• JSTS:Journal of Semiconductor Technology and Science
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• 제1권4호
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• pp.202-208
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• 2001

In Recent results suggested that doping $Ta_2O_5$ with a small amount of $TiO_2$ using standard ceramic processing techniques can increase the dielectric constant of $Ta_2O_5$ significantly. In this paper, this concept is studied using RTCVD (Rapid Thermal Chemical Vapor Deposition). Ti-doped $Ta_2O_5$ films are deposited using $TaC_{12}H_{30}O_5N$, $C_8H_{24}N_4Ti$, and $O_2$ on both Si and $NH_3$-nitrided Si substrates. An $NH_3$-based interface layer at the Si surface is used to prevent interfacial oxidation during the CVD process and post deposition annealing is performed in $H_2/O_2$ ambient to improve film quality and reduce leakage current. A sputtered TiN layer is used as a diffusion barrier between the Al gate electrode and the $TaTi_xO_y$ dielectric. XPS analyses confirm the formation of a ($Ta_2O_5)_{1-x}(TiO_2)_x$ composite oxide. A high quality $TaTi_xO_y$ gate stack with EOT (Equivalent Oxide Thickness) of $7{\AA}$ and leakage current $Jg=O.5A/textrm{cm}^2$ @ Vg=-1.0V has been achieved. We have also succeeded in forming a $TaTi_x/O_y$ composite oxide by rapid thermal oxidation of the as-deposited CVD TaTi films. The electrical properties and Jg-EOT characteristics of these composite oxides are remarkably similar to that of RTCVD $Ta_2O_5, suggesting that the dielectric constant of $Ta_2O_5$ is not affected by the addition of $TiO_2$.

• 펄프종이기술
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• 제33권1호
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• pp.73-79
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• 2001

Stricter environmental demands have increased the need to replace conventional C/D bleaching sequence by chlorine-free sequence. Permanganate is well known as a powerful oxidant and have been used industrially in variable fields. However, it has considered to be difficult to use permanganate as a bleaching reagent because of its strong oxidative effect decreasing the viscosity of pulps extremely. We have tried to use permanganate as a bleaching reagent for KP under the mild condition and it was clear that pernanganate oxidized lignin remained in pulps selectively and increased pulp brightness decreasing K number of pulps with small degradation of cellulose. We have employed the neutral condition in the permanganate bleaching process in this study. In this case, permanganate was converted to manganese dioxide after bleaching reaction. The manganese dioxide is remained in the treated pulp fibers because of its insolublity in water. So it was required to reduction the manganese oxide to manganese ion by using reductants with acid. In this paper, we proposed to use oxalic acid as a reducing reagent converting manganese oxide to manganese ion after bleaching reaction. Oxalic acid plays the role as a reductant and a acid, so post-treatment after bleaching became to be easy by using oxalic acid. On the study using lignin model compounds, it was clear that permaganate react with phenols firstly, after that oxalic acid reduce the manganese oxide to manganese ion in the mixture of permanganate, phenols and oxalic acid. Several lignin model compounds ($\textit{p}$-hydroxybenzaldehyde, vanillin, syringaldehyde, veratraldehyde) are selected to elucidate the effect of substituents on reaction rate and its mechanism with permanganate including oxalic acid in this study. Except for veratraldehyde, the rate of oxidative degradation of phenolic compounds by permanganate with oxalic acid are higher than neutral condition. Especially, the degradation rate of $\textit{p}$-hydroxybenzaldehyde are strongly dependent on pH of reaction mixture. On the other hand, the degradation rate of veratraldehyde are decreased with decreasing pH and main degradation product is veratric acid. This result indicate that pH of bleaching liquor should be kept over 2 to degrade of non-phenolic lignin in the pulps effectively in permanganate bleaching.

• Asian-Australasian Journal of Animal Sciences
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• 제30권12호
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• pp.1756-1763
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• 2017

Objective: The study aimed at assessing the effects of frozen storage duration on quality characteristics, lipid oxidation and sensory quality of various horse muscles. Methods: Five representative muscles: longissimus dorsi (LD), gluteus medius (GM), semimembranosus (SM), biceps femoris (BF), and triceps brachii (TB) at 24 h post-mortem obtained from 28-mo-old Jeju female breed horses (n = 8) were used in the present investigation. The muscles were vacuumpackaged and frozen at $-20^{\circ}C$ for 120, 240, and 360 days. All the samples were analyzed for thawing and cooking losses, pH, Warner-Bratzler shear forces (WBSF), color traits, total volatile basic nitrogen (TVBN), thiobarbituric acid reactive substances (TBARS) and sensory traits. The muscle samples analyzed on day 0 of frozen storage (fresh, non-frozen) were used for comparison. Results: Results revealed that thawing and cooking losses significantly (p<0.05) increased in all the muscles after 120 days and then remained unchanged up to 360 days of frozen storage. The TBARS and TVBN contents significantly increased as increasing frozen storage time up to 360 days (p<0.05). While, significant decreases in WBSF values were observed for all the muscles with increased frozen storage time (p<0.05). Frozen storage variously affected the color traits of the muscles for instance; the redness of LD, GM, and BF muscles showed a decreasing tendency during frozen storage while it was not changed in TB and SM muscles. Furthermore, the frozen storage did not produce detrimental effects on sensory quality as it did not cause flavor and juiciness defects whereas it partially improved the tenderness of all the muscles studied. Conclusion: Based on the results obtained from our work, it is concluded that frozen storage could be applied to increase the long-term shelf life of horsemeat while still retaining its sensory quality.

• 한국재료학회지
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• 제5권7호
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• pp.835-841
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• 1995

Si$_3$N$_4$가 추진기관 연소조건 하에서 흑연의 산화와 마모를 효과적으로 방지하는 다층 코팅재료로 쓰일 수 있도록 하기 위하여 저압화학기상증착법(LPCVD)으로 Si$_3$N$_4$를 코팅할 때의 증착특성에 대해 연구하였다. 흑연 위에 pack cementation방법으로 SiC를 코팅하고 그 위에 저압화학기상증착법으로 Si$_3$N$_4$를 코팅 하였으며, 증착온도와 반응기체입력비를 변화시키면서 이에 따른 증착속도와 표면형상의 변화를 관찰하였다. 증착속도는 증착온도가 높아짐에 따라 처음에는 증가하다가 최대값을 나타낸 후 감소하는 경향을 나타냈으며, 그레인의 크기는 증착온도가 높아짐에 따라 작아지는 경향을 보였다. 한편, 반응기체의 입력비가 20$\leq$NH$_3$/SiH$_4$$\leq$40인 조건에서는 증착속도의 변화나 표면형상의 변화를 관찰할 수 없었다. 증착온도 800~130$0^{\circ}C$ 범위에서 증착된 Si$_3$N$_4$가 비정질상인 것을 XRD로 확인할 수 있었으며 130$0^{\circ}C$, 질소 분위기에서 2시간 동안 열처리하여 결정상인 Si$_3$N$_4$를 인을 수 있었다.

• 센서학회지
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• 제4권3호
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• pp.51-59
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• 1995

실리콘기판 위에 스트레스균형이 이루어진 150 nm-$Si_{3}N_{4}$/300 nm-$SiO_{2}$/150 nm-$Si_{3}N_{4}$ 구조의 평탄한 유전체 멤브레인을 제작하였다. 이 멤브레인의 스트레스 특성평가를 위하여 stress-deflection, stress-temperature 및 스트레인 진단용 시험패턴의 특성을 측정분석하였고, 중간에 있는 $SiO_{2}$층을 PECVD, LPCVD 및 APCVD방법으로 각각 증착하여 $SiO_{2}$층의 증착방법에 따른 적층 유전체박막의 스트레스특성에 대해서도 논의하였다. 대부분의 경우 적층 유전체 멤브레인에 인장스트레스가 존재하였으나, $SiO_{2}$층의 증착방법과 거의 무관하게 $1,150^{\circ}C$의 후습식산화로 실리콘기판에 의해 멤브레인에 나타나는 인장스트레스의 균형을 얻을 수 있었다. 온도변화에 따른 멤브레인에서의 스트레스 변화특성으로 부터 후산화처리를 하지 않는 경우에는 중간의 $SiO_{2}$ 층으로 APCVD방법에 의해 증착된 LTO가 더 적합한 것으로 나타났다.

• 한국응용과학기술학회지
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• 제40권4호
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• pp.761-772
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• 2023

본 연구의 목적은 남자 대학 엘리트 조정선수의 2000 m 로잉 에르고미터 수행 후 저온침수 처치를 통해 혈중 젖산, LDH, MDA 및 SOD의 변화에 긍정적인 영향을 주어 피로 회복에 미치는 영향을 구명하는 데 있다. 이에 남자 대학 엘리트 조정선수 10명을 대상으로 고강도 로잉 에르고미터 2,000 m 수행 후 비 처치와 저온 침수 처치의 효과를 비교하였다. 측정 변인들에 대한 결과를 검증하기 위해 처치 및 시기 간 상호작용 효과를 분석하기 위해 ANOVA를 실시하였고 각 항목별 유의수준 .05로 설정하여 다음의 결과를 도출하였다. 젖산은 시기 간 주효과가 나타났고(p<.001) 그룹 내 시기별 차이가 났다(p<.001). 또한, LDH는 그룹 내 시기별 차이가 나타났다(p<.05). MDA는 그룹×시기 간 상호작용 효과가 나타났고(p<.05), 그룹 간(p<.05), 시기 간(p<.001) 주효과가 나타났다. SOD는 그룹 간, 시기 주효과가 나타났고(p<.05) 회복 30분 후 그룹 간 차이가 나타났다(p<.05). 이를 종합해 볼 때, 본 연구에서 실시한 저온침수 처치가 조정 선수의 혈중 피로 물질, 활성산소 및 항산화 효소에 유의한 효과를 나타냈다. 따라서 운동선수의 고강도 훈련 후 저온침수를 적극 활용할 것을 권장한다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권7호
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• pp.1059-1066
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• 2008

This study was carried out to investigate the effects of dietary sulfur (S) and vitamin E (Vit E) supplementation on the quality of beef from longissimus muscle of Hanwoo bulls. Eleven, 29 months-aged Hanwoo bulls were randomly divided into three feed supplementation groups (S (n = 4), Vit E (n = 4) and S+Vit E (n = 3)). S was given as much as 12 g/head/d and Vit E was given as much as 1,200 IU/head/d; both supplements were given for 3 months prior to slaughter. At 24 h post-slaughter, the carcasses were weighed and evaluated by official grader for carcass traits. At 48 h post-slaughter, the M. longissimus from each carcass was collected and stored at $4{\pm}0.2^{\circ}C$ for 10 days. There were no significant differences in yield and quality grades of carcass and proximate composition, physical properties and aroma pattern of meat among all groups. At 5 days of storage, the TBARS value of meat from cattle with S+Vit E supplementation was significantly lower (p<0.05) than other groups; and at 10 days of storage, the TBARS value of meat from cattle with Vit E and S+Vit E supplementations was significantly lower (p<0.05) than from cattle with S supplementation. At 5 days of storage, MetMb concentration of meat from cattle with S+Vit E supplementation was significantly lower (p<0.05) than from cattle with Vit E supplementation; and at 10 days of storage, MetMb concentration of meat from cattle with S+Vit E supplementation was significantly lower (p<0.05) than from other groups. At 10 days of storage, the redness value of meat from cattle with S supplementation was significantly higher (p<0.05) than from cattle with Vit E supplementation and the hue-angle value of meat from cattle with S and S+Vit E supplementations was significantly lower (p<0.05) than from cattle with Vit E supplementation. Dietary Vit E supplementation had a better effect on lipid stability whereas dietary S supplementation had a better effect on OxyMb stability. The dietary combination of S and Vit E created the highest protection for beef from myoglobin oxidation and thus improved the color stability of meat.

• 마이크로전자및패키징학회지
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• 제27권3호
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• pp.41-47
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• 2020

비메모리 반도체 미세 Cu배선의 전기적 신뢰성 향상을 위해 SiN_x 피복층(capping layer)과 Cu 배선 사이 50 nm 두께의 Co 박막층 삽입이 계면 신뢰성에 미치는 영향을 double-cantilever beam (DCB) 접착력 측정법으로 평가하였다. DCB 평가 결과 SiN_x/Cu 구조는 계면접착에너지가 0.90 J/㎡이었으나 SiN_x/Co/Cu 구조에서는 9.59 J/㎡으로 SiN_x/Cu 구조보다 약 10배 높게 측정되었다. 대기중에서 200℃, 24시간 동안 후속 열처리 진행한 결과 SiN_x/Cu 구조는 0.93 J/㎡으로 계면접착에너지의 변화가 거의 없는 것으로 확인되었으나 SiN_x/Co/Cu 구조에서는 2.41 J/㎡으로 열처리 전보다 크게 감소한 것을 확인하였다. X-선 광전자 분광법 분석 결과 SiN_x/Cu 도금층 사이에 Co를 증착 시킴으로써 SiN_x/Co 계면에 CoSi₂ 반응층이 형성되어 SiN_x/Co/Cu 구조의 계면접착에너지가 매우 높은 것으로 판단된다. 또한 대기중 고온에서 장시간 후속 열처리에 의해 SiN_x/Co 계면에 지속적으로 유입된 산소로 인한 Co 산화막 형성이 계면접착에너지 저하의 주요인으로 판단된다.

• 한방재활의학과학회지
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• 제26권2호
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• pp.29-50
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• 2016

Objectives There is few Korean medicinal studies about post-operation wound healing despite much effort for minimizing wound or post-op scar. The aim of this study is to evaluate the wound healing effect of Gyejibokryeong-hwan (Guizhifuling-wan, GBH) after skin suture. Methods < In vitro > We observed anti-oxidative and anti-inflammatory effect by using lipopolysaccharide (LPS)-treated RAW 264.7 cells. For anti-oxidation, we mesured the total amount of polyphenol, flavonoid, DPPH scavenging ability, ABTS scavenging ability and the value of ROS production, and for anti-inflammation, we mesured the amount of NO and pro-inflammatory cytokines ($TNF-{\alpha}$, $IL-1{\beta}$, IL-6). < In vivo > Thirty SD rats were divided into five equal groups (n=6, one normal, two controls and two experimentals). All groups except normal group were made a scar (around $1{\times}4cm^2$) in the back by the depth of the fascia and then sutured by a thread and needle. Normal group rats received no treatment at all. Control group rats were fed distilled water, and positive control group rats were percutaneously applied terramycin once in 2 days. GBH 200 group rats were orally medicated GBH 200 mg/kg, and GBH 400 group rats were orally medicated GBH 400 mg/kg per day for two weeks. We analyzed the blood samples (WBC, neutrophil, lymphocyte, monocyte, eosinophil), and the serums (TIMP-1, MMP-2, MMP-2. $PGE_2$, $TGF-{\beta}$, VEGF), and examined the wounded skin tissue histopathologically. Results < in vitro > 1. DPPH and ABTS scavenging activity was increased concentration-dependantly, and ROS production was significantly increased in GBH treated cells ($100{\mu}g/ml$). Therefore in this study, Gyejibokryeong-hwan appears to have the anti-oxidative. 2. NO production was significantly reduced in GBH treated cells ($100{\mu}g/ml$), and $IL-1{\beta}$ production was significantly reduced in GBH treated cells ($1{\mu}g/ml$). But, $TNF-{\alpha}$ and IL-6 did not show uneffective action. Therefore in this study, Gyejibokryeong-hwan did not show any significant effect on anti-inflammatory process. < in vivo > 1. Monocyte and neutrophil was significantly increased in GBH (200, 400) groups. WBC, lymphocyte and eosinophil did not show significant change. 2. TIMP-1, MMP-2, VEGF were significantly increased in GBH 400 group, $PGE_2$ was significantly reduced in GBH 400 group. $TGF-{\beta}$ was significantly increased in GBH (200, 400) groups, and MMP-9 was increased concentration-dependantly in GBH groups, but there was no significance. 3. In histopathological examinations, collagen was significantly increased and keratin was significantly decreased in GBH (200, 400) groups. Conclusions According to in vitro experiment, GBH appears to have the anti-oxidative effect and in vivo experiment, GBH stimulate the wound healing process hematologically and histopathologically. In conclusion, the results suggest that GBH promotes wound healing after skin suture.

• Tuberculosis and Respiratory Diseases
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• 제73권1호
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• pp.22-31
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• 2012

Background: Oxidation plays an important role in acute lung injury. This study was conducted in order to elucidate the effect of repetitive post-treatment of N-acetylcysteine (NAC) in lipopolysaccaride (LPS)-induced acute lung injury (ALI) of rats. Methods: Six-week-old male Sprague-Dawley rats were divided into 4 groups. LPS (Escherichia coli 5 mg/kg) was administered intravenously via the tail vein. NAC (20 mg/kg) was injected intraperitoneally 3, 6, and 12 hours after LPS injection. Broncho-alveolar lavage fluid (BALF) and lung tissues were obtained to evaluate the ALI at 24 hours after LPS injection. The concentration of tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$) and interleukin $1{\beta}$ (IL-$1{\beta}$) were measured in BALF. Nuclear factor ${\kappa}B$ (NF-${\kappa}B$), lipid peroxidation (LPO), and myeloperoxidase (MPO) were measured using lung tissues. Micro-computed tomography (micro-CT) images were examined in each group at 72 hours apart from the main experiments in order to observe the delayed effects of NAC. Results: TNF-${\alpha}$ and IL-$1{\beta}$ concentration in BALF were not different between LPS and NAC treatment groups. The concentration of LPO in NAC treatment group was significantly lower than that of LPS group ($5.5{\pm}2.8$ nmol/mL vs. $16.5{\pm}1.6$ nmol/mL) (p=0.001). The activity of MPO in NAC treatment group was significantly lower than that of LPS group ($6.4{\pm}1.8$ unit/g vs. $11.2{\pm}6.3$ unit/g, tissue) (p<0.048). The concentration of NF-${\kappa}B$ in NAC treatment group was significantly lower than that of LPS group ($0.3{\pm}0.1\;ng/{\mu}L$ vs. $0.4{\pm}0.2\;ng/{\mu}L$) (p=0.0001). Micro-CT showed less extent of lung injury in NAC treatment than LPS group. Conclusion: After induction of ALI with lipopolysaccharide, the therapeutic administration of NAC partially attenuated the extent of ALI through the inhibition of NF-${\kappa}B$ activation.