• 한국습지학회지
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• 제13권2호
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• pp.199-208
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• 2011

세계적으로 물의 부족, 온실가스 배출증가, 에너지 소비 증가 등으로 인하여 지구가 위협받고 있다. 기존의 도시 계획 및 개발 과정에서 산림, 하천 등 자연 생태계가 파괴되어 왔으며 이는 불투수면의 증가를 초래하였다. 불투수면의 증가로 인하여 자연적인 물순환 체계가 파괴됨에 따라 도시내 물의 저류, 침투, 증발 등이 감소되고 있으며, 강우시 불투수면에서 발생하는 비점오염원이 하천 및 호소로 직접 유입되어 수계에 악영향을 끼치고 있는 실정이다. 본 연구에서는 강우시 불투수면에서 발생하는 비점오염물질을 저감하고 불투수면의 증가로 인한 도시지역의 온도증가, 열섬현상 등을 해결하는 소규모 HSSF 인공습지 기술을 개발하고자 한다. HSSF 인공습지는 표면에 물이 존재하지 않고 유체의 흐름이 표면 아래 수평으로 흐르는 습지이며 침전, 여과, 흡착, 식생에 의한 흡수 등의 기작을 포함한다. 이러한 HSSF 인공습지를 도시지역의 협소한 공간에도 적용이 가능한 소규모 형태로 개발하고자 pilot-scale test를 실시하였으며, 이러한 연구결과는 향후 국내 도시 열섬현상 저감 및 자연적 물순환 복원을 위한 시설 개발에 기초자료로 활용 될 것이다.

• 한국진공학회지
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• 제18권6호
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• pp.459-467
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• 2009

진공증착법으로 $Cd_2GeSe_4$와 $Cd_2GeSe_4:Co^{2+}$ 박막을 ITO(indium tin oxide) 유리 기판 위에 제작하였다. 결정화는 증착된 박막들을 질소분위기의 전기로에서 열처리함으로서 이룰 수 있었다. X-선 회절 분석에 의하여 증착된 $Cd_2GeSe_4$와 $Cd_2GeSe_4:Co^{2+}$ 박막의 격자상수는 $a\;=\;7.405\;{\AA}$, $c\;=\;36.240\;{\AA}$와 $a\;=\;7.43\;{\AA}$, $c\;=\;36.81\;{\AA}$로서 능면체(rhombohedral) 구조이었고, 열처리 온도를 증가함에 따라 (113)방향으로 선택적으로 성장됨을 알 수 있었다. 열처리 온도를 증가시킴에 따라 입계 크기가 점차 커지고 판상구조로 결정화 되었다. 실온에서 측정한 광학적인 에너지 띠 간격은 열처리 온도의 증가에 따라 $Cd_2GeSe_4$ 박막의 경우 1.70 eV ~ 1.74 eV로 증가하였고, $Cd_2GeSe_4:Co^{2+}$ 박막의 경우 1.79 eV ~ 1.74 eV로 감소하였다. $Cd_2GeSe_4$와 $Cd_2GeSe_4:Co^{2+}$ 박막 내의 전하운반자들의 동역학적 거동을 광유기 방전 특성(PIDC : photoinduced discharge characteristics) 방법으로 조사하였다.

• 센서학회지
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• 제7권1호
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• pp.67-72
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• 1998

Plused ArF excimer laser ablation과 열증착법에 의해 p형 Si 기판위에 PbTe/CuPc 박막을 증착하였다. 성장된 박막의 구조적, 전기적 특성은 XRD, 전류-전압 곡선등의 분석으로 행하였다. XRD 분석으로부터 PbTe박막과 CuPc 박막은 a 축의 배향성을 지닌 박막으로 성장하였음을 알 수 있었다. PbTe/CuPc/Si 박막의 광전특공을 조사하기 위하여 빛을 조사했을 때와 빛을 조사하지 않았을 때의 수직방향의 전류-전압 (I-V) 특성을 CuPc/Si, PbTe/Si 단층막의 특성과 비교 관찰하였다. PbTe/CuPc/Si 박막에서 단축 광전류 ($J_{sc}$)가 $25.46\;mA/cm^{2}$, 개회로 광전압 ($V_{oc}$)이 170 mV인 커다란 광기전력 특성을 나타내었다. 또한 양자효율 (QE)은 15 %, 광전변환효율 (${\eta}$)은 $3.46{\times}10^{-2}$로 측정되었다. QE와 ${\eta}$를 기초로 한 PbTe/CuPc/Si 접합과 광전류 과정은 CuPc 층에서의 광캐리어 생성, PbTe/CuPc 계면에 의 광캐리어 분리 그리고 PbTe층에서의 광캐리어 운송 역할이 효율적으로 수행된 결과임을 알 수 있었다.

• 한국어류학회지
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• 제23권1호
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• pp.70-74
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• 2011

논에 서식하는 미꾸라지는 겨울철 수분증발에 의한 토굴을 형성하였고 피부는 공기 중에 노출되었다. 이때 미꾸라지 피부의 점액세포 변화를 유발하는 환경요인을 분석하기 위하여 진흙과 물을 수조에 채운 후 약 1개월 동안 자연증발시켜 인위적인 토굴형성에 의한 미꾸라지 피부의 공기노출 실험을 여름철에 실시하였다. 그 결과, 공기 중에 피부가 노출된 미꾸라지의 등, 체측, 후두부의 피부 점액세포의 형태는 대부분 크고 길다란 원주세포형으로 변화하였고, 수량 역시 급격히 증가하였는데, 이러한 특정은 겨울철 자연상태에서 나타나는 전형적인 현상이었다.

• 한국유체기계학회 논문집
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• 제5권1호
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• pp.49-54
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• 2002

HANARO, 30 MW of research reactor, was installed at the depth of 13m in an open pool. The $90\%$ of primary coolant was designed to pass through the core and to remove the reaction heat of the cote. The rest, $10\%$, of the primary coolant was designed to bypass the core. And the reactor coolant through and bypass the core was inhaled at the top of chimney by the coolant pump to prevent the radiated gas from being lifted to the top of reactor pool. But, the part of core bypass coolant was not inhaled by the reactor coolant pump and reached at the top of reactor pool by natural convection, and increased the radiation lovel on the top of reactor pool. To reduce the radiation level by protecting the natural convection of the core bypass flow, the hot water layer (HWL, hereinafter) was installed with the depth of 1.2 m from the top of reactor pool. As the HWL was normally operated, the radiation level was reduced to five percent ($5\%$) in comparing with that before the installation of the HWL. When HANARO was operated at a higher temperature than the normal temperature of the HWL by operating the standby heater, it was found that the radiation level was more reduced than that before operation. To verify the reason, the heat loss of the HWL was calculated by Visual Basic Program. It was confirmed through the results that the larger the temperature difference between the HWL and reactor hall was, the more the evaporation loss increased. And it was verified that the radiation level above was reduced mote safely by increasing the capacity of heater.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.221-226
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• 2001

HANARO, 30MW of research reactor, was installed at the depth of 13m of open pool, The $90\%$ of primary coolant was designed to pass through the core and to remove the reaction heat of the core. The rest $10\%$, of the primary coolant was designed to bypass the core. And the reactor coolant through and bypass the core was inhaled at the top of chimney by the coolant pump to protect that the radiated gas was lifted to the top of reactor pool. But, the part of core bypass coolant was not inhaled by the reactor coolant pump and reached at the top of reactor pool by natural convection and increased the radiation level on the top of reactor pool. To reduce the radiation level by protecting the natural convection of the core bypass flow, the hot water layer (HWL, hereinafter) was installed with the depth of 1.2m from the top of reactor pool. As the HWL was normally operated, the radiation level was reduced to five percent ($5\%$) in comparing with that before the installation of the HWL. When HANARO was operated with higher temperature than the normal temperature of the HWL by operating the standby heater, it was found that the radiation level was more reduced than that before operation. To verify the reason, the heat loss of the HWL was calculated. It was confirmed through the results that the larger the temperature difference between the HWL and reactor hall was, the more the evaporation loss was increased. And it was verified that the radiation level above was reduced more safely by increasing the capacity of heater.

• 분석과학
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• 제8권4호
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• pp.759-770
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• 1995

By extensive studies with the quantitative status of the mineral constituents of thousands of water samples, it was found that almost in all natural waters irrespective of the surface or sub-surface sources, minimum 99.5% of the total amount of the cationic constituents are generally the contributions of 3 commonly present parameters viz. Ca, Mg and Na and that of the anionic species are same and contributed by $HCO_3$, Cl and $SO_4$ only. In the field of water works, all these major mineral substances are conventionally measured as their individual ions. But till now, no reliable and generalised methods or rules have been developed for the determination of the exact kinds of the individual salt components and their amounts from these ionic constituents normally present in water. As salt content, only the TDS (Total Dissolved Solids) parameter is frequently measured by evaporation of the water sample. But TDS can tell nothing about the kinds and amounts of the individual salts present in it. Considering the analytical importance of the estimation of the mineral substances as their individual salts, some generalised mathematical models have been developed by this research which are based on the 'hypothetical order of chemical combinations' as may occur among the ionic constituents. With the help of these models, one can easily assume the most probable salts with approximate quantities derived from the ionic constituents. In addition, approximate amount of Na content can also be estimated mathematically with simultaneous verification of the correctness of the water analysis results. The models are stated in this paper with practical illustrations and descriptions of the method of applications.

• 대한환경공학회지
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• 제39권2호
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• pp.59-65
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• 2017

본 연구에서는 식품과 화장품 재료로 다양하게 이용되는 천연다당류의 특성인 분자구조, 분자량, 점성, 친수성, 팽윤 및 습윤/보습 등을 이용하여 $PM_{10}$에 대한 먼지 억제제를 제조하였고 Lab과 Field Test를 통하여 다양한 먼지 제어 효과를 확인하였으며 대조군인 물에 의한 단순 살수와 합성 PVA보다 우수한 결과를 도출하였다. 또한, 수분 증발 비교, 배추씨 발아와 배추 생장 비교실험(Pot Test), 물고기와 수생식물에 대한 영향 및 허브 식물 성장에 대한 영향 등의 토양 및 수질 시험 등을 통하여 토양과 수질에서의 안전성 등을 연구하여 Polysaccharides를 이용한 $PM_{10}$ 먼지 억제제의 이용 가능성을 확인할 수 있었다.

• 통합자연과학논문집
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• 제9권2호
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• pp.94-102
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• 2016

The crystal structure of the potential active 6-ethoxy-3-phenyl-5a,9a-dihydro-3H-chromen[4,3-c][1,2]oxazole-3a(4H)-carbonitrile ($C_{19}H_{15}N_2O_3$) has been determined from single crystal X-ray diffraction technique. The title compound crystallizes in the monoclinic space group C2/c with unit cell dimension a= 29.3026(9) ${\AA}$, b= 6.7695(2) ${\AA}$ and c= 19.7597(6) ${\AA}$ [${\alpha}= 90^{\circ}$, ${\beta}= 125.709(10)^{\circ}$ and ${\gamma}= 90^{\circ}$]. Single crystals suitable for X-ray diffraction were obtained by slow evaporation method, the isoxazole and six membered pyran rings adopts envelope conformation. The crystal packing of the molecules is stabilized by the weak $C-H{\ldots}N$ hydrogen bond interaction.

• 통합자연과학논문집
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• 제9권2호
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• pp.103-112
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• 2016

The crystal structure of the potential active Methyl 8-bromo-3-phenyl-5a,9a-dihydro-3H-chromen [4,3-c][1,2] isoxazole-3a(4H)-carboxylate ($C_{18}H_{15}BrNO_4$) has been determined from single crystal X-ray diffraction technique. The title compound crystallizes in the triclinic space group Pī with unit cell dimension a=8.3129 (3) ${\AA}$, b=9.5847 (4) ${\AA}$ and c=11.1463(4) ${\AA}$ [${\alpha}=98.457(3)^{\circ}$, ${\beta}=102.806(2)^{\circ}$ and ${\gamma}=105.033(5)^{\circ}$]. Single crystals suitable for X-ray diffraction were obtained by slow evaporation method, the isoxazole and six membered pyran rings adopts envelope conformation. In the crystal, molecules are linked via pairs of inter molecular $C-H{\ldots}O$ hydrogen bonds to form dimmers.