• 제목/요약/키워드: Microwave synthesis

검색결과 235건 처리시간 0.047초

자료동화 토양수분 데이터를 활용한 동아시아지역 수동형 위성 토양수분 데이터 보정: SMOS (MIRAS), GCOM-W1 (AMSR2) 위성 및 GLDAS 데이터 활용 (Revising Passive Satellite-based Soil Moisture Retrievals over East Asia Using SMOS (MIRAS) and GCOM-W1 (AMSR2) Satellite and GLDAS Dataset)

  • 김형록;김성균;정재환;신인철;신진호;최민하
    • 한국습지학회지
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    • 제18권2호
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    • pp.132-147
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    • 2016
  • 동아시아 지역의 위성 토양수분 데이터 활용을 위해 Soil Moisture Ocean Salinity (SMOS) 위성에 탑재된 Microwave Imaging Radiometer using Aperture Synthesis (MIRAS) 센서와 Global Change Observation Mission-Water (GCOM-W1) 위성에 탑재된 Advanced Microwave Scanning Radiometer 2 (AMSR2) 센서 기반 토양수분 데이터를 자료동화 데이터인 Global Land Data Assimilation System (GLDAS)를 기준 값으로 Cumulative Distribution Function (CDF) 기법과 회귀식을 활용하여 보정하는 연구를 수행하였다. 동아시아 지역에서 발생하는 전파간섭의 영향을 고려하여 토양수분 산출에 적합하다고 판단되는 Radio Frequency Interference (RFI), Data Quality indeX (DQX) 한계값과, 합성일수를 제시하였다. 보완된 위성 토양수분 데이터를 지점 토양수분 데이터와 비교한 결과 상관계수가 평균 27%, 11% 증가하였고, Root Mean Square Deviation (RMSD, 평균제곱근 편차)는 평균 61%, 57% 감소하였다. 추가적으로, 보정된 위성데이터를 GLDAS 토양수분 데이터와 비교했을 때, 보정된 MIRAS 및 AMSR2 데이터는 한반도의 80% 및 90%의 지역에서 상관계수가 증가하였으며, 한반도 전역에서 RMSD가 감소하였다. 본 연구를 통해 향후 MIRAS 및 AMSR2 위성 데이터를 융합하여 각 위성의 토양수분 데이터를 보완 할 수 있는 가능성을 제시하였다.

BaO-Pr$_2$O$_3$-TiO$_2$계 및 BaO-(Nd,Pr)$_2$O$_3$-TiO$_2$계 마이크로파 유전체의 합성 및 특성에 관한 연구 (A Study of the Synthesis and the Properties on Microwave Dielectric Material of BaO-Pr$_2$O$_3$-TiO$_2$ and BaO-(Nd,Pr)$_2$O$_3$-TiO$_2$ System)

  • 이용석;이재원;성학제;김준수;이병하
    • 한국세라믹학회지
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    • 제35권8호
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    • pp.775-782
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    • 1998
  • This experiment is third study concerning BaO-{{{{ { { Pr}_{ 2} O}_{3 } }}-{{{{ { TiO}_{2 } }} (Ln=Sm, Nd, Pr, La..) system which is known to show a high dielectric constant and Q value in microwave dielectric materials. The process of cry-stallization and the microwave dielectric properties of the specimens sintered at 1220-140$0^{\circ}C$ for 2 hr was investigated in the BaO-(Na,{{{{ { { Pr})_{2 }O }_{3 } }}-{{{{ { TiO}_{2 } }} as well as BaO-{{{{ { { Pr}_{ 2} O}_{3 } }}-{{{{ { TiO}_{2 } }} system. The single phase BaPr2Ti5O14 and Ba(Nd,{{{{ { { Pr})_{2 }O }_{3 } }}Ti5O14 was finally formed from the Pr2Ti2O7 (Nd, Pr)2Ti2O7 as a secondary phase in the BaO-{{{{ { { Pr}_{ 2} O}_{3 } }}-{{{{ { TiO}_{2 } }} and BaO-(Nd, {{{{ { { Pr})_{2 }O }_{3 } }}-{{{{ { TiO}_{2 } }} system respectively The dielectric constant of the specimens sint-ered at 1280~131$0^{\circ}C$ showed the maximum value as 105(BaO-{{{{ { { Pr}_{ 2} O}_{3 } }}-{{{{ { TiO}_{2 } }} system) and 88 (BaO-(Nd,{{{{ { { Pr})_{2 }O }_{3 } }}-{{{{ { TiO}_{2 } }} system) and the Q values of them showed higher value than 1800 which are due to the maximum den-sity. However the dielectric properties of the specimens sintered at higher temperature than 131$0^{\circ}C$ were reduced due to the increases of pore which were resulted from the sudden grain growth.

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마이크로파 조건에서 여러가지 산화제를 이용한 풀러렌[$C_{60}$의 산화반응 (The Oxidation of Fullerene[$C_{60}$] using Several Oxidants under Microwave Irradiation)

  • 고원배;황성호;안주현
    • Elastomers and Composites
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    • 제40권1호
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    • pp.45-52
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    • 2005
  • 풀러렌[$C_{60}$]은 3-chloroperoxy benzoic acid, benzoyl peroxide, trichloroisocyanuric acid, chromium(VI) oxide 등의 산화제를 사용하여 마이크로파 조건에서 반응시켜 풀러렌 산화물[$C_{60}(O)_n$] ($n=1{\sim}4$ or n=1)을 합성하였다. 동일한 마이크로파 조건에서 여러 가지 산화제와 풀러렌[$C_{60}$]의 고체상태 반응성은 3-chloroperoxy benzoic acid>benzoyl peroxide>trichloroisocyanuric acid$\simeq$chromium(VI) oxide 순으로 증가함을 나타냈다. MALDI-TOF-MS, UV-visible, 그리고 HPLC를 사용하여 분석한 결과 생성된 풀러렌 산화물은[$C_{60}(O)_n$] ($n=1{\sim}4$ or n=1)임을 알 수 있었다.

Doctor blade를 이용한 용액형 CIGS 균일 코팅에 관한 연구 (A Study of CIGS Coated Thin-Film Layer using Doctor Blade Process)

  • 유종수;윤성만;김도진;조정대
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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    • pp.93.2-93.2
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    • 2010
  • Recently, printing and coating technologies application fields have been expanded to the energy field such as solar cell. One of the main reasons, why many researchers have been interested in printing technology as a manufacturing method, is the reduction of manufacturing cost. In this paper, We fabricated CIGS solar cell thin film layer by doctor blade methods using synthesis of CIS precursor nanoparticles ink on molybdenum (Mo) coated soda-lime glass substrate. Synthesis CIS precursor nanoparticles ink fabrication was mixed Cu, In, Se powder and Ethylenediamine, using microwave and centrifuging. Using multi coating process as we could easily fabrication a fine flatness CIS thin-film layer ($0.7{\sim}1.35{\mu}m$), and reduce a manufacture cost and process steps. Also if we use printing and coating method and solution process in each layer of CIGS solar cell (electrode, buffer), it is possible to fabricate all printed thin-film solar cell.

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수산염법에 의한 $Ba_2Ti_9O_{20}$의 합성과 유전특성에 미치는 $ZrO_2$ 첨가의 영향 (Effect of $ZrO_2$ Addition on the Synthesis and Microwave Dielectric Properties of $Ba_2Ti_9O_{20}$ Fabricated by Oxalate method)

  • 박재원;이헌식;이병하
    • 한국세라믹학회지
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    • 제31권8호
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    • pp.835-840
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    • 1994
  • In this study, the synthesis of Ba2Ti9O20 powder having chemically homogeneous and highly pure fine particle size distribution was attempted by the oxalate method. And the effects of ZrO2 addition was investigated. The four compositions (X=0, 0.028, 0.048, 0.068) of Ba2(Ti9-x, Zrx)O20 were prepared by precipitation reaction of BaCl2, TiCl4, and ZrOCl2, with oxalic acid and NH4OH acting as a precipitating agent and a pH regulator respectively, in aqueous solution. In case of 4.8 mol% ZrO2 addition, the single phase Ba2Ti9O20 was obtained at 120$0^{\circ}C$ and its dielectric properties was excellent showing K=40.5, Q=4621 at 5.4 GHz.

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Deuterium-labeling Toward Robust Function of Organic Molecules: Enhanced Photo-stability of Partially Deuterated 1', 3', 3'-Trimethyl-6-nitrospiro[2H-1- benzopyran-2, 2'-indoline]

  • Kawanishi, Yuji;Inoue, Kyoko;Ohta, Shin-Ichi;Miyazawa, Akira
    • Rapid Communication in Photoscience
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    • 제3권4호
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    • pp.64-66
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    • 2014
  • Synthesis of a deuterium-labeled derivative of nitrospirobenzopyran (NSP), one of representative photochromic compounds, has been described. Four deuteriums were successfully introduced on 1-methyl and ${\alpha}$-methyne relative to spiro-carbon in the title compound with more than 95atom%D purity. Main photodegraded products of NSP were two oxindoles in acetonitrile, and additional products were formed in poly(isobutyl-methacrylate) films possibly due to restricted molecular motion in polymer matrix. Quantitative HPLC analysis revealed that partial introduction of deuterium to NSP brought a noticeable isotope effect, recognizable enhancement in photo-resistivity of NSP, i.e.,8.3% in solutions and 29% in polymeric films.