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991.
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993.
V. Shanov C. Popov B. Ivanov A. Souleva G. Peev 《Journal of Materials Science: Materials in Electronics》1993,4(1):55-58
A new experimental approach for growth rate determination of microdimensional aluminium stripes written by laser-induced chemical vapour deposition (LCVD) was developed. The aluminium lines were obtained by pyrolysis of trimethylaluminium (TMA) on (100) silicon monocrystalline wafer using the focused beam of a copper bromide vapour laser. Quantitative determination of the deposit was performed by its chemical removal from the substrate into a solution and further analysis performed using inductively coupled plasma atomic emission spectroscopy. Using this analytical method, dependences of the aluminium quantity on the partial pressure of TMA and the laser power were obtained. The growth rate at direct writing with a pulsed visible laser was calculated on the basis of aluminium quantity determinations. It is demonstrated that the proposed experimental approach could be successfully used for kinetic studies of LCVD processes. 相似文献
994.
995.
996.
Translated from Izmeritel'naya Tekhnika, No. 7, pp. 43–44, July, 1989. 相似文献
997.
Translated from Steklo i Keramika, No. 1, pp. 8–10, January, 1992. 相似文献
998.
K.I. Popov N. Sultanova H. Rönkkömäki M. Hannu-Kuure J. Jalonen L.H.J. Lajunen I.F. Bugaenko V.I. Tuzhilkin 《Food chemistry》2006
The 13C NMR technique is used for the measurement of the first dissociation constant of sucrose (HL) in highly alkaline solutions. In 1.0 M NaCl/NaOH medium and for 25 °C, the concentration dissociation constant (pK1) was 13.1 ± 0.3; and, for 60 °C, pK1 = 12.30 ± 0.05. The β-d-fructofuranosyl ring was found to be responsible for dissociation. The NMR data reveal no clear evidence of the second dissociation step below pH 14, either at 25 °C or at 60 °C. In the solutions with 4–10 mol dm−3 NaOH content the 13C NMR technique indicated the chemical shift changes, treated as the second dissociation step of sucrose and a sodium complex formation. A very rough estimation, for variable ionic strength, gives the value: pK2 ∼ 15.8 ± 0.8. The anionic species L− and NaH−1L− have been registered by electrospray ionization time-of-flight mass spectrometry (ESI-ToF MS) for 0.01 M sucrose solutions with initial pH 13. 相似文献
999.
A. Yu. Popov 《Automation and Remote Control》2008,69(4):597-608
An oscillation process described by the system of linear differential equations with a constant matrix is considered. The matrix is supposed to have negative linearly independent, over the field of rational numbers, eigenvalues. For this system the explicit form of the minimum resource control is found. In the cases of the system dimension 1 and 2, the controls close to optimal are presented. 相似文献
1000.
Zhangwei Yu Anders Djupsjobacka Mikhail Popov Pierre-Yves Fonjallaz 《Photonics Technology Letters, IEEE》2007,19(4):233-235
Good performance of a direct optical microwave filter combined with direct detection consisting of a single superimposed grating used in reflection has been assessed through bit-error-rate (BER) measurement. In the passband with a 3-dB bandwidth of 2GHz, the BER is below 1.2times10-11, showing nearly on-off behavior of the filter 相似文献