On the adsorption and reactivity of element 114, flerovium.

Flerovium (Fl, element 114) is the heaviest element chemically studied so far. To date, its interaction with gold was investigated in two gas-solid chromatography experiments, which reported two different types of interaction, however, each based on the level of a few registered atoms only. Whereas noble-gas-like properties were suggested from the first experiment, the second one pointed at a volatile-metal-like character.

An Insight into the Correlation between Chemical Composition Changes of Aluminum-Iron-Polyphosphate Glasses and Thermal Properties.

The present study aimed to investigate the influence of the gradual substitution of FeO by AlO on the thermal properties of polyphosphate glasses. The conducted considerations based on differential scanning calorimetry (DSC) and heating microscopy thermal analysis provided much essential information about the correlation between glass chemical composition and its characteristic parameters, such as transformation temperature, specific heat, crystallization temperature, crystallization enthalpy, the activation energy of crystal growth, melting temperature, and Angell glass thermal stability. The obtained estimation of viscosity changes as a function of temperature could be very helpful for researchers to correctly plan the vitrification process and thus radioactive waste immobilization.

Rapid Assessment of SARS-CoV-2 Transmission Risk for Fecally Contaminated River Water.

Following the outbreak of severe acute respiratory syndrome coronavirus (SARS-CoV-2), airborne water droplets have been identified as the main transmission route. Identifying and breaking all viable transmission routes are critical to stop future outbreaks, and the potential of transmission by water has been highlighted. By modifying established approaches, we provide a method for the rapid assessment of the risk of transmission posed by fecally contaminated river water and give example results for 39 countries.

Low-frequency electromagnetic field influences human oral mucosa keratinocyte viability in response to lipopolysaccharide or minocycline treatment in cell culture conditions.

The aim of the current study was to investigate the influence of low-frequency electromagnetic field (LF-EMF) exposure on viability parameters of oral mucosa keratinocytes cultured in in vitro conditions. The effect of LF-EMF stimulation on cell viability was also specified in the simultaneous presence of lipopolysaccharide (LPS) infectious agent or minocycline (Mino) anti-inflammatory agent. Viability parameters such as early-, late apoptosis and necrosis of keratinocytes were analysed by the flow cytometry method (FCM).

Surface Photochemical Corrosion as a Mechanism for Fast Degradation of InGaN UV Laser Diodes.

We studied degradation mechanisms of ultraviolet InGaN laser diodes emitting in the UVA range. Short wavelength nitride devices are subjected to much faster degradation, under the same packaging and testing conditions, than their longer wavelength counterparts. Transmission electron microscopy analysis of the degraded laser diodes showed pronounced damage to facets in the area of the active layer (waveguide, quantum wells, and electron blocking layer).

Contactless Measurements of Carrier Concentrations in InGaAs Layers for Utilizing in InP-Based Quantum Cascade Lasers by Employing Optical Spectroscopy.

The precise determination of carrier concentration in doped semiconductor materials and nanostructures is of high importance. Many parameters of an operational device are dependent on the proper carrier concentration or its distribution in both the active area as well as in the passive parts as the waveguide claddings. Determining those in a nondestructive manner is, on the one hand, demanded for the fabrication process efficiency, but on the other, challenging experimentally, especially for complex multilayer systems.

Microstructure Influence of SACX0307-TiO Composite Solder Joints on Thermal Properties of Power LED Assemblies.

The effect of the microstructure of solder joints on the thermal properties of power LEDs is investigated. Solder joints were prepared with different solder pastes, namely 99Sn0.3Ag0.

Effect of Recrystallization on β to α-Sn Allotropic Transition in 99.3Sn-0.7Cu wt. % Solder Alloy Inoculated with InSb.

The effect of recrystallization of 99.3Sn-0.7Cu wt.

Selective area formation of GaN nanowires on GaN substrates by the use of amorphous Al O nucleation layer.

Examples are presented that application of amorphous Al O nucleation layer is an efficient way of controlling spatial distribution of GaN nanowires grown by plasma-assisted molecular beam epitaxy. On GaN/sapphire substrates Al O stripes induce formation of GaN nanowires while a compact GaN layer is formed outside the stripes. We show that the ratio of nanowire length h to the thickness of the compact layer d can be tailored by adjusting impinging gallium and nitrogen fluxes.

Microscopic investigations of morphology and thermal properties of ZnO thin films grown by atomic layer deposition method.

This work presents the study of morphology and thermal properties of thin ZnO films fabricated by atomic layer deposition. The layers were deposited on n-Si(100) wafers at 200 °C. X-ray diffraction measurements showed the polycrystalline structure of the thin films with preferred (100) orientation.

Local atomic order of the amorphous TaO thin films in relation to their chemical resistivity.

The experimental and theoretical studies of the local atomic order and chemical binding in tantalum oxide amorphous films are presented. The experimental studies were performed on thin films deposited at the temperature of 100 °C by atomic layer deposition on silicon (100) and glass substrates. Thin films of amorphous tantalum oxide are known to exhibit an extremely large extent of oxygen nonstoichiometry.

Piezoelectric Films Based on Polyethylene Modified by Aluminosilicate Filler.

The development, universality and miniaturization of electronic devices leads to the search for new piezoelectric materials, among which recently, polymers play an increasingly important role. In this work, composites based on two types of polyethylene-high density polyethylene (HDPE), and medium density polyethylene (MDPE)-and aluminosilicate fillers were obtained by extrusion process. This method allowed obtaining flexible electrets in the form of a thin film after polarization under a constant electric field of 100 V/μm.

Quantitative Analysis of Foot Plantar Pressure During Walking.

BACKGROUND There are many methods of dynamic analysis of foot loading, however, we still need a simple, easily applicable system for foot plantar pressure analysis. In this study we asked the question: "Can a new system for foot evaluation, the ITE System, provide a good quantitative dynamic foot pressure analysis? Can it be used in clinical practice?". MATERIAL AND METHODS Twenty healthy volunteers, 8 females and 12 males, aged 20 to 25 years old took part in this study.

Optimization of MBE Growth Conditions of InAlAs Waveguide Layers for InGaAs/InAlAs/InP Quantum Cascade Lasers.

We investigate molecular beam epitaxy (MBE) growth conditions of micrometers-thick InAlAs designed for waveguide of InGaAs/InAlAs/InP quantum cascade lasers. The effects of growth temperature and V/III ratio on the surface morphology and defect structure were studied. The growth conditions which were developed for the growth of cascaded InGaAs/InAlAs active region, e.

Damage-induced voltage alteration (DIVA) contrast in SEM images of ion-irradiated semiconductors.

The ion-irradiation damage effects in semiconductors were directly visualized by means of scanning electron microscopy at low beam acceleration voltages (low-kV SEM). The AlGaAs (p-type and n-type) epitaxial layers grown over GaAs substrates were irradiated with energetic He ions with fluencies ranging from 8e12 to 8e13 cm and studied in cross-sectional view after cleavage. Secondary electron images collected at low energy (0.

Ultrasensitive tantalum oxide nano-coated long-period gratings for detection of various biological targets.

In this work we discussed a label-free biosensing application of long-period gratings (LPGs) optimized in refractive index (RI) sensitivity by deposition of thin tantalum oxide (TaO) overlays. Comparing to other thin film and materials already applied for maximizing the RI sensitivity, TaO offers good chemical and mechanical stability during its surface functionalization and other biosensing experiments. It was shown theoretically and experimentally that when RI of the overlay is as high as 2 in IR spectral range, for obtaining LPGs ultrasensitive to RI, the overlay's thickness must be determined with subnanometer precision.

AlGaN/GaN High Electron Mobility Transistors on Semi-Insulating Ammono-GaN Substrates with Regrown Ohmic Contacts.

AlGaN/GaN high electron mobility transistors on semi-insulating bulk ammonothermal GaN have been investigated. By application of regrown ohmic contacts, the problem with obtaining low resistance ohmic contacts to low-dislocation high electron mobility transistor (HEMT) structures was solved. The maximum output current was about 1 A/mm and contact resistances was in the range of 0.

A Novel Type Room Temperature Surface Photovoltage Gas Sensor Device.

In this paper a novel type of a highly sensitive gas sensor device based on the surface photovoltage effect is described. It is based on the Kelvin probe approach. Porous ZnO nanostructured thin films deposited by the direct current (DC) reactive magnetron sputtering method are used as the active gas sensing electrode material.

Multifrequency Kelvin probe force microscopy on self assembled molecular layers and quantitative assessment of images' quality.

The application of single-pass multifrequency Kelvin probe force microscopy (KPFM) for topography and contact potential difference (CPD) measurements of organic self-assembled monolayers (SAM) is demonstrated. Four modes of mechanical and electrical cantilever excitation were tested in order to obtain the best possible resolution in the CPD measurements. The algorithm using maximum capacity of information channel for quantitative image quality assessment was proposed to compare and assess the quality of the recorded images and imaging modes.

Optimal Design of Electromagnetically Actuated MEMS Cantilevers.

In this paper we present the numerical and experimental results of a design optimization of electromagnetic cantilevers. In particular, a cost-effective technique of evolutionary computing enabling the simultaneous minimization of multiple criteria is applied. A set of optimal solutions are subsequently fabricated and measured.

Mechanical and Physicochemical Properties of Newly Formed ZnO-PMMA Nanocomposites for Denture Bases.

Aim: The aim of this study was to investigate the selected properties of zinc oxide- polymethyl methacrylate (ZnO-PMMA) nanocomposites that can influence the microorganism deposition on their surface.

Materials And Methods: Non-commercial ZnO-NPs were prepared, characterized and used for the preparation of PMMA nanocomposite. Roughness, absorbability, contact angle and hardness of this new nanomaterial were evaluated.

Surface Properties of Nanostructured, Porous ZnO Thin Films Prepared by Direct Current Reactive Magnetron Sputtering.

In this paper, the results of detailed X-ray photoelectron spectroscopy (XPS) studies combined with atomic force microscopy (AFM) investigation concerning the local surface chemistry and morphology of nanostructured ZnO thin films are presented. They have been deposited by direct current (DC) reactive magnetron sputtering under variable absolute Ar/O₂ flows (in sccm): 3:0.3; 8:0.

Contact atomic force microscopy using piezoresistive cantilevers in load force modulation mode.

Scanning probe microscopy (SPM) encompasses several techniques for imaging of the physical and chemical material properties at nanoscale. The scanning process is based on the detection of the deflection of the cantilever, which is caused by near field interactions, while the tip runs over the sample's surface. The variety of deflection detection methods including optical, piezoresistive, piezoelectric technologies has been developed and applied depending on the measurement mode and measurement environment.

Changes in viability of rat adipose-derived stem cells isolated from abdominal/perinuclear adipose tissue stimulated with pulsed electromagnetic field.

Previous experiments demonstrated that low-frequency electromagnetic field (LF-EMF) may activate cellular death pathways in proliferating cells. Therefore, we hypothesized that LF-EMF may also influence viability of highly proliferating undifferentiated adipose-derived stem cells. Obesity is classified as a civilization disease; its etiopathogenesis is presumed to include both genetic predisposition and influence of modified environmental factors, such as unbalanced diet with excess calories and/or too low physical activity.

Highly transparent supercapacitors based on ZnO/MnO nanostructures.

The recent rapid development of transparent electronics, notably displays and control circuits, requires the development of highly transparent energy storage devices, such as supercapacitors. The devices reported to date utilize carbon-based electrodes for high performance, however at the cost of their low transparency around 50%, insufficient for real transparent devices. To overcome this obstacle, in this communication highly transparent supercapacitors were fabricated based on ZnO/MnO nanostructured electrodes.