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排序方式: 共有193条查询结果,搜索用时 15 毫秒
21.
Cecil J. Nesbitt 《Insurance: Mathematics and Economics》1982,1(4):255-260
A pension plan is said to be exactly vested if it provides in addition to the benefit available upon retirement, a benefit, upon termination for any cause prior to retirement, which is exactly equivalent to the actuarial accured liability for the terminating participant.The concept of exact vesting has simple application in defined contribution plans such as those of the Teachers Insurance and Annuity Association. It is also feasible to develop the exact vesting concept for a defined benefit plan which uses an individual type of actuarial cost method. An exactly vested plan would have more individual equity than is available under customary vesting and early retirement provisions of defined benefit plans.In this paper, theory is developed for an exactly vested model plan in parallel to the theory for a pure pension model plan discussed in previous papers on pension funding dynamics. 相似文献
22.
23.
The kinetics of the solvolysis of [Co(CN)5Cl]3? ions have been investigated in mixtures formed by the addition of ethane-1,2-diol or ethanonitrile to water where the physical properties indicate little enhancement of structure in water-rich conditions. The effect on the kinetics of this solvolysis of this lack of structural change in the solvent shows in the linearity of the variation of log (rate constant) with the reciprocal of the dielectric constant for the addition of ethane-1,2-diol to water and the absence of any prominent extrema in the enthalpy or entropy of activation using either co-solvent. However, the effect of changes in solvation on the solvolysis with these two co-solvents appears to operate in a similar manner to the effects found when the hydrophobic co-solvent propan-2-ol is added to water. The application of a free energy cycle to the process of the initial state going to the transition state for this dissociative process suggests that, with both co-solvents, [Co(CN)5]2? in the transition state is more stable than [Co(CN)5Cl]3? in the initial state. © John Wiley & Sons, Inc. 相似文献
24.
Cecil D. Bailey 《Foundations of Physics》1983,13(5):539-544
The law of varying action and Hamilton's principle of classical mechanics are discussed. It is now clear that the law of varying action, introduced by Hamilton in his papers of 1834 and 1935, was never recognized by either the mathematicians or other scientists who followed him. Why this occurred is discussed in this paper. 相似文献
25.
F.E. Cecil J.R. Shepard R.R. Sercely R.J. Peterson N.S.P. King 《Physics letters. [Part B]》1976,64(4):411-413
We have measured the differential cross sections for the reactions 12C(τ, τ′)12C(17.77 MeV 0+T=1) and 12C(τ, t)12N(2.43 MeV) at Eτ=44 MeV. The similar shapes of the angular distributions and the relative magnitudes of the cross sections suggest that the 12N 2.43 MeV level is the 0+T=1 analog to the q12C 17.77 MeV level. We have also studied the reaction 14N(p,t) 12N(2.43 MeV) at Ep=52 MeV. The strength with which this level is excited in this reaction is consistent with reasonable two-step calculations assuming the 2.43 MeV level to have Jπ=0+. 相似文献
26.
Precision densities and sound velocities for solutions of selected univalent electrolytes and nonelectrolytes in DMSO have been measured at 25°C, and apparent molar isentropic compressibilities and volumes evaluated. The data were extrapolated to infinite dilution to obtain standard state partial molar quantities, K
s,2
°
, and V
2
°
. Values of V
2
°
and K
s,2
°
for alkali metal halides in DMSO are very similar to those in water. The results confirm conclusions derived from data in water and other nonaqueous solvents that K
s,2
°
and V
2
°
for alkali metal halides are strongly dependent on solvent compressibility. K
s,2
°
becomes more negative and V
2
°
decreases as solvent compressibility increases. Attempts to determine ionic K
s,2
°
values suggest that a significant dissymmetry exists between 4P+ and 4B– in DMSO, whereas in water and MeOH, these large ions appear to behave similarly. Ionic V
2
°
values support this conclusion. Steric hindrance in the DMSO molecule is believed to be responsible for this dissymmetry. 相似文献
27.
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29.
Lyman R. Caswell Jo-Anne B. Campbell Rosemary Cecil 《Journal of heterocyclic chemistry》1979,16(2):225-230
The ultraviolet absorption, fluorescence, and infrared absorption spectra of fifteen 3-benz-amidophthalimides are described. In general, the nature or position of the substituents on the benzamide moiety has little effect on the ultraviolet absorption and fluorescence spectra of these, compounds. The absorption baud at 271 nm is more sensitive to substituent variations than the other two bands (at 227 nm and 341 nm), indicating this band is a composite of bands observed in the spectra of 3-aminophthalimide and the substituted benzamide. The fluorescence of 3-amino-phthalirnide and the 3-benzamidophthalimides is due to the same transitions. The infrared absorption wavenumbers for the amide and imide vibrations of the 3-benzamidophthalimides are characterized. 相似文献
30.
The spin-isospin flip (6Li, 6He) reaction has been studied. The experiment was performed with a 34 MeV 6Li beam incident upon 25, 26Mg and 27Al targets. Angular distributions associated with the lowest states were measured. Microscopic DWBA calculations were performed using Yukawa central and r2. Yukawa (r2 · Y) tensor (μ = 1.0 fm?1) potentials averaged over the 6Li(6He) cluster model wave functions. Knock-on (KO) exchange corrections corresponding to the central interaction are included using the local-energy approximation (LEA) method. The conclusion is that the quasi-elastic process is of major importance in the (6Li, 6He) transition studied in this work. 相似文献