• Journal of the Korean institute of surface engineering
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• v.34 no.5
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• pp.403-408
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• 2001

In this work, the cyclic perfluorinated ether (c-C$_4$F$_{8}$O) with very high destructive removal efficiency (DRE) than other alternative gases, such as $C_3$F$_{8}$, c-C$_4$F$_{8}$ and NF$_3$ was used as an alternative process chemical. The plasma cleaning of silicon nitride using gas mixtures of c-C$_4$F$_{8}$O/O$_2$ and c-C$_4$F$_{8}$O/O$_2$+ $N_2$ was investigated in order to evaluate the effects of adding $N_2$ to c-C$_4$F$_{8}$O/O$_2$ on the global warming effects. Under optimum condition, the emitted net perfluorocompounds (PFCs) during cleaning of silicon nitride were quantified and then the effects of additive $N_2$ by obtaining the destructive removal efficiency (DRE) and the million metric tons of carbon equivalent (MMT-CE) were calculated. DRE and MMTCE were obtained by evaluating the volumetric emission using. Fourier transform-infrared spectroscopy (FT-IR). During the cleaning using c-C$_4$F$_{8}$O/O$_2$+$N_2$, DRE values as high as (equation omitted) 98% were obtained and MMTCE values were reduced by as high as 70% compared to the case of $C_2$F$_{6}$O$_2$. Recombination characteristics were indirectly investigated by combining the measurements of species in the chamber using optical emission spectroscopy (OES), before and after the cleaning, in order to understand any correlation between plasma and emission characteristics as well as cleaning rate of silicon nitride.silicon nitride.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.463-467
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• 2009

Interspecific hybrid plants between Allium cepa L. (2n=2X=16) and A. fistulosum L. (2n=2X=16)and their backcross lines were developed by artificial pollination in order to introduce new desirable characters of A, cepa to A. fistulosum. The 2C nuclear DNA content has been estimated by flow cytometry in 5 Allium fistulosum inbreed lines, 2 interspecific hybrid lines of A. cepa${\times}$A. fistulosum and 34 their backcross lines $BC_1F_1$ to $BC_2F_2$, using propidium iodide (PI) as a fluorescence dye. Estimated 2C DNA values ranged from 22.2 pg to 23.7 pg in 5 A. fistulosum inbreed lines, 37.9 pg in F1 hybrid between A. cepa and A. fistulosum, 24.3 pg to 27.3 pg in 7 backcross lines in $BC_1F_1$, 21.9 pg to 24.4 pg in 9 $BC_1F_2$, 22.9 pg to 25.1 pg in 14 $BC_2F_1$, 22.6 pg to 23.4 pg in 4 $BC_2F_2$. This study showed mean 2C nuclear DNA content of $F_1$ hybrid was higher than their backcross progeny lines, while it was lower than female parental line, A. cepa (2C DNA=33.2 pg). Mean 2C DNA content of backcross lines, $BC_1F_1$ to $BC_2F_2$ was not significantly different but their 2C DNA contents in the more progress generation from $BC_1F_1$ to $BC_2F_2$ were reduced.

• Korean Journal of Optics and Photonics
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• v.6 no.3
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• pp.201-213
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• 1995

By the use of computer simulation including collisional mixing kinetic processes of the B- and C-state in the upper laser level the output characteristics of electron-beam pumped XeF$(C\rightarrowA$ excimer laser are analyzed. We compared the results between experiments and simulations for the $XeF^*(C)$ formation that correlated the number of densities of the $XeF^*(B)$. We obtained good agreement$(28.5 mJ\pm5%)$ with comparisons between experiment and simulation and confirmed the optimal gas mixing ratio of $Xe/F_2/Ar=5.26/0.49/94.28%$ at atmospheric pressure laser medium under the condition of 70 ns [FWHM] electron-beam (800 kV, 21 kA). Also through the simulation we have investigated that the $XeF^*(C)$ formation channel, the $XeF^*(C)$ relaxation channel, and the absorption channel of bluegreen wavelength region as a function of F2 halogen donor and Xe partial pressure. ssure.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.4
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• pp.274-280
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• 2001

The chemical forms of calcium compounds in perilla leaves and their changes after harvest were investigated. The four types of calcium compounds extracted were as follows: water soluble calcium(F-I: mainly water soluble organic acid salts and calcium ion), IN-sodium chloride soluble calcium(F-II: calcium-pectate and calcium-carbonate), 2%-acetic acid soluble calcium(F-III: calcium-phosphate), and 5%-hydrochloric acid soluble calcium(F-IV: calcium-oxalate). The calcium content of perilla leaves was not found to vary with their age. Relatively high levels of F-l (28.4~39.5) and F-II (34.4~47.4) were found in young and mature leaves while the F-IV constituted 15.6~21.6% of the total calcium. The F-IV calcium contents of perilla. spinach and jaso were 16.8, 42.4 and 22.3%, respectively. In contrast to calcium. magnesium existed as water soluble magnesium at the highest content of 90.6% in spinach while 62.9% and 16.8% of the total magnesium existed as water soluble magnesium in perilla and jaso, repectively. The change in vitamin C and F-IV calcium content were examined for 7 days after harvest. Vitamin C content decreased slowly at the beginning but rapidly from the 4th day after harvest. On the other hand, the F-IV calcium content increased slowly at the beginning and rapidly from the 4th day of observation. This result suggests that the increase in F-IV calcium is related to the decrease in vitamin C content. This phenomena was more distinctly observed at 2$0^{\circ}C$ than 5$^{\circ}C$.

• Journal of applied mathematics & informatics
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• v.28 no.5_6
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• pp.1315-1322
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• 2010

Let D be a plane domain whose boundary consists of n components and $C_1$, $C_2$ two boundary components of D. We consider the family $F_1$ of conformal mappings f satisfying f(D) $\subset$ {1 < |w| < ${\mu}(f)$}, $f(C_1)=\{|w|=1\}$, $f(C_2)=\{|w|={\mu}(f)\}$. There are conformal mappings $g_0$, $g_1({\in}F_1)$ onto a radial and a circular slit annulus respectively. We obtain the following theorem, $$\{{\mu}(f)|f\;{\in}\;F_1\}=\{\mu|\mu(g_1)\;{\leq}\;{\mu}\;{\leq}\;{\mu}(g_0)\}$$. And we consider the family $F_n$ of conformal mappings $\tilde{f}$ from D onto a covering surfaces of the Riemann sphere satisfying some conditions. We obtain the following theorems, {$\mu|1$ < ${\mu}\;{\leq}\;{\mu}(g_1)$} ${\subset}\;\{{\mu}(\tilde{f})|\tilde{f}\;{\in}\;F_2\}\;{\subset}\;\{{\mu}(\tilde{f})|\tilde{f}\;{\in}\;F_n\}$ and ${\mu}(\tilde{f})\;{\leq}\;{\mu}(g_0)^n$.

• Korean Chemical Engineering Research
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• v.59 no.2
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• pp.254-259
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• 2021

Optical and electrical characteristics of the fluorocarbon films deposited in a high-density C4F8 plasma under various source powers and pressures were investigated. The F/C ratio of the fluorocarbon film deposited in a high-density C4F8 plasma increased with increasing source power and decreasing pressure due to two-step deposition mechanism. The change in the F/C ratio of the film directly affected the optical and electrical characteristics of the fluorocarbon films deposited in a high-density C4F8 plasma. The refractive index of the fluorocarbon film increased with decreasing source power and increasing pressure contrary to the dependence of the film's F/C ratio on the source power and pressure. This was because the increase in the F/C ratio suppressed electronic polarization and weakened the network structures of the film. The resistivity of the fluorocarbon film showed the same behavior as its F/C ratio. In other words, the resistivity increased with increasing source power and decreasing pressure, resulting from stronger repellence of electrons at higher F/C ratios. This work offers the feasibility of the use of the fluorocarbon films deposited in a high-density C4F8 plasma as an alternative to low dielectric constant materials because the optical and electrical properties of the fluorocarbon film can be directly controlled by its F/C ratio.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.205-213
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• 2011

The Folin-Ciocalteu (F-C) reagent has been extensively used for quantifying total phenolic contents in many different types of food materials. Since several different procedures of the assay methods using the F-C reagent have been applied, we investigated changes in reactivity of various phenolic compounds with the F-C reagent under three different assay conditions and factors affecting reactivity. Among 10 standard compounds tested, compounds with high hydroxyl density (number of -OH/molecular weight) showed a largely different response according to addition sequence of the F-C reagent or $Na_2CO_3$. Preincubation in $Na_2CO_3$ significantly reduced the reactivity of the phenolic compounds bearing galloyl moiety (e.g. gallic acid, tannic acid, and epigallocatechin-3-gallate) with the F-C reagent, while monophenol compounds including ferulic acid and sinapinic acid were more stable as compared to diphenols. There was little change in response to the F-C reagent of all phenolic compounds incubated in acidic pH; their reactivity except ferulic acid was reduced significantly when incubated in neutral or alkaline pH. Changes in reactivity of gallic acid incubated in $Na_2CO_3$ or neutral/alkaline pH conditions were the most prominent. $H_2O_2$ generated from phenolic compounds did not affect the reaction with the F-C reagents. The present results suggest that reactivity of different phenolic compounds with F-C reagent was affected considerably by different procedures of the assay, and the total phenolic contents could be fluctuated according to standard compounds and assay scheme.

• Korean Journal of Optics and Photonics
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• v.6 no.3
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• pp.214-221
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• 1995

When the broad pressure region (0.5-3.5 atm) of laser media is pumped by 70 ns [FWHM] electronbeam accelerator (800 kV, 21 kA), the correlation between free-runnuing XeF$(C\rightarrowA$ excimer laser output and Xe concentration are studied. The resonator consisted of dichroic output coupler, and the laser output is optimized with laser media $(Xe/F_2/Ar)$ as functions of total pressure and gas mixing ratio. Under the condition of F2 0.46% fixed, the laser intrinsic efficiencies of 0.38%, 1.03%, and 0.29% are obtained at 1. 2, and 3 atm, respectively. So then the peaks of laser intrinsic efficiency occured to the higher Xe concentration with decreasing total gas pressure. By analyzing the kinetics for the $XeF^*(C)$ formation efficiency and XeF$(C\rightarrowA$ laser extraction efficiency the dependence of Xe concentration on their correlation is explained. As the results we propose efficient operation of an atmosphericpressure XeF$(C\rightarrowA$ laser. laser.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.131-134
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• 2003

[ $ZnWO_4$ ] shows excellent frequency selectivity due to its high quality factor($Q{\times}f$) at microwave frequencies. However, in order to use $ZnWO_4$ as multilayered wireless communication components, its other properties such as sintering temperature($1050^{\circ}C$), ${\tau}_f$ ($-70ppm/^{\circ}C$) and ${\varepsilon}_r(15.5)$ should be modified. In present study, $TiO_2$ and LiF were used to improve the microwave dielectric and sintering properties of $ZnWO_4$. $TiO_2$ additions to $ZnWO_4$ changed ${\tau}_f$ from negative to positive value, and also increased ${\varepsilon}_r$ due to its high ${\tau}_f$ ($+400ppm/^{\circ}C$) and ${\varepsilon}_r$(100). At 20 mol% $TiO_2$ addition, ${\tau}_f$ was controlled to near zero $ppm/^{\circ}C$ with ${\varepsilon}_r=19.4$ and $Q{\times}f=50000GHz$. However, the sintering temperature was still high to $1100^{\circ}C$. LiF addition to the $ZnWO_4+TiO_2$ mixture was greatly reduced the sintering temperature from $1100^{\circ}C$ to $850^{\circ}C$ due to liquid phase formation. Also LiF addition decreased the ${\tau}_f$ value due to its high negative ${\tau}_f$ value. Therefore, by controlling the $TiO_2$ and LiF amount, temperature stable LTCC material in the $ZnWO_4$-TiO_2-LiF$ system could be fabricated.

• Journal of the Korean Home Economics Association
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• v.28 no.4
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• pp.1.1-13
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• 1990

Authors have performed the sensory evaluation tests according to each given items after selecting various lines in order to assess the visual effects by the lines in cloth designing. The evaluations were done by means of ranking tests followed by paired comparison tests. The results obtained were as follows : 1. In the item in than "Shoulder width looks wide", the design C3 showed the best visual effect, and then B1, F8, and A5 comes in order. In "Shoulder width looks narrow", they were A2, F5, F7, and B2 in order. 2. In "Bust looks big", the effect was best in F9, and then B1, F5, C3, and A5 and order. "Bust looks small" item showed A3, C1, and F1 in order. 3. In "Waist looks thick", they were B2, D1, and F7 while in "Waist looks thin", they were B3, F8, and D6 in order. 4. In the item in that "Hip looks big", the best effect was in F9, and then E3, C2, and B4 in order. In "Hip looks small", the best one was C1, and then comes. E1, F6, and F8. 5. In "Upper body looks thick", they were D2, D4, F8, C3 and A5 in order whild in "Upper body looks thin", they were A1, F5, and D7 in order. 6. In the item "Lower body lookds thick", they were F9, C2, E3, B3, and D3 in order. In "Lower body looks thin", the best one was C1, and then D1, E2, F6, and F8 comes in order. 7. In "whole body looks thick", they were F9, F3, D3, and A5, and in "Whole body looks thin", they were F5, A1, C1, and D6 in order. 8. In "Height looks tall", the effects were in order of A4, D6, E1, and F7 while in "Height looks short", they were E3, F9, B4, D2, and D1. 8. In "Height looks tall", the effects were in order of A4, D6, E1, and F7 while in "Height looks short", they were E3, F9, B4, D2, and D1. F9, B4, D2, and D1.