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Recently, multitask learning has been successfully applied to survival analysis problems. A critical challenge in real-world survival analysis tasks is that not all instances and tasks are equally learnable. A survival analysis model can be improved when considering the complexities of instances and tasks during the model training. To this end, we propose an asymmetric graph-guided multitask learning approach with self-paced learning for survival analysis applications. The proposed model is able to improve the learning performance by identifying the complex structure among tasks and considering the complexities of training instances and tasks during the model training. Especially, by incorporating the self-paced learning strategy and asymmetric graph-guided regularization, the proposed model is able to learn the model in a progressive way from ``easy'' to ``hard'' loss function items. In addition, together with the self-paced learning function, the asymmetric graph-guided regularization allows the related knowledge transfer from one task to another in an asymmetric way. Consequently, the knowledge acquired from those earlier learned tasks can help to solve complex tasks effectively. The experimental results on both synthetic and real-world TCGA data suggest that the proposed method is indeed useful for improving survival analysis and achieves higher prediction accuracies than the previous state-of-the-art methods.

The magnitude and variation of the sediment loads transported by rivers have important implications for the functioning of river systems and changes in the sediment loads of rivers are driven by numerous factors. In this paper, the key drivers of changes in the sediment loads of the major rivers of China are identified by reviewing recent studies of changes in their sediment loads. Except for the Songhua River, which presents no clear tendency of change in runoff or sediment load, nearly all the major rivers of China are characterized by an apparent decline in annual sediment load. The total annual sediment load of major Chinese rivers transported to the coast decreased from 2.03 billion t/yr during the period 1955–1968 to 0.50 billion t/yr during the period 1997–2010. The primary drivers of changes in the sediment loads of the rivers are dam construction, implementation of soil and water conservation measures, catchment disturbance, agricultural practices, sand mining and climate change. Examples drawn from Chinese rivers are used to demonstrate the importance of these drivers. Construction of a large number of reservoirs in the Yangtze River basin represents the primary driver for the reduced sediment load of the Yangtze River. The implementation of soil and water conservation programmes is one of the key drivers for the sharp decline in the sediment load of the Yellow River. Catchment disturbance explains why the reduction of the sediment load of the Lancang-Mekong River at the Chiang Saen gauging station was much less than that at the Gajiu gauging station upstream. A reduction in sediment load resulting from the expansion of agricultural production may be the main driver for the reduced sediment load of the Huaihe River. The decrease in the sediment load of the Pearl River has been influenced by sand mining activities. Climate change is one of the key drivers responsible for the greatly reduced sediment load of the rivers in the Haihe River Basin.

α-Formamidinium lead iodide (α-FAPbI3) has become one of the most promising candidate materials for high-efficiency and thermally stable perovskite solar cells (PSCs) owing to their outstanding optoelectrical properties and high thermal stability. However, achieving a stable form of α-FAPbI3 where both the composition and the phase are pure is very challenging. Herein, we first report on a combined strategy of precursor engineering and grain anchoring to successfully prepare MA-free and phase-pure stable α-FAPbI3 films. Engineering the precursor solutions by incorporating volatile FA-based additives completely suppresses the formation of non-perovskite δ-FAPbI3 during film crystallization. Grains of the desired α-phase are anchored together and stabilized by permeating 4-tert-butyl-benzylammonium iodide into the α-FAPbI3 film interior via grain boundaries. This cooperative scheme leads to a significantly increased efficiency close to 21% for FAPbI3 perovskite solar cells (PSCs), which is among one of the highest values to date. Moreover, the stabilized PSCs exhibit improved thermal stability and maintained ~90% of their initial efficiency after storing at 50 °C for over 1600 hours. These findings should open new routes towards fabrication of high-quality perovskite films and optoelectronic devices.

Meandering rivers have dynamic evolution characteristics of lateral migration and longitudinal creeping movement, and studies on the migration rate of meandering rivers have both scientific and practical significance for understanding the evolution process. A river source region often is sparsely populated and lacks long-term monitoring data, making it difficult to estimate the migration rate of river bends. In the source region of the Yellow River, located in the northeastern part of the Qinghai-Tibet Plateau, China, meandering rivers have extensively developed. Combined with field investigation and sampling in the source region in 2016 and 2017, 9 river bends in the middle Baihe River were selected to attempt estimation of migration rates of the river bends using tree ring analysis. The tree core and disc samples were collected using an increment borer and a crosscut saw, and the ages of the trees were estimated based on tree ring analysis. A method for estimating the migration rate of river bends based on the relation between positions and ages of trees grown on the point bars in inner banks is proposed. The estimated migration rates of the 9 river bends of the Baihe River ranged 0.38–6.10 m/yr, and the migration rates were found to be related to the flow rate, channel slope, height of the outer bank, and width of the river valley. The maximum migration rate was determined to be at the No. 9 River Bend where the ratio of the meander-bend radius to the channel width (R/W) was 2.31, which is consistent with previous findings that the bend migration is most rapid in the ‘migration phase’. The proposed method for estimating the migration rate of river bends provides a potential alternative option for future study on the morphodynamic process of a meandering river.

In this paper, a novel triple-image encryption and hiding algorithm is proposed by combining a 2D chaotic system, compressive sensing (CS) and the 3D discrete cosine transform (DCT). First, three grayscale plain images are sparsely represented by the 2D discrete wavelet transform (DWT). The resulting sparse matrices are scrambled twice through index sort scrambling and 3D zigzag scrambling. Then, the measurement matrix generated by the 2D chaotic system is used to compress the scrambled matrices. Finally, the compressed matrices are embedded into a color carrier image using the 3D DCT to obtain a visually meaningful cipher image. It is worth mentioning that most of the existing meaningful encryption algorithms encrypt and embed single images, which cannot meet the requirements of the era of big data. However, in our scheme, three grayscale images are simultaneously encrypted and embedded into a single color carrier image, which, when compared with existing algorithms, greatly improves the encryption efficiency. Moreover, simulation experiments and contrastive analyses show that the proposed visual encryption scheme has excellent visual security, robustness, decryption quality and running efficiency.

Graph neural networks (GNNs) emerge as a powerful approach to process non-euclidean data structures and have been proved powerful in various application domains such as social networks and e-commerce. While such graph data maintained in real-world systems can be extremely large and sparse, thus employing GNNs to deal with them requires substantial computational and memory overhead, which induces considerable energy and resource cost on CPUs and GPUs. In this article, we present a specialized accelerator architecture, EnGN, to enable high-throughput and energy-efficient processing of large-scale GNNs. The proposed EnGN is designed to accelerate the three key stages of GNN propagation, which is abstracted as common computing patterns shared by typical GNNs. To support the key stages simultaneously, we propose the ring-edge-reduce(RER) dataflow that tames the poor locality of sparsely-and-randomly connected vertices, and the RER PE-array to practice RER dataflow. In addition, we utilize a graph tiling strategy to fit large graphs into EnGN and make good use of the hierarchical on-chip buffers through adaptive computation reordering and tile scheduling. Overall, EnGN achieves performance speedup by 1802.9X, 19.75X, and 2.97X and energy efficiency by 1326.35X, 304.43X, and 6.2X on average compared to CPU, GPU, and a state-of-the-art GCN accelerator HyGCN, respectively.

Mg(1-x)ZnxTa2O6 (x = 0.00−0.08) dielectric ceramics were synthesized via the traditional solid-state reaction method. We used XRD and Rietveld refinement to demonstrate that a pure Mg(1-x)ZnxTa2O6 phase with trirutile structure was formed. Zn2+ substitution helped to decrease the Raman full width at half width of the A1g mode at 703 cm−1, which resulted in an increase in the order and rigidity of the TaO6 octahedron, this in turn contributed to improving the Q×f values. Additionally, the introduction of Zn2+ significantly promoted grain growth and increased the dense, and the molecular polarizability, these factors lead to a higher permittivity. Moreover, enhanced Ta-O bond energy resulted in a more stable TaO6 octahedron in the Mg(1−x)ZnxTa2O6 system, which contributed to enhanced τf values via substitution of Zn2+ doped on the A-site. Correspondingly, the microwave dielectric properties were significantly improved for 0.04-doped samples, obtaining: er = 27, Q × f = 185,000 GHz (at 7.47 GHz), τf =32 ppm/°C.

Nano-whiskers based 3D Si3N4 porous ceramics (3D-NWSNPC) with high-porosity (about 91–93 %), low density (0.17–0.25 g/cm3), low thermal conductivity, and a certain degree of recoverability under cyclic compressive loading and reasonably strengths were prepared at 1423–1523 K via a one-pot foam-gelcasting/nitridation route using inexpensive commercial Si powders as starting materials and hexadecyl trimethyl ammonium bromide as foaming agent. After nitridation at 1523 K, the sample with an original solid loading of 12.5 wt% exhibited the highest compressive strength of 1.9 MPa, even though its density was lowered to 0.25 g/cm3. The sample nitrided at 1473 K had a relative density of 7.3 %. Its compressive and specific strength were respectively 1.1 MPa and 5.5 MPa·cm3 g−1, and its thermal conductivity was as low as 0.074 W/(m K) (measured at 323 K). These outstanding properties would make the as-prepared 3D-NWSNPC a promising candidate for applications in catalysis, filtration, thermal insulation and many other important areas.

The tether-net system is a promising technique for active debris removal. The capture process of a tether-net system for debris exhibits the nonlinear dynamics of very high dimensions and requires the dynamic simulation of high accuracy and efficiency in the design stage. This paper presents an integrated approach of both method of discrete elastic rods and algorithm of energy-conserving integration for the above purpose. The study shows that the method of discrete elastic rods is more suitable for modeling the extremely flexible threads of a woven net than the slender beam elements with C1 continuity. Besides, the energy-conserving integrator embedded in the present approach well conserves the total energy, and does not produce any numerical dissipations. The paper gives three numerical examples, including the capturing process of a hexagonal tether-net system for a space target, to demonstrate the advantages of the present approach, as well as the influence of some initial control parameters on the deployment phase of the tether-net system.

High-performance lithium ion capacitors (LICs) have been seriously hindered by the very low capacity and unclear capacitive mechanism of carbon cathode. Herein, after the combination of experimental results and theoretical calculations, it is found that the critical pore size of 0.8 nm for PF6− ion adsorption decreases strong interactive repulsion of electrons and largely reduces adsorption energy barrier, which greatly improves the charge accommodation capacity in electrical double-layer behavior. Most importantly, the chemical-bond evolution process of C=O group has been firstly revealed by X-ray photoelectron spectroscopy (XPS), indicating that the introduction of C=O group can provide abundant redox active sites for PF6− ion adsorption accompanied with enhanced pseudocapacitive capacity. Attributed to the synergistic effect of dual capacitive mechanism, porous carbon sheet (PCS) cathode shows a reversible specific capacity of 53.6 mAh g−1 even at a high current density of 50 A g−1. Significantly, the quasi-solid-state LIC manifests state-of-the-art electrochemical performances with an integrated maximum energy density of 163 Wh kg−1 and an outstanding power density of 15,000 W kg−1. This elaborate work promotes better fundamental understanding about capacitive mechanism of PF6− ion and offers a rational dual-capacitive strategy for the design of advanced carbon cathodes.

Escherichia coli O157:H7 (E. coli O157:H7) is a dangerous foodborne pathogen, mainly found in beef, milk, fruits, and their products, causing harm to human health or even death. Therefore, the detection of E. coli O157:H7 in food is particularly important. In this paper, we report a lateral flow immunoassay strip (LFIS) based on aggregation-induced emission (AIE) material labeling antigen as a fluorescent probe for the rapid detection of E. coli O157:H7. The detection sensitivity of the strip is 105 CFU/mL, which is 10 times higher than that of the colloidal gold test strip. This method has good specificity and stability and can be used to detect about 250 CFU of E. coli O157:H7 successfully in 25 g or 25 mL of beef, jelly, and milk. AIE-LFIS might be valuable in monitoring food pathogens for rapid detection.

Neuroscience research studies have shown that the left and right hemispheres of the human brain response differently to the same or different emotions. Exploiting this difference in the human brain response is important to emotion recognition. In this study, we propose a bi-hemisphere discrepancy convolutional neural network model (BiDCNN) for electroencephalograph (EEG) emotion recognition, which can effectively learn the different response patterns between the left and right hemispheres, and is designed as a three-input and single-output network structure with three convolutional neural network layers. Specifically, to capture and amplify different electrical responses of the left and right brain to emotional stimuli, three different EEG feature matrices are constructed based on the International 10–20 System. Subsequently, by using three convolutional neural network layers, the spatial and temporal features are extracted to mine the inter-channel correlation among the physically adjacent EEG electrodes. We evaluate our proposed BiDCNN model on the classical dataset called DEAP to verify its effectiveness. Our results of the subject-dependent experiment show that BiDCNN achieves state-of-the-art performance with a mean accuracy of 94.38% in valence and 94.72% in arousal, where the data for training and testing come from one subject. Furthermore, our subject-independent experimental results, in which different subjects are used to train and test the model, show that BiDCNN also obtains superior results on the valence and arousal recognition tasks, respectively achieving an accuracy of 68.14% and 63.94%.

Ni2+ modified MgTa2O6 ceramics with a trirutile phase and space group P42/mnm were obtained. The correlations between crystallographic characteristics and microwave dielectric performance of MgTa2O6 ceramics were systematically studied based on the chemistry bond theory (PVL theory) for the first time. The results indicate that the introduction of Ni2+ causes a change in polarizability and the Mg–O bond ionicity, which contributes to the variation of dielectric constant. Moreover, the lattice energy, and packing fraction, full width at half maximum of the Raman peak of Ta–O bond, as the quantitative characterization of crystallographic parameters, regulate the dielectric loss of MgTa2O6 ceramics in GHz frequency band. In addition, the study of sintering behavior shows that the densification and micromorphology are the crucial factors affecting the microwave dielectric performance. Typically, Ni2+ doping on the A-site of MgTa2O6 can effectively promote the Q × f values to 173,000 GHz (at 7.43 GHz), which ensures its applicability in 5G communication technology.

Uneven development theory and its corollary (i.e. rent-gap theory) are either excessively general or insufficiently flexible to expound the variations of gentrification with unique historical trajectories. A representative example is education-led gentrification in China. The lacuna restricts the explanatory power of rent-gap theory and justifies the fault line between the rent gap and two important phenomena: the forms of displacement identified by Marcuse and territorial stigmatisation. This paper recasts Neil Smith's insights about uneven development from two perspectives, temporal and social differentiations, and elaborates how the interplay between both differences engenders territorial stigmatisation and displacement. Moreover, as two diametrically opposed phenomena, territorial glorification (e.g. super-gentrification and education-led gentrification) and territorial stigmatisation are simultaneously situated in one framework, which is evaluated in education-led gentrification in Nanjing. Redirecting the empirical research from global cities to less established but more representative urban centres, this research shows the potentially wide applicability of the theoretical framework.

In recent years, chemodynamic therapy (CDT) has gained increasing interest in cancer treatment. In contrast to photodynamic therapy and sonodynamic therapy, extrinsic excitations such as laser or ultrasound are not required in CDT. As a result, the CDT performance is not limited by the penetration depth of the external irritation. However, CDT relies heavily on hydrogen peroxide (H2O2) in the tumour microenvironment (TME). Insufficient H2O2 in the TME limits the CDT performance, and the most reported methods to produce H2O2 in the TME are dependent on oxygen supply, which is restricted by the hypoxic TME. In this study, H2O2 self-providing copper nanodots were proposed, and the drug doxorubicin (DOX) was successfully loaded to construct DOX-nanodots. Our results showed that the nanodots produced H2O2 in the weakly acidic TME due to the peroxo group and further generated the most active hydroxyl radical (OH) through the Fenton-like reaction. This process was pH-dependent and did not occur in a neutral environment. In addition to OH, the nanodots also produced singlet oxygen (1O2) and superoxide anions (O2-) in the cancer cells. The copper nanodots performed promising CDT against breast cancer in vitro and in vivo, with enhanced cell apoptosis and decreased cell proliferation. The combination of chemotherapy and CDT using DOX-nanodots further improved the therapeutic effects. The treatments showed good biocompatibility with no obvious toxicity in major tissues, possibly due to the specific OH generation in the weakly acidic TME. In summary, the H2O2 self-providing copper nanodots in combination with DOX showed promising cancer-curing effects due to the oxygen-independent and tumour-specific production of reactive oxygen species and the cooperation of chemotherapy.

The porous morphology and secondary phase originated from lithium evaporation have deteriorated dielectric properties of Li2Mg3SnO6 ceramic. To solve this issue, a set of non-stoichiometric Li2Mg3-2xSn1-xO6 (x = −0.04, −0.02, 0.00, 0.02, 0.04, 0.06) samples were prepared by the solid-state method. Subsequently, the effects of non-stoichiometry on the structural evolution, microstructure and dielectric properties of rock salt-type Li2Mg3-2xSn1-xO6 ceramics were investigated. The Rietveld refinement and SEM results confirmed that moderate non-stoichiometry could eliminate secondary phase and promote densification. For −0.04 ≤ x ≤ 0.04, the upward tendency of dielectric constant (er) and quality factor (Q×f) was dominated by the improved phase purity and densification. As 0.04 ≤ x, the deterioration of dielectric characteristics was explained by the dielectric polarizability, lattice energy and packing fraction. The temperature coefficient of resonance frequency (τf) shifted from −36.41 to −27.23 ppm/°C, which could be attributed to the poor thermostability of Mg2SnO4 (τf = −64 ppm/°C) and enhanced octahedra bond energy.

The high cost and platinum dissolution issues of counter electrodes (CEs) are two core problems for the development of dye-sensitized solar cells (DSSCs). In this work, different CEs based on binary alloy Ru81.09Co18.91, Ru80.55Se19.45 and Co20.85Se79.15 nanostructures for DSSCs were successfully synthesized and investigated by a facile and environmentally friendly approach. Here, we found that the Co20.85Se79.15 alloy CE-based device yields the higher photoelectric conversion efficiency of 7.08% compared with that (5.80%) of the DSSC using a pure Pt CE because of the larger number of active sites with improved charge transferability and reduced interface resistance by matching work function with the I3‒/I‒ redox electrolyte. The inexpensive synthesis method, cost-effectiveness and superior catalytic activity of the Co20.85Se79.15 alloy may open up a new avenue for the development of CEs for DSSCs in the near future.

The microstructure，texture distribution and tensile property of 7xxx ultra-thick plate was investigated by optical microscopy (OM), scanning electron microscopy (SEM), electron back scattering diffraction (EBSD), transmission electron microscopy (TEM) and tensile tests. The results show that the microstructure, texture and tensile property were inhomogeneous along the thickness direction. A large number of sub-crystals remained on the surface of the thick plate and was accompanied by much recrystallization. Most of the structures were random texture, and the proportion of typical texture was low at the edge. For the center layer, there were also a lot of recrystallized grains and typical deformed texture along the β-fiber (Brass, S, and Copper) was observed. The 1/4 layer of the plate is a transition one, and had the lowest recrystallized fraction. From surface to center, precipitation phases within grains and grain boundaries gradually coarsen, mechanical properties reduced. At the same thickness, the tensile property showed appreciable anisotropy, the L direction was the highest and the S direction was the lowest.

Welding properties of three alloys with different Cu contents (0.1, 0.4 and 0.9 wt.%) is studied by means of melt inert-gas welding (MIG). The results showed that, with the increase of Cu content from 0.1 wt.% to 0.9 wt.%, the strength and elongation increased obviously. When the Cu content was 0.9 wt.%, the strength and elongation reached 375MPa and 15%, respectively, which is a better match for bearing structure part of vehicles application. Besides, the adding of Cu element provided an increase limit for welding joint strength. Due to abundant coarse phases in fusion zone (FZ) and welding zone (WZ), the strength slightly increased and the failure fracture was different compared with that of 0.1Cu and 0.4Cu alloy. Present result was meaningful and valuable for pushing aluminum application automobile structural parts and other engineering components.

International audience; A simple and readily applicable voltammetric approach is described to characterize and measure thesite-hopping surface diffusion of underpotential-deposited (UPD) metal adatoms at nanoelectrodes. UPD refers tothe deposition of atoms on foreign metal supports at potentials lower than those predicted by Nernst law for a bulkdeposition. Despite its importance in several fields of catalysis, advanced nanofabrication or even atomicnanoengineering by atomic layer epitaxy, diffusion of UPD adatoms is difficult to observe at micro- andmacroelectrodes. In fact, at electrodes of usual dimensions, UPD adatoms surface diffusion is masked by otherelectrochemical phenomena of greater relative amplitudes. Conversely, at nanowires electrodes sealed in glass,only an extremely small fraction of the surface of the wires is exposed to the electrolyte solution and is rapidlyloaded. This allows the spillage of UPD adatoms onto the much larger area of the nanowire rod which is immuneto Faradaic reactions due to its isolation from the electrochemical solution by the glass casing. Therefore,surprisingly for a UPD process, voltammetric peaks currents and integral desorption charges primarily reflect thesediffusional surface processes so that the integral charges vary linearly with the inverse of the square root of thescan rate. This is easily observable and measurable with usual bench-level electrochemical instrumentation. In thiswork, by using nanoelectrodes with diameters between 90 and 260 nm, we were able to establish the majorinvolvement of this site-hopping surface diffusion of UPD Pb adatoms on polycrystalline gold (Au) and characterizeit quantitatively. The equivalent surface diffusion coefficient of UPD Pb adatoms was determined to be ~4.4 × 10-11 cm2 s-1 at room temperature, corresponding to a Gibbs free energy activation barrier of ca. 18.72 kJ mol-1 (i.e.,0.19 eV per Pb adatom) for the reaction of inter-sites exchange of Pb adatoms on a polycrystalline Au surface.

Wolframite-structured Mg1-xCaxZrNb2O8 (0−0.1) ceramics were synthesized through a solid-state procedure. Crystal refinement indicates a pure Mg1-xCaxZrNb2O8 ceramic with a wolframite structure. Ca2+ substitution led to the redshift of the Ag mode at approximately 896 cm−1. Additionally, Ca2+ substitution could promote grain growth and contribute to microstructure evolution from a polyhedral shape to a rod shape. According to chemical bond theory, an appropriate Ca2+ concentration can increase Nb O bond iconicity and Nb O bond lattice energy, which contributed to the great improvement in the dielectric constant and Q × f value. Additionally, the τf value was affected by the bond valence and thermal expansion coefficient of the Mg O bond. The Mg1-xCaxZrNb2O8 (x = 0.04) ceramics exhibited great improvement in the Q × f value: er = 25.21, Q × f = 116,000 GHz (@7.17 GHz) and τf = −24.4 ppm/°C, which provides enormous potential for future millimeter-wave applications.

In this study, a method of surface texture is considered to improve the frictional performance of the ring-liner system (i.e. RLS) under the conditions of cylinder deactivation (i.e. CDA). To assess the effectiveness of the method, a lubrication model is developed with considerations of the liner deformation, the actual rheological properties of lubricant, and the lubricant transport. By solving the model numerically, the friction reduction effect of surface texture for the RLS under the CDA is investigated. The results show that the surface texture can improve the friction properties significantly. For a six-cylinder gasoline engine, 7.57% and 7.28% decreases in the total average friction loss and power loss are observed when the RLS under the CDA is surface textured.

Considering both the effect of the nonisothermal nature of the interface as well as the effect of forced convection, an extended free dendritic growth model for binary alloys was proposed. Comparative analysis indicates that the effect of convection on solute diffusion is more remarkable compared with the ignorable effect of convection on thermal diffusion at low bath undercooling, due to the fact that solute diffusion coefficient is usually three orders of magnitude less than thermal diffusion coefficient. At high bath undercooling, the effect of convection on the dendritic growth is very slight. Furthermore, a satisfying agreement between the model predictions with the available experiment data for the Cu70Ni30 alloy was obtained, especially at low bath undercoolings, profiting from the higher values of interfacial migration velocity predicted by the present model with nonideal fluid case than that predicted by the one ignoring the effect of convection.

To suppress the impurity phases and porous microstructure caused by lithium volatilization, the Li2Mg3ZrO6 and Zr-deficiency Li2Mg3Zr1-xO6 (x = 0.02, 0.04, 0.06, 0.08, 0.10) ceramics were successfully synthesized via the solid-state method assisted with atmosphere-controlled sintering. The influences of non-stoichiometric on structure characteristics, morphology and microwave dielectric properties of Li2Mg3Zr1-xO6 ceramics were investigated. The XRD and SEM results proved that the Zr-deficiency restrained the formation of impurity phases and remarkably improved the densification of Li2Mg3Zr1-xO6 samples. The variation trend of dielectric constant (er) was explained by the relative density and theoretical dielectric polarizability. The quality factor (Q × f) was strongly associated with the impurity phases and relative density. Additionally, the temperature coefficient of resonant frequency (τf) showed the same trend as the total bond energy Etotal, indicating the bond energy might play vital roles in thermal stability of Li2Mg3Zr1-xO6 samples. Typically, the Li2Mg3Zr1-xO6 sample obtained at x = 0.06 possessed remarkable dielectric performances: er = 13.13, Q × f = 116,400 GHz (10.14 GHz) and τf = −26.30 ppm/°C.

Laryngoscopes are widely used in the clinical diagnosis of laryngeal lesions, but such diagnosis relies heavily on the physician's subjective experience. The purpose of this study was to develop a computer-aided diagnostic system for the detection of laryngeal lesions based on objective criteria. This study used the distinct features of the image contour to find the clearest image in the laryngoscopic video. First to reduce the illumination problem caused by the laryngoscope lens, which could not fix the position of the light source, this study proposed image compensation to provide the image with a consistent brightness range for better performance. Second, we also proposed a method to automatically screen clear images from laryngoscopic film. Third, we used ACM to segment automatically them based on structural features of the pharynx and larynx, using hue and geometric analysis in the vocal cords and other zones. Finally, the support vector machine was used to classify laryngeal lesions based on a decision tree. This study evaluated the performance of the proposed system by assessing the laryngeal images of 284 patients. The accuracy of the detection for vocal cord polyps, cysts, leukoplakia, tumors, and healthy vocal cords were 93.15%, 95.16%, 100%, 96.42%, and 100%, respectively. The cross-validation accuracy for the five classes were 93.1%, 94.95%, 99.4%, 96.01% and 100%, respectively, and the average test accuracy for the laryngeal lesions was 93.33%. Our results showed that it was feasible to take the hue and geometric features of the larynx as signs to identify laryngeal lesions and that they could effectively assist physicians in diagnosing laryngeal lesions.

2D materials is a promising Na+ insertion-type material due to its unique layered structure, however, the long diffusion channels yielded by stacking limited the Na+ storage rate capability. Herein, a 3D MoS2–Ta4C3 heterostructure (M-Ta4C3) composite is designed by supported 2D MoS2 nanosheets on/in the surface/interlayers of 2D Ta4C3 matrix for achieving high rate Na+ storage. The 2D MoS2 nanosheets is confined in the interlayers of Ta4C3 matrix that can avoid the stacking and expand the interlayer spacing of Ta4C3 matrix, which enlarges the contact surface area between electrode and electrolyte, and exposes more electrochemical active sites for Na+ storage. The Ta4C3 matrix improves the conductivity, prevents the aggregation and confines the volume expansion of MoS2 nanosheets which optimizes the structure stability and provides short Na+ diffusion channels. The M-Ta4C3 exhibits a larger interlayer spacing of 1.69 nm, extraordinary electrochemical performance and outstanding rate capability which benefitted from the 3D heterostructure. The M-Ta4C3//AC SIC owns super energy and power densities of 87.6 Wh kg−1 and 3937.3 W kg−1. This work employs Ta4C3 MXene as a Na+ storage material for the first time, and it provides an idea to improve the Na+ storage performance of 2D materials by constructing a 3D heterostructure.

In recent years, crystalline-driven self-assembly (CDSA) has received enormous attention, but almost only for block copolymers (BCPs). Herein, we introduced perfluorocarbon chains into main-chain-type liquid crystalline alternating copolymers (ACPs) to obtain perfluoroalkane-containing ACPs with periodic C-I bonds in polymer backbones via step transfer-addition and radical-termination (START) polymerization, followed by an iodine reduction reaction of C-I bonds to induce CDSA of ACPs and put forward a novel concept of "reduction-induced crystallization-driven self-assembly" (RI-CDSA) of main-chain-type ACPs for the first time. Finally, we proposed the folded-chain model and mechanism to explain the novel RI-CDSA behavior, and its rationality has been proved by the corresponding experimental results.

The article established a modelling that predicted and measured the quenching and pre-stretching stress in 7050 aluminum alloy thick plate in order to make the alloy suitable enough for manufacturing in the aerospace industries. The results show that both the rolling direction component stress and the transverse direction component stress have a “M” distribution along the plate thickness of 7050 aluminum alloy thick plate, but the level is slightly different, but the level is slightly different. The maximum value of quenching residual stress is about 187MPa in the 80mm thick of 7050 plate. Pre-stretching of the heat treated and quenched alloy to 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0% and 3.5% to reduce the residual stresses. It has been recorded that more than 90% reduction of residual stresses were observed in a pre-stretching rage of 2-3%. Measuring the surface residual stresses of the alloy by ultrasonic methods and measuring the internal residual stresses of the alloy by crack compliance methods. The two methods are used to verify the model. The difference between the measurement and the simulation is within 40MPa. The experimental data of the ultrasonic and the crack compliance methods were found to correspond well with the simulated models. This shows that the simulation model can effectively predict the evolution of residual stress in 7050 aluminum alloy thick plate, and the simulation model can also be reconstructed and inspected through the experimentally measurement.

Sodium-ion capacitors (SICs) are extremely promising due to the combined merits of high energy-power characteristics and considerable price advantage. However, it is still difficult to achieve high energy-power outputs and cycle stability in a typical configuration of the metal-based battery-type anode and activated carbon capacitor-type cathode due to the kinetic mismatching. In this work, a carbon nanosheet (PSCS-600) with large interlayer spacing of 0.41 nm derived from the bio-waste pine cone shell was prepared. Besides, the covalent triazine framework derived carbon (OPDN-CTF-A) was obtained through ionothermal synthesis strategy, exhibiting beneficial hierarchical pores (0.5–6 nm) and high heteroatoms (5.6 at% N, 6.6 at% O). On this basis, the all-carbon SICs were fabricated by the integration of PSCS-600 anode and OPDN-CTF-A cathode. The device delivered high energy density 111 Wh kg−1, high power output of 14,200 W kg−1 and ultra-stable cycling life (∼90.7% capacitance retention after 10,000 cycles). This work provides new ideas in fabricating carbon-carbon architectural SICs with high energy storage for practical application.

Objectives The aim of this study is to improve the biological and mechanical properties of zirconia-based PICN (polymer-infiltrated-ceramic-network) materials by fabrication an enamel-like structure on its surface. Methods Fluorapatite (FA) arrays were fabricated on zirconia discs by hydrothermal treatment. After polymer infiltration, an enamel-like structure was obtained on zirconia-based PICN materials. Effects of hydrothermal treatment conditions on the FA arrays were investigated by XRD, FTIR and SEM. Human gingival fibroblast cells (HGFs) and Escherichia coli (E. coli) were used to evaluate the cytocompatibility and antibacterial properties. Nanoindentation method was employed to determine elastic modulus and hardness. Results A facile and pervasive method was developed in this study to fabricate an enamel-like structure constituted of controlled FA arrays and interstitial resin on zirconia-based PICN materials. The obtained FA arrays can significantly promote the adhesion and proliferation of human gingival fibroblasts (HGFs), and further effectively inhibit the growth of Escherichia coli. Owing to the hierarchical structure, the enamel-like structure has achieved a hardness of 1.79 GPa and a lower Young’s modulus of 37.4 GPa. Significances The enamel-like structure, with excellent biological and mechanical properties, is promising for various applications in dentistry.

In this paper, a phase-shifted full-bridge current-doubler synchronous rectifying converter (PSFB-CDSRC) based on IGBT and its control strategies are studied. In the main circuit, a current doubling synchronous rectifying circuit based on IGBT is presented to further reduce the power loss of power devices. Moreover, in the control strategy, in view of the existing researches, the basic BP neural network PID control performance of the rectifying converter still can be further improved. Therefore, this paper combines the quasi-Newton algorithm and traditional GA to propose an improved GA-BP (IGA-BP) neural network to further improve PID control performance. The simulation results demonstrate that the maximum efficiency of 5 V/500 A rectifying converter based on the proposed circuit scheme can reach 94.1%, and the rectifying converter has a good performance of excellent waveform and wide range of load. IGA-BP neural network PID control responds fast and reaches the stable state quickly in comparison with that controlled by the GA-BP neural network control strategy, and the steady-state time can be reduced by 10.5% through using IGA-BP neural network control strategy. This study can provide a valuable guidance and reference, not only in circuit scheme but also in the optimal PID control strategy for design of the high-efficiency DC/DC rectifying converter with higher power in the future.

Nanofibers with hollow or porous network structure have numerous prospective realistic applications in electrode materials of a hybrid supercapacitor. Herein, La0.7Sr0.3CoO3/Co3O4 nanofibers (LSC/Co3O4 NFs) with hollow network porous structure where Co3O4 nanoparticles evenly distributed in the LSC single tube both sides of hollow are successfully prepared by one-step electrospinning. Electrochemical characteristics of LSC-doped composite electrode materials with different proportions have studied in detail. The result showed the LSC (20 wt%)/Co3O4 electrode material displayed the eminent specific capacity of 215 C g-1 (430 F g-1) at 1 A g-1. Furthermore, the LSC (20 wt%)/Co3O4//AC hybrid supercapacitor showed remarkable cyclic stability after 5000 cycles with a capacity retention of 86.3% and it showed a tremendous energy density of 21.9 Wh kg-1 at a power density of 358.4 W kg-1. Hence, the prepared LSC/Co3O4 NFs have promised a new type of electrode for hybrid supercapacitors.

This study mainly aims to hindcast historical Typhoon Nepartak (2016) and to analyze tide–surge and wave interactions. To achieve this goal, a coupled tide–surge–wave model was built around the coast of Taiwan, and it was applied to simulate storm surges and waves during historical typhoon event. To demonstrate its capability, the coupled model was validated with observed water levels, wind speeds, atmospheric pressures, wave heights, and wave periods at different stations. Quantitatively, the model results reasonably reproduced the observed data. Furthermore, the model was utilized to explore the tide, surge, and wave interaction using historical Typhoon Nepartak (2016). The model results revealed that onshore wind enhanced the surge height, while offshore wind decreased the surge height. The atmospheric pressure consistently displayed a positive contribution to surge height. The wind-induced surge height contributing to the total surge height was 136.83% at Taichung Harbor, because the offshore wind mainly dominated the surge height compared to the effect of atmospheric pressure. The atmospheric pressure-induced surge heights contributing to the total surge height were 100.59%, 96.26%, and 99.74% at Kaohsiung Harbor, Hualien Harbor, and Taitung Fugang, respectively, as a result of the atmospheric pressure dominating the surge height. However, the contribution of the wave setup to the total surge height was minor. The path of typhoons at different time frames significantly affected the spatial distributions of surge height and wave height around the coast of Taiwan. The contributions of water level and current to wave height reached a maximum value of approximately 0.3 m at Suao, while the contributions at Penghu, Qigu, and Eluanbi were all less than 0.2 m. This signified that the influence of the water level and current on wave height was not negligible.

Prior works typically conducted the fault analysis of neural network accelerator computing arrays with simulation and focused on the prediction accuracy loss of the neural network models. There is still a lack of systematic fault analysis of the neural network acceleration system that considers both the accuracy degradation and system exceptions, such as system stall and running overtime. To that end, we implemented a representative neural network accelerator and corresponding fault injection modules on a Xilinx ARM-FPGA platform and evaluated the reliability of the system under different fault injection rates when a series of typical neural network models are deployed on the neural network acceleration system. The entire fault injection and reliability evaluation system is open-sourced on GitHub. With comprehensive experiments on the system, we identify the system exceptions based on the various abnormal behaviors of the FPGA-based neural network acceleration system and analyze the underlying reasons. Particularly, we find that the probability of the system exceptions dominates the reliability of the system. The faults also incur accuracy degradation of the neural network models, but the influence depends on the applications of the models and can vary greatly. In addition, we also evaluated the use of conventional triple modular redundancy (TMR) and demonstrated the challenge of TMR with both experiments and analytical models, which may shed light on the reliability design of the FPGA-based neural network acceleration system.

To investigate the effects of (Al0.5Ta0.5)4+ substitution on the crystal structure and dielectric characteristics of Li2Mg3TiO6, a set of Li2Mg3Ti1-x (Al0.5Ta0.5)xO6 (x = 0.0–0.12) samples were fabricated via solid-state process. XRD and Rietveld refinement results confirmed the formation of single rock salt structure in the space group Fm3m (No.225) within 0.0 ≤ x ≤ 0.12. Subsequently, some intrinsic factors were introduced to evaluate the structure dependence of dielectric characteristics in Li2Mg3Ti1-x (Al0.5Ta0.5)xO6 ceramics based on the unit cell parameters. The variation trend of dielectric constant (er) was explained by the relative density and average ionic polarizability. The quality factor (Q × f) showed the same trend as the packing fraction and lattice energy, indicating the intrinsic lattice anharmonicity might play vital roles in dielectric loss. Additionally, the temperature coefficient of resonant frequency (τf) was strongly associated with the bond energy of Etotal. Typically, the Li2Mg3Ti0.91(Al0.5Ta0.5)0.09O6 sample obtained at 1310 °C possessed remarkable dielectric performances: er = 15.06, Q × f = 169,600 GHz and τf = −27.45 ppm/°C.

Traditionally, tidal level is predicted by harmonic analysis (HA). In this paper, three hybrid models that couple varied pre-processing methods, which are empirical mode decomposition (EMD), ensemble empirical mode decomposition (EEMD), and empirical wavelet transform (EWT), with the nonlinear autoregressive networks with exogenous inputs (NARX) were applied to forecast tidal level. The models were, namely, EMD-NARX, EEMD-NARX, and EWT-NARX. The sub-series obtained by using EMD or EEMD or EWT were then used as the input vectors to the NARX with the original data as targets. Notably, the EWT-NARX model was employed to predict the tidal level for the first time. Simulations were based on the measurements from four tidal stations at the Pearl River Estuary, China. The results showed that the EWT-NARX, EEMD-NARX, and EMD-NARX outperformed the HA model. Specifically, EWT-NARX was optimal among the four. Moreover, from the Hilbert energy spectra we can see the EWT solved the mode-mixing problem that EMD and EEMD suffered from, thus enabling precise tidal level prediction. Simulations and experimental results confirmed that the EWT-NARX model can achieve prediction of the tidal level with high accuracy. HIGHLIGHTS EWT-NARX model was applied to predict the tidal level for the first time.; EWT-NARX outperformed EEMD-NARX, EMD-NARX, and harmonic analysis.; EWT solves the mode-mixing problem that EMD and EEMD suffered so that the EWT-NARX model has better prediction performance.

Sericin, a silk protein, has a high potential for use as an extracellular matrix in tissue engineering applications. In this study, novel gelatin (GEL) and silk sericin (SS) were incorporated with a polyvinyl alcohol) PVA hydrogel nanocomposite (GEL-SS-PVA) scaffold that can be applied to repair cartilage. Glutaraldehyde was used as a cross-linking agent, with hydrochloric acid acting as an initiator. The microstructure characteristics of the obtained GEL-SS and GEL-SS-PVA scaffolds were also examined using FTIR and XRD spectra and their enhanced thermal stability was assessed by TGA. The blended GEL-SS and GEL-SS-PVA scaffolds were confirmed by SEM analysis to be highly porous with optimum pore sizes of 172 and 58 µm, respectively. Smaller pore sizes and improved uniformity were observed as the concentration of PVA in the GEL-SS-PVA scaffold increased. PVA decreased the tensile strength and elongation of the membranes but increased the modulus. Swelling studies showed high swellability and complete degradation in the presence of phosphate-buffered saline. Cytocompatibility of the GEL-SS-PVA scaffolds showed that these had the highest potential to promote cell proliferation as evaluated with standard microscopy using L929 fibroblasts. The prepared GEL-SS composite scaffold incorporated with the PVA hydrogel was implanted in full-thickness articular cartilage defects in rats. The repair effect of cartilage defects was observed and evaluated among the GEL-SS-PVA, GEL-SS, and control operation groups. The defects were almost completely repaired after 14 weeks in the GEL-SS-PVA group, thereby indicating that the GEL-SS-PVA composite had a favorable effect on articular cartilage defects in rat knee joint repair.

In recent years, urgent needs for counting crowds and vehicles have greatly promoted research of crowd counting and density estimation. Benefiting from the rapid development of deep learning, the counting performance has been greatly improved, and the application scenarios have been further expanded. Aiming to deeply understand the development status of crowd counting and density estimation, we introduce and analyze the typical methods in this field and especially focus on elaborating deep learning-based counting methods. We summarize the existing approaches into four categories, i.e., detection-based, regression-based, convolutional neural network based and video-based. Each category is explicated in great detail. To provide more concrete reference, we compare the performance of typical methods on the popular benchmarks. We further elaborate on the datasets and metrics for the crowd counting community and discuss the work of solving the problem of small-sample-based counting, dataset annotation methods and so on. Finally, we summarize various challenges facing crowd counting and their corresponding solutions and propose a set of development trends in the future.

In this paper, to improve the current efficiency in the copper electrowinning process is taken as the research objective. In the traditional production process, sulfate ion concentration, copper ion concentration and current density are carried out according to the empirical value, which cannot ensure the current efficiency to reach the optimal level. Therefore, firstly, this paper proposes a BP neural network model to improve the current efficiency according to the relationships between sulfate ion concentration, copper ion concentration, current density and the established BP neural network model is trained by using real data from the enterprise. The simulation results indicate that there is a definite error between the predicted current efficiency and corresponding to the current efficiency measured at the production site. It is proposed that the BP neural network improved by the improved PSO to further improve the prediction accuracy of the BP neural network. Simulation results indicate that the prediction error of the current efficiency is greatly reduced that meets the accuracy requirements. On the premise of guaranteeing the quality of copper electrowinning, the current density, sulfate ion concentration and copper ion concentration corresponding to the maximum current efficiency accurately predicted by this method can be respectively adjusted in real-time in the copper electrowinning process, which realizes the optimization of current efficiency in the process of copper electrowinning under the background of low carbon and environmental protection.

The tailings dam safety monitoring system is a system that plays an important role in disaster prevention and reduction. This paper divides the whole network of mine dam safety monitoring systems into two parts, that is, the basic wireless network and GPRS network from the gateway to the monitoring center. First, it’s the hardware of the design module, the network is divided into uplink communication and downlink communication, uplink communication is to upload the dam data collected by the terminal node to the gateway through the network. Downlink communication is the instruction sent by the gateway to the monitoring center, send to terminal nodes through data conversion between protocols. Secondly, the gateway also needs to solve the data conversion between the network and GPRS network protocol, so that the entire security monitoring system can communicate accurately. The communication between gateway and monitoring center is realized through the GPRS network, this requires adding the GPRS communication module to the gateway module. To increase the diversity of communications, communication between GSM short message communication methods and monitoring centers has also increased. The experimental results prove that the system in this paper can be applied to the mine dam safety monitoring system, meet the design requirements.

Acute hypotensive episode (AHE) is a common serious postoperative complication in ICU, which may raise multiple system failure (especially of cardiac and respiratory kinds), and even cause death. Timely and effective clinical intervention is obviously vital to the saving of patients. AHE detection involves physiological time-series monitoring, processing and prediction technologies, which can offer insights to neuroscientists, biologists, and even provide support for clinicians. This paper presents a hybrid artificial intelligence model combined with CEEMDAN (complete ensemble empirical mode decomposition with adaptive noise, a typical method for physiological signal decomposition), deep learning, multiple gene expression programming and fuzzy expert system for AHE detection. In this paper, the physiological signal is selected from a benchmark dataset, for example MIMIC-II (Multiparameter Intelligent Monitoring in Intensive Care II), which collects large scale real patients’ data for clinical research. In the hybrid model, a typical signal decomposition method is employed for AHE signal processing, and an autoencoder based deep neural network is established for feature extraction. Finally, a reliable and explainable classifier is presented by fusing gene expression programming and the fuzzy method. Experimental results based on real data set demonstrate that the proposed method outperforms state-of-the-art AHE detection methods by achieving the prediction accuracy of 88.14% in 2866 records.

CaTi1-x (Mg1/2W1/2)xO3 (x = 0, 0.02, 0.04, 0.06, 0.08) dielectric ceramics were synthesized via the traditional solid-state reaction method. Crystal structure and microwave dielectric properties of CaTi1-x (Mg1/2W1/2)xO3 system were systematically investigated based on chemistry bond theory (P–V-L theory) for the first time. The pure perovskite phase was obtained for all doped samples, as confirmed through the XRD and Rietveld refinement results. The lattice characteristics were closely related to the microwave dielectric properties. The bond ionicity, lattice energy, and bond energy affected the dielectric constant, quality factor, and temperature stability of the ceramic material. Through the use of (Mg1/2W1/2)4+ doped on B-site, the CaTi1-x (Mg1/2W1/2)xO3 system can maintain a high dielectric constant (er > 100) while effectively reducing the τf value from 800 ppm/°C to less than 300 ppm/°C and improving the Q × f value to 9650 GHz (at 3.76 GHz).

Effective liberation of chlorine (Cl) as a recoverable product such as hydrochloric acid is crucial for the clean disposal of massive Cl-bearing industrial solid waste. This study aims to clarify the evolution of Cl upon the pyrohydrolysis of CaCl2 waste. Particularly, the use of silica and MgCl2 to promote the breakage of Ca-Cl bonds to release HCl gas has been investigated, via synchrotron X-ray absorption spectroscopy (XAS). As confirmed, in the presence of silica, the pyrohydrolysis of CaCl2 commences from 800 °C, lower than the minimum temperature predicted based on the existing thermodynamic database. The attraction of Ca2+ by SiO44− breaks the Ca-Cl bond successfully. The addition of Mg2+ can also improve the HCl regeneration extent to nearly 100%. Upon the addition of Mg2+, a structure of Ca-O-Mg-Cl is very likely to form, in which the second coordination shell of Ca2+ is occupied by both Cl− and Mg2+. Consequently, the incorporated Mg2+ bonds with Cl−, “pushing” the Ca2+ in the third shell further away, leading to a distorted and less crystalline silicate matrix from which the liberation of Cl− is easier. The Cl K-edge XANES shows that the reaction residues feature a unique, long-range multi-scattering phenomenon; this differs from the fully molten Cl-bearing glasses that bear a high similarity with CaCl2.

Modern multi-color RGB micro-light emitting diode (μLED) displays and digital micro-mirror laser projectors often require the use of both III-V and III-Nitride material systems for different pixel/laser colors. This is due primarily to the conventionally low efficiencies of red emitters based on the InGaN materials system, which is used to create green and blue emitters for RGB displays. The main challenges for InGaN red emitters are the quantum confined stark effect (QCSE) and the difficulty of incorporating high In-content into the active region. In this work, InGaN/InGaN/delta-InN quantum wells (QWs) on InGaN substrates are proposed and demonstrated to show significant enhancement in electron-hole wavefunction overlap (Te_hh) and spontaneous emission radiative recombination rate (Rsp) in the red emission regime. Analysis of InGaN/InGaN/delta-InN QWs with InGaN barriers emitting at 630 nm was performed using a self-consistent six-band k · p formalism. The Γe_hh was shown to increase by more than 230% compared to an InGaN/InGaN QW emitting at 630 nm, leading to significant increases in Rsp and internal quantum efficiency (ηIQE). With growth of InN monolayers on InGaN now readily achievable, this novel active region design could pave the way for high-efficiency, native red-emitting InGaN LEDs and lasers.

Ameliorating the interfacial issues of the zinc anode, particularly dendrite growth and electrode corrosion, is imperative for rechargeable zinc metal batteries. Herein, an electrochemical-inert li...

The structural diversity and tunability of metal organic frameworks (MOFs) represent an ideal material platform for a variety of practical scenarios ranging from gas storage/separation to catalysis, yet their application in chemiresistive gas sensing is relatively lacking, due to the requirements of combined electrical conductivity and optimized gas adsorption properties. Here, we report an effective chemical sensing strategy based on missing-linker two-dimensional conductive MOF, with incorporated defects via a simple ligand oxidization method. The multiple hydroxyl defect sites in the conductive 2D missing-linker amorphous Ni-HAB (aNi-HAB) enable rapid adsorption and desorption of water molecules compared to crystalline Ni-HAB (cNi-HAB). As a result, the aNi-HAB sensory device shows good sensitivity, selectivity, linearity, fast response/recovery rate, and excellent stability, which can be further improved by Nafion functionalization. Theoretical investigations including transient current measurement, density functional theory (DFT) calculations, and systematic performance evaluation of isostructural 2D aM-HAB (M = Cu, Fe, Co) MOF showed that unique transport mechanism and adsorption/activation energies originated from hydrogen bonding at defective sites are critical for enhanced humidity response, and further confirmed that defect engineering through missing linker incorporation is a general and effective approach to tune the sensing properties of conductive MOF materials.

Ab initio calculations are used to understand the fundamental mechanism of the solid solution softening/hardening of the Mo-binary system. The results reveal that the Mo-Ti, Mo-Ta, Mo-Nb, and Mo-W interactions are primarily attractive with negative heats of formation, while the interactions of Mo-Re, and Mo-Zr would be mainly repulsive with positive heats of formation. It is also shown that the addition of Re and Zr would cause the solid solution softening of Mo by the decrease of the unstable stacking fault energy and the increase of ductility. On the contrary, the elements of W, Ta, Ti, and Nb could bring about the solid-solution hardening of Mo through the impediment of the slip of the dislocation and the decrease of ductility. Electronic structures indicate that the weaker/stronger chemical bonding due to the alloying elements should fundamentally induce the solid solution softening/hardening of Mo. The results are discussed and compared with available evidence in literatures, which could deepen the fundamental understanding of the solid solution softening/hardening of the binary metallic system.

A chitosan/deoxyribonucleic acid (CHI/DNA)5 coating was constructed by layer-by-layer (LbL) assembly dip coating method with Mg(OH)2 coating as an inner protective layer on AZ31 alloy. X-ray diffractometry, X-ray photoelectron spectrometry, Fourier transform infrared spectroscopy and field-emission scanning electron microscopy were utilized to represent the chemical compositions and surface morphologies of the coatings. Electrochemical tests and hydrogen evolution measurements were implemented to confirm the good corrosion resistance of the composite coating in artificial body fluid. Antimicrobial activity of the composite coatings was tested via the plate-counting method, and the cytotoxicity of the samples was appraised by MTT assay and Live/dead staining. A double action was put into effect for the composite coating, which the inner Mg(OH)2 coating plays the part of physical barrier, and the outer (CHI/DNA)5 coating is employed as an inducer to fabricate a biocompatible Ca-P corrosion product coating during immersion, making up for its thin thickness. Otherwise, the composite coating is also beneficial for the growth of bone, resulting from the biomineralization effect of the outer polyelectrolyte multilayer. The good antibacterial property of the (CHI/DNA)5/Mg(OH)2 coating is ascribed to the contact-killing strength of CHI. Thus, the obtained (CHI/DNA)5/Mg(OH)2 coating has a wide application prospect in the field of Mg-based bone implantation.

This article proposes that the lens of scale may potentially yield fresh insights into the comparative research on gentrification. First, the flows of capital, people, and knowledge in re-scaling furnish a point of departure for a holistic theory of planetary gentrification and a vital reference point for comparison. Second, to harness upscaling and downscaling in tandem, comparative studies should adequately connect gentrification with similar regional/local ontologies to obtain greater ontological power. The disadvantaged should take advantage of a loose and shifting alliance among the pro-gentrification forces to find a “real choice” (instead of a “perfect choice”) for those affected. Moreover, a pragmatic solution is opprobrium against predatory flows, particularly the flows of capital, whose nature is defined by local peculiarities.

In this work, six CoII coordination polymers (CPs) based on a new semi-rigid methylene-bridged bis-pyridyl-bis-amide ligand N,N′-bis(4-methylenepyridin-4-yl)-2,6-naphthalenedicarboxamide (4-bmpnd) and various polycarboxylates, namely [Co(4-bmpnd)(5-HMIP)2(H2O)2] (1), [Co2(4-bmpnd)2(5-NIP)2(H2O)]·2H2O (2), [Co2(4-bmpnd)(5-AIP)2(H2O)]·2H2O (3), [Co(4-bmpnd)0.5(1,4-CHDC)]·H2O (4), [Co(4-bmpnd)(1,4-NDC)(H2O)2]·2DMF (5), and [Co(4-bmpnd)(1,2,4,5-BTA)0.5(H2O)] (6) (5-H2MIP = 5-methylisophthalic acid, 5-H2NIP = 5-nitroisophthalic acid, 5-H2AIP = 5-aminoisophthalic acid, 1,4-H2CHDC = 1,4-cyclohexanedicarboxylic acid, 1,4-H2NDC = 1,4-naphthalenedicarboxylic acid, and H4BTA = 1,2,4,5-benzenetetracarboxylic acid) have been constructed by a hydrothermal/solvothermal method. Their structures are characterized by infrared spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction. CP 1 has a 1D linear structure. CP 2 displays a 2D 4-connected wave network. CP 3 exhibits a 2D sandwich-type structure. CP 4 can be described as a 4-connected 2D grid-like structure. CP 5 shows a 4-connected 3D cds framework with the topological symbol of {65·8}. CP 6 is a (4,4)-connected 3D framework with the {4·64·8}2{42·104} topology. The effects of functional groups and the number of the carboxyl groups of polycarboxylates on the structures of the title coordination polymers were discussed. The photocatalytic properties of CPs 1–6 were studied under UV irradiation, which have good photocatalytic degradation performance for anionic dye Congo red (CR). The possible photocatalytic mechanism was explored.