• Title/Summary/Keyword: zeta function

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NOTE ON STIRLING POLYNOMIALS

  • Choi, Junesang
    • Journal of the Chungcheong Mathematical Society
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    • v.26 no.3
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    • pp.591-599
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    • 2013
  • A large number of sequences of polynomials and numbers have arisen in mathematics. Some of them, for example, Bernoulli polynomials and numbers, have been investigated deeply and widely. Here we aim at presenting certain interesting and (potentially) useful identities involving mainly in the second-order Eulerian numbers and Stirling polynomials, which seem to have not been given so much attention.

SOME RADIUS RESULTS OF ANALYTIC FUNCTIONS ASSOCIATED WITH THE SRIVASTAVA-ATTIYA OPERATOR

  • Kim, Yong Chan;Choi, Jae Ho
    • Nonlinear Functional Analysis and Applications
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    • v.26 no.2
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    • pp.323-329
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    • 2021
  • The main object of the present paper is to investigate some radius results of the functions f(z) = z + Σn=2 anzn(|z| < 1) with |an| ≤ n for all n ∈ ℕ. Some applications for certain operator defined through convolution are also considered.

Measurement of Isoelectric Point of Amine Oxide Zwitterionic Surfactant by QCM (Quartz Crystal Microbalance) (QCM (Quartz Crystal Microbalance)을 활용한 Amine Oxide 양쪽성 계면활성제의 등전점 측정에 관한 연구)

  • Kim, JiSung;Park, JunSeok;Lim, JongChoo
    • Applied Chemistry for Engineering
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    • v.20 no.1
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    • pp.9-14
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    • 2009
  • A zwitterionic surfactant shows not only detergency but also softening effect since it shows characteristics of a nonionic or an anionic surfactant above an isoelectric point, while showing characteristics of a cationic surfactant below an isoelectric point. Therefore, a zwitterionic surfactant can serve as a dual function surfactant by a single molecule through the interconversion of cleaning and softening effects depending on pH of the aqueous solution. In this study, the dual function characteristics of an amine oxide zwitterionic surfactant were investigated by measuring the zeta potential and the isoelectric point using quartz crystal microbalance (QCM). In addition, the physical properties of an amine oxide surfactant such as critical micelle concentration, surface tension, interfacial tension, contact angle and viscosity were measured and phase behavior study was also performed. The isoelectric point of an amine oxide surfactant determined by zeta potential measurement was near 7.35 and that obtained by QCM experiment was about 7.4, where both results were found to be close to the value reported in the literature.

Biflorin Ameliorates Memory Impairments Induced by Cholinergic Blockade in Mice

  • Jeon, Se Jin;Kim, Boseong;Ryu, Byeol;Kim, Eunji;Lee, Sunhee;Jang, Dae Sik;Ryu, Jong Hoon
    • Biomolecules & Therapeutics
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    • v.25 no.3
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    • pp.249-258
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    • 2017
  • To examine the effect of biflorin, a component of Syzygium aromaticum, on memory deficit, we introduced a scopolamine-induced cognitive deficit mouse model. A single administration of biflorin increased latency time in the passive avoidance task, ameliorated alternation behavior in the Y-maze, and increased exploration time in the Morris water maze task, indicating the improvement of cognitive behaviors against cholinergic dysfunction. The biflorin-induced reverse of latency in the scopolamine-treated group was attenuated by MK-801, an NMDA receptor antagonist. Biflorin also enhanced cognitive function in a naïve mouse model. To understand the mechanism of biflorin for memory amelioration, we performed Western blot. Biflorin increased the activation of protein kinase C-${\zeta}$ and its downstream signaling molecules in the hippocampus. These results suggest that biflorin ameliorates drug-induced memory impairment by modulation of protein kinase C-${\zeta}$ signaling in mice, implying that biflorin could function as a possible therapeutic agent for the treatment of cognitive problems.

Variation of the Electrokinetic Potential and Surface Energy Profile of a Binary Mixture Dispersion with Mixing Ratio (이종혼합부유물질의 양에 따른 electrokinetic potential 및 surface energy profile의 변화 양상)

  • Kim, Hee-Jin;Jeong, Hye-Won;Kim, Dong-Su
    • Journal of Korean Society on Water Environment
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    • v.28 no.1
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    • pp.115-120
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    • 2012
  • Different colloidal particles generally co-exist in the water and wastewater. Thus, there needs to identify practical electrokinetic characteristics of the particles, comparing with the case when each colloidal material is independently distributed. In this study, changes of overall zeta potential was examined through mixed dispersions of $TiO_{2}$ and $MnO_{2}$. The mixing ratios were classified into 3-type in order to distinguish the effects of the proportions of each particle from those of total concentration in colloidal suspensions. The types are single colloidal dispersions of $TiO_{2}$ and $MnO_{2}$ (1:0, 0:1), mixed dispersions at different ratios (0.75:0.25, 0.5:0.5, 0.25:0.75), and a mixed dispersion with doubled concentration (1:1), respectively. It showed that the overall variation of zeta potential as a function of pH was intensified in a colloidal dispersion with the ratio of 1:1. It was concerned that the double action of ion would contribute to this result. On the one hand, the zeta potentials of each colloidal dispersion commonly decreased at the state of strong acid and base under the influence of compression of the electric double layer. The changing patterns were also considered through calculating total interaction energy between colloidal particles based on DLVO theory and measuring turbidity of the colloidal dispersions.