Hollow carbon nanofibers with hierarchical porous shells were prepared by NaOH activation of the electrospinning SiCNO fibers, followed by carbonization treatment. By adjusting the carbonization temperature, porous hollow carbon nanofibers with different Brunauer−Emmett−Teller (BET) specific surface areas and total pore volumes are obtained, both of which are explored as electrode materials for supercapacitors. It was found that the obtained products (HCF800) possess the highest BET specific surface area of 2628.10 m 2 /g and the largest pore volume of 2.32 cm 3 /g when the carbonized temperature was designed at 800 °C, thus displaying the best supercapacitor performance. The electrochemical results in a three-electrode system show that HCF800 exhibits a high specific capacitance of 330.11 F/g as the discharge current density is 1 A/g and still maintains 65.3% of its original specific capacitance when the current density reaches 20 A/g. Moreover, in a twoelectrode system, HCF800 also exhibits an excellent specific capacity of 259.86 F/g at a current density of 1 A/g, marvelous cyclic stability with the specific capacitance retention of 95.3% even after 10,000 cycles, and a large energy density of 12.99 W h/kg at 1.0 A/g. Significantly, the supercapacitor performance of these porous hollow carbon nanofibers is also superior to that of many previously reported carbon materials, which proved them to be worthy candidates for high-performance electrode materials.

Mixed matrix membrane (MMM) structures and performances are greatly affected by the distribution of nanoparticles in the polymeric matrix. Until now, there has been little research on the effects of nanoparticle distribution states on polyacrylonitrile (PAN)‐based MMM structures and performances. In this paper, different intermolecular interactions between nanoparticles and PAN molecules were generated by in situ fabricated amino‐functionalized SiO2 and TiO2 nanoparticles to create absolutely different distribution states of nanoparticles in a PAN matrix. The results indicated that, due to the strong interactions between amino and cyano groups, SiO2 is distributed in the PAN membranes homogeneously, while most of the TiO2 migrates to the membrane's top surfaces or the walls of pores or even escape from the membranes during the nonsolvent index phase separation (NIPS) process. PAN‐TiO2 MMMs have more hydrophilic top surfaces, higher porosity, larger mean pore size, and stronger antifouling performances than pure PAN and PAN‐SiO2 membranes. The PAN‐TiO2 MMMs have an ultrahigh water flux of 1204.6 L/(m2 h), which is more than 44 times that of PAN membranes. And the good pore structures and hydrophilicity of the membranes derived from special interactions between in situ TiO2 nanoparticles and PAN molecules can give high‐performance PAN‐based ultrafiltration membranes a bright future. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47902.

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such as high-hardness/strength, excellent elasticity, and high compressibility. [1][2][3][4] Carbon nitride films, [5] pure carbon films, [6] and hydrogenated carbon films [7] containing these fullerene-like structures have been proved to possess excellent elastic recovery rate (85%, 80%, and 85%, respectively) and high hardness values (60, 53, and 19 GPa, respectively). In particular, hydrogenated fullerene-like carbon (FLC:H) films can also exhibit ultralow friction behaviors, which are desirable to minimize mechanical dissipation. These properties are essential for the application of these materials as protective coatings to engineering components. But the exact relationship between these properties and the fullerene-like structures is still unclear. The nanostructure of graphene sheets and the number of cross-linking sites between them may be two main structural factors determining these properties. Exploring the structureproperties relationship is crucial to effectively tailor these properties for potentially more applications. Some relevant studies have demonstrated that fullerene-like spheroids (FLS) encased in disordered graphene layers [4] and aligned carbon nanotube films [8] can display a lot of mechanical characteristics similar to those of architectured materials. Controlling the size, concentration, and connectivity of FLS or manipulating buckled morphologies of nanotube can tailor their mechanical properties. Thus, it is expected that FLC films may yield exceptional and tunable mechanical properties by controlling the nanostructure of graphene sheets. However, there are very few experimental reports on these issues, because designing and controlling the nanostructure of graphene sheets in FLC films remains a technical challenge.Recently a number of methods, such as ion beam-assisted deposition, molecular beam epitaxy, and plasma enhanced chemical vapor deposition (PECVD) have been developed for manufacturing high quality graphene-like materials. [9][10][11] It has been demonstrated that low-energy argon ions bombardment in these deposition systems is beneficial for the formation of graphene network. [12][13][14] Molecular dynamics simulations experiments also showed that low-energy (10-25 eV) argon ions bombardment could result in an increase in the number of graphitic rings and further enhance the graphene network growth. [13,15] The formation of curved graphene sheets (CGS) in magnetron-sputtered CN x films was mainly attributed to Hydrogenated fullerene-like carbon (FLC:H) films would be a widely used material with a unique combination of properties including high-hardness/ strength, excellent elasticity, and ultralow friction. The nanostructure of graphene sheets and the number of cross-linking sites between them may be two main structural factors determining these properties. Exploring the structure-properties relationship is crucial to effectively tailor these properties for potentially more applications. In this study it is demonstrated that FLC:H films can yield exceptional and tunable mec...

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In order to achieve hot processing products with expected microstructures, the construction of corresponding relationships between micro-evolution mechanisms and hot processing parameters is essential. In this study, such corresponding relationships of as-cast AlCu4SiMg alloy were constructed by double evaluating processing maps and Zener-Holloman (Z) parameter maps. Based on the stressstrain data obtained from a series of isothermal compression experiments, the processing maps of AlCu4SiMg alloy were constructed at the strain of 0.3, 0.5, 0.7 and 0.9 s-1. The processing maps revealed that the optimal hot deformation parameter windows corresponding to dynamic recrystallization (DRX) micro-evolution mechanism mainly appear at high temperature and moderate strain rate. On the other hand, the response maps of Z parameter at discrete strains were constructed, and the ideal processing windows were calibrated at the domains with relatively low lnZ-value. A phenomenon was found that the optimal deformation parameter windows identified by Z parameter are more conservative than those identified by processing map. By integrating processing maps and Z parameter maps, the optimal processing parameter windows corresponding to DRX micro-evolution mechanism for AlCu4SiMg alloy were finally obtained.