On account of limited knowledge of the breakup of power law liquid film, the process of its disintegration and atomization was studied by using a planar liquid film. A linear stability analysis was adopted to predict ...On account of limited knowledge of the breakup of power law liquid film, the process of its disintegration and atomization was studied by using a planar liquid film. A linear stability analysis was adopted to predict the breakup characteristics of the power law film. The predicting formulas of stripping breakup length and diameter of ligament were put forward presently. Through high-speed photography and laser light sheet illumination,different breakup characteristics of flat power law film under different conditions were derived. The characteristic dimension of breakup regimes were defined and extracted. The effects of several parameters(injection pressure,ambient pressure, nozzle structure and fluid property) on the stripping breakup length and spray angle were investigated. The results revealed that increasing both the velocity of liquid film and the ambient pressure facilitated the breakup of film, reduced the stripping breakup length and enlarged the spray angle in different extents. The comparison between theoretical and experimental results was conducted to validate the feasibility of the linear stability theory.展开更多
Two varieties of fiddleneck (Phacelia tanacetifolia Benth.) plant were determined for visualizing somatic chromosomes. The 4-5 days old root tips were pre-treated in 6% a-monobromonaphtalane in +4 ℃ for 7.5 h, the...Two varieties of fiddleneck (Phacelia tanacetifolia Benth.) plant were determined for visualizing somatic chromosomes. The 4-5 days old root tips were pre-treated in 6% a-monobromonaphtalane in +4 ℃ for 7.5 h, then fixed in glacial acetic acid for 30 min and transferred to 70% ethanol for long storage. When the root tips were analyzed, they were hydrolyzed with 1 N HCI for 13 min at room temperature (25 ℃). After hydrolyzing, root tips were stained with 2% aceto orcein in darkness for 2.5 h. The squash method for preparation was used for chromosomal investigations. The chromosome length (C), relative length (RL), the long arm (L) and short arm (S) lengths, arm ratio (AR; L/S) and centromefic index (S/C) were calculated for caryologic parameters. The ideograms and detailed chromosome morphology measurements of the species were performed by the use of MicroMeasure 3.3. According to results, fiddleneck (Phacelia tanacetifolia Benth.) has 2n = 22 chromosomes and the karyotype formulas of two varieties of fiddleneck were 16 median and 6 submedian (16 m + 6 sm).展开更多
The scattering length formula was formulated and proved in special cases by Kac in 1974 and 1975.It was discussed by a series of authors,including Taylor 1976,Tamura 1992 and Takahashi 1990.The formula was proved by T...The scattering length formula was formulated and proved in special cases by Kac in 1974 and 1975.It was discussed by a series of authors,including Taylor 1976,Tamura 1992 and Takahashi 1990.The formula was proved by Takeda 2010 in symmetric case and by He 2011 assuming weak duality.In this article,we shall use the powerful tool of Kutznetsov measures to prove this formula in the general framework of right Markov processes without further assumptions.展开更多
This paper considers a discrete-time Geo/G/1 queue under the Min(N, D)-policy in which the idle server resumes its service if either N customers accumulate in the system or the total backlog of the service times of ...This paper considers a discrete-time Geo/G/1 queue under the Min(N, D)-policy in which the idle server resumes its service if either N customers accumulate in the system or the total backlog of the service times of the waiting customers exceeds D, whichever occurs first (Min(N, D)-policy). By using renewal process theory and total probability decomposition technique, the authors study the transient and equilibrium properties of the queue length from the beginning of the arbitrary initial state, and obtain both the recursive expression of the z-transformation of tile transient queue length distribution and the recursive formula for calculating the steady state queue length at arbitrary time epoch n+. Meanwhile, the authors obtain the explicit expressions of the additional queue length distribution, l^trthermore, the important relations between the steady state queue length distributions at different time epochs n , n and n+ are also reported. Finally, the authors give numerical examples to illustrate the effect of system parameters on the steady state queue length distribution, and also show from numerical results that the expressions of the steady state queue length distribution is important in the system capacity design.展开更多
基金Supported by the National Natural Science Foundation of China(11172205,11372219,51176137)
文摘On account of limited knowledge of the breakup of power law liquid film, the process of its disintegration and atomization was studied by using a planar liquid film. A linear stability analysis was adopted to predict the breakup characteristics of the power law film. The predicting formulas of stripping breakup length and diameter of ligament were put forward presently. Through high-speed photography and laser light sheet illumination,different breakup characteristics of flat power law film under different conditions were derived. The characteristic dimension of breakup regimes were defined and extracted. The effects of several parameters(injection pressure,ambient pressure, nozzle structure and fluid property) on the stripping breakup length and spray angle were investigated. The results revealed that increasing both the velocity of liquid film and the ambient pressure facilitated the breakup of film, reduced the stripping breakup length and enlarged the spray angle in different extents. The comparison between theoretical and experimental results was conducted to validate the feasibility of the linear stability theory.
文摘Two varieties of fiddleneck (Phacelia tanacetifolia Benth.) plant were determined for visualizing somatic chromosomes. The 4-5 days old root tips were pre-treated in 6% a-monobromonaphtalane in +4 ℃ for 7.5 h, then fixed in glacial acetic acid for 30 min and transferred to 70% ethanol for long storage. When the root tips were analyzed, they were hydrolyzed with 1 N HCI for 13 min at room temperature (25 ℃). After hydrolyzing, root tips were stained with 2% aceto orcein in darkness for 2.5 h. The squash method for preparation was used for chromosomal investigations. The chromosome length (C), relative length (RL), the long arm (L) and short arm (S) lengths, arm ratio (AR; L/S) and centromefic index (S/C) were calculated for caryologic parameters. The ideograms and detailed chromosome morphology measurements of the species were performed by the use of MicroMeasure 3.3. According to results, fiddleneck (Phacelia tanacetifolia Benth.) has 2n = 22 chromosomes and the karyotype formulas of two varieties of fiddleneck were 16 median and 6 submedian (16 m + 6 sm).
基金supported by National Natural Science Foundation of China(Grant Nos.11271240 and 11071044)
文摘The scattering length formula was formulated and proved in special cases by Kac in 1974 and 1975.It was discussed by a series of authors,including Taylor 1976,Tamura 1992 and Takahashi 1990.The formula was proved by Takeda 2010 in symmetric case and by He 2011 assuming weak duality.In this article,we shall use the powerful tool of Kutznetsov measures to prove this formula in the general framework of right Markov processes without further assumptions.
基金supported by the National Natural Science Foundation of China under Grant Nos.71171138,71301111,71571127the Scientific Research Innovation&Application Foundation of Headmaster of Hexi University under Grant Nos.XZ2013-06,XZ2013-09
文摘This paper considers a discrete-time Geo/G/1 queue under the Min(N, D)-policy in which the idle server resumes its service if either N customers accumulate in the system or the total backlog of the service times of the waiting customers exceeds D, whichever occurs first (Min(N, D)-policy). By using renewal process theory and total probability decomposition technique, the authors study the transient and equilibrium properties of the queue length from the beginning of the arbitrary initial state, and obtain both the recursive expression of the z-transformation of tile transient queue length distribution and the recursive formula for calculating the steady state queue length at arbitrary time epoch n+. Meanwhile, the authors obtain the explicit expressions of the additional queue length distribution, l^trthermore, the important relations between the steady state queue length distributions at different time epochs n , n and n+ are also reported. Finally, the authors give numerical examples to illustrate the effect of system parameters on the steady state queue length distribution, and also show from numerical results that the expressions of the steady state queue length distribution is important in the system capacity design.