• Title/Summary/Keyword: f-stable

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Preservation Experiment of Hibernating Silkworm Eggs by 2 Year Cold Refrigeration (월년잠종의 2년간 냉장에 의한 보존 시험)

  • Sohn, Bong-Hee;Kang, Pil-Don;Lee, Sang-Uk;Kim, Yong-Soon
    • Journal of Sericultural and Entomological Science
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    • v.46 no.2
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    • pp.65-71
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    • 2004
  • Long term preservation experiment through refrigeration was conducted for 2 year on 300 lines of silkworm races preserved, as one method for the development of long term safe preservation technique. Experiment with 6 treatments was conducted for 680 days from July 1 st 2000 to May 1st 2002. Embryonic development was conducted to each treatment. There are no differences among treatments and races in 400 days preservation, the stage of whole embryonic development was Eul B and condition of eggs was good. In 650 days preservation experiment, differences were reveled among races and treatment, the level of whole embryonic development was Byeong A and condition of eggs was good. The order of embryonic development is European races >Tropical, Korean races >Japanese, Chinese races, thus European races showed fast embryonic development. Control(treatment A) and treatment C showed faster development than other treatments. And treatment D and F showed stable individual stage among all treatments. The test of shape characteristics and embryo which were conducted in hatching period showed 61% of high line succession possibility in average of 6 treatments. But treatment A and B showed no hatching, 3 lines of treatment C, 48 lines of treatment D, 1 line of treatment E, and 29 lines of treatment F showed slow development. And treatments D and F which showed stable embryo condition had highest possibility. The two treatments D and F showed good result among six treatments, and the preservation period of treatment D and F are 235 days and 310 days, and exposure period in $-2.5^{\circ}C$...was longer than other treatments. Numbers of hatched lines of treatment D and F are 48 and 29, and occupied 15.6% and 9.4% of all tested lines, respectively. Average hatching ratio of treatment D and F were 54.% and 71.6%, and average dead egg ratio were 12.6% and 2.4%, respectively. These results show that average ratio of hatching dead eggs in treatment D and F are higher than general line. Thus reconsideration of hatching condition on treatment D and F is needed.

Spectroscopic Studies on Electroless Deposition of Copper on Hydrogen-Terminated Si(111) Surface in NH4F Solution Containing Cu(II) Ions

  • Lee, In-Churl;Bae, Sang-Eun;Song, Moon-Bong;Lee, Jong-Soon;Paek, Se-Hwan;J.Lee, Chi-Woo
    • Bulletin of the Korean Chemical Society
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    • v.25 no.2
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    • pp.167-171
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    • 2004
  • The electroless deposition of copper on the hydrogen-terminated Si(111) surface was investigated by means of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, scanning tunneling microscopy (STM), and energy-dispersive spectroscopy (EDS). The hydrogen-terminated Si(111) surface prepared was stable under air atmosphere for a day or more. It was found from ATR-FTIR that two bands centered at 2000 and 2260 $cm^{-1}$ appeared after the H-Si(111) surface was immersed in 40% $NH_4F$ solution containing 10 mM $Cu^{2+}$. On the other hand, STM image included the copper islands with a height of 5 nm and a diameter of 10-20 nm. The EDS data displayed the presence of copper, silicon and oxygen species. The results were rationalized in terms of the redox reaction of surface Si atoms and $Cu^{2+}$ ions in solutions, which are changed into $Si(OH)_x(F)_y$ containing $SiF_6^{2-}$ ions and neutral copper islands.

Electronic and magnetic structure calculations of $La_2MnFeO_6$ with double perovskite oxide (이중 페로브스카이트 구조 $La_2MnFeO_6$의 전자구조와 자기구조 계산)

  • 박기택
    • Journal of the Korean Magnetics Society
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    • v.10 no.3
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    • pp.139-142
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    • 2000
  • We present results based on FLAPW local spin density(LSD) calculations of double perovskite structure oxide L $a_2$MnFe $O_{6}$ . The total energy calculations with various spin structures show that this material has a stable ferromagnetic spin configuration. The ionic state of transition metals depend on the spin configuration $_Mn^{4+}$ and F $e^{2+}$ for ferromagnetic structure, M $n^{3+}$ and F $e^{3+}$ for ferrimagnetic structure). It is explained by super exchange interaction between transition metals. The calculated magnetic structure is well matched with recent experimental result.ult.t.

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Effects of base token for stimuli manipulation on the perception of Korean stops among native and non-native listeners

  • Oh, Eunjin
    • Phonetics and Speech Sciences
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    • v.12 no.1
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    • pp.43-50
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    • 2020
  • This study investigated whether listeners' perceptual patterns varied according to base token selected for stimuli manipulation. Voice onset time (VOT) and fundamental frequency (F0) values were orthogonally manipulated, each in seven steps, using naturally produced words that contained a lenis (/kan/) and an aspirated (/khan/) stop in Seoul Korean. Both native and non-native groups showed significantly higher numbers of aspirated responses for the stimuli constructed with /khan/, evidencing the use of minor cues left in the stimuli after manipulation. For the native group the use of the VOT and F0 cues in the stop categorization did not differ depending on whether the base token included the lenis or aspirated stop, indicating that the results of previous studies remain tenable that investigated the relative importance of the acoustic cues in the native listener perception of the Korean stop contrasts by using one base token for manipulating perceptual stimuli. For the non-native group, the use patterns of the F0 cue differed as a function of base token selected. Some findings indicated that listeners used alternative cues to identify the stop contrast when major cues sound ambiguous. The use of the manipulated VOT and F0 cues by the non-native group was not native-like, suggesting that non-native listeners may have perceived the minor cues as stable in the context of the manipulated cue combinations.

Effect of Favorite Music Therapy on Stress Response in Patients Undergoing Hysterectomy (선호음악요법이 자궁절제술 환자의 스트레스 반응에 미치는 효과)

  • Yang, Jung Lim;Yoo, Kwang Soo
    • Journal of Korean Clinical Nursing Research
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    • v.23 no.1
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    • pp.30-39
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    • 2017
  • Purpose: The aim of this study was to evaluate the effects of favorite music therapy on the stress response of hysterectomy patients undergoing general anesthesia. Methods: Date were collected from June 29, 2015 to January 18, 2016 and the participants were 79 hysterectomy patients (experimental group 40 and control group 39). The experimental group listened to their favorite music through earphones from the moment they entered the surgical waiting room until they exited from the post anesthesia care unit. Results: There were statistically significant differences in anxiety (F=15.92, p<.001), systolic blood pressure (F=4.23, p=.008), diastolic blood pressure (F=3.07, p=.033), and heart rate (F=19.93, p<.001) between participants in the experimental group and the control group according to measurement times. Conclusion: The study results show that favorite music therapy considering patients' preferences is effective in reducing anxiety among patients undergoing a hysterectomy under general anesthesia, thus leading to a stable change in their blood pressure and heart rate.

Composite Materials with MWCNTs and Conducting Polymer Nanorods and their Application as Supercapacitors

  • Liua, Lichun;Yoo, Sang-Hoon;Park, Sung-Ho
    • Journal of Electrochemical Science and Technology
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    • v.1 no.1
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    • pp.25-30
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    • 2010
  • This study demonstrated the synthesis of high-surface-area metal-free carbonaceous electrodes (CE) from anodic aluminum oxide (AAO) templates, and their application as supercapacitors. Multi-walled Carbon nanotubes (MWCNTs) were interwoven into a porous network sheet that was attached to one side of AAO template through a vacuum filtration of the homogeneously dispersed MWCNT toluene solution. Subsequently, the conducting polymer was electrochemically grown into the porous MWCNT network and nanochannels of AAO, leading to the formation of a carbonaceous metal-free film electrode with a high surface area in the given geometrical surface area. Typical conducting polymers such as polypyrrole (PPY) and poly(3,4-ethylenedioxythiophene) (PEDOT) were examined as model systems, and the resulting electrodes were investigated as supercapacitors (SCs). These SCs exhibited stable, high capacitances, with values as high as 554 F/g, 1.08 F/$cm^2$ for PPY and 237 F/g, 0.98 F/$cm^2$ for PEDOT, that were normalized by both the mass and geometric area.

A Study on the Evaluation of Oxidation Resistance of Nitride Films in DRAM Capacitors (DRAM 커패시터의 질화막 내산화성 평가에 관한 연구)

  • Chung, Yeun-Gun;Kang, Seong-Jun;Joung, Yang-Hee
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.3
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    • pp.451-456
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    • 2021
  • In order to improve the cell capacitance and scale down in capacitors of semiconductor memory devices, a stacked ONO structure has been introduced as a dielectric layer and thinning of these layers has been attempted continuously. However, many problems have emerged in the manufacturing process. In this study, L/L LPCVD system was used to suppress the growth of natural oxide film of about 10 Å, which was able to secure the capacitance of 3fF / cell. In addition, we investigated the effect of thinning of the dielectric film on the abnormal oxidation of the nitride film, and proposed a stable process control method for forming the dielectric film to ensure oxidation resistance.

Purification and Characterization of Chinese Cabbage Pectinesterase (배추 펙틴에스테라제의 정제 및 특성)

  • Ko, Young-Hwan;Park, Kwan-Hwa
    • Korean Journal of Food Science and Technology
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    • v.16 no.2
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    • pp.235-241
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    • 1984
  • Two fractions of pectinesterase from Chinese cabbage were isolated by ammonium sulfate fractionation, ion exchange chromatography on DEAE-cellulose and Sephadex G-150 gel filtration. The fraction F-A and F-B were purified approximately 340- and 10-fold. The similar salt effects and pH optima (pH 7.5-8.0) were obtained for the two pectinesterase fractions. The maximum activity of both two. fractions were obtained at 20-50mM of divalent rations and at 250mM of monovalent rations. The apparent Michaelis constant of the F-A was 0.01% for citrus pectin. The temperature optima for F-A and F-B were $48^{\circ}$ and $55^{\circ}C$, respectively and both fractions were stable in the region of pH 5.0-8.0 at room temperature. The thermal inactivation of the two fractions followed the first order reaction kinetics. From D and Z-values obtained the thermal resistance of the two fractions were characterized.

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The Electron Trap Analysis in Thermoluminescent LiF Crystal

  • Park, Dae-Yoon;Ko, Chung-Duck;Lee, Sang-Soo
    • Nuclear Engineering and Technology
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    • v.4 no.3
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    • pp.214-222
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    • 1972
  • In the optic,11 grade LiF crystal, the electron traps corresponding to the thermoluminescence(abbreviated to TL) glow peak develop as irradiation dose is increased. Originally the electron trap of the crystal has two levels but as the dose reaches to the order of 10$^4$rontgen, it attains five levels as observed in the TL glow curves. The five trap depths are determined from the glow peak temperatures for two different heating rates, $\theta$=6.6$^{\circ}C$/sec and 3.4$^{\circ}C$/sec. The electron trap depths have the following values E$_1$=0.79 eV, E$_2$=0.93 eV, E$_3$=1.02 eV, E$_4$=1.35 eV, E$_{5}$=1.69eV. The special feature of thermoluminescence of optical grade LiF is that the traps, except E$_1$and E$_2$corresponding to 12$0^{\circ}C$ glow peak and 15$0^{\circ}C$ glow peak for $\theta$=6.6$^{\circ}C$/sec, have severe thermal instability, namely E$_3$, E$_4$and E$_{5}$ levels disappear during bleaching process. These defects in the optical grade LiF crystal seem annealed out during the course of TL measurement. The fresh or long time unused LiF(Mg) crystal shows only two glow peaks at 17$0^{\circ}C$ and 23$0^{\circ}C$ for $\theta$=6.6$^{\circ}C$/sec, but upon sensitization with r-ray irradiation, it converts to the six glow peak state. The four electron traps, E$_1$, E$_2$, E$_3$, and E$_{6}$ created by r-ray irradiation and corresponding to the glow peaks at T=10$0^{\circ}C$ 13$0^{\circ}C$, 15$0^{\circ}C$ and 29$0^{\circ}C$ are stable and not easily annealed out thermally, The sensitization essentially required to LiF(Mg) dosimeter is to give the crystal the stable six levels in the electron trap. In optical grade LiF, the plot between logarithm of total TL output versus logarithm of r-ray dose gives more supra-linear feature than that of LiF(Mg). However, if one takes the height of 12$0^{\circ}C$ glow peak(S=6.6$^{\circ}C$/sec), instead of the total TL output, the curve becomes close to that of LiF(Mg).

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Molecular Cloning and Nucleotide Sequence of the Gene Encoding Fusion(F) Protein of the Thermostable Newcastle Disease Virus Isolated from a Diseased Pheasant (꿩에서 분리된 Newcastle Disease Virus 내열성주 (CBP)의 Fusion(F) 유전자 클론닝과 염기서열 분석)

  • Chang, Kyung-Soo;Jun, Moo-Hyung;Song, Hee-Jong;Kim, Kui-Hyun;Park, Jong-Hyeon
    • The Journal of Korean Society of Virology
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    • v.28 no.3
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    • pp.233-245
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    • 1998
  • The gene encoding F protein of CBP-1 strain, a heat-stable Newcastle disease virus (NDV) isolated from the diseased pheasants in Korea, was characterized by reverse transcription-polymerase chain reaction (RT-PCR), nucleotide and amino acid sequences. Virus RNA was prepared from the chorioallatoic fluid infected with NDV CBP-1 virus and cDNA was amplified by RT-PCR, cloned and sequenced to analyze. The PCR was sensitive as to detect the virus titer above $2^5$ hemagglutination unit. 1.7kb (1,707bp) size of the cDNA was amplified and cloned into BamHI site of pVL1393 Baculo transfer vector. The nucleotide sequences for F protein were determined by dye terminator cyclic sequencing using four pairs of primers, and 553 amino acid sequences were predicted. In comparison of the nucleotide sequence of F gene of CBP-1 with those of other NDV strains, the homology revealed 88.8%, 98.5% and 98.7% with Kyojungwon (KJW), Texas GB and Beaudette C strains, respectively. As the deduced 553 amino acid sequences of F protein of CBP-1 were compared with those of other NDV strains, the homology appeared 89.9%, 98.7% and 98.9% with KJW, Texas GB and Beaudette C strains, respectively. The putative protease cleavage site (112-116) was R-R-Q-K-R, indicating that CBP-1 strain is velogenic type. The amino acid sequences include 6 sites of N-asparagine-linked glycosylation and 13 cysteine residues. These data indicate that the genotype of CBP-1 strain is more closely associated with the strains of Texas GB and Beaudette C than KJW strain.

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