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131.
The opto-mechanical characteristics, such as the specific mechanical recoil momentum, the specific impulse, and the energy efficiency, of the laser ablation of flat polymer targets ((C2F4) n , (CH2O) n ) have been determined experimentally for the first time for the case of excitation with femtosecond pulses (τ ∼ 45–70 fs) of UV-IR (λ ∼ 266, 400, 800 nm) laser radiation (I 0 up to 1015 W/cm2) under normal atmospheric and vacuum (p ∼ 10−4 mbar) conditions. The efficiency of mechanical recoil momentum generation is analyzed for various regimes of the laser irradiation.  相似文献   
132.
Let G be a group with identity e and let I \mathcal{I} be a left-invariant ideal in the Boolean algebra PG {\mathcal{P}_G} of all subsets of G. A subset A of G is called I \mathcal{I} -thin if gA ?A ? I gA \cap A \in \mathcal{I} for every gG\{e}. A subset A of G is called I \mathcal{I} -sparse if, for T every infinite subset S of G, there exists a finite subset F ⊂ S such that ?g ? F gA ? F \bigcap\nolimits_{g \in F} {gA \in \mathcal{F}} . An ideal I \mathcal{I} is said to be thin-complete (sparse-complete) if every I \mathcal{I} -thin (I \mathcal{I} -sparse) subset of G belongs to I \mathcal{I} . We define and describe the thin-completion and the sparse-completion of an ideal in PG {\mathcal{P}_G} .  相似文献   
133.
A method is developed for obtaining anisotropic composites based on the sulfonated cation-exchange MF-4SK and MK-40 membranes and the electroactive polymer polyaniline (PANI). The kinetics of aniline polymerization by successive diffusion in these membranes is investigated, and differences in the transport characteristics of the resulting MF-4SK/PANI and MK-40/PANI composites are identified. It is established from results of electroosmotic and diffusion experiments that the composite MF-4SK/PANI-1 membrane (after 1 h of aniline polymerization) suppresses electrolyte and water flow the most. Diffusion permeability drops by an order of magnitude, and water transport numbers are reduced by 50–70%. In the process of sodium chloride concentration by electrodialysis, the salt content of the concentrate increases by 50–70% with the composite MF-4SK/PANI-1 membrane compared to the base MF-4SK membrane and by 15–20% compared to the electrodialysis MK-40 membrane. Transport characteristics of the membrane pairs under investigation are calculated from the model of limiting concentration by electrodialysis: current efficiency, water transport numbers, osmotic and diffusion permeability. The dominant influence of the electroosmotic mechanism of water transport on the effect of salt solution concentration is established.  相似文献   
134.
135.
When selective laser melting technology is applied to fragile materials, a part can crack during the manufacturing stage. Stable SLM conditions are found for quartz glass, under which individual beads of remolten powder are manufactured. The beads are fused with a solid support of the same material. No cracking is observed in the beads or in the supports near the formers.  相似文献   
136.
Two non-discrete Hausdorff group topologies τ1, τ2 on a group G are called transversal if the least upper bound τ1τ2 of τ1 and τ2 is the discrete topology. We show that a countable group G admitting non-discrete Hausdorff group topologies admits c2 pairwise transversal complete group topologies on G (so c2 maximal group topologies). Moreover, every abelian group G admits 2|G|2 pairwise transversal complete group topologies.  相似文献   
137.
138.
Results of experimental studying hydrodynamic resistance and interplate entrainment of a plate deflector with a perforated plate are presented. The diapason of operational stability of the perforated plate with a plate deflector was determined. Analytical dependences for the calculation of the hydrodynamic resistance and the interplate entrainment were obtained.  相似文献   
139.
A new experimental technique for measuring magnetic characteristics of high-temperature superconducting (HTS) films is described. The measurement system includes a laser providing for local measurements. The measured magnetic characteristics of the HTS films are of scientific and practical interest.  相似文献   
140.
The antiproton-nucleus annihilation in two possible experimental situations (low energy in-flight annihilation and annihilation in a trap) is investigated taking into account the Coulomb interaction. For these two cases, the formulas giving the relation between the antiproton-nucleus scattering lengtha cs and observables (annihilation cross section and antiprotons time-of-life in a trap) are obtained. These relations are proposed to determinea cs.  相似文献   
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