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Background: Anti‐PD1/PD‐L1 antibody plus human epidermal growth factor receptor 2 (HER2) antibody and chemotherapy have become the new first‐line therapy for HER2 overexpression‐positive advanced gastric cancers (GC), suggesting that HER2 and PD‐L1 play a vital role in guiding systemic treatment for patients with GC. This study aimed to depict the genomic and immune landscapes of Chinese patients with GC and investigate their correlations with HER2 amplification and PD‐L1 expression. Patients and Methods: Next‐generation targeted sequencing and PD‐L1 immunohistochemistry were performed on tumor samples from 735 patients with pathologically diagnosed GC. The genomic and immune landscapes and their correlations with HER2 amplification and PD‐L1 expression were analyzed. Results: The most commonly mutated genes in Chinese GC were TP53 (64%), CDH1 (20%), ARID1A (18%), HMCN1 (15%), KMT2D (11%), and PIK3CA (11%). Seventy‐six (10%) patients were HER2 amplification, and 291 (40%) had positive PD‐L1 expression. Classifying the total population based on HER2 amplification and PD‐L1 expression level, 735 patients were divided into four subgroups: HER2+/PD‐L1+ (4.5%), HER2+/PD‐L1− (5.9%), HER2−/PD‐L1+ (35.1%), and HER2−/PD‐L1− (54.5%). The HER2+/PD‐L1− and HER2+/PD‐L1+ subgroups exhibited dramatically higher rate of TP53 mutations, CCNE1 and VEGF amplifications. The HER2+/PD‐L1− subgroup also had a markedly higher rate of MYC amplification and KRAS mutations. The HER2−/PD‐L1+ subgroup had significantly higher rate of PIK3CA mutations. HER2+/PD‐L1− subgroup had the highest TMB level and HER2−/PD‐L1+ subgroup had the highest proportion of patients with microsatellite instability‐high than other subgroups. Furthermore, we observed that different HER2 amplification levels had distinct impacts on the correlations between PD‐L1 expression and therapeutic genomic alterations, but no impact on the prognosis. Conclusion: The combination of HER2 amplification and PD‐L1 expression in Chinese patients with GC could stratify the total populations into several subgroups with distinctive genomic and immune landscapes, which should be considered when making personalized treatment decisions. [ABSTRACT FROM AUTHOR]

The expansion of online social networks has led to attracting a significant number of users. Meanwhile, the analysis of these networks has raised new perspectives and challenges due to the large amount of information. One of these challenges in the analysis of social networks is the problem of link prediction. The purpose of this problem is to find links that have not yet been observed, but may exist in the future. There are many solutions for link prediction on monoplex networks. However, many real social networks model communication in multiple layers. In recent years, link prediction in multilayer social networks has attracted the attention of many researchers. A solution for multilayer networks involves taking into account the information of all layers to make predictions for a target layer. Among the link prediction techniques based on monoplex networks, local random walk is very popular. This paper presents an extended version of this technique for multilayer social networks considering reliable routes and weighted links. Our proposed algorithm as Weighted Reliable Local Random Walk (WRLRW) simultaneously uses interlayer and intralayer information to predict links in a target layer of a multilayer network. WRLRW adjusts link weights based on multimodal and topological features and forms reliable routes between users by multiplying link weights. We demonstrated the effectiveness of WRLRW to address the link prediction problem on real-world multilayer networks through numerical simulations. WRLRW has better performance compared to link prediction techniques based on monoplex networks as well as state-of-the-art methods based on multilayer networks. According to the results of the experiments, WRLRW obtains 3.2% and 2.5% better average f-measure compared to SEM-Path (Structural, Ego-Paths and Meta-Paths features) and MLRW (Multiplex Local Random Walk), respectively. [ABSTRACT FROM AUTHOR]

In this work, nominal composition (1-x)BaTiO 3 -xBi(Zn 0.5 Y 0.5)O 2.75 [abbreviated as (1-x)BT-xBZY, (x = 0.05, 0.1, 0.15, 0.2, 0.25)] ceramics were prepared by solid-state reaction method, and sintered in reducing atmosphere. Effect of introducing BZY on the structure, dielectric and insulating properties of BT was investigated. XRD results demonstrated that the unit cell volume of (1-x)BT-xBZY ceramics expanded with the addition of BZY, accompanied with the transformation from tetragonal to pseudo-cubic phase when x ≥ 0.05. Electrical properties measurement showed that the dielectric-temperature stability and insulating properties of (1-x)BT-xBZY ceramics were effectively improved by BZY addition, where the optimum performances were achieved at x = 0.15, with the dielectric constant of 1362 and dielectric loss of 1.4%, and resistivity of 5.5 × 1012 Ω cm at room temperature, meeting the standard of X8R specification for MLCC application. The feasible mechanism of improved anti-reduction properties for (1-x)BT-xBZY ceramics was investigated by employing X-ray photoelectron spectra (XPS) and thermally stimulated depolarization current (TSDC) testing techniques, where the formation of defect dipoles [2Y Ti ˈ - V O.. ] and the deoxidation of Bi ion were revealed and considered to be responsible for the anti-reduction behavior. • (1-x)BT-xBZY ceramics were sintered in reducing atmosphere. • X8R ceramics with excellent insulation performances were achieved. • Anti-reduction mechanism were comprehensively investigated. • Defect structures inside the ceramic were identified. • Defective dipoles beneficial to the anti-reduction properties of BT-BZY ceramics. [ABSTRACT FROM AUTHOR]

Combining in situ high-pressure X-rayscattering with transmissionelectron microscopy, we investigated the pressure-induced structuralswitches between the rock salt and amorphous phases as well as theassociated mechanisms of their crystallization and growth in 6 nmPbTe nanocrystal. It was observed that rock salt PbTe nanocrystalstarted to become amorphous above 10 GPa and then underwent a low-to-highdensity amorphous phase transformation at pressures over 15 GPa. Thelow-density amorphous phase exhibited a structural memory of the rocksalt phase, as manifested by a backward transformation to the rocksalt phase via single nucleation inside each nanoparticle upon therelease of pressure. In contrast, the high-density amorphous phaseremained stable and could be preserved at ambient conditions. In addition,electron beam-induced heating could drive a recrystallization of therock salt phase on the recovered amorphous nanoparticles. These studiesprovide significant insights into structural mechanisms for pressure-inducedswitching between amorphous and crystalline phases as well as theirassociated growth processes. [ABSTRACT FROM AUTHOR]

Highlights: [•] ZrO2 nanotubes with different diameters were prepared by anodization. [•] The photoluminescence properties of the as-prepared ZrO2 nanotubes and that annealed at 400°C were tested. [•] The photocatalytic properties of ZrO2 nanotubes were presented. [ABSTRACT FROM AUTHOR]

Abstract: Shape memory alloy In–21at.% Tl nanowires were prepared by a mechanical injection method. Transmission electron microscopy observations revealed that the nanowires are composed of polycrystals. At room temperature, the nanowires were characterized as martensite with dense twins, and the twining plane was identified as {101} of the face-centered tetragonal structure. The nanowire growth direction was found to be primarily along <110>. By in situ heating, reversible phase transformations between the martensite and the parent phase were observed. [Copyright &y& Elsevier]

Abstract: The thermal stability of functionalized carbon nanotubes (CNTs) has been studied experimentally by direct in situ observations using a heating stage in a transmission electron microscope, from room temperature (RT) to about 1000°C. It was found that the thermal stability of the functionalized CNTs was significantly reduced during the in situ heating process. Their average diameter dramatically expanded from RT to about 500°C, and then tended to be stable until about 1000°C. The X-ray energy dispersive spectroscopy analysis suggested that the diameter expansion was associated with coalescence of the carbon structure instead of deposition with additional foreign elements during the heating process. [Copyright &y& Elsevier]

Abstract: In order to prepare visible-light responsive iodine-doped TiO2, a new facile synthetic approach was proposed, which started with the cost-efficient and environmentally friendly precursor of undoped anatase TiO2 to form nanotube structures as templates that collapsed and recrystallized into I-TiO2 nanopowders in HIO3 solution, followed by annealing at different temperatures. The modification of TiO2 to incorporate iodine and form titanium dioxide with significantly enhanced absorption in the visible range of the spectrum was investigated. The extent of iodine dopant incorporation was determined by X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray analysis (EDX) and was found to be homogenously distributed on each nanostructure as determined by electron energy-loss spectroscopy (EELS) elemental mapping and EDX spectroscopy. The modified TiO2 exhibits a dramatically extended absorption edge beyond 800nm as compared to the original and unmodified TiO2. [Copyright &y& Elsevier]

Abstract: During the in-situ order–disorder transition of intermetallic L12-type Au3Fe1−x nanocrystals, structural information has been retrieved from their electron diffraction patterns based on the Pawley refinement that is unrelated to the electron kinematical or dynamical scattering nature as well as the Rietveld refinement using a kinematical approximation. At room temperature, it was found that the nanocrystals contain approximately x=40% vacancies at the Fe site. Based on in-situ heating this phase displayed an irreversible order–disorder transition, with the transition temperature between 553 and 593K. A sudden increase in lattice parameter was detected during the first heating from the ordered phase, while the second heating of the disordered phase showed only a linear relationship with temperature. From the lattice parameter measurement of the disordered phase, the coefficient of thermal expansion was estimated as 1.462×10−5 K−1. The long-range order parameter S was determined by the refined site occupancies, as well as the integrated intensities of the superlattice (100) and fundamental (220) reflections using the Pawley and Rietveld refinements during the order–disorder transition. Considering the dynamical scattering effect, Blackman two-beam approximation theory was applied to corrected S, which slightly attenuated after the correction. A comparison of the electron diffraction with X-ray diffraction data was made. It was demonstrated that elemental and structural information could be retrieved through quantitative electron diffraction studies of the nanomaterials. Since the Pawley refinement algorithm does not include the electron scattering event, it is especially useful to refine the electron diffraction data regardless of the sample thickness. [Copyright &y& Elsevier]

Abstract: CaZnGe2O6:Tb3+ afterglow phosphors were prepared by solid state reaction using organic coated ZnO nanopowders and their photoluminescence, X-ray luminescence and afterglow properties were investigated. The CaZnGe2O6:Tb3+ samples emit a green luminescence at 548nm attributed to the 5D4–7F5 transition of Tb3+. It was observed that the replacement of bulk ZnO by ZnO nanopowder in the sample synthesis increases the luminescence intensity. By adjusting the mass ratio of bulk ZnO to nanopowder ZnO, the photoluminescence intensity, X-ray luminescence intensity, and afterglow efficiency are improved. The optimized sample made with a 0.71ratio of nano ZnO to bulk ZnO has a factor of four enhancement in X-ray luminescence, photoluminescence and afterglow intensities in comparison with the sample made with 100% bulk ZnO. [Copyright &y& Elsevier]

Abstract: Highly ordered titanium oxide (TiO2) nanotubes were prepared by electrolytic anodization of titanium electrodes. Morphological evolution and phase transformations of TiO2 nanotubes on a Ti substrate and that of freestanding TiO2 membranes during the calcinations process were studied by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction microscopy. The detailed results and mechanisms on the morphology and crystalline structure were presented. Our results show that a compact layer exists between the tubular layer and Ti substrate at 600°C, and the length of the nanotubes shortens dramatically at 750°C. The freestanding membranes have many particles on their tubes during calcinations from 450 to 900°C. The TiO2 nanotubes on the Ti substrate transform to rutile crystals at 600°C, while the freestanding TiO2 membranes retain an anatase crystal with increasing temperature to 800°C. The photocatalytic activity of TiO2 nanotubes on a Ti substrate annealed at different temperatures was investigated by the degradation of methyl orange in aqueous solution under UV light irradiation. Due to the anatase crystals in the tubular layer and rutile crystals in the compact layer, TiO2 nanotubes annealed at 450°C with pure anatase crystals have a better photocatalytic activity than those annealed at 600°C or 750°C. [Copyright &y& Elsevier]

Fundamental research has been carried out to define optimal “green” synthesis conditions for the production of titania (TiO2) and silver (Ag) nanocomposites (TANCs) ranging from 12.7–22.8 nm in diameter. A bottom-up colloidal approach was employed to accurately control TANC monodispersity and composition. TANCs were found to be effective at inactivating Escherichia coli(E. coli) in water. The presence of Ag in the nanocomposites induced a decrease in TiO2band gap energy, which favoured valence to conduction band electron transfer and allowed for electron excitation using visible light. Aggregation of ultra-fine particles was prevented through the use of a long-chain polymer as evidenced by electrophoretic mobility studies. The TANCs catalyzed oxidation of bacterial membranes and cell death or disinfection. Theoretically, the TANC mode of E. colidisinfection is viawater photolysis, which results in production of hydroxyl radicals and hydrogen peroxide. These interact with the outer membrane polysaccharides and lipids, leading to lipid peroxidation, membrane weakening and resulted in cell death. Our overarching goals were to optimize the variables involved in TANC “green” synthesis and to characterize its nanostructure. High resolution (HR) transmission and scanning electron microscopic (TEM and SEM) studies demonstrated that TANCs were highly crystalline and mono-dispersive. Elemental composition of Ag and Ti, as measured by X-ray energy dispersive (EDS) and X-ray photoelectron spectroscopy (XPS) confirmed sample purity. Ultraviolet-visible (UV-VIS) spectroscopy showed that the energy band-gap of Ag modified TiO2was in the visible range. [ABSTRACT FROM AUTHOR]

Abstract: A new method based on hydrogen pump is presented to measure the electro-osmotic drag coefficient and proton conductivity in Nafion® 117 membrane under similar condition to operating PEMFC. For membranes in contact with liquid water on both sides, electro-osmotic drag coefficient and proton conductivity increase with increasing temperature over the range of 20–90°C while keeping water content inside the membrane constant (λ =22.5) and decrease with decreasing water content in the membrane while keeping temperature of system constant (T =25°C). On the basis of cluster-network model and transport mechanisms of proton and water in ionomeric membrane, the results are discussed. [Copyright &y& Elsevier]

Herein we report an innovative approach using ionic liquid (1-butyl-3-methyl-imidazolium chloride) mediated auto-templating assembly of CaCO3and chitosan to produce well-defined hollow inorganic–organic nanoboxes and nanoframes. By varying experimental conditions, size and shell-thicknesses of hollow nanostructures can be adjusted from 200 to 400 nm and 15 to 75 nm, respectively. [ABSTRACT FROM AUTHOR]

Myostatin (mstn), also known as GDF8, is a growth and differentiation factor of the transforming growth factor-β (TGF-β) superfamily and plays a key inhibitory effect in the regulation of skeletal muscle development and growth in vertebrates. In the present study, to comprehend the role of the mstn2 gene of the yellowfin seabream Acanthopagrus latus (Almstn2b), the genomic sequence of Almstn2b is 2359 bp, which encodes 360 amino acids and is composed of three exons and two introns, was obtained. Two typical regions, a TGF-β propeptide and TGF-β domain, constitute Almstn2b. The topology indicated that Almstn2 was grouped together with other Perciformes, such as the gilthead seabream Sparus aurata. Moreover, Almstn2b was mainly expressed in the brain, fins, and spleen. Furthermore, five SNPs, one in the exons and four in the introns, were identified in the Almstn2b gene. The allele and genotype frequencies of SNP-Almstn2b +1885 A/G were significantly related to the total weight, interorbital distance, stem length, tail length, caudal length, caudal height, body length, and total length (p < 0.05). The allele and genotype frequencies of SNP-Almstn2b +1888 A/G were significantly related to the weight, interorbital distance, long head behind the eyes, body height, tail length, caudal length, and body length. Additionally, the relationship between the SNP-Almstn2b +1915 A/G locus and weight and long head behind the eyes was significant (p < 0.05). Furthermore, the other two SNPs were not significantly associated with any traits. Thus, the SNPs identified in this study could be utilized as candidate SNPs for breeding and marker-assisted selection in A. latus. [ABSTRACT FROM AUTHOR]

Co nanowires have been electroplated into porous Al2O3 templates. The crystalline structure and magnetic properties of Co nanowires of diameters 65 and 200 nm have been studied. Long single crystal Co segments with a hexagonal closed-packed (hcp) structure have been found in the 65 nm-thick nanowires. A mixture of face-centered cubic and hcp single crystal Co segments was observed in the 200 nm-thick nanowires. This finding suggests that the small template pore size favors the growth of hcp Co phase. Magnetic force microscopy measurements showed longitudinal spontaneous magnetic moments in the 65 nm-thick nanowires and transverse moments in the 200 nm-thick nanowires. [ABSTRACT FROM AUTHOR]

With a theoretically high capacity and suitable discharge/charge plateaus, lithium vanadates (such as Li 0.04 V 2 O 5 ) can be used as cathode material for lithium ion batteries. Herein, Li 0.04 V 2 O 5 nanowires are densely anchored onto reduced graphene oxide (rGO) nanosheets to form a Li 0.04 V 2 O 5 @rGO nanocomposite by a hydrothermal method with subsequent thermal treatment. Due to this unique structure, the Li 0.04 V 2 O 5 @rGO exhibits remarkable rate performance and excellent cycling stability. Specifically, it delivers a reversible discharge capacity of 738.09 mA h g −1 at a current density of 100 mA g −1 in the voltage range of 2.0–4.0 V. After 500 cycles, it still maintains a high capacity of 731.70 mA h g −1 , which represents 95.01% retention of the original reversible capacity. These results indicate that the Li 0.04 V 2 O 5 @rGO could be a promising candidate as cathode active material for long-term cycling performance in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

A facile and scalable strategy, based on a hydrothermal route, has been applied to fabricate potassium vanadate (KVO) nanowires on Ti fabric. The morphology, crystal structure, chemical composition of the prepared sample are tested and presented in detail. When tested as cathode materials for lithium-ion batteries, the flexible KVO electrode has a high reversible capacity of 270 mAh g −1 at a current density of 100 mA g −1 after 300 cycles. Furthermore, the KVO delivers outstanding rate behavior, even at 960 mA g −1 , a reversible capacity as high as 214.1 mAh g −1 can be retained. The superior electrochemical performance suggests that the KVO nanowires on Ti fabric can be as a potential cathode candidate for flexible rechargeable lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Compared to halides Cs2HfX6 (X = Cl, Br, I) with a vacancy‐ordered cubic double perovskite structure, the halide Cs2HfF6 (CHF), with a hexagonal Bravais lattice, possesses a higher mass density and chemical stability for radiation detection. Luminescence properties and energy transfer mechanisms of rare‐earths‐doped CHF materials are studied here. The structure of CHF is identified as a new type of vacancy‐ordered hexagonal perovskite, with the same type of building blocks of the double perovskite but stacked with single layers. Density‐functional theory calculations reveal a large bandgap of CHF. A broad emission is observed from the pristine CHF host, which is suggested to be associated with self‐trapped excitons (STEs). A series of rare‐earths‐doped materials are designed utilizing the STE emissions, and efficient energy transfers from STEs and Tb3+ to Eu3+ are achieved for tunable emissions. The codoped material shows stable emission under X‐ray irradiation, with 10.2% reduction from its initial emission intensity, associated with possible structural evolution by radiation‐induced deformation of the soft host. The radiation responses of singly and codoped materials are evaluated, and the codoped material is found to be more sensitive to the radiation energy than the singly doped or pristine CHF for radiation detection. [ABSTRACT FROM AUTHOR]

In this study, CeO 2 nanofibers and that doped with Eu 3+ were prepared via a facile electrospinning route and annealed at different temperatures ranging from 500 to 900 °C. Their structures were investigated using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Photoluminescence properties of the nanofibers were studied in detail. It was found that the nanofibers with Eu% concentration of 0.67 mol.% and annealed at 700 °C exhibited the highest intensities of the luminescence peaks between 550 and 650 nm. [ABSTRACT FROM AUTHOR]

Abstract: Real-time digital imaging of radiation is realized using scintillators, and vertically aligned scintillator structures improve the spatial resolution and detection efficiency. In this work, a cost-effective approach was developed to prepare scintillator CsI nanowires in anodic aluminum oxide (AAO) nanochannels by a mechanical injection method. The AAO walls were pre-deposited with CsI nanoparticles using CsI aqueous solution to facilitate complete filling of the nanochannels. It was observed that although CsI solidifies as dendritic structures in free space on the surface of glass slides, when it is injected into the AAO nanochannels, it solidifies as stable single wires. This mechanical injection method enables fabrication of CsI nanowires with controllable size and chemical doping levels. [Copyright &y& Elsevier]

The critical cooling rate of martensitic transformation cooling from 1300 °C is decreased by one order of magnitude, compared to that cooling from 1000 °C in a Fe-10Cr alloy. Analysis indicates that precursor δ→γ phase transition during cooling from 1300 °C significantly decreases the non-chemical driving force of martensitic transformation. The reduction of non-chemical driving force results from the coarsened size of prior austenite grains as well as the decreased frictional energy of interface motion and defect stored energy. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the operation characteristic of a dead-ended proton exchange membrane fuel cell (PEMFC) placed with vertical orientation is investigated. The relationship between the channel geometry and the wettability of the gas diffusion layer (GDL) surface is theoretically analyzed. Based on the theoretical analysis, straight flow channels with 2.0mm width and 1.0mm depth are used for the experimental investigation and the moisture is condensed at the stack end to improve water removal. The results show that the designed fuel cell can operate for about 1h at 800mAcm−2 and the performance of the cell decreases with the increase in the operation temperature. Moreover, the recovered liquid water is corresponded closely to the theoretical values. [Copyright &y& Elsevier]

Abstract: Graphene nanosheets were effectively functionalized by in situ deposition of hydroxyapatite through a facile chemical precipitation method. Prior to grafting of hydroxyapatite, chemically modified graphene nanosheets were obtained by the reduction of graphene oxide in presence of ethylenediamine. The resulting hydroxyapatite functionalized graphene nanosheets were characterized by attenuated total reflection IR spectroscopy, X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, X-ray energy dispersive spectroscopy, Raman spectroscopy and thermogravimetric analysis. These characterization techniques revealed the successful grafting of hydroxyapatite over well exfoliated graphene nanosheets without destroying their structure. [Copyright &y& Elsevier]

Abstract: Novel mesoporous carbon has been synthesized using rod-like nano-hydroxyapatite (HA) particles as templates, sucrose as carbon precursor by polymerizing, carbonizing and the removal of templates with HCl solution. In the process, HA not only acted as an endotemplate but also an exotemplate producing micropores and mesopores. Subsequently, mesoporous carbon was modified by HNO3 solution with different concentration. The morphology, pore structure, and surface functional groups of the as-obtained samples are analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller method (BET), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The electrochemical performance for electrochemical capacitors is evaluated in a 1M H2SO4 aqueous solution. The results manifest that the structrue of resultant carbon with a high surface area (719.7m2 g−1) and large pore volume (1.51cm3 g−1) is the replica of HA. After modification, the surface area and pore volume mesoporous carbons slightly decrease, while their electrochemical performance have been significantly improved with the increase of the capacitance from 125.7 to 170.1Fg−1 and a non-decayed cycle life over 5000 cycles for HA-C-0.15N. [Copyright &y& Elsevier]

Abstract: Composite membranes containing ePTFE matrix and short side chain perfluoronated sulfonated ionomers are introduced as electrolytes for proton exchange membrane fuel cell applications. The output voltage at 800mAcm−2 for single cell using composite membrane as electrolyte reaches 0.61V at 95°C under 40% relative humidity whereas it is only 0.41V for cell assembled from pristine short side chain perfluoronated sulfonated membrane at the same condition. The performance of fuel cell stack using composite membrane as electrolyte in kilowatts ranges has been experimentally investigated at 95°C under ambient pressure. With the increase in the inlet gas temperature, the performance of the stack is enhanced. The non-monotonic behavior in instantaneous average voltage of single cells in the stack has been observed and the peak value is appeared at the stack temperature of 90°C. The observed water accumulation phenomena suggest that the decrease in stack performance above 90°C is attributed to the lack of water in the system. The results observed in this study demonstrate that the composite membrane has the potential operating at 95°C under reduced relative humidity to 40%, which is a suitable operating condition for fuel cell vehicle applications. [Copyright &y& Elsevier]

Abstract: We have studied the radiation effects in Fe–Zr diffusion couples, formed by thermal annealing of a mechanically bonded binary system at 850°C for 15days. After irradiation with 3.5MeV Fe ions at 600°C, a cross sectional specimen was prepared by using a focused-ion-beam-based lift out technique and was characterized using scanning/transmission electron microscopy, selected-area diffraction and X-ray energy dispersive spectroscopy analyses. Comparison studies were performed in localized regions within and beyond the ion projected range and the following observations were obtained: (1) the interaction layer consists of FeZr3, FeZr2, Fe2Zr, and Fe23Zr6; (2) large Fe23Zr6 particles with smaller core particles of Zr-rich Fe2Zr are found within the α-Fe matrix; (3) Zr diffusion is significantly enhanced in the ion bombarded region, leading to the formation of an Fe–Zr compound; (4) grains located within the interaction layer are much smaller in the ion bombarded region and are associated with new crystal growth and nanocrystal formation; and (5) large α-Fe particles form on the surface of the Fe side, but the particles are limited to the region close to the interaction layer. These studies reveal the complexity of the interaction phase formation in an Fe–Zr binary system and the accelerated microstructural changes under irradiation. [Copyright &y& Elsevier]

Abstract: Herein we report the design of antimicrobial nanohybrids, f-MWCNTs-CdS and f-MWCNTs-Ag2S developed by covalent grafting of cationic hyperbranched dendritic polyamidoamine (PAMAM) onto multiwalled carbon nanotubes (MWCNTs) and successive deposition of CdS and Ag2S quantum dots (QDs). The CdS and Ag2S QDs were in situ deposited on PAMAM grafted MWCNTs instead of anchoring the pre-synthesized QDs. The fourth generation, amine terminated hyperbranched PAMAM was grafted on MWCNTs, which was achieved through repetitive reactions of Michael addition of methylmethacrylate to the surface amino groups and amidation of terminal ester groups with ethylenediamine. The covalent grafting of PAMAM onto MWCNTs and the consecutive conjugation of CdS and Ag2S QDs were characterized using Fourier transform infrared spectroscopy, elemental analysis, powder X-ray diffraction, Raman spectroscopy, transmission electron microscopy and energy dispersive spectroscopy. The antibacterial activity of f-MWCNTs-CdS and f-MWCNTs-Ag2S nanohybrids was evaluated against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus and the results were compared with the activity of carboxylated MWCNTs, PAMAM grafted MWCNTs, PAMAM dendrimer, and CdS and Ag2S QDs. It was found that the germicidal action of MWCNTs was enhanced by grafting of PAMAM, which was further improved with immobilization of CdS and Ag2S QDs. [Copyright &y& Elsevier]

Abstract: Highly ordered freestanding tubular zirconia (ZrO2) membrane was prepared via an electrochemical anodization of zirconium (Zr) substrate in non-aqueous electrolytes (mixture of formamide and glycerol (weight ratio=1:1) containing 1wt% NH4F and 3wt% H2O). Two methods were used to fabricate the two-end opened ZrO2 membranes, one is a potential shock method and another is a reducing potential method. The two-end opened ZrO2 membrane was produced through the detachment of the existing self-organized ZrO2 tubular layer from Zr substrate or sub tubular layer. The microstructures and morphologies of the samples were studied by scanning electron microscopy and the growth mechanisms of the two-end opened ZrO2 nanotube arrays were investigated. [Copyright &y& Elsevier]

Zirconia (ZrO) nanotubes have been synthesized using a facile anodizing process in organic electrolyte systems containing a low content of fluoride. The nanotube architecture evolution was recorded at different anodization periods (1-24 h) by scanning electron microscopy. A compact layer was found between the Zr substrate and its upper tubular layer after 1 h of anodization, whereas after further anodization for 3 h the compact layer disappeared. Meanwhile, ZrO nanotubes turned to a uniform structure from top to bottom. However, after 18-24-h-long anodization, the uniform tubular layer was replaced by a random layer composed of various structural defects. Since the compact layer was not completely dissolved, the retained compact layer yielded O-rings with double walls on the outer surface of the nanotubes. [ABSTRACT FROM AUTHOR]

Abstract: Herein a simple and effective approach is introduced to functionalize single walled carbon nanotubes (SWCNTs) by in-situ grafting of hydroxyapatite (HA). The pristine SWCNTs were chemically activated through introduction of carboxylic groups on their surfaces by refluxing in the mixture of H2SO4 and HNO3. The resulting carboxylated SWCNTs were further utilized for grafting of HA. The Fourier transform infrared and Raman spectroscopic studies demonstrated the formation of HA and its grafting over SWCNTs. The phase composition of HA and existence Ca2+ and PO4 3− ions were studied using X-ray diffraction and energy dispersive X-ray analyses, respectively. The surface morphology of functionalized SWCNTs was analyzed using scanning electron microscopy and transmission electron microscopy. Thermogravimetric analysis confirmed the existence of HA on SWCNTs by exhibiting different thermogram for pure HA and functionalized SWCNTs. Overall, this method produced uniform grafting of low crystalline HA on carboxylated SWCNTs with strong interfacial bonding. [Copyright &y& Elsevier]

Abstract: Engineered nanomaterials display significant advantages due to their unique nanostructure, along with their tuneable properties for the designed application. Silver nanoparticles (Ag-NPs) have drawn attention due to their use as potent bactericidal agents and were characterized in this research to provide an understanding of the interaction between nanomaterials and bacteria. This work presents the bactericidal performance of Ag-NPs using Escherichia coli (E. coli) as a model microorganism. Several state-of-the-art techniques, such as high-angle annular dark-field detector in scanning transmission electron microscopy, and energy filtered imaging in electron energy loss spectroscopy, were employed to obtain nanostructural and elemental information. The bactericidal activities of Ag-NPs were then compared with two commonly used disinfectants, sodium hypochlorite (NaClO) and phenol (C6H5OH). These two chemical disinfectants exhibited rapid bactericidal activity, showing a minimal bactericidal concentration (MBC) of 16 parts-per-million (ppm) and 16 part-per-thousand (ppth), respectively for NaClO and C6H5OH within about 10min. In contrast, Ag-NPs exhibit slow but long-term bactericidal effect demonstrating MBCs of 0.6 parts-per-million (ppm) within 6h when used as disinfectant. An advantage using Ag-NPs to inactivate E coli at low dosages is negligible environmental waste or hazardous by-products. The results showed that Ag-NPs caused bacterial inactivation by a mechanism involving several steps, including cell wall and cytoplasmic membrane damage. [Copyright &y& Elsevier]

Abstract: Silver nanoparticles (Ag-NPs) were synthesized using a facile green chemistry synthetic route. The reaction occurred at ambient temperature with four reducing agents introduced to obtain nanoscale Ag-NPs. The variables of the green synthetic route, such as acidity, concentration of starting materials, and molar ratio of reactants were optimized. Dispersing agents were employed to prevent Ag-NPs from aggregating. Advanced instrumentation techniques, such as X-ray powder diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible spectroscopy (UV–vis), and phase analysis light scattering technique (ZetaPALS) were applied to characterize the morphology, particle size distribution, elemental composition, and electrokinetic behavior of the Ag-NPs. UV–vis spectra detected the characteristic plasmon at approximately 395–410nm; and XRD results were indicative of face-centered cubic phase structure of Ag. These particles were found to be monodispersed and highly crystalline, displaying near-spherical appearance, with average particle size of 10.2nm using citrate or 13.7nm using ascorbic acid as reductants from particle size analysis by ZetaPALS, respectively. The rapid electrokinetic behavior of the Ag was evaluated using zetapotential (from −40 to −42mV), which was highly dependant on nanoparticle acidity and particle size. The current research opens a new avenue for the green fabrication of nanomaterials (including variables optimization and aggregation prevention), and functionalization in the field of nanocatalysis, disinfection, and electronics. [Copyright &y& Elsevier]

Abstract: We fabricate single-crystal Pb, Sn, and Zn nanowires, of length 6 or 60μm and diameter 30–250nm, using an in situ template-based electrochemical method. In this approach, a single nanowire is formed in contact with a pair of bulk film electrodes of Au, Sn, or Pb. We observe that, with superconducting electrodes having a higher critical temperature T c , superconductivity is induced in Sn and Zn nanowires at the T c of the electrodes for nanowires as long as 60μm. With Au electrodes, superconductivity is suppressed completely in 6μm-long nanowires and partially in 60μm-long nanowires. Based on transmission electron microscopy studies, the nanowires are single crystalline. Analysis of the temperature dependence of the normalized resistance suggests that the residual-resistance-ratio plays an important role in the observed anomalous long-range proximity effect. [Copyright &y& Elsevier]

As an ideal reinforcing phase, nano-carbon has been widely used to improve the properties of composites. In this paper, Mo–Cu–Zr ternary composites were reinforced with various types and contents of nano-carbon to find the optimal composition and the microstructure and mechanical properties of the composites were systematically characterized and analyzed. The composites were fabricated via a powder metallurgy method to achieve high compactness and structural uniformity. The analysis results show that the increase of nano-carbon may cause a serious agglomeration and subsequent decrease of the composite compactness, while the synergetic effect of carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) can improve their dispersion. The 0.8C + 0.2G-MCZ3 composite showed the best comprehensive properties, which achieved a relative density, hardness and compressive strength of 99.7%, 343.6 HV and 953.5 MPa, respectively. Moreover, the component Zr mainly formed solid solution and compound particles with Cu or C through in-situ chemical reactions. It played an important role in solid solution strengthening and dispersion strengthening, and the in-situ synthesized ZrC nanoparticles on nano-carbon surfaces can pin interfaces and improve the effect of load transfer. The synergetic effects and multiple strengthening mechanisms result in the improvement of the microstructure and properties of the composites. [Display omitted] • Interfaces between nano-carbons and matrix are improved by the in-situ synthesized phase. • The synergy of CNTs and GNPs shows a better reinforcing effect. • The increase of Zr content is beneficial to the improvement of the properties of composites. • Multiple strengthening mechanisms synergistically act on the improvement of composite properties. [ABSTRACT FROM AUTHOR]

Thermoresponsive dielectric materials have attracted the interest of researchers as they exhibit very important application prospects in stimuli-responsive smart devices. In this contribution polyethylene glycol (PEG), impregnated in halloysite nanotubes (HNTs), was incorporated into poly(vinylidene fluoride) (PVDF) for tailoring the thermoresponsive dielectric properties based on a non-ferroelectric phase transition. The PVDF/PEG/HNTs displayed a remarkable rise of dielectric constant between 20 and 30 °C. The mechanism is related to the enhanced orientational polarization effect triggered by the solid–liquid phase transition of the PEG. This make it possible to design stimuli-responsive smart materials through a simple, low-cost and efficient strategy. The present work provides an alternative and innovative routine for tailoring thermal-induced dielectric behaviors via a non-ferroelectric phase transition by introducing PEG into a high-dielectric-constant polymer matrix. [ABSTRACT FROM AUTHOR]

Streptococcus iniae has become one the most serious aquatic pathogens causing invasive diseases in farmed marine and freshwater fish worldwide, and orally attenuated vaccine is still the best option in protecting these invasive diseases. In this study, the safety, stability, immunogenicity of the S. iniae attenuated strain YM011 were evaluated, and comprehensively analyzed its virulence weakening mechanism at whole genome level. The results shown that attenuated S. iniae strain YM011 completely lost its pathogenicity to tilapia and had good immunogenicity with relative percent survival being 93.25% at 15 days and 90.31% at 30 days via IP injection, respectively, and 76.81% at 15 days and 56.69% at 30 days via oral gavage, respectively. Back-passage safety assay indicated that YM011 did not cause diseases or death in tilapia after 100 generations of serial passaging. Comparative genome-wide sequencing shown that YM011 had a 0.4 M large inversion fragment compared with its parental strain virulent strain GX005, which encoded 372 genes including drug resistance genes pbp2A and tet, as well as known virulence factors including hemolysin transport system gene, recA, and mutator family transposase. The attenuated S. iniae strain YM011 is an ideal attenuated oral vaccine candidate with good immunogenicity, safety and stability. Abnormal expression of important drug resistance genes as well as known virulence factors due to inversion of a 0.4 M large fragment is the leading mechanism underlying its attenuated virulence. • Developed an S.iniae attenuated strain via continuous in vitro passaging. • Genome-wide analysis between S.iniae attenuated strain and its parental virulent strain. • A 0.4 M large fragment is the leading mechanism underlying the attenuated virulence. [ABSTRACT FROM AUTHOR]

In this work, α-Al 2 O 3 whisker reinforced Cu-graphite matrix composites were prepared by spark plasma sintering. Results show that the surface modification of α-Al 2 O 3 whiskers with sodium dodecyl sulfate solution can improve its dispersibility, and the composites obtained are basically completely dense. The relative density of all composite materials is above 95%. The interface bonding mode in the composite is mainly mechanical bonding, and the formation of a diffusion layer is also observed from interfaces. With the increase of α-Al 2 O 3 whisker content, mechanical properties of the composites increase first and then decrease. The composite with 1.0 wt% α-Al 2 O 3 whisker has the best performance. The corresponding relative density, hardness and compressive strength are 96.35%, 56.20 HV, 139.12 MPa, respectively. By analyzing microstructure and fracture morphology of the composites, it is determined that the strengthening mechanisms are mainly fine grain strengthening, particle strengthening and load transfer. Simultaneously, the fracture type is brittle fracture. Unlabelled Image • The α-Al 2 O 3 whisker reinforced Cu-graphite composites were prepared via SPS. • The interface between the matrix and α-Al 2 O 3 whisker was analyzed. • The strengthening mechanism of Cu-graphite composites was investigated. • Fracture mechanisms of the composites were analyzed systematically. [ABSTRACT FROM AUTHOR]

An online monitoring technology of Pu-239 aerosol based on aerosol direct introduction device, membrane desolvation nebuliser and ICP-MS was established for workplaces of reprocessing plants. Briefly, 0.8 l min−1 Pu-239 aerosol from the workplace was introduced into the aerosol direct introduction device where the air was replaced by Argon, and then the aerosol was introduced into the ICP-MS for measurement. To determine the activity of Pu-239 aerosol, 1.10E−3 Bq ml−1 Pu-242 standard solution generated by a membrane desolvation nebuliser was used. The introduction efficiency of the nebuliser was determined by sampling the aerosol generated from the nebuliser with Lead Standard Solution by glass fiber filter, which was (26.82 ± 3.33) %. The mass bias between Pu-239 and Pu-242 for the ICP-MS measurement was determined by Pu-239 and Pu-242 standard solutions generated by the nebuliser, and mass discrimination correction factor for Pu-239/Pu-242 was 0.972 ± 0.010. The limit of detection (LOD) and limit of quantification (LOQ) of this system were calculated according to the ISO 20 899:2018, which were 2.24E−05 Bq m−3 and 7.45E−05 Bq m−3 with 1 min measurement. The main interference which was from U-238 was determined by U-238 standard solution generated by the nebuliser, and the interferences of U-238 to 239 was (8.50 ± 1.05) E−05. According to the counts of U-238 from several workplaces of reprocessing plant where this system was tested, 239 counts rate from the interferences of U-238 of those workplaces were at the same level of the system background counts, which meant that the LOD above was suitable for those places. [ABSTRACT FROM AUTHOR]

In this study, Al 2 O 3 –TiC composites synergistically reinforced with multi-walled carbon nanotubes (MWCNTs) and graphene nanoplates (GNPs) were prepared via spark plasma sintering (SPS). The effects of the MWCNT and GNP contents on the phase composition, mechanical properties, fracture mode, and toughening mechanism of the composites were systematically investigated. The experimental results indicated that the composite grains became more refined with the addition of MWCNTs and GNPs. The nanocomposites presented high compactness and excellent mechanical properties. The composite with 0.8 wt% MWCNTs and 0.2 wt% GNPs presented the best properties of all analysed specimens, and its relative density, hardness, and fracture toughness were 97.3%, 18.38 ± 0.6 GPa, and 9.40 ± 1.6 MPa m1/2, respectively. The crack deflection, bridging, branching, and drawing effects of MWCNTs and GNPs were the main toughening mechanisms of Al 2 O 3 –TiC composites synergistically reinforced with MWCNTs and GNPs. [ABSTRACT FROM AUTHOR]

A novel function of maleic anhydride grafted polypropylene (PP) with different backbone chain-lengths was demonstrated, i.e., in controlling the cobalt morphologies (dispersed polyhedral vs. assembled chain nanostructure), crystalline structures (ε- vs.β-phase), and magnetic property (242 vs. 808 Oe) in the synthesized magnetic PP nanocomposites. [ABSTRACT FROM AUTHOR]

Simple Summary: Patients who were infected with Streptococcus agalactiae (ST1) were mainly associated with asymptomatic carriage. However, the invasive diseases in non-pregnant adults caused by S. agalactiae (serotype V, ST1) have increased recently. We have previously reported that human-derived S. agalactiae (serotype V, ST1) could infect tilapia with virulence and pathologic characteristics similar to highly virulent tilapia-derived S. agalactiae (ST7) strains. The potential risk of cross-species infection cannot be ignored. Therefore, our research provided a multi-omics analysis of the human-derived serotype V ST1 S. agalactiae strains, which were virulent and non-virulent to tilapia and provided a more comprehensive understanding of the virulence mechanism. Our previous study showed that human-derived Streptococcus agalactiae (serotype V) could infect tilapia, but the mechanism underlying the cross-species infection remains unrecognized. In this study, a multi-omics analysis was performed on human-derived S. agalactiae strain NNA048 (virulent to tilapia, serotype V, ST1) and human-derived S. agalactiae strain NNA038 (non-virulent to tilapia, serotype V, ST1). The results showed that 907 genes (504 up/403 down) and 89 proteins (51 up/38 down) were differentially expressed (p < 0.05) between NNA038 and NNA048. Among them, 56 genes (proteins) were altered with similar trends at both mRNA and protein levels. Functional annotation of them showed that the main differences were enriched in the arginine deiminase system signaling pathway and biotin metabolism signaling pathway: gdhA, glnA, ASL, ADI, OTC, arcC, FabF, FabG, FabZ, BioB and BirA genes may have been important factors leading to the pathogenicity differences between NNA038 and NNA048. We aimed to provide a comprehensive analysis of the human-derived serotype V ST1 S. agalactiae strains, which were virulent and non-virulent to tilapia, and provide a more comprehensive understanding of the virulence mechanism. [ABSTRACT FROM AUTHOR]

Text classification is an important task in machine learning. Specifically, deep neural network has been shown strong capability to improve performance in different fields, for example speech recognition, objects recognition and natural language processing. However, in most previous work, the extracted feature models do not achieve the relative text tasks well. To address this issue, we introduce a novel multi-task learning approach called a hybrid representation-learning network for text classification tasks. Our method consists of two network components: a bidirectional gated recurrent unit with attention network module and a convolutional neural network module. In particular, the attention module allows for the task learning private feature representation in local dependence from training texts and that the convolutional neural network module can learn the global representation on sharing. Experiments on 16 subsets of Amazon review data show that our method outperforms several baselines and also proves the effectiveness of joint learning multi-relative tasks. [ABSTRACT FROM AUTHOR]

• A Co interlayer has been proposed to bond TC4 titanium alloy and 4J29 kovar alloy. • The use of Co interlayer can inhibit the formation of Fe-Ti intermetallic compounds. • The bonding mechanism of TC4/Co/4J29 bonded joints is investigated. • By decreasing the bonding temperature, the quality of TC4/Co/4J29 bonded joints can be improved. The diffusion bonding of TC4 titanium alloy and 4J29 kovar alloy was conducted using pure Co interlayer. The results showed that maximum tensile strength of 58.5 MPa was acquired for bonded joint made at 825 °C. At titanium alloy side, due to formation Ti-Co phases, such as TiCo 3 , TiCo 2 , TiCo and CoTi 2 , brittleness of bonded joints was enhanced. Furthermore, with increase in bonding temperature, tensile strength of bonded joints gradually decreased because of the production of Ti-Co intermetallic compounds with a thicker thickness. [ABSTRACT FROM AUTHOR]

Al-Si alloy nanocomposites reinforced with nano-carbon (carbon nanotubes (CNTs), graphene nanoplatelets (GNPs)) and in-situ Al 2 O 3 were fabricated via the process of surface modification, ball milling and hot isostatic pressing (HIP). The microstructure and mechanical properties of the nanocomposites were tested and analyzed. The interface between nano-carbon and Al matrix bonded tightly for reacting at the interface to form Al 4 C 3 , and the in-situ synthesis Al 2 O 3 particles were dispersively distributed and had high bond strength with Al matrix. The nanocomposites show high compactness (≥98.5%) and excellent mechanical properties, the hardness, tensile, compressive and shear strength of the nanocomposite with 1.0 wt% CNTs are 96.4 HV, 237.7 MPa, 389.5 MPa and 130.3 MPa, respectively. The interface bonding mechanisms and strengthening mechanisms were studied in detail. The results show that the reinforcement phases mainly reinforce the nanocomposites by grain refinement strengthening, dislocations strengthening, particles strengthening and load transfer. • The Al-Si nanocomposites with isotropic microstructure and excellent mechanical properties were prepared via HIP. • The synergetic effect of nano-carbon and in-situ Al 2 O 3 in the nanocomposites were investigated. • The structure and interface of the nanocomposites were analyzed and discussed in detail. • Strengthening and fracture mechanisms of the nanocomposites were analyzed systematically. [ABSTRACT FROM AUTHOR]

Contact pressure is a crucial factor which can affect fretting fatigue (FF) life significantly. In this research, the influence of contact pressure on torsional fretting fatigue (TFF) damage of a 7075 aluminum alloy is investigated. According to the experiment results, below 72.5 N⋅m torque as the contact pressure increases, the TFF life decreases firstly and then it reaches to the lowest point at 300 N, while afterward the TFF life increases. The P - N curve shows a C shape. The damage analysis results show that with increasing the contact pressure, the damage becomes severer. The oxidative products are mainly Al 2 O 3 and Al(OH) 3 , and the loading side is found to be more oxidized than the center position and fixed side. • The P - N curves show a C shape. • The ratio Q/P is inversely correlated with the contact pressure. • The degree of oxidation increases with the contact pressure, and the main oxidative products are Al 2 O 3 and Al(OH) 3. • There are three stages of the crack propagation, and the crack directions are around 30°, 60° and 45° to the contact surface. [ABSTRACT FROM AUTHOR]

• Metallic Co nanoparticles are in-situ deposited into the discharged TiO 2 nanotube array. • After calcination, the resulting TiO 2 @Co composite has excellent ferromagnetic properties. • The maximum saturation magnetization of TiO 2 @Co composite is 15.85 emu/g. Titanium oxide (TiO 2) nanotube array is prepared by an anodization method, and the TiO 2 nanotube array and a lithium foil are used as working and counter electrodes, respectively, to assemble a lithium-ion battery. After discharge to 0.01 V, the TiO 2 nanotube array is reducible. Metallic Co nanoparticles are in-situ deposited into the discharged TiO 2 nanotube array in saturated cobalt acetate in N-N dimethylformamide solution for the first time. The sample exhibits enhanced magnetic properties after calcination at 500 °C in a reducing agent. The morphology, structure and magnetic properties of the samples are characterized and analyzed in detail. This work provides a new method for the synthesis of one-dimensional functional materials by using TiO 2 nanotube array template. [ABSTRACT FROM AUTHOR]

Coherent acoustic and optical phonon oscillations in Bi nanowire samples were studied with a femtosecond pump-probe technique. Laser pulses of 50 fs excited simultaneously acoustic oscillations at a frequency of about 9.5 GHz and optical phonons in the terahertz range. The transmission signal of nanowires on a glass substrate and the signal of light scattered from freestanding nanowires were measured. The acoustic velocity in nanowires was found to be close to that of bulk polycrystalline material. The changes in the optical phonon frequency at different laser fluences were simulated taking into account excitation inhomogeneity, lattice anharmonicity, diffusion, and recombination of the carriers and gave good agreement with experimental results. [ABSTRACT FROM AUTHOR]

WC-2wt.%ZrO 2 -1wt.%Ni composites were prepared by vacuum pressureless sintering (VPS) and post-hot isostatic pressing (post-HIP). The microstructure, phase composition, densification, hardness, fracture toughness, and flexural strength of composites with different Ni and ZrO 2 contents were systematically investigated. The results show that WC-Ni and WC-ZrO 2 -Ni composites prepared by VPS can be densified by the addition of a small amount of Ni as the binder phase. Moreover, the densities of the composites can be further enhanced i.e. the composites are rendered nearly fully dense following HIP while the grains remain fine without obvious growth. The binder Ni and ZrO 2 phases are uniformly distributed in the WC matrix and exhibit high bonding strength with it. The hardness, fracture toughness, and flexural strength of the WC-ZrO 2 -Ni composites following HIP could reach 22.4 GPa, 12.0 MPa m1/2, and 1101.2 MPa, respectively. Based on the influence of the Ni and ZrO 2 contents on the microstructures and mechanical properties of the WC-2wt.%ZrO 2 -1wt.%Ni composites, the fracture mechanism was determined to be governed by the phase transformation of ZrO 2 that led to the development of some micro-cracks followed by deflection, bridging, and branching of the cracks to improve fracture toughness. The composites are mainly composed of elongated triangular prismatic WC grains and ZrO 2 phases, and hence the fracture mode can change such that transgranular fracture becomes the main fracture mode accompanied by a small amount of intergranular fracture. Thus, the flexural strength of the composites can be improved. [ABSTRACT FROM AUTHOR]