• 대한수학회보
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• 제49권1호
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• pp.205-211
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• 2012

Let R be a graded Noetherian domain and A a graded Krull overring of R. We show that if h-dim $R\leq2$, then A is a graded Noetherian domain with h-dim $A\leq2$. This is a generalization of the well-know theorem that a Krull overring of a Noetherian domain with dimension $\leq2$ is also a Noetherian domain with dimension $\leq2$.

• East Asian mathematical journal
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• 제38권5호
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• pp.583-591
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• 2022

Let K be an imaginary quadratic field and 𝒪 be an order in K. Let H_𝒪 be the ring class field of 𝒪. Furthermore, for a positive integer N, let K_𝒪,N be the ray class field modulo N𝒪 of 𝒪. When the discriminant of 𝒪 is different from -3 and -4, we construct an extended form class group which is isomorphic to the Galois group Gal(K_𝒪,N/H_𝒪) and describe its Galois action on K_𝒪,N in a concrete way.

• 한국자기공명학회논문지
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• 제6권2호
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• pp.118-131
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• 2002

Manganese-doped H-SAPO-34 samples were prepared by an ion-exchanged reaction between H-SAPO-34 and paramagnetic Mn(II) species in methanol media and characterized by ESR and Electron Spin-Echo Modulation(ESEM) studies. In the hydrated (W)MnH-SAPO-34 measured in water, the Mn(II) ion was octahedrally coordinated with four framework oxygens and two water molecules at a displaced site IV of the eight membered ring window in the ellipsoidal cavity, while the Mn(II) ion was octahedrally coordinated to three framework oxygens and three water molecules at a displaced site I' of the six membered ring window in the ellipsoidal cavity in hydrated(M)MnH-SAPO-34 measured in methanol. The similar result was found in the experiments with methanol adsorbents except ethanol.

• Bulletin of the Korean Chemical Society
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• 제7권5호
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• pp.412-412
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• 1986

• Journal of applied mathematics & informatics
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• 제17권1_2_3호
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• pp.771-778
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• 2005

In this paper we shall give some group properties derived from the characteristic ring-module $_X(M)$, using the fact that $_X(M)_H$ is a conjugate to $_X(M)_{Ha}$ when M is an invertible right R-module. Also we shall prove that_X(M)$ is group-isomorphic to TR and some normal subgroup properties if M is invertible and R is commutative.

• 호남수학학술지
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• 제23권1호
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• pp.1-4
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• 2001

In [2, 7.3.2], the set of attached prime ideals of local cohomology module $H_m^n(M)$ were calculated, where (A, m) be Noetherian local ring, M finite A-module and $dim_A(M)=n$, and also in the special case in which furthermore A is a homomorphic image of a Gornestien local ring (A', m') (see [2, 11.3.6]). In this paper, we shall obtain this set, by another way in this special case.

• Bulletin of the Korean Chemical Society
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• 제23권11호
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• pp.1629-1634
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• 2002

Reaction of tetrahomodioxa p-phenylcalix[4]arene with alkyl halide and NaH in DMF leads to the title tetra-alkylated derivatives, 7,13,21,27-tetra-phenyl-29,30,31,32-tetraalkyloxy-2,3,16,17-tetrahomo-3,17-dioxacalix [4]arenes, their preferred conformations were determined by NMR spectra as C-1,2-alternate. The molecular structure of allyl derivative has been solved by X-ray diffraction methods. The molecules have a conformation with pseudo center of symmetry. The benzene ring A is up, ring C is down, B and D rings are flat with respect to the plane of the macrocyclic ring.

• 약학회지
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• 제8권2호
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• pp.59-61
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• 1964

A new alkaloid, named tenuidine was isolated from Polygala tenuifolia Willdenow. Its molecular formula corresponded to $C_{21}$ $H_{31}$ $O_{5}$ $N_{3}$ and its constants were m.p.256, [.alpha.]$_{D}$$^{18.5}$=1200.deg.(ethanol). Its infrared absorption spectra exhibited bands at 3.300, 1600, 1580, 1500 $cm^{-1}$ / confirming indole ring and at 2800-2700 $cm^{-1}$ / indicating quinoline ring. Bands at 1610, 1530 $cm^{-1}$ / indicated the presences of benzene ring and 1642$cm^{-1}$ / carbochelate.e.e.

• Bulletin of the Korean Chemical Society
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• 제20권12호
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• pp.1433-1436
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• 1999

The 2-(2,4-dimethoxyphenyl)-4-MDO (2) underwent polymerization with ring opening as well as cyclization reaction in the presence of various cationic catalysts such as boron trifluoride, trifluoromethanesulfonic acid, p-toluenesulfonic acid, hydrochloric acid and trifluoroacetic acid. They afforded a mixture of the ring-opened poly(keto ether) and 3(2H)-dihydrofuranone derivative. Both the methylene group and oxygen atom of 1,3-dioxolane ring were participated in the reaction with cationic catalyst. The contents of the polymer and cyclization product were variable according to the acid strength of the cationic catalysts.

• 한국광학회지
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• 제14권6호
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• pp.674-679
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• 2003

본 연구에서는 C-밴드와 L-밴드 파장(1525 nm-1625 nm)에서 파장 변화가 가능한 광섬유 링 레이저를 제작하고, 이를 이용하여 아세틸렌 분자 전이선에 대한 분광연구를 수행하였다. 제작된 광섬유 링 레이저는 공진기 내부에 FFP-TF(Fiber Fabry-Perot Tunable Filter)를 이용하여 약 102 nm(1510.4-1612.6 nm)의 범위에서 파장을 연속 가변할 수 있었다. 광섬유 링 레이저의 파장가변특성을 이용하여 C-밴드(1525-1565 nm)에서 흡수선이 많은 아세틸렌($^{13}$C$_2$H$_2$)분자에서 50개 이상의 전이선에 대하여 높은 신호대 잡음비를 갖는 흡수 스펙트럼을 측정하였다.