To achieve zero-carbon economy, advanced anode catalysts are desirable for hydrogen production and biomass upgrading powered by renewable energy. Ni-based non-precious electrocatalysts are considered ...as potential candidates because of intrinsic redox attributes, but in-depth understanding and rational design of Ni site coordination still remain challenging. Here, we perform anodic electrochemical oxidation of Ni-metalloids (NiP
, NiS
, and NiSe
) to in-situ construct different oxyanion-coordinated amorphous nickel oxyhydroxides (NiOOH-TO
), among which NiOOH-PO
shows optimal local coordination environment and boosts electrocatalytic activity of Ni sites towards selective oxidation of methanol to formate. Experiments and theoretical results demonstrate that NiOOH-PO
possesses improved adsorption of OH* and methanol, and favors the formation of CH
O* intermediates. The coordinated phosphate oxyanions effectively tailor the d band center of Ni sites and increases Ni-O covalency, promoting the catalytic activity. This study provides additional insights into modulation of active-center coordination environment via oxyanions for organic molecules transformation.
Emerging artificial enzymes with reprogrammed and augmented catalytic activity and substrate selectivity have long been pursued with sustained efforts. The majority of current candidates have rather ...poor catalytic activity compared with natural molecules. To tackle this limitation, we design artificial enzymes based on a structurally well-defined Au
cluster, namely clusterzymes, which are endowed with intrinsic high catalytic activity and selectivity driven by single-atom substitutions with modulated bond lengths. Au
Cu
and Au
Cd
clusterzymes exhibit 137 and 160 times higher antioxidant capacities than natural trolox, respectively. Meanwhile, the clusterzymes demonstrate preferential enzyme-mimicking catalytic activities, with Au
, Au
Cu
and Au
Cd
displaying compelling selectivity in glutathione peroxidase-like (GPx-like), catalase-like (CAT-like) and superoxide dismutase-like (SOD-like) activities, respectively. Au
Cu
decreases peroxide in injured brain via catalytic reactions, while Au
Cd
preferentially uses superoxide and nitrogenous signal molecules as substrates, and significantly decreases inflammation factors, indicative of an important role in mitigating neuroinflammation.
As consequence of the dual demands for pollution control and carbon (C) fixation in soils, Fe(II)-catalyzed mineral transformation may be a promising method to simultaneously immobilize heavy metals ...or organic matter (OM), but the underlying mechanisms remain unclear. Here, the synchronous sequestration mechanism of cadmium (Cd) and fulvic acid (FA) during Fe(II)-catalyzed the transformation ferrihydrite with C/Fe molar ratio of 0.21 were examined. Mineral phase analysis revealed that increasing the Fe(II) concentration (1–5 mM) favored the transformation of lepidocrocite and goethite to magnetite, and ferrihydrite transformation rate increased with increasing Fe(II) concentration. Color overlays and line profiles of elements depicted that Cd was dominantly adsorbed on the lepidocrocite and goethite surfaces. A positive correlation between the quantity of nonextractable Cd and magnetite further indicated that Cd may be sequestered by magnetite. Meanwhile, FA molecules were adsorbed on goethite surfaces and magnetite aggregates, and incomplete structure of lepidocrocite provide spaces for immobilizing C. Newly formed iron (Fe) (oxyhydr)oxides may immobilize Cd through surface binding, structural substitution, and physical encapsulation. The OM bound to the newly formed Fe (oxyhydr)oxides was rich in aromatic and carboxyl functional groups, which was beneficial for binding Cd, whereas the presence of Cd promoted the generation of nano pore spaces or defects and consequently enhanced FA sequestration. Therefore, Cd immobilization and FA sequestration can be synchronously achieved during the phase transformation. The findings provide a profound insight into various nanoscale mechanisms accounting for the fate of Cd and FA coupled with mineral transformation. The findings also are very helpful for developing strategies for simultaneously immobilizing heavy metals and C in soils.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Ultra‐uniform SnOx/carbon nanohybrids for lithium‐ion batteries are successfully prepared by solvent replacement and subsequent electrospinning. The resulting 1D nanostructure with Sn‐N bonding ...between the SnOx and N‐containing carbon nanofiber matrix can not only tolerate the substantial volume change and suppress the aggregation of SnOx, but also enhances the transport of both electrons and ions for the embedded SnOx, thus leading to high cycling performance and rate capability.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
Regenerable nanozymes with high catalytic stability and sustainability are promising substitutes for naturally-occurring enzymes but are limited by insufficient and non-selective catalytic ...activities. Herein, we developed single-atom nanozymes of RhN
4
, VN
4
, and Fe-Cu-N
6
with catalytic activities surpassing natural enzymes. Notably, Rh/VN
4
preferably forms an Rh/V-O-N
4
active center to decrease reaction energy barriers and mediates a “two-sided oxygen-linked” reaction path, showing 4 and 5-fold higher affinities in peroxidase-like activity than the FeN
4
and natural horseradish peroxidase. Furthermore, RhN
4
presents a 20-fold improved affinity in the catalase-like activity compared to the natural catalase; Fe-Cu-N
6
displays selectivity towards the superoxide dismutase-like activity; VN
4
favors a 7-fold higher glutathione peroxidase-like activity than the natural glutathione peroxidase. Bioactive sutures with Rh/VN
4
show recyclable catalytic features without apparent decay in 1 month and accelerate the scalp healing from brain trauma by promoting the vascular endothelial growth factor, regulating the immune cells like macrophages, and diminishing inflammation.
Urban environment is the place that human depends on to survive. The quality of urban design concepts will directly impact the change of urban environment. However, due to the lack of user ...interaction and clear information exchange between users and designers, it is difficult for users to understand urban design concepts, and sometimes even misunderstanding will be caused. Thus, the present paper seeks to improve users’ understanding of urban design concepts via available communication media and using useful presentation technology (VR with the integrated APS). In this research, we recruited 60 participants to view the script video (the running result of APS) or/and free navigate in the virtual environment of Tatsumi region, Tokyo Bay Zone, Japan. By studying the data of subjective feedbacks, we investigated how APS impacts participants’ cognition and evaluation of Sustainable Taches and Reactivate Space (STARS, the design concepts). Furthermore, qualitative interview was developed to further understand participants’ design concepts understanding and to verify whether VR with the integrated APS can improve users’ understanding of urban design concepts. Results from this research explains the future use of VR with the integrated APS technology as an efficient tool in urban design schemes presentation.
Two kinds of novel water-soluble ILs were synthesized and applied as lubricant additives in water-glycol. ILs, as the multifunctional and high efficiency additive, could drastically improve antiwear, ...friction-reducing and extreme pressure properties of water-glycol. SEM and EDS results indicated that the sample lubricated by PEG600MO phosphate-ammonium IL (P1) acquires higher active element content in the area with heavy wear, while that lubricated by PEG600MO phosphite-ammonium IL (P2) is relatively homogeneous on the worn surface with heavy and mild wear. L-edge XANES results showed that the tribofilm is composed of polyphosphate, and the increase of the polyphosphate chain length could improve the tribological properties. Additionally, the additive concentration, the rubbing time and the load could change the chain length of polyphosphate.
•Two kinds of water-soluble ionic liquids (ILs) with the same quaternary ammonium cation but different phosphite or phosphate anions were synthesized, which exhibits favorable water solubility and hydrolytic stability in water-glycol.•Water-soluble ILs with different anions showed distinct tribological properties.•SEM-EDS and L-edge XANES were applied comprehensively to clarify the lubricating mechanism of ILs as additives.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In multicellular organisms, receptor tyrosine kinases (RTKs) control a variety of cellular processes, including cell proliferation, differentiation, migration, and survival. Sprouty (SPRY) proteins ...represent an important class of ligand‐inducible inhibitors of RTK‐dependent signaling pathways. Here, we investigated the role of SPRY1 in cells of the central nervous system (CNS). Expression of SPRY1 was substantially higher in neural stem cells than in cortical neurons and was increased during neuronal differentiation of cortical neurons. We found that SPRY1 was a direct target gene of the CNS‐specific microRNA, miR‐124 and miR‐132. In primary cultures of cortical neurons, the neurotrophic factors brain‐derived neurotrophic factor (BDNF) and Basic fibroblast growth factor (FGF2) downregulated SPRY1 expression to positively regulate their own functions. In immature cortical neurons and mouse N2A cells, we found that overexpression of SPRY1 inhibited neurite development, whereas knockdown of SPRY1 expression promoted neurite development. In mature neurons, overexpression of SPRY1 inhibited the prosurvival effects of both BDNF and FGF2 on glutamate‐mediated neuronal cell death. SPRY1 was also upregulated upon glutamate treatment in mature neurons and partially contributed to the cytotoxic effect of glutamate. Together, our results indicate that SPRY1 contributes to the regulation of CNS functions by influencing both neuronal differentiation under normal physiological processes and neuronal survival under pathological conditions.
We found sprouty1 (Spry1) was a direct target gene of the central nervous system (CNS)‐specific microRNAs, miR‐124 and miR‐132. Our research implies that Spry1 participates in the regulation of CNS functions by influencing both neuronal differentiation under normal physiological processes and neuronal survival under pathological conditions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
Integrating nitrogen species into
sp
2
-hybridized carbon materials has proved an efficient means to improve their electrochemical performance. Nevertheless, an inevitable mixture of ...nitrogen species in carbon materials, due to the uncontrolled conversion among different nitrogen configurations involved in synthesizing nitrogen-doped carbon materials, largely retards the precise identification of electrochemically active nitrogen configurations for specific reactions. Here, we report the preparation of single pyrrolic N-doped carbon materials (SPNCMs) with a tunable nitrogen content from 0 to 4.22 at.% based on a strategy of low-temperature dehalogenation-induced and subsequent alkaline-activated pyrolysis of 3-halogenated phenol-3-aminophenol-formaldehyde (X-APF) co-condensed resins. Additionally, considering that the pseudocapacitance of SPNCMs is positively dependent on the pyrrolic nitrogen content, it could be inferred that pyrrolic nitrogen species are highly active pseudocapacitive sites for nitrogen-doped carbon materials. This work gives an ideal model for understanding the contribution of pyrrolic nitrogen species in N-doped carbon materials.
Parkinson’s disease (PD) is one of the most prevalent and life-threatening neurodegenerative disease and mainly characterized by lack of sufficient dopaminergic neurons in the substantia nigra pars ...compacta (SNc). Although current treatments help to alleviate clinical symptoms, effective therapies preventing neuronal loss remain scarce. Tovophyllin A (TA), one of the xanthones extracted from
Garcinia mangostana
L. (GM), has recently been reported to play a beneficial role in the therapy of neurodegenerative diseases. In our research, we explored whether TA has protective effects on dopaminergic neurons in PD models. We found that TA significantly reduced apoptotic cell death in primary cortical neurons treated with 1-methyl-4-phenyl pyridinium (MPP
+
) or paraquat (PQ) in the
in vitro
PD model. In an
in vivo
acute PD model induced by 1-methyl4-phenyl-1,2,3,5-tetrahydropyridine (MPTP) treatment, TA also attenuated the resulting behavioral dysfunctions and dopaminergic neuron loss. In the collected brain tissues, TA increased the phosphorylation of Akt and GSK-3β, which may be related to TA-mediated dopaminergic neuronal protective effects. In summary, our results illustrated that TA is a powerful cytoprotective agent for dopaminergic neurons in the MPTP-induced PD model, suggesting TA as a possible therapeutic candidate for PD.
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