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Honeycomb cordierite coated with Cu-SSZ-13 zeolite is widely used for the selective catalytic reduction of NOx with NH3 (NH3-SCR) to reduce pollutants from vehicle emissions. However, conventional ...

The magnetic property of soft magnetic material is much dependent on its shape and anisotropy. In this work, the flake-like FeNi3 particles with 3D-network structure have been synthesized through hydrazine reduction at ambient condition in the presence of sodium lignosulfonate (SLS). The morphology and crystalline structure of the FeNi3 nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and energy dispersion spectrum (EDS). Both of the static and dynamic magnetic property of the FeNi3 particles were investigated. The results indicated that the morphology of the FeNi3 particles changed from spherical to flake shape with increasing SLS concentration or reaction time. The possible mechanism on the variation of particles morphology was proposed. The static magnetic property indicated that the flake-like FeNi3 showed a higher saturation magnetization and coercivity than that of the spherical particles. Dynamic magnetic performance showed that the flake-like FeNi3 particles also exhibited significantly higher real part ( μ ' ) and imaginary part ( μ " ) of the complex permeability than the spherical particles, especially in the range 0.6–1.0 GHz.

Pore defects have an important effect on the mechanical properties of graphene reinforced aluminum nanocomposites. The simulation study found that the pores affect the stress distribution in the matrix of the composite. Along the stretching direction, the larger stress appears on both sides of the pore, which is the source of potential cracks. It results in a sharp decrease in the mechanical properties of the composite. The higher the porosity, the greater the tendency of pore aggregation, and the risk of material failure is higher. The stress distribution in the matrix becomes more uneven as the pore size increases, and the large strain area around the pores also increases. Composites with circular pores have a higher strength than other irregularly shaped pores. The failure mode might be pore cracking, while composites with other shape pores are more prone to interface detachment. The simulation value of the stress-strain of the composite material is in good agreement with the experimental value, but the finite element simulation value is larger than the experimental value.

Anatase TiO2 anchored on graphene oxide (GO) can be synthesized through a one-step hydrothermal method. The as-formed nanohybrid has a unique hollow structure and a large surface area. More importantly, compared to the pristine TiO2 counterpart, TiO2@RGO composite materials as anodes in lithium-ion batteries have demonstrated a uniform and highly crystallized morphology and exhibited excellent cycling stability and rate capability of 352 mA h g−1 at 0.5C and 223 mA h g−1 at 5C after 100 cycles, indicating that the TiO2@RGO nanocomposite has promise in advanced Li-ion batteries. The improvement of electrochemical performance is assigned to the enhanced conductivity in the presence of GO in the TiO2@RGO nanocomposite, the anatase and TiO2–B mixed crystal phase of the hollow sphere TiO2@RGO nanocomposite, the small size of TiO2 particles in the nanocomposite, and the enlarged electrode/electrolyte contact area, leading to more active sites in TiO2@RGO.

The effects of aluminum (Al) on the microstructure, hardness and wear resistance of tungsten-copper (W-Cu) composites were investigated. The W-Cu composites were fabricated via mechanical alloying and spark plasma sintering. It is found that the Al dissolved in the metastable W-Cu alloy can act as an 'intermediary' to hinder the diffusion and phase separation process of Cu out of W during sintering, constructing an interpenetrating nanostructure where Al redistributes in W and Cu. Correspondingly, the hardness of composites increase from 463.4 HV30 to 512.05 HV30 due to Al dissolution and formation of the nanostructure, and their contributions to hardness variation of the original W and Cu regions were distinguished by nanoindentation. In addition, the wear volume was also reduced to less than a third of that of original W-Cu composites without Al addition due to the abundant interfaces and mechanical strengthening, which restricts the removal of W and propagation of cracks during the wear process.

It is necessary to evaluate the piezoelectric properties of PVDF film which can transfer and harvest the energy generated in human daily exercise. A new cantilever structure for evaluating the piezoelectric properties of PVDF film in a low frequency is presented in this paper. There are three aspects of this research have to be addressed. The first wok involves that we study the range of frequency and acceleration of human daily exercise. Then a new structure of resonating cantilever beam is designed. In addition, we do some simulation study with ANSYS, which optimizes the cantilever beam's dimension parameters in length, width and thickness in order to make its resonant frequency close to the frequency of human daily exercise. In the third aspect, the evaluation experiment is carried out whose result shows that the output voltage of PVDF film reaches 120 mV when the vibration frequency is 20.4 Hz and the vibration acceleration is 2 m/s 2 . The data proves the validity of the cantilever beam and PVDF film also has great piezoelectric properties under the condition of low vibration frequency.

3D‐printing technology is a promising approach for rapidly and precisely manufacturing zeolite adsorbents with desirable configurations. However, the trade‐off among mechanical stability, adsorption capacity, and diffusion kinetics remains an elusive challenge for the practical application of 3D‐printed zeolites. Herein, a facile “3D printing and zeolite soldering” strategy is developed to construct mechanically robust binder‐free zeolite monoliths (ZM‐BF) with hierarchical structures, which can act as a superior configuration for CO2 capture. Halloysite nanotubes are employed as printing ink additives, which serve as both reinforcing materials and precursor materials for integrating ZM‐BF by ultrastrong interfacial “zeolite‐bonds” subjected to hydrothermal treatment. ZM‐BF exhibits outstanding mechanical properties with robust compressive strength up to 5.24 MPa, higher than most of the reported structured zeolites with binders. The equilibrium CO2 uptake of ZM‐BF reaches up to 5.58 mmol g−1 (298 K, 1 bar), which is the highest among all reported 3D‐printed CO2 adsorbents. Strikingly, the dynamic adsorption breakthrough tests demonstrate the superiority of ZM‐BF over commercial benchmark zeolites for flue gas purification and natural gas and biogas upgrading. This work introduces a facile strategy for designing and fabricating high‐performance hierarchically structured zeolite adsorbents and even catalysts for practical applications.

Combining the advantages of the sol–gel method and solvothermal method, the single anatase phase of nano-titanium dioxide (TiO2) with high crystallinity had been prepared by means of the sol–solvent thermal improved process, in which butyl titanate was used as titanium source; anhydrous ethanol as solvent; concentrated nitric acid as inhibitor; and cationic surfactant cetyl trimethyl ammonium bromide (CTAB), anionic surfactant sodium dodecyl benzene sulfonate (SDBS), and nonionic surfactant polyethylene glycol (PEG) as dispersants. The analysis results of Brunauer–Emmett–Teller, scanning electron microscopy, and transmission electron microscopy characterizations indicated that CTAB-modified TiO2 with the optimum ratio had the most apparent dispersibility and the highest specific surface area compared with unmodified TiO2, SDBS-modified TiO2, and PEG-modified TiO2. At the same time, the photocatalytic degradation rate of methyl orange could be improved to 99.16%. It indicated that the modification effect of CTAB was significantly better than those of SDBS and PEG, which made the nanoparticles uniformly dispersed, resulting in higher photocatalytic activity.

The size effect of SiC particles on microstructures and mechanical properties of SiCp/Al composites produced by spontaneous infiltration technology was investigated. In this study, samples of SiCp/Al composites were fabricated using aluminum alloy ZL101 as the matrix material, and SiC particles with different sizes as reinforcement particles. The microstructures and micro-deformation of the samples were analyzed using optical micrograph, scanning electron microscope, energy dispersive spectrometer and WDW-50 respectively. The results show that the SiC particles can distribute uniformly in the aluminum matrix using the proposed method. Examing samples with different SiC particle sizes, the sample with the largest size of particle can significantly decrease the mechanical properties of the composites. Tensile strength of SiCp/Al composite increases along with a decrease in the size of SiC particles, but the ductility of the composites decreases. It was found that an obviously toughness fossa appeared in the fracture surfaces of composites, which indicated it behaviors tearing and plastic deformation characteristics.