• 한국세라믹학회지
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• 제32권7호
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• pp.809-816
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• 1995

Ti1-xAlxN films were successfully deposited on high speed steel and silicon wafer by plasma-assisted chemical vapor deposition using a TiCl4/AlCl3/N2/Ar/H2 gas mixture. Plasma process enabled N2 gas to nitride AlCl3, which is not possible in sense of thermodynamics. XPS analyses revealed that the deposited layer contained Al-N bond as well as Ti-N bond. Ti1-xAlxN films were polycrystalline and had single phase, B1-NaCl structure of TiN. Interplanar distance, d200, of (200) crystal plane of Ti1-xAlxN was, however, decreased with Al content, x. Al incorporation into TiN caused the grain size to be finer and changed strong (200) preferred orientation of TiN to random oriented microstructure. Those microstructural changes with Al addition resulted in the increase of micro-hardness of Ti1-xAlxN film up to 2800Kg/$\textrm{mm}^2$ compared with 1400Kg/$\textrm{mm}^2$ of TiN.

• Pediatric Infection and Vaccine
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• 제19권2호
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• pp.61-70
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• 2012

목적: 본 연구는 단일 기관에서 소아암 환자의 2009 인플루엔자 A(H1N1) [A(H1N1)pdm09] 감염 양상을 조사하고 이전의 계절 인플루엔자 감염과 비교 분석하고자 하였다. 방법: 삼성서울병원에서 2009년 8월부터 2010년 2월까지 A(H1N1)pdm09 감염, 2000년 1월부터 2009년 5월까지 계절 인플루엔자 A 감염이 확진된 소아암 환자의 의무기록을 후향적으로 분석하였다. 결과: 82명의 소아암 환자에서 A(H1N1)pdm09 감염이 확진되었다. 10명(12.2%)의 환자에서 하기도 감염증 또는 호흡기 외 감염이 발생하였다. 3명(3.7%)의 환자가 사망하였고 그 중 2명은 A(H1N1)pdm09 기여 사망이었다. 합병된 감염증과 관련하여 유의성을 가지는 위험인자는 감염의 시점(2009년 44-45주)과 병원 내 감염이었다. 이전의 계절 인플루엔자 A 감염과 비교하였을 때 임상적 특성에는 유의한 차이가 없었으나 A(H1N1) pdm09 감염에서 적극적인 항바이러스제 치료가 시행되었다. 결론: 소아암 환자에서 A(H1N1)pdm 감염은 경증부터 중증까지 다양한 임상 경과를 보였으며 이전의 계절 인플루엔자와 비교했을 때 임상 양상의 유의한 차이는 없었다.

• Tribology and Lubricants
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• 제4권2호
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• pp.44-51
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• 1988

Titanium carbide(TiC), Titanium nitride(TiN), and Titanium carbonnitride(Ti(C,N)) films were deposited on $Si_3N_4$-TiC composite cutting tools by chemical vapor deposition(CVD) using $TiCl_4-CH_4-H_2$, $TiCl_4-N_2-H_2$, and $TiCl_4-CH_4-N_2-H_2$ gas mixtures, respectively. The experimental results indicate that TiC coatings compared with TiN coatings on $Si_3N_4$ -TiC ceramic have an improved microstructural property, good thermal shock resistance, and good interfacial bonding. However TiN coatings compared with TiC coatings have a low friction coefficient with steel and good chemical stability. It is found by cutting test that coated insert compared with $Si_3N_4$-TiC ceramic have a superior flank and crater wear resistance. And multilayer coating compared with monolayer coating shows a improved wear resistance.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2351-2357
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• 2011

Three new metal-organic copper(II) complexes, $[Cu(H_2PZTC)_2]_n{\cdot}2nH_2O$ (1), $[Cu(HPZTC){\cdot}2H_2O]_n{\cdot}2nH_2O$ (2), and $Cu_2[(PZHD)(OH)(H_2O)_2]_n$ (3) ($H_3PZTC$ = pyrazine-2,3,5-tricarboxylic acid, $PZHD^{3-}$ = 2-hydroxypyrazine-3,5-dicarboxylate), have been synthesized from $Cu(II)/H_3PZTC$ system under different synthetic conditions, and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and thermogravimetric analysis. In complexes 1 and 2, $H_3PZTC$ ligands loose one and two protons, which were transformed into $H_2PZTC^-$ anion and $HPZTC^{2-}$ dianion under different preparation condition, respectively. Furthermore, two ligands coordinate with Cu(II) cations in different modes, leading to the formation of the different chain structures. In complex 3, $H_3PZTC$ ligand was converted into a new ligand-PZHD by in situ decarboxylation and hydroxylation under a higher pH value than that for complexes 1 and 2. PZHD ligands link the Cu(II) cations to form a 2D layer structure. These results demonstrate that the preparation conditions, including pH value and reaction temperature etc, play an important role in the construction of complexes based on $H_3PZTC$ ligand.

• 정보처리학회논문지A
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• 제9A권3호
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• pp.333-340
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• 2002

임베딩은 어떤 상호연결망 G를 다른 상호연결망 H에 사상시키는 것으로 연결망 G에서 개발된 알고리즘을 다른 연결망 H에서 시뮬레이션 할 수 있게 한다. 본 논문에서는 먼저 Hierarchical Cubic Network HCN(n, n) and Hierarchical Folded-hypercube Network HFN(n, n) 사이의 임베딩 방법을 제시한다. HCN(n, n)과 HFN(n, n)은 하이퍼큐브에서 제안된 성질을 가지면서 하이퍼큐브의 망비용 (분지수$\times$지름)을 개선한 상호연결망이다. HCN(n, n)은 HFN(n, n)에 연장율 3, 밀집율 2로 임베딩되고 평균연장율이 2 이하임을 보인다. HFN（n, n）은 HCN（n, n）에 연장율 0(n)에 임베딩 되지만, 평균연장율이 2 이하임을 보인다. 마지막으로 HCN（n, n）의 고장허용도에 대해 논하고, HCN（n, n）이 최대 고장 허용도(maximally fault tolerant)를 가짐을 보인다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 춘계종합학술대회
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• pp.501-504
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• 2003

본 연구에서는 박막트랜지스터의 특성 향상을 위하여 강유전성 박막을 게이트 절연충으로 사용하기 위하여 강유전성 박막과 a-Si:H 의 계면특성을 조사하였다. 먼저 강유전성 박막 중에 대표적인 SrTiO$_3$를 E-BEAM 증착기로 박막을 형성시켰다. 형성된 박막은 $N_2$ 분위기에서 15$0^{\circ}C$~$600^{\circ}C$로 1시간 ANNEALING 하여 전자현미경으로 표면을 측정하였다. SrTiO$_3$의 유전상수는 50~100 정도였으며 항복전계는 1~l.5 MV/cm로 매우 우수한 유전특성을 갖고 있었다. 강유전체 박막 위에 a-SiN:H,a-Si:H(n-type a-Si:H) 등을 PECVD로 증착하여 MFNS구조를 형성하였다. 계면특성을 C-V PLOTTER로 측정한 결과 SrTiO$_3$ 박막은 SiN 과의 접합이 매우 안정되어 있었고 C-V특성은 SiN/a-Si:H 과 유사하였다. 그러나 FERROELECTRIC/a-S:H의 경우가 훨씬 CAPACITANCE값이 컸으며, 이는 강유전체 박막의 높은 유전상수에 기인 된 것이라 생각된다.

• 한국자기공명학회논문지
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• 제15권2호
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• pp.146-156
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• 2011

The line widths and spin-lattice relaxation times of protons in $[N(C_2H_5)_4]_2CoCl_4$ and $[N(CH_3)_4]_2CoCl_4$ single crystals were investigated in the temperature range 160-400 K. The temperature dependences of the spin-lattice relaxation times are attributed to the molecular motions of the ethyl and methyl groups in the $[N(C_2H_5)_4]^+$ and $[N(CH_3)_4]^+$ ions respectively. The NMR line widths indicate that the ethyl groups in $[N(C_2H_5)_4]_2CoCl_4$ have one more degree of freedom than the methyl groups in $[N(CH_3)_4]_2CoCl_4$. The experimental results are interpreted in terms of the reorientations of the methyl and ethyl groups.

• Bulletin of the Korean Chemical Society
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• 제7권6호
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• pp.468-471
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• 1986

The isolated products from the reactions of $Rh(ClO_4)(CO)(PPh_3)_2$ (1) with CH_2$ = $CHCO_2C_2H_5$ (2) and trans-$CH_3CH$ = $CHCO_2C_2H_5$ (3) contain 80∼ 90% of $[Rh(CH_2 = CHCO_2C_2H_5)(CO)(PPh_3)_2]ClO_4$ (4) and [Rh(trans-$CH_3CH = CHCO_2C_2H_5(CO)(PPh_3)_2]ClO_4$ (5), respectively where 2 and 3 seem to be coordinated through the carbonyl oxygen. It has been found that complex 1 catalyzes the isomerization of $CH_2 = CH(CH_2)_8CO_2C_2H_5$ (6) to $CH_3(CH_2)_nCH = CH(CH_2)_{7-n}CO_2C_2H_5$ (n = 0∼7) under nitrogen at 25$^{\circ}C$. The isomerization of 6 is slower than that of $CH_2 = CH(CH_2)_9CH_3$ to $CH_3(CH_2)_nCH$ = $CH(CH_2)_{8-n}CH_3$ (n = 0∼8), which is understood in terms of the interactions between the carbonyl oxygen of 6 and the catalyst. It has been also observed that complex 1 catalyzes the hydrogenation of 2, 3, 6, trans-$C_6H_5CH = CHCO_2C_2H_5$ (7), $CH_3(CH_2)_7CH = CH(CH_2)_7CO_2C_2H_5$ (8) and $CH_2 = CH(CH_2)_9CH_3$ (9), and the isomerization (double bond migration) of 6 and 9 under hydrogen at 25$^{\circ}C$. The interactions between the carbonyl oxygen of the unsaturated esters and the catalyst affect the hydrogenation in such a way that the hydrogenation of the unsaturated esters becomes slower than that of simple olefins.

• 한국환경보건학회지
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• 제27권1호
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• pp.93-99
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• 2001

This study aims at finding out pertinent reaction conditions for treating high concentration ammonia contained in N-chemical factory wastewater with decompressed ammonia stripping method that was designed. And it also tries to investigate adsorption capability of removed ammonia to soil. The results from experiments are as follows ; 1. The removal rate of N $H_3$-N of synthetic wastewater was under 85% at pH 10 with decompressed ammonia stripping method. The reaction time in pressure 360 mmHg at pH 11 and 12 was shorter than in 460 mmHg, and the removal rate of N $H_3$-N with decompressed ammonia stripping method at 9$0^{\circ}C$ was 11~15% higher than air stripping 2. The optimum conditions for decompressed ammonia stripping with synthetic sample were shown as pH 12, temperature 9$0^{\circ}C$, internal reaction pressure 460 mmHg and reaction time 50 minutes. These conditions were applied to treat the wastewater containing organic-N 290.5mg/$\ell$, N $H_3$-N 168.9mg/$\ell$, N $O_2$-N 23.2mg/$\ell$, N $O_3$-N 252.4mg/$\ell$, T-N 735mg/$\ell$. Organic-N turned out to be removed 60%, the removal rate of N $H_3$-N IS 94%, T-N is 50%. But N $O_2$-N and N $O_3$-N were increased with 7.8% and 14.9% respectively. 3. The CO $D_{Sr}$ removal rate in decompressed ammonia stripping reaction was 42% and S $O_4$$^{2-}$ was removed 8.2%. It was turned out caused with higher pH and thermolysis. 4. In soil adsorption of ammonia desorbed from the decompressed stripping process of wastewater, the recovery rate was 76% in wet soil.

• 한국의류학회지
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• 제23권3호
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• pp.353-360
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• 1999

An investigation made of the variations of angle of bias on the top of the sleeve cap curve line and calculated easing contraction ratio by capheights(A ; a,h$\times$5,/6) B: A, H/4 +4cm C:A.H/3 D: A.H/ 4+3cm E:AH/4+2cm, F: A,H/4+1cm, G: A,H/4, H:A,H/6, I:A,H/8) and the efects of easing contraction on the cap curve lines of sleeve A, D, G by easing stitch density with the gathering foot: sewing condition-lockstitch industrial machine stitch density(N1.0 ; 38stitches/3cm N1.5: 26stitches/3cm, N2.0 ; 19stitches/3cm, N2.5 ; 14stitches/ 3cm) The results obtained were as follows; 1) The variations of the angle of bias on the top of the sleeve cap curve line by cap heights can be done according to the angle balance (front; $\alpha$-$\beta$ back ; $\alpha$'- $\beta$') between the angle (front ;$\alpha$, $\beta$, back ; $\alpha$'- $\beta$') of bias of the two base-lines. 2) The higher cap height the more higher the calculated easing contraction ratio. 3) The lower the stitch density the higher easing contraction ratio. 4) The effects of easing contraction was that sleeve G was more than sleeve A, D.