Integration of the boltzmann equation in the relaxation time approximation

We integrate by very simple means the Boltzmann equation in the relaxation time approximation. Our result improves on the solution previously found by Chambers, which does not take into account initial conditions.     

Minimum permanents of doubly stochastic matrices with prescribed zero entries

A study of properties of matrices with minimum permanent in a face of the polyhedron of doubly stochastic n × n matrices. The minima are determined for certain faces.     

Local monotonicity structure of Calderón-Lozanovskiǐ spaces

We first prove that if x is an element on the unit sphere of arbitrary Köthe space E, x is strickly positive μ-a.e. and x is an LM-point, then x is an UM-point. Criteria for lower and upper monotone points in Calderón-Lozanovskiǐ spaces E_? are presented. Points of lower local uniform monotonicity and upper local uniform monotonicity in E_? are also considered. Some sufficient conditions and necessary conditions for these properties of a given point x in S(E_?⁺) are given.     

Resolution of multiexponential spectral relaxation of Yt-base by global analysis of collisionally quenched samples

We measured the wavelength-dependent intensity decays of 4,9-dihydro-4,6-dimethyl-9-oxo-1H-imidazo-1,2a-purine (Y_t-base) in propanol to determine the time-resolved emission spectra and rates of spectral relaxation. We found that resolution of the spectral relaxation times was dramatically improved by global analysis of the frequency-domain data with increasing amounts of the collisional quencher CCl₄. Collisional quenching preferentially decreases the longer-lived relaxed component of the emission, thereby increasing the fractional contribution of the incompletely relaxed portion of the emission. The data could not be explained by a single spectral relaxation time, and at least two relaxation times are needed to describe the time-dependent emission center of gravity of Y_t-base.Dedicated to Professor Stefan Paszyc on the occasion of his 70th birthday.     

Maluta's coefficient in Musielak-Orlicz sequence spaces equipped with the Orlicz norm

Maluta's coefficient of Musielak-Orlicz sequence spaces equipped with the Orlicz norm is calculated. A sufficient condition for the Schur property of these spaces is given.

     

Photochemical ring opening of barbital

Photolysis of barbital yields derivatives of urea and biuret. The mechanism of ring opening involves an isocyanate intermediate.     

On the nature of electron donor-acceptor interactions: 2. Mulliken's charge-transfer theory and the problem of the increase in intensity of the infrared band associated with iodine-base complexes

A relation between the enthalpy of formation and the rate of change with normal coordinate of the dipole moment contribution due to the charge-transfer phenomenon is derived for electron donor-acceptor complexes formed between halogen and organic molecules. The relation is found to hold for a number of iodine complexes.