• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.1-9
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• 1990

This experiment was carried out to understand the effect of pre-sowing seed treatment by GA$_3$ and IAA on flowering and characteristics of yield component in peanuts. Peanut seed was treated by soaking in 10, 50, 100ppm of GA$_3$ solution, and 50, 100, 200ppm of IAA solution. Treatments of GA$_3$ and IAA resulted 7-5 days earlier emergence and 11-17days shorter of the flowering date compared with the untreated control. By soaking treatments with IAA in 100ppm and GA$_3$ in 100ppm, accumulated flowers were increased at early growing stage of 30 days after flowering compared with untreated control. By soaking treatments with IAA in 100ppm and GA$_3$ in 100ppm, main stem length, branch length and internode of main stem showed to flourish at investigation from early growing stage to 3 days before harvesting.

• Korean Journal of Medicinal Crop Science
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• v.8 no.4
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• pp.319-326
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• 2000

This experiment was carried out to determine the effects of $GA_3$ treatment (concentration: period) to rhizomes before planting on their growth, morphology and yield. $GA_3$ treatment increased the number of shoots, leaves or latent buds, plant height, and leaf length per plant compared with non-treatment. The best treatment concentrations were 50 ppm in stem per plant, 100 ppm in latent bud and rhizome fresh weight per plant and 250 ppm in shoot fresh weight per plant. The number of leaves and roots per plant, plant height and fresh weights of shoot and root were the greatest in one day imbibition of $GA_3$. Numbers of stems and latent buds per plant and rhizome fresh weight, however, were the highest in two day imbibition. In addition, the most rhizomes per land unit were produced in one day imbibition treatment of 100 ppm $GA_3$.

• New Physics: Sae Mulli
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• v.68 no.12
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• pp.1308-1314
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• 2018

$Er^{3+}$ and $Yb^{3+}$ co-doped $Y_3Ga_5O_{12}$ polycrystalline powders were prepared by using a solid-state reaction method, and their crystallinities were measured using X-ray diffraction. According to the results of X-ray diffraction, the powders showed a polycrystalline tetragonal structure. The photoluminescence and the upconversion luminescence properties of the $(Y_{0.85-x}Yb_{0.15})_3Ga_5O_{12}:Er^{3+}_x$ (x = 0.03, 0.06, 0.09, 0.12 and 0.15) phosphors were investigated in detail. Green and red upconversion emissions were observed for the phosphors excited by 980 nm radiation from a semiconductor laser. The powders exhibited strong green and weak red upconversion emission peaks at 553 and 660 nm, respectively. Also, their upconversion processes were explained using an energy-diagram analysis and the strongest upconversion intensity was emitted by the powder with a 0.12 mol $Er^{3+}$ ion concentration.

• Journal of Life Science
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• v.13 no.2
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• pp.137-142
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• 2003

The present experiment was done to determine the effect of priming, $GA_3$ and prechilling treatment alone and in their combination on germination of gourd (Lagenaria siceraria Standl.) seeds. Priming using $KNO_3$ and $GA_3$ were treated with different concentrations and periods whereas prechilling was done at only different periods. FR-yongjadaemok and FR-kunghap were used as test cultivars and their daily germination rates were measured at treatment levels. The best germination rate of each treatment was shown in a week prechilling at $3^{\circ}C$, a day priming with 100 mM $KNO_3$ and a day treatment with 0.01 mM $GA_3$ although the prechilling had the highest rate among them. The rate of priming treated after the prechilling was continuously decreased with its longer treatment periods and was less than no-priming. In addition, the rate of $GA_3$ treatment after the prechilling was not affected by its concentrations and treatment periods. Priming and $GA_3$ treatments before the prechilling, however, showed similar germiabilities between their treatment levels including no-treatment. The results mean that sequential order of available presowing treatments is important to enhancing the rate.

• Korean Journal of Materials Research
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• v.7 no.8
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• pp.707-713
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• 1997

HVPE(hydride vapor phase epitaxy)법으로 (111)MgAI$_{2}$ $O_{4}$기판위에 GaN 후막을 성장하였다. GaN를 성장하기 전에 기판에 표면을 GaCI로 처리한 수 성장하였을 때 이중 X선 회절 피크의 반치폭이 710 arcsec로서 N $H_{3}$로 처리한 후 성장한 GaN에 비하여 작았으며, 무색 투명의 경면상태가 얻어\ulcorner다. 113$0^{\circ}C$의 온도에서 성장한 GaN 의 광루미네센스(PL)특성과 동일하게 나타났다. 10K의 온도에서 측정된 PL 스펙트럼은 자유여기자와 속박여기자의 재결합천이에 의한 피크들과 Mg과 관련된 도너-억셉터 쌍 사이의 재결합 및 이의 1LO, 2LO, 3LO 및 4 LO 포논복제에 의한 피크들이 나타났다. 성장된 GaN는 n형의 전도성을나타내었으며, 캐리어 이동도와 농도는 각각 21.3$\textrm{cm}^2$/V ㆍsec와 4.2 x $10^{18}$$cm^{-3}$이었다.

• Journal of the Semiconductor & Display Technology
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• v.20 no.4
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• pp.125-129
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• 2021

We investigated the electronic property and atomic structure for chalcopyrite (CH) Al_xGa_1-xAs semiconductor by using first-principles FPLMTO method. The CH-Al_xGa_1-xAs exhibits a p-type semiconductor with a direct band-gap. For low Al concentration unoccupied hole-carriers are induced, but for high Al concentration it is formed a localized bonding or anti-bonding state below Fermi level. The hybridization of Al(3s)-Ga(4s, or 4p) is larger than that of Al(3s)-As(4s, or 4p). And the Al film on As-terminated surface, Al/AsGa(001), is more energetically favorable one than that on Ga-terminated (001) surface. Consequently, the band-gap of CH-Al_xGa_1-xAs system increases exponentially with increasing Al concentration. The change of lattice parameter is shown two different configurations with increasing Al concentration. The calculated lattice parameters for CH-Al_xGa_1-xAs system are compared to the experimental ones of zinc-blend GaAs and AlAs.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.276-276
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• 2011

진공증착법으로 ITO (indium-tin-oxide) 기판 위에 $AgGaSe_2$ 박막을 성장시켜 그 구조와 광학적 특성을 조사하였다. X-선 회절 분석에 의하여 살창상수는 a=5.97 ${\AA}$와 c=10.88 ${\AA}$이고, 황동광(chalcopyrite) 구조를 하고 있었으며, 그 성장 방향은 (112)방향으로 선택 성장됨을 알 수 있었다. 증착된 박막과 200~400$^{\circ}C$로 열처리한 박막의 실온에서 측정한 광학적인 에너지 띠 간격은 2.02 eV에서 2.28 eV까지 변하였다. 또한 열린회로로 구성되어 있는 시료의 표면에 광 펄스를 주입하여 표면에서 형성된 전하들의 거동을 광유기 방전 특성(PIDC) 방법을 이용하여 조사하였다. 초기전위 V0로 형성된 시료의 양단을 주행하는 운반자 농도, 전류밀도 및 전기장 효과를 관찰하여 운반자의 주행시간, 이동도 그리고 전하운반자 농도를 계산한 결과는 각각 42 ${\mu}s$~81 ${\mu}s$, $1.9{\times}10^{-1}\;cm^2/Vs$~$5.7{\times}10^{-2}\;cm^2/Vs$ 그리고 약 $6.0{\times}10^{17}/cm^3$~$2.0{\times}10^{18}/cm^3$이었으며, p-형 전도를 나타내었다. 원자 힘 현미경 실험으로 제곱평균제곱근 거칠기와 입계크기를 조사하였으며, X-선 광전자 분광실험으로 원소들의 결합상태를 관찰하였다.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.313-319
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• 2022

AlGaN/GaN based HfO₂ MOSHEMT (metal oxide semiconductor high electron transistor) with different gate recess depth was simulate to demonstrate a successful normally-off operation of the transistor. Three types of the HEMT structures including a conventional HEMT, a gate-recessed HEMT with 3 nm thick AlGaN layer, and MIS-HEMT without AlGaN layer in the gate region. The conventional HEMT showed a normally-on characteristics with a drain current of 0.35 A at V_G = 0 V and V_DS = 15 V. The recessed HEMT with 3 nm AlGaN layer exhibited a decreased drain current of 0.15 A under the same bias condition due to the decrease of electron concentration in 2DEG (2-dimensional electron gas) channel. For the last HEMT structure, distinctive normally- off behavior of the transistor was observed, and the turn-on voltage was shifted to 0 V.

• Journal of agriculture & life science
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• v.44 no.6
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• pp.1-7
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• 2010

This experiment was conducted to enhance horticultural utilization value of wild graminaceous species on rooftop gardening purpose. Seeds of Pennisetum were harvested 5 times at an interval of 2 weeks from 2 October to 25 November in 2008. Seeds were soaked into solution of $GA_3$ different concentrations and incubated at the condition of $20^{\circ}C$ and $25^{\circ}C$ each for 12 hrs. Germination rate of the after-ripening seeds was above 80% in the 17 and 31 October and 13 November harvest, but germination rate of seeds harvested in the 2 October and 25 November was below 70%. Fresh seed germination and early growth of shoot and root after germination were promoted by $GA_3$ treatment. Effect of $GA_3$ treatments on germinability of fresh seeds was more prominent in the seeds harvested on 2 October and 25 November.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.13-13
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• 2009

본 연구는 MLCC 구성성분의 증발/비등에 의한 저분자물질의 제거가 bar 수축에 미치는 영향도를 평가하기 위해, 압착 bar에서 발생하는 고농도의 out gas를 정량하기 위한 최적 system을 구축하고자 하였다. gas 포집에 범용적으로 사용하는 Purge & Trap sampler 대신 Heating block를 사용하여 gas를 발생시키고 동시에 solvent에 용해시킴으로써 고농도의 시료가 희석될 수 있는 전처리 장치를 디자인하였다. 그 결과 고농도 gas 주입에 의한 장비오염과 peak saturation 문제가 해결되었고, gas phase의 시료를 liquid phase로 상전이 시켜 autosampler를 이용한 정확한 량의 시료 주입이 가능하였다. System의 Gage Linearity와 Bias는 각각 1.7%와 1.3%로 개선이 필요없는 수준의 정확도를 가졌다.