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A novel and facile strategy for fabricating red phosphorus@nitrogen doped graphene/carbon nanotube aerogel (P@NGCA) is proposed as a free-standing anode for high energy sodium-ion batteries. Owing to an optimized structure of red P uniformly confined in porous NGCA with high conductivity and mechanical stability, the free-standing P@NGCA anode exhibits outstanding sodium storage performance with a high areal capacity of 3.3 mA h cm−2 and superior initial Coulombic efficiency of 80%. [ABSTRACT FROM AUTHOR]

In this paper, two different pulse control methods are proposed to generate multi-butterfly attractors based on the Sprott C system. By introducing a bipolar multilevel pulse signal to the boostable variable z of the Sprott C system, translational multi-butterfly attractors with constant Lyapunov exponents can be obtained. Another method for generating nested multi-butterfly attractors is to replace the DC voltage of the Sprott C system with the unipolar multilevel pulse signal, and the dynamical behavior involves the superposition of multiple attractors corresponding to different pulse amplitudes. By defining time as an additional state variable, the proposed non-autonomous systems can be transformed into autonomous systems for analysis. It can be seen that systems have no equilibria, so they belong to hidden attractors. A normalized circuit implementation is given, translational and nested hidden multi-butterfly attractors can be obtained by setting proper pulse signals. Moreover, the number of butterflies can be adjusted by changing the number of pulse voltage sources without reconstructing nonlinear functions. Theoretical analysis and simulation results prove the effectiveness of these methods. [ABSTRACT FROM AUTHOR]

The g-C3N4-Pt photocatalyst was successfully prepared by the combination of a biosynthesis method and sol deposition, which were used for hydrogen evolution from water splitting. The layers of g-C3N4 are thinned and the Pt nanoparticles simultaneously become tightly bound to g-C3N4 by secondary calcination in the process of synthesizing the g-C3N4-Pt photocatalyst. Analysis of the morphological structure and instrumental characterization of the optical performance revealed that the Pt nanoparticles were successfully loaded and well dispersed on the surface of g-C3N4. Furthermore, the absorption wavelength range of the g-C3N4-Pt photocatalyst in visible light was widened and the absorption increased. The activity and photostability of the g-C3N4-Pt photocatalyst for hydrogen evolution under visible light irradiation (λ≥420 nm) were excellent. The rate of H2 evolution reached 582.4 μmol h−1 g−1, and the quantum efficiency (QE) reached 2.70% at 420 nm. [ABSTRACT FROM AUTHOR]

Numerous accidents of emulsion explosive (EE) are attributed to uncontrolled thermal decomposition of ammonium nitrate emulsion (ANE, the intermediate of EE) and EE in large scale. In order to study the thermal decomposition characteristics of ANE and EE in different scales, a large-scale test of modified vented pipe test (MVPT), and two laboratory-scale tests of differential scanning calorimeter (DSC) and accelerating rate calorimeter (ARC) were applied in the present study. The scale effect and water effect both play an important role in the thermal stability of ANE and EE. The measured decomposition temperatures of ANE and EE in MVPT are 146°C and 144°C, respectively, much lower than those in DSC and ARC. As the size of the same sample in DSC, ARC, and MVPT successively increases, the onset temperatures decrease. In the same test, the measured onset temperature value of ANE is higher than that of EE. The water composition of the sample stabilizes the sample. The large-scale test of MVPT can provide information for the real-life operations. The large-scale operations have more risks, and continuous overheating should be avoided. [ABSTRACT FROM AUTHOR]

Sodium chloride (NaCl) was added to the ammonium nitrate (AN) by different mixing methods. The heat sensitivity performance and the explosive performance of AN and ammonium nitrate fuel oil (ANFO) were studied by using differential scanning calorimeter (DSC), the UN gap test and Koenen test. The results show that: When AN contained 15 % (solution mixing) and 35 % (mechanical mixing) additive, AN maximum exothermic peak increased from 286.75 to 300.63 and 307.83 °C, respectively. For the mechanical mixing, the critical values of the UN gap test and Koenen test AN were 35 and 40 %. The ANFO both were 50 %; for the solution mixing, AN were 15 and 40 %, the critical value of the UN gap test, ANFO was 25 %. AN and ANFO contain more than the critical value of additive, the AN and ANFO would not be detonated. [ABSTRACT FROM AUTHOR]

Owing to the abundant resource and tunable structure, amorphous carbon materials have been widely studied as anode for alkali-metal ion batteries. However, it is still a huge space to promote their electrochemical performance for potassium ion batteries (PIBs), especially rate capability, because of the sluggish kinetics of potassium ions. In this work, 3D amorphous carbon with nitrogen and oxygen dual doping (N/O-3DC) is elaborately designed and facilely synthesized for high performance PIBs. Benefit from the synergistic effect of structural advantages, N/O-3DC electrode delivers a high reversible capacity (345 mA h g−1 at 0.03 A g−1), excellent rate performance (132 mA h g−1 at 9.6 A g−1) and ultralong lifespan (0.02% capacity decay per cycle over 1000 cycles at 3 A g−1). Combined with control experiment and structural characterization, it demonstrates the interaction between introduction of heteroatoms, construction of 3D open pore network and tailored microstructure, obtaining more active sites and enlarged interlayer spacing. Kinetic analysis and density functional theory calculations reveal dual N/O doping can not only facilitate the adsorption/desorption of K+ and elevate electronic conductivity, but also reduce energy barrier for K+ diffusion, hence promote the reaction kinetics. This work presents an appealing development of high performance carbon anode with multi-strategy coupling for PIBs. [Display omitted] • The N/O-3DC is obtained via a green approach originating from low-cost protein and facile NaCl template. • The structure design of N/O-3DC creates synergy effect for fast and stable potassium storage. • The N/O-3DC anode exhibits the superior rate performance. • The kinetic analysis and density functional theory calculations illuminate the electrochemical mechanism. [ABSTRACT FROM AUTHOR]

Fault diagnosis is crucial for reliability assessment of rotation machinery. Due to issues such as data privacy, it is impossible to get complete information for fault diagnosis in practical and challenging scenario. To solve aforementioned problem, fault diagnosis under partial information is studied. A source-free domain adaptation method for fault diagnosis, enabling cross-domain fault diagnosis without accessing the source data, is proposed. Firstly, multireceptive field graph convolutional(MRF-GCN) was used to aggregate different numbers of node information from different receptive fields for extracting more representative features. Secondly during the training process on the target domain, positive and negative pairs are constructed based on the samples' neighbors and extended neighbors. Clustering and domain adaptation are then performed using a contrastive loss. Finally, information maximization loss is employed to improve the diagnostic accuracy. Experimental results demonstrate that, the proposed approach achieves favorable diagnostic performance under partial information, even without access to source domain data. • A source-free domain adaptation(SFDA) method for fault diagnosis is proposed. • More representative features are extracted through graph convolutional. • Positive and negative pairs are constructed using the neighbors of samples. • SFDA is achieved by minimizing contrastive loss and information maximization loss. [ABSTRACT FROM AUTHOR]

This paper is concerned with the multistability of fractional-order competitive neural networks (FCNNs) with time-varying delays. Based on the division of state space, the equilibrium points (EPs) of FCNNs are given. Several sufficient conditions and criteria are proposed to ascertain the multiple O (t − α) -stability of delayed FCNNs. The O (t − α) -stability is the extension of Mittag-Leffler stability of fractional-order neural networks, which contains monostability and multistability. Moreover, the attraction basins of the stable EPs of FCNNs are estimated, which shows the attraction basins of the stable EPs can be larger than the divided subsets. These conditions and criteria supplement and improve the previous results. Finally, the results are illustrated by the simulation examples. [ABSTRACT FROM AUTHOR]

A novel design strategy for synthesizing hard carbon microspheres (HCMs) from a single source of sodium lignin sulfonate is proposed for a practical anode material of sodium-ion batteries. The HCM has an optimized microstructure, including an enlarged interlayer spacing and few defects, along with a low specific surface area. As an anode material of sodium-ion batteries, HCM is highly promising for practical applications because of its high capacity and reversibility. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effects of Clostridium butyricum addition to diets in late gestation and lactation on the reproductive performance and gut microbiota for sows. A total of 180 healthy Landrace × Yorkshire sows at 90 d of gestation were randomly assigned to one of four groups, with 45 replicates per group, receiving a basal commercial diet (Control, 0% C. butyricum) or diet added with 0.1% C. butyricum (1 × 108 CFU/kg of feed), 0.2% C. butyricum (2 × 108 CFU/kg of feed), 0.4% C. butyricum (4 × 108 CFU/kg of feed), respectively. The experiment was conducted from 90 d of gestation to weaning at 21 d of lactation. The results showed that the interval between piglet born was linearly (P < 0.05) decreased, and the duration of farrowing was significantly (quadratic, P < 0.05) shortened as C. butyricum addition increased. There was a linear (P < 0.05) increase in litter weight at weaning and litter weight gain. The concentrations of IgG and IgM in colostrum, and IgM in milk were linearly increased (P < 0.05) as C. butyricum addition. Serum MDA concentrations of sows at parturition and 14 d in lactation, and piglets at 14 and 21 d of age were linearly (P < 0.05) decreased, respectively. The serum total antioxidant capacity concentrations of sows at parturition and 14 and 21 d in lactation, and piglets at 14 and 21 d of age were linearly (P < 0.05) increased as C. butyricum addition, respectively. There was a linear decrease in the serum endotoxin concentration of sows on 21 d in lactation (P < 0.05). The serum cortisol concentrations of piglets at 14 and 21 d of age were both significantly (quadratic, P < 0.05) decreased. The 0.2% C. butyricum increased the relative abundance of Bacteroidetes (P = 0.016) at phylum level, Prevotellaceae_NK3B31_group , Prevotella_1 , Prevotellaceae_UCG-003 , Prevotella_9 , Alloprevotella (P < 0.05) at genus level, and decreased the relative abundance of Proteobacteria , Gemmatimonadetes , Actinobacteria (P < 0.001) at phylum level, and Clostridium_sensu_stricto_1 , Streptococcus , Escheruchia-Shigella , Sphingomonas , Succinivibrio (P < 0.05) at genus level and Firmicutes/Bacteroidetes ratio (P = 0.020). In conclusion, the present research indicated that dietary addition with C. butyricum could shorten the duration of farrowing and enhance the growth performance of suckling piglets. Moreover, 0.2% C. butyricum administration to sows changed the composition of intestinal microbiota, especially increased the relative abundance of Prevotella. [ABSTRACT FROM AUTHOR]

• Does not require pre-correction and additional images. • Insensitive to changes in height difference compared to the HT method. • Compared with the PHE method, there is no discretization error. Phase errors caused by the gamma nonlinear response of the phase shift profilometry (PSP) severely affect 3D measurement accuracy. To tackle this, a simple phase error compensation technique based on polar angle average is presented in this paper to improve the accuracy. Wrapped phase values are regarded as polar angles, and a polar axis distribution map can be obtained in the polar coordinate. Practically, the polar axis distribution (PAD) of the undistorted wrapped phase is uniform. When there are nonlinear effects in an PSP, the polar axis is unevenly distributed. The difference between adjacent polar angles is computed and then rearranged with specifically labels. After that, the even PAD diagram is generated, and the smooth phase can be further recovered. Compared with conventional nonlinearity correction methods, the proposed method corrects the error without any auxiliary conditions. Its effectiveness and robustness are verified in simulations and experiments. [ABSTRACT FROM AUTHOR]

The problem of Complex Modified Projective Synchronization (CMPS) for fractional-order complex-valued dynamic networks (FOCDNs) is investigated in this paper. Compared with real-valued dynamic networks, complex-valued dynamic networks have expansive application space. First, coupling weight has been generally considered as static constant in most situations, we consider time-varying coupling weight and the unknown parameters in the FOCDNs. Meanwhile, several parameter update laws are designed to estimate unknown parameters and an adaptive coupling weight is defined to adjust coupling nodes in order to solve CMPS problem of the network. Second, some effective criteria for CMPS of FOCDNs are derived by fractional calculus and Lyapunov stability theory. According to the theoretical analysis, FOCDNs with time-varying delay can achieve CMPS via adaptive controller. Finally, the effectiveness of the modified projective strategy for fractional-order complex networks is illustrated via two numerical examples in the complex-valued space. [ABSTRACT FROM AUTHOR]

Ammonium nitrate (AN) can decompose and further detonate under some conditions, e.g., in the presence of impurities which act as promoters. Its reactive hazards have been widely studied for several years. However, many large accidents involving AN still happened frequently in the recent years. It is found that, for accidents in storage or transportation, the thermal runaway is a major factor. The main objective of the research is to examine the effect of potassium chloride (KCl) on the thermal stability of AN under acidic conditions. The thermal stability of samples was investigated by differential scanning calorimetry (DSC), accelerating rate calorimetry (ARC), the Cook-off test and the Dewar test. The results indicate that KCl can significantly reduce the thermal stability of AN under acidic conditions. The catalytic effect of KCl on the decomposition of AN is limited without acidic conditions. The scale effect also is important factor to influence the thermal stability of AN. [ABSTRACT FROM AUTHOR]

In this paper, Ta 1-x Mo x N films with varying Mo contents were deposited by reactive magnetrons sputter in mixed Ar/N 2 atmospheres at 350 °C. It's discovered that Ta 1-x Mo x N films at x = 0.13–0.86 maintains a NaCl type (B1) structure and a strong (200) preferred orientation. Besides, as Mo contents grow, the residual stress of films is attenuated from −3.24 GPa to −1.49 GPa, and the hardness of films first increases and then decreases. Specifically, with a nearly balanced Ta and Mo content (x = 0.57), the Ta 1-x Mo x N film exhibits higher hardness (39.5 ± 1.2 GPa) and elastic modulus (359.3 ± 8.8 GPa), up by 53.1% and 26.8% compared with TaN, higher fracture toughness, scratch critical load (91.5 N) and elasticity (76.7%). The Ta 1-x Mo x N film with x = 0.57 obtains lower coefficient of friction (0.417), and higher wear resistance (wear rate: 1.9 × 10−7 mm3/N*m). In addition, the density of states (DOS) in XPS valence band spectra from Ta 1-x Mo x N films is shifted toward lower binding energy with more Mo contents. Accordingly, the stronger metallic characteristics and the solid solution strengthening effect endow the Ta 1-x Mo x N films at x = 0.57 with higher hardness and toughness. [ABSTRACT FROM AUTHOR]

To achieve both hard and tough, Ag atoms with various contents were doped in Ta–C films. The microstructure, mechanical and tribological properties of TaC–Ag films were investigated and the strengthening effect of minimal Ag atoms on TaC–Ag films were explored. When the Ag target power is 8 W (∼1.18 at.% Ag), TaC–Ag film present FCC Ta(Ag)C solid solution phase. With increasing Ag target power from 12 to 30 W (∼9.35 at.% Ag), Ag free phases are separated from Ta(Ag)C phase, which is responsible for the results that the hardness of TaC–Ag film firstly increase then decreases with the increases of Ag doping content. High hardness (H∼49.0 GPa) and toughness (K IC ∼2.2 MPa m1/2) is obtained from TaC–Ag8 film with the Ag target power of 8 W, while the hardness monotonically decreases to 9.8 GPa for TaC–Ag30 film with the target power of 30 W. The low wear rate of TaC–Ag8 film is attributed its high hardness and toughness, while the low friction coefficient (0.25) of TaC–Ag30 film is due to the lubrication of Ag phase and highly graphitized carbon. [ABSTRACT FROM AUTHOR]

In this paper, magnetron sputtering from TaB 2 and Mo stoichiometric targets is used to prepare AlB 2 ternary Ta 1-x Mo x B films. The films with various Mo contents were obtained by adjusting the Mo target powers. It was discovered that the contents of Mo have an obvious impact on the crystallinity and phase structure stability of Ta 1-x Mo x B films. When x = 0.43, the (001) and (002) orientation is improved, while stabler AlB 2 structure is maintained simultaneously. While increasing x to 0.59, the films show amorphous structure. Meanwhile, as Mo contents rise, the hardness of films first decreases and then increases, eventually drops a lot. The Ta 1-x Mo x B films with x = 0.44 exhibit the superhardness (H = 49.9 ± 1.5 GPa) and elastic modulus (E = 520 ± 4.7 GPa), which benefit from the structure of Transition-metal diboride (TMB 2) and solid solution strengthening effect. Alloying Mo can increase the Valence electron concentration (VEC) of films and therefore enhanced films toughness, higher fracture toughness (K IC = 1.13 MPa·m1/2) and elasticity (85.805%) were achieved when x = 0.44, the films showed better ability to resist plastic deformation even in 500 gf load. In addition, the Ta 0.56 Mo 0.44 B films obtain higher wear resistance (4.5 × 10−7 mm3/Nm) in air, but excess Mo atoms lead to deterioration of mechanical properties (H = 25.0 GPa、E = 240.0 Gpa for Mo90). Ta 1-x Mo x B ternary films with appropriate Mo content show a good potential as a hard protective coating. • Binary TaB x films exhibits high hardness (62.24 GPa) accompanied with high brittleness (18.3 × 10−7 mm3/Nm). • TaB 2 and Mo target were used for the deposition of ternary borides AlB 2 Ta 1-x Mo x B. • The content and existence form of Mo were controlled by adjusting Mo target power. • Sustained superhardness (49.9 GPa)、improved toughness and sound wear rate (4.5 × 10−7 mm3/Nm) could be achieved by proper Mo addition. • Alloying excess Mo resulted in deterioration of mechanical properties. [ABSTRACT FROM AUTHOR]

The firing patterns of each bursting neuron are different because of the heterogeneity, which may be derived from the different parameters or external drives of the same kind of neurons, or even neurons with different functions. In this paper, the different electromagnetic effects produced by two fractional-order memristive (FOM) Hindmarsh–Rose (HR) neuron models are selected for characterizing different firing patterns of heterogeneous neurons. Meanwhile, a fractional-order memristor-coupled heterogeneous memristive HR neural network is constructed via coupling these two heterogeneous FOM HR neuron models, which has not been reported in the adjacent neuron models with memristor coupling. With the study of initial-depending bifurcation behaviors of the system, it is found that the system exhibits abundant hidden firing patterns, such as periods with different topologies, quasiperiodic firings, chaos with different topologies, and even hyperchaotic firings. Particularly, the hidden hyperchaotic firings are perfectly detected by two-dimensional Lyapunov stability graphs in the two-parameter space. Meanwhile, the hidden coexisting firing patterns of the system are excited from two scattered attraction domains, which can be confirmed from the local attraction basins. Furthermore, the color image encryption based on the system and the DNA approach owns great keyspace and a good encryption effect. Finally, the digital implementations based on Advanced RISC Machine are in good coincidence with numerical simulations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The influence of C/N dual-doping in MoS 2 based sputtered films was investigated. • The lamellar structure of MoS 2 was maintained with high doping level and low S/Mo. • The balance between mechanical properties and lubricating performance was achieved by adjusting the content of C/N dopants. Transition metal dichalcogenides (TMDs) show poor mechanical properties and weak corrosion and oxidation resistance in ambient atmosphere, which results in the limit application and the lower work life. Doping TMDs based films with the enhanced performance show the potential to apply in harsh environment. The C/N dual-doping Mo-S-C-N films were deposited by magnetron sputtering, and the evolution of alternative microstructure composed of TMDs phase and amorphous inclusions was analyzed. The enhancement on mechanical, tribological and anti-corrosion properties of films with C/N dual-doping were evaluated. The strengthened TMDs phase and inclusions with MoC x /MoN x hard phase result in the improvement of mechanical properties (hardness 8.57–19.09 GPa). The superior tribological performance was obtained from film with 10.67 at. % of C and 17.36 at. % of N (wear rate 8.24 × 10-7 mm3/Nm, average friction coefficient (CoF) 0.188) and film with 14.87 at. % of C and 15.02 at. % of N (wear rate 8.02 × 10-7 mm3/Nm, average CoF 0.166). The balance between the effect of lubricating phase and mechanical performance strengthen by C/N dopants were achieved in these two films. The passivation of reactive sites in MoS 2 leads to the improvement of corrosion resistance, while excessive dopants induce more pathways for corrosive medium, which leads to the corrosion failure of films. [ABSTRACT FROM AUTHOR]

Transition metal boride (TMB x) show the potential application as protective films at extreme environment due to their high hardness, but their low toughness limits reliability. In order to achieve both excellent mechanical and high wear resistances of the films, the microstructure of TaB x films deposited by magnetron sputtering were regulated by varing the substrate bias voltages. With the increase of the higher bias voltage, the B content of TaB x films decreases and the crystallinity of the TaB x films is enhanced. Meanwhile, the microstructure of TaBx films transforms from fibrous to dense columnar and then to granular structure with the increase of the bias voltage. The hardness and elastic modulue decrease then increase when the substrate bias voltage increases from 0 V to −240 V. The films exhibit a super high hardness of 86.07 GPa at the bias voltage increases of −180 V. The dislocation motion inhibited by the lattice defects lead to the super high hardness and a mild fracture toughness (K IC = 1.20 MPa m1/2). For the high hardness and relatively moderate fracture toughness, the TaB x film deposited at a bias voltage of −180 V show a lower wear rate (∼1.86 × 10−6, ∼5.22 × 10−6 mm3/Nm) at room temperature and 600 °C. Meanwhile, the hardness (77.5GPa) and thermal stability of −180 V films were mantained after annealing. • The bias voltage indeed effects on the crystallinity and microstructure of the films. • Unexcpected hardness (86.07 GPa) was achieved due to denser structure, lattice distortion and defect structure. • Improved hardness and toughness provided a sound wear resistance (1.83 × 10−6 mm3/Nm) for the TaB x films (−180 V). • The high hardness (77.5 GPa) and thermal stability of −180 V films were maintained after 600 °C annealing. [ABSTRACT FROM AUTHOR]

Alloying with other TMs (transition metals) is an effective strategy for hardening and toughening binary TMNs (transition metal nitrides) films. In this study, Ta 1-x W x N (x = 0–1) films with different W content were prepared by DC magnetron sputtering. The influences of W content on the microstructure and mechanical properties of Ta 1-x W x N films were investigated. The tribological behaviors of films from room temperature (RT) to 500 °C were measured. The Ta 1-x W x N films maintain a B1-NaCl structure in a range of x = 0–1. The roughness and grain size increase with raising W content. The hardness of Ta 1-x W x N films reaches a maximum value of 44.2 GPa at x = 0.39. The fracture toughness (K IC) achieves 4.47 MPa·m1/2 at x = 0.57, corresponding to the higher H/E (0.158) and H3/E2 (1.06 GPa). The Ta 0.24 W 0.76 N film shows lower friction coefficient (∼0.5) and wear rates (1.5–4.1 × 10−6 mm3/N·m) from RT to 500 °C. The tribological properties of Ta 1-x W x N films at room temperatures are directly relate to the H/E and H3/E2, while the tribological properties at 500 °C are mainly determined by the lubricious oxide films induced by tribo-reaction. • Hardness (42–44 GPa) and K IC (3.85–4.47 MPa·m1/2) were achieved when x = 0.39–0.76. • Ta 0.24 W 0.76 N films show good tribological properties in a wide temperature range. • Tribological properties are related to the tribo-reaction product oxides at 500 °C. [ABSTRACT FROM AUTHOR]

Ternary transition metal nitrides (TMNs) films with B1 structure (NaCl type) have been widely explored as hard protective materials. Their structure and mechanical performances are influenced by the stoichiometric coefficients (TM: N), while the films with high hardness yet sound toughness could be obtained by regulating the nitrogen content. In this case for the sub-stoichiometric B1 Ta-Mo-N x films, the microstructure, mechanical properties and the toughening mechanisms by N atoms were investigated. The NaCl-structure sub-stoichiometric Ta 0.44 Mo 0.56 N x films with N concentrations at 0.42 ≤x ≤ 0.73 grown by reactive magnetron sputter deposition. The film with x = 0.59 shows higher hardness (∼36.4 GPa), combined with shorter cracks around indentation and higher scratch resistance, reveals the enhanced fracture toughness (K IC =∼1.67 MPa*m1/2, H/E = 0.14); the film simultaneously obtained a lower wear rate (∼6.6 × 10−7 mm3/N * m) and friction coefficient (∼0.4). The formed point defects in sub-stoichiometric Ta-Mo-N x films are responsible for the enhanced toughness, while the film with x = 0.59 exhibit an increased p (N) - d-e g (Me) strength character accompanied with high d-t 2 g (Me) - d-t 2 g (Me) metallic states for the TM-N bonds according to the XPS results. • Ta-Mo-N x films with x = 0.42–0.73 are FCC single phase solid-solution. • The H and E of Ta-Mo-N x films can be monitored by controlling the N. • The films with sub-stoichiometric show high populated d-t 2 g metallic state. • The film with x = 0.59 shows high H (36.4 GPa), H/E (0.14) and H3/E2 (0.74 GPa). • Low wear rate of ∼6.6 × 10−7 mm3/N * m is obtained from Ta 0.44 Mo 0.56 N 0.59 film. [ABSTRACT FROM AUTHOR]

Ceramic-Ag films with enhanced mechanical and tribological properties have been widely researched. Transition metal nitrides (TMNs) films as hard ceramic material with doping Ag atoms commonly show a nano-composite structure and possess the combination of high hardness and toughness. Herein, the TaN film with incorporating few Ag atoms (1.2 at.%) presents FCC solid solution structure according to the HRTEM and XPS results, accompanied by grain refinement. From the XPS valence band and HRTEM, the increased metallic characters in electronic structure of TM-N bonds and the decreased grain size results in the enhanced mechanical properties. The TaN-Ag film with solid-solution structure possesses higher hardness (36.1 GPa) and toughness (K IC = 1.48 MPa*m1/2), combined with an improved wear resistance (wear rate: ∼1.9 × 10−6 mm3/N*m). In addition, a relatively lower coefficient of friction (0.18–0.23) is achieved for TaN-Ag films from the lubrication of AgTaO 3 activated by Ag atoms. • TaN-Ag film with doping 1.2 at.% Ag possess solid-solution structure. • TaN-Ag film with solute Ag shows enhanced metallic and strength character. • TaN-1.2 at.% Ag film obtains higher H (36.1 GPa), H/E (0.107) and H3/E2 (0.413 GPa). • Low wear rate of 1.9 × 10−6 mm3/N*m is obtained for TaN-1.2 at.% Ag film. • TaN-Ag films possess low Cof by the AgTaO 3 activated from self-oxidation of Ag. [ABSTRACT FROM AUTHOR]

Wear resistance and anti-oxidization are required for the binary transitional metal nitride coatings when they are applied as protective coating on cutting tools. The dope with other transitional metal elements is one of the effective strategies to enhance the wear resistance of binary transitional metal nitride coatings. In this study, Hf 1-x W x N ternary coatings with various W content were prepared by DC magnetron sputtering. The hardness, toughness and tribological properties of Hf 1-x W x N coatings varied with W doping amounts were investigated. The results show that the Hf 1-x W x N coatings with the x range of 0–1 maintain B1 structure (FCC single solid solution phase). High hardness (35.3 GPa) and enhanced toughness (3.5 MPa m1/2) are obtained from Hf 1-x W x N coating with x = 0.73 (Hf 0.27 W 0.73 N). The friction coefficient and wear rate of Hf 0.27 W 0.73 N are as low as 0.38 and 2.48 × 10−6 mm3/Nm at room temperature, while they are 0.42 and 8.12 × 10−6 mm3/Nm at the temperature of 400 °C. The excellent friction and wear properties of Hf 1-x W x N coatings at elevated temperatures are mainly attributed to the enhanced mechanical properties and the lubrication of tungsten oxides (WO 3). The balance between oxidation and tribological behaviors of Hf 1-x W x N coatings are achieved by optimizing W content. • Hf 1-x W x N films with x = 0–1 are FCC structure with single phase solid-solution. • Hf 0.27 W 0.73 N film maintained the better mechanical properties (K IC 3.5 MPa m1/2). • The tribological properties of Hf 1-x W x N films at RT were controlled by the H/E. • The lubrication WO x and B1 structure improved the film wear resistance at 400-600 °C. • Low wear rate of 2.48 and 8.12 × 10−6 mm3/Nm obtained at x = 0.73 under RT and 400 °C. [ABSTRACT FROM AUTHOR]

Ischemia heart disease, one of the lethal cardiovascular diseases, irreversibly impairs cardiac function and is recognized as the primary risk factor for mortality in industrialized countries. The myocardial ischemia treatment still faces a considerable degree of increasing unmet needs. Isosteviol sodium (STVNa) and its derivatives have been proven to effectively alleviate metabolic diseases, hypertension, and heart hypertrophy. Little is known about how STVNa confers the cardioprotective effect during acute myocardial ischemia (AMI). In the present study, a rat model of acute ST-segment–elevation myocardial ischemia by left anterior descending (LAD) ligation was established. Compared to the AMI model group, STVNa administration (4 mg/kg, twice a day) well preserved left ventricle function by ejection fraction (45.10 ± 10.39 vs. 73.64 ± 13.15, p = 0.0013) and fractional shortening (22.94 ± 6.28 vs. 44.00 ± 11.05, p = 0.0017). Further analysis shows that high-dose STVNa (4 mg/kg) significantly improved the hemodynamics in AMI rats, with LVSP (88.25 ± 12.78 vs 99.75 ± 5.10, p = 0.018), max dP/dt (2978.45 ± 832.46 vs 4048.56 ± 827.23, p = 0.096), LVEDP (19.88 ± 2.00 vs 22.26 ± 3.21, p = 0.04) and left ventricular relaxation time constant (Tau) (0.030 ± 0.006 vs 0.021 ± 0.004, p = 0.021). Mechanically, STVNa administration retained the myocardial levels of phosphorylated AMPK, and CPT1b. Moreover, STVNa significantly increased the total energy expenditure, and reduced fatty acid accumulation through mitochondrial oxidative phosphorylation, which was supported by the indirect calorimetry and cellular energy analysis. Taken together, these findings suggest that STVNa is a potential cardioprotection agent for ischemic cardiomyopathy, likely through improving energy homeostasis, left ventricular hemodynamics, and heart function. [Display omitted] [ABSTRACT FROM AUTHOR]

δ-TaN x films with different stoichiometry were deposited by DC magnetron sputtering on Si (100) substrate. Their microstructures and compositions were investigated by XRD, XPS, Raman and HRTEM. The hardness (H), elastic modulus (E), fracture toughness and tribological properties of films were evaluated by the ultra-micro indentation and a ball-on-disk tribometer. The correlation between H/E, H3/E2 and wear rate was discussed. As indicated by the results, the H, toughness of δ-TaN x films can be modified by controlling the variation of stoichiometric (N/Ta ratio). The H decreases from 39.5 to 24.7 GPa with N/Ta ratio increasing from 0.95 to 1.21. Meanwhile, the wear resistance deteriorates with the increase of N/Ta ratio. The film with a sub-stoichiometric shows a higher H/E, H3/E2, a better resistance of cracking and an improved wear resistance. Sound mechanical properties such as high hardness (H ~ 39.5 GPa), toughness (H/E ~ 0.12), resistance to cracking, lower wear rate (4.6 × 10−6 mm3/Nm) are simultaneously obtained from δ-TaN 0.95 film. • Polycrystalline δ-TaN x films with x = 0.95–1.21 were deposited by DCMS. • H and E can be monitored by controlling the stoichiometric of N/Ta. • H/E, H3/E2 and fracture toughness show similar variation tendency. • Low wear rate of 4.59 × 10−6 mm3/Nm is obtained from TaN 0.95 film with higher H/E. [ABSTRACT FROM AUTHOR]

The hardness and toughness of HfN films alloying with Ta element is crucial for their wear resistance when they are applied in the harsh environment. In this study, Ta x Hf 1−x N (x = 0–1) thin films with various Ta contents were deposited on silicon wafer and TC4 alloy substrates by DC reactive magnetron sputtering, respectively. The relationship between structure, mechanical and tribological properties of Ta x Hf 1−x N films was investigated. Ta x Hf 1−x N films are presented as the solid solutions with B1-NaCl rock salt structure. As the content of tantalum increases, the grain size and residual compressive stress of Ta x Hf 1−x N films increases firstly then decreases, while the preferred orientation transfers from (111) to (200) and then back to (111). The hardness and H/E increases initially and then decreases with the Ta contents, which is also consistent with the fracture toughness. When x is 0.58, Ta x Hf 1−x N film shows the maximum hardness value (44 GPa), H/E (0.15), H3/E2 (1.02 GPa), fracture toughness (3.48 MPa·m1/2) and lower wear rate (5.6 × 10−6 mm3/Nm). It is found that the wear resistance of Ta x Hf 1−x N films is directly related to the H/E and fracture toughness. • The toughness of Ta x Hf 1−x N films can be tuned by various Ta contents. • Higher hardness (44 GPa) and K IC (3.48 MPa·m1/2) were achieved in Ta 0.58 Hf 0.42 N. • Tribological properties of Ta Hf N films proportional to H/E and fracture toughness. [ABSTRACT FROM AUTHOR]

Hf-Mo-Si-N films with a series of Si contents were prepared by magnetron sputtering in a mixed Ar/N 2 atmosphere. Microstructure and surface morphologies of films were characterized by XRD, XPS, TEM and AFM. Besides, mechanical and tribological properties were evaluated. With increasing of Si addition, the phase of films transforms from single fcc Hf-Mo-N to nanocomposite structure consisted of Hf-Mo-Si-N crystalline and amorphous Si 3 N 4 phases. The Hf-Mo-Si-N film with 5.4 at.% Si content exhibits improved hardness of 38.6 GPa and enhanced toughness of 3.6 MPa·m1/2, which is ascribed to the synergistic effect of the solid solution strengthen, fine grains and interface strengthening in nanocomposite system. The precipitated amorphous Si 3 N 4 phase could hinder the cracks propagation, which results in higher fracture toughness. The low average friction coefficient of 0.37 and wear rate of 1.8 × 10−6 mm3/N are obtained from the Hf-Mo-Si-N film with 5.4 at.% Si, which is also accompanied with high value of H/E (0.14) and H3/E*2 (0.61 GPa). • Quaternary Hf-Mo-Si-N films were synthesized by DC and RF magnetron co-sputtering. • Hard yet tough nanocomposite films with dispersed a-Si 3 N 4 phases can resist crack propagation. • The proper Si-addition greatly improves tribological properties of films. [ABSTRACT FROM AUTHOR]

• 9 feed ingredients soluble and insoluble dietary fibers were separated for in vitro fermentation with sow faecal inoculum. • The capacity of SCFA, BCFA and ammonia produced by SDF were significantly higher than that of IDF. • Beet pulp have a better potential to be used in sow feed. • Fiber structure and composition may affect microbiota composition and ultimately affect fermentation characteristics. An in vitro-in vivo methodology was used to evaluate the potential value of different sources of fiber for gestation sows. Soluble and insoluble dietary fiber of 9 feed ingredients were isolated and fermented in vitro with sow faecal inoculum, using the cumulative gas production technique, to examine the kinetics, end-products and microbiota of fermentation after 72 h. It was shown that all fermentation kinetics parameters of gas production varied among feed ingredients. The production of short chain fatty acids (SCFA), branched-chain fatty acids (BCFA) and ammonia (NH 3) were greater for wheat grain and maize compared to other feed ingredients on insoluble dietary fiber (IDF) fermentation for 36 h, and higher for maize compared to other feedstuffs on IDF fermentation for 72 h. However, SCFA, BCFA and NH 3 were the highest of sorghum grain compared to other feedstuffs on soluble dietary fiber (SDF) fermentation for 36 and 72 h. The capacity of SCFA, BCFA and NH 3 produced by SDF were significantly greater than that of IDF from different ingredients. IDF and SDF of beet pulp exhibited lower pH, higher Bacteroidetes and lower Firmicutes phylum after fermentation. The observed species and Shannon index in the beet pulp IDF and SDF were significantly lower than others. In genus level, Parabacteroides and unidentified_Prevotellaceae were higher but unidentified_Lachnospiraceae was lower in SDF fermentation compared to IDF fermentation. Further, a total of 75 multiparous gestation sows (Landrace × Yorkshire) were randomly assigned three fiber-rich diets provided by beet pulp (BP), soybean hull (SH), and wheat bran (WB) after mating. The sows were fed with three different fiber diets during gestation, but all the sows were similarly fed ad libitum during lactation. Sows fed BP diets farrowed a greater number of total (+1.7 pigs, P <0.05) and alive (+1.1 pigs, P <0.1) piglets compared with sows fed SH diets. In summary, beet pulp, irrespective of fiber type maybe have a better potential to be used in sow nutrition to manipulate the fermentation activity, microbiota and a greater litter size. Moreover, IDF and SDF from different feed ingredients, as well as the same feedstuff IDF and SDF, due to differences in fiber structure and composition may affect microbiota composition and ultimately affect the level of fermentation metabolites produced. [ABSTRACT FROM AUTHOR]

In order to achieve hard, tough and super wear resistant film, Ta 1-x W x C y films with various W contents were deposited by DC magnetron sputtering and their structural evolution and mechanical properties were investigated. Ta 1-x W x C y films show the structures of fcc-NaCl solid solution and nanocomposite, which depended on the W contents. Doping W atoms induces the amorphous carbon (a-C) precipitated at the grain boundary. The structure of Ta 1-x W x C y film changes from the single solid solution to a nanocomposite structure, which consists of Ta(W)C nanocrystalline with C vacancies and small amount of a-C. Ta 0.69 W 0.31 C 0.75 film shows superior mechanical properties with ultra-high hardness of 43.9 GPa and enhanced toughness (K IC) of 3.95 MPa·m1/2, which is attributed to the synergistic effect of solid solution strengthening, composite structure strengthening and toughening related to the interaction of valence electrons. Both low average friction coefficient of 0.28 and wear rate of 1.12 × 10−6 mm3/N·m is obtained from the Ta 0.69 W 0.31 C 0.75 film, which is consistent well with its super mechanical properties. In this study, the fracture toughness is not directional related to H/E and H3/E2 for the nanocomposite coating. • Doping W atoms triggers the decarburization of TaC to form nanocomposite structure. • The Ta 0.69 W 0.31 C 0.75 film obtains super hardness (43.9 GPa) and K IC (3.95 MPa·m1/2). • The tribological properties of Ta 1-x W x C y films depend on the mechanical properties. • The H/E (and H3/E2) is not proportional to fracture toughness. [ABSTRACT FROM AUTHOR]

Alloying elements in binary nitride is considered as a promising method to design hard and tough films. Hf atoms are proposed to be incorporated in CrN nitrid films to form ternary nitrides, which may possess the improved mechanical and tribological properties. In this study, Cr 1-x Hf x N [x = Hf/(Cr + Hf)] films were sputtering deposited by incorporating Hf into CrN film in an mixed atmosphere of Ar and N 2. The influences of Hf addition on the microstructure, mechanical and tribological properties of Cr 1-x Hf x N films were investigated. The results show that the hardness and fracture toughness of CrN film is significantly improved due to solid solution strengthening by incorporating Hf atoms. Thanks to the improved hardness and toughness, the wear resistance of CrN film is enhanced. A high H/E and H3/E2 values, which are regarded as the reflection of toughness of hard films, are obtained from Cr 0.69 Hf 0.31 N film with higher hardness (30.49 GPa). The lowest wear rate of about 1.03 × 10−6 mm3/Nm is also presented for Cr 0.69 Hf 0.31 N film, which corresponds to higher H/E(~0.125) and H3/E2(~0.481 GPa). • Cr 1-x Hf x N films were firstly prepared by dc reactive magnetron sputtering. • Cr 0.69 Hf 0.31 N film obtained optimal mechanical and tribological properties. • H/E and H3/E2 are reverse linearly proportional to wear rate for Cr 1-x Hf x N film. • Scratch behavior shows similar variation tendency with toughness. [ABSTRACT FROM AUTHOR]