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A l’occasion de bilans fonctionnels respiratoires, l’étude de l’épuration du poumon profond a été effectuée sur deux groupes de sujets, composés, l’un, de 20 sujets normaux, l’autre, de 18 sujets atteints pour la plupart d’affections diverses : sarcoïdose, tuberculose, bronchite chronique, et pneumoconiose. Chaque groupe comprend des sujets fumeurs et non fumeurs. Le produit administré sous forme d’aérosol est pour le premier de l’or 198, pour le deuxième des billes de polystyrène marquées au chrome 51. Les mesures effectuées à l’aide d’une installation de spectrométrie gamma pour l’ensemble du corps, à bas niveau d’activité, ont été conduites pendant plusieurs semaines ou plusieurs mois. Les courbes de rétention sont d’allure exponentielle, et les périodes calculées sont comparées à diverses données : âge, sexe, profession, consommation de tabac, épreuves spirométriques, étiologie dans le cas des malades. La période biologique normale est voisine de 68 jours : elle est augmentée de façon significative par la consommation de tabac : elle est allongée également dans les états pathologiques considérés, excepté dans la sarcoïdose

A covalent model is presented for the contribution of the orbital part in μBL · H of the Zeeman Hamiltonian to the anisotropy of the magnetic field effect on the 4E(G) level at lower energy of Mn2+ in ZnS. First, the coefficients dgA1 and dgE which describe the influence of μBL · H are given in terms of the matrix elements of a second-order perturbation scheme involving the spin–orbit (SO) interaction and the orbital operator in L · H. Second, a molecular model involving the molecular SO interaction is elaborated. It is shown that the theoretical values dgA1 th = 0.025 cm—1 and dgE th = 0.040 cm—1 as given by the covalent model are in good agreement with the experimental values dgA1 exp = 0.02 cm—1 and dgE exp = 0.04 cm—1. Third, the theoretical values given by the covalent model are compared to the values given by the crystal field (CF) model. Finally, the influence of the Jahn-Teller effect on dgE is briefly analyzed.

It is shown that the magnetic field effect permits to unambiguously determine the nature of the fine structure lines of the fluorescent level 4T1 of a d5 ion coupled to ɛ-vibrational modes. Polarized excitation spectra of the fluorescent 4T1 level of Mn2+ in pure cubic ZnS have been obtained up to 5 T by using polarization modulated laser spectroscopy performed at 1.9 and 4.2 K for B ∥[001]∥ k and B ∥[111]∥ k. The energies and relative dipole strengths (RDS) of the Zeeman transitions between the fundamental and the excited states, are correctly described by Ham's phenomenological model for orbital triplet states and the Zeeman Hamiltonian μBgeS · H.

We show that for d5ions in Tdsymmetry, Jahn-Teller interactions or anomalous dipole strengths (DS) complicate strongly the analysis of the structure of zero-phonon lines (ZPL) of triplet levels. We also show that a careful study of uniaxial stress effects, such as shifts, splittings, and polarization of the ZPL's gives detailed information not only on Jahn-Teller interactions but also on the mechanisms involved in the dipole strength calculations.

A high resolution study of the magnetic field effect on the fundamental vibronic lines (FVL) of the 4T2 level at lower energy of Mn2+ in pure cubic ZnS has been made in order to analyze the vibronic structure of this level. First, very detailed excitation spectra σ+ and σ— of the two observed FVLs corresponding to transitions 6A1 → 4T2 have been obtained by using polarization-modulated laser spectroscopy performed at 1.9 K, for B ∥ [001] and B → [111]. Second, the theoretical energies and relative dipole strengths (RDS) of the transitions between the Zeeman levels 6A1 (MS = —5/2 to MiiS = +5/2) of the fundamental level and the Zeeman levels of the Kramers doublets Γ6(4T2), Γ7(4T2), and spin quartets Γ'8(3/2) (4{T2), Γ'8(5/2) (4{T2), have been analyzed in terms of the Zeeman Hamiltonian μBgeS · H and in terms of three coefficients which account for the splitting and RDS of the fundamental vibronic lines in zero magnetic field. Finally, by comparing the theoretical and experimental spectra, it is shown that the model of a strong coupling to ɛ-vibrational modes must be rejected and that, for the proposed model, the two observed lines are associated to transitions |6A1〉 → |Γ'8(5/2) (4T2)〉 and |6A1〉 → |Γ6(4T2)〉, the transition |6A1〉 → |Γ'8(3/2) (4T2)〉 being strongly attenuated by selective intensity transfer due to a medium coupling to ɛ-vibrational modes, and the transition |6A1〉 → |Γ7(4T2)〉 being forbidden by symmetry.

A very precise determination has been made of the contribution of the terms μBgeH · S and μBL · H of the Zeeman Hamiltonian to the anisotropy of the magnetic field effect on the 4E(G)-level of Mn2+ in ZnS. First, detailed excitation spectra from Kramers doublets |(4E) Γ6〉, |(4E) Γ7〉, and spin quartet |(4E) Γ8〉 to fundamental Zeeman states |(6A1) SMS〉, have been analyzed up to 5 T for B ∥ [001] and B ∥ [111]. Second, for B = 5 T, T = 2 K, angular variations of transitions |(4E) Γ6〉, |(4E) Γ7〉 and |(4E) Γ8〉 → (6A1)SMS = —5/2〉 have been studied for B rotating around the axis [1-10]. For all orientations of the magnetic field, the experimental and theoretical energy levels as given by the Hamiltonian μBgeH · S, differ by at most 0.2 cm—1. Finally, the very small contribution of the term in μBH · L has been studied by using an equivalent operator mimicking the second-order perturbation schemes involving the spin–orbit interaction and the operator L · H.

The first-order spin–orbit (SO) interaction for the fluorescent ⁴T1-levels of Mn2+ in the common cation series ZnX (X: S, Se, Te) has been calculated by using the molecular SO interaction HSO mol and a very elaborated ligand-field (LF) model. With respect to the splittings predicted by the crystal-field (CF) model, the first-order SO splittings are very strongly reduced for Mn in ZnS, while for Mn in ZnSe and ZnTe, the splittings are inversed and strongly enhanced. A theoretical check of the validity of the LF model is performed by relating the matrix elements of the total angular momentum for the monoelectronic wave functions 2e and 2t2 which intervene in the calculation of the matrix elements of the first-order SO interaction to those which intervene in the calculation of the spin–lattice coupling coefficients (SLCC). Another check of the validity of the LF model from a previous analysis of the four vibronic lines of the fluorescent level of Mn²⁺ in ZnS is briefly recalled.

Thirty-nine patients with squamous cell carcinoma of the bronchus were randomized into two groups after radical surgery. The first group of 18 patients received 75 mg of living BCG on a scratched area once a week; the second group of 21 patients received no further treatment. After 2 years 3 patients of the group treated with BCG are dead and 1 is in relapse; 8 patients of the control group are dead and 2 are in relapse.