• ALGAE
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• v.33 no.1
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• pp.69-84
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• 2018

We examined the species diversity of Herposiphonia on Korean coasts, based on a combination of morphology and molecular analyses of the mitochondrial COI-5P DNA barcode marker and plastid rbcL gene. We report the presence of eight species including three novel species: H. donghaensis sp. nov., H. jejuinsula sp. nov., H. sparsa sp. nov., H. caespitosa, H. fissidentoides, H. insidiosa, H. parca, and H. subdisticha. Specimens were separated into eight clades in both the COI-5P and rbcL gene analyses, with 1.3-19.6 and 6.6-15% interspecific sequence divergence, respectively. These eight species are also distinguishable by several morphological characteristics such as: branching pattern (d/i pattern in H. donghaensis sp. nov. and H. sparsa sp. nov.; d/d/d/i pattern in others), shape of determinate branch (ligulate in H. fissidentoides; terete in others), number of vegetative trichoblasts (1-2 in H. insidiosa and H. sparsa sp. nov.; 3-4 in H. caespitosa; absent in others), and number of segments and pericentral cells in determinate branches. About three novel species revealed by our analyses, H. donghaensis sp. nov. is newly discovered, and H. jejuinsula sp. nov. and H. sparsa sp. nov. were previously reported in Korea as H. nuda and H. secunda, respectively. Our results show that DNA barcoding and rbcL analyses are useful for delimiting species boundaries and discovering cryptic species diversity in the genus Herposiphonia.

• Bulletin of the Korean Mathematical Society
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• v.46 no.1
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• pp.99-105
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• 2009

Let $M=H_1{\cup}_SH_2$ be a Heegaard splitting of a 3-manifold M, D be an essential disk in $H_1$ and A be an essential annulus in $H_2$. Suppose D and A intersect in one point. First, we show that a Heegaard splitting admitting such a (D, A) pair satisfies the disjoint curve property, yet there are infinitely many examples of strongly irreducible Heegaard splittings with such (D, A) pairs. In the second half, we obtain another Heegaard splitting $M=H'_1{\cup}_{S'}H'_2$ by removing the neighborhood of A from $H_2$ and attaching it to $H_1$, and show that $M=H'_1{\cup}_{S'}H'_2$ also has a (D, A) pair with $|D{\cap}A|=1$.

• Journal of applied mathematics & informatics
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• v.40 no.5_6
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• pp.1129-1135
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• 2022

The purpose of this research is to find an extension of the renowned Chernoff theorem on standard operator algebra. Infact, we prove the following result: Let H be a real (or complex) Banach space and 𝓛(H) be the algebra of bounded linear operators on H. Let 𝓐(H) ⊂ 𝓛(H) be a standard operator algebra. Suppose that D : 𝓐(H) → 𝓛(H) is a linear mapping satisfying the relation D(AⁿBⁿ) = D(Aⁿ)Bⁿ + AⁿD(Bⁿ) for all A, B ∈ 𝓐(H). Then D is a linear derivation on 𝓐(H). In particular, D is continuous. We also present the limitations on such identity by an example.

• Journal of the Korean Chemical Society
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• v.18 no.3
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• pp.157-170
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• 1974

The effects of ionic strength on the polynucleation reaction of tungstate ions and the protonized reaction of polytungstate ions have been investigated in the range of ionic strength from 1 M to 4 M KCl.The hexatungstate ions and the protonized forms of hexatungstate ions are formed in the tungstate solutions whose ionic strengths are 1 M to 4 M KCl. The equilibrium constants for the formation of hexatungstate ions and the protonized forms of hexatungstate ions are calculated in the range of ionic strength from 1 M to 4M KCl. The enthalpy changes for the formation of hexatungstate ions and the protonized forms of hexatungstate ions are as follows; $7H^++{6WO_4}^{2-}={HW_6O_{21}}^{5-}+3H_2O\;\;{\Delta}H^{\circ}=-62.4{\pm}0.6$$H^++{HW_6O_{21}}^{5-}={H_2W_6O_{21}}^{4-}\;\;{\Delta}H+_1^{\circ}=-4.12{\pm}0.10$$H^++{H_2W_6O_{21}}^{4-}={ H_3W_6O_{21}}^{3-}\;\;{\Delta}H_2^{\circ}=-4.36{\pm}0.30$ The free energy and entropy changes for the above reactions have been also calculated. A linear relation is formed between $log k_{6,7}$ and ionic strength, and $log k_1\;or\;log k_2\;vs{\cdot}{\mu}.$ $log k_{6,7}\;=\;D{\mu}+I,\;\;where\;D\;=\;1.66{\pm}0.02$$log k_1\;=\;D_1{\mu}+I_1,\;\;where\;D_1\;=\;-8.065{\pm}0.001$$log k_2\;=\;D_2{\mu}+I_2,\;\;where\;D_2\;=\;-0.376{\pm}0.006$

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.333-333
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• 2011

We studied the H/D exchange kinetics of pure and acid dopped water-ice film by using the techniques of reactive ions scattering (RIS) and low energy sputtering (LES) with low kinetic energy cesium ion beam (<35 eV). From RIS, neutral water isotopomers were detected in the form of cesium-molecule ion clusters, $CsX^+$ (X= $H_2O$, HDO, $D_2O$). Ionic species, like $H_3O^+$, $DH_2O^+$, $D_2HO^+$, $D_3O^+$, adsorbed on the surface were ejected via LES process. Those techniques allowed us to trace the isotopomeric populations of water-ice film. To show the catalytic effect of excess proton in the H/D exchange reaction, our study was conducted with two types of water-ice films. In film 1, about 0.5 BL of $H_2O$ was adsorbed on HCl (0.1 ML) dopped $D_2O$ (8 BL) film. In film 2, similar amount of $H_2O$ used in film 1 was adsorbed on pure $D_2O$ film. Kinetic data were obtained from each film type for 90-110 K (film 1) and 110-130 K (film 2) and fitted with numerically integrated lines. Through the Arrhenius plot of kinetic coefficient deduced from fitting of the H/D exchange reaction, the activation energy of film 1 and 2 were estimated to be $10{\pm}3kJmol^{-1}$ and $17{\pm}4kJmol^{-1}$. This activation barrier difference could be understood from detailed pictures of H/D exchange. In film 2, both the formation of ion pair, $H_3O^+$ and OH. and proton transfer were needed for the H/D exchange. However, in film 1, only proton transfer was necessary but ion pair formation was not, so this might reduce the activation energy.

• Journal of Korea Foresty Energy
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• v.17 no.1
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• pp.23-29
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• 1998

This study was carried out to develop the regression model for estimating biomass of natural Pinus densiflora forests by stand density in northeast Chinese area of Mt. Paekdu. Four allometric regression models(W=aD$^b$, W=a(D$^2$H)$^b$. logW=a+b$\cdot$ logD+cD and logW=a+b$\cdot$log(D$^2$H)+c(D$^2$H)) were used to estimate biomass for each of the tree components. The suitable regression model for estimating biomass of stem, bark and whole tree above ground was logW=a+b$\cdot$log(D$^2$H)+c(D$^2$H), and that for biomass of branch, needle and needle area, logW=a+b$\cdot$logD+cD for all of the stand density classes.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.1
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• pp.52-61
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• 1997

This study was aimed to decrease AOX(Adsorbed Organic Halide Compounds) by applying bleaching methods of A(HNO$_3$ ＋ NaNO$_2$) and $D^{(H/L)}$(dual pH chlorine dioxide bleaching) to conventional OCEDED bleaching stages. And so we investigate the effects of NSA treatment and the influence of production rate of ion species in chlorine dioxide and pulp mixtures according to various pH as well as dual pH on pulp bleaching. Finally the effects of AOC_DED^{(H/L)}ED^{(H/L)}$ bleaching stage were investigated by measuring AOX, brightness, kappa number and viscosity of pulps. A stage was treated by using 4% $HNO_3$ and 0.05~2.0% $NaNO_2$ on pulp and $D^{(H/L)}$ stage was like that pulp mixed with chlorine dioxide solution was adjusted at pH 7.0 and reacted in pulp cosistency 3%, S~20min, $70^{\circ}C$, and then successively for 160~175min at pH 4.0. It was found that suitable $NaNO_2$ addition rate was at 0.6% where the brigtness of pulp was most higher and pulp viscosity was not decreased much. Chlorate ($CIO_3$) was decreased according to pH increase but chlorite($CIO_2$) was highly decreased according to pH increase. And chloride was slightly increased with pH increase. The applying of A and D^{(H/L)}$ bleaching stages to some various multiple bleaching stages ($AOC_DED^{(H/L)}/EopD^{(H/L)} etc.$) had good results that brightness was increased more 2~3% ISO than conventional method(OCEDEopD), but viscosity was dropped by only 1~2cps.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.611-612
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• 2006

• Journal of the Korean Chemical Society
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• v.41 no.12
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• pp.645-652
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• 1997

Hydride complexes Cp*Ru(CO)(PR3)H (Cp*=η5-C5Me5, PR3=PMe3, PEt3, PMePh2, PPh3, PCy3)(4a-4f) were synthesized by the reaction of the corresponding chloro complex Cp*Ru(CO)(PR3)Cl (3a-3f) with various hydridic reagent (NaBH4, LiAlH4, LiBEt3H) or NaOMe. Irradiation of Cp*Ru(CO)(PCy3)H (5e) in C6D6 solution with UV light caused H/D exchange reaction between coordinated Cp*, PCy3 and/or Ru-H ligand proton and a deuterium of the deuterated aromatic solvent through a series of inter- and intramolecular C-H activation. The proposed mechanism was described.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.870-870
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• 2006