Amorphous Structure Research Articles

The GPAT4/6/8 clade functions in Arabidopsis root suberization nonredundantly with the GPAT5/7 clade required for suberin lamellae

Lipid polymers such as cutin and suberin strengthen the diffusion barrier properties of the cell wall in specific cell types and are essential for water relations, mineral nutrition, and stress protection in plants. Land plant-specific glycerol-3-phosphate acyltransferases (GPATs) of different clades are central players in cutin and suberin monomer biosynthesis. Here, we show that the GPAT4/6/8 clade in Arabidopsis thaliana, which is known to mediate cutin formation, is also required for developmentally regulated root suberization, in addition to the established roles of GPAT5/7 in suberization. The GPAT5/7 clade is mainly required for abscisic acid-regulated suberization. In addition, the GPAT5/7 clade is crucial for the formation of the typical lamellated suberin ultrastructure observed by transmission electron microscopy, as distinct amorphous globular polyester structures were deposited in the apoplast of the gpat5 gpat7 double mutant, in contrast to the thinner but still lamellated suberin deposition in the gpat4 gpat6 gpat8 triple mutant. Site-directed mutagenesis revealed that the intrinsic phosphatase activity of GPAT4, GPAT6, and GPAT8, which leads to monoacylglycerol biosynthesis, contributes to suberin formation. GPAT5/7 lack an active phosphatase domain and the amorphous globular polyester structure observed in the gpat5 gpat7 double mutant was partially reverted by treatment with a phosphatase inhibitor or the expression of phosphatase-dead variants of GPAT4/6/8. Thus, GPATs that lack an active phosphatase domain synthetize lysophosphatidic acids that might play a role in the formation of the lamellated structure of suberin. GPATs with active and nonactive phosphatase domains appear to have nonredundant functions and must cooperate to achieve the efficient biosynthesis of correctly structured suberin.

Combination of carboxymethylcellulose and wood hemicelluloses to enhance encapsulation efficiency and microcapsule wall thickness

Wood hemicelluloses have been used as a wall material for spray-dried microencapsulation of polyphenols. Nevertheless, their incomplete water solubility could negatively impact their encapsulation efficiency (EE) and the formation of a complete protective layer, which might be alleviated synergistically by combining them with carboxymethylcellulose (CMC). Here, we explored the effects of CMC addition (0.5–3.0 %, w/w of WM) on the capacity of galactoglucomannans (GGM) and glucuronoxylans (GX) to retain bioactive compounds of bilberry during spray drying; and its contribution to the formation of wall thickness. The results revealed that EE of GGM and GX increased by 4–8 % with the CMC addition at 0.5 %, but significantly declined at higher CMC concentrations. Adding CMC improved the microcapsules' antioxidant activities, surface smoothness, and solubility, but had no effect on their particle size, thermal properties, amorphous structure, or moisture content. The majority of the GGM and GX microcapsules had a hollow internal structure surrounded by continuous wall matrix with a thickness of about 2.3–2.6 μm, which increased to 3.1–3.5 μm with the addition of 0.5 % CMC. Therefore, using CMC at an optimized proportion as a co-encapsulant improved wood hemicelluloses' ability to protect bioactive compounds during spray drying and enhanced microcapsule wall formation.

Optimization of pullulan production by Aureobasidium pullulans using semi-solid-state fermentation and artificial neural networks: Characterization and antibacterial activity of pullulan impregnated with Ag-TiO2 nanocomposite

This study presents a novel and efficient approach for pullulan production using artificial neural networks (ANNs) to optimize semi-solid-state fermentation (S-SSF) on faba bean biomass (FBB). This method achieved a record-breaking pullulan yield of 36.81 mg/g within 10.82 days, significantly exceeding previous results. Furthermore, the study goes beyond yield optimization by characterizing the purified pullulan, revealing its unique properties including thermal stability, amorphous structure, and antioxidant activity. Energy-dispersive X-ray spectroscopy and scanning electron microscopy confirmed its chemical composition and distinct morphology. This research introduces a groundbreaking combination of ANNs and comprehensive characterization, paving the way for sustainable and cost-effective pullulan production on FBB under S-SSF conditions. Additionally, the study demonstrates the successful integration of pullulan with Ag@TiO2 nanoparticles during synthesis using Fusarium oxysporum. This novel approach significantly enhances the stability and efficacy of the nanoparticles by modifying their surface properties, leading to remarkably improved antibacterial activity against various human pathogens. These findings showcase the low-cost production medium, and extensive potential of pullulan not only for its intrinsic properties but also for its ability to significantly improve the performance of nanomaterials. This breakthrough opens doors to diverse applications in various fields.

The Effects of Si Substitution with C on the Amorphous Forming Ability, Thermal Stability, and Magnetic Properties of an FeSiBPC Amorphous Alloy

The Effects of Si Substitution with C on the Amorphous Forming Ability, Thermal Stability, and Magnetic Properties of an FeSiBPC Amorphous Alloy

Formation of 2D Amorphous Lithium Sulfide Enabled by Mo2C Clusters Loaded Carbon Scaffold for High-Performance Lithium Sulfur Batteries.

Lithium-sulfur (Li-S) batteries, operated through the interconversion between sulfur and solid-state lithium sulfide, are regarded as next-generation energy storage systems. However, the sluggish kinetics of lithium sulfide deposition/dissolution, caused by its insoluble and insulated nature, hampers the practical use of Li-S batteries. Herein, leaf-like carbon scaffold (LCS) with the modification of Mo2C clusters (Mo2C@LCS) is reported as host material of sulfur powder. During cycles, the dissociative Mo ions at the Mo2C@LCS/electrolyte interface are detected to exhibit competitive binding energy with Li ions for lithium sulfide anions, which disrupts the deposition behavior of crystalline lithium sulfide and trends a shift in the configuration of lithium sulfide toward an amorphous structure. Combining the related electrochemical study and first-principle calculation, it is revealed that the formation of amorphous lithium sulfides shows significantly improved kinetics for lithium sulfide deposition and decomposition. As a result, the obtained Mo2C@LCS/S cathode shows an ultralow capacity decay rate of 0.015% per cycle at a high mass loading of 9.5mg cm-2 after 700 cycles. More strikingly, an ultrahigh sulfur loading of 61.2mg cm-2 can also be achieved. This work defines an efficacious strategy to advance the commercialization of Mo2C@LCS host for Li-S batteries.

Magnetic Anisotropy in Heterogeneous Amorphous Thin Films: Insights from Thickness and Temperature-Driven Spin-Reorientation

Abstract Magnetization orientation in thin films is intricately influenced by multiple anisotropy components, with the dominant anisotropy serving as a key determinant. This complexity becomes particularly intriguing when considering thin films composed of subnanometer-scale heterogeneous amorphous structures. Our investigation builds upon this foundation, specifically focusing on the Fe-Ni-B-Nb alloy system, known for its moderate glass-forming ability and susceptibility to nanocrystallization. In this study, we present thickness- and temperature-driven spin-reorientation (SRT) transition, attributed to competing magnetic anisotropy energies in thin films featuring a heterogeneous amorphous structure. Thermogravimetric investigations unveiled a unique heterogeneous amorphous structure, a revelation unattainable through conventional structural analysis methods. The observed spontaneous perpendicular magnetization in amorphous films, as evidenced by transcritical hysteresis loops and magnetic stripe domains, is ascribed to the pronounced residual stress arising from the substantial magnetostriction of the alloy system. The temperature-driven SRT is correlated to the order-disorder magnetic transition of the heterogeneous amorphous phase, characterized by a Curie temperature of ~225 K. This transformative magnetic state of the heterogeneous amorphous matrix limits the exchange interaction among the densely distributed α-Fe nuclei regions, ultimately governing the dynamic magnetic responses with varying temperature. This work provides valuable insights into the dynamic magnetic orientation of thin films, especially those with heterogeneous amorphous structures, contributing to the broader understanding of the underlying mechanisms of magnetization reversals.

Bimetallic Metal-Organic Framework-Derived porous One-Dimensional carbon materials for electrochemical sensing of dopamine

In this work, we report the preparation of one-dimensional (1D) bimetallic zinc-cobalt BTC (BTC = 1,3,5-benzenetricarboxylate) metal–organic frameworks (MOFs) with varying Zn/Co ratios and their conversion to hierarchical porous Co/C hybrids with a trace amount of Zn (<0.05 wt%). The crystallinity, surface area, and degree of graphitization of the resulting Co/C hybrid are governed by the Zn/Co ratio of the parent Zn-Co BTC MOF. The Co/C product derived from the Zn-rich Zn-Co BTC MOF (ZC31-BTC with a Zn/Co precursor ratio of 3:1) shows higher surface area and more amorphous structure than that derived from the Co-rich Zn-Co BTC MOF (ZC13-BTC with a Zn/Co precursor ratio of 1:3). When used for the electrochemical sensing of dopamine (DA), the glassy carbon electrode (GCE) modified with ZC31-BTC700°C (ZC31-BTC carbonized at 700 °C) shows a sensitivity of 0.0995nA nM−1 cm−2, a wide linear range of 0.1–500 µM, and a low limit of detection (LoD) of 0.04 µM (signal-to-noise ratio (S/N) = 3). The superior DA sensing performance of ZC31-BTC700°C is attributed to its high density of defects (evidenced by the high ID/IG ratio), rich mesopores (including small (<5 nm) and large mesopores (>5 nm)), and high surface area, leading to improved ion/electron transfer (based on the EIS analysis), and more electrochemically active sites (confirmed by ECSA measurements) to promote a greater oxidation of DA molecules. The anti-interference test of this ZC31-BTC700°C-modified GCE (ZC31-BTC700°C/GCE) indicates its high selectivity toward DA even in the presence of interferents, such as glucose, ascorbic acid, and uric acid. Moreover, the stability test indicates the good retainment of the current response of ZC31-BTC700°C/GCE toward DA over a period of 2 weeks.

Green-process preparation and characterizations of optically transparent, thermally stable and mechanically superior regenerated silk-hyaluronate composite films

High-performance regenerated silk-hyaluronate composite films prepared by an environment-friendly process were highly desirable for medical dressing base material. In this study, sericin was removed from silk by steam treatment without using any chemical reagent, and a low concentration solution of Na2CO3 was used as a green process to dissolve silk fibers. Then the obtained silk fibroin was physically blended with sodium hyaluronate to generate optically transparent, thermally stable and mechanically superior regenerated silk-hyaluronate films. The results of structural characterizations and property tests showed that the insoluble silk short fibers prepared by the dissolution of Na2CO3 were dominated by a β-sheet crystalline structure while the soluble silk fibroins by an amorphous structure. Moreover, both insoluble silk short fibers and soluble silk fibroins could form uniform composite films with a low coefficient of thermal expansion after being blended with sodium hyaluronate, which were named as insoluble silk film (ISH) and soluble silk film (SSH), respectively. The tensile strength of ISH could reach 138.8 MPa and SSH reached 153.9 MPa, which were 65.7 % and 30.5 % higher than that of the commercial control insoluble fibroin film (83.8 MPa) and commercial control soluble fibroin film (117.9 MPa), and 173.2 % and 203.0 % higher than that of pure hyaluronate film (50.8 MPa), respectively. Also, ISH and SSH had a modulus higher than 3 GPa. In this study, the low-concentration Na2CO3 method provides a simple and green technique for the preparation of high performance silk-hyaluronate composite materials.

Structure and corrosion properties of multilayer metal/nitride/oxide ceramic coatings formed on austenitic-martensitic steel by magnetron deposition

The design of protective coatings preventing the degradation and failure of austenitic steels in humid climate is a relevant issue. In this work, a conventional magnetron sputtering method was utilized in order to fabricate a four-layer Ni/Al-Si-N/Ni/Al-Si-O coating onto austenitic-martensitic steel. At the first stage of deposition, a three-layer coating was formed in an Ar+N2 atmosphere using a mosaic target (Ni or Al-Si), while the second stage included the deposition of the outer ceramic Al-Si-O layer in an Ar+O2 gas mixture. The studies of the structure, hardness, adhesion strength and electrochemical behavior (in 3.5 wt. % NaCl) of the «coating/steel» system were performed by means of X-ray Diffraction, electron microscopy, mechanical (indentation and scratch) tests and electrochemical impedance spectroscopy. The ceramic Al-Si-O layer exhibits an amorphous structure. The adjacent nickel layers have submicrocrystalline columnar grains. The ceramic Al-Si-N layer possesses a nanocrystalline columnar structure based on AlN + Si3N4 phases. Hardness behavior of the multilayer coating varies nonmonotonically due to a contribution of the soft amorphous phase in the upper surface layer and high-strength nanocrystalline phases in the underlying sublayers. It has been revealed that as-deposited multilayer coating decreases a corrosion rate of the substrate. The layered structure of the coating hinders the transport and diffusion of chloride ions to the substrate and decreases the corrosion rate of the substrate. However, a transport of chloride ions into the inner layers of the coating may occur through the microstructural defects preserved in the amorphous Al-Si-O layer. The scheme describing an initiation of corrosion damage and formation of corrosion products under critical corrosion conditions was proposed.

Edible antibacterial gelatin/zein fiber films loaded with cinnamaldehyde for extending the shelf life of strawberries by electrospinning approach

Strawberries are a kind of nutritious fruit but they are easily spoilt by mold. Therefore, it is significant to prolong the shelf life of strawberries for the avoidance of their numerous wastes. To achieve the aforementioned objective, in this paper, the edible and biodegradable natural polymers of gelatin/zein were used to prepare the antibacterial fiber films loaded with cinnamaldehyde by electrospinning method. The fibers prepared in this study were smooth and bead-free, with the average diameters ranging from 1.46 to 2.02 μm. The successful encapsulation of cinnamaldehyde in obtained fiber films was confirmed by Fourier transform infrared spectra. The prepared fiber films decomposing at about 230 °C were shown by thermogravimetric analysis curves, indicating their high thermal stability. The amorphous structure of the polymers in the produced fiber films was displayed by X-ray diffraction curves. Compared with the untreated strawberries, strawberries treated with fiber films encapsulated with 15 wt.% and 20 wt.% cinnamaldehyde showed the smallest changes in appearance, weight loss rate, hardness, pH, and total soluble solids at 6 d. The shelf life of strawberries was increased to 6 days by the fiber films containing 15 wt.% and 20 wt.% cinnamaldehyde. The fiber films prepared in this study were potentially expected to be used as edible antibacterial packaging films, nutrient and drug carriers.

Construction of Fe-based amorphous active surface microenvironment and its synergistic Fenton-like treatment of organic pollutants

Fe-based amorphous materials with the superiorities of high efficiency and low Fe sludge secondary pollution can be seen as a potential alternative to Fenton catalysts. However, catalyst deactivation on the catalyst surface hinders the sustainability of high degradation activity. In this study, the degradation capabilities of FeBCCr amorphous alloys in methylene blue (MB) solution by Fenton-like method were explored. The optimum (Fe81B10C9)99Cr1 ribbon with a more uniform Fe3B-like amorphous structure, which exhibits a thin and easily-peeled oxide layer, provides unique dynamic self-renewing to obtain excellent efficiency and recyclability. The degradation rate with 0.05 g/L (Fe81B10C9)99Cr1 ribbon reached 0.248 min−1 and the recyclability reached a charming record of over 90 times with a dosage of 0.1 g ribbon. The activation energy of (Fe81B10C9)99Cr1 ribbon (12.97 kJ mol−1) was found to be superior to that of most metallic catalysts. More importantly, the boron-rich film in the interfacial region can both retard further oxidation of iron and provides a channel for electron transmission, which can contribute to the persistence of a highly active microenvironment with more Fe(Ⅱ) sites and highly utilization of H2O2. The limit segmentation method has verified the good performance in both heterogeneous and homogeneous reactions. This study introduces a strategy for designing high-performance non-noble metallic catalysts through cluster structure regulation, which provides a novel Fenton-like amorphous material with long recyclability of high degradation activity for water remediation.

Contrastive study on mechanical and microstructure properties of silt improved by nano material stabilizers

Silt is generally stabilized with industrial waste for subgrade filler material. However, problems such as high cost, poor water stability, and easy shrinkage hinder the use of industrial waste-stabilizing materials. Experiments are conducted to compare the effect of nano-silica (NS) and nano-MgO (NM) on the unconfined compressive strength (UCS) of silt. It is undertaken by stabilized silt with NM and NS in four different concentration grades of NM(S)-3, NM(S)-4, NM(S)-5, NM(S)-6 ( 0.3%, 0.4%, 0.5%, 0.6% by weight of silt). XRD, FT-IR, and SEM tests are carried out to discern the latent mechanisms so that the mineral composition and pore structure within the soil matrix can be explained. The results demonstrate that the increase in different grades of nano-MgO and nano-silica stabilized silt plays an important role in improving the mechanical properties of the silt. Nano-silica is more conducive to strength and water resistance enhancement due to the formation of ettringite and C-S-H gel. Nevertheless, a small amount of nano-MgO can better improve the water stability of stabilized silt in the early stage. Optimal results are obtained for silt treated with NS-5 (2% cement, 2% GGBS, 1% FA, 0.5% nano-silica) and NM-5 (2% cement, 2% GGBS, 1% FA, 0.5% nano-MgO). XRD, FT-IR, and SEM analysis of the samples show, respectively, that the amorphous (C-S-H) structure and the soil particles embedded in the cementitious matrix comprise the strength of the silt. Nano-MgO is mainly involved in carbonation and pozzolanic reactions. The cement hydration reaction and ettringite formation, which unite smaller particles to produce larger particles, are enhanced by the addition of SiO2. In summary, this paper recommends the use of nano-MgO to improve the early strength of stabilized silt, and the use of nano-silica to improve the long-term strength.

Preparation of Zr-based metallic glasses gradient composites with designable amorphous fraction by laser powder bed fusion

Introducing ductile crystals in situ into the matrix is an efficient approach for enhancing the mechanical properties of bulk metallic glasses (BMGs). However, controlling the volume of the crystalline phase is challenging, and the introduction of crystals may be detrimental to its strength and ductility trade-off. In addition, BMGs prepared by conventional casting process suffers from the disadvantages of size limitation, inhomogeneous crystallization, and uncontrollable crystallization fraction. In this study, Zr48Cu47.5Al4Co0.5 amorphous powder with better forming ability was utilized as raw material and printed by selective laser melting (SLM) technique with high cooling rate. Through parameter adjustments and proactive design of amorphous fractions, gradient metallic glasses (GMGs) based on Zr has been successfully prepared. Micro-morphology, DSC tests, micro-area XRD, optical calculations and nanoindentation experiments all indicate the presence of gradient structures. The microstructure reveals that the crystalline phases in the heat affected zone (HAZ) are mainly B2 phase. In addition, the results of room temperature compression show that the yield strength (1.2 GPa) and plastic deformation (0.8 %) of the gradient structure are better than those of the samples prepared with a single parameter. The theme of amorphous fraction gradient structure design, realized by SLM technology, opens a new window for the large-scale development of high-performance BMGs.

Boosting Contact Electrification By Amorphous Polyvinyl Alcohol Endowing Improved Contact Adhesion and Electrochemical Capacitance.

Ion conductive hydrogels are relevant components in wearable, biocompatible and biodegradable electronics. Polyvinyl-alcohol (PVA) homopolymer is often the favoured choice for integration into supercapacitors and energy harvesters as in sustainable triboelectric nanogenerators (TENGs). However, to further improve hydrogel-based TENGs, a deeper understanding of the impact of their composition and structure on devices performance is necessary. We show ionic hydrogels based on an amorphous-PVA (a-PVA) allowing to fabricate TENGs that outperform the one based on the homopolymer. When used as tribomaterial, the Li-doped a-PVA allows to achieve a 2-fold higher pressure sensitivity compared to PVA, and to develop a conformable e-skin. When used as an ionic conductor encased in an elastomeric tribomaterial, 100mW/cm2 average power is achieved, providing 25% power increase compared to PVA. At the origin of such enhancement is the increased softness, stronger adhesive contact, higher ionic mobility (> 3,5-fold increase), and long-term stability achieved with Li-doped a-PVA. These improvements are attributed to the high density of hydroxyl groups and amorphous structure present in the a-PVA, allowing a strong binding to water molecules. This work discloses novel insights on thoseparameters allowing todevelopeasy-processable,stable and highly conductive hydrogels for integration in conformable, soft and biocompatible TENGs. This article is protected by copyright. All rights reserved.

A comparison between solvent casting and electrospinning methods for the fabrication of HPMC fast-dissolving films: investigation of the physicochemical, mechanical and drug release characteristics

The fast-dissolving film is an innovative dosage form that rapidly delivers the loaded drug upon contact with saliva. Many studies have been conducted on the fabrication of fast-dissolving films using hydroxy propyl methyl cellulose (HPMC) as a common film-forming agent with solvent-casting method or sometimes with electrospinning. However, there is no comparison of these two methods on the physicochemical, mechanical, and drug-release behavior of HPMC films. This paper aims to compare bisoprolol-containing fast-dissolving films composed of HPMC and polyethylene glycol (PEG) as plasticizer constructed by solvent-casting and electrospinning methods. Given the formulation parameters (e.g., plasticizer and polymer concentrations) and process parameters (e.g., tip-to-needle distance, voltage, and feed rate), various solvent-casting films and nanofiber mats were prepared. Films were characterized in terms of disintegration time, folding endurance, thermal behavior (using DSC), crystallin structure (using XRD), drug content, and drug release. The size and morphology of nanofibers were also evaluated by SEM. Solvent-casting film composed of 6% w/v HPMC and 6% v/v PEG400, as well as nanofiber mat composed of 13% w/v HPMC and 3% w/v PEG2000 were successfully constructed. DSC and XRD analysis revealed that the crystalline structure of bisoprolol converted into the amorphous structure in the polymeric films. Nanofibers were smooth and free of beads with a mean size of 0.66 ± 0.19 μm. In terms of flexibility, the nanofiber mats outperformed the solvent-casting films. The disintegration time of the nanofiber mat was less than that of the solvent-casting film (3 s versus 30 s). Besides, nanofibers indicated faster release. The superior performance of nanofiber mats can be attributed to their nanostructure. The results showed that the characteristics of the fast-dissolving films fabricated of HPMC, including disintegration time, release rate, and flexibility could be improved through the electrospinning process.

Structure and optical properties of Si thin film improved by metal Cd nanolayers

AbstractEnhancing the characteristics of amorphous semiconductor thin films is imperative for a multitude of applications. The present study examines the impact of Cd nanolayers deposited on a thin film of amorphous Si. The X-ray test showed that the thin silicon film had less of an amorphous structure after a nanolayer of cadmium was added. There has also been the appearance of new phases, and as the thickness of the Cd nanolayer increases, so does the intensity of these phases. Using a field emission scanning electron microscope, it was seen that nanoparticles were developed and subsequently transformed into clusters as the thickness of the Cd nanolayer grew. The absorbance was maximized at 750 nm and near-infrared region after depositing Cd nanolayers, while transmittance was reduced, especially at 100 nm thicknesses. The energy gap was reduced, with a decrease from 5.1 to 1.8 electron volts (eV). However, an increase in the band tails was also noted, rising from 0.7 to 4.9 eV. An increase in the values of the refractive index (n) and extinction coefficient (k) was observed following the deposition of Cd nanolayers of different thicknesses.

Catalytic Oxidation of Chlorobenzene over Amorphous Manganese-Chromium Catalysts Supported by UiO-66-Derived ZrOx.

The development of efficient catalysts with longevity to remove chlorobenzene is challenging due to Cl poisoning. Herein, a series of Mn-Cr/ZrOx catalysts supported by Zr-based metal-organic framework (UiO-66)-derived ZrOx was prepared and investigated for chlorobenzene (CB) catalytic oxidation. MnCr/ZrOx-M prepared via a wet impregnation method presented an amorphous structure, indicating the homogeneous dispersion of Cr and Mn, which improved acid and redox properties. 40Mn7Cr3/ZrOx-M exhibited the best catalytic activity for chlorobenzene oxidation with T90 of 293 °C, which is mainly due to the strong interaction between manganese and chromium promoted by the large specific surface area of the ZrOx support. Furthermore, 40Mn7Cr3/ZrOx-M presented excellent stability for chlorobenzene oxidation.

Spin Seebeck effect and large spin conversion in amorphous Fe2TiSb/polycrystalline Y3Fe5O12 thin films

This study investigates spin current generation in a Fe2TiSb/Y3Fe5O12 multi-layer thin film as prepared via the magnetron sputtering method. Comprehensive characterization techniques are employed to assess film properties, including X-ray diffraction, energy-dispersive X-ray spectroscopy, Scanning electron microscopy, and Vibrating sample magnetometer. The Y3Fe5O12 material exhibits a polycrystalline ferromagnetic insulator behavior, while the 20 nm-thick Fe2TiSb film displays small ferromagnetic metal properties with an amorphous structure. Spin current analysis utilizes the longitudinal spin Seebeck effect configuration, considering magnetic field and temperature dependencies and the results show that spin conversion within the Fe2TiSb/Y3Fe5O12 structure is influenced by both the spin Seebeck effect and the anomalous Nernst effect, resulting in an overall spin signal enhancement. The spin Seebeck coefficient of Fe2TiSb/Y3Fe5O12 was approximately 0.103 μV/K within a magnetic field of 300 mT.

Study on crystal to amorphous transition of nickel-based alloy processed by ultra-short pulsed laser shock peening

The main purpose was to investigate the process of crystal to amorphous transition in nickel-based alloy subjected to ultra-short pulsed laser shock peening. A molecular dynamics model of laser shock peened nanopolycrystalline nickel-based alloy was established using LAMMPS. The influence of shock velocity on the amorphous transformation in nickel-based alloy was analyzed. The results indicated that ultra-short pulsed laser shock peening with ultra-high strain rate plastic deformation promoted the increase and accumulation of defect for nickel-based alloy, contributing to the formation of amorphous structures.

Engineering a Hierarchy of Disorder: A New Route to Synthesize High-Performance 3D Nanoporous All-Carbon Materials*.

We report a new nanoporous amorphous carbon (NAC) structure that achieves both ultrahigh strength and high electrical conductivity, which are usually incompatible in porous materials. By using modified spark plasma sintering, we create three amorphous carbon phases with different atomic bonding configurations. The composite consists of an amorphous sp2-carbon matrix mixed with amorphous sp3-carbon and amorphous graphitic motif. NAC structure has isotropic electrical conductivity of up to 12,000 S/m, a Young's modulus of up to ∼5GPa, and Vickers hardness of over 900MPa. These properties are superior to those of existing conductive nanoporous materials. Direct investigation of the multiscale structure of this material through transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), and machine learning-based electron tomography revealed that the origin of the remarkable material properties is the well-organized sp2/sp3 amorphous carbon phases with a core-shell-like architecture, where the sp3-rich carbon forms a resilient core surrounded by a conductive sp2-rich layer. Our research not only introduces novel material with exceptional properties, but also opens new opportunities for exploring amorphous structures and designing high-performance materials. This article is protected by copyright. All rights reserved.