Geometric Anisotropy Research Articles

Insight into the effect of terminal aromatic group on the mesomorphic, emissive and stimuli-responsive properties of cyanostyrene-based derivatives with multiple applications

Three novel series of cyanostyrene-based derivatives containing pyridine, cyanostyrene and terminal phenyl, naphthyl and anthryl as π-conjugated aromatic unit were synthesized by Suzuki coupling and Knoevenagel reactions. A slight modification in chemical structures induced significant differences in self-assembly property in bulk state, emissive properties in both solution and aggregated states, mechanochromic properties and acidochromism properties. The terminal phenyl cyanostyrene-based derivatives exhibited a mesophase transition from nematic phase to smectic A phase upon elongation of the terminal chain and decreasing temperature, whereas the other terminal naphthyl and anthryl cyanostyrene-based derivatives were non-mesogen, which might be attributed to the increased twisted molecular configuration and geometric anisotropy. All the compounds displayed positive solvatochromic behaviors and the redshift in emission spectra gradually increased from terminal naphthyl compound via phenyl compound to anthryl compound attributing to the enhancement in intramolecular charge transfer. All the compounds displayed emission in both solution and aggregated states due to the twisted molecular configurations or/and distinct intramolecular charge transfer. The terminal phenyl and naphthyl compounds displayed extremely weak mechanochromism, whereas the terminal anthryl compound displayed distinct mechanochromism due to the highly twisted molecular configuration of the anthryl compound. Reversible high-contrast acidochromism was realized for all the compounds due to the reversible protonation and deprotonation process of pyridine. In addition, the good applications in security paper, encrypted ink and bioimaging were also demonstrated. This investigation elucidates that a slight change in chemical structures could induce big differences in characteristics in different states, which afforded effective ways for the construction of multifunctional materials.

Measurement of anisotropic airflow resistance characteristics of mineral wool samples

In the field of acoustics, the airflow resistance of a porous materials like stone wool is one of the governing parameters. As a starting point, measuring the airflow resistance in the normal direction can be used for good estimations of sound-absorbing abilities when using empirical models. However, more complex models, like equivalent fluid models and Biot models, need more input parameters. The next natural step is to move into 2D and 3D interactions. An obstacle to overcome is obtaining accurate input parameters to qualify the models. The production process of stone wool introduces an inherent geometric anisotropy in the material. The aim of the study is hence to develop test and sample preparation methods that enable the measurement of the airflow resistance of stone wool sample in 3 directions by means of testing a cubic specimen. The airflow resistance was measured using a modified unidirectional static airflow apparatus. The paper presents test results obtained with the apparatus for a range of stone wool samples of varying densities. The results show noticeable differences in airflow resistance of more than 1.5 times between testing directions. This paper also, includes comparisons to results obtained using an alternating airflow method as per ISO 9053-2:2020.

Reordering of point-vortex lattices under anisotropic diffraction: far-field analysis

Abstract A study of the far-field complex amplitude obtained from initially ordered arrays of N × M point-vortices with equal unitary topological charge embedded in carrier beams with different geometry is presented. This can be understood as the final stationary configuration after the dynamical evolution of the vortices upon propagation, and our aim is to investigate the impact of a geometric anisotropy on the diffraction process by using an elliptic Gaussian beam as a carrier and a rectangular vortex lattice. For comparison, illumination by a circular Gaussian beam and a plane wave diffracted by a rectangular aperture are also analyzed. We show that vortices tend to cluster in some regions under high eccentricity of the carrier and there can be an entire redistribution of the vortices depending on the size of the initial array with respect to the size of the carrier, which inherits some geometric characteristics of the latter.

Anisotropic mechanics of cell-elongated structures: Finite element study based on a 3D cellular model

Cell-elongated structures present designable anisotropic behaviors by controlling the ratio and angle of elongation, but the relationship between geometric anisotropy and mechanical anisotropy remains poorly understood. In this study, a construction method based on the 3D Voronoi technique is employed to generate cell-elongated structures with different elongation ratios and angles, and their anisotropic compression behaviors are investigated using a 3D cellular model. The stress–strain curves can be categorized into four stages, including elasticity, initial collapse followed by strain-softening, plateau, and densification, which are accurately described by a statistical constitutive model. Our finding reveals that the mechanical properties and deformation modes of the cell-elongated structures are significantly influenced by the anisotropic angle. At an anisotropic angle of 0°, randomly distributed collapse bands due to shell buckling interact with each other during compression, enhancing the load-carrying and energy-absorbing capacities. Conversely, at 90°, the cells deform primarily through a stable bending mode, leading to reduced stress and a lower Poisson’s ratio. At 45°, collapse bands appear on both sides of the sample with rotation and buckling being the dominant deformation mode, resulting in a sandwich-like structure featuring an uncollapsed central zone due to a combined compression–shear stress state. Compared with the isotropic foam, the structure elongated in thickness direction exhibits a notable increase in impact resistance under a spherical bullet. This work demonstrates the potential to engineer anisotropic cellular materials with tailored mechanical properties and deformation modes through strategic geometric anisotropy design.

Thermal characterization methodology for thin bond-line interfaces with high conductive materials

Silver sintering offers a promising landscape for Pb-free die attachment in electronics packaging. However, the sintered interface properties are highly process-dependent and deviate from bulk silver properties. Conventional measurement methods do not adequately capture the die-attach application geometry. Hence, this study introduces a novel methodology for characterizing thin bond-line interfaces with high-conductive materials. The transient heat flux impedance ΔZth(t, Δx) was measured between two thermally sensitive devices interconnected using pressureless Ag-sintering material. A correction factor was derived, based on thermal half-space principles, to account for non-uniform heat spreading over the die-attach interface. Experimental findings estimate an effective conductivity of ∼115W/mk for the pressureless Ag-sintered interface. The measurement results were validated by measuring a SAC305 soldered interface, which exhibited ∼55 W/mK, and a non-conductive epoxy interface of ∼2.5 W/mK. Voids on the die-attach layer, resulting from material processing, were identified to influence the interface thermal behavior. An uncertainty analysis was further discussed, emphasizing equipment tolerances, measurement sensitivity, and geometrical and thermal anisotropies. The article concludes with a comparative summary of the proposed methodology against conventional methods, highlighting differences in working principle, thickness range, measurement parameters, and their advantages and limitations.

Hydrogeologic Framework Model‐Based Numerical Simulation of Groundwater Flow and Salt Transport and Analytic Hierarchy Process‐Based Multi‐Criteria Evaluation of Optimal Pumping Location and Rate for Mitigation of Seawater Intrusion in a Complex Coastal Aquifer System

AbstractA series of hydrogeologic framework model (HFM)‐based steady‐ and transient‐state numerical simulations is performed first using a coupled subsurface flow‐transport numerical model to analyze groundwater flow and salt transport in an actual three‐dimensional complex coastal aquifer system before and during groundwater pumping. A series of analytic hierarchy process (AHP)‐based multi‐criteria evaluations is then performed applying a multi‐criteria decision‐making approach to determine optimal pumping location and rate for a new pumping well in the complex coastal aquifer system during groundwater pumping. The complex coastal aquifer system is composed of six anisotropic fractured porous geologic media (five rock formations and one fault) and three isotropic porous geologic media (three soil formations) and shows high geometric irregularity and significant heterogeneity and anisotropy of the nine geologic media. Results of the steady‐state numerical simulations show successful model calibration with 26 measured groundwater levels and two observed seawater intrusion front lines. The latter two are determined by spatial interpolation and extrapolation of electrical conductivity logging data and electrical resistivity survey data, respectively. Based on the status and prospect of necessary water uses and available groundwater resources, the field observations of groundwater and seawater intrusion, and the analyses of the steady‐state numerical simulation after the model calibration, six candidate pumping locations are selected for the new pumping well. In addition, from six preliminary individual transient‐state numerical simulations, maximum pumping rates at the six candidate pumping locations are calculated first, and a set of six incremental candidate pumping rates is then assigned at each of the six candidate pumping locations. Results of the transients‐state numerical simulations show that groundwater flow and salt transport are spatially and temporally changed, and seawater intrusion is further intensified by groundwater pumping. In addition, the magnitudes of such spatial and temporal changes and intensification are significantly different depending on the candidate pumping locations and rates. Results of the steady‐ and transient‐state numerical simulations also show that both complexity (geometric irregularity, heterogeneity, and anisotropy including the fault) and topography have significant effects on the spatial distributions and temporal changes of groundwater flow and salt transport in the coastal aquifer system before and during groundwater pumping. In addition, results of statistical estimations of the mesh Peclet and Courant numbers confirm acceptabilities of minimizing numerical dispersion in the steady‐ and transient‐state numerical simulations. Based on the analyses of the transient‐state numerical simulations, eight multiple criteria are chosen to judge, prioritize, and rank the six candidate pumping locations and six candidate pumping rates for optimal pumping. Results of the multi‐criteria evaluations determine the optimal pumping location and rate for the new pumping well among the six candidate pumping locations and six candidate pumping rates. In addition, results of consistency checks confirm consistencies of judgments in the multi‐criteria evaluations.

Highly Ordered Nanoassemblies of Janus Spherocylindrical Nanoparticles Adhering to Lipid Vesicles.

In recent years, there has been a heightened interest in the self-assembly of nanoparticles (NPs) that is mediated by their adsorption onto lipid membranes. The interplay between the adhesive energy of NPs on a lipid membrane and the membrane's curvature energy causes it to wrap around the NPs. This results in an interesting membrane curvature-mediated interaction, which can lead to the self-assembly of NPs on lipid membranes. Recent studies have demonstrated that Janus spherical NPs, which adhere to lipid vesicles, can self-assemble into well-ordered nanoclusters with various geometries, including a few Platonic solids. The present study explores the additional effect of geometric anisotropy on the self-assembly of Janus NPs on lipid vesicles. Specifically, the current study utilized extensive molecular dynamics simulations to investigate the arrangement of Janus spherocylindrical NPs on lipid vesicles. We found that the additional geometric anisotropy significantly expands the range of NPs' self-assemblies on lipid vesicles. The specific geometries of the resulting nanoclusters depend on several factors, including the number of Janus spherocylindrical NPs adhering to the vesicle and their aspect ratio. The lipid membrane-mediated self-assembly of NPs, demonstrated by this work, provides an alternative cost-effective route for fabricating highly engineered nanoclusters in three dimensions. Such structures, with the current wide range of material choices, have great potential for advanced applications, including biosensing, bioimaging, drug delivery, nanomechanics, and nanophotonics.

A microstructure-based parameterization of the effective anisotropic elasticity tensor of snow, firn, and bubbly ice

Abstract. Quantifying the link between microstructure and effective elastic properties of snow, firn, and bubbly ice is essential for many applications in cryospheric sciences. The microstructure of snow and ice can be characterized by different types of fabrics (crystallographic and geometrical), which give rise to macroscopically anisotropic elastic behavior. While the impact of the crystallographic fabric has been extensively studied in deep firn, the present work investigates the influence of the geometrical fabric over the entire range of possible volume fractions. To this end, we have computed the effective elasticity tensor of snow, firn, and ice by finite-element simulations based on 391 X-ray tomography images comprising samples from the laboratory, the Alps, Greenland, and Antarctica. We employed a variant of Eshelby's tensor that has been previously utilized for the parameterization of thermal and dielectric properties of snow and utilized Hashin–Shtrikman bounds to capture the nonlinear interplay between density and geometrical anisotropy. From that we derive a closed-form parameterization for all components of the (transverse isotropic) elasticity tensor for all volume fractions using two fit parameters per tensor component. Finally, we used the Thomsen parameter to compare the geometrical anisotropy to the maximal theoretical crystallographic anisotropy in bubbly ice. While the geometrical anisotropy clearly dominates up to ice volume fractions of ϕ≈0.7, a thorough understanding of elasticity in bubbly ice may require a coupled elastic theory that includes geometrical and crystallographic anisotropy.

An inorganic liquid crystalline dispersion with 2D ferroelectric moieties.

Electro-optical effect-based liquid crystal devices have been extensively used in optical modulation techniques, in which the Kerr coefficient reflects the sensitivity of the liquid crystals and determines the strength of the device's operational electric field. The Peterlin-Stuart theory and the O'Konski model jointly indicate that a giant Kerr coefficient could be obtained in a material with both a large geometrical anisotropy and an intrinsic polarization, but such a material is not yet reported. Here we reveal a ferroelectric effect in a monolayer two-dimensional mineral vermiculite. A large geometrical anisotropy factor and a large inherent electric dipole together raise the record value of Kerr coefficient by an order of magnitude, till 3.0×10-4mV-2. This finding enables an ultra-low operational electric field of 102-104Vm-1 and the fabrication of electro-optical devices with an inch-level electrode separation, which has not previously been practical. Because of its high ultraviolet stability (decay <1% under ultraviolet exposure for 1000 hours), large-scale production, and energy efficiency, prototypical displayable billboards have been fabricated for outdoor interactive scenes. This work provides new insights for both liquid crystal optics and two-dimensional ferroelectrics.

Shape-induced clusters of ellipsoids during triaxial compression: A multiscale analysis using LS-DEM

In this work, we numerically investigate the quasi-static shear behavior of ellipsoids under triaxial compression using the level set discrete element method (LS-DEM). Assemblies composed of ellipsoids with various aspect ratios are prepared at the densest states and then sheared to the critical state. Macroscopically, the stress and dilation behaviors are strongly affected by the particle shape, with the spheres having the least shear strength and dilatancy. At the particle scale, more ellipsoidal particles are more resistant to particle rotations and can effectively increase friction mobilizations.We identify the clusters in assemblies via the three-dimensional cluster labeling algorithm and then analyze the structural and mechanical properties of clusters. Based on our analysis, we find that the clusters exhibit the power-law decay in the cluster size distribution and have fractal structures. Upon shearing, the clusters tend to self-organize to gain mechanical stability, indicated by the increasing cluster stress ratio, and mainly support the deviatoric stresses in the assemblies. The mean cluster stress ratio is found to be linearly related to the macroscopic shear strength at the critical state, where more ellipsoidal shapes can gain higher cluster stress ratios, contributing to higher shear strength for the granular assembly. Microscopically, the cluster contributes more significantly to geometrical anisotropy terms while comparably to mechanical ones compared to the non-cluster.

Investigation of REV scale and anisotropy for 2D permeable fracture Networks: The role of geological entropy

To investigate the intrinsic association between geometrical properties and permeability of anisotropic fractured media, a methodology of geological entropy is applied to anisotropic fracture networks for the evaluation of seepage fields. By integrating the synthetic effect of fracture geometrical parameters (e.g., trace length, spacing, dip angle, and aperture), the global connectivity of fracture networks is quantified by the entropy scale (Hs), while the directional entropy scale (Hs,α) is used to characterize the local geometrical anisotropy in arbitrary orientations. A series of hydraulic representative elementary volumes (REVs) of fracture patterns with various geometrical properties are acquired based on continuum analysis. The permeability in the continuum scale is obtained from steady-state flow simulations. Sensitivity analyses are performed to understand the geometrical dependence of permeability parameters regarding entropy indices. It is found that a systematic increase in trace length, spacing, and dip angle is correlated with an increase, decrease, and equilibrium in entropy, respectively, which corresponds to a change in hydraulic REV sizes that can be expressed as a power-law function related to the Hs. Moreover, Hs,α can well explain the permeability anisotropy resulting from the spatial order of fracture networks, and a unified mathematical relationship for the effective permeability coefficients in arbitrary orientations versus the Hs,α is proposed, independent of variations in fracture patterns and scales. The results indicate that geological entropy, related to the geometrical properties and spatial distribution of fractures, is appropriate to characterize the permeability of anisotropic systems.

On the vertical structure of non-buoyant plastics in turbulent transport

Plastic pollution is overflowing in rivers. A limited understanding of the physics of plastic transport in rivers hinders monitoring, the prediction of plastic fate and restricts the implementation of effective mitigation strategies. This study investigates two unexplored aspects of plastic transport dynamics across the near-surface, suspended and bed load layers: (i) the complex settling behaviour of plastics and (ii) their influence on plastic transport in river-like flows. Through hundreds of settling tests and thousands of 3D reconstructed plastic transport experiments, our findings show that plastics exhibit unique settling patterns and orientations, due to their geometric anisotropy, revealing a multimodal distribution of settling velocities. In the transport experiments, particle-bed interactions enhanced mixing beyond what established turbulent transport theories (Rouse profile) could predict in low-turbulence conditions, which extends the bed load layer beyond the classic definition of the bed load layer thickness for natural sediments. We propose a new vertical structure of turbulent transport equation that considers the stochastic nature of heterogeneous negatively buoyant plastics and their singularities.

Directional Differences in Thematic Maps of Soil Chemical Attributes with Geometric Anisotropy

In the study of the spatial variability of soil chemical attributes, the process is considered anisotropic when the spatial dependence structure differs in relation to the direction. Anisotropy is a characteristic that influences the accuracy of the thematic maps that represent the spatial variability of the phenomenon. Therefore, the linear anisotropic Gaussian spatial model is important for spatial data that present anisotropy, and incorporating this as an intrinsic characteristic of the process that describes the spatial dependence structure improves the accuracy of the spatial estimation of the values of a georeferenced variable in unsampled locations. This work aimed at quantifying the directional differences existing in the thematic map of georeferenced variables when incorporating or not incorporating anisotropy into the spatial dependence structure through directional spatial autocorrelation. For simulated data and soil chemical properties (carbon, calcium and potassium), the Moran directional index was calculated, considering the predicted values at unsampled locations, and taking into account estimated isotropic and anisotropic geostatistical models. The directional spatial autocorrelation was effective in evidencing the directional difference between thematic maps elaborated with estimated isotropic and anisotropic geostatistical models. This measure evidenced the existence of an elliptical format of the subregions presented by thematic maps in the direction of anisotropy that indicated a greater spatial continuity for greater distances between pairs of points.

Multiple-polarization-sensitive photodetector Based on a plasmonic metasurface.

On-chip polarization-sensitive photodetectors are highly desired for ultra-compact optoelectronic systems. It has been demonstrated that polarization-sensitive photodetection can be realized using intrinsic chiral and anisotropy materials. However, these photodetectors can only realize the detection of either circularly polarized light (CPL) or linear polarized light (LPL) and are not applicable to multiple-polarization-sensitive photodetection. Herein, we experimentally demonstrate a metasurface-integrated semiconductor to realize multiple-polarization-sensitive photodetection at visible wavelengths. This device is composed of a MoSe2 monolayer on an H-shaped plasmonic nanostructure. The geometric chirality and anisotropy of the H-shaped nanostructure result in CPL and LPL resolved optical responses. By integrating a plasmonic metasurface with monolayer MoSe2, we converted polarization-sensitive optical absorption to the polarization-sensitive photocurrent of the device through the photoconductive effect. Polarization-sensitive photocurrent responses to both CPL and LPL are systematically investigated, which demonstrate a high photocurrent circular dichroism (CD) of 0.35 at a wavelength of 810 nm and photocurrent linear polarization (LP) of 0.4 at a wavelength of 633 nm. Our results provide a potential pathway to realize multiple-polarization-sensitive applications in medicine analysis, biology, and remote sensing.

Effects of Filler Anisometry on the Mechanical Response of a Magnetoactive Elastomer Cell: A Single-Inclusion Modeling Approach.

A finite-element model of the mechanical response of a magnetoactive elastomer (MAE) volume element is presented. Unit cells containing a single ferromagnetic inclusion with geometric and magnetic anisotropy are considered. The equilibrium state of the cell is calculated using the finite-element method and cell energy minimization. The response of the cell to three different excitation modes is studied: inclusion rotation, inclusion translation, and uniaxial cell stress. The influence of the magnetic properties of the filler particles on the equilibrium state of the MAE cell is considered. The dependence of the mechanical response of the cell on the filler concentration and inclusion anisometry is calculated and analyzed. Optimal filler shapes for maximizing the magnetic response of the MAE are discussed.

Fracture aperture anisotropic effects on field scale enhanced geothermal system thermal performance

The thermal performance of a field-scale Enhanced Geothermal System was investigated, considering anisotropy in fracture aperture distributions. The fracture aperture distribution was treated as an autocorrelated random field with different ranges in the x- and y-directions, defined by geometric anisotropic ratios between 1.5 and 4. To model realistic aperture distributions, constraints were applied to ensure the aperture distributions had Hurst exponents that are typical of fractures observed in nature.The thermal drawdown between the perpendicular and parallel flow configurations was compared, revealing a 60 % likelihood of improved heat transfer in the perpendicular flow configuration. When exploring the impact of geometric anisotropy ratios on thermal performance, aperture distributions with a geometric anisotropy ratio of 2 demonstrated about 70 % better thermal performance in favor of the perpendicular flow direction. This ratio also exhibited aperture distributions with Hurst exponents within the range found in natural faults and fractures, suggesting a 70 % likelihood of improved thermal performance in the perpendicular flow configuration for actual fracture behavior.The perpendicular flow configuration mainly exhibited tortuous flow paths, while the parallel flow direction mostly had near-horizontal flow paths. The tortuous flow paths increased contact between the fluid and fracture surface area, resulting in improved thermal performance.The findings suggest the importance of considering shear direction at the field scale when placing wells. Placing a well perpendicular to the direction of slip or shear may yield enhanced thermal performance compared to placing a well parallel to the direction of slip or shear.

On the magnetic bistability of small iron clusters used in scanning tunneling microscopy tip preparation

The combination of electron spin resonance with scanning tunneling microscopy has resulted in a unique surface probe with sub-nm spatial and neV energy resolution. The preparation of a stable magnetic microtip is of central importance, yet, at the same time remains one of the hardest tasks. In this work, we rationalize why creating such microtips by picking up a few iron atoms often results in magnetically stable probes with two distinct magnetic states. By using density functional theory, we show that randomly formed clusters of five iron atoms can exhibit this behavior with magnetic anisotropy barriers of up to 73 meV. We explore the dependence of the magnetic behavior of such clusters on the geometrical arrangement and find a strong correlation between magnetic and geometric anisotropy—the less regular the cluster the higher its magnetic anisotropy barrier. Finally, our work rationalizes the experimental strategy of obtaining stable magnetic microtips.

Variabilidade espacial de índices multiespectrais biofísicos baseados na heterogeneidade e anisotropia para monitoramento de precisão

ABSTRACT The study aimed to characterize the spatial structure of variability of biophysical indexes of vegetation through images obtained by Unmanned Aerial Vehicles under strong heterogeneity and anisotropy, using geostatistical procedures. Plots with different types and densities of culture were evaluated in a didactic vegetable garden. Five vegetation indexes obtained from aerial multispectral camera images were evaluated parallel with geostatistical analysis and anisotropy investigation for multiscale spatial modeling. For the studied domain, geometric anisotropy was identified for the biometric indexes. The spherical model presented a better fit when anisotropy was not considered, whereas the exponential model had the best performance in the anisotropic analysis. Contrasting targets were better identified in multispectral images and considering anisotropy. The Soil-Adjusted Vegetation Index is recommended for similar applications.

Improved polygonal constitutive model for columnar jointed basalt and its application in tunnel stability analysis

The columnar jointed basalt (CJB) in the dam site of the Baihetan hydropower station exhibits noticeable geometric anisotropy. The current constitutive relationship based on a quadrangular columnar structure fails to truly represent the natural characteristics of the CJB. To address the stability problem of the diversion tunnel at the dam foundation, the mechanics of composite materials and Goodman superposition principle were employed to establish improved three-dimensional constitutive relations for pentagonal and hexagonal CJBs. The constitutive relations of three types, including the quadrangular prism CJB, were optimized by considering the impact of transverse joints and internal staggered zones. The mechanical parameters of the Baihetan CJB were appropriately evaluated using the three constitutive relations, and the achieved results demonstrated that the determined elastic moduli of the three improved constitutive models were consistent with field results. Subsequently, the three anisotropic constitutive models were employed for numerical simulations of the diversion tunnel excavation in the Baihetan CJB stratum. Strain field tests were conducted at different locations within the tunnel, and an empirical method was proposed that combined statistical data on the shape of CJBs at the site, which can effectively predict the deformation of the surrounding rock. The theoretical and numerical results provide crucial reference values for engineering optimization design.

Thermophysical properties of pressure-sensitive paint

The paper deals with the problem of the thermophysical properties of pressure-sensitive paint (PSP). The paint was used to determine the pressure distribution on the surface of models examined in wind tunnel aerodynamic tests. The aim of the study was to provide reliable data on the values of thermophysical parameters and their dependence on temperature. PSP is a thin-film structure that is applied layer by layer a specific number of times on a metallic substrate, and determining the thermal properties requires non-standard test procedures to obtain reliable results. The measurements were carried out on paint fragments separated from the flat substrate of a metallic thin film (molybdenum), from which samples were obtained for complementary studies of the thermophysical properties. The study includes weight measurements, thermogravimetric analysis, micro-calorimetric analysis, and measurement of effective thermal diffusivity using the temperature oscillation technique. The findings are complemented with structural test data collected by means of scanning electron microscopy, surface characterisation, and density determination by the displacement method. The analysis of the structural test data indicates the micro-structural isotropy of the examined material with geometric anisotropy of the layer as a whole. In this way, the results of thermal diffusivity tests can be properly evaluated, and reliable data can be obtained on the complete thermophysical properties of the PSP layer. The indirectly determined thermal conductivity, i.e., by recalculating the specific heat, density, and thermal diffusivity data, allows the test material to be classified as an insulator. Apart from the presentation of the test results and calculations, this paper also contains a brief discussion of the test procedures.