Na₂S 하부층을 이용한 Cu(In,Ga)Se₂ 광흡수층의 저온증착 및 Cu(In,Ga)Se₂ 박막태양전지에의 응용

신해나라,신영민,김지혜,윤재호,박병국,안병태,Shin, Hae Na Ra,Shin, Young Min,Kim, Ji Hye,Yun, Jae Ho,Park, Byung Kook,Ahn, Byung Tae 한국태양광발전학회 2014 Current Photovoltaic Research Vol.2 No.1

High-efficiency in $Cu(In,Ga)Se_2$ (CIGS) solar cells were usually achieved on soda-lime glass substrates due to Na incorporation that reduces deep-level defects. However, this supply of sodium from sodalime glass to CIGS through Mo back electrode could be limited at low deposition temperature. Na content could be more precisely controlled by supplying Na from known amount of an outside source. For the purpose, an $Na_2S$ layer was deposited on Mo electrode prior to CIGS film deposition and supplied to CIGS during CIGS film. With the $Na_2S$ underlayer a more uniform component distribution was possible at $350^{\circ}C$ and efficiency was improved compared to the cell without $Na_2S$ layer. With more precise control of bulk and surface component profile, CIGS film can be deposited at low temperature and could be useful for flexible CIGS solar cells.

Na₂S 하부층을 이용한 Cu(In,Ga)Se₂ 광흡수층의 저온증착 및 Cu(In,Ga)Se₂ 박막태양전지에의 응용

신해나라(Hae Na Ra Shin),신영민(Young Min Shin),김지혜(Ji Hye Kim),윤재호(Jae Ho Yun),박병국(Byung Kook Park),안병태(Byung Tae Ahn) 한국태양광발전학회 2014 Current Photovoltaic Research Vol.2 No.1

High-efficiency in Cu(In,Ga)Se₂ (CIGS) solar cells were usually achieved on soda-lime glass substrates due to Na incorporation that reduces deep-level defects. However, this supply of sodium from sodalime glass to CIGS through Mo back electrode could be limited at low deposition temperature. Na content could be more precisely controlled by supplying Na from known amount of an outside source. For the purpose, an Na₂S layer was deposited on Mo electrode prior to CIGS film deposition and supplied to CIGS during CIGS film. With the Na₂S underlayer a more uniform component distribution was possible at 350°C and efficiency was improved compared to the cell without Na₂S layer. With more precise control of bulk and surface component profile, CIGS film can be deposited at low temperature and could be useful for flexible CIGS solar cells.

Energy storage capabilities of nitrogen-enriched pyropolymer nanoparticles fabricated through rapid pyrolysis

Yun, Young Soo,Kim, Yu Hyun,Song, Min Yeong,Kim, Na Rae,Ku, Kyojin,An, Ji Su,Kang, Kisuk,Choi, Hyoung Jin,Jin, Hyoung-Joon Elsevier 2016 Journal of Power Sources Vol.331 No.-

<P><B>Abstract</B></P> <P>Nanostructured pyropolymers contain significant amounts of redox-active heteroatoms, have high specific surface areas, and a defective carbon microstructure, indicating good potential for pseudocapacitive charge storage. In this study, nitrogen-enriched pyropolymer nanoparticles (N-PNs-50) are fabricated from polyaniline nanotubes through rapid pyrolysis at 50 °C min<SUP>−1</SUP>. N-PNs-50 exhibit a nitrogen content of 9.8 wt%, a high specific surface area of 875.8 m<SUP>2</SUP> g<SUP>−1</SUP>, and an amorphous carbon structure with an I<SUB> <I>D</I> </SUB>/I<SUB> <I>G</I> </SUB> intensity ratio of 0.95. These unique characteristics lead to good electrochemical performances, in which reversible capacities of 660 and 255 mAh g<SUP>−1</SUP> are achieved for Li-ion and Na-ion storage, respectively, with favorable voltage characteristics (<1.5 V for Li-ions and <1.2 V for Na-ions). This study provides a more feasible production method for nitrogen-doped pyropolymers and their practicable electrochemical performances for use as an anode in energy storage devices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nanostructured pyropolymers (N-PNs-50) were fabricated by rapid pyrolysis. </LI> <LI> N-PNs-50 exhibited a nitrogen content of 9.8 wt% and amorphous carbon structure. </LI> <LI> N-PNs-50 exhibited a high specific surface area of 875.8 m<SUP>2</SUP> g<SUP>−1</SUP>. </LI> <LI> 660 and 255 mAh g<SUP>−1</SUP> were achieved for Li-ion and Na-ion storage, respectively. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Nitrogen-enriched pyropolymer nanoparticles (N-PNs-50) were fabricated from polyaniline nanotubes through rapid pyrolysis at 50 °C min<SUP>−1</SUP>, showing superior electrochemical performances.</P> <P>[DISPLAY OMISSION]</P>

유아의 성개념 형성에 관한 연구

김나림,김지영 한국영유아보육학회 2003 한국영유아보육학 Vol.0 No.34

This study is investigated to the young children's concept formation about sex. Research questions were as follows; 1) Is there any difference about concept of sex according to young children's age and sex? 2) Is there any difference about concept of difference on the sex according to young children's age and sex? Subjects of this study were 158 children of 4 and 5 years of age from D and S Children's House in J city. The researchers interviewed the subjects by using a specially designed interview format. Responses of children were classified in accordance with criteria developed by researchers on the basis of the researcher's previous studies, the study of Jeong(1991), Jeong(1996) and that of Park(2001). The data was analyzed by M, SD, two independent t-tests and frequencies, percentages with spss/pc program. The study results found that 1) gender identity and gender stability of 4 years old and 5-year-old children were developed almost mostly, and Young girls were expose that develop little more. 2) The 4 years old and 5-year-old children were recognizing about biologic difference of man and woman regardless of age and that girls were recognizing little more high. Children who respond that biologic special quality is same responded that appearance and psychological special quality are equal. And that consecrated vessel is identical, ratio that recognize is low. If examine infants who respond that there is biologic difference, was recognizing that dress and sexual gland are different mainly. But, that body part is different when painted, ratio that express is high.

Hierarchically nanoporous pyropolymer nanofibers for surface-induced sodium-ion storage

Yoon, Hyeon Ji,Lee, Min Eui,Kim, Na Rae,Yang, Seung Jae,Jin, Hyoung-Joon,Yun, Young Soo Pergamon Press 2017 Electrochimica Acta Vol. No.

<P><B>Abstract</B></P> <P>Surface-driven charge storage materials based on both electrochemical double layer (EDL) formation and pseudocapacitive behavior can deliver high energy and power capabilities with long-lasting cycling performance. On the other hand, the electrochemical performance is strongly dependent on the material properties, requiring sophisticated electrode design with a high active surface area and a large number of redox-active sites. In this study, hierarchically nanoporous pyropolymer nanofibers (HN-PNFs) were fabricated from electrospun polyacrylonitrile nanofibers by simple heating with KOH. The HN-PNFs have a hierarchically nanoporous structure and an exceptionally high specific surface area of 3,950.7m<SUP>2</SUP> g<SUP>−1</SUP> as well as numerous redox-active heteroatoms (C/O and C/N ratio of 10.6 and 16.8, respectively). These unique material properties of HN-PNFs resulted in high reversible Na-ion capacity of ∼292mAhg<SUP>−1</SUP> as well as rapid kinetics and stable cycling performance in the cathodic potential range (1-4.5V vs. Na<SUP>+</SUP>/Na). Furthermore, energy storage devices based on HN-PNFs showed a remarkably high specific energy of ∼258 Wh kg<SUP>−1</SUP> at ∼245Wkg<SUP>−1</SUP> as well as a high specific power of ∼21,500Wkg<SUP>−1</SUP> at ∼78 Wh kg<SUP>−1</SUP>, with long and stable cycling behaviors over 2,000 cycles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Hierarchically nanoporous pyropolymer nanofibers (HN-PNFs) were fabricated. </LI> <LI> HN-PNFs have a high specific surface area of ∼3,950m<SUP>2</SUP> g<SUP>−1</SUP> and numerous heteroatoms. </LI> <LI> HN-PNFs exhibit high capacities of ∼292mAhg<SUP>−1</SUP> and great rate/cycling performances. </LI> <LI> High energy (258Whkg<SUP>−1</SUP>) and high power (21,500Wkg<SUP>−1</SUP>) are achieved. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Hierarchically nanoporous pyropolymer nanofibers (HN-PNFs) fabricated from electrospun polyacrylonitrile nanofibers by simple heating with KOH exhibited high electrochemical performance for Na-ion storage.</P> <P>[DISPLAY OMISSION]</P>

품종별 무화과의 영양성분 비교

나환식 ( Hwan Sik Na ),김진영 ( Jin Young Kim ),박학재 ( Hak Jae Park ),최경철 ( Gyeong Cheol Choi ),양수인 ( Soo In Yang ),이지헌 ( Ji Heon Lee ) 한국식품저장유통학회(구 한국농산물저장유통학회) 2013 한국식품저장유통학회지 Vol.20 No.3

국내에서 주로 재배되는 무화과 품종인 도후인(Dauphine)2종, 봉래시(Horaish)2종, 바나네(Banane) 1종을 대상으로 이화학적 특성을 분석한 결과, 무화과의 수분은 85.37~87.28%, 회분 0.38~0.43%, 조지방 0.20~0.26%, 조단백질 0.39~0.81%로 품종별 차이는 보이지 않았으며 조섬유는 바나네가 7.55±0.13%로 다른 품종 5.12~7.60%에 비해 다소 높은 결과를 보였다. 무기성분 함량은 모든 품종에서 K>Ca>Mg>Na순으로 나타났으며 전체 함량의 경우 도후인 품종이 타 품종에 비해 조금 높은 결과를 보였다. 바나네 품종과 봉래시 품종의 총 유리아미노산 조성은 glutamic acid>proline>aspartic acid 순으로 높은 분포를 보였으며, 전체 함량의 51.68~58.71%를 차지하고 있으며, 도후인 품종의 경우 glutamic acid>aspartic acid>alanine이 전체의 약 50%를 차지하고 있었다. 또한 기억력 감퇴 예방 등 학습 능력에 도움을 주는 기능성 물질인 γ-aminobutyric acid(GABA) 함량은 바나네에서 26.69mg/100g으로 상당히 높은 함량을 보였다. 총 폴리페놀 함량은 도후인이 198.91~261.64mg/kg, 봉래시 품종이 169.90~174.33mg/kg, 바나네 품종이 211.07mg/kg으로 나타났으며 총 플라보노이드 함량은 바나네(84.95mg/kg), 도후인(60.47~68.71mg/kg), 봉래시(44.12~44.60mg/kg)순으로 바나네가 가장 높았으며 품종간의 차이를 보였따. 플라보노이드성분 중 quercetin과 kaempferol은 각각 2.40~3.54mg/kg, 1.09~1.16mg/kg으로 분석되었다. In this study, the proximate compositions, minerals, free amino acids, total polyphenol and flavonoids of figs were analyzed according to their cultivars. The proximate compositions showed moisture at 85.37~87.28%, crude ash at 0.38~0.43%, crude lipid at 0.20~0.26%, crude protein at 0.39~0.81%, carbohydrate at 11.23~13.66% and crude fiber at 5.12~7.55% (dry base). The amounts of the following minerals in the figs were highest, in this order: K > Ca > Mg > Na. The total polyphenol contents were highest in this order: Dauphine (198.91~261.64mg/kg), Banane (211.07 mg/kg) and Horaish (169.90~174.33 mg/kg). The total flavonoid contents were highest in this order. Banane (84.52 mg/kg) > Dauphine (60.47~68.71 mg/kg) > Horaish (44.12~44.60mg/kg). The quercetin contents were highest in this order. Dauphine, 2.40~3.54 mg/kg; Banane, 3.54 mg/kg; and Horaish, 2.40~2.75 mg/kg; but the flavonoid contents were lowest in this order. Dauphine, 1.11~1.16 mg/kg; Banane, 1.14 mg/kg; and Horaish, 1.09~1.11 mg/kg. The free amino acid content of the figs was 199.70~328.77 mg/100g; their essential free amino acid contents, 46.45~67.46 mg/100 g; and their GABA (γ-aminobutyric acid) contents, 13.57~26.69 mg/100 g.

경계조건변화에 따른 동력전달관로의 동특성

나기대,유영태,김지환 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.6

Design for a quiet operation of fluid power system requires the understanding of noise and vibration characteristics of the system. It's not easy to analyze noise problem in hydraulic cylinder used in typical actuator Because they've got complex fluid dynamics. One of the fundamental problems associated with the hydraulic system is the pulsating flow in pipe lines, which can e tackled by the analysis under simplifying assumptions. The present study focuses on theoretic analysis and experimental study on the dynamics of laminar pulsating flow in a circular pipe. We analyze the propagation characteristics of the pressure pulse within a hydraulic pipe line taking into account the pulsating flow frequency variation. We also measure instantaneous pressure pulses within pipe line to identify the transfer functions. We conduct series of experiments to investigate the propagation characteristics of pressure pulse for various pressure of pulsating flow. The working fluid of the present study is ISO VG46 and the temperature ranges from 20 to 60℃ with normal pressure at 4000kPa. The flow rate is measured by using an ultrasonic flow meter. Pressures at fixed upstream and downstream positions are measured concurrently. The electric signals of the pressure sensor are stored and analyzed using a system analyzer(PKE 983 series). The frequency is varied in the range of 10~500Hz. The Reynolds number is kept below 2,000. In the present study, boundary condition was varied by installing a surge tank and an orifice at the end of pipe. Experimental and theoretical results were compared each other under various boundary conditions.

수에 대한 유아의 인식 : 문식성 연구 비교를 중심으로 Compared with Literacy Study

김지영,김나림 한국영유아보육학회 2003 한국영유아보육학 Vol.0 No.32

This study is compared a previous study about children's perception of letters to children's perception of numbers through formal and informal mathematics education, and investigates recognition of degree of difficulty and reasons for learning letters and numbers through educational activity. The researchers interviewed 140 children, 70 aged 4 and 70 aged 5 and the children's responses were classified according to criteria previously developed by Weiss & Hagen(1988) and Wing(1989). The major findings were ; (1) Most of the children learned the formal knowledge of numbers from their parents. The older the children the more positively they perceived their capacity for writing and reading numbers and understood it for routine by practical means, (2) Most of the children recognized that learning about numbers is easier than learning to print.

색상 측정 기기를 이용한 복합레진 적층 수복과 단일 수복의 색상 비교 분석

송영상,김자현,이빈나,장지현,장훈상,황윤찬,오원만,황인남 大韓齒科保存學會 2012 Restorative Dentistry & Endodontics Vol.37 No.2

Objectives: This study analyzed the difference in color caused by different thickness in enamel layer of composite resins when applied with single and layering placement technique, and evaluated if the results agreed with the shade guide from the manufacturers to verify reliability of the color matching process of the manufacturers. Materials and Methods: For single composite resin samples, 6 mm diameter and 4 mm thickness cylindrical samples were fabricated using Ceram-X mono (DENTSPLY DeTrey) and CIE L*a*b* values were measured with spectrophotometer. Same process was done for layering compositie resin samples, making 3 dentinal shade samples, 4 mm thickness, for each shade using Ceram-X duo (DENTSPLY DeTrey) and enamel shade resins were layered in 2 mm thickness and CIE L*a*b* values were measured. These samples were ground to 0.2 mm thickness each time, and CIE L*a*b* values were measured to 1 mm thickness of enamel shade resin. Results: Color difference (△E*) between single and layering composite resin was 1.37 minimum and 10.53 maximum when layering thicknesses were between 1 mm and 2 mm and 6 out of 10 same shade groups suggested by manufacturer showed remarkable color difference at anythickness (△E* > 3.3). Conclusion: When using Ceram-X mono and duo for composite resin restoration, following the manufacturer's instructions for chossing the shade is not appropriate, and more accurate information for Ceram-X duo is needed on the variation and expression of the shades depending on the thickness of the enamel. (Restor Dent Endod 2012;37(2):84-89)

보리순의 영양성분 조성

서혜지,최용민,김상천,이준수,이기택,정명근,천지연,황진봉,남진식,서우덕,황영,김행란,김세나 忠北大學校 農業科學硏究所 2015 農業科學硏究 Vol.31 No.2