• Title/Summary/Keyword: Chemical compositions

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Studies on the Manufacture of Undaria pinnatifida Laver and It's Physicochemical Properties -II. Chemical Composition- (미역김의 제조와 이화학적 특성에 관한 연구 -제 2 보 : 미역김의 조성-)

  • Kim, Kil-Hwan;Kim, Chang-Sik
    • Korean Journal of Food Science and Technology
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    • v.15 no.3
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    • pp.277-281
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    • 1983
  • The chemical composition of Undaria pinnatifida Laver (U.P. Laver) were determind. 1. Proximate compositions of U.P. Laver were 22.1% crude protein, 1.3% crude fat, 10.2% crude ash, 66.4% N.F.E, 3 0% crude fiber and 22.8% alginic acid. 2. U.P. Laver protein was chiefly composed of glutamic acid (3.24%) and aspartic acid (2.22%) and considerable quantities of leucine (1.98%), alanine (1.56%), valine (1.32%), lysine (1.22%) and phenylalanine (1.15%). 3. The major fatty acid contents of the lipid extracted from U.P. Laver were linolenic acid (45.2%), palmitic acid (26.14%) and linoleic acid (11.27%) and the minor fatty acid were myristic acid (8.41%), oleic acid (8.11%), and stearic acid (0.87%), respectively. The saturated and unsaturated fatty acid ratio of the oil extracted from U.P. Laver was 35.42/64.58 4. The vitamin contents of U. P. Laver were $28.1{\mu}g/g$ niacin, $25.0{\mu}g/g$ vit. E, $18.8{\mu}g/g$ vit. C. The minerals were composed 1.52% calcium, 0.32% phosphorus, 0.88% magnesium, 0.49% potassium and the others were small quantities.

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Phospholipids Isolation from Squid Viscera Residues After Supercritical Carbon Dioxide Extraction (오징어 내장의 초임계 이산화탄소 추출 잔류물로부터 인지질의 분리)

  • U, Pyoung-Ook;Chun, Byung-Soo
    • Korean Chemical Engineering Research
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    • v.48 no.6
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    • pp.741-746
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    • 2010
  • Phospholipids were recovered from squid viscera residues by ethanol extraction after supercritical carbon dioxide($SCO_2$) extraction and from squid viscera was not processed $SCO_2$ by various organic solvent extraction. $SCO_2$ extraction were performed at $45^{\circ}C$ and 20 MPa for removal of non polar lipid molecules from freeze dried squid viscera sample. Phospholipids were extracted from freeze dried squid viscera sample by chloroform, hexane, methanol, and ethanol and from $SCO_2$extracted squid viscera sample by ethanol. The pH was fixed at 5.7 for all phospholipids extraction conditions. Phospholipid classes were analyzed by HPLC equipped with evaporative light scattering detector (ELSD). Phosphatidyl choline(PC) extracted by ethanol from $SCO_2$ extracted residues was higher than that of extracted by ethanol from squid viscera. But phosphatidyl ethanolamine(PE) and phosphatidic acid(PA) were extracted higher percentage in raw squid viscera. The fatty acid compositions in phospholipids extract by ethanol extract from $SCO_2$ extracted residues were analyzed by gas chromatography(GC). Docosahexanoic acid(DHA) was found in highest percentage in phospholipid extract.

Studies on the Physico-chemical Properties of Vitrified Forms of the Low- and Intermediate-level Radioactive Waste (${\cdot}$저준위 방사성폐기물 유리고화체의 물리${\cdot}$화학적 특성 연구)

  • Kim, Cheon-Woo;Park, Byoung-Chul;Kim, Hyang-Mi;Kim, Tae-Wook;Choi, Kwan-Sik;Park, Jong-Kil;Shin, Sang-Woon;Song, Myung-Jae
    • Journal of the Korean Ceramic Society
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    • v.38 no.9
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    • pp.839-845
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    • 2001
  • In order to vitrify the Ion-Exchange Resin(IER), Dry Active Waste(DAW), and borate concentrate generated from the commercial nuclear facilities, the glass formulation study based on the their compositions was performed. Two glasses named as RG-1 and DG-1 were formulated as the candidate glasses for the vitrification of hte IER and DAW, respectively. A glass named as MG-1 was also formulated as a candidate glass for the vitrification of the mixed wastes containing the IER, DAW, and borate concentrate. The process parameters, product qualities, and economics were evaluated for the candidate glasses and confirmed experimentally for the some properties. The glass viscosity and electrical conductivity as the process parameters were in the desired ranges. the product qualities such as glass density, chemical durability, phase stability, etc. were satisfactory. In case of vitrifying the wastes using our developed glass formulation study, the volume reduction factors for the IER, DAW and mixed wastes were evaluated as 21, 89 and 75, respectively.

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Physico-Chemical Characteristics of Crossbred Pigs with Carcass Grade (교잡종 돼지에서 도체등급에 따른 돈육의 이화학적 특성 변화)

  • Jin Sang-Keun;Kim Il-Suk;Song Young-Min;Hur Sun-Jin;Hah Kyung-Hee;Kim Hoi-Yun;Lyou Hyun-Jee;Ha Ji-Hee;Kim Byeong-Woo
    • Food Science of Animal Resources
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    • v.24 no.3
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    • pp.246-252
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    • 2004
  • The objective of this study was to determine the changes of physico-chemical characteristics in crossbred pigs (Korean native breed ${\times}$ Landrace breed) by carcass grade. Research was conducted on 250 pigs divided into 5 carcass grade groups. Cooking loss have significantly (p<0.05) higher in higher carcass grade. However, water content, crude fat, pH and shear force have no difference. In meat color, a* was significantly (p<0.05) higher in C and D grade, whereas A grade was lower than those of others. L* and b* did not different among the carcass grades. In fat color, A and E grade were significantly (p<0.05) higher in b* and, C was lower than those of others. Adhesiveness and Gumminess of cooked meat were significantly (p<0.05) higher when carcass grade was higher. However hardness, cohesiveness, springiness and brittleness were not different among the carcass grades. Palmitic acid was significantly (p<0.05) higher in higher carcass grades and, saturated fatty acid/unsaturated fatty acid ratio was lower, whereas other fatty acids compositions had no difference among the carcass grades.

Preparation and characterization of poly(dimethylsiloxane) foam prepared by hydrogen condensation reaction (수소 축합 반응에 의한 폴리디메틸실록산 미세 발포체의 제조 및 물성분석 연구)

  • Lee, Soo;Moon, Sung Jin
    • Journal of the Korean Applied Science and Technology
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    • v.33 no.4
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    • pp.802-812
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    • 2016
  • Silicone foam is very useful as flame resistant material for many industrial areas such as high performance gasketing, thermal shielding, vibration mounts, and press pads. A silicone foam was prepared through simultaneous crosslinking and foaming by hydrogen condensation reaction of a vinyl-containing polysiloxane (V-silicone) and a hydroxyl-containing polysiloxane (OH-silicone) with hydride containing polysiloxane (H-silicone) in the presence of platinum catalyst and imorganic filler at room temperature. This is more convenient process for silicone foam manufacturing than the conventional separated crosslinking and foaming systems. Funtionalized silicones we used in this experiment were consisted with a V-silicone containing 1,0 meq/g of vinyl groups and a viscosity of 20 Pa-s, an OH-silicone with 0.4 meq/g of hydroxyl groups and a viscosity from 50 Pa-s, and an H-silicone containing 7.5 meq/g of hydride groups and a viscosity of 0.06 Pa.s. The effects of compositions of functionalized silicones and additives, such as catalyst and filler on the structure and mechanical properties of silicone foam were studied. 0.5 wt% of Pt catalyst was enough to accelerate the foaming rate of silicone resins. The addition of OH-silicone with lower viscosity accelerates the initial foaming rate and decreases the foam density, but the addition of V-silicone with lower viscosity reduces the tensile strength as well as the elongation. The final foam density, tensile strength, and elogation of silicone foam prepared under the SF-3 condition increase maximum to $0.58g/cm^3$, $3,51kg_f/cm^2$, and 176 %, repectively. We found out the filler alumina also played an important role to improve the mechanical properties of silicone foams in our foaming system.

Electrowinning of Tungsten From Fused Bath Composed of Calcium Chloride, Calcium Oxide and Tungstic Oxide (텅그스텐의 熔融鹽電解)

  • Kim, Jae-Won;Lee, Dong-Nyung
    • Journal of the Korean Chemical Society
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    • v.10 no.1
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    • pp.32-42
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    • 1966
  • The electrolysis of tungstic oxide dissolved in the bath of calcium chloride and calcium oxide was studied to produce metallic tungsten using carbon as anode and iron as cathode in the temperature range of 900^{\circ}$ to $1200^{\circ}C$. The binary phase diagrams $CaCl_2$-CaO and $CaCl_2-CaWO_4$ systems were constructed to determine the suitability of bath composition and the range of temperatures for the electrolysis. As $WO_3$ reacted with $CaCl_2$ to form oxychloride in the fused salt, the addition of the proper amount of CaO was necessary to avoid the loss of $WO_3$. The optimum compositions of fused bath were $CaCl_2$ 100 parts, CaO and $WO_3$ each 10 to 20 parts, with the CaO, $WO_3$ ratio greater than unity, to keep freezing point low and to prevent the vaporization of $CaCl_2$. The observed decomposition voltage at which $WO_3$ decomposes to W and CO was-0.1 volt, whereas the calculated was -0.3 volt. Metallic tungsten deposited at the cathode reacted easily with CO formed secondarily at the anode surface, to form WC below $1050^{\circ}C$, so that the cell temperature should be above $1050^{\circ}C$. The effects of cathode current densities on current efficiency were minor in the range of 1 to 5 $amp/cm^2$.

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Synthesis of Cobalt Oxide Free Black Color Spinel Pigment (CoO가 첨가되지 않은 스피넬계 흑색안료의 합성)

  • Kim, Jun-Ho;Lee, Seong-Ho;Suh, Man-Chul;Lee, Byung-Ha
    • Journal of the Korean Ceramic Society
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    • v.44 no.11
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    • pp.639-644
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    • 2007
  • Spinel pigments, developing black color in high temperature glazes at oxidation or reduction atmosphere, without CoO because of its high price were synthesized by solid solution method. Ten mixed compositions consisted of NiO, MnO, $Fe_2O_3 and $Mn_2O_3$ were fired at $1250^{\circ}C$ for 1h. The resulting pigments were characterized by using XRD, FT-IR, SEM and UV-vis spectrometer. Structure of the pigments are spinel and particles' shape are spherical or cubic. Glazed tiles containing 5 wt% pigments were fired at $1260^{\circ}C$ and $1240^{\circ}C$ in reduction atmosphere. Color in glazes were analyzed by UV-vis spectrometer. Colors of NiO 0.875 MnO $0.125{\cdot}Fe_2O_3$ $0.4875{\cdot}Cr_2O_3$ $0.50{\cdot}Mn_2O_3$ 0.0125 mole% and NiO 0.875 MnO $0.125{\cdot}Fe_2O_3$ $0.3875{\cdot}Cr_2O_3$ $0.50{\cdot}Mn_2O_3$ 0.1125 mole% in lime glaze showed black in oxidation, in reduction NiO 0.875 MnO $0.125{\cdot}Fe_2O_3$ $0.4875{\cdot}Cr_2O_3$ $0.50{\cdot}Mn_2O_3$ 0.0125 mole% and NiO 0.875 MnO $0.125{\cdot}Fe_2O_3$ $0.4375{\cdot}Cr_2O_3$ $0.55{\cdot}Mn_2O_3$ 0.0125 mole% showed black. In case of lime-barium glaze, NiO 0.875 MnO $0.125{\cdot}Fe_2O_3$ $0.3875{\cdot}Cr_2O_3$ $0.50{\cdot}Mn_2O_3$ 0.1125 mole%, NiO 0.975 MnO $0.075{\cdot}Fe_2O_3$ $0.4375{\cdot}Cr_2O_3$ $0.50{\cdot}Mn_2O_3$ 0.0625 mole% and NiO 0.925 MnO $0.075{\cdot}Fe_2O_3$ $0.4375{\cdot}Cr_2O_3$ $0.50{\cdot}Mn_2O_3$ 0.0625 mole% showed black color in oxidation and NiO 0.875 MnO $0.125{\cdot}Fe_2O_3$ $0.3875{\cdot}Cr_2O_3$ $0.50{\cdot}Mn_2O_3$ 0.1125 mole%, NiO 0.925 MnO $0.075{\cdot}Fe_2O_3$ $0.4375{\cdot}Cr_2O_3$ $0.50{\cdot}Mn_2O_3$ 0.0625 mole% and NiO 0.725 MnO $0.275{\cdot}Fe_2O_3$ $0.4375{\cdot}Cr_2O_3$ $0.50{\cdot}Mn_2O_3$ 0.0625 mole% showed black one in reduction.

Alteration of Endogenous Growth Substances in Cold-moist Stratified Seeds of Ginkgo biloba L. (냉습적(冷濕積)에 따른 은행나무종자내(種子內) 생장조정물질(生長調整物質)의 변화(變化))

  • Lee, Kyong Jae;Yim, Kyong Bin
    • Journal of Korean Society of Forest Science
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    • v.38 no.1
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    • pp.1-12
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    • 1978
  • This study has intended to disclose the change of some chemical compositions of Ginkgo seeds which were acquired the treatment of cold-moist-stratification after collection. As check sample, the room-stored seeds were used. With the reasons that when the seeds not stratified were sown the delay of field germination has usually been resulted, the effectiveness of stratificaation in respect to alteration of chemical composition is to be investigated. The increase and decrease of growth promoting and inhibiting substances were investigated by means of chromatography method followed by rice seedling test or wheat coleoptile straight-growth test. The results obtained are summarized as follows; 1. In the untreated seeds, the zone of growth inhibitors on paper chromatograph were observed without regard to the tissue differences, embryo, endosperm and seedcoat. 2. Due to stratification, the amount of inhibitor has decreased in the embryo and seed coat, but growth promoters was decreased as compared with the check materials 3. The indications of results appear that each portion of the embryo, endosperm, and seedcoats of Ginkgo biloba L. contains the growth in hibitor taking part in germination dormancy. 4. It was presumed that hastening germination was influenced by decreasing of inhibitors in the embryo and seed coats rather than by increasing of promoters. 5. Gibberellin was detected at Rf 0.26 under the UV-lamp and the abscisic acid was detected at Rf 0.62, Rf 0.70, and Rf 0.78 and showed purple, gray, blue fluorescence respectively under the UV-lamp.

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Effect of the Starch Content on the Silicate Dispersion and Rheological Properties of Polypropylene/Starch/Silicate Composites (폴리프로필렌/전분/실리케이트 복합체의 실리케이트 분산 및 유변학적특성에 미치는 전분 함량의 영향)

  • Kim, Youn Cheol;Lee, Chang-Young
    • Korean Chemical Engineering Research
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    • v.46 no.1
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    • pp.106-111
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    • 2008
  • Polypropylene (PP)/corn starch master batch (starch-MB)/silicate composites with different corn starch compositions of 10, 20, 30, 40 and 50 were prepared by melt compounding at $200^{\circ}C$, using lab scale Brabender mixer. The content of silicate was fixed at 5 wt%. The composition of starch-MB in composites was confirmed by the existence of hydroxy group and peak intensity in fourier-transform-infrared (FT-IR) spectrum. The thermal properties of the PP/starch-MB/silicate composites were investigated by differential scanning calorimetry (DSC), and thermogravimetric analyzer (TGA). There was no district change in melting temperature, and TGA curve indicates a decrease in degradation temperature with the increase of starch-MB content. The silicate dispersion of the composites was measured by X-ray diffraction (XRD) and transmission electron microscope (TEM). The degree of silicate dispersion in PP/starch-MB/silicate composites depended on the content of starch-MB. There was detectable change in d-spacing and peak intensity of the composite when the content of starch-MB was higher than 20 wt%. The rheological behavior of the composites was explained by both shear thinning effect and elastic property with the starch-MB amount. These effects were remarkable when the content of starch-MB was higher than 20 wt%. These were confirmed by an oscillatory viscometer at $200^{\circ}C$.

Synthesis of Mesoporous Pt-Au Alloy Electrode by Electrodeposition Method for Direct Methanol Fuel Cell (전기화학적 증착법에 의한 직접 메탄올 연료전지(DMFC)용 메조포러스 백금-금 합금전극제조)

  • Park, Eun-Kyung;Ahn, Jae-Hoon;Kim, Young-Soo;Kim, Kyung-Hwa;Baeck, Sung-Hyeon
    • Korean Chemical Engineering Research
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    • v.46 no.4
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    • pp.727-731
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    • 2008
  • Mesoporous Pt-Au alloy films were successfully fabricated on ITO-coated glass by electrodeposition method using tri-blockcopolymer (P123) as a templating agent. The electrolyte consisted of 10 mM hydrogen hexachloroplatinate ($H_2PtCl_6$), 10 mM hydrogen tetrachloroaurate ($HAuCl_4$), and proper amount of P123. For comparison, control samples were electrodeposited without $HAuCl_4$ and P123. Film composition was determined by EDS(Energy Dispersive X-ray Spectroscopy), and the mesoporous structure was confirmed by TEM(Transmission Electron Microscopy). SEM(Scanning Electron Microscopy) was utilized to examine surface morphology, and it was observed that the addition of P123 affected the particle growth, resulting in the significant change of surface morphology. Methanol oxidation and CO oxidation were carried out to investigate electrocatalytic activities of synthesized samples. It was observed that the catalytic activity was strongly dependent on the film compositions. Compared with nonporous electrode prepared without P123 templating, mesoporous films prepared with P123 templating showed much higher catalytic activities and stability for both methanol oxidation and CO oxidation. These enhanced electrocatalytic activities were due to the high surface area and facilitated charge transfer of mesoporous films.