ЗАВИСИМОСТЬ СИГНАЛА ГИГАНТСКОГО КОМБИНАЦИОННОГО РАССЕЯНИЯ СВЕТА ОТ ФОРМЫ СЕРЕБРЯНЫХ НАНОСТРУКТУР, ВЫРАЩЕННЫХ В ПОРАХ SiO2 /n-Si-ШАБЛОНА

Surface-enhanced Raman scattering is a powerful method used in chemoand biosensorics. The aim of this work was to determine the relationship between the signal of Surface-enhanced Raman scattering and the shape of silver nanostructures under the influence of laser radiation with different power.Plasmonic nanostructures were synthesized in silicon dioxide pores on monocrystalline silicon n-type substrate. The pores were formed using ion-track technology and selective chemical etching. Silver deposition was carried out by galvanic displacement method. Synthesis time was chosen as a parameter that allows controlling the shape of a silver deposit in the pores of silicon dioxide on the surface of single-crystal n-silicon during electrodeless deposition. Deposition time directly effects on the shape of metal nanostructures.Analysis of the dynamics of changing the morphology of the metal deposit showed that as the deposition time increases, the metal evolves from individual metallic crystallites within the pores at a short deposition time to dendritic-like nanostructures at a long time. The dependence of the intensity of Surface-enhanced Raman scattering spectra on the shape of the silver deposit is studied at the powers of a green laser (λ = 532 nm) from 2.5 μW to 150 μW on the model dye analyte Rodamin 6G. The optimum shape of the silver deposit and laser power is analyzed from this point of view design of active surfaces for Surface-enhanced Raman scattering with nondestructive control of small concentrations of substances.The silver nanostructures obtained in porous template SiO2 on n-type silicon substrate could be used as plasmon-active surfaces for nondestructive investigations of substances with low concentrations at low laser powers. Гигантское комбинационное рассеяние, усиленное поверхностью, является мощным методом, применяемым в хемо- и биосенсорике. Целью данной работы являлось определение взаимосвязи сигнала гигантского комбинационного рассеяния света с формой серебряных наноструктур при воздействии лазерного излучения с различной мощностью.Плазмонные наноструктуры синтезировались в порах диоксида кремния на подложке монокристаллического кремния n-типа, в котором поры формировались с использованием ионно-трековой технологии и селективного химического травления. Синтез серебра проводился методом безэлектродного осаждения. В качестве параметра, позволяющего управлять формой серебряного осадка в порах диоксида кремния на поверхности монокристаллического n-кремния при безэлектродном осаждении, выбрано время синтеза, которое непосредственно влияет на степень разрастания металлических наноструктур. Анализ динамики изменения морфологии металлического осадка показал, что при увеличении времени осаждения металл эволюционирует от отдельных металлических кристаллитов внутри пор при малых временах осаждения до дендритоподобных наноструктур при больших временах. Изучена зависимость интенсивности спектров гигантского комбинационного рассеяния света от формы серебряного осадка при мощностях зеленого лазера (λ = 532 нм) от 2,5 до 150 мкВт на модельном аналите Родамин 6Ж. Проведен анализ оптимальной формы серебряного осадка и мощности лазера с точки зрения последующего конструирования активных поверхностей для гигантского комбинационного рассеяния света при неразрушающем контроле малых концентраций веществ.Полученные серебряные наноструктуры в порах шаблона SiO2 на кремниевой подложке n-типа могут использоваться в качестве плазмонно-активных поверхностей при неразрушающем исследовании низких концентраций веществ на малых мощностях лазера.

INCREASING THE VILLAGE OF THE MOBILE CONTROL STATION COMMUNICATION SYSTEM IN EMERGENCIES

The article describes the topical problems of ensuring the viability of communication systems of mobile control center in extreme and crisis situation and gives recommendation on their main solutions

Platelet aggregation activity and beta-adrenoblocker therapy in patients with dilated cardiomyopathy

Aim. To investigate the specifics of ischemic and idiopathic dilated cardiomyopathy (DCMP), platelet aggregation activity, and the reaction of the latter to the beta-adrenoblocker (β-AB) therapy with atenolol or bisoprolol. Results. In DCMP patients, a significant increase in velocity and maximal amplitude of ADP-induced platelet aggregation, as well as a significant reduction in the time to the maximal aggregation amplitude, was observed. In both therapy groups, all parameters of platelet aggregation activity were significantly higher in ischemic vs. idiopathic DCMP patients. Long-term bisoprolol therapy provided a more manifested antiaggregant effect of the basis treatment, compared to atenolol therapy. Conclusion. DCMP patients, especially ones with ischemic DCMP, demonstrated an increase in platelet aggregation activity. Long-term bisoprolol therapy facilitated a more pronounced anti-aggregant effect of the basis treatment, compared to atenolol treatment

3D Silver Dendrites for Single-molecule Imaging by Surface-enhanced Raman Spectroscopy

Discovery of surface-enhanced Raman scattering (SERS) followed by evolution of optical systems and nanoengineering approaches has paved a path to detection of essential organic molecules on solid SERS-active substrates from solutions at concentrations attributed to single-molecule ones, i. e. below 10(-15) M. However, in practical terms confident SERS-imaging of single molecules is still quite a challenge. In present work, we fabricated and comprehensively characterized tightly-packed 3D silver dendrites with prevalent chevron morphology that demonstrated ultrahigh sensitivity as SERS-active substrates resulted in 10(-18) M detection limit. Using these substrates we achieved SERS-imaging of single 5-thio-2-nitrobenzoic acid (TNB) molecule released from the attomolar-concentrated solution of of 5,5 '-dithio-bis-[2-nitrobenzoic acid] (DTNB), which is vital compound for chemical and biomedical analysis. In contrast to generally accepted belief about adsorption of only uniform monomolecular TNB layer on surface of silver nanostructures, we showed formation of a coating constituted by TNB layer and DTNB nanoclusters on the dendrites' surface at 10(-6)-10(-12) M DTNB concentrations confirmed by presence/absence of disulfide bonds signature in the SERS-spectra and by scanning electron microscopy. DTNB concentrations below 10(-14) M resulted in adsorption of TNB molecules in separated spots on the surface of silver nanostructures

DEPENDENCE OF THE SURFACE-ENHANCED RAMAN SCATTERING SIGNAL ON THE SHAPE OF SILVER NANOSTRUCTURES GROWN IN THE SiO2 /n-Si POROUS TEMPLATE

Surface-enhanced Raman scattering is a powerful method used in chemoand biosensorics. The aim of this work was to determine the relationship between the signal of Surface-enhanced Raman scattering and the shape of silver nanostructures under the influence of laser radiation with different power.Plasmonic nanostructures were synthesized in silicon dioxide pores on monocrystalline silicon n-type substrate. The pores were formed using ion-track technology and selective chemical etching. Silver deposition was carried out by galvanic displacement method. Synthesis time was chosen as a parameter that allows controlling the shape of a silver deposit in the pores of silicon dioxide on the surface of single-crystal n-silicon during electrodeless deposition. Deposition time directly effects on the shape of metal nanostructures.Analysis of the dynamics of changing the morphology of the metal deposit showed that as the deposition time increases, the metal evolves from individual metallic crystallites within the pores at a short deposition time to dendritic-like nanostructures at a long time. The dependence of the intensity of Surface-enhanced Raman scattering spectra on the shape of the silver deposit is studied at the powers of a green laser (λ = 532 nm) from 2.5 μW to 150 μW on the model dye analyte Rodamin 6G. The optimum shape of the silver deposit and laser power is analyzed from this point of view design of active surfaces for Surface-enhanced Raman scattering with nondestructive control of small concentrations of substances.The silver nanostructures obtained in porous template SiO2 on n-type silicon substrate could be used as plasmon-active surfaces for nondestructive investigations of substances with low concentrations at low laser powers

3D silver dendrites for single-molecule imaging by surface-enhanced Raman spectroscopy

Discovery of surface‐enhanced Raman scattering (SERS) followed by evolution of optical systems and nanoengineering approaches has paved a path to detection of essential organic molecules on solid SERS‐active substrates from solutions at concentrations attributed to single‐molecule ones, i. e. below 10−15 M. However, in practical terms confident SERS‐imaging of single molecules is still quite a challenge. In present work, we fabricated and comprehensively characterized tightly‐packed 3D silver dendrites with prevalent chevron morphology that demonstrated ultrahigh sensitivity as SERS‐active substrates resulted in 10−18 M detection limit. Using these substrates we achieved SERS‐imaging of single 5‐thio‐2‐nitrobenzoic acid (TNB) molecule released from the attomolar‐concentrated solution of of 5,5′‐dithio‐bis‐[2‐nitrobenzoic acid] (DTNB), which is vital compound for chemical and biomedical analysis. In contrast to generally accepted belief about adsorption of only uniform monomolecular TNB layer on surface of silver nanostructures, we showed formation of a coating constituted by TNB layer and DTNB nanoclusters on the dendrites’ surface at 10−6–10−12 M DTNB concentrations confirmed by presence/absence of disulfide bonds signature in the SERS‐spectra and by scanning electron microscopy. DTNB concentrations below 10−14 M resulted in adsorption of TNB molecules in separated spots on the surface of silver nanostructures