• 한국결정성장학회지
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• 제8권3호
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• pp.424-430
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• 1998

MONOS(metal-oxide-nitride-oxide-semicondutor) EEPROM에 응용하기 위한 얇은 ONO 유전층의 막 특성을 AES, SIMS, TEM 및 AFM을 이용하여 조사하였다. 터널링 산화막, 질화막, 블로킹 산화막의 두께를 각각 달리하여 ONO 박막을 제작하였다. 터널링 산화막 위에 LPCVD방법으로 질화막을 증착하는 동안 얇은 터널링 산화막이 질화되었으며, 질화막 위에 블로킹 산화막을 형성할 때, 산소가 질화막 표면을 산화시킬 뿐만 아니라 질화막을 지나 확산되었다. ONO 박막은 $SiO_2$(블로킹 산화막)/O-rich SiOxNy(계면)/N-rich iOxNy(질화막)/O-rich SiOxNy(터널링 산화막)으로 이루어졌다. SiON상은 주로 터널링 산화막과 질화막, 질화막과 블로킹 산화막 계면에 분포하였으며, $Si_2NO$상은 각 계면의 질화막 쪽과 터널링 산화막 내에 분포하였다.

• 한국위성정보통신학회논문지
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• 제10권2호
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• pp.90-94
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• 2015

본 연구에서는 Solution Process를 적용한 Strontium Oxide를 배향막으로 사용한 경우의 액정배향 특성에 대해서 연구하였다. Stronium Oxide 는 High K 물질로 배향막으로 사용할 경우 임계치 전압을 효율적으로 조절할 수 있는 장점이 있으나, 액정분자와의 배향에 관한 상호관계에 대해서는 많은 연구가 진행되지 않았었다. 0.1~0.4 Mol 롤 농도를 조절한 Strontium Oxide를 Solution Process 로 배향막으로서 제조함으로써, 보다 생산성이 좋은 방법을 제시할 수 있었으며, 재료가 갖는 우수한 특성을 반영한 액정디스플레이의 제조가 가능하였다. 샘플 측정결과 1.447~1.613V 의 임계치 전압특성을 보여주어 기존의 방법으로 제조된 액정디스플레 이와 동등 혹은 우월한 특성을 갖고 있음을 알 수 있었다.

• Journal of Chest Surgery
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• 제33권2호
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• pp.132-138
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• 2000

Background: Inhaled nitric oxide therapy causes selective pulmonary vasodilation in congenital heart diseases with pulmonary hypertension. However discontinuation of inhaled nitric oxide therapy may be complicated by abrupt life-threatening rebound pulmonary hypertension(RPH) The purpose of this study was to prevent by comparing group I(without RPH n=13) and group II(with RPH n=6) to determine the risk factors involved inthe development of the RPH. Material and Method: Between Januarty 6, 1998 and April 14, 1999. we studied 19 consecutive children who were treated with inhaled nitric oxide for clinically significant pulmonary hypertension after an open heart surgery for congenital heart disease. the ratio of males and females was 12:7 ranging in age from 10 days to 6040 days(16 years) To identify the effects of nitric oxide between two groups we measured heart rate mean and systolic pulmonary arterial pressure mean and systolic systemic arterial pressure central venous pressure pH paO2/FiO2 and O2 saturation before and after the initiation and just before the withdrawal of the inhaled nitric oxide. result: In 6 of 19 patients(32%) withdrawal of inhaled nitric oxide caused RPH. In the two groups inhaled nitrix oxide decreased in pulmonary arterial pressure(PAP) without decreasing the systemic arterial pressure(SAP) and increased PaO2/FiO2 Compared with patients who had no RPH(group I) patients who had RPH(group II) were older in age (1204$\pm$1688 versus 546$\pm$1654 days p<0.05) received less nitric oxide therapy(34$\pm$18 versus 67$\pm$46 hours p<0.05) has shorter weaning process(5$\pm$3 versus 15一13 hours p<0.05) and received lowerconcentration of initial nitric oxide supply(11$\pm$8 versus 17$\pm$8 ppm p>0.05) and lower concentration just before the withdrawal nitric oxide(4.2$\pm$2.6 versus 5.6$\pm$2.6 ppm, p>0.05) Conclusion : We speculate that older age shorter of nitric oxide therapy shorter weaning process are the risk factors of RPH.

• 한국재료학회지
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• 제29권10호
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• pp.609-616
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• 2019

Oxide coatings are formed on die-cast AZ91D Mg alloy through an environmentally friendly plasma electrolytic oxidation(PEO) process using an electrolytic solution of $NaAlO_2$, KOH, and KF. The effects of PEO condition with different duty cycles (10 %, 20 %, and 40 %) and frequencies(500 Hz, 1,000 Hz, and 2,000 Hz) on the crystal phase, composition, microstructure, and micro-hardness properties of the oxide coatings are investigated. The oxide coatings on die-cast AZ91D Mg alloy mainly consist of MgO and $MgAl_2O_4$ phases. The proportion of each crystalline phase depends on various electrical parameters, such as duty cycle and frequency. The surfaces of oxide coatings exhibit as craters of pancake-shaped oxide melting and solidification particles. The pore size and surface roughness of the oxide coating increase considerably with increase in the number of duty cycles, while the densification and thickness of oxide coatings increase progressively. Differences in the growth mechanism may be attributed to differences in oxide growth during PEO treatment that occur because the applied operating voltage is insufficient to reach breakdown voltage at higher frequencies. PEO treatment also results in the oxide coating having strong adhesion properties on the Mg alloy. The micro-hardness at the cross-section of oxide coatings is much higher not only compared to that on the surface but also compared to that of the conventional anodizing oxide coatings. The oxide coatings are found to improve the micro-hardness with the increase in the number of duty cycles, which suggests that various electrical parameters, such as duty cycle and frequency, are among the key factors controlling the structural and physical properties of the oxide coating.

• KSBB Journal
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• 제23권5호
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• pp.369-374
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• 2008

Rhdotorula glutinis epoxide hydrolase 유전자를 pColdI 벡터 와 pET-21b(+) 벡터에 재조합하여 제작한 E. coli를 생촉매로 사용하여 라세믹 styrene oxide에 대하여 회분식 가수분해 반응을 실시하였다. pET-21b(+)/RgEH 재조합 플라스미드 DNA를 가진 E. coli를 $15^{\circ}C$에서 저온 배양할 때 수용성 단백질 형태로 가장 많이 발현되었고, 입체선택적 가수분해 활성과 촉매 안정성이 가장 좋았다. 라세믹 styrene oxide 20 mM에 대하여 반응온도 $30^{\circ}C$에서는 반응시간 20분 동안에 수율 24.0%로 (S)-styrene oxide를 얻은 반면에, 반응온도를 $10^{\circ}C$로 낮추고 0.5% (w/v) Tween 20을 첨가하고 반응시키면 광학순도 99.0% ee 이상의 (S)-styrene oxide을 46.0%의 수율로 얻을 수 있었다. 최적조건에서 E 값은 6.68이었으며, 100 mM의 라세믹 styrene oxide에 대해서는 반응시간 50분에 이론 수율 50% 대비 40%의 높은 수율로 (S)-styrene oxide를 얻을 수 있었다.

• Transactions on Electrical and Electronic Materials
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• 제14권5호
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• pp.250-253
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• 2013

In this paper, we fabricated 3D pillar type silicon-oxide-nitride-oxide-silicon (SONOS) devices for high density flash applications. To solve the limitation between erase speed and data retention of the conventional SONOS devices, bandgap-engineered (BE) tunneling oxide of oxide-nitride-oxide configuration is integrated with the 3D structure. In addition, the tunneling oxide is modulated by another method of $N_2$ ion implantation ($N_2$ I/I). The measured data shows that the BE-SONOS device has better electrical characteristics, such as a lower threshold voltage ($V_{\tau}$) of 0.13 V, and a higher $g_{m.max}$ of 18.6 ${\mu}A/V$ and mobility of 27.02 $cm^2/Vs$ than the conventional and $N_2$ I/I SONOS devices. Memory characteristics show that the modulated tunneling oxide devices have fast erase speed. Among the devices, the BE-SONOS device has faster program/erase (P/E) speed, and more stable endurance characteristics, than conventional and $N_2$ I/I devices. From the flicker noise analysis, however, the BE-SONOS device seems to have more interface traps between the tunneling oxide and silicon substrate, which should be considered in designing the process conditions. Finally, 3D structures, such as the pillar type BE-SONOS device, are more suitable for next generation memory devices than other modulated tunneling oxide devices.

• 열처리공학회지
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• 제20권6호
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• pp.299-305
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• 2007

The effect of spray deposition of oxide particles on oxidation behaviors of as-cast Mo-14.2Si-9.6B (at%) alloys at $1200^{\circ}C$ up to for 100 hrs has been investigated. Various oxide powders are utilized to make coatings by spray deposition, including $SiO_2,\;TiO_2,\;ZrO_2,\;HfO_2$ and $La_2O_3$. It is demonstrated that the oxidation resistance of the cast Mo-Si-B alloy can be significantly improved by coating with those oxide particles. The growth of the oxide layer is reduced for the oxide particle coated Mo-Si-B alloy. Especially, for the alloy with $ZrO_2$ coating, the thickness of oxide layer becomes only one fifth of that of uncoated alloys when exposed to in air for 100 hrs. The reduction of oxide scale growth of the cast Mo-Si-B alloy due to oxide particle coatings are discussed in terms of the change of viscosity of glassy oxide phases that form during oxidation at high temperature.

• Environmental Analysis Health and Toxicology
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• 제15권3호
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• pp.61-67
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• 2000

Toxic lesions of styrene in the Japanese Medaka (Oryzias latipes) were compared with those of styrene oxide, the active metabolite of styrene, using embryo-larval assays. The developmental stages of Japanese Medaka (Oryzias latipes) treated with both chemicals were not altered and progressed normally. However, styrene oxide was more toxic than styrene in terms of causing death and lesions . High concentrations of styrene (higher than 4.9 ppm) and styrene oxide (higher than 2.4 ppm), resulting in more than 50% mortality, caused similar lesions of cardiovascular system, craniofacial bone formation and spinal deformities, although a number of lesions were not observed by both chemicals . In the group treated with styrene, eyeball sizes and intereye distances were reduced, while, in the group treated with styrene oxide , the eyes and eye cups were not developed and two eyes were sometimes fused. In addition, styrene oxide caused the lesion which involved the posterior brain and brain stem were herniated through the spinal cord . The noticeable difference of toxic symptoms between these two chemicals was the time of onset. Toxicities of cardiovascular system and craniofacial bone formation appeared on day 3 of development in styrene oxide treated group, but, styrene treated group staned to show hemorrhages on day 3 and the craniofacial malformation were appeared on day 5, These differences between two chemicals may be due to the metabolism of styrene to styrene oxide, the reactive intermediate.

• 한국콘텐츠학회논문지
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• 제9권7호
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• pp.211-217
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• 2009

본 연구에서는 알긴산올리고당의 일부 방사선 방어효과를 규명하기 위해 마우스에 3 Gy 선량의 방사선을 1회 전신 조사하여 방사선 유도 nitric oxide를 측정하였다. 측정결과 방사선조사 대조군에서 nitric oxide 생성이 하강된 반면 방사선조사 전 3일간 처치군 및 방사선조사 후 3일간 처치군에서 유의한 생성 증가를 보였고, 특히 방사선조사 전 3일간 처치군에서 가장 큰 차이를 보였다(P<0.001). 결론적으로, 항산화효과가 탁월한 알긴산올라고당은 nitric oxide의 생성 증가를 촉진시킴으로써 일부 방사선 방어작용을 수행한다는 사실을 규명하였고, 화학적 독성이 적은 자연산생물이 방사선방어제로 활용될 수 있음을 확인하였다.

• E2M - 전기 전자와 첨단 소재
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• 제7권2호
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• pp.145-151
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• 1994

The multi-dielectric layer SiOz/Si3N4/SiO2(ONO) is used to scale down the memory device. In this paper, the change of composition in ONO layer due to the process condition and the conduction mechanism are observed. The composition of the oxide film grown through the oxidation of nitride film is analyzed using auger electron spectroscopy(AES). AES results show that oxygen concentration increases at the interface between oxide and nitride layers as the thickness -of the top oxide layer increases. Results of I-V measurement show that the insulating properties improve as the thickness of the top oxide layer increases. But when the thickness of the nitride layer decreases below 63.angs, insulating peoperties of film 28.angs. of top oxide and film 35.angs. turn over showing that insulating property of film 28.angs. of top oxide is better than that of film 35.angs. of top oxide. This phenomenon of turn over is thought as the result of generation of surface state due to oxygen flow into nitride during oxidation process. As the thickness of the top oxide and nitride increases, the electrical breakdown field increases, but when the thickness of top oxide reaches 35.angs, the same phenomenon of turn over occurs. Optimum film thickness for scaled multi-layer dielectric of memory device SONOS is estimated to be 63.angs. of nitride layer and 28.angs. of top oxide layer. In this case, maximum electrical breakdown field and leakage current are 18.5[MV/cm] and $8{\times}{10^-12}$[A], respectively.