• 한국식품과학회지
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• 제35권2호
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• pp.201-205
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• 2003

맥주 공장 부산물 효모의 용도를 다양화하기 위하여 효모 슬러리를 자가 소화시키고 상등액을 농축하여 조미료로 이용할 수 있는 효모추출물을 제조하였다. 맥주 효모의 세포벽에 부착되어 있는 호프 쓴맛 성분을 제거하기 위하여 효모 슬러리에 20%(w/v) NaOH 용액을 가하여 pH 9.8로 맞추고, 약 5분간 방치한 후 즉시 원심분리하면서 물로 세척하였다. 세척 후 효모 쓴맛 정도는 24.1 bitterness unit(BU)로서 threshold value 25.0 BU 미만이었다. 세척한 효모를 자가 소화시킨 후 수율[(수득한 효모추출물의 고형분 무게)/(투입 효모슬러리의 고형분 무게)${\times}100$]을 조사한 결과, 효모슬러리 농도를 $9{\sim}10%(w/w)$로 하고, 온도 $53^{\circ}C$, pH 6.8에서 20시간 이상 자가 소화시키면 34%(w/w)이상, 최대 38%(w/w)까지의 수율로 효모 추출물을 얻을 수 있었다.

• 대한간호학회지
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• 제25권2호
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• pp.279-294
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• 1995

The purpose of this study was to determine values and value changes in clinical nurses in clinical situations. A survey was conducted of 200 nurses of one of university hospital in Seoul Korea. This study was conducted between July 1 and July 5, 1994, using the Survey of Interpersonal Values (SIV) developed by L. V. Gordon, and standardized for Korea by Kyung Hye Lee & Eung Yun Hwang. The results of the study were as follows, 1. The clinical nurses surveyed showed Independence(18.32 : 63rd percentile) as their highest value, with Support(14.8 : 62nd percentile) next and then Benevolence(16.28 53rd percentile), Leadership(9.06 : 46th percentile), Conformity(18.15 : 42nd percentile) and Recognition(18.32 : 41s1 percentile) in that order in the area of general values. Using a standardised women's value Indicator, the clinical nurses value orientation was within the 32nd∼69th percentile indicating means found among Korean women in general. 2. Looking at how the values were related to demographics, Leadership was most highly valued among the 30∼34 year olds and least valued among the 25∼29 year olds. Unmarried nurses valued Independence more than married nurses did, and junior college graduate nurses valued Conformity more than baccalaureate graduate nurses did. 3. The study showed that the values of with less than one year (16.00) clinical experience were higher than those who had over 10 years (13.60) clinical experience (p<.05). Therefore clinical experience did not positively influence value orientation for clinical nurses. 4. There was no significant differences in the value of nurses in relation to their workplace, their level of motivation, or their aptitude. The study shows that clinical nurses have similar values compared with ordinary Korean women. This means that professional nurses may not be able to satisfy client needs and also that they do not have satisfaction and a positive attitude regarding the nursing profession. Therefore it is suggested that new strategies and continuing education programs be established to help clinical nurses fomulate higher values.

• Asian-Australasian Journal of Animal Sciences
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• 제14권5호
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• pp.697-700
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• 2001

A prolonged farrowing interval is common on small farms in Nepal and may be attributable to the absence of boar contact at the time of weaning. To examine whether synthetic boar pheromone spray might be of value to aid the stimulation and detection of estrus, 30 village farms, each with a single sow, were recruited into a field study. All sows entered the study on final weaning from their first lactation at 56 days post partum. For 13 treatment sows, a boar pheromone spray (SOA, Intervet, Boxmeer, The Netherlands) was applied each day after weaning whilst 17 other sows did not receive any stimulus (negative control). When estrous was detected by the farmer, sows were taken to the nearest boar for service. There was a significantly shorter weaning to re-mating interval for treatment sows (42.9 V 82.2 day, p<0.05), with a significantly higher proportion of treatment sows rebred by day 60 after weaning (p=0.024, Fishers Test). It is concluded that use of boar pheromones can improve reproductive efficiency of sows kept under Nepalese village conditions.

• Journal of electromagnetic engineering and science
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• 제4권4호
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• pp.156-161
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• 2004

The MMIC cascode VCO is designed, fabricated, and measured for Ku-band Low Noise Blcok(LNB) system using InGaP/GaAs HBT technology. The phase noise of -116.4 dBc/Hz at 1 MHz offset with output power of 1.3 dBm is obtained at 11.526 GHz by applying 3 V and 11 mA, which is comparatively better characteristics than compared with the different configuration VCOs fabricated with other technologies. The simulated results of oscillation frequency and second harmonic suppression agree with the measured results. The phase noise is improved due to the use of the smallest value of inductor in frequency determining network and the InGaP ledge function of the technology. The chip size of $830\time781\;{\mu}m^2$ is also achieved.

• 한국식품저장유통학회지
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• 제17권4호
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• pp.444-450
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• 2010

We investigated the quality of Dombaeki (shark meat) treated without salting (NS), with salting (S), air-packed (A), and vacuum-packed (V), during storage at $4^{\circ}C$ and $-18^{\circ}C$. We explored water holding capacity, elasticity, total bacterial counts, pH, titratable acidity level, volatile basic nitrogen (VBN) value, and drip loss. Water holding capacity and elasticity values were better when salting and vacuum-packaging were employed than when samples were not salted and were packaged in air. The total bacterial counts in SV meat were significantly lower than in other samples. The pH of all samples increased slowly during storage, and the pH values of NSA samples were significantly higher than the pH values of other samples. The VBN level and drip loss of SV meat were the lowest of all samples during storage. The results show that salted vacuum-packed meat was of better quality than that stored without salting, and air-packed, regardless of storage temperature.

• Transactions on Electrical and Electronic Materials
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• 제15권4호
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• pp.226-229
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• 2014

In this study, lead-free $(Ba_{0.85}Ca_{0.15})(Ti_{1-x}Zr_x)O_3$ ceramics and a bimorph-type piezoelectric actuator were fabricated using the normal oxide-mixed sintering method, and their dielectric properties, microstructure, and displacement properties were investigated. From the results of X-ray diffraction, the pattern of the specimen has a pure perovskite structure. In addition, no secondary impurity phases were found. The excellent piezoelectric coefficient of $d_{33}=454pC/N$, the electromechanical coupling factor $k_p=0.51$, the dielectric constant ${\varepsilon}_r=3,657$, the mechanical quality factor $Q_m=239$, and $T_c$(Tetragonal-Cubic) =$90^{\circ}C$ were shown at x= 0.085. ${\Delta}k_p/k_p20^{\circ}C$ and ${\Delta}f_r/f_r20^{\circ}C$ showed the maximum value of -0.255 and 0.111 at $-20^{\circ}C$ and $80^{\circ}C$, respectively. The maximum total-displacement was $60{\mu}m$ under the input voltage of 50 V. As a result, it is considered that lead-free $(Ba_{0.85}Ca_{0.15})(Ti_{1-x}Zr_x)O_3$ ceramics is a promising candidate for piezoelectric actuator application for x= 0.085.

• Journal of Microbiology
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• 제43권3호
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• pp.237-243
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• 2005

The protease purified from Bacillus cereus JH108 has the function of leucine specific endopeptidase. When measured by hydrolysis of synthetic substrate (N-succinyl-Ala-Ala-Pro-Leu-p-nitroanilide), the enzyme activity exhibited optimal activity at pH 9.0, $60^{\circ}C$. The endopeptidase activity was stimulated by $Ca^{++},\;Co^{++},\;Mn^{++},\;Mg^{++},\;and\;Ni^{++}$, and was inhibited by metal chelating agents such as EDTA, 1,10-phenanthroline, and EGTA. Addition of serine protease inhibitor, PMSF, resulted in the elimination of the activity. The endopeptidase activity was fully recovered from the inhibition of EDTA by the addition of 1 mM $Ca^{++}$, and was partially restored by $Co^{++}\;and\;Mn^{++}$, indicating that the enzyme was stabilized and activated by divalent cations and has a serine residue at the active site. Addition of $Ca^{++}$ increased the pH and heat stability of endopeptidase activity. These results show that endopeptidase requires calcium ions for activity and/or stability. A Lineweaver-Burk plot analysis indicated that the $K_m$ value of endopeptidase is 0.315 mM and $V_{max}$ is 0.222 ) is $0.222\;{\mu}mol$ of N-succinyl-Ala-Ala-Pro-Leu-p-nitroanilide per min. Bestatin was shown to act as a competitive inhibitor to the endopeptidase activity.

• 한국미생물·생명공학회지
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• 제23권4호
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• pp.446-453
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• 1995

$\alpha $-Arabinofuranosidase was produced by E. coli HB101 haboring the recombinant plasmid pKMG11 which contained the arfI gene of Bacillus stearothermophilus. The maximum production of the enzyme was observed when E. coli HB101 cells were grown at 37$\circ$C for 20 hours in the medium containing 0.5% arabinose, 1.0% tryptone, 0.5% yeast extract, and 1% NaCl. The $\ALPHA $-arabinofuranosidase produced was purified to homogeneity using a combination of 20-50% ammonium sulfate precipitation, DEAE-Sepharose CL-6B ion exchange column chromatography and Sepharose 6B-100 gel filtration. The purified enzyme was most active at 55$\circ$C and pH 6.5. The K$_{m}$ and V$_{max}$ values of the enzyme on $\rho $-nitrophenyl-$\alpha $-arabinofuranoside was determined to be 2.99 mM and 0.43 $\mu $mole/min (319.74 $\mu $mole/min/mg), respectively. The pI value was 4.5. The molecular weight of the native protein was estimated to be 289 kDa. The SDS-polyacrylamide gel clectrophoresis analysis suggested that the functional protein was a trimer of the 108 kDa identical subunits. The N-terminal amino acid sequence of the a-arabinofuranosidase was identified as X-Ser-Thr-Ala-Pro-Arg( \ulcorner )-Ala-Thr-Met-Val-Ile-Asp-X-Ala-Phe.

• 한국산림과학회지
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• 제76권3호
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• pp.230-240
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• 1987

인공산성우(人工酸性雨)가 은행(銀杏)나무의 엽면적(葉面積), 엽피해(葉被害), 엽록소함량(葉綠素含量) 및 엽조직(葉組織)의 광합성능(光合成能)에 미치는 영향(影響)을 구명(究明)하기 위하여, 천연(天然) 강우(降雨)를 차단(遮斷)하고 묘포토양(苗圃土壤), 혼합토양(混合土壤) 및 사질토양(砂質土壤)에 각각 분식(盆植)된 은행(銀杏)나무 유묘(幼苗)(1-0, half-sib)에 인공산성우(人工酸性雨)(황산(黃酸)과 질산(窒酸)을 3:1, v/v로 혼합(混合)하여 수도물로 희석한 pH2.0, 3.0, 4.0 및 5.0)와 수돗물(pH 6.4)을 생육기간중(生育其間中)(1985년(年) 4월(月) 28일(日)~10월(月) 19일(日))에 주(週) 3회(回), 매회(每回) 5mm씩 처리(處理)하여 얻어진 결과(結果)는 다음과 같다. 1. 산성우처리(酸性雨處理)에 의한 개체적(個體的) 엽면적(葉面積)의 변화(變化)는 토양별(土壤別)로 상이(相異)했으며, pH2.0 처리구(處理區)에서는 급격히 감소(減少)했으나, pH3.0이상의 처리구(處理區)들에서는 큰 차이(差異)가 없었다. 2. 엽피해율(葉被害率)은 처리산성우(處理酸性雨)의 pH 값이 낮을수록 피해엽율(被害葉率)과 피해면적(被害面積)이 증가(增加)하였다. 3. 엽조직(葉組織)의 엽록소함량(葉綠素含量)(총엽록소(總葉綠素), 엽록소(葉綠素) a 및 엽록소(葉綠素) b)은 6월(月)부터 10월(月)까지의 5회(回) 측정(測定)에서 토양간(土壤間)에 유의성(有意性)이 인정(認定)되었으며, 묘포토양(苗圃土壤)에서 가장 높았다. 처리산성우(處理酸性雨)의 pH 값이 낮을수록 처리초기(處理初期)에는 엽록소함량(葉綠素含量)이 높아졌으나, 7, 8월(月)부터는 급격히 감소(減少)하였다. 4. 엽조직(葉組織)의 광합성능(光合成能)은 7월(月), 8월(月) 및 9월(月) 측정(測定)에서 토양간(土壤間)에 차이(差異)가 있었으며, 묘포토양(苗圃土壤)에서 가장 높았다. 처리산성우(處理酸性雨)의 pH 값이 낮을수록 처리초기(處理初期)에는 높아졌으나, 7월(月)부터는 급격히 감소(減少)하였으며, 8월(月) 측정(測定)에서만 유의성(有意性)이 인정(認定)되었다.

• 대한화학회지
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• 제45권3호
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• pp.242-246
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• 2001

사성분계 thiophosphates, $A_2NiP_2S_6>(A=Rb$, Cs)를 halide fluxes 법으로 합성하였으며 단결정 X-ray 회절방법으로 결정 구조를 해석하였다. 이 화합물들을 $C_{2h}^5-P2_1/n$ 의 공간군을 가지며, $Rb_2NiP_2S_6$의 경우 a=5.960(2), b=12.323(4), $c=7.491(3)\AA$, $\beta=97.05(3)^{\circ}$, $V=546.0(3)\AA^3$이고$Cs_2NiP_2S_6$의 경우 a=5.957(4),b=12.696(7), $c=7.679(4)\AA$, $\beta=93.60(5)^{\circ}$, $V=579.7(5)\AA^3$인 격자상수를 갖는다. 이 두화합물은 동일한 결정 구조를 갖는다. 이들의 구조는 결정학적인 a축을 따라 성장한 1차원적인 무한사슬 $_{\infty}^1[NiP_2S_6^{2-}]$로 구성되어 있으며 이 사슬들은 알칼리 금속과의 정전기적 인력을 통하여 안정화 되어있다. Ni원자는 6개의 S원자에 의해 팔면체 배위를 하고 있고, Ni$S_6$팔면체는 $[P_2S_6^{4-}]$ 음이온 3개의 $\mu-S$ 원자들에 의해 연결되어 무한 1차원적인 사슬을 형성한다. $Cs_2NiP_2S_6$에 대한 자화율 측정결과 Neel temperature($T_N$)에 상응하는 8K 이하에서 superexchange를 통한 반자기성 magnetic coupling을 발견하였다. $T_N$이상의 온도에서는 Curie-Weiss법칙을 따른다. 자기 모멘트, C(Curie), 그리고 $\theta$(Weiss Constant)는 각각 2.77 B.M., 0.9593K, 그리고 -19.02K 이다. 측정 결과로부터 얻은 유효 자기 모멘트는 spin-only $Ni^{2+}d^8$(2.83 B.M.)계의 결과와 일치한다.