3D flexible Si based-composite (Si@Si₃N₄)/CNF electrode with enhanced cyclability and high rate capability for lithium-ion batteries

Kim, Si-Jin,Kim, Min-Cheol,Han, Sang-Beom,Lee, Gyu-Ho,Choe, Hui-Seon,Kwak, Da-Hee,Choi, Sun-Yong,Son, Byung-Goo,Shin, Myoung-Sun,Park, Kyung-Won Elsevier 2016 Nano energy Vol.27 No.-

<P><B>Abstract</B></P> <P>Despite extremely high capacity of Si-based anodes in lithium-ion batteries (LIB), Si-based materials have shown a structural collapse caused by a volumetric expansion/contraction during the cycling process. The conventional electrode structure, which consists of active materials, a current collector, a conducting agent, and a binder, actually showed a low loading of active material due to the other heavy components. In this study, we prepared a 3D flexible Si-composite electrode consisting of core (Si)-shell (Si<SUB>3</SUB>N<SUB>4</SUB>) NPs (Si@Si<SUB>3</SUB>N<SUB>4</SUB>) and carbon nanofibers (denoted as Si-composite/CNF). The Si-composite/CNF was directly utilized as an anode in the absence of the other components was electrochemically evaluated using a coin-type cell. The Si-composite/CNF showed a high capacity of 665mAhg<SUP>−1</SUP> at a fairly high current density of 10Ag<SUP>−1</SUP> and an extremely low capacity loss for 2000 cycles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We prepared Si-composite/CNF exhibits a 3D flexible Si-composite electrode. </LI> <LI> The electrode consists of core (Si)-shell (Si<SUB>3</SUB>N<SUB>4</SUB>) NPs (Si@Si<SUB>3</SUB>N<SUB>4</SUB>) and carbon nanofibers. </LI> <LI> The Si-composite/CNF was directly utilized as an anode. </LI> <LI> Si-composite /CNF exhibited high specific capacity and improved high rate cycling performance. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Association Among Self-Injury, Suicidal Tendency, and Personality and Psychological Characteristics in Korean Adolescents

Kyojin Yang,Si Young Kim,Hyejin Kim,Jun-Won Hwang 대한신경정신의학회 2022 PSYCHIATRY INVESTIGATION Vol.19 No.1

Objective To compare mental health problems and personality characteristics between adolescents with self-injury (SI) and suicidal tendency (ST), including suicidal ideation and suicide planning. Methods The participants completed the Adolescent Personality and Mental Health Problems Screening Questionnaire, Third version (AMPQ-III), and Korean version of the Strengths and Difficulties Questionnaire (SDQ-Kr), and gave their demographic information. Based on the answered SI and ST items in AMPQ-III, the participants were divided into groups: without SI and ST, with SI and without ST, without SI and with ST, and with SI and ST. Analysis of variance (ANOVA) and post-hoc Scheffe test were used to determine group differences, stepwise multiple linear regression, and factors associated with SI and ST. Results ANOVA yielded results for all categories of mental health problems. Significant differences were observed between the four groups. Conversely, for personality characteristics, only the sense of community item between the group without SI and with ST and the group without SI and ST were significantly different; sense of community was associated with ST (β=-0.054, p=0.005). Among the mental health subscales, SI was significantly associated with conduct problems (β=0.211, p<0.001), emotional problems (β=0.173, p<0.001), peer problems (β=0.085, p<0.001), and prosocial behavior (β=0.073, p<0.001). ST was significantly associated with emotional symptoms (β=0.317, p<0.001), peer problems (β=0.130, p<0.001), conduct problems (β=0.106, p<0.001), hyperactivity (β=0.050, p=0.010), and prosocial behavior (β=0.062, p<0.001). Conclusion The findings highlight the necessity of assessing psychological strength, difficulties, and personality characteristics for the prevention and early intervention of adolescent SI.

급성신부전을 동반한 알콜성 횡문근융해증 2례

김영민,오동렬,이원재,김형국,황두영,이환,최경호,정시경,김세경,김영옥 大韓應急醫學會 1998 대한응급의학회지 Vol.9 No.4

Rhabdomyolysis is a biochemical and clinical syndrome caused by lysis of skeletal muscle cell and release of muscle cell contents into the circulation. In addition to traumatic cause, various nontraumatic causes have been reported. Rhabdomyolysis has frequently been associated with seamy aspects of life and society: alcoholic abuse, drug addiction, sadistic drill exercise, war events and attempted suicide. The abuse of alcohol causes many hazards in many organs. One of these is acute alcoholic myopathy that may present as a fulminent syndrome of muscle pain and tenderness associated with rhabdomyolysis and acute renal failure. Because the prognosis of adequately treated rhabdomyolysis is excellent, early recognition and prompt management are essential in emergency situation. We experienced two typical cases of alcohol-induced rhabdomyolysis with acute renal failure and report these cases with literature review.

1T DRAM with Raised SiGe Quantum Well for Sensing Margin Improvement

Si-Won Lee,Seongjae Cho,Il Hwan Cho,Garam Kim 대한전자공학회 2023 Journal of semiconductor technology and science Vol.23 No.1

In this paper, a novel one-transistor dynamic random-access memory (1T DRAM) with a raised SiGe quantum well (QW) under one gate in the double-gate (DG) structure is proposed. The proposed structure can improve the poor performance of the retention time and sensing margin which is the problem of the conventional 1T DRAM. In write operation, the performance is improved through the band to band tunneling (BTBT) between body and drain and through valence band offset between SiGe and Si. Also by utilizing the physical barrier of oxide, read “1” retention time can be increased. The fabrication process is also proposed.

백서 척수후근절로부터 슈반세포의 효과적인 체외 배양법

김성민,이종호,김남열,안강민,최원재,최시호,차미주,이주영,황순정,장정원,명훈,최진영,서병무,정필훈,김명진 大韓顎顔面成形再建外科學會 2003 Maxillofacial Plastic Reconstructive Surgery Vol.25 No.4

Schwann cells(SCs), an important component of the peripheral nervous system, intract with nerous to mutually support growth and replication for the peripheral nerve regentation. Recently, ading SCs to the lumen of guidance channel is widely tried to improve regeneration or to make regeneration possible over otherwise irreparable gaps. however, it is not easy to isolate and multiplicate SCs as much as enough to help the axonal regeneration. For the allogeneic SCs source for tubular nerve guidance, we developed a little bit improved technique of harvesting and multiplicating SCs. by culturing dispersed dorsal root ganglia in specially designed medium with growth factors and serial processing, we repeatedlly generate relatively homogenous SC cultures. Our technique was compared with other methods of literature using immunostaining methods such as GFAP, S100, BDNF and the total SC count assessment at different time interval after primary culture.

조혈모세포이식 환자에서 침습성 진균 감염에 대한 Micafungin의 예방 효과 및 안전성

김시현,이동건,최수미,권재철,박선희,최정현,유진홍,이성은,조병식,김유진,이석,김희제,민창기,조석구,김동욱,이종욱,민우성,박종원 대한감염학회 2010 감염과 화학요법 Vol.42 No.3

Background: Micafungin, a potent inhibitor of 1,3-β-D-glucan synthase, is a novel antifungal agent of the echinocandin class. In vitro study showed that micafungin was effective against Aspergillus species as well as Candida species, but clinical data on the prophylactic efficacy against invasive fungal infections (IFIs) other than candidiasis are still lacking. Materials and Methods: We identified 60 consecutive adult hematopoietic stem cell transplantation (HSCT) recipients who received at least 3 doses of micafungin during neutropenic period. Micafungin was started as an alternative in patients who were intolerant or had adverse events (AEs) to primary prophylactic antifungal agents. We retrospectively reviewed the medical records and analyzed the efficacy and safety of micafungin for prophylaxis against IFIs. Results: The patients either had autologous (n=9) or allogeneic (n=51: 1 syngeneic, 24 sibling, 26 unrelated donor) HSCT. Itraconazole oral solution (n=58) was the most frequently used first line antifungal agent for prophylaxis and was administered for median 11 days. The most frequent cause of switch to micafungin was vomiting (n=42). The duration of neutropenia and micafungin administration was median 13 and 12 days, respectively. A successful outcome was achieved in 45 (75%) patients. Empirical antifungal therapy was initiated in 13 (22%) patients. There were 2 cases (3.3%) of breakthrough fungal infections which comprised a probable invasive pulmonary aspergillosis and a possible invasive fungal sinusitis. There was no case of invasive candidiasis. A total of 53 (88%) patients experienced at least one AE regardless of causality during micafungin administration. The most frequent AEs were hypokalemia, vomiting, diarrhea, and elevated serum aspartate aminotransferase or alanine aminotransferase. Among the aforementioned AEs, only 1 case of diarrhea could be classified as a probable relation with micafungin when causality was assessed. There was no AEs that caused discontinuation of micafungin. Conclusions: Micafungin seems to be a safe and effective agent for prophylaxis of IFIs including aspergillosis as well as candidiasis in HSCT recipients. However, further large, prospective, and randomized comparative studies are warranted for aspergillosis.

생존 페르스와 19세기 말의 앤틸리스 제도: 「찬사」의 공간에 대한 문화지리학적 연구

김시원(KIM, Si-Won) 프랑스학회 2015 프랑스학연구 Vol.71 No.-

Éloges est une œuvre au tobiographique de Saint-John Perse. Il est né en 1887 aux Anti lles et i l y a grandi avant son départ pour la France. M algré l'ambiguïté intentionnelle, le poète nous pr ésente à travers le paysage une géographie des Anti lles. Il décrit un paysa ge qui rappelle les Antille s et nous constato ns dans É loges l'environnem ent tropique, climat, topogra phie, végétation, mais au ssi des paysages des pet ites villes modernisées, p ort, route, école , Hal le, etc. Nous tentons d'aborder l'espace d'Éloge s, au regard de la "géographi e de vérité", rapporté e à l'exp loration critique de la société et de la cultu re, au-delàde la "géographi e objective". N otr e lecture de cet espace poétique est associée donc à une moralité. Quo i que soit l'intention du p oète lui-même, il est inévitabl e, pour le lecte ur d'Éloges, qu'il y tro uve des sujets critique s, import ants pour la géo graphie culturelle contemporaine. Nous constat ons, dan s "Pour fêter un e enfance", "Eloges", quel ques élémentssugg éra nt la hiér archisation social e, économique, ainsi que raciale, celle-ci est raccrochée au pouvoir qui domine dans les îles, es pace d'Éloges. Le modernisme p orté par les Bla ncs européens divise blanc et non-blanc, gouvern ants et gouvernés, ains i que "nous" et "les autres". Enfin, nous étudions le poète lui-même comme un sujet de la diaspora, à travers la noti on de "l 'identité", une des plus importantes pour la géographie cultur elle contemporaine. N ous recherchons comment se forme-t-elle son identité c ulturelle dans la vie quotidienne aux îl es, société multi-ra ciale et multi-culturelle. Nous avons recours à l'analys e d' Images à Crusoé pour ap profondir le prob lème de l'identité segmentée du sujet de la di aspora qu i a immigré de la France aux Antilles, pour rep artir enfin pour la France. Nous faisons ainsi val oir que le recuei l Éloges est profondément lié aux sujets princi paux de la géographie culturelle contemporaine.

쥘 쉬페르비엘의 시에 나타난 지리적 상상력 : 여행과 정주, 새로운 세계

김시원(Si-Won KIM) 프랑스학회 2017 프랑스학연구 Vol.0 No.83

Au cours des derniéres décennies, la poésie française est caractérisée par «l’ouverture au monde», mise en relief par Michel Collot. Pourtant, pour ce qui est de cette tendance, nous nous intéressons moins à la jeune génération de poétes qu’à un de ses précurseurs de la premiére moitié du XXe siécle, Jules Supervielle. Chez celui-ci la poésie s’unit, en acceptant les diverses localités de pays lointains, à la géographie. La poésie superviellienne est remarquable non seulement pour son excellente véracité géographique mais aussi pour son imagination féconde géographique. L’expression «entre l Europe et l Amérique du Sud» s’accorde à la situation géographique, psychologique de Supervielle. Et comme suggére bien l’expression “Ulysse Montévidéen”, il rêve du retour à l’Amérique du Sud, sa véritable patrie. Par ailleurs, nous tentons d’interpréter son imagination géographique s’appuyant sur «la dialectique du voyage et de l’habitation» proposée par Kenneth White. Il s agit de l imagination par laquelle Supervielle s identifie à Christophe Colomb qui a quitté l Europe et découvert le Nouveau Monde. Son imagination géographique concerne alors moins la dimension biographique que celle d’historique et de collectif. En fait, son imagination géographique imprégne sa poésie d expérience historique des Pionniers qui ont exploité les terres inconnues, comme le montrent plusieurs de ses poémes. Chez ce poéte l Europe et l Amérique du Sud s’affrontent comme un lieu de départ et un lieu à atteindre. D’ailleurs, Supervielle représente son désir de traverser une distance interstellaire au lieu d une mer entre deux continents. Ce poéte-astronome qui rêve d un « nouveau monde » à travers le télescope astronomique serait le conquérant de l Univers qui porte déjà une «carte du ciel» dans son intérieur. Pourtant, Supervielle vise moins une conquête physique que la communication cosmique par laquelle il accueille tous les êtres dans l’Univers, s’approprie toutes les maisons cosmiques. Soit le nouveau continent, soit l’espace interstellaire, Supervielle l’aspire paradoxalement pour finir son errance. Il veut y atteindre pour une véritable installation et communication, en tournant le dos aux maisons européennes étroitement fermées.

수원 일월저수지에서 Microcystis aeruginosa (K$\ddot{u}$tzing) K$\ddot{u}$tzing 수화현상 시 환경요인들의 변화

김지은,박정원,조기안,김시균,Kim, Ji-Eun,Park, Jung-Won,Jo, Ki-An,Kim, Si-Kyoon 한국하천호수학회 2013 생태와 환경 Vol.46 No.2

본 연구는 수원 일월저수지에서 수화현상 시 환경요인들의 변화와 한국형 부영양화 지수를 이용하여 영양단계를 평가하였다. 수화현상 종은 남조류의 Microcystis aeruginosa Kutz.였으며 조사기간 내내 우점하였다. 수온은 평균 $25.7{\sim}28.4^{\circ}C$, pH는 8.4~11.17, CODcr는 4.25~$72.0mg\;L^{-1}$, 전기전도도는 333.1~$749.0{\mu}S\;cm^{-1}$, Chl-a는 22.0~$185.0mg\;L^{-1}$였다. 정체 수역인 정점 2에서 CODcr는 다른 정점에 비해 2.9배 정도로 높아 내부기원 유기물의 기여도가 높은 것으로 판단된다. 영양염인 TN은 평균 28.86~$56.75mg\;L^{-1}$, TP는 0.2~$1.24mg\;L^{-1}$로 매우 높았고, Fe는 0.11~$1.05mg\;L^{-1}$이었고, Si는 3.13~$7.46mg\;L^{-1}$이었다. TN과 TP는 일월저수지 내에 지속적으로 누적된 것으로 파악되었고, Fe도 높은 농도가 유지되었다. 한국형 부영양화지수는 37.19~147.22였다. 영양단계는 중영양에서 과영양 단계로 평가되었고, 같은 저수지 내에서도 시기 및 지점에 따라 영양단계가 다름을 나타내므로 많은 자료가 추적된다면 한국형 영양단계 분석은 저수지의 영양단계 분석 시 매우 유용하게 활용될 것으로 판단된다. Variances in environmental factors were followed in Ilwol reservoir, Suwon, during bloom of Microcystis aeruginosa (K$\ddot{u}$tzing) K$\ddot{u}$tzing, Cyanophtya from August to October, 2011. M. aeruginosa dominated the water column throughout the investigation period. The water temperature varied from $25.7^{\circ}C$ to $28.4^{\circ}C$, pH 8.40 to 11.17, CODcr 4.25 to $72.00mg\;L^{-1}$, electrical conductivity 333.1 to $749.0{\mu}g\;cm^{-1}$, and Chl-a 22 to $185mg\;L^{-1}$. In particular, the high levels of CODcr is likely indicate high contribution of autochthonous organic matters in the reservoir. TN varied from 28.86 to $56.75mg\;L^{-1}$, TP 0.20 to $1.24mg\;L^{-1}$, Fe 0.11 to $1.05mg\;L^{-1}$, and Si 3.13 to $7.46mg\;L^{-1}$. These increases imply constant accumulation in Ilwol reservior, and reinforce the idea of autochthonous organic matters input in the reservoir. The Korea Trophic Status Index ($TSI_KO$) varied from 37.19 to 147.22. Trophic levels varied from mesotrophic to hypertrophic level, and differed spatio-temporally. Therefore, it is concluded that $TSI_KO$ is useful for analyzing trophic status of reservoirs.

Xylanase와 CMCase의 생산성이 높은 Bacillus sp.의 분리 및 동정

김창원,송민동,정원형,양시용 건국대학교 동물자원연구센터 2000 動物資源硏究誌 Vol.21 No.-

CMCase와 xylanase를 동시에 분비하는 미생물을 얻기 위해 1차적으로 111균주를 분리한 후, 활성이 가장 우수한 1-5균주를 선발하였다. 선발된 균을 API 20과 API 50 CHB kit를 이용하여 동정한 결과 Bacillus licheniformis로 동정되었다. Nutrient broth를 배양배지로 하여 growth와 효소역가를 측정한 결과 cell growth growth는 20시간 후에 stationary phase에 도달하였으며 xylanse는 8시간 배양 후 최대의 역가를 나타냈고, CMCase는 28시간 후 최대의 역가를 나타냈다. A bacterium producing xylanase and CMCase was isolated from soil, has been identified as Bacillus sp. The isolate, named Bacillus sp.1-5, was shown to be very similar to Bacillus licheniformis on the basis of its biochemical and physiological properties. In culture time, xylanase and CMCase production reached to the plateau after 8hr and 28hr of cultivation in the nutrient broth.