Hydrogenated Boride-Assisted Gram-Scale Production of Platinum-Palladium Alloy Nanoparticles on Carbon Black for PEMFC Cathodes: A Study from a Practical Standpoint.

Platinum-palladium (PtPd) alloy catalysts with high durability are viable substituents to commercial Pt/C for proton exchange membrane fuel cells (PEMFCs). Herein, a facile approach for gram-scale preparation of PtxPd100-x alloy nanoparticles on carbon black is developed. The optimized Pt54Pd46/B-C catalyst shows a mass activity (MA) of 0.549 A mgPt-1 and a specific activity (SA) of 0.463 mA cm-2 at the rotating disk electrode (RDE) level, which are 3.4 and 1.9 times those of commercial Pt/C, respectively. In H2/O2 and H2/air PEMFCs, the membrane electrode assembly (MEA) with Pt54Pd46/B-C achieves peak power densities of 2.33 and 1.04 W cm-2, respectively, and shows negligible performance degradation after 100 h of running in H2/O2 conditions. Moreover, the MA of MEA with Pt54Pd46/B-C in H2/O2 PEMFC reaches 0.978 A mgPt+Pd-1 beyond the 2020 target of the Department of Energy (DOE) of 0.44 A mgPt-1. After 30k cyclic voltammetry cycles in PEMFC, the MA loss and cell voltage loss of MEA with Pt54Pd46/B-C are well within the DOE 2020 target. Density functional theory calculations reveal that the PtPd(111) surface can weaken the adsorption of *OOH and *OH compared to the Pt(111) surface, indicating that Pt54Pd46/B-C is more energetically favorable for the oxygen reduction reaction (ORR) than commercial Pt/C. This study offers a new approach for batch preparation of PtPd alloy-based catalysts for PEMFCs.

Fe2O3/NiO Interface for the Electrochemical Oxygen Evolution in Seawater and Domestic Sewage.

Hydrogen production from the electrolysis of seawater and domestic sewage is more attractive than that from pure water, especially in regions where freshwater resources are scarce. However, under such harsh conditions, higher requirements are put forward for the catalytic activity and adaptability of a catalytic electrode. Herein, we advance an ultrasimple dipping-and-heating method to engineer the surface of Ni foam (NF) into an interface-rich FeNi oxide layer and realize an exceptional oxygen evolution reaction (OER) performance. It only requires overpotentials of 182 and 267 mV to achieve current densities of 10 and 1000 mA cm-2 in 1 M KOH, respectively, which are significantly lower than those of the recently reported catalysts. The as-prepared FNE300||MoNi4/MoO2 electrolyzer realizes the industrial demand of 500 mA cm-2 at low voltages of ∼1.75 V for overall alkaline natural seawater and domestic sewage electrolysis, as well as satisfactory stability. Density functional theory (DFT) calculations indicate that modifying the electronic structure so as to optimize the intermediate adsorption is well achieved by constructing the interfaces between NiO and Fe2O3. The interaction of Fe with oxygen intermediates can be optimized by e--e- repulsion between Ni2+ and oxygen intermediates. This work provides a facile approach to fabricate an electrocatalyst for seawater and domestic sewage electrolysis, which is of great significance to the synergetic development of hydrogen economy and environmental science.

Up-regulation of circ-SMAD7 inhibits tumor proliferation and migration in esophageal squamous cell carcinoma.

BACKGROUND: Increasing evidences demonstrate that circular RNAs (circRNAs) play an important role in the development and progression of human cancers. Nevertheless, the functions and molecular mechanism of circRNAs in esophageal squamous cell carcinoma (ESCC) tumorigenesis are largely unknown. The purpose of this research is to investigate the expression and potential role of a new circular RNA named circ-SMAD7 on ESCC carcinogenesis. MATERIALS AND METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure circ-SMAD7 expression amount in both ESCC plasmas and tissues. Then the correlation between the expression of circ-SMAD7 and clinicopathological features was analyzed. Furthermore, by loss-of-function and gain-of-function experiments in ESCC cells, a functional analysis of circ-SMAD7 on ESCC cell proliferation and migration was performed. RESULTS: The expression of circ-SMAD7 was validated to be significantly down-regulated in ESCC plasmas in comparison with normal controls, showing a high negative correlation with TNM stage (P = 0.000) and lymphatic metastasis (P = 0.000). Moreover, circ-SMAD7 was significantly down-regulated in ESCC tissues compared to adjacent normal tissues. Furthermore, Loss-of-function and gain-of-function experiments revealed that the expression level of circ-SMAD7 affected the proliferation and migration of ESCC cell lines. CONCLUSION: Our study firstly exposed that over-expressioncirc-SMAD7, an influential regulator in cancer progression, can inhibit tumor proliferation and migration in ESCC and have the potential of becoming a biomarker for the diagnosis and therapy of ESCC.

Circ-DLG1 promotes the proliferation of esophageal squamous cell carcinoma.

BACKGROUND: Circular RNAs (circRNAs) are a class of noncoding RNAs with closed loop structures. There has been growing evidence showing that circRNAs are involved in the pathogenesis of human diseases including various carcinomas. Our study is aimed to investigate the association between a new circRNA named circ-DLG1 (hsa_circ_0007203) and esophageal squamous cell carcinoma (ESCC) carcinogenesis. METHODS: The circ-DLG1 expression levels were detected by real-time quantitative reverse transcription-polymerase chain reaction in cells, tissues, and plasmas. The correlation between circ-DLG1 expression and clinicopathologic features was then analyzed. The effect of circ-DLG1 expression on cell proliferation was evaluated in vitro by CCK8 assay and clone formation experiment. Finally, a network of circ-DLG1 with its targeted miRNA interactions and corresponding mRNAs was constructed. RESULTS: circ-DLG1was found to be significantly upregulated in ESCC cells, tissues, and plasmas compared to normal cases. Furthermore, in vitro assays, TE10 and KYSE180, of the ESCC cell lines demonstrated that knockdown of circ-DLG1 reduced cell proliferation significantly. Prediction and annotation revealed that circ-DLG1 was able to sponge to 20 miRNAs and 60 corresponding target mRNAs. CONCLUSION: Our study indicated that upregulation of circ-DLG1 promoted esophageal cell proliferation ability and might serve as a novel biomarker for ESCC.