• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.629-632
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• 1999

For replacing Li metal ai Lithium ton Bakery(LIB) system. we used carbon powder material which prepared by pyrolysis of phenol resin as starting material. It became amorphous carbon by pyrolysis through it\`s self condensation by thermal treatment. Amorphous carbon can be doped with Li intercalation and deintercalation because it has wide interlayer. however it has a problem with structural destroy causing weak carbon-carbon bond. So. we used ZnCl$_2$ as the pore-forming agent. This inorganic salt used together with the resin serves not only as the pore-forming agent to form open pores, which grow Into a three-dimensional network structure in the cured material, foul also as the microstructure-controlling agent to form a loose structure dope with bulky dopants. We analyzed SEM in order to find to different of structure. and can calculate distance of interlayer. CV test showed oxidation and reduction

• 펄프종이기술
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• 제43권3호
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• pp.106-112
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• 2011

The effects of alkaline treatment on the WRV, crystalline structure and sheet structure of softwood and hardwood bleached kraft pulp were investigated. Sodium hydroxide and sodium carbonate were used as chemicals for alkaline treatment and two levels of alkali dosage (5%, 10%) were applied respectively. Alkali treated and untreated pulp were refined to three levels (550, 450 and 350 mL CSF). WRV of the alkali treated pulps depended on the alkaline type and concentration. It was found that the crystalline structures of softwood and hardwood pulp were not changed by refining. Sodium carbonate and lower concentration of sodium hydroxide treatment did not caused any modification of cellulose crystalline structure, while higher concentration of sodium hydroxide treatment caused the partial modification of cellulose crystalline structure. Alkaline treatment of hardwood bleached kraft pulp led to the shrinkage of fiber diameter and bulky structure of sheet. Alkaline treatment of softwood bleached kraft pulp did not cause the significant change in fiber shrinkage and bulk of sheet.

• Molecular & Cellular Toxicology
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• 제3권2호
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• pp.145-149
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• 2007

Studies of relationship between structure and toxicity of azo dyes have been performed with comparative molecular field analysis (CoMFA) techniques. 3D QSTR analyses indicate that the steric and electrostatic interactions are important. The steric field based model gives strong correlation ($q^2$=0.57, $r^2$= 0.92). The steric field in conjunction with electrostatic field give more strong correlation ($q^2$=0.57, $r^2$=0.95). All study indicates that a bulky and electronegative group at benzene ring and a small group at position 3 of aniline ring might be significant to reduce the mutagenicity.

• 전력전자학회논문지
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• 제22권6호
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• pp.510-516
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• 2017

This paper proposes a single-stage interleaved totem-pole on-board battery charger with a simple structure and a reduced component count. Apart from achieving ZVS turn-on of all switches and ZCS turn-off of all diodes, this charger does not require an input filter due to its CCM operation and bulky electrolytic capacitors, which in turn result in a high power density. A single-stage power conversion technique is applied to the interleaved structure in order to achieve a high power density and high efficiency. A 2.5 kW prototype of the proposed charger is also built and tested to validate the proposed operation.

• Smart Structures and Systems
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• 제4권3호
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• pp.305-318
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• 2008

The development of a digital signal processor based prototype is described in relation to continuing efforts for realizing a fully self-contained active sensor system utilizing impedance-based structural health monitoring. The impedance method utilizes a piezoelectric material bonded to the structure under observation to act as both an actuator and sensor. By monitoring the electrical impedance of the piezoelectric material, insights into the health of the structured can be inferred. The active sensing system detailed in this paper interrogates a structure utilizing a self-sensing actuator and a low cost impedance method. Here, all the data processing, storage, and analysis is performed at the sensor location. A wireless transmitter is used to communicate the current status of the structure. With this new low cost, field deployable impedance analyzer, reliance on traditional expensive, bulky, and power consuming impedance analyzers is no longer necessary. A complete power analysis of the prototype is performed to determine the validity of power harvesting being utilized for self-containment of the hardware. Experimental validation of the prototype on a representative structure is also performed and compared to traditional methods of damage detection.

• 한국응용과학기술학회지
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• 제21권1호
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• pp.24-30
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• 2004

New electroluminescent materials based on anthracene chromophore with naphthylethenyl substituent, 9,10-bis($\alpha$-naphthylethenyl)anthracene (a-BNA), as well as four kinds of its derivatives were synthesized, and luminescent properties of these materials were investigated. Electrolumineecent(EL) emission band was discussed based on their substituent structure differences. It was found that the emission band strongly depends on the molecular structure of introduced substituent. It can be tuned from 557 nm to 591 nm by changing the substituent structures. On the other hand, the anthracene chromophore with bulky substituent possessed high melting point and they gave stable films through vacuum-sublimation. The double layer EL device of ITO/TPD/emission layer/Mg:Ag was employed, and exhibited efficient orange light originating from emitting materials. EL emission with a maximum luminance was observed in the b-BNA emitting material, : maximum luminance was about 8,060 cd $m^{-2}$ at an applied voltage of 10 V and current density of 680 $mA/cm^2$. In conclusion, the electroluminescent properties also showed good difference with their substituent structure.

• Archives of Pharmacal Research
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• 제14권2호
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• pp.137-142
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• 1991

The structure of a $\beta$-allyl type phenylpropanoid was determined by single crystal X-ray diffraction analysis. The compound was recrystallized from a mixture of n-hexane and benzene in monoclinic crystal system with a = 24.782 (2), b = 10.537 (1), c = 7.871 (1) ${\AA}, \beta=95.74$ (1)$^\circ, $D_x$=1.216, $D_m$=1.22g/$cm^3$, space group $P2_1/a$, and Z=4. The structure was solved by direct method and refined by least-squares procedure to the final R value of 0.054 for 2824 observed reflections {$F{\geq}3\sigma(F)$}. The molecular geometry shows a most stable trans-form with respect to the bulky phenyls, and this conformation is settled by an intramolecular hydrogen bond. In the crystal, the molecules are arranged along with the screw axis, and stabilized by the $O{\cdot}H{\cdots}O$ type intermolecular hydrogen bonds. The other intermolecular contacts appear to be the normal van der Waals' interactions. The compound is a dimeric phenylpropanoid, and belongs to the neolignan analogues.

• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.335-338
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• 2008

New efficient red emitter having short p?-conjugation length and asymmetric bulky structure, 2-(7-diphenylamino-benzo[1,2,5]thiadiazole-4-ylmethylene)-malononitrile, was synthesized and characterized. Using this material as a dopant, we fabricated electroluminescence device with a structure of ITO/DNTPD/NPD/BTZA (5 wt% in Alq3)/Alq3/LiF/Al. The device exhibited a high brightness of 761 cd/m2 at a driving voltage of 4.8 V, and current efficiency is 0.75 cd/A. The Commission International de IEclairage (CIE) coordinates of the EL device were found to be (0.62, 0.37) at 10 mA/cm2.

• 박물관보존과학
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• 제22권
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• pp.27-40
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• 2019

국무회의 관련 기록(이하 '국무회의록')은 대한민국 정부의 중요 활동을 파악할 수 있는 기록물이다. 중요 자료인 국무회의록을 보존하기 위하여 국가기록원에서는 다양한 보존업무를 추진해왔다. 보존상자 맞춤 제작, 탈산 처리, 이중매체 보존(마이크로필름 촬영), 콘텐츠 디지털화(스캐닝) 등을 진행하였다. 2,000권이 넘는 국무회의록을 효과적으로 보존하기 위하여 상태검사 결과를 활용하여 보존처리 계획을 2018년에 수립하였다. 복원대상 97권 중 6권에 대한 보존처리를 끝내고, 그 처리사례를 소개하고자 한다. 국무회의록은 평균 800면이 넘는 기록물 철로 다른 기록물보다 편철이 거대한 기록물이 많다. 본고에서는 이러한 형태 때문에 생기는 구조적인 문제를 해결하기 위한 조치들을 중점적으로 소개한다. 물리적 원형이 확립되지 않은 종이 기록물에 대한 보존처리 접근 방법을 고찰하는 계기가 되기를 기대한다.

• 공업화학
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• 제10권3호
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• pp.427-431
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• 1999

알루미늄 혹은 철판의 코일 코팅 (coil coating) 공정에 사용되는 기본 수지인 copolyester의 중합 방법 맞 생성된 copolyester의 분자량, 열적 성질 및 용해 특성에 대해 조사를 하였다. Copolyester 수지의 합성은 1단계 반응에서 bishydroxyethyl terephthalate (BHET). bishydroxyneopentyl tereph-thalate (BHNPT), bishydroxyethyl isophthalate (BHEI), bishydroxyneopentyl sebacate (BHNPS), bishydroxyncopentyl adipicate (BHNPA), bishydro-xyethyl adipicate (BHEA) 올리고머를 esterification 반응을 통해 얻고 이들을 적정 mole 비로 혼합한 다음 polycondensation 반응을 시키는 2단계 반응으로 진행시켜 GPC로 측정된 중량 평균 분자량이 30,000~59,000 g/mole의 범위에 있는 비교적 고분자량의 copolyester를 얻을 수 있었다. 합성된 copolyester 시료들은 모두 $T_m$을 냐타내지 않아 비결정성 수지임을 알 수 있었고 이것은 고분자 주쇄 내에 kink 구조를 유발하는 BHEI와 bulky 한 neopentyl 연결기를 가지는 BHNPT, BHNPS와 같은 올리고머를 포함하는데 기인한 것으로 생각되었다. Copolyester 시료 중에서 BHEI (0.3 mole), BHNPS (0.1 mole) 올리고머를 같은 비율로 유지하고 BHET의 약 반 정도를 benzene 환 내에 같은 para 연결 구조를 가지나 bulky한 neopentyl glycol로 치환된 BHNPT로 바꾸어줌으로서 $40^{\circ}C$ 이상의 비교적 높은 $T_g$를 유지하면서 상온 및 서온 ($-5^{\circ}C$)에서 톨루엔 용매에 용해성이 높은 copolyester 수지를 얻을 수 있었다.