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The observation of unexpected polarization textures such as vortices, skyrmions, and merons in various oxide heterostructures has challenged the widely accepted picture of ferroelectric domain walls as being Ising-like. Bloch components in the 180° domain walls of PbTiO_{3} have recently been reported in PbTiO_{3}/SrTiO_{3} superlattices and linked to domain wall chirality. While this opens exciting perspectives, the ubiquity of this Bloch component remains to be further explored. In this work, we present a comprehensive investigation of domain walls in PbTiO_{3}/SrTiO_{3} superlattices, involving a combination of first- and second-principles calculations, phase-field simulations, diffuse scattering calculations, and synchrotron-based diffuse x-ray scattering. Our theoretical calculations highlight that the previously predicted Bloch polarization in the 180° domain walls in PbTiO_{3}/SrTiO_{3} superlattices might be more sensitive to the boundary conditions than initially thought and is not always expected to appear. Employing diffuse scattering calculations for larger systems, we develop a method to probe the complex structure of domain walls in these superlattices via diffuse x-ray scattering measurements. Through this approach, we investigate depolarization-driven ferroelectric polarization rotation at the domain walls. Our experimental findings, consistent with our theoretical predictions for realistic domain periods, do not reveal any signatures of a Bloch component in the centers of the 180° domain walls of PbTiO_{3}/SrTiO_{3} superlattices, suggesting that the precise nature of domain walls in the ultrathin PbTiO_{3} layers is more intricate than previously thought and deserves further attention.

Our previous study shows that the angle of linear polarization (AOLP) of solar radiation that is scattered from clouds at near-backscatter angles can be used to detect super-thin cirrus clouds over oceans. Such clouds are too thin to be sensed using any current passive satellite instruments that only measure light's total intensity, because of the uncertainty in surface reflection. In this report, we show that with a method similar to the super-thin cloud detection algorithm, dust aerosols may also be detected and differentiated from clouds. We also show that the degree of polarization of reflected light can be used for retrieving the optical depth of dust aerosols in the neighborhood of the backscatter angle, regardless of the reflecting surface conditions. This is a simple and robust algorithm, which could be used to survey dust aerosols over midlatitude and tropical oceans.

In recent years, there has been an impressive development of nanotechnology. This has resulted in the increasing release of nanomaterials (NM) into the environment, thereby causing the risk of an uncontrolled impact on living organisms, including plants. More studies indicated the biotoxic effect of NM on plants, including crops. The interaction of nanoparticles (NP) with food crops is extremely important as they are a link to the food chain. The objective of this study was to investigate the effect of negatively charged gold nanoparticles (-) AuNP (at two concentrations; 25 µg/mL or 50 µg/mL) on barley (Hordeum vulgare L.) root development. Morphological, histological and ultrastructural analyses (with the use of stereomicroscope, bright filed microscope and transmission electron microscope) revealed that regardless of the concentration, (-) AuNP did not enter into the plant body. However, the dose of (-) AuNP proved to be important for the plant’s response because different morphological, histological and ultrastructural changes were observed in the treated roots. The NP treatment caused: red root colouration, a local increase in the root diameter and a decreased formation of the root hair cells (on morphological level), damage to the rhizodermal cells, vacuolisation of the cortical cells, a detachment of the cell files between the cortical cells, atypical divisions of the cells, disorder of the meristem organisation (on the histological level), the appearance of periplasmic space, numerous vesicles and multivesicular bodies, electron-dense spots in cytoplasm, alterations in the structure of the mitochondria, breakdown of the tonoplast and the plasmalemma (on the ultrastructural level).

A laser technology for creating nanocomposites from alternating layers of albumin/collagen proteins with two types of single-walled carbon nanotubes (SWCNT) at concentrations of 0.001 and 0.01 wt.% was proposed. For this purpose, a setup with a diode laser (810 nm) and feedback system for controlling the temperature of the area affected by the radiation was developed. Raman spectroscopy was used to determine a decrease in the defectiveness of SWCNT with an increase in their concentration in the nanocomposite due to the formation of branched 3D networks with covalent bonds between nanotubes. It was revealed that adhesion of proteins to branched 3D networks from SWCNT occurred. The specific electrical conductivity of nanocomposites based on large SWCNT nanotubes was 3.2 and 4.3 S/m compared to that for nanocomposites based on small SWCNT with the same concentrations—1.1 and 1.8 S/m. An increase in the concentration and size of nanotubes provides higher porosity of nanocomposites. For small SWCNT-based nanocomposites, a significant number of mesopores up to 50 nm in size and the largest specific surface area and specific pore volume were found. Nanocomposites with small SWCNT (0.001 wt.%) provided the best cardiac fibroblast viability. Such technology can be potentially used to create bioelectronic components or scaffolds for heart tissue engineering.

The article is devoted to the study of losses in devices based on high-temperature superconductors of the 2nd generation. The complexity of the devices under study increases from a single rack coil to a winding assembled from several coils, and finally to an electric machine operating in generator mode. This is the way to experimentally study the behavior of 2nd generation high temperature superconductor (2G HTS) carrying a transport current in various conditions: self-field, external DC, and AC magnetic field. Attention is also paid to the losses in the winding during its operation from the inverter, which simulates the operating conditions in the motor mode of a propulsion system.

We present a detailed study of compressively strained PbxSr1−xTiO3 thin films grown by off-axis radio frequency magnetron sputtering on (001)-oriented Nb-doped SrTiO3 substrates. Film tetragonality and the ferroelectric critical temperatures are measured for samples of different composition and thickness and compared with a phenomenological Landau-Devonshire model. 180∘ ferroelectric domains are observed using both X-ray diffraction and piezoresponse force microscopy and domain sizes obtained by the two techniques are compared and discussed.

Cloud-aerosol interaction is a key issue in the climate system, affecting the water cycle, the weather, and the total energy balance including the spatial and temporal distribution of latent heat release. Information on the vertical distribution of cloud droplet microphysics and thermodynamic phase as a function of temperature or height, can be correlated with details of the aerosol field to provide insight on how these particles are affecting cloud properties and their consequences to cloud lifetime, precipitation, water cycle, and general energy balance. Unfortunately, today's experimental methods still lack the observational tools that can characterize the true evolution of the cloud microphysical, spatial and temporal structure in the cloud droplet scale, and then link these characteristics to environmental factors and properties of the cloud condensation nuclei. Here we propose and demonstrate a new experimental approach (the cloud scanner instrument) that provides the microphysical information missed in current experiments and remote sensing options. Cloud scanner measurements can be performed from aircraft, ground, or satellite by scanning the side of the clouds from the base to the top, providing us with the unique opportunity of obtaining snapshots of the cloud droplet microphysical and thermodynamic states as a function of height and brightness temperature in clouds at several development stages. The brightness temperature profile of the cloud side can be directly associated with the thermodynamic phase of the droplets to provide information on the glaciation temperature as a function of different ambient conditions, aerosol concentration, and type. An aircraft prototype of the cloud scanner was built and flew in a field campaign in Brazil. The CLAIM-3D (3-Dimensional Cloud Aerosol Interaction Mission) satellite concept proposed here combines several techniques to simultaneously measure the vertical profile of cloud microphysics, thermodynamic phase, brightness temperature, and aerosol amount and type in the neighborhood of the clouds. The wide wavelength range, and the use of multi-angle polarization measurements proposed for this mission allow us to estimate the availability and characteristics of aerosol particles acting as cloud condensation nuclei, and their effects on the cloud microphysical structure. These results can provide unprecedented details on the response of cloud droplet microphysics to natural and anthropogenic aerosols in the size scale where the interaction really happens.

Bulk NdNiO3 and thin films grown along the pseudocubic (001)pc axis display a 1st order metal to insulator transition (MIT) together with a Néel transition at T = 200 K. Here, we show that for NdNiO3 films deposited on (111)pc NdGaO3, the MIT occurs at T = 335 K and the Néel transition at T = 230 K. By comparing transport and magnetic properties of layers grown on substrates with different symmetries and lattice parameters, we demonstrate a particularly large tuning when the epitaxy is realized on (111)pc surfaces. We attribute this effect to the specific lattice matching conditions imposed along this direction when using orthorhombic substrates.

Cloud development, the onset of precipitation and the effect of aerosol on clouds depend on the structure of the cloud profiles of droplet size and phase. Aircraft measurements of cloud profiles are limited in their temporal and spatial extent. Satellites were used to observe cloud tops not cloud profiles with vertical profiles of precipitation-sized droplets anticipated from CloudSat. The recently proposed CLAIM-3D satellite mission (cloud aerosol interaction mission in 3-D) suggests to measure profiles of cloud microphysical properties by retrieving them from the solar and infrared radiation reflected or emitted from cloud sides. Inversion of measurements from the cloud sides requires rigorous understanding of the 3-dimentional (3-D) properties of clouds. Here we discuss the reflected sunlight from the cloud sides and top at two wavelengths: one nonabsorbing to solar radiation (0.67 μm) and one with liquid water efficient absorption of solar radiation (2.1 μm). In contrast to the plane-parallel approximation, a conventional approach to all current operational retrievals, 3-D radiative transfer is used for interpreting the observed reflectances. General properties of the radiation reflected from the sides of an isolated cloud are discussed. As a proof of concept, the paper shows a few examples of radiation reflected from cloud fields generated by a simple stochastic cloud model with the prescribed vertically resolved microphysics. To retrieve the information about droplet sizes, we propose to use the probability density function of the droplet size distribution and its first two moments instead of the assumption about fixed values of the droplet effective radius. The retrieval algorithm is based on the Bayesian theorem that combines prior information about cloud structure and microphysics with radiative transfer calculations.

Nickelates are known for their metal to insulator transition (MIT) and an unusual magnetic ordering, occurring at T = TNéel. Here, we investigate thin films of SmNiO3 subjected to different levels of epitaxial strain. We find that the original bulk behavior (TNéel < TMI) is strongly affected by applying compressive strain to the films. For small compressive strains, a regime where TNéel = TMI is achieved, the paramagnetic insulating phase characteristic of the bulk compound is suppressed and the MIT becomes 1st order. Further increasing the in-plane compression of the SmNiO3 lattice leads to the stabilization of a single metallic paramagnetic phase.