Compatibility of lithium salts with solvent of the non-aqueous electrolyte in Li–O₂ batteries

Du, Peng,Lu, Jun,Lau, Kah Chun,Luo, Xiangyi,Bareñ,o, Javier,Zhang, Xiaoyi,Ren, Yang,Zhang, Zhengcheng,Curtiss, Larry A.,Sun, Yang-Kook,Amine, Khalil The Royal Society of Chemistry 2013 Physical chemistry chemical physics Vol.15 No.15

<P>The stability of lithium salts, especially in the presence of reduced oxygen species, O<SUB>2</SUB> and H<SUB>2</SUB>O (even in a small amount), plays an important role in the cyclability and capacity of Li–O<SUB>2</SUB> cells. This combined experimental and computational study provides evidence that the stability of the electrolyte used in Li–O<SUB>2</SUB> cells strongly depends on the compatibility of lithium salts with solvent. In the case of the LiPF<SUB>6</SUB>–1NM3 electrolyte, the decomposition of LiPF<SUB>6</SUB> occurs in the cell as evidenced by <I>in situ</I> XRD, FT-IR and XPS analysis, which triggers the decomposition of 1NM3 solvent due to formation of HF from the decomposition of LiPF<SUB>6</SUB>. These reactions lead to degradation of the electrolyte and cause poor cyclability of the cell. The same reactions are not observed when LiTFSI and LiCF<SUB>3</SUB>SO<SUB>3</SUB> are used as the lithium salts in 1NM3 solvent, or LiPF<SUB>6</SUB> is used in TEGDME solvent.</P> <P>Graphic Abstract</P><P>We provided evidence that the stability of the electrolyte used in Li–O<SUB>2</SUB> cells strongly depends on the compatibility of lithium salts with solvent. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3cp50500f'> </P>

TiO2 광촉매를 이용한 수용액 내의 벤즈알데히드의 광분해반응

최경희 ( Choe Gyeong Hui ),안병준 ( An Byeong Jun ),장원길 ( Jang Won Gil ),신형식 ( Sin Hyeong Sig ),양오봉 ( Yang O Bong ) 한국공업화학회 2003 공업화학 Vol.14 No.7

자외선 조사하에서 TiO₂를 촉매로 하여 벤즈알데히드의 광촉매 분해반응을 행하였다. 침전법에 의하여 제조된 여러 가지 TiO₂촉매의 활성을 비교하였고 반응조건에 따른 광분해 활성을 조사하였다. 벤즈알데히드의 초기농도가 6 ppm일때 P25촉매가 가장 우수하였으며, 광촉매량을 1~10 g/L로 변화시킨 결과 5 g/L에서 6 h 후에 96%의 제거율로 최대를 나타냈다. 100%의 아나타제로된 P101과 P102 촉매는 P25보다 비표면적이 4배 이상이었으나 벤즈알데히드의 분해 활성은 P25 보다 낮았다. 벤즈알데히드의 분해 메카니즘을 규명하기 위한 in-냐셔 FT-IR 특성 분석 결과 TiO₂ 표면에 가스 상 O₂로부터 반응종인 O^(-)(ads)과 OH radical이 형성되고, TiO₂에 흡착된 벤즈알데히드가 O^(-)(ads)의 공격을 받아 벤젠고리가 끊어져 알코올이 형성되며, 알데히드 → 카르복시산 → nCO₂ + nH₂O으로 완전 산화되는 광산화 반응 mechanism을 제안할 수 있었다. Photocatalytic degradation of benzaldehyde in aqueous phase has been investigated with various TiO2 catalysts under UV irradiation. Photocatalytic activities of p25(Degussa) and TiO₂ (P101 and P102) prepared by a precipitation method were studied as a function of reaction condition. The maximum degradation rate, 96% of benzaldehyde (initial concentration 6 ppm) was achieved with 5g/L of P25 in the range of 1-10g/L photocatalyst. P101 and P102 TiO₂ exhibit lower activity than P25 even though these have 100% anatase phase and about 4 times higher specific surface area than P25. By in-situ FT-IR study, we could propose the photo-degradation mechanism of benzaldehyde as following sequence : at first, O^(-)(ads) and OH radical were formed from oxygen gas on TiO₂; alcohol was formed due to the cession of aromatic ring which was attacked by O^(-)(ads); again oxidized to aldehyde, carboxylic acid and finally to carbon dioxide and water.

Dimethyl Phthalate의 오존산화 반응에 관한 연구

이철규(Cheal Gyu Lee),송준오(Jun O Song) 大韓環境工學會 2013 대한환경공학회지 Vol.35 No.10

실험실적 규모의 순환형 회분식 반응기에서 Dimethyl phthalate (DMP)성분을 효율적으로 제거하기 위하여 Al₂O₃촉매의 주입 그리고 반응온도의 조건을 달리하여 오존산화 반응을 수행하였다. 산화 반응에서 오존의 유량은 1.0 L min-1, 오존 농도를 300 ± 10 mg L-1로 일정하게 유지 하였으며, 산화 반응이 진행되는 60분 동안 10분 간격으로 pH, CODCr와 TOC를 측정하여 이를 비교 분석하였다. O₃/Al₂O₃에서는 O₃ 단독 공정에 비해 CODCr 및 TOC 측정값에 기초한 제거효율은 증가하였으며, 20℃에서 CODCr 및 TOC의 반응속도상수는 3.65 × 10-4 sec-1, 2.52 × 10-4 sec-1, 활성화 에너지는 0.75 kcal·mol-1, 0.70 kcal·mol-1로 각각 나타났다. Ozonation was performed under various experimental conditions that Al₂O₃ catalysts dosage and temperature for removal of DMP in laboratory scale batch reactor. Flow rate of ozone 1.0 L min-1 and ozone concentration of 300 ± 10 mg L-1 were maintained constantly, and the pH, CODCr and TOC was measured in 10 min intervals during the 60 min at oxidation processes. As a result, the presence of the Al₂O₃ than only ozonation increased the removal efficiency of both CODCr and TOC in solution. The pseudo first-order rate constants for the elimination of CODCr and TOC were 3.65 × 10-4 sec-1, 2.52 × 10-4 sec-1, and activation energy was 0.75 kcal·mol-1 and 0.70 kcal·mol-1 at 20℃, respectively.

족관절 골절의 임상적 고찰

김기용,윤준오,이수호,신헌규 울산대학교 의과대학 1992 울산의대학술지 Vol.1 No.1

The ankle joint is a modified complex hinge joint which plays an important role in weight bearing, walking and standing. So, the goals of treatment of ankle fracture are anatomical positioning of the talus in the mortise and regaining a smooth articular surface. The Lauge-Hansen classification of ankle fracture is useful because it characterized the mechanism and sequence of injury and in particular, emphasizes the associated ligamentous injuries. But, it is more complex and all fractures do not conform exactly to one of the described pattern. The Danis-Weber classification of ankle fracture is simpler, emphasized the importance of the lateral side of the ankle, and is usuful in planning surgical treatment. Initially this system did not distinguish the extent of involvement and was too inclusive. The problem has been addressed in the AO classification. The system proposed by Tile is easy to remember and emphasized the importance of assessing and relating stability to the structures that are injured. We analyzed 124 cases of ankle fracture, most of which were treated surgically by AO methods, in the Orthopedic Department, University of Ulsan Medical College, Asan Medical Center from July 1989 to March 1992. The results obtained from this study were as follows : 1. The most common victim was 3rd-5th decade's man. 2. The most common type of Danis-Weber classification was type C(36.3%) and most common type of AO classification was type C1(15.3%), C2(15.3%). According to the classification of Lauge-Hansen, the most common type was pronation-external rotation (42.7%). 3. In Danis-Weber type B and C, satisfactory results were obtained by operative treatment. 4. Danis-Weber's classification and A-O classification were very practical criteria for treatment of the ankle fracture.

새로운 퀴놀론계 항균제 DWQ-013의 항균작용

유영효(Young Hyo Yu),박남준(Nam Jun Park),김병오(Byung O Kim),최문정(Moon Jung Choi),심점순(Jeom Soon Shim),강태충(Tae Chung Kang),이재욱(Jae Wook Lee),김대영(Dae Young Kim) 대한약학회 1994 약학회지 Vol.38 No.3

In vitro and in vivo antibacterial activities of DWQ-013(1-cyclopropyl-6,8-difluoro-7-(3-methylthiomethylpyrrolidinyl)-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid), a new fluoroquinolone antibacterial agent, were compared with those of ciprofloxacin, sparfloxacin and ofloxacin against aerobic and anaerobic standard strains and clinical isolates. DWQ-013 had a broad spectrum and potent antibacterial activity against Gram-positive and Gram-negative bacteria. The antibacterial activity of DWQ-013 against Staphylococcus aureus was equal to that of sparfloxacin(SPFX) and superior to those of ciprofloxacin(CPFX). The antibacterial activity against Gram-negative bacteria was slightly lower than those of ciprofloxacin and sparfloxacin. MIC of DWQ-013 against Pseudomonas aeruginosa(0.781- 1.563mcg/ml) was usually equal to that of sparfloxacin(O.781mcg/ml) and was inferior to that of ciprofloxacin(O.098mcg/ml). The number of viable cells was decreased rapidly after addition of DWQ-013 at concentration of 1-2 folds of MIC.

고온가스정제공정의 후류 연료가스를 이용한 SO₂의 직접환원에 관한 연구

박노국,김봉석,이종대,전진혁,류시옥,이태진 한국공업화학회 2003 응용화학 Vol.7 No.2

The catalytic reactivity for the direct sulfur recovery from the produced SO₂in the regeneration process to element sulfur with the slip-stream fuel gas of hot gas desulfurization process as reductant was studied. The the catalyst for directly sulfur recovery process was used Ce_(0.8)Zr_(0.2)O₂, and the SO₂conversion and the element sulfur yield were investigated with the change of a reaction conditions, such as the amount of H₂O(2-10vol%), the reaction temperatures(400-600℃) and the mole ratio of reactants([reductant]/[SO₂]〓 1.0-3.0). The SO₂conversion and the element sulfur yield decreased by increasing the amount of H₂O in the slip-stream fuel gas using as reductant and increased by increasing the reaction temperature and the mole ratio of reactants. From TPR experiment result, reason that the SO₂conversion and the element sulfur yield becomes low by H₂O was confirmed because that the water-gas shift reaction(CO + H₂O → CO₂+ H₂). Specially, the element sulfur yield was fallen due to that created hydrogen to the water-gas shift reaction is converted to H₂S reacting with element sulfur.

$CHF_3/C_2F_6$ 반응성이온 건식식각에 의한 실리콘 표면의 변형에 관한 연구

박형호,권광호,곽병화,이수민,권오준,김보우,성영권,Park, Hyeong-Ho,Gwon, Gwang-Ho,Gwak, Byeong-Hwa,Lee, Su-Min,Gwon, O-Jun,Kim, Bo-U,Seong, Yeong-Gwon 한국재료학회 1991 한국재료학회지 Vol.1 No.4

실리콘 산화막을 $CHF_{3/}C_2F_6$ 혼합가스를 사용하여 반응성이온 건식식각을 행할 때 실리콘 표면에 형성되는 잔류막과 손상층을 X-선 광전자 분광기(XPS)와 이차이온 질량 분석기(SIMS)를 사용, 연구하였다. 실리콘, 탄소, 산소 및 불소의 angle-resolved XPS분석기술을 이용한 비파괴적 화학결합상태의 깊이분포 분석을 통하여 잔류막의 표면부에 O-F 결합이 존재하며 잔류막은 주로 탄소와 불소의 결합체인 C-F 플리머로 구성되어져 있고 Si-O, Si-C 및 Si-F 결합 등이 존재함을 알았다. 손상층은 실리콘 표면에서 약 60nm 깊이까지 탄소와 불소의 침투에 의해 형성되어져 있음을 알았다. The effects of $SiO_2$ reactive ion etching (RIE) in $CHF_{3/}C_2F_6$ on the surface properties of the underlying Si substrate were studied by X-ray photoelectron spectroscopy(XPS) and secondary ion mass spectrometry(SIMS) techniques. Angle-resolved XPS analysis was carried out as non-destructive depth profile one for investigating the chemical bonding states of silicion, carbon, oxygen and fluorine. The residue layer consists of C-F polymer. O-F bond was found on the top of the polymer layer and Si-O, Si-C and Si-F bonds were detected between Si substrate and polymer film. A 60nm thick damaged layer of silicon surface mainly contains carbon and fluorine.

이중 증기 통로를 가진 히트파이프의 작동유체 평가

전철호,장영석,김오근,노인창 동아대학교 생산기술연구소 2000 生産技術硏究所硏究論文集 Vol.5 No.1

The evaluation of heat transport within a heat pipe with double vapor path and working fluid of different kinds were experimental investigated. Experiments carried out with acetone/ethanol, ethanol/ethanol, etc heat pipe of various with aluminium container of two way vapor path. Performance measurements can be operated at high levels , over 27000 w/㎡ heat flux at 100mm long evaporator. The constitute of 2 way vapor heat pipe was enough to apply the vast range working. In this study, reliable basic data obtained by testes in the 2 way vapor path heat pipe can be used for thermal design, manufacture, production etc.

동(銅)히트파이프를 가진 회전축의 전열특성에 관한 연구

전철호,장영석,김오근 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.-

The purpose of this research is to study the heat transfer characteristics of rotating shaft using copper heat pipe by experiment. An experimental investigation has been carried out on the whole heat transfer rate of shaft with various binding materials as silicone and copper, lead ets. In case of type #2 using lead material, the heat transport characteristics is the most superior of all. The thermal performance of the heat output be showed effect of improvement 12% more than #1 only steel material. As the revolution per minute inceases, the thermal resistance between vapor and outside wall of the condenser can be increased.

일부 농촌 지역 주부의 가족 계획에 관한 조사 : 경기도 양주군 미금면 중심으로 MI-Geum Myun, Yang-Ju Gun, Kyung-Gi Do

전혜정,이미애,문옥련 이화여자대학교 의과대학 1980 梨花醫學誌 Vol.- No.12

A study was carried out, in order to know the status of family planning practice of rural community housewives, in Mi-Geum Myun, Yang-Ju Gun, Kyung-Gi Do. For the study, out of 1,167 households, 380 housewives were sampled as study group who are married and aged under 45years. For the data collection, home visiting survey was done from August 9 to 16, 1979 during the summer vacation and the collected data was analized from December 24, 1979 to January 15, 1980 during winter vacation. And following results were obtained. 1) Of the 380 housewives studied, the fecund woman was 358(94.1%) in total and the highest rate of fecund woman was 100.0% in the age group under 25 and the lowest was 81.3% in the age group of 40-44. 2) Out of 358 fecund woman, present user of contraception was 41.6%(149) in total and the highest rate of present user was 60.9% in the age group of 35-39 and the lowest was 14.6% in the age group under 25. 3) The rate of present user according to the education level of housewives was 36.7% in the group of less than primary school, 42.4% in middle and high school, and 50.0% in college. 4) Among 149 woman of contraception methods user, 52.6% of them was selected temporary contraception methods. The rate of temporary method was higher in the age group of 29(70.0%) than other groups of age (52.2-53.2%). 5) Main source of information on contraception method fro housewives was health workers of health subcenter (50.0%), neighbor housewives (26.5%), her husband (6.3%), community mothers club (4.7%) and others (12.5%).