New partitioning perturbation theory. I
Partitioning formalism for degenerate, almost degenerate and electron exchange perturbation problems
Certain, P. R.↗
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New partitioning perturbation theory. II
Coupled simple harmonic oscillators with almost degenerate energy levels, comparing partitioning perturbation techniques with Rayleigh- Schroedinger approach
Certain, P. R.↗
New partitioning perturbation theory. III
Partitioning perturbation theory for electron exchange problems, generalizing Hirschfelder- Silbey formalism
Certain, P. R.↗
Partition functions and equations of state in plasmas
Partition functions and equations of state of He, H, N, O, Ne, Ar, and solar plasmas - tables
Fischel, D.↗
On the rotational partition function for tetrahedral molecules
Tetrahedral molecules quantum mechanical rotational partition function, nuclear spin statistical weight factors and error bounds
Fox, K.↗
Partitioning of cations between coexisting single- and multi-site phases - A discussion
Cations partitioning between coexisting single and multisite phases in pyroxenes and olivines
Ghose, S.↗
Partition functions in ionizing plasmas
Ionizing plasmas partition functions, determining opacities and equations of state
Fischel, D.↗
Creep-fatigue analysis by strain-range partitioning
Creep-fatigue analysis by strain range partitioning, considering metals inelastic deformation at high temperature due to plastic flow
Halford, G. R.↗
Calculation of the partition function for super 14 N sub 2 super 16 O
Nitrous oxide internal and rotational partition functions for temperature range 200 to 350 K, using molecular constants tabulated by Pliva
Young, L. D. G.↗
Irradiation of linear polyethylene - Partitioning between sol and gel.
Molecular weight fractions of linear polyethylene were irradiated at 133 C, in the completely molten and highly crystalline states, for the purpose of assessing the importance of chain-scission processes and establishing the critical conditions for gelation. The partitioning between sol and gel in either state was found to adhere to the theory for the intermolecular cross-linking of monodisperse species for dosages just beyond the gel point. Deviations from theory occurred as the dosage was increased further. It was concluded that main-chain scission, at these temperatures, is not a significant process. High molecular weight samples in the completely molten state obeyed the Flory-Stockmayer condition for critical gelation.
Rijke, A. M.↗
Irradiation of linear polyethylene - Partitioning between sol and gel.
Investigation of the importance of chain-scission processes and of the applicability of the general theory of network formation to polyethylene with respect to critical conditions for gelation, using molecular weight fractions of linear polyethylene irradiated at 133 C. The partitioning between sol and gel was found to adhere to the theory just beyond the gel point. Deviations from theory occurred as the irradiation dosage was increased. It was concluded that main-chain scission at the temperatures concerned is not a significant process.
Rijke, A. M.↗
Creep-fatigue analysis by strain-range partitioning.
The framework of a new method is outlined for treating creep-fatigue behavior of metals. Inelastic strain-ranges are partitioned into the components of (1) completely reversed plasticity, (2) tensile plasticity reversed by compressive creep, or tensile creep reversed by compressive plasticity, and (3) completely reversed creep. Each of these components is shown to be related to cyclic life by a Manson-Coffin type power-law equation. A linear life fraction rule is used to combine the damaging effects of the individual components enabling the prediction of life. Test results are presented for a 2.25 Cr-1 Mo steel as well as limited information for a Type 316 stainless steel.
Manson, S. S.↗
Creep-fatigue analysis by Strainrange Partitioning
Strainrange Partitioning provides unifying framework for characterizing high-temperature, low-cycle, creep-fatigue properties of metals and alloys. Method offers distinct advantage to designers of immediately providing reliable upper and lower bounds on cyclic life for any type of inelastic strain cycle that may be encountered in service.
Manson, S. S.↗
The challenge to unify treatment of high-temperature fatigue - A partisan proposal based on strainrange partitioning
The strainrange partitioning concept divides the imposed strain into four basic ranges involving time-dependent and time-independent components. It is shown that some of the results presented at the symposium can be better correlated on the basis of this concept than by alternative methods. It is also suggested that methods of data generation and analysis can be helpfully guided by this approach. Potential applicability of the concept to the treatment of frequency and hold-time effects, environmental influence, crack initiation and growth, thermal fatigue, and code specifications are briefly considered. A required experimental program is outlined.
Manson, S. S.↗
Zr partitioning and kinetics and mechanism
The results of investigations concerning the cooling histories of lunar rocks are reported. Publications resulting from this research are listed. Studies discussed include the partitioning of Zr between FeTi03 and Fe2Ti04 in the presence of Fe + Zr02, and ulvospinel reduction.
Taylor, L. A.↗
The challenge to unify treatment of high-temperature fatigue - A partisan proposal based on strainrange partitioning.
The strainrange partitioning concept divides the imposed strain into four basic ranges involving time-dependent and time-independent components. It is shown that some of the results presented at the Symposium can be better correlated on the basis of this concept than by alternative methods. It is also suggested that methods of data generation and analysis can be helpfully guided by this approach. Potential applicability of the concept to the treatment of frequency and hold-time effects, environmental influence, crack initiation and growth, thermal fatigue, and code specifications are then briefly considered. A required experimental program is outlined.
Manson, S. S.↗
Partitioning of potassium between silicates and sulphide melts - Experiments relevant to the earth's core.
The partitioning of potassium between roedderite, K2Mg5Si12O30 and an Fe-FeS melt was investigated at temperatures about 40 C above the Fe-FeS eutectic. Roedderite was considered a prime candidate for one of the potassium-bearing phases in the primitive earth because roedderite and merrihueite are the only two silicates containing essential potassium which have been identified in stony meteorites. Application of the results to a primitive chondritic earth is discussed, and it is concluded that extraction of most of the earth's potassium into the Fe-FeS core would occur under the conditions in the early earth.-
Goettel, K. A.↗
Energy partitioning of gaseous ions in an electric field.
The partitioning of ion energy among thermal energy, drift energy, and random-field energy is studied by solution of the Boltzmann equation. An expansion in powers of the square of the electric field strength is obtained by Kihara's method. Numerical calculations for several ion-neutral force laws show that Wannier's constant mean-free-time model gives a reasonable first approximation. The formal extension to multicomponent mixtures is also given. The matrix elements obtained are tabulated, and can be used to study the field dependence of other moments of the ion-distribution function.
Hahn, H.-S.↗