Minimum Conductivity Research Articles

Drought decreases water storage capacity of two arboreal epiphytes with differing ecohydrological traits

Arboreal epiphytes, plants that grow on trees, can significantly increase rainwater storage and evaporation (i.e., “interception”) within canopies. Drought conditions may affect this hydrological role, as epiphytes' physiological responses change leaf properties that affect water retention. Drought-induced changes in epiphyte water storage capacity could substantially alter canopy hydrology, but have not been studied. We tested the effects of drought on the water storage capacity (Smax) of leaves and leaf properties of two epiphytes with distinct ecohydrological traits: resurrection fern (Pleopeltis polypodioides), and Spanish moss (Tillandsia usneoides). Both species are common in maritime forests of the Southeastern USA, where climate change is expected to decrease precipitation in spring and summer. To simulate drought, we dried leaves to 75 %, 50 %, and ~25 % of fresh weight, and quantified their Smax in fog chambers. We measured relevant leaf properties: hydrophobicity, minimum leaf conductance (gmin; a measure of water loss under drought), and Normalized Difference Vegetative Index (NDVI). We found that drought significantly reduced Smax and increased leaf hydrophobicity for both species, indicating that lower Smax may be due to shedding of droplets. While the overall reduction in Smax did not differ between the two species, they exhibited distinct drought responses. Dehydrated T. usneoides leaves had lower gmin, demonstrating the ability to limit water loss under drought. P. polypodioides increased gmin when dehydrated, consistent with its extraordinary ability to withstand water loss. NDVI decreased with dehydration in T. usneoides but not P. polypodioides. Our results suggest that increased drought may have a dramatic effect on canopy water cycling by reducing the Smax of epiphytes. Reduced rainfall interception and storage in forest canopies could have widespread effects on hydrological cycling, thus understanding the potential feedbacks of plant drought response on hydrology is crucial. This study highlights the importance of connecting foliar-scale plant response with broader hydrological processes.

Hydraulic differences between flowers and leaves are driven primarily by pressure-volume traits and water loss.

Flowers are critical for successful reproduction and have been a major axis of diversification among angiosperms. As the frequency and severity of droughts are increasing globally, maintaining water balance of flowers is crucial for food security and other ecosystem services that rely on flowering. Yet remarkably little is known about the hydraulic strategies of flowers. We characterized hydraulic strategies of leaves and flowers of ten species by combining anatomical observations using light and scanning electron microscopy with measurements of hydraulic physiology (minimum diffusive conductance (g min) and pressure-volume (PV) curves parameters). We predicted that flowers would exhibit higher g min and higher hydraulic capacitance than leaves, which would be associated with differences in intervessel pit traits because of their different hydraulic strategies. We found that, compared to leaves, flowers exhibited: 1) higher g min, which was associated with higher hydraulic capacitance (C T); 2) lower variation in intervessel pit traits and differences in pit membrane area and pit aperture shape; and 3) independent coordination between intervessel pit traits and other anatomical and physiological traits; 4) independent evolution of most traits in flowers and leaves, resulting in 5) large differences in the regions of multivariate trait space occupied by flowers and leaves. Furthermore, across organs intervessel pit trait variation was orthogonal to variation in other anatomical and physiological traits, suggesting that pit traits represent an independent axis of variation that have as yet been unquantified in flowers. These results suggest that flowers, employ a drought-avoidant strategy of maintaining high capacitance that compensates for their higher g min to prevent excessive declines in water potentials. This drought-avoidant strategy may have relaxed selection on intervessel pit traits and allowed them to vary independently from other anatomical and physiological traits. Furthermore, the independent evolution of floral and foliar anatomical and physiological traits highlights their modular development despite being borne from the same apical meristem.

Continuous Metal-Insulator Transition and Scale Laws in Metallic n-Type InP

We have studied the transport properties in metallic n-type InP semiconductor. We show that the dependence on temperature of metallic electrical conductivity obey to the law 𝜎 = 𝜎(𝑇 = 0) + 𝑚𝑇1/2. We highlight the absence of a minimum electrical conductivity 𝜎𝑚𝑖𝑛 proposed by Mott at the metal-insulator transition. We show that the conductivity at temperature T = 0 K, 𝜎(𝑇 = 0) , follows a scaling law as a function of the effective parallel and perpendicular Bohr radii 𝑎∥ and 𝑎⊥.

Cold temperature and aridity shape the evolution of drought tolerance traits in Tasmanian species of Eucalyptus.

Perennial plant species from water-limiting environments (including climates of extreme drought, heat, and freezing temperatures) have evolved traits that allow them to tolerate these conditions. As such, traits that are associated with water stress may show evidence of adaptation to climate when compared among closely related species inhabiting contrasting climatic conditions. In this study, we tested whether key hydraulic traits linked to drought stress, including the vulnerability of leaves to embolism (P50 leaf) and the minimum diffusive conductance of shoots (gmin) were associated with climatic characteristics of fourteen Tasmanian eucalypt species from sites that vary in precipitation and temperature. Across species, greater cavitation resistance (more negative P50 leaf) was associated with increasing aridity and decreasing minimum temperature. In contrast, gmin showed strong associations with aridity only. Among these Tasmanian eucalypts, evidence suggests that trait variation is influenced by both cold and dry conditions, highlighting the need to consider both aspects when exploring adaptive trait-climate relationships.

Winner-Takes-All Neural Network Based on 3D NAND Flash With 1-Bit Erase Scheme

3D NAND flash memory constitutes strong competitors for neuromorphic computing due to its high density and mature technology. Neural networks based on 3D NAND flash differential pair have been reported since conventional block erase scheme hinders individual conductance modulation. However, the differential pair scheme halves the efficient synaptic density and erase operation is still inevitable when one of the pair devices reaches its minimum conductance. To overcome these shortcomings, the 1-bit erase scheme was proposed based on gate induced drain leakage (GIDL) effect. But in this scheme, there are risks in unintended erase. In this work, gradient bias is adopted to eliminate the potential risks in the 1-bit erase scheme. Both TCAD simulation and experimental results manifest better inhibition of unintended erase. Based on this improved scheme, a winner-takes-all neural network is constructed, where the efficient synaptic density is doubled and free from the minimum conductance dilemma in previous work based on differential pair scheme.

Small signal and noise analysis of T-gate HEMT with polarization doped buffer for LNAs

Small signal behavior and RF noise performance of T-gate InAlN/GaN HEMT with polarization doped buffer (PDB-HEMT) have been examined in this paper and compared to conventional HEMTs at GHz frequency range. Enhancement mode operation is possible in the PDB-HEMT device, which has a recessed T-gate structure with a gate length of 10 nm and delivers the threshold voltage (Vth) of 0.9 V and a high transconductance of 1.55 S/mm. This study examines the auto/cross-correlation factor, minimum noise figure, reflection/transmission coefficients, noise conductance, and optimal noise resistance and reactance. The enhanced transconductance of PDB-HEMT has resulted in a considerable increase in the forward transmission coefficient and a decrease in the input/output reflection coefficient compared to traditional HEMTs. It has also been shown that the PDB- HEMT has a lower noise figure and noise conductance than the GaN buffer HEMT by 57% and 20%, respectively. This research demonstrates that the T-gate polarization doped buffer (PDB-HEMT) structure is an excellent choice for Low Noise Amplifiers (LNA) operating at higher frequencies.

First-principles calculations to investigate mechanical, thermoelectric and optical performance of inorganic double perovskites Rb2AgAlZ6 (Z = Br, I) for energy harvesting

The clean and green energy is a merging technology of advanced era to achieve the demands of energy requirements. For this purpose, the double perovskites Rb2AgAlZ6 (Z = Br, I) are explored comprehensively in terms of optical, mechanical, thermoelectric, and thermodynamic characteristics. The stability of structures, elastic and thermodynamic have been ensured through tolerance factor, Born Criteria, and formation energy. The elastic constants of cubic symmetry are analyzed to distinguish ductile/brittle nature, anisotropy, Harness, minimum lattice thermal, conductivity, melting and Debye temperatures. The anions (Br, I) modified the band gaps (2.60, 1.08) eV which turned the absorption of light energy from ultraviolet to visible portion of spectrum. The absorption band of Rb2AgAsI6 in the energy range 1.7eV–3.4 eV is particularly significant for solar cells. The large Seebeck coefficient, and electrical conductivity while particularly low lattice thermal conductivity has been increased the figure of merit. The large figure of at low temperature open the new finding roots for realization of these DPs for thermoelectric and other energy applications.

Magic angle in thermal conductivity of twisted bilayer graphene

We report a local minimum in thermal conductivity in twisted bilayer graphene (TBG) at the angle of 1.08°, which corresponds to the ‘magic angle’ in the transition of several other reported properties. Within the supercell of a moiré lattice, different stacking modes generate phonon scattering sites which reduce the thermal conductivity of TBG. The thermal magic angle arises from the competition between the delocalization of atomic vibrational amplitudes and stresses on one hand, and the increased AA stacking density on the other hand. The former effect weakens the scattering strength of a single scatterer while the latter one increases the density of scatterers. The combination of these two effects eventually leads to the apparition of the highlighted irregularity in heat conduction. The manifestation of a magic angle, disclosing new thermal mechanisms at nanoscale, further uncovers the unique physics of two-dimensional materials.

Thermal and electrical properties of nanocrystalline superionic NaxCu1.75S (x=0.1, 0.15, 0.2, 25) compounds

The paper presents the results of the studies of thermal properties of nanocrystalline superionic Na x Cu 1.75 S (x = 0.1, 0.15, 0.2, 25) compositions, and preliminary results of Na 0.1 Cu 1.75 S using as energy stored cathode material in Na-ion half-cell with NaPF 6 electrolyte and Na anode. The compositions contain a few copper sulfide phases: monoclinic chalcocite Cu 2 S, orthorhombic anilite Cu 1.75 S, triclinic roxbyite Cu 1.74÷1.82 S, also the compositions can contain monoclinic Na 2 Cu 4 S 3 , orthorhombic Na 2 S, cubic Cu 2 O as inclusion phases. The sizes of powder particles lie in the range from 10 to 113 nm. Differential scanning calorimetry revealed in Na 0.1 Cu 1.75 S the endothermic thermal effects with critical temperatures near 123 o C, 422 o C and 442 o C, caused by structural transitions in copper sulfide. Fourth endothermic peak at 323 o C presumably belongs to Na 2 S phase. The minimum for the Fermi level at about 420°C is found with using of the e.m.f. E of the electrochemical cell of the Cu/CuBr/Na 0.10 Cu 1.75 S/Pt, which corresponds to minimum for the carrier concentration. This conclusion correlates well with the observed conductivity minimum at about 410°C. Electrode material Na 0.10 Cu 1.75 S achieved a significant specific energy density 146.5 mAh/g in half-cell assembled from the cathode active material, electrolyte (NaPF 6 in 0.5 mol PC) and Na anode.

Bandgap energy prediction of senary zincblende III–V semiconductor compounds using machine learning

Two complimentary machine learning (ML) models are developed to estimate the bandgap energy (Eg) of senary zincblende (ZB) III–V semiconductor compounds Alx1Gax2Inx3Py1Asy2Sby3 from molar fractions. The models work – as well – for any compound with smaller number of constituent elements from binaries to quinaries. Some of these compounds exhibit transition between a direct and an indirect Eg as a function of composition. This is due to the fact that the bandgap for this class of materials is either the direct gap at Γ point (EgΓ) or the indirect one between the maximum valance band at Γ point and the minimum conduction band around X point (EgX). Hence, to capture precisely the Eg and its state, the ML models estimate separately the EgΓ and EgX where the lowest energy gap is the effective Eg. For model training, 18 ternary ZB III–V semiconductor compounds are used, which contain all possible ternary configurations of III-type cations (Al, Ga, In) and V-type anions (P, As, Sb). The achieved testing accuracy using cubic regression with ridge regularization – in terms of root mean square error (RMSE) – are 7.583 and 0.021 meV for EgΓ and EgX, respectively. These correspond to R2 of 0.99995 and 1.00000 (8 nines), respectively. To validate the models, they are benchmarked against experimental measurements of four different quaternary ZB III–V semiconductor compounds. The agreement is very noticeable demonstrating the validity and the excellent accuracy of the developed models.

Water permeability of different aerial tissues of carnations is related to cuticular wax composition.

Cuticular wax protects aerial plant tissues against uncontrolled water loss. To compare the differences among tissues, cultivars, and postharvest stages, we characterized the surface morphology, water permeability, and chemical composition of cuticular wax on the leaf, calyx, and petals of two carnation cultivars ('Master' and 'Lady green') at two postharvest stages. Obvious differences in these characteristics were found among tissues but not among cultivars or postharvest stages. The leaf surface was relatively smooth, whereas convex cells were observed on the petals. The mean minimum conductance of leaves was significantly higher than that of the calyx, followed by that of petals. It ranged between 8.8 × 10-4 m s-1 for 'Lady green' leaves at Stage II and 3.6 × 10-5 m s-1 for 'Master' petals at Stage I. Petal wax contained high concentrations of n-alkanes, whereas primary alcohols dominated in leaf wax. The weighted average chain length (ACL) was higher in petal wax than in leaf wax; it ranged from 19.6 in 'Lady green' leaves to 24.14 in 'Lady green' petals at Stage I. In conclusion, carnation petals are characterized by numerous convex cells on both the adaxial and abaxial surfaces, and their main cuticular wax components, alkanes, have a higher ACL than leaf cuticular wax, which contributes to their higher water barrier property. The results provide further evidence for the association between cuticular chemical composition and the physiological function of the cuticle in blocking water transpiration.

Strain-Modulated Perfect Valley Precession and Valley Transistor in Graphene

We propose the realization of perfect valley precession by use of strain, which gives rise to an effective vector potential and moves two valleys in opposite directions in momentum space. It is shown that the spatial precession period is independent of both the Fermi energy and the transverse wave vector. This is crucial to perfect precession in a practical device with multiple transverse wave vectors or modes. To theoretically demonstrate the perfect valley precession, we investigate the conductivity of a Kekul\'e graphene superlattice/graphene/Kekul\'e graphene superlattice junction that acts as a valley transistor. Due to the valley precession, the conductivity exhibits perfect oscillations with the strain and the conductivity minima are very close to zero. Our finding provides a strategy to design ideal valleytronics and straintronics devices.

Influence of heterogeneous thermal conductivity on the long-term evolution of the lower-mantle thermochemical structure: implications for primordial reservoirs

Abstract. The long-term evolution of the mantle is simulated using 2D spherical annulus geometry to examine the effect of heterogeneous thermal conductivity on the stability of reservoirs of primordial material. Often in numerical models, purely depth-dependent profiles emulate mantle conductivity (taking on values between 3 and 9 Wm-1K-1). This approach synthesizes the mean conductivities of mantle materials at their respective conditions in situ. However, because conductivity also depends on temperature and composition, the effects of these dependencies on mantle conductivity are masked. This issue is significant because dynamically evolving temperature and composition introduce lateral variations in conductivity, especially in the deep mantle. Minimum and maximum variations in conductivity are due to the temperatures of plumes and slabs, respectively, and depth dependence directly controls the amplitude of conductivity (and its variations) across the mantle depth. Our simulations allow assessing the consequences of these variations on mantle dynamics, in combination with the reduction in thermochemical pile conductivity due to its expected high temperatures and enrichment in iron, which has so far not been well examined. The mean conductivity ratio from bottom to top indicates the relative competition between the decreasing effect with increasing temperature and the increasing effect with increasing depth. We find that, when depth dependence is stronger than temperature dependence, a mean conductivity ratio >2 will result in long-lived primordial reservoirs. Specifically, for the mean conductivity profile to be comparable to the conductivity often assumed in numerical models, the depth-dependent ratio must be at least 9. When conductivity is underestimated, the imparted thermal buoyancy (from heat-producing element enrichment) destabilizes the reservoirs and influences core–mantle boundary coverage configuration and the onset of dense material entrainment. The composition dependence of conductivity only plays a minor role that behaves similarly to a small conductivity reduction due to temperature. Nevertheless, this effect may be amplified when depth dependence is increased. For the cases we examine, when the lowermost mantle's mean conductivity is greater than twice the surface conductivity, reservoirs can remain stable for very long periods of time, comparable to the age of the Earth.

Nocturnal Transpiration May Be Associated with Foliar Nutrient Uptake.

Aerosols can contribute to plant nutrition via foliar uptake. The conditions for this are best at night because the humidity is high and hygroscopic, saline deposits can deliquesce as a result. Still, stomata tend to be closed at night to avoid unproductive water loss. However, if needed, nutrients are on the leaf surface, and plants could benefit from nocturnal stomatal opening because it further increases humidity in the leaf boundary layer and allows for stomatal nutrient uptake. We tested this hypothesis on P-deficient soil by comparing the influence of ambient aerosols and additional foliar P application on nocturnal transpiration. We measured various related leaf parameters, such as the foliar water loss, minimum leaf conductance (gmin), turgor loss point, carbon isotope ratio, contact angle, specific leaf area (SLA), tissue element concentration, and stomatal and cuticular characteristics. For untreated leaves grown in filtered, aerosol-free air (FA), nocturnal transpiration consistently decreased overnight, which was not observed for leaves grown in unfiltered ambient air (AA). Foliar application of a soluble P salt increased nocturnal transpiration for AA and FA leaves. Crusts on stomatal rims were shown by scanning electron microscopy, supporting the idea of stomatal uptake of deliquescent salts. Turgor loss point and leaf moisture content indicated a higher accumulation of solutes, due to foliar uptake by AA plants than FA plants. The hypothesis that deliquescent leaf surface salts may play a role in triggering nocturnal transpiration was supported by the results. Still, further experiments are required to characterize this phenomenon better.

Effect of Aggregate Size and Compaction on the Strength and Hydraulic Properties of Pervious Concrete

Pervious concrete is one of the emerging sustainable materials that has recently gained the attention of many researchers. The importance of pervious concrete mainly depends on its application and on a modern integrated approach in which it is employed to reduce the effects of flooding. The main goal of this experimental analysis is to study the significance of aggregate size and the degree of compaction on the mechanical and hydraulic properties of pervious concrete. Eleven concrete mixture proportions were investigated by controlling the constituents with different aggregate fractions. The important variables considered were the aggregate sizes, viz., 0/4 mm, 4/8 mm, and 8/16 mm, with four different degrees of compaction. The porosity of the concrete structure was obtained by the partial filling of the voids in the aggregates with cement paste. The ingredients of the pervious concrete were also varied to study their significance and to evaluate the predominant factor that controls the mechanical and hydraulic properties based on the test results. Tests were conducted to determine properties such as compacting factor, compressive strength, splitting tensile strength, abrasion resistance, porosity, and hydraulic conductivity. The study revealed that the degree of compaction was one of the critical factors governing the strength and hydraulic properties of the pervious concrete; the maximum strength and minimum hydraulic conductivity were achieved with a higher degree of compaction. The test results imply that the cement content is the predominant factor determining the fresh and tensile properties of the pervious concrete, rather than the size of the aggregates used. In addition, the results also illustrated that the highly compacted pervious concrete samples made with 4/8 mm aggregates exhibited improved abrasion resistance and strength properties, but slightly reduced hydraulic conductivity, despite the designed porosity.

First-principles study on GeC/β-AsP heterostructure with type-II band alignment for photocatalytic water splitting

Based on first-principles calculations, the stacking, electronic and optical properties of GeC/β-AsP heterostructure have been explored. It is found that the GeC/β-AsP heterostructure has a direct band gap of 1.28 eV with a type-II band arrangement. Moreover, it is found that the charge density states with the maximum valence band and the minimum conduction band are located in different layers. Thus, the electron-hole pair is spatially separated, which is helpful for improving the photocatalytic performance. In ultraviolet and visible light regions, high optical absorption in an order of 106 cm−1 is found in GeC/β-AsP heterostructure, which is higher than that in its corresponding component monolayers. Considering the potential application of hydrogen reduction and oxygen oxidation, it is found that GeC/β-AsP heterostructure can be used for photocatalytic water cracking.

A physics rule to design aperiodic width-modulated waveguides for minimum phonon transmission with Bayesian optimization.

Aperiodic nano-waveguides (nWVGs) and superlattices (SLs) limit phonon transmission and heat conduction much more efficiently than periodic ones. They could block parasitic heat conduction that restricts heat management and energy conversion at the nanoscale. Aperiodicity can be realized in multiple ways and with variable degrees of complexity. Machine learning optimization of hetero-SLs for minimum coherent phonon conduction showed optimal aperiodicity for moderate disorder against physics intuition. Here, we report on optimal aperiodicity in width-modulated nWVGS for maximum disorder as expected by physics. Optimizing aperiodic geometry modulation is particularly challenging due to the enormous possible configurations. We set up a feasible optimization problem removing unnecessary complexity and we demonstrate efficient Bayesian optimization. Our results confirm the predicted physics rule that minimum thermal conductance occurs for the most disordered arrays of modulation units; the degree of disorder being quantified by the number of non-identical modulation units. Our work opens a route to design geometrical aperiodicity and control transmission across metamaterials.

Study of Physico-Chemical Properties of Phosphorate Solutions

The results of studies of the physicochemical properties of extraction phosphoric acids containing magnesium in the presence of ammonium nitrate are presented. A decrease in the heat of vaporization in the H3PO4-H2O system was found in the range of acid concentrations of 20-30% and 37-45% P2O5. At an acid concentration of 20, 35% and 45% P2O5 there is a minimum electrical conductivity, while at a concentration of 30 and 40% P2O5, the electrical conductivity of solutions reaches a maximum value at temperatures of 25-45%, which is explained by structural changes occurring in the acid during dissociation and dimerization, depending on the concentration. The electrical conductivity of the H3PO4-H2O system decreases with the introduction of magnesium sulfate and ammonium nitrate. The regularity of the thickening of magnesium-containing acid is substantiated.

First-principles assessments of the electronic, and magneto-optical characteristics of Fe–Mn co-doped anatase TiO2 for photo-catalysis applications

First principles modeling is conducted to scrutinize the structural, chemical, electronic structures, bonding character, and magneto-optical features of intrinsic or pure anatase TiO2, Fe or Mn single-atom doped, and Mn–Fe diatom co-doped anatase TiO2 systems, respectively. Herein, the spin-polarized density functional theory (DFT) concerted with the on-site Hubbard (U) correction scheme for the Coulomb interaction, is utilized for the exchange-correlation term, as the generalized gradient approximation (GGA)+U. The spin-polarized density of states of Mn mono-atom doped anatase TiO2 material indicated a magnetic semiconductor attribute for both down/up spin components. Conversely, the outcome spin-polarized density of states of both Fe-doped and Mn–Fe co-doped anatase TiO2 materials illustrated the emergence of an intermediate band behavior. Accordingly, three magnetic impurity bands are produced in Mn–Fe co-doped anatase TiO2, the first two spin-up bands are located just uppermost the valence states nearby the Fermi level and the third spin-up/down band is lying far from the Fermi level just below the minimum conduction band. Interestingly, the spin-polarized charge density displayed an orbital ordering between the O 2p-orbitals and 3d-orbitals of Mn–Fe doped diatoms in the host TiO2 anatase system. The valuable optical ingredients, such as the optical absorption coefficient, refractive index, reflectivity spectra, optical conductivity, and electron energy loss function, are inspected and discussed. Moreover, the optical absorption coefficient characteristics of the mono-doped Mn/Fe and Mn–Fe co-doped TiO2 anatase structure displayed a relocation in the absorption feature edges towards the visible electromagnetic radiation regime. This means that the induced impurity bands delineate the essential contributor for boosting the catalytic activity in the visible light. It is expected that the Fe–Mn co-doped anatase TiO2 system could be a compelling candidate for its ultimate use in the photo-catalysts or magnetic storage devices.

Mathematical Models for Machining Optimization of Ampcoloy 35 with Different Thicknesses Using WEDM to Improve the Surface Properties of Mold Parts.

Wire electrical discharge machining (WEDM) is an unconventional machining technology that can be used to machine materials with minimum electrical conductivity. The technology is often employed in the automotive industry, as it makes it possible to produce mold parts of complex shapes. Copper alloys are commonly used as electrodes for their high thermal conductivity. The subject of this study was creating mathematical models for the machining optimization of Ampcoloy 35 with different thicknesses (ranging from 5 to 160 mm with a step of 5 mm) using WEDM to improve the surface properties of the mold parts. The Box-Behnken type experiment was used with a total of 448 samples produced. The following machining parameters were altered over the course of the experiment: the pulse on and off time, discharge current, and material thickness. The cutting speed was measured, and the topography of the machined surfaces in the center and at the margins of the samples was analyzed. The morphology and subsurface layer were also studied. What makes this study unique is the large number of the tested thicknesses, ranging from 5 to 160 mm with a step of 5 mm. The contribution of this study to the automotive industry and plastic injection mold production is, therefore, significant. The regression models for the cutting speed and surface topography allow for efficient defect-free machining of Ampcoloy 35 of 5-160 mm thicknesses, both on the surface and in the subsurface layer.