• Title/Summary/Keyword: ${\gamma}'$ phase

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Analysis of Volatile Flavor Compounds in Jeju Apple Mango by Using Different Extraction Methods (추출방법에 따른 제주산 애플망고의 휘발성 향기성분 분석)

  • An, Mi-Ran;Keum, Young-Soo;Lee, Si-Kyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.5
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    • pp.775-783
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    • 2015
  • This study was carried out to investigate the physicochemical properties and volatile ingredients of Jeju Apple mango subjected to different extraction methods and GC/MS. The crude protein, fat, and ash contents were $0.22{\pm}0.01$, $0.09{\pm}0.00$, and $0.27{\pm}0.02%$, respectively, and contents of free sugar increased in the order of sucrose, fructose, and glucose, whereas maltose, lactose, and galactose were not detected. The numbers of volatile flavor compounds obtained by the SE (solvent extraction), SDE (simultaneous steam distillation extraction), and SPME (solid-phase micro-extraction) methods were 51, 59, and 71, respectively. The percentages of extracted volatile flavor compounds in mango were 11.44, 15.68, and 73.54% by the SE, SDE, and SPME methods, respectively. The most abundant compounds found in Jeju Apple mango were terpenes and their derivatives, which accounted for 44.49~94.57% of total volatiles obtained. SPME method was considered to be the most effective extraction method in terms of the numbers of detected compounds and their amounts. ${\delta}$-3-Carene was identified as the dominant compound in mango, whereas ${\alpha}$-phellandrene, ${\gamma}$-terpinene, trans-${\beta}$-ocimene, ${\alpha}$-terpinolene, limonene, ${\alpha}$-pinene, and furaneol were the next important compounds.

Isolation of Functional Fatty Acid in Cosolvent Induced SFE Process (공용매가 첨가된 초임계유체 추출공정에서 기능성 지방산의 추출)

  • Lee, Seung Bum;Park, Kyung Ai;Hong, In Kwon
    • Applied Chemistry for Engineering
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    • v.10 no.3
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    • pp.438-444
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    • 1999
  • The natural full-fat rice bran is reported to contain 8.4 to 14.7 wt % Lipids, but the amount and composition of bran depend on the type of rice, quality of paddy, pretreatments to paddy such as parboiling, type of milling system employed, and the degree of polishing. These lipids are usually mixtures of several class fatty acids containing palmitic acid, linolenic acid, linoleic acid, oleic acid, stearic acid, tocopherol, squalene, etc. In this study the oil rich essential fatty acid (EFA) including squalene was extracted from the domestic brown rice bran using supercritical fluid extraction (SFE) and cosolvent induced SFE process, respectively. And the extracts were analyzed with GC-MSD. The extracted amount of rice bran oil was dependent upon the operating pressure and temperature, and the fatty acid composition of oil was varied with the reduced density (${\rho}_{\gamma}$) of supercritical carbon dioxide. About 70~80% of rice bran oil was extracted in 4hrs. The cosolvent induced SFE process shortened the total extraction time, extracted greater amount of oil than SFE process. Especially squalene which was not found in solvent extract phase was identified in SFE and cosolvent induced SFE process.

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A Study on the Preparation of Aluina & Titania Sols for Coatings (코팅용 알루미타, 티타니아솔 제조에 관한 연구)

  • Kim, Chu-Hui;Choe, Hyeong-Su;Jo, Yeong-Sang;Im, Jong-Ju
    • Korean Journal of Materials Research
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    • v.4 no.3
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    • pp.319-328
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    • 1994
  • Aluminium and titanium precursors containing $\beta$-diketonate ligands were used for the synthesis of polymeric sols of alumina and titania by sol-gel methods. To prepare polymeric sols by solgel processing, we synthesized modified precursors having chelating organic ligands. With these precursors it was found to be possible to control both hydrolysis and polycondensation reaction rates which resulted in ultrafine particles few nms of average size. The optimum molar ratio of acid to alkoxide for alumina sol was 0.3-0.4 and that of water to alkoxide &as 1. On the other hand, the corresponding ratios for titania sol were found be 0.25-0.20 and 1 respectively. Dynamic light scattering measurements indicated that the average particle size in both sols was in the order of few nms. SEM photographs were taken to observe crack-free and smooth surfaces of coated membranes after sintering at $450^{\circ}C$. Alumina coated membrane on a slide glass had about 4-4.5$\mu \textrm{m}$, thickness and titania coated one had 2-2.5$\mu \textrm{m}$, thickness. And according to TEM photographs, the grain size of titania was smaller than 30nm and that of alumina was in the range of few $\AA$s to 2nms. An X-ray diffraction study revealed that alumina was $\gamma$ phase and titania was anatase crystal.

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Lamellar Structured TaN Thin Films by UHV UBM Sputtering (초고진공 UBM 스퍼터링으로 제조된 라멜라 구조 TaN 박막의 연구)

  • Lee G. R.;Shin C. S.;Petrov I.;Greene J, E.;Lee J. J.
    • Journal of the Korean institute of surface engineering
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    • v.38 no.2
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    • pp.65-68
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    • 2005
  • The effect of crystal orientation and microstructure on the mechanical properties of $TaN_x$ was investigated. $TaN_x$ films were grown on $SiO_2$ substrates by ultrahigh vacuum unbalanced magnetron sputter deposition in mixed $Ar/N_2$ discharges at 20 mTorr (2.67 Pa) and at $350^{\circ}C$. Unlike the Ti-N system, in which TiN is the terminal phase, a large number of N-rich phases in the Ta-N system could lead to layers which had nano-sized lamella structure of coherent cubic and hexagonal phases, with a correct choice of nitrogen fraction in the sputtering mixture and ion irradiation energy during growth. The preferred orientations and the micro-structure of $TaN_x$ layers were controlled by varing incident ion energy $E_i\;(=30eV\~50eV)$ and nitrogen fractions $f_{N2}\;(=0.1\~0.15)$. $TaN_x$ layers were grown on (0002)-Ti underlayer as a crystallographic template in order to relieve the stress on the films. The structure of the $TaN_x$ film transformed from Bl-NaCl $\delta-TaN_x$ to lamellar structured Bl-NaCl $\delta-TaN_x$ + hexagonal $\varepsilon-TaN_x$ or Bl-NaCl $\delta-TaN_x$ + hexagonal $\gamma-TaN_x$ with increasing the ion energy at the same nitrogen fraction $f_{N2}$. The hardness of the films also increased by the structural change. At the nitrogen fraction of $0.1\~0.125$, the structure of the $TaN_x$ films was changed from $\delta-TaN_x\;+\;\varepsilon-TaN_x\;to\;\delta-TaN_x\;+\;\gamma-TaN_x$ with increasing the ion energy. However, at the nitrogen fraction of 0.15 the film structure did not change from $\delta-TaN_x\;+\;\varepsilon-TaN_x$ over the whole range of the applied ion energy. The hardness increased significantly from 21.1 GPa to 45.5 GPa with increasing the ion energy.

Enzymatic Synthesis of Low-trans Fats Containing Conjugated Linoleic Acids and Their Physicochemical Characteristics (Conjugated Linoleic Acid(CLA)를 함유한 기능성 저트랜스 유지의 효소적 합성 및 이화학적 특성 연구)

  • Nam, Ha-Young;Lee, Ki-Teak
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.6
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    • pp.752-760
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    • 2008
  • Scale-up production of low-trans fat containing conjugated linoleic acid (CLA-TFO) was performed through lipase-catalyzed synthesis. Blend of fully hydrogenated soybean oil, olive oil containing conjugated linoleic acid and palm oil with 1:2:7 ratio was interesterified through Lipozyme RM IM in the 1 L-batch type reactor at $65^{\circ}C$ for 12 hrs, and the physicochemical and melting properties of CLA-TFO were compared with conventional (high trans fat) or commercial low-trans fat shortening. The trans fatty acids content in the conventional shortening (48.8 area%) was much higher than that of low-trans shortening (0.4 area%) and CLA-TFO (0.3 area%+CLA; 7.6 area%). Acid, saponification and iodine values of CLA-TFO were 0.4, 173.9 and 59.0, respectively. Their ${\alpha}$-, ${\gamma}$-tocopherol contents showed 4.7, 1.0 mg/100 g. Differences were observed in the solid fat contents (SFC), melting point of the conventional or low-trans fat and CLA-TFO. Each SFC of conventional, low-trans fat and CLA-TFO was 32.0, 29.3 and 30.4% with melting point of 38.5, 43.0 and $39.5^{\circ}C$ at $35^{\circ}C$, respectively. In texture profile analysis, hardness of conventional, low-trans fat and CLA-TFO was 111.7, 75.2 and 63.8 g.

Predictive Thermodynamic Model for Gas Permeability of Gas Separation Membrane (기체 분리막의 투과 특성 예측 모델식 개발)

  • Kim, Jong Hwan;Hong, Sung Kyu;Park, Sang Jin
    • Korean Chemical Engineering Research
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    • v.45 no.6
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    • pp.619-626
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    • 2007
  • It is of special interest in our membrane separation technology due to its low energy consumption and cost, relatively simple equipment, low investment and operation cost, et al. Full scale utilization of such processes can be widely utilized to the various fields. Using the difference of permeability of gas molecules between the filter layers, it is able to separate effectually pure gases from the mixed gases. In this paper, the membranes of PDMS, ${\gamma}-radiated$ PDMS, PTFE, PTFE-X are chosen to develop the predictive model for the separation of pure gases such as oxygen, nitrogen, hydrogen, and other gases from mixed gases. By utilizing the thermodynamic gas properties($\sigma$, $\varepsilon/k$) and experimental data of gas transport characteristics for different polymer membranes, it is able to develop the predictive model equation under the influence of temperature, pressure and polymer characteristics. Predictive model developed in this research showed good agreement with experimental data of gas permeability characteristics for develop four different polymer membranes. The proposed model can also be extended to the general equation for predicting the separation of gases based on the properties of polymeric membranes.

Seismic Anisotropy Physical Modeling with Vertical Transversely Isotropic Media (VTI 매질의 탄성파 이방성 축소모형실험)

  • Ha, Young-Soo;Shin, Sung-Ryul
    • Geophysics and Geophysical Exploration
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    • v.13 no.4
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    • pp.307-314
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    • 2010
  • Although conventional seismic data processing is based on the assumption that the media are isotropic, the subsurface is often anisotropy in shale formation or carbonate with cracks and fractures. This paper presents the anisotropic parameter and seismic modeling in transversely isotropic media with a vertical symmetry axis using seismic physical modeling. The experiment was successfully carried out with VTI media, laminated bakelite material, using contact transducer of p and s-wave transmission. The variation of velocities with angle of incidence was clearly shown in anisotropic material. Comparing these velocities with the calculated phase velocities, the (P) and (S)-wave velocity observed in anisotropic material was a very good agreement with the calculated values. Anisotropic parameter ${\varepsilon}$, ${\delta}$, ${\gamma}$ was estimated by using Lame's constant calculated from the observed velocity. For the purpose of testing (S)-wave polarization, a birefringence experiment was carried out. The higher velocity was associated with the polarization parallel to the fracture, and the lower velocity was associated with the polarization perpendicular to the fracture.

Comparative Analysis of Volatile Flavor Compounds in Taiwan Apple Mango and Philippines Carabao Mango (대만 산 애플 망고와 필리핀 산 카라바오 망고의 휘발성 향기성분 분석)

  • An, Mi-Ran;Keum, Young-Soo;Lee, Si-Kyung
    • Korean Journal of Food Science and Technology
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    • v.47 no.2
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    • pp.191-197
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    • 2015
  • We investigated the physicochemical properties and volatile flavor compounds in Taiwan Apple Mango (TAM) and Philippines Carabao Mango (PCM). The volatile flavor compounds were extracted using solid-phase microextraction (SPME) and analyzed by GC/MS. TAM and PCM have significantly different chemical composition, except for their crude ash. The moisture and crude fat contents were higher in TAM, whereas the crude protein and carbohydrate contents were higher in PCM. The major free sugars in order of concentration were sucrose, fructose, and glucose. We identified 56 and 59 volatile flavor compounds in TAM and PCM, respectively. Terpenes and their derivatives comprised 94.42% of the volatile flavor compounds in TAM, but only 63.79% of those in PCM. The acidic compound contents were higher in PCM than in TAM. ${\delta}$-3-Carene was the dominant flavor compound in these two mango cultivars. ${\alpha}$-Copaene, ${\alpha}$-guaiene, germacrene D, ${\alpha}$-bulnesene, and ${\gamma}$-gurjunene were found only in TAM, whereas ${\beta}$-myrcene, ${\alpha}$-phellandrene, ${\beta}$-phellandrene, ${\alpha}$-terpinolene, and cis-3-hexenyl butyrate were identified in PCM. Based on the results, we suggest that these compounds might contribute to the distinguishing flavor properties in different varieties of mango.

Effects of Apolipoprotein A-I on Apoptosis and Cytokine Production in Human Neutrophils (인간 호중구의 세포사멸과 시토카인 분비에 대한 아포지방단백 A-I의 영향)

  • Kang, Hyung-Kon;Choi, Jae-Hyung;Huh, Jae-Taeck
    • Journal of Life Science
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    • v.21 no.1
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    • pp.22-30
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    • 2011
  • Apolipoprotein A-I (apoA-I) has anti-inflammatory and anti-oxidative properties. This study was designed to investigate whether apoA-I affects apoptosis and cytokine production of human blood neutrophils in an in vitro culture system. Spontaneous apoptosis of neutrophils was significantly delayed by apoA-I. In addition, high density lipoprotein containing apoA-I also delayed apoptosis of neutrophils. Apoptosis of neutrophils was inhibited by anti-scavenger receptor type B-I antibodies. The amounts of interleukin-8, interferon (IFN)-inducible protein 10 (IP-10), and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) in the supernatants of cultured neutrophils treated with apoA-I were significantly increased. Combined treatment of neutrophils with IFN-$\gamma$ and apoA-I produced higher amounts of IP-10 and TNF-$\alpha$ than did treatment with IFN-$\gamma$ or apoA-I alone. The present study reveals that apoA-I activates neutrophils to produce cytokines and delays spontaneous apoptosis of neutrophils. These findings suggest that apoA-I, although a well-known negative acute-phase protein, has a pro-inflammatory effect in neutrophils.

The Effect of Vandium on the microstructure and Elevated Temperature Sliding Wear Resistance of Fe-20Cr-1.7C-1Si-xV Hardfacing Alloy (Fe-20Cr-1.7C-1Si-xV 경면처리 합금의 미세조직과 고온 Sliding 마모저항성에 미치는 Vanadium의 영향)

  • Kim, Jun-Gi;Kim, Geun-Mo;Lee, Deok-Hyeon;Jang, Se-Gi;Gang, Seong-Gun;Kim, Seon-Jin
    • Korean Journal of Materials Research
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    • v.8 no.10
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    • pp.969-974
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    • 1998
  • The effect of vanadium, which is known to decrease the stacking fault energy of Fe-base alloys, on the microstructure and elevated temperature sliding wear resistance of Fe-20Cr- 1.7C- 1Si alloy was investigated. The maximum amount of vanadium maintaining the austenitic matrix seems to be about 3wt.% in Fe-20Cr- 1.7C-1Si-xV (x = 0, 1, 3, 6. lOwt.%) alloys and the austenitic alloys showed better wear resistance than ferritic alloys. It was considered to be due to the low stacking fault energy and $\gamma->\alpha$ strain-induced phase transformation at rmm temperature. It was shown from elevated temperature sliding tests up to .$225^{\circ}C$ that the addition of vanadium increases the temperature, at which the transition from oxidative wear to adhesive wear occur, and the amount of d formed at $225^{\circ}C$. Thus, it was considered that the addition of vanadium improves the elevated temperature sliding wear resistance of Fe-20Cr- 1.7C - 1Si by reducing the increasing rate of stacking fault energy with temperature and by increasing Ma temperature.

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