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So far, developed microwave absorbers exhibit significant changes in absorption with temperature, which hinder their operation within a wide temperature range. In this paper, a microwave absorber based on SiBCN ceramics was prepared. Due to the excellent high‐temperature stability of SiBCN ceramics, its permittivity changes less with temperature, avoiding the issue of performance deterioration or even failure that traditional refractory absorbers face at high temperatures. The experiment proves the absorption bandwidth for –15 dB of the SiBCN metamaterials absorber (SMA) is 12 GHz at 800°C, with a maximum absorptivity of 99.99%. According to the computed data, the resonance loss contributes 81.9 to 94.5% of the microwave absorption of SMA. This work demonstrates significant potential for applications in radar stealth under harsh conditions. [ABSTRACT FROM AUTHOR]

Electron backscatter diffraction (EBSD) can be employed to determine crystal structures but has not been used alone to identify defects at the atom scale due to the lack of understanding of the EBSD patterns generated by various structure defects. In the present work, the EBSD patterns of FCC‐Fe with 9‐layer, 6‐layer and 3‐layer twin structures are simulated, respectively, using the revised real space (RRS) method and compared with the counterpart of perfect crystals. Our results show that when the electron beam is incident along a direction parallel to the twin plane, the pattern appears symmetrical with respect to the corresponding Kikuchi band of the twin plane, and the diffraction details within the Kikuchi band also exhibit symmetry with respect to the middle line of the Kikuchi band. Moreover, the overall clarity of the patterns decreases, and the pattern becomes more blurred with increasing the distance from the Kikuchi band corresponding to the twin plane. By contrast, the incident electron beam along the direction perpendicular to the twin plane results in diffraction superposition of the matrix region and the shear region, which shows twofold rotational symmetry with respect to the Kikuchi pole corresponding to the normal to the twin plane. In addition, some extra Kikuchi bands appear in the EBSD patterns due to the long‐period structures of the multilayer twins. As the number of multilayer twins decreases, the number of extra Kikuchi bands decreases and the area of the blurring pattern increases. The correlation between twin structures and EBSD patterns provides theoretical insights for identifying twin structures by the EBSD technique. [ABSTRACT FROM AUTHOR]

Excellent thermostable performance is the basis for the further development of microwave absorbing materials in the field of military stealth. Herein, a high‐temperature metamaterial absorber (HMA) with high impedance patterns (multi‐octagonal‐rings), two quartz (SiO2) layers, and a metallic ground film is designed and simulated. The optimal structural parameters are obtained by optimizing the circuit parameters and the size of HMA. The interaction of electric and magnetic resonance in multioctagonal rings results in a wide absorption bandwidth and excellent absorption performance. The experimental results show that the structure has good impedance matching performance, and the effective absorption bandwidth (−10 dB) (EAB) of the structure can reach 10.6 GHz from room temperature to 700 °C under the combined effect of resonance loss and ohmic loss. [ABSTRACT FROM AUTHOR]

With two groups of numerical experiments with and without the cold-core eddy (CCE), the impacts of the CCE on the upper-ocean responses to Typhoon Trami (2018) were investigated using a coupled atmosphere–ocean model. It is commonly accepted that the CCE promotes the sea surface cooling (SSC) primally through the enhanced vertical mixing, while the contributions from the wind-driven advection and the near-inertial advection to the differences in the sea surface temperature (dSST) were underestimated. This study found that the presence of CCE contributed to the stronger along-track cold advection, which dominated the increase in the SSC near the radius of maximum wind (RMW) to the right of Trami's track, and the stronger cross-track warm advection was acting to prevent the cooling induced by the vertical mixing. During the relaxation stage, the stronger near-inertial advection within the CCE accounted largely for the amplification and the redistribution of the dSST. As for the dynamic responses, the enhanced upwelling and downwelling within the CCE explained the larger cooling and warming in the subsurface temperature oscillations. The wind-driven acceleration of the currents in the mixing layer was larger during the typhoon–eddy interaction so that the CCE became an efficient mixer, thus contributing to the rapid surfacing of the cold water and the ensuing stronger wind-driven advection. These results highlight the importance of the advection processes in the modulating effect of the CCE. Therefore, 3D ocean models are needed to incorporate the mesoscale features of the oceanic eddies for realistically reproducing the upper-ocean responses to tropical cyclones (TCs). [ABSTRACT FROM AUTHOR]

The duration of the eyewall replacement cycle (ERC) in typhoons is determined by the rate of dissipation of the inner eyewall and intensification of the outer eyewall, which is an important indicator for predicting changes in the intensity and structure of typhoons. Previous studies on ERCs have focused on the internal storm dynamics associated with the interactions between the concentric eyewalls (CEs), but the impacts of the sea surface cooling (SSC) on ERCs remain not adequately investigated. The slow movement of Typhoon Trami results in remarkable SSC. Using a coupled atmosphere–ocean model, the simulation for Trami generates an ERC that matches observations, whereas an unrealistic long-lived ERC is produced in the uncoupled simulation. Numerical simulations suggest that the typhoon-induced nonuniform SSC cannot only weaken the typhoon, but can also modulate the duration of the ERCs. The SSC acts like a catalyst for triggering the negative feedback between the surface heat exchange and the circulations of Trami to reduce the energy supply to the inner eyewall more severely where the sea surface temperature (SST) dropped more sharply. The SSC works in concert with the interactions between the CEs to weaken the inner eyewall faster, thus terminating the ERC of Trami rapidly. The results indicate that a better understanding of the modulation effect of SSC is required for the accurate forecast of ERCs. Significance Statement: The duration of the eyewall replacement cycle in typhoons is determined by the rate of dissipation of the inner eyewall and intensification of the outer eyewall. While much is known about the cutoff effects of the outer eyewall on the dissipation of the inner eyewall, few studies have examined the dissipation induced by sea surface cooling. Using the coupled atmosphere–ocean model, the simulation for Trami generates an eyewall replacement cycle that matches observations, whereas an unrealistic long-lived one is produced in the uncoupled simulation. The results suggest that the typhoon-induced nonuniform sea surface cooling cannot only weaken the typhoon, but can also modulate the duration of the eyewall replacement cycle, which is essential for the accurate forecasting of eyewall replacement cycles. [ABSTRACT FROM AUTHOR]

A broadband metamaterial absorber (MA) with high‐temperature resistance is designed and fabricated using a regular octagonal ring‐cross structure as a frequency‐selective surface (FSS). A high‐temperature conductive paste and SiO2 are used as the FSS raw materials and middle layer, respectively. Simulation and experimental results show that the absorber reaches a reflection loss below −5 dB at the 5.17–18 GHz range with normal incidence at room temperature. The measured values are in good agreement with the simulation results. At 800 °C, the absorption bandwidth expands to 13.3 GHz (4.72–18 GHz). The equivalent impedance of the absorber is obtained using an inversion method to qualitatively explain its working mechanism. The electric energy density, magnetic energy density, and surface current at the resonance frequency provide an intuitive understanding of the power loss of the structure. Comprehensive analysis illustrates that the main absorption mechanisms of the high‐temperature broadband MA (HBMA) are ohmic and resonance losses. [ABSTRACT FROM AUTHOR]

The investigation focused on microstructural changes and hot corrosion behavior in various salt environments (Na 2 SO 4 + 25 wt% K 2 SO 4 and Na 2 SO 4 + 25 wt% NaCl) at 900 °C of NiCoCrAlYSi laser cladding coatings before and after high-current pulsed electron beam (HCPEB) irradiation. HCPEB treatment effectively eliminated imperfections like micropores and segregation of the components, creating a remelted layer with high-density dislocations and nanostructure. The irradiated impacts including polishing, purification, composition homogenization, and grain refinement facilitated the development and self-repair of a compact and tenacious oxide scale. This enhanced oxide layer effectively mitigates extensive corrosive media erosion. The utilization of HCPEB treatment has shown significant potential in enhancing the hot corrosion resistance of NiCoCrAlYSi laser claddings. [Display omitted] • HCPEB treatment removed defects, induced dislocations and nanostructures. • Improved oxide layer via HCPEB reduced corrosive erosion. • Polishing, homogenization and grain refinement enabled self-repairing oxide scale. • HCPEB enhanced hot corrosion resistance in MCrAlY laser cladding coatings. [ABSTRACT FROM AUTHOR]

The bandwidth adaptation factor (BAF), which is calculated as BW • (λ L - λ H): (d • f r), is a crucial evaluation parameter for designing ultrathin broadband absorbers. In this paper, a high BAF absorber is designed by utilizing an impedance frequency selective surface (FSS), which includes a six pinnacles FSS, a La-doped mullite ceramic dielectric layer and a metal backplane. The optimal numbers of pinnacled FSS is determined through comparison and optimization, and the power monitor results indicate that the main loss modes are electrical and ohmic loss. Subsequently, the impedance analysis reveals that the favourable absorption performance is attributed to good impedance matching and high loss coefficient. Furthermore, the observation of the current distribution on the surface confirms that the primary loss appears at the pinnacles. The proposed absorber has below −10 dB reflectivity in 12.26–18.00 GHz. Meanwhile, the BAF is 3.36 and the thickness is only 0.061 λ L (1.5 mm). The measured results are in good agreement with the simulation results, demonstrating an excellent BAF characteristic. [ABSTRACT FROM AUTHOR]

The effect of nano-zirconia addition on the microstructure and properties of corundum castables was studied using corundum, kyanite, alumina powder, gel powder, and nano-ZrO 2 as raw materials. The results showed that adding 1.2(wt)% nano-ZrO 2 could reduce the median pore diameter of the castables from 480 to 200 nm at 110 °C. After the castables were heated at 1100 °C, the cold modulus of rupture increased by 29.95%, to 24.71 MPa, and the cold compressive strength increased by 50.32%, to 116.37 MPa. The hot modulus of rupture increased by 114.95%, to 3.59 MPa after being treatment at 1500 °C, the high surface energy of nano-ZrO 2 can increase the interface energy and bonding strength between adjacent particles. [ABSTRACT FROM AUTHOR]

Designing microwave absorbers with broadband perfect absorption at high temperatures remains a challenge for researchers due to the variability of material properties with temperature. Herein, inspired by the absorption model of Papilio blumei, this work establishes a method to realize broadband metamaterial microwave blackbody using polymer ceramics and bionic metamaterial structures. The size of the high-temperature resistive film and biomimetic hole of the bionic metamaterial microwave absorber (MMA) is optimized based on the trust region framework method. The absorption rate of the MMA reached 99% across the C ~ Ku bands, which breaks the Plank-Rozanov limit by multiple absorption mechanisms (polarization loss, conductive loss, and resonance loss). It is evident from quantitative calculations and power loss density distributions that resonant losses are crucial for microwave energy absorption. Experiment results reveal that the MMA can maintain excellent absorption performance from room temperature to 1000 ℃ which guarantees the potential application for microwave absorber at evaluated temperatures. [ABSTRACT FROM AUTHOR]

An arc ion-plated NiCoCrAlYHfSi coating modified by a high-current pulsed electron beam (HCPEB) was examined in this study. The dynamic growth behavior and formation mechanisms of the thermally grown oxide (TGO) of the original and modified coatings were thoroughly compared by isothermal oxidation at 1050 °C. HCPEB irradiation led to the transformation of the rough original coating into a flat, smooth, and dense structure. Furthermore, Y-Al nanoparticles and high density of dislocations were also obtained in the modified layer. These modification characteristics can establish favorable conditions for the rapid accumulation and stable growth of the protective Al 2 O 3 particles. With the extension of oxidation time, the CrO 3 formed in the oxide film left many small pits after volatilization, but these pits were filled with Al 2 O 3 particles. Compared with the oxide film of the original coating, the TGO of the modified coating is flat, continuous, and dense, and its growth rate is notably slower. Also, the growth of Ni, Cr, and Co rich oxides was expectantly restrained. Obviously, the HCEPB technique has the capacity to change the growth behavior of the TGO and significantly enhance the coating's resistance to high-temperature oxidation. • Surface modification of MCrAlY coating treated by high-current pulsed electron beam was studied. • A polished surface and completely remelted layer were formed. • The dynamic growth process and evolution mechanism of oxide film were analyzed. • The modification effects can promote the rapid formation and steady growth of protective oxide film. • The modified coating exhibits a superior high-temperature oxidation resistance. [ABSTRACT FROM AUTHOR]

• Zr incorporated SCM-1 with delaminated structure was prepared by a post-synthesized method. • Zr-Al-SCM-1 zeolites are active in conversion of furfural and xylose to GVL. • As high as 36.4% yield of GVL was achieved from xylose with excellent stability over Zr-Al-SCM-1 (4). A series of delaminated MWW-type Zr-Al-SCM-1 zeolites with large external surface area have been synthesized through a post-synthesized method by partial dealumination of SCM-1 and Zr incorporation based on parent SCM-1 zeolite, and used in the conversion of furfural and xylose to γ-valerolactone (GVL). The characterization of catalysts using XRD, FTIR, 29Si NMR, Raman, UV–vis and XPS spectroscopy confirmed the preservation of the parent SCM-1 zeolite network as well as the incorporation of Zr atoms into the zeolite framework with tetrahedral coordination. NH 3 -TPD and Py-FTIR spectroscopy reveal that the Zr-Al-SCM-1 zeolites possess both Brønsted and Lewis acid sites. When they are applied to the one-pot cascade conversion of furfural, a remarkable GVL yield of 47.3% with 85.6% carbon balance is obtained at 170 °C after 28 h. When considering xylose as starting substrate, up to 36.4% yield of GVL is achieved over Zr-Al-SCM-1 zeolites with excellent recyclability at 170 °C after 48 h. Moreover, the catalyst shows far superior catalytic performance and stability compared to the commercial MCM-22 based zeolites (Zr-Al-MCM-22). [ABSTRACT FROM AUTHOR]

The work was to develop novel high temperature microwave absorbing material based MgZr 4 (PO 4) 6 (MZP) ceramic. The results show that thermal expansion process at higher temperature expand along c-axis while shrink along the a-axis. The conductivity of MZP ceramic was increased by 1000 orders due to the increase in magnesium ion mobility. In addition, the results indicates that the dielectric properties were dependent on temperature at all measured frequencies. The real and imaginary parts of dielectric constant increased from 4.0–5.2 and 0.024 to 0.4, respectively. The reflection loss varied with the change in thickness and the minimum reflection loss value was -26.66 dB at 800℃, suggesting that MZP ceramic was a promising novel high temperature microwave absorbing material. [ABSTRACT FROM AUTHOR]

The effects of in-situ synthesis columnar mullite and pore structure on the hot modulus of rupture (HMOR), thermal shock resistance and corrosion resistance of corundum castables have been investigated in this paper. When 2% nano silica was added, the pore diameters of castables could be decreased to 15 nm (at 110 °C), 1 μm (1100 °C) and 6 μm (1500 °C), respectively. The corresponding reducing magnitude of pore size is 98.5%, 83.3% and 33.3%. The HMOR of castables fired at 1500 °C increased by 110% to 3.64 MPa. Furthermore, after three thermal shock cycles, the residual strength ratio of castables increased from 5.2% to 15.3%. A large amount of cross-distributed columnar mullite was formed between nano silica and α-Al 2 O 3 by the two-dimensional nucleation mechanism, which remarkably enhanced the high temperature properties. The penetration index reduced from 30.86% to 19.88%, suggesting that smaller pore size and higher viscosity had a great influence to the penetration process. [ABSTRACT FROM AUTHOR]

The fabrication of a shell on the surfaces of ferromagnetic particles has been proved to be an efficient approach to tailoring and improving the electromicrowave (EM) absorption. In this study, core–shell composites (FeCo@SiO 2 /TiO 2 , FeCo@SiO 2 @TiO 2) were designed and fabricated by facile hydrolysis reactions. In these novel composites, the combined effects of the characteristics of each component result in excellent properties. The FeCo core exhibits strong magnetic loss, and the SiO 2 /TiO 2 shell not only acts as an impedance matching medium, but also exhibits excellent dielectric loss. Moreover, the SiO 2 and TiO 2 can efficiently limit direct contact between FeCo particles and protect the FeCo core from oxidation at high temperature. The FeCo@SiO 2 , FeCo@TiO 2 , and FeCo@SiO 2 @TiO 2 absorbers exhibit enhanced EM absorption, with maximum reflection losses (RL max) of −38.49, −36.53, and −33.72 dB at thicknesses d of 2, 5, and 3 mm, respectively, compared to −19.23 dB for FeCo single particles (d = 5 mm). The improvement is due mainly to the improved impedance matching and multiple interfacial polarization. In particular, after annealing at 500 °C, the RL max values of the FeCo@SiO 2 , FeCo@TiO 2 , and FeCo@SiO 2 @TiO 2 absorbers are −25.41, −24, and −32.38 dB at thicknesses of 3, 3, and 5 mm, respectively, which are much higher than that of uncoated FeCo (−1.39 dB, d = 5 mm). These findings demonstrate that the fabricated FeCo-based core–shell structures can be good candidates for use as room- and high-temperature EM absorbers. [ABSTRACT FROM AUTHOR]

The effect of the particle size (50–325 mesh) and content (0–0.1 wt%) of metallic aluminum powder on the explosive spalling resistance of corundum-based refractory castables were investigated in this study based on air permeability, pore size distribution, heat release, fracture energy and microstructural analyses. The experimental results show that the addition of Al powder significantly improves their explosive spalling resistance. As observed, the explosive spalling resistance of the castables was mainly influenced by the permeability mechanism and the fracture energy. Permeable paths were generated in the microstructure of the sample during the overlapping period between the curing process and the H 2 gas forming one, derived from the Al–H 2 O reaction. The highest permeability level was obtained when 0.075 wt % of Al powder with size of 100 mesh was incorporated into the corundum-based refractory castables. At the same time, the fracture energy of the castable samples was increased accordingly. [ABSTRACT FROM AUTHOR]

In this work, β-Sialon of different morphologies was generated using in situ morphological regulation and simulation. Their effects on the thermo-mechanical properties of Al 2 O 3 -C refractories were then investigated. The results indicate that columnar, plate-like, and hexagonal prism β-Sialon were formed from specimens without additives, with Fe 2 O 3 as a catalyst, and with Ni as a catalyst, respectively. Transmission electron microscope (TEM) analysis results confirmed that the three morphologies of β-Sialon grow along with (110), (101), and (100), respectively. Density functional theory (DFT) results show that the addition of catalyst atoms could reduce the adsorption energy of gaseous Al 2 O on different crystal planes, which promotes the formation of β-Sialon. The formation of three different shapes of β-Sialon gave rise to materials with good mechanical strength. The cold modulus of rupture (CMOR) and cold crushing strength (CCS) of the specimen containing plate-like structure was slightly higher than those with a columnar and hexagonal prism, with maximum CMOR and CCS values of 27.2 MPa and 105.2 MPa, respectively. In addition, good thermal shock resistance was obtained due to the formation of β-Sialon; the residual strength ratio of the specimen with columnar β-Sialon was 78% after five thermal shock cycles, and those with plate-like and hexagonal prism reached 93% and 86%, respectively. [ABSTRACT FROM AUTHOR]

Due to the coarse temporal resolution of the best track databases for typhoons, some small-scale characteristics of typhoon motion have been neglected. In order to reveal the fine features of typhoon motion, the dense cloud within the radius of maximum wind (RMW) of mature typhoons, defined as a "cloud gyro" that simultaneously spins around its own rotational axis and precesses around the vertical axis, is approximated to a rigid body. Based on the principles of gyrodynamics, the derived mathematical model of a typhoon track indicates that typhoon movement is composed of translational motion governed by the steering flow and superimposed precessional motion that manifests as the inherent characteristics of typhoon tracks, especially with the external torque. High temporal resolution numerical simulation of a real case verifies the conclusion of this study, which is that the smaller the RMW, the larger the tangential wind speed or the larger the external torque, and the more obviously precessional motion manifests. [ABSTRACT FROM AUTHOR]

Iron-containing siliconboron carbonitride (SiBCN) ceramics with multiple heterogeneous interfaces were fabricated using the microstructural design and polymer-derived ceramics (PDC) approach. The characterization results revealed the in - situ generation of nanocrystals, including graphite, belt-like silicon nitride (Si 3 N 4), and silicon carbide (SiC) whiskers, in amorphous SiBCN matrix after annealing. At the same time, these dielectric lossy phases successfully constructed multiple heterogeneous interfaces and three-dimensional network structures. Consequently, the conductivity of the ceramics increased from 4.49 × 10−9 (annealed at 800 °C) to 0.67 × 10−4 S cm−1 (annealed at 1600 °C). The real part of permittivity improved from 4.57–3.36 (annealed at 800 °C) to 10.90–8.38 (annealed at 1600 °C) in the frequency range of 2–18 GHz. The formation of multiple heterogeneous interfaces caused interfacial polarization and increased the multiple relaxations, which ultimately led to a superior microwave absorption property with a minimum reflection loss (RL min) of −34.28 dB and an effective absorption bandwidth (EAB) of 3.76 GHz (8.64–12.4 GHz). [ABSTRACT FROM AUTHOR]

β-Sialon with whisker-like, columnar, and plate-shaped structures was successfully synthesized with Al 2 O 3 –C refractory compositions. In the presence of a catalyst, the preferential growth face of columnar β-Sialon was (100), whereas plate-like β-Sialon preferred (101) and (111). DFT calculations demonstrated that the SiO adsorption energy on the (100), (101), and (111) faces of β-Sialon crystal were –34.95, –52.88, and –45.08 eV, respectively. Therefore, the (101) and (111) faces were more stable in Al-rich β-Sialon. With the increase in catalyst content, the Si-rich Si–Al–O–N liquid phases, which contributed to the generation of columnar β-Sialon, were converted into the Al-rich Al–Si–O–N system that was conducive to the formation of plate-like β-Sialon. Compared to the sample without the catalyst, the CMOR and HMOR of the specimen were increased by 45.07% and 60.47%, respectively, with the addition of Fe 2 O 3. This was attributed to the formation of β-Sialon with a one- or two- dimensional shape. [ABSTRACT FROM AUTHOR]

In this paper, the effects of the matrix pore structure on the strength and corrosion resistance of corundum castables are reported. Pore diameters of castables fired at 110 °C could be decreased from 550 nm to 72 nm when 4% Al 2 O 3 -SiO 2 gel powder was added. The pore diameter of the castables decreased from 850 nm to 500 nm after firing at 1100 °C, but increased from approximately 2 μm–8 μm after firing at 1500 °C. The strength of castables fired at 1500 °C increased remarkably with the addition of Al 2 O 3 -SiO 2 gel powder. A maximum cold modulus of rupture (CMOR) of 62.34 MPa was obtained when 4% Al 2 O 3 -SiO 2 gel powder was added. After slag corrosion, the penetration index fell from 16.6% to 4%, suggesting that a homogeneous pore size distribution and a smaller pore size played an important role in improving the penetration resistance. [ABSTRACT FROM AUTHOR]

The mechanical properties, thermal shock resistance, and microstructure evolution of corundum spinel castables with different nano‐alumina contents were investigated. The results show that the addition of nano‐alumina has advantages on the microstructure evolution and properties of castables. An optimum nano‐alumina amount is 2 wt%. When nano‐alumina addition changes from 0 to 2 wt%, the cold modulus of rupture (CMOR) and cold compressive strength (CCS) improved by 69.7% and 78.1% after firing at 1100°C, respectively. The CMOR and CCS increased by 42.5% and 35.2% after firing at 1500°C, respectively. Meanwhile, the hot modulus of rupture (HMOR) was enhanced by 21.5% to 13.4 MPa. The retained Young's modulus values of castables were improved from 49.6% to 59.6% after eight thermal shock cycles. Furthermore, the HMOR and the retained Young's modulus values of castables slightly reduced when nano‐alumina content up to 3 wt%. XRD, DSC, SEM, and EDS analyses revealed that the addition of nano‐alumina leads to the formation of calcium dialuminate (CaO·2Al2O3) at 1100°C and it is beneficial to the formation of more platelet hibonite (CaO·6Al2O3) at 1500°C. As a result of using nano‐alumina with large surface area, the solid phase sintering of the nanoscale particles can occur at lower temperatures. Moreover, the mechanical properties and thermal shock resistance of the castables were improved remarkably. [ABSTRACT FROM AUTHOR]

In this work, we present a simple design of a compact and miniaturized wideband bandpass filter (BPF) based on substrate integrated waveguide (SIW) and microstrip line. Through the order extension, the filtering effect and the order of the Chebyshev response of the designed BPF can be indirectly controlled by preserving square notches (SNs) on the SIW. By introducing one or two SNs in the SIW structure, the resonance frequencies of different modes can be controlled, thus achieving dual- and tri-mode BPFs with wideband and low insert loss. The working principle of the designed BPFs was illustrated by modal analysis, field distribution, and equivalent circuit theory. Based on this, the dual- and tri-mode BPFs with center frequencies of 6.8 and 7 GHz were designed and demonstrated numerically. Further experimental results indicate that the proposed tri-mode BPF has low insertion loss (0.25 dB), compact size (0.27λg2), and wideband bandwidth (60%). In addition, the tri-mode BPF achieves a broadband out-of-band rejection of 1.5f0 (f0 is the center resonance frequency) below the −10 dB level, making it highly promising for various applications in related fields. [ABSTRACT FROM AUTHOR]

Abstract Columnar β-Sialon bonding phases were in situ synthesised in Al 2 O 3 -C refractory composites and their growth mechanism was simulated based on first-principles calculations. The experimental results indicated that the addition of Fe 2 O 3 as a catalyst accelerated the transformation of Si 3 N 4 to β-Sialon, resulting in a well-developed columnar structure. The (100) facet was the primary surface for crystal growth during the transformation process of Si 3 N 4 into β-Sialon. According to first-principles calculations, the surface energy of the (100) facet decreased greatly due to the substitution of (Si, N) pairs with (Al, O). The catalyst could promote the adsorption of gaseous phases on the (100) facet of Si 3 N 4 and decreased the gas adsorption energy of both SiO and Al 2 O. Owing to the presence of in situ synthesised columnar β-Sialon bonding phases, the residual crushing strength of Al 2 O 3 -C refractory composites after 5 thermal shock cycles increased by 25.1%. [ABSTRACT FROM AUTHOR]

Al2O3–SiC–C composites were prepared using tabular corundum, ball pitch and silicon carbide as the main raw materials. The carbon nanotubes (CNTs) and SiC whiskers (SiCw) were in situ synthesized and their effects on the thermo–mechanical properties of Al2O3–SiC–C composites have been studied. The experimental results indicated that the high yield of SiCw and CNTs with large aspect ratio could be obtained due to addition of Ni(NO3)2·6H2O as catalyst in the composites. The cold modulus of rupture values were increased by 24% to 7.2 MPa, and the flexural modulus was increased from 19 GPa to 24 GPa. Additionally, the hot modulus of rupture reached a maximum value of 3.6 MPa, which presented a 71% increase over that of composites without catalyst. After three thermal shock cycles, the residual cold crush strength was improved from 57.1% to 76.9%. It is believed that the enhancement in the thermo‐mechanical properties of Al2O3–SiC–C composites could be attributed to the reinforcement effect of SiCw and CNTs. [ABSTRACT FROM AUTHOR]

Abstract Fe-Mo catalyst with different molar ratios (1:0, 1:0.5, 1:1, 1:2, 1:3) were prepared by chemical co-precipitation method, and they were added to phenolic resin as catalysts. The microstructure and physicochemical properties of catalyst and crystalline carbon after phenolic resin pyrolysis were characterized by XRD, SEM, FT-IR, XPS and TEM. The results showed that the Fe/Mo molar ratio played a significant role in the graphitization of phenolic resin and the morphology of carbon nanotubes. The graphitization of the phenolic resin first increased and then decreased with the addition of Mo. When the Fe/Mo molar ratio was 1:2, the phenolic resin achieved the highest graphitization, and the formed carbon nanotubes had the highest crystallinity. The Fe atoms were in an electron-deficient state due to the electrons transferring from Fe to Mo, which enhanced the hydrocarbon compounds absorption on the surface of catalyst. And Mo was carbonized by carbon atoms to form α-MoC 1-x , and then decomposed into β-Mo 2 C and graphite carbon, obtaining carbon atoms orderly arrangement and carbon nanotubes. Therefore, both the grain size and electron structure of catalyst significantly affect the catalytic properties of Fe-based catalyst. Graphical abstract Image 1 Highlights • The addition of Mo significantly increases the dispersibility of the catalyst. • Part of the electron transfer from Fe to Mo is that Fe is in an electron-deficient state. • A molar ratio of iron to molybdenum of 1:2 shows the best catalytic performance. • Conversion of MoC 1-x to Mo 2 C increases the diffusion of carbon atoms in the catalyst. [ABSTRACT FROM AUTHOR]

Abstract A study of non-oxide bonding phases formed in situ by adding La 2 O 3 to Al 2 O 3 -C refractories, and their influence on the thermo-mechanical properties, is presented. Calculations of the thermodynamics of the Al-Si-O-C-N system were thoroughly explored. Phase assemblage and microstructure were analyzed by means of X-ray diffraction and scanning electron microscopy. The results were that β-Sialon (Si 3 Al 3 O 3 N 5) and 15R-Sialon (SiAl 4 O 2 N 4) formed during sintering at 1400 °C. In addition, the presence of the rare earth oxide, La 2 O 3 , promotes columnar β-Sialon formation in a plate-like grain morphology, and this can improve the in situ synthesis of 15R-Sialon. The non-oxide bonding phases give rise to specimens with excellent strength and toughness. Increasing the La 2 O 3 content from 0 wt% to 0.6 wt% enhanced the cold modulus of rupture and the cold crushing strength of the specimens fired from 31.1 MPa to 34.6 MPa, and from 101.3 MPa to 113.8 MPa, respectively. Meanwhile, the displacement was increased by 68% to 0.32 mm. The generation of plate-like β-Sialon and 15R-Sialon also had a positive effect on the hot strength and thermal-shock resistance. The hot modulus of rupture of the specimens fired improved by 21% compared to specimens without La 2 O 3. After three thermal-shock cycles, the residual strength ratios of the specimens fired were above 88%. [ABSTRACT FROM AUTHOR]

Abstract The metaheuristic optimization methods have been widely used in complex composite material design. However, it is still difficult to apply these methods to complicated problems due to expensive cost of evaluations. Therefore, to reduce the expensive cost of finite element (FE) analysis in the composite laminate optimization problems, the surrogate assisted optimization (SAO) method has been well developed. However, considering the low accuracy of surrogate model for complicated cases, the SAO is always difficult to converge to the global optimum. In this study, a fast and accurate solver, the reanalysis algorithm is extended to vibration problem and integrated to improve the efficiency of metaheuristic optimization of composite laminates instead of surrogate model. In the proposed method, the shifting method is used in each iterative step. To validate the performance of suggested method, several numerical examples are presented. The results demonstrate that reanalysis assisted particle swarm optimization (RPSO) is much more efficient for free vibration problems of composite laminates than the PSO. Moreover, such strategy can be extended to other metaheuristic algorithms easily. [ABSTRACT FROM AUTHOR]

A series of novel niobia/carbon composites were synthesized by hydrothermal method following by carbonization with niobium tartrate and glucose as precursors, and used in the conversion of glucose and cellulose to 5-hydroxymethylfurfural (HMF). These catalysts were characterized by XRD, SEM, TEM, N 2 adsorption/desorption, NH 3 -TPD and Py-FTIR techniques and the results showed that the Nb/C catalysts were agglomerated particles, with weak to medium acid strength and suitable Brønsted/Lewis acid sites. When used in the hydrolysis and dehydration of cellulose, as high as 53.3% yield of HMF was achieved over Nb/C-50 catalyst at 170 °C for 8 h, accompanied with 24.5% glucose, with the total conversion of cellulose, indicating the high carbon yield and excellent activity. Furthermore, this catalyst showed excellent recyclability and its catalytic activity still maintained after 8 cycles. [ABSTRACT FROM AUTHOR]

In this paper, submicron spinel-containing calcium aluminate (SP-CA) cements were prepared at temperatures of 1200 °C (RA12), 1300 °C (RA13), and 1450 °C (RA14) using reactive alumina, magnesium hydroxide, and calcium carbonate as raw materials. The microstructural characteristics and high temperature properties of refractory castables bonded by SP-CA cement were investigated. The results indicated that the mineralogical compositions of SP-CA were spinel (MgAl 2 O 4 , MA) and CaAl 2 O 4 (CA). The spinel phases presented no definite borders or shapes, with average size ranging from 0.1 μm to 1.2 µm at different sintering temperatures. After heating alumina-spinel castables, the submicron spinel particles bonded with corundum and hibonite (CA 6 ) grains could strengthen the castable body. However, the large sized (< 88 µm) spinel did not form links between spinel and alumina in the castable with added preformed spinel (castable AS). Submicron spinel can decrease the pore sizes of refractory castables from 2 µm to 0.5 µm. Extended finite element method (XFEM) calculations showed that smaller pores prevent stress concentration and result in increased deformation with limited crack propagation. Hence, large numbers of 0.5 µm pores can act as crack-stoppers to improve the thermal shock resistance of castables with added SP-CA cements. Thermal shock resistance tests showed that R '''' of castable RA12 was 39.7 m, which is significantly higher than that of castable AS (19.8 m). The corrosion rate of castable RA12 was 5 mm 2 /min, which is significantly lower than that of castable AS (7.4 mm 2 /min). Small pore size and submicron spinel played relevant roles in corrosion behavior. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acidity adjustable Nb-SBA-15 with 2D hexagonal-ordered structure was synthesized. • Nb-SBA-15 is an high effective catalyst for the production of HMF from carbohydrate. • Nb-SBA-15 performs good hydrothermal stability in glucose conversion. • Nb species in SBA-15 framework and the mononuclear NbO 4 are the main active sites. 5-hydroxymethyl furfural (HMF) is a bio-based platform chemical with high potential. The as-synthesized Nb-SBA-15 catalysts with mesoporous structures showed high catalytic performance for the conversion of carbohydrates to HMF in a "one-pot" process using biphasic conditions of THF/H 2 O-NaCl as the solvents. Nb-SBA-15 catalysts with different Si/Nb ratios were characterized by analytical techniques such as XRD, elemental analysis, SEM, TEM, N 2 adsorption, NH 3 -TPD UV–vis DRS, Raman and Pyridine-FTIR. It was found that the acidity of Nb-SBA-15 catalysts could be tuned by modifying addition amount of niobium. The effects of reaction conditions, including temperature, time, and catalyst loading, on the conversions of carbohydrates and the yields of HMF were also investigated. The studies showed that Nb-SBA-15-40 catalysts which Si/Nb ratio is 40 gave the best yields of HMF due that Nb-SBA-15-40 had more niobium species in the SBA-15 silica framework and the mononuclear tetrahedral NbO 4. Under the optimized conditions, the yield of HMF could reach 61.8% at 93.5% glucose conversion and 50.7% at 94.0% cellulose conversion, respectively. Moreover, its catalytic performance was largely retained after 10 recycles in glucose conversion reaction vindicating its good catalytic stability. [ABSTRACT FROM AUTHOR]

Designing nanocomposite with multi-level interfaces is an effective approach to improving the microwave absorbing capability of materials. In this study, the urchin-like multiple core-shelled Co/CoS 2 @NC@MoS 2 composites (CCM) are designed and fabricated by high-temperature pyrolysis and solvothermal process, where the structure and phase composition are affected by the migration of Co. Abundant interfaces in the multiple core-shelled structures favor the polarization relaxation loss, defects of MoS 2 and nitrogen doping carbon (NC) matrix induce the dipole orientation polarization loss. The CCM composite exhibits excellent microwave absorption with the strongest reflection loss (RL) of − 43.9 dB. Meanwhile, the broadest effective absorption bandwidth (EAB, RL<−10 dB) is 4.4 GHz with a thickness of 1.5 mm. Besides, with the thickness of 1.0–3.5 mm, all peaks of RL min < −20 dB (99 % absorptivity). It is believed that this work can provide an effective strategy for the design of tunable multi-interface nanostructures to regulate microwave absorption. • The urchin-like multiple core-shelled Co/CoS 2 @NC@MoS 2 composites (CCM) are fabricated. • The reactivity of Co under the pyrolysis temperature could affect the structure and phase composition. • The intrinsic loss of CCM is dominated by the polarization relaxation loss. • The effective absorption bandwidth is 4.4 GHz with a thickness of 1.5 mm. [ABSTRACT FROM AUTHOR]

The conversion of glucose and selectivity into 5-hydromethylfurfural (HMF) were investigated over various silica-alumina composite (AlSiO) catalysts. The type, amount, and strength of the acidic sites were characterized by using NH3 temperatureprogrammed desorption and FTIR spectroscopy and then correlated to the catalytic conversion of glucose into HMF to provide a quantitative relationship between the acidity and product selectivity. Lewis acid sites played an important role in glucose conversion, which can enhance the isomerization of glucose to fructose, whereas Brønsted acid sites had a detrimental effect. HMF selectivity had an almost linear relationship with the weak/total Lewis acid ratio (L*/L), indicating that weak Lewis acids could promote formation of HMF. The medium-tostrong Lewis acid sites can enhance the formation of undesired byproducts (levulinic acid, humins). The Brønsted to Lewis acid ratio (B/L) had an influence on the HMF selectivity; at similar L*/L ratios, volcano curves were obtained with the increase of the B/L ratio, but the influence was not as great as that of the L*/L ratio. Nb-doped AlSiO catalysts were prepared and used in the conversion of glucose into HMF, which also confirmed the above findings. Under the optimized conditions, the HMF selectivity can reach 71% at 92.6% conversion of glucose with no clear decline after four catalytic cycles. [ABSTRACT FROM AUTHOR]

Low-carbon Al 2 O 3 -C refractory samples were prepared from raw materials of tabular alumina, reactive alumina powder, flake graphite and carbon black. Silicon powder and metallic Al powder were used as additives and phenol resin was used as binder. The effects of nitrogen partial pressure and firing temperature on microstructural evolution and the thermo-mechanical properties of low-carbon Al 2 O 3 -C refractories were investigated. The thermodynamic calculations for Al–Si–O–C–N systems suggested that SiC, AlN and β-Sialon could be stable under different nitrogen partial pressures. The experimental results showed that short columnar AlN and SiC whiskers were formed at 1200 °C. The aspect ratio of AlN was higher and SiC production become larger with nitrogen partial pressure increasing. Two-dimensional flaky β-Sialon could be generated as the nitrogen partial pressure increased to higher than 0.11 MPa at 1400 °C. Due to the formation of SiC whiskers and β-Sialon, the cold modulus of rupture and the cold crushing strength were improved from 12.8 MPa to 19.3 MPa and from 57.3 MPa to 74.7 MPa, respectively. The load displacement could be increased by 62% to 0.59 mm. At the same time, the maximum values of flexural modulus and hot modulus of rupture reached 4.2 GPa and 13.2 MPa, respectively. After three thermal shock cycles, the CCS of refractories containing the SiC whiskers and β-Sialon only decreased by 6.2 MPa. The in situ formation of SiC whiskers and β-Sialon could greatly enhance the thermo-mechanical properties of low-carbon Al 2 O 3 -C refractories. [ABSTRACT FROM AUTHOR]

Two kinds of hexagonal aluminum honeycombs are tested to study their out-of-plane crushing behavior. In the tests, honeycomb samples, including single hexagonal aluminum honeycomb (SHAH) samples and two stack-up combined hexagonal aluminum honeycombs (CHAH) samples, are compressed at a fixed quasistatic loading rate. The results show that the inserting process of CHAH can erase the initial peak stress that occurred in SHAH. Meanwhile, energy-absorbing property of combined honeycomb samples is more beneficial than the one of single honeycomb sample with the same thickness if the two types of honeycomb samples are completely crushed. Then, the applicability of the existing theoretical model for single hexagonal honeycomb is discussed, and an area equivalent method is proposed to calculate the crushing stress for nearly regular hexagonal honeycombs. Furthermore, a semiempirical formula is proposed to calculate the inserting plateau stress of two stack-up CHAH, in which structural parameters and mechanics properties of base material are concerned. The results show that the predicted stresses of three kinds of two stack-up combined honeycombs are in good agreement with the experimental data. Based on this study, stress-displacement curve of aluminum honeycombs can be designed in detail, which is very beneficial to optimize the energy-absorbing structures in engineering fields. [ABSTRACT FROM AUTHOR]

In this paper, the alumina-based refractory castables were prepared using calcium aluminate cement (CAC) as binder. The phase composition and microstructural evolution of the castable samples during the heating process were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), differential thermal analysis (DTA), and thermal expansion analysis. The relationship between the microstructural characteristics of castables and the properties of elastic modulus was investigated. The results showed that, after the castables were cured at room temperature for 24 h and dried at 110 °C for 24 h, the main phases present after hydration were Al 2 O 3 , C 3 AH 6 , and AH 3 . C 3 AH 6 and AH 3 would be transformed into C 12 A 7 and AlO(OH) or Al 2 O 3 , as temperature increased from 110 °C to 800 °C, the microcrack caused by decomposition of the hydrates will led to the lower values of both the elastic modulus and strength of the castable samples. From 900 °C to 1000 °C, CA was recrystallized through the reaction between C 12 A 7 and A, resulting in an increase in elastic modulus and strength. Between 1100 °C and 1200 °C, CA 2 would be formed, which resulted in a volume expansion of the material and a slight increase in elastic modulus. Finally, the CA 6 phase was formed as the temperature increased to 1400 °C. The enhancement of the strength and elastic modulus of the castable samples could be attributed to their strong interlocking bonds between platelet CA 6 and matrix particles at high temperature. [ABSTRACT FROM AUTHOR]

This study investigated the effect of the sintering temperature on the microstructural evolution and properties of Al 2 O 3 –C refractory samples, which were prepared using corundum, flake graphite, reactive alumina, Al and Si powders. The phenolic resin and nanometallic Ni were respectively applied as the binder and catalyst. The results indicate that hexagonal AlN particles, generated from the reaction of Al–N 2 in Al 2 O 3 refractories at 1000 °C, could transform into whiskers at 1200 °C. By increasing the sintering temperature to 1400 °C, a large number of plate-shaped β-Sialon could be generated. Under the action of Ni catalyst, the β-Sialon phases in refractories grew preferentially toward the crystalline facets (210) and (011) of AlN crystal and formed the plate-shape structure. When plate-shaped β-Sialon formed, the cold crushing strength (CCS) and cold modulus of rupture (CMOR) increased from 90.57 MPa to 148.67 MPa and from 22.83 MPa to 33.02 MPa, respectively. After two thermal shock cycles, the CCS of the refractories containing the plate-shaped β-Sialon had only decreased by 4.5 MPa. Thus, the in situ formation of plate-shaped β-Sialon could significantly improve the thermal shock resistance of Al 2 O 3 –C refractories. [ABSTRACT FROM AUTHOR]

The spalling and corrosion during the thermal cycles are the main causes of the damages observed in Al 2 O 3 SiC C castable composites that are used in molten-iron system. Using the catalyst of nano Ni and ball pitch in the matrix, Al 2 O 3 SiC C castable composites were prepared with the anti-oxidant addition of silicon. The results indicate that the high temperature of the Al 2 O 3 SiC C castable composites can be increased by above 42%, and the thermal shock resistance can be enhanced by above 20% because the ball pitch is carbonized and releases C x H y vapor, which can be pyrolized to carbon atoms and subsequently deposited into carbon fibers under the catalyst action. The starting temperature of carbon fiber growth is approximately 900 °C, and their diameter and aspect ratio can increase with the rising temperature. The in-situ generation of carbon fibers in Al 2 O 3 SiC C castable composites can significantly improve the fibers’ thermo-mechanical properties. [ABSTRACT FROM AUTHOR]

Herein, an ideal metamaterial absorber with broadband, ultrathin, and wide incidence angle is proposed. The absorption unit of the proposed metamaterial absorber consists of two double rings. And, eight chip resistors are loaded between them to increase the absorption bandwidth. It is showed in the simulation results that the structure absorbs more than 90% in the range of 8.6–17.4 GHz at vertical incidence. The total thickness of the absorber is 2.4 mm (0.069 λL), where λL is the lowest‐absorption frequency, smaller than the absorber structure of the same type of bandwidth. To understand the broadband absorption performance of this absorber, the effects of design parameters such as substrate thickness and resistive resistance are investigated. In addition, herein, to investigate the absorption mechanism of this absorber, the normalized impedance, electric field distribution, and surface current density are demonstrated. Finally, the absorber is fabricated and measured at vertical incidence, and the experimental results are in good agreement with the simulation results. [ABSTRACT FROM AUTHOR]

ATS -type zeolite is used to be known as aluminophosphate or borosilicate. Its aluminosilicate analog was supposed to be a promising solid acid material, which is still of great challenges to synthesize directly. Herein, we report a new zeolite, SCM-39, as the first directly synthesized ATS aluminosilicate, using commercially available 4-pyrrolidinopyridine as OSDA. SCM-39 exhibits great hydrothermal stability and possesses a large amount of acid sites. In comparison with MOR zeolite, it showed better catalytic performances in the disproportionation of toluene and self-condensation of cyclohexanone. [Display omitted] • SCM-39, a novel ATS -type aluminosilicate zeolite, was directly synthesized. • 4-pyrrolidinopyridine was used as the structure-directing agent. • SCM-39 possesses ultra large acid amount with high hydrothermal stability. • SCM-39 shows good performances in disproportionation of toluene. [ABSTRACT FROM AUTHOR]

NiCoCrAlYSi coatings were prepared on the surface of nickel-based high-temperature alloys (Inconel 625) by laser cladding (LC) technique, and then the surface was modified by high current pulsed electron beam (HCPEB). The microstructural results indicate that metallurgical defects on the original surface, including micropores and elemental segregations were eliminated, and a remelted layer consisting of high density of cross slips and nanostructures was obtained. High-temperature oxidation resistance at 900 °C, 1000 °C and 1100 °C of the original coatings was investigated. When oxidized at 900 °C for 100 h, the original coating followed the linear growth law, and the TGO was mainly consisted of Al 2 O 3. When oxidized at 1000 °C and 1100 °C for 100 h, the original coating followed the parabola law, and the TGO existed in a double-layer structure. After HCPEB irradiation, a rather stable, continuous, and slow-growing α-Al 2 O 3 was formed on the surface after oxidation for 100 h at 1100 °C. The kinetic curves show that the growth rate of the TGO of the irradiated coatings was reduced by 43.9%, and the thickness was effectively decreased compared with the original sample. Thus, HCPEB technique is proved to be an effective method to improve the service life of laser cladding coatings. [Display omitted] • Microstructures and oxidation behavior of NiCoCrAlYSi laser cladding coating was investigated. • Cladding coatings presented different oxidation rate and growth behavior at different temperatures. • HCPEB technique was used to further improve the microstructures and properties of cladding coating. • Restructured surface promoted the formation of a protective α-Al 2 O 3 layer at 1100 °C. • HCPEB technology is an effective way to improve the high-temperature service life of cladding coatings. [ABSTRACT FROM AUTHOR]

In order to reduce the sintering temperature and improve the mechanical properties of B4C ceramics, ZrB2 was formed in situ using the SPS sintering method with ZrO2 and B4C as raw materials. Thermodynamic calculations revealed that CO pressure affected the formation of ZrB2 at temperatures from 814 °C to 1100 °C. The experimental results showed that the ZrB2 grain size was <5 µm and that the grains were uniformly distributed within the B4C ceramics. With an increase in ZrO2 content, the Vickers hardness and flexural strength of the B4C ceramics first increased and then decreased, while the fracture toughness continuously increased. When the content of ZrO2 was 15 wt%, the Vickers hardness, fracture toughness and flexural strength of B4C ceramics were 35.5 ± 0.63 GPa, 3.6 ± 0.24 MPa·m1/2 and 403 ± 10 MPa, respectively. These results suggest that ZrB2 inhibits B4C grain growth, eliminates crack tip stress, and provides fine grain to strengthen and toughen B4C ceramics. [ABSTRACT FROM AUTHOR]

Abstract: Electromagnetic field (EMF) would speed up the corrosion of low carbon MgOories. Its influence mechanism will be investigated in this paper. The slag-resistance experiments of low carbon MgOories were carried out under the condition of an induction furnace and a resistance furnace, respectively. Low carbon MgOories with carbon of 6% (in mass) and a slag with the basicity (CaO/SiO2) of around 0.87 were used in the experiments. The slag line of MgOories corroded by the slag under the different conditions were analyzed by X-ray diffractometer (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). The results show that in the induction furnace with an electromagnetic field (EMF), no MgO dense layer exists in the interface. However, MgO dense layer could be formed in the interface without any EMF. The formation mechanism of MgO dense layer indicates that the EMF could enhance the solution of MgO and power of Mg (g) discharge. As a result, EMF restrains the formation of MgO dense layer. [Copyright &y& Elsevier]

Abstract: Using MgO–C refractories containing 6% carbon and the slag with a basicity (CaO/SiO2) of around 0.8, the melting slag resistance experiments of low carbon MgO–C refractories were carried out in induction furnace and resistance furnace, respectively. The microstructure of low carbon MgO–C refractories corroded by slag under the different conditions was analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDAX). The results show that in induction furnace having electromagnetic field (EMF), there are MgFe2O4 spinel with a little of Mn ions generated in the interfacial layer. Part of the solid solution is monticellite [CaMgSiO4] containing a little MnO and FeO. While under the condition of EMF free, there is not MgFe2O4 spinel in the interfacial layer and the solid solution is monticellite (CaMgSiO4). At a high temperature, EMF increases the diffusion coefficient of Fe2+/3+ ions, which displaces Mg2+ and forms MgFe2O4 with a little of Mn ions. There are MgAl2O4 spinel in the penetration layers under the conditions of both EMF and EMF free. EMF speeds up corrosion of low carbon MgO–C refractories. [Copyright &y& Elsevier]

Abstract: Carbonyl iron fibers were fabricated by magnetic-field-induced thermally decomposition of polymetallic carbonyl. Their fibrous morphology and magnetic properties were investigated by scanning electron microscope (SEM) and vibrating sample magnetometer (VSM) at room temperature respectively. The microwave characterizations of carbonyl iron fiber-filled foam composites were evaluated through arch test based on a network analyzer. The diameter and aspect ratio of the fibers have great influence on reflection loss. It was also found that carbonyl iron fiber-filled foam composites with small thinness and lightweight exhibit good microwave absorbing properties in the frequency of 8–18GHz, 26–40GHz and 75–110GHz. [Copyright &y& Elsevier]

B Background: b The most favorable long-term survival rate for hilar cholangiocarcinoma is achieved by an R0 resection. Anatomical left hepatectomy with caudate lobectomy could improve R0 resection and prognosis of patients. This patient was successfully treated with anatomical left hepatectomy combined with caudate lobectomy. [Extracted from the article]

Abstract: Fe55Ni45 fiber has been fabricated by magnetic-field-induced thermal decomposition of iron pentacarbonyl Fe(CO)5 and nickel tetracarbonyl Ni(CO)4. Fe55Ni45 fiber presents the face-centered-cubic (FCC) structure (γ-phase) characterized by X-ray diffraction (XRD) and fibrous morphology observed by scanning electron microscope (SEM). It is shown that with the increase of induced magnetic field, the diameter of the fiber can be increased from 5 to 8μm and its corresponding aspect ratio is decreased from 60–80 to 20–40. The complex permittivity and permeability of Fe55Ni45 fiber-filled composites are measured in x-band (8–12GHz) with the transmission and reflection waveguide method. The results show that Fe55Ni45 fiber of smaller diameter (5μm) and higher aspect ratio (60–80) exhibits higher complex permittivity and permeability. The reflection loss (RL) measurement reveals the thin composites filled with Fe55Ni45 fibers possess low RL value. [Copyright &y& Elsevier]