• 생명과학회지
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• 제12권1호
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• pp.67-76
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• 2002

Agrobacterium(LBA4404/pBI1121)을 이용하여 형질전환된 애기장대 (Arabidopsis thaliana)를 대상으로 T2, T3, F3세대에서의 도입된 외래 유전자의 비활성화 현상을 조사하였다. Kanamaycin저항성 개체들의 GUS유전자 발현을 분석한 결과, T2세대에서 조사된 12계통 중 5계통에서 GUS 비활성 개체가 관찰되었다 (GUS유전자 비활성율 2.3%). Multi copy T-DNA 계통을 조사한 결과, GUS 비활성 정도가 더욱 심해짐이 관찰되었다 (5.8%). T3 세대에서 single copy T-DNA 계통들은 1.3%의 GUS 비활성율을 보인 반면, multi-copy T-DNA 계통에서의 비활성율은 12.6%로 급격히 증가하였다. 유사한 현상이 형질전환 식물체와 정상개체를 교배하여 생산된 F2 계통에서도 관찰되었다 (비활성율 9.9%). 본 실험으로 식물체에 도입된 외래 유전자가 후대에서의 전이과정동안 점진적으로 비활성화되고, 이 현상은 multi copy T-DNA 계통에서 훨씬 심각함이 밝혀졌다.

• KIEE International Transactions on Electrophysics and Applications
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• 제3C권3호
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• pp.106-112
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• 2003

A combined discharge type ozonizer was designed and manufactured. The increase or decrease of temperature greatly influences the characteristics of ozone concentration ( $O_{3con}$), ozone generation ( $O_{3g}$) and ozone yield ( $O_{3Y}$) of a discharge type ozonizer. The characteristics of ozone concentration, ozone generation and ozone yield rate were investigated by varying the gas flow rate (Q), the discharge power ( $W_{d}$) and the temperature (T). At T=25[$^{\circ}C$] the values of $O_{3con}$ were found as 5632, 4200, 2500 and l800[ppm] at Q = 1, 2, 4 and 6[l/min] respectively. At the same temperature the corresponding values of $O_{3g}$ were found as 662, 988, 1176 and l270[mg/h] and those of $O_{3Y}$ were found as 67, 102, 119 and 135[g/kWh] respectively. When the temperature is decreased to -50[$^{\circ}C$], the values of $O_{3con}$ were found as 9000, 6700, 4000 and 2800[ppm] respectively at Q = 1, 2, 4 and 6[l/min]. At the same value of temperature the corresponding values of $O_{3g}$ were found as 1220, 1576, 1882 and 2050[mg/h] and those of $O_{3Y}$ were found as 120, 159, 188 and 202[g/kWh] respectively. Hence as the temperature was decreased from 25 to -50[$^{\circ}C$], the efficiencies of ozone generation were increased by 79, 55, 58 and 49[%] respectively at Q = 1, 2, 4 and 6[l/min].]. 6[l/min].].

• 한국자기학회지
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• 제17권4호
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• pp.178-181
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• 2007

반도체의 고 집적회로를 형성하기 위하여 주로 이용하고 있는 광 리소그래피 기술을 대신하여 사용할 수 있는 차세대 리소그래피 기술로 전자빔 리소그래피 기술에 대한 연구가 진행되고 있다. 본 연구에서는 초소형 전자칼럼을 이용하여 전자빔 에너지와 조사농도에 따른 pattern 두께의 의존성을 조사하였으며 두께가 100nm인 $SiO_2$ 박막의 patterning을 통하여 $SiO_2$ 박막에 대한 저 에너지 전자빔 리소그래피 공정의 가능성을 입증하였다.

• KIEE International Transactions on Electrophysics and Applications
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• 제12C권4호
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• pp.201-207
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• 2002

A Pin-Cylinder discharge type ozonizer was designed and manufactured. The increase or decrease of temperature greatly influences on the characteristics of ozone generation of a discharge type ozonizer. The characteristics of ozone concentration ( $O_{3con}$), ozone generation ($_{3g}$) and ozone yield .ate ($_{3Y}$) of the ozonizer were investigated by varying the gas flow rate (Q), the discharge power ($_{Wd}$ ) and the temperature (T). At T = 20($^{\circ}C$), the values of ( $O_{3con}$) were found as 7800,5300,3000 and 2300(ppm) at Q=1,2,4 and 6(1/min) respectively. The corresponding values of ( $O_{3g}$) were found as 917, l247,1411 and 1623(mg/h) and those of ( $O_{3Y}$) were 93,126,143 and 164(g/kWh) respectively. When the temperature is decreased to -50($^{\circ}C$), the values of ( $O_{3con}$) became 12000,8000,5200 and 3600(ppm) at Q=1,2,4 and 6(1/min) respectively. The corresponding values of 0,9 were obtained as 1411,1882,2446 and 2600(mg/h) and those of ($O_{3Y}$) were 143,190,247 and 2631g/kWh] respectively. Hence as the temperature was decreased from 20 to -50[。C], the efficiencies of ozone generation were increased by 54,51,73 and 60[%] at Q=1,2,4 and 6(1/min) respectively.ctively.

• 전자공학회논문지A
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• 제29A권7호
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• pp.56-63
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• 1992

A measurement technique of the surface generation velocity S$_o$ using the BC(buried channel) MOS structure with shallow and low doped channel layer (BC MOS S$_o$ measurement technique) is presented and verified analytically and experimentally. Using this measurement technique, S$_o$ can be measured more accurately than that measured using the gate-controlled diode SS1oT measurement technique. When S$_o$ is measured for the two techniques from a BC MOS structure test patten with gate length of 171$\mu$m, the results are 0,66cm/sec and 0.28cm/sec for the former and the latter respectively.

• 한국안전학회지
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• 제9권2호
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• pp.12-17
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• 1994

Smoke evolved from burning cellulose insulation treated with boric acid-borax-alum as combustion retardants has been studied using a light absorption method. It has been shown that the quantity of smoke are decreased with the increase of oxygen concentration. Applied fire retardants did not increase smoke generation from investigated cellulose insulation in range of themal degradation without flaming. These same fire retardants increased from in the range of flaming combustion. The results of this work have been analysed using imperical equation, which correlated the smoke density at oxygen content of combustion transition. This equation may be. $\sigma$=$\sigma$$_{T}$ exp｛-7.24$\times$10$^{-7}$ ( $O_2$ $O_{2.T}$)｝Where $O_2$is the concentration of oxygen in the oxidizing gas, and $O_{2.T}$ refers to oxygen concentration of combustion transition.n.n.n.

• Biomolecules & Therapeutics
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• 제27권4호
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• pp.381-385
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• 2019

We attempted to examine anti-inflammatory and anti-oxidant effects of 4'-O-${\beta}$-D-glucosyl-5-O-methylvisamminol (GOMV), the first epigenetic inhibitor of histone phosphorylation at Ser10. While GOMV did not affect the viability of murine macrophage RAW 264.7 cells, it significantly suppressed lipopolysaccharide (LPS)-induced generation of prostaglandin $E_2$ ($PGE_2$) and nitric oxide (NO) through transcriptional inhibition of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). GOMV also scavenged free radicals in vitro, increased NF-E2-related factor 2 (NRF2), and activated antioxidant response element (ARE), thereby resulting in the induction of phase II cytoprotective enzymes in human keratinocyte HaCaT cells. Finally, GOMV significantly protected HaCaT cells against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced oxidative intracellular damages. Together, our results illustrate that GOMV possesses anti-inflammatory and anti-oxidant activity.

• 마이크로전자및패키징학회지
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• 제15권4호
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• pp.93-100
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• 2008

고온 발전용 열전모듈을 p-type으로는 $Ca_{2.7}Bi_{0.3}Co_4O_9$, n-type으로는 $Ca_{0.96}Bi_{0.04}Mn_{0.96}Nb_{0.04}O_3$을 선택하고 알루미나 기판 위에 1쌍과 2쌍을 제조하였다. 산화물 열전 모듈의 최적화 설계를 위해 먼저 1쌍의 열전모듈의 실험 결과로부터 전극의 접촉저항을 산출하여 2쌍 모듈에 적용함으로써 저항과 출력 특성을 예측하였다. 예측된 2쌍 모듈의 계산 값과 제조된 2쌍 모듈의 실측 값을 비교함으로써 모듈 설계를 위한 접근방법을 검토하였다. 2쌍 모듈의 계산된 저항과 측정된 저항은 각각 $T_h$=833 K에서 0.954 $\Omega$과 1.105 $\Omega$으로 약 0.15 $\Omega$ 정도의 차이로 근접한 결과를 얻었으며, 제시된 방법으로 고온산화물 열전 모듈 제작에 유효하다고 판단된다.

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.181-186
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• 2008

2,5-Di-(2'-hydroxyethoxy)-4'-nitrostilbene (3) was prepared and polycondensed with terephthaloyl chloride, adipoyl chloride, and sebacoyl chloride to yield novel T-type polyesters (4-6) containing the NLO-chromophores dioxynitrostilbenyl groups, which constituted parts of the polymer backbones. Polymers 4-6 are soluble in common organic solvents such as acetone and N,N-dimethylformamide. They showed thermal stability up to 260 oC in thermogravimetric analysis with glass-transition temperatures obtained from differential scanning calorimetry in the range 90-95 oC. The second harmonic generation (SHG) coefficients (d33) of poled polymer films at the 1064 nm fundamental wavelength were around 1.42 ´ 10-9 esu. The dipole alignment exhibited high thermal stability up to 5 oC higher than glass-transition temperature (Tg), and there was no SHG decay below 100 oC due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications.

• 한국수소및신에너지학회논문집
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• 제14권4호
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• pp.298-304
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• 2003

The thermal behavior of $NiFe_2O_4$ prepared by a solid-state reaction was investigated for $H_2$ generation by the thermochemical cycle. The reduction of $NiFe_2O_4$ started from $800^{\circ}C$, and the weight loss was 0.2-0.3 wt% up to $1000^{\circ}C$. In the $H_2O$ decomposition reaction, $H_2$ was generated by oxidation of reduced $NiFe_2O_4$. The crystal structure of $NiFe_2O_4$ maintained during the redox reaction of 5 cycles. From this observation, the lattice oxygen in $NiFe_2O_4$ is released without the structural change during the thermal reduction and oxygen deficient $NiFe_2O_4$ can be restored to the spinel structure of $NiFe_2O_4$.