Ytterbium 10-carboxyperylene-3,4,9-tricarboxylates for targeted NIR luminescent bioimaging.

Two new ytterbium coordination compounds Yb(HPTC)(HO) (Yb1) and Yb(HPTC)(Phen) (Yb2) were obtained using 10-carboxyperylene-3,4,9-tricarboxylate ion (HPTC) as a sensitizer. Both coordination compounds exhibited intense NIR-II luminescence upon excitation in the visible range and formed stable suspensions with nanoparticles of 50-70 nm in size in an aqueous solution of sodium alginate. Both complexes demonstrated non-toxicity up to at least 25 mg L in two cell cultures: cancer cells MCF7 and embryonic cells HEK293T - making them suitable for bioimaging.

Tunable Sieving of Ions Using Graphene Oxide: Swelling Peculiarities in Free-Standing and Confined States.

The paper describes a comparative study of swelling processes in free-standing graphene oxide (GO) membranes and GO laminates encapsulated with epoxy glue. For free-standing graphene oxide membranes, a huge variation in -spacing in the range of 8-12 Å depending on the ambient humidity and from 12 to >30 Å depending on the electrolyte type and its concentration was revealed using direct and XRD studies. Limited swelling at various humidity levels as well as in electrolyte solution with low constriction/expansion of epoxy-encapsulated GO is counterposed to that of free-standing graphene oxides.

Nanoceramics of metastable ε-FeO: effect of sintering on the magnetic properties and sub-terahertz electron resonance.

In this study, we demonstrate the sintering of metastable ε-FeO nanoparticles into nanoceramics containing 98 wt% of the epsilon iron oxide phase and with a specific density of 60%. At room temperature, the ceramics retain a giant coercivity of 20 kOe and a sub-terahertz absorption at 190 GHz inherent in the initial nanoparticles. The sintering leads to an increase in the frequencies of the natural ferromagnetic resonance at 200-300 K and larger coercivities at temperatures below 150 K.

Pulse Power Generation Chronoamperometry as an Advanced Readout for (Bio)sensors: Application for Noninvasive Diabetes Monitoring.

We propose pulse power generation (PPG) amperometry as an advanced readout realized for Prussian blue (PB)-based (bio)sensors. In contrast to the conventional power generation mode, when the current response is generated upon continuous short-circuiting, the suggested pulse regime is fulfilled by periodic opening and shorting of the circuit. Despite PB being electroactive, the pulse readout is advantageous over conventional steady-state power generation, providing up to a 15-fold increased signal-to-background ratio as well as dramatically improved sensitivity exceeding 10 A·M·cm for HO sensors and 3.

Dimeric and 1D polymeric low-chlorinated C fullerenes, (CCl) and (CCl).

Low-chlorinated fullerenes, dimeric (CCl) and one-dimensional, polymeric (CCl), were obtained by high-temperature (270 °C) chlorination of C with a SbCl/SbCl mixture, as revealed by X-ray crystallography. The compounds were characterized by IR and Raman spectroscopy and theoretical calculations. This is the first observation of a fullerene polymer with single C-C bonding and neutral building blocks.

Mass transport limitations for electrochemical sensing in low-flux excretory fluids.

Despite non-invasive instant monitoring of sweat metabolites is becoming a general trend in early diagnostics and screening, the reliability and accuracy of the on-skin electrochemical biosensors in real-life scenarios still remain questionable. As a rule, mass transport effects in scantily excreted liquids are ignored, when considering the design of such wearable setups. Here we provide a comprehensive investigation of the disruption factors for commonly used Prussian Blue based (bio)sensors under different hydrodynamic conditions (2 × 10 - 5 × 10 mm s electrolyte velocity).

Influence of heat transfer and wetting angle on condensable fluid flow through nanoporous anodic alumina membranes.

The flow of isobutane and of freon 142b (1-chloro-1,1-difluoro-ethane) through anodic alumina membranes with pore diameters between 18 and 60 nm in a capillary condensation regime is experimentally and theoretically explored. The capillary condensation effect increases the membrane permeance for condensable gases from 25 to 150 m(STP) m bar h at certain conditions. To describe the experimental results, a model is suggested accounting for heat transfer from the condensing to the evaporating meniscus, different boundary conditions for the heat transfer between the environment and the membrane, and wettability of the pore wall.

The Anatase-to-Rutile Phase Transition in Highly Oriented Nanoparticles Array of Titania with Photocatalytic Response Changes.

An array of highly oriented anatase nanoparticles was successfully prepared from NHTiOF with the assistance of polyetheleneglycol-400 at 450 °C. The study showed the stability of obtained layered TiO-anatase close to 1200 °C. This research confirmed for the first time that the transition of mesocrystalline anatase to the rutile phase occurs between 1000 °C and 1200 °C, which is more than 400 °C higher than the transition of bulk TiO due to the used precursor.

Light Response and Switching Behavior of Graphene Oxide Membranes Modified with Azobenzene Compounds.

Here, we report on the fabrication of light-switchable and light-responsive membranes based on graphene oxide (GO) modified with azobenzene compounds. Azobenzene and -aminoazobenzene were grafted onto graphene oxide layers by covalent attachment/condensation reaction prior to the membranes' assembly. The modification of GO was proven by the UV-vis, IR, Raman and photoelectron spectroscopy.

Oxidized Carbon-Based Spacers for Pressure-Resistant Graphene Oxide Membranes.

In this study, we report the influence of carbon-based spacer-oxidized derivatives of fullerenes (fullerenols) C60(OH)26−32 and graphene oxide nanoribbons on the performance and pressure stability of graphene-oxide-based composite membranes. The impact of the intercalant shape and composition on the permeance of the selective layers for water vapors has been studied under pressure gradients. It is shown that the insertion of ball-shaped fullerenols between graphene oxide nanoflakes allows a suppression in irreversible permeance loss to 2−4.

Gradient Structure of the Transfer Layer in Friction Stir Welding Joints.

Despite a thirty-year history of friction stir welding, some basic aspects still remain unclear. In particular, questions arise about mass transfer and the formation of transfer layers. It is not clear why there are visible boundaries between the layers.

Simultaneous monitoring of sweat lactate content and sweat secretion rate by wearable remote biosensors.

We report on the simultaneous monitoring of sweat lactate concentration and sweat secretion rate. For this aim lactate oxidase-Prussian Blue enzyme-nanozyme type lactate biosensors were elaborated. The use of siloxane-perfluorosulfonated ionomer composite membrane for enzyme-nanozyme immobilization results in the biosensor displaying flux independence in the whole range of physiological sweat secretion rates (0.

Sagittal Balance Parameters after Anterior Cervical Discectomy with Spondylodesis and Arthroplasty Using Endocarbon Endoprosthesis: Results of Randomized Study.

Unlabelled: was to examine the effect of cervical segment mobility on spinal sagittal balance parameters after cervical total disc arthroplasty (CTDA) and anterior cervical discectomy and fusion (ACDF) using the first domestic intervertebral disc endoprosthesis.

Materials And Methods: The randomized prospective study included 98 patients (48 with CTDA, 50 with ACDF). Implants used: intervertebral disc endoprosthesis or intervertebral fusion cage (Endocarbon; NPP "MedInzh", Russia).

Surface-Enhanced Raman Scattering-Active Gold-Decorated Silicon Nanowire Substrates for Label-Free Detection of Bilirubin.

Bilirubin (BR) is a product of hemoglobin breakdown, and its increasing levels in the blood may indicate liver disorders and lead to jaundice. Kernicterus is most dangerous in newborns when the unconjugated BR concentration can quickly rise to toxic levels, causing neurological damage and even death. The development of an accurate, fast, and sensitive sensor for BR detection will help reduce diagnostic time and ensure successful treatment.

One-step synthesis of vanadium-doped anatase mesocrystals for Li-ion battery anodes.

Here we report a successful one-step synthesis of vanadium-doped anatase mesocrystals by reactive annealing of NHTiOF/PEG2000 mesocrystal precursors with NHVO. The formation solid solution TiVOwith vanadium content up to = 25 at% inheriting the structure of mesocrystals is observed for the first time. The doping mechanism via vapor phase transport of vanadium is proposed.

Mass flow and momentum flux in nanoporous membranes in the transitional flow region.

An experimental study of momentum transfer in nanoporous polymeric track-etched membranes with pore diameters ranging from 100 to 1300 nm and nanochannel lengths of 12-20 μm was performed using He, N, CO, and SF propellants in a wide range of plenum and background pressures. Mass flux through the membranes was elaborated as a combination of Knudsen diffusion and viscous flow at Knudsen numbers above 0.1 and become choked at lower Knudsen numbers.

Core-Shell Nanozymes "Artificial Peroxidase": Stability with Superior Catalytic Properties.

We report on the nanoparticles composed of the catalytically synthesized Prussian Blue (PB) core stabilized with the nickel hexacyanoferrate (NiHCF) shell. Catalyzing hydrogen peroxide reduction, the resulting nanozymes (ø = 66 nm) display catalytic rate constants, which for pyrogallol or ferrocyanide are, respectively, 25 and 35 times higher than those for peroxidase enzyme. After more than half a year of storage at a room temperature, the core-shell PB-NiHCF nanozymes retain both their size and physicochemical properties; such stability is unreachable for the enzymes.

Glass-Ceramic Synthesis of Cr-Substituted Strontium Hexaferrite Nanoparticles with Enhanced Coercivity.

Magnetically hard ferrites attract considerable interest due to their ability to maintain a high coercivity of nanosized particles and therefore show promising applications as nanomagnets ranging from magnetic recording to biomedicine. Herein, we report an approach to prepare nonsintered single-domain nanoparticles of chromium-substituted hexaferrite via crystallization of glass in the system SrO-FeO-CrO-BO. We have observed a formation of plate-like hexaferrite nanoparticles with diameters changing from 20 to 190 nm depending on the annealing temperature.

PyRad: A software shell for simulating radiolysis with Qball package.

The assessment of the radiolytic stability of media is an important task in the fields of nuclear power engineering and radiochemistry. Such studies must be carried out in special laboratory conditions with the use of sources of ionizing radiation, which may increase personal doses of the staff. In addition, difficulties arise in studying the products of irradiated media.

Tb-based silicate apatites showing slow magnetization relaxation with identical parameters for the Tb and Dy counter ions.

Tb-diluted and Tb-rich apatite-type silicates with compositions YTbCa(SiO)O and TbCa(SiO)O, respectively, exhibit field induced multiple slow relaxation of magnetization. The former reveals two slow relaxation paths, the latter only one with a longer relaxation time of several seconds. The relaxation features of the Tb-diluted one are comparable with those of analogue compounds, where Tb is replaced by Dy, as well as with those of a Tb-doped calcium phosphate apatite.

Application of 2D Gait Analysis for the Assessment of Gait Disturbance in Patients with Spastic Tetraparesis.

Unlabelled: was to explore the use of 2D gait analysis for assessing gait abnormalities in patients with spastic tetraparesis associated with spinal cord injury and other lesions of the cervical spinal cord.

Materials And Methods: The study included 12 patients with tetraparesis of various etiologies. Gait assessment was performed by video analysis using reflective markers (1.

Spray-Deposited Anisotropic Ferromagnetic Hybrid Polymer Films of PS--PMMA and Strontium Hexaferrite Magnetic Nanoplatelets.

Spray deposition is a scalable and cost-effective technique for the fabrication of magnetic hybrid films containing diblock copolymers (DBCs) and magnetic nanoparticles. However, it is challenging to obtain spray-deposited anisotropic magnetic hybrid films without using external magnetic fields. In the present work, spray deposition is applied to prepare perpendicular anisotropic magnetic hybrid films by controlling the orientation of strontium hexaferrite nanoplatelets inside ultra-high-molecular-weight DBC polystyrene--poly(methyl methacrylate) (PS--PMMA) films.

Fabrication of antireflection microstructures on the surface of GaSe crystal by single-pulse femtosecond laser ablation.

GaSe crystals are promising as nonlinear optical converters in the mid- and far-IR ranges. However, it is challenging to increase the GaSe surface transmittance of 77% with conventional antireflection coatings because of poor surface quality, leading to coating adhesion problems. Antireflection microstructures (ARMs) offer an alternative way of increasing surface transmittance.

Anodic alumina membrane capacitive sensors for detection of vapors.

Here we report membrane capacitive sensors based on anodic aluminum oxide (AAO) Au/AAO/Au structures fabricated by aluminum anodization, followed by gold electrodes sputtering on the countersides of porous ceramic membrane. Electrochemical impedance spectroscopy with AC amplitude 5-100 mV in the frequency range of 1-1000 Hz was utilized for sensor characterization in the presence of water and organic vapors in a full range of P/P. The sensors illustrate ultimate sensitivity to ambient environment with exponential-scale capacitance relation to vapors content resulting in typical 4-6 orders of magnitude response signal change for 15-85% P/P range at a single AC frequency, and up to 7 orders of magnitude response range for 0-100% P/P pressure range with using two different AC frequencies.

Bismuth nanowires: electrochemical fabrication, structural features, and transport properties.

Electrochemical aspects of Bi electrocrystallization from a bath containing bismuth nitrate in a mixture of ethylene glycol and water are addressed. Bismuth nanowires with diameters of 50-120 nm and a length of up to a few dozen microns were prepared by electrodeposition into the pores of anodic aluminium oxide templates. Crystal structure and morphology of electrodeposited materials were characterized using electron microscopy, selected area electron diffraction, and X-ray diffraction analysis.