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排序方式: 共有1175条查询结果,搜索用时 9 毫秒
71.
72.
Hanna Salminen Marina Heinonen Eric A. Decker 《Journal of the American Oil Chemists' Society》2010,87(4):419-428
The purpose of this study was to evaluate the effects of berry phenolics, in this case, black currant (Ribes nigrum) anthocyanins and raspberry (Rubus idaeus) ellagitannins, in the presence of continuous phase β-lactoglobulin (β-Lg), on the oxidative stability of Brij 35-stabilized corn oil-in-water emulsions. The extent of lipid oxidation in emulsions was measured by determining the formation of lipid hydroperoxides and hexanal, and extent of protein oxidation by monitoring the loss of tryptophan and cysteine residues in the continuous phase β-Lg. Berry phenolics at concentration levels of 20 and 50 μM were able to prevent lipid oxidation with and without β-Lg in the aqueous phase. The results show that a combination of β-Lg and berry phenolics was more efficient in inhibiting hexanal formation than either component alone. Synergistic effects on antioxidant activity toward hexanal were observed only at the 20 μM levels of berry phenolics in combination with continuous phase β-Lg. The berry phenolics were also able to inhibit the oxidation of tryptophan and cysteine residues of β-Lg. The results show that the amino acid residues were oxidized prior to the propagation of lipid oxidation. This suggests that these amino acids were able to inhibit fatty acid scission. The information gained from this study would be useful in protecting emulsion-based food products from oxidative deterioration. 相似文献
73.
Oil expression tests were conducted to evaluate the performance of a novel oil expeller designed and fabricated to operate on a 200 W solar photovoltaic (PV) power system as a sole power source. The oil press was designed to press oilseeds meal with intermediate moisture content of 12±1% (w.b.) and 0.5–2 mm particle sizes. Freshly grated coconuts and ground peanuts were used to determine the oil expression efficiency of the press. The oilseed samples were pressed for 12 min with a maximum pressure of 3.0 MPa being reached at 6 min of pressing for peanuts and 8 min of pressing for coconuts. The pressure was then held for the rest of the pressing time. The press attained an average oil expression efficiency of 73% for coconuts and 70% for peanuts. The force-vs.-deformation studies indicated that peanut press meal was compacted at a higher rate as compared to coconuts. The observation on the energy consumption indicated that there was a significant increase (P<0.05) in the specific energy requirement for both coconuts and peanuts after 6 min of pressing, which resulted from the solidification of the press cake. An average specific energy of 36.55 and 20.35 Wh/kg was recorded for peanuts and coconuts, respectively, after 12 min of pressing. 相似文献
74.
Carl-Magnus Persson Andrei Fokau Ivan Serafimovich Victor Bournos Yurii Fokov Christina Routkovskaia Hanna Kiyavitskaya Waclaw Gudowski 《Annals of Nuclear Energy》2008
A subcritical zero-power source-driven coupled core, the YALINA-Booster, has been constructed for experimental investigations of neutron kinetics of source-driven systems. In this study, the reactivity of two subcritical configurations has been determined by the area ratio method. The prompt neutron decay constants have been evaluated through slope fitting of the prompt neutron decay as well as through the pulsed Rossi-α method. It is shown that the slope fitting method and the pulsed Rossi-α method give stable results whereas the area ratio method results show spatial dependence. The reasons for the spatial spread are addressed. 相似文献
75.
76.
The North Atlantic Refinery has three 5400-hp slow-speed induction motors driving reciprocating compressors for a Hydrogen plant. All motors were rewound on-site over the period of 1998-2002, using magnetic wedges as per the original design, and the motor protection was upgraded to microprocessor-type relays. In summer 2003, during routine maintenance, it was noted that these motors suffered substantial loss of slot magnetic wedges and had to be scheduled for rewedging over 2004-2006. This paper presents failure analysis, field measurements covering heat-run test results, and motor-performance and vibration analysis before and after motor rewedging work. This paper reviews the key factors for using magnetic versus nonmagnetic wedges in these applications and techniques available to predict loss of wedges. The use of a microprocessor relay for slow-speed induction motor protection is discussed, particularly, the thermal protection feature to address the cyclic-load pattern caused by the reciprocating compressor 相似文献
77.
Hanna Tölli Sauli Kujala Katri Levonen Timo Jämsä Pekka Jalovaara 《Journal of materials science. Materials in medicine》2010,21(5):1677-1684
Bioactive glasses have been developed as scaffolds for bone tissue engineering but combination with reindeer bone protein extract has not been evaluated. We investigated the effects of bone protein extract implants (5–40 mg dosages) with bioglass (BG) carrier on the healing of rat femur defects. Bioglass implants and untreated defects served as controls. All doses of extract increased bone formation compared with the control groups, and bone union was enhanced with doses of 10 mg or more. In comparison with untreated defect, mean cross-sectional bone area at the defect site was greater when implants with BG + 15 mg of extract or bioglass alone were used, bone density at the defect site was higher in all bioglass groups with and without bone extract, and the BG + 15 mg extract dosage marginally increased bone torsional stiffness in mechanical testing. Bioglass performed well as a carrier candidate for reindeer bone protein extract. 相似文献
78.
SH Bernstein J Fay S Frankel N Christiansen MR Baer C Jacobs C Blosch R Hanna G Herzig 《Canadian Metallurgical Quarterly》1999,43(2):141-144
PURPOSE: The recombinant human interleukin-1 receptor (rhu IL-1R) is a soluble truncated form of the type 1 full-length membrane-bound receptor that binds IL-1 with identical affinity to that of the membrane form. As such, it may have clinical potential by sequestering IL-1, thereby preventing it from binding to its membrane-bound receptor and eliciting a biological effect. As IL-1 has been shown to regulate leukemic cell proliferation in an autocrine fashion, a phase I trial of rhu IL-1R was conducted in patients with relapsed and refractory acute myeloid leukemia (AML). METHODS: The study group comprised 11 patients who were sequentially treated on one of three dose levels, receiving a single intravenous (i.v.) bolus dose on day 1 followed by 13 days of daily subcutaneous (s.c.) injections with the option of an additional 14 days of treatment if a response of stable disease or better was achieved. Dose level 1 i.v. bolus 500 microg/m2, s.c. dose 250 microg/m2 per day (five patients); dose level 2 i.v. bolus 1000 microg/m2, s.c. dose 500 microg/m2 per day (three patients); dose level 3 i.v. bolus 2000 microg/m2, s.c. dose 1000 microg/m2 per day (three patients). Owing to limited drug availability, the study was designed to only examine these three dose levels. RESULTS: rhu IL-IR was well tolerated. There was no grade 3 or 4 non-hematological toxicity related to the study drug and the maximum tolerated dose was not reached. No IL-1R-blocking antibodies developed during the course of the study. Serum levels of IL-1beta, IL-6 and TNF were undetectable before, during and after rhu IL-IR administration. The terminal half-life after i.v. dosing was at least 7-12 h, and after s.c. dosing 2-4 days. Serum levels of rhu IL-1R up to 360- and 25-fold those of pretreatment levels were achieved after i.v. and s.c. dosing respectively. No patient had a complete, partial or minor response to treatment; four had stable disease and seven had progressive disease. CONCLUSIONS: rhu IL-1R therapy was safe but did not have any apparent antileukemic effect at the doses administered. 相似文献
79.
80.
Benjamin P. Thompson Stuart D. Anderson Jeffrey S. Russell Awad S. Hanna 《Canadian Metallurgical Quarterly》2002,18(3):129-137
This paper presents guidelines for implementing the construction warranty contracting method in the highway construction industry. A logical, step-by-step method for effectively applying the warranty contracting program for use in the highway construction industry is developed. Relevant issues that may present obstacles to the implementation are addressed, while the best practices, compiled from an evaluation of the current industry’s state-of-the-art practices, will assist an interested state highway agency in creating a warranty specification. In performing this research, the current use of warranty specifications among state highway agencies was examined, and an in-depth case study of the Wisconsin Department of Transportation’s warranty program was conducted. 相似文献