Distribution of dipole and spin-dipole strength in nuclei

The schematic model of Goswami and Pal is applied to heavy nuclei and the dipole strength is shown to reside in just four non-degenerate levels. The collection of all the strength into a single level is discussed. The distribution of strength due to non-constancy of radial integrals and non-degeneracy of unperturbed particle-hole orbits is demonstrated in “realistic” calculations for ²⁰⁸Pb, ¹³²Sn, ⁹⁰Zr and ⁵⁶Ni. The collection of low energy dipole strength into “mini-resonances” is shown to be sensitive to the mean energy difference between neutron and proton particle-hole states.     

Interaction and rearrangement of trimethylsilyloxy functional groups. The structural significance of the m/e 147 ion in the mass spectra of trimethylsil steroidal ethers

Requirements for trimethylsilyloxy group interaction and rearrangement are discussed. It is evident that formation of the m/e 147 ion is a function of the stereochemistry, steric hindrance and separation of the trimethylsilyloxy groups and reflects the stereochemistry of the steroid itself. It is postulated that ring cleavage is not necessarily a prerequisite for the formation of this ion. The occurrence of the m/e 147 ion can be structurally informative in trimethylsilyl derivatives of steroidal alcohols.     

Mass relations and neutrino oscillations in an SO(10) model

We present in detail a grand unified model based on SO(10) which naturally reproduces known fermion mass relations and mixing angles. It predicts m_νe ? m_νμ, m_ντ, and predominant ν_μ-ν_τ oscillations. Several other features of the model are analyzed in detail: construction of the Higgs potential, predictions for τ_p and sin²θ_w in a temporarily free model and a relation between the mass of the t-quark and the lifetime of the B meson.     

The mass spectra of some corticosteroid boronates

The mass spectra of methyl, n-butyl, t-butyl, phenyl and cyclohexyl boronates of various classes of steroid are reported and discussed. Steroid types represented are 17α, 21-dihydroxy-20-ketones, 17α, 20, 21-triols, 17α, 20-diols, 20, 21-ketols. Each gives rise to characteristic fragmentation modes, although derivatives of the 20α- and 20β-hydroxy compounds have similar spectra.     

A branch and search algorithm for a class of nonlinear knapsack problems

This paper discusses a class of nonlinear knapsack problems where the objective function is quadratic. The method is a branch and search procedure which includes an efficient algorithm to find the continuous (relaxed) solution and a reduction rule which computes tight lower and upper bounds on the integer variables.     

Dynamics of heavy-ion transfer reactions

An exact calculation has been made of the kinematics for the transfer of one or more nucleons from projectile to target at bombarding energies above the Coulomb barrier. The calculation presumes that the transfer occurs in an overlapping region of the projectile and target. A comparison of calculated results with measurements of angular momentum transfer shows much better agreement than obtained from purely peripheral transfer calculations. The calculation also reproduces in detail the dependence of ejectile velocities on the ejectile mass and charge.