• Transactions on Electrical and Electronic Materials
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• 제18권6호
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• pp.364-369
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• 2017

Double molybdate $NaGd_{1-x}(MoO_4)_2:Ho^{3+}/Yb^{3+}$ phosphors with proper doping concentrations of $Ho^{3+}$ and $Yb^{3+}$ ($x=Ho^{3+}+Yb^{3+}$, $Ho^{3+}=0$ and 0.05, and $Yb^{3+}=0$, 0.35, 0.40, 0.45, and 0.50) were successfully synthesized using the microwave sol-gel method. Well-crystallized particles formed after heat-treatment at $800^{\circ}C$ for 16 h showed fine and homogeneous morphologies with particle sizes of $1{\sim}3{\mu}m$. The spectroscopic properties were examined using photoluminescence emission and Raman spectroscopy. Under excitation at 980 nm, the upconversion doped samples exhibited strong yellow emissions, from the combination of strong emission bands at 545 nm and 655 nm in the green and red spectral regions, respectively. The strong 545 nm emission band in the green region corresponded to the $^5S_2/^5F_4{\rightarrow}^5I_8$ transition in the $Ho^{3+}$ ions, while the strong 655 nm band in the red region appeared because of the $^5F_5{\rightarrow}^5I_8$ transition in the $Ho^{3+}$ ions. The pump power dependence and the Commission Internationale de L'Eclairage chromaticity of the upconversion emission intensity were evaluated in detail.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권6호
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• pp.471-476
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• 2006

Pseudomonas aeruginosa F722 produces a biosurfactant (BS) during its degradation of carbon and hydrocarbon compounds. The culture conditions for upgrading the biosurfactant productivity were investigated. The concentration of the biosurfactant produced by P. aeruginosa F722 was 0.78 g/L in C-medium; however, this increased to 1.66 g/L in BS medium, which was experimentally adjusted to optimal conditions. $NaNO_{2}$ was found to be most effective for microbial growth, with an $O.D_{600nm}$ of 1.18 for 0.1 % $NaNO_{2}$. Microbial growths, according to the $O.D_{600nm}$ were 2.53, 2.68, 2.89, and 2.87 for glucose, glycerol, $n-C_{10},\;and\;n-C_{22}$, respectively. Clear zone diameters (cm), indicating biosurfactant activity, were 9.0, 8.8, 5.7, and 8.5 for glucose, glycerol, $n-C_{10},\;and\;n-C_{22}$, respectively. Microbial growth was not consistent with the biosurfactant activity. The best biosurfactant activity was found with a C/N ratio of 20. Under optimal culture condition, the average surface tension decreased from 70 to 30 mN/m after 5 days. With aeration of 1.0 vvm, the biosurfactant produced increased to 1.94 g/L (up to 20%) compared to that of 1.66 g/L with no aeration. With aeration, the velocities of glucose degradation during both the log and stationary growth phases increased from 0.25 and $0.18\;h^{-1}$ to 0.33 and $0.29\;h^{-1}$, respectively, and the time for the culture to arrive at the maximum clear zone diameter became shorter, from 80 down to 60 h with no aeration.

• 디지털융복합연구
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• 제10권11호
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• pp.449-457
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• 2012

본 연구의 목적은 PET/CT 검사시 공간선량을 측정 비교함으로써 방사선 발생원과 종사자간 선량의 상관관계를 규명하고 효율적인 관리를 통해 피폭선량을 감소시키는데 있다. 최근 PET/CT 검사의 증가는 동위원소 사용량의 증가와 더불어 종사자의 피폭 증가의 원인이 되고 있다. 따라서 각 방사선 발생원에서의 공간선량을 비교 분석하고 개인방호복과 차폐체 사용에 관한 연구를 수행하였다. 양전자 방출핵종인 $^{18}F$ 방출 감마선 고에너지(511 keV)에서 개인방호복(0.5 mm pb) 사용은 미사용 시 보다 더 많은 피폭을 초래함을 확인하였다.

• 대한디지털의료영상학회논문지
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• 제14권2호
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• pp.75-81
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• 2012

The purpose of this study was administered to the body for examination and treatment, high-energy radioactive isotope(F-18, I-131) in vitro discharge experiments. Increasing exposed dose of radiation to health professionals is caused by the increase of PET/CT use and a radioactive isotope. Therefore, the high-energy isotope F-18 and I-131 after administration about using Metabolite excretion was studied. As a results of this study, patients had plenty of fluids for testing and treatment alone administered radiopharmaceuticals can be more than twice as fast excretion induced emissions. Also was able to get a better image space to reduce the dose rate.

• Journal of Microbiology and Biotechnology
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• 제18권12호
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• pp.1903-1907
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• 2008

Prodigiosin is a natural red pigment with algicidal activity against Cochlodinium polykrikoides, a major harmful red-tide microalga. To increase the yield of prodigiosin production by Hahella chejuensis KCTC 2396, significant medium components were determined using a two-level Plackett-Burman statistical design technique. Among 12 components included in basal medium, $NaHCO_3$, ${Na}_{2}{SiO}_{3}$, ${NH_4}{NO_3}$, ${Na}_{2}{SO}_{4}$ and $CaCl_2$ were determined to be important for prodigiosin production. The medium formulation was finally optimized using a Box-Behnken design as follows: 1% sucrose; 0.4% peptone; 0.1 % yeast extract; and (g/l): NaCl, 20.0; ${Na}_{2}{SO}_{4}$, 9.0; $CaCl_2$, 1.71; KCl, 0.4; and (mg/l): ${H_3}{BO_3}$, 10.0; KBr, 50.0; NaF, 2.0; $NaHCO_3$, 45.0; ${Na}_{2}{SiO}_{3}$, 4.5; ${NH_4}{NO_3}$, 4.5. The predicted maximum yield of prodigiosin in the optimized medium was 1.198 g/l by the Box-Behnken design, whereas the practical production was 1.495 g/l, which was three times higher than the basal medium (0.492 g/l).

• 대한화학회지
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• 제18권6호
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• pp.400-407
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• 1974

60몰%$AlCl_3$-40몰% NaCl의 용융염($453^{\circ}$<\TEX>K)속에든 알루미늄 전극에 대하여 전류-전압 편극곡선을 얻었다. 50mA/$CM^2$보다 큰 전류밀도에서는 옴-저항에 의한 전위차가 양극전위에 상당히 기여하므로 저항이 큰 $AlCl_3$(혹은 $AlCl_3$ 의 농도가 큰 멜트)의 층이 양극표면에 가까이 형성된다고 결론지었다. IR-전위차에 대하여 보정한 후의 Tafel곡선과 Allen-Hickling 곡선으로 부터 겉보기 transfer-coefficient, ${\alpha}_a$=(2.3RT/F)(dlogi/d${\eta}$)=$1.5{\pm}0.25$가 얻어졌다. 약 30mA/$cm^2$보다 큰 음극전류밀도에서는 느린 이온확산과 dendrite 생장 때문에 속도론적 측정이 방해 받았다.

• 동의생리병리학회지
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• 제25권2호
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• pp.345-351
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• 2011

This study was to examine the positive and negative affect related to psychological characteristics of each Sasang types using Positive and Negative Affect Schedule (PANAS) with 78 students from School of Korean Medicine, Pusan National University. After determining the Sasang types by QSCC II, the psychological characteristics of each Sasang types were analysed by PANAS. We did ANOVA analysis with eight related scales and found significant differences between the Tae-Eum type ($18.71{\pm}8.75$, $6.47{\pm}3.36$, $6.31{\pm}2.47$, $3.18{\pm}2.77$, $10.94{\pm}10.08$) and the So-Eum type ($13.38{\pm}6.03$, $4.55{\pm}2.23$, $4.19{\pm}2.16$, $5.81{\pm}4.20$, $1.83{\pm}9.17$, respectively) in Positive Affect (PA) (F=3.931, p=0.024), PA-Joy (F=3.991, p=0.023), PA-Interest (F=5.025, p=0.009), NA-Afraid (F=3.118, p=0.050), and Difference between Positive and Negative Affect (DPN) (F=6.355, p=0.003) scores. The post-hoc analysis showed that the Tae-Eum type ($18.71{\pm}8.75$, $6.47{\pm}3.36$, $6.31{\pm}2.47$, $10.94{\pm}10.08$) has significantly higher score than So-Eum type ($13.38{\pm}6.03$, $4.55{\pm}2.23$, $4.19{\pm}2.16$, $1.83{\pm}9.17$, respectively) in PA (p=0.018), PA-Joy (p=0.021), PA-Interest (p=0.017), and DPN (p=0.002) scores. The So-Eum type ($5.81{\pm}4.20$) showed significantly (p=0.047) higher score than the Tae-Eum type ($3.18{\pm}2.77$) in NA-Afraid. Results demonstrated distinct affect profile differences between Tae-Eum and So-Eum Sasang types using PANAS. This study may serve as the foundation in identifying psychological traits of Sasang types, especially regarding the aspect of affect.

• 대한소아치과학회지
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• 제36권1호
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• pp.38-45
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• 2009

본 연구는 상품화된 10% CPP-ACP 크림 (Tooth mousse, GC Co., Japan)이 0.05 % NaF 불소 용액 매일 양치법을 대체할 수 있는지 알아보기 위하여, 인공 탈회 병소를 가진 우치 법랑질에 대해 10일간 위 두 가지 방법 단독 혹은 복합 사용의 재광화 효과를 비교하였다. 0.1% thymol 용액에 냉장 보관한 소의 치아를 교정용 레진 (Orthodotic resin, Dentsply international Inc., USA)에매몰한 후 탈회 용액에 96시간 보관하였고, 총 60개의 시편을 5개의 군으로 나누었다; 비처치군 (1군), 0.05% NaF 용액 1분 (2군), Tooth mousse 3분 (3군), 0.05% NaF 용액 1분 처리 후 Tooth mousse 3분 (4군), Tooth mousse 3분 처리 후 0.05% NaF 용액 1분(5군). 재광화 정도는 10일간의 시편 처리 전 후의 Vickers hardness number를 측정하여 비교하였으며, 연구 결과는 다음과 같다. 1. 각 군에서 시편 처리 전후의 표면경도를 paired t-test를 이용하여 비교분석한 결과, 3, 4, 5 군에서만 유의할만한 표면 경도 증가가 나타났다(P < 0.05). 2. 각 군별로 평균 표면 경도 증가량은 5 > 4 > 3 > 2 > 1 군 순이었고, 각 군의 표면경도 증가량을 one-way ANOVA test로 비교분석한 후 Duncan test로 사후 검정한 결과, 4, 5 군은 1, 2, 3 군과 유의할만한 표면경도 증가를 보였으며 (P < 0.05), 다른 군들 간에는 유의할만한 차이를 보이지 않았다. 3. Tooth mousse를 우치에 10일간 적용시킨 결과 0.05% NaF 용액보다 더 많은 표면경도 변화량을 나타냈지만, 통계학적으로 유의할만한 차이는 없었다. 이상의 결과에서 Tooth mousse 사용은 불소 양치가 용이하지 않은 환자들에게 양호한 대체 방안이 될 것으로 사료되며, 또한 불소 적용시 Tooth mousse를 복합 사용하는 것이 추천될 수 있으리라 사료된다.

• Applied Biological Chemistry
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• 제13권1호
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• pp.59-64
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• 1970

Bence Jones 단백질(蛋白質)(As,Ik,In)를 DEAE-Sephadex A-50 Column으로 0.02M phosphate Buffer(pH8.)와 0.5M NaCl를 gradient로 사용(使用)해 정재(精製)하였다. 시료(試料) As(K-형(型))의 정재결과(精製結果) 주성분(主成分)인 F-1는 조단백질(粗蛋白質) 500mg로부터 350mg 얻었으며 다른 시료(試料) Im와 Ik($lambda$-형(型))에서도 각각 주성분(主成分)을 242mg(Im)와 146mg(Ik) 얻을 수 있었다. 정재(精製)한 시료(試料)는 그의 순도(純度)를 알기 위해 Poly acryl amide의 Disc electrophoresis로 확인한 후 K-형(型) Bence jones단백질(蛋白質)의 일종(一種)인 As와 $lambda$-형(型)의 일종(一種)인 IM를 6N-HCI로 $105^{\circ}C$에서 20시간(時間) 가수분해(加水分努)후 Amino 산(酸) 조정(組成)을 살펴보았다. DNP법(法)으로 시료(試料) K-형(型)(As, Ko, Ta)의 단백질(蛋白質)의 N-말단(末端)을 검출(檢出)해 Ta는 glutamic acid, Ko, As는 Aspartic acid임을 확인하였으며 Paper 상(上)에 나타난 DNP-Amino 산(酸)은 5% $NaHCO_3$ (pH8) 4ml에 추출(抽出)해 그 수량(收量)을 ${\varepsilon}=18.1{\times}10^3DNP$ $Asp\;{\varepsilon}=17.41{\times}10^(3){\;}DNP{\;}Glu$에 의(依)해 산출(算出)하였더니 Ko는 54.3%, As는 65%이였으며 Ta는 85%의 수량(收量)이였다. ${\lambda}$-형(型)의 Im,Ik의 시료(試料)도 DNP법(法)으로 N-말단(末端)을 검출(檢出)해 보았더니 검출(檢出)되지 아니하였다.

• 대한방사성의약품학회지
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• 제3권2호
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• pp.116-121
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• 2017

To overcome the low reactivity and solubility of alkali metal fluorides (MFs), various types of phase transfer catalysts (PTCs) have been developed over the last decades. However, since the fluoride activated by such PTC sometimes has a strong basicity, it may cause various side reactions such as elimination reaction or hydroxylation reaction in the nucleophilic fluorination reaction. Also, they may cause separation problems in the compound purification process. In recent advanced study, various PTCs have been developed to solve these problem of conventional catalyst. In this review, we would like to introduce three kinds of novel multifunctional organic catalysts such as bis-tert-alcohol-functionalized crown-6-calix[4]arene (BACCA), easy separable pyrene-tagged ionic liquid (PIL) by reduced graphene oxide (rGO), and tri-tert-butanolamine organic catalyst.