• Title/Summary/Keyword: 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
    • Journal of Pharmacopuncture
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    • v.20 no.3
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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.

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

  • Woo-Seung Noh;Hae-Reum Shin;Seung-June Yeo;Man-Tae Kim
    • Journal of the Korean Society of Industry Convergence
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    • v.27 no.1
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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.

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

  • Kim, Byungmok;Kim, Byungki;Park, Jeabum;Rho, Daeseok
    • Journal of the Korea Convergence Society
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    • v.2 no.4
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    • pp.21-27
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    • 2011
  • Recently, new distributed power sources such as photovoltaic, wind power, fuel cell systems etc. are energetically interconnected and operated in the distribution feeders, as one of the national projects for alternative energy. When new power sources are considered to be interconnected to distribution systems, bi-directional power flow and interconnection conditions of new power sources may cause several power quality problems like voltage sag, voltage swell, harmonics, since new power sources can change typical characteristics of distribution systems. Under these situations, this paper deals with the analysis the power quality problems at primary and secondary feeders in distribution systems, when new power sources like photovoltaic (PV) systems are interconnected, by using the test devices for PV systems based on the LabVIEW S/W. This paper presents the test device which is consisted with model distribution system and model PV systems. By performing the simulation for power quality operation characteristic based on the test facilities, this paper presents the optimal countermeasures for power quality.

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

  • 김영복;우성충;최낙삼
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2001.10a
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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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A Historical Review of Mate Selection Process (배우자선택과정에 관한 사적 고찰)

  • 김혜선
    • Journal of the Korean Home Economics Association
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    • v.31 no.2
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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
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.05a
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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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Conceptions of Secondary School Science Teachers on Some Concepts of Atmosphere and Ocean (대기와 해양의 몇 개념들에 대한 중·고등학교 과학교사의 개념)

  • Kook, Dong-Sik
    • Journal of the Korean earth science society
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    • v.25 no.6
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    • pp.402-408
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    • 2004
  • The purpose of this study is to investigate various conceptions of secondary school earth science teachers on some concepts in secondary school earth science courses; wind in cyclone, western intensification of ocean current, westerly wave, greenhouse effect, ozone layer and atmospheric pressure. The subject is 26 in-service teachers of earth science teachers. The results were analyzed on the view of teaching sources for earth science teachers. The results show that earth science teachers have also various misconceptions on some concepts selected in this study. A number of partial understandings were found that were not enough to apply to teaching concepts. Those misconceptions were related to gradient wind on wind in cyclone and frictional force, related to earth rotation on western intensification of ocean current, related to angular momentum conservation and related to the roles of westerly wave. And misconceptions on greenhouse effect are related to main role of greenhouse effect gases, related to sources of ozone gas and phenomenons by atmospheric pressure. The various understanding types found in this study could be apply to teach the selected concepts in secondary school earth science course.

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

  • Yeo, Hyun-Gu;Cho, Ki-Chul;Chun, Man-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.8
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    • pp.829-835
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    • 2006
  • The composition, source, and regional concentration of polybrominated diphenyl ethers(PBDEs) were measured in pine needles with several sites in Korea. Homologs specific analysis confirmed that hepta-BDE(bromodiphenyl ethers) through deca-BDE were predictive indicator for total PBDEs concentration(Pearson's correlation coefficient r>0.96, p<0.001). Deca-BDE were detected in relatively very high concentration compared to other PBDE congeners in all samples. The similarity of between congeners profile to those of Bromkal 70-5DE and DE-71, the commercial mixture of PBDEs, indicates these mixtures are source of PBDEs observed in these sites. Also, BDE-47, -99, -100, -206, -207, and -209 were the dominant congeners in all samples, suggesting that the widely used commercial penta- and deca-BDE technical mixture were the original sources. However, Pearson's correlation coefficients of between BDE-209 and BDE-47, -99, -100 were insignificant, which implied that tetra-BDE and penta-BDE may originate from secondary sources such as air-plant partition in manner similar to that of the PCBs, while deca-BDE formulation still has primary sources.

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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    • v.52 no.2
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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.

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

  • 강미혜
    • Journal of Korean Library and Information Science Society
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    • v.23
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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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