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G. L. Sharipov R. Kh. Gainetdinov A. M. Abdrakhmanov 《Russian Chemical Bulletin》2008,57(9):1831-1836
The ultrasonic (20 kHz) multibubble sonoluminescence spectra of aqueous air- or argon-saturated solutions of CeCl3, TbCl3, and DyCl3 were obtained. Saturation with argon leads to the intensity redistribution in the spectrum of the continuum with an increase
in its short-wavelength part and increases the intensity of the characteristic emission of Ce3+ and Tb3+ due to the enhancement of the sonophotoluminescence intensity, i.e., the re-emission of the absorbed part of the continuum by these ions. The Ce3+, Tb3+, and Dy3+ ions quench the OH* emission at 310 nm with a qualitative correlation between the degree of quenching and the standard redox
potentials of the pairs LnIV/LnIII.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1797–1802, September, 2008. 相似文献
2.
G. L. Sharipov A. M. Abdrakhmanov R. Kh. Gainetdinov 《Russian Chemical Bulletin》2005,54(8):1793-1797
A comparative study of the sonoluminescence spectra of water and argon-saturated aqueous H2SO4 solutions was carried out. At an H2SO4 concentration of 18 mol L−1, the sulfuric acid sonoluminescence is fifty times more intense than water sonoluminescence. The sulfuric acid luminescence
spectrum differs from the water sonoluminescence spectrum caused by the emission of excited water molecules and OH radicals
from the gas phase of cavitation bubbles. The sulfuric acid sonoluminescence spectrum exhibits maxima at 330, 420, 500, and
630 nm. Emitters of sonoluminescence of sulfuric acid are the singlet (330–340 nm) and triplet (∼420 nm) excited SO2 molecules formed by sonolysis of H2SO4 molecules. Another product of sonolysis of H2SO4, atomic oxygen, is assumed to be responsible for the luminescence at λ = 630 nm.
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Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1742–1745, August, 2005. 相似文献
3.
Sharipov G. L. Abdrakhmanov A. M. Gainetdinov R. Kh. 《Russian Chemical Bulletin》2003,52(9):1966-1968
Sonoluminescence (SL) of aqueous solutions of sulfuric acid and sulfur dioxide enhances with an increase in their concentration and reaches a maximum at 16 and 0.05 mol L–1, respectively. The further increase in the concentration of these substances decreases the SL intensity. The SL spectra of the solutions have a broad maximum at 450 nm. Excited SO2 molecules formed in sulfuric acid due to sonolysis are luminescence emitters. The proposed mechanism of bright SL in these systems is based on the energy transfer from the electron-excited sonolysis products to the SO2 molecules in cavitation bubbles. 相似文献
4.
G. L. Sharipov R. Kh. Gainetdinov A. M. Abdrakhmanov 《Russian Chemical Bulletin》2005,54(6):1383-1386
A line of the GdIII ion was detected at 311 nm in the multibubble sonoluminescence spectrum of a concentrated (1 mol L−1) solution of gadolinium chloride. A comparison with the earlier studied sonoluminescence of the CeIII and TbIII ions shows that the GdIII ion is excited in the volume and/or on the surface of cavitation bubbles upon collisions with “hot” particles. The efficiency
of excitation of the lanthanide ions via this mechanism depends on the type of electron transition. For the same energy of the excited state, the efficiency of GdIII excitation (f-f transition) exceeds by at least 50 times that of CeIII excitation (f-d transition).
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1341–1344, June, 2005. 相似文献
5.
Sharipov G. L. Gainetdinov R. Kh. Abdrakhmanov A. M. 《Russian Chemical Bulletin》2003,52(9):1969-1973
The influence of salts (TbCl3, Tb(NO3)3, PrCl3, EuCl3, CeCl3, and DyCl3) on the spectrum and intensity of multi-bubble sonoluminescence (SL) of water was observed at a frequency of 20 kHz. Luminescence bands of the lanthanide ions were detected in the SL spectra of concentrated solutions of the CeIII, TbIII, and DyIII chlorides (0.1—1 mol L–1). No luminescence was observed for solutions of the other salts, and the shape of the spectra is due to the absorption of the water SL by the lanthanide ions. Possible mechanisms of the appearance of SL of lanthanides were considered. The first mechanism is the excitation of the lanthanide aqua ions in the solution bulk due to the absorption of the short-wave portion of glow of the excited water molecules and OH radicals emitted from the cavitation gas-vapor bubbles. The second mechanism involves the transfer of the lanthanide ions to the gas phase from the liquid layer adjacent to the cavitation bubble and their excitation in the bubble volume upon collisions with other hot or electron-excited particles. 相似文献
6.
R. G. Bulgakov D. I. Galimov Yu. G. Ponomareva E. Yu. Nevyadovskii R. Kh. Gainetdinov 《Russian Chemical Bulletin》2006,55(6):955-960
Quenching of electronically excited states of Ln3+* ions generated upon photoexcitation of toluene solutions of Ln(acac)3·H2O (Ln = Tb, Eu) complexes by C60 fullerene at 293 K was detected and investigated. The dependences of quenching efficiency on C60 concentration obtained from data on the decrease in the photoluminescence intensity and Ln3+* lifetimes obey the Stern-Volmer law. Quenching is due to inductive-resonant energy transfer from Ln3+* to C60 fullerene. The bimolecular rate constants for quenching, the overlap integrals of the Ln3+* photoluminescence spectra with the C60 absorption spectra, and the critical energy transfer distances were determined. No sensitized luminescence of C60 in the system studied was detected.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 921–925, June, 2006. 相似文献
7.
G. L. Sharipov R. Kh. Gainetdinov A. M. Abdrakhmanov 《Russian Chemical Bulletin》2008,57(9):1827-1830
A weak glow in the region of the Eu3+ photoluminescence spectrum was detected against the background of the continuum of the solvent emission during multibubble
sonolysis of air- or argon-saturated EuCl3 solutions (0.1 mol L−1) in heavy water. No characteristic sonoluminescence of the europium ion in aqueous solutions was observed earlier. Possible
reasons for the low yield of Eu3+ sonoluminescence compared with other lanthanide ions (Ln3+) are discussed and the influence of europium on the spectrum of the solvent continuum related, in particular, to quenching
of the electron-excited sonolysis products H2O* (D2O*) and Eu3+* in electron transfer reactions.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1793–1796, September, 2008. 相似文献
8.
G. L. Sharipov R. Kh. Gainetdinov A. M. Abdrakhmanov 《Russian Chemical Bulletin》2006,55(7):1114-1118
The effect of solvent deuteration on the multibubble sonoluminescence (SL) of an aqueous solution of terbium chloride was
studied. The dependence of the intensity of the characteristic SL of the TbIII ion on the composition of an H2O-D2O mixture is similar to an analogous dependence of its photoluminescence (PL) but with a much smaller isotope effect. In pure
D2O, the SL intensity increases by 4 times only compared to the SL in water, while the PL intensity increases by 10 times. The
mechanism of inner-bubble excitation of lanthanide ions is considered. According to this mechanism, an additional “heterogeneous”
channel of quenching of excited TbIII ions appears, which is absent for PL. The proposed model satisfactorily describes the experimental data on the effect of
solvent deuteration on the SL intensity.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1074–1078, July, 2006. 相似文献
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