• Title/Summary/Keyword: water-resistance

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Effects of Milk Protein-Gum Conjugates on The Characteristics of The Dough and Staling of Bread Made of Frozen Dough During Freeze-Thaw Cycles (우유단백질-검류 복합체 첨가가 제빵용 반죽의 물리적 특성과 식빵의 노화에 미치는 영향)

  • Yun Young;Kim Young-Ho;Kim Young-Su;Choi Sung-Hee;Eun Jong-Bang
    • Food Science and Preservation
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    • v.13 no.1
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    • pp.30-36
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    • 2006
  • Milk protein-gum conjugates were prepared by Maillard reaction and added to dough to investigate the possibile use of them as anti-staling agents in bread Four different types of conjugates were added to dough, i.e., $casein-\kappa-carrageenan$ (CK), casein-sodium alginate (CA), $whey-\kappa-carrgeenan$(WK) and whey-sodium alginate (WA). Their addition to flour increased the gelatinization temperature, water absorption and development time of the dough. Extensogram showed the increased resistance to extension of the doughs resulting from the addition of the conjugates. Moisture content of the breads decreased during storage at $5^{\circ}C$ for 4 days. The breads added with conjugates had lower extents of the decreases than non-treated degrees and maintained higher moisture content than non-treated bread after 3 freeze-thaw cycles. The storage degrees at $5^{\circ}C$ for 4 days affected the increased bread hardness, but, addition of WA conjugate decreased extents of the increases. Therefore, milk protein-gum conjugates, especially WA conjugate, contributed to retarding staling of breads

Effect of Silkpeptide on Physicochemical Properties of Bread Dough (실크펩티드 첨가한 빵반죽의 이화학적 특성)

  • Kim, Young-Ho
    • Korean Journal of Food Science and Technology
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    • v.36 no.2
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    • pp.246-254
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    • 2004
  • Physicochemical properties of bread dough added with silkpeptide were investigated. Protein content of silkpeptide was 90.83%. In amino acid analysis, glycine content was highest at 18,760.04 mg%. Alanine, serine, and tyrosine contents were much higher in silkpeptide flour than wheat flour. Mixed silkpeptide showed low lightness and redness values and high yellowness. Farinograph water absorption decreased as silkpeptide content increased. Both arrival and development times of silkpeptide-added dough were longer than those of wheat flour, As silkpeptide content increased, degree of weakness increased, Maximum viscosity of amylograph decreased gradually with addition of silkpeptide, while gelatinization temperature was not affected. Extensograph showed extensibility and resistance to extension of dough increased, while ratio of resistence to extensibility highly increased with increasing amount of silkpeptide. Silkpeptide added to bread dough showed oxidation effect, indication that it could be used as natural additive for improving bread dough quality.

Physicochemical Studies on the Hard and Soft Wheats Flours (경질(硬質) 및 연질(軟質) 밀가루의 이화학적(理化學的) 성질(性質) 연구(硏究))

  • Kim, Sung-Kih
    • Korean Journal of Food Science and Technology
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    • v.11 no.1
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    • pp.13-17
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    • 1979
  • The physicochemical properties of wheat flours were investigated for hard wheat (Bara and Kameriya varieties), semi-hard wheat (Snisen variety) and soft wheat (Ume variety). There were no sigificant differences in the proximate chemical compositions of the tested wheat fluors; however, the protein contents of them were 12.18 to 8.40 % for the hard wheat flours and 6.81 % for soft wheat flour, and gluten contents were 11.77 to 8.38 % for the hard type flours and 5.53 % for soft flour. The soft wheat flour had higher whiteness, whereas the hard wheat flours showed higher starch damage values and higher flour-water absorption than the soft wheat flour. In farinograph data, the hard wheat flours had better development time, stability and valorimeter value of doughs. There were significant differences in the extensigraph data among the tested flours, i,e, resistance to extention and the area with planimeter of doughs increased with the time and their extensibility decreased. The Bara and Kameriya wheat flours had lower maximum visicosity of amylograph than Suisen and Ume wheat flours.

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Effects of Passivation Thin Films by Spray Coatings on Properties of Flexible CIGS Solar Cells (스프레이코팅법에 의한 패시베이션 박막이 플렉시블 CIGS 태양전지의 특성에 미치는 영향)

  • Lee, Sang Hee;Park, Byung Min;Kim, Ki Hong;Chang, Young Chul;Pyee, Jaeho;Chang, Ho Jung
    • Journal of the Microelectronics and Packaging Society
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    • v.23 no.3
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    • pp.57-61
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    • 2016
  • In order to protect the solar cells from the moisture and oxygen, we evaluated the electrical and optical properties for the $Cu(In,Ga)Se_2$ (CIGS) solar cells which were prepared by the spray coating method. Generally, the EVA (ethylene-vinyl acetate) films are laminated to protect the CIGS flexible solar cells, which results in a high cost process due to complicated devices. In this study, we tried to prepare the protection layers of the flexible CIGS flexible solar cells by using spray coating method instead of conventional laminating films in order to reduce the device weight as well as the process time. The CIGS solar cells with spray coating method showed an enhanced efficiency than the before treated sample (2.77% to 2.93%) and relatively proper water vapor transmission rate of the solar cells about 62.891 gm/[$m^2-day$].

A Study on the Resistance of Stress Corrosion Cracking due to Expansion Methods for Steam Generator Tubes in Nuclear Power Plants (원전 증기발생기 전열관의 확관방법에 따른 응력부식균열 저항성 연구)

  • Kim, Young Kyu;Song, Myung Ho
    • Journal of Energy Engineering
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    • v.23 no.2
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    • pp.149-157
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    • 2014
  • The steam generator tubes of nuclear power plants have various types of corrosion failures during the plant operation. The stress corrosion cracking which occurs on the outer surface of tube is called the secondary side stress corrosion cracking and mainly occurs in the expansion-transition area of tube. The causes are the concentration of impurities by the sludge pile-up related to the geometry of its region and the residual stress by tube expansion in the process of steam generator manufacturing. Especially the directionality and sizes of residual stresses are differed according to the tube expansion methods and the direction and the frequency of tube cracks depend on their characteristics. In bases on the plant experiences, it is notified that circumferential cracks of tubes expanded with explosive expansion method are dominantly occurred compared to those of tubes done with hydraulic expansion one. Therefore in this study, according to tube expansion methods frequencies and sizes of tube cracks with specific direction are compared by means of accelerated immersion test and also the crack morphology and the specific chemicals from water-chemistry environment are observed through the fracture surface examination.

Design of a Prototype System for Graft-Taking Enhancement of Grafted Seedlings Using Artificial Lighting - Effect of air current speed on the distribution of air temperature and relative humidity in a graft-taking enhancement system (인공광을 이용한 접목표 활착촉진 시스템의 시작품 설계 - 활착촉진 시스템 내의 기온과 상대습도 분포에 미치는 기류속도의 효과)

  • 김용현
    • Journal of Biosystems Engineering
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    • v.25 no.3
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    • pp.213-220
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    • 2000
  • Grafting of fruit-bearing vegetables has been widely used to increase the resistance to soil-borne diseases, to increase the tolerance to low temperature or to soil salinity, to increase the plant vigor, and to extend the duration of economic harvest time. After grafting, it is important to control the environment around grafted seedlings for the robust joining of a scion and rootstock. Usually the shading materials and plastic films are used to keep the high relative humidity and low light intensity in greenhouse or tunnel. It is quite difficult to optimally control the environment for healing and acclimation of grafted seedlings under natural light. So the farmers or growers rely on their experience for the production of grafted seedling with high quality. If artificial light is used as a lighting source for graft-taking of grafted seedlings, the light intensity and photoperiod can be easily controlled. The purpose of this study was to develop a prototype system for the graft-taking enhancement of grafted seedlings using artificial lighting and to investigate the effect of air current speed on the distribution of air temperature and relative humidity in a graft-taking enhancement system. A prototype graft-taking system was consisted by polyurethane panels, air-conditioning unit, system controller and lighting unit. Three band fluorescent lamps (FL20SEX-D/18, Kumho Electric, Inc.) were used as a lighting source. Anemometer (Climomaster 6521, KANOMAX), T-type thermocouples and humidity sensors (CHS-UPS, TDK) were used to measure the air current speed, air temperature and relative humidity in a graft-taking system. In this system, air flow acted as a driving force for the diffusion of heat and water vapor. Air current speed, air temperature and relative humidity controlled by a programmable logic controller (UP750, Yokogawa Electric Co) and an inverter (MOSCON-G3, SAMSUNG) had an even distribution. Distribution of air temperature and relative humidity in a graft-taking enhancement system was fairly affected by air current speed. Air current speed higher than 0.1m/s was required to obtain the even distribution of environmental factors in this system. At low air current speed of 0.1m/s, the evapotranspiration rate of grafted seedlings would be suppressed and thus graft-taking would be enhanced. This system could be used to investigate the effects of air temperature, relative humidity, air current speed and light intensity on the evaportranspiration rate of grafted seedlings.

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Evaluation of Thermal Insulation and Hypothermia for Development of Life Raft (해상 구명정의 단열성능평가 및 저체온증 예측 수치해석 연구)

  • Hwang, Se-Yun;Jang, Ho-Sang;Kim, Kyung-Woo;Lee, Jang-Hyun
    • Journal of Navigation and Port Research
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    • v.39 no.6
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    • pp.485-491
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    • 2015
  • The technology review about risk of hypothermia of victim according to heat transfer characteristic of life raft and sea state can use accident correspondence of standing and sinking of ship. This study studied heat transfer characteristics required for the design of life raft and thermal insulation property analysis and evaluation methods. In addition, it is study for comprehend the risk of hypothermia and suggest analysis result that is experiment of thermal insulation property and body temperature property for decide of prediction the body temperature decline Thermal Analysis apply the finite element analysis method is comprehended the property of heat conductivity, convective effect of sea water and properties changes according to property of insulation material. it measure the heat flux with attach temperature sensor on body in order to comprehend the variation of body temperature with boarding a life raft experiment on a human body. This study validate results by comparing variation of temperature measured from experiment on a body with variation of temperature from finite element analysis model. Also, the criteria of hypothermia was discussed through result of finite element analysis.

Box-Wilson Experimental Design-based Optimal Design Method of High Strength Self Compacting Concrete (Box-willson 실험계획법 기반 고강도 자기충전형 콘크리트의 최적설계방법)

  • Do, Jeong-Yun;Kim, Doo-Kie
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.19 no.5
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    • pp.92-103
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    • 2015
  • Box-Wilson experimental design method, known as central composite design, is the design of any information-gathering exercises where variation is present. This method was devised to gather as much data as possible in spite of the low design cost. This method was employed to model the effect of mixing factors on several performances of 60 MPa high strength self compacting concrete and to numerically calculate the optimal mix proportion. The nonlinear relations between factors and responses of HSSCC were approximated in the form of second order polynomial equation. In order to characterize five performances like compressive strength, passing ability, segregation resistance, manufacturing cost and density depending on five factors like water-binder ratio, cement content, fine aggregate percentage, fly ash content and superplasticizer content, the experiments were made at the total 52 experimental points composed of 32 factorial points, 10 axial points and 10 center points. The study results showed that Box-Wilson experimental design was really effective in designing the experiments and analyzing the relation between factor and response.

A Study on the Durability of Thin Electric Insulation Layers Coated on Condenser Cases by Plasma Polymerization (플라즈마 중합으로 코팅된 콘덴서 케이스 전기 절연박막의 내구성에 관한 연구)

  • Kim, Kyung-Hwan;Song, Sun-Jung;Lim, Gyeong-Taek;Kim, Kyung-Seok;Li, Hui-Jie;Kim, Jong-Ho;Cho, Dong-Lyun
    • Polymer(Korea)
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    • v.33 no.1
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    • pp.79-83
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    • 2009
  • Thin electric insulation layers were coated on aluminum plates and aluminum condenser cases by plasma polymerization of HMDSO+$O_2$. Electric resistances of the films were higher than 1.0 M$\Omega$ if they are thicker than 0.5 ${\mu}m$ independently of the type of films but their surface morphologies and adhesion strengths were dependent on the process conditions. Deposition rate and adhesion strength of the films were dependent on $O_2$/HMDSO flow ratio and discharge power. The best result was obtained at $O_2$/HMDSO flow ratio of 4 and discharge power of 60 W. Adhesion strength could also be highly improved if aluminum was pre-treated in boiling water for 30 min through the formation of Al-O-Si bonding between the film and the aluminum surface. The coated films showed excellent chemical and thermal resistances.

Deterioration of Agronomic Characteristics of Drought-Resistant GM Rice (CaMsrB2-8) (가뭄저항성 GM벼(CaMsrB2-8)의 농업적 특성의 퇴화 가능성 검정)

  • Kim, Bo-Ra;Son, Jin-Hwan;Kim, Hye-Ryun;Ham, Jung-Kwan;Dhungana, Sanjeev Kumar;Park, Soon-Ki;Shin, Dong-Hyun
    • Weed & Turfgrass Science
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    • v.2 no.2
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    • pp.159-163
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    • 2013
  • The purpose of this study is to observe the growth habit and investigate a possibility of cultivating the GM rice (CaMsrB2-8) as a rice cultivar having drought resistance. Germination viability test showed that there was no significant difference between the drought-resistant GM(CaMsrB2-8) and non-GM (Ilmi) rice which was the parent variety at the GM rice. All the seeds of CaMsrB2-8 and Ilmi germinated after 6 days. Viviparous germination was not found in CaMsrB2-8 and Ilmi that was grown in greenhouse at $23{\pm}2^{\circ}C$ with water spraying for 40 days. Ratooning of CaMsrB2-8 and Ilmi was observed in 7-14 days and found uniform in field condition. CaMsrB2-8 seemed to grow faster than Ilmi. But CaMsrB2-8 and Ilmi were similar in 14-21 days. Both CaMsrB2-8 and Ilmi showed low seed shattering and more than 90% grains were ripened. All the seeds scattered in the paddy soil surface were not germinated after passing the winter. This study suggests that the drought-resistant GM rice was not significantly different with the parent variety of Ilmi in many agronomic characteristics such as wildness traits.