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China Antimicrobial Resistance Surveillance Network for Pets (CARPet) was established in 2021 to monitor the resistance profiles of clinical bacterial pathogens from companion animals. From 2018 to 2021, we recovered and tested 4,541 isolates from dogs and cats across 25 Chinese provinces, with Escherichia coli (18.5%) and Staphylococcus pseudintermedius (17.8%) being the most predominant bacterial species. The Enterobacterales were highly susceptible to tigecycline, meropenem, colistin, and amikacin (70.3%–100.0%), but showed moderate resistance to ampicillin, ceftriaxone, doxycycline, florfenicol, levofloxacin, enrofloxacin, and trimethoprim-sulfamethoxazole (29.3%–56.7%). About 66.3% of Acinetobacter spp. were resistant to florfenicol, with relatively low resistance to another 11 antibiotics (1.2%–23.3%). The Pseudomonas spp. showed high susceptibility to colistin (91.7%) and meropenem (88.3%). The coagulase-positive Staphylococcus spp. showed higher resistance rates to most antimicrobial agents than coagulase-negative Staphylococcus isolates. However, over 90.0% of Staphylococcus spp. were susceptible to linezolid, daptomycin and rifampin, and no vancomycin-resistant isolates were detected. E. faecium isolates demonstrated higher resistance rates to most antimicrobial agents than E. faecalis isolates. Streptococcus spp. isolates showed low resistance to most antimicrobial agents except for doxycycline (78.2%) and azithromycin (68.8%). Overall, the tested clinical isolates showed high rates of resistance to commonly used antimicrobial agents in companion animals. Therefore, it is crucial to strengthen the monitoring of bacterial resistance in pets. By timely and effectively collecting, analyzing, and reporting antimicrobial resistance dynamics in pets, the CARPet network will become a powerful platform to provide scientific guidance for both pet medical care and public health.

Under near-ambient pressure conditions, carbon monoxide molecules intercalate underneath an epitaxial graphene monolayer grown on Ni(111), getting trapped into the confined region at the interface. On the basis of ab-initio density functional theory calculations, we provide here a full investigation of the intercalated CO pattern, highlighting the modifications induced on the graphene electronic structure. For a CO coverage as low as 0.14 monolayer (ML), the graphene layer is spatially decoupled from the metallic substrate, with a significant C 1s core level shift towards lower binding energies. The most relevant signature of the CO intercalation is a clear switching of the graphene doping state, which changes from n-type, when strongly interacting with the metal surface, to p-type. The shift of the Dirac cone linearly depends on the CO coverage, reaching about 0.9 eV for the saturation value of 0.57 ML. Theoretical predictions are compared with the results of scanning tunnelling microscopy, low-energy electron diffraction and photoemission spectroscopy experiments, which confirm the proposed scenario for the nearly saturated intercalated CO system. This result opens the way to the application of the graphene/Ni(111) interface as gas sensor to easily detect and quantify the presence of carbon monoxide.

We have studied zirconia films on a Rh(111) substrate with thicknesses in the range of 2–10 monolayers (ML) using scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED). Zirconia was deposited using a UHV-compatible sputter source, resulting in layer-by-layer growth and good uniformity of the films. For thicknesses of 2–4 ML, a layer-dependent influence of the substrate on the structure of the thin films is observed. Above this thickness, films show a (2 × 1) or a distorted (2 × 2) surface structure with respect to cubic ZrO2(111); these structures correspond to tetragonal and monoclinic zirconia, respectively. The tetragonal phase occurs for annealing temperatures of up to 730 °C; transformation to the thermodynamically stable monoclinic phase occurs after annealing at 850 °C or above. High-temperature annealing also breaks up the films and exposes the Rh(111) substrate. We argue that the tetragonal films are stabilized by the interface to the substrate and possibly oxygen deficiency, while the monoclinic films are only weakly defective and show band bending at defects and grain boundaries. This observation is in agreement with positive charge being responsible for the grain-boundary blocking effect in zirconia-based solid electrolytes. Our work introduces the tetragonal and monoclinic 5 ML-thick ZrO2 films on Rh(111) as a well-suited model system for surface-science studies on ZrO2, as they do not exhibit the charging problems of thicker films or the bulk material and show better homogeneity and stability than the previously-studied ZrO2/Pt(111) system.

A novel quantitative optical diagnostics method for determining the threshold of soot onset in counterflow diffusion flames was proposed and demonstrated. The method was based on the proportional discrimination of trichromatic luminescence and the nonparametric and unsupervised automatic threshold selection algorithm. The macroscopic soot onset threshold in ethylene diffusion flame with three ethyl esters additions could be precisely determined. It was found that the undesirable soot onset phenomenon for ethylene diffusion flames was significantly suppressed with ethyl ester addition. The method proposed here will be useful as a reference for soot diagnostics in other flames.

The key to achieve a certain goal for Cyber Physical Systems is coordination of system tasks. By analyzing the characteristics of CPSs, an approach for task decomposition was proposed. This approach uses design structure matrix (DSM) to describe the relationship of the tasks, decomposes tasks by decoupling and recombination according to the degree of coupling between atomic tasks. Furthermore, the task process model based on Petri net is constructed for the decomposed sub-tasks, and the relationship of sub-tasks is graphically shown, which provides a theoretical basis for the task execution and scheduling and dynamic reorganization of CPSs resources.

Osteoarthritis (OA) is a progressively degenerative disease of joints. In vitro culture of chondrocytes results in dedifferentiation, which is characterized by the development of fibroblast phenotypes, reduced ability to produce cartilage extracellular matrix (ECM) and increase the expression of molecular markers Col1a1, Col10a1 and Runx2. Redifferentiation of chondrocytes is indicated by increased expression of the molecular markers Col2a1, Aggrecan and Sox9. In the current study, we investigated the effects of allogeneic rabbit adipose-derived mesenchymal stem cells (ADSCs) on articular chondrocytes, and explored the therapeutic effect of ADSCs on damaged articular cartilage at different stages in a rabbit OA model. In vitro, the proliferation and migration of primary articular chondrocytes were enhanced by cocultured rabbit ADSCs, and the expression of redifferentiation markers in chondrocytes cocultured with ADSCs was increased at both the mRNA and protein levels, while the expression of dedifferentiation markers was decreased. In vivo, the rabbit model of OA was established by anterior cruciate ligament transection (ACLT) with complete medial meniscectomy (MMx). Two weeks after surgery, ADSCs were used for OA rabbit treatment. Intra-articular injection of ADSCs gradually alleviated articular cartilage destruction, decreased Osteoarthritis Research Society International (OARSI) and Mankin scores, and reduced MMP13 expression at different stages in the rabbit model of OA. During the experiment, allogeneic ADSCs did not cause any adverse events. The current study demonstrates the effects and molecular mechanisms of ADSCs on articular chondrocytes and provides a favorable reference for clinical OA treatment with mesenchymal stem cells (MSCs) derived from adipose tissue.

An operando investigation of graphene growth on (100) grains of polycrystalline nickel (Ni) surfaces was performed by means of variable-temperature scanning tunneling microscopy complemented by density functional theory simulations. A clear description of the atomistic mechanisms ruling the graphene expansion process at the stepped regions of the substrate is provided, showing that different routes can be followed, depending on the height of the steps to be crossed. When a growing graphene flake reaches a monoatomic step, it extends jointly with the underlying Ni layer; for higher Ni edges, a different process, involving step retraction and graphene landing, becomes active. At step bunches, the latter mechanism leads to a peculiar 'staircase formation' behavior, where terraces of equal width form under the overgrowing graphene, driven by a balance in the energy cost between C-Ni bond formation and stress accumulation in the carbon layer. Our results represent a step towards bridging the material gap in searching new strategies and methods for the optimization of chemical vapor deposition graphene production on polycrystalline metal surfaces., Comment: 23 pages including title page and references, 4 figures

Moiré superstructures are common for epitaxial graphene on transition metal surfaces and can strongly influence the mechanical and electronic properties of the overgrown film. To date, most of the reported investigations have focused on the moiré patterns on sixfold close-packed substrates, where the superstructures also exhibit hexagonal modulations. Herein, graphene moiré patterns on a fourfold Ni(100) surface have been investigated on the basis of a simple geometric model assuming the existence of coincidence lattices. The moiré motif changes from stripes to rhombic networks as the misorientation angle between graphene and the substrate increases. The unit cells of the observed moiré superstructures are described within a matrix formalism, allowing the lattice parameters to be accurately determined. In all cases, the graphene lattice was found to be anisotropically strained in order to obtain commensurability in the moiré supercells. Our work for the first time determines the atomic configurations for a variety of graphene moiré superstructures on a fourfold substrate, on the basis of a coincidence lattice model. The resulting atomic-scale details will serve as a reference for future experimental and theoretical studies of this specific system and will shed light on the geometric and strain analysis of two-dimensional films supported by a symmetry-mismatched surface.

Interface strain can significantly influence the mechanical, electronic and magnetic properties of low-dimensional materials. Here we investigated by scanning tunneling microscopy how the stress introduced by a mismatched interface affects the structure of a growing graphene (Gr) layer on a Ni(100) surface in real time during the process. Strain release appears to be the main factor governing morphology, with the interplay of two simultaneous driving forces: on the one side the need to obtain two-dimensional best registry with the substrate, via formation of moir\'e patterns, on the other side the requirement of optimal one-dimensional in-plane matching with the transforming nickel carbide layer, achieved by local rotation of the growing Gr flake. Our work suggests the possibility of tuning the local properties of two-dimensional films at the nanoscale through exploitation of strain at a one-dimensional interface., Comment: 17 pages, 3 figures

Recent years have witnessed great advances in graphene coatings for improving the conductivity and cycling performance of non-carbonaceous anode materials (e.g., metal oxides, Si and Ge) towards advanced lithium-ion batteries (LIBs). However, the ubiquitously-used, chemically-exfoliated graphene wrapping layers within LIBs still face daunting challenges in the limited electronic transport and uncontrolled solid electrolyte interphase growth, which lead to the degradation of reversible capacity and cycling stability. Herein, we demonstrate an ingenious chemical vapor deposition strategy to realize in-situ conformal growth of graphene on MnO nanorods mediated by methane carburization. Fundamentally different from the chemically-exfoliated counterparts, the thus-grown graphene layers exhibit highly tunable crystallinity and thickness to optimize charge transport for the hermetically-isolated MnO anode materials from electrolyte. In turn, the graphene shell-isolated MnO anode manifests the enhanced stability over long-term cycling and rate capability, as compared to the previous MnO-based counterparts. Our work would provide a novel insight into the state-of-the-art design of high-rate and long-life graphene/metal oxide-based electrodes targeting future-generation LIBs.

Lateral quantum confinement is of great interest in tuning the electronic properties of graphene-based nanostructures, making them suitable for technological applications. In principle, these properties might be controlled through the edge topology: for example, zigzag nanoribbons are predicted to have spin-polarized edge states. The practical realization of these structures is of utmost importance in fully harnessing the electronic properties of graphene. Here, the formation of regular, 1.4 nm wide ribbon-like graphene structures with zigzag edges are reported, showing 1D electronic states. It is found that these “pseudo-ribbons” embedded in single-layer graphene supported on Ni(100) can spontaneously form upon carbon segregation underneath 1D graphene moiré domains, extending hundreds of nanometers in length. On the basis of both microscopy/spectroscopy/diffraction experiments and theoretical simulations, it is shown that these structures, even though seamlessly incorporated in a matrix of strongly interacting graphene, exhibit electronic properties closely resembling those of zigzag nanoribbons.

X-ray photoelectron spectroscopy (XPS) of five-monolayer-thick ZrO2 films reveals a core level binding energy difference of up to 1.8 eV between the tetragonal and monoclinic phase. This difference is explained by positively charged oxygen vacancies in the tetragonal films, which are slightly reduced. Due to the large band gap of zirconia (≈5-6 eV), these charges shift the electron levels, leading to higher binding energies of reduced tetragonal films w.r.t. fully oxidized monoclinic films. These core level shifts have the opposite direction than what is usually encountered for reduced transition metal oxides. The vacancies can be filled via oxygen spillover from a catalyst that enables O2 dissociation. This can be either a metal deposited on the film, or, if the film has holes, the metallic (in our case, Rh) substrate. Our study also confirms that tetragonal ZrO2 is stabilized via oxygen vacancies and shows that the XPS binding energy difference between O 1s and Zr 3d solely depends on the crystallographic phase.

Interaction with the substrate strongly affects the electronic/chemical properties of supported graphene. So far, graphene grown by chemical vapor deposition (CVD) on catalytic single crystal transition metal surfaces - mostly 3-fold close-packed - has mainly been studied. Herein, we investigated CVD graphene on a polycrystalline nickel (Ni) substrate, focusing in particular on (100) micrograins and comparing the observed behavior with that on single crystal Ni(100) substrate. The symmetry-mismatch leads to moiré superstructures with stripe-like or rhombic-network morphology, which were characterized by atomically-resolved scanning tunneling microscopy (STM). Density functional theory (DFT) simulations shed light on spatial corrugation and interfacial interactions: depending on the misorientation angle, graphene is either alternately physi- and chemisorbed or uniformly chemisorbed, the interaction being modulated by the (sub)nanometer-sized moiré superstructures. Ni(100) micrograins appear to be a promising substrate to finely tailor the electronic properties of graphene at the nanoscale, with relevant perspective applications in electronics and catalysis. Fil: Zou, Zhiyu. The Abdus Salam. International Centre for Theoretical Physics; Italia Fil: Carnevali, Virginia. Università degli Studi di Trieste; Italia Fil: Jugovac, Matteo. Università degli Studi di Trieste; Italia. Helmholtz Gemeinschaft. Forschungszentrum Jülich; Alemania. The Abdus Salam. International Centre for Theoretical Physics; Italia Fil: Patera, Laerte L.. Helmholtz Gemeinschaft. Forschungszentrum Jülich; Alemania. Vienna University of Technology; Austria Fil: Sala, Alessandro. Università degli Studi di Trieste; Italia Fil: Panighel, Mirco. Helmholtz Gemeinschaft. Forschungszentrum Jülich; Alemania. Università degli Studi di Trieste; Italia Fil: Cepek, Cinzia. Università degli Studi di Trieste; Italia Fil: Soldano, Germán. Helmholtz Gemeinschaft. Forschungszentrum Jülich; Alemania Fil: Mariscal, Marcelo. Università degli Studi di Trieste; Italia Fil: Peressi, Maria. Universitat Regensburg; Alemania Fil: Comelli, Giovanni. Laboratorio Nazionale Tasc; Fil: Africh, Cristina. Università degli Studi di Trieste; Italia

Direct growth of graphene on traditional glasses is of great importance for various daily life applications. We report herein the catalyst-free atmospheric-pressure chemical vapor deposition approach to directly synthesizing large-area, uniform graphene films on solid glasses. The optical transparency and sheet resistance of such kinds of graphene glasses can be readily adjusted together with the experimentally tunable layer thickness of graphene. More significantly, these graphene glasses find a broad range of real applications by enabling the low-cost construction of heating devices, transparent electrodes, photocatalytic plates, and smart windows. With a practical scalability, the present work will stimulate various applications of transparent, electrically and thermally conductive graphene glasses in real-life scenarios.

To meet the rising demand of graphene in electronics and optoelectronics, developing an efficient synthesis strategy for effective control of the layer thickness is highly necessary. Herein, we report the synthesis of strictly single-layer graphene on the foil of an early transition metal, tungsten (W), via a simple chemical vapor deposition route. The cracking of hydrocarbons is facilitated by the catalytically active metal surface of W, while the subsequent two-dimensional growth is mediated by the carbide-forming ability within the underlying bulk, leading to the formation of uniform monolayer graphene. The as-grown graphene layers can be transferred onto target substrates rapidly through the recently developed electrochemical method, which also allows for reuse of the substrates at least five times without introducing quality deterioration. Moreover, considering the refractory nature of W foils, a complementary component of nickel is added, by means of which the growth temperature of graphene can be significantly reduced. In brief, a highly-efficient and low-cost synthesis route has been developed for the growth of graphene towards large-area uniformity, single-layer thickness and high crystalline quality.

The bottom-up assembly of chiral structures usually relies on a cascade of molecular recognition interactions. A thorough description of these complex stereochemical mechanisms requires the capability of imaging multilevel coordination in real-time. Here we report the first direct observation of hierarchical expression of supramolecular chirality at work, for 10,10′-dibromo-9,9′-bianthryl (DBBA) on Cu(111). Molecular recognition first steers the growth of chiral organometallic chains and then leads to the formation of enantiopure islands. The structure of the networks was determined by noncontact atomic force microscopy (nc-AFM), while high-speed scanning tunnelling microscopy (STM) revealed details of the assembly mechanisms at the ms time-scale. The direct observation of the chirality transfer pathways allowed us to evaluate the enantioselectivity of the interchain coupling.

We demonstrate a method to control the distribution of magnetic Co ions in Co-doped SnO2 nanorods by the surfactant. The nanorods with nanoflower morphology have been synthesized by surfactant-assisted hydrothermal method. The X-ray absorption fine structure spectra at Co K-edge reveal that Co ions substitute for Sn site in SnO2 lattice. The X-ray absorption fine structure spectra at O K-edge with its simulated spectra have been performed to investigate the local environment of Co ions. In the experimental spectra, the pre-edge peak continues to decline with the addition of the surfactant. It shows the same trend when the number of clustered Co ions in the simulated spectra is reduced, which indicates that the surfactant suppresses the formation of Co clusters. The effect of surfactant in mediating Co distribution arises from the strong interactions between the Co2+ ions and the CTA+ ions. In the Co K-edge experimental spectra, the weakened pre-edge peak reflects the electron transfer from the CTA+ ions to Co 3d band. Such electron transfer changes the charge state of Co ions and modifies the electrostatic interactions among dopant ions, leading to the uniform distribution of substitutional Co dopants. These results provide experimental guidance in the synthesis of the homogeneous-doped metal oxide semiconductors.

CuO films have been fabricated by a two-step method: depositing Cu films on single crystal Si substrates by magnetron sputtering; thermal oxidation of the as-deposited Cu films in the air at 600 degrees C. To investigate the effect of magnetic field on CuO film growth, a series of static fields are added along the substrate in the oxidation process. Field emission scanning electron microscopy shows that the high magnetic field promotes the densification and the grain refinement of the films. The X-ray diffraction results reveal that the films have monoclinic structure of CuO. The relative intensity of (111) peak strengthens gradually with increasing the magnetic field intensity, implying that the magnetic field facilitates the growth along [111] direction. X-ray photoelectron spectra of Cu 2p core-level indicate that +2 is the main valence state for Cu ions in CuO films, and the magnetic field produces deeper oxidation of the samples. The high binding energy part of O 1s XPS spectra, which reflects the oxygen adsorption ability, shrinks at low magnetic field, and then expands with the further increase of the magnetic field. The mediation of oxygen adsorption is related to the improvement of crystallinity as well as the enlarged boundary areas. The present study opens a new way to fabricate CuO films, and the high magnetic field is an effective way to tuning the oxygen adsorption.

Mass production of high-quality graphene with low cost is the footstone for its widespread practical applications. We present herein a self-limited growth approach for producing graphene powders by a small-methane-flow chemical vapour deposition process on naturally abundant and industrially widely used diatomite (biosilica) substrates. Distinct from the chemically exfoliated graphene, thus-produced biomorphic graphene is highly crystallized with atomic layer-thickness controllability, structural designability and less noncarbon impurities. In particular, the individual graphene microarchitectures preserve a three-dimensional naturally curved surface morphology of original diatom frustules, effectively overcoming the interlayer stacking and hence giving excellent dispersion performance in fabricating solution-processible electrodes. The graphene films derived from as-made graphene powders, compatible with either rod-coating, or inkjet and roll-to-roll printing techniques, exhibit much higher electrical conductivity (∼110,700 S m−1 at 80% transmittance) than previously reported solution-based counterparts. This work thus puts forward a practical route for low-cost mass production of various powdery two-dimensional materials., High-volume, low-cost production of graphene is pivotal for the industrial advance of this 2D material. Here, the authors make use of naturally occurring diatomite as a 3D substrate for graphene growth, obtaining non-planar porous graphene structures after removal of the silica templates.

The microstructure and defect evolution of Co-doped SnO2 nanostructures have been mediated by the surfactant via a hydrothermal method. The microstructure is characterized by X-ray diffraction and Raman spectra in detail. It is found that the density of structural defects considerably increases with the increase of the surfactant amount used in the preparation process. Meanwhile, the orange emission enhances dramatically. The growth process and defect evolution have been investigated by the following time-dependent experiments. Due to the existence of hollow scrolls in the growth, the mesocrystal lamellar attachment and the rolling process are proposed for the possible growth mechanism. In the synthetic process, surfactant cations, which are incorporated into the network of the self-assembled structure, strongly interact with tin hydroxyl anions. After removing the surfactants by calcination, the vacancies create in the corresponding locations, which promote the orange emission. Our finding opens a new way to control SnO2 defects and strength the optical emission.

Cobalt ferrite (CoFe2O4) nanowire arrays with different diameters were prepared in porous anodic aluminum oxide (AAO) template by a sol-gel template method. A magnetic field annealing procedure was performed in the direction along wire axis (out of sample planes) at 600°C under 10-T applied magnetic field to orient the spinel CoFe2O4 crystalline. The morphology was studied by scanning electron and transmission electron microscope. X-ray diffraction (XRD) patterns show that samples performed by the magnetic field annealing procedure have a 〈110〉 texture along the nanowire axis, while those annealed without applied magnetic field show a nonoriented polycrystalline phase of spinel type structure. Vibration sample magnetometer (VSM) test shows the difference between CoFe2O4 nanowire arrays samples annealed with or without applied magnetic field. This difference shows the magneto-crystalline anisotropy with the easy magnetization direction along the nanowire axis, and is caused by the resultant effect of the easy magnetization direction distribution of the crystalline.

FeCoB nanocomposites coated with FeCo-oxide layers were synthesized by a simple wet chemical method. Postannealing treatment was carried out from 400°C to 600°C. TEM observations show that the FeCoB particles have an average diameter of several tens of nanometer. The FeCoB nanoparticles are coated with 3 nm thick FeCo-oxide layers, exhibiting good core/shell structure. X-ray diffraction analysis demonstrates that the samples have bcc FeCo structure. A maximum saturation magnetization of 173.9 emu/g and a minimum coercivity of 169.1 Oe are obtained. Microwave absorption measurements show that the as-synthesized FeCoB nanocomposites exhibit a minimum reflection loss (RL) of -29.3 dB at the frequency of 13.2 GHz. Bandwidths of 4.1 GHz (11.0-15.1 GHz) for an RL of -20 dB and 7.4 GHz (9.1-16.5 GHz) for an RL of -10 dB are estimated, respectively.

Early transition metals, especially groups IVB-VIB metals, can form stable carbides, which are known to exhibit excellent "noble-metal-like" catalytic activities. We demonstrate herein the applications of groups IVB-VIB metals in graphene growth using atmospheric pressure chemical vapor deposition technique. Similar to the extensively studied Cu, Ni, and noble metals, these transition-metal foils facilitate the catalytic growth of single- to few-layer graphene. The most attractive advantage over the existing catalysts is their perfect control of layer thickness and uniformity with highly flexible experimental conditions by in situ converting the dissolved carbons into stable carbides to fully suppress the upward segregation/precipitation effect. The growth performance of graphene on these transition metals can be well explained by the periodic physicochemical properties of elements. Our work has disclosed a new territory of catalysts in the periodic table for graphene growth and is expected to trigger more interest in graphene research.

Controlled growth of high-quality graphene is still the bottleneck of practical applications. The widely used chemical vapour deposition process generally suffers from an uncontrollable carbon precipitation effect that leads to inhomogeneous growth and strong correlation to the growth conditions. Here we report the rational design of a binary metal alloy that effectively suppresses the carbon precipitation process and activates a self-limited growth mechanism for homogeneous monolayer graphene. As demonstrated by an Ni-Mo alloy, the designed binary alloy contains an active catalyst component for carbon source decomposition and graphene growth and a black hole counterpart for trapping the dissolved carbons and forming stable metal carbides. This type of process engineering has been used to grow strictly single-layer graphene with 100% surface coverage and excellent tolerance to variations in growth conditions. With simplicity, scalability and a very large growth window, the presented approach may facilitate graphene research and industrial applications.

High-performance Fe/SiO2 soft magnetic composites (SMCs) by coating pure iron particles with amorphous SiO2 layers have been fabricated by controlled hydrolysation of tetraethyl orthosilicate (TEOS). Microstructural studies show that the pure iron particles are uniformly and entirely coated with the SiO2 insulating layers to form Fe/SiO2 core–shell structure. The dielectric SiO2 layers lead to the electrical insulation behaviour of the SiO2-coated iron particles, which results in low core loss of the compacted Fe/SiO2 SMCs in application of alternating current. The core loss measured at a frequency of 50 Hz and an induction level of 1 T is 3.5 W kg−1, which is much lower than that of the commercial SMCs prepared by coating iron particles with phosphate layers. The Fe/SiO2 SMCs exhibit nearly the same coercivity as that of pure iron, and saturation magnetization of 18.2 kG, a little lower than that of pure iron due to the nonmagnetic SiO2 layers. The low core loss and high saturation magnetization promise the great potential of Fe/SiO2 SMCs in high-power applications. High-frequency measurements reveal that the working frequency of the Fe/SiO2 SMCs can reach up to 20 MHz.

Spherical gold (Au) nanoparticles are formed onto glass surface by sputtering of Au foil and the following annealing process. By employing electric field assisted annealing of above as-prepared samples, the original spherical Au nanoparticles are dissolved to lunar-eclipselike structure and even fully dissolved. When applied voltages are increased in steplike feature, spikelike sharp current increase is observed at every voltage step, and it is followed by a rather long current decaying process. The spikelike current increase indicates the onset of electronic transport, leading to Au nanoparticles polarization and ionization. Long current decaying process is assigned to the electronic conduction from cathode to recombine with as-ionized positive charges, along with Au cationic transport resulting in dissolution of Au atoms from the nanoparticles. Our current study provides straightforward evidence of electric field assisted dissolution of Au nanoparticles on glass surface.

Dissolution of Au rods in gold-doped silicate glass is observed experimentally during the dc electric field thermal poling. Scanning electron microscopy characterizations show that some Au rods with a high aspect ratio are dissolved to spherelike particles and others still keep an elongated structure, which is well accorded with the absorption spectroscopy results. The mechanism for dissolution of Au particles is attributed to electron tunneling conduction and Au cationic conduction, based on electrical measurements during the electric field assisted dissolution process. Electric field thermal poling provides a promising method for the controlling of structural and optical properties of noble metal-doped silicate glass.