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High-resolution measurements of the Kα 1,2 X-ray spectra were performed with a bent crystal diffraction spectrometer for zirconium, niobium, molybdenum and palladium targets bombarded by 280 and 360 MeV oxygen ions. The energy differences between the Kα 1,2 diagram and the K h α 1,2 hypersatellite transitions as well as the intensity ratios I ( K h α 1 )/ I ( K h α 2 ) were determined. The L-shell satellites of the diagram and of the hypersatellite lines were resolved. The data are interpreted in terms of the properties of He-like hole states in mid- Z atoms. The Breit interaction correction is determined. The corrections due to the unresolved M-shell satellites and to the QED are found to be much smaller than the Breit terms and comparable to the experimental accuracy.

High-resolution measurements of the K{beta}{sub 2} diagram line and its M{sup 1} satellite were performed for zirconium, molybdenum, palladium, and praseodymium. The x-ray spectra were induced by impact with 28-, 40-, 65-, and 100-MeV {alpha} particles and measured with a transmission-type bent crystal spectrometer in modified DuMond slit geometry. From the relative yields of the K{beta}{sub 2}M{sup 1} satellites the experimental average M-shell ionization probabilities for nearly central collisions were deduced. They are compared with theoretical predictions from the semiclassical independent particle approximation using either hydrogenlike wave functions (SCA-HWF) or Dirac-Hartree-Fock wave functions (SCA-DHF), pointing out the relevance of the use of DHF wave functions instead of hydrogenlike wave functions in the SCA model. Moreover, the experimental energy shifts of the satellite transitions with respect to the diagram lines are compared to results of extensive multiconfiguration Dirac-Fock calculations. {copyright} {ital 1998} {ital The American Physical Society}

$K{\ensuremath{\beta}}_{2}$ x-ray spectra of Zr, Mo, and Pd induced by photons and 16-, 25-, and 45-MeV protons were measured with a transmission bent crystal spectrometer. The average $M$-shell ionization probabilities were determined with the assumption that the yields in the $K{\ensuremath{\beta}}_{2}$ satellite region are due only to the $M$-shell ionization accompanying the removal of the $K$-shell electron. In the case of photoionization, these yields were found to exceed significantly those calculated with the sudden-approximation model for the shakeoff plus shakeup. Likewise, the corresponding yields for collisions with protons exceed those expected for the combined effect of the direct Coulomb ionization and the shake mechanism. The solid-state effects, as well as the direct knockout of the $M$-shell electron by the photoelectron (or the $\ensuremath{\delta}$ electron), are discussed in view of their possible effect on the line intensity in the satellite region. The direct Coulomb ionization probabilities in near central collisions with protons are determined from the difference of the relative yields of $\mathrm{K}{\ensuremath{\beta}}_{2}$ satellites in the proton-and photon-induced ionization. The underlying assumption is that the shake and solid-state effects are independent of the ionizing agent and that the secondary-electron ionization is similar in the two processes. The results are compared with the semiclassical approximation calculations exploiting relativistic hydrogenic and Dirac-Hartree-Fock wave functions.

The radiative decay of double K-shell vacancies in zirconium (Z=40), molybdenum (Z=42), and palladium (Z=46) was observed using a high-resolution transmission crystal spectrometer. The samples were ionized by the impact of 100-MeV $^{4}\mathrm{He}^{2+}$ ions. From the well resolved ${\mathit{K}}^{\mathrm{\ensuremath{-}}2}$\ensuremath{\rightarrow}${\mathit{K}}^{\mathrm{\ensuremath{-}}1}$${\mathit{L}}^{\mathrm{\ensuremath{-}}1}$ transitions, the energies, linewidths, intensity ratios, and double K-shell ionization cross sections were deduced. The experimental energies and linewidths of the hypersatellites are compared with results of Dirac-Hartree-Slater calculations and with multiconfiguration-Dirac-Fock calculations, both taking into account the Breit interaction. For the extracted double K-shell ionization cross sections a comparison is made with the semiclassical approximation predictions within the independent-particle model.

The Kα hypersatellite X-ray spectrum of 42Mo target bombarded with 17 MeV/u 16O ions was measured with a high-resolution transmission bent crystal spectrometer. Well resolved lines of L-satellites and K-hypersatellites of Kα1 and Kα2 transitions were observed. Such data give valuable and rich information for testing the approximation used for the description of the multielectron system. The Khα1 hypersatellite, treated as spin-flip 1S0→3P1 transition, is forbidden in pure L-S coupling. In that case the relative yields of the Kα hypersatellites reflect directly the degree of intermediate coupling in the atom. Moreover, energies of the Khα1.2L0,1 transitions and the I(Khα1L0,1)/I(Khα2L0,1) intensity ratios are much more influenced by the Breit interaction than the diagram lines. The discussion of these problems is illustrated with the measured Kα hypersatellite spectrum of 42Mo.

We tested how long unstained and unfixed films of blood and aspirated bone marrow could be kept before special cytochemical staining. To exclude influences other than time on the outcome of the reactions, all the material was taken from hematologically normal persons. A simple score was used to evaluate the results. These may be summarized as follows: in most cells Naphthol-AS-acetate-esterase first shows a progressive decline in reactivity after a delay of 6 weeks, the reaction becoming very weak after 10 +/- 1 weeks. This does not hold for monocytes, megakaryocytes and platelets, which maintain reactivity (and susceptibility to NaF) for more than three months. With PAS staining, a slight decrease in reactivity after 8 +/- 2 weeks could be observed, whereas all other stainings tested (POX, Sudan black B and Naphthol-AS-D-esterase) were unaffected even by a delay of up to 16 weeks.