焦耳热快速合成双功能电催化剂用于高效水分解

电解水是有效的产氢方式之一,开发具有高催化活性的电极材料是当前电解水的研究热点,但仍面临诸多挑战。本研究报告了一种通过焦耳热技术快速制备多金属异质结构,并将其用作电解水的双功能电催化剂,展现出优异的电解水催化活性。通过焦耳热处理三种金属前驱涂覆的碳布,MoC和CoO/FeO异质结构形成。当其用作析氢(HER)和析氧(OER)的双功能催化剂时,仅需121 mV和268 mV的过电位,可以实现10 m A·cm^(-2)的电流密度。当用于两电极电解水时,MoC/FeO/CoO/CC作为阳极和阴极催化剂表现出优异的电催化性能和长期稳定性,仅需1.69 V即可实现10 mA·cm^(-2)的电流密度,并且展现出25小时的稳定性。本研究通过简单、快速的焦耳热技术实现了双金属/多金属异质结构的构筑,并应用于高效水电解,为合理设计多金属异质结构提供指导。

A distributed Grid-Xinanjiang model with integration of subgrid variability of soil storage capacity

Realistic hydrological response is sensitive to the spatial variability of landscape properties. For a grid-based distributed rainfall-runoff model with a hypothesis of a uniform grid, the high-frequency information within a grid cell will be gradually lost as the resolution of the digital elevation model(DEM) grows coarser. Therefore, the performance of a hydrological model is usually scale-dependent. This study used the GridXinanjiang(GXAJ) model as an example to investigate the effects of subgrid variability on hydrological response at different scales. With the aim of producing a more reasonable hydrological response and spatial description of the landscape properties, a new distributed rainfall-runoff model integrating the subgrid variability(the GXAJSV model) was developed. In this model, the topographic index is used as an auxiliary variable correlated with the soil storage capacity. The incomplete beta distribution is suggested for simulating the probability distribution of the soil storage capacity within the raster grid. The Yaogu Basin in China was selected for model calibration and validation at different spatial scales.Results demonstrated that the proposed model can effectively eliminate the scale dependence of the GXAJ model and produce a more reasonable hydrological response.

Unraveling the macroevolution of horseshoe bats(Chiroptera: Rhinolophidae: Rhinolophus)

Unraveling the diversification mechanisms of organisms is a fundamental and important macroevolutionary question regarding the diversity,ecological niche, and morphological divergence of life. However, many studies have only explored diversification mechanisms via isolated factors. Here,based on comparative phylogenetic analysis, we performed a macroevolutionary examination of horseshoe bats(Chiroptera: Rhinolophidae:Rhinolophus), to reveal the inter-relationships among diversification, intrinsic/extrinsic factors, and climatic ecological niche characteristics. Results showed a general slowing trajectory during diversification, with two dispersal events from Asia into Southeast Asia and Africa playing key roles in shaping regional heterogeneous diversity. Morphospace expansions of the investigated traits(e.g., body size,echolocation, and climate niche) revealed a decoupled pattern between diversification trajectory and trait divergence, suggesting that other factors(e.g., biotic interactions) potentially played a key role in recent diversification. Based on ancestral traits and pathway analyses, most Rhinolophus lineages belonging to the same region overlapped with each other geographically and were positively associated with the diversification rate, implying a competitive prelude to speciation. Overall, our study showed that multiple approaches need to be integrated to address diversification history. Rather than a single factor, the joint effects of multiple factors(biogeography, environmental drivers, and competition) are responsible for the current diversity patterns in horseshoe bats, and a corresponding multifaceted strategy is recommended to study these patterns in the future.

In situ embedded bismuth nanoparticles among highly porous carbon fibers for efficient carbon dioxide reduction

Electrocatalysis provides an optimal approach for the conversion of carbon dioxide(CO_(2))into high-value chemicals,thereby presenting a promising avenue toward achieve carbon neutrality.However,addressing the selectivity and stability challenges of metal catalysts in electrolytic reduction remains a daunting task.In this study,the electrospinning method is employed to fabricate porous carbon nanofibers loaded with bismuth nanoparticles with the help of in situ pyrolysis.The porous carbon nanofibers as conductive support would facilitate the dispersion of bismuth active sites while inhibiting their aggregation and promoting the mass transfer,thus enhancing their electrocatalytic activity and stability.Additionally,nitrogen doping induces electron delocalization in bismuth atoms through metal-support interactions,thus enabling efficient adsorption of intermediates for improving selectivity based on the theoretical calculation.Consequently,Bi@PCNF-500 exhibits the exceptional selectivity and stability across a wide range of potential windows.Notably,its faradaic efficiency(FE)of formate reaches 92.7%in H-cell and94.9%in flow cell,respectively,with good electrocatalytic stability.The in situ characterization and theoretical calculations elucidate the plausible reaction mechanism to obtain basic rules for designing efficient electrocatalyst.

XELOX doublet regimen versus EOX triplet regimen as first-line treatment for advanced gastric cancer:An open-labeled,multicenter,randomized,prospective phase III trial(EXELOX)

Background:There is no consensus on whether triplet regimen is better than doublet regimen in the first-line treatment of advanced gastric cancer(AGC).We aimed to compare the efficacy and safety of oxaliplatin plus capecitabine(XELOX)and epirubicin,oxaliplatin,plus capecitabine(EOX)regimens in treating AGC.Methods:This phase III trial enrolled previously untreated patients with AGC whowere randomly assigned to receive the XELOXor EOXregimen.The primary endpoint was non-inferiority in progression-free survival(PFS)for XELOX as compared with EOX on an intention-to-treat basis.Results:Between April 10,2015 andAugust 20,2020,448AGCpatientswere randomized to receive XELOX(n=222)or EOX(n=226).The median PFS(mPFS)was 5.0 months(95%confidence interval[CI]=4.5-6.0 months)in the XELOX arm and 5.5 months(95%CI=5.0-6.0 months)in the EOX arm(hazard ratio[HR]=0.989,95%CI=0.812-1.203;P_(non-inferiority)=0.003).There was no significant difference inmedian overall survival(mOS)(12.0 vs.12.0months,P=0.384)or objective response rate(37.4%vs.45.1%,P=0.291)between the two groups.In patients with poorly differentiated adenocarcinoma and liver metastasis,the EOX arm had a significantly longer mOS(P=0.021)and a trend of longer mPFS(P=0.073)than the XELOX arm.The rate of grade 3/4 adverse events(AEs)was 42.2%(90/213)in the XELOX arm and 72.5%(156/215)in the EOX arm(P=0.001).The global health-related quality of life(QoL)score was significantly higher in the XELOX arm than in the EOX arm during chemotherapy.Conclusions:This non-inferiority trial demonstrated that the doublet regimen was as effective as the triplet regimen and had a better safety profile and QoL as a first-line treatment for AGC patients.However,the triplet regimen might have a survival advantage in patients with poorly differentiated adenocarcinoma and liver metastasis.