• KSBB Journal
• /
• v.28 no.4
• /
• pp.244-248
• /
• 2013

In order to investigate functional characterization of callus extracts of apple 'Hirosaki' for cosmetic materials, biological activities of its extracts including wrinkle improvement, hair growth, and anti-inflammatory effect were investigated. The callus extract showed similar activity with TGF-${\beta}$ used as positive control at 50 ${\mu}g/mL$ in the test of collagen synthesis, and increased 40% of proliferation of hair follicle dermal papilla cells. Especially, in case of anti-inflammatory effect, callus extract inhibited about 50% of COX-2 expression which was known as response for intermediating inflammation, and about 70% of eotaxin-1 production which was increased by atopy dermatitis.

• Journal of the Korean Ceramic Society
• /
• v.41 no.11
• /
• pp.793-796
• /
• 2004

Process Parameters were studied in synthesis of LiCoO$_2$ Powder by ultrasonic spray Pyrolysis. Concentration of the mixed solution influenced the size, shape, and yield of the synthesized powder. The yield was affected primarily by the height of the solution, and then by the flow rate of a carrier gas. The temperature of the reactor governed the crystallinity and morphology of the powder. LiCoO$_2$ powders were synthesized as a layered high temperature phase above 800$^{\circ}C$. The synthesized powders were sphere and secondary Particles consisted of primary particles of 55-70 nm. The secondary Particles became bigger from 0.28 to 1.43 $\mu\textrm{m}$ as the concentration of the solution was increased from 0.05 to 2.0 M. The 2.0 M solution provided the highest production rate.

• Archives of Pharmacal Research
• /
• v.25 no.5
• /
• pp.590-599
• /
• 2002

Eight rigid compounds designed as esterase-stable analogues of methyl 2,5-dihydroxycinnamate (1) were synthesized. These derivatives include 2-(2',5'-dihydroxybenzylidene)cyclopentenone (3a), 2-(2',5'-dihydroxybenzylidene)cyclohexanone (3b), 2,6-bis(2',5'-dihydroxybenzy-lidene)cyclohexanone (4b), 2,6-bis(2',5'-dihydroxybenzylidene)cyclopentenone (4a), (E)-3-(2',5'-dihydroxybenzylidene)pyrrolidin-2-one (5), (E)-5-(2',5'-dihydroxybenzylidene )-1,2-isothiazolidine-1,1-dioxide (6), 4-(2',5'-dihydroxyphenyl)-5H-furan-2-one (7), and 3-(2',5'-dihydroxyphenyl)cyclopent-2-ene-1-one (8). Among the eight compounds, the furanone 7 and cyclopentenone 8 showed the most potent cytotoxicity with $IC_{50}$ values of 0.39-0.98 $\mu\textrm{g}$/mL. Compound 8 was further brominated, phenylated and methylated at the a position to give three corresponding analogues, including 2-bromo-3-(2',5'-dihydroxyphenyl)cyclopent-2-ene-1-one (24), 3-(2',5'-dihydroxyphenyl)-2-phenylcyclopent-2-ene-1-one (27), and 3-(2',5'-dihydroxyphenyl)-2-methylcyclopent-2-ene-1-one (28). Among the three, the most enhanced activity was observed with the phenylated compound 27.

• Korean Journal of Materials Research
• /
• v.13 no.4
• /
• pp.219-223
• /
• 2003

Zirconia gels dispersed with fine Au particles have been prepared by the sol-gel method. Starting solution with (OC$Zr_4$$H_{ 9}$)$_4$, $C_4$ $H_{9}$ OH, $H_2$O,$ HNO_3$, $HAuC1_4$ was used to prepare gels in several molar ratio. After hydrolysis, viscosity of solutions as 4∼5 cP and gelling time of sols were spent about 9 days. As the heat-treatment temperature was increased,$ ZrO_2$ had the phase transition from tetragonal to monoclinic at $750^{\circ}C$. Heat-treatments of the gel have performed at 500, 700, 750, 800, 1000 and $1100^{\circ}C$ for 3 hrs, respectively. We have investigated TG-DTA, X-ray diffraction patterns, SEM and EDS. The size of Au fine particles dispersed in the heat-treatmented gel was about 0.15∼0.23 $\mu\textrm{m}$ and the shape was most sphericity.

• Korean Journal of Materials Research
• /
• v.8 no.6
• /
• pp.551-559
• /
• 1998

장경비가 큰 탄화규소를 탄소와 규소간의 고온연소반응으로 제조하기 위하여 공정변수에 따른 연소거동과 미세조직의 변화를 조사하였다. 연소합성된 생성물은 주로 $\beta$-SiC이며 연소반응이 충분히 진행되지 못하였을 경우에는 미량의 잔류 반응물과 $\alpha$-SiC가 관찰되었다. 생성된 탄화규소의 평균입도는 약 5$\mu\textrm{m}$로 작았으며, $1300^{\circ}C$ 이상의 예열 조건에서 장경비가 30이상인 탄화규소를 합성할 수 있었다. 압분 강도가 69MPa인 분말의 성형체에서 평균 연소 온도와 평균 전파 속도는 각각 약 $1425^{\circ}C$와 2.1mm/sec 범위이며, 연소 온도는 흑연 분말을 사용하였을 경우가 탄소 섬유를 사용한 경우보다 약 $10^{\circ}C$ 높았다. 연소 반응을 임의로 중단시킨 시편의 계면을 EDX와 Auger 전자 현미경으로 분석한 결과 상호 확산층이 관찰되지 않았다. 이는 탄화규조의 연소합성이 용해-석출 모델에 의하여 진행됨을 시사한다. 예열 온도에 따른 연소 반응 중의 온도 분포를 유한 요소법으로 해석함으로써 $2500^{\circ}C$의 초기 연소 개시 온도에 대하여 예열 온도 $300^{\circ}C$에서는 연소파가 거의 전파할 수 없으며 예열 온도가 $1300^{\circ}C$에서는 시료 내부에 자체 전파가 가능한 $2000^{\circ}C$이상의 온도 구역이 존재함을 알았다.

• Korean Journal of Materials Research
• /
• v.26 no.7
• /
• pp.363-369
• /
• 2016

$NaCaLa_{1-x}(MoO_4)_3:Ho^{3+}/Yb^{3+}$ ternary molybdates with proper doping concentrations of $Ho^{3+}$ and $Yb^{3+}$ (x = $Ho^{3+}+Yb^{3+}$, $Ho^{3+}$ = 0.05 and $Yb^{3+}$ = 0.35, 0.40, 0.45 and 0.50) were successfully synthesized by microwave sol-gel method. Well-crystallized particles formed after heat-treatment at $900^{\circ}C$ for 16 h showed a fine and homogeneous morphology with particle sizes of $3-5{\mu}m$. Under excitation at 980 nm, the UC intensities of the doped samples exhibited strong yellow emissions based on the combination of strong emission bands at 520-nm and 630-nm emission bands in the green and red spectral regions, respectively. The optimal $Yb^{3+}:Ho{3+}$ ratios were obtained at 9:1 and 10:1, as indicated by the composition-dependent quenching effect of the $Ho^{3+}$ ions. The pump power dependence of the upconversion emission intensity and the Commission Internationale de L'Eclairage chromaticity coordinates of the phosphors were evaluated in detail.

• Journal of Veterinary Clinics
• /
• v.17 no.2
• /
• pp.305-314
• /
• 2000

Recombinant inteileukin-2 (IL-2) is a potent inductive stimulus for nitric oxide synthesis (NO.) and has been demonstrated as an antineoplastic agent in mice and human. But it is not let clear whether NO. can contribute to IL-2-induced therapeutic responses. Therefore, the current experiment was undertaken to clarify the effect of IL-2 on antitumor response against subcutaneous Meth-A tumor in mice. At the beginning of each experiment, normal BALB/c mice were injected subcuta-neously with $5{\times}10^6 Meth-A$ tumor cells. Some mice were implanted with osmotic minipumps con- taining 225 $\mu$l of 3.38 M $N^{\gamma}$ -monomethyl-L-arginine (MLA. an NOS inhibitor). Beginning on day 7, experimental groups were treated with a f-day course of IL-2 (50,000 lU,75,000 nJ,100,0007, 50,000 IU+MLA, 75,000 IU+MLA, 100,000 IU+MLA intraperitoneal injection every 12 hours for 5 days). The result of this experiment revealed that Meth-A tumor grew progressively in control mice. Intraperitoneal IL-2 treatment decreased tumor growth and prolonged survival. compared with con-trol mice. But no significant differences among 50.000 lU.75.000 lU and 100,000 lU of 7-2 treat-ment were observed. MLA administration prevented partially the decrease tumor growth and prolong survival of IL-2 treated mice compared with mice receiving IL-2 alone.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09b
• /
• pp.1114-1115
• /
• 2006

The preparation of single-phase $CuLaO_2$ with delafossite-type structure by means of the solid-state reaction method was investigated using X-ray diffraction. The results showed that notwhistanding the fact that there was a trace of metallic copper, nearly single-phase $CuLaO_2$ was obtained by using $La(OH)_3$ as a lanthanum source and by firing the mixed powder with nonstoichiometric composition ratio of $La(OH)_3:Cu_2O=1:1.425$ in a vacuum at 1273 K for 10 h. The measurement of electrical conductivity and Seebeck coefficient showed that $CuLaO_2$ thus obtained was a p-type semiconductor and had a Seebeck coefficient of approximately $70{\mu}V/K$.

• Journal of Microbiology and Biotechnology
• /
• v.28 no.6
• /
• pp.902-908
• /
• 2018

Optimization of the culture medium to maximize menaquinone-7 (MK-7) production by Bacillus subtilis strain KCTC 12392BP in static culture was carried out using statistical experimental methods, including one factor at a time, fractional factorial design, and response surface methodology (RSM). Maltose (carbon source), tryptone (nitrogen source), and glycerol (activator) were identified as the key medium components for MK-7 synthesis by the fractional factorial design, and were selected for statistical optimization by RSM. The statistical analysis indicated that, in the range that was studied, maltose, tryptone, and glycerol were all critical factors having profound effects on the production of MK-7, with their coefficients for linear and quadratic all significant at the p < 0.05 level. The established model was efficient and feasible, with a determination coefficient ($R^2$) of 0.9419. The predicted concentrations of maltose, tryptone, and glycerol in the optimal medium were determined as 36.78, 62.76, and 58.90 g/l, respectively. In this optimized medium, the maximum yield of MK-7 reached a remarkably high level of $71.95{\pm}1.00{\mu}g/ml$ after 9 days of static fermentation, which further verified the practicability of this optimized strategy.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2016.11a
• /
• pp.201.2-201.2
• /
• 2016

$Mg_xNi_yZn_{1-x-y}Fe_2O_4$ ferrite powders were prepared by self-propagating high temperature synthesis followed by classified by ultrasonic wet-magnetic separation method to get nano-sized particles with high purity. The $Mg_xNi_yZn_{1-x-y}Fe_2O_4$ ferrites were well formed by using several powders like iron, nickel oxide, zinc oxide and magnesium oxide at 0.1 MPa of oxygen pressure. The ultrasonic wet-magnetic separation of pre-mechanical milled ferrite powders produced the powders with average size of $3.7-0.8{\mu}m$. The addition of a surfactant during the separation process improved productivity more than twice. The coercive force, maximum magnetization and residual magnetization of the $Mg_xNi_yZn_{1-x-y}Fe_2O_4$ nano-powders with 810 nm size were 45.89 Oe, 53.92 emu/gOe, 0.4 emu/Oe, respectively.