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1.
The angular variations of the five-fold differential cross section obtained by using different wave functions of helium are compared with experimental data. It is found that in the coplanar geometry two kinematical arrangements, (i) equal energy sharing between the two ejected electrons with one of them ejected along the momentum transfer direction and the other along varying direction and (ii) the Bethe ridge condition with fixed sum of ejected electron energies and varying angle between them, are very sensitive to e-e correlations contained in the target wave function. This comparison has been used to show that open-shell class of wave functions better incorporate e-e correlations than the closed-shell class.  相似文献   
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New experimental data on the cross sections for the yield of excited 6Li* and 7Li* nuclei and on their contributions to the production of 4He + 2H and 4He+3H light dinuclear systems in 16O p collisions at a momentumof 3.25 A GeV/c per nucleon are presented.  相似文献   
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The next generation of linear colliders is very demanding concerning the alignment tolerances of their components. For the CLIC project, the reference axis of the components will have to be pre-aligned within 10 μm at 1 sigma with respect to a straight line in a sliding window of 200 m. A solution based on stretched wires with wire positioning sensors has been proposed in order to fulfill the alignment requirements in the Conceptual Design Report of the project. This solution has some drawbacks and laser based alternative solutions are under study in order to validate the wire solution and possibly replace it. A new proposal is introduced in this paper, using a laser beam over 150 m as a straight alignment reference, with the objective of having an uncertainty in the determination of its straightness within 10 μm. Sensors coupled to the components to be aligned, would provide after calibration the horizontal and vertical offsets with respect to the laser beam, within a few micrometers, in their coordinate system. The method is based on the laser beam space stabilization effect when a beam propagates in atmospheric air inside a pipe with standing acoustic wave. The principal schemes of corresponding optoelectronics devices and temperature stabilization solutions are also proposed, making probable the extension of the laser fiducial line up to a 500 m length.  相似文献   
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Recently, photodynamic therapy (PDT) has been used for the treatment of festering wounds and trophic ulcers. An important advantage of PDT is its ability to affect bacterial cultures that are resistant to antibiotics. However the use of PDT alone does not usually guarantee a stable antiseptic effect and cannot prevent an external infection of wounds and burns. In this work attention is focused on the healing of the extensive soft tissues wounds with combined laser therapy (LT) and PDT treatment. At the first stage of this process festering tissues (for example spacious purulent wounds with area more than 100 cm2) were illuminated with high-energy laser beam (with power 20 W) in continues routine. The second stage involves “softer” PDT affect, which along with the completion stages of destruction pathological cells, stimulating the process of wound granulation and epithelization. Also, according to our previous results, photosensitizer (photoditazin) is introduced inside the wound with different amphiphilic polymers for increasing the PDT efficacy.  相似文献   
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Experimental data on inclusive deuteron production in 16Op collisions at high energies were obtained for the first time under conditions of 4π geometry. An irregularity in the momentum spectrum of deuterons in the rest frame of oxygen nuclei is found in the range 0.40 ≤ p ≤ 0.55 GeV/c, and the reasons for its appearance are discussed. The mean multiplicities of secondary fragments are correlated with the presence of deuterons in an event, these correlations being positive for fragments of charge in the range z f ≤ 4 and negative for fragments of charge in the range 5 ≤ z f ≤ 7. This is likely to be due to baryon-charge conservation.  相似文献   
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This work is to show that activity of porphyrins in singlet oxygen generation (SOG) is determined not only by their molecular structure but also by supramolecular structure of porphyrin containing systems. This is demonstrated by results of studies of SOG in the gas phase by vacuum deposited tetraphenylporphyrin (TPP) layers under photoexcitation conditions. The structure of the layers was studied by atomic force microscopy (AFM), TEM in diffraction regime (TED) and by the flicker-noise spectroscopy (FNS) method. It was shown that substrates affect the deposited layers structure only at earlier stages of the layer formation. AFM and TED data, together with FNS quantitative parameters of TPP layers, show directly that the chemical activity of solid-phase systems can be determined not only by their chemical nature but also by their supramolecular structure.  相似文献   
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