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>

Improved Adhesion of Metal Electrode Layer on Si₃N₄ Substrate through an All-Wet Process

Kim, Danbi,Eom, Nu Si A,Kim, Jiwon,Lee, Kyu Hyoung,Park, Sung Heum,Lee, Ju Ho,Chao, Yong-Ho,Lim, Jae-Hong Electrochemical Society 2019 ECS journal of solid state science and technology Vol.8 No.2

<P>Electroless deposition requires preliminary surface treatment to effectively adsorb a metal electrode layer onto a ceramic substrate. Herein, a simple surface treatment using an all-wet process was performed to achieve adhesion stability between a Si<SUB>3</SUB>N<SUB>4</SUB> substrate and Ni film. The method involved deposition of an interfacial Pd-TiO<SUB>2</SUB> buffer between the two layers. Surface pretreatment via silanization was initially performed to improve surface wettability, thereby enhancing uniform deposition of Pd-TiO<SUB>2</SUB>. Subsequently, a thin Ni layer was directly deposited onto the Pd-TiO<SUB>2</SUB> layer without necessitating sensitization or activation. The synthesized Ni/Pd-TiO<SUB>2</SUB>/Si<SUB>3</SUB>N<SUB>4</SUB> heat sink exhibited excellent adhesion property in the cross-hatch, scratch, and thermal shock tests. The mechanism of adhesion enhancement involved chemical bonding of Pd-TiO<SUB>2</SUB> with the self-assembled monolayer on the substrate and reduced internal stress due to removal of residual hydrogen between the layers of the heat sink. Thus, the fabricated heat sink has a promising application in electronic devices operated at high temperatures.</P>

A Study on Improvement and Degradation of Si/SiO₂ Interface Property for Gate Oxide with TiN Metal Gate

Lee, Byung-Hyun,Kim, Yong-Il,Kim, Bong-Soo,Woo, Dong-Soo,Park, Yong-Jik,Park, Dong-Gun,Lee, Si-Hyung,Rho, Yong-Han The Korean Institute of Electrical and Electronic 2008 Transactions on Electrical and Electronic Material Vol.9 No.1

In this study, we investigated effects of hydrogen annealing (HA) and plasma nitridation (PN) applied in order to improve $Si/SiO_2$ interface characteristics of TiN metal gate. In result, HA and PN showed a positive effect decreasing number of interface state $(N_{it})$ respectively. After FN stress for verifying reliability, however, we identified rapid increase of $N_{it}$ for TiN gate with HA, which is attributed to hydrogen related to a change of $Si/SiO_2$ interface characteristic. In contrast to HA, PN showed an improved Nit and gate oxide leakage characteristic due to several possible effects, such as blocking of Chlorine (Cl) diffusion and prevention of thermal reaction between TiN and $SiO_2$.

서울의 Penicillinase Producing Neisseria Gonorrhoeae 발생빈도(1994)

김재홍,안진균,정성재,김영태,김중환,김시영,이석종,이홍렬,서호석,김경훈,권혁진,정우권,고우석,이용석,안필수,오준규,오용섭 대한화학요법학회 1996 대한화학요법학회지 Vol.14 No.1

Background : In recent years gonorrhoea has been panendemic and remains one of the most common Sexually Transmitted Diseases in the world, especially in developing countries. Objective & Method : For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria Gonorrhoeae(PPNG), Ive have been trying to study the patients who have visited the VD Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results : In 1994, 168 strains of N. gonorrhoeae were isolated, among which 109 (64,9% ) were PPNG. Conclustion : Our results suggests that the prevalence of PPNG in Seoul is still increasing.

A Study on Improvement and Degradation of Si/SiO2 Interface Property for Gate Oxide with TiN Metal Gate

이병현,Yong-Il Kim,Bong-Soo Kim,Dong-Soo Woo,Yong-Jik Park,Dong-Gun Park,Si-Hyung Lee,Yonghan Rho 한국전기전자재료학회 2008 Transactions on Electrical and Electronic Material Vol.9 No.1

In this study, we investigated effects of hydrogen annealing (HA) and plasma nitridation (PN) applied in order to improve Si/SiO₂ interface characteristics of TiN metal gate. In result, HA and PN showed a positive effect decreasing number of interface state (Nit) respectively. After FN stress for verifying reliability, however, we identified rapid increase of Nit for TiN gate with HA, which is attributed to hydrogen related to a change of Si/SiO₂ interface characteristic. In contrast to HA, PN showed an improved Nit and gate oxide leakage characteristic due to several possible effects, such as blocking of Chlorine (Cl) diffusion and prevention of thermal reaction between TiN and SiO₂.

항정신병약물 사용 중인 정신분열병 환자에서 올란자판으로의 교체 방법에 관한 연구(II) : Comparison of Safety 안전성 비교

안용민,권용실,권준수,민성호,박두병,양문정,소형석,송종호,신윤식,우행원,유범희,이홍석,정한용,한창환,김용식 大韓神經精神醫學會 2002 신경정신의학 Vol.41 No.5

연구목적: 이 다기관 공동임상연구는 사용 중인 항정신병약물을 ’직접 교체 방법’또는 ’시작-감량 교체 방법’중 한 가지 방법으로 올란자핀으로 교체한 후, 안정성 측면에서 두 교체 방법 간의 비교와 교체후의 변화를 관찰하기 위한 것이다. 방법: 국내 13개 병원의 입원 및 외래에 내원한 환자들 중 ICD-10 지단기준으로 정신분열병에 해당되며, 임상적으로 항정신병약물 교체가 필요한 환자를 대상으로 하였다. 두 가지 교체 방법 중 한 가지를 무작위로 피험자에 적용하였으며, ’직접 교체 방법’에 배정된 경우에는 사용중인 항정신병약물을 일시에 중단하고 10㎎의 올란자핀을 바로 투여하였고, ’시작-감량 교체 방법’에 배정된 경우는 10㎎의 올란자핀 투여하고 2주에 걸쳐서 기존 약물을 감량하여 중단하였다. 올란자핀 사용기간은 총 6주이며, 용량은 5∼20㎎ 범위로 제한하였다. 한정성 평가를 위해서 체중, 생명징후, 자발적인 이상반응 복, 실험실 검사 그리고 Simpson-Angus Scale(SAS), Barnes akathisia rating scale(BARS), Abnormal involuntary movement scale(AIMS). Liverpool University neuroleptic side effect rating scale(LUNSERS)등을 이용하였다. 결과: 총 103명의 정신분열병 환자를 대상으로 하였다. 사용한 올란자핀의 용량, 벤조디아제핀의 병용률, 탈락률과 탈락 사유, 자발적인 이상반응 보고, 생명징후, 실험실 검사 그리고 대부분의 부작용 척도 상에서 임상적으로 의미 있는 차이를 두 교체 방법간에 발견하지 못하였다. 다만 AIMS의 감소는 ’직접 교체 방법’군에서 보다 적었고, 항콜린제의 병용률은 ’시작-감량 교체 방법’군에서 보다 많았다. 기저 상태에서 전체 피험자의 SAS와 BARS 점수는 각각 3.5점과 1.8점이었으며 70% 이상의 피험자가 고프로락틴 혈증을 보였다. 올란자핀으로 교체한 후, SAS, BARS, AIMS 점수의 유의한 감소가 있었으며 고프로락틴 혈증을 보인 피험자 분율도 약 30%이하로 감소하였다. 그러나 교체 방법과 상관없이 올란자핀 교체 후 유의한 체중 증가가 있었다. 결론: 이 연구를 통해 교체 방법에 관계없이 비교적 안전하고 용이하게 올란자핀으로 교체 할 수 있음을 알 수 있었다. 그리고 기존 항정신병약물을 올란자핀으로 교체함으로써 일부 부작용들을 줄일 수 있음을 간접적으로 관찰할 수 있었다. 하지만 이 연구는 여러 제한점과 문제점을 지니고 있기 때문에 보다 체계적인 연구를 통해 검정이 필요하리라 생각된다. Objectives: This multicenter clinical trial involving 13 hospital sites compared the safely of switching to olanzapine between ’direct switching method’ and ’start-tapering switching method’. Method: This study included both inpatients and outpatients who fulfilled the criteria for schizophrenia as defined in the ICD-10, and were in need to be appropriate for switching antipsychotics. Subjects were randomly assigned to one of the two switching methods. For ’direct switching method’group, previous antipsychotics were abruptly discontinued and 10㎎ of olanzapine was administered, and previous antipsychotics was gradually tapered for 2 weeks. Olanzapine was used for 6 weeks and the dose was adjusted within the range of 5-20㎎. The safety of switching to olanzapine was measured with vital sings including body weight, adverse events reported spontaneously, laboratory tests, and various scales such as Simpson-Angus Scale(SAS), Barnes Akathisia Rating Scale(BARS). Abnormal Involuntary Movement Scale(AIMS), and Liverpool University Neuroleptic Side Effect Rating Scale(LUNSERS). Results: 103 patients were switched to olanzapine in this study. The comparison between two switching methods did not show any significant difference in the dosage of olanzapine used, the concomitant use of benzodiazepine, the rate and reasons of drop-out, the adverse events, vital signs, laboratory tests, and most scales for measuring side-effects. However, the decrease in AIMS scores was significantly lower in ’direct switching method’ group, and the concomitant use of anticholinergics was comparatively greater in ’start-tapering switching method’ group. At baseline, SAS and BARS scores were 3.5 and 1.8 points respectively, and more than 70% of the subjects showed hyperprolactinemia. After switching to olanzapine, SAS, BARS, and AIMS scores were significantly decreased and the proportion of the patients with hyperprolactinemia was also decreased to less than 30%. However significant weight gain after the treatment of olanzapine was observed regardless of switching method. Conclusion: This study may suggest that switching to olanzapine can be done with relatively high safety regardless of switching methods and olanzapine can significantly decrease some side-effects induced by other antipsychotics.

Chitosan의 단백질 흡착에 관한 연구

金容旭,車時煥 慶熙大學校 1989 論文集 Vol.18 No.-

Chitosan is a collective term applied to deacetylated chitin in various stages of deacetylation arid depolymarization. Chitosan solution has been shown to be on effective agent for coagulation of suspended solids in various food processing wastes, including poultry egg, soy-milk processing waste. Chitosan is insoluble in water, alkalis and organic solvents but soluble in many dilute aqueous organic acids at concentration in the range of 0.25 to 10%. Viscosity was determined for same chitosan solution over the temperature range 20℃ to 45℃ and the time range 1 to 5. The purpose of this studies has been shown to be on effective agent for coagulation of suspended solids in various food-processing waste water, including egg and milk processing waste water. Treatment with chitosan and removal of the coaglated by gravity settling or dissolved air flotation typically resulted in suspended solids reductions of over 90%. We believe that because chitosan is derived from a natural product and composed of biodgradable structures, it may prove useful in the recovery of coagulated by-products from food-processing waster. Where these by-products will be recycles into animal feeds.

발열체를 가진 2중 수평채널에서의 전열특성에 관한 연구

김동균,박용진,배석태,김시범 동아대학교 생산기술연구소 2000 生産技術硏究所硏究論文集 Vol.5 No.1

In this study was performed on the characteristics of heat transfer analysis by numerical method in a double horizontal channel with internal heat sources, up and down side walls are adiabatic condition. Pseudo PCB(Printed Circuit Board) with cooling hole its located around heat source. This channel have two heat sources that its condition is uniform heat flux maintenance 5W, upper channel and lower channel inlet velocity 0.2m/sec and outlet open condition. Parameter is cooling hole's location on the plate(PCB) and increasing heat flux(10W,15W) for one case.

한국기업의 M&A에 의한 해외진출전략에 관한 연구 : 대미 · 대EU M&A 사례를 중심으로

김지용,한시환 동국대학교 경제경영연구원 1998 國際貿易硏究 Vol.22 No.2

성인 만성 부비동염에서 내시경적 부비동 수술 전·후의 증상 호전도와 음향비강통기도 검사 결과

김용대,김재열,장근영,이형중,송시연,윤석근 영남대학교 의과대학 2002 Yeungnam University Journal of Medicine Vol.19 No.1

Background: Chronic paranasal sinusitis is one of the most common disease in the otorhinolaryngologic field. Endoscopic sinus surgery is treatment of choice in chronic paranasal sinusitis. The aim of this study was to evaluate objective and subjective treatment outcomes of endoscopic sinus surgery in adult chronic paransal sinusitis with or without polyp. Materials and Methods: We reviewed 84 adult patients underwent endoscopic sinus surgery by one surgeon from June 1999 to June 2000, prospectively. We analyzed preoperative and postoperative subjective symptom scores and acoustic rhinometric results. Results: Fifty cases were male and thirty four cases female. The average age was of 33 year-old (range: 17 to 66 years). There was significantly improvement of symptom scores in postoperative 3 months and 6 months compared with preoperative symptom scores. There was significantly increased postoperative total volume of nasal cavity. When we compared high score group with low score group, there was statistically significant improvement of symptom scores between preoperative stage and postoperative 3 months in radiologic grading group. Conclusion: Endoscopic sinus surgery is considered to be effective for the treatment of chronic paranasal sinusitis. It seems to be helpful to employ subjective symptom score system and objective total volume change of nasal cavity through acoustic rhinometric test to analyze effectiveness of endoscopic sinus surgery. In this study, the most important preoperative factor of sinus surgery outcomes is radiologic grading system.