• Proceedings of the Korea Water Resources Association Conference
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• 1982.07a
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• pp.3-24
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• 1982

The relations between tidal fluctuation and freshwater discharge are stuied dy use of observed data in the estuarine region of the Nagdong Rivre. Damping modulus which represents the resistance to propagation of tidal wave is estimated, and it is verified that when the fresh water discharge is lower than 300 m/sec., the elevation of mean-water-level at Gupo is the same as mean sea-water-level.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.232-233
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• 2002

Nanostructed high energy Nd-Fe-B based bulk magnet can be prepared by hot-working process (hot press and die-upset) from melt-spun amorphous or nanocrystalline powder.[1] Recently, we have investigated a modified method, current-applied pressure-assisted (CAPA) process, to produce nanocrystalline isotropic and anisotropic NdFeB magnets. The process consists of current-applied pressing the melt-spun powders to obtain isotropic precursor subsequent current-applied deforming the precursor to obtain textured magnet.[2-3] (omitted)

• Journal of the Korean Magnetics Society
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• v.3 no.2
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• pp.143-148
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• 1993

$Bi_{x}Dy_{3-x}Al_{1}Fe_{4}O_{12}$(x=1, 1.2, 1.5) magnetic garnet films were fabricated on the glass substrates by pyrolysis method. As the Bi content was increased, the saturation magnetization increased from 5 emu/cc to 11 emu/cc and all the films showed perpendicular magnetic anisotropy. As the content of Bi was increased, Faraday rotation angle (${\theta}_F$) at 780 nm of the films increased from $0.11^{\circ}/\mu\textrm{m}$ to $0.20^{\circ}/\mu\textrm{m}$ and the garnet crystallization temperature decreased from $660^{\circ}C$ to $630^{\circ}C$. Also, the coercivity ($H_{c}$) decreased from 1200 Oe to 600 Oe and the grain sizes increased. $H_{c}$ decreased from 1750 Oe to 1200 Oe and ${\theta}_F$ increased due to the interference of the reflected laser light as the thickness of the films increased from $2000\;{\AA}$ to $4000\;{\AA}$.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.181-181
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• 2013

최근에 형광체 결정 입자의 크기와 적당한 활성제 이온의 종류를 선택하여 우수한 발광 특성을 갖는 세라믹 형광체를 합성하고자 많은 노력을 경주하고 있다. 본 연구에서는 비교적 간단한 장비로 구성되며, 볼밀을 통하여 초기 물질들을 혼합하고 분쇄하여 최적의 형광 특성을 갖는 형광체 분말을 비교적 용이하게 합성하기에 적합한 고상반응법을 사용하여 적색, 황색, 녹색 형광체 La2WO6:RE3+ (RE=Eu, Dy, Tb)를 제조하고자 한다. 사용한 초기 물질은 (99.99% 순도), (99.99%), (99.9%), (99.9%) (99.9%)을 화학 정량으로 준비하였고, 활성제 이온의 함량비를 0, 0.01, 0.05, 0.10, 0.20 mol로 각각 변화시켜 형광체를 제조하여 그것의 발광과 흡광, 결정 입자의 크기와 형상을 조사하였다. 이온이 도핑된 형광체의 경우에, 발광 스펙트럼은 이온의 함량비에 관계없이 모든 시료에서 전형적인 이온의 (j=1-4) 전이에 의한 발광 스펙트럼을 나타내었고, 가장 강한 적색 발광 파장은 611 nm에서 관측되었으며, 이온의 함량비가 0.15 mol에서 발광 피크가 장파장 쪽으로 10 nm 이동하였으며, 세 종류의 발광 스펙트럼의 세기는 최대를 나타내었다. 이온의 함량비가 더욱 증가함에 따라 모든 발광 스펙트럼의 세기는 순차적으로 감소하였다. 이 현상은 농도 소광 현상으로 해석 할 수 있다. 이온이 도핑된 형광체의 경우에, 이온의 함량비에 관계없이 모든 시료에서 이온의 전형적인 전이에 의한 발광 스펙트럼이 관측되었으며, j=13/2에서 가장 강한 황색 발광이 피크 581 nm에서 관측 되었다. 상대적으로 발광 세기가 약한 484 nm에 정점을 갖는 청색 발광스펙트럼은 전이 신호이다. 이온의 함량비가 0.10 mol 일 때 세 영역의 발광 스펙트럼의 세기는 최대를 나타내었다. 이온의 함량비가 증가함에 따라 모든 발광 스펙트럼의 세기는 순차적으로 감소하였다. 주 흡광 스펙트럼은 이온의 함량비에 관계없이 모든 시료에서 파장 250 nm에서 관측되었다. 이온이 도핑된 형광체의 경우에, 이온의 함량비에 관계없이 모든 형광체 분말은 발광 세기가 제일 강한 550 nm의 피크를 갖는 녹색 발광과 상대적으로 발광 세기가 약한 495와 590 nm에 피크를 갖는 청색과 주황색 발광 스펙트럼들이 각각 관측되었다. 이 발광 신호들은 Tb3+ 이온의 5D47Fj (j=4, 5, 6) 전이에 의해 발광된 신호임을 확인하였다.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.1
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• pp.187-192
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• 2006

Herbal medicines have been utilized to treat a variety of diseases, including cancer. Several species of the family rubiaceae have been reported to have antitumor activity. In this study, we report the cytotoxicity and antitumor activity exhibited dy the methanol extracts prepared from Rubia radix (RRME), Uncaria gambir (UGME) and Oldenlandia diffusa (ODME) (family: Rubiaceae) against human promyleloid leukemia cell line, HL-60. The cytotoxicity of RRME (2~20 ${\mu}g/ml$), UGME (20~200 ${\mu}g/ml$) and ODME (20~200 ${\mu}g/ml$) were assessed dy the MTT reduction assay. IC50 values for RRME, UGME and ODME were 11.0, 99.5 and 106.1 ${\mu}g/ml$, respectively. When the HL-60 cells were treated with RRME (10 ${\mu}g/ml$), UGME (120 ${\mu}g/ml$) and ODME (140 ${\mu}g/ml$) for 24 h, several apoptotic characteristics such as DNA fragmentation and morphologic changes were observed. Furthermore, flow cytometric analysis was peformed to determine the percent of apoptotic cells. The poupulation of sub-G1 hypodiploid cells was increased 37.49% in RRME treatment, 12.49% in UGME treatment and 7.21% in ODME treatment compared with untreated control cells (2.64%). To further confirm apoptotic cell death, we assayed caspase-3, -8 and -9 activities in RRME, UGME and ODME-treated cells. After treatment of RRME, UGME and ODME for 12 h, caspase-3, -8 and -9 activities significantly increased.compared to untreated control cells. These results show that RRME, UGME and ODME induced apoptotic cell death in HL-60 cells and may have a possibility of potential antitumor activities.

• Journal of the Korean Ceramic Society
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• v.50 no.1
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• pp.50-56
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• 2013

Phosphorescent materials coated with titanium dioxide were fabricated and photocatalytic reactions between these materials and VOCs gases were examined. A thin film (approx. 100 nm) of nanosized $TiO_2$ was deposited on the $Sr_4Al_{14}O_{25}$ : $Eu^{2+}$, $Dy^{3+}$, $Ag^+$ phosphor using low-pressure chemical vapor deposition (LPCVD). The characteristics of the photocatalytic reaction were examined in terms of the decomposition of benzene gas using a gas chromatography (GC) system under ultraviolet (${\lambda}$ = 365 nm) and visible light (${\lambda}$ > 420 nm) irradiation. $TiO_2$-coated $Sr_4Al_{14}O_{25}$ : $Eu^{2+}$, $Dy^{3+}$, $Ag^+$ phosphor showed different photocatalytic behavior compared with pure $TiO_2$. $TiO_2$-coated phosphorescent materials showed a much faster photocatalytic decomposition of benzene gas under visible irradiation compared to the pure $TiO_2$ for which the result was practically negligible. This suggests that the extension of the absorption wavelength to visible light occurred through energy band bending by a heterojunction at the interface of the $Sr_4Al_{14}O_{25}-TiO_2$ composite. Also, the $Sr_4Al_{14}O_{25}-TiO_2$ composite showed the photocatalytic decomposition of benzene in darkness due to the photon light emitted from the $Sr_4Al_{14}O_{25}$ phosphors.

• Journal of the Korean Society of Clothing and Textiles
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• v.38 no.3
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• pp.404-414
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• 2014

This study investigates the dyeability and fastness of jacquard fabric for blind using low-melting flame retardant polyester. Two types of jacquard fabric were prepared with a low-melting flame retardant polyester and regular polyester. The low-melting flame retardant polyester has a sheath and a core. The core consists of flame retardant polyester and the sheath consists of low-melting polyester. Disperse red 50 (DR 50), disperse blue 56 (DB 56), disperse yellow (DY 54) of E-type dyes and disperse 92 (DR 92), disperse blue 60 (DB 60), disperse yellow (DY 79) of S-type dyes were used and dyed on jacquard fabrics dependent of dyeing temperature and time. The fastness, dye exhaustion, color strength (K/S value), and colorimetric properties of jacquard fabrics were evaluated. The dyeability of S-type dyes were higher than E-type dyes. The experiments indicated optimum dyeability that the dyeing temperature was $110^{\circ}C$ for E-type dyes and $120^{\circ}C$ for S-type dyes for 40 minutes. The fastness to washing and light were excellent at a 4-5 grade.

• Applied Biological Chemistry
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• v.28 no.2
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• pp.98-105
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• 1985

In the sheep and cattle's rumen, facultative anaerobic cellulolytic bacteria were isolated by using Hungate's roll tube technique. In the 21 isolated species, one was screened by its strong cellulolytic activity and identified as Cellulomonas fimi C-14 by investigate morphological, cultural, physiological characteristics and electron microgram. Optimum conditions of the cell growth and enzyme production were pH 6.5 an $30^{\circ}C$, Thiamine and biotin support a good growth of C. fimi C-14. In the enzyme activities, Crystalline cellulose hydrolyzing activity, CMCase activity and ${\beta}-glucosidase$ activity were 20.6, 226.6 and 0.56$(unit{\times}10^3/ml)$ at pH 6.0, $40^{\circ}C$. By addition of fungal cellulase, enzyme activity was increased. Simultaneous Saccharification Fermentation is better than two step fermentation in ethanol yield with Saccharomyces cerevisiae DY2.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.1
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• pp.115-124
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• 2006

The purpose of this study is to investigate the relationships between the biological base of coping strategy and the different constitutions. First of all, subjects were divided in to 3 groups dy Questionnaire for the Sasang Constitution Classification II and Yin-Yang Property Analysis. Then each group was assigned into two experimental coping conditions, active and passive condition, in turn. The SDNN(The Standard Deviation of the NN Intervals) of HRV(Heart rate variability) index was estimated from two conditions after giving a aversive pain stimulus. The results of the study were as follows 1. The interaction between constitution and coping condition is significant(p<0.05). 2. The SDNNs of Shaoyangren are higher than those of Taiyinren under passive condition but it was opposite under active condition(p<0.05). 3. The main effect of constitution is also significant but that of coping condition is not significant. 4. Thee Shaoyangren is higher than Shaoyinren in multiple comparisons(p<0.05). 5. The interaction between Yin-Yang constitution and coping condition is significant and the main effect of only constitution is significant(p<0.05). According to these results, different constitution can respond differently to coping condition and It is highly related to biological mechanism associated with two basic coping strategies.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.1
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• pp.149-155
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• 2006

To prevent human body injury from oxidative stress, antioxidants are very important and many research about antioxidants are generally being conducted. Hydrogen peroxide($H_2O_2$) that is one of vitality oxygen species has been seen that cause various diseases, DNA damage and gene change. The purpose of this study was to examine the inhibition effect of Zizania latifolia Rhizoma on apoptosis induced by $H_2O_2$ in Neuro2A cell. Neuro2A cells were cultivated in RPMI(GibcoBRL) with 5% FBS and treated with $H_2O_2$ and Zizania latifolia Rhizoma. We measured the cell viability and analyzed DNA fragmentation. Activity of PARP, Cytochrome C, caspase-9, caspase-3, p53, p21, Bax and Bcl-2 in the cell was examined dy using western blot. The results obtained were as Follows: The cell viability in Zizania latifolia Rhizoma treatment (60ug/ml<) decreased significantly compared with that of none treatment. (P<0.001) Zizania latifolia Rhizoma increased cell viability about twice as much as that being injury by $H_2O_2$. (Zizania Latifolia Rhizoma 20ug/ml, $H_2O_2$ 200uM, P<0.001) DNA fragmentation developed by $H_2O_2$, but was not developed in Zizania latifolia Rhizoma treatment. PARP, Cytochrome C, caspase-9 and caspase-3 activated all by $H_2O_2$ but were not activated in Zizania latifolia Rhizoma treatment. P53, P2l and Bax activated dy $H_2O_2$, and Bcl-2 got into inactivation. But the opposite results appeared in Zizania latifolia Rhizoma treatment. In conclusion, these results suggest that Zizania latifolia Rhizoma inhibit the development of DNA fragmentation and apoptosis by $H_2O_2$ and the antioxidant action of Zizania latifolia Rhizoma is effective. More researches about effect of Zizania latifolia Rhizoma are considered to need.