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Since the concept of “multiferroic” was first proposed in 1968, the coupling effect between different ferroic orders has attracted great interest in energy, information, and biomedical fields. However, the fully ferroelectric–fully ferroelastic effect has never been experimentally observed in hybrid perovskites, even though this effect was predicted to exist half a century ago. Realizing such cross-linking effects of polarization vectors and strain tensors has always been a huge challenge because of the complex difference in these two ferroic origins. Here, we report a multiferroic with full ferroelectricity and full ferroelasticity in two-dimensional (2D) hybrid perovskites based on ferroelectrochemistry. The dynamic molecular reorientations endow (cyclohexanemethylaminium)2PbCl4with a desired symmetry change of 4̅2mFmm2 at a Curie temperature of 411.8 K. More strikingly, the switchable evolution of ferroelastic domains was directly observed under the control of either electric or mechanical fields, which is the first experimental observation of a fully ferroelectric–fully ferroelastic effect in hybrid perovskites. This work would provide new insights into understanding the intrinsic cross-linking mechanism between ferroelectricity and ferroelasticity toward the development of multichannel interactive microelectronic devices.

The void-free filling of microvia through copper electronic plating in printed circuit board application relies critically on multi-component additives including suppressor, accelerator, and leveler. In this study and for the first time, we have developed a new hypotoxic additive, Polixetonium Chloride (PC), as a single component additive in copper electronic plating. Chronocoulometric measurements and finite element method computations combined with Cu electronic plating indicate that the PC can inhibit copper deposition at the mouth of microvia and improve copper deposition at the bottom of microvia by increasing local current densities. Chronopotentiometric studies and in situ FTIR spectroscopic analysis together with density functional theory calculations illustrate that Cl−behaves the anchor of PC to enhance its adsorption, and the adsorption ability of PC in microvia is gradually weakened from top to bottom, which is in favor of the electrodeposition of cupric ions at the bottom of microvia for void-free filling.

Objective: This study utilized the stimulated thyroglobulin (sTg) to thyroid stimulating hormone (TSH) ratio to predict the long-term efficacy of 131I therapy in patients with moderate-to-high-risk differentiated thyroid cancer (DTC). Methods: This study retrospectively analyzed 960 DTC patients with a median follow-up time of 30 months (6–92 months). The median age was 44 years. All patients underwent total thyroidectomy, lymph node dissection, and at least one 131I therapy. Patients were subjected to a final efficacy evaluation according to American Thyroid Association’s 2015 guidelines. Patients were grouped according to their TSH levels before the initial 131I therapy and the final efficacy evaluation, and factors influencing TSH levels and final efficacy were analyzed. Construction of nomograms using independent risk factors affecting long-term outcomes. The cut-offs of sTg and sTg/TSH ratios were calculated for different long-term outcomes. Progression-free survival (PFS) of patients was analyzed by making Kaplan-Meier survival according to the cut-offs of sTg and sTg/TSH ratio. Results: TSH (mU/L) levels were more concentrated at 60–90 in females (71.5%) and 30–60 in males (39.0%), while patients with younger age, more lymph node metastases, shorter time interval between surgery and the first 131I therapy, and lower dose of levothyroxine sodium taken prior to the first 131I therapy would have higher TSH levels (All P< 0.05).Patients who are male, have primary tumor involvement of the strap muscles, lymph node metastasis, distant metastasis, and higher sTg and sTg/TSH are more likely to have poor long-term outcomes (All P< 0.05).The cut-offs of sTg and sTg/TSH for long-term efficacy were 7.515 and 0.095. STg, sTg/TSH, tumor size, lymph node metastasis, and distant metastasis were shown to be independent risk factors for long-term efficacy. The mean PFSs were longer for patients who had sTg/TSH ≤ 0.095 and/or sTg≤7.515 ug/L. Conclusions: For patients with moderate-to-high-risk DTC, when sTg>7.515 ug/L and/or sTg/TSH > 0.095 before the first 131I therapy, patients are more likely to have a poor long-term efficacy after full 131I therapy. This means that this group of patients may require further surgical treatment or targeted drug therapy after 131I therapy.

Thanks to the technological advances, electric vehicles (EVs) are becoming more and more economically competitive especially when commercial use scenarios are in concern. However, unlike internal combustion engine vehicles, EVs tend to have shorter range when traveling at higher speed, which would undoubtedly impact how commercial EV should be operated, where time efficiency plays an important role to the business. In this study, a new variant of EV routing problem is established, which explicitly considers such “speed-varying range” (SVR) of EVs and en-route partial re-charging. In view of the complexity of the problem, a deep reinforcement learning approach is tailored, leveraging automated entropy regularisation to enhance exploration. Experiment results show that the policies found by the proposed approach outperform the OR-Tools based ones by better coping with the SVR, and exploiting the en-route charging to improve the overall delivery efficiency.

Ag nanopaste is one of the most promising die-attach materials in power devices. In this work, robust sintered SiC devices are achieved by using graphene reinforced Ag nanopaste to improve the heat dissipation and shear strength. Microstructure, mechanical, and electrical properties of the sintered joints are investigated. The addition graphene can bring exciting performance improvements, and graphene (< 0.25 wt%) is found to be enough to bridge voids among Ag particles. The decomposition temperature of nanopaste exhibits an increasing trend with the increase of graphene content. The sintered layer forms metallurgical interfaces between chip and substrate, while excellent metallurgical combination ensures the mechanical, electrical, and thermal properties of die attachments. The joint strength is significantly improved after adding graphene compared with pristine Ag nanopaste, especially when sintered at a lower temperature of 230 °C, the joint strength is increased by 3~4 times. Good interconnection can be achieved at a sintering temperature of 190 °C. Low temperature interconnection, fast sintering (sintering time: $\ge 1$ min), and lower thermal resistance and junction temperature will provide an effective way to enhance the quality of the sintered Ag joints, which is promising for the attachment of power devices in new energy vehicles.

The large specific surface area of Cu foam was used to manufacture the high-quality of graphene without crystal defects, and the graphene-reinforced Cu foam (G-Cu) was introduced as an interlayer to join C/C composites and titanium alloy. The foam net structure enabled the molten filler to flow into its pores, reduced the aggregation of Ag-based solid solution, promoted the uniform, and dispersed distribution of various phases. Results showed that the joint shear strength with G-Cu foam interlayer reached 50 MPa, which was twice about directly brazed joint. Due to the isolation and protection of the graphene film, the three-dimensional skeleton structure of foam kept intact, and the ability to relieve residual stress was more fully utilized, thereby further improving the brazed joint strength.

Androgen deprivation therapy is administered to suppress the growth of prostate cancer (PCa). However, some cells continue to proliferate independent of hormones, leading to the development of castration-resistant prostate cancer (CRPC). Overexpression of the epidermal growth factor receptor (EGFR) has been observed in CRPC and is associated with an unfavorable prognosis. Gefitinib (GEF) is an EGFR inhibitor used to treat patients with CRPC. Nevertheless, some clinical studies have reported that gefitinib does not result in prostate-specific antigen (PSA) or objectively measurable CRPC reactions. This lack of response may be attributed to the limited solubility in water, high side effects, low tumor aggregation, and insufficient tumor-specific reactions of GEF. In order to tackle these obstacles, we present a practical and efficient approach to administer GEF, encompassing the utilization of biocompatible nanostructures as a vehicle for drug delivery to augment its bioaccessibility and curative potency. Despite their small particle size, poly(d,l-lactide-co-glycolide) acid nanoparticles (PLGA NPs) exhibit a high drug-loading capacity, low toxicity, biocompatibility, biodegradability, and minimal immunogenicity. The drug delivery efficiency can be improved by employing GEF@PLGA NPs, which could also enhance drug cytotoxicity and impede the advancement of prostate cancer. Moreover, through experiments in vivo, it has been verified that GEF@PLGA NPs exhibit selective accumulation in the tumor and effectively restrain tumor growth. Therefore, the GEF@PLGA NPs hold great promise for the treatment of PCa.

Preclinical and clinical studies have demonstrated the synergistic effect of microtubule-targeting agents in combination with Janus kinase 2 (JAK2) inhibitors, prompting the development of single agents with enhanced therapeutic efficacy by dually inhibiting tubulin polymerization and JAK2. Herein, we designed and synthesized a series of substituted 2-amino[1,2,4]triazolopyrimidines and related heterocycles as dual inhibitors for tubulin polymerization and JAK2. Most of these compounds exhibited potent antiproliferative activity against the selected cancer cells, with compound 7gbeing the most active. This compound effectively inhibits both tubulin assembly and JAK2 activity. Furthermore, phosphorylated compound 7g(i.e., compound 7g–P) could efficiently convert to compound 7gin vivo. Compound 7g, whether it was administered directly or in the form of a phosphorylated prodrug (i.e., compound 7g–P), significantly inhibited the growth of A549 xenografts in nude mice. The present findings strongly suggest that compound 7grepresents a promising chemotherapeutic agent with high antitumor efficacy.

Supported cobalt catalysts (Co@C-ZnZrO2and Co/ZnZrO2) were prepared through a metal-organic frameworks (MOFs)-mediated synthesis strategy. The influence of MOFs pyrolysis on the structure and Fischer-Tropsch synthesis performance of supported cobalt catalysts was investigated. The crystalline phase and microstructure of supported cobalt catalysts were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), N2adsorption-desorption and X-ray photoelectron spectroscopy (XPS). The Co/ZnZrO2showed the CO conversion of 18.1% and the C5+selectivity of 77.4%, whereas the Co@C-ZnZrO2exhibited the CO conversion of 8.5% and the C5+selectivity of 35.2%. The excellent CO conversion for Co/ZnZrO2was attributed to the more exposure of active Co sites. Meanwhile, the activity of Co sites on Co@C-ZnZrO2catalyst was restricted by the carbon layer, suppressing the adsorption and activation of syngas on Co sites.

Ferroelastics, the mechanism analogous to ferroelectrics and ferromagnets, have attracted comprehensive attention owing to the prominent spontaneous strain characteristics. However, the contingency of symmetry changes during the phase transition brings a great challenge to the construction of ferroelastic materials. Currently, most of the ferroelastics are accompanied by various physical properties, such as, photoluminescence and thermochromism. There are few reports of ferroelastics with a photochromic effect. Here, we have successfully designed two hybrid metal halide materials, (pyrrolidinium)PbBr3(M-1) and (3-hydroxypyrrolidinium)4Pb3Br10(M-2), both of which possess a two-step dielectric response. The organic-inorganic hybrid materials with structural adjustability provide a good design platform and great possibilities. Meanwhile, the strategy of introducing intermolecular H-bonds increases the phase transition temperature by about 90 K, and also achieves dimensional regulation (3D→2D). Exhilaratingly, the second phase transition of M-2 belongs to the 2/mF1¯-type ferroelastic phase transition according to the Aizu rules, and the ferroelastic domains are observed by a polarizing microscope, which strongly proves the ferroelasticity. Furthermore, we find that these compounds possess a photochromic effect. Especially, the photochromic phenomenon (from milky white to beige) of M-2 is more fascinating, making it a potential candidate for sensors and display devices. The key properties are well-verified through theoretical calculations with high consistency. In short, this photochromic ferroelastic might be a potential candidate in the fields of mechanical switches, shape memory and energy conversion.

Hybrid lead halide perovskites have received extensive scientific attention owing to their great potential in the field of fluorescent displays and light-emitting diodes. Currently, most luminescent materials contain functional molecular and rare-earth metal ion parts. However, the mechanism of photoluminescence property in two-dimensional hybrid lead halide perovskites with different layered inorganic skeletons has been reported rarely. To better understand the effect of an inorganic skeleton on the fluorescence property, here, we report three organic–inorganic hybrid materials with different layered inorganic frameworks: (MACH)2·PbBr4(Prv-1, MACH = cyclohexylmethylammonium), (2-MPQ)·PbBr4(Prv-2, 2-MPQ = 2-methylpiperazinium), and (TMBA)4·Pb3Br10(Prv-3, TMBA = N′N′N′-trimethylbenzylammonium). Among them, Prv-1 is a (100)-oriented perovskite, Prv-2 belongs to the (110)-oriented perovskite, and the inorganic framework of Prv-3 possesses [Pb3Br10] units. Interestingly, Prv-1 has a strong blue-violet fluorescence emission, while the luminescence effect of Prv-2 is very weak; notably, Prv-3 emits a charming bright-orange light. Meanwhile, results of theoretical computational studies also reveal that the electronic structure of all three compounds is highly dependent on structurally distorted [PbBr6] octahedra, and the frontier molecular orbital (FMO) analysis further suggests that HOMO and LUMO of Prv-3 are contributed by inorganic and organic components, respectively. In addition, all three materials belong to direct band gap semiconductors, and the band gaps are 2.79, 2.97, and 2.76 eV, respectively. Significantly, there are obvious differences in conduction bands. Based on the above analysis, the photoluminescence mechanism of three hybrid materials is explained from the electronic levels. Consequentially, this work might provide practical strategies and perspectives for exploring novel structure-related properties.

Selenium (Se) is a micronutrient necessary in small amounts for the proper organism functioning. Se-rich agriculture, also known as special agriculture, has the potential to improve agricultural production and produce beneficial agricultural products. This review discusses the various applications of Se in agriculture, including animal husbandry, crop production and aquaculture. It covers Se metabolites, the function and regulation of selenogenomes and selenoproteomes of human and animal food and the recycling of Se in food systems and ecosystems. Finally, the review identifies research needs that will support the basic science and practical applications of dietary Se in modern agriculture. Selenium is one of the essential micronutrient for humans and animals, and plays an important role in the body. The Selenium content of foods and feeds ultimately depends on the Se content of soils and the capacity of plants to obtain the element from soils.

The phase equilibria of the Cu—Nb—Si system were investigated via a combination of key equilibrated alloys, thermodynamic modeling and first-principles calculations. Sixteen ternary alloys were prepared to determine the isothermal sections at 600 and 700 °C, by means of X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM−EDS). The three- and two-phase regions were determined. The existence of ternary compound τ1(Cu4Nb5Si4) was confirmed. The solubilities of Cu in the NbSi2and Nb5Si3phases were measured. Based on the experimental equilibria data from the literature and the present work, a thermodynamic description of the Cu—Nb—Si system was carried out by using the calculation of phase diagrams (CALPHAD) method supported by first-principles calculations. The substitutional model and sublattice model were employed to describe the solution phases and intermediate phases, respectively. A set of self-consistent thermodynamic parameters of the Cu—Nb—Si system were conclusively obtained. Most of the reliable experimental data were reproduced by the present thermodynamic modeling.

Wildfires in transmission line passages are a severe threat to power security. Two wildfire detection models, which are based on the YOLOv5, are proposed in this paper. Due to the limited computing power of embedded terminals, the proposed models simplify the network structure of YOLOv5. Specifically, one is that only the overall structure of the neck and head parts in the original network structure is simplified, and the second method is based on the first method to delete the modules of backbone, which greatly reduces the number of parameters of the model. The experimental results show that the proposed lightweight models can achieve real-time monitoring in embedded devices while the accuracy and recall remain high.

Compared with the T-cell potential of particulate matter (PM) in animal studies, comprehensive evaluation on the impairments of T-cell response and exposure–response from PM and its components in human population is limited. There were 768 participants in this study. We measured environmental PM and its polycyclic aromatic hydrocarbons (PAHs) and metals and urinary metabolite levels of PAHs and metals among population. T lymphocyte and its subpopulation (CD4+T cells and CD8+T cells) and the expressions of T-bet, GATA3, RORγt, and FoxP3were measured. We explored the exposure–response of PM compositions by principal component analysis and mode of action by mediation analysis. There was a significant decreasing trend for T lymphocytes and the levels of T-betand GATA3with increased PM levels. Generally, there was a negative correlation between PM, urinary 1-hydroxypyrene, urinary metals, and the levels of T-betand GATA3expression. Additionally, CD4+T lymphocytes were found to mediate the associations of PM2.5with T-betexpression. PM and its bound PAHs and metals could induce immune impairments by altering the T lymphocytes and genes of T-betand GATA3.

A kind of interface between power chip and heat sink with high interfacial strength and high thermal conductivity was sintered by different Ag particles in this article. The results showed that the maximum shear strength of the sintered chip joint was 49 MPa and more than the value required by the MIL-STD-883J standard. With the increasing of sintering temperature and pressure, the room temperature thermal conductivity of the Ag sintered layer increased to 265.52 $\text{W}\cdot \text{m}^{-1}\cdot \text{K}^{-1}$ under the combined effects of twin, grain size, porosity, and dislocation density. The thermal conductivity of Ag sintering layer was four times that of tin-lead sintering layer and eight times that of Au-based bonding layer. Meanwhile, the Ag sintered layer had favorable heat dissipation performance at different operating temperatures, which had the potential to be used as the connection interface between power chip and heat sink.

Silicon carbide (SiC) has excellent characteristics such as high thermal and electrical conductivity. However, traditional bonding materials are difficult to serve lastingly at high temperatures, which directly affects the performance of SiC-based devices. In this study, nano foam sheet was prepared by dealloying, and used to sinter chip and substrate at low temperature. Microstructure, interfacial composition, mechanical properties, and fracture of the sintered joint were characterized and analyzed. The precursor was AgCu alloy, and the bicontinuous ligament/channel structure was formed on the precursor surface after dealloying. As the etching temperature increased from 80 °C to 90 °C, the ligament width of nano foam became large and the channel diameter became small. With the extension of the etching time from 2 to 5 h, the etching depth gradually increased. The nano foam sheet could realize a metallurgical reaction between substrate and chip at a sintering temperature of 300 °C. The joint had high shear strength and could meet the strength requirement of the standard.

An adaptive command filter control strategy was proposed to realize the asymptotic tracking of the roll speed, which successfully suppressed torsional vibration for the main drive system of the rolling mill with nonlinear friction, nonlinear damping, current harmonic, time-varying stiffness and unknown disturbance. A finite time predetermined performance method was proposed, so that the speed tracking error of the main transmission system was always constrained in the performance function and converged to its minimum boundary within the specified time. Based on the adaptive estimation of harmonic amplitude, the torque control law of the motor was obtained by using the filter backstepping method, which prevented the torsional vibration of the system caused by the input fluctuation and avoided the complexity explosion of the controller design, and the stability of the closed-loop system was strictly proved by the Lyapunov theory. The actual numerical simulation verified the effectiveness of the proposed control strategy.

A robust torsional vibration suppression strategy is proposed for the main drive system of the rolling mill subject to uncertainties, disturbances and input saturation. With given model information incorporated into observer design, an extended state observer that relies only on roller speed measurements is developed to estimate the system states and lumped uncertainties of the rolling mill main drive system. To handle the motor torque saturation, an auxiliary signal system with the same order as the plant is constructed. The error between the control input and plant input is taken as the input of the constructed auxiliary system, and a number of signals are generated to compensate for the effect of the motor torque saturation. Furthermore, a robust output feedback controller is introduced to obtain better transient and steady-state performance of the rolling mill main drive system and the stability of the closed-loop system is strictly proved via Lyapunov theory. Finally, comparative simulations are performed to verify the effectiveness and superiority of the proposed control strategy.

Broiler chicks are fast-growing and susceptible to dietary selenium (Se) deficiency. This study sought to reveal the underlying mechanisms of how Se deficiency induces key organ dysfunctions in broilers. Day-old male chicks (n=6 cages/diet, 6 chicks/cage) were fed with a Se-deficient diet (Se-Def, 0.047 mg Se/kg) or the Se-Def+0.3 mg Se/kg (Control, 0.345 mg Se/kg) for 6 weeks. The serum, liver, pancreas, spleen, heart, and pectoral muscle of the broilers were collected at week 6 to assay for Se concentration, histopathology, serum metabolome, and tissue transcriptome. Compared with the Control group, Se deficiency induced growth retardation and histopathological lesions and reduced Se concentration in the five organs. Integrated transcriptomics and metabolomics analysis revealed that dysregulation of immune and redox homeostasis related biological processes and pathways contributed to Se deficiency-induced multiple tissue damage in the broilers. Meanwhile, four metabolites in the serum, daidzein, epinephrine, L-aspartic acid and 5-hydroxyindoleacetic acid, interacted with differentially expressed genes with antioxidative effects and immunity among all the five organs, which contributed to the metabolic diseases induced by Se deficiency. Overall, this study systematically elucidated the underlying molecular mechanisms in the pathogenesis of Se deficiency-related diseases, which provides a better understanding of the significance of Se-mediated heath in animals.

This work investigates the synchronization problem of a dynamical network composed of nonlinear nodes with directed couplings and suffering from heterogeneous delays. Specifically, a time-varying pinning control is adopted to achieve synchronization. The system’s dynamics are interpreted under a multiplex network framework, from which an indicator is designed to measure the synchronizability of the pinned network. Criteria are then derived to ensure exponential synchronization while the largest admissible coupling delay is also estimated. These criteria are based on the time average of the proposed indicator over some user-defined time intervals. Therefore, it possesses high versatility to support a wide range of scenarios with different intermittent control strategies. An interesting observation is that the proposed indicator is always upper bounded, manifesting that if the couplings between the nodes are too weak, pinning synchronization may fail no matter how large the pinning gain is. To further demonstrate the applicability of the theorem and the corollaries, numerical examples under different pinning configurations are presented. [ABSTRACT FROM AUTHOR]

Layered 2D organic–inorganic halide perovskites have attracted comprehensive scientific attention due to their excellent dielectric, ferroelectric, and photophysical properties. However, most of the reported crystal compounds only possess a single performance. Here, we report two new layered 2D organic–inorganic halide perovskites: [BA-PbBr4] (Prv-1) and [MACH-PbI4] (Prv-2) (BA = 1-butylamine, MACH = cyclohexanemethylamine). Both compounds (with crystal structures) show switchable phase transitions at 390 and 350 K, respectively. Shockingly, [MACH-PbI4] reveals a high photoluminescence quantum yield of up to 16.3% with the replacement of the halogen and organic cation (Br → I, BA → MACH). In addition, the experimental data and calculated results suggest that both compounds could be used as band gap semiconductors. In brief, this work might provide new strategies for the exploration of dielectric and ferroelectric functional materials.

This paper considers the time difference of arrival (TDOA) and frequency difference of arrival (FDOA) estimation problem for joint localization using unmanned aerial vehicles (UAVs), involving range migration (RM) and Doppler ambiguity within observation interval. A robust estimation method based on interpolation and resampling is proposed. Specifically, the interpolation artificially increases the pulse repetition frequency (PRF). After that, the resampling eliminates the coupling between range frequency and slow time. Finally, a coherent integration step based on inverse discrete Fourier transform (IDFT) is used to achieve parameter estimation and suppress the grating lobes caused by interpolation. The proposed method could be efficiently implemented by fast Fourier transform (FFT), inverse FFT (IFFT) and non-uniform FFT (NUFFT) without parameter searching procedures. Numerical experiments indicate that the proposed method has nearly optimal anti-noise performance but much lower computational complexity than the maximum likelihood estimator, which makes it more competitive in practical applications.

Purpose: This study aimed to develop a clinically predictive nomogram model to predict the survival probability of differentiated thyroid carcinoma patients and compare the value of this model with that of the eighth edition AJCC cancer staging system. Methods: We selected 59,876 differentiated thyroid carcinoma patients diagnosed between 2004 and 2015 from the SEER database and separated those patients into a training set (70%) and a validation set (30%) randomly. We used Cox regression analysis to build the nomogram model (model 1) and the eighth edition AJCC cancer staging model (model 2). Then we compared the predictive accuracy, discrimination, and clinical usage of both models by calculating AUC (Area under the curve), C-index, as well as analyzing DCA (Decision Curve Analysis) performance respectively. Results: AUCs of all predicted time points (12-month, 36-month, 60-month, and 120-month) of model 1 were 0.933, 0.913, 0.879, and 0.868 for the training set; 0.933, 0.926, 0.916, and 0.894 for the validation set. As for model 2, data were 0.938, 0.906, 0.866, and 0.847 for the training set; 0.924, 0.925, 0.912, and 0.867 for the validation set. C-indices of model 1 were higher than those of model 2 (0.923 vs. 0.918 for the training set, 0.938 vs. 0.930 for the validation set). DCA comparison showed that the net benefit of model 1 was bigger when comparing with that of model 2. Conclusions: Model 1 provided with both better predictive accuracy and clinical usage compared with those of model 2 and might be able to predict the survival probability of differentiated thyroid carcinoma patients visually and accurately with a higher net benefit.

Solid/liquid interfacial structure occupies great importance in chemistry, biology, and materials. In this paper, by combining EC-SERS study and DFT calculation, we reveal the adsorption and dimerization of sulfite (SO32–) at a gold electrode/water solution interface, and establish an adsorption displacement strategy to suppress the dimerization of sulfite. At the gold electrode/sodium sulfite solution interface, at least two layers of SO32–anions are adsorbed on the electrode surface. As the applied potential shifts negatively, the adsorption strength of the first SO32–layer is weakened gradually and then is dimerized with the second orientated SO32–layer to form S2O52–, and S2O52–is further reduced to S2O32–. After hydroxyethylene disphosphonic acid (HEDP) is introduced to the gold electrode/sodium sulfite solution interface, the second oriented SO32–layer is replaced by a HEDP coadsorption layer. This results in the first layer of SO32–being desorbed directly without any structural transformation or chemical reaction as the potential shifts negatively. The suppression of sulfite dimerization by HEDP is more clear at the gold electrode/gold sulfite solution interface owing to the electroreduction of gold ions. Furthermore, the electrochemical studies and electrodeposition experiments show that as the sulfite dimerization reaction is suppressed, the electroreduction of gold ions is accelerated, and the deposited gold coating is bright and dense with finer grains.

The relationship between microstructure and corrosion behavior of high-grade pipeline steel under low-temperature conditions was comparatively investigated by the potentiodynamic polarization and electrochemical impedance spectroscopy test combining with optical micrographs, scanning electron microscopy, transmission electron microscopy and electron back-scattered diffraction. The results showed that, compared with room and high temperature, low temperature could influence the corrosion behavior of high-grade pipeline steel, which means that the corrosion potential and current density decreased and the corrosion resistance increased significantly. Moreover, double layer structures of the interface became thicker and more compact. Under low-temperature environment, acicular ferrite had the martensite/austenite constituents with less amount and smaller size, a higher density of low angle grain boundaries and smaller effective grain sizes compared with granular bainite, which demonstrated higher corrosion resistance.

This brief investigates the master–slave synchronization problem of delayed neural networks with general time-varying control. Assuming a linear feedback controller with time-varying control gain, the synchronization problem is recast into the stability problem of a delayed system with a time-varying coefficient. The main theorem is established in terms of the time average of the control gain by using the Lyapunov–Razumikhin theorem. Moreover, the proposed framework encompasses some general intermittent control schemes, such as the switched control gain with external disturbance and intermittent control with pulse-modulated gain function, while some useful corollaries are consequently deduced. Interestingly, our theorem also provides a solution for regaining stability under control failure. The validity of the theorem and corollaries is further demonstrated with numerical examples. [ABSTRACT FROM AUTHOR]

Borylated aza-arenes are of great importance in the area of organic synthesis. A radical borylative cyclization of isocyanoarenes with N-heterocyclic carbene borane (NHC-BH3) under metal-free conditions was developed. The reaction allows the efficient assembly of several types of borylated aza-arenes (phenanthridines, benzothiazoles, etc.), which are difficult to access using alternative methods. Mild reaction conditions, a good functional-group tolerance, and generally good efficiencies were observed. The utility of these products is demonstrated, and the mechanism is discussed.

A novel cascade Cp*Rh(III)-catalyzed C–H alkylation/Cu(II)-promoted α-oxygenation which enabled a three-component carboxygenation of activated alkene is reported. Mild reaction conditions, broad substrate scope, and good functional group tolerance were observed. The synthetic utility of the protocol was showcased by the facile transformations of the product to a variety of structurally diverse molecules. Preliminary mechanistic studies were conducted.

The application of nanotechnologies in formulation has significantly promoted the development of modern medical and pharmacological science, especially for nanoparticle-based drug delivery, bioimaging, and theranostics. The advancement of engineering particle design and fabrication is largely supported by a better understanding of how their apparent characteristics (e.g., size and size distribution, surface morphology, colloidal stability, chemical composition) influence their in vivo biological performance, which raises an urgent need for practical nanoformulation methods. Based on turbulent flow mixing and the self-assembly of molecules in fluids, flash technologies emerged as effective bottom-up fabrication strategies for effective nanoformulation. Among the flash technology family, flash nanocomplexation (FNC) is considered a novel and promising candidate that can promote and optimize formulation processes in a precise spatiotemporal manner, thus obtaining excellent fabrication efficiency, reproducibility and expandability. This review presents an overview of recent advances in fabricating drug-delivery nanoparticles using FNC platforms. Firstly, brief introductions to the basic principles of FNC technology were carried out, followed by descriptions of turbulent microvolume mixers that have significantly promoted the efficiency of FNC-based fabrications. Applications of real formulation cases were then categorized according to the self-assembly-driven interactions (including electrostatic interaction, coordination interaction, hydrogen bonding and hydrophobic interaction) and discussed to reveal the progressiveness of fabricating nanoparticles and discuss how its flexibility will provide advances and replenish the philosophy of nanomedicine formulation. In the end, the commercial potential, current limitations, and prospects of FNC technology for nanoformulation will be summarized and discussed.

Ag–Cu bimetallic nanoparticles, combining the advantages of both Ag and Cu, are a promising material for power electronic packaging. In this work, a supersaturated Ag–7.3 wt % Cu alloy nanoparticle film was developed by using pulsed laser deposition. Unlike Cu nanoparticles, the supersaturated Ag–Cu alloy nanoparticles can conduct bonding in air without the assistance of a reduction agent. The shear strength was >20 MPa when the bonding temperature reached 300 °C, which was above the die shear standard (MIL-STD-883 K, 7.8 MPa) and compatible with the typical die attach process. The Cu separating behavior was accompanied by the bonding process at 250–400 °C, which was discussed systematically. Neck formation was delayed to about 250 °C because of the hindering effect of the thin oxide shell of the Ag–Cu alloy. The necking networks provide volume diffusion paths despite the growth of surface oxide, resulting in compact densification. The bondline under the SiC die consisted of a porous Ag–Cu alloy matrix with a dispersed secondary phase of Cu2O/CuO, which is supposed to have improved electrochemical migration resistance.

The performance optimization of materials is an eternal theme and challenge in scientific research, which is reflected in ferroelectric filed to two hot topics of enhancing Curie temperature (TC) and functional versatility. The former one vitally determines ferroelectric operational temperature range while the latter would open up new application possibilities. Effective chemical modification or doping strategies on A-site and X-site components have been successfully developed in hybrid organic-inorganic perovskite (HOIP) ferroelectrics, however, the important role of adjusting B-site ions has long been overlooked. Here, we have implemented regulation on the ion radius of the B-site component to successfully obtain two new HOIP ferroelectrics (3-pyrrolinium)BBr3(B = Mn and Ni). Compared to parent (3-pyrrolinium)CdBr3, the TC(ΔT = 99 K) was significantly optimized by replacing the Cd2+with smaller Mn2+or Ni2+ions. More strikingly, the introduction of Mn2+and Ni2+ions with octahedral coordination bring out intriguing red emission and magnetism respectively, making the multifunctional integration in a single material for multiple uses. This work provides a feasible strategy for performance optimizing of HOIP ferroelectrics, and would shed light for constructing multifunctional ferroelectrics.

Optoelectronic synapses integrating synaptic and optical-sensing functions exhibit large advantages in neuromorphic computing for visual information processing and complex learning, recognition, and memory in an energy-efficient way. However, electric stimulation is still essential for existing optoelectronic synapses to realize bidirectional weight-updating, restricting the processing speed, bandwidth, and integration density of the devices. Herein, a two-terminal optical synapse based on a wafer-scale pyrenyl graphdiyne/graphene/PbS quantum dot heterostructure is proposed that can emulate both the excitatory and inhibitory synaptic behaviors in an optical pathway. The simple device architecture and low-dimensional features of the heterostructure endow the optical synapse with robust flexibility for wearable electronics. This optical synapse features a linear and symmetric conductance-update trajectory with numerous conductance states and low noise, which facilitates the demonstration of accurate and effective pattern recognition with a strong fault-tolerant capability even at bending states. A series of logic functions and associative learning capabilities have been demonstrated by the optical synapses in optical pathways, significantly enhancing the information processing capability for neuromorphic computing. Moreover, an integrated visible information sensing memory processing system based on the optical synapse array is constructed to perform real-time detection, in situimage memorization, and distinction tasks. This work is an important step toward the development of optogenetics-inspired neuromorphic computing and adaptive parallel processing networks for wearable electronics.

For the first time, we present an original sensing strategy with an ultra-wide detection window from 17 nM to 20 mM to detect SCN−ions. Initially, we investigated the clustering and optical properties of noble metal sol nanoparticles (NPs) due to the competitive interaction of thiocyanate ions (SCN−) and cetyltrimethylammonium bromide (CTAB) under weak acidic conditions, and found that different dimensions and scales of nanoclusters containing the alkyne-embedded Au@Ag NPs and relatively small Ag NPs could be achieved by the mediation of CTAB through electrostatic forces and hydrophobic interaction, in which SCN−could be covalently bonded with the silver surface of NPs to form a compact molecular layer (–Ag–S–CN), and CTAB could only occupy remaining sites. In this process, we found that SCN−always runs counter to CTAB and tends to dissolve nanoclusters, so that they occupy the exposed surface of NPs in nanoclusters rather than the binding sites of one another. Remarkably, when the concentration of SCN−initially increased, two highly recognizable SERS emissions, which were assigned to alkyne reporter molecules (2208 cm−1) and CN of SCN−(2110 cm−1), respectively, were rapidly detected, and their ratios (I2110/I2208) increased linearly proportional to the concentration of SCN−over a range of 17 nM to 172 μM, with a limit of detection (LOD) of 10 nM. With the further increase of SCN−, small Ag NPs started to desorb from the surface of individual Au@Ag NPs and dissociated in the solution but did not contribute to SERS signals. Instead, the surface plasmon resonance (SPR) peak of pure silver NPs at 385 nm increased gradually in the range from 0.5 to 20 mM with an LOD of 0.2 mM. Of particular significance, this simple sensor in conjunction with surface-enhanced Raman-extinction spectroscopy can be used for the rapid detection of extensive samples with an ultra-wide detection window, such as body fluids (saliva, urine, and serum) and food (milk powder and brassica vegetables), which is far superior to that of ion chromatography (IC).

To clarify the effects of ferrite morphologies and contents on high-cycle fatigue property of pearlite–ferrite dual-phase (DP) steel used for fabrication of commercial vehicle crankshafts, two types of DP steels with different ferrite grain sizes (S10: 13.1 μm and S30: 21.4 μm) and ferrite contents (S10: ~ 9.5 vol.% and S30: ~ 30.4 vol.%) were prepared. Stress amplitude–logarithm of number of high cycles to failure fatigue of the two DP steels was evaluated. Experimental results showed a fatigue strength of 510 and 400 MPa for S10 and S30 steels, respectively, at 107cycles. Fatigue cracks in S10 steel extended preferentially along the grain boundary, but it was easy for crack propagation to extend within a pearlite colony to form a zigzag crack morphology. Crack roughness was enhanced and high stress was introduced to the crack surface due to this kind of crack propagation behavior, which has positive effects on slowing down crack propagation. However, the crack propagation in S30 steel mainly occurred inside the soft equiaxed coarse ferrite grain. Analysis revealed that little stress was introduced to the crack surface. These results show that it is possible to improve high cycle fatigue strength of pearlite–ferrite DP steel by appropriately manipulating the volume fraction and microstructure morphology of ferrite phase.

Background: Both thyroid-stimulating immunoglobulins immunoassay (TSI IA) and thyrotrophin receptor antibody immunoassay (TRAb IA) are commonly used for the diagnosis of Graves’ disease (GD). The aim of the present study was to compare the clinical diagnostic performance of these two methods. Methods: Sera were obtained from 1103 subjects presenting a variety of clinical conditions from three centers: 100 subjects with untreated GD, 200 with treated GD, 62 with autoimmune thyroid disease(AIT), 216 with other thyroid diseases (OTHER-T), 214 with non-thyroid autoimmune diseases (NTAD), 191 with other diseases (OD), and 120 healthy subjects (HS). Both TSI and TRAb IAs were performed for all 1013 serum samples. Bioassay was performed for 86 samples whose TSI results were inconsistent the TRAb assay results. Results: Comparing untreated GD patients with the control groups (AIT, NTAD, OTHER-T, OD, and HS) resulted in an area under the curve (AUC) of 0.992 for the TSI IA and 0.989 for the TRAb IA with no statistically significant difference observed between these AUC values (P?=?0.2733). The best TSI CDP (clinical decision point) value was 0.42?IU/L. The differences in sensitivity (100% vs. 95%, P?=?0.7991) and specificity (97.1% vs. 97.6%, P?=?0.9426) between the TSI and TRAb IA were not statistically significant. TSI IA had a higher agreement with the TSI bioassay than TRAb IA. Conclusion: The clinical diagnostic performance of the TSI IA for diagnosing Graves’ disease was very similar to that of the TRAb IA. TSI IA can be used to diagnose GD in the Chinese.

Chlorpyrifos (CPF) is an organophosphate insecticide commonly used to treat fruit and vegetable crops. CPF can cause severe adverse effects on body organs including the liver and central nervous system. This study investigated the CPF-induced inflammation in mice and explored the role of intestinal flora changes in liver inflammation. Adult C57BL/6 male mice were exposed to a CPF of 0.01-, 0.1-, 1- and 10-mg/kg bodyweight for 12 weeks. The mice in experimental group given CPF solution dissolved in corn oil vehicle by gavage, was administered by intraoral gavage for 5 days per week for 12 weeks. Histopathological examination and inflammatory factor detection were performed on mice liver tissue. Faeces were used for 16S ribosomal RNA high-throughput sequencing to explore the impact of CPF on intestinal flora structure and diversity. The results showed that 1- and 10-mg/kg CPF caused different degrees of liver focal inflammation. The structure of intestinal flora changed significantly in mice including the decreased beneficial bacteria (Akkermansia, Prevotella and Butyricimonas) and increased pathogenic bacteria (Helicobacter and Desulfovibrio). Meanwhile, the results of Q-RT-PCR showed that there was more total bacterial DNA in the liver tissue of the mice treated with 10-mg/kg groups. In conclusion, the imbalance of intestinal flora, the decreased abundance of beneficial bacteria and the increased abundance of pathogenic bacteria, as well as the increase of total bacterial DNA in the liver tissues, maybe associated with the liver focal inflammation induced by CPF.

Two-dimensional nanoelectronics, plasmonics, and emergent phases require clean and local charge control, calling for layered, crystalline acceptors or donors. Our Raman, photovoltage, and electrical conductance measurements combined with ab initiocalculations establish the large work function and narrow bands of α-RuCl3enable modulation doping of exfoliated single and bilayer graphene, chemical vapor deposition grown graphene and WSe2, and molecular beam epitaxy grown EuS. We further demonstrate proof of principle photovoltage devices, control via twist angle, and charge transfer through hexagonal boron nitride. Short-ranged lateral doping (≤65 nm) and high homogeneity are achieved in proximate materials with a single layer of α-RuCl3. This leads to the best-reported monolayer graphene mobilities (4900 cm2/(V s)) at these high hole densities (3 × 1013cm–2) and yields larger charge transfer to bilayer graphene (6 × 1013cm–2).

Nanoscale charge control is a key enabling technology in plasmonics, electronic band structure engineering, and the topology of two-dimensional materials. By exploiting the large electron affinity of α-RuCl3, we are able to visualize and quantify massive charge transfer at graphene/α-RuCl3interfaces through generation of charge-transfer plasmon polaritons (CPPs). We performed nanoimaging experiments on graphene/α-RuCl3at both ambient and cryogenic temperatures and discovered robust plasmonic features in otherwise ungated and undoped structures. The CPP wavelength evaluated through several distinct imaging modalities offers a high-fidelity measure of the Fermi energy of the graphene layer: EF= 0.6 eV (n= 2.7 × 1013cm–2). Our first-principles calculations link the plasmonic response to the work function difference between graphene and α-RuCl3giving rise to CPPs. Our results provide a novel general strategy for generating nanometer-scale plasmonic interfaces without resorting to external contacts or chemical doping.

To predict hot tearing susceptibility (HTS) during solidification and improve the quality of Al alloy castings, constitutive equations for AA6111 alloys were developed using a direct finite element (FE) method. A hot tearing model was established for direct chill (DC) casting of industrial AA6111 alloys via coupling FE model and hot tearing criterion. By applying this model to real manufacture processes, the effects of casting speed, bottom cooling, secondary cooling, and geometric variations on the HTS were revealed. The results show that the HTS of the billet increases as the speed and billet radius increase, while it reduces as the interfacial heat transfer coefficient at the bottom or secondary water-cooling rate increases. This model shows the capabilities of incorporating maximum pore fraction in simulating hot tearing initiation, which will have a significant impact on optimizing casting conditions and chemistry for minimizing HTS and thus controlling the casting quality.

4-(4-Nitrophenyl)morpholin-3-one and 4-(4-aminophenyl) morpholin-3-one are the key intermediates for rivaroxaban synthesis. A facile and economically efficient process has been developed for the preparation of these intermediates. Excellent yield of 4-(4-nitrophenyl)morpholine is obtained by condensing 4-chloro nitrobenzene and morpholine, and 4-(4-nitrophenyl)morpholine is oxidized using inexpensive sodium chlorite to achieve a good yield of the corresponding 4-(4-nitrophenyl)morpholin-3-one. Finally, the key intermediate of rivaroxaban, 4-(4-aminophenyl) morpholin-3-one, is achieved by the iron(III)-catalyzed reduction of the nitro group with aqueous hydrazine. No high-cost materials were used, and the process did not require column purification.

NiCo-layered double hydroxide (LDH) has attracted increasing attention in recent years for application in supercapacitors (SCs) owing to its high redox activity and intercalating capability. However, the pristine NiCo-LDH is unable to reach theoretical specific capacitance and satisfying rate capability due to the limited electroactive species and a low ion diffusion rate. Here, we demonstrate novel vertically aligned nanosheet arrays of cobalt metal–organic framework (Co-MOF)@CoNiO2core–shell composites constructed by the in situ grown Co-MOF shell with a uniform and controlled thickness on the CoNiO2core via a vapor-phase approach. Owing to the intimate contact and synergistic effect between the Co-MOF shell and the CoNiO2core, the as-synthesized Co-MOF@CoNiO2displays a high specific capacitance of about 571 F g–1, which is significantly higher than the pristine NiCo-LDH electrode (380 F g–1). Moreover, the capacitive properties of Co-MOF@CoNiO2can be further boosted to 757.2 F g–1after cyclic voltammetry oxidation. The easy preparation and high electrochemical performance of the Co-MOF@CoNiO2composite make it a potential material for SC application. These findings may inspire the exploration and construction of other MOF shell coating metal oxide from various nanostructured LDHs for varied applications. In addition, the as-assembled EO-Co-MOF@CoNiO2/carbon cloth (CC)//activated carbon (AC) device can achieve a high capacitance of 87.67 F g–1. Meanwhile, the asymmetric supercapacitor (ASC) device exhibits a high energy density of 27.4 Wh kg–1at a power density of 750 W kg–1.