an increasing interest in eco-friendly energy sources, leading to a trend of the increasing scale of Cargo Containment Systems (CCS) for Liquefied Natural Gas (LNG) carriers. Among these systems, membrane tanks have gained popularity in LNG transport vessels due to their superior spatial utilization and competitiveness. However, due to high initial investment costs and the difficulty in repair in case of damage, a safety layer, the secondary barrier, must be installed without fail. In this study, in order to apply a new secondary barrier to the existing membrane-type LNG CCS, tests were conducted on the fiberglass layer previously used in the Triplex-Flexible Secondary Barrier (FSB), substituting it with basalt fiber. Tensile and vertical tensile tests were performed to assess the newly applied material. Environmental tests were conducted at room temperature (25℃) and extremely low temperatures (-170℃), considering the temperatures to which substances may be exposed during LNG vessel operations. The basalt-FSB produced in this study demonstrated superior results compared to the specifications of the existing product, confirming its potential applicability for implementation.

태양광전원 계통연계시험장치에 의한 수용가 전력품질특성에 관한 연구 (Analysis of Customer Power Quality Characteristics Using PV Test Devices)

  • 김병목;김병기;박재범;노대석
    • 한국융합학회논문지
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    • 제2권4호
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    • pp.21-27
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    • 2011
  • 현재 신 재생에너지 보급사업에 의해 설치되고 있는 태양광전원설비가 전력계통과 연계 운영될 경우 배전계통의 전력품질 요소에 어떠한 영향을 미치고 있는지를 모의시험을 통해 정확히 측정 분석하여 향후 분산형전원의 확대 보급에 따른 가이드라인의 구축과 기술적인 연계지침이 필요한 상황이다. 따라서 본 논문에서는 태양광이 연계되는 위치에 따른 선로임피던스($R{\pm}jX$)에 의하여 생기는 전압상승 및 하강에 의한 전력품질[Sag/Swell] 저하 현상에 대하여 태양광전원용 LabVIEW 프로그램을 통해 전력품질 시험을 수행하여 그 특성을 분석한다.

복합재료의 열-음향방출거동 (Thermo-Acoustic Emission Behavior of Composites)

  • 김영복;우성충;최낙삼
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2001년도 추계학술발표대회 논문집
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    • pp.111-115
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    • 2001
  • Thermo-acoustic emission (AE) from composite laminates under the repetitive thermal cyclic loads have been quantitatively analyzed in consideration of AE source mechanisms. The repetitive thermal load brought about a large reduction, i.e. an exponential decrease in AE total ringdown counts and AE amplitudes. It was thought that generation of thermo-AE during the first thermal cycle was not caused by crack propagation but by secondary microfracturing due to abrasive contact between crack surfaces.

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배우자선택과정에 관한 사적 고찰 (A Historical Review of Mate Selection Process)

  • 김혜선
    • 대한가정학회지
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    • 제31권2호
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    • pp.69-80
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    • 1993
  • This study intended to review the historical mate selection process and to present wholesome mate selection process. For this purpose, reviewing the contents of secondary sources and novel literature. The following conclusions were drawn from this study: Mate selection process was a kind of culture which was influenced by social atmosphere. And pre-17th century, most of the young people had social intercourse liberally. Therefore we must constitute wholesome mate selection culture through early socialization about heterosexual social intercourse.

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Biomass and secondary production of the three dominant amphipods (Crustacea) in a temperate sandy shore, southern Korea

  • Hwan, Yu-Ok;Rip, Seo-Hae
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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    • pp.435-436
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    • 2001
  • In sand beaches the benthic macrofauna feeding on primary food sources such as detritus and phytoplankton and being prey in turn for top predators such as fishes occupies a key position in the center of food chains. Amphipods are the most productive bentho-pelagic animals (Barnard, 1963) and are commonly consumed by fishes and larger crustaceans (Vetter, 1995). Consequently, amphipods play an important role in energy flow as a trophic link from primary producers to higher consumers(Chiaravalle et al., 1997).

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대기와 해양의 몇 개념들에 대한 중·고등학교 과학교사의 개념 (Conceptions of Secondary School Science Teachers on Some Concepts of Atmosphere and Ocean)

  • 국동식
    • 한국지구과학회지
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    • 제25권6호
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    • pp.402-408
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    • 2004
  • 이 연구의 목적은 중${\cdot}$고등학교 지구과학 전공 교들이 몇 가지 지구과학 개념에 대하여 가지고 있는 이해유형을 조사하는 것이다. 이 연구의 대상으로 선택한 개념은 저기압에서의 바람, 해류의 서안강화, 편서풍 파동, 온실효과, 오존층 그리고 대기압이며 중${\cdot}$고등학교 지구과학 전공교사 26명이다. 조사의 결과는 중${\cdot}$고등학교에서 교사들이 이들 개념을 학습지도할 때 필요하다고 생각되는 학습의 객관적 자료의 측면에서 분석하였고 그 결과는 다음과 같다. 지구과학 전공교사들도 이 연구에서 선정된 몇 가지 개념에 대하여 학생의 학습지도에 부족한 여러 가지 이해유형을 가지고 있으며 이들 유형 중에는 오개념들도 포함하고 있음을 알았다. 교사들은 저기압에서의 바람에 대하여 경도풍과 관련된 이해유형을, 서안강화에 대해서는 지구자전과 관련된 오개념을, 편서풍 파동에 대해서는 각운동량 보존과 관련된 오개념을, 온실효과에 대해서는 주된 온실기체와 관련된 오개념을, 오존층에 대해서는 지표부근의 오존기체 생성과 관련된 오개넘을, 그리고 대기압에 대해서는 대기압으로 인해 생기는 현상과 관련된 오개념을 가지고 있음을 발견하였다. 이 연구에서 발견된 교사의 여러 가지 이해유형은 지구과학개념의 힉습지도에서 유용하게 이용될 수 있을 것으로 생각한다.

소나무 잎 중 PBDEs의 조성, 발생원 및 지역적 농도 (Composition, Source, and Regional Concentration of PBDEs in Pine Needles)

  • 여현구;조기철;천만영
    • 대한환경공학회지
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    • 제28권8호
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    • pp.829-835
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    • 2006
  • PBDEs의 조성, 발생원 및 지역적 농도 분포를 확인하기 위해 국내의 여러지역(서울, 안성, 청주, 울산, 대구, 부산, 파도리)에서 자생하는 소나무 잎을 채취하였다. Hepta-BDE부터 deca-BDE까지의 동족체(homologs) 농도는 총 PBDEs의 농도와 매우 유의한 상관성(Pearson 상관계수 r>0.96, p<0.001)을 보였다. Deca-BDE는 다른 homologs에 비해 모든 시료에서 최대농도를 나타내었다. PBDE 함유 제품(Bromkal 70-5DE, DE-71)과 소나무 중 침착된 PBDE 동질체(congeners) 사이의 상관성이 높게 나타나 PBDE 함유 제품이 본 채취지점에서 발생원으로 평가되었다. 또한 BDE-47, -99, -100, -206, -207 및 -209는 모든 소나무 잎에서 주된 성분을 나타내었는데 이는 전세계적으로 다량 사용된 penta-BDE와 deca-BDE 함유 제품이 국내에도 다량으로 사용되었기 때문으로 판단된다. 그러나 BDE-209와 BDE-47, -99, -100간의 상관성은 유의하지 않았는데 이는 tetra-BDE와 penta-BDE는 대기-토양 분배와 같은 2차 발생원에 영향이 지배적인 반면 deca-BDE는 여전히 1차 발생원의 영향이 2차 발생원의 영향보다 지배적이었기 때문으로 판단된다.

Prismatic-core advanced high temperature reactor and thermal energy storage coupled system - A preliminary design

  • Alameri, Saeed A.;King, Jeffrey C.;Alkaabi, Ahmed K.;Addad, Yacine
    • Nuclear Engineering and Technology
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    • 제52권2호
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    • pp.248-257
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    • 2020
  • This study presents an initial design for a novel system consisting in a coupled nuclear reactor and a phase change material-based thermal energy storage (TES) component, which acts as a buffer and regulator of heat transfer between the primary and secondary loops. The goal of this concept is to enhance the capacity factor of nuclear power plants (NPPs) in the case of high integration of renewable energy sources into the electric grid. Hence, this system could support in elevating the economics of NPPs in current competitive markets, especially with subsidized solar and wind energy sources, and relatively low oil and gas prices. Furthermore, utilizing a prismatic-core advanced high temperature reactor (PAHTR) cooled by a molten salt with a high melting point, have the potential in increasing the system efficiency due to its high operating temperature, and providing the baseline requirements for coupling other process heat applications. The present research studies the neutronics and thermal hydraulics (TH) of the PAHTR as well as TH calculations for the TES which consists of 300 blocks with a total heat storage capacity of 150 MWd. SERPENT Monte Carlo and MCNP5 codes carried out the neutronics analysis of the PAHTR which is sized to have a 5-year refueling cycle and rated power of 300 MWth. The PAHTR has 10 metric tons of heavy metal with 19.75 wt% enriched UO2 TRISO fuel, a hot clean excess reactivity and shutdown margin of $33.70 and -$115.68; respectively, negative temperature feedback coefficients, and an axial flux peaking factor of 1.68. Star-CCM + code predicted the correct convective heat transfer coefficient variations for both the reactor and the storage. TH analysis results show that the flow in the primary loop (in the reactor and TES) remains in the developing mixed convection regime while it reaches a fully developed flow in the secondary loop.

정부간행물의 출판현황과 도서관의 정부간행물 운영실태분석 (An empirical analysis on the present situation of government publications and the operation of the publications in library)

  • 강미혜
    • 한국도서관정보학회지
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    • 제23권
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    • pp.79-108
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    • 1995
  • Government Publications are published to keep records of governmental activities and performances. In a rapidly changing information-oriented society, it is badly required for the operation system of government publications and a library to be effectively managed with government publications for satisfying 'right to know' of people and improving the obligation of government to 'let people know.' Accordingly, the purpose of this paper is to analyze such five research items as the situation of the publication and distribution of, government publications, the operation system of the publications in library, the number of publications regarding secondary information sources for the publications, and the legal deposit of the publications in the National Library, in order to proceed with a subject as to how much the government publication is satisfying 'right to know' of people. The research findings were suggested as follow : 1) Despite the fact that the publication of government publications has been gradually increased every year in numbers and kinds, it is unfortunately pointed out that the publications, distributions and sellings of them were not well organized and systematic. That is, the government publications had not been published more than 1.47% of all publications in number. Moreover, more than the half of the publications were non-periodically or annually published. To make the matter worse, it was not easy to get an access to the publications because of the publications not to be sold. 2) It a n.0, ppears that people could not use the publications efficiently because the library and administrative document office did not pay sufficient attention to public relations for all sorts of government publications. Not only that, there were not enough numbers of publications regarding such secondary information sources as bibliography, index and catalog. A speedy searching capacity for the information gave rise to another serious problem which the government publications could not be effectively used. 3) It is legally stated that all sorts of government publication should be deposited to the National Libraries. However, the law was not properly put into force because of lack of understanding of government agencies about the law.

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