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911.
钱会 《地球科学与环境学报》1987,(3)
本文在参阅Crerar D.A.等人的资料的基础上,比较系统地论述了水溶液中各种化学组分可能存在形式分配及Eh值的计算方法。文章从对施实计算所需的原始数据的说明开始,主要从以下几个方面说明了计算方法:1.热力学问题的数学描述;2.问题的数值解;3.活度系数的校正;4.迭代步骤;5.Eh值的计算。文中以华清池温泉水化学分析资料为例,分别给出了此资料在12℃和42℃时的计算结果。由于分析技术和计算方法的误差,Eh值的计算结果存在一定的偏离,这也可能是由于给定温度下水中某些组分间存在着非平衡而引起的。 相似文献
912.
lareODUcrIONThetotalcarbondi0xideisandriportantparametrforestirnatingthespatiotem0ralinorganiccarbontransport,andanthropogeniccarb0ndi0xideincreasesintheoonn.Ap~coulomericednique(MethodG0fASTMD5l3-82)formeasuringDICinanwaterdevelopedbyJohnsonetal.(l985)istheshipkoardmehodchosenfortheglobeocanicinofganiccarb0nsurveyt0bemadeinconjunCtionwiththeW0riddrinCirmlationExperirnentWorklHydrographicProgram(WOCEWHP)andtheJointGobal~nFluxStudy(JGOFS)program(Catherine,G.etal.,l993).Thecruxof… 相似文献
913.
This paper presents the procedure of a computational scheme leading to approximate general solution of the axi-symmetric,2-degrees
of freedom dynamical systems. Also the results of application of this scheme in two such systems of the non-linear double
oscillator with third and fifth order potentials in position variables. Their approximate general solution is constructed
by computing a dense set of families of periodic solutions and their presentation is made through plots of initial conditions.
The accuracy of the approximate general solution is defined by two error parameters, one giving a measure of the accuracy
of the integration and calculation of periodic solutions procedure, and the second the density in the initial conditions space
of the periodic solutions calculated. Due to the need to compute families of periodic solutions of large periods the numerical
integrations were carried out using the eighth order, variable step, R-K algorithm, which secured for almost all results presented
here conservation of the energy constant between 10-9 and 10-12 for single runs of any and all solutions. The accuracy of the approximate general solution is controlled by increasing the
number of family curves and also by `zooming' into parts of the space of initial conditions. All families of periodic solutions
were checked for their stability. The computation of such families within areas of `deterministic chaos' did not encounter
any difficulty other than poorer precision. Furthermore, on the basis of the stability study of the computed families, the
boundaries of areas of `order' and `chaos' were approximately defined. On the basis of these results it is concluded that
investigations in thePoincaré sections have to disclose 3 distinct types of areas of `order' and 2 distinct types of areas
of `chaos'. Verification of the `order'/`chaos' boundary calculation was made by working out several Poincaré surfaces of
sections.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
914.
915.
We present a symplectic mapping model to study the evolution of a small body at the 3/4 exterior resonance with Neptune, for planar and for three dimensional motion. The mapping is based on the averaged Hamiltonian close to this resonance and is constructed in such a way that the topology of its phase space is similar to that of the Poincaré map of the elliptic restricted three-body problem. Using this model we study the evolution of a small object near the 3/4 resonance. Both chaotic and regular motions are found, and it is shown that the initial phase of the object plays an important role on the appearance of chaos. In the planar case, objects that are phase-protected from close encounters with Neptune have regular orbits even at eccentricities up to 0.44. On the other hand objects that are not phase protected show chaotic behaviour even at low eccentricities. The introduction of the inclination to our model affects the stable areas around the 3/4 mean motion resonance, which now become thinner and thinner and finally at is=10° the whole resonant region becomes chaotic. This may justify the absence of a large population of objects at this resonance. 相似文献
916.
A simplified method of numerical analysis based on elasticity theory has been developed for the analysis of axially and laterally loaded piled raft foundations embedded in non‐homogeneous soils and incorporated into a computer program “PRAB”. In this method, a hybrid model is employed in which the flexible raft is modelled as thin plates and the piles as elastic beams and the soil is treated as springs. The interactions between structural members, pile–soil–pile, pile–soil–raft and raft–soil–raft interactions, are approximated based on Mindlin's solutions for both vertical and lateral forces with consideration of non‐homogeneous soils. The validity of the proposed method is verified through comparisons with some published solutions for single piles, pile groups and capped pile groups in non‐homogeneous soils. Thereafter, the solutions from this approach for the analysis of axially and laterally loaded 4‐pile pile groups and 4‐pile piled rafts embedded in finite homogeneous and non‐homogeneous soil layers are compared with those from three‐dimensional finite element analysis. Good agreement between the present approach and the more rigorous finite element approach is demonstrated. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
917.
在简单的假定下。建立了一类非线性二阶奇异初值问题C^1[0,1]正解存在的充分必要条件,我们的奇异问题在有奇性。 相似文献
918.
E.A. Perdios 《Astrophysics and Space Science》2003,286(3-4):501-513
In this paper, we determine series of horizontally critical symmetric periodic orbits of the six basic families, f,g,h,i,l,m, of the photogravitational restricted three-body problem, and computetheir vertical stability. We restrict our study in the
case where only the first primary is radiating, namely q
1≠1 andq
2=1. We also compare our results with those of Hénon and Guyot (1970) so as to study the effect of radiation to this kind of
orbits.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
919.
Periodic Orbits of a Collinear Restricted Three-Body Problem 总被引:6,自引:0,他引:6
In this paper we study symmetric periodic orbits of a collinear restricted three-body problem, when the middle mass is the largest one. These symmetric periodic orbits are obtained from analytic continuation of symmetric periodic orbits of two collinear two-body problems. 相似文献
920.