The values of L, sub-shell fluorescence yields (a,) and Coster-Kronig transition probabilities (A,) were evaluated using radiative and non-radiative transition rates based on the relativistic Dirac-HartrMlater (RDHS) model for all the elements in the atomic number range 25 < 2 < 96. The values of the Coster-Kronig-corrected fluorescence (v3 and average L shell fluorescence (GL) yields were also evaluated and least-squares fitted to obtain the polynomials representing them as a function of atomic number.

The K, L, and higher atomic shell x-ray fluorescence yield measured data, covering the period 1978 to 1993, following the major previous compilations by Bambynek et al. (1972) and Krause (1979), are reviewed. An annotated bibliography of x-ray fluorescence yield measurements, analyses, fits and tables 1978–1993 is presented. Comparisons of the fluorescence yields ωk, ω̄L, and ω̄M, based on measurements, and on theoretical models, are presented. Values of ωK, ω̄L, and ω̄M, fitted to standard empirical parametric formulations, are presented. In addition, selected well-characterized measured ωK, ω̄L, and ω̄M results restricted to the period 1978–1993 are listed. These selected measured values are fitted by least squares to polynomials in Z of the form ∑nanZn and compared with theoretical and with earlier fitted values. A section on application of fluorescence yield data to computations of x-ray energy-absorption coefficients is included.

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8 2 for 2. 4 and 6, 8. The azimuthal angles are <1>1 + (i-I) (,r/2) and <1>2 + (i-5) ('11/2) for i=l-4 and 5-8 ligands.

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Next to xylanases, laccases from fungi and alkali-tolerant bacteria are the most important biocatalysts that can be employed for eco-friendly biobleaching of hard and soft wood pulps in the paper industry. Laccases offer a potential alternative to conventional, environmental-polluting chlorine and chlorine-based bleaching and has no reductive effect on the final yield of pulp as compared to hemicellulases (xylanases and mannanases). In the last decade, reports on biobleaching with laccases are based on laboratory observations only. There are several critical challenges before this enzyme can be implemented for pulp bleaching at the industrial scale. This review discusses significant factors like redox potential, laccase mediator system (LMS)-synthetic or natural, pH, temperature, stability of enzyme, unwanted grafting reactions of laccase, and cost-intensive production at large scale which constitute a great hitch for the successful implementation of laccases at industrial level.