• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.75-76
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• 2018

MiDF, Micro Defect Free concrete, is the concrete made for high strength development by minimizing the defects such as micro pore and ITZ. Since MiDF exhibits strength through hydro-thermal synthesis reaction, it is essential to select the optimum C/S mole ratio. In this study, the basic characteristics of MiDF were evaluated by controlling the C/S mole ratio by SF and QP.

• Current Applied Physics
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• 제18권11호
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• pp.1403-1409
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• 2018

In the present study, the $SrMoO_4:Eu^{3+}$ phosphors has been synthesized through hydro-thermal co-precipitation method, and single factor and orthogonal experiment method was adopted to find optimal synthesis condition. It is interesting to note that hydro-thermal temperature is a prominent effect on the luminescent intensity of $SrMoO_4:Eu^{3+}$ red phosphor, followed by co-precipitation temperature, calcining time, and the doping amount of $Eu^{3+}$. The optimal synthesis conditions were obtained: hydro-thermal temperature is $145^{\circ}C$, co-precipitation temperature is $35^{\circ}C$, the calcining time is 2.5 h, and the doping amount of activator $Eu^{3+}$ is 25%. Subsequently, the crystalline particle size, phase composition and morphology of the synthesized phosphors were evaluated by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The results show that these phosphors possess a scheelite-type tetragonal structure, and the particle size is about $0.2{\mu}m$. Spectroscopic investigations of the synthesized phosphors are carried out with the help of photo-luminescence excitation and emission analysis. The studies reveal that $SrMoO_4:Eu^{3+}$ phosphor efficiently convert radiation of 394 nm-592 and 616 nm for red light, and the luminescence intensity of $SrMoO_4:Eu^{3+}$ phosphors is improved. $SrMoO_4:Eu^{3+}$ phosphors may be a potential application for enhancing the efficiency of white LEDs.

• 콘크리트학회논문집
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• 제20권5호
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• pp.543-548
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• 2008

프리캐스트 제품은 소요의 강도를 단기간에 얻기 위하여 일반적으로 상압 증기양생을 실시하며, 칼슘-실리케이트의 수열합성반응을 이용할 경우 1차 양생 이후에 오토클레이브 양생이라는 2차 양생도 실시하고 있다. 여기에서 제품의 강도발현에 커다란 영향을 미치는 양생 방법의 경우, 2차 양생 방법에 대한 연구는 각종 연구로 부터 수열반응에 적합한 조건이 구명되는 등 많은 연구가 수행되었으나, 1차 양생 방법에 대한 검토는 아직 미비한 실정이며 생산업체별로 양생 방식을 달리하여 제품을 생산하고 있어 제품의 소요강도 획득에 문제점을 가지고 있다. 이에 본 연구에서는 수열합성 경화체에 있어서 보다 높은 강도를 얻기 위한 1차 양생 방법에 대한 자료를 얻고자 실험적 연구를 수행하였다. 즉 수열합성 경화체에 있어서 1차 양생 방법을 건식과 건/습식 그리고 습식으로 실시한 후에 각각의 시험체에 대하여 수화특성을 알아보기 위하여 SEM, XRD, DT-TGA 및 porosimeter 시험을 실시하였으며, 강도 특성을 알아보기 위하여 압축강도 시험을 실시하였다. 측정 결과, 1차, 2차 양생 후 각 양생조건에 따른 시험체의 압축강도는 건/습식 양생조건이 강도발현에 유리한 것으로 나타났으며, 그 차이는 크지 않은 것을 알 수 있었다. 수화도 분석을 위한 SEM, XRD 및 DT-TGA의 측정 결과, 건/습식 양생조건의 경우가 건식과 습식 양생조건에 비해 가장 많이 수화가 진행된 것을 알 수 있었고, porosimeter의 측정 결과에 있어서도 건/습식 양생조건이 강도특성에 유리한 공극특성을 갖는 것으로 나타났다.

• 분석과학
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• 제19권4호
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• pp.309-315
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• 2006

Two piperazine-templated metal sulfate complexes, $(C_4N_2H_{12})[Ni(H_2O)_6](SO_4)_2$, I and ($C_4N_2H_{12}$) $[Co(H_2O)_6](SO_4)_2$, II, have been synthesized by hydro/solvothermal reactions and their crystal structures analyzed by single crystal X-ray diffraction methods. Complex I crystallizes in the monoclinic system, $P2_1/n$ space group, a=12.920(3), b=10.616(2), $c=13.303(2){\AA}$, ${\beta}=114.09(1)^{\circ}$, Z=4, $R_1=0.030$ for 3683 reflections; II: monoclinic $P2_1/n$, a=12.906(3), b=10.711(2), $c=13.303(2){\AA}$, ${\beta}=114.10(2)^{\circ}$, Z=4, $R_1=0.032$ for 4010 reflections. The crystal structures of the piperazine-templated metal(II) sulfates demonstrate zero-dimensional compound constituted by diprotonated piperazine cations, metal(II) cations and sulfate anions. The structures of complex I and II are substantially isostructural to that of the previously reported our piperazine-templated copper(II) sulfate complex $(C_4N_2H_{12})[Cu(H_2O)_6](SO_4)_2$. The central metal(II) atoms are coordinated by six water molecules in the octahedral geometry. The crystal structures are stabilized by three-dimensional networks of the $O_{water}-H{\cdots}O_{sulfate}$ and $N_{pip}-H{\cdots}O_{sulfate}$ hydrogen bonds between the water molecules and sulfate anions and protonated piperazine cations. Based on the results of thermal analysis, the thermal decomposition reactions of the complex I was analyzed to have three distinctive stages whereas the complex II proceed through several stages.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.603-603
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• 2013

3D 배열구조의 Vertical nanowire Integrated Nanogenerator (VING)은 낮은 출력, 유연 기판 상에 부적합, 나노선의 부서지기 쉬움, 장기 안정성, 균일한 나노선의 성장을 필요로 하는 문제점을 가지고 있다. 본 연구에서는 이러한 VING방식의 단점을 보완하여 2D 배열 구조의 Lateral nanowire Integrated Nanogenerator (LING)로 고출력 전압, 유연기판의 상에 적합 등을 개선하는 방향으로 연구를 하였다. 본 연구의 실험 방법으로는 RF magnetron sputter를 이용하여 AZO Seedlayer를 제작하였으며 제작된 AZO Seedlayer를 photolithography 공정으로 제작하였다. 패터닝된 샘플을 Hydro thermal synthesis method로 성장시켰다. 구조적 분석으로는 XRD, FE-SEM 등을 이용하여 측정하였다.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2008년도 Asian Magnetics Conference
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• pp.48.1-48.1
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• 2008

• 대한화학회지
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• 제60권5호
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• pp.321-326
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• 2016

Two new polymeric complexes, [Zn(dpa)(pyz)_0.5]_n (1; dpa = diphenate and pyz = pyrazine) and [Mn₃(bpdc)₃(py)₄]_n (2; bpdc = biphenyl-4,4'-dicarboxylate and py = pyridine) were successfully isolated by the hydro- and solvo-thermal technique, respectively. The complexes were characterized by elemental and thermal analysis, vibrational IR spectroscopy, and by single crystal x-ray structure determination. For 2, magnetic property was also investigated. Complex 1 is a two-dimensional layer structure consisting of a paddle-wheel building unit of Zn-dpa chains bridged by pyrazine. While, complex 2 consists of linear trimeric Mn3 cluster as building unit to form 3D network. In the complexes, dpa²⁻ (1) and bpdc²⁻(2) ligands show a typical bis-monodendate bridging and two kinds of bridging modes; a typical bridging and chelating/bridging mode, respectively.

• 한국세라믹학회지
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• 제23권3호
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• pp.15-20
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• 1986

Formation of powders and electromechanical coupling factor of $Pb(Mn_{1/3} Sb_{2/3})_{0.08} Ti_{0.495}Zr_{0.425}O_3$ by hydro-thermal synthesis are described. The hydrothermal reactions each were accomplished at 12$0^{\circ}C$~25$0^{\circ}C$ for 5hours and sintering was accomplished at 1, .20$0^{\circ}C$ for 1hours. The PZT powders by hydrothermal synthesis were formed above 16$0^{\circ}C$ and the forms were cubic types. The ratio of grain size of sintered sample to powder was slowly decreased with the rising of hydrothermal reactino temperature but decreased rapidly above 22$0^{\circ}C$ Sintering density was decreased with the rising of hydrothermal reaction temperature above 16$0^{\circ}C$ but dielectric constant was increased. Electromechanical coupling factor $K_P$ was almost constant at 16$0^{\circ}C$~24$0^{\circ}C$ range and the value of $K_P$ was about 0.43-0.45.

• 융합정보논문지
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• 제11권12호
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• pp.30-38
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• 2021

본 논문에서는 열화상 이미지에서의 열 데이터 추출 및 해당 데이터를 사용한 발열 설비 탐지 향상 기법을 제안한다. 주요 목표는 열화상 이미지에서 바이트 단위로 데이터를 해석하여 열 데이터와 실화상 이미지를 추출하고 해당 이미지와 데이터를 합성한 합성 이미지를 딥러닝 모델에 적용하여 발열 설비의 탐지 정확도를 향상 시키는 것이다. 데이터는 한국수력원자력발전소 설비 데이터를 사용하였으며, 학습 모델로는 Faster-RCNN을 사용하여 각 데이터 그룹에 따른 딥러닝 탐지 성능을 비교 평가한다. 제안한 방식은 Average Precision 평가에서 기존 방식에 비해 평균 0.17 향상 되었다.본 연구는 이로서 국가 데이터 기반 열화상 데이터와 딥러닝 탐지의 접목을 시도하여 유효한 데이터 활용도 향상을 이루었다.

• 상하수도학회지
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• 제19권4호
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• pp.455-461
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• 2005

This study was designed to investigate the fundamental aspects of a possible recovery of phosphorus strategy from wastewater by using the zirconium mesoporous structured materials as a new type of ion exchangers. Zirconium mesoporous structure material was synthesized by hydro-thermal synthesis. The synthesized zirconium mesoporous structure was examined by X-ray diffraction (XRD) and Transmission electron micrograph (TEM). From the results of XRD and TEM, it was found out that hexagonal mesoporous structure, pore size was about $47{\AA}$, was synthesized. Experimental results showed that the complex of zirconium sulfate tetrahydrate and surfactant micelles had very high ability for capture of phosphorus. The amount of phosphate ions exchanged into the solid was as great as 3.4mmol/g-ZS. And the ion exchange reaction was occurred between $PO_4{^{3-}}$ and $SO_4{^{2-}}$ and also between $PO_4{^{3-}}$ and $OH^-$. Therefore, it is possible to get the higher removal efficiency than other ion exchange media and adsorbent.