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121.
In this study, we investigated the electrochemical oxide nanotube formation on the Ti-35Ta-xHf alloys for dental materials. The Ti-35Ta-xHf alloys contained from 3 wt.% to 15 wt.% Hf were manufactured by arc melting furnace. The nanotube oxide layers were formed on Ti-35Ta-xHf alloy by anodic oxidation method in 1 M H3PO4 electrolytes containing 0.5 wt.% NaF and 0.8 wt.% NaF at room temperature. The surface characteristics of Ti-35Ta-xHf alloy and nanotube morphology were determined by FE-SEM, STEM, and XRD. The nano-porous surface of Ti-35Ta-xHf alloys showed in 0.5 wt% NaF solution and nanotubular surface showed in 0.8 wt% NaF solution, respectively. The highly ordered nanotube layer without regular knots was formed on the Ti-35Ta-15Hf alloy in the 0.5 wt% NaF solution compared to on Ti-35Ta-3Hf and Ti-35Ta-7Hf alloys in 0.8 wt% NaF solution. Also, the nanotube length of Ti-35Ta-xHf alloys increased as Hf content increased. 相似文献
122.
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124.
This study investigated the effects of the addition of gardenia seed, green tea, or cactus pear (Opuntia ficus-indica) to rice batter at 10% on the lipid oxidation, pigments, antioxidants, and antioxidant activity of lotus root bugak and frying oil. Lipid oxidation was evaluated based on the conjugated dienoic acid and p-anisidine values. Lipid oxidation and tocopherol degradation were significantly reduced in the gardenia seed-added bugak and frying oil, whereas the cactus pear-added bugak and frying oil showed an increase. The addition of green tea had no significant effects on the lipid oxidation of bugak and frying oil. The in vitro antioxidant activity of lotus root bugak significantly increased with the addition of gardenia seed, green tea, or cactus pear. The results suggested that green tea and gardenia seed could improve the health and food functionality of antioxidation for lotus root bugak, respectively. 相似文献
125.
Effects of temperature on the autoxidation and antioxidants changes of soybean, sunflower, and olive oils were studied. The
oils were oxidized in the dark at 25, 40, 60, and 80 °C. The oil oxidation was determined by peroxide (POV) and p-anisidine values (PAV). Polyphenols and tocopherols in the oils were also monitored. The oxidation of oils increased with
the oxidation time and temperature. Induction period decreased with the oxidation temperature; 87 and 3.6 days at 25 and 60 °C,
respectively, for sunflower oil. The activation energies for the autoxidation of soybean, sunflower, and olive oils were 17.6,
19.0, and 12.5 kcal/mol, respectively. Olive oil contained polyphenols at 180.8 ppm, and tocopherols were present at 687,
290, and 104 ppm in soybean, sunflower, and olive oils, respectively. Antioxidants were degraded during the oil autoxidation
and the degradation rates increased with the oxidation temperature of oils; for tocopherols, 2.1 × 10−3 and 8.9 × 10−2%/day at 25 and 60 °C, respectively, in soybean oil. 相似文献
126.
Pig skin and wheat fiber mixture (PSFM) were assessed as fat replacers in frankfurter-type sausages. The addition of PSFM increased the moisture and protein content in the sausage because of the water binding capacity in wheat fiber and protein content in pig skin. The sausage sample containing 20% PSFM had 50% less fat, 32% fewer calories, and showed 39.5% less cooking loss than those of the control (p < 0.05). High PSFM content resulted in more stable meat emulsions and increased hardness, cohesiveness, gumminess, and chewiness. No significant differences were observed in color, flavor, tenderness, juiciness, warm-off flavor, and overall acceptability between the control and sausage sample with PSFM by the sensory panel. Therefore, PSFM could be used as fat replacers to obtain lower calories, and higher moisture, protein contents, and emulsion stability than in low-fat frankfurter-type sausages without PSFM. 相似文献
127.
Lipid oxidation and antioxidant degradation in dried laver (Porphyra) were determined during storage at water activities (Aw) of 0.11, 0.30, 0.51, 0.75, or 0.89 in the dark at 40 °C for 15 d. Lipid oxidation was evaluated by measuring peroxide value (POV) and conjugated dienoic acid (CDA) contents, and fatty acid composition was analyzed by gas chromatography. Contents of polyphenols, tocopherols, and porphyran were determined by spectrophotometry, HPLC, and gravimetry, respectively. The POV and CDA contents of the dried laver lipids increased during storage as Aw increased from 0.11 to 0.30, 0.51, 0.75, and 0.89, whereas the relative content of eicosapentaenoic acid was decreased; however, the contents of polyphenols, α‐tocopherol, and porphyran in dried laver showed the reverse phenomena. Lipid oxidation and antioxidant degradation in dried laver sharply increased at an Aw of 0.51. Polyphenols, α‐tocopherol, and porphyran contributed to reduction of lipid oxidation in dried laver. The degree of lipid oxidation of dried laver was more dependent on the concentration of α‐tocopherol than that of either polyphenols or porphyran during storage in the dark. The results strongly suggest that the quality of dried laver can be improved by preserving tocopherols as much as possible while decreasing Aw during storage. 相似文献
128.
Soojung Oh Malshick Shin Kyungae Lee Eunok Choe 《Food science and biotechnology》2013,22(6):1523-1529
Degradation of chlorophyll, carotenoids, and phycobilins in dried laver (Porphyra) was studied during storage at water activities (Aw) of 0.112, 0.316, 0.484, 0.747, or 0.890 in the dark at 40°C for 15 days. The chlorophyll, carotenoid, and phycobilin contents were determined using HPLC and spectrophotometry. The chorophyll a, carotenoid, and phycobilin contents in dried laver decreased with storage time in the dark, and degradation was increased and accelerated as the Aw value increased. Among pigments, chlorophyll a was degraded at the highest rate, and differences in degradation rates among pigments became greater as the Aw value increased. Phycoerythrin was more stable than phycocyanin. Changes in the Aw value affected degradation of phycocyanin and chlorophyll more than phycoerythrin or carotenoids. Control of the Aw value can improve the color stability of dried laver in the dark. 相似文献
129.
Stability of meoru (Vitis coignetiea) anthocyanins during heating under singlet oxygen to simulate low sugar meoru jam-making was studied. Samples consisted of meoru juice, sugars (sucrose, glucose, or fructose), and pectin were placed at 10 or 90°C under singlet oxygen which was produced with riboflavin under 5,500 lx. Anthocyanins present in samples were malvidin-3,5-diglucoside, delphinidin-3-glucoside, cyanidin-3,5-diglucoside, malvidin-3-glucoside, and cyanidin-3-glucoside in a decreasing order. Meoru anthocyanins were degraded under singlet oxygen and heating accelerated the degradation. Degradation was faster in monoglucoside anthocyanins than diglucoside anthocyanins, and in samples added with sucrose or fructose than in samples with glucose. Sucrose in samples was hydrolyzed to glucose and fructose possibly by acid present in meoru, at higher rate at 90°C than at 10°C. Simple sugars added or produced by hydrolysis of sucrose were stable during heating or at 10°C under singlet oxygen, possibly due to quenching activity of meoru anthocyanins on singlet oxygen. 相似文献
130.