• Journal of the Korean Chemical Society
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• 제11권4호
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• pp.165-169
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• 1967

Eine neue Methode zur Herstellung von Meßpraparation wird die Bestimmng der Spurenelemente Quecksilber, Kupfer, Blei, Zink, Nickel, Kobalt und Eisen durch Rontgenflureszenzspektrometrie entwickelt. Die Spurenelemente werden aus waßrigen Losungen durch Einleitung von Schwefelwasserstoff mit Aluminiumsulfat als Trager bei pH8 ausgefallt. Die Niederschlage der Metallsulfide werden uber Membranfilter filtriert, mit Gelatine fixiert und ihre Absolutmengen durch Rontgenfluoreszenz analyse bestimmt. Bei der geringen Dicke der auszumessenden Schichten treten Matrixeffekte nicht auf. Durch den Zusatz von Aluminiumsulfat-Trager wird eine gute Reproduzierbarkeit erzielt: Quecksilber, Kupfer, Blei, Zink, Nickel und Kobalt werden bei einer Konzentration von 50 bis 1000 p.p.b. mit einer relativen Standard-abweichung von 5.0% und Eisen bei einer Konzentration von 50∼1000 p.p.d. mit einer relativen Standardabweichung von 6.1% gemessen.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 2000년도 영호남학술대회 논문집
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• pp.196-199
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• 2000

Since the reports of CMR(colossal magnetoresistance) effects in some single crystal R-P phase $La_{1+x}Sr_{2-x}Mn_2O_7$, considerable researches have been carried out to find optimum composition and to understand the role of dimensionality in the CMR mechanism of this system. In this study, layered perovskite $Ln_xCa_{1-x}MnO_{4}$ (x=0.5, Ln=Pr, Nd, Sm, Gd) phases were synthesized by solid state reaction and their structures were refined by Rietveld method. Electrical and magnetic properties were measured between room temperature and liquid helium temperature and compared with those of two dimensional $La_{1.4}Sr_{1.6}Mn_2O_7$ phase.

• Korean Journal of Applied Biomechanics
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• 제12권2호
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• pp.381-392
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• 2002

This study attempted to indentify changeability of the factorial structure of kinematic analysis in bowling. Subjects of group composed of three groups : Higher bowers who are national representative bowers with 200 average point and one pro-bowler. Middle bowlers who are three common persons with 170 average points. Lower bowler who are three common persons with 150 average points. Motion analysis on throw motion in three groups respectively has been made through three-dimension cinematography using DLT method. Two high-speed video camera at operating 180 and 60 frame per secondary. T-test factorial structure analysis has been used to define variable relations. It was concluded that : 1. The difference of x1, x2, x4, x8, x9, x11, x12, x13 where significant between two group. 2. The difference of number of spin and angle of the back-hand where statistically significant between two group(p<.001, p<.05) 3. The correlation over r=.5 between the kinematic data x1, x2, x3, x9, x10, x11. In the rotation loading matrix Factor 1 was x1, x2, x9, x10 and Factor 2 relates to x3, x11. 4. In order to obtain the factor score as follow as ; Factor 1 = (0.248)X1 + (0.265)X2 + (-0.074)X3 + (0.259)X9 + (0.259)X10 + (-0.025)X11 Factor 2=(-0.016)X1 + (-0.055)X2 + (0.84)X3 + (-0.013)X9 + (-0.007)X10 + (0.553)X11.

• Journal of Genetic Medicine
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• 제5권2호
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• pp.139-144
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• 2008

We report on two cases of pericentric inversion of X chromosome. The cases were found in a 40-year-old man with azoospermia and in a family of a 38-year-old pregnant woman. The first case with 46,Y,inv(X)(p22.1q27) had concentrations of LH, prolactin, estradiol, and testosterone that were within normal ranges; however, FSH levels were elevated. Testis biopsy revealed maturation arrest at the primary and secondary spermatocytes without spermatozoa. There were no microdeletions in the 6 loci of chromosome Y. For the second case, the cytogenetic study of thepregnant woman referring for advanced maternal age and a family history of inversion X chromosome was 46,X,inv(X)(p22.11q27.2). The karyotype of her fetus was 46,X,inv(X)(p22.1q27). Among other family members, the karyotypes of an older sister in pregnancy and her fetus were 46,X,inv(X)(p22.11q27.2), and 46,Y,?inv(X), respectively. The proband's father was 46,Y,inv(X)(p22.11q27.2). All carriers in the family discussed above were fertile and phenotypically normal. In addition, the ratio of inactivation of inv(X) by RBG-banding was discordant between the two sisters, with the older sister having only 4.1% of cells carrying inactivated inv(X) while the proband had a 69.5% incidence of late replicating inv(X). Therefore, we suggest that the cause of azoospermia in the first case might be related to inversion X chromosome with positional effect. Also, the family of the second case showing normal phenotype of the balanced inv(X) might be not affected any positional effect of genes.

• Journal of the Mineralogical Society of Korea
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• 제3권1호
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• pp.7-17
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• 1990

화산 유리질 암석을 출발 물질로 사용하여 저온 ($80^{\circ}C$)에서 수열 처리하여 Na-P Na-X 및 Na-A 제올라이트를 합성하였다. 합성과정은 (1) 유리질 분말 시료와 알칼리 용액과의 용해.변질 반응에 의한 1차적인 Na-P의 합성 방식과 (2) 여기서 잔류된 규산질 모액에 Al(OH)3나 NaAlO2의 수용액을 공급하여 보다 고순도의 Na-P, Na-X 및 Na-A를 효과적으로 합성할 수 있었다. 원암의 암상과 조성은 제올라이트들의 화학 조성과 순도 및 백색도같은 물리적 특성에는 영향을 주지만, 합성된 제올라이트의 광물종을 규제하는 주된 요인은 아닌 것으로 해석된다. 합성된 제올라이트의 광물상은 반응 용액의 pH, Al(OH)4 및 Na+에 대한 농도 조건에 주로 의존되는 경향을 나타낸다. 또한 화산 유리질 암석을 제올라이트 합성원료로 활용하는 데에 있어서 (2)와 같음 합성 방안이 보완적으로 시행되면 그 생산성과 효율성을 제고시킬 수 있을 것으로 여겨진다.

• Bulletin of the Korean Mathematical Society
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• 제38권4호
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• pp.657-662
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• 2001

It is proved that if for each n, $1\leqp_n\leq2 \;and \;the(p_n, p’_n)$ Clarkson inequality holds in each Banach space X$_{n}$ then the (t, t’) Clarkson inequality holds in ($\sum^\infty_{n=1}\; X_n)_r, \;the \ell^r-sum \;of\; X_n’s,\; where\; 1\leqr<\infty,\; t=min{p, r, r’} \;and \;p = \;inf{p_n}.$ The (p, p’) Clarkson inequality is preserved by quotient maps and a new proof of a Takahashi-Kato theorem stating that the (p, p’) Clarkson inequality holds in a Banach space X if and only if it holds in its dual space $X_*$ is given.n.

• Bulletin of the Korean Chemical Society
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• 제18권7호
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• pp.743-749
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• 1997

Local structure refinement of the BaFe1-xSnxO3-y system (x=0.00-0.50) has been carried out with Fe K-edge x-ray absorpion spectroscopic studies. It is found out that the Fe ions are placed in two different symmetric sites such as tetrahedral and octahedral sites in the compounds by comparison with Fe K-edge x-ray absorption near edge structure (XANES) spectrum of the γ-Fe2O3 compound as a reference. Small absorption peaks of dipole-forbiden transitions appear at a pre-edge region of 7111 eV due to the existence of Fe ions in the tetrahedral and octahedral sites. The peak intensity decreases with the substitution amount of Sn ion. Three different absorption peaks of 1s→4p dipole-allowed transition appear on the energy region between 7123 and 7131 eV. The peaks correspond to 1s→4p main transition of Fe ions in tetrahedral and octahedral sites and 1s→4p transition followed by the shakedown process of ligand to metal charge transfer. The bond distances between Fe ions in the tetrahedral site and nearest neighboring oxygen atom (Fe-4O), and those in octahedral site (Fe-6O) are determined with the extended x-ray absorption fine structure (EXAFS) analysis. Two different interatomic distances increase with the substitution amount of Sn ion and also the bond lengths of Fe-4O are shorter than those of Fe-6O in all compounds.

• Korean Journal of Environmental Biology
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• 제17권1호
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• pp.27-34
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• 1999

In order to obtain necessary data for the use of hydrophytes to improve water quality of artificial lakes, production and nutrients absorption by some macrohydrophytes were investigated in a small water course at Woongcheon, Chungnam Province. The maximum above-ground standing biomass of Phragmites communis, Typha angustifolia and Zizania latifolia stand were 3,504 g/m$x^2$, 2,834 g/m$x^2$ and 3,125 g/m$x^2$, respectively. Estimated below-ground standing biomass of each stand were 9,671 g/m$x^2$,5,158 g/m$x^2$ and 5,813 g/m$x^2$, respectively. Concentration of nutrients in each organ was different among plant species. Maximum amount of standing nitrogen was the highest in the reed stand and that of standing phosphorus was the highest in the cattail stand. Amount of maximum standing nutrients are 2795.6 kgN/ha and 42.5 kgP/ha for the reed stand, 1,413 kg N/ha and 24.8 kgP/ha for the cattail stand and 1.901.1 kgN/ha and 38.4 kgP/ha for the wild rice stand, respectively. According to our investigation, it is concluded that reed, cattail and wild rice are suitable for water quality improvement of artificial lakes through nutrients absorption.

• Journal of the Korean Mathematical Society
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• 제44권4호
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• pp.787-797
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• 2007

In this paper, the following fourth-order rational difference equation $$x_{n+1}=\frac{{x_n^b}+x_n-2x_{n-3}^b+a}{{x_n^bx_{n-2}+x_{n-3}^b+a}$$, n=0, 1, 2,..., where a, b ${\in}$ [0, ${\infty}$) and the initial values $X_{-3},\;X_{-2},\;X_{-1},\;X_0\;{\in}\;(0,\;{\infty})$, is considered and the rule of its trajectory structure is described clearly out. Mainly, the lengths of positive and negative semicycles of its nontrivial solutions are found to occur periodically with prime period 15. The rule is $1^+,\;1^-,\;1^+,\;4^-,\;3^+,\;1^-,\;2^+,\;2^-$ in a period, by which the positive equilibrium point of the equation is verified to be globally asymptotically stable.

• Journal of The Korean Society of Grassland and Forage Science
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• 제7권3호
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• pp.162-167
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• 1987

This experiment was conducted to determine the effect of the feeding value for the wild legumes silage-making with additives. The chopped Kudzu (Puerarie thunbergii Bentham) of wild legumes was ensiled by the conventional method in the small experimental silo of 2 liters. The additives used in the present experiments were water (8%),water (8%) plus corn starch (3%) and water (8%) plus glucose (3%). These additives as well as that of control without additive were set up and these silage were compared with the conventional corn silage. The fermentative qualities and the characteristic of fiber (neutral detergent fiber, NDF; acid detergent fiber, ADF; acid detergent lignin, ADL) of silage produced was determined by chemical analysis, and dry matter digestibility (DMD) was evaluated by pepsin-cellulase technique. The results obtained are summarized as follows: 1 The weight of Kudzu silage was lost under the 10% for all the treatments. 2 In degree of pH for the Kudzu silages with glucose, starch, control and water treatments were high 3.80,4.04,4.57 and 5.34, respectively.