• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권1호
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• pp.30-33
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• 2006

Transparent indium tin oxide (ITO) anode surface was modified using $O_3$ Plasma and organic ultrathin buffer layers were deposited on the ITO surface using 13.56 MHz RF plasma polymerization technique. The EL efficiency, operating voltage and lifetime of the organic light-emitting device (OLED) were investigated in order to study the effect of the plasma surface treatment and role of plasma polymerized organic ultrathin buffer layer. Poly methylmethacrylate (PMMA) layers were plasma polymerized on the ITO anode as buffer layer between anode and hole transport layer (HTL). The plasma polymerization of the organic ultrathin layer were carried out at a homemade capacitive-coupled RF plasma equipment. N,N'-diphenyl-N,N'(3- methylphenyl)-1,1'-diphenyl-4,4'-diamine (TPD) as HTL, Tris(8-hydroxyquinolinato) Aluminum $(Alq_3)$ as both emitting layer (EML)/electron transport layer (ETL), and aluminum layer as cathode were deposited using thermal evaporation technique. Effects of the plasma surface treatment of ITO and plasma polymerized buffer layers on the OLED performance were discussed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1347-1348
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• 2007

In this paper, ITO gate electrode surface was modified using $O_2$ plasma and organic gate insulating layers were deposited on the ITO surface using plasma polymerization technique. In order to investigate the influence of the plasma coupling method and plasma conditions on the plasma polymerized methyl methacrylate (ppMMA) thin film properties, inductively coupled (ICP) and capacitively coupled plasma (CCP) were used to generate the plasma and the plasma parameters were varied. The ppMMAs were investigated using atomic force microscopy (AFM) and a Fourier Transform Infrared (FT-IR) spectroscopy. Dielectric constants of the ppMMA thin films were investigated using a impedance analyzer (HP4192A, LF Impedance Analyzer). Current-Voltage (I-V) characteristics of the organic thin film transistors (OTFTs) were investigated using a source measurement unit (SMU: Keithley 2612). Proposed method can be applied to dry-process to fabricate OTFTs during overall fabricating steps.

• Bulletin of the Korean Chemical Society
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• 제7권3호
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• pp.196-200
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• 1986

The solvent change and salt do not affect the fluorescence quantum yield of 1,3-dimethylnaphtho[1,2-e]uracil indicating the considerable energy gap between the lowest singlet $({\pi},\;{\pi}^{\ast})\;and\;(n,\;{\pi}^{\ast})$ states in the compound. The results are consistent with the strong quenching of fluorescence by ethyl iodide. Fluorescence quantum yield is nearly independent of temperature, probably due to the relatively inefficient internal conversion. Unusual spectral difference is observed in isopentane and ethanol at 77K. The temperature dependence of emission in isopentane and in ethanol suggests that the increase of charge transfer character by the conformational change in isopentane leads to the structureless and red-shifted fluorescence, while in ethanol the decrease of the charge transfer character by the hydrogen bonding interaction results in the structured and blue-shifted fluorescence along with phosphorescence at the low temperature. Temperature dependence of emission in poly(methylmethacrylate) matrix indicates that $T_1{\to}S_0$ radiationless decay is an important process responsible for the strong temperature dependence of phosphorescence.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제12권1호
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• pp.171-179
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• 1990

This is a report on a case of delayed reconstruction after partial mandibularectomy for Ameloblastoma involving symphysis and bodies of the mandible by using of two large pieces of corticocancellous bone blocks obtained from both iliac crests. The authors failed immediate reconstruction with two kinds of Alloplasts(metal, methylmethacrylate) at two times of trial due to known infection and suggestive poor histocompatibility of materials aginst the host who has been suffered from long-term and active pulmonary tuberculosis. However we could get success late reconstruction of this problem-occured and curved area with two pieces of large corticocancellous blocks by using of miniplate osteosynthesis and biphasic external pin fixation. From our experience we are obtained some results as follows : 1. Alloplastic graft materials seemed to be dangerous to maintain successfuly in patient who has a long-term debilitating disease as a active pulmonary tuberculosis. 2. Biphasic external skeletal pin fixation appliance gave many advantages such as maintain functional position of the remained bodies and condyles of the mandible after removal of failed alloplasts and during control of inflammation of this area, assist supportive roles to fix and maintain bone grafts during healing, allow mandibular movement during healing and so offer to conduct normal functional stimuli to bone grafts during osteogenesis etc. 3. Bony union was successful between not only normal bones and grafted bones but also grafted bone pieces even though we used two pieces of large blocks of corticocancellous bone for graft. 4. Miniplate osteosynthesis was not affect any adverse effects to bone grafts but offered good role of fixation and maintenance for bone grafts.

• 접착 및 계면
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• 제11권4호
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• pp.174-180
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• 2010

다중벽탄소나노튜브를 표면처리하여 polymethylmethacrylate (PMMA) 기재에 첨가하여 제조한 고분자 복합재료에서 탄소나노튜브의 표면처리가 계면 및 열전도도에 미치는 효과를 고찰하였다. Coagulation 방법과 atomic transfer radical polymerization (ATRP) 방법을 사용하여 탄소나노튜브를 표면 처리 하여 사용하였으며, ATRP 방법을 적용하여 제조한 복합재료는 coagulation 방법을 사용하여 제조한 복합재료보다 높은 열전도도와 투과도를 가졌다. 순수 PMMA의 열전도도가 0.21 W/mK인데 비하여 ATRP 방법으로 처리한 1 wt%의 탄소나노튜브를 첨가하였을 경우 0.38 W/mK로 열전도도가 향상되었다. 탄소나노튜브와 PMMA기재의 계면을 주사전자현미경을 이용하여 관찰한 결과 탄소나노튜브의 표면처리에 의해 기재 내에 분산이 향상되고 고분자기재-탄소나노튜브 계면에서의 접촉이 용이해져 포논산란이 감소되어 광 투과성을 가지면서 열전도도가 향상된 것으로 보인다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.366-366
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• 2012

무기물 나노입자를 포함한 유기 박막인 나노 복합체를 사용하여 제작한 비휘발성 메모리 소자는 공정의 간단함과 낮은 전력구동이 가능하다는 장점 때문에 차세대 비휘발성 메모리 소자로 각광받고 있다. 다양한 나노입자를 포함한 유기 박막을 사용한 비휘발성 메모리 소자에 대한 연구는 많이 진행되었지만, 코어-쉘 나노입자가 poly (methylmethacrylate) (PMMA) 유기 박막에 분산되어 있는 나노 복합체를 활성층으로 사용하여 제작한 비휘발성 유기 메모리 소자의 전기적 특성과 메모리 메커니즘에 대한 연구는 비교적 미미하다. 본 연구에서는 코어-쉘 나노 입자가 PMMA 박막 안에 분산되어 있는 나노복합체를 사용한 비휘발성 메모리 소자를 제작하여 전기적 특성, 정보 유지력 및 메모리 스위칭 동작에 대하여 관찰 하였다. 소자 제작을 위해 hexane 안에 들어 있는 코어-쉘 나노입자를 Chlorobenzene에 용해되어 있는 PMMA에 넣어 초음파 교반기를 사용하여 나노입자를 고르게 분산하였다. 코어-쉘 나노입자가 PMMA에 고르게 분산 된 용액을 전극으로 사용 할 Indium-tin-oxide가 성장된 glass 위에 스핀코팅을 한 후 열처리를 하여 용매를 제거한 후 코어-쉘 입자가 PMMA에 분산되어 있는 박막을 형성하였다. 코어-쉘 입자가 PMMA에 분산된 나노복합체 위에 Al을 상부전극으로 열 증착하여 비휘발성 메모리 소자를 제작하였다. 제작된 소자의 전류-전압 (I-V) 특성을 측정결과는 특정한 두께에서 낮은 전도도 (ON state)와 높은 전도도 (OFF state)가 존재하는 쌍안정성 특성을 확인하였다. 코어-쉘 나노입자가 포함되지 않은 소자에서는 쌍안정성 특성이 보이지 않아 코어-쉘 나노입자가 비휘발성 메모리 소자의 기억 특성을 나타내는 중요한 저장 매체가 됨을 알 수 있었다. 제작된 메모리 소자의 메모리 동작에 대한 메커니즘 설명은 I-V와 에너지 밴드 구조를 사용하여 설명할 것이다.

• 대한골관절종양학회지
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• 제1권1호
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• pp.52-59
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• 1995

Metastatic cancer is the most common tumor of the skeleton. The prevalence of pathologic fracture may increase as patient survival is prolonged by improved cancer therapy. With recent advances in orthopaedic procedure and medical management of terminal cancer patients, it is generally agreed that aggressive treatment should be undertaken for patient with pathologic fracture secondary to metastatic disease, and a team approach should be utilized. The authors have reviewed twenty cases of pathologic fracture of the long bone due to metastatic tumor treated in the Department of Orthopedic Surgery, Yonsei University College of Medicine, from April 1989 to April 1994 and the following results were obtained. 1. The mean age at surgery was 58.4 years (ranged from 24years to 86years) and among 20 cases, 10 cases were male and the others were female. 2. The most frequent site of pathologic fracture in long bone is femur(15 cases, 75%), and followed by humerus(4 cases, 20%), tibia(1 case). 3. The frequently encountered primary tumors that metastases to long bone are those of the lung(7 cases, 35%), breast(4 cases, 20%), and prostate(2 cases, 10%). 4. The operative procedure was performed by resection of the tumor mass extensively, and we used polymethylmetacrylate for filling the dead space after resection, in all cases. 5. The mean survival period after operation is 9.2 months(ranged from 1 month to 4 years and 9 month). 6. The results of postoperative pain relief status were graded as fair to excellent in 17 cases(85%).

• 폴리머
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• 제34권2호
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• pp.154-158
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• 2010

$\alpha$,$\omega$-Dichlorohexamethyltrisiloxane의 aniline과 고리 반응으로부터 N-phenylcyclotrisiloxazane($D_3^{NPh}$)을 합성하고 이를 hexamethylcyclotrisiloxane$D_3$과 이온 공중합시켜 poly(dimethylsiloxane-co-N-phenylsiloxazane)공중합체(PDMS-NPSOX)를 제조하였다. 이를 chloroethyl methacryalte에 도입하여 PDMS-NPSOX unit가 도입된 아크릴 단량체를 제조하였으며, 이를 MMA 및 n-butyl acrylate와 공중합시켜 PDMS-NPSOX가 도입된 삼원 아크릴 공중합체를 제조하고, 그 특성을 조사하였다. 단량체 조성은 생성 공중합체의 $T_g$가 25 $^{\circ}C$가 되도록 선택하여 공중합시켰다. 공중합체에서 PDMS만 도입된 경우 $T_g$가 20 $^{\circ}C$인데 비하여 PDMS-NPSOX unit이 도입됨에 따라 25 $^{\circ}C$로 증가되었으며 접착력도 1.76 N/cm에서 2.23 N/cm로 증가되었다.

• Archives of Plastic Surgery
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• 제33권5호
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• pp.659-662
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• 2006

Purpose: Alloplastic implants, such as methylmethacrylate, Teflon, silicone, Supramid are commonly used to cover the floor defect and to prevent reherniation of the displaced orbital tissue in orbital floor fracture. Silicone implant has been used for reconstruction of orbital wall defects because of pliability, advantage of carving and chemically inert nature. However, silicone implant also has complications including infection, extrusion, pain, dystopia and tissue reaction. Cyst formation around the silicone implant is a very rare complication. According to many reports, cysts around alloplastic implant in an orbital area are mostly hemorrhagic cysts consisted of blood breakdown product with fibrous capsule cell in histologic examination. Methods: The authors report atypical case and successful treatment of intraorbital hemorrhagic cyst around silicone implant of a 37-year-old male patient. Results: Preoperative symptoms of diplopia, exophthalmos, proptosis, vertical dystopia and ectropion of lower eyelid were resolved after surgical removal of implants with surrounding capsule. Conclusion: Clinical suspicion of plastic surgeon is important in diagnosis of intraorbital cyst of patients who have history of silicone implantation and computed tomography is the standard tool of diagnosis. During the operation, caution must be taken on delivering the whole capsule of intraorbital cyst along with silicone implant to prevent recurrence of the cyst.

• Journal of Chest Surgery
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• 제30권3호
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• pp.348-348
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• 1997

48세 남자 환자의 전종격동을 깊게 침범하며 흉골에서 발생한 거대한 연골육종을 치료하였다. 환자는 흉골의 연골육종과 주변의 정상변연 4cm을 포함하여 광범 위 절제술을 받았으며 그 종양 자체 는 양측의 쇄골과제 1,2,3늑연골을 포함하는 15× 16X10cm크기였다. 종양의 광범위 절제술후 남은 결손 부위는 매우 컸으며 흉벽 재건술을 Marled mesh와 methylmethacrylate와 wire steels로 겹싸는 sandwich식의 방법으로 시행하였고 연부조직의 재건술 또한 대흉근을 이용한 근피 판 치환술을 시행하 였다. 그러나 환자는 수술후 결핵성 종격동염이 발생되었고 다량의 농이 배출되었다. 재수술은 흉벽 재건술시의 사용되었던 이물질 모두를 제거하고 괴사성 조직의 소파술과 배농술을 시행하였다. 환자는 1 년간 항결핵제요법을 시행하였으며 완치되었기에 문헌고찰과 보고하는 바이다.