• Bulletin of the Korean Chemical Society
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• 제20권3호
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• pp.297-300
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• 1999

The protonation constants of the macrocyclic ligands, 1,4-dioxa-7,10,13,16-tetraaza-cyclooctadecane-N,N',N",N"'-tetra(acetic acid) [N-ac4[18]aneN402] and 1,4-dioxa-7,10,13,16-tetraazacyclooctadecane-1,4-dioxa-7,10,13,16-N,N',N",N"'-tetra(methylacetic acid) [N-meac4[18]aneN4O2] have been determined by using potentiometric method. The protonation constants of the N-ac4[18]aneN4O2 were 9.31 for logK1H, 8.94 for logK2H, 7.82 for logK3H, 4.48 for logK4H and 2.94 for logK5H. And the protonation constants of the N-meac4[18]aneN4O2 were 9.34 for logK1H, 9.13 for logK2H, 8.05 for logK3H, 5.86 for logK4H, and 3.55 for logK5H. The stability constants of complexes on the divalent transition ions (Co2+, Ni2+, Cu2+, and Zn2+) and tiivalent metal ions (Ce3+, Eu3+, Gd3+, and Yb3+) with ligands N-ac4[18]-aneN4O2 and N-meac4[18]aneN4O2 have been obtained from the potentiometric data with the aid of the BEST program. The three higher values of the protonation constants for synthesized macrocyclic ligands correspond to the protonation of nitrogen atoms, and the fourth and fifth values correspond to the protonation of the carboxylate groups for the N-ac4[18]aneN4O2 and N-meac4[18]aneN4O2. The meatal ion affinities of the two tetra-azamacrocyclic ligands with four pendant acetate donor groups or methylacetate donor groups are compared. The effects of the metal ions on the stabilities are discussed, and the trends in stability constants resulting from changing the macrocyclic ring with pendant donor groups and acidity of the metal ions.

• 산업융합연구
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• 제19권4호
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• pp.23-28
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• 2021

본 논문은 미해결 문제로 알려진 36 장교문제(n = 6)와 관련된 오일러 방진 퍼즐 게임 문제에 대해 n = [3, ∞]의 문제를 풀 수 있는 일정한 패턴 규칙을 찾고자 시도하였다. 이 문제의 해는 현재까지 [3, 10]에 대해 n = 6만 존재하지 않고 나머지 모든 숫자에 대한 해는 존재하는 것으로 알려져 있다. 또한, 기존 연구는 특정 숫자 n에 대해 컴퓨터 프로그램으로 랜덤한 배정 결과를 찾고자 하여 n = [11, ∞]에 대해서는 해를 찾기가 쉽지 않아 미해결 과제로 남아있다. 기존 연구는 n = [3, 10]으로 한정시킨 반면에, 본 논문은 n = [3, ∞]영역에서 어떠한 n의 값에 대해서도 해를 찾을 수 있는 일반화된 패턴을 찾고자 시도하였다. 본 논문에서는 n = odd, 4k even, 4k+2 even의 세 부분으로 분할하여 n = odd와 4k even(n/2 = even)에 대한 간단하면서도 일정한 패턴을 찾는데 성공하였다. 그러나 4k+2 even(n/2 = odd)에 대해서는 패턴을 찾지 못하였다.

• Toxicological Research
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• 제14권2호
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• pp.177-181
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• 1998

Dithiocarbamate and mixed disulfide containing allyl functions were designed and synthesized as putative chemopreventive agents, i.e. N,N-diallyldithiocarbamate (DATC) and S-(N,N-diallyldithiocarbamoyl)-N-acetylcysteine (AC-DATC). DATC and AC-DATC were administered and the activities of cytosolic glutathione S-transferase (GST), glutathione reductase (GR) and microsomal N-nitrosodiethylamine (NDEA) deethylase were assayed in order to test the effects of these organosulfur com-pounds on the detoxification and metabolic activation system of NDEA. The amounts of hepatic glutathione (GSH and GSSG) was also determined. The administration of DATC to rats led to an increase in the activity of GR and to an inhibition of CYP2E1-mediated NDEA deethylation. AC-DATC induced the activity of GR and GST, increased the hepatic GSH content and inhibited the rate of NDEA deethylation. The level of GSSG was decreased as a consequence of the increased activity of GR. These effects may contribute to possible antimutagenic and anticarcinogenic action of the dithiocarbamates investigated.

• 호남수학학술지
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• 제34권4호
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• pp.519-531
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• 2012

Let ${\sigma}_s(N)={\sum}_{d{\mid}N}d^s$. Next, the convolution sums ${\sum}_{k<N/3}{\sigma}_1(3^mk){\sigma}_1(2^n(N-3k))$, ${\sum}_{<N/3}{\sigma}_1(2^mk){\sigma}_1(3^n(N-3k))$, etc., are evaluated for all $N{\in}\mathbb{N}$ with $m$, $n{\in}\mathbb{N}{\cup}\{0\}$.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2004년도 추계학술대회 학술발표 논문집 제14권 제2호
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• pp.345-350
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• 2004

In this paper we study the controllability for the nonlinear fuzzy integro-differential equations on E$_{N}$$^{n}$ by using the concept of fuzzy number of dimension n whose values are normal, convex, upper semicontinuous and compactly supported surface in R$^n$. E$_{N}$$^{n}$ be the set of all fuzzy numbers in R$^n$ with edges having bases parallel to axis X$_1$, X$_2$, …, X$_{n}$ .X> .

• Archives of Pharmacal Research
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• 제9권1호
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• pp.15-18
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• 1986

Various naturally occuring methylated amino acid derivatives were resolved on high performance liquid chromatography (HPLC), using o-phthadialdehyde as a fluorogenic reagent. We separated .$\varepsilon$-N-monomethyllysine, $\varepsilon$-N- dimethyllysine, and $\varepsilon$-N-acetyllysine from lysine derivatives. $N^{G}$-Monomethylarginine and $N^{G}$-dimethylarginine were separated from arginine derivatives. However, $\varepsilon$-N-monomethyllsine and $\varepsilon$-N-trimethyllysine, $N^{G}$, $N^{G}$-dimethylarginine and $N^{G}$, $N^{G}$-dimethylarginine were not resolved under the conditions employed. S-Methylmethionine, S-methylcysteine, and 1-N-methylhistidine or 3-N-methylhistidine were clearly separated from their reference amino acids, even though 1-N-methyl-and 3-N-methylhistidine coul not be separated.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 반도체 재료 센서 박막재료 전자세라믹스
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• pp.97-100
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• 2004

We have grown GaN layers with in-situ SiN mask by metal organic chemical vapor deposition (MOCVD) and study the characteristic of the GaN layer. We have changed the deposition time of SiN mask from 45s to 5min and obtain th optimum condition in 45s. The PL intensity of GaN with SiN mask improved 2 times to that without SiN mask and the carrier concentraion increased from $3.5{\times}10^{16}cm^{-3}$ to $1.8{\times}10^{17}cm^{-3}$. We have thus shown that the SiN mask improved significantly the optical properties of the GaN layer.

• Journal of applied mathematics & informatics
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• 제28권3_4호
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• pp.1025-1034
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• 2010

Let {$X_n$, $n\;{\in}\;\mathbb{Z}_+^d$} be a field of identically distributed and negatively associated random variables with mean zero and set $S_n\;=\;{\sum}_{k{\leq}n}\;X_k$, $n\;{\in}\;\mathbb{Z}_+^d$, $d\;{\geq}\;2$. We investigate precise asymptotics for ${\sum}_n|n|^{r/p-2}P(|S_n|\;{\geq}\;{\epsilon}|n|^{1/p}$ and ${\sum}_n\;\frac{(\log\;|n|)^{\delta}}{|n|}P(|S_n|\;{\geq}\;{\epsilon}\;\sqrt{|n|\log|n|)}$, ($0\;{\leq}\;{\delta}\;{\leq}\;1$) as ${\epsilon}{\searrow}0$.

• 한국전기전자재료학회논문지
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• 제14권12호
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• pp.972-978
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• 2001

Some effects of Al/N ratio on microstructure of AlN films grown on Si(111) substrates by PAMBE were investigated. Al/N ratio was controlled by rf power of N$_2$ plasma source system. Al excess or N excess conditions were obtained below or above 350 W rf power, respectively. Surface roughness and morphology of AlN film grown at Al/N=1.0 showed the best result. Under Al excess condition, it was suggested that excess Al atoms which did not contribute to the growth of AlN film prevent the normal crystal growth and make abnormal growth of some columns. However, under N excess condition, it was explained that some of the excess active N source turned into gas state and then desorbed out from substrate.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.75-78
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• 1996

The deposition condition Gf TiN films as electrode was studied by sheet resistance, TiN depositon Thickness X-ray diffraction. TiN was made by reactively DC magnetron sputtering with varying $N_2$/Ar mixture gas and substrate temperature. After finding The deposition condition of TiN films, The samples with the structure of Cu/Ta$_2$O$_{5}$, TiN/Ta$_2$O$_{5}$Si, Cu/TiN/Ta$_2$O$_{5}$ Si were prepared and were measured I-V, C-V. As a results, it was found that when TiN was deposited in an $N_2$a results, it was found that when TiN was deposited in an $N_2$atmosphere its Sheet resistance is lower n than n V$_2$Ar mixtureixture