• 제목/요약/키워드: V-ring

검색결과 566건 처리시간 0.032초

$^{13}C$ NMR Studies of the Chelate Ring Opening-Closing Process in (Nitrilotriacetato)vanadate(V) dioxovandate(V) Ion

  • Lee, Man-Ho;Schaumburg, Kjeld
    • Bulletin of the Korean Chemical Society
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    • 제11권5호
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    • pp.399-402
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    • 1990
  • Activation parameters of the exchange between two types of glycinate groups in (nitrilotriacetato)dioxovanadate(V) ion, $[VO_2(NTA)]^{2-}$, have been determined as the results of $^{13}C$ NMR measurements over a range of temperatures between 277 and 306$^{\circ}K$. The exchange mechanism is proposed on the basis of the chelate ring opening-closing process, assuming rupture of the metal-oxygen (glycinate) bond trans to V = O bond to give a five-coordinated intermediate.

Guard Ring을 가진 Trench 쇼트키 다이오드 (Trench Schottky Diode with Gurad Ring)

  • 문진우;정상구;최연익
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.26-28
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    • 2001
  • A Trench schottky diode with guard ring is proposed to improve the forward current density and reverse breakdown voltage. The simulation results by Silvaco have shown that the reverse breakdown voltage of the proposed device was found to be 22.1V while that of conventional trench device was 17.25V. The breakdown voltage of the proposed structure was 28.1% higher than that of the conventional trench structure.

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CHOW GROUPS OF COMPLETE REGULAR LOCAL RINGS III

  • Lee, Si-Chang
    • 대한수학회논문집
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    • 제17권2호
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    • pp.221-227
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    • 2002
  • In this paper we will show that the followings ; (1) Let R be a regular local ring of dimension n. Then $A_{n-2}$(R) = 0. (2) Let R be a regular local ring of dimension n and I be an ideal in R of height 3 such that R/I is a Gorenstein ring. Then [I] = 0 in $A_{n-3}$(R). (3) Let R = V[[ $X_1$, $X_2$, …, $X_{5}$ ]]/(p+ $X_1$$^{t1}$ + $X_2$$^{t2}$ + $X_3$$^{t3}$ + $X_4$$^2$+ $X_{5}$ $^2$/), where p $\neq$2, $t_1$, $t_2$, $t_3$ are arbitrary positive integers and V is a complete discrete valuation ring with (p) = mv. Assume that R/m is algebraically closed. Then all the Chow group for R is 0 except the last Chow group.group.oup.

Nonlinear spectral design analysis of a structure for hybrid self-centring device enabled structures

  • Golzar, Farzin G.;Rodgers, Geoffrey W.;Chase, J. Geoffrey
    • Structural Engineering and Mechanics
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    • 제61권6호
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    • pp.701-709
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    • 2017
  • Seismic dissipation devices can play a crucial role in mitigating earthquake damages, loss of life and post-event repair and downtime costs. This research investigates the use of ring springs with high-force-to-volume (HF2V) dissipaters to create damage-free, recentring connections and structures. HF2V devices are passive rate-dependent extrusion-based devices with high energy absorption characteristics. Ring springs are passive energy dissipation devices with high self-centring capability to reduce the residual displacements. Dynamic behaviour of a system with nonlinear structural stiffness and supplemental hybrid damping via HF2V devices and ring spring dampers is used to investigate the design space and potential. HF2V devices are modelled with design forces equal to 5% and 10% of seismic weight and ring springs are modelled with loading stiffness values of 20% and 40% of initial structural stiffness and respective unloading stiffness of 7% and 14% of structural stiffness (equivalent to 35% of their loading stiffness). Using a suite of 20 design level earthquake ground motions, nonlinear response spectra for 8 different configurations are generated. Results show up to 50% reduction in peak displacements and greater than 80% reduction in residual displacements of augmented structure compared to the baseline structure. These gains come at a cost of a significant rise in the base shear values up to 200% mainly as a result of the force contributed by the supplemental devices.

Specific Association of Riboflavin and Penicillin Derivatives in Chloroform Solution

  • Yu, Byung-Sul
    • 약학회지
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    • 제18권3호
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    • pp.209-216
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    • 1974
  • From the measurements of infrared and fluorescence spectra riboflavin-2',3',4',5'-tetraacetate has been found to associate with penicillin-V more than strongly with themselves. They form the 1 : 1 cyclic hydrogen bonded dimer through the imino and the 2-C carbonyl groups of the isoalloxazine ring and the imino group of the penicillin-V ressidue. Pernicillin-V is an effective quencher of the fluorescence of riboflavin through hydrogen bonds partly due to the collision interaction with the penicillin ring.

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ON GENERALIZED GRADED CROSSED PRODUCTS AND KUMMER SUBFIELDS OF SIMPLE ALGEBRAS

  • Bennis, Driss;Mounirh, Karim;Taraza, Fouad
    • 대한수학회보
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    • 제56권4호
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    • pp.939-959
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    • 2019
  • Using generalized graded crossed products, we give necessary and sufficient conditions for a simple algebra over a Henselian valued field (under some hypotheses) to have Kummer subfields. This study generalizes some known works. We also study many properties of generalized graded crossed products and conditions for embedding a graded simple algebra into a matrix algebra of a graded division ring.

Some Extensions of Rings with Noetherian Spectrum

  • Park, Min Ji;Lim, Jung Wook
    • Kyungpook Mathematical Journal
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    • 제61권3호
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    • pp.487-494
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    • 2021
  • In this paper, we study rings with Noetherian spectrum, rings with locally Noetherian spectrum and rings with t-locally Noetherian spectrum in terms of the polynomial ring, the Serre's conjecture ring, the Nagata ring and the t-Nagata ring. In fact, we show that a commutative ring R with identity has Noetherian spectrum if and only if the Serre's conjecture ring R[X]U has Noetherian spectrum, if and only if the Nagata ring R[X]N has Noetherian spectrum. We also prove that an integral domain D has locally Noetherian spectrum if and only if the Nagata ring D[X]N has locally Noetherian spectrum. Finally, we show that an integral domain D has t-locally Noetherian spectrum if and only if the polynomial ring D[X] has t-locally Noetherian spectrum, if and only if the t-Nagata ring $D[X]_{N_v}$ has (t-)locally Noetherian spectrum.