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排序方式: 共有1499条查询结果,搜索用时 15 毫秒
991.
Hens fed diets with 0.0, 7.5, 15.0, 30.0, 60.0 and 120.0 mg supplemental α-tocopherol/kg feed produced egg yolks with 25,30,35,45,50 and 75 μg/g yolk, respectively. The correlation coefficient between dietary α-tocopherol (mg/kg diet) and egg yolk α-tocopherol (μg/g egg yolk) after 28 days feeding was 0.99. The supplemented dietary α-tocopherol had an effect on the α-tocopherol in egg yolk (p<0.05). The oxidative stability of yolk was determined by measuring the oxygen and volatile compounds in the headspace of bottled yolk. α-Tocopherol had an effect on the stability of yolk as an antioxidant at 25, 45 and 50 μg/g yolk and a prooxidant at 75 μg/g or above (p<0.05). The addition of 60.0 mg α-tocopherol/kg diet resulted in the best egg yolk stability. The correlation coefficient between headspace oxygen disappearance and volatile compound formation in the headspace of bottled egg yolk was 0.84. 相似文献
992.
993.
<正>A patch antenna and our proposed metamaterial patch antenna are simulated and compared. A high gain patch antenna using a single layer metamaterial superstrate with a near to zero refractive index(n)is proposed.The simulation results provide that the gain of the proposed antenna is increased by about 7dB. Consequently,the high gain antenna can be easily obtained by using our metamaterial superstrate. 相似文献
994.
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
995.
Y2O3-doped ZrO2 (YZ) thin films were prepared on alumina substrates by the dip-coating process. The dip-coating solution consisted of a homogeneous
sol, and was prepared by using the respective chlorides as raw materials, with ethylene glycol, 2-butanol and distilled water
as solvents. The thin films containing 0–20 mol % Y2O3 were successfully produced by thermal treatment above 600 °C. The characterization for the film preparation was performed
by means of thermogravimetric–differential thermal analysis for the thermal analysis, and scanning electron microscopy for
the morphological analysis and thickness measurements. The properties of the films were characterized in terms of a study
of the crystalline phase, the crystallite size, the microstructure and the electrical conductivity by using X-ray diffraction,
scanning electron microscopy and the complex impedance techniques. In all YZ thin films, the tetragonal phase was stable at
low temperatures as a result of the crystallite size effect. However, at higher temperatures, the tetragonal phase was transformed
into either the monoclinic phase or the cubic phase, depending on the doping concentration. The YZ thin film of 8 mol% Y2O3 content was stabilized to almost cubic phase at 1000 °C. Resonable conductivity behaviour at YZ was observed for the YZ thin
films. The electrical conductivity of YZ thin films was similar to the values of the sintered body.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
996.
Sorghum distillery residue (SDR) has antioxidant and blood thinning effect on fish fed during winter, but inhibited their growth. The objective of this study was to eliminate the adverse effect but to maintain the nutraceutical benefits of SDR. The content of tannin in SDR was found to be 3.3 mg/g on dry weight basis. An in vitro digestibility test was developed to simulate the in vivo digestion of grey mullet. The protein digestibility of SDR was 47% lower than that of the control. Inhibition of trypsin activity correlated with the amount of SDR extract (r = 0.98) and decreased significantly (P < 0.05) when the SDR extract was pretreated with polyethylene glycol (PEG), a tannin binding agent. Based on Lineweaver‐Burk plot analysis, the inhibition of SDR on trypsin was of noncompetitive mixed type with changes in both Vmax and Km. A detannin treatment with PEG was tested. This treatment may provide an example to utilize other plant protein sources rich in tannin as fish feed ingredients. 相似文献
997.
为测量火灾实验的结果,必须研究导致火灾发生发展到出现轰燃的主要材料间的关系。文章提出,轰燃发生是由于可燃化学成分出现了快速分解所致。 相似文献
998.
999.
Singlet Oxygen and Ascorbic Acid Effects on Dimethyl Disulfide and Off-Flavor in Skim Milk Exposed to Light 总被引:2,自引:0,他引:2
The light-induced off-flavor and dimethyl disulfide increased as fluorescent light exposure increased from 0,2,4,6, to 8h (p<0.05). Sensory evaluation and identified compounds suggest that dimethyl disulfide was mainly responsible for the light-induced off-flavor in skim milk. Dimethyl disulfide was formed by the singlet oxygen oxidation of methionine in milk. Gas chromatographic analysis and sensory evaluation showed that 200,500, and 1000 ppm ascorbic acid, which is a singlet oxygen quencher, lowered the formation of dimethyl disulfide and off-flavor in skim milk (p<0.05). 相似文献
1000.
The personalization in knowledge portals and knowledge management systems is mainly performed based on users' explicitly specified categories and keywords. The explicit specification approach requires users' participation to start personalization services, and has limitation to adapt changes of users' preference. This paper suggests two implicit personalization approaches: automatic user category assignment method and automatic keyword profile generation method. The performances of the implicit personalization approaches are compared with traditional personalization approach using an Internet news site experiment. The result of the experiment shows that the suggested personalization approaches provide sufficient recommendation effectiveness with lessening users'unwanted involvement in personalization process. 相似文献