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The Pmmn-MnOCl2 monolayer is a ferromagnetic Dirac semimetal with a high Curie temperature and gapless edge state.

BiCrX3 monolayers are robust intrinsic ferromagnetic semiconductors with high Curie temperatures and large in-plane piezoelectric coefficients.

We employ the molecular design strategy of introducing multiple weak interactions and twisted molecular structure into the same molecular system to synthesize a new AIEgen, which exhibited stimuli-responsive crystalline tricolor fluorescent switching.

The objective of this study was to explore an innovative sustained release technology and design a new microporous resin-based polymer device (RPD) for controlled release of glipizide (GZ). Photocurable resin was applied to prepare the resin layer to control GZ release. The impact of formulation parameters consisting of the type and amount of pore formers and pH modifiers, photocurable curing time as well as the weight of resin layer on GZ release were examined. The GZ-RPD was fabricated applying 24 mg of resin layer with PEG400 (100 % of the resin weight) as pore former and 10 mg of Na

The quantum anomalous Hall (QAH) effect has recently drawn great attention in spintronics with extraordinary property of chiral edge states without dissipation in absence of magnetic field. In M

Accurate prediction of the large-scale channel fading is fundamental to planning and optimization in 5G millimeter-wave cellular networks. The current prediction methods, which are either too computationally expensive or inaccurate, are unsuitable for city-scale cell planning and optimization. This paper presents FadeNet, a convolutional neural-network enabled alternative for predicting large-scale fading with high computation speed and accuracy. By using carefully designed input features and neural-network architecture to capture topographical information, FadeNet accurately predicts the large-scale fading from a base station to each location in its coverage area. Evaluations on realistic data, derived from millimeter-wave cells across multiple cities, suggest that FadeNet can achieve a prediction accuracy of 5.6 decibels in root mean square error. In addition, by leveraging the parallel processing capabilities of a graphics processing unit, FadeNet can reduce the prediction time by $40X-1000X$ in comparison to industry prevalent methods like ray-tracing. Generalizations of FadeNet, that can handle variable topographies and base station heights, and its use for optimal cell site selection are also explored.

The energy crisis and the rise of flexible electronics call for a renewable and flexible energy source due to the inconvenience of the traditional power supply. A triboelectric nanogenerator (TENG)...

Purpose The aim of this study was to explore the effects of an enteral nutrition (EN) feeding protocol in critically ill patients. Methods This was a prospective multi-center before-after study. We compared energy related and prognostic indicators between the control group (pre-implementation stage) and intervention group (post-implementation stage). The primary endpoint was the percentage of patients receiving EN within 7 days after ICU admission. Results 209 patients in the control group and 230 patients in the intervention group were enrolled. The implementation of the EN protocol increased the percentage of target energy reached from day 3 to day 7, and the difference between two groups reached statistical significance in day 6 (P = .01) and day 7 (P = .002). But it had no effects on proportion of patient receiving EN (P = .65) and start time of EN (P = .90). The protocol application might be associated with better hospital survival (89.1% vs 82.8%, P = .055) and reduce the incidence of EN related adverse (P = .004). There was no difference in ICU length of stay, duration of mechanical ventilation and ICU cost. Conclusion The implementation of the enteral feeding protocol is associated with improved energy intake and a decreased incidence of enteral nutrition related adverse events for critically ill patients, but it had no statistically beneficial effects on reducing the hospital mortality rate. Trial registration ClinicalTrials.gov , NCT02976155 . Registered November 29, 2016- Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02976155 .

Two-dimensional (2D) materials with intrinsic ferromagnetism and piezoelectricity have received growing attention due to their potential applications in nanoscale spintronic devices. However, their applications are highly limited by the low Curie temperatures (

Recently, numerous two-dimensional (2D) magnetic materials are predicted with various promising properties, whereas noncollinear antiferromagnetic 2D materials are rarely reported. In this paper, we predicted a stable 2D noncollinear antiferromagnetic triangular lattice T-FeO2. The ground state is [Formula: see text] antiferromagnetic with stronger next nearest neighbor exchange coupling than that of nearest neighbor exchange coupling because of the RKKY interaction. Our Monte Carlo simulations reveal that the magnetic phase transition is from a [Formula: see text] antiferromagnetic state to a stripy state and then to a paramagnetic state with increasing temperature. In addition, by tuning the spin direction from an in plane antiferromagnetic state to a canted weak ferromagnetic state, a nontrivial topological phase transition could be induced. Our investigation about magnetic property and nontrivial topological phase transition is very promising for antiferromagnetic spintronics.

Preparation of organic crystals mainly depends on solution-deposition, sublimation, and melt-deposition techniques. Solid-state growth methods are generally not suitable for organic crystal growth due to the unprocurable mass transfer. Herein, we report two pyridine-substituted fluorenone compounds with extraordinary crystal-growth capacity, and these compounds can directly and quickly form single crystals from their amorphous solid powder by heating under antisolvent-assistance conditions. The novel experimental phenomenon and crystal growth mechanism were investigated in depth. The results indicate that multiple intermolecular hydrogen-bonding sites and planar aromatic structure (prone to π-π interactions) of these molecules dominate the mass transfer during crystal growth by providing enough energy. This discovery enhances our knowledge of solid-state methods for single-crystal growth.

In this paper, we predict that the tetragonal MnSi and MnC0.5Si0.5 monolayers are mechanically stable metallic ferromagnetic materials. The thermal stability of the MnC0.5Si0.5 monolayer is verified by our ab initio molecular dynamics (AIMD) result at 300 K. Both MnSi and MnC0.5Si0.5 monolayers exhibit room temperature half-metallic properties, which is very promising for spintronic applications. Both monolayers exhibit large perpendicular magnetic anisotropy, which is desirable for maintaining magnetic order and for high density storage spintronics. A bilayer of the MnSi nanosheet has obviously enhanced thermal stability and exhibits antiferromagnetic metal properties. The Néel temperature could be effectively manipulated and improved by surface functionalization. In addition, monolayer and bilayer MnSi nanosheets exhibit nodal lines in the reciprocal space, and the nodal lines are robust against spin orbit coupling.

In this paper, we consider the problem of quickly detecting an abrupt change in linear regression models. Specifically, an observer sequentially obtains a sequence of observations, whose underlying linear model changes at an unknown time. Moreover, the pre-change linear model is perfectly known by the observer but the post-change linear model is unknown. The observer aims to design an efficient online algorithm to detect the presence of the change via his sequential observations. Based on different assumptions on the change-point, both non-Bayesian and Bayesian problem formulations are considered. In the non-Bayesian setting, the change-point is modeled as a fixed but unknown constant. Two performance metrics, namely the worst case detection delay and the average run length to false alarm, are adopted to evaluate the performance of detection algorithms. In the Bayesian setting, the change-point is modeled as a geometrically distributed random variable. For this case, the average detection delay and the probability of false alarm are used as performance metrics. We propose a novel algorithm, namely the parallel-sum algorithm, for the purpose of change detection. For both setups, we show that the proposed algorithm has a low computational complexity while still offering a good performance in terms of the performance metrics of the respective setting.

The ongoing poisoning of agricultural products has pushed the security problem to become an important issue. Among them, exceeding the standard rate of pesticide residues is the main factor influencing the quality and security of agricultural products. Moreover, the abuse of pesticides has introduced a large amount of residues in soil and drinking water, which will enter the food chain to the human body, leading to neurological disorders and cancer. Therefore, great efforts have been devoted to developing fluorescent sensors for detecting pesticide in a facile, quickly, sensitive, selective, accurate manner, which exhibit greater advantages than some traditional methods. In this review, we mainly focus on summarizing the non-biological fluorescent probes for organic pesticides detection with the detection limit of micromole to nanomole, including organic functional small molecules, calixarenes and pillararenes, metal organic framework systems, and nanomaterials. Meanwhile, we described the different sensing mechanisms for pesticides detection of these mentioned fluorescent sensors, the detection limit of each pesticide, the application in detecting actual samples, as well as their respective advantages and development prospects associated with present non-biological fluorescent sensors.

In this paper, vanadium carbides VC2 and bi-transition-metal carbides V1/2Mn1/2C2 are predicted to be stable metallic nanosheets showing promising mechanical properties and their Young's moduli are 70.8 N m-1 and 83.7 N m-1, respectively. Ab initio molecular dynamics results showed that both VC2 and V1/2Mn1/2C2 can tolerate temperatures up to 1000 K showing favorable thermal properties. The excellent Li-ion specific energy storage capacity and low diffusion barrier also make them promising candidates as anode materials. In addition, nonmagnetic-ferromagnetic (-ferrimagnetic) transitions in VC2 and V1/2Mn1/2C2 can be tuned easily by oxygen or fluorine passivation.

In this paper, two kinds of two-dimensional manganese boride monolayers, h-MnB2 and t-MnB2, are predicted to be stable metallic nanosheets, which exhibit favorable mechanical and thermal properties. The Young's moduli of h-MnB2 and t-MnB2 are 77.73 N m-1 and 59.59 N m-1, respectively. Ab initio molecular dynamics results show that h-MnB2 and t-MnB2 can sustain up to 500 K and 1000 K, respectively. The magnetic property of h-MnB2 is frustrated antiferromagnetic with a Neel temperature of about 25 K, and the magnetic property of t-MnB2 is collinear antiferromagnetic with a Neel temperature of about 317 K. In addition, the electronic structure of the h-MnB2 monolayer can be tuned by passivation to exhibit Dirac states. h-MnB2 can also self-assemble to form nanotubes, and is thus very promising for application as the anode for Li-ion batteries because of its high capacity (about 875 mA h g-1), low diffusion barrier (about 0.03 eV) and strong stability.

In this paper, we designed a two-dimensional honeycomb monolayer ZrB2C2, which is predicted to be a stable nanosheet and exhibits favorable mechanical and thermal properties. The Young's modulus of ZrB2C2 is 122.3 N m-1, which is about one third of that of graphene. The ab initio molecular dynamics (AIMD) results show that ZrB2C2 can sustain up to 500 K. In addition, ZrB2C2 is semi-metallic and it exhibits twelve Dirac cones in the first Brillouin zone; the six pairs of Dirac cones form compensated electron-hole pockets, and the maximum Fermi velocity is about 6.3 × 105 m s-1, which is about 60% of that of graphene. Compared with other transition metal borides which possess Dirac states, the twelve Dirac cones are all robust under different types of external strains, and the Dirac states could be shifted along the opposite direction crossing the Fermi energy barrier by external strains and the gap of the two Dirac cones could be opened around the Fermi energy level with the effect of spin-orbit coupling.

In this paper, we report an experimental observation of the large anomalous Hall effect (AHE) in a hexagonal ferromagnetic $\mathrm{F}{\mathrm{e}}_{5}\mathrm{S}{\mathrm{n}}_{3}$ single crystal with current along the $b$ axis and a magnetic field normal to the $bc$ plane. The intrinsic contribution of the anomalous Hall conductance ${\ensuremath{\sigma}}_{AH}^{\mathrm{int}}$ was approximately $613\phantom{\rule{0.16em}{0ex}}{\mathrm{\ensuremath{\Omega}}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{\ensuremath{-}1}$, which was more than 3 times the maximum value in the frustrated kagome magnet $\mathrm{F}{\mathrm{e}}_{3}\mathrm{S}{\mathrm{n}}_{2}$ and nearly independent of the temperature over a wide range between 5 and 350 K. The analysis results revealed that the large AHE was dominated by a common, intrinsic term, while the extrinsic contribution, i.e., the skew scattering and side jump, turned out to be small. In addition to the large AHE, it was found that the types of majority carriers changed at approximately 275 and 30 K, consistent with the critical temperatures of the spin reorientation. These findings suggest that the hexagonal ferromagnetic $\mathrm{F}{\mathrm{e}}_{5}\mathrm{S}{\mathrm{n}}_{3}$ single crystal is an excellent candidate to use for the study of the topological features in ferromagnets.

Developing high activity graphene-based materials for oxygen reduction reaction (ORR) catalysts remains a key issue for potential applications in fuel cells. According to the DFT calculation results, the distorted niobium-doped graphene (Nb-G) can process the high oxygen adsorption energy (ΔE) on Nb-G that improves the O2 coverage on surfaces of catalysts. Further we find nitrogen (N) can activate Nb-G with higher ΔE and lower work function than Nb-G, promoting the adsorption of O2 and breakage of O–O bond, in favor of the ORR performance. Before constructing N-activated Nb-G (N-Nb-G) materials with few-layer atomic layers, Nb-self-doped graphene is obtained from the 2D niobium carbide (NbC) only by one step incomplete chlorination reaction created by our group. This structural conversion from 2D NbC to Nb-G is accompanied by in-situ Nb doping which successfully overcomes the serious mismatch of lattices between carbon and transition metal atoms. The obtained N-Nb-G by annealing the mixture of melamine and Nb-G shows much enhanced ORR activity (The half-wave potential is 0.824 V). Undoubtedly, this work adds a family member of carbon-based materials with high ORR catalytic performance.

The kinetics, performance and mechanism of the oxidative degradation of 2,6-dichlorophenol (2,6-DCP) by ferrate(VI) (Fe(VI)) were investigated in this study. The kinetics of oxidation of 2,6-DCP with Fe(VI) were studied as a function of pH (8.23–10.45) and temperature (20.0–33.5 ℃). The reaction follows a second-order rate law with first order in each reactant. The reaction rate constants were found to decrease non-linearly from 265.14 ± 14.10 M−1·s−1 at pH 8.23 to 9.80 ± 0.72 M−1·s−1 at pH 10.45. The individual species-specific second-order rate constants were calculated using pH dependence of species distributions of Fe(VI) (HFeO4- and FeO42-) and 2,6-DCP (2,6-DCP and 2,6-DCP-). The reaction of deprotonated 2,6-DCP with protonated Fe(VI) was found to occur fastest among four parallel reactions between Fe(VI) and 2,6-DCP species. The correlation between temperature and rate constant showed that the activation energy of the reaction was 19.00 ± 1.82 kJ·mol−1. Removal performance depends on pH and molar ratio of Fe(VI) to 2,6-DCP. 2,6-DCP degradation efficiency decreased with increasing pH, which was in accord with pH dependence of the reaction constants. Complete removal of 2,6-DCP by Fe(VI) was achieved at a 6:1 or higher molar ratio. The oxidized products (OPs) of 2,6-DCP were identified using high performance liquid chromatography - mass spectrometry (HPLC-MS) and ion-selective electrode (ISE), and a dechlorination and ring-opening mechanism of 2,6-DCP degradation by Fe(VI) was proposed in detail. The results indicate that it is feasible and highly efficient for 2,6-DCP degraded by Fe(VI) to form nontoxic products.

In this paper, manganese carbide (MnC) and niobium carbide (NbC) are predicted as stable monolayer metallic materials, whose Young's moduli are 50.06 N m-1 and 44.07 N m-1, respectively. The ab initio molecular dynamics (AIMD) results show that both MnC and NbC could hold their structure up to 1000 K, showing favorable thermal properties. These monolayers also show good properties for promising application in Li ion batteries because of their high specific capacities and low diffusion barriers. The MnC monolayer is ferromagnetic and the Curie temperature simulated by the Monte-Carlo method is about 205 K. The electronic band of MnC shows a metal to half-metal transition by passivation of Cl or Br atoms, and the functionalization methods also cause the metallic NbC monolayer to exhibit the quantum spin Hall effect (QSHE). These novel transition metal carbide monolayers hold great promise for 2D spintronic and electronic device applications.

Recently, Dirac states in two dimensional materials have drawn great attention because of its desirable transport properties. In this paper, we predicted a two-dimensional hexagonal CrB2C2, which exhibits stable mechanical and thermal properties. Young's modulus of CrB2C2 is 485.67 N/m, which is comparable with that of graphene. In addition, CrB2C2 is half-metallic, and the ferromagnetic Curie temperature is about 1500 K, which is far above room temperature. A CrB2C2 nanosheet exhibits multiple Dirac states in the spin minority channel and forms compensated electron-hole pockets. The Fermi velocity of two different Dirac states is about 4.18×105 and 3.42×105 m/s. In the electronic band structure, the Dirac state at the K point is weakly gapped by 0.38 meV under a spin orbital interaction, while the other one could be topological nontrivially gapped by 37.4 meV, and the bottom Dirac band exhibits a nonzero Chern number at about 0.25 eV above the Fermi energy.

In this paper, we designed a two-dimensional honeycomb monolayer ZrB

A tremendous amount of research is currently focused on two-dimensional (2D) magnetic semiconductors because of their remarkable physical properties and diverse applications. However, their applications are highly limited by the low Curie temperature (TC). Based on first-principles calculations and Monte Carlo simulations, we demonstrate that 2D InCrTe3 monolayers are ideal candidates for next-generation spintronics applications. We show that 2D InCrTe3 monolayers have thermodynamical and mechanical stability. The magnetic couplings between Cr atoms are strong ferromagnetic (FM) interactions. 2D InCrTe3 monolayers have robust FM semiconducting behavior with a bandgap of ∼0.67 eV, adequate TC (higher than ∼300 K), and a giant out-of-plane magnetic anisotropy energy (MAE) of ∼1.4 meV/Cr. Moreover, the low symmetry C3v point group leads to large in-plane piezoelectric coefficients d11 (larger than 4.8 pm/V) and out-of-plane piezoelectric coefficients d31 (larger than 0.39 pm/V), which are higher than many Janus transition metal dichalcogenides. The theoretical predictions of high TC, large MAE, and piezoelectricity in 2D InCrTe3 monolayers suggest that they have great potential for applications in spintronics, nano-sized sensors, and electromechanics.

Micro-supercapacitors are promising energy storage devices that can complement or even replace lithium-ion batteries in wearable and stretchable microelectronics. However, they often possess a relatively low energy density and limited mechanical stretchability. Here, we report an all-in-one planar micro-supercapacitor arrays (MSCAs) based on hybrid electrodes with ultrathin ZnP nanosheets anchored on 3D laser-induced graphene foams (ZnP@LIG) arranged in island-bridge device architecture. The hybrid electrodes with a large specific surface area demonstrate excellent ionic and electrical conductivities, impressive gravimetric (areal) capacitance of 1425 F g−1 (7.125 F cm−2) at 1 A g−1, and long-term stability. In addition to high energy (245 m Wh cm−2) and power (12.50 mW kg−1 at 145 m Wh cm−2) densities, the MSCAs with excellent cycling stability also showcase adjustable voltage and current outputs through serial and parallel connections of MSC cells in the island-bridge design, which also allows the system to be reversibly stretched up to 100%. Meanwhile, theoretical calculations validated by UV–vis absorption spectra partially suggest that the enhanced capacitance and rate capability may result from the improved electrical conductivity and number of adsorbed charged ions (Na+ in Na2SO4 aqueous electrolyte and K+ in PVA/KCl gel electrolyte) on the pseudocapacitive non-layered ultrathin ZnP nanosheets. The integration of the all-in-one stretchable MSCAs with a crumpled Au-based triboelectric nanogenerator and stretchable crumpled graphene-based strain sensor demonstrates a self-powered stretchable system. The coupled design principle of electronic materials and device architecture provides a promising method to develop high-performance wearable/stretchable energy storage devices and self-powered stretchable systems for future bio-integrated electronics.