DIFFERENT CHROMATOGRAPHIC BEHAVIOR OF A THYMINE-CONTAINING NEW ULTRAVIOLET PHOTOPRODUCT AND SPORE PHOTOPRODUCT

Abstract— One- and two-dimensional cochromatography in five different solvents of a near UV photo-product induced by 365 nm irradiation of DNA in aqueous solution and the 'spore photoproduct', 5-thyminyl-5,6-dihydrothymine, produced by 254 nm irradiation of dry DNA, indicate that the two photoproducts seem to have related structures but are different.     

Gluon effects and nonet mixing in the current quark picture

The effects on the meson mass spectrum of gluon interactions, and in particular of quark annihilation diagrams, are investigated in the current quark framework. The resulting mixing scheme leads to mixing angles θp ? ?13° and θ_V ? ? 52° for the pseudoscalar and vector nonets respectively, in moderate agreement with present data on radiative decays. For virtual electromagnetic processes additional gluon diagrams play a role. In η → 3π the net effect is to almost double the current algebra prediction, while in ω → 2π the ω → ?⁰ transition amplitude is correctly predicted in both sign and magnitude. The relation between the Hamiltonian approach and the U(1) problem, as formulated in terms of axial divergences, is briefly discussed.     

Elastic scattering and ω meson production near the threshold of π−p→ω+n

Measurements are reported of the differential cross section for the reaction π^?+p→ω+n from threshold to a final-state c.m. momentum $\text{P}{}^1\text{of}\text{200}\text{MeV}\text{/c}$. The previously reported fall in total cross section $\text{σ/P}{}^1$ below about 100 MeV/c is again seen. The differential cross section remains close to isotropic over the entire range. A paralle experiment on the variation in the elastic differential cross section across the threshold shows evidence of this threshold. The elastic data cover a range of incident moments from 1010 to 1180 MeV/c in steps of 5 MeV/c.     

Quantum vacuum cosmology

It is shown for the case of a conformally flat vacuum that the curvature of space-time may be viewed as the observable consequence of particle interactions involving a scalar field φ, rather than the independent agency of the gravitational field by itself. The quantum nature of gravity comes in as a consequence of the quantum properties of the φ-field (“vacuum fluctuation”), and a direct analogy is drawn between the renormalizations of charge and mass. Cosmological solutions are derived: These being just the conventional Friedmann solutions, or the de Sitter solution. It is pointed out that a totally empty universe must be Minkowskian.     

Diffusion of gallium into cadmium sulphide

Measurements of the Ga diffusion into CdS, in the presence of exces Ga metal, using optical and mixroprobe analyser techniques are reported. A reaction layer of CdGa₂S₄ forms on the CdS crystals below 1240±20 K. Above this temperature the reaction layer is liquid. The Ga diffusion is concentration dependent and also orientation dependent with the faster diffusion perpendicular to the hexagonal c-axis of CdS. The anisotropy of the activation energy was calculated to be 0.20±0.06 eV. In the temperature range 940–1240K the linearly concentration dependent diffusion yielded activation energy values for defect motion of 2.39±0.13 eV perpendicular to the c-direction and 2.21 ±0.13 eV parallel to the c-direction.     

Cyclopropane: Studies of some vibration-rotation Raman bands

An argon ion laser has been used to obtain vibration-rotation spectra of three perpendicular Raman bands of cyclopropane, ν₉(E′), ν₁₁(E′) and ν₁₂(E′), at a resolution of ca. 0.2 cm^?1. Analysis of their rotational structure has yielded several molecular constants, including Co = 0.4177 cm^?1.     

The 3B1-1A1 band system of sulfur dioxide: Rotational analysis of the (010), (100), and (110) bands

The (010)-(000) band of the ${}^3\text{B}{}_1\text{←}{}^1\text{A}{}_1$ system of sulfur dioxide has been rotationally analyzed and constants for the magnetic interactions in the (010) vibrational level determined. Partial rotational analyses are given for the rotationally perturbed (100)-(000) and (110)-(000) bands of the system. The extensive perturbations in this band system are provisionally attributed to: (i) vibronic interaction with a ³A₂ state, visible (a) as a large negative anharmonicity in higher bands of the ³B₁ system, and (b) as a ΔK = 0 resonance perturbation in low-lying vibrational levels of the ³B₁ state; and (ii) a K, K ± 1N-dependent perturbation possibly due to rotational-electronic coupling with a ³B₂ state, though evidence on this point is incomplete. Evidence bearing on these conclusions is discussed.     

Some properties of isospin waves in a neutron lattice

A dilute system of isospin waves in equilibrium with electrons in a neutron lattice should show Bose-Einstein condensation. The weak interaction of the condensate may cause damping of the free precession of neutron stars.     

Laser-microwave two-photon and double resonance spectroscopy of two linear molecules; HCCF and FCN

The technique of laser-microwave two-photon spectroscopy has been used to determine the frequencies of a number of transitions in fundamental and hot-bands of the two linear molecules HCCF and FCN. This method has previously only been applied in a systematic way to spectroscopy in NH₃ and it was the aim of this investigation to determine to what extent this method was applicable to more normal molecular species. The maximum effective tuning range produced with these molecules was ±3.7 GHz with a microwave power density of ?100 mW/cm² and a laser power density of ?40 W/cm². Transition frequencies were determined with accuracies up to ±3 MHz using a Lamb-dip technique. In the case of fluoroacetylene the observation of a number of double resonance signals involving direct l-type doubling transitions allowed determination of l-type doubling constants for the states (v₃ = 1, v₄ = 1) and (v₃ = 1, v₅ = 1). The P(12) C¹⁸O₂ laser line was shown to lie within the Doppler width of the upper l-type doublet R(25) transition of the (ν₃ + ν₄) ? ν₃ hot band. In this particular case velocity-tuned multiple photon dips were observed. The dispersive component of double resonance and two-photon Lamb-dip signals was observed to have opposite phase in two different vibrational states. The possible diagnostic value of this observation is discussed.