• Title/Summary/Keyword: Physicochemical properties

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Effect of γ-Irradiation on the Physicochemical Properties of Zein Films

  • Lee, Sehee;Lee, Myoungsuk;Song, Kyung-Bin
    • Preventive Nutrition and Food Science
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    • v.8 no.4
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    • pp.343-348
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    • 2003
  • To elucidate the effect of gamma-irradiation on the physicochemical properties of zein films, the molecular and mechanical properties of the films were examined after irradiation at various irradiation doses. Gamma-irradiation of zein solutions caused the disruption of the ordered structure of the zein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains based on an SDS-PAGE study. Gamma-irradiation increased the solubility of zein and decreased the viscosity due to cleavage of the polypeptide chains. Protein solubility of the zein films in urea/2-mercaptoethanol also increased with increasing irradiation doses. Alterations of the zein molecules by irradiation decreased water vapor per-meability by 12% and increased the elongation of zein films. However, mean tensile strength of the zein films was decreased by gamma-irradiation treatment. Measurement of Hunter color values indicated that irradiation caused a destructive effect on yellow pigments, resulting in a significant decrease in Hunter b values. The microstructure as observed by scanning electron microscopy showed that irradiated zein film had a smoother and glossier surface than the non-irradiated films.

Physicochemical and Microbial Properties of the Korean Traditional Rice Wine, Makgeolli, Supplemented with Banana during Fermentation

  • Kim, Eunkyung;Chang, Yoon Hyuk;Ko, Jae Youn;Jeong, Yoonhwa
    • Preventive Nutrition and Food Science
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    • v.18 no.3
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    • pp.203-209
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    • 2013
  • The objective of the present study was to evaluate the physicochemical and microbial properties of the Korean traditional rice wine Makgeolli, supplemented with banana during 6 day fermentation. The alcohol contents of the control and banana Makgeolli were 17.0 and 16.5%, respectively. The pH values decreased while total acidity, total soluble solids, and color values increased throughout the fermentation process. An increase in microorganism counts throughout the 6-day fermentation period was noted in all samples. The major free sugar and organic acid detected in all samples were glucose and succinic acid, respectively. There were 39 volatile compounds detected in the control and banana Makgeolli. The major ester detected was ethyl acetate (20.037 and 22.604% for the control and banana Makgeolli, respectively). The major alcohol compounds detected were 3-methylbutanol (20.933%) and 3-methyl-1-butanol (34.325%) in the control. 2-mtehyl-1-propanol (22.289%) and 3-methyl-1-butanol (39.851%) were the highest alcohol compounds detected in the banana Makgeolli.

ROLE OF SOILS IN THE DISPOSAL OF NUCLEAR WASTE

  • Lee, S.Y.
    • Korean Journal of Soil Science and Fertilizer
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    • v.19 no.3
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    • pp.251-268
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    • 1986
  • Selecting a site for the safe disposal of radioactive waste requires the evaluation of a wide range of geologic, mineralogic, hydrologic, and physicochemical properties. Although highly diverse, these properties are in fact interrelated. Site requirements are also diverse because they are influenced by the nature of the radionuclides in the waste, for example, their half-lives, specific energy, and chemistry. A fundamental consideration in site selection is the mineralogy of the host rock, and one of the most ubiquitous mineral groups is clay minerals. Clays and clay minerals as in situ lithologic components and engineered barriers may playa significant role in retarding the migration of radionuclides. Their high sorptivity, longevity (stability), low permeability, and other physical factors should make them a very effective retainer of most radionuclides in nuclear wastes. There are, however, some unanswered questions. For example, how will their longevity and physicochemical properties be influenced by such factors as radionuclide concentration, radiation intensity, elevated temperatures, changes in redox condition, pH, and formation fluids for extended periods of time? Understanding of mechanisms affecting clay mineral-radionuclide interactions under prevailing geochemical conditions is important; however, the utilization of experimental geochemical information related to physicochemical properties of clays and clay-bearing materials with geohydrologic models presents a uniquely challenging problem in that many assessments have to be based on model predictions rather than on experiments. These are high-priority research investigations that need to be addressed before complete reliance for disposal area performance is made on clays and clay minerals.

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Effect of Different Brine Injection Levels on the Drying Characteristics and Physicochemical Properties of Beef Jerky

  • Kim, Dong Hyun;Shin, Dong-Min;Lee, Jung Hoon;Kim, Yea Ji;Han, Sung Gu
    • Food Science of Animal Resources
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    • v.42 no.1
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    • pp.98-110
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    • 2022
  • Meat jerky is a type of meat snack with a long shelf life, light weight, and unique sensory properties. However, meat jerky requires a long manufacturing time, resulting in high energy consumption. In this study, beef jerky was prepared by injecting different concentrations of brine at different hot-air drying times (0-800 min). When the brine injection levels were increased to 30%, the drying characteristics of beef jerky, such as drying time and effective moisture diffusivity, were significantly improved owing to the relatively high water content and the formation of porous structures. The physicochemical properties (e.g. meat color, porosity, shear force, and volatile basic nitrogen) of the beef jerky injected with 30% brine were improved owing to the shortened drying time. Scanning electron microscopy images showed that the beef jerky structure became porous and irregular during the brine injection process. Our novel processing technique for manufacturing beef jerky leads to improved quality characteristics and shortened drying times.

Physicochemical characterization of porcine bone-derived grafting material and comparison with bovine xenografts for dental applications

  • Lee, Jung Heon;Yi, Gyu Sung;Lee, Jin Woong;Kim, Deug Joong
    • Journal of Periodontal and Implant Science
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    • v.47 no.6
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    • pp.388-401
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    • 2017
  • Purpose: The physicochemical properties of a xenograft are very important because they strongly influence the bone regeneration capabilities of the graft material. Even though porcine xenografts have many advantages, only a few porcine xenografts are commercially available, and most of their physicochemical characteristics have yet to be reported. Thus, in this work we aimed to investigate the physicochemical characteristics of a porcine bone grafting material and compare them with those of 2 commercially available bovine xenografts to assess the potential of xenogenic porcine bone graft materials for dental applications. Methods: We used various characterization techniques, such as scanning electron microscopy, the Brunauer-Emmett-Teller adsorption method, atomic force microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, and others, to compare the physicochemical properties of xenografts of different origins. Results: The porcine bone grafting material had relatively high porosity (78.4%) and a large average specific surface area (SSA; $69.9m^2/g$), with high surface roughness (10-point average roughness, $4.47{\mu}m$) and sub-100-nm hydroxyapatite crystals on the surface. Moreover, this material presented a significant fraction of sub-100-nm pores, with negligible amounts of residual organic substances. Apart from some minor differences, the overall characteristics of the porcine bone grafting material were very similar to those of one of the bovine bone grafting material. However, many of these morphostructural properties were significantly different from the other bovine bone grafting material, which exhibited relatively smooth surface morphology with a porosity of 62.0% and an average SSA of $0.5m^2/g$. Conclusions: Considering that both bovine bone grafting materials have been successfully used in oral surgery applications in the last few decades, this work shows that the porcinederived grafting material possesses most of the key physiochemical characteristics required for its application as a highly efficient xenograft material for bone replacement.

Changes in Physicochemical Properties and Antioxidant Activities of Brown Rice (Oryza sativa L.) throughout Germination

  • Oh, Sea-Kwan;Lee, Jeong-Huei;Hwang, Hung-Goo;Lee, Dong-Hyeon;Kim, Yeon-Gyu;Lee, Jin-Hwan
    • Preventive Nutrition and Food Science
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    • v.15 no.3
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    • pp.221-228
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    • 2010
  • The objective of this research was to investigate the changes in the contents of physicochemical properties including $\gamma$-aminobutyric acid (GABA), total dietary fiber (TDF), amylose, protein, and fat content in brown rice through germination for 2 different years. Total phenolic contents and antioxidant activities of DPPH and ABTS radical scavenging capacities were also determined in different solvent extracts. For the physicochemical properties, GABA, TDF, protein, and fat content increased, whereas amylose levels decreased. Specially, GABA and TDF levels showed the greatest variations among cultivars and harvest years. Total phenolic content and antioxidant activity significantly increased. The average total phenolic content at a concentration of 0.5 mg/mL in different extract solvents occurred in this order: methanol>ethylacetate>chloroform>hexane extracts. Additionally, 'Keunnun' exhibited the highest GABA levels, highest total phenolic content, and highest antioxidant activity after germination, with increases of approximately 3.7, 2.0, and 1.9 times, respectively, compared to levels before germination. These results suggest that, because of its high physicochemical contents and strong radical scavenging activities, germinated brown rice can be used as beneficial supplement.

Fat replacement by pecan nut and oregano oil and their impact on the physicochemical properties and consumer acceptability of frankfurters

  • Orozco, Daniela;Alarcon-Rojo, Alma Delia;Chavez-Mendoza, Celia;Luna, Lorena;Carrillo-Lopez, Luis Manuel;Ronquillo, Oswaldo
    • Animal Bioscience
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    • v.34 no.10
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    • pp.1674-1683
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    • 2021
  • Objective: A study was conducted to determine the physicochemical quality and consumer acceptability of beef frankfurter-type sausages formulated with pecan nut paste and Mexican oregano oil (MO) of two varieties, Poliomintha longiflora Gray (Mexican oregano Poliomintha, MOP) or Lippia berlandieri (Mexican oregano Lippia, MOL). Methods: Frankfurters were processed under six treatment conditions: control (10.67% pork fat), MOP (control + 0.01% MOP), MOL (control + 0.01% MOL), MOP-N (control + 0.01% MOP + 6% pecan nut paste), MOL-N (control + 0.01% MOL + 6% pecan nut paste), and C-N (control + 6% pecan nut paste). The physicochemical properties and the consumer acceptability were determined. Results: The addition of MO and nut did not influence the water holding capacity, drip loss, and luminosity of frankfurters, but those ingredients increased pH and shear force (p<0.05) and decreased redness (p<0.05) of frankfurters. Frankfurters were generally well accepted by consumers. However, general acceptability of sausages decreased with the addition of MO. Control sausages showed the highest acceptability. Conclusion: The MO and pecan nut paste do not affect drastically the quality of frankfurters. These results provide evidence that partial replacement of pork fat by pecan nut in frankfurters maintain a consistent physicochemical quality and its commercialization looks promising given consumers' acceptance.

Observation of Surface Morphology and Electrical Properties of Polyurethane Polymer LB Films (폴리우레탄 고분자 LB막의 표면구조 관찰 및 전기적 특성)

  • Seo, Jeong-Yeul;Shin, Hoon-Kyu;Kwon, Young-Soo
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.50 no.8
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    • pp.371-375
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    • 2001
  • We attempted to fabricate polyurethane derivatives (PU-CN, PU-DCM) LB films by using LB method. Also, we investigated the monolayer behavior at the air-water interface by surface pressure-area (${\pi}$-A) isotherms. The surface morphologies and the physicochemical properties of LB films were investigated by atomic force microscopy(AFM) and UV-vis spectroscopy, respectively. And, the electrical properties of polyurethane derivatives LB films were investigated by using the conductivity and the dielectric constant. In the surface morphologies, physicochemical and electrical properties of polyurethane derivatives LB films, the properties is different as to the polyurethane derivatives, it is considered that this phenomena could be described by the difference of lumophore pendant which was adhered at PU main chain.

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Electrical Properties and Surface Morphology for Temperature in PU Derivatives Monolayers (PU 유도체 단분자막의 온도에 따른 전기 물성과 표면 형상 관찰)

  • Seo, Jeong-Yeul;Kim, Do-Kyun;Park, Jae-Chul;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2000.11c
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    • pp.458-460
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    • 2000
  • We attempted to fabricate polyurethane derivatives (PU-CN, PU-DCM) LB films by using LB method. Also, we investigated the monolayer behavior at the air-water interface by surface pressure-area ($\pi$-A) isotherms. And, the surface morphologies and the physicochemical properties of LB films were investigated by atomic force microscopy (AFM) and UV-vis spectroscopy, respectively. Also, the electrical properties of polyurethane derivatives LB films were investigated by using the conductivity, the dielectric constant and activation energy. In the surface morphologies, physicochemical, electrical properties of polyurethane derivatives LB films, the properties is different as to the Polyurethane derivatives, it is considered that this phenomena could be described by the difference of lumophore pendant which was adhered at PU main chain.

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Effect of ionizing radiation on mechanical and electric properties of polymer composites

  • Soh, Dae-Wha;Kovtunets, V.A.;Kupchishin, A.I.;Mun, G.A.;Nurkeeva, Z.S.;Akhmetkalieva, G.T.;Khutoryanskiy, V.V.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.588-591
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    • 2002
  • Radiation technology is an effective way for regulating polymeric materials to physicochemical and mechanical properties. The effect of radiation on mechanical and electrochemical properties of new rubber-like polymeric composite materials based on poly(vinyl ether of ethyleneglycol : PVEEG) have been studied for investigating mechanical and electric property of polymer composites applications.

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