Ether-free polymeric anion exchange materials with extremely low vanadium ion permeability and outstanding cell performance for vanadium redox flow battery (VRFB) application

Cha, Min Suc,Jo, Sang Woo,Han, Seung Hui,Hong, Soo Hyun,So, Soonyong,Kim, Tae-Ho,Oh, Seong-Geun,Hong, Young Taik,Lee, Jang Yong Elsevier 2019 Journal of Power Sources Vol.413 No.-

<P><B>Abstract</B></P> <P>Ether-free poly(<I>p</I>-phenylene)-based anion exchange membrane materials with outstanding vanadium ion blocking properties are reported. The synthesized ionomers with a rigid backbone structure show small dimensional variations despite the high ion exchange capacities. Among the synthesized membranes, the QPPP-2 membrane with ion exchange capacity of 2.1 meq·g<SUP>−1</SUP> exhibits high anion (OH<SUP>−</SUP>, SO<SUB>4</SUB> <SUP>2−</SUP>, and Cl<SUP>−</SUP>) conductivity. The QPPP-2 membrane shows an extremely low diffusion coefficient (2.12 × 10<SUP>−9</SUP> cm<SUP>2</SUP> min<SUP>−1</SUP>) for VO<SUP>2+</SUP>, which is much lower than that of Nafion 115 (2.88 × 10<SUP>−6</SUP> cm<SUP>2</SUP> min<SUP>−1</SUP>), indicating the vanadium ion blocking property of QPPP-2. Moreover, the chemical and operational stabilities of the membranes are investigated <I>via</I> ex situ soaking tests in 0.1 M VO<SUB>2</SUB> <SUP>+</SUP> solution and in situ operation tests for 100 cycles, respectively. The vanadium redox flow battery single cell assembled with the QPPP-2 membrane exhibits a coulombic efficiency of 99%, voltage efficiency of 87%, and energy efficiency of 86% during 100 cycles at 80 mA cm<SUP>−2</SUP>. The excellent chemical, morphological, and electrochemical properties of the QPPP-2 membrane make it suitable for use in vanadium redox flow battery.</P> <P><B>Highlights</B></P> <P> <UL> <LI> AEMs are fabricated by a Ni(0)-catalyzed cross-coupling reaction. </LI> <LI> The synthesized ionomers indicated excellent dimensional and chemical stability. </LI> <LI> Ether-free polymeric AEMs showed extremely low vanadium ion cross over. </LI> <LI> The performance of developed AEM showed high EE (87%) with high capacity retention. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Crosslinked anion exchange membranes with primary diamine-based crosslinkers for vanadium redox flow battery application

Cha, Min Suc,Jeong, Hwan Yeop,Shin, Hee Young,Hong, Soo Hyun,Kim, Tae-Ho,Oh, Seong-Geun,Lee, Jang Yong,Hong, Young Taik Elsevier 2017 Journal of Power Sources Vol.363 No.-

<P><B>Abstract</B></P> <P>A series of polysulfone-based crosslinked anion exchange membranes (AEMs) with primary diamine-based crosslinkers has been prepared via simple a crosslinking process as low-cost and durable membranes for vanadium redox flow batteries (VRFBs). Chloromethylated polysulfone is used as a precursor polymer for crosslinked AEMs (CAPSU-x) with different degrees of crosslinking. Among the developed AEMs, CAPSU-2.5 shows outstanding dimensional stability and anion (Cl<SUP>−</SUP>, SO<SUB>4</SUB> <SUP>2−</SUP>, and OH<SUP>−</SUP>) conductivity. Moreover, CAPSU-2.5 exhibits much lower vanadium ion permeability (2.72 × 10<SUP>−8</SUP> cm<SUP>2</SUP> min<SUP>−1</SUP>) than Nafion 115 (2.88 × 10<SUP>−6</SUP> cm<SUP>2</SUP> min<SUP>−1</SUP>), which results in an excellent coulombic efficiency of 100%. The chemical and operational stabilities of the membranes have been investigated via ex situ soaking tests in 0.1 M VO<SUB>2</SUB> <SUP>+</SUP> solution and in situ operation tests for 100 cycles, respectively. The excellent chemical, physical, and electrochemical properties of the CAPSU-2.5 membrane make it suitable for use in VRFBs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The crosslinking between polymer chains are constructed by 4,4′-diaminobenzophenone. </LI> <LI> The crosslinked AEMs were fabricated by commercial polysulfone (PSU; Udel<SUP>®</SUP> P-3500). </LI> <LI> The crosslinked AEM based on PSU indicated good chemical and dimensional stability. </LI> <LI> The performance of crosslinked AEM showed high EE (86%) with high capacity retention. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

상악 구개측 중앙부에 매복된 과잉치

민성진,최형준,,김성오,이제호,곽지윤,최병재 大韓小兒齒科學會 2005 大韓小兒齒科學會誌 Vol.32 No.4

과잉치는 치배 형성기에 정상 치판의 과도한 증식의 결과로 발생하며 산발적일 수도 있고 유전적일 수도 있다. 발생 빈도는 1~3%이며,2:1의 비율로 남아에게 호발한다. 주로 상악 전방부에서 많이 발견되며, 매복, 영구치의 위치 이상, 정중부 이개, 낭종, 비강으로의 맹출 등과 같은 다양한 합병증을 나타낼 수도 있다. 상악 전방부에서 발견되어지는 과잉치는 치축방향에 따라 위치가 결정되며 상악 전방부 과잉치의 1/3 정도는 역위 매복되어 맹출의 가능성이 없지만, 치낭의 치관 부위가 정상적인 관계로 존재하는 한 과잉치의 이동이 일어날 수 있다. 치아의 이동은 경구개, 소구치 부위, 비강까지도 일어날 수 있다. 또한 전상악 수직고경의 성장으로 시간이 지남에 라 외과적 접근이 어려워질 수 있다. 이에 본 두 증례에서는 역위 매복된 상악 전방부의 과잉치가 구개 측 중앙부까지 이동된 것을 발견하여 외과적으로 제거하였다. Supernumerary tooth develops as a result of abnormal proliferation of the dental lamina during the initiation stage of dental development. It could be a sporadic occurrence or a hereditary transmission. Supernumerary tooth occurs with a frequency of 1 to 3%, Generally, there is a 2:1 preference for boys. It is usually found in the anterior portion of the maxilla and may be associated with complications such as impaction, malposition of permanent teeth, formation of diastema, cysts and eruption into nasal cavity. The position of supernumerary tooth found in the anterior portion of the maxilla is determined by the axis of the tooth. One third of supernumerary tooth in the anterior portion of the maxilla has no possibility of eruption due to its invertedly impacted position. However, as long as the coronal part of the follicle remain intact, migration of supernumerary tooth is possible. The migration may occur into the palate, the premolar region, the sinus or the nasal cavity. Also, growth of vertical dimension of maxilla could make surgical approach difficult as time goes by. For this reason, we have found invertedly impacted mesiodens moved to the vault of the palate in the two cases, and extracted supernumerary tooth surgically.

보호계전기 정정을 위한 Open Interface 개념의 사용자 환경 설계

吳成民,崔勉松,李承宰 明知大學校 産業技術硏究所 2004 産業技術硏究所論文集 Vol.23 No.-

KEPCO is using power system protection business developing PROSET2000 to computerize synthesis. This system is database and synthesis computing program that have correction automation program etc., for protective relaying business. PROSET2000's Human Machine Interface(HMT) that is designed by GOMS could not reflect justly user's requirement. Studied new design method of HMI for fast penumbra of user's requirement. Apply and designs Open Interface technique in view of software methodology to solve problem of performance of existent PROSET2000 system. System developer can receive optimum service by offering interface(Meta Interface) that user can exhibit on outside, and change achievement strategy etc., that must select according to circumstance among embodiment contents in case apply Open Interface technique. Could reflect requirement of PROSET2000 development time shortening and user fast by developing HMI to Open Interface concept. Can improve PROSET2000 performance by selecting Open Interface concept.

함입된 상악 중절치의 외과적 재위치 후 예후

민성진,최형준,류정아,김성오,이제호,최병재,손흥규 대한소아치과학회 2006 大韓小兒齒科學會誌 Vol.33 No.3

폴리아닐린을 이용한 전기변색소자의 제작 및 특성

오응주,이경민,민혜경,노성변,서정선 명지대학교 자연과학연구소 1995 자연과학논문집 Vol.12 No.-

ITO/폴리아닐린/고분자고체전해질/ITO구조의 전기변색소자가 제작되었다.IM p-toluenesulfonic acid 용액내에서 0.7V의 전압하에 potentiostaic method로 아닐린을 전기화학적으로 중합하여 salt form의 폴리아닐린을 ITO glass 위에 deposite시켰다.또한 화학적으로 합성한 base form의 폴리아닐린을 10? torr의 압력하에 진공승화법에 의해 ITO glass 위에 증착시켰다. PEI(polyethyleneimine)과 2-acrylamido-2-methyl-propanesulfonic acid 를 이용하여 고분자 고체전해질을 제조하였다. 제작된 ITO/polyaniline salt/고분자고체전해질/ITO 구조의 전기변색소자는 인가전압 -2.0V~+2.OV의 영역에서 무색에서 푸른색을 나타내었다.Potential pulse를 통하여 측정된 이들 변색소자의 cyvlic number 는 10? 이상으로 나타났고, 응답시간은 50ms로 생기는 전자전이를 통하여 색의 변화를 알 수 있었다. 또한 각각 변색물질로 폴리아닐린 salt 와 base를 사용하여 제작된 변색소자의 경우 I-V곡선은 counter 이온인 SO?-의 발생확률에 따라 다른 곡선을 나타내었다. Electrochromic devices(ECD) with ITO/polyaniline/polymer solid electrolyte /ITO structure were fabricated . In these devices both of poyaniline salt and base forms were deposited onto ITO conducting glass substrate by electrochemical and vacuum sublimation method, respectively, Polymer solid electrolye were prepared by the reaction of polyethyleneimine with 2-acrylamido-2-methyl-propanesulfonic acid . ECDs based on polyaniline salt showed color change from colirless to blue in the range of applied voltage of -2.OV ~+2.0V.Cyclic number and response time of these devices appear to be 10? and 50ms respectively. The color change which is relatd to teh electronic transition by the variation of electron density was observed from the UV/Vis. spectra measurement. I-V curves for ECDs based on polyaniline salt and base repectively shoe different behaviors due to the different degree of contribution of SO?- ion as a counterion for each case.

심부 매복 정중 과잉치 수술 시 마취방법 선택

민수영,송제선,이제호,최형준,손흥규,김성오 大韓小兒齒科學會 2012 大韓小兒齒科學會誌 Vol.39 No.1

Supernumerary tooth occurs most frequently at premaxilla area. Followed by mandibular premolar area, mandibular fourth molar area, maxillary paramolar area. Mesiodens are mainly impacted in the palatal area and surgical approach is made at palatal side. The time of surgery remains controversial. In case of inverted or horizontal impacted supernumerary tooth, intraosseous tooth movement and vertical growth of premaxilla makes surgical extraction more difficult. And also the more quantity of removed bone is, the higher degree of difficulty is. Inverted mesiodens of these cases were impacted superior to apex level of adjacent permanent incisor. Although CT examination revealed exact location of impacted tooth, surgical procedure including ostectomy may take a long time more than expected. So, before surgical extraction, it’s need to be considered several factors such as necessity of CT taking, degree of difficulty, direction of surgical approach, necessity of general anesthesia etc. 정중 과잉치(mesiodens)는 대개 상악 절치부에서 발견되며, 주로 구개측에 위치하는 경향이 있다. 정중 과잉치의 자연맹 출 가능성이 관찰되면, 주기적으로 검사하여 구강내로 충분히 맹출한 후에 단순발치를 시행한다. 주기적 검사에서 자연맹출 소견이 보이지 않거나, 형태이상 혹은 맹출방향의 이상으로 구강 내로 자연맹출 할 가능성이 없으면, 수술적 제거방법을 고려 해야 할 것이다. 특히, 인접한 중절치나 측절치의 맹출을 방해하고 있는 상황이 관찰된다면, 빠른 시일 내에 과잉치 제거를 위 한 수술적 방법을 시도하는 것이 타당하다. 한편, 외과적 수술의 시기를 늦추는 것을 고려해야 하는 경우도 있다. 정중과잉치가 인접하여 발육중인 정상 치아의 맹출을 방해하지 않는 경우이다. 이때, 삼차원 CT사진을 촬영하여보면, 과잉치 주변으로 영구절치의 치배가 근접하여 성곽처럼 둘러 싸고 있는 것을 볼 수 있다. 미성숙한 치배가 둘러 싸고 있는 상황에서, 무리하게 과잉치를 제거하려고 시도할 경우 인접 치배 를 손상시킬 가능성을 배제하기 어렵다. 이 점을 고려 한다면, 가급적 인접한 치아의 치근이 보다 발육한 후에 수술을 시도하 는 것이 바람직할 것이다. 초등학교 2학년 이상의 어린이들은 외래에서 국소마취하 제거하는 수술방법에 대개 잘 적응하며 고학년이 될수록 보다 수월해진다. 수술시기를 너무 늦추거나, 과잉치가 너무 늦게 발견된 경우 구개측 심부로 깊이 이동한 것을 볼 수 있다. 때로는 과잉치의 위치가 처음부터 심부에 매복되어 있을 수 있다. 이와 같은 경우, 전신마취방법을 생각해 볼 수 있을 것이다. 본 증례는 상악 정중부의 깊은 부위에 역위 매복된 과잉치를 외래에서 국소마취하에 치료를 시도할 때 관찰되는 문제점을 고찰하였고, 전신마취방법을 결정하기 위한 기준을 제시하였다. 심부 매복된 치아의 외과적 발거시 어린이의 행동조절이 가장 큰 문제였으며, 방사선 소견상 과잉치 치관의 위치가 절치의 치근단보다 상방에 위치할 경우 전신마취로 전환 하는 것이 바람직 할 것으로 사료된다.

이개 재건술 후 늑연골 공여부의 분석

백승준,임재호,백룡민,오갑성,백세민 大韓成形外科學會 1997 Archives of Plastic Surgery Vol.24 No.5

The harvesting of costal cartilage for the total ear reconstruction elicits various functional and aesthetic problems such as pneumothorax, atelectasis, pain, scar and chest contour deformities. Although the costal cartilage has been the most popular autogenous tissue for the total ear reconstruction, the studies about problems of donor site after harvesting the costal cartilage were relatively rare. From March 1989 to October 1996, 153 cases of total ear reconstruction by the costal cartilage framework insertion were done in our hospital and 61 cases whose follow up were done over 6 months were analysed for donor site scar, contour deformity and rate of satisfaction. The optimal age of microtia reconstruction was considered as over the age of 8, because of the growth of the ear and the volume of costal cartilage. Through a small incision, 3 ~ 4 cm, on the contralateral chest, the 6th, 7th and 8th costal cartilage were harvested with the outer layer of perichondrium for survival of the costal cartilage framework, the inner layer of perichondrium was remained for the growth of costal cartilage. There were 4 cases of uneventful pleural perforation, and remained no problems on the patients. The state of chest donor site were analyzed on 61 patients by use of medical records, medical photos and interview with the patients. Mean length and width of chest scar were 5.2 cm and 2.3 mm 79% of patients classified as excellent or acceptable. Chest contour deformity was observed on 39% and 85% of patients were satisfied with the result of donor site.

Ring-on-ring 강도시험법을 이용한 200mm 반도체 실리콘 웨이퍼의 파괴강도 분석

정성민,박성은,오한석,이홍림 연세대학교 산업기술연구소 2000 논문집 Vol.32 No.2

Biaxial fracture strength of the commercial 200mm Czochralski single crystal silicon wafer was measured by the ring-on-ring technique and was compared with theoretical strength of Si single crystal. The ring-on-ring apparatus was newly designed and manufactured after analyzing stress distribution in ring-on-ring test with FEM(Finite Element Method) computerized simulation. Weibull modulus of the silicon wafer was also calculated from the measured fracture strength.

반안면 왜소증의 수술적 교정: 5년간 65례의 고찰

백승준,김진오,백롱민,오갑성,백세민 大韓成形外科學會 1997 Archives of Plastic Surgery Vol.24 No.5

Hemifacial microsomia is a descriptive term for the developmental anomaly affecting the tissues derived from 1st and 2nd branchial arches, expressed as asymmetric underdevelopement in facial bony skeleton. Conventional strategy of surgical correction for hemifacial microsornia consists of leveling though maxillary LeFort osteotomy and rotation, advancement and recession through bilateral sagittal split us osteotomy, which was reinforced by ancillary procedures such as mandibular augmentation with onlay bone graft, mandibular angle ostectomy, temporomandibular dibular joint (TMJ) reconstruction and malar reconstruction. But these like conventional methods for correction of hemifacial microsomia were emphasized on the correction of vertical asymmetry primarily, overlooked the asymmetry of horizontal plane, namely hypoplastic malar deformity. In general, correction of malar hypoplasia was achieved by rib or calvarial bone graft. These methods remain donor site deformity and the result can not be precisely predicted due to progressive resorption of bone. Moreover, the natural appearance of zygomatic complex could not be established by bone graft. Malar expansion by zygomatic osteotomy and spread-out technique was applied on correction for 34 case in total 65 cases of hemifacial microsomia from March 1991 to February 1996. We could get more natural appearance of malar complex and facial symmetry in the correction of hemifacial microsomia at one stage operation than conventional malar reconstruction methods.