• Journal of Information Display
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• 제4권1호
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• pp.1-8
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• 2003

Recent progress in both low pretilt and high pretilt defect free C1 surface stabilized ferroelectric liquid crystal (SSFLC) devices is reviewed. First, by numerical calculation to investigate the balance between surface azimuthal anchoring energy and bulk elastic energy within the confined chevron layer geometry of C1 and C2, it is possible to achieve a zigzag free C1 state by low azimuthal anchoring alignment with a low pretilt angle. The critical azimuthal anchoring coefficient for defect free C1 state is calculated. Its relationship with elastic constant, chevron angle as well as surface topography effect are also discussed. Second, using $5^{\circ}$ oblique SiO deposition alignment method a defect free, large memory angle, high contrast ratio and bistable C1 SSFLC display, which has potential for electronic paper applications has also been developed. The electrooptical properties and bistability of this device have been investigated. Various aspects of defect control are also discussed.

• Journal of Pharmaceutical Investigation
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• 제4권4호
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• pp.38-45
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• 1974

Sulfur had been used for the medical fields as fungacidal bacteriocides and gelatolytic agent from ancient B. C 700, their prepartiones contained the sulfur are restrict to freely medication, the restrutive reasones are the it's preparation stabilized sparing solubility, and limit to pharmaceutical development of colloidal sulfur-self. Anthors prepared white lotion, registered on U.S.P XIII from the colloidal sulfur, by the method midified buku zawa make the stabilized lotion by the various fatty alkyl sulfates, and the result obtained are as follows the suspending agents for stabilize to the colloidal sulfur are the fatty alcohol sulfates than natural clay on the imbibition appeareuce and usefulnss. The adequate quantities of stearic acid in lotion base are $1.5{\sim}2.0$ percent for refluidity and pourability. The carbon numbers in alkyl radical used fatty alcohol sulfates as anionic surfactants are maxture of $12{\sim}18$ about efficiency, as possible as, the electrolyte is removed from the white lotion.

• 한국식품영양학회지
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• 제37권1호
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• pp.48-56
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• 2024

Effects of glutamic acid (Glu) and monosodium glutamate (MSG) on oxidative stability of oil-in-water (O/W) emulsions with different emulsifier charges during riboflavin (RF) photosensitization were evaluated by analyzing headspace oxygen content and conjugated dienes. Cetyltrimethylammonium bromide (CTAB), Tween 20, and sodium dodecyl sulfate (SDS) were used as cationic, neutral, and anionic emulsifiers, respectively. Glu acted as an antioxidant in CTAB- and Tween-20-stabilized O/W emulsions during RF sensitization, whereas Glu acted as prooxidants in SDS-stabilized O/W emulsions in the dark. However, adding MSG did not have a constant impact on the degree of oxidation in O/W emulsions irrespective of the emulsifier charge. In RF-photosensitized O/W emulsions, the emulsifier charge had a greater influence on antioxidant properties of Glu than on those of MSG.

• Corrosion Science and Technology
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• 제12권6호
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• pp.265-273
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• 2013

Ti-stabilized 11 wt% Cr ferritic stainless steels (FSSs) for automotive exhaust systems have been experienced intergranular corrosion (IC) in some heat-affected zone (HAZ). The effects of sensitizing heat-treatment and silicon on IC were studied. Time-Temperature-Sensitization (TTS) curves showed that sensitization to IC was observed at the steels heat-treated at the temperature lower than $650^{\circ}C$ and that silicon improved IC resistance. The sensitization was explained by chromium depletion theory, where chromium is depleted by precipitation of chromium carbide during sensitizing heat-treatment. It was confirmed with the results from the analysis of precipitates as well as the thermodynamical prediction of stable phases. In addition, the role of silicon on IC was explained with the stabilization of grain boundary. In other words, silicon promoted the formation of the grain boundaries with low energy where precipitation was suppressed and consequently, the formation of Cr-depleted zone was retarded. The effect of silicon on the formation of grain boundaries with low energy was proved by the analysis of coincidence site lattice (CSL) grain boundary, which is a typical grain boundary with low energy.

• Geomechanics and Engineering
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• 제32권6호
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• pp.639-652
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• 2023

Stepped earth slopes incorporated with anti-slide piles are widely utilized in landslide disaster preventions. Explicit consideration of the three-dimensional (3D) effect in the slope design warrants producing more realistic solutions. A 3D limit analysis of the stability of pile stabilized stepped slopes is performed in light of the kinematic limit analysis theorem. The influences of seismic excitation and surcharge load are both considered from a kinematic perspective. The upper bound solution to the factor of safety is optimized and compared with published solutions, demonstrating the capability and applicability of the proposed method. Comparative studies are performed with respect to the roles of 3D effect, pile location, pile spacing, seismic and surcharge loads in the safety assessments of stepped slopes. The results demonstrate that the stability of pile reinforced stepped slopes differ with that of single stage slopes dramatically. The optimum pile location lies in the upper portion of the slope around L_x/L = 0.9, but may also lies in the shoulder of the bench. The pile reinforcement reaches 10% universally for a looser pile spacing D_c/d_p = 5.0, and approaches 70% when the pile spacing reaches D_c/d_p = 2.0.

• Applied Microscopy
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• 제41권4호
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• pp.277-284
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• 2011

강한 산화력과 소독효과로 인해 광범위하게 사용되고 있는 안정화 이산화염소(S-$ClO_2$)의 근육조직에 대한 부패억제 효과를 알아보고자 본 연구를 수행하였다. 본 실험을 위해 8주령 SD계 흰쥐 골격근(skeletal muscle)을 사용하였고, 안정화 이산화염소를 처리하지 않은 대조군과, 안정화 이산화염소의 분말과 수용액을 처리한 실험군으로 분류하여 광학 및 투과전자현미경으로 관찰하였다. 광학현미경 관찰 결과, 대조군 1일부터 근섬유막이 분리되기 시작하였고 핵의 붕괴가 관찰되었다. 2일군에서는 근섬유막이 붕괴되어 근섬유의 형태만 남아 있었고, 근원섬유도 붕괴되는 양상을 나타내었다. 3일군 이후 대조군의 경우는 대부분의 근섬유막과 결합조직의 붕괴로 근섬유의 구분이 불분명하였다. 실험군의 경우, 3일군에서 근섬유 사이 결합조직의 부분적인 붕괴가 관찰되었다. 그러나 4, 5일군에서도 3일군과 유사한 양상을 나타내었다. 한편, 전자현미경적 소견은 대조군의 경우 1일군부터 근섬유막의 붕괴로 근섬유의 경계가 불분명하였고, 미토콘드리아막도 부분적인 파괴가 관찰되었다. 2일째부터 근섬유막이 모두 붕괴되었고 근섬유 사이에서 세균이 관찰되었다. 3일군 이후는 근육의 형태를 구별할 수 없었다. 그러나 실험군의 경우, 1일과 2일군은 전형적인 근육의 미세구조를 관찰할 수 있었고, 3일군부터 부분적인 미토콘드리아막의 붕괴가 관찰되었다. 이후 시간경과에 따라 결합조직이 붕괴되어 동심원상의 구조물이 일부 관찰되었다. 따라서 본 연구결과, 대조군은 1일군부터 조직의 붕괴가 시작되어 3일군 이후는 대부분 붕괴되어 형태를 구분할 수 없었으나, 실험군의 경우는 3일군부터 부분적인 붕괴가 시작되었고 이후 시간이 경과되어도 전체적인 근육의 형태가 유지되어 안정화 이산화염소가 근육에 부패억제 효과가 있는 것으로 확인되었다.

• 콘크리트학회논문집
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• 제19권6호
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• pp.745-754
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• 2007

이 논문은 철근콘크리트 구조 부재의 인장증강효과에 대한 해석적 모델을 제안한 것이다. 이 모델의 정식화를 위해 철근과 콘크리트 경계면에서 발생하는 실제와 유사한 형태의 부착응력과 미끌림 특성과 쪼갬균열의 영향을 고려하였다. 균열 안정화 단계에서의 철근 경계면 미끌림 분포를 선형으로 가정하고, 균열이 발생한 부재의 중앙 단면에서 콘크리트의 분담력이 일정하다는 조건을 CEB-FIP Model Code 1990 및 Eurocode 2에서 제시하고 있는 부착응력-미끌림 관계에 적용하였다. 이로부터 균열 안정화단계에서 부착응력에 의해 철근의 매입길이 방향으로 변화하는 철근의 변형률과 콘크리트 분담력을 계산할 수 있는 평형방정식을 유도하고, 변형적합조건을 고려하여 철근의 평균 변형률과 콘크리트 평균 분담력으로 동시에 표현이 가능한 인장강성 계수를 제안하였다. 이로부터 새롭게 정식화된 인장증강효과 모델을 기존 문헌에 발표된 여러 연구자들의 실험 자료에 적용하여 그 정확성을 검증한 결과, 제안식에 의한 예측값은 실험값을 비교적 정확하게 예측하는 것으로 나타났다.

• Geomechanics and Engineering
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• 제22권2호
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• pp.143-152
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• 2020

In this research, soil samples of the Kerman sedimentary basin, Iran, were investigated through laboratory tests such as petrography (Scanning Electron Microscopy (SEM), X-Ray Fluorescence Spectroscopy (XRF) and X-Ray Diffraction (XRD)), physical and mechanical characteristics tests. The soil in this area is dominantly CL. The petrography results showed that the dominant clay mineral is Illite. This soil has made some problems in the earth dams due to the low shear strength. In this study, a set of samples were prepared by adding different amounts of lime. Next, the petrography and strength tests at the optimum moisture content were performed. The results of SEM analysis showed substantial changes in the soil structure after the addition of lime. The primary structure was porous and granular that was changed to a uniform and solid after the lime was added. According to XRD results, dominant mineral in none stabilized soil and stabilized soil are Illite and calcite, respectively. The pozzolanic reaction resulted in the reduction of clay minerals in the stabilized samples and calcite was known as the soil hardener material that led to an increase in soil strength. An increase in the hydrated lime leads to a decrease in their maximum dry unit weight and an increase in their optimum moisture content. Furthermore, increasing the hydrated lime content enhanced the Unconfined Compressive Strength (UCS) and soil's optimum moisture. An increase in the strength is significantly affected by the curing time and hydrated lime contents, as the maximum compressive strength is achieved at 7% hydrated lime. Moreover, the maximum increase in the California Bearing Ratio (CBR) achieved in clay soils mixed with 8% hydrated lime.

• International Journal of Aeronautical and Space Sciences
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• 제13권3호
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• pp.386-397
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• 2012

The stability and structure of bluff-body stabilized hydrogen flames were investigated numerically and experimentally. The velocity of coflowing air was varied from subsonic velocity to a supersonic velocity of Mach 1.8. OH PLIF images and Schlieren images were used for analysis. Flame regimes were used to classify the characteristic flame modes according to the variation of the fuel-air velocity ratio, into jet-like flame, central-jet-dominated flame, and recirculation zone flame. Stability curves were drawn to find the blowout regimes and to show the improvement in flame stability with increasing lip thickness of the fuel tube, which acts as a bluff-body. These curves collapse to a single line when the blowout curves are normalized by the size of the bluff-body. The variation of flame length with the increase in air flow rate was also investigated. In the subsonic coflow condition, the flame length decreased significantly, but in the supersonic coflow condition, the flame length increased slowly and finally reached a near-constant value. This phenomenon is attributed to the air-entrainment of subsonic flow and the compressibility effect of supersonic flow. The closed-tip recirculation zone flames in supersonic coflow had a reacting core in the partially premixed zone, where the fuel jet lost its momentum due to the high-pressure zone and followed the recirculation zone; this behavior resulted in the long characteristic time for the fuel-air mixing.

• 한국세라믹학회지
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• 제32권1호
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• pp.95-105
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• 1995

Ceria(CeO2) stabilized zirconia(CeSZ) sol was synthesized with zirconium n-butoxide Zr(OC4H9)4 and cerium nitrate hexahydrate Ce(NO3)3.6H2O as precursors and ethylacetoacetate(EAcAc) as a chelating agent under atmosphere. CeSZ films were deposited on AISI 304 stainless steel using the prepared polymeric sol by dipcoating and the coating characteristics were investigated by XRD, ellipsometry, scratch test and SEM. The CeSZ film began to crystallize from amorphous to tetragonal phase at 40$0^{\circ}C$ and it was not converted into monoclinic phase up to 100$0^{\circ}C$ by the addition of 16mol% CeO2 as a stabilizer which could suppress phase transformation of zirconia. The CeSZ films were prepared by varying the EAcAc contents and the cncentration of CeSZ sol and measured the thickness and refractive index. From these results, it was found that the EAcAc contents and concentration of CeSZ coating sol evidently affect the densification of CeSZ film. The CeSZ film coated with 0.4M CeSZ sol and heat-treated at $600^{\circ}C$ for 10min had thickness of 50nm and 17% porosity. The CeSZ film on 304 stainless steel effectively acted as a protective layer against oxidation up to 80$0^{\circ}C$ and had superior corrosion resistance in 25% H2SO4 solution for 4.5 hrs.