Optical constatnts of yttrium-iron garnet single-crystal film strucrures

Light-attenuation spectra of yttrium–iron gar-net single-crystal film structures grown on a gallium–gadolinium garnet substrate by liquid-phase epitaxy from the undercooled solution in the melt have been studied and compared with those of bulk yttrium–iron garnet samples. The calculated optical constants are discussed tak-ing into account the influence of crystal field on the splitting of the energy states of iron ions in the film samples.

Metalloporphyrin - Organic Polymer Photosensitive Compositions: Experimental Studies and Computer Simulation of Photoprocesses

The dependence of porphyrin photobleaching vs. excitation power density has been found to be linear and points to a one-photon reaction type. The influence of pyridine and ethyl iodide additions and of molecular oxygen on the pigment decomposition rate has been investigated. Установлено, что зависимость фотообесцвечивания порфиринов от плотности мощности возбуждения имеет линейный характер и указывает на однофотонный тип реакции. Исследовано влияние добавок пиридина, йодистого этила и молекулярного кислорода на скорость разложения пигмента

ВЛИЯНИЕ КОМПОНЕНТНОГО СОСТАВА МИЦЕЛЛЯРНОГО РАСТВОРА НА СПЕКТРАЛЬНЫЕ СВОЙСТВА И СОЛЮБИЛИЗАЦИЮ ПЛЮРОНИКОМ ПРОИЗВОДНОГО БОРДИФТОРИД-ДИПИРРОЛИЛМЕТЕНА

It has been shown by a spectral method that the efficiency of solubilization of a borondifluoride dipyrromethene derivative by Pluronic F-127 inmixed systems depends on the proportions of mass concentrations of the dye and Pluronic in an initial liquid solution. It has been established that the values of the Pluronic F-127 concentration, at which the micelles solubilizing the dye are efficiently formed, exceed 10 % (mass). The analysis of spectral characteristics of the solution of the “dye – Pluronic” adducts has shown that the dye under study exists in the Pluronic micelles in the highest degree of disaggregation manifesting the spectral characteristics of monomeric form.Спектральным методом показано, что эффективность солюбилизации плюроником F-127 производного бордифторид-дипирролилметена зависит от соотношения в смешанных системах массовых концентраций красителя и плюроника в исходном жидком растворе. Установлено, что характерные значения концентраций плюроника в растворе, при которых образуются мицеллы, солюбилизирующие краситель, превышают 10 мас.%. Анализ спектральных характеристик рас- творов аддуктов «краситель–плюроник» показал, что исследуемый краситель в мицеллах плюроника находится в наибольшей степени дезагрегации, проявляя спектральные характеристики мономерной формы.

Unveiled optical properties of tetrapyrollic pigments in cryogenic environments

An unexpected phenomenon was revealed in the laser induced fluorescence spectra of free-base (H2Pc) and zinc (ZnPc) phthalocyanines trapped in rare gas and nitrogen matrices under a moderate increase in the laser intensity. In all matrices the intensity of an emission band near 755 nm increased drastically when pumping the S1 ← S0 transition. This observation was assigned to stimulated emission in a four-level scheme involving a vibronic transition from the lowest electronic state to a vibrational level of the ground state. In the present work, we expose new similar results obtained with porphyrin molecules, i.e. tetra-benzoporphin (TBP). With free-base H2TBP, stimulated emission was observed in Ar or N2 matrices, but not in Xe matrices. A possible reason could be a fast inter-system crossing rate due to the heavy atom effect induced by Xe. We also report the observation of persistent burnt spectral holes, although the low efficiency of this process is not competitive with stimulated emission and no decrease of the stimulated emission with time was observed. With ZnTBP, no stimulated emission could be recorded; however the appearance of rather strong phosphorescence was noticed. Similar studies focusing on the stimulated emission phenomenon is that they should allow new insights into site effects and site selectivity. PACS: 33.50.-j Fluorescence and phosphorescence; radiationless transitions, quenching (intersystem crossing, internal conversion); 33.80.-b Photon interactions with molecules; 78.47.-p Spectroscopy of solid state dynamics; 78.60.Lc Optically stimulated luminescence

Japanglish as a communication tool

Секция 3. Языковая парадигма в обучении иностранным языка

Japanglish as a communication tool

Секция 3. Языковая парадигма в обучении иностранным языка