• Journal of Adhesion and Interface
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• v.24 no.4
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• pp.136-142
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• 2023

In this study, TEOS was used as a silica source, and a triblock copolymer (P123) was used as a template to produce mesoporous silica with a well-ordered hexagonal mesopore array through a self-assembly method and hydrothermal process under acidic condition. (Surfactant-extracted SBA-15). Surfactant-extracted SBA-15 showed the particle shape of a short rod with a size of approximately 980 nm. The surface area and pore diameter were 730 m²g^-1 and 70.8 Å, respectively. Meanwhile, aminosilane (3-aminopropyltriethoxysilane, APTES) was grafted into the mesopores using a post-synthesis method. Mesoporous silica (APTES-SBA-15) modified with aminosilane had a well-ordered pore structure (p6mm) and well-maintained the particle shape of short rods. The surface area and pore diameter of APTES-SBA-15 decreased to 350 m²g^-1 and 60.7 Å, respectively. APTES-modified mesoporous silica was treated with a solution of rare earth metal ions (Eu³⁺, Tb³⁺) to synthesize a mesoporous silica material in which rare earth metal complexes were introduced into the mesopores. (Eu/APTES-SBA-15, Tb/APTES-SBA-15) These materials exhibited characteristic photoluminescence spectra by λ_ex=250 nm. (⁵D₄→⁷F₅ (543.5 nm), ⁵D₄→⁷F₄ (583.5 nm), ⁵D₄→⁷F₃ (620.2 nm) transitions for Tb/APTES-SBA-15; ⁵D₀→⁷F₀ (577.7 nm), ⁵D₀→⁷F₁ (592.0 nm), ⁵D₀→⁷F₂ (614.9 nm), ⁵D₀→⁷F₃ (650.3 nm) and ⁵D₀→⁷F₄ (698.5 nm) transitions for Eu/APTES-SBA-15)

• Journal of Embryo Transfer
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• v.31 no.1
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• pp.27-32
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• 2016

This study was conducted to evaluate the effects of different volume ($100{\mu}l$ vs. 2 ml) of microdrop culture on B6D2F1 mice oogenesis. In the present study, B6D2F1/CrljOri $F_1$ mice were utilized in order to maximize oogenesis. Also we used TCM-199, Dulbecco's medified Eagle's medium (DMEM), embryo culture medium (Fertilization medium, Cleavage medium, Blastocyst medium), G series medium and One step medium. Blastulation rate was not different between groups ($58.4{\pm}2.9%$ vs. $61.2{\pm}4.8%$). Zona hatched rate ($38{\pm}15.4%$ vs. $27{\pm}3.4%$) and attached rate ($55{\pm}13.9%$ vs. $46{\pm}3.9%$) did not differ by the volume of culture media. Total cell numbers ($59.8{\pm}9.7$ vs. $70.3{\pm}8.7$), ICM cell numbers ($15.8{\pm}0.6$ vs. $16.8{\pm}1.5$), TE cell numbers ($44.0{\pm}9.7$ vs. $53.6{\pm}7.3$), % ICM ($26.4{\pm}2.9%$ vs. $23.8{\pm}3.3%$) and ICM:TE ratio ($1:2.8{\pm}0.4$ vs. $1:3.2{\pm}0.6$) were not different between groups (i.e., $100{\mu}l$ vs. 2 ml). These results show that the capacity of the culture medium did not effect the cell numbers of B6D2F1 mice blastocysts. In summary, these results can provide fundamental data to maximize culture condition for in vitro fertilization on B6D2F1 mice.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.8 s.111
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• pp.725-731
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• 2006

A novel design of frequency multiplier using a feedforward technique and a defected ground structure(DGS) is proposed. The feedforward loop in the proposed frequency multiplier suppresses the fundamental component $(f_0)$, the dumb-bell or spiral shaped DGS diminish unwanted harmonics such as second, third and fourth. Due to the combination of the feedforward structure and the DGS, only the multiplied frequency component$(2f_0,\;3f_0,\;4f_0)$ appears at the output port and the other unwanted components are suppressed excellently. The frequency multiplier is designed at 1 GHz $(f_0)$, by the proposed technique and measured. The measured output power of $2f_0,\;3f_0$ and $4f_0$ is -2.59 dBm, -5.36dBm and -4.57dBm, respectively, when the input power is 0dBm.

• Journal of the Korean Chemical Society
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• v.43 no.1
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• pp.52-57
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• 1999

The anionic complexes, [ln($C_6F_5)_4$]-, which are thermal and moisture sensitive, have been prepared by the reaction of In($C_6F_5)_3{\cdot}D(D=CH_3CN$, O($C_2H_5)_2$) with the system ($CH_3)_3SiC_6F_5$/CsF, $C_6F_5$MgBr or Cd($C_6F_5)_2$. The stable anionic indium(III) complexes are obtained through cation exchange with PNPCI ([PNP]= bis(triphenylphosphino)ammonium). The pure substance is obtained by column chromatography. These new anionic complexes are unambiguously identifed by NMR-spectroscopy, IR spectroscopy, molecular weight, DTA/TG and elemental analysis.

• Archives of Pharmacal Research
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• v.16 no.2
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• pp.164-167
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• 1993

Arylhydrazones of diethyl acetonedicarboxylate 3 was treated with fomaldehyde to 1-aryl-1, 4, 5, 6-tetrahyeheypyridazine derivatives 4a-f Cyclization of compound 4a-f by hydroxy-lamine afforded [3, 4-d] 1, 4, 5, 6-tetrahydropyridazine derivative 5a-f. Also, cyclization of compound 4c with semicarbazide gave pyrazolote [4, 3-c] pyridazine 6. On the other hand compound 3 reacted with ethylothofomate to give diethyl-1, 4-dihydro-1-arypyridazine-4-one-3, 5 dicaboxylate 7, which on treatment with hydrazine, semicarbazide and thiosemicarbazide gave pyridazine, amido and thioamido derivatives. The spectrl and antimicrobial data of these compounds 1-8 were studied.

• Archives of Pharmacal Research
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• v.15 no.3
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• pp.224-228
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• 1992

Arylhydrazones of diethylacetondicarboxylate 3 was treated with formaldehyde to give 1 aryl-4, 5, 6-trihydropyridaine derivatives 4a-f Cyclization of compound 4a-f by hydroxylamine afforded [3, 4d] 1, 3, 4, 5-tetrahydropyridazine derivatives 5a-f. Also cyclization of compound 4c with semicarbazide gave 1-amidopyrazolo-5-one-1-aryl-3-carboxypyridazine 6. On the other hand compounds 3 reacted with ethylorthoformate to give diethyl-1, 4-dihydro-1-arylpyridazine-4one-2.5 dicarboxylate 7, which on treatment with hydrazine. Semicarbazide and thiosemicarbazide gave pyridazine, amido and thioamido derivatives. The spectral and antimicrobial data of these compounds 1-8 were studied.

• Journal of the Korean Vacuum Society
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• v.5 no.4
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• pp.315-326
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• 1996

The electronic structures of 3d and 4d core-levels of rare-earth atoms in the insulating rare-earth (Sm, Eu, Gd, and Tb) compounds were studied with x-ray photoelectron spectroscopy(XPS). It is shown that the intrinsic satellite structure due to the hybridization disappears for chemically stable-earth trivalent heavy rare-earth insulating compounds as the hybridization between f electrons of rare-earth atoms and p electrons of anion atoms decreases due to the lanthanide contraction. Eu atoms at the surface of the stable insulating trivalent Eu compounds are found to be divalent. The satellite peak of Eu 3d core-level spectra at about 10eV higher binding energy side relative the main peak comes from the multiplet structures of $\underline{3d}4f^6$ configuration. The satellite structure appearing at about 15 eV higher binding energy side relative to the main peak in all insulating rare-earth compounds is due to an energy loss process of creating a plasmon.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1273-1276
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• 2011

Laponite samples intercalated with $Tb^{3+}$ or $Tb^{3+},Ce^{3+}$ ions were prepared by exchange of Na+ ions in interlayers with $Tb^{3+}$ or $Ce^{3+}$ ions. Strong green and weak blue emissions under vacuum ultraviolet (VUV) excitation (${\lambda}$ = 158 nm) were observed due to the $^5D_4{\rightarrow}^7F_J$ and $^5D_3{\rightarrow}^7F_J$ emission lines, respectively. $Tb^{3+}$ ions in an interlayer of laponite mainly existed in ion pairs or clusters, as evidenced by the concentration-dependent luminescence of the $Tb^{3+}$ ions on the relative intensities of the $^5D_3{\rightarrow}^7F_J$ and the $^5D_4{\rightarrow}^7F_J$ emission lines, due to the action of a cross-relaxation process. The addition of $Ce^{3+}$ ions increased the thermal stability of $Tb^{3+}$ intercalated laponite up to $650^{\circ}C$ and quenched the $^5D_3{\rightarrow}^7F_J$ emission lines, probably by promoting the formation of $Tb^{3+}$ ion pairs at relatively low $Tb^{3+}$ concentrations.

• The Korean Journal of Mycology
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• v.16 no.3
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• pp.157-161
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• 1988

The vegetative nuclear divisions in hyphae and chromosome numbers were studied with the aid of Giemsa-HCl techniques from 10 strains of Fusarium oxysporum. The entire nuclear division process occurred within an intact nuclear envelope like other fungus. The results confirmed that 2 strains(F. oxysporum S Hongchun D2, F. oxysporum S Jinyang 4) were n=4; 3 strains(F. oxysporum f. sp. lini KFCC 32585, F. oxysporum f. sp. melongenae KFCC 34743 and F. oxysporum f. sp. raphani) n=5; 2 strains(F. oxysporum f. sp. vasinfectum, and F. oxysporum f. sp. mori KFCC 34742) n=6; 3 strains(F. oxysporum f. sp. cucumerium, F. oxysporum f. sp.niveum, and F. oxysporum f. sp. pisi) n=7.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.217-222
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• 1985

The yield responses of three isogenic lines in plant type of paddy rice(open-, spread- and broom-type) as affected by combined treatments of transplanting densities (47.62, 22.22, 15.15, 11.11 and 8.33 hills per sq. meter) and rates of fertilizer application (0, 0.5, 1.0 and 1.5 folds of standard rate) were studied by using of the partial differentiations by planting density(D):df(D,F)/dD, fertilizer rate(F):df(D,F)/dF, and their interaction(DXF):d$^2$ f(D,F)/dDdF from the multiple regression polynominal equations. Under the condition of wider planting, the broom-type showed most prominent and sensitive responses in yield among others. Also the action of transplanting density in the broom-type were positive both at lower and higher densities. Under the lower densities, the broom-type represented positive actions both at lower and higher rates of fertilizer application. Whereas the interactions between the density and fertilizer rate under the lower densities were rather negative. To achieve the labor-saving by lower transplanting density(11-14 hills per sq. meter), the amount of fertilizer rates were estimated as 1.3-1.5 folds much of the standard in the open-type, whereas more than 1.5 folds in the broom-type. Thus, the potentials to absorb more amounts of fertilizer may explain the compensating function of the broom-type for equivalent yields of the standards at reduced transplanting densities.