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101.
102.
1IntroductionWhenthebehaviorofdynamicalautonomoussysterllislrlapedontothephasespace,weaskthatabeha,viorofsystemafldapointofthephasespa(fetobemutualone-to-Onecontinuouscorrespondence.FOrthenon-autonomoussystemweaskthatabehaviorofsystemtocorrespondwithonlyo… 相似文献
103.
模压全息图母版的拍摄研究 总被引:3,自引:1,他引:2
目前拍摄模压全息母版用的记录材料都是光刻胶.本文从它本身的特点(灵敏度低,浮雕型相位光栅和拍摄对象是散射物体等)出发,指出要拍摄出质量好的光刻胶母版应当注意到的问题.诸如拍摄参数的选择应同时考虑到衍射效率和信噪比、照明的均匀性问题、逆共轭光再现、消偏振、相干长度、外界振动对拍摄的影响问题.通过分析表明高质量的全息图不可能靠延长曝光时间来获得,使用相干性好的大功率激光束来拍摄,是非常有必要的. 相似文献
104.
Microcrystalline cellulose (avicel) is treated in hot-compressed aprotic solvents,sulfolane and 1,4-dioxane,using a batch-type reaction system with a molten tin bath in a range from 290 to 390℃. The corresponding densities of the solvent are 0.25-1.26 g/cm3 and 0.21-1.03 g/cm3 for sulfolane and 1,4-dioxane,respectively. As a result,in both solvents,more than 90% of cellulose is found to be de-composed to the solvent-soluble portion in which levoglucosan is the main component with the high-est yield of about 35% on original cellulose basis. The decomposition rate to levoglucosan is,however,faster in sulfolane than in 1,4-dioxane,while levoglucosan is more stable in 1,4-dioxane. In addition,its yield is found to be solvent-density dependent to be highest around 0.4-0.5 g/cm3 for both solvents. To elucidate these decomposition behaviors,the results obtained in this study with aprotic solvents are compared with protic solvents such as water and methanol in previous works. 相似文献
105.
风速概率分布的参数估计和置信度计算 总被引:1,自引:0,他引:1
用Weibull分布拟合风速了得了很好的效果。本文在三参数Weibull分布参数估计的基础上,讨论了其置信度问题,有助于对结论可信程度的分析。 相似文献
106.
107.
青霉素类药物拉曼散射的研究 总被引:5,自引:1,他引:4
利用显微拉曼技术对三种常见青霉素类药物做了测试和分析,得到拉曼散射谱。发现不同类青霉素的拉曼谱线有明显区别,可以用以鉴别药物。文章还给出了青霉素药物的特征峰以利区别。 相似文献
108.
L. R. Nie D. C. Mei 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(4):475-481
The properties of the underdamped Josephson junction subjected to
colored noises were investigated with large and small phase
difference (φ). For the case of the large φ, we found
numerically that: (i) the probability distribution function of
φ exhibits monostability → bistability → monostability
transitions as the autocorrelation rate (λ) of a colored
noise increases; (ii) in the bistability region the multiplicative
noise drives the phase difference to turn over periodically; (iii)
the slope K of the linear response of the junction potential
difference (〈V 〉) can be somewhat reduced by means of tuning an
optimal λ; (iv) the amplitude of φ in response to
external sinusoidal signals changes with λ. For the case of
small φ, after deriving the analytical expressions of the
potential difference amplitude (〈V 〉max) and the K in the
presence of a dichotomous noise, we found nonmonotonic behavior of
〈V 〉max and the slope K as a function of λ. 相似文献
109.
110.
Chang-lin Chen Pin-jie Hong Shu-shan Dai Cheng-cong Zhang Xiao-yun Yang 《Reaction Kinetics and Catalysis Letters》1997,61(1):175-180
The oxidative coupling of methane over (Bi2O3)1-x(WO3)x (x=0.2, 0.3, 0.4) oxygen ion conductive oxide catalysts irradiated by microwave has been studied. Compared with a conventional
heating mode, the temperature of the catalytic bed is much lower with microwave irradiation and there is a change in selectivity
favoring the production of C2 products. 相似文献