• 폴리머
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• 제25권6호
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• pp.826-832
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• 2001

본 연구에서는 폴리피를 (PPy)/gold/mylar 형태의 두 겹의 전기활성 구동기를 제작하였으며, 도판트의 종류에 따른 굽힘 구동 특성에 관한 연구를 수행하였다. 전도성 고분자는 전기적으로 산화/환원이 될 때에는 도판트의 이동에 의하여 부피 변화를 수반하게 된다. 도판트의 크기에 따라, 서로 다른 구동 특성을 나타내었는데, toluene sulfonate와 같은 작은 크기의 도판트는 산화/환원에 따라 PPy 필름의 내외로 자체 이동이 가능하며, 산화시에 PPy의 팽창이 관찰되었다. 그러나, dodecylbenzenesulfonate와 같은 커다란 도판트가 함유된 PPy는 산화/환원시에는 이들의 이온들은 움직임이 없는 것으로 나타났으며 환원시에 작은 양이온($Na^+$)이 필름내부로 유입되며 부피가 증가하는 현상이 관찰되었다.

• The Journal of Asian Finance, Economics and Business
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• 제5권4호
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• pp.173-185
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• 2018

At a turn of the third millennium the world storms and quickly changes. It became difficult to expect what expects us tomorrow. The most important are questions of recovery from the crisis and rescue of mankind from forthcoming global changes: warming of climate, water and food problems, social, economic and political conflicts that are shaking the world and other various cataclysms, accidents, negative processes. It puts before mankind the problem which never solved by our civilization. All this is caused by ignoring of objective economic laws, laws of wildlife and also by violation of cyclic development management's laws. In article the concept of strategy of mankind's survival in XXI and next centuries, the principles of creation of planetary house of universal civilization for post-industrial world based on spirituality scientific and technological revolutions, ecology, space exploration, economy and world safety are considered. Introduction of uniform universal measurement of currency for the whole world in the form of "power" is offered. Important aspect of a research is theoretical postulate on integrated innovative society. The author puts forward a new paradigm of government on a basis of 5 spirals. The basic model of forced development of small and medium business, including 9 projects, is developed.

• 한국수산과학회지
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• 제29권3호
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• pp.279-286
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• 1996

틸라피아를 해수에 순치하여 근육의 물성 및 식감을 개선하기 위하여 해수에 순치한 틸라피아를 $0^{\circ}C,\;10^{\circ}C$ 및 $20^{\circ}C$에 저장하면서 사후경직 중에 나타나는 근육의 물리적, 화학적 변화를 조사하였다. 사후경직은 $10^{\circ}C$와 $20^{\circ}C$ 에서보다 $0^{\circ}C$에서 빠르게 진행되었으며, 담수 사육한 것보다 해수 순치한 것이 경직개시 시간이 빨랐다. 사후경직 중 파괴강도와 사후 경직도와의 상관 관계는 없었으며, 파괴강도는 사후 12시간만에 최대로 되었고, 그 이후로는 육의 연화가 일어남으로 인하여 급격하게 저하된 반면에, 사후 경직도는 계속해서 증가하여 18시간 후에 최대치를 나타내었다. ATP 분해속도는 담수 사육어보다 해수 순치어에서 빨랐으며, 저장온도에 따른 분해속도는 $10^{\circ}C$와 $20^{\circ}C$에 비하여 $0^{\circ}C$에 저장한 시료에서 빠르게 나타났다. IMP 및 젖산은 저장온도가 낮을수록 축적속도가 빨랐고, 담수 사육어보다 해수 순치어에서 빠르게 나타났다. 이상의 결과로부터 담수어인 틸라피아를 해수에 순치시킴으로써 사후초기에 경직을 유도하고 근육의 물성을 변화시켜 식감을 증진시킬 수 있을 것으로 생각된다.

• Journal of Plant Biology
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• 제36권3호
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• pp.195-201
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• 1993

The room temperature fluorescence induction of chloroplasts was utilized as a probe to locate the site of inhibition by mercury, copper and zinc on PS II by mercury. Inhibitory effect of Hg2+ on electron transport activity was notable as compared with Cu2+ and Zn2+. At concentrations of HgCl2 over 50 $\mu$M, activities of PS II and whole-chain electron transport decreased more than 70%, while that of PS I decreased about 10~30%. This suggests that PS II is more susceptible to Hg2+ than PS I is. In the presence of diphenylcarbazide (DPC), 50 $\mu$M HgCl2 inhibited the reduction of dichlorophenolindophenol (DCPIP) about 50%. Addition of heavy metals induced marked decrease in maximal variable fluorescence/initial fluorescence [(Fv)m/Fo], but no changes in Fo. With various concentrations of heavy metals, changes of chlorophyll a fluorescence emitted by PS II showed gradual decrease in photochemical quenching (qQ), which indicates an increase in reduced state of electron acceptor, QA. Especially, the addition of HgCl2 caused a notable decrease of qQ. In the presence of 50 $\mu$M CuCl2, energy-depended quenching (qE) was completely reduced, whereas in the presence of 50 $\mu$M CuCl2 and ZnCl2 it was still remained. The above results are discussed on the effects of mercury in relation to water-splitting system and plastoquinone (PQ) shuttle system.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.973-976
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• 2006

The oscillations of the Caspian Sea level represent a result of mutually related hydrometeorological processes. The change in the tendency of the mean sea level variations that occurred in the middle 1970s, when the long-term level fall was replaced by its rapid and significant rise, represents an important indicator of the changes in the natural regime of the Caspian Sea. Therefore, sea level monitoring and long-term forecast of the sea level changes represent an extremely important task. The aim of this presentation is to show the experience of application of satellite altimetry methods to the investigation of seasonal and interannual variability of the sea level, wind speed and wave height, water dynamics, as well as of uplift of the Earth’s crust in different parts of the Caspian Sea and Kara-Bogaz-Gol Bay. Special attention is given to estimates of the Volga River runoff derived from satellite altimetry data. The work is based on the 1992-2005 TOPEX/Poseidon (T/P) and Jason-1 (J-1) data sets.

• 대한화학회지
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• 제7권1호
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• pp.1-5
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• 1963

The thermal decomposition process of ammonium paratungstate $5(NH_4)_2O{\cdot}12WO_3{\cdot}5H_2O$ was analysed by the methods of thermogravimetric analysis, differential thermal analysis, quantitative analysis of the ammonia which is released during heating and X-ray powder diffraction in air and in vacuo. There are several endothermic peaks which indicate release of ammonia and exothermic peaks which indicate crystal growth and oxidation of decomposed prodects in air. After water is driven off the ammonia is released at intervals corresponding to the endothermic peaks. The highest temperature at which ammonia is released is about $420^{\circ}C$ in air and $480^{\circ}C$ in vacuo. In air the crystal structure of paratungstate is conserved up to a temperature of $300^{\circ}C$ at which the remaining ammonia is about 4 mols. At $320^{\circ}C$ the remaining ammonia becomes less than 2 mols and the paratungstate structure changes into the amorphous state. After that ${\gamma}$ oxide is produced and is oxidized to ${\alpha}$ oxide in the temperature range of 400-$500^{\circ}C$ in air. In vacuo however the endothermic peaks and structural changes occur at lower temperatures and the structure of ${\gamma}$ oxide is conserved up to temperatures higher than $500^{\circ}C$.

• 한국해안해양공학회지
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• 제14권2호
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• pp.136-150
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• 2002

시화호의 수질을 개선할 목적으로 배수갑문을 통하여 외해수를 자유롭게 유통하는 방안이 고려되고 있다. 좁은 갑문을 통해 외해와 연결된 하구호는 갑문을 열고 닫는 것에 따라 희석 확산되고 상류 하천의 유입과 바람에 의해서 순환이 영향을 받는다. 이런 하구호의 수질예측목적으로 3타원 유한체적모형인 CE-QUAL-ICM을 3차원의 유한요소 동수역학모형인 TIDE3B와 연계 적응하였다. 서로 다른 두가지의 모형을 접합하여 이용할 때 발생될 수 있는 오차를 질량보존을 만족하면서 최소로 줄일 수 있는 방법을 제시하였다. 실제 관측치와의 비교검증을 통한 후 일년간 모델을 시험한 결과, 미 확정적인 초기조건의 영향을 받아 계산 초기의 60일간의 신뢰성은 의문시 되었다. 그러나 이후에는 부영양화 인자나 다른 수질 인자들이 준정상상태에 다다르는 결과를 보여 초기의 영향을 원만히 다를 수 있는 완화방안이 필요할 것으로 판단되었다. 수체와 저질사이의 반응도 모의하였지만 이 영향은 크지 않아 장기간의 모의에서는 저질의 영향을 고려하지 않아도 무난할 것으로 판단된다. 본 연구에서 새롭게 적용된 기법을 이용한 모의결과는 하구호의 수질개선을 위해 부영양화를 저감하는 것뿐만 아니라 능동적인 순환을 고려하는데 만족스럽게 응용될 수 있는 가능성을 보여주고 있다.

• Molecules and Cells
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• 제40권3호
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• pp.186-194
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• 2017

A brain-enriched secreting signal peptide, NELL2, has been suggested to play multiple roles in the development, survival, and activity of neurons in mammal. We investigated here a possible involvement of central NELL2 in regulating feeding behavior and metabolism. In situ hybridization and an immunohistochemical approach were used to determine expression of NELL2 as well as its colocalization with proopiomelanocortin (POMC) and neuropeptide Y (NPY) in the rat hypothalamus. To investigate the effect of NELL2 on feeding behavior, 2 nmole of antisense NELL2 oligodeoxynucleotide was administered into the lateral ventricle of adult male rat brains for 6 consecutive days, and changes in daily body weight, food, and water intake were monitored. Metabolic state-dependent NELL2 expression in the hypothalamus was tested in vivo using a fasting model. NELL2 was noticeably expressed in the hypothalamic nuclei controlling feeding behavior. Furthermore, all arcuatic POMC and NPY positive neurons produced NELL2. The NELL2 gene expression in the hypothalamus was up-regulated by fasting. However, NELL2 did not affect POMC and NPY gene expression in the hypothalamus. A blockade of NELL2 production in the hypothalamus led to a reduction in daily food intake, followed by a loss in body weight without a change in daily water intake in normal diet condition. NELL2 did not affect short-term hunger dependent appetite behavior. Our data suggests that hypothalamic NELL2 is associated with appetite behavior, and thus central NELL2 could be a new therapeutic target for obesity.

• 수산해양기술연구
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• 제52권3호
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• pp.197-208
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• 2016

The WCPFC CMMs related to tropical tunas have been strongly restricting fishing capacity and operating activities of main fisheries, especially purse seine fishery. In terms of changes in fishing trend by implementing relevant measures of FAD set, the number of FAD set by Korean purse seine fleet showed a decreasing pattern with the lowest level of FAD set proportion among major distant water fishing nations. With regards to the FAD closure, there was no significant change in fishing effort but a drop in catch, especially bigeye tuna during the period of FAD closure. Moreover, it showed closely similar trends between the number of FAD set and bigeye tuna catch. In terms of measures related to the high sea area including a ban on fishing on the HSP and limitation of fishing days on the high sea by flag state, proportions of catch and effort on the high sea had sharply declined after implementing those measures. As relevant measures are expected to be strengthened, it should pay attention to change of coastal nations policies and focus on improving fishing efficiency of unassociated school set with multi-pronged efforts.

• 한국환경과학회지
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• 제1권1호
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• pp.77-88
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• 1992

Distribution patterns of the chemical species, contained or dissolved in the sediments and porewater, were studied from the submarine environments around Deok-Jeok Island, Yellow Sea. The sediments in the study area are predominantly composed of medium to coarse sands, and consequently of very low organic carbon (0.003%) -0.26%o dry weight sediments). As opposed to the strong enrichment of porewater with nutrients and heavy metals in the ordinarily muddy, organic-rich sediillents, the porewater enrichment is not intense in this sandy, organic-poor sediments: porewater phosphate is enriched to the maximum of only seven (average two) times over that in the bottom water. Concentrations of the heavy metals dissolved in porewater show a bit greater enrichment than the nutrient: Zn shows the lowest enrichment (7 times that of the bottom water) and Mn the highest (450 times that of the bottom water). However, these enrichments of the chemical species in porewater are the natural consequences of decomposition of the organic matter in sediments, and still fall short in the magnitude of those in the muddy, organic-rich sediments. Mining of the sands in the study area may pose a threat to the seawater quality as it causes a large scale porewater discharge to the bottom water. The additional supply of the nutrients by this discharge may develop an eutrophic state and, in consequence, an excessive nitrification of the water column. Since the residence times of the nutrients are much longer than those of the heavy metals, a long-term monitoring of the concentration changes in the porewater nutrients is very important to assess the potential deterioration of the seawater associated with the sand mining in the study area.