• 제목/요약/키워드: salt concentrations

검색결과 705건 처리시간 0.031초

Growth characteristics of halophytes and forage crops under salt concentrations

  • Jeong, Jae-Hyeok;Hwang, Woon-Ha;An, Sung-Hyun;Jeong, Han-Yong;Lee, Hyeon-Seok;Baek, Jung-Sun;Choi, Kyung-Jin;Lee, Geon-Hwi;Chung, Nam-Jin;Yun, Song Joong
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.355-355
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    • 2017
  • South Korea is largely dependent on imports of forage crops. In order to raise the self-sufficiency rate of forage crops, it is necessary to cultivate forage crops in 135,100 ha reclaimed land of South Korea. This study was conducted to investigate the growth of halophytes and forage crops in order to search for stable plants on reclaimed land. The plants were cultured in Hoagland solution and grown at 0%, 0.5%, 1.0% and 2.0% of salt concentrations. Plants with good growth at 0.5% of salt concentration were halophytes such as Suaeda asparagoides and Salsola komarovii. Salicornia herbacea and Suaeda maritima showed good growth at 2.0% salinity, and Suaeda maritima showed stable growth at all of salt concentrations. In conclusion, Suaeda asparagoides showed the best growth at 0.5% of salt concentration and was considered the most biomass at reclaimed land in Korea with less than 0.5% of salt concentration.

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Corrosion of Containment Alloys in Molten Salt Reactors and the Prospect of Online Monitoring

  • Hartmann, Thomas;Paviet, Patricia
    • 방사성폐기물학회지
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    • 제20권1호
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    • pp.43-63
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    • 2022
  • The aim of this review is to communicate some essential knowledge of the underlying mechanism of the corrosion of structural containment alloys during molten salt reactor operation in the context of prospective online monitoring in future MSR installations. The formation of metal halide species and the progression of their concentration in the molten salt do reflect containment corrosion, tracing the depletion of alloying metals at the alloy salt interface will assure safe conditions during reactor operation. Even though the progress of alloying metal halides concentrations in the molten salt do strongly understate actual corrosion rates, their prospective 1st order kinetics followed by near-linearly increase is attributed to homogeneous matrix corrosion. The service life of the structural containment alloy is derived from homogeneous matrix corrosion and near-surface void formation but less so from intergranular cracking (IGC) and pitting corrosion. Online monitoring of corrosion species is of particular interest for molten chloride systems since besides the expected formation of chromium chloride species CrCl2 and CrCl3, other metal chloride species such as FeCl2, FeCl3, MoCl2, MnCl2 and NiCl2 will form, depending on the selected structural alloy. The metal chloride concentrations should follow, after an incubation period of about 10,000 hours, a linear projection with a positive slope and a steady increase of < 1 ppm per day. During the incubation period, metal concentration show 1st order kinetics and increasing linearly with time1/2. Ideally, a linear increase reflects homogeneous matrix corrosion, while a sharp increase in the metal chloride concentration could set a warning flag for potential material failure within the projected service life, e.g. as result of intergranular cracking or pitting corrosion. Continuous monitoring of metal chloride concentrations can therefore provide direct information about the mechanism of the ongoing corrosion scenario and offer valuable information for a timely warning of prospective material failure.

Olefin Separation Performances and Coordination Behaviors of Facilitated Transport Membranes Based on Poly(styrene-b-isoprene-b-styrene)/Silver Salt Complexes

  • Lee, Dong-Hoon;Kang, Yong-Soo;Kim, Jong-Hak
    • Macromolecular Research
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    • 제17권2호
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    • pp.104-109
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    • 2009
  • Solid-state facilitated, olefin transport membranes were prepared by complexation of poly(styrene-b-iso-prene-b-styrene) (SIS) block copolymer and silver salt. Facilitated olefin transport was not observed up to a silver mole fraction of 0.14, representing a threshold concentration, above which transport increased almost linearly with increasing silver salt concentration. This was because firstly the silver ions were selectively coordinated with the C=C bonds of PI blocks up to a silver mole fraction of 0.20, and secondly the coordinative interaction of the silver ions with the aliphatic C=C bond was stronger than that with the aromatic C=C bond, as confirmed by FT-Raman spectroscopy. Small angle X-ray scattering (SAXS) analysis showed that the cylindrical morphology of the neat SIS block copolymer was changed to a disordered structure at low silver concentrations ($0.01{\sim}0.02$). However, at intermediate silver concentrations ($0.15{\sim}0.20$), disordered-ordered structural changes occurred and finally returned to a disordered structure again at higher silver concentrations (>0.33). These results demonstrated that the facilitated olefin transport of SIS/silver salt complex membrancs was significantly affected by their coordinative interactions and nano-structural morphology.

Distribution of Zirconium Between Salt And Bismuth During A Separation From Rare Earth Elements By A Reductive Extraction

  • S. W. Kwon;Lee, B. J.;B. G. Ahn;Kim, E. H.;J. H. Yoo
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2004년도 Proceedings of the 4th Korea-China Joint Workshop on Nuclear Waste Management
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    • pp.165-169
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    • 2004
  • It was studied on the reductive extraction between the eutectic salt and Bi metal phases. The solutes were zirconium and the rare earth elements, where zirconium was used as the surrogate for the transuranic(TRU) elements. All the experiments were performed in a glove box filled with argon gas. Two types of experimental conditions were used -high and low initial solute concentrations in salt. Li-Bi alloy was used as a reducing agent to reduce the high chemical activity of Li. The reductive extraction characteristics were examined using ICP, XRD and EPMA analysis. Zirconium was successfully separated from the rare earth elements by the reductive extraction method. The LiF-NaF-KF system was favorable among the fluoride salt systems, whereas the LiCl-KCl system was favorable among the chloride salt systems. When the solute concentrations were high, intermetallic compounds were found near the salt-metal interface.

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Effect of Saline Concentrations on Biological Nitrification in Batch Reactor

  • Lee, Young Joon;Nguyen, Viet Hoang;Nguyen, Hong Khanh;Pham, Tuan Linh;Kim, Gi Youn
    • 통합자연과학논문집
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    • 제4권2호
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    • pp.103-112
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    • 2011
  • This study was carried out on 4 batch reactors to determine the specific ammonium oxidizing rate (SAOR), specific nitrate forming rate (SNFR) and inhibitory degree of nitrifying activities with saline concentrations. Under salt free condition ammonia was consumed during the reaction period within 200 min. When the salt level increased to 10, 20 and 30 g $NaClL^{-1}$ in reactor, ammonia depletion took 250, 300 and above 350 min, respectively. During concentration above 10 g $NaClL^{-1}$, there was nitrite accumulation. Also, at 30 g $NaClL^{-1}$ ammonia did not depleted and $NO_2{^-}$-N accumulated until the final reaction. Nitrate formation rates decreased with increasing salt concentration. SAOR and SNFR showed a decreasing trend as salinity concentrations were increased. The SAOR was reduced from 0.2 to 0.08 mg $NH_4{^+}$-N $g^{-1}VSS\;day^{-1}$ as the salt concentration increased from 0 to 30 g $NaClL^{-1}$. Similarly, the SNFR decreased from 0.26 kg $NO_3{^-}$-N $kg^{-1}VSS\;day^{-1}$ at saline free to 0.1 kg $NO_3{^-}$-N $kg^{-1}VSS\;day^{-1}$ at saline 30 g L-1. A severe inhibition of nitrifiers activity was observed at increased salt concentrations. The inhibition ratio of specific ammonium oxidation rates were 17, 47 and 60% on the reactor of 10, 20 and 30 g $NaClL^{-1}$ added, respectively. The inhibition ratio of specific nitrate forming rates also were inhibited 30, 53 and 62% on the reactor of 10, 20 and 30 g $NaClL^{-1}$ added, respectively. As the salinity concentrations increased from 0 to 30 mg $NaClL^{-1}$, the average MLSS concentration increased from 1,245 to 1,735 $mgL^{-1}$. The SS concentration of supernatant in reactor which settled about 30 minutes was not severely difference between concentration of salt free reactor and one of those high salt contained reactors.

배추절임시 염수농도와 침지온도 및 시간에 따른 특성 변화 (Characterization cf salted Chinese cabbage in relation to salt content, temperature and time)

  • 심영현;안기정;유창희
    • 한국식품조리과학회지
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    • 제19권2호
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    • pp.210-215
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    • 2003
  • 오늘날 우리의 김치제조는 가정 내 소규모 제조보다는 산업화, 공장화 제품으로 변화되어 가는 추세이다. 현장에서 도움이 되면서도 질적으로 우수한 김치 제조를 위한 가장 기초라 할 수 있는 절임 공정은 무시 될 수 없는 부문이기에 본 실험에서도 배추 절임 시 가장 중요한 염 용액의 농도와 절임 시 온도변화 절임 시간을 달리해 절임 배추의 조직감에 대한 기초자료 확립에 목적을 두었다. 최적염도 2.8 도달점과 조직감을 살펴볼 때 10% 염용액 $25^{\circ}C$ 10시간째, 15%염용액 $25^{\circ}C$ 6-8시간대에서 가장 빨리 도달한다. 조직감은 10-15% 염용액에서 6-10 시간대에서 우수한 질감으로 나타났다. 결과적으로 온도가 올라갈수록 적정 염농도인 2.80에 도달하는 시간이 각 시료마다 다르고 조직감에서는 질긴 조직감보다는 신선하고 청량감을 줄 수 있는 조직감을 보이는 시료가 10% 염용액, $25^{\circ}C$, 10시간째, 15%, $25^{\circ}C$, 6-8 시간째로 염농도 도달점, 조직감이 일치하므로 절임시간과 온도, 염용액의 염도를 보정함이 맛과 영양적으로 우수 할 뿐만 아니라 시간적, 경제적인 부문에서도 많은 경감효과를 가지고 올 수 있다고 본다.

해수의 염 농도와 탁도가 전기, UV 및 전기+UV 공정의 Artemia sp. 불활성화에 미치는 영향 (Effect of Salt Concentration and Turbidity on the Inactivation of Artemia sp. in Electrolysis UV, Electrolysis+UV Processes)

  • 김동석;박영식
    • 한국환경과학회지
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    • 제28권3호
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    • pp.291-301
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    • 2019
  • This study was conducted to investigate the effect of salt concentration and turbidity on the inactivation of Artemia sp. by electrolysis, UV photolysis, electrolysis+UV process to treat ballast water in the presence of brackish water or muddy water caused by rainfall. The inactivation at different salt concentrations (30 g/L and 3 g/L) and turbidity levels (0, 156, 779 NTU) was compared. A decrease in salt concentration reduced RNO (OH radical generation index) degradation and TRO (Total Residual Oxidant) production, indicating that a longer electrolysis time is required to achieve a 100% inactivation rate in electrolysis process. In the UV process, the higher turbidity results in lower UV transmittance and lower inactivation efficiency of Artemia sp. Higher the turbidity resulted in lower ultraviolet transmittance in the UV process and lower inactivation efficiency of Artemia sp. A UV exposure time of over 30 seconds was required for 100% inactivation. Factors affecting inactivation efficiency of Artemia sp. in low salt concentration are in the order: electrolysis+UV > electrolysis > UV process. In the case of electrolysis+UV process, TRO is lower than the electrolysis process, but RNO is more decomposed, indicating that the OH radical has a greater effect on the inactivation effect. In low salt concentrations and high turbidity conditions, factors affecting Artemia sp. inactivation were in the order electrolysis > electrolysis+UV > UV process. When the salt concentration is low and the turbidity is high, the electrolysis process is affected by the salt concentration and the UV process is affected by turbidity. Therefore, the synergy due to the combination of the electrolysis process and the UV process was small, and the inactivation was lower than that of the single electrolysis process only affected by the salt concentration.

벼 세포적기에 미치는 염분 농도의 영향 (Effect of Salt on Mitotic Cycle in Root Meristem Cells of Rice)

  • 김재철;권성환;이진재;이영일
    • 한국작물학회지
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    • 제37권5호
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    • pp.397-404
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    • 1992
  • 본 연구는 내염성이 비교적 강한 Japonica형 품종인 섬진벼와 내염성이 비교적 약한 통일형 품종인 칠성벼를 염분농도에 따른 세포주기를 측정하고 각 phase의 기간 변화도 조사하였으며, 또한 DNA, RNA 및 단백질 합성량를 제출하여 세포주기와 어떠한 관련성이 있는지를 조사한 결과 다음과 같다. 1. 섬진벼와 칠성벼의 세포주기는 염분농도 0%, 0.3% 및 0.6%에 서 12시간으로 동일하였다. 2. 세포주기로부터 측정된 각 phase 별 기간은 무처리구와 처리구에서 차이를 보였다. 섬진벼가 무처리구에서 G1=3.3, S=3.8, G2=2.8, 그리고 M=2.1 시간이었고, 0.3%에서 G1=3.5, S=3.6, G2=2.8, 그리고 M=2.1 시간이었으며, 0,6%에서 G1=3.5, S=3.6, G2=2.8, 그리고 M=2.1 시간으로 무처리구에 비하여 G1 기간은 길어겼고, S 기간은 약간 짧아졌다. 칠성벼에서는 무처리구에서 G1=2.6, S=5.2, G2=2.3, 그리고 M=1.9 시간이었고, 0.3%에서 G1=2.5, S=6.2, G2=1.6 그리고 M=1.7 시간이었으며, 0.6%에서 G1=2.1, S=6.0, G2=2.0 그리고 M=1.9 시간으로 무처리구에 비하여 처리구의 G1과 G2 기간은 짧아졌고 S 기간은 길어졌으며, 이는 섬진벼의 변화와 반대 성향을 보여 주었다. 3. 섬진벼에서 처리구가 무처리구에 비하여 DNA와 RNA 합성은 감소한 반면, 단백질 합성은 증가하였으며, 칠성벼에서는 처리구가 무처리구에 비하여 DNA와 단백질 합성은 증가하였으나, RNA 합성은 섬진벼와 같이 감소하였다.

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Effects of Salt Treatment on Seed Germination and Plant Growth of Korean Native Apocynum lancifolium Russanov

  • Kim, Jo-Hoon;Park, Ye-Gun;Ann, Seoung-won;Baik, Jung-Ae;Park, Dong-Jin
    • 한국환경과학회지
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    • 제30권11호
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    • pp.957-965
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    • 2021
  • This research was carried out to investigate seed germination and growth of the perennial plant Apocynum lancifolium under different NaCl concentrations, with a view for future cultivation on reclaimed land. Initial characterization revealed that the average length and weight of A. lancifolium seed pods was 133.6 mm and 0.23 g, respectively, and the thousand-grain weight was 0.59 g. Upon examining the effects of light on seed germination, we found germination to be 1.7% higher under light conditions (90%) than under dark conditions (88.3%). In terms of the response to salt stress, we found that 90% of seeds germinated in the 0.00%, 0.25%, and 0.50% salt treatment groups. Although salt treatment up to a concentration of 0.5% was found to have little effect on seed germination, the rate of germination decreased at higher concentrations and was completely inhibited in the 2% treatment. We also established that germination rates were higher in seeds sown in horticultural topsoil than in the coarse sandy soil found in the plant's natural habitats. Although the growth of A. lancifolium tends to decrease with an increase in salt concentration, we found that the stem thickness, fresh weight, and dry weight of A. lancifolium seedlings subjected to 0.25%-1.0% salt were comparable to those of the control seedling that were not exposed to salt. Furthermore, in contrast to those plants subjected to 2.0% salt, these plants continued to grow and remained viable.

염생식물 나문재의 여러 가지 환경 조건 하에서의 종자 발아 및 초기생장특성 (Germination and Early Growth Characteristics of the Halophyte Suaeda Asparagoides Under Various Environmental Conditions)

  • 권혁규;정재혁;이승재;정남진
    • 한국작물학회지
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    • 제61권3호
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    • pp.222-226
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    • 2016
  • 본 연구는 토양 염농도의 변이가 큰 간척지에서 염생식물 나문재의 안정적인 재배와 생산을 위한 연구의 하나로, 나문재 종자의 발아특성과 초기생육특성을 구명하고자 실시하였다. 나문재 종자는 무배유 쌍자엽 구조를 가지며 별 모양의 황색 화피에 싸여 있다. 종자크기는 길이가 4.7 mm, 너비가 4.4 mm, 그리고 두께가 3.1 mm이며, 천립중은 1.58 g이다. 종자의 발아는 $5{\sim}40^{\circ}C$의 온도범위에서 8~65%의 변이를 보이며, $15^{\circ}C$에서 가장 높았다. 염농도에 따른 발아율은 증류수에서 발아율이 가장 높았으며 염농도가 증가할수록 발아율이 감소하였다. 종자에서 화피를 제거했을 때의 발아율은 온도나 염농도에 관계 없이 모든 처리에서 유의하게 증가하였다. 종자발아에서 광의 영향을 보면, 0~300 mM의 염농도 범위에서 광조건이 암조건보다 5~20% 정도 발아율이 높게 나타났다. 한편, 염농도 따른 나문재의 초기생장을 초장, 경수, 생체중, 건물중, 근장 등으로 조사한 결과, 모든 특성들이 50~100 mM의 염농도에서 양호하였고, 증류수나 높은 농도의 염수에서는 생장이 크게 감소되었다. 결론적으로, 나문재의 발아율을 높이기 위해서는 화피를 제거한 종자를 증류수에 침종하여 $15^{\circ}C$ 정도의 저온과 광 조건에서 발아시키는 것이 유리하며, 식물체의 생장은 50~100 mM의 염농도 하에서 재배하는 것이 유리하다.