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A nano-multilayered ZrN/TiAlN was deposited as the interlayer to enhance the coating hardness and wear resistance between the inner TiAlN and outer ZrN layers. The structural evolution and mechanical performance of the multilayer coatings were significantly achieved. High-resolution transmission electron microscopy (HRTEM) revealed a local epitaxial growth between the nano multilayers, in which (111) crystal planes for TiAlN was parallel to (111) crystal planes for ZrN. Nanoindentation experiments were conducted to evaluate the mechanical properties. TiAlN-ZrN/TiAlN-ZrN and ZrN-TiAlN-ZrN/TiAlN-ZrN featuring a multilayered architecture, exhibited the higher hardness values of 24.68 ± 3.27 GPa and 25.34 ± 3.42 GPa respectively. Additionally, The wear mechanism for coatings under a load of 10N was dominated by abrasive wear, whereas that under a load of 15N was mainly oxidation wear and abrasive wear. Furthermore, in comparison to TiAlN-ZrN, the wear tracks on TiAlN-ZrN/TiAlN-ZrN exhibited a lower width value about 423 μm, indicating a better wear resistance. This enhancement could attribute to the alternating stress fields hindering the dislocation movement, which arose from coherency strains due to a mismatch in the lattice differences between nano multilayers. Simultaneously, the interface of nano layers inhibited oxygen diffusion, enhanced the antioxidant effects and further improved the wear behavior. [ABSTRACT FROM AUTHOR]

The deviation of the power-weighted center of the echo signal from the geometric center within the velocity estimation window for calculating strain rate (SR) causes an estimation error. This study aimed to confirm whether an erroneous multilayer pattern in the SR distribution of the left ventricular wall could be corrected by considering the power-weighted center of the echo signal. The SR distributions were measured locally in the transmural direction around the pre-ejection and early diastolic phases in healthy volunteers. The estimation error related to the power-weighted center of the echo signal was corrected using a previously proposed method, and the effectiveness of the correction was confirmed based on the accuracy of the estimated myocardial displacement. The SR distribution in early diastole was observed as multilayers of low- and high-amplitude negative SRs. However, this multilayer pattern disappeared after correction. In the pre-ejection phase, multilayers of positive and negative SRs were observed in the SR distributions with and without correction. This correction was sufficiently effective in accurately tracking the local peak of the echo signal. The multilayer pattern of low- and high-amplitude positive or negative SRs is caused by estimation errors related to the power-weighted center of the echo signal. The multilayer pattern of positive and negative SRs might not be caused by these errors and might relate to the actual change in myocardial thickness because the estimation errors do not convert the negative (positive) SR to positive (negative) in a homogeneous negative (positive) SR distribution. [ABSTRACT FROM AUTHOR]

Improving piezoelectric power-generation capability has been explored by modulating materials chemistry and device structure for specific low-power applications. Herein, high-performance multilayer cantilever structures based on perovskite 0.4Pb(Zn 1/3 Nb 2/3)O 3 –0.6Pb(Zr 0.5 Ti 0.5)O 3 (0.4PZN–0.6PZT) with CuO additives are proposed as an example of electromechanical energy harvester utilizing nonresonant-frequency mechanical source. Even with low-temperature co-firing at 900 °C for 2 h to use inexpensive Ag inner electrodes, an optimized unimorph single-layer cantilever exhibited the best normalized power density of ∼10.8 mW cm−2 g−2 Hz−1 at 2 Hz with an acceleration of 0.028 g, which is far better than typical values reported for cantilever harvesters. The power value itself increased from ∼142.7 to ∼508.5 μW with four layers while maintaining the high power density. The enhanced power with multilayers was attributed to the increased current due to extensive surface-charge polarization as the effective electrode coverage area was approximately quadrupled. [ABSTRACT FROM AUTHOR]

Solar-driven hydrogen production via water splitting is regarded as the most practical and efficient method of production of green energy. Hydrogen is a suitable renewable energy, which is important for environmental sustainability, renewable energy is considered to be the most environmentally friendly, and cost-effective. However, the efficiency of producing hydrogen via photocatalysis remains low. The efficiency of hydrogen production through photocatalysis can be enhanced by preparing a suitable and efficient photocatalyst. For this purpose, the band gap of metal oxides needs to align to reduce it for the photocatalytic process. To improve the efficiency of hydrogen production the band gap of metal oxides (CdTe, WO 3 , CuO, SnO 2 , and MoO 3) is aligned to reduce it, for the photocatalytic process in terms of multilayer heterostructure thin films. In this particular study, a physical vapor deposition technique is used to deposit metal oxides (CdTe, WO 3 , CuO, SnO 2 , and MoO 3) on the ITO substrate. The photo-electrochemical properties of multilayers showed quite better results as compared to individual thin films. The multilayer heterostructure thin film of metal oxides (CdTe, WO 3 , CuO, SnO 2 , and MoO 3) is carried out through XRD, FTIR, UV, transmittance, SEM, and LSV under dark conditions and light conditions. UV of thin film heterostructure reveals the absorbance of solar spectra and the Tauc plot via UV spectroscopy confirmed the reduction of the band gap of metal oxides. SEM study confirmed the grain size of the thin film and the surface plot of the films for the absorption of solar spectra for the generation of hydrogen. LSV showed better photocurrent response under light conditions as compared to dark conditions. The EIS analysis confirmed the charge transfer at the electrode-electrolyte interface for multilayer heterostructure is much better than that of individual metal oxide thin film. The decrease of the EIS curve confirmed the enhancement of photocurrent. The hydrogen production rate per hour was also measured. • Multilayer heterostructure thin films were prepared by the physical vapor deposition method. • Multilayers heterostructure has less charge transfer resistance compared to other metal oxides thin film. • EIS study of multilayer heterostructure showed low impedance which gives a better photocurrent response compared to its constituents. • The Solar light to hydrogen conversion (STH%) efficiency was found to be 3.96%. • Multilayer heterostructure thin films have a photocatalytic hydrogen generation rate of 29350.59 mol g−1 h−1 was measured. [ABSTRACT FROM AUTHOR]

Zinc sulfide hybrids with different stacked ZnS multilayers were prepared using a chemical precipitation method in a solvent mixture of Ethylenediamine:Water:Butanol via two routes - nitrate and acetate salt precursors. The impact of butanol solvent contents (30 and 60 vol%) on the formation of orthorhombic-ZnS(en) 0.5 hybrid with different stacking of ZnS layers was comprehensively analyzed using X-ray diffraction, Fourier Transform Infrared, X-ray photoelectron spectroscopy, and diffuse reflectance spectroscopy. Scanning electron microscopy was employed to study the influence of the mixture solvent on particle size and morphology of the resulting ZnS(en) 0.5 hybrid micro flakes or nanosheets. The photocatalytic response was evaluated through hydrogen production reactions using low photocatalyst load under UV light irradiation, conducted over four reaction cycles. A significant increase in hydrogen production rate (4.6 and 4.0 times more active) was achieved for the exfoliated ultrathin nanosheet ZnS(en) 0.5 hybrid prepared with lower butanol contents from the nitrate and acetate route, respectively. This enhancement was attributed to the reduced size of the nanosheets of stacked ZnS multilayers, which resulted from the incorporation of 30 vol% of butanol during the synthesis. Overall, the findings indicate that the Ethylenediamine:Butanol solvent system plays a crucial role in tuning the degree of ZnS stacking layers, the particle size, and morphology of ZnS(en) 0.5 hybrids, leading to improved photocatalytic performance in hydrogen production reactions. [Display omitted] • Ultrathin ZnS(en) 0.5 nanosheets were prepared by chemical precipitation method. • ZnS(en) 0.5 nanosheets were obtained in ethylenediamine with 30 vol% of butanol. • Nanosheets of low degree of stacking ZnS layers was obtained using acetate route. • High H 2 production rate was achieved with ultrathin ZnS(en) 0.5 nanosheets. [ABSTRACT FROM AUTHOR]

[Display omitted] Recent efforts in growing two-dimensional (2D) multilayers have enabled the synthesis of single crystalline 2D multilayers in a wafer scale through the seamless stitching of multiple epitaxial 2D islands. Unlike previously observed wedding-cake or inverted-wedding-cake structures, these multilayer islands have the same size and shape in each layer with aligned edges. In this study, we investigated the underlying growth mechanisms of synchronic 2D multilayers growth and have showed that a heterogenous layer on a crystalline substrate is critical for maintaining the synchronic growth of 2D multilayers. During growth, the heterogenous layer passivates the edges of multilayer 2D island and thus prevents the coalescence of these active edges, while the high interfacial energy between the heterogenous surface layer and the substrate stabilizes the synchronic structure. Based on this model, we have successfully explained the previously observed synchronic growth of graphene and hexagonal boron nitride multilayers (Nat Nanotech 2020, 15: 861; Nature 2022, 606: 88). The deep understanding on the mechanism paves a way towards the synthesis of wafer-scale single-crystal 2D multilayers with a uniform thickness. [ABSTRACT FROM AUTHOR]

MoAlB MAB phase thin films have garnered ever-increasing attention due to their fascinating properties and extensive range of functional applications. Reducing the synthesis temperature of MoAlB thin films is crucial for discerning their limitations and exploring potential applications. In the present study, a strategy was employed to lower the synthesis temperature of the MoAlB thin film by designing (Mo–B)/Al nanostructured multilayers (NMs), which induce the formation of intermetallic compounds as transitional species. The results demonstrated that the synthesis temperature of MoAlB thin films was reduced within the temperature range of 773 K–873 K. The reaction proceeded as expected in two steps: initially, the formation of Al 12 Mo intermetallic compounds took place at the NMs' interface, followed by the subsequent reaction between Al 12 Mo and MoB x , resulting in the formation of the MoAlB MAB phase. Additionally, the MoAlB thin film exhibited a hardness of 16 ± 0.8 GPa and an elastic modulus of 363 ± 13 GPa. Importantly, this work provides valuable insights into achieving the synthesis of MAB phase materials at lower temperatures. [ABSTRACT FROM AUTHOR]

Video question answering (VideoQA) is a challenging video understanding task that requires a comprehensive understanding of multimodal information and accurate answers to related questions. Most existing VideoQA models use Graph Neural Networks (GNN) to capture temporal–spatial interactions between objects. Despite achieving certain success, we argue that current schemes have two limitations: (i) existing graph-based methods require stacking multi-layers of GNN to capture high-order relations between objects, which inevitably introduces irrelevant noise; (ii) neglecting the unique self-supervised signals in the high-order relational structures among multiple objects that can facilitate more accurate QA. To this end, we propose a novel Multi-scale Self-supervised Hypergraph Contrastive Learning (MSHCL) framework for VideoQA. Specifically, we first segment the video from multiple temporal dimensions to obtain multiple frame groups. For different frame groups, we design appearance and motion hyperedges based on node semantics to connect object nodes. In this way, we construct a multi-scale temporal–spatial hypergraph to directly capture high-order relations among multiple objects. Furthermore, the node features after hypergraph convolution are injected into a Transformer to capture the global information of the input sequence. Second, we design a self-supervised hypergraph contrastive learning task based on the node- and hyperedge-dropping data augmentation and an improved question-guided multimodal interaction module to enhance the accuracy and robustness of the VideoQA model. Finally, extensive experiments on three benchmark datasets demonstrate the superiority of our proposed MSHCL compared with stat-of-the-art methods. • We propose a novel hypergraph-based contrastive learning framework MSHCL, which fully explores multimodal representation to achieve better QA. • We design appearance and motion hyperedges to construct the multi-scale temporal–spatial hypergraph, which directly captures higher-order relations among multiple objects. Besides, we use Transformer to capture global information of input sequences. • We design a self-supervised hypergraph contrastive learning task based on node and hyperedgedropping data augmentation and improved QMI module to improve accuracy and robustness of the model. • We conduct extensive experiments on three benchmark datasets to demonstrate the superiority of our proposed MSHCL compared with the state-of-the-art. [ABSTRACT FROM AUTHOR]

We investigate the role strain-induced deoxygenation plays on the observed T c attenuation in multilayers of La 1/3 Ca 1/3 MnO 3 (LCMO) and YBa 2 Cu 3 O 7- δ (YBCO), where a long-range ferromagnetic/superconductor proximity effect is proposed to exist. We compare changes to the superconducting T c in several sets of oxygen-underdoped perovskite/YBCO/perovskite trilayers, where the perovskite layers consist of LCMO; LaNiO 3 (LNO), which is structurally similar to LCMO but non-magnetic; and PrBa 2 Cu 3 O 7- δ (PBCO), which is both non-magnetic and better lattice-matched with YBCO. We find that LCMO and LNO trilayers show similar T c attenuation in response to decreasing annealing pressure. We also use x-ray absorption spectroscopy to directly gauge the hole concentration (p) in LCMO trilayers, where we find both thinner YBCO layers and greater oxygen underdoping decreases p. Our results indicate that strain-induced deoxygenation of the YBCO layer by itself can account for the observed T c attenuation in LCMO/YBCO multilayers. [ABSTRACT FROM AUTHOR]

We revisit a few aspects of the unusual features arising with metamaterials and metasurfaces in the context of their electromagnetic properties. We consider the properties of multilayered structures and indicate that a strong spatial dispersion as well as complex additional boundary conditions arise for a one-dimensional assembly of dielectric layers. With that basis, we analyse nonlinear properties of multilayered structures and illustrate the implications of spatial dispersion for nonlinear properties. Further on, we briefly review the implications of hyperbolic dispersion, readily available with multilayered structures, for nonlinear processes. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

The cyclicity of adsorption processes is crucial for the evaluation of the method as alternative to the extractives commonly used for the separation of petroporphyrins from oil. The adsorption and desorption processes of nickel octaethylporphyrin (Ni-OEP) on coconut shell activated carbon (CSAC) were evaluated under model and real experimental conditions. For the model system, kinetic, equilibrium and thermodynamic studies of adsorption were performed. The characterization of bituminous extract fractions was performed by APPI FT-ICR-MS. The presence of naturally occurring Ni-OEP in the extract was verified. The adsorption mechanisms involved the formation of acid-base and π-π interactions, with preferential adsorption of polar heteroatoms present in the bituminous extract, forming a potentially adsorbent monolayer. The adsorption of Ni-OEP from the extract was favored and about 50 % of the porphyrin present in the extract was recovered. The selective desorption supports the potential of employing sorption processes in the recovery of porphyrins from oil. [Display omitted] • The naturally occurring Ni-OEP in bitumen has been identified by (+) APPI FT-ICR-MS. • Multiporphyrin aggregates adsorbed by π-π interactions were desorbed. • Oxygenated and sulfur compounds from oil extract were chemically adsorbed on CSAC. • The adsorbed polar monolayer enhanced the selective recovery of Ni-OEP molecules. • CSAC is a potential and innovative adsorbent for recovery of Ni-OEP from shale oil. [ABSTRACT FROM AUTHOR]

• The feature pyramids obtained by the top-down and bottom-up combinations are integrated into one feature map. • The integrated feature map is input into a self-attention module to yield the learnt feature map. • Mutual combinations between high and low features and between local and global features enhance the feature representation. In this paper, we propose a feature enhancement method based on multi-scale self-attention, mainly including a multi-scale feature combination module and a self-attention module. The multi-scale feature combination module integrates the multi-layers' features extracted from the backbone network in both the top-down and bottom-up directions. Then, the shallow and deep features are combined. The self-attention module enhances the feature representation by assigning attention weights to the features that have intrinsic connection to the features of the target. The multi-scale self-attention-based feature enhancement method improves the performance for detecting targets with small image sizes in complex scenes by mutual combination between deep and shallow features and between local and global features. The experimental results show the effectiveness of the proposed feature enhancement method. [ABSTRACT FROM AUTHOR]

We investigated the characteristics of F-doped SnO 2 (FTO)/Ag/FTO films prepared using thermal evaporation at room temperature for the application of the as-formed films in transparent thin film heaters (TFHs) of automobiles. To optimize the electrical and optical properties of the FTO/Ag/FTO multi-layer, the figure of merit (FoM) values of the FTO/Ag/FTO multi-layers were compared as a function of the thickness of the Ag and FTO layers. The sheet resistance and optical transmittance of the FTO/Ag/FTO multi-layer were primarily affected by the Ag inter-layer and bottom/top FTO thicknesses, respectively. At optimized Ag (10 nm) and FTO (40 nm) thicknesses, we fabricated a FTO/Ag/FTO electrode with a sheet resistance of 8.00 Ohm/square, an optical transmittance of 83.04 % at a visible wavelength (400–800 nm) and a FoM value of 19.49 Ohm-1. The TFHs comprising the optimal FTO/Ag/FTO electrode exhibited a saturated temperature of 117 °C at a low operating direct current of 6 V, owing to the low sheet resistance. In addition, the FTO/Ag/FTO-based TFHs exhibited thermally stable performances owing to the stability of the bottom and top FTO electrodes. The performance of the FTO/Ag/FTO-based TFHs demonstrated that the thermally evaporated FTO/Ag/FTO multi-layer is a promising, stable, and transparent electrode material for application in the front window TFHs used in automobiles. [ABSTRACT FROM AUTHOR]

An appropriate immune microenvironment, governed by macrophages, is essential for rapid tissue regeneration after biomaterial implantation. The macrophage phenotypes, M1 (inflammatory) and M2 (anti-inflammatory/healing), exert opposing effects on the repair of various tissues. In this study, a new strategy to promote tissue repair and tissue-to-biomaterial integration by M1-to-M2 macrophage transition using artificial apoptotic cell mimetics (phosphatidylserine liposomes; PSLs) was developed using bone as a model tissue. Titanium was also selected as a model substrate material because it is widely used for dental and orthopedic implants. Titanium implants were functionalized with multilayers via layer-by-layer assembly of cationic protamine and negatively charged PSLs that were chemically stabilized to prevent disruption of lipid bilayers. Samples carrying PSL multilayers could drive M1-type macrophages into M2-biased phenotypes, resulting in a dramatic change in macrophage secretion for tissue regeneration. In a rat femur implantation model, the PSL-multilayer-coated implant displayed augmented de novo bone formation and bone-to-implant integration, associated with an increased M1-to-M2-like phenotypic transition. This triggered the proper generation and activation of bone-forming osteoblasts and bone-resorbing osteoclasts relative to their uncoated counterparts. This study demonstrates the benefit of local M1-to-M2 macrophage polarization induced by PSL-multilayers constructed on implants for potent bone regeneration and bone-to-implant integration. The results of this study may help in the design of new immunomodulatory biomaterials. Effective strategies for tissue regeneration are essential in the clinical practice. The macrophage phenotypes, M1 (inflammatory) and M2 (anti-inflammatory/healing), exert opposing effects on the repair of various tissues. Artificially produced phosphatidylserine-containing liposomes (PSLs) can induce M2 macrophage polarization by mimicking the inverted plasma membranes of apoptotic cells. This study demonstrates the advantages of local M1-to-M2 macrophage polarization induced by PSL-multilayers constructed on implants for effective bone regeneration and osseointegration (bone-to-implant integration). Mechanistically, M2 macrophages promote osteogenesis but inhibit osteoclastogenesis, and M1 macrophages vice versa. We believe that our study makes a significant contribution to the design of new immunomodulatory biomaterials for regenerative medicine because it is the first to validate the benefit of PSLs for tissue regeneration. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • An n-type transparent conducting electrode is demonstrated for transparent OLEDs. • The electrode is a multilayer composed of silver between two zinc oxide layers. • Mild sputtering conditions are used to form the electrode to protect the emissive layer. • The electrode exhibits optical and electrical characteristics comparable to those of ITO. Alternative transparent conducting electrodes (TCEs) have gained significant attention in recent decades in an effort to replace costly indium-tin oxide (ITO) in organic optoelectronic devices. For example, state-of-the-art top-emitting and transparent organic light-emitting diodes (OLEDs) in the display industry require a transparent or semitransparent cathode for electron injection. Current OLED display technology employs ultrathin metallic (typically Mg:Ag) layers as semitransparent cathodes. However, recent studies have shown that metal oxide/metal/metal oxide multilayers can perform better optically and offer improved stability compared to semitransparent metal cathodes. Deposition of these multilayers with minimal damage to the underlying organic emissive layer is imperative. Here, we investigate a ZnO/Ag/ZnO TCE multilayer TCE deposited under mild sputtering conditions that are safe for the emissive layer. We demonstrate ∼ 85 % transparent electrodes with a sheet resistance of 1.47 Ω/sq, which is more conductive than the industry standard, ITO. We also integrate the multilayer TCE as the cathode in a transparent OLED device built on ITO, demonstrating the compatibility of this TCE with the existing OLED technology. [ABSTRACT FROM AUTHOR]

A dense and well-adhered Cr coating was prepared on the surface of Zircaloy-4 cladding by arc ion plating. Oxidation tests on Cr-coated Zircaloy-4 claddings were conducted in steam at 700-1300 °C. The surface morphology and cross-sectional microstructure were investigated using SEM, EBSD, FIB and TEM techniques. The results showed that no significant cracking or spalling was observed after oxidation. The oxidized cross-sections showed characteristics of multilayers and interfaces. From the outer to the inner layer, these are, in order, a Cr oxide film and Sn precipitates on its grain boundaries, an amorphous structural layer, a residual Cr coating and (Zr,Cr) x O y oxides on its grain boundaries, a C15-type Zr(Cr,Fe) 2 intermediate layer, and a (Cr,O)-rich substrate Zr. The multilayers and interfaces alter the oxygen diffusion path and reduce the oxygen diffusion rate, thus slowing down the oxidation process of the substrate. In addition, the location and cause of amorphous structures and Kirkendall cavities and their effect on microstructure and adhesion properties were discussed. [ABSTRACT FROM AUTHOR]

In order to realise single on-chip three axis magnetic field sensing technology without the need for convoluted die stacking, perpendicular media must be exploited. This poses additional challenges in both static-bias and the dynamics of the stack. Presented here are ferromagnetic resonance measurements (FMR) on exchange-biased multilayers of IrMn 3 /[Co/Pt] n. We chart the evolution of the different anisotropies caused by both magnetic field annealing and increasing repetition number n. The damping of these stacks does not obey the usual symmetry seen in single and bilayer samples with in-plane anisotropy, but instead follows a sin 2 (θ) dependence. This, we propose, is entirely dominated by spin diffusion from the Co layers into the adjacent heavy metal layers. This is modelled using a simple effective circuit model, providing a guide for the optimisation of complex multilayers. • The evolution of anisotropy in [Co/Pt] multilayers was investigated using FMR. • The damping was dominated by spin-current sinking in adjacent heavy metal layers. • An effective circuit model was proposed to model the parallel damping contributions. [ABSTRACT FROM AUTHOR]

We utilize elevated temperature physical vapor deposition (PVD) techniques to design metal/MAX multilayered nanocomposite thin films with alternating nanoscale metallic (Nb, Ti) and MAX phase (Ti 2 AlC) layer thicknesses. These metal/MAX nanolaminate architectures attempt to exploit a unique hierarchical topology – as interfaces between the layers are expected to be in direct competition with the internal interfaces within the MAX layers, to drive their tunable macroscopic mechanical behavior. Two metal/MAX nanolaminates – Nb/Ti 2 AlC and Ti/Ti 2 AlC – were deposited. The Nb/Ti 2 AlC metal/MAX system showed highly diffused layer interfaces with distinct Ti – rich and Nb–Al – rich layers, with the presence of MAX phase alongside TiC and other Ti–Al and Nb–Al intermetallic phases. The Nb/Ti 2 AlC system possessed a layered architecture, though the MAX phases were not found to be continuously present in each alternating layer. The second Ti/Ti 2 AlC system showed a non-lamellar nanocomposite microstructure and the formation of mixed Ti n+1 AlC n phases (a mix of n = 1, 2), and no indication of layering. Diffusion occurring between the metal/MAX layers in both cases, likely due to the elevated temperatures during the deposition process, is speculated as the likely cause of these resultant microstructures. The mechanical properties of both systems were evaluated using micromechanical (nanoindentation and micro-pillar compression) techniques, which demonstrated high strengths for both systems (Nb system: yield and instability strengths of 4.88 ± 0.1 GPa and 5.57 ± 0.03 GPa, Ti system: yield and instability strength of 5.61 ± 0.28 GPa and 6.21 ± 0.25 GPa). This work highlights the promising mechanical properties of metal/MAX multilayered depositions and summarizes the challenges in PVD synthesis of metal/MAX multilayered nanolaminates. [ABSTRACT FROM AUTHOR]

Spin - valves (SVs) constitute a significant class of magnetic metal structures with a large range of technological applications. This class of structure offers interesting magnetic properties due to their alternation with the non - magnetic layers. The SVs fortunately have good magnetic properties at room temperature (RT). This study intends to use Boltzmann Approach–BA, to treat the magetotransport properties of Co-based SV. Outer - surface scattering effects on magnetoresistance (MR) performance encountered in these structures are investigated by varying the interfacial chemical composition. Analysis of the results reveals the existence of a significant improvement of magnetic phenomenon for a scattering that is more and more specular of the conduction electrons through outer - surface. A giant MR (GMR) of amplitude 136.9 % is obtained for an interfacial geometric roughness of magnitude 2 Å. The GMR ratio is the result of large asymmetry in the spin - dependent interfacial scattering and a completely specular outer - surface scattering. [ABSTRACT FROM AUTHOR]

• The demagnetization time τ D is almost a constant with various substrates. • The magnetization recovery time τ R is significantly influenced by both the seed layers and substrates, ascribed to the spin–lattice coupling. • The experimental data is good agreement with theoretical calculations using the three-temperature model. • The damping parameter α s is independent of K u , but is modulated by both the seed layers and substrates. We systematically investigated the influences of the Pt (Cu) seed layers on the ultrafast demagnetization and magnetization precession of [Co/Ni] 6 multilayers with different substrates (Si, glass, sapphire and ITO glass), respectively, using the time-resolved magneto-optical Kerr effect technique. On the one hand, for the Pt (Cu) seed layers, the demagnetization time τ D is almost a constant with various substrates. It infers that only the magnetic layer dominates the τ D. However, the magnetization recovery time τ R is significantly influenced by both the seed layers and substrates, ascribed to the spin–lattice coupling. The experimental data is good agreement with theoretical calculations using the three-temperature model. On the other hand, the damping parameter α s is independent of K u , but is modulated by both the seed layers and substrates, which is influenced by the spin pump effect and interfacial roughness. The results could be helpful to design the potential application of the high speed spintronic devices. [ABSTRACT FROM AUTHOR]

Poly(vinyl chloride) (PVC), a synthetic polymer, is used in various biomedical applications, particularly in the development of catheters. PVC-based catheters are engineered for blood-contacting applications. However, these materials lack antimicrobial properties, resulting in bacterial proliferation and subsequent infections. To overcome this disadvantage, blood-compatible and antimicrobial polyphenolic tannin-based surface coatings, known as polyelectrolyte multilayers (PEMs), were adsorbed onto PVC for the first time. PEMs were created on reduced PVC (Red-PVC) or oxidized PVC (Oxi-PVC) substrates using the layer-by-layer (LbL) approach. An amino-functionalized polyphenolic tannin derivative (TN-NH 2), commercially known as Tanfloc, and an unmodified polyphenolic tannin (TN), commercially known as Weibull black, were assembled (15 layers) on Oxi-PVC or Red-PVC at pH 5.0. PVC substrates and PEMs were characterized through atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and water contact angle (WCA) measurements. The PEMs showed enhanced wettability compared to the unmodified PVC, with water contact angles ranging from 42° to 38°. The root mean square (R q) roughness of the PEMs ranged from 64.5 nm to 74.1 nm, while the unmodified PVC surface displayed a relatively smooth surface with a roughness of 5.4 nm. Stability tests demonstrated that the PEMs maintained their integrity in phosphate buffer (pH 7.4) over seven days at 37 ° C. The obtained PEMs were not toxic to human fibroblasts and human erythrocytes. The Live/Dead antimicrobial assay results indicated that the PEMs possessed biocidal activity against Pseudomonas aeruginosa (P. aeruginosa) and antiadhesive capacity toward Staphylococcus aureus (S. aureus) and P. aeruginosa after 24 h of incubation. Cytocompatible and antimicrobial tannin-based PEMs on modified PVC surfaces can represent a significant advancement in mitigating bacterial infections associated with PVC-based catheters. • Polyphenolic and amino-functionalized polyphenolic tannins were assembled on poly(vinyl chloride). • The surface coatings are cytocompatible toward fibroblast and red blood cells. • The surface coatings supported outstanding antiadhesive properties. • The surface coatings showed antimicrobial activity against Pseudomonas aeruginosa. • Surface coatings can mitigate bacterial infections associated with catheters. [ABSTRACT FROM AUTHOR]

In this paper, we present a detailed study of the temperature effect (0 − 100 ° C), on the plasmonic resonance and sensitivity of a surface plasmon resonance (SPR) to the medium detection refraction index change. We examine this SPR based on the Kretschmann multilayer configuration constituted by a BK7 prism, an Ag/Au bimetallic layer deposited on TiO 2 /SiO 2 and a BlueP/MoS 2 heterostructure monolayer. First, a simple numerical calculation is provided to analyze the temperature effect on the plasmonic resonance. The model take into account the dependence on temperature of the refractive index of different materials composing the investigated structures. The main idea is to show how the sensitivity of the SPR based sensor is influenced according to operating temperature which is critical parameter when considering bio-sensing applications. [Display omitted] • Study of the temperature effects on the BK7/TiO 2 /SiO 2 /Ag/Au/BlueP-MoS 2 /Sensing-medium biosensor. • Linear shift of plasmon resonance as a function of simultaneously measured temperature and refractive index. • The temperature coefficient sensitivity reaches as high as -1020.41 ppm/°C. • Obtained a sensitivity of 345.42deg/RIU, a value 139.9% higher than the conventional design. • The sensor is able to detect the analyte for a large variation of the refractive index, even at low temperatures. [ABSTRACT FROM AUTHOR]

This study utilizes molecular dynamics simulation to explore the mechanical and friction properties of CuTa/Graphene A/GR multilayers during nanoscratching. By investigating the influence of amorphous layer thickness, substrate temperature, and scratching speed valuable insights into scratching behaviors are gained. Reducing the amorphous layer thickness enhances the normal force and contact pressure, effectively strengthening the A/GR multilayer, while decreasing the frictional force owing to the lubricating properties of graphene, resulting in a notable reduction in friction coefficient. Analysis of the deformation mechanism reveals that the graphene layer impedes shear band propagation, especially noticeable at thinner amorphous layer thicknesses. Additionally, the A/GR multilayer exhibits outstanding wear resistance at high temperature and speed, as indicated by a slightly increased wear atomic ratio. [ABSTRACT FROM AUTHOR]

The effect of epitaxial growth on the mechanical properties of periodic multilayer coatings is an important research topic. The focus of this study is the microstructure and mechanical properties of TiN/CrO x N y periodic multilayer thin films consisting of modulated TiN layers. All samples were prepared by magnetron sputtering with varying sputtering powers for the TiN layer, but the CrO x N y layer remained constant. The grazing incidence X-ray reflectometry (GIXRR) and transmission electron microscopy (TEM) results demonstrate the well-defined periodic structure of the thin films, and an accumulating distortion was observed as more layers were added along the growth direction. The results show that the TiN/CrO x N y multilayers possessed a face-centred cubic (fcc) crystal structure and exhibited a (200) preferred orientation of TiN. The thickness of the TiN layers affected the crystalline orientation of the layers. Alternate-orientation epitaxial growth of CrO x N y layers along the TiN layers occurred when N 2 was introduced. The introduction of nitrogen and the thickness of the TiN template layers significantly influenced the microstructure and crystallinity of the deposited nanomultilayers. The hardness of the multilayer films was determined by the nanoindentation. The TiN/CrO x N y periodic multilayer prepared from the TiN layer by direct current (DC) sputtering power had the highest nano hardness value, 28.7Gpa. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWNTs) are ideal template for constructing one-dimensional (1D) heterojunctions with intriguing optical and electrical properties, yet it remains challenging to wrap foreign materials around SWNTs due to their very small diameter and large curvature. Here, we present a space-confined method to synthesize SWNT bundles wrapped by MoS 2 crystalline layers (SWNT@MoS 2) film by embedding a pristine SWNT film within a porous multi-walled nanotube sponge, which acts as a liquid precursor container for hydrothermal reaction. We find that crystalline MoS 2 sheets could be formed around the outer surface of SWNT bundles uniformly and continuously, with tailored number of multi-layers (3–17 layers), for bundle sizes ranging from several to hundreds of nanometers. The resulting SWNT@MoS 2 network shows much enhanced light response and gas sensitivity, presenting promising applications as flexible photo-detectors and toxic gas sensors. Our scalable synthesis method and SWNT-based coaxial-cables will be useful in future developing innovated 1D van der Waals heterojunctions and flexible nanoelectronic systems. Crystalline MoS 2 sheets could be formed around the outer surface of SWNT bundles uniformly and continuously, for bundle sizes ranging from several to hundreds of nanometers, with 1D vdW structures distinct from previously reported. [Display omitted] • A space-confined method to synthesize SWNT@MoS 2 film by embedding a pristine SWNT film within a porous multi-walled nanotube sponge. • Crystalline MoS 2 sheets could be formed around the outer surface of SWNT bundles uniformly and continuously, with tailored number of multi-layers (3–17 layers), for bundle sizes ranging from several to hundreds of nanometers. • The SWNT@MoS 2 heterojunctions based on SWNT bundles with different sizes are distinct from previously reported 1D vdW structures based on a single SWNT or multi-walled nanotube. • The as-synthesized SWNT@MoS 2 films preserved their original structural flexibility and can be used as flexible sensors and detectors. [ABSTRACT FROM AUTHOR]

The initial report of layered two-dimensional (2D) nitrides and carbides (2D-MXenes) includes multi-layers of molecules in a uniformly arranged or solid assembly manner. Various 2D-MXenes have exposed valuable and adjustable mechanical, optical, electrochemical, and electronic properties, taking the lead to utilizations ranging from electromagnetic interference shielding, medicine, sensing, optoelectronics, energy storage, and catalysis. In this paper, we describe the MXenes synthesis and properties and their potential applications in different fields. In addition, we have highlighted the difficulties, challenges, and prospects of MXenes as well. [Display omitted] • Different synthesis approach of MXenes has been highlighted in-depth discussion. • A general platform on MXenes for different application area has been established. • Scientific gap of this emerging MXene family materials in environmental and medical applications discussed in-depth. • Challenges and perspective future scope of the MXenes has been highlighted. [ABSTRACT FROM AUTHOR]

Using first-principles calculations, we have explored the piezoelectric properties of Janus multilayers and vdW heterostructures based on Janus group-III monochalcogenides. Our calculation results show that all the in-plane and out-of-plane piezoelectricity exists in Janus group-III monochalcogenide multilayers with the atomic radii difference and within intra-layer dipole moments affecting the e 33 / d 33 value. For the vdW heterostructures, the e 33 depends on the stacking configuration and increases with the decreasing interlayer distance. Furthermore, the piezoelectric effect properties of the vdW heterostructures are independent of the biaxial strain. Our understanding of how the layer number and vdW integration affect the piezoelectric effect in 2D materials provides theoretical guidance for the experimental application of 2D Janus monolayer and their vdW heterostructures and will also contribute to the development of robust electrical-mechanical-coupled systems with large power densities and energy harvesting capabilities. [ABSTRACT FROM AUTHOR]

Polyelectrolyte multilayer based nanofiltration membranes can remove organic micropollutants from water. Such polyelectrolyte multilayer membranes (PEMMs) are often assembled on polymeric supports, but less research focuses on inorganic (ceramic) supports. In this work, we assembled symmetric and asymmetric, coatings of poly(allylamine (PAH) and poly(styrene sulfonate) (PSS) on ceramic supports. Symmetric membranes are assembled with the same salt concentration in the coating solution for each layer. Asymmetric membranes use very permeable layers (high salt concentration in coating solution) as base layers and dense top layers with lower permeability (low salt concentration in coating solution) as filtration layers. By reversing the coating order – first salt-free and after that high salt concentration, we obtained reverse asymmetric membranes. They consistently outperformed the symmetric and standard asymmetric design in removing organic micropollutants, reaching an average retention of 85 ± 13 % compared to 77 ± 14 % for the standard asymmetric membranes. We attribute this higher retention to a more efficient pore overcoating for the reverse asymmetric membranes. This work demonstrates that ceramic supports combined with reverse asymmetric PEMMs can be efficiently used for micropollutant removal from water. [Display omitted] • Ceramic membranes are a highly stable support for polyelectrolyte multilayers (PEM). • Varying the salt concentration in the coating solutions results in asymmetric layer structures. • Our reverse asymmetric layer design comprised four thin and four thick bilayers. • These hybrid membranes can remove organic micropollutants (OMPs) from water. • Reverse asymmetric PEM results in high permeability and high OMP retention. [ABSTRACT FROM AUTHOR]

Polyelectrolyte multilayer nanofiltration (NF) membranes have garnered attention for their potential in Mg2⁺/Li⁺ separation applications, particularly due to their positively charged nature and the versatility offered by the layer-by-layer (LbL) self-assembly technique. However, these membranes often face significant challenges in balancing high ion selectivity with adequate water permeability. Addressing these limitations, this study introduces a novel approach by grafting a zwitterionic material, trimethylamine N-oxide (TMAO), onto polyacrylamide hydrochloride (PAH), creating a new cationic polyelectrolyte (TPAH). By cyclically depositing sodium polystyrene sulfonate (PSS) and TPAH onto a polyethersulfone (PES) substrate, we have successfully fabricated a high-performance NF membrane (i.e. , (PSS/TPAH) n) that demonstrates enhanced Mg2⁺/Li⁺ selectivity with high water permeability. TMAO features shorter distances between its positive and negative charge groups and smaller dipoles compared to other zwitterions. These characteristics enhance its ability to resistance to salt effects and transfer charge from amine oxide to water molecule. Furthermore, the grafting of TMAO enhanced the hydrophilicity of TPAH and regulated the charge distribution of the polyelectrolyte. Compared to the control membrane (PSS/PAH) n , the optimized membrane (PSS/TPAH) n showed reduced rejection of LiCl from 60.9 ± 2.7 % to 35.9 ± 1.5 %, while that of MgCl 2 increased from 94.3 ± 1.6 % to 96.1 ± 0.7 %. Additionally, water permeability improved from 9.2 ± 0.9 LMH/bar to 16.1 ± 0.5 LMH/bar. Notably, the membranes exhibited an improved selectivity for Mg2+/Li+ ions in synthetic saline, reaching a maximum of 30.5 ± 1.5, highlighting its potential for practical separation applications. Density functional theory simulations indicate that TMAO not only enhances Donnan effect and intensify ion dehydration of polyelectrolyte multilayers NF membranes but also increases their hydrophilicity. In general, these polyelectrolyte multilayers NF membranes exhibit considerable promise for multiple applications, such as seawater pretreatment, groundwater softening and lithium extraction. [Display omitted] • Polyelectrolyte multilayers nanofiltration membranes were prepared by TMAO grafting. • The modified membrane demonstrated increased water permeability and improved rejection of divalent cations. • Li+/Mg2+ selectivity was achieved benefit by the enhanced Donnan effect and intensive ion dehydration. [ABSTRACT FROM AUTHOR]

MXenes are considered as potential high-performance sodium-intercalation electrode materials. However, the aggregation tendency and low capacity of the pristine MXenes limit their application in sodium-ion batteries (SIBs). Herein, Ti 3 C 2 T x /poly(diallyldimethylammonium chloride)-graphene oxide (Ti 3 C 2 T x /PDDA-GO) multilayers with high specific surface area and expanded layer spacing have been prepared by an electrostatic self-assembly, which provide more accessible electroactive sites and efficient ion transport channels to buffer volume changes during energy conversion. The results show that the Ti 3 C 2 T x /PDDA-GO multilayer electrode has large sodium storage capacity, high initial coulombic efficiency and reversible capacity, and excellent cycle stability and rate performance. Specifically, at a current density of 5 A g−1, the specific capacity remains at 65 mAh g−1 after 1000 cycles. The present work provides a possible strategy for the preparation of MXenes-based materials with high electrochemical performance. Ti 3 C 2 T x /PDDA-GO multilayers were prepared by a simple liquid-phase self-assembly process, which have high specific surface area and stable expansion layer spacing, achieving high initial coulombic efficiency and excellent rate cycling stability in SIBs. [Display omitted] • Ti 3 C 2 T x /PDDA-GO multilayers were fabricated by electrostatic self-assembly. • Achieved high specific surface area and stable expansion of interlayer spacing. • The electrode presented a large capacity and high initial coulombic efficiency. • Exhibited impressive rate performance of 65 mAh g−1 after 1000 cycles at 5 A g−1. [ABSTRACT FROM AUTHOR]

Understanding and control over the self-assembly of molecules is desirable in many physico-chemical processes. Functional groups responsive to a pH change offer immense scope in driving selective molecular self-assembly. pH-dependent self-assembly of an aromatic acid derivative of cholesterol, 4-(6-(cholest-5-ene-3-yloxy)-5-(oxopentyloxy)) benzoic acid, ChBA, is investigated at the air-aqueous interface and characterized using different interface-sensitive techniques. Evidence for the presence of unstable films of ChBA at the air-water interface or for pH < 10 emerges from the surface pressure – area per molecule isotherm, surface pressure relaxation, and Brewster angle microscopy studies. In contrast, for pH > 10.6, ChBA forms a relatively stable film with a higher magnitude of the collapse pressure (45 mN/m). The compressional moduli and the textures obtained using Brewster angle microscopy reveal the presence of two phases (L 1 and L 2), which are also highly stable with temperature. The surface topography of ChBA films transferred from the air-water interface reveals the presence of multilayers of different thicknesses, for film transferred at pH 11 reveals primarily a uniform and homogenous monolayer. Based on the dependence of the collapse pressure with pH , the surface pK a of ChBA is estimated to be about 10.6. Our studies show that the undissociated ChBA spontaneously forms multilayers, whereas partially or fully dissociated ChBA forms distinct and ordered monolayer phases, highlighting the role of electrostatic interactions. [Display omitted] • Langmuir films of an aromatic acid derivative of cholesterol (ChBA) were investigated at different pH. • For pH < 10 (undissociated ChBA), the attractive van der Waals interaction results in the formation of multilayers. • At pH 10.5 (partially dissociated ChBA), monolayer exhibiting L 1 and L 1 ' phases were seen. • At pH 11 (complete dissociation), electrostatic repulsion of ChBA causes the occurrence of stable L 1 and L 2 monolayer phases. • Surface pKa of ChBA was estimated to be 10.6. [ABSTRACT FROM AUTHOR]

Modifying the architecture from a monolithic to a multilayered structure allows adjusting the mechanical properties and cutting performance of industrially relevant hard coatings. The present work focuses on the microstructural, micro-mechanical and cutting performance evaluation of a multilayered TiC 0.67 N 0.33 /TiC coating grown by chemical vapor deposition. Energy dispersive X-ray spectroscopy and atom probe tomography confirmed the presence of individual TiC and TiC 0.67 N 0.33 layers of ∼120 nm thickness with well-defined interfaces. The overall C/(C + N) ratio of the coating amounts to 0.82. Individual peaks for the TiC 0.67 N 0.33 and the TiC layer can be observed in the X-ray diffractogram of the TiCN/TiC coating. Scanning electron microscopy showed that the grains grow through the interfaces between the TiCN and TiC layers. Finally, the micro-mechanical properties and cutting performance of the TiCN/TiC multilayer were compared with a monolithic TiCN coating. The fact that the TiCN/TiC coating outperformed the monolithic reference TiCN in regard of hardness and cutting performance emphasizes the high potential of multilayered coatings for use in demanding applications. • TiCN/TiC multilayer coating with layer thickness of 120 nm grown by CVD. • Increased overall C/(C + N) ratio as compared to state-of-the-art CVD TiCN coatings. • Better hardness and cutting performance in multilayer as compared to reference TiCN. [ABSTRACT FROM AUTHOR]

• Negatively charged MXene Nanosheets are prepared via exfoliation of the MAX phase using HF treatment and the intercalation of DMSO in the sheets using ultra-sonication. • Multi-layered structures with functional groups (-OH, -F, -O) and a hetero-interface between MXene/MnCo 2 O 4 have been synthesized to enhance microwave absorption. • Optimal proportion of the hierarchical structure with a molar ratio of 6:4 for MXene/MnCo 2 O 4 to achieve impedance matching in the composite. • At a loading of 70 wt% the recorded reflection loss is −44.4 dB with 5.114 mm thickness and at 5.14 mm the RL max is −38.55 mm. The great potential for electromagnetic wave (EMW) absorption is revealed in two-dimensional (2D) Ti 3 C 2 T x (MXene) thin sheets that have numerous surface flaws and an extensive spectrum of functional groups. In this study , Ti 3 AlC 2 (MAX Phase) is etched, and then ultrasonic exfoliation is used to create 2D ultrathin Ti 3 C 2 T x nanosheets; a type of MXene. The MnCo 2 O 4 spherical particles were grown on the layered structure of Ti 3 C 2 T x via a one-pot hydrothermal process. The synthesized Ti 3 C 2 T x /MnCo 2 O 4 composite provides superior bulk-to-surface and interfacial charge transfer capabilities due to their short charge transfer distance and extensive interface contact area to the EMW. This article thoroughly evaluates the loss impact in Ti 3 C 2 T x /MnCo 2 O 4 absorbers as -44.4 dB of reflection loss at 16.04 GHz with a thickness of 5.114 mm for the first time, which is essential for fabricating an effective microwave absorber. [Display omitted] [ABSTRACT FROM AUTHOR]

Models are key for geoscientists working in subsurface fold thrust belts, who want to interpret complex geometries. However, models based on a few landmark outcrop studies dominate interpretation. In these models thrust faults form first as flats along weaker beds and propagate upwards, producing a "hard linked", fully connected thrust fault structure. The Eisenstadt and De Paor (1987) model challenges the conventional thrust flat-first, reflecting field observations which show that fold thrust outcrops vary remarkably from each other, with a variety of geometric, linkage, and stratigraphic behaviours. Here we investigate an outcrop of thrusted sediments at St Brides Haven, Pembrokeshire. Structural observations of the outcrop show an imbricated stack, where isolated thrusts have developed within and localised along sandstone layers. The outcrop provides an example of the alternative Eisenstadt and De Paor model of ramps first. But here deformation in the encasing 'soft' mudstone layers is accommodate by homogeneous shortening. We suggest that the prevalence of "hard linked" thrust models is a bias towards conventional models and that promotion of a greater variety of fold thrust structures, geometries and evolution styles is needed to ensure a broader range of interpretations and evolutionary understanding that better reflects reality. • The stratigraphical and structural analysis of St Brides Haven, Pembrokeshire. • Thrust faults initiated as isolated "ramps" in stiff layers. • Faults propagated both up and down through the multilayer. • Thrust ramps are linked by distributed deformation as cleavage in the soft layers. • A supportive case study of Eisenstadt and De Paor's 1987 thrust fault model. [ABSTRACT FROM AUTHOR]

Lithium is one of the key elements in today's materials and battery industry, and the interest in non-destructive characterization techniques at a micron scale for materials containing lithium is steadily increasing. The electron microprobe is a reliable and accessible analysis tool widely used for this purpose, but performing X-ray emission spectroscopy in the low-energy range is still challenging. In this work, we demonstrate that spectroscopy in the Li K energy range is feasible by integrating a new detection system composed of a multilayer and ultra-thin separation windows into a commercial wavelength dispersive spectrometer of a microprobe. The detection system is described in detail, and the results, in form of spectra showing the Li K emission in LiF and in a ternary quasicrystalline sample, are presented and analyzed. In LiF the emission band is centered at 54.5 eV and has varying intensities for different beam exposure times. The spectra obtained in the ternary quasicrystal clearly demonstrate that the detection system has sufficient energy resolution to separate the Li emission band and the Al L 2 , 3 and Cu M 2 , 3 emission bands, enabling chemical state analysis by comparing the shapes of the emissions. To our knowledge, this is the first time such a detection system, implemented in a WDS spectrometer and enabling the acquisition of different Li K spectra in various compounds has been described in detail. This kind of system can be used for Li quantification using a common procedure in electron probe microanalysis. [Display omitted] • Lithium spectroscopy in the Li K range using an electron microprobe is possible. • Equipping microprobe with multilayer/ultra-thin windows allows WDS down to 40 eV. • System's resolution allows separation of the Li emission band from Al L 2,3 emission. [ABSTRACT FROM AUTHOR]

Recently, the development of AlN-based multilayers has raised interest due to the probability of improved performance from both Al-addition and multilayer architecture. Here we prepared AlN/Cr 1- x Al x N (x = 0.44 and 0.64) multilayers, with monolithic AlN and Cr 1- x Al x N coatings as reference. The dependence of microstructure, mechanical properties, thermal stability, oxidation and corrosion resistance on Al content of CrAlN layers were investigated in detail. The AlN/Cr 0.56 Al 0.44 N (low-Al ML) shows a superlattice feature with single-phase face-centered cubic (fcc) structure and its hardness is 29.7 ± 1.0 GPa, which is ∼4.8 GPa higher than the theoretical value from rule of mixture. While the increase of Al content in CrAlN layer leads to a mixed cubic and wurtzite structure of AlN/Cr 0.36 Al 0.64 N (high-Al ML) with semi-coherent interface. Accordingly, the high-Al ML only has a hardness of 16.9 ± 0.4 GPa. During annealing, AlN/Cr 1- x Al x N multilayers reveal hindered decomposition of Cr N bonds, compared with the corresponding Cr 1- x Al x N monoliths. The low-Al ML possesses the best thermal stability, reflected by its high hardness maintained up to 1000 °C, which is 100 °C higher than Cr 1- x Al x N monoliths. Additionally, AlN/Cr 1- x Al x N multilayers show improved oxidation resistance, with high-Al content in CrAlN layers favorable for such resistance. After oxidation at 1100 °C for 15 h, the low-Al ML and high-Al ML generate oxide scales with thicknesses of ∼1.6 and ∼1.4 μm, respectively, compared to the fully oxidized Cr 0.56 Al 0.44 N and ∼1.8-μm-thick oxide scale of Cr 0.36 Al 0.64 N. In electrochemical experiments, the corrosion current density (I corr) of multilayer coatings decreases, compared to their corresponding monolithic coatings. • Cubic CrAlN sublayers stabilize the cubic growth of wurtzite AlN sublayers. • Increasing Al content induces interfacial transition from coherent to semi-coherent. • Construction of multilayer structure enhances the thermal stability of coating. • The oxidation resistance of multilayer coating is dominated by the Al content. [ABSTRACT FROM AUTHOR]

Interface stress is a fundamental descriptor for interphase boundaries and is defined in strict relation to the interface energy. In nanomultilayers with their intrinsically high interface density, the functional properties are dictated by the interface structure, which is governed by the delicate interaction of residual interface and volume stresses. In the present work, experimental estimations of the interface stress in Cu/W NMLs were compared with corresponding theoretical values as calculated using DFT (adopting an incoherent bcc W{110}/fcc Cu{111} interface with variable in-plane strain). The Cu/W interface stress was experimentally tuned monotonically from positive to negative values by changing the residual stress in the W nanolayers. Qualitative agreement between experiment and simulation was achieved, confirming a decrease of the interface stress from the compressive to the tensile regime. The DFT simulations showed that Cu atoms at the strained Cu/W interfaces are displaced along the in-plane and out-of-plane directions in response to the interface stress. Using a preliminary neural network potential for the Cu–W system, specific in-plane crystallographic orientation relationships for the Cu/W interfaces were also tested, which improved quantitative agreement between experiment and theory. Assumptions and limitations in experiments and theory for deriving the interface stress are critically discussed. [Display omitted] • Interface stress in Cu/W multilayers is assessed theoretically and experimentally. • Effect of the in plane stresses on atoms at the interface is investigated. • Agreement between experiment and simulation is critically discussed. • Different crystallographic orientations affect the interface stress. [ABSTRACT FROM AUTHOR]

Non-line-of-sight (NLOS) imaging techniques have garnered significant interest in recent years for their ability to reconstruct obscured scenes. This type of imaging typically needs numerous temporal histograms, which require thousands of scans on the relay surface. Reconstructing obscured targets using several channels, i.e., capturing echoes from a few positions of the relay surface, is an attractive prospect but has so far been restricted to localization applications. Herein, we propose a rectangle-based data-driven method and first demonstrate that the 2D size of the hidden target can be detected even with as few as 2 or 3 detectors by exploiting the information inside an echo signal. Specifically, we conceptualize the occluded target as a rectangle representing the target size and train a multi-layer perceptron to learn the correspondence of the hidden scene from the generated data, in which the method can directly respond to unknown targets. Both numerical simulations and experiments are performed to evaluate the feasibility of this method. Furthermore, this work provides a feasible way of detecting hidden scene without scanning. [Display omitted] Reconstructing obscured objects using several channels without scanning is an attractive prospect but has thus far been restricted to localization applications. Herein, we propose a rectangle-based data-driven method which conceptualize the occluded target as a rectangle, and first demonstrates that the 2D size of the hidden target can be detected even with as few as 2 or 3 detectors by exploiting the information inside an echo signal. (a) shows a schematic diagram of the hidden scene, where P L is left bound the target and B L i is the left side of the box. (b) represents the recorded temporal histograms which contains information about the obscured target, where t P c is the closest ToF of the hidden target on the histogram, and t P f is the farthest ToF of the hidden target. (c) is a photo of the hidden scene. (d) is a depth image of the hidden scene as a front view, generated by the rectangle-based (multi-layers perceptron) MLP. • Proposes a rectangle-based data-driven method to associate echoes and target size. • Reconstructs the non-line-of-sight target 2D size using few detection channels. • Conceptualizes the occluded target as a rectangle representing the target size. • Provides a feasible way of detecting hidden scene using fixed laser and few detectors. [ABSTRACT FROM AUTHOR]

The present work is devoted to the study of the non-equilibrium properties of 3D switchable spin-crossover (SCO) multi-layers by accounting for lattice frustration effects and elastic anisotropy. The investigations are performed using an extended version of the original electro-elastic model which includes the lattice volume change at the spin transition between the low-spin (LS) and the high-spin (HS) states. The numerical simulations were made using Monte Carlo (MC) Metropolis technique for the spin state subsystem, combined with a semi-analytical method of mechanical relaxation of the lattice positions, which revealed to be very efficient in terms of computational time. To enhance the quality of the results, the scattered lattice positions were interpolated using the radial basis functions method. The 3D character of the simulations allows the molecules to leave the plane of the 2D layers, thus leading to corrugations and buckling which considerably relax the elastic strain. Various configurations of elastic interactions are then studied, among which, those accounting for anisotropic elastic constants and others including an intrinsic elastic frustration in the LS state. As a result, multi-stepped low-temperature relaxation processes are reproduced for the temporal evolution of the metastable HS fraction, displaying the emergence of complex self-organizations of the spin states and structure in the plateaus regions. In addition to the usual checkerboard antiferro-like HS–LS patterns, spontaneous spatial self-organization into alternated HS and LS layers are also obtained, recalling experimental data of Fe-picolylamine and other compounds of literature, which remained an open theoretical problem to date. [Display omitted] • Development of a very efficient method for the mechanical relaxation • Anisotropic elastic constants inducing multi-stepped transient self-organization • Intrinsic elastic frustration stabilizes the spin states self-organization. • Alternating HS and LS layers, similar to experimental data, are obtained. • Predicted of a 3D antiferro-like coupled HS–LS stripes self-organization. [ABSTRACT FROM AUTHOR]

Thin-film encapsulation (TFE) with strong barrier properties is essential for dependable flexible display. Hybrid Al 2 O 3 and polymer multi-layered structures are considered the most promising TFE technology. However, hydrolysis of Al 2 O 3 becomes severe with increased temperature and humidity, threatening the reliability of TFE. In this work, Alucone is introduced in the Al 2 O 3 /NEA multi-layers, where the Alucone can serve as a hydrolysis inhibition layer, to improve its reliability. In addition, Al 2 O 3 is permeated into the NEA polymer to further improve the barrier performance of Al 2 O 3 /NEA multi-layers. The results show that the insertion of Alucone can inhibit effectively the hydrolysis of Al 2 O 3 in the accelerated test environment. The complete interfacial infiltration of Al 2 O 3 into NEA polymer can further improve the barrier performance. The water vapor transmission rates of (Al 2 O 3 /Alucone) 3 /NEA (named AAN composite films) can reach 0.27 × 10−6 g/m2/day. The barrier performance of AAN composite films remains robust even after bending tests and stability examinations. The OLED encapsulated by the AAN composite films, only less than 10 % brightness decline occurs after 7 days, illustrating that AAN composite films can extend the lifetime of OLED. The results demonstrate that the AAN composite films is anticipated to hasten the commercialization of flexible displays. • The complete interfacial infiltration of Al 2 O 3 into NEA polymer by using ALI process can further improve the barrier performance. • The water vapor transmission rates of AAN composite films can reach 0.27 × 10−6g/m2/day. • The barrier performance of AAN composite films remains robust even after bending tests and stability examinations. • The OLED encapsulated by the AAN composite films, only less than 10 % brightness decline occurs after 7 days. [ABSTRACT FROM AUTHOR]

Perovskite compounds including sesquioxide materials have recently gained popularity in optical biosensing due to their high chemical stability and excellent semiconducting properties. These properties make perovskite materials an ideal platform for optical detection. In this line, this paper presents new real-time ultrasensitive plasmonic biosensor for large molecule detection based on metal/porous graphene/perovskite material (MPGP). The performance of the proposed device is reported in terms of the variety of perovskite media such as In 2 O 3 and BaSnO 3 materials and the nature of pores incorporated in the multilayer graphene which plays the role of amplifier medium. It is observed that the sensitivity of this device increases from 684nm/RIU using BaSnO 3 to 948nm/RIU using sesquioxide In 2 O 3. Whereas the quality factor reaches the maximum value Q = 74.5 for the porosity P = 7 % with BaSnO 3 while Q = 9275 for (P = 28 %) with In 2 O 3. However, the limit of detection is around 6 μM. Moreover, the proposed device exhibits an optical sensing region that can be adjusted by varying their electrical and geometrical parameters to meet the requirements of desired molecule detection. • A structure chalcogenide prism/metal/porous graphene/perovskite material ABO 3 is proposed to detect some bio-substance (protein molecules) such as amide I and amide II • This study passed by several steps. • Firstly, a theoretical model is developed using cole-cole equation, the Drude-Lorentz model and the Kubo formula. • Then the results are found using the Transfer Matrix Method (TMM), the FDTD technique and the Kretschmann configuration. • Finally, the performance of the proposed biosensor is studied in terms of sensitivity, selectivity and Limit of detection. • The results show that the proposed device is a good detector of proteins [ABSTRACT FROM AUTHOR]

• A fast though accurate modeling strategy is presented to treat non-uniform atmospheres. • A functional form, based on physical and statistical arguments, is derived to handle path non-uniformities. • Evaluation of the unknown coefficients of the model (Lévy–Khintchine representation) relies on regression on LBL data. • The proposed method is shown to provide highly accurate results at a very low CPU cost. The objective of the present work is to describe a technique to approximate atmospheric path transmissivities using a recurrent structure, following a method proposed recently but limited to date to high temperature applications. The physical model together with its underlying statistical assumptions is detailed. It is found to involve a rather simple analytical formula that applies both to two-layers systems and to more general multi-layers non-uniform configurations. This treatment of path non-uniformities uses several unknown parameters that are first trained on LBL reference data in two-layers configurations to illustrate the relevance of the proposed approximate model. Then, in a second time, model's parameters are trained on non-uniform path transmission curves representative of multi-layers atmospheres. The corresponding recurrent formulation is shown to provide accurate estimates of transmissivities of non-uniform atmospheric paths (maximum relative errors are below 0.35 % in all the considered test cases) at a very low CPU cost. [ABSTRACT FROM AUTHOR]

The hardness and fracture toughness of high-temperature wear-resistant transition metal aluminum nitride multilayer films depend largely on the constituting layer's structure, compositional modulation, morphology, and interface coherency. We present a study on 1-micron thick multilayered films consisting of stacked layers of TiN and Zr 0.37 Al 0.63 N 1.09 , each layer being 10 nm thick. The films were grown using ion-assisted reactive magnetron sputtering on MgO(001) and Si(001) at substrate temperatures ranging from ambient to 900°C. By increasing growth temperature, we found that the ZrAlN layers transition from near amorphous to nanocrystalline wurtzite to decomposed c-ZrN and w-AlN domains. Concurrently, the TiN layers exhibit strong fiber texture, polycrystallinity, and epitaxial growth carried by the ZrN domains. Both hardness and fracture stress, evaluated by nanoindentation and micromechanical tests, increase with temperature from H=24 GPaMgO, 23 GPaSi to 36 GPaMgO, 30 GPaSi, and σ F Si= 6.1-7.7 GPa, respectively. An improved fracture toughness of K IC =2.4-2.8 MPa√m is related to different toughening mechanisms for the various microstructures. The difference in hardness between the substrates is related to compressive stress due to the deposition conditions and thermal contraction. The superior fracture stress is attributed to dense multilayers, free from macroscopic defects due to ion-assisted growth. After being deposited at 200°C, the multilayers remained thermally stable when vacuum annealed for 15 hours at 900°C, with no significant change in phase composition or hardness. The improved hardness, toughness, and temperature stability of the otherwise brittle nitrides are promising for industrial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Metallic additive manufacturing (AM) offers near net-shape fabrication but often results in insufficient strength and/or ductility due to voids or cracks, coarse initial crystalline microstructure, insufficient volume fraction of precipitates and yet post-AM strengthening/toughening methods non-destructive to shape are generally lacking. Here, we report a laser-directed energy deposited (L-DED) medium entropy alloy (MEA) with a heterostructure (HS) comprising alternate layers of solid-solution and intermetallic-dispersed MEA that possess ultimate tensile strength of 1132.8 MPa and elongation of 50.6 %, corresponding to strength-ductility synergy higher than other medium- or high-entropy alloys reported. The multilayers were produced from a dual source of CoCrNi MEA powder and a powder mixture of the same MEA, Al and Ti with stoichiometry (CoCrNi) 86 Al 7 Ti 7 , and the remarkable strength-ductility synergy is achieved only after post-L-DED heat treatment, which causes Al and Ti to diffuse across the layers to form a low-gradient HS. The significant back stress due to the HS contributes to the high strength, while the high ductility results from a high strain-hardening rate suppressing necking. This study demonstrates the concept of using AM not just as a near net-shape fabrication method but also a unique tool to produce low-gradient HSs with superb mechanical properties, via the use of multiple powder sources combined with suitable shape-preserving post-fabrication heat treatment. [Display omitted] • A layered heterostructure medium entropy alloy was fabricated by laser directed energy deposition. • The gradient distribution of L1 2 and σ phases at the layer interface is realized by heat treatment. • The synchronous improvement of strength and ductility results from precipitation hardening and back stress strengthening. [ABSTRACT FROM AUTHOR]

This study addresses the pressing issues of groundwater depletion and drought problems in the Erbil basin, a vital resource region in the Middle East. Focused on an area of strategic importance due to its large size and critical water resources, the study employs the Groundwater Modeling System (GMS) software to create a detailed 3D hydrogeological model based on extensive borehole data. With over 240 boreholes analyzed, the study strategically selects 70 accurate wells drilled by the Groundwater Directorate. The construction of the 3D stratigraphic models for the Erbil basin relies on three main historical data including boreholes, geological formations and a comprehensive approach, incorporating deep well logging data and the definition of distinct geological layers. By discerning the presence of previous and impervious layers, the model effectively categorizes the aquifer types within the Erbil basin. The aquifer system is delineated based on stratigraphic units, designating materials with high conductivity (silt, sand, and gravel) as aquifers and clay (or claystone) as aquitards. A 3D steady-state groundwater flow model is successfully executed, employing PEST pilot point for automated parameter estimation. The model, validated with a coefficient of determination (R2) of 0.9998, reveals hydraulic conductivity values ranging from 0.000980705 to 100 m/day and a recharge value of 0.000976443 m/day. The study classifies Erbil's aquifer types as unconfined, confined, and semi-confined, providing a valuable foundation for groundwater management. The primary objective of this study is to construct a calibrated numerical groundwater model for the multi-aquifer system in the Erbil basin. The model aims to serve as a robust tool for analyzing the sustainability of diverse groundwater infrastructure development strategies within the region. The Erbil basin poses unique challenges for groundwater modeling, marked by a scarcity of critical data such as monitoring well information, pumping rates, recharge rates, and flow budgets. In response to these limitations, the study adopts an innovative approach by integrating in situ data with earth observation data. The integration of these datasets seeks to overcome data constraints and enhance the accuracy of the groundwater model. By achieving calibration and validation of the numerical model, this research strives to provide a valuable resource for decision-makers, planners, and stakeholders involved in groundwater management in the Erbil basin. Ultimately, the study aims to contribute to the development of sustainable and effective strategies for the utilization and preservation of groundwater resources in this vital region and also to enhance practical management strategies for the Erbil groundwater basin, ensuring sustainable utilization of the crucial sub-surface water resources, an objective successfully achieved through this research. [ABSTRACT FROM AUTHOR]

• We study the dependence of the size and stability, for an ideal magnetic skyrmion bags in a cylindrical ultrathin nanodot, on the varying applied magnetic field. • By adjusting the magnetic parameters of the materials, the stability of skyrmion bags can be significantly enhanced. • Our results will provide valuable insights for the experimental development of magnetic multilayers tailored for devices based on skyrmion bags. Size and stability of magnetic skyrmion bags in a cylindrical ultrathin nanodot under the influence of an applied magnetic field are investigated. Micromagnetic calculations reveal unique characteristics in the behavior of skyrmion bags across various materials. By adjusting the magnetic parameters of the materials, the stability of skyrmion bags can be significantly enhanced. We believe that our results will provide valuable insights for the experimental development of magnetic multilayers tailored for devices based on skyrmion bags. [ABSTRACT FROM AUTHOR]