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61.
The optical embedded diffraction gratings with the internal refractive index modification in BK-7 glass plates were demonstrated using low-density plasma formation excited by a high-intensity femtosecond (130 fs) Ti: sapphire laser (λp=790 nm). The refractive index modifications with diameters ranging from 400 nm to 4 μm were photoinduced after plasma formation occurred upon irradiation with peak intensities of more than 1×1013 W/cm2. The graded refractive index profile was fabricated to be a symmetric around the center of the point at which low-density plasma occurred. The maximum refractive index change (Δn) was estimated to be 1.5×10-2. Several optical embedded gratings in BK-7 glass plate were demonstrated with refractive index modification induced by the scanning of low-density plasma formation. 相似文献
62.
GMT-sheet is used in automobile bumper with high rigidity and strength, and its joining strength is influenced by lap length, one of the joined molding conditions. Fracture strength was calculated by dividing fracture load with cross-sectional area. Total five repeated measurements were made to obtain the average value. Tensile test was conducted at room temperature for 10 specimens. In addition, the effect of compression ratio on creep and tensile performance during lap joined molding was discussed. With increasing lap length, the lap joining efficiency of GMT-sheet was increased. However, higher compression ratio reduced the joining efficiency. Creep test on GMT-sheet showed abrupt fracture without tertiary creep. This can be explained by the weak thermal resistance of the resin. If GMT-sheet was exposed to high temperature for a long time, it was easily failed by external force. 相似文献
63.
Oxidation and burning behaviors were studied for CaO added AM50 Mg composites which were manufactured by conventional melting and casting processes without SF6 protective gas. CaO added AM50 Mg composites show the stable oxidation resistance, while AM50 Mg alloys show the poor oxidation resistance. The effects of CaO addition on the burning resistance under ambient, nitrogen and dry air atmospheres were examined for CaO added AM50 Mg composites. With increasing CaO addition, the burning temperature increases under ambient, nitrogen and dry air atmospheres. The burning temperatures of small test specimen under all conditions greatly increase even by 0.3% CaO (mass fraction) addition into AM50 Mg alloys. 相似文献
64.
A systematic investigation of the microstructure of CrAlCxN1-x coatings as a function of carbon contents was conducted. Quaternary CrAlCxN1-x coatings were deposited on Si wafers by a hybrid coating system combining an arc-ion plating technique and a DC reactive magnetron sputtering technique using Cr and Al targets in the Ar/N2/CH4 gaseous mixture. The effect of carbon content on microstructure of CrAlCxN1-x coatings was investigated with instrumental analyses of X-ray diffraction, X-ray photoelectron, and high-resolution transmission electron microscopy. The results show that the carbon content of CrAlCxN1-x coatings linearly increases with increasing CH4/(CH4/N2) gas flow rate ratio. The surface roughness of the CrAlCxN1-x coating layer decreases with the increase of carbon content. 相似文献
65.
66.
Synthesis of LiNiO2 cathode by the combustion method 总被引:1,自引:0,他引:1
MYOUNGYOUP SONG IKHYUN KWON HUNUK KIM SUNGBO SHIM DANIEL R. MUMM 《Journal of Applied Electrochemistry》2006,36(7):801-805
To determine optimum conditions for the synthesis of LiNiO2 by the combustion method, syntheses were carried out in air and under oxygen at various calcination temperatures and for different times. The electrochemical properties of the prepared samples were then investigated. The optimum conditions are preheating at 400 °C for 30 min in air in the mole ratio of urea to nitrate 3.6 and calcination at 750 °C for 36 h under O2. The LiNiO2 synthesized under these conditions had a first discharge capacity of 189 mAh g−1 at 0.1 C-rate and relatively good cycling performance. This sample has a larger value of I
003/I
104 (smaller cation mixing) and a smaller R-factor (larger hexagonal ordering). Cycling performance was investigated in various voltage ranges. The first discharge capacity increased as the upper limit of the voltage range rose. The first discharge capacity was small but cycling performance was good when the sample was cycled in the voltage range with the lowest upper limit. 相似文献
67.
Four anionic trypsins, tentatively labeled trypsin A, B, C, and D, isolated from crayfish hepatopancreas, had high casein activity between pH 5.5 and 10.0. Temperature optima for hydrolysis of casein were 45°C for A and B, and 50°C for C and D. Trypsin D had the highest substrate turnover number (Vmax) for casein reaction compared with the other trypsins at pH 6.8. Trypsins A and D had higher activities against myofibrilla and sarcoplasmic proteins from crayfish tail meat than did B and C. Results suggested that trypsins A and D are important in development of mushiness in crayfish tail meat compared with other trypsins present. 相似文献
68.
Characterization and Food Application of an Amperometric Needle-Type L-Lactate Sensor 总被引:1,自引:0,他引:1
There have been increasing needs for biosensing in the food industry because it is accurate, rapid and efficient. A needle-type L-lactate sensor with a three-layer membrane system which uses lactate oxidase as the biological component was prepared. The sensor had an optimum pH around 9–10 and an optimum temperature at 45 C. The current response was stable over 40 days and specifically responded to L-lactic acid. The sensor gave accurate L-lactate measurements in kimchi and yogurt of 187.4 ± 4.1 and 734.1 ± 34.5 mg/dL, similar to those of a spectrophotometric L-lactate kit. 相似文献
69.
The changes in the size and shape of soybean protein bodies in different solvent systems were observed, and their influence on hydrodynamic properties in solutions was investigated by capillary viscometer. The intrinsic viscosity of the isolated protein bodies varied with the type of dispersion media; 0.036 cm3/g in CCI4-benzene solution, 0.355 cm3/g in 50% glycerol-water mixture, 0.574 cm3/g in water at pH 7, and 1.18 cm3/g in the aqueous solution at pH 12. The hydration of the protein bodies in different dispersion media was estimated by Oncley's method and Mooney's method. The estimated degree of hydration agreed well with the swelling of the protein bodies as observed by microscope. 相似文献
70.