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Heterostructured Pt/Mo2C (C) was synthesized via the integration of Pt and Mo species on Vulcan-C and it exhibited superior catalytic activity and stability for the HER, greatly enhancing the Pt catalytic capacity with a H2 amount of 6837.28 mmol h−1 g−1.

To examine the associations of serum concentrations of adiponectin and leptin and leptin/adiponectin ratio (LAR) in early pregnancy with risk of gestational diabetes mellitus (GDM) in Chinese women. The predictive ability of those biomarkers for GDM was also assessed.Within the Tongji-Shuangliu Birth Cohort, a nested case-control study was established with 332 GDM cases and 664 matched controls at 1:2 ratio on age (±3 years) and gestational age (±4 weeks). Serum adiponectin and leptin levels were measured in early pregnancy (median gestational week, 11; range, 6-15). Conditional logistic regression models with adjustment for potential covariates were used to evaluate the associations.Multivariable-adjusted odds ratios (ORs) comparing extreme quartiles of adiponectin, leptin and LAR were 0.55 (95 % CI, 0.35, 0.85), 1.96 (95 % CI, 1.19, 3.24), and 2.72 (95 % CI, 1.63, 4.54) for GDM, respectively (All P-trend 0.02). Adding adiponectin and leptin to a conventional prediction model (including traditional risk factors and fasting glucose) increased the C-statistics from 0.708 (95 % CI, 0.674, 0.741) to 0.728 (95 % CI, 0.695, 0.760), and achieved a net reclassification improvement of 0.292.Our findings indicate that adiponectin is inversely associated with GDM, while leptin and LAR are positively associated with GDM in Chinese pregnant women.

Based on the dual challenges of the global energy crisis and environmental pollution, hydrogen has been recognized as an ideal alternative internal combustion engine (ICE) fuel. To improve the combustion efficiency of hydrogen direct injection ICE, we numerically analyzed the effects of different injection parameters, including injection timing, injection pressure, and dual injection, on the formation of a hydrogen-air mixture using the CONVERGE software from the perspective of mass transfer and flow state. It was determined that it is enough to set the injection timing to −88° after top dead center (ATDC) for both uniform mixture and desirable indicated thermal efficiency (ITE). However, when the injection timing is set to −43° ATDC, an acceptable ITE and effective combustion can be achieved by employing the “jet-room coordination” effect of the ω chamber. Injection pressure has a minimal effect on mixture formation and combustion. In contrast, the timing and mass fraction of secondary injection have a significant influence on tumble strength, which is a key factor for the mixture improvement.

In this work, a one-pot solid phase reaction was used to synthesize PtIn/3D-GNs composites with different alloying degrees. The as-synthesized composites were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and X-ray photoelectron spectroscopy (XPS). The results indicate that PtIn alloy was formed in the PtIn/3D-GNs composites. However, In(0) content in the composites (denoted as PtIn/3D-GNs (O)) when In2O3 was used as a precursor of In is almost twice as much as that in the composites (denoted as PtIn/3D-GNs (S)) using In(NO3)3 as a precursor of In, which indicates the higher Pt–In alloying degree in PtIn/3D-GNs (O). Electrochemical tests show that PtIn/3D-GNs composites exhibit superior electrocatalytic activity, better stability and enhanced antipoisoning ability toward methanol oxidation reaction (MOR) in comparison with Pt/3D-GNs and the commercial Pt/C. Interestingly, the synergistic effect between the charge separation of In2O3 and the SPR excitation of In(0) under light irradiation contributes to their good electro-photocatalytic performance under simulated sunlight irradiation. Especially, the higher Pt–In alloying degree in PtIn/3D-GNs (O) contributes to its better conductivity, which is responsible for its more efficient electro-photocatalytic properties.

An aqueous solution synthesis method was used to synthesize a Pt-Ni/GNs composite containing trace amounts of Ni species by the aid of self-etching or acid-etching process. Its component structure and morphology were characterized by X-ray diffraction (XRD), Transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) and Raman spectra, etc. The obvious cracked Pt-Ni nanoclusters can be found in Pt-Ni (trace)/GNs which contains only trace Ni species. Electrochemical experiments indicate that Pt-Ni (trace)/GNs exhibits bi-functional electrocatalytic performance for MOR and ORR with the mass activity of 1009.98 mA mg−1 and 157.7 mA mg−1, respectively, which is superior to commercial Pt-Ru/C-JM. It is proven that the trace Ni species contribute to the enhanced electrocatalytic performance of the Pt-Ni/GNs composite.

A facile microwave assisted strategy was used to synthesize a series of Pt–Au/graphene (simplified as Pt–Au/GNs) catalysts with controllable Pt:Au ratios, in which K2PtCl4, HAuCl4 and graphite oxide were synchronously reduced using ethanol as a reducing agent. When a lower amount of Au is added, Pt and Au species form the heterostructure in Pt-Au/GNs composites, while as Au content increases further, excess Au particles are easy to agglomerate. Electrochemical experiments show that Pt–Au/GNs composites with lower Au content exhibit advantageous electrocatalytic performances and stability simultaneously towards methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR). What's interesting is that, under simulated sunlight irradiation, Pt-Au/GNs composites with higher Au content behave superior electro-photo catalytic activities towards MOR and ORR, which is proportional to the size and content of Au. Comprehensive consideration of catalytic performance and cost, Pt–Au/GNs with the optimal Pt: Au ratio of 1:0.1 can serve as an efficient bifunctional electro-photo catalyst for catalyzing MOR and ORR.