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The Effect of processing on the content and composition of free sterols and sterol esters in soybean oil 总被引:1,自引:0,他引:1
The content and composition of free sterols and sterol esters in crude soybean oil and in oils from different stages of two
continuous refining systems were determined. The sterols were isolated by preparative thin layer chromatography and analyzed
by gas chromatography with cholesterol as an internal standard. The free sterols in one of the degummed oils amounted to 3.1
mg/g and were diminished to 1.8 mg/g oil by the De Laval Short-Mix refining process. The content of free sterols of the other
degummed oil was reduced from 3.4 to 1.6 mg/g oil by the Zenith process. The greatest reduction of sterol content was caused
by the treatment with bleaching earth. The sterol esters accounted for 0.6 mg/g of the degummed oil, and only very small changes
were observed during the processes. However, changes in the composition of fatty acids of the sterol esters were found. These
changes might indicate a selective deacylation of sterol esters or an interesterification during the refining processes. The
composition of sterols in free and esterified form were different. Campesterol, stigmasterol and sitosterol were obtained
in both free and esterified form, but Δ7 stigmasterol was only found in esterified form. Only small changes in the percentage
distribution of the sterols occurred during the processes.
Present adress Food Technology Division, ALFA-LAVAL,S-14700 Tumba, Sweden 相似文献
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L. Ingemarsson K. Hellström L.G. Johansson J.E. Svensson M. Halvarsson 《Intermetallics》2011,19(9):1319-1329
The oxidation of a Mo(Si,Al)2 composite is investigated at 1500 °C in dry air using exposure times from 1 to 1000 h. Cross sections are examined with Scanning Electron Microscopy (SEM) and the phase composition is analyzed by X-ray diffraction (XRD). The material forms a continuous and protective alumina layer, the growth of the alumina layer following parabolic kinetics. Immediately below the scale Mo(Si,Al)2 is replaced by a Mo5(Si,Al)3 layer due to the flux of aluminum to the scale. The Al concentration in the Mo(Si,Al)2 phase in the underlying substrate decreases from 27% before exposure to 16–17% after 1000 h. The continuous alumina layer becomes covered by a top layer consisting of alumina grains embedded in a viscous melt with approximate composition 7 Na2O–15 Al2O3–78 SiO2. With time, sodium is volatilized from the melt and the top scale layer transforms to a mixture of alumina, mullite and silica melt. 相似文献
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Unannounced evacuation experiments in a cinema theatre were analysed. The analysis focused on investigating if people are influenced by others during the initial phase of a fire evacuation. This type of influence is called social influence. Three separate behaviour types were identified and studied and the recognition and pre-movement time was measured. The results suggest that social influence is an important factor and that it becomes more important when the fire cue, e.g., the alarm, is unclear or uninformative. Results also indicate that social influence increases with decreasing distance between visitors. This result implies that individuals are influenced more by people who are close than by people who are further away. 相似文献
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Key technologies for IMT-advanced mobile communication systems 总被引:2,自引:0,他引:2
Wijting C. Doppler K. Kalliojarvi K. Svensson T. Sternad M. Auer G. Johansson N. Nystrom J. Olsson M. Osseiran A. Dottling M. Luo J. Lestable T. Pfletschinger S. 《Wireless Communications, IEEE》2009,16(3):76-85
WINNER is an ambitious research project aiming at identification, development, and assessment of key technologies for IMTAdvanced mobile communication systems. WINNER has devised an OFDMA-based system concept with excellent system-level performance for flexible deployments in a wide variety of operating conditions. The WINNER system provides a significant step forward from current 3G systems. Key innovations integrated into the system concept include flexible spectrum usage and relaying, adaptive advanced antenna schemes and pilot design, close to optimal link adaptation, hierarchical control signaling, and a highly flexible multiple access scheme. The end-to-end performance assessment results demonstrate that the WINNER concept meets the IMTAdvanced requirements. 相似文献
60.
Sundfeldt M Widmark M Wennerberg A Kärrholm J Johansson CB Carlsson LV 《Journal of materials science. Materials in medicine》2002,13(11):1037-1043
The addition of sodium fluoride to poly (methyl-methacrylate) (PMMA) bone cement may theoretically improve the fixation of joint replacement. This hypothesis was tested in an animal model using nine mature healthy lop-eared rabbits. A femoral prosthesis was inserted in both knees to resurface the patellofemoral articulation. The same acrylic cement, with and without sodium fluoride, was randomised between the two sides for prosthetic fixation. Two screw shaped implants machined from cured rods of either cement were also inserted bilaterally into the proximal tibia. Qualitative and quantitative histomorphometry of the bone tissue response surrounding the cement in the femur and the intact tibial implants revealed similar results regardless of sodium fluoride addition. Six weeks after surgery removal, torque did not significantly differ between the two sides. Our findings indicate that addition of sodium fluoride to PMMA has little effect on implant stability and bone remodeling in rabbits in the short-term. 相似文献