Moment singularities at angular corners in liquid crystals of nematic type

Summary A linear theory of axial plane reorientation in liquid crystals of nematic type is utilized to examine principal moment singularities which may occur at the vertex of corner boundaries. Reorientation free, moment free, and mixed boundary conditions are considered, and the order of the singularity as a function of the corner angle for these three cases is obtained.

---

Zusammenfassung Eine lineare Theorie der Achsenebenen-Neuorientierung an Flüssigkristallen vom nematischen Typ wird verwendet, um die Hauptmoment-Singularität zu untersuchen, die im Scheitel von Begrenzungen durch Ecken auftreten kann. Neuorientierungsfreie, momentenfreie, und gemischte Grenzbedingungen werden behandelt, und die Ordnung der Singularität als Funktion des Eckenwinkels wird für diese drei Fälle bestimmt.

---

---

This work was supported by the United States Energy Research and Development Administration.     

SU(3) breaking in the two-body decays of the Ψ(3100)

Motivated by the experimental fact that the ψ(3100) does not appear to behave like an SU(3) singlet when it decays into a vector pseudoscalar final state, we propose a model for SU(3) breaking in ψ decays. In the model we envision the ψ decay as a two-stage'process. In the first stage the quark-antiquark pair which comprises the ψ annihilate via a Zweig rule violating interaction to create a pair of “ordinary” quarks. We allow this interaction to violate SU(3) invariance so that all quarks may not be created equally. In stage two the quark pair turns itself into hadrons via a Zweig-allowed, SU(3)-invariant interaction. The data for the vector-pseudoscalar decays seem to indicate that the intermediate quark pair behaves like a heavy ω. We then use this “fact”. to make predictions for the baryon-antibaryon and the tensor-vector decays.     

Synthesis of single isomers (E or Z) of unsaturated alcohols by the horner-wittig reaction

Single isomers ($\text{E}$ or $\text{Z}$) of homoallylic and higher alcohols can be synthesised from ω-hydroxyalkyldiphenylphosphine oxides and aldehydes, or from alkyldiphenylphosphine oxides and lactones     

Orbital photography

A scheme is presented that enables photographic representation of the (two-dimensional) surfaces of (three-dimensional) molecular orbitals and electron density functions. The algorithm has been implemented by a program which is completely general and computationally efficient.     

Single-pion production in antiproton-proton interactions

Single-pion production in $\text{p}\text{p}$ interactions at 9.1 GeV/c is analysed and cross sections are given. The p_lab dependence of the isospin amplitudes is determined by a fit to the world data. The data are also compared with the predictions of a reggeized Deck model. The results and the $\text{N}\text{π}\text{N}$ amplitudes are compared with the results at other energies and with the corresponding NπN amplitudes.     

Inverse perturbation analysis: Improving the accuracy of potential energy curves

The equation for the first-order energy correction is used inversely to find the perturbation responsible for the energy correction. In the specific application to the calculation of a potential energy curve from the spectroscopic term values, the sought perturbation is a correction to an approximate potential curve. Consequently, an approximate potential curve (e.g. an RKR (Rydberg-Klein-Rees) curve) can be improved until the eigenvalues calculated for this curve agree with the spectroscopic term values within the experimental uncertainty. Results are given for the X²Σ⁺ state of HgH.     

Equilibrium charge-state fractions for 2.7–31 keV deuterium atoms and ions in strontium vapor

Equilibrium charge-state fractions of 2.7–31 keV deuterium in strontium vapor are reported. The energy dependence of the D^- equilibrium yield is discussed. The results are compared with the D^- yield in cesium and magnesium vapors.     

Inhibition of the kinetics of chelation of nickel (II) with malonate ion by β-cyclodextrin

Relaxation times, determined by the pressure-jump technique, for the kinetics of chelation of nickel (II) by malonate ion are significantly prolonged by the addition of β-cyclodextrin to aqueous solutions.The effect is due to inclusion of the malonate into the β-cyclodextrin cavity. In fact addition of glucose in a 7:1 ratio to malonate ion does not affect the kinetics of complexation with Ni²⁺. The effect is also specific to the size of the ring since α-cyclodextrin and γ-cyclodextrin do not show any effect on the above relaxation times.The kinetic data are interpreted to indicate a competitive inhibition process. β-cyclodextrin is bound to the anion and prevents its chelation reaction with Ni²⁺. The mechanism treats the data quantitatively with an inclusion formation constant between malonate and β-cyclodextrin of the order of 10²M^?1.