• Title/Summary/Keyword: 1,4-Addition

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A Study of the Foaming Poperties of Mungbean Protein Isolate (녹두 단백질의 기포특성에 관한 연구)

  • 민성희;손경희
    • Korean journal of food and cookery science
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    • v.4 no.2
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    • pp.1-9
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    • 1988
  • This study was carried out in order to study the foaming properties of mungbean protein. Mungbean protein isolate was tested for the purpose of finding out the effect of pH, addition of sucrose on foaming properties. The results were summarized as follows: 1. Foam expansion values were generally depen. dent on protein concentration to 3% protein suspension. From 1% to 3% suspension, foam expansion values increased. However over 3% suspension, the values decreased. In 1% mungbean protein suspension, the foam expansion value of suspension at pH 4.5 was greater than that of at pH9. In 3%, 5%, and 10% suspensiona the foam expansion values of suspension at pH 7 was the lowest. Foam expansion value significantly decreased by the addition of sucrose. 2. The foam stability appeared the greatest value as protein concentration increased. It appeared the greatest value at pH 4.5. When sucrose was added, the foam stability increased. The more sucrose was added, the better foam stability was.

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Thermal Properties and Water Sorption Behaviors of Epoxy and Bismaleimide Composites

  • Seo, Jong-Chul;Jang, Won-Bong;Han, Hak-Soo
    • Macromolecular Research
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    • v.15 no.1
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    • pp.10-16
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    • 2007
  • In this work, we prepared epoxy/BMI composites by using N,N'-bismaleimide-4,4'-diphenylmethane (BMI), epoxy resin (diglycidyl ether of bisphenol-A (DGEBA)), and 4,4'-diamino diphenyl methane (DDM). The thermal properties and water sorption behaviors of the epoxy and BMI composites were investigated. For the epoxy/BMI composites, the glass transition and decomposition temperatures both increased with increasing BMI addition, which indicates the effect of BMI addition on improved thermal stability. The water sorption behaviors were gravi-metrically measured as a function of humidity, temperature, and composition. The diffusion coefficient and water uptake decreased and the activation energy for water diffusion increased with increasing BMI content, indicating that the water sorption in epoxy resin, which causes reliability problems in electronic devices, can be diminished by BMI addition. The water sorption behaviors in the epoxy/BMI composites were interpreted in terms of their chemical and morphological structures.

Effects of oxygen, hydrogen and nitrogen addition in the synthesis of diamond-like carbon films (DLC 합성시 산소, 수소 및 질소 첨가의 효과)

  • 황민선;이종무
    • Journal of the Korean Vacuum Society
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    • v.8 no.2
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    • pp.165-171
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    • 1999
  • Diamond-like carbon(DLC) films were synthesized using the rf-plasma CVD technique with the addition of small amounts of nitrogen and oxygen to a gas mixture of $CH_4$ and $H_2$. The gas flow ratio of $CH_4$ to $H_2$ was 2.4:1, and 3% , 13.6% of nitrogen were added to the gas mixture of $CH_4$ and $H_2$ for the deposition of DLC films. The film stress tended to decrease as the nitrogen concentration increased from 3% to 13.6%, probably due to the decrease of the number of the interlink between carbon atoms. The residual stress tended to slightly decrease when 3% of oxygen was added. Scratch tests were performed to investigate the adhesion between the DLC films and the Ti intelayer after pretreating the TiN surface with direct hydrogen plasma. The adhesion was enhanced by adding nitrogen and oxygen to the $CH_4$ and $H_2$ gas mixture. The adhesion for the 3% nitrogen addition was better than that for the 13.6% nitrogen addition. The Vicker's hardness of the DLC films was measured to be 1100Hv.

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Effects of Soil Addition and Subsoil Plowing on the Change of Soil Chemical Properties and the Reduction of Root-Knot Nematode in Continuous Cropping Field of Oriental Melon (Cucumis melo L.) (시설참외 연작재배지 토양의 객토 및 심토반전이 토양 화학성 변화와 토양선층 억제효과에 미치는 영향)

  • Jun, Han-Sik;Park, Woo-Chul;Jung, Jae-Sik
    • Korean Journal of Environmental Agriculture
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    • v.21 no.1
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    • pp.1-6
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    • 2002
  • To elucidate the effect of soil addition and subsoil plowing on the change of sell chemical properties and the reduction of root-knot nematode, this experiment carried out in continuous cropping field of protected oriental melon (Cucumis melo L.). Soil addition reduced electric conductivity (E. C.) from 4.3 to 1.8 dS/m (58%), available $P_2O_5$ from 406 to 182 mg/kg (55%) and organic matter content from 16 to 11 g/kg (31%). Population densities of root-knot nematode in soil reduced as much as 89%, 84%, and 69% at first year, third years, and of five years later, respectively The effects of subsoil plowing were similar to that of soil addition. E. C. and phosphate were reduced from 4.30 to 1.98 dS/m (54%) and phosphate from 406 to 329 mg/kg (19%), respectively. Population densities of root-knot nematode reduced as much as 71%, 67%, and 42% after 1, 3, and 5 years, respectively Subsoil plowing reduced nematode densities only for three years.

Combined Effects of Sodium Substitution and Addition of Cellulose or Chitosan on Quality Properties of Pork Sausages

  • Jin, Sang Keun;Hur, Sun Jin;Yim, Dong Gyun
    • Food Science of Animal Resources
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    • v.39 no.4
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    • pp.555-564
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    • 2019
  • The aim of this study was to assess the impacts of cellulose/chitosan addition in combination with sodium substitution, including KCl and $MgCl_2$, on the quality and sensory properties of sausages. Sausages (control, 100% NaCl; T1, 60% NaCl, and 40% KCl; T2, 50% NaCl, 40% KCl, and 10% $MgCl_2$) were formulated with cellulose/chitosan at concentrations of 3% and compared to control. T1 and T2 decreased the pH values (p<0.05), while the use of cellulose increased these values. Biopolymer addition reduced lipid oxidation (p<0.05). In sausages containing cellulose, volatile basic nitrogen (VBN) in T1 was lower than that in T2 (p<0.05). The use of cellulose increased L*-, a*-, and W color values in T1 (p<0.05). Furthermore, cellulose addition was associated with lower hardness (p<0.05). Cellulose addition contributed to better overall acceptability (p<0.05). Consequently, a combined mixture containing T1 and cellulose appears to be the best combination, indicating a possible synergistic effect.

Physicochemical Characteristics of Yackwa with Added Rice Wine Cake (주박 첨가 약과의 이화학적 특성)

  • Cho, Eun-Ja;Yang, Mi-Ok;Kang, Hyun-Joo
    • Journal of the East Asian Society of Dietary Life
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    • v.17 no.1
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    • pp.94-102
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    • 2007
  • This study was designed to characterize the physicochemical effects of the addition of rice wine cake(0, 1, 2, 4%) to yackwa. Dietary fiber, volume, SEM, TBA, color, texture characteristics and sensory evaluation of yackwa were investigated. The dietary fiber content of rice wine cake was 10.24%, and the dietary fiber content of yackwa increased with added rice wine cake. The extensibility value increased with more rice wine cake. SEM revealed, many holes in a delicate structure with many layers. During a 4-week storage period, yackwa containing rice wine cake had lower TBA values than control, except for the sample containing 4% rice wine cake. The TBA value of yackwa containing 4% rice wine cake had the highest TBA value. The L value and b value of samples decreased with the addition of rice wine cake and storage time, but the value increased with added rice wine cake according to the storage time. The hardness, cohesiveness and gumminess of yackwa increased according to the time of storage and the addition of rice wine cake, but the springiness and chewiness of yackwa decreased. In sensory evaluations, all items received the lower scores according to the storage time. Yackwa that contained 1%(RWC1) received the highest score for color and flavor, and yackwa that contained 2% (RWC2) had the highest score for crispness and roast. Overall preference was, in order: RWC2 > RWC1 > CON > RWC4. Yackwa that contained $1{\sim}2%$ rice wine cake possessed superior features in most of the quality properties and in sensory evaluation, so yackwa that contains rice wine cake can be used as a functional food.

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PHOTOCHEMICAL REACTIONS OF AROMATIC $\alpha$-DIKETONES

  • Kim, Sung Sik
    • Journal of Photoscience
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    • v.1 no.2
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    • pp.123-126
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    • 1994
  • Irradiation of aromatic $\alpha$-diketones, such as benzil, 4,4'-dimethylbenzil, 4-chlorobenzil, 4,4'-diisopropylbenzil, 3,3,'-dimethylbenzil, in methanol gives rise to xanthone derivatives, in addition to $\alpha$-hydroxyketones. Irradiation of 4,4'-dibromobenzil, 2,2'-pyridil, 2,2'-naphthil and 9,9'-anthril yields only $\alpha$-hydroxyketones, whereas 4,4'-dimethoxybenzil yields methyl 4-methoxybenzoate.

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Effects of Glucose, Lactate and Pyruvate on Development of In Vitro Matured and Fertilized Porcine Embryos (Glucose, Lactate 및 Pyruvate가 돼지 체외수정란의 초기발생능에 미치는 영향)

  • 오건봉;박병권;서길웅;이규승
    • Korean Journal of Animal Reproduction
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    • v.19 no.1
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    • pp.9-14
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    • 1995
  • This study was conducted to investigate the effect of energy source on development of in vitro development of in vitro matured and fertilized porcine 2-cell embryos. The relative preferences of glucose, lactate and pyruvate for in vitro development of porcine 2-cell embryos were determined. The results obtained are as follows. 1. 33.3, 20.8 and 29.2% of porcine embryos reached morula stage in addition to lactate, glucose, and both glucose and lactate in the culture medium as energy source, respectively. 2. 38.5, 15.4 and 26.9% of porcine embryos reached morula stage in addition to pyruvate, glucose, and both glucose and pyruvate in culture medium as energy source, respectively. 3. 42.9, 21.4 and 28.6% of porcine embryos reached morula stage in addition to pyruvate and lactate, glucse alone, and glucose, lactate and pyruvate in culture medium as energy source, respectively.

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Toughening of Boron Carbide Ceramics by Addition of $TiB_2$ ($TiB_2$ 첨가에 의한 탄화붕소 소결체의 파괴인성 증진)

  • 이채현;박원규;김종희
    • Journal of the Korean Ceramic Society
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    • v.33 no.4
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    • pp.464-470
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    • 1996
  • Toughening mechanism of boron carbide ceramics by the addition of titanium boride was investigated. Speci-men was prepared by hot pressing of boron carbide with upto 30vol% of titanium boride particulates. Toughness of boron carbide ceramics was increased from 4.7 MPa m1/2 to 6.3 MPa m1/2 with 15 vol% TiB2 addition. But further increase of TiB2 content results in slow decrease of toughness. From microstructure evaluation and crack propagation behavior it is concluded that the major toughening mechanism is crack deflection pheno-mena.

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