• Weed & Turfgrass Science
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• 제6권4호
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• pp.355-358
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• 2017

Amur silver grass, Miscanthus sacchariflorus is one of the promising biofuel weeds. A damage of noctuid pest, Leucapamea askoldis was firstly observed from Amur silver grass in Hwasun silver grass plantation during the survey of insect pests of Amur silver grass in Iksan, Hwasun, and Sancheong plantation areas in Korea. The host of L. askoldis was not known yet in Korea. The L. askoldis damage was observed as larval feeding on newly grown shoots and roots of M. sacchariflorus close to soil surface from early May in 2013. Investigated larval density was $1.6{\pm}1.1per\;m^2$ on April 4 and damage rate of shoots was $0.8{\pm}0.4%$ on May 4, 2013. The larvae bore into shoots of M. sacchariflorus and feed on the inside of plant. The damaged shoots are easily pulled out and distinguished by the boring hole on the shoots. L. askoldis was potential insect pest in M. sacchariflorus plantation areas.

• Parasites, Hosts and Diseases
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• 제54권4호
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• pp.543-547
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• 2016

In the present study, we report on the occurrence of paramphistomes, Fischoederius cobboldi and Paramphistomum epiclitum, in Lao PDR with the basis of molecular data. Parasite materials were collected from bovines bred in Ban Lahanam area, Savannakhet Province, Lao PDR at Lahanam public market. Morphological observations indicated 2 different species of paramphistomes. The mitochondrial gene cox1 of the specimens was successfully amplified by PCR and DNA sequencing was carried out for diagnosis of 11 specimens. Pairwise alignment of cox1 sequences were performed and confirmed F. cobboldi and P. epiclitum infecting bovines in Laos. Although there were many limiting points, as the small number of worm samples, and the restricted access of the animal host materials, we confirmed for the first time that 2 species of paramphistomes, F. cobboldi and P. epiclitum, are distributed in Lao PDR. More studies are needed to confirm the paramphistome species present in Savannakhet and its hosts to clear the natural history of these parasites of ruminants in the region and measure the impact of this parasite infection in the life and health of the local people.

• 한국결정성장학회지
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• 제29권6호
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• pp.245-250
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• 2019

라디오주파수 분말 스퍼터링 방법으로 sapphire (0001) 기판 위에 Sn을 함유한 β-Ga₂O₃(β-Ga₂O₃ : Sn) 나노와이어를 증착하였다. 후열처리 공정의 가스 분위기가 나노와이어 형상의 변화에 미치는 영향을 연구하였다. 800℃에서 진공 중 열처리 과정에서, as-grown 나노와이어는 다공성 구조로 전이하였다. 비화학양론 Ga₂O_3-x는 화학양론 Ga₂O₃로 바뀌고, Sn원자는 응집하여 나노클러스터를 형성한다. Sn 나노클러스터는 증발하여 Sn 원자의 함량은 1.31에서 0.27 at%로 감소하였다. Sn원자의 증발로 인하여 나노와이어 표면에 다수의 기공이 형성되고, 이는 β-Ga₂O₃ : Sn 나노와이어의 체적대비 표면적 비율을 증가시킨다.

• 대한바이러스학회지
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• 제28권3호
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• pp.225-232
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• 1998

We have expressed GFP in Sf9 and Bm5 cells or Bombyx mori larvae by using Ac-Bm hybrid virus capable of replicating in both Bm5 and Sf9 cells. Genomic DNA of Ac-Bm hybrid virus expressing ${\beta}$-galactosidase was cotransfected with baculovirus transfer vector containing GFP gene, pBacPAK-GFP in Sf9 cells. The Ac-Bm hybrid virus harboring GFP was named as Ac-Bm hybrid virus-GFP. The Ac-Bm hybrid virus-GFP-infected insect cells were easily selected by detecting the emission of GFP from each well of cell culture dish on the UV illuminator. GFP produced by Ac-Bm hybrid virus-GFP in Sf9 and Bm5 cells or B. mori larvae was confirmed by SDS-PAGE and Western blot analysis using GFP antibody. In addition, B. mori larvae infected with Ac-Bm hybrid virus-GFP was apparently appeared fluorescence from the whole body at S days postinoculation. The fluorescence of GFP from the hemolymph and fat body of B. mori larvae infected with Ac-Bm hybrid virus-GFP was also observed by fluorescence microscope. In conclusion, our results demonstrated that in baculovirus expression vector system, use of Ac-Bm hybrid virus have an additional advantage of expanded host range for producing recombinant proteins.

• 자원환경지질
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• 제37권2호
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• pp.225-234
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• 2004

춘궁동 오층석탑(보물 제12호)의 암석학적 풍화와 훼손도를 진단하였다. 이 석탑의 정면은 N30$^{\circ}$W를 향하고 있으며, 구성암석은 안구상 편마암과 흑운모 화강암이다. 석탑을 이루는 암석은 박리와 변색이 심하고, 조암광물은 화학적 및 광물학적 풍화에 의하여 점토광물로 변질되어 있다. 석탑의 표면과 부재사이에는 지의류와 이끼류의 모근 및 포자류가 기생하고 있으며, 하단부는 이미 고등식물이 천이하고 있다. 따라서 석탑의 표면에 피복된 지의류와 불연속면에 서식하고 있는 잡초를 제거하기 위한 생화학적 처리가 요구된다. 이 석탑의 구조적 안정을 위해서는 부재사이에 틈이 없도록 재조립을 해야 하며, 삽입한 철편도 제거한 후에 석조문화재 보강용 충전제를 이용한 보존처리가 필요하다. 또한 석탑에 미치는 지면의 습도를 저감하기 위한 차수층의 설치도 고려되어야 할 것이다.

• 한국표면공학회지
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• 제48권3호
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• pp.82-86
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• 2015

$Dy^{3+}$- and $Eu^{3+}$-codoped $CaMoO_4$ Phosphors were synthesized by using the solid-state reaction method. The crystal structure, morphology, and optical properties of the resulting phosphor particles were investigated by using the X-ray diffraction, field-emission scanning electron microscopy, and photoluminescence spectroscopy. XRD patterns exhibited that all the synthesized phosphors showed a tetragonal system with a main (112) diffraction peak, irrespective of the content of $Eu^{3+}$ ions. As the content of $Eu^{3+}$ ions increased, the grains showed a tendency to agglomerate. The excitation spectra of the synthesized powders were composed of one strong broad band centered at 305 nm in the range of 220 - 350 nm and several weak peaks in the range of 350 - 500 nm resulting from the 4f transitions of activator ions. Upon ultraviolet excitation at 305 nm, the yellow emission line due to the $^4F_{9/2}{\rightarrow}^6H_{13/2}$ transition of $Dy^{3+}$ ions and the main red emission spectrum resulting from the $^5D_0{\rightarrow}^7F_2$ transition of $Eu^{3+}$ ions were observed. With the increase of the content of $Eu^{3+}$, the intensity of the yellow emission band gradually decreased while that of the red emission increased. These results indicated that the emission intensities of yellow and red emissions could be modulated by changing the content of the $Dy^{3+}$ and $Eu^{3+}$ ions incorporated into the host crystal.

• 한국표면공학회지
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• 제49권1호
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• pp.81-86
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• 2016

$Eu^{3+}$-doped $MgMoO_4$ phosphor thin films were deposited on quartz substrates by radio frequency magnetron sputtering with changing various growth temperatures. The effects of growth temperature on the structure, transmittance, optical band gap, and luminescence of the phosphor thin films were characterized. All the phosphor thin films, irrespective of growth temperature, showed a monoclinic structure with a main (220) diffraction peak. The thin film deposited at a growth temperature of $400^{\circ}C$ indicated an average transmittance of 90% in the wavelength range of 500 ~ 1100 nm and band gap energy of 4.81 eV. The excitation spectra of the phosphor thin films consisted of a broad charge transfer band peaked at 284 nm in the range of 230 ~ 330 nm and two weak peaks located at 368 and 461 nm, respectively. The emission spectra under ultraviolet excitation at 284 nm exhibited a sharp emission peak at 614 nm and several weak bands. All the phosphor thin films showed high asymmetry ratio values, indicating that $Eu^{3+}$ ions incorporated into the host lattice occupied at the non-inversion symmetry sites. The results suggest that the growth temperature plays an important role in growing high-quality phosphor thin films.

• 한국전기전자재료학회논문지
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• 제24권6호
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• pp.486-490
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• 2011

To investigate the effect of two-emission-layer structure on the emission characteristics of the phosphorescent white organic light-emitting diodes (PHWOLEDs), the PHWOLEDs with two different emission layers, blue EML(29 nm, FIrpic-doped mCP) and red EML(1 nm, Ir(pq)$_2$acac-doped CBP)), following host-guest system were fabricated. The bi-layered blue EML was composed of mCP:FIrpic (20 nm, 7 vol.%) and mCP:FIrpic (9 nm, 7, 10, 15, 20, and 25 vol.%, respectively). When the concentration of FIrpic was increased from 7 to 15 vol.%, light emission luminance, current efficiency, and external quantum efficiency were increased. On the contrary, when the concentration of FIrpic was increased to more than 20 vol.%, light emission luminance, current efficiency, and external quantum efficiency were decreased. The PHWOLEDs with the bi-layered blue EML structure of mCP:FIrpic (20 nm, 7 vol.%) and mCP:FIrpic (9 nm, 15 vol.%) showed current efficiency of 29.7 cd/A and external quantum efficiency (EQE) of 16.6% at 1,000 $cd/cm^2$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.453-453
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• 2010

In this study, zinc germanate ($Zn_2GeO_4$) thin films has been synthesized by using radio frequency magnetron sputtering and the divalent manganese-activated luminescence was characterized. X-ray diffraction patterns of the as-deposited $Zn_2GeO_4$:Mn films showed only a broad feature, indicative of an amorphous structure. Scanning electron microscopy images revealed that the as-deposited $Zn_2GeO_4$:Mn has a smooth surface morphology. The $Zn_2GeO_4$:Mn films were found to be crystallized by annealing in air ambient at temperatures as low as $700^{\circ}C$. The annealed $Zn_2GeO_4$:Mn possessed a rhombohedral polycrystalline structure. The broad-band photoluminescent emission spectrum from 470 to 650nm was obtained at room temperature from the $Zn_2GeO_4$:Mn films. The emission peak was centered at around 535nm in the green range, which originates from the intrashell transition of manganese $3d^5$ electrons from $^4T_1$ excited-state level to the $^6A_1$ ground state. The PL emission spectrum had an asymmetric line shape, which results from the $^3d_5$ electron transitions of divalent manganese ions located at different sites of the zinc germanate host crystal lattice. Electroluminescent devices were fabricated using $Zn_2GeO_4$:Mn as an emission layer. The fabricated devices showed a green EL emission similar to the PL emission. The CIE chromaticity color coordinates of the EL emission were determined to be x=0.308 and y=0.657.

• 한국토양비료학회지
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• 제48권1호
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• pp.1-7
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• 2015

Global population is expected to reach nine billion in 2050 and the total demand for food is expected to increase approximately by 60 percent by 2050 as compared to 2005. Therefore, it is important to increase crop production in order to meet the global demand for food. Slow release fertilizers have been developed and designed in order to improve the efficiency of fertilizers. Mineral-based slow release fertilizers are useful because the minerals have a crystalline structure and are environmentally friendly in a soil. This review focuses on slow release fertilizers based on montmorillonite, zeolite, and layered double hydroxide phases as a host for nutrients, especially N. Urea was successfully stabilized in the interlayer space of montmorillonite by the formation of urea-Mg or Ca complex, $[(Urea)_6Mg\;or\;Ca]^{2+}$ protecting its rapid degradation in soils. Naturally occurring zeolites occluded with ammonium nitrate and potassium nitrate by molten salt treatment could be used as slow release fertilizer because the occlusion process increased the capacity of zeolites to store nutrients in addition to exchangeable cations. Additionally, surface-modified zeolites could also be used as slow release fertilizer because the modified surface showed high affinity for anionic nutrients such as nitrate and phosphate. Moreover, there were attempts to develop and use synthetic layered double hydroxide as a carrier of nitrate because it has positively charged layers which electrostatically bond nitrate anions. Kaolin was also tested by combining with a polymer or through the mechanical-chemical process for slow release of nutrients.