Thermally active interphase inclusion in a smooth contact conditions with transversely isotropic half-spaces

An exact solution of the stationary thermoelasticity problem about interfacial circular absolutely rigid inclusion, which is in the smooth contact conditions in a piecewise homogeneous transversely homogeneous space, is constructed. The task with the help of the constructed discontinuous solution, by the method of singular integral relations, is reduced to a system of singular integral equations (SIE). An exact solution has been built for the specified SIE, as a result, dependences of translational displacement of the inclusion on temperature, the resultant load, main moment and thermomechanical characteristics of transversely isotropic materials have been obtained

Fatty acid acylated Fab-fragments of antibodies to neurospecific proteins as carriers for neuroleptic targeted delivery in brain

AbstractA method for targeted delivery of neuroleptics from blood in brain based on using Fab-fragments of antibodies to antigens of brain glia cells (acid gliofibrillar antigen and α2-glycoprotein) is suggested. The essence of the technique is that the molecule of neuroleptic (trifluoperazine) is conjugated with Fab-fragments of these antibodies. The conjugate thus obtained is modified by stearoylchloride in the system of Aerosol OT reversed micelles in octane. The study of the distribution of 125I-labelled conjugates in the rat organism after intracordial introduction is performed. On the contrary to the nonmodified conjugates and conjugate, containing fatty acylated Fab-fragments of antibodies, nonspecific to the rat brain, the conjugate of trifluoperazine with stearoylated Fab-fragments of antibodies to neurospecific antigens accumulate in brain tissues. The drastic increase of the neuroleptic activity of trifluoperazine resulting from its coupling with stearoylated Fab-fragments of antiglial antibodies is observed

Heterogeneous Fluorescence Intermittency in Single Layer Reduced Graphene Oxide

We provide, for the first time, direct experimental evidence for heterogeneous blinking in reduced graphene oxide (rGO) during photolysis. The spatially resolved intermittency originates from regions within individual rGO sheets and shows 1/f-like power spectral density. We describe the evolution of rGO blinking using the multiple recombination center (MRC) model that captures common features of nanoscale blinking. Our results illustrate the universal nature of blinking and suggest a common microscopic origin for the effect

Cryochemical Synthesis of Polymorphous Nanostructures of a Steroid Neurohormone

A new cryochemical strategy of producing nanoparticles and polymorphous nanostructures of drugs is used, which is based on the dynamic combination of high and low temperatures, gas and solid phases, and inert carrier gases. This technology is applied to the synthesis of nanoparticles of steroid neurohormone dehydroepiandrosterone (DHEA). We have optimized the conditions of synthesis of the new polymorphous DHEA structure, FVII. The molecules of DHEA in FVII structure are bound by hydrogen bonds via oxygen atoms. The grain size is 100 nm. It is shown that the yield and ratio of the resulting nanoforms of this hormone are determined by the nature and properties of the inert carrier gas. The highest yield and selectivity of FVII are observed when carbon dioxide is used as the carrier gas. In the case of helium, the FVII content decreases from 85 to 30% and other structures are formed. In experiments without carrier gas, nanoparticles are formed but no FVII is produced. The selectivity and the effect of carrier gas are considered on the basis of homogeneous and heterogeneous formation of nanoparticles and the relationship between particle selectivity and its activity. The synthesis of various polymorphous structures on the nanoscale is assumed to be the manifestation of the size effect in the synthesis of drugs

Allylcytisine as a convenient scaffold for the construction of the π,σ-coordination compound {Acyt(H+)}[Cu8{Acyt(H+)}Cl10] with the unusual anionic 1D-coordination polymer

The aim of this work is to develop a novel π-coordination compound with unusual architecture using allylcytisine (Acyt) as a suitable scaffold. The synthesis and structural characterization of {Acyt(H+)}[Cu8{Acyt(H+)}Cl10] (1) and Acyt itself have been performed, accompanied by quantum chemical studies. A distinctive feature of structure 1 is the formation of H-bonded pairs of two {Acyt(H+)} cations, showing the non-equivalent participation of its allyl group regarding to Cu+ coordination, thus forcing the organization of the acentric structure 1 with the unusually organized anionic copper(I) halide 1D-coordination polymer.peerReviewe

Direct Observation of Single Layer Graphene Oxide Reduction through Spatially Resolved, Single Sheet Absorption/Emission Microscopy

Laser reduction of graphene oxide (GO) offers unique opportunities for the rapid, nonchemical production of graphene. By tuning relevant reduction parameters, the band gap and conductivity of reduced GO can be precisely controlled. In situ monitoring of single layer GO reduction is therefore essential. In this report, we show the direct observation of laser-induced, single layer GO reduction through correlated changes to its absorption and emission. Absorption/emission movies illustrate the initial stages of single layer GO reduction, its transition to reduced-GO (rGO) as well as its subsequent decomposition upon prolonged laser illumination. These studies reveal GO’s photoreduction life cycle and through it native GO/rGO absorption coefficients, their intrasheet distributions as well as their spatial heterogeneities. Extracted absorption coefficients for unreduced GO are α405 nm ≈ 6.5 ± 1.1 × 104 cm–1, α520 nm ≈ 2.1 ± 0.4 × 104 cm–1, and α640 nm ≈ 1.1 ± 0.3 × 104 cm–1 while corresponding rGO α-values are α405 nm ≈ 21.6 ± 0.6 × 104 cm–1, α520 nm ≈ 16.9 ± 0.4 × 104 cm–1, and α640 nm ≈ 14.5 ± 0.4 × 104 cm–1. More importantly, the correlated absorption/emission imaging provides us with unprecedented insight into GO’s underlying photoreduction mechanism, given our ability to spatially resolve its kinetics and to connect local rate constants to activation energies. On a broader level, the developed absorption imaging is general and can be applied toward investigating the optical properties of other two-dimensional materials, especially those that are nonemissive and are invisible to current single molecule optical techniques.Fil: Sokolov, Denis A.. University Of Notre Dame-Indiana; Estados UnidosFil: Morozov, Yurii V.. University Of Notre Dame-Indiana; Estados Unidos. Taras Shevchenko National University of Kiev; RusiaFil: McDonald, Matthew P.. University Of Notre Dame-Indiana; Estados UnidosFil: Vietmeyer, Felix. University Of Notre Dame-Indiana; Estados UnidosFil: Hodak, Jose Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Kuno, Masaru. University Of Notre Dame-Indiana; Estados Unido

Photoluminescence Up-Conversion in CsPbBr₃ Nanocrystals

We report the first observation of phonon-assisted photoluminescence up-conversion from CsPbBr₃ nanocrystals (NCs) at both the ensemble and single-NC levels. Ensemble up-conversion efficiencies are estimated to be on the order of 75% for a Δ<i>E</i> = 23 meV excitation detuning into the nanocrystal gap