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Strain engineering is a popular approach for manipulating material properties through modifying crystal structures and/or electron-lattice interactions. In this work, we used a phase transition material, vanadium dioxide (VO2) as an active and reconfigurable substrate to generate a controllable strain. Amorphous ferromagnetic Ni thin films were deposited on the (010)-VO2/(0001)-Al2O3 substrates. It is observed that the magnetic moments of the Ni thin film were modulated by interfacing it with the VO2 thin film. We observed a hysteresis in the magnetic moment-temperature curves in the vicinity of the metal–insulator transition of the VO2 thin films at a low magnetic field bias (

As one of the most promising Pt alternatives for cost-effective hydrogen production, molybdenum disulfide (MoS2), although has been studied extensively to improve its electrocatalytic activity, suffers from scarce active sites, low conductivity, and lack of interaction with substrates. To this end, we anchor ultradispersed and single-layered MoS2 nanoflakes on graphene sheets via a hybrid intermediate (MoOx-cysteine-graphene oxide), which not only confines the subsequent growth of MoS2 on the graphene surface but also ensures the intimate interaction between Mo species and graphene at the initial stage. Mo-O-C bond and a possible residual MoO3-x layer are proposed to comprise the interface bridging the two inherent incompatible phases, MoS2 and graphene. This strongly coupled structure together with the highly exposed MoS2 morphology accelerates the electron injection from graphene to the active sites of MoS2, and thus the hydrogen evolution reaction (HER) can achieve an overpotential of ∼275 mV at ∼-740 mA cm-2, and a Pt-like Tafel slope of ∼35 mV dec-1. Our results shed light on the indispensable role of interfacial interaction within semiconducting material-nanocarbon composites and provide a new insight into the actual activity of MoS2 toward the HER.

Development of novel electrode materials with unique architectural designs is necessary to attain high power and energy density lithium-ion batteries (LIBs). SnO2, with high theoretical capacity of 1494 mAh g−1, is a promising candidate anode material, which has been explored with various strategies, such as dimensional reduction, morphological modifications and composite formation. Unfortunately, most of the SnO2-based electrodes are prepared by using complex chemical synthesis methods, which are not feasible to scale up for practical applications. In addition, concomitant irrecoverable initial capacity loss and consequently poor initial Coulombic efficiency still persistently plagued these SnO2-based anodes. To overcome hitherto conceived irreversible formation of Li2O by conversion reaction, to fully harness its theoretical capacity, this work demonstrates that a hierarchical structured SnO2-C nanocomposite with 68.5% initial Coulombic efficiency and reversible capacity of 725 mAh g−1 can be derived from the mixtures of SnO2 and graphite, by using low cost industrial compatible high energy ball milling activation.

Heterostructures composed of superconductor and ferroelectrics (SC/FE) are very important for manipulating the superconducting property and applications. However, growth of high-quality superconducting iron chalcogenide films is challenging because of their volatility and FE substrate with rough surface and large lattice mismatch. Here, we report a two-step growth approach to get high-quality FeSe

(K,Na)NbO

Elevated intraocular pressure (IOP) is a well-documented risk factor for glaucoma. Here we describe a novel, effective method for consistently inducing stable IOP elevation in mice that mimics the post-operative complication of using silicone oil (SO) as a tamponade agent in human vitreoretinal surgery. In this protocol, SO is injected into the anterior chamber of the mouse eye to block the pupil and prevent inflow of aqueous humor. The posterior chamber accumulates aqueous humor and this in turn increases the IOP of the posterior segment. A single SO injection produces reliable, sufficient, and stable IOP elevation, which induces significant glaucomatous neurodegeneration. This model is a true replicate of secondary glaucoma in the eye clinic. To further mimic the clinical setting, SO can be removed from the anterior chamber to reopen the drainage pathway and allow inflow of aqueous humor, which is drained through the trabecular meshwork (TM) at the angle of the anterior chamber. Because IOP quickly returns to normal, the model can be used to test the effect of lowering IOP on glaucomatous retinal ganglion cells. This method is straightforward, does not require special equipment or repeat procedures, closely simulates clinical situations, and may be applicable to diverse animal species. However, minor modifications may be required.

Perpendicular magnetic anisotropy is important for increasing the information storage density in the perpendicular magnetic recording media, and for rare-earth-transition-metal alloys with bulk perpendicular magnetic anisotropy that generate great research interest due to their abundant interesting phenomena, such as fast domain wall motion and skyrmion. Here, we deposit amorphous GdFe ferrimagnetic films on Pb(Mg

In this paper, we prepare heavily electron doped $\mathrm{L}{\mathrm{a}}_{0.04}\mathrm{B}{\mathrm{a}}_{0.96}\mathrm{Sn}{\mathrm{O}}_{3}$ (LBSO) thin films on a $\mathrm{SrTi}{\mathrm{O}}_{3}$ (STO) substrate by the pulsed laser deposition method under different oxygen pressures, in which different levels of oxygen vacancy concentrations are present. Normally, oxygen vacancies are implicitly assumed as isolated point defects that dope the materials with electron carriers, whereas oxygen-deficient LBSO films exhibit an apparent metal-to-insulator transition combined with lower carrier concentrations and mobility with increased oxygen vacancies, which are concluded from the transport measurement data. Considering the almost constant density of threading dislocations and the higher formation energies for other intrinsic crystal defects, the observed transport trends are ascribed to the extra oxygen vacancies introduced. Therefore, strong electron localization originating from the interaction between the oxygen vacancy and La impurity is proposed for interpreting the behavior in oxygen-deficient LBSO films. Oxygen-deficient crystal structure models for LBSO have been optimized and the electronic structures are revealed by first-principles calculations based on the density functional theory. The partial density of states results indicate that strong electron localization comes from the deep strongly localized states in the forbidden gap, which are mainly composed of hybridized orbitals of $\mathrm{O}\phantom{\rule{0.16em}{0ex}}2p$ with $\mathrm{Sn}\phantom{\rule{0.16em}{0ex}}5s5p$ and some amount of $\mathrm{Sn}\phantom{\rule{0.16em}{0ex}}4d$. Thus, the control of the oxygen defects and the related electronic states in barium stannate is essential for achieving optimal electrical performance and as potential applications in perovskite heterostructure devices.

The electrochemical oxidation of ethanol results in the formation of strongly adsorbed intermediates. Pt–Rh catalysts are proposed as alternatives since they easy the C[sbnd]C bond breaking. However, the effect of the Pt–Rh structure on the catalytic activity and selectivity to CO 2 is not well understood. Here, we synthesised Pt/C and two different Pt–Rh/C catalyst architectures, an alloy (Pt 3 Rh/C)and a bimetallic mixture (Pt 3 –Rh/C)to study the effect of catalyst structure on its catalytic activity and on the products formed during the ethanol oxidation in acid media. The nanoparticles were prepared by a modified polyol reduction method using ethylene glycol as a co-reducing agent and Pb as a material of sacrifice, to obtain very small and well-dispersed nanoparticles on the carbon support. Fourier transform infrared spectroscopy and derivative voltammetry was used to give insights about the ethanol oxidation mechanism occurring at the developed catalysts. The samples characterised by X-ray diffraction analysis showed distortions in the Pt lattice parameters for the Pt-Rh alloy structure due to the presence of Rh in the catalyst's composition. Transmission electron microscopy analyses indicate that nanoparticles were well-dispersed on a carbon support, with spherical shapes and small particle sizes (2–3 nm). in situ X-ray absorption spectroscopy data evidence that Pt–Rh interactions produce changes in the Pt 5d band vacancy. The electronic effect is maximized when Pt forms an alloy with Rh, resulting in the highest d-band vacancy of the Pt 3 Rh/C. The Pt 3 Rh/C catalyst showed the highest activity towards ethanol oxidation, presenting current densities in a quasi-steady-state condition (measured at 600 mV)around 5.2 times higher than the commercial Pt/C (Alfa Aesar). Moreover, the onset potential for ethanol oxidation shifts to more negative potentials (110 mV lower taken at 1 mA cm –2 )was also observed. In situ FTIR data revealed that Pt/C catalyst favours the formation of acetic acid. The synergistic effect between Rh and the alloy structure results in an easier C[sbnd]C bond breaking for Pt 3 Rh/C, in comparison to Pt 3 –Rh mixture, thus favouring CO 2 formation at lower potentials.

The enigma of the emergent ferromagnetic state in tensile-strained $\mathrm{LaCo}{\mathrm{O}}_{3}$ thin films remains to be explored because of the lack of an agreed-upon explanation. The direct magnetic imaging technique using a low-temperature magnetic force microscope (MFM) is critical to reveal new aspects of the ferromagnetism by investigating the lateral magnetic phase distribution. Here we show the experimental demonstration of the rare halved occupation of the ferromagnetic state in tensile-strained $\mathrm{LaCo}{\mathrm{O}}_{3}$ thin films on $\mathrm{SrTi}{\mathrm{O}}_{3}$ substrates using the MFM. The films have a uniformly strained lattice structure and minimal oxygen vacancies (less than 2%) beyond the measurement limit. It is found that percolated ferromagnetic regions with typical sizes between 100 and 200 nm occupy about 50% of the entire film, even down to the lowest achievable temperature of 4.5 K and up to the largest magnetic field of 13.4 T. Preformed ferromagnetic droplets were still observed when the temperature is 20 K above the Curie temperature, indicating the existence of a possible Griffiths phase. Our study demonstrates a submicron-level phase separation in high-quality $\mathrm{LaCo}{\mathrm{O}}_{3}$ thin films, which has substantial implications in revealing the intrinsic nature of the emergent ferromagnetism.

In article 1900310, Yong Yang and co‐workers present a strategy, the “coupled resonance” effect, matching the excitation wavelength with the molecular resonance, charge transfer (CT) resonance and electromagnetic resonance of the surface‐enhanced raman scattering (SERS) substrate, to optimize the SERS performance of a new semiconductor SERS‐active substrate Ta2O5 by energy band engineering. Furthermore, the concomitant photoinduced degradation of probed molecules in the time‐scale of SERS detection is revealed as a non‐negligible factor that limits the SERS performance of some semiconductors with photocatalytic activity.

Understanding the molecular mechanism of glaucoma and development of neuroprotectants is significantly hindered by the lack of a reliable animal model that accurately recapitulates human glaucoma. Here, we sought to develop a mouse model for the secondary glaucoma that is often observed in humans after silicone oil (SO) blocks the pupil or migrates into the anterior chamber following vitreoretinal surgery. We observed significant intraocular pressure (IOP) elevation after intracameral injection of SO, and that SO removal allows IOP to return quickly to normal. This simple, inducible and reversible mouse ocular hypertension model shows dynamic changes of visual function that correlate with progressive retinal ganglion cell (RGC) loss and axon degeneration. It may be applicable with only minor modifications to a range of animal species in which it will generate stable, robust IOP elevation and significant neurodegeneration that will facilitate selection of neuroprotectants and investigating the pathogenesis of ocular hypertension-induced glaucoma.

The effects of Ca/Si ratio, aluminum and magnesium on the carbonation behavior of calcium silicate hydrate (C-S-H) were investigated by using X-ray powder diffraction (XRD), nuclear magnetic resonance (NMR) and thermogravimetric analyzer (TGA). The results showed that the Ca/Si ratio, Al/Si ratio and Mg/Si ratio had a significant influence on the structure, carbonation products and carbonation resistance of C-(M)-(A)-S-H. The mean chain length of silicate chains in C-S-H increased as the Ca/Si ratio decreased. Aluminum uptake in C-S-H increased the content of bridging silicate tetrahedron (Q2). A cross-linked structure (Q3) appeared when magnesium uptake in C-S-H. The carbonation product of C-S-H was vaterite if the Ca/Si ratio was lower than 0.87. The carbonation products of C-S-H were vaterite and calcite if the Ca/Si ratio was higher than 1.02. C-M-S-H had more polymerized units, stronger bond strength and better carbonation resistance than C-S-H.

The smart release of healing agents is a key factor determining the inhibition efficiency of microcapsules-based corrosion inhibitors for reinforced concrete. In this study, the release behavior of benzotriazole (BTA) in microcapsule-based inhibitors was investigated in mortar sample to clarify the influence of different hydration products on the release process. The results indicated that under high pH environment (pH &gt, 12.4), only about 5% reserved BTA was released from the mortar sample. pH drop resulted in the increased release of BTA from mortar sample. Most BTA in the microcapsule-based inhibitors was released from mortar sample in low pH environment, which was closely related to morphology/composition alterations of hydration products caused by pH drop of the environment. The smart release of BTA dramatically delayed corrosion initiation of reinforced mortar and halted corrosion product accumulation on the steel surface. Therefore, the corrosion resistance of the reinforced mortar was improved after corrosion initiation.

The bifunctional mechanism is well-acknowledged for the promoted CO oxidation on Pt-based bimetallic electrocatalysts. However, the direct identification of the active oxygenated species and the nature and electrochemistry of the second component are still a matter of debate. Herein, Snad-Pt/C catalysts, where Sn ad-atoms are exclusively on the surface of Pt nanoparticles at low coverages ranging from 0.0033 to 0.2 monolayers to avoid sub-surface Sn and alloy formation, were prepared as a model system to resolve these issues using a surface organometallic chemistry approach. Effects of the Sn ad-atoms on CO oxidation were studied by CO stripping voltammograms as a function of Sn coverage. Using in situ XAS measurements, the Sn average oxidation state is estimated to increase from +0.2 to +3.1 as the potential increases from 0 to 0.8 VRHE, with the number of the oxygen neighbours increasing stepwise. Pt4.5-Sn-(OH)1.5 is revealed as the active species responsible for the bifunctional mechanism at low overpotentials and is generated via a redox couple corresponding to Pt4.5-Sn*/Pt4.5-Sn-(OH)1.5.

In alkali-activated slag (AAS), the passive film significantly influences the corrosion behavior of the reinforcing steel. The relationship between the surface characteristics and electrochemical performance of the passive reinforcing steel was investigated in simulated alkali-activated slag pore (SSP) solution in this paper. An adsorption aluminate/silicate layer (60 nm) generated on the reinforcing steel surface. Further, due to the influence of S2−, less compact passive film (containing FeS in the inner film) formed, leading to lower passive film resistance. However, the reinforcement still presented slightly higher charge transfer resistance due to the barrier effect of the adsorption layer in SSP solution.

The superplasticizers with a high-order configuration including star, branched, clawed or corosslinked shape, have exhibited superior fluidity retention effect in cementitious mixes, but are often prepared with tedious routes. This paper employed a facile and proven emulsion polymerization technology to prepare nanomicellar polyacrylate ether superplasticizer (PAE). The precise tri-copolymer structure of PAE of poly(tert-butyl acrylate)–co-polycarboxylate-co-poly(isoprenyl polyethenoxy ether) (PtBA-co-PAA-co-PTPEG) was confirmed by 1H nuclear magnetic resonance (NMR). High-resolution transmission electron microscopy (TEM) verified the core–shell configuration of PAE and further measured colloidal nanomicelles had an average size diameter at 18–35 nm. Based on the special configuration, masses of carboxyl groups were pre-reserved in nanocores via PtBA and encapsulated PAA segments, which would be released into the paste to disperse cement particles over 4 h, during the hydrolysis of PtBA pendent chains and dissociation of nanomicelles. This process was revealed by time-dependent evaluation of spread flow and Zeta potential. Furthermore, the action mechanism of micellar PAE dispersing cement and hydrate by adsorbing onto their surfaces was directly observed by TEM testing. The retardation effect of PAE in Portland cement was evaluated by the delayed hydration heat, lower hydration rate and longer setting time, in comparison with control sample. This work offers a superior fluidity retention superplasticizer for reducing the fluidity loss of cement paste, and demonstrates the fluidity retention mechanism of colloidal PAE via nanomicelle dissociation, carboxyl release, and redispersion in alkaline cement paste.

In situ and operando techniques providing information regarding adsorbate bonding and atomic arrangements on the electrode surface along with pure electrochemical measurements are needed to more fully understand the detailed mechanism of electrocatalytic reactions on high surface areas/nanoparticle electrocatalysts. X-ray adsorption spectroscopy (XAS) is a powerful tool to interrogate the electronic structure and local coordination environment of such electrocatalysts under working conditions, but it should be acknowledged that standard XAS methods are not intrinsically surface sensitive. This review will present recent in situ XAS studies on single-atom, metal, and metal oxide electrocatalysts, highlighting the approaches taken to achieve surface sensitivity by careful designing of the sample under investigation.

The interplay of internal charge and spin degrees of freedom in diluted magnetic semiconductors (DMSs) determines the magnetic, electrical, and optical properties for desired spintronic devices. However, elusive signs in DMSs, such as Curie temperatures far over 300 K, long-range magnetic order at concentrations of magnetic cations of a few percent, temperature-insensitive, and anhysteretic ferromagnetism, challenge our understanding of magnetism in solids. To approach the truth, the magnetism of Mo-doped BaSnO3 was investigated in this work from experiments to density functional theory (DFT) calculations. Electron spin resonance measurements confirm the existence of oxygen vacancies in the samples, and BaMo0.0625Sn0.9375O3−δ, where δ represents the number of oxygen vacancies, displays much weaker ferromagnetism compared to the DFT results without spin–orbit coupling (SOC). Therefore, a small orbital contribution restored in spin–orbit coupling (SOC) was introduced for the partial density of states and band structure calculations. The modified DFT calculations indicate that the increase in oxygen vacancies leads to an obvious reduction of the total density of states (DOS) near Fermi level (EF), lower dispersity of the conduction band, and deep localized states in the bandgap, which help explain the weak ferromagnetism measured in BaMo0.0625Sn0.9375O3−δ containing considerable oxygen vacancies. This study confirms that the contribution of orbital electron states and defects that were ignored in the conventional explanation should be considered to solve the elusive magnetism in diluted magnetic oxides and offers a guide to improve the magnetism.

This work presents a theoretical analysis of optical and electronic properties of uniform and random silver (Ag) and aluminum (Al) nanowire (NW) layers. At low concentrations of NWs the uniform and random layers possess similar average transmittance in the visible spectrum. However, at high concentrations of NWs the random Ag and Al layers demonstrate up to 38% and 45% average transmittance, respectively. Moreover, at high concentrations of NWs the uniform and random Ag layers outperform identical Al layers up to 15% and 5% average transmittance, respectively. Our results indicate that metallic random NW transparent conductive layers benefit in optoelectronic devices demanding lowest sheet resistance, such as solar cells and light-emitting diodes.

The influences of naphthalene-based plasticizers and polycarboxylate acid/salt superplasticisers on creep of concrete, including basic creep and drying creep, were investigated. Internal relative humidity and pore structure of concrete and the surface tension of pore solution were tested. The results show that polycarboxylate acid/salt superplasticizers refine capillary pores in concrete and reduce surface tension of pore solution. In addition, restrain internal moisture transmission and redistribution. As a result, creep of concrete is reduced. Compared with naphthalene-based plasticizer, polycarboxylate acid/salt superplasticizer causes a greater reduction of drying creep, but a smaller reduction of basic creep. This is because the moistures redistribution is quite feeble and quickly balanced in sealed condition. Concrete with polycarboxylate acid/salt superplasticizer has the lowest creep value because polycarboxylate acid/salt superplasticizer improves hydration degree and reduces porosity of macro pores.

Small cracks in concrete may develop into large cracks to decrease service life of concrete structures. It is necessary to restrict the development of early age small cracks promptly. This study presents a bio-restoration method to improve the self-healing effectiveness of the cement-based materials cracks rapidly. Ceramsite carrier was used to immobilize bacteria, while substrate and nutrients mixed evenly were immobilized into other original carrier. The section surface of paste specimens before and after curing was investigated by staining. Water permeation coefficient and flexural strength test were applied to characterize the repairing effectiveness of specimens. Experimental results show that plenty of white precipitation generated on the section surface after curing 21 days and the apparent water permeation coefficient of specimens changed slightly after restoring 28 days. The area repair rate of section surface of the samples with bacteria and nutrients immobilized into ceramsite was run up to 87.5%. The flexural strength of specimens repaired could increase from 56% to 72% than other microbiological methods. SEM/EDS and XRD analysis results show that the precipitation formed in cracks is calcite.

A high working voltage and fast charging/discharging capability are important to a supercapacitor device in order to achieve decent energy densities with high power. In this work, we report 2.0 V quasi-solid-state symmetric capacitive device based on Fe 2 N-Ti 2 N (FTN) core-shell nanorod array electrodes. Through a surface protection by a thin and ultra-stable Ti 2 N shell, Fe 2 N converted from its oxyhydroxide precursor inhibits the original nanorod structure. Due to advantageous features of these core-shell metal nitride electrodes (e.g., high conductivity, structure stability, direct current path), the symmetric device permits ultrahigh scan rates (up to 50 V s −1 ) and delivers fairly stable capacitance in long-term cycles (~82 F g −1 with ~99% capacitance retention in 20,000 cycles). As a result, the supercapacitor exhibits an impressive energy density of ~48.5 W h kg −1 at the power of 2700 W kg −1 . These results demonstrate the potentialities of metal nitride nanorods array for high energy density capacitive device.

Axon injury is an early event in neurodegenerative diseases that often leads to retrograde neuronal cell death and progressive permanent loss of vital neuronal functions. The connection of these two obviously sequential degenerative events, however, is elusive. Deciphering the upstream signals that trigger the neurodegeneration cascades in both neuronal soma and axon would be a key step toward developing the effective neuroprotectants that are greatly needed in the clinic. We showed previously that optic nerve injury-induced neuronal endoplasmic reticulum (ER) stress plays an important role in retinal ganglion cell (RGC) death. Using twoin vivomouse models of optic neuropathies (traumatic optic nerve injury and glaucoma) and adeno-associated virus–mediated RGC-specific gene targeting, we now show that differential manipulation of unfolded protein response pathways in opposite directions—inhibition of eukaryotic translation initiation factor 2α-C/EBP homologous protein and activation of X-box binding protein 1—promotes both RGC axons and somata survival and preserves visual function. Our results indicate that axon injury-induced neuronal ER stress plays an important role in both axon degeneration and neuron soma death. Neuronal ER stress is therefore a promising therapeutic target for glaucoma and potentially other types of neurodegeneration.SIGNIFICANCE STATEMENTNeuron soma and axon degeneration have distinct molecular mechanisms although they are clearly connected after axon injury. We previously demonstrated that axon injury induces neuronal endoplasmic reticulum (ER) stress and that manipulation of ER stress molecules synergistically promotes neuron cell body survival. Here we investigated the possibility that ER stress also plays a role in axon degeneration and whether ER stress modulation preserves neuronal function in neurodegenerative diseases. Our results suggest that neuronal ER stress is a general mechanism of degeneration for both neuronal cell body and axon, and that therapeutic targeting of ER stress produces significant functional recovery.

In this study, the influence of polycarboxylate superplasticizers (PCEs) on durability of concrete was investigated. Carbonation, water impermeability and rapid chloride permeability of concrete with different types of polycarboxylate superplasticizer and polynaphthalene superplasticizer (PNS) were tested. In order to obtain deeper insights into the influence of PCE on concrete durability, microstructure in the concrete was explored by means of mercury intrusion porosimetry (MIP), thermogravimetry (TG) and nano-indentation technique. Smaller carbonation depth, water penetration depth and better resistance to chloride ion penetration show that concretes with PCE have better durability performances than concretes with PNS. MIP results show that the mortars with PCE have lower porosity than that with PNS. The fraction of pores with diameters larger than 100 nm in the mortars with PCE is lower than in the mortar with PNS. According to TG tests, there are more hydration products in the cement pastes with PCE than in the cement pastes with PNS. Nano-indentation tests show a higher ratio of high density C–S–H to low density C–S–H in the cement paste with PCE than in the cement paste with PNS. It can be concluded that PCE leads to denser microstructure in concrete than PNS and, therefore, better durability performances of concrete.

We report that magnetization switching behaviors in multiferroic Ni/SiO 2 /Ti/(011)-PMN-PT hetrostructures with Hall-bar geometry can be easily understood by measuring angle-dependent anisotropic magnetoresistance (MR). The MR along the in-plane [100] and [ 01 1 ¯ ] directions of the Pb(Mg 1/3 Nb 2/3 ) 0.7 Ti 0.3 O 3 (PMN-PT) substrate were −0.175% and 0.165% at 200 Oe, respectively. The coercive field along the in-plane [100] and [ 01 1 ¯ ] directions of the PMN-PT substrate were both increased from 30 Oe at 0 kV/cm to 75 Oe at 4 kV/cm. However, we observed the anisotropic tunability of the AMR in this multiferroic heterostructure. While the AMR with magnetic field H (~200 Oe) parallel to j was 0.165% at the zero electric field and decreased to 0.032% at 4 kV/cm, the AMR with H perpendicular to j increased from −0.174% at the zero electric field to −0.339% at 4 kV/cm. Furthermore, based on angle-dependent AMR measurements using rotating in-plane external magnetic fields, the easy axis was determined to lie along the [ 01 1 ¯ ] direction and was rotated 15° by the 4 kV/cm electric field. Our work provides a facile method to study magnetization switching behaviors in multiferroic heterostructures by measuring angle-dependent AMR.

Manganites (R1−xAxMnO3, R = rare-earth cation and A = alkali or alkaline earth cation) host an immense number of phases and electronic properties, which can be mainly manipulated through conventional structural control such as metallic cations, oxygen concentration, or misfit strain. However, their practical applications are heavily hindered due to the requirement of rigid synthesis conditions and prolonged treatment time. Herein, a subtle hydrogenation of canonical epitaxial La0.3Sr0.7MnO3 films gives rise to a series of structural transformations ranging from the perovskite to the intermediate state and to the brownmillerite one, accompanied by tunable electronic performances from the antiferromagnetic insulating phase to the weak magnetic insulating one. Moreover, the hydrogenated La0.3Sr0.7MnO3−δ films show an ultra-high magnetic temperature (>400 K). The efficient modulations of the crystalline structure and functionalities of manganite oxides using the facile hydrogenation process enable practical applications of high-temperature magnetic insulators in spintronic devices.

Replicating the properties of a bulk oxide in its film counterpart is critical for device applications. In this work, the effects of oxygen pressure and buffer layer on double perovskite Y2NiMnO6 (YNMO) thin films have been studied carefully. The increase in oxygen pressure is found to contribute to the lattice relaxation, reduction of Mn3+ ions, and enhancement of magnetization of YNMO films. The out-of-plane lattice constant of the YNMO film at high oxygen pressure can be tuned to nearly match that of the bulk. Moreover, the insertion of a CaTiO3 buffer layer is beneficial for the oxidization of Mn4+ ions. It affects the spin state of YNMO films significantly, while it has little influence on the lattice structure. With co-action of oxygen pressure and the CaTiO3 buffer layer, the lattice structure, element composition, and magnetization of the obtained YNMO films are almost comparable to those of the bulk.

To mitigate the corrosion of steel bars and the erosion of the matrix in cracked reinforced concrete in a marine environment, a new self-healing agent was developed that can not only chemically bind the invading ions in the cracks, but also accelerate the crack closure. The closure ratio of a crack with an initial width of 400 μm can reach 80% after self-healing for 1 day when the developed CaO-NaAlO2 healing agent was added into the concrete with a dosage of 5% by volume. The value for the references without the self-healing was only about 20%. The fast sealing of cracks can rapidly stop the further ingress of these ions. Moreover, reaction products of self-healing, such as Friedel’s salt, Kuzel’s salt and brucite, were detected, which indicates that Cl−, SO42− and Mg2+ ions invading into the cracks were bound chemically. Therefore, the risk of steel bar corrosion was decreased.

Corrosion inhibitor is widely used to mitigate corrosion damage of reinforced concrete. The objective of this study is to clarify the inhibition effect of organic core–shell corrosion inhibitors (CSCI) on the corrosion performance of the reinforcement in simulated concrete pore solution. The results indicated that the corrosion rate of the reinforcement was significantly reduced by the core–shell corrosion inhibitors. When the concentration of BTA-containing CSCI was higher than 2.27 × 10−3 wt%, the inhibition efficiency was above 93%. The inhibitors were efficiently adsorbed on the reinforcement surface and formed [Fen(BTA)p]m complex, which was beneficial for corrosion protection of the reinforcement.

The accurate measurement of chloride content in concrete is of great importance, because chloride-initiated corrosion of the reinforcement significantly influences the durability of reinforced concrete. This paper summarizes the research status of Ag/AgCl ion-selective electrode (ISE) used for non-destructive chloride detection in concrete. In general, four main topics are reviewed, including preparation of Ag/AgCl-ISE, main factors influencing the potential of Ag/AgCl-ISE, detection limit/potential response of Ag/AgCl-ISE, and novel composites/electrochemical methods based on Ag/AgCl-ISE for chloride detection in concrete. Further, the existing problems and research strategies are also discussed in detail in this present review.

Concrete generally deforms and cracks in a non-uniform manner under drying-induced stress. This study used the lattice fracture model to simulate the drying-induced non-uniform deformations, stresses, and micro-crack propagation in concrete. Experiments were designed to validate the lattice fracture model, wherein the drying-induced non-uniform deformations and micro-crack patterns in concrete were measured using a digital image correlation technique and a fluorescent epoxy impregnation method, respectively. It was found that the simulated non-uniform deformations and micro-crack patterns were close to the experimental observations. The interaction mechanism between drying-induced non-uniform stresses and micro-cracks was analysed based on the validated lattice fracture model. The micro-cracks were found to cause stress concentration both in coarse aggregate and the mortar that covered coarse aggregate, which could lead to high micro-cracking risk as drying continues.

Influence of multiple ions on sulfate attack on concrete was studied by measuring the mass change and elasticity modulus (Erd) change and observing cracks at different scale. X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermo gravimetric analysis (TGA) were used to study the evolution of microstructure of concrete during the process of sulfate attack influenced by multiple ions. Diffusion coefficient and thermodynamic modelling were used to study the interactions between the ions and the concrete. It can be summarized that the cation compound in sulfates has a significant impact on the behaviors and mechanism of the degradation of concrete. The presence of chlorides has a mitigating effect on magnesium sulfate attack and delay the deterioration in the early stage, but promoted the migration of sulfate inside the concrete in the later stage. For coupled attacks by multiple ions, i.e. Cl−, SO42+ and CO32−, the ingress of sulfate and chloride into the concrete was influenced by the interactions between those ions. The calcium carbonate with low solubility precipitates in the pore network and decreases the porosity of concrete. As a result, no obvious deterioration and just a few micro-cracks were found in this study.

Establishing definite correlations between specific defects and physicochemical processes is the prerequisite for applying defect-engineering to optimize material properties. However, systematic investigations are required to fulfill this task. In this work, for the first time, a kind of defect with low electron density is quantitatively demonstrated to be correlative with photocatalysis efficiency by using perovskite oxide Na0.5Bi2.5Ta2O9 nanosheets as the model material, in which the defect was systematically introduced and engineered. More importantly, the correlation is found to be not only valid for photocatalysis in Na0.5Bi2.5Ta2O9, but also is pervasive in various materials and different photochemical processes, though it has been overlooked in previous reports. The defect with low electron density acts as the recombination center for photogenerated carriers, therefore it is detrimental to the photo(electro)chemical performance, and the elimination of this kind of defect will be critical for improving photochemical efficiency.

Diluted magnetic semiconductors (DMSs) have drawn much attention due to their potential in spintronics and magnetoelectronics. Transparent conducting oxides, which are characterized by high carrier density and mobility, may provide a platform to realize room-temperature DMS oxides via the carrier-induced ferromagnetism. However, magnetic properties of DMS oxides are sensitive to their stoichiometry, and the magnetic performance of the same material synthesized by different groups or preparation methods may vary greatly. Therefore, it is important to clarify the relationship between the magnetic property and the lattice structure. Here, we investigate the magnetic property of Ru0.037Ba0.963SnO3 powders calcined in different atmospheres. It is demonstrated that for Ru0.037Ba0.963SnO3, the measured ferromagnetism is much weaker than the calculated one, and the ferromagnetism of the samples calcined in oxygen is stronger than that of the samples calcined in air. Electron spin resonance measurements show the existence of oxygen vacancies in Ru0.037Ba0.963SnO3 powders, and the first-principles calculations confirm that oxygen vacancies will suppress the ferromagnetism. This work offers a guide to synthesize diluted magnetic oxides with the desired magnetic property.

Large animal models of optic nerve injury are essential for translating novel findings into effective therapies due to their similarity to humans in many respects. However, most current tests evaluating the integrity of retinal ganglion cells (RGCs) and optic nerve (ON) are based on rodent animal models. We aimed to evaluate and optimize the in vivo methods to assess RGCs and ON's function and structure in large animals in terms of reproducibility, simplicity and sensitivity. Both goats and rhesus macaques were employed in this study. By using goats, we found anesthesia with isoflurane or xylazine resulted in different effects on reproducibility of flash visual evoked potential (FVEP) and pattern electroretinogram (PERG). FVEP with the large-Ganzfeld stimulator was significantly more stable than that with mini-Ganzfeld stimulator. PERG with simultaneous binocular stimulation, with superior simplicity over separate monocular stimulation, was appliable in goats due to undetectable interocular crosstalk of PERG signals. After ON crush in goats, some FVEP components, PERG, OCT and PLR demonstrated significant changes, in line with the histological study. By using rhesus macaque, we found the implicit time of PVEP, FVEP and PERG were significantly more reproducible than amplitudes, and OCT and PLR demonstrated small intersession variation. In summary, we established an optimized system to evaluate integrity of RGCs and ON in large animals in vivo, facilitating usage of large animal models of optic nerve diseases.

Interfacial charge and strain are two coupling effects in semiconductor/ferroelectric epitaxial heterostructures, which are pivotal for use in tailoring functionalities in devices. In this work, La0.04Ba0.96SnO3/0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 heterostructures with varying film thicknesses were prepared in order to understand both charge and strain's contributions to the electric-field induced resistance change. The relative resistance change to the lattice strain remains almost unchanged in those thicker films, while increases a little bit in those thinner films. This slight increase is related to the substrate constraint near the interface and follows Freund's strain relaxation model during the dynamic strain induced by the piezoelectric switch. A depletion layer model was also established to simulate the electroresistance variation from the interfacial charge effect. The depletion layer involves an equilibrium between capture and release of electrons by the acceptor-like defects near the interface region. The resistance change vs electric field evolves from a butterfly-like shape to a square-like when decreasing the film thickness, due to the joint effect of strain and interfacial polarization screening charge. This study provides an insight into understanding heteroepitaxial coupling and exploring their potential applications in oxide electronic devices.

Magnetic ground state in the two-dimensional (2D) limit is fundamental issue and essential building block for next-generation nano-spintronic devices. Here, we report the observation of antiferromagnetic ordering in 2D MnPSe3 by Raman spectroscopy. Thickness and temperature-dependent Raman spectroscopy confirms the antiferromagnetic ordering in MnPSe3 down to atomically thin layers with trivial thickness-dependent Neel temperature from multiple evidence: the enhanced phonon Raman intensities, significant deviations from the anharmonic contribution of phonon frequencies due to spin-phonon coupling, and the occurrence of one-magnon Raman peak below the Neel temperature. The Raman vibration mode evolution studies reveal that the magnetic ion d-electron transfer is mediated by the nonmagnetic clusters of [P2Se6]4-. Our work motivates the explorations of intriguing spin dynamics in 2D antiferromagnet and promotes the development of novel spintronic devices.

Understanding the molecular mechanism of glaucoma and development of neuroprotectants are significantly hindered by the lack of a reliable animal model that accurately recapitulates human glaucoma. Here we sought to develop a mouse model for the secondary glaucoma that is often observed in humans after silicone oil (SO) blocks the pupil or migrates into the anterior chamber following vitreoretinal surgery. We observed similar intraocular pressure (IOP) elevation after intracameral injection into mouse eyes of SO, and removing the SO allows the IOP level to quickly return to normal. This simple, inducible and reversible mouse model showed dynamic changes of visual function that correlate with progressive RGC loss and axon degeneration. We also used a single AAV vector for the first time to co-express miRNA-based shRNA and a neuroprotective transgene and further validated this model as an effective in vivo means to test neuroprotective therapies by targeting neuronal endoplasmic reticulum stress.

Recent achievements in semiconductor surface‐enhanced Raman scattering (SERS) substrates have greatly expanded the application of SERS technique in various fields. However, exploring novel ultra‐sensitive semiconductor SERS materials is a high‐priority task. Here, a new semiconductor SERS‐active substrate, Ta2O5, is developed and an important strategy, the “coupled resonance” effect, is presented, to optimize the SERS performance of semiconductor materials by energy band engineering. The optimized Mo‐doped Ta2O5 substrate exhibits a remarkable SERS sensitivity with an enhancement factor of 2.2 × 107 and a very low detection limit of 9 × 10−9 m for methyl violet (MV) molecules, demonstrating one of the highest sensitivities among those reported for semiconductor SERS substrates. This remarkable enhancement can be attributed to the synergistic resonance enhancement of three components under 532 nm laser excitation: i) MV molecular resonance, ii) photoinduced charge transfer resonance between MV molecules and Ta2O5 nanorods, and iii) electromagnetic enhancement around the “gap” and “tip” of anisotropic Ta2O5 nanorods. Furthermore, it is discovered that the concomitant photoinduced degradation of the probed molecules in the time‐scale of SERS detection is a non‐negligible factor that limits the SERS performance of semiconductors with photocatalytic activity.

In order to hinder ingress of aggressive ions from sea water via cracks efficiently, it is of great significance to realize rapid self-healing in concrete. In this study, the feasibility to promote self-healing of cracked cement paste in sea water by using triethanolamine (TEA) was investigated. To enlarge the effects of TEA, 0.5–2% (by mass of cement) TEA was added into cement pastes and it was found that TEA can dramatically enhance the self-healing efficiency in sea water conditions. In cement pastes with TEA more than 1% (by the mass of cement), the crack closure ratio can reach 100% at a healing period of 1 d in sea water, 20 times faster than a cement paste without TEA. The permeability of cracked specimen with TEA decreased by about 90% after a healing period of 2 days. At the early stage of self-healing promoted by TEA, large amounts of Mg(OH)2 was formed, accounting for about 70 wt% of the reaction products of self-healing. It is well known that TEA can not chelate with Mg2+ ions. Therefore, the large amounts of Mg(OH)2 leading to complete self-healing of cracks in a short time indicates that the promotion on self-healing by TEA was not mainly caused by the chelating action. Experimental results show that in sea water with the high concentration of Mg2+, the property of TEA to increase its surrounding OH− concentration induces the formation of Mg(OH)2. This is the main mechanism of the promotion on self-healing of cracks by TEA in cement paste in sea water.

The influence of copolymers on the material properties of cement-based materials is closely related to their adsorption and distribution in cement matrix. In this study, the adsorption of organic core-shell corrosion inhibitors based on poly(ethylene oxide)-b-polystyrene (PEO-b-PS) micelles on cement particles and their influence on the early age hydration and workability of cement paste were investigated. The results showed that the micelles rapidly adsorbed on cement particles surface within 40 s. At mesoscale, the micelles distribution was uniform in cement matrix; at microscale they were preferentially adsorbed on positively charged aluminates phases. Due to the efficient adsorption, the particle dissolution and precipitation of hydration products were impeded, leading to the slightly retarded early hydration of C3A; the workability of cement paste was improved, which was attributed to the better dispersion of cement particles associated with the altered surface potential of cement particles and steric hindrance effect provided by the micelles.

The acidification damage in the external anode mortar caused by the anodic reactions significantly influences the efficiency of impressed current cathodic protection for reinforced concrete. In this study, novel lightweight functional aggregates (LFA) were proposed to mitigate the acidification damage in the external anode mortar. The results indicated that LFA maintained the high catalytic activity of the primary anode; furthermore, the acidification damage in the secondary mortar was halted both in the vicinity of the primary anode and at aggregate/mortar matrix interface. The prepared LFA can be potentially applied for the preparation of the external anode mortar for ICCP treatment.

Due to different ion types and concentration in pore solution, the passive film on the steel surface possesses different characteristics in alkali-activated fly ash (AAFA). In this study, the passive film formed in simulated AAFA pore solution was investigated by surface analysis and electrochemical measurements. The passive film possessed bilayer structure with FeOOH-rich outer layer and FeO-rich inner layer in simulated AAFA pore solution. Further, a firmly adsorbed zeolite-like layer (200 nm) formed on the steel surface. The formation of more protective passive film and adsorbed layer resulted in higher corrosion resistance of the reinforcement in simulated AAFS pore solution.