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901.
The parameters of fuel oil pyrolysis initiated by propane-butane-oxygen flame were studied as influenced by the temperature in the pyrolysis zone, time of the fuel oil contact with the initiating flame, and fuel oil feed rate. The experimental data on thermal and flame-initiated fuel oil pyrolysis were compared.  相似文献   
902.
Translated from algebra i Logika, Vol. 30, No. 6, pp. 693–704, November–December, 1991.  相似文献   
903.
904.
905.
Emission spectra and decay kinetics of pulsed cathodoluminescence of a natural IIa-type diamond sample are investigated in the spectral range 340–680 nm. The luminescence of the vibronic N3-system and band A are observed. The N3-system is dominant on a nanosecond scale and has a 415.2-nm zero-phonon line with phonon replicas in the range 430–460 nm. The decay time for the N3 system is found to be 30–50 ns. Structureless band A is observed on a millisecond scale; it has a maximum at 460 nm and a decay time of 8.5–8.8 ms. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 53–57, January, 2007.  相似文献   
906.
The structure of a spin spiral arising in the vicinity of the interface between a ferromagnet and a compensated antiferromagnet is studied in the case where the anisotropy axes of the layers are parallel to each other, and the evolution of this spiral in an external magnetic field is investigated.  相似文献   
907.
Potentialities of observing spatially localized inhomogeneities by the low-frequency low-mode pulsed diffraction tomography in a shallow sea are analyzed. A numerically simulated model is used to study the procedure of reconstructing the parameters of inhomogeneities by coprocessing the signals of the tomographic projections formed at the multistatic excitation and reception of low-frequency low-mode acoustic pulses.  相似文献   
908.
The use of compressive crushing equipment such as gyratory crushers within minerals processing plants can potentially generate large quantities of dust. Remedies to this problem include the retrofitting of shrouds, enclosures, local exhaust ventilation (LEV) systems and water suppression systems. The single or combined application of these systems must be optimised to ensure they operate efficiently. It is desirable that the future design planning of such facilities include integrated dust suppression and/or removal systems to ensure material delivery rates are maintained and the welfare of the workforce is protected.  相似文献   
909.
Experimental results from HERA on diffractive vector meson production and their theoretical interpretation within microscopic QCD are reviewed with an emphasis on the BFKL color dipole and k T -factorization approaches. The text was submitted by the authors in English.  相似文献   
910.
The evolution of the structure organization of MOCVD-grown AlGaN/GaN superlattices subjected to erbium ion implantation with an energy of 1 MeV and dose of 3 × 1015 cm?2 and subsequent annealing is correlated with their photoluminescent properties. The structure organization is quantitatively estimated using parameter Δ (degree of violation of local symmetry), which is found via multifractal analysis of surface morphology patterns obtained with atomic force microscopy. It is shown that the implantation not only causes Ga segregation on the surface, but also changes the structure organization, which shows up in the finer grain structure compared with the starting one and disordering, as well as in an increase in Δ. As the annealing temperature rises from 700 to 800°C, Δ declines, indicating that the structure organization is improved, and the intensity of the dominating photoluminescence peak due to Er3+ ions (1.542 μm) grows. With a further increase in the annealing temperature to 1050°C, the structure organization degrades, domains get larger, voids 100–200 nm deep form, and the photoluminescence intensity drops. The formation of voids during high-temperature annealing is also substantiated by data for 230-keV proton scattering. It is thus established that the improvement of the superlattice structure organization activates erbium and causes the erbium-ion-related luminescence intensity to grow.  相似文献   
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