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The production of hydrogen from the aqueous-phase reforming (APR) of oxygenated hydrocarbons is promising. Herein, the performances of Pt loaded on NiAl2O4 spinel and γ-Al2O3 were investigated in the APR of methanol. The conversion of methanol and the yield of hydrogen over Pt/NiAl2O4 reached 99.9% and 95.7%, respectively. In comparison with Pt/γ-Al2O3 catalyst (26.5% and 23.3%, respectively), these values were enhanced by 4-fold. More importantly, Pt/NiAl2O4 had high stability with only 10% loss of its initial conversion after 600 h on stream. In situ diffuse reflectance infrared Fourier transform spectra (DRIFTS) of the APR of methanol revealed that the reaction underwent the dehydrogenation of methanol and the sequential water–gas shift (WGS) reaction. These two reactions were then investigated independently, in which Pt/NiAl2O4 showed more efficient performance than Pt/γ-Al2O3. Intensive characterization methods revealed that the chemical state of Pt played a pivotal role in the dehydrogenation of methanol to generate the adsorbed CO intermediate. For Pt/NiAl2O4 catalyst, the reduction of PtO x to metallic state Pt was easier because of the presence of the oxygen vacancy, leading to the higher catalytic performance in the dehydrogenation of methanol. Further studies with in situ DRIFTS-MS of WGS demonstrated a redox mechanism over Pt/NiAl2O4 catalyst, which was different from the associative route that occurred over Pt/γ-Al2O3 and made the WGS reaction faster. The addition of Ni (NiAl2O4 spinel) creates oxygen vacancies, giving WGS which underwent a redox route. This work presents the deep understanding into the pathway and mechanism in the APR of methanol and is expected to have important implications for the future development of APR catalysts.

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Lignin is constructed from methoxylated phenylpropanoid with plenty of hydroxys and methoxys. Its conversion to valuable products is extremely attractive but especially challenging without additional hydrogen sources. Herein we report a hydrogen-free production of 4alkylphenols directly from native lignin via self-reforming-driven depolymerization and hydrogenolysis over Pt/NiAl 2 O 4 . This is the first example of acquiring 4-alkylphenols from native lignin. Using this strategy, high yields of 4-alkylphenols, 17.3 wt %, were obtained from birch lignin. Reaction pathway and mechanism studies revealed that this strategy initiates from the reforming of aliphatic hydroxys, followed by the cleavage of C−O linkages, and ends via demethoxylation over Pt/NiAl 2 O 4 . Moreover, the subsequent aqueous phase reforming of the as-formed methanol accelerates the whole process. This strategy realizes the one-pot production of 4-alkylphenols from lignin by fully utilizing the structural hydrogen in lignin and H 2 O, providing a low-cost and safe method of lignin valorization.

Traditional injection and extraction devices often appear painful and cumbersome for patients. In recent years, polymer microneedles (MNs) have become a novel tool in the field of clinical medicine and health. However, the cost of building MNs into any shapes still remains a challenge. In this paper, we proposed hydrogel microneedles fabricated by high-precision digital light processing (H-P DLP) 3D printing system. Benefits from the sharp protuberance and micro-porous of the hydrogel microneedle, the microneedle performed multifunctional tasks such as drug delivery and detection with minimally invasion. Critical parameters for the fabrication process were analyzed, and the mechanical properties of MNs were measured to find a balance between precision and stiffness. Results shows that the stiffness and precision were significantly influenced by exposure time of each layer, and optimized printing parameters provided a balance between precision and stiffness. Bio-compatible MNs based on our H-P DLP system was able to execute drug injection and drug detection in our experiments. This work provided a low-cost and fast method to build MNs with 3D building, qualified the mechanical performance, drug injection, drug detection ability of MNs, and may be helpful for the potential clinical application.

The dependence of magnetotransport behaviors on A-site disorder induced by A-site cational size mismatch in ferromagnetic manganites is investigated by characterizing a series of samples with the same A-site cational mean radius ͗r A ͘ = 1.20 Å but different A-site ionic radii variance 2 = ͚ i x i r i 2 − ͗r A ͘ 2 , where x i and r i are the atomic fraction and ionic radii of i-type ions at A-site, respectively. It is revealed that the ground state transits from ferromagnetic metal to cluster-glass insulator upon increasing the variance 2 from 0.0003 for La 0.55 Ca 0.45 MnO 3 to 0.015 for Sm 0.55 ͑Ca 0.6 Ba 0.4 ͒ 0.45 MnO 3 , while the crystallographic structure and lattice constants of these manganites remain unchanged. Nevertheless, the increasing A-site disorder is believed to enhance the random local radial distortion of MnO 6 octahedra and suppress the ferromagnetic long-range order. In the manganites of high A-site disorder, the long-range ferromagnetic ordering is completely melted into the short-range magnetically ordered clusters and then the stepwise magnetization. With decreasing temperature, the short-range ordered clusters become frustrated at the frustrating point, below which a cluster-glass transition occurs due to the weak intercluster interaction.