• Title/Summary/Keyword: critical phenomena

Search Result 401, Processing Time 0.022 seconds

Crystal Structure and Mossbauer Studies of 57Fe Doped TiO2 (57Fe가 치환된 TiO2의 결정학적 및 뫼스바우어 분광학적 연구)

  • Lee, Hi-Min;Shim, In-Bo;Kim, Chul-Sung
    • Journal of the Korean Magnetics Society
    • /
    • v.13 no.6
    • /
    • pp.237-242
    • /
    • 2003
  • $Ti_{1-x}$$^{57}$ F $e_{x}$ $O_2$(0.0$\leq$x$\leq$0.07) compounds were fabricated using the sol-gel method, and the crystal structure and magnetic properties were investigated as a function of doped $^{57}$ Fe concentration. X-ray diffraction patterns showed a pure anatase single phase, without any segregation of Fe into particulate. With varying $^{57}$ Fe concentration, we could observe unusual magnetic phenomena in these materials. Doping $^{57}$ Fe into the Ti $O_2$ nonmagnetic semiconductor formed magnetic properties, but the gradual increase of $^{57}$ Fe concentration decreased rapidly the ferromagnetic properties rather than enhanced the ferromagnetic properties. Obvious ferromagnetic behavior was shown for the samples with x$\leq$0.01, while paramagnetic behavior was shown for the sample with x$\geq$0.03. These phenomena could be verified using Mossbauer measurement. Separation of the ferromagnetic phase (sextet) and the paramagnetic phase (doublet) of the samples with different $^{57}$ Fe concentration was characterized. Samples with x$\leq$0.01 have sextet and doublet simultaneously, but samples with x$\geq$0.03 have only doublet at room temperature. This indicates that the sample x$\leq$0.01 have the ferromagnetic phase at room temperature. This result corresponded with the M-H loops referenced above and reveals an interesting feature that there is a critical limit of $^{57}$ Fe concentration (0.01$\leq$0.01 samples was fundamentally attributable to the paramagnetic phase as well as the ferromagnetic phase.e.

Choi Chi-won, the Originator of Jeongeup Museongseowon and Scholar Culture (정읍 무성서원과 선비문화 원류 최치원)

  • An, Young-hoon
    • Journal of the Daesoon Academy of Sciences
    • /
    • v.40
    • /
    • pp.243-272
    • /
    • 2022
  • Jeongeup, Jeollabuk-do, is an area that requires attention from those who study the history of Korean thought. In addition, Jeongeup is an area wherein many works were recorded for the first time in literary history. This is the case with Jeongeupsa as a style of Baekje songs and the lyrics of the noble families of the Joseon Dynasty, Sangchungok. Jeongeup is likewise the location where Choi Chi-won (857~?) was selected to serve as a local taesu (viceroy) and where a unique tradition of music and style were passed down. In this paper, the relationship between Choi Chi-won's role in the process of establishing a silent Confucian academy in Jeongeup and the emergence of scholar culture was examined. When Choi Chi-won left after his term in office, a birth shrine called Taesansa Temple was built to repay the selection of the villagers, and it became the source that led to the opening of the Confucian academy Museongseowon in the future. Jeongeup will be shown to be the location where Choi Chi-won realized his aspirations and honed his capabilities. In particular, Choi Chi-won's played a crucial role in the mid-Joseon Dynasty by supporting the construction and securing the name of Museongseowon. That is why Choi Chi-won was able to be revived as a symbolic figure in the region. In addition, it can be seen that the shape of Choi Chi-won was more sedentary- in the form of a Confucian scholar- and Confucian scholars emphasized the transfer of portraits at Museongseowon. Through the poetry written by Choi Chi-won, readers can learn about the worries and perceptions of scholars during those times. Although his value in the field of poetry is diverse, he can especially be recognized as a Confucian intellectual. In a large number of his works, he expresses his anxiety, agony, and critical inner consciousness all of which came from his encounter with the realities of his time. In fact, Choi Chi-won showed his qualities as a prominent literary figure of his time who had extraordinary aspirations and an admirable work ethic. However, he failed to overcome his regional and mental alienation as a poet in neighboring countries. Therefore, he internalized a sort of fierceness in terms of his perception of the world. However, it seems that it was rather a factor that made his work exhibit a strong lyrical style. In addition, Choi Chi-won's collection of writings includes a number of works that strongly criticized various forms of pathological phenomena caused by terminal phenomena of the time. He also highlighted the wrong in society by realistically depicting the lives poor and needy people and their eventual sacrifice via distorted relationships. This can be read encapsulating the agony of intellectuals of that time. The dictionary definition of a 'Confucian scholar' is "a Confucian term referring to a person or class that embodies Confucian ideology," and in its contemporary meaning it suggests " ⋯ an example of a personality, but not an identity, and the conscience of one's time period as a source of human morality inwardly and social order outwardly." In this respect, it could even be said that Choi Chi-won could be considered the originator of scholar culture.

Study on the Response of Korean Ginseng (Panax ginsen◎ C.A. Meyer) to the Herbicide 2,4-D Application

  • Jo, Jae-Seong
    • Proceedings of the Ginseng society Conference
    • /
    • 1990.06a
    • /
    • pp.149-154
    • /
    • 1990
  • Various rates of 2, 4-2 were sprayed on 2 and 3 year old ginseng plants as fouler spray to define the critical concentration. No apparent plant injury was noticeable for those ginseng plants when application concentration of 2, 4-D doubled the recommended dosage (70 mil 10a). Neither abnormal fouler change occurred nor any inhibition in leaf and stem growth was resulted for the plants treated with 2, 4-D concentrated two times of the recommended dosage. When the rates of 2, 4-D application were increased greater than this level, injury ratings increased linearly with the rates of 2, 4-D application and plant growth was inhibited. Ethylene gas was not produced from the ginseng plant treated with 2 times concentrated 2, 4-D, how- ever the ginseng plants produced 0.03 to 0.09 ppd ethylene gas when the rate of application were increased 3 and 4 times, respectively. On the other hand the soybean treated with the recommended amount of 2i-D produced ethylene gas of 10-20 times higher compared with ginseng plants and died. Photosynthesis ability of the ginseng leaf was significantly decreased by 2, 4.D fouler application but it was recovered 4 weeks after 2, 4-D fouler treatment. The herbicide 2, 4-D was appreciated to 2, 3 and 4 years old ginseng plants as fouler spray with the rates of 0.5, 1.0, 1.5 and 2.0 times of the recommended dosage to define the effects of 2, 4-D on the plant growth and root yield of the ginseng, There were no significant differences in the leaf and stem growth between untreated and 2, 4-D treated plant. Berry maturing of 3 and 4 year old ginseng was not influenced by 2, 4-D. The root weight of 4 years old ginseng plant was not reduced b). application of 2, 4-D concentrated 2 times of the recommended dosage. Application time of the herbicide 2, 4-D had no effects on the leaf or stem growth of 2, 3 and 4 year old year old ginseng plants. When the ginseng seedling was treated with 2, 4-D, detrimental phenomena as stem bending and deceleration of seedling leaf margin occurred, but stem bending was recovere d in a few day.

  • PDF

Icon and Form: A Study on Iconic Images of Cultural Revolution in Contemporary Chinese Fine Art (도상과 형상: 중국현대미술에서 문혁의 도상이미지 연구)

  • Li, Yongri
    • The Journal of Art Theory & Practice
    • /
    • no.16
    • /
    • pp.225-256
    • /
    • 2013
  • As the great catastrophe in the modern and contemporary history of China, the Cultural Revolution(CR) is an object, which must have sutured the past of darkness. At the same time it is a continuous event and also a scar of memory. In other words, for history is "a dialog between the past and the reality"(E.H.Kar), CR intervenes in the reality and, on the contrary, the reality recomposes CR. From this point of view, CR is a historical event, which so far is not ended, and it is an object of memory, which is still being composed at the moment. As the saying: "Poetry is greater than history"(Aristoteles), artistic works more intensively reflect the past. The works related to CR can not be an exception. And CR is endlessly exposed in the contemporary Chinese fine arts and the works of the contemporary Chinese artists-Wang Guangyi, Yue Minjun, Zhang Xiaogang and others are proved to be those who suffer from the trauma of CR and who feel no liberty from CR. For example, CR probably is a symbol showing the "identity" of the Chinese artists. And the diversity of the symbol is the experience and pattern of the dialog between artistic works and CR (i.e., intervention in reality). For example, with withering of grand-narrative and appearance of micro-narrative, the CR critical works of Guan Zhoudao were the root of the Chinese fine arts in the late 70s and early 80s. In the contemporary cultural situation, the literary works about CR actively analyzed the history (CR) from the personal point of views and explained in the way of monolog and micro-method led the 1990s' works. In this way they tried to recompose the history "randomly", like looking at reality with their own eyes. In this process, CR is continuously exposing new features and the real facts are appearing before us as unfamiliar phenomena. This is a way of combination and "reappearance" of contemporary arts and reality. In conclusion, the purpose of this article is to make it possible to see a section of the contemporary Chinese fine arts through the study of the icon image of CR and to analyze the way of fine arts recomposing the history and the intervening in the reality. In this sense, the author has entitled the article "Icon and Form". It means how to reshape (the present) the typically formed icon of the CR (the past).

  • PDF

A Study on the Archaeological Landscape-painting of the 18th century: Focusing on the Capriccio of Giovanni Paolo Pannini (18세기 고고학적 풍경화에 대한 연구: 파니니의 카프리초를 중심으로)

  • Kim, Jung Rak
    • The Journal of Art Theory & Practice
    • /
    • no.16
    • /
    • pp.175-199
    • /
    • 2013
  • Capriccio which has emersed in Italy of the 18th century is a new genre of the landscape painting. This genre represents reality, but it is very artificial product correspondingly its concept and character. It's birth place is distributed on various regions in Italy, but the main stage was Rome. Till the middle of the 18th century Rome was the Holy city of the Grand tour, the home of the Neo-Classicism and furthermore the field where archaeology and art history began to be instituted. On such historical situation the Capriccio came out and was recognized as the best popular genre in the visual art. It was favor of the art collection with the antiquity together and reflected the consciousness of the contemporary to the ancient. This study will examine the phenomena in the newly-developed archaeology and with few representative works of Giovanni Paolo Pannini as central term consider the Capriccio and the archaeological connotation. The systematical and institutional archeology which appeared at the age of the Enlightenment, on the contrary to the critical theories at the same time against capriccio, because it was regarded by them as paradoxical and too much sensitive, utilized it as a theoretical method very actively. Some among Historians and archaeologists did it, especially Francesco Bianchini distinguished the capriccio from simple imagination and made it a capacity of the knowledge. And through it he wanted to find out the historical truth. The visual art was influenced and encouraged by such attitude of the archaeology. However it's output spreaded out in various courses. While Giovanni Battista Piranesi, the best known Capriccist of the 18th century, tried to revive the antique through the epical value and his own imagination, Pannini gave priority to the strict historical research. In the such context Panni succeed Giovanni Battista Nolli who made the great map of the city Rome. Their Capriccio profited motive and was inspired by the historians and archaeologists such as Bianchini and Muratori. The Capriccio reflects not only the academic and popular interest for the antique, but also influenced on the upcoming scientific archaeology vice versa. It caused by their reasonable Interpretation and restoration of the antique through the visual medium. Finally as archaeological landscape Pannini's Capriccio is a historical case, in that the Capriccio applied the theoretical method of the archaeology to make art. It served as a momentum for the connotation to the archaeological thought.

  • PDF

Interfacial Phenomena of Dodecyl Ether Sulfates Containing Various Ethylene Oxide(EO) and Isopropylene Oxide(PO) (EO, PO가 부가된 도데실 에테르 황산화물의 계면성)

  • Yoo, Young-Chang;Kim, Sang-Chun;Kim, Tae-Young;Ju, Myung-Jong;Nam, Ki-Dae
    • Applied Chemistry for Engineering
    • /
    • v.7 no.2
    • /
    • pp.299-307
    • /
    • 1996
  • The surface tension of PO added sodium poly(oxyethylene(EO), oxyisopropylene(PO)) dodecyl ether sulfate firstly were slightly lower than EO added sulfate in the concentration range of $10^{-6}{\sim}10^{-3}mol/{\ell}$. And they had lower critical micelle concentration ($10^{-4}{\sim}9{\times}10^{-5}mol/{\ell}$) than general anionic surfactants. The adsorptivity ($2.2{\times}10^{-10}mol/cm^2$) of sodium $(PO)_{10}(EO)_5$ dodecyl ether(compound of PO addition firstly) calculated by Gibbs' adsorption isotherm were higher than that of sodium $(EO)_{10}(PO)_5$, dodecyl ether(compound of EO addition firstly), but were lower than that of sodium dodecyl sulfate (${\Gamma}=3.2{\times}10^{-10}mol/cm^2$). These could be understood that the adsorption areas of compounds were very large because of their high molecular weight. Moreover, PO compounds showed better properties than EO compounds in foamability, emulsifying power for organics (n-hexane, benzene), detergency for the lard, tallow oil mixture and dispersability for iron oxide. It was interpreted in terms of surface properties of the PO compounds. These showed that the interfacial activity become higher when hydrophilic and hydrophobic portion existed in aggoromerated state respectively. The test results of emulsifying power for organics (n-hexane, benzene) showed better for benzene than n-hexane. Eight kinds of sodium (EO, PO) dodecyl ether derivatives showed irregular dispersibilities for polar iron oxide in water dispersed media.

  • PDF

Experimental Study of Pool Boiling for Enhancing the Boiling Heat Transfer by Hydrophobic Dots on Silicon Surface (실리콘 표면 위에 소수성 점을 이용한 비등 열전달 증진에 관한 실험적 연구)

  • Jo, Hang-Jin;Kim, Hyung-Mo;Ahn, Ho-Seon;Kang, Soon-Ho;Kim, Joon-Won;Shin, Jeong-Seob;Kim, Moo-Hwan
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.34 no.6
    • /
    • pp.655-663
    • /
    • 2010
  • Wettability is important to enhance not only CHF but also nucleate boiling heat transfer, as shown by the results of different kinds of boiling experiments. In this regard, an excellent boiling performance (a high CHF and heat transfer performance) could be achieved in the case of pool boiling by some favorable surface modifications that can satisfy the optimized wettability condition. To determine the optimized boiling condition, we design special heaters to examine how two materials, which have different wettabilities (e.g., hydrophilic and hydrophobic materials), affect the boiling phenomena. The special heaters have hydrophobic dots on a hydrophilic surface. The contact angle of the hydrophobic surface is $120^{\circ}$ to water at the room temperature. The contact angle of the hydrophilic surface is $60^{\circ}$ at same conditions. Experiments involving micro hydrophobic dots and two types of milli hydrophobic dots are performed, and the results are compared with a reference surface.

Influence of Sulfur Fertilization on Quality Characteristics and Antioxidant Activities of Onions during Storage at 4℃ (유황처리가 4℃ 저장 중 양파의 품질 특성 및 항산화 활성에 미치는 영향)

  • Jo, Hyeri;Surh, Jeonghee
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.45 no.12
    • /
    • pp.1776-1783
    • /
    • 2016
  • Onions cultivated with (SY) or without (SN) sulfur application were stored for up to 36 weeks at $4^{\circ}C$ since harvest, after which they were analyzed for chemical composition and antioxidant activity in relation to sulfur (S) application and storage duration. Compared with SN onions, SY onions showed lower moisture and higher protein, soluble solids, and flavonoid contents at the time of harvest, and moisture and protein contents remained the same until 20 weeks of storage. However, soluble solids decreased while antioxidant activities, including flavonoids content, total reducing capacity, and superoxide dismutase (SOD)-like activity, appreciably increased as storage time increased to 20 weeks, which could be attributed to onion respiration and protective response to environmental stresses, respectively. There were abrupt decreases in flavonoid content and SOD-like activity at 36 weeks, presumably due to severe deterioration. Interestingly, all phenomena observed depending on storage time were independent of S application of onions. The results show that the critical factor influencing the chemical composition and antioxidant activity of onions during storage was postharvest storage duration rather than S application during onion cultivation.

Cytosolic prion protein induces apoptosis in human neuronal cell SH-SY5Y via mitochondrial disruption pathway

  • Wang, Xin;Dong, Chen-Fang;Shi, Qi;Shi, Song;Wang, Gui-Rong;Lei, Yan-Jun;Xu, Kun;An, Run;Chen, Jian-Ming;Jiang, Hui-Ying;Tian, Chan;Gao, Chen;Zhao, Yu-Jun;Han, Jun;Dong, Xiao-Ping
    • BMB Reports
    • /
    • v.42 no.7
    • /
    • pp.444-449
    • /
    • 2009
  • Different neurodegenerative disorders like prion disease, is caused by protein misfolding conformers. Reverse-transfected cytosolic prion protein (PrP) and PrP expressed in the cytosol have been shown to be neurotoxic. To investigate the possible mechanism of neurotoxicity due to accumulation of PrP in cytosol, a PrP mutant lacking the signal and GPI (CytoPrP) was introduced into the SH-SY5Y cell. MTT and trypan blue assays indicated that the viability of cells expressing CytoPrP was remarkably reduced after treatment of MG-132. Obvious apoptosis phenomena were detected in the cells accumulated with CytoPrP, including loss of mitochondrial transmembrane potential, increase of caspase-3 activity, more annexin V/PI-double positive-stained cells and reduced Bcl-2 level. Moreover, DNA fragmentation and TUNEL assays also revealed clear evidences of late apoptosis in the cells accumulated CytoPrP. These data suggest that the accumulation of CytoPrP in cytoplasm may trigger cell apoptosis, in which mitochondrial relative apoptosis pathway seems to play critical role.

Study on the Response of Korean Ginseng (Panax ginseng C.A. Meyer) to the Herbicide 2,4-D Application (고려인삼에 대한 제초제 2, 4-D의 반응연구)

  • Jo, Jae-Seong
    • Journal of Ginseng Research
    • /
    • v.14 no.2
    • /
    • pp.291-296
    • /
    • 1990
  • Various rates of 2,4-D were sprayed on 2 and 3 year old ginseng plants as foliar spray to define the critical concentration. No apparent plant injury was noticable for those ginseng plants when application concentration of 2,4-D doubled the recommended dosage (70 ml/10a). Neither abnormal foliar change occurred nor any inhibition in leaf and stem growth was resulted for the plants treated with 2,4-D concentrated two times of the recommended dosage. When the rates of 2,4-D application were increased greater than this level, injury ratings increased linearly with the rates of 2,4-D application and plant you was inhibited. Ethylene gas was not produced from the ginseng plant treated with 2 times concentrated 2,4-D, however the ginseng plants produced 0.03 to 0.09 ppm ethylene gas when the rate of application were increased 3 and 4 times, respectively. On the other hand the soybean treated with the recommended amount of 21-D produced ethylene gas of 10-20 times higher compared with ginseng plants and died. Photosynthesis ability of the ginseng leaf was significantly decreased by 2,4-D foliar application but it was recovered 4 weeks after 2,4-D foliar treatment. The herbicide 2,4-D was applicated to 2,3 and 4 years old ginseng plants as foliar spray with the rates of 0.5, 1.0, 1.5 and 2.0 times of the recommended dosage to define the effects of 2,4-D on the plant growth and root yield of the ginseng. There were no significant differences in the leaf and stem growth between untreated and 2,4-D treated plant. Berry maturing of 3 and 4 year old ginseng was not influenced by 2,4-D. The root weight of 4 years old ginseng plant was not reduced by application of 2,4-D concenrated 2 times of the recommended dosage, Application time of the herbicide 2,4-D had no effects on the leaf or stem growth of 2,3 and 4 year old year old ginseng plants. When the ginseng seedling was treated with 2,4-D, detrimental phenomena as stem bending and docoration of seedling leaf margin occurred, but stem bending was recovered in a few day s. Keywords Panax ginseng C.A. Meyer, 2,4-D , herbicide.

  • PDF