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.

Cloning, Purification, and Characterization of a New DNA Polymerase from a Hyperthermophilic Archaeon, Thermococcus sp. NA1

( Yun Jae Kim ),( Hyun Sook Lee ),( Seung Seob Bae ),( Jeong Ho Jeon ),( Jae Kyu Lim ),( Yo Na Cho ),( Ki Hoon Nam ),( Sung Gyun Kang ),( Sang Jin Kim ),( Suk Take Kwon ),( Jung Hyun Lee ) 한국미생물생명공학회 2007 Journal of microbiology and biotechnology Vol.17 No.7

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>

A Na⁺-coupled C₄-dicarboxylate transporter (Asuc_0304) and aerobic growth of <i>Actinobacillus succinogenes</i> on C₄-dicarboxylates

Rhie, Mi Na,Yoon, Hyo Eun,Oh, Hye Yun,Zedler, Sandra,Unden, Gottfried,Kim, Ok Bin Society for General Microbiology 2014 Microbiology Vol.160 No.7

<P><I>Actinobacillus succinogenes</I>, which is known to produce large amounts of succinate during fermentation of hexoses, was able to grow on C<SUB>4</SUB>-dicarboxylates such as fumarate under aerobic and anaerobic conditions. Anaerobic growth on fumarate was stimulated by glycerol and the major product was succinate, indicating the involvement of fumarate respiration similar to succinate production from glucose. The aerobic growth on C<SUB>4</SUB>-dicarboxylates and the transport proteins involved were studied. Fumarate was oxidized to acetate. The genome of <I>A. succinogenes</I> encodes six proteins with similarity to secondary C<SUB>4</SUB>-dicarboxylate transporters, including transporters of the Dcu (C<SUB>4</SUB>-dicarboxylate uptake), DcuC (C<SUB>4</SUB>-dicarboxylate uptake C), DASS (divalent anion : sodium symporter) and TDT (tellurite resistance dicarboxylate transporter) family. From the cloned genes, Asuc_0304 of the DASS family protein was able to restore aerobic growth on C<SUB>4</SUB>-dicarboxylates in a C<SUB>4</SUB>-dicarboxylate-transport-negative <I>Escherichia coli</I> strain. The strain regained succinate or fumarate uptake, which was dependent on the electrochemical proton potential and the presence of Na<SUP>+</SUP>. The transport had an optimum pH ~7, indicating transport of the dianionic C<SUB>4</SUB>-dicarboxylates. Transport competition experiments suggested substrate specificity for fumarate and succinate. The transport characteristics for C<SUB>4</SUB>-dicarboxylate uptake by cells of aerobically grown <I>A. succinogenes</I> were similar to those of Asuc_0304 expressed in <I>E. coli</I>, suggesting that Asuc_0304 has an important role in aerobic fumarate uptake in <I>A. succinogenes</I>. Asuc_0304 has sequence similarity to bacterial Na<SUP>+</SUP>-dicarboxylate cotransporters and contains the carboxylate-binding signature. Asuc_0304 was named SdcA (<U>s</U>odium-coupled C<SUB>4</SUB>-<U>d</U>i<U>c</U>arboxylate transporter from <I><U>A</U></I>. <I>succinogenes</I>).</P>

Hollow Cobalt Selenide Microspheres: Synthesis and Application as Anode Materials for Na-Ion Batteries

Ko, You Na,Choi, Seung Ho,Kang, Yun Chan American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.10

<P>The electrochemical properties of hollow cobalt oxide and cobalt selenide microspheres are studied for the first time as anode materials for Na-ion batteries. Hollow cobalt oxide microspheres prepared by one-pot spray pyrolysis are transformed into hollow cobalt selenide microspheres by a simple selenization process using hydrogen selenide gas. Ultrafine nanocrystals of Co3O4 microspheres are preserved in the cobalt selenide microspheres selenized at 300 degrees C. The initial discharge capacities for the Co3O4 and Cobalt selenide microspheres selenized at 300 and 400 degrees C are 727, 595, and 586 mA h g(-1), respectively, at a current density of 500 mA g(-1). The discharge capacities after 40 cycles for the same samples are 348, 467, and 251 mA h g(-1), respectively, and their capacity retentions measured from the second cycle onward are 66, 91, and 50%; respectively. The hollow cobalt selenide microspheres have better rate performances than the hollow cobalt oxide microspheres.</P>

Electrochemical properties of ultrafine Sb nanocrystals embedded in carbon microspheres for use as Na-ion battery anode materials

Ko, You Na,Kang, Yun Chan The Royal Society of Chemistry 2014 Chemical communications Vol.50 No.82

<P>Ultrafine Sb nanocrystals, uniformly distributed in a carbon matrix with a microspherical morphology, were synthesized by one-pot spray pyrolysis. The Sb–carbon composite microspheres exhibited good Na-storage properties with stable cyclability, a capacity retention of 90% over 100 cycles, and good rate performance.</P> <P>Graphic Abstract</P><P>The preparation of Sb–carbon composite microspheres and their electrochemical performance are investigated. Sb nanocrystals embedded in a microspherical carbon matrix exhibited superior Na-storage performances. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c4cc05275g'> </P>

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>

중합광원과 레진 색상이 복합레진의 중합깊이에 미치는 영향

나준석,정선와,황윤찬,김선호,윤창,오원만,황인남 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.6

Purpose of this research is estimating polymerization depth of different source of light. XL 3000 for halogen light, Apollo 95E for plasma arc light and Easy cure for LED light source were used in this study. Different shade (B1 & A3) resin composites (Esthet-X, Dentsply, U.S.A.) were used to measure depth of cure. 1, 2, and 3 mm thick samples were light cured for three seconds, six seconds or 10 seconds with Apollo 95E and they were light cured with XL-3000 and Easy cure for 10 seconds, 20 seconds, or 40 seconds. Vicker's hardness test carried out after store samples for 24 hours in distilled water. Results were as following. 1. Curing time increases from all source of lights. curing depth increased(p<0.05). 2. Depth (that except 1mm group and 2mm group which lighten to halogen source of light) deepens in all groups, Vicker's hardness decreased(p<0.05). 3. Vicker's hardness of A3 shade composite was lower in all depths more than B1 shade composites in group that do polymerization for 10 seconds and 20 seconds using halogen source of light(p<0.05), but group that do polymerization for 40 seconds did not show difference(p>0.05). 4. Groups that do polymerization using Plasma arc and LED source of light did not show Vicker's hardness difference according to color at surface and 1mm depth(p>0.05), but showed difference according to color at 2mm and 3mm depth(p<0.05). The results showed that Apollo 95E need more polymerization times than manufacturer's recommendation (3 seconds), and Easy cure need polymerization time of XL-3000 at least.

중년기 여성의 상체부 특성

나미향 권윤희 청주대학교 학술연구소 2009 淸大學術論集 Vol.14 No.-

The purpose of study is research on breast shape and suitable bressiere for middle aged women. For this purpose, numerous antropometric measurements and other related data 200 subjects were analyzed by various statistical methods. Changes in the somatotype of the upper body were studied according to age group through classifying middle aged women into three age categories of Aged 35 to 44, Aged 45 to 54, Aged 55 to 64 and the measured anthropometry. It appears that the physical stance of the aging female becomes more bent and their body structures become smaller due to the bending and stretching of upper body during the process of ageing of each somatotype. The results of the comparative analysis of anthropolatric data from three groups(Groups Ⅰ: Aged 35 to 44, Group Ⅱ: Aged 45 to 54, Group Ⅲ: Aged 55 to 64)show that getting older, breast heights are decreased significantly and widths, depths and bust girths are increased. Various length measurements related to the drooping degree of breast are increased.