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This paper investigates the effect of mesophase separation on the crystallization behavior of olefin block copolymers (OBCs) with different octene contents, which were synthesized by chain shuttling technology. Crystallization always occurs simultaneously but competitively with mesophase separation in OBCs. Because of the reason that the crystallization temperature is lower than the mesophase separation temperature for the OBCs, the mesophase separation can start first; large portions of the crystallizable hard blocks are confined in the mesophase-separated domains and could not contribute to the formation of radial lamellar stacks. In addition, the mesophase separation creates a stereo-hindrance effect; crystal lamellae could only grow through the interstitial space between the dispersed domains. As a result, large and compact crystals could not be formed. As the octene content increased in the sample, mesophase separation becomes more and more dominant, and the crystal morphology degrades sharply from spherulites to fragmentary lamella structures. It is found that increasing the annealing time during development of the mesophase-separated structure has a similar effect to increasing the octene content in the sample. However, all of the OBCs can form nearly the same crystalline morphology if the mesophase separation is suppressed, from which we can postulate that the nature of crystallization due to the crystallizable hard blocks in OBCs should be similar.

N-doped carbon black (NCB) supported Ni NPs exhibited higher activity than most Ni-based catalysts for selective HDO of vanillin at mild conditions, ascribing to higher reducibility, lower oxidation state of Ni NPs and enhanced spillover hydrogen of Ni to NCB.

A porous N-doped carbon-encapsulated CoNi alloy nanoparticle composite (CoNi@N−C) was prepared using a bimetallic metal−organic framework composite as the precursor. The optimal prepared Co 1 Ni 1 @N−C material at 800 °C exhibited well-defined porosities, uniform CoNi alloy nanoparticle dispersion, a high doped-N level, and scattered CoNi−N x active sites, therefore affording excellent oxygen catalytic activities toward the reduction and evolution processes of oxygen. The oxygen reduction (ORR) onset potential (E onset ) on Co 1 Ni 1 @N−C was 0.91 V and the halfwave potential (E 1/2 ) was 0.82 V, very close to the parameters recorded on the Pt/C (20 wt Pt%) benchmark. Moreover, it is worth noting that the ORR stability of Co 1 Ni 1 @N−C was prominently higher than that of Pt/C. Under the oxygen evolution reaction condition, Co 1 Ni 1 @N−C generated the maximum current density at the potential of 1.7 V (8.60 mA cm −2 ) and the earliest E onset (1.35 V) among all Co x Ni y @N−C hybrids. The Co 1 Ni 1 @N−C catalyst exhibited the smallest ΔE value, confirming the superior bifunctional activity. The high surface area and porosity, and CoNi−N x active sites on the carbon surface including the proper interactions between the N-doped C shell and CoNi nanoparticles were attributed as the main contributors to the outstanding oxygen electrocatalytic property and good stability.

Pyridinic nitrogen species in N-doped active carbon (xN-AC) are responsible for high activity of ring hydrogenation via the formation of a high percentage of electron-deficient Pd clusters.

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SAPO-34 and a novel SAPO molecular sieve with the RHO framework (designated as DNL-6) were synthesized using SAPO-5 (the denser phase) as the precursor and diethylamine (DEA) as the template. The entire transition process had been investigated by XRD, SEM, XRF, and NMR spectroscopy, which clearly revealed a solution-mediated transport mechanism attributed to the transformation from SAPO-5 precursor to SAPO-34 via oscillating phases [SAPO-5 (FD = 16.9 T/nm 3 ) => SAPO-34 (15.1) þ DNL-6 (14.5) f DNL-6 f SAPO-34]. The initially formed SAPO-34 was different from the final one in this transformation due to very different percentages of organic inclusions, indicating that the host-guest interactions played important roles for the phase selectivity during the synthesis. DNL-6, obtained as an intermediate of the transformation process, possessed good thermal stability, large microporous surface area (724 m 2 /g), and high micropore volume (0.36 cm 3 /g). Rietveld refinement showed that the framework of calcined DNL-6 had typical features of the RHO structure with a high symmetry [I23, a = 15.08429(9) Å], composed of a body-centered cubic arrangement of R cages linked via double 8-rings.