• Title/Summary/Keyword: 염 손상

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Study on the Damage Mechanism by Salt of White Porcelain Figurine in Underglaze Iron (백자 철화 인물형 명기의 염 손상 메커니즘 연구)

  • Lee, Sun Myung;Jin, Hong Ju;Yun, Ji Hyeon;Kwon, Oh Young
    • Journal of Conservation Science
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    • v.36 no.5
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    • pp.368-382
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    • 2020
  • It was confirmed that a white porcelain figurine in underglaze iron was damaged after exhibition. This study analyzes the current state of salt damage on the artifact and identifies the factors contributing to its deterioration by examining the material characteristics of the artifact and exhibition environment. The analysis will thus assist in preparing a conservation scheme for artifacts. The crystallized carbonate on the surface of the white porcelain figurine is a water-soluble alkali salt with high hygroscopicity and high solubility in water. This solubility increases as the temperature increases. The figurine was low-fired at approximately 1000℃. A lead glaze was applied, and thin cracks were formed on the glazed surface, indicating poor surface properties. Our analysis suggested that the showcase used in the exhibition likely created a moist environment resulting from condensation, as it was exposed to high temperature and relative humidity, particularly in comparison to the exhibition room where the temperature was regulated using an air conditioner. In addition, the artifacts in the showcase were exposed to sudden changes in temperature and relative humidity as the air conditioner was repeatedly turned on and off. Therefore, it can be deduced that the soluble salt remaining on the white porcelain figurine moved toward the surface of the relatively weak glaze as a result of the temperature, and the crystallized salt exacerbated surface damage as the moisture evaporated in a dry environment.

A Study on Cause Analysis and Countermeasures of Chloride Attack of Reinforced Earth Retaining Walls Installed on Bridge Abutment (염해로 인한 교대부 보강토옹벽 손상 원인 분석 연구)

  • Do, Jong-Nam;Kim, Nag-Young;Cho, Nam-Hun;You, Kwang-Ho
    • Journal of the Korean GEO-environmental Society
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    • v.19 no.12
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    • pp.59-64
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    • 2018
  • The damages to the reinforced earth retaining wall are divided into the front wall, foundation, drainage and upper slope. Damage of reinforced earth retaining wall is mainly caused by damage caused by drainage problem in the field. Recently, damage caused by snow removal materials have been occurred. Recently, the amount of snow removal materials used in winter is increasing due to abnormal weather. This chlorides degrades the concrete structure, where the reinforced earth retaining wall was no exception. There has recently been a case in which the front wall of the reinforced earth retaining wall deteriorates due to the chlorides introduced into the back filling portion through the drainage passage. Therefore, in this study, the cause of damages of reinforced earth retaining wall constructed in bridge abutment was analyzed, and an analytical study was conducted on the countermeasure. As a result, it was found that chlorides, which was introduced through the drainage system in the expansion joint of the bridge shift part or the upper structure, is infiltrated into the back part of the reinforced earth retaining wall and damaged. Therefore, it is suggested to improve the drainage system and restored the stiffness of the front wall.

Pathophysiology of Articular Cartilage Injury (관절 연골 손상의 병태 생리)

  • Park, Jung-Ho
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.4 no.1
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    • pp.6-11
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    • 2005
  • Injury of articular cartilage can be classified into acute injury and chronic degenerative osteoarthritis Acute mechanical trauma on articular cartilage causes injuries that are divided into three distinct types based on the depth of injury: microdamage, chondral fracture, osteochondral fracture and each type has different potential of healing response and long-term prognosis. Articular cartilage undergoes degradation in response to a number of stimuli and eventually degenerative osteoarthritic changes will progress. The extent of initial injury to the articular cartilage is the most important factor affecting the long-term outcome of the healing response and other variables such as the size of lesion, site, age, activity level, obesity, limb alignment are also important factors. In this review, the pathophysiology that occurs within articular cartilage after different injuries and the effect of nonsurgical treatment mainly in physicochemical aspect and biological aspect will be discussed.

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Current Update of Cartilage Regeneration Using Stem Cells in Osteoarthritis (골관절염에서 줄기세포를 이용한 연골 재생의 최신 지견)

  • Seon, Jong-Keun;Choi, Ik-Sun;Ko, Jee-Wook
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.6
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    • pp.478-489
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    • 2019
  • Osteoarthritis is a disease characterized by the progression of articular cartilage erosion, that increases pain during joint motion and reduces the ability to withstand mechanical stress, which in turn limits joint mobility and function. Damage to articular cartilage due to trauma or degenerative injury is considered a major cause of arthritis. Numerous studies and attempts have been made to regenerate articular cartilage. In the case of partial degenerative cartilage changes, microfracture and autologous chondrocyte implantation have been proposed as surgical treatment methods, but they have disadvantages such as insufficient mutual binding to the host cells, inaccurate cell delivery, and deterioration of healthy cartilage. Stem cell-based therapies have been developed to compensate for this. This review summarizes the drawbacks and consequences of various cartilage regeneration methods and describes the various attempts to treat cartilage damage. In addition, this review will discuss cartilage regeneration, particularly mesenchymal stem cell engineering-based therapies, and explore how to treat future cartilage regeneration using mesenchymal stem cells.

해양 심층수염을 이용한 무 절임시 품질특성 변화

  • 이기동;김숙경;이현아;이명희;김미림
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.04a
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    • pp.124-124
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    • 2003
  • 해양 심층수는 저온 안정성, 부영양성 및 인공물질에 오염되지 않은 해양수로서 오늘날 많은 분야에서 사용 가능성이 대두되고 있다. 해양 심층수를 음료나 식품, 화장품 등에 이용하였을 경우 나타나는 효과의 일부는 미네랄 특성과 관계가 있는 것으로 알려져 있으며, 심층수를 원료로 한 음료수에는 혈행개선 효과가 있으며, 심층수를 생수로 섭취하였을 경우 혈중 콜레스테롤치을 유의적으로 낮추는 것으로 알려져 있으며, 간장의 인지질 값도 낮춘다는 연구보고가 있다. 또한 해양심층수는 아토피성 피부염에 효과가 있으며, 식품의 맛을 개선하는 것으로도 알려져 있다. 우리나라의 대표적인 음식인 김치는 배추, 무 둥을 식염으로 절여 각종 채소류 및 향신료를 첨가한 후 젖산발효를 적절하게 시켜 숙성한 채소발효식품으로 세계적인 음식으로서 각광받고 있다. 이 중 무는 천일염이나 정제염에 절여서 깍두기나 동치미 등에 사용되기도 하며, 김치의 재료로 배추 다음으로 이용율이 높은 김치소재이다. 무는 절임여하에 따라서 김치의 맛, 품잘, 미생물의 번식속도, 저장성 등이 변화하며, 절임이 중요한 품질요소로 알려져 있다. 소금의 종류 및 소금의 사용방법에 따른 무의 품질특성의 변화에 대한 연구들이 있으나 해양 심층수염을 이용하여 무를 절임시 품질특성에 대한 연구는 이루어져 있지 않는 실정이다. 이에 본 실험에서는 해양 심층수염에 무의 절임에 따라 무의 절임 특성 변화를 관찰하였다. 해양 심층수염과 천일염을 이용하여 무를 절임할 경우 수축율, 염도, 물성의 특성 변화를 관찰하였다. 해양 심층수염을 가지고 무를 절임할 경우 특성 변화를 살펴본 결과 수축률은 절임 8시간 이후에 해양 심층수염으로 절임한 경우가 천일염으로 절임한 경우보다 큰 것으로 나타났으며, 해양 심층수염이 천일염보다 더 높은 염도를 나타내며 절임되었다. 젤리강도는 절임시간이 증가함에 따라 감소하는 경향을 나타내었으며, 절임 염도가 높을수록 젤리강도는 낮아지는 경향을 나타내었다. 무의 연도(Softness)는 심층수염이 천일염보다 높은 값을 나타냄으로서 해양 심층수염에 절일 때 더 부드러운 물성을 나타냄을 볼 수 있었다. 견고성은 해양 심층수염에 절임하는 것이 천일염에 절임하는 것보다 더 높은 값을 나타났다. 해양 심층 수염이 천일염보다 빨리 무 조직에 손상을 줌으로 절임을 단축시키지만 절임시간이 연장되면 오히려 무 조직의 손상을 완화시키는 것으로 나타났다. 이러한 차이는 김치맛과 발효에도 영향을 미치는 품질 요인이 될 수 있을 것으로 판단되며, 해양 심층수염을 이용하여 김치발효시 특성 변화에 대해 더 구체적인 연구가 필요하리라 사료된다.

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Changes of Quality Characteristics of Radishes Salted with Deep Seawater Salt (해양 심층수염을 이용한 무 절임시 품질특성 변화)

  • 이기동;김숙경;이현아;이명희;김미림
    • Food Science and Preservation
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    • v.10 no.2
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    • pp.182-186
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    • 2003
  • This study was carried out to observe the property changes of radishes salted with different salt (deep sea water and sun-dried salt). Shrinkage rate, salinity and texture were measured. The shrinkage rate values of radishes salted with deep seawater salt solution were higher than those salted with sun-dried salt in 8 hr after salting. The salinity of radishes salted with deep seawater salt solution was also higher than those salted with sun-dried salt. The jelly strength decreased during salting period and 5% salting radish were lower than 3% ones. The softness and hardness of radishes salted with deep seawater salt were higher than those salted with sun-dired salt as well.

Analysis of Correlation between Freeze-Thaw Damage on Concrete and Chloride Penetration Acceleration Effect Using Surface Rebound Value (표면반발경도 활용 콘크리트 동해손상과 염분 침투 가속효과의 상관관계 분석)

  • Park, Ji-Sun;Lee, Jong-Suk
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.26 no.6
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    • pp.148-156
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    • 2022
  • Although most domestic concrete structures are simultaneously exposed to freeze-thaw and chloride environments, concrete durability in the field is evaluated by each single action, and the evaluation of chloride-caused damage of concrete requires additional indoor experimental analysis of chloride contents by coring samples from structures in the field. However, in Korea, policies to strengthen facility maintenance, such as 「Special Act on the Safety Control and Maintenance of Establishments」 and 「Framework Act on Sustainable Infrastructure Management」, have been established and implemented since 2018 and facilities subject to safety inspection management by the government and local governments increases, the effective simplification technology for the inspection and diagnosis of concrete structure is needed. Therefore, this study attempted to evaluate the possibility of determining the acceleration chloride penetration of freeze-thaw damaged concrete by using the surface rebound value. For this purpose, concrete specimens already having freeze-thaw damage by exposure to the freeze-thaw acceleration environment were immersed in chloride water. After that, the acceleration relationship of chloride penetration according to freeze-thaw damage was analyzed using the amount of chloride contents in concrete.

Influence of Salts on Consolidation of Nebra Sandstone (네브라 사암의 강화처리에 미치는 염의 영향)

  • Do, Jin-Young
    • Journal of Conservation Science
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    • v.18 s.18
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    • pp.89-96
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    • 2006
  • Surface layers of stone cultural properties including the soluble salt need consolidation because they are mostly very weak. There is a lot of research on the penetration depth of consolidant in stone and the effect of consolidant on mechanical stability of deteriorated structure. But some conservation experiences show that consolidation with silicic acid ester is not successful on salt contaminated stone cultural properties. In this study, in order to assess the influence of soluble salts$(CaSO_4\;2H_2O,\;NaNO_3)$ on the efficiency of consolidation on the deteriorated stone cultural properties(Nationalgalerie, Berlin, Germany) sandstone samples have been soaked with the salts solution. The impregnation of consolidant based on ethyl filicate have been afterwards carried out on these samples. As a result, it confirms that the soluble salts act as a preventer or consolidation. They fill up the pores in the stone and prevent that sufficient amount of consolidant enter deeply into the stone. According to this result, if use silicic ethyl ester as a consolidant for the research object which is built by Nebra sandstone, desalination is necessary before the treatment with consolidant. But it is also reported by other researches that some soluble salts improve the consolidation effect. Therefore it should be necessary to pre-study about salt and its harmfulness before the consolidation treatment. In order to consolidate without the aggravative damage in salt contaminated stone cultural heritage, we must first of all study the relations among salt, stone and consolidant.

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Radiation-Induced Proctitis in Rat and Role of Nitric Oxide (백서모델에서 방사선 직장염 유발인자로서의 Nitric oxide의 역할)

  • Chun Mison;Kang Seunghee;Jin Yoon-Mi;Oh Young-Taek;Kil Hoon-Jong;Oh Tae-Young;Ahn Byoung-Ok
    • Radiation Oncology Journal
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    • v.19 no.3
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    • pp.265-274
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    • 2001
  • Purpose : Proctitis is one of acute complications encountered when radiotherapy was appled to the pelvis. Radiation-induced proctitis represents similar microscopic findings that are observed in inflammatory bowel disease (IBD). Nitric oxide (NO) plays an important role in the inflammatory process and many data suggest a close relationship between NO production and gastrointestinal inflammation. This study was aimed to establish the optimal radiation dose for radiation-induced proctitis in rat and to find a relationship between radiation proctitis and NO production. Materials and methods : Female Wistar rats, weighing from 150 to 220 g, received various doses(10-30 Gy) of radiation to the rectum. On the 5th and 10th day after irradiation, rectal specimens were evaluated grossly and microscopically. In addition, the degree of NO production by irradiation dose was evaluated by study with NOS expression and nitrite production in the irradiated rectal tissue. To evaluate relationship between radiation proctitis and NO, we administered aminoguanidine, iNOS inhibitor and L-arginine, substrate of NOS to rats from 2 days before to 7 days after the irradiation. Results : There were obvious gross and hostological changes after 17.5 Gy or higher radiation dose but not with 15 Gy or less radiation dose. Twenty Gy or higher dose of radiation caused Grade 4 damage in most of rectal specimens which were more likely to be related to the late complications such as fibrosis, rectal bleeding and rectal obstruction. A single fraction of 17.5 Gy to the rat rectum is considered to be an optimal dose to produce commonly experienced proctitis in the clinic. The result demonstrated that severity of microscopic damage of rectal mucosa from irradiation significantly correlated with iNOS over-expression. However, administration of iNOS inhibitor or substrate of iNOS did not influence the degree of rectal damage. Conclusion : A single fraction of 17.5 Gy irradiation to the rat rectum considered to be an optimal dose for radiation induced proctitis model. These results indicated that an excess production of NO contributes to pathogenesis of radiation-induced proctitis in part but was not the direct cause of rectal damage.

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Study on Liquid Walls for Fusion Device (핵융합 장치를 위한 액체 벽 연구)

  • Choe, Yong-Seop;Park, Hyeon-Jae;No, Tae-Hyeop
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2012.11a
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    • pp.34-34
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    • 2012
  • 핵융합 장치의 액체 벽 연구에 관해 정리 하였다. 액체 벽은 1970년 Field Reversed Configuration 장치의 first wall로써 Christofilos에 의해 처음으로 제안되었다. 액체 벽은 순환을 통해 벽 손상을 막을 수 있는 장점이 있으나, 플라즈마와의 반응 시 증발로 인한 중심 플라즈마 불순물 증가 문제와, 진공 용기 내벽에 유동을 만들어야 하는 어려움이 있다. 본 논문에서는 그 동안 제안된 액체 벽 개념에 관한 검토와 국가핵융합 연구소 플라즈마 기술연구센터에서 수행하고 있는 액체 벽 관련 연구에 대해서 발표하고자 한다. 국가핵융합 연구소 플라즈마 기술연구센터에서는 용융염(FliNaK, LiF+NaF+KF)을 이용하여 수소 플라즈마와 용융염과의 반응에 관한 기초 연구를 수행하여 왔다. 기초 연구로써 수소 플라즈마 반응 유무에 따른 용융염 증발특성 변화, 용융염 내 수소 함유량 변화 측정, 수소 플라즈마 반응 시 광 진단을 통한 용융염 증발 성분 확인 등의 연구를 수행하였다. 또 진공 챔버 내부에 용융염 순환 시스템을 제작하여, 흐르는 용융염과 플라즈마와의 반응을 연구할 수 있는 실험 장치를 최근 제작 설치하였다. 본 논문에서는 중요한 기초 실험 결과와 용융염 순환 시스템 설계 인자에 대해서 논의하고자 한다.

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