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An Analysis of Biotope Structure in Metropolitan city in terms of Nature Experience and Recreation (대도시의 비오톱 구조분석 -자연체험 및 휴양의 관점에서-)

  • 나정화;이석철
    • Journal of the Korean Institute of Landscape Architecture
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    • v.28 no.3
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    • pp.72-87
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    • 2000
  • The purpose of this research was analysis of biotope structure focused on the evaluation for the nature experience and recreation in the case of Suseoung District in Daegu metropolitan area. The results of this study were as follows; 1) The result of biotope type classification was divided into 17 biotope type groups and 90 biotope types belonging to them. 2) In the result of the first evaluation for the nature experience and recreation, biotope types such as MA, NA, OE, PH, QB etc. possess great value. Particulary these biotope types come from forest areas and transition zone. The have not appeared in the inner of cities. 3) The biotope types such as JC, ME, OA, OE, PB, QD, QF etc. are proved to possess high value in the result of the utility evaluation. 4) There emerges 3a biotope type that has the highest value in the result of the second evaluation - such as ME, NB, NC, PD, QB etc. Most of them range widely except in the urbanized areas. Most of them were presented into the large area of site size and in the outer forest areas. But most of them were distributed in the forest areas intensively. So, it is certain that the space of nature experience connected with residential district of the urban people s scarce. Finally, the detailed plan must be made out specially continuously. It is about biotope spaces that are important for the nature experience and the recreation from the result of this research. Also, the study on the detailed index settlement of the sight green plan based on the biotope map must be continued.

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A study on Fabrication of Ferroelectric SST Thin Films by Liquid Delivery MOCVD Process (Liquid Delivery MOCVD공정을 이용한 강유전체 SBT 박막의 제조기술에 관한 연구)

  • Kang, Dong-Kyun;Paik, Seung-Kyu;Kim, Hyoeng-Ki;Kim, Byong-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05c
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    • pp.111-115
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    • 2003
  • 200nm 정도의 두께를 가진 SBT 박막이 liquid delivery MOCVD 공정에 의해 (111) oriented Pt/Ti/$SiO_2$/Si 기판 위에 증착되었다 이 실험에서는 $Sr(TMHD)_2$tetraglyme, $Bi(ph)_3$ 그리고 $Ta(O^iPr)_4$(TMHD)를 출발 물질로 사용하였다. Sr 출발 물질의 열적 안정화를 위해서 adduct로 tetraglyme를 사용하여 실험하였고 유기 용매로는 n-butyl acetate를 사용하였다 Substrate temperature와 reactor pressure는 각각 $570^{\circ}C$와 5Torr로 유지시켰다. 또한 vaporizer의 용도는 $190-200^{\circ}C$, 그리고 delivery line 의 온도는 vaporizer 보다 높게 유지 $(220-230^{\circ}C)$하여 출발 용액을 분당 0.1ml로 50분간 주입하였다. 수송가스로 Ar, 산화제로 $O_2$ 가스를 사용하였다. 제조한 SBT 박막은 $750^{\circ}C$에서 열처리한 후 인가전압 3V와 5V에서 $2P_r$값이 각각 6.47, $8.98{\mu}C/cm^2$이었으며, $2E_c$값은 인가전압 3V와 5V에서 각각 2.05, 2.31V이었다 그리고 $800^{\circ}C$에서는$750^{\circ}C$에서 열처리한 SBT 박막보다 다소 우수한 이력특성을 나타내어 $2P_r$ 값은 인가전압 3V와 5V에서 각각 7.59, $10.18{\mu}C/cm^2$ 이었으며, $2E_c$값은 인가 전압 3V와 5V에서 각각 2.00, 2.21V 이었다.

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A Study on the Current-Voltage Characteristics of Self-Assembled Nitro-group and Methoxy-group Organic Molecules by Using STM (STM을 이용한 자기조립된 니트로기와 메톡시기 유기분자의 전압-전류 특성 연구)

  • Kim, Seung-Un;Park, Sang-Hyun;Park, Jae-Chul;Shin, Hoon-Kyu;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2004.11a
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    • pp.212-214
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    • 2004
  • In this study, we fabricated the organic thin film by self-assembly method by using nitro-group and methoxy-group organic molecule. Also, we selected the organic single molecule in organic thin film and measured current-voltage characteristics by using scanning tunneling microscopy. The Organic molecules that use in an experiment is 4,4'-(diethynylphenyl)-2'-nitro-1-benzen ethiol and 4-[2,5-dimethoxy-4-ph enylethynylphenyl]ethynylphenylethanthiol. 4,4'-(dimet hynylphenyl)-2'-nitro-1-benzenethiol is applied widely in molecular electronic device and 4-[2,5-dime thoxy-4-phenylethynylphenyl]ethynylphenylethanthiol composed in Korea Research Institute of Chemical Technology. To be confirmed the formation of the self-assembled monolayers, we observed the real time frequency shift of the QCM and investigated surface of the self-assembled monolayers the using STM. With this, we measured current to the organic single molecule, in condition of the air state. As a result, we confirmed in constant voltage that properties of negative differential resistance. Using properties of negative differential resistance to get from this study, application is expected to be molecular switching device, memory device and logic device.

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Influence of Heating, Cooling and Acidity on the Permeability of the Rabbit Erythrocyte Membrane (고온, 한냉 및 산도가 토끼 적혈구막 투과성에 미치는 영향)

  • Lee, D.S.;Shin, H.S.;Hwang, E.R.;Choi, D.K.
    • The Korean Journal of Physiology
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    • v.1 no.2
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    • pp.151-156
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    • 1967
  • Outward movement of hemoglobin and $K^+$ ion across rabbit erythrocyte membrane after heating, cooling and in acid medium was studied. One milliliter of rabbit blood was centrifuged and packed red cells were obtained. Packed red cells were resuspended by addition of 4 ml of 0.9% NaCl solution and were subjected to heating $(57^{\circ}C\;for\;5\;minutes)$ or cooling $(-4^{\circ}C{\sim}-8^{\circ}C\;of\;-10^{\circ}C{\sim}-11^{\circ}C\;for\;10\;minutes) $. For acid medium experiment packed ref cells were resuspended by addition of 4 ml of acid medium of PH 4.5 consisting of 0.01% glacial acetic acid in 0.85% NaCl solution and kept standing for 10 minutes. All red cell suspensions were centrifuged again and packed red cells were separated. This packed red cells were again suspended in 4 ml of NaCl solution of 0.8%, 0.7%, 0.6%, and 0.5% concentration respectively and kept standing for 20 minutes. The concentration of hemoglobin and $K^+$ in the supernatant of the above red cell suspensions were measured and the following results were obtained. 1. Outward movement of hemoglobin and $K^+$ was greatest in red cells subjected to heating. The movement paralled to the osmolal concentration gradient between extra- and intra-cellular phase of red cells. 2. In acid medium the outflux of hemoglobin and $K^+$ increased as compared to the control. 3. In red cells subjected to the cold of $-10^{\circ}C{\sim}-11^{\circ}C$ the outflux of hemoglobin and $K^+$ increased. Whereas in the environment of $-4^{\circ}C{\sim}-8^{\circ}C$ there was no change in the outflux of $K^+$. The he-moglobin outflux showed rather a decreased as compared to tile control.

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Drug-Biomacromolecule Interaction (XIII)-Effect of ionic Strength, pH and Temperature on Binding of Cephalothin to Bovine Serum Albumin- (약물과 생체고분자 간의 상호작용(제 13보)-세파로친과 소혈청알부민의 결합에 미치는 이온강도, pH 및 온도의 영향)

  • Kim, Chong-Kook;Lim, Yun-Su;Yang, Ji-Sun;Jeong, Eun-Ju
    • Journal of Pharmaceutical Investigation
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    • v.19 no.3
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    • pp.163-171
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    • 1989
  • To investigate the protein binding characteristics of cephalothin, the effects of ionic strength, pH and temperature on the binding of cephalothin to bovine serum albumin (BSA) were studied by UV difference spectrophotometric method. With increasing ionic strength at constant PH and temperature, association constant decreased, but the number of binding sites sites was about 2 constantly. It may be deduced that the binding process is not only due to electrostatic forces. And the increased association constant at high ionic strength is explained by conformational changes of BSA from complex to subunits. The pH effect on the affinity of interaction indicated that the binding affinity of drug is higher in the neutral region than in the alkaline region. And, at high pH value, the number of binding sites decreased from 2 to 1 because of the conformational changes of BSA in alkaline region. The decrease in binding affinity of BSA to drug with increasing temperature was characteristic of an exothermic reaction. And the negative sign of ${\Delta}G^{\circ}$ meant that the binding process occurs spontaneously under the experimental conditions. In cephalothin-BSA complex formation, since the net enthalpy change value and entropy change value are positive, it is assumed that hydrophobic bindings are predominant in this binding process.

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Studies on the L-Glutamic acid Fermentation(Part II) L-Glutamic acid Production Employing Enzymatic Hydrolyzate of Tapioca Pellets as Carbon Source (L_Glutamic acid 발효생산에 관한 연구 (제이보) Tapioca Pellets 효소 당화액을 이용한 L_Glutamic acid 생산)

  • Yang, Han-Chul;Park, Yong-Jin;Kim, Jea-Weon
    • Microbiology and Biotechnology Letters
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    • v.3 no.3
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    • pp.147-156
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    • 1975
  • The possibility of using tapioca pellets as a raw material in glutanmic acid fermentation by Microcuccus glutamicus is shown. The ground pellets were diluted with water to 20% solid level and treated with $\alpha$-anylase prepared from a thermophilic Actinomycetes strain culture for 90 min at 85$^{\circ}C$ under pH 6.0. The liquefied solution was further saccharified with commercial glucoamylase for 36 hours under the reaction conditions of 55$^{\circ}C$ and pH 5.0. The inhibitory effect of excess biotin content, 16 $\mu\textrm{g}$ Per liter of the hydrolzate, could be reduced effectively by adding 10 IU of penicillin per ml of the medium after five hours of the fermentation. The maximum glutamic acid yield of 38.5 g/l was obtained after 60 hours of shaking culture at 28-3$0^{\circ}C$.

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Adsorption Studies of Nickel(II) Ions onto Amorphous Alumina (무정형 알루미나에서의 니켈(II) 이온의 흡착에 관한 연구)

  • Park, Yeong Jae;Suh, Moo Yul;Park, Kyoung Kyun;Choi, Kwang Soon;Jee, Kwang Yong;Kim, Won Ho
    • Analytical Science and Technology
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    • v.13 no.4
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    • pp.433-439
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    • 2000
  • Adsorption behaviors of Ni(II) ions were investigated using amorphous alumina as adsorbent. In the adsorption kinetic study, it was observed that Ni(II) ions were bound to the alumina surface in two adsorption stages, the rapid and slow adsorption stages. The rapid adsorption proceeded within 1 hr, thereafter the slow adsorption occurred. The results of adsorption isotherm experiments showed that the Ni(II) adsorption obeyed the Langmuir-Freundlich isotherm, and that the adsorption enhanced with increasing pH. The change in ionic strength did not exhibit a conspicuous trend in Ni(II) adsorption, thereby suggesting that the adsorption occurs through surface complexation rather than electrostatic interactions. The amounts of adsorption were measured with varying pH at three different Ni(II) concentrations under the condition of constant ionic strength, showing that with increasing Ni(II) concentration, the percentage of adsorption decreased and the adsorption edge was shifted to a higher pH value.

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Kinetics and hydrolysis mechanism of insecticide O,O-diethyl-O-(1-phenyl-3-trifluoromethylpyrazol-5-yl)phosphorothioate (Flupyrazofos) (살충제 O,O-diethyl-O-(1-phenyl-3-trifluoromethylpyrazol-5-yl)-phosphorothioate(Flupyrazofos)의 가수분해 반응 메커니즘)

  • Sung, Nack-Do
    • The Korean Journal of Pesticide Science
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    • v.6 no.3
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    • pp.218-223
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    • 2002
  • The rate of hydrolysis of insecticide, O,O-diethyl-O-(1-phenyl-3-trifluoromethylpyrazol-5-yl)phosphorothioate (Flupyrazofos) have been investigated in 25% (v/v) aqueous dioxane (${\mu}=0.1M$) at $45^{\circ}C$. The hydrolysis mechanism of flupyrazofos proceeds through the specific acid ($A_{AC}2$) catalysis below pH 4.0, specific base ($B_{AC}2$) catalysis above pH 11.0 and general acid & base ($B_{AC}2$) catalysis between pH 5.0 and pH 10.0 via trigonal-bipyramidal ($d^2sp^3$) intermediate as evidence by solvent effect ($|m|{\ll}|{\ell}|$), rate equation ($kt=ko+k_H+ [H_3O^+]+k_{OH}[OH^-]$) and product analysis. The half-life ($T\frac{1}{2}$) of hydrolytic degradation in neutral media at $45^{\circ}C$ was ca. 3 months.

Investigation of Reclamation for Waste $CO_2$ Mold Sand of Steel Foundries in Busan and Gyeong Area (부산 ${\cdot}$ 경남지역 주강 공장의 $CO_2$ 주형 고사의 발생실태와 재생에 관한 연구)

  • Choi, Jun-Oh;Kim, Min-Seop;Choi, In-Seok;Cheon, Byung-Wook;Choi, Chang-Ock
    • Journal of Korea Foundry Society
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    • v.22 no.3
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    • pp.121-129
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    • 2002
  • According to the investigation of waste $CO_2$ molding sand in the 15 steel foundries in Busan and Gyeong area, about 1 ton of waste $CO_2$ molding sand per ton of steel castings production was produced In order to reduce amount of $Na_2O$, Loss of Boiling (L.O.B), Loss of Ignition (L.O.I), Conductivity and PH which are present in the waste $CO_2$ molding sand below the reclamation effect, more than 50% of elimination for reclamation was required. It was found that the waste $CO_2$ molding sand does not contain a harmful component designated by industrial waste materials. Reclamation of the waste $CO_2$ molding sand was practically achieved by an abrasive-dry reclamation process. According to bench time of the sodium silicate-bonded $CO_2$ molding sand, reduction of compressive strength and surface stability index(S.S.I) become slowdown. Therefore, the reclaimed sand could be allowed the reuse of molding sand in $CO_2$ molding process including core sand.

Flavor Components of Barley Meju manufactured with barley bran (보리등겨로 제조한 메주의 향기성분)

  • Choi, Ung-Kyu;Son, Dong-Hwa;Kwon, O-Jun;Lee, Eun-Joung;Kwak, Dong-Ju;Gwon, O-Jin;Chung, Yung-Gun
    • Applied Biological Chemistry
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    • v.43 no.3
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    • pp.196-201
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    • 2000
  • This study was conducted to investigate various flavor components of barley meju during fermentation. The change of PH was $5.2{\sim}5.6$. L-value and b-value gradually decreased. a-value gradually increased until fifth day and then decreased. Among 75 flavor compounds identified in barley meju, 10 aldehydes and 10 ketones were most in number followed by 9 acids, 9 phenols, 7 hydrocarbons, 7 alcohols and 6 esters. The contents of ethyl acetate $(67.8{\sim}89.1%)$ was more than those of any ether component followed by hexadecanoic acid $(1.21{\sim}12.00%)$ and tetramethylpyrazine $(0.06{\sim}12.30%$).

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