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1.
Russian Journal of General Chemistry - The review article traces the main trends of the synthetic approach to the solution of the problem of overcoming the resistance of pathogenic bacterial...  相似文献   
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The health monitoring has been studied to ensure integrity of design of engine structure by detection, quantification, and prediction of damages. Early detection of faults may allow the downtime of maintenance to be rescheduled, thus preventing sudden shutdown of machines. In cylinder pressure developed, vibrations and noise emissions data provide a rich source of information about condition of engines. Monitoring of vibrations and noise emissions are novel non-intrusive methodologies for which positioning of various transducers are important issue. The presented work shows applicability of these diagnosis methodologies adopted in case of diesel engines. The effects of changing various fuel injection parameters was analyzed. Scope of using non-intrusive technique has been analyzed by changing locations of microphone. Novelty of this worklies in exploring signal processing methods for various locations around the engine test set up. Various frequency ranges of contributing noise and vibration sources were identified. Time-Frequency analysis showed the onset of various cyclic. Based on the identification of various frequency bands, it is possible to device suitable filters in order to extract more information.  相似文献   
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The change in the free-electron density in ultrathin (5 nm) superconducting NbN films in the initial state and after irradiation by O+ ions to doses of (0.1–0.9) × 1017 cm–2 has been studied by electron energy-loss spectroscopy (EELS). The analysis has been performed on cross section samples prepared by the focused ion beam method, using plasmon oscillations with energies up to 50 eV. The radiation-induced replacement of nitrogen atoms with oxygen atoms in niobium nitride is found to change the electrical properties of the material, which leads to a decrease in the free-electron density with an increase in the irradiation dose.  相似文献   
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In the paper, the authors establish several integral representations for the generating functions of the large and little Schröder numbers and for the large and little Schröder numbers.  相似文献   
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We summarize the results of our recent work on Bäcklund transformations (BTs), particularly focusing on the relation between BTs and infinitesimal symmetries. We present a BT for an associated Degasperis–Procesi (aDP) equation and its superposition principle and investigate the solutions generated by applying this BT. Following our general methodology, we use the superposition principle of the BT to generate the infinitesimal symmetries of the aDP equation.  相似文献   
10.
Nanocomposites based on poly-N-vinylcaprolactam (PVC), characterized by different drying temperatures of aqueous PVC solution at 25°С (PVC25) and 40°С (PVC40), with titanium(IV) oxide nanoparticles (TONs) (η-phase (TP: TiO2 – x · mH2O) with a superstructure to the anatase structure and ordered solid solution with partial replacement of oxygen atoms in the η-phase with peroxo group O 2 2– (PP: TiO x (O2)2 – x · nH2O)) have been obtained for the first time and characterized by X-ray diffraction and IR spectroscopy. It is found that a common feature of TP/PVC and PP/PVC obtained by dry mixing and grinding is the decrease in the number of water molecules for TP and PP in the interlayer space of the structure and their attachment to the PVC amide groups; the differences are related to the specificity of PVC behavior in these systems: mechanodestruction of PVC in PP/PVC40 and different numbers of water molecules in PVC25 and PVC40.  相似文献   
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