Effects of framework and Si/Al of Pt/zeolites on CO catalytic oxidation were investigated. CO conversion increased with decreasing pore size and increasing Si/Al. The optimized Pt/CHA with Si/Al of 17 showed the highe...
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Magnetic skyrmions are topologically nontrivial spin configurations that possess particle-like properties. Earlier research was mainly focused on a specific type of skyrmion with topological charge Q = −1. However, th...
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The high-temperature cubic phase of AgBiSe2 has been revealed to enable promising thermoelectric performance because of the high symmetry. In this work, it is shown that the cubic phase could be stabilized at room tem...
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Additive manu facturing(AM)is a promising material processing method which gains significant momentum in the aerospace and biomedical ***,the anisotropy in the mechanical properties of additively-manufactured material...
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Additive manu facturing(AM)is a promising material processing method which gains significant momentum in the aerospace and biomedical ***,the anisotropy in the mechanical properties of additively-manufactured materials is still poorly *** study was aimed at elucidating crystallographic feature-anisotropy-mechanical property relationship for a Ti-6Al-4V alloy manufactured via selective electron beam melting(SEBM).Abundantαlamellae with six variants were present inside the columnar prior-βgrains with a<100>fiber texture duringβ→αphase *** sixαvariants followed the Burgers orientation relationship of{110}_(β)//{0001}_(α)and<1-11>_(β)//<11-20>_(α).Multiple sub-variants in eachαvariant were observed for the first *** anisotropy in the mechanical properties was mainly related to the relative amount of sixα*** the horizontally-oriented samples had a lower yield strength,they exhibited a higher ductility and longer fatigue life than the vertically-oriented *** softening occurred at higher strain amplitudes,and cyclic stabilization sustained at lower strain *** crack mainly initiated from the specimen surface at lower strain amplitudes,while multiple crack initiation tended to occur at higher strain *** propagation was characterized by fatigue striations along with some secondary cracks.
To explore the crystal structure of the recently claimed room-temperature superconducting carbonaceous sulfur hydrides, we searched for ≈250000 structures over ≈800 stoichiometries at 300 GPa via advanced crystal st...
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To explore the crystal structure of the recently claimed room-temperature superconducting carbonaceous sulfur hydrides, we searched for ≈250000 structures over ≈800 stoichiometries at 300 GPa via advanced crystal structure searching and cluster expansion method. Only several metastable high-temperature superconductors were identified, whose structures can be classified into hydrogen-rich molecular crystals and low-level carbon-doped H3S-like structures by constructing the ternary phase diagram and simulating the electron-phonon interactions. The C–S–H molecular crystals are composed of CH4, SH6, and H2 molecules, where the superconductivity (with the highest superconducting critical temperature Tc is 156 K found in CSH48 at 300 GPa) is mainly contributed to by H2 units, implying their Tc values are unlikely to be higher than that of metallic molecular hydrogen (Tc of 242 K at 450 GPa). The highest Tc of low-level carbon-doped C–S–H compounds (up to 64 atoms in the primitive cell) at 300 GPa was estimated as 189 K for H3S0.917C0.083. Our results provide a comprehensive map between the crystal structure and superconductivity of carbonaceous sulfur hydride materials at high pressures.
Intermetallic Ti-45Al-8Nb-(W,B,Y)(at.%)and Ti-46Al-5Nb alloys are directionally solidified at a constant growth rate of 30μm·s-1 using a Bridgman type *** quenched microstructures and lengths of different phase ...
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Intermetallic Ti-45Al-8Nb-(W,B,Y)(at.%)and Ti-46Al-5Nb alloys are directionally solidified at a constant growth rate of 30μm·s-1 using a Bridgman type *** quenched microstructures and lengths of different phase regions were observed and measured after various growing times of 0-30 *** show that the phase transformations in different phase regions are mainly depending on the high temperature microstructure and the supercooling degree during quenching *** isothermal holding,the primary phase grows into the liquid phase,the dendrites change from equiaxed to columnar grains,and the length of the L+βphase region,L+β+αphase region and mushy zone varies,indicating that the entire directional solidification process can be described by a static equilibrium-nonequilibrium-dynamic equilibrium evolution *** addition,the gap between the original growth interface and front interface shows that the actual crystal growth rate is not equal to the drawing velocity during directional solidification.
Since the Industrial Revolution, anthropogenic activities have substantially increased the input of nitrogen (N) and phosphorus (P) into river basins, complexity by interplay with climate. This study analyzed the char...
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Alkaline water electrolysis is one of the primary drivers of hydrogen energy development, and anion exchange membranes (AEMs) play a dual role in ensuring both conductivity and safety. However, traditional polymer AEM...
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Graphene oxide (GO) membranes hold promise for selective CO2 adsorption over N2 due to their carboxyl groups, making them attractive for flue gas CO2 capture. However, challenges such as limited carboxyl content, flex...
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In this work, the effect of volumetric energy density (VED) on densification, microstructure and mechanical properties of SA508 Gr.3 steel produced by selective laser melting (SLM) was studied. As the VED gradually in...
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