• 제목/요약/키워드: moisture stability

검색결과 508건 처리시간 0.033초

무시멘트 상온 재활용 아스팔트 기층의 현장 적용성을 통한 양생기간에 관한 연구 (Study of the Curing Time of Cementless Cold Central Plant Recycled Asphalt Base-Layer through Field-Application Review)

  • 최준성;정철호;이찬희;임인수
    • 한국도로학회논문집
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    • 제19권2호
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    • pp.67-74
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    • 2017
  • PURPOSES : The objective of this study is to ascertain the curing period of cementless cold central plant recycled asphalt base-layer, using mechanical analyses and specimen quality tests on the field. METHODS : Cold central plant recycled asphalt base-layer mixture was produced in the plant from reclaimed asphalt, natural aggregate, filler for the cold mix, and the modified emulsion AP using asphalt mix design and plant mix design. In order to examine the applicability of the curing period during the field test, the international standards for the possibility of core extraction and the degree of compaction and LFWD deflection were analyzed. Moreover, Marshall stability test, porosity test, and indirect tensile strength test were performed on the specimens of asphalt mix and plant mix design. RESULTS : The plant production process and compaction method of cementless cold central plant recycled asphalt base-layer were established, and the applicability of the optical moisture content for producing the mixture was verified through the field test. In addition, it was determined that the core extraction method of the conventional international curing standard was insufficient to ensure performance, and the LFWD test demonstrated that the deflection converges after a two-day curing. However, the back-calculation analysis reveals that a three-day curing is satisfactory, resulting in a general level of performance of dense asphalt base-layer. Moreover, from the result of the specimen quality test of the asphalt mix design and plant mix design according to the curing period, it was determined that the qualities satisfied both domestic and international standards, after a two-day curing. However, it was determined that the strength and stiffness after three-day curing are higher than those after a two-day curing by approximately 3.5 % and 20 %, respectively. CONCLUSIONS:A three-day curing period is proposed for the cementless cold central plant recycled asphalt base-layer; this curing period can be demonstrated to retain the modulus of asphalt-base layer in the field and ensure stable quality characteristics.

Thickness Effect of ZnO Electron Transport Layers in Inverted Organic Solar Cells

  • Jang, Woong-Joo;Cho, Hyung-Koun
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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    • pp.377-377
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    • 2011
  • Organic solar cells (OSCs) with low cost have been studied to apply on flexible substrate by solution process in low temperature [1]. In previous researches, conventional organic solar cell was composed of metal oxide anode, buffer layer such as PEDOT:PSS, photoactive layer, and metal cathode with low work function. In this structure, indium tin oxide (ITO) and Al was generally used as metal oxide anode and metal cathode, respectively. However, they showed poor reliability, because PEDOT:PSS was sensitive to moisture and air, and the low work function metal cathode was easily oxidized to air, resulting in decreased efficiency in half per day [2]. Inverted organic solar cells (IOSCs) using high work function metal and buffer layer replacing the PEDOT:PSS have focused as a solution in conventional organic solar cell. On the contrary to conventional OSCs, ZnO and TiO2 are required to be used as a buffer layer, since the ITO in IOSC is used as cathode to collect electrons and block holes. The ZnO is expected to be excellent electron transport layer (ETL), because the ZnO has the advantages of high electron mobility, stability in air, easy fabrication at room temperature, and UV absorption. In this study, the IOSCs based on poly [N-900-hepta-decanyl-2,7-carbazole-alt-5,5-(40,70-di-2-thienyl-20,10,30-benzothiadiazole)] (PCDTBT) : [6,6]-phenyl C71 butyric acid methyl ester (PC70BM) were fabricated with the ZnO electron-transport layer and MoO3 hole-transport layer. Thickness of the ZnO for electron-transport layer was controlled by rotation speed in spin-coating. The PCDTBT and PC70BM were mixed with a ratio of 1:2 as an active layer. As a result, the highest efficiency of 2.53% was achieved.

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미강안정화(米糠安定化)를 위한 저렴 Extruder의 개발 및 이용 (Development and Use of a Low-Cost Extruder for the Rice-Oil Stabilization)

  • 최홍식;김철진
    • 한국식품과학회지
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    • 제16권1호
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    • pp.37-40
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    • 1984
  • 국내도정공장에 간단히 부착운용할 수있는 미강안정화 처리용 저렴 Extruder (K-E3030 - 100. 처리능력 시간당 400kg)를 개발하였다. 부산된 미강을 그대로 안정화기로 처리하면 pellet형으로 성형된 안정화 미강을 얻을 수 있다. 안정화 처리온도는 원료투입속도를 조절함으로서 $95-150^{\circ}C$ 범위에서 조절이 가능하며, 이때 전력 소모량은 원료미강kg 당 0.060-0.070KWH이었다. 안정화 처리미강은 처리온도에 따라 용적밀도가 원료미강의 0.313g/cc에서 0.526-0.601g/cc로 증가하였고, 수분함량은 13.08%에서 10.41-6.03%로 감소하였다. 그리고, 처리온도가 $120^{\circ}C$이상인 경우에는 학절기의 기후 조건하에서 9 주간 저장하여도 유리 지방산의 함량이 15%를 넘지 못하였다.

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소금 고결화에 따른 강성 특성 (Stiffness Characteristics according to Salt Cementation)

  • 엄용훈;쭝꽝훙;유정동;변용훈;이종섭
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.255-264
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    • 2009
  • Soils containing vanishing materials lead changes in the microstructure of particulate media due to water inflow. Thus, dissolution renders some local unstability. As the moisture contents decease, the component of the vanished materials may affects on the cementation of paniculate materials. This cementation phenomenon has a huge influence on the stiffness, strength and stability under lower stress level. The goal of this study is to introduce the cementation effects on a compressional wave velocity, a shear wave velocity, and the resonant frequency of shear waves. The glass bead and salt water with different mole contents are used. Test results show that the changes of shear and compressional wave velocities consist of three stages. In the first region, compressional wave velocities increase and shear wave velocities decrease with a decreases in reducing water contents from 100% to 90~95%. In the second region, shear and compressional wave velocities become stable at 90~95% to 10% of the water contents. In the third region, shear and compressional wave velocities increases dramatically with a decrease in the water content due to the capillary force and cementation of salt. Furthermore, the resonant frequency of the shear waves shows similar phenomenon. Specimens prepared by glass beads and salt water are proved to be able to provide a meaningful insight in under structural behaviors of the cementation.

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새조개 처리동결 가공부산물을 이용한 페이스트 젓갈 제조 (Processing of Squeezed-Type Cockle Shell By-Product Paste)

  • 배태진;강훈이
    • 한국식품영양학회지
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    • 제10권4호
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    • pp.528-532
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    • 1997
  • 새조개 여체부의 긴발을 제외한 나머지인 가공 부산물을 식량자원으로서 효율적 이용을 위한 한 방안으로 효소분해 후 가수분해물의 물성을 개선하여 다소의 조직감을 갖는 반고형 상태의 페이스트 젓갈의 제조와 품질개선에 관하여 검토하였다. 새조개 가공부산물에 절반량의 물과 4% Protease N. P.를 첨가하여 가수분해 후 여과하여 그 여액에 4% glucose를 첨가하여 10$0^{\circ}C$에서1시간 열처리하여 풍미개선, 효소의 불활성화 및 멸균을 시켰다. 물성개량제 즉 0.5% alginic acid, 1% pectin, 0.2% agar를 병용 첨가한 제품이 대조구에 비하여 조직감 및 물성개선의 효과를 나타내었고, 10,000 rpm에서 60분간 원심분리 후에도 조직감이 파괴되지 않아 그 때의 혼합안정성은 98.1%였다. 페이스트 젓갈의 성분은 수분 함량 57.7%, 총당 함량 20.6%, 총질소함향 1,458% 및 아미노질소량 1,187mg%이었으며, 총질소중 아미노질소가 차지하는 비율은 81.4%였다.

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Formulating Reduced-fat Sausages with Quinoa or Teff Flours: Effects on Emulsion Characteristics and Product Quality

  • Ozturk-Kerimoglu, Burcu;Kavusan, Hulya Serpil;Tabak, Damla;Serdaroglu, Meltem
    • 한국축산식품학회지
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    • 제40권5호
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    • pp.710-721
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    • 2020
  • This study dealt with the use of quinoa flour (QF) or teff flour (TF) as partial beef fat replacers in the formulation of emulsion-type sausages. A control (C) group was manufactured with 20% beef fat, while the other three groups were formulated with 10% beef fat plus 5% QF (Q), 5% TF (T), and 2.5% QF+2.5% TF (QT). Water-holding capacity of the emulsions was higher in Q (81.81%), T (82.20%), and QT (84.10%) samples than in C (64.83%) samples. Total expressible fluid and expressible fat were the lowest in Q and T samples, indicating the highest emulsion stability of those groups. Incorporation of QF and TF into formulations increased moisture and carbohydrate contents while decreased fat and energy values. Besides, the use of QF was effective to increase protein and dietary fiber contents. T sausages had lower luminosity (L) and higher yellowness (b) than C sausages, whilst Q sausages did not result in significant color changes. Higher cook yield values were recorded in Q (97.96%), T (98.21%), and QT (98.15%) samples compared with C (96.44%) samples. Inclusion of QF and TF to formulation led to lower hardness and gumminess, while utilization of TF was also effective to decrease chewiness. Consequently, healthier emulsified sausages were obtained by the inclusion of QF or TF that could decrease the fat content more than 50% without sacrificing overall quality, bringing advantages by quinoa over teff for increasing nutritional value and leading minimal modifications on color and texture.

개체동결 굴(Crassostrea gigas)을 이용한 레토르트파우치 굴국의 제조 및 품질특성 (Processing and Quality Characteristics of Retort Pouched Oyster Soup from IQF Oyster Crassostrea gigas)

  • 황영숙;조준현;황석민;김상현;김병균;오광수
    • 한국수산과학회지
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    • 제49권6호
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    • pp.772-778
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    • 2016
  • To develop a value-added product from individually quick-frozen oysters Crassostrea gigas (IQFO), we prepared a retort pouched oyster soup (RPOS) from IQFOs and characterized its processing conditions and quality metrics. We found that the most appropriate manufacturing process for the RPOS consisted of half-thawing and washing raw IQF oysters, blanching, adding them to the retort pouch along with other ingredients (base soup stock, IQF oyster extract, radish, bean sprouts, garlic, and red pepper), sealing, retort sterilization ($120^{\circ}$, F0-value 10 min.), cooling, and packaging inspection. The moisture, crude protein, pH and salinity of the RPOS were 91.0%, 2.8%, 6.20 and 0.9%, respectively. The total amino acid content of the RPOS was 2,163.8 mg/100 g, and the main amino acids were glutamic acid, aspartic acid, leucine, proline, lysine and arginine. The primary inorganic ions were Na, K, S and Zn. In taste compounds, total free amino acid content was 313.4 mg/100 g, and the main free amino acids were glutamic acid, taurine, proline, hydroxyproline, aspartic acid, glycine, alanine, valine, lysine and arginine. This RPOS has good storage stability and organoleptic qualities compared with commercial retort pouched shellfish soup, and is suitable for commercialization as a value-added instant seafood soup.

동아즙을 첨가한 국수의 품질 특성 (Characteristics of Wax Gourd Juice-added Dry Noodles)

  • 홍선표;전현일;송근섭;권경순;권용주;김영수
    • 한국식품과학회지
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    • 제36권5호
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    • pp.795-799
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    • 2004
  • 동아즙을 밀가루에 25, 50, 75, 100% 농도로 첨가하여 제조한 반죽의 리올로지와 이들로부터 제조한 국수의 품질특성을 조사하였다. RVA상의 호화개시온도는 전반적으로 대조구보다 첨가구가 동아즙의 첨가량이 증가함에 따라 상승하였으며 최고점도 및 최종점도는 25% 첨가구를 제외하고는 대조구에 비해 동아즙의 첨가량에 따라 높아지는 경향을 나타내었다. 파리 노그래프상의 수분흡수율 및 반죽의 약화도는 첨가량이 증가함에 따라 증가하였으나 반죽의 형성시간과 안정성은 동아즙의 첨가량에 따라 감소하였다. 제조한 국수의 조리후의 중량, 부피, 고형분 손실량 및 수분흡수율은 모두 동아즙의 첨가량이 증가함에 따라 증가하였다. 조리한 국수의 텍스쳐 측정결과 견고성, 응집성, 검성은 동아즙의 첨가량이 증가할수록 유의적으로 증가하였으나, 탄성 및 씹힘성은 유의적인 차이를 보이지 않았다. 조리한 국수의 관능검사결과, 25 및 50% 첨가구가 모든 항목에서 가장 양호한 것으로 나타났다.

Formation of Liquid Crystal Gel with Hydrogenated Lecithin and Its Effectiveness

  • Kim In-Young;Lee Joo-Dong;Ryoo Hee-Chang;Zhoh Choon-Koo
    • 대한화장품학회지
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    • 제29권2호
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    • pp.181-191
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    • 2003
  • This study described about method that form liquid crystal gel (LCG) by main ingredient with hydrogenated lechin (HL) in OW emulsion system. Result of stability test is as following with most suitable LCG's composition. Composition of LCG is as following. To form liquid crystal, an emulsifier used $4.0\;wt\%$ of cetostearyl alcohol (CA) by $4.0\;wt\%$ of HL as a booster, Moisturizers contained $2\;wt\%$ of glycerin and $3.0\;wt\%$ of 1.3-butylene glycol (1,3-BG). Suitable emollients used $3.0\;wt\%$ of cyclomethicone, $3.0\;wt\%$ of isononyl isononanoate (ININ), $3.0\;wt\%$ of cerpric/carprylic triglycerides (CCTG), $3.0\;wt\%$ of macademia nut oil (MNO) in liquid crystal gel formation. On optimum conditions of LCG formation, the pHs were formed all well under acidity or alkalinity conditions. Considering safety of skin, PH was the most suitable $\pm61.0$ ranges. The stable hardness of LCG formation appeared best in $32\;dyne/cm^2.$ Particle of LCG is forming size of $1{\~}20\;{\mu}m$ um range, and confirmed that the most excellent LCG is formed in $1{\~}6\;{\mu}m$ range. According to result that observe shape of LCG with optical or polarization microscope, LCG could was formed, and confirmed that is forming multi-layer lamellar type structure around the LCG. Moisturizing effect measured clinical test about 20 volunteers. As a result, moisturizing effect of LCG compares to placebo cream was increased $30.6\%$. This could predicted that polyol group is appeared the actual state because is adsorbed much to round liquid crystal droplets to multi-lamellar layer's hydrophilic group. It could predicted that polyol group is vast quantity present phase that appear mixed because is adsorbed to round liquid crystal to multi-lamellar layer's hydrophilic group. This LCG formation theory may contribute greatly in cosmetics and pharmacy industry development.

Study of heavy fuel oil fly ash for use in concrete blocks and asphalt concrete mixes

  • Al-Osta, Mohammed A.;Baig, Mirza G.;Al-Malack, Muhammad H.;Al-Amoudi, Omar S. Baghabra
    • Advances in concrete construction
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    • 제4권2호
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    • pp.123-143
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    • 2016
  • Use of heavy fuel fly ash (HFFA) (diesel and cracked fuel) for power generation in Saudi Arabia has generated and accumulated large quantities of HFFA as a byproduct. In this research, HFFA is studied with the emphasis on the utilization of this waste material in concrete blocks and asphalt concrete mixes. Two types of mixes, one with low and other with high cement content, were studied for concrete blocks. Different mixes having varying percentages of HFFA (0% to 25%), as cement/sand replacement or as an additive, were studied. The performance of concrete blocks is evaluated in terms of compressive strength, water absorption, durability and environmental concerns. The results showed that blocks cannot be cast if more than 15% HFFA is used; also there is a marginal reduction in the strength of all the mixes before and after being exposed to the sulfate solution for a period of ten months. HFFA is studied in asphalt concrete mixes in two ways, as an asphalt modifier (3&5%) and as a filler (50%) replacement, the results showed an improvement in stiffness and fatigue life of mixes. However, the stability and indirect tensile strength loss were found to be high as compared to the control mix due to moisture damage, indicating a need of using antistripping agents. On environmental concerns, it was found that most of the concerned elements are within acceptable limits also it is observed that lower concentration of barium is leached out with the higher HFFA concentrations, which indicates that HFFA may work as an adsorbent for this leaching element.