Phase Behavior of Melts of Diblock-Copolymers with One Charged Block

In this work we investigated the phase behavior of melts of block-copolymers with one charged block by means of dissipative particle dynamics with explicit electrostatic interactions. We assumed that all the Flory-Huggins \c{hi} parameters were equal to 0 and showed that the charge correlation attraction solely can cause microphase separation with long-range order; a phase diagram was constructed by varying the volume fraction of the uncharged block and the electrostatic interaction parameter {\lambda}. The obtained phase diagram was compared to the phase diagram of corresponding neutral diblock-copolymers. Surprisingly, the differences between these phase diagrams are rather subtle; the same phases are observed, and the positions of the ODT points are similar if the {\lambda}-parameter is considered as an "effective" \c{hi}-parameter. Next, we studied the position of the ODT for lamellar structure depending on the chain length N. It turned out that while for the uncharged diblock-copolymer the product \c{hi}crN was almost independent of N, for the diblock-copolymers with one charged block we observed a significant increase in {\lambda}crN upon increasing N. It can be attributed to the fact that the counterion entropy prevents the formation of ordered structures. This was supported by studying the ODT in diblock-copolymers with charged blocks and counterions cross-linked to the charged monomer units. The ODT for such systems was observed at significantly lower values of {\lambda} with the difference being more pronounced at longer chain lengths N. The diffusion of counterions in the obtained ordered structures was studied and compared to the case of a system with the same number of charged groups but homogeneous structure; the diffusion coefficient in a direction in the lamellar plane was found to be higher than in any direction in homogeneous structure

Bryophytes of Mordovia State Nature Reserve (European Russia)

The present study compiles the results of bryophyte species inventories made at the Mordovia State Nature Reserve from 2014 till 2016. The reserve is located near southern limit of deciduous-coniferous forest subzone. In total 96% of the reserve is covered by forests, where about half are pine forests. The annotated bryophyte checklist includes 142 moss species and 23 liverwort species. The data on collecting site characteristics, habitats, substrates, bryophyte species frequency, and sporophyte presence are provided. Presented treatment is a key contribution to the bryophyte flora of Mordovia and important for the knowledge on bryophyte distribution of this forested area within strongly anthropogenically disturbed European Russian landscape.

Raman Nonlinearity Contribution to Spatio-Temporal Pulse Dynamics Under Filamentation in Yag Crystal

We report on numerical study of the nonlinear pulse propagation under filamentation of femtosecond near-infrared radiation under normal dispersion regime in YAG crystal. Influence of the Raman and Kerr tandem action on a spatial and temporal dynamics of the laser pulse were discussed. We have shown that Raman nonlinearity provides an asymmetry of temporal pulse profile: the leading edge becomes more bright and propagates at larger distances in comparison with trailing edge. Keywords: filamentation, supercontinuum generation, Raman nonlinearity

Study of the structure of crater at the surface of 12Cr18Ni10Ti steel irradiated by high-power pulsed ion beam

The topography of surface layers of 12Cr18Ni10Ti (AISI 321) steel after pulsed high-power Cn+ ion beams irradiation was investigated by scanning electron microscopy. A thin foil was prepared from the cross section of a crater with the use of a focused ion beam in the column of a two-beam electron-ion microscope. The microstructure and chemical composition of the crater were studied by transmission electron microscop

Состояние глазной поверхности при псевдоэксфолиативном синдроме

In the article the ocular surface was assessed in groups of patients with and without pseudoexfoliative syndrome. Tear secretion (Schirmer test II) and break up time reduction and significant damage of conjunctiva surface (staining with fluorescein) weremarked in group of patients with pseudoexfoliative syndrome. According to questionnaire which reflects index of damage of ocular surface, clinical implications of ocular surface disease was higher in group of patients with pseudoexfoliative syndrome.Проведена оценка состояния глазной поверхности в группах обследованных с псевдоэксфолиативным синдромом и без него. В группе с псевдоэксфолиативным синдромом отмечается статистически значимое снижение слезопродукции (тест Ширмера II), времени разрыва слезной пленки и выраженное повреждение поверхности конъюнктивы (прокрашивание флюоресцеином). По данным опросника, отражающего индекс повреждения глазной поверхности, у пациентов с псевдоэксфолиативным синдромом более выражены клинические проявления синдрома сухого глаза

СОСТОЯНИЕ ТКАНЕЙ ГЛАЗНОЙ ПОВЕРХНОСТИ У ПАЦИЕНТОВ С ИНВОЛЮЦИОННЫМИ НАРУШЕНИЯМИ ПОЛОЖЕНИЯ НИЖНЕГО ВЕКА

The article presents the results of the evaluation of the state of the ocular surface in patients with involutional lower eyelid malpositions of atopic type. In the group with eyelid malposition was marked a statistically significant reduction in the time gap of the tear film and marked damage of the surface of the cornea and conjunctiva. According to the questionnaire, the index reflecting the damage to the ocular surface tissues in patients with malposition eyelids more pronounced clinical manifestations of dry eye syndrome. Therefore, involutional lower eyelid malpositions lead to the defeat of the ocular surface tissue, mainly due to the violation of the tear film stability and enhance its evaporation.Приведены результаты оценки состояния глазной поверхности у пациентов с нарушением положения нижнего века атонического характера. В группе с мальпозициями век отмечается статистически значимое снижение времени разрыва слезной пленки и выраженное повреждение поверхности конъюнктивы и роговицы. По данным опросника, отражающего индекс повреждения тканей глазной поверхности, у пациентов с мальпозициями век более выражены клинические проявления синдрома сухого глаза. Таким образом, инволюционные нарушения положения нижнего века приводят к поражению тканей глазной поверхности, преимущественно за счет нарушения стабильности слезной пленки и повышения ее испарения