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11.
Shao  Lingling  Zhou  Jiancheng  Zhang  Ming  Zhang  Qianyi  Wang  Nan  Zhu  Fengfan  Wang  Ke  Li  Naixu 《Research on Chemical Intermediates》2022,48(6):2489-2507

The one-pot catalytic conversion of cellulose into ethylene glycol (EG) is an attractive way of biomass utilization. However, low-cost, efficient, and stable catalysts are the premise and research challenges of industrial application. Herein, the magnetic recyclable W–Ni@C catalyst was synthesized by in-situ pyrolysis of Ni-MOFs impregnated with ammonium metatungstate. Compared with the Ni-W bimetallic catalysts prepared by the impregnation method and the sol–gel method, the W–Ni@C catalyst for cellulose hydrogenolysis reaction can achieve a higher ethylene glycol yield (67.1% vs 43.3% and 42.6%) and 100% of cellulose conversion rate. The uniformly dispersed Ni nanoparticles and abundant defective WOx were formed in a reductive atmosphere generated in pyrolysis of Ni-MOFs, which was indispensable for the hydrogenolysis of cellulose into EG. Besides, the hierarchical porous carbon derived from organic ligands in Ni-MOFs reduces the mass transfer resistance while confining Ni nanoparticles and WOx to prevent their leaching, effectively enhancing the stability of the W–Ni@C catalyst. Therefore, the remarkable catalytic performance, the simple and effective recovery method as well as satisfying stability would make W–Ni@C become a promising catalyst for the conversion of cellulose to EG.

Graphical abstract
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12.
Fiber-reinforced-concrete (FRC) mechanism refers short discrete fibers that are uniformly distributed and randomly oriented, which offers an effective way to improve the mechanical performance of concrete. In the design of supramolecular polymers, an analogous concept of FRC appears to have been considered very rarely-although fibrous structure has been frequently observed/generated during the supramolecular polymerization. In this work, we apply the alkane thermosets, octadecane (C18H38) and tetracosane (C24H50), taking the role of “concrete”, and the low-molecular-weight monomer with long alkyl chains as the essential “fiber” component, to fabricate the “fiber reinforced supramolecular polymer”. Very much like FRC mechanism in material science, the resulting fiber reinforced supramolecular polymer thus exhibit unusually high mechanical strength and stiffness, which is unprecedented in the conventional supramolecular strategy.  相似文献   
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Journal of Solid State Electrochemistry - A molecularly imprinted photoelectrochemical (PEC) cathodic sensor was developed for the detection of bovine serum albumin (BSA). The PEC sensor was...  相似文献   
14.
Chemistry of Natural Compounds - A new chamigrane sesquiterpene, antroalbol F (1), along with one known compound, acaciicolinol C (2), were isolated from cultures of the fungus Antrodiella...  相似文献   
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Naphthalene endoperoxides are known as convenient sources of singlet oxygen (O2, 1Δg), which is the major product of endoperoxide cycloreversion reaction. However, their potential as carriers of ground-state molecular oxygen (O2, 3Σg) similar to artificial oxygen carriers remains largely unexplored. This is due to the extreme reactivity and cytotoxic effects of the released singlet oxygen. We now report that a compound with a bimodular design, which incorporates an endoperoxide and an efficient physical quencher of singlet oxygen, 1,4-diazabicyclo[2.2.2]octane (DABCO), produces exclusively ground-state molecular oxygen. This result, coupled with the fact that oxygen release rates from endoperoxides are highly amenable to fine-tuning in a very broad range, and open to targeting by ligand attachment, raises the potential of these compounds far above any comparable chemical, or even biochemical sources. In cell culture experiments, we showed that the addition of the endoperoxide-quencher conjugate can enhance and sustain cell proliferation.  相似文献   
16.
An efficient catalyst-free, alternative method for the C–N bond formation reaction of alkyl electrophiles using formamides as the N-sources was achieved under mild conditions. The reaction possesses the advantages of a broad range of substrates scope and wide functional group tolerance. It should also be noted that this process was performed using the environmentally benign water as the sole solvent, and high yield can also be achieved in ten-gram scale.  相似文献   
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In nonrigid image registration, similarity measures including spatial information have been shown to perform better than those measures without spatial information. In this work, we provide new insight to the relationships among regional mutual information, regional probability distribution functions (PDFs) and global PDFs, and propose a novel nonrigid registration scheme with spatially weighted global probability distribution function (SWGPDF). Similarity measures based on SWGPDF (SWGPDFSM) are constructed. Three different spatial sub-region division methods are compared: the equally spaced sub-region (ESSR), the local binary pattern sub-region (LBPSR) and the gradient sub-region (GSR). The registration scheme applies B-spline based free form deformations (FFDs) as the transformation model. A Parzen window and linear interpolation are used to construct histograms. The SWGPDFSM registration scheme with ESSR space division is compared with the traditional global mutual information (gMI), the traditional global normalized mutual information (gNMI), regional mutual information and the SWGPDFSM with LBPSR or GSR space division. The test results show that SWGPDFSM scheme with ESSR space division outperforms the other schemes for elastically aligning images in the presence of big geometrical transformations, bias fields and illumination changes.  相似文献   
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We report a self‐propelled Janus silica micromotor as a motion‐based analytical method for achieving fast target separation of polyelectrolyte microcapsules, enriching different charged organics with low molecular weights in water. The self‐propelled Janus silica micromotor catalytically decomposes a hydrogen peroxide fuel and moves along the direction of the catalyst face at a speed of 126.3 μm s?1. Biotin‐functionalized Janus micromotors can specifically capture and rapidly transport streptavidin‐modified polyelectrolyte multilayer capsules, which could effectively enrich and separate different charged organics in water. The interior of the polyelectrolyte multilayer microcapsules were filled with a strong charged polyelectrolyte, and thus a Donnan equilibrium is favorable between the inner solution within the capsules and the bulk solution to entrap oppositely charged organics in water. The integration of these self‐propelled Janus silica micromotors and polyelectrolyte multilayer capsules into a lab‐on‐chip device that enables the separation and analysis of charged organics could be attractive for a diverse range of applications.  相似文献   
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