• Journal of the Korean Chemical Society
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• v.18 no.1
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• pp.40-46
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• 1974

The fission neutron reactions of $^{47}Ti(n.p)^{47}Sc$ and $^{93}Nb(n,{\alpha})^{90m}Y$, along with epicadmium neutron reaction of $^{96}Zr(n,{\gamma})^{97}Zr$ were used for the simultaneous determination of Ti, Nb and Zr in synthetic mixture. Prior to neutron irradiation, Ti, Zr and Nb in the mixture were separated together in one group through the cation exchange column of Dowex $50{\times}8$ resin using 0.5 M ${\alpha}$-hydroxy-iso-butyric acid as the eluent. After irradiation of the eluate the product nuclides, $^{97}Zr$, ^{47}Sc$ and ^{90m}Y$, were eluted sequentially through the same column with 0.5 M ${\alpha}$-HIBA, 0.5 M ${\alpha}$-HIBA-1 N HNO_3 and 0.5 M ${\alpha}$-HIBA-2 N HNO_3$ solution, respectively. The gamma-ray spectrometry was used for the measurement of the gamma-ray activities of the eluted nuclides. The detection limits of Nb, Ti and Zr were found to be 0.2 %, 0.01 % and 0.002 %, respectively.

• Nuclear Engineering and Technology
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• v.15 no.2
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• pp.142-148
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• 1983

Distribution coefficients between cation exchange resin (Dowex 50W$\times$8) and $\alpha$-hydroxyisobutric acid ($\alpha$-HIBA) are measured in order to separate traces of Sm, Eu, Gd and Dy from nuclear material. Individual separations are performed by pH gradient technique with 0.40M $\alpha$-HIBA from 3.40 to 3.60 in cation exchange resin after a group separation. Each of separated elements is determined with a fluorometric method except Gd by colorimetry. The results are applied to analyze Sm, Eu, Gd and Dy in magnesium diuranate (yellow cake).

• The Journal of the Petrological Society of Korea
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• v.21 no.4
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• pp.431-439
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• 2012

A column chemistry is the most useful tools for isolating the elements of interest in isotope geochemistry. Here we introduce the chemical experimental procedure for Sm, Nd, La and Ce separation such as Teflon powder or Ln-resin method using HDEHP of KIGAM, KBSI, KOPRI and ${\alpha}$-HIBA(${\alpha}$-Hydroxy Isobutyric acid) method of Nagoya University, Japan. This technical report will provide an useful information in selecting the experiment method for rare earth element isotope system study such as Sm-Nd and La-Ce isotope system.

• Journal of the Korean Chemical Society
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• v.38 no.7
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• pp.502-508
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• 1994

The measurement of trace amounts of uranium(VI) and thorium(VI) in the solutions containing high concentration of dissolved salts was carried out. The procedure using reversed phase liquid chromatography with trace enrichment techniques has been developed to cope with the high salt content of the samples. 2 ml of sample were passed through a small C_{18}$ reversed phase enrichment column with ${\alpha}$-HIBA eluent (0.11 M, pH 5.5) where the uranium and thorium were separated from other constituents and concentrated. The uranium and thorium were then backflushed from the column onto a deactivated C_{18}$ reversed phase analytical column where furthe separation was achieved with a mixed eluent (pH3.0, 0.17M ${\alpha}$-HIBA/0.0038 M 1-pentanesulfonate). The separated species were determined spectrophotometrically by postcolumn reaction with Arsenazo III, the chromogenic reagent. Detection limits were found within 1 ppb range for both species.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.213-216
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• 1996

Optically active carboxylic acid, D-(-)-$\beta$-hydroxyisobutyric acid {(D)-(-)-HIBA} is a useful chiral starting material for the preparation of enantiomerically pure bioactive compounds which have a chiral methyl carbon center in the molecule such as captopril, $\alpha$-tocopherol, erythromycin A, muscone and so on. (S)-3-Acetoxy-2-methylpropanol can be used as the precursor of (D)-(-)-HIBA, that is, chemical oxidation of the hydroxyl group and subsequent hydrolysis of acyl group in (S)-3-acetoxy-2-methylpropanol affords D-(-)-$\beta$-hydroxyisobutyric acid. (S)-3-Acetoxy-2-methyl-propanol was prepared by lipase-catalyzed asymmetric hydrolysis. In the enzymatic hydrolysis system, lipase AY (Candida rugosa) provided the expected (S)-3-acetoxy-2-methylpropanol in 60% e.e. of the enantiomeric purity under the phosphate buffer and organic co-solvent system.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.51-55
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• 2000

The woodceramics which are new porous carbon materials were obtained by carbonizing from thinned small log of Aomori HIBA (Thujopsis dolabrata S. et. Z. var. hondae M.) impregnated with phenol resin in a vacuum furnace. During the carbonization process, the resin changes into glassy carbon, which has superior property. The resin impregnation rate and bending strength depend on the types of board and density. In this paper, the manufacturing method of woodceramics made from thinned small logs of Aomori HIBA was introduced and some properties were examined.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.56-60
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• 2000

A new porous carbon material "woodceramics" was developed by carbonizing wood or woody materials impregnated with thermosetting resin. Steamed board and non-steamed board were made from thinned small log of Aomori Hiba (Thujopsis dolabrata S. et. Z. var. hondae M.). They were impregnated with phenol resin and sintered in a vacuum furnace at $650^{\circ}C$. In this paper, the manufacturing method of woodceramics and changes of dimension, weight and compressive strength were investigated. The changes of dimension, weight and compressive strength depend on the types of board and density.

• Communications of the Korean Mathematical Society
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• v.33 no.2
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• pp.651-669
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• 2018

The article is themed to classify new (fully) degenerate Hermite-Bernoulli polynomials with formulation in terms of p-adic fermionic integrals on $\mathbb{Z}_p$. The entire paper is designed to illustrate new properties in association with Daehee polynomials in a consolidated and generalized form.

• Bulletin of the Korean Mathematical Society
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• v.49 no.5
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• pp.939-947
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• 2012

In this paper, we give a generalization of the embeddings of Riemannian manifolds via their heat kernel and via a finite number of eigenfunctions. More precisely, we embed a family of Riemannian manifolds endowed with a time-dependent metric analytic in time into a Hilbert space via a finite number of eigenfunctions of the corresponding Laplacian. If furthermore the volume form on the manifold is constant with time, then we can construct an embedding with a complete eigenfunctions basis.

• Communications of the Korean Mathematical Society
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• v.26 no.2
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• pp.163-168
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• 2011

In this paper we introduce the notion of the center ZBin(X) in the semigroup Bin(X) of all binary systems on a set X, and show that if (X,${\bullet}$) ${\in}$ ZBin(X), then x ${\neq}$ y implies {x,y}=${x{\bullet}y,y{\bullet}x}$. Moreover, we show that a groupoid (X,${\bullet}$) ${\in}$ ZBin(X) if and only if it is a locally-zero groupoid.