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The liquid and gas diffusion layer is a key component of proton exchange membrane water electrolyzer (PEMWE), and its interfacial contact resistance (ICR) and corrosion resistance have a great impact on the performance and durability of PEMWE. In this work, a novel hybrid coating with Au contacts discontinuously embedded in a titanium oxidized layer was constructed on a Ti felt via facile electrochemical metallizing and followed by a pre-oxidization process. The physicochemical characterizations, such as scanning electron microscopy, energy dispersive spectrometer, and X-ray diffraction results confirmed that the distribution and morphology of the Au contacts could be regulated with the electrical pulse time, and a hybrid coating (Au-TiO2/Ti) was eventually achieved after the long-term stability test under anode environment. At the compaction force of 140 N cm−2, the ICR was reduced from 19.7 mΩ cm2 of the P-Ti to 4.2 mΩ cm2 of the Au-TiO2/Ti. The corrosion current density at 1.8 V (RHE) is 0.689 μA cm−2. Both the ICR and corrosion resistance results showed that the prepared protective coating could provide comparable ICR and corrosion resistance to a dense Au coating. [ABSTRACT FROM AUTHOR]

Over the years, graphene oxide (GO) with unique permeability and selectivity has been extensively researched for hydrophilic enhancement modification, especially as the separation layer of oil–water separation composite membranes. However, the poor stability caused by hydration of GO, and the low water flux caused by the lamellar compaction limit its application. In this study, a surface modification strategy based on metal polyphenol coordination was proposed to address these problems by co-deposition of tannic acid-graphene oxide (TA-GO) and TiO2 on electrospun polyvinylidene fluoride (PVDF) membrane. TiO2 was inserted into GO layers to expand the interlayer spacing and prevent membrane compaction. Moreover, the interlayer force was enhanced by TA and Fe3+ through covalent bonds, cation-π, and coordination bond. The results demonstrated that the underwater oil contact angle of resultant composite membrane reached 152.5°. In addition, it has a high flux (243.11 L/h·m2·bar) and oil (> 98%)/salt (> 47%) rejection, which can be maintained even after ultrasonic treatment for 30 min. This work proposed a practical and environmental approach to construct a steady GO-modified hydrophilic membrane. [ABSTRACT FROM AUTHOR]

Ascites syndrome (AS) in chickens is associated with profound vascular remodelling and increased pulmonary artery pressure as well as right ventricular hypertrophy. Classical transient receptor potential cation channels (TRPCs) are key regulators of cardiac hypertrophy that act via regulation of calcium influx in mammals. We investigated whether classical transient receptor potential channels in chickens with right ventricular hypertrophy still possess this mechanism for regulating Ca2+ flux. Intravenous injection of cellulose particles was successfully used to induce AS in chickens, and tissues were examined 22 days after treatment. The chickens in the test group showed cardiac hypertrophy with oedema of the cardiac muscle and disruption of myofilaments. The right-to-total ventricle weight ratio (RV/TV), the levels of serum aspartate aminotransferase (AST) and creatine kinase (CK) of the test group were significantly higher than in the control group. Intracellular calcium levels were significantly increased in cardiomyocytes from chickens in the test group. Gene expression of TRPC3, TRPC4, TRPC5, TRPC6 and TRPC7 in heart tissues from the test group showed no significant differences compared with controls. However, TRPC1 protein levels, as well as mRNA levels, were down-regulated in the heart muscle of AS chickens (P < 0.05). Although we observed an increase in calcium concentration, the expression of TRPC1 decreased in cardiac cells. We hypothesized that an increase in intracellular free calcium concentration could inversely regulate calcium channel expression. RESEARCH HIGHLIGHTS Intracellular Ca2+ levels were increased in the myocardium of AS broilers. Expression of TRPC1, which mediates calcium influx, was decreased in the myocardium of AS broilers. The relationship between intracellular Ca2+ levels and expression of TRPC1 requires further study. [ABSTRACT FROM AUTHOR]

Candida lipolytica with efficient decolorization of Acid Red 3 G was screened. An experimental design based on the response surface method was applied to finding the optimal conditions. The results showed that the optimum dye decolorizing conditions were 160 r/min with shake cultivation, initial dye concentration (400 mg/ L) , incubation temperature 30 °C with inoculum amount 5 % , and the medium compositions were glucose 21 g/L, yeast extract 10 g/L, Mg2+ 20 mmol/L, and Cu2+ 9. 5 mg/L. The Candida lipolytica culture exhibited decolorization 97. 5 % within 48 h. These results demonstrated that the Candida lipolytica culture had high potential to decolorize azo dyes textile-dyeing wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly-dispersed Ir clusters supported on IrO 2 (Ir-IrO 2) are prepared. • Heterogeneous interfaces and oxygen vacancies-rich surfaces are developed. • Ir-IrO 2 demonstrates improved catalytic activity and electrochemical durability for the OER. • The improvement originates from the synergistic effects of heterogeneous interfaces and oxygen vacancies-rich surfaces. The development of efficient and stable catalysts for oxygen evolution reaction (OER) has recently attracted much attention, and the major challenge of current research is to offer fast kinetics and enhance the durability in a harsh oxidising environment. Herein, an effective strategy is developed to construct a unique heterogeneous interface between Ir nanoclusters and IrO 2 via a facile and scalable chemical reduction method, followed by the thermal treatment under Ar atmosphere. Both the transmission electron microscope and X-ray photoelectron spectroscopy results revealed that the as-prepared Ir-IrO 2 has been engineered with heterogeneous interfaces and oxygen vacancies-rich surfaces. Benefited from newly-formed active surfaces and the oxygen vacancies-rich surfaces, the Ir-IrO 2 catalyst exhibits increased catalytic active sites and enhanced catalytic activity towards the OER compared with the pure IrO 2 and commercial IrO 2. The over-potential of the Ir-IrO 2 is ca. 329 mV at 10 mA cm−2, and the mass activity is ca. 1851 A g IrO2 −1 at 1.60 V (vs. RHE), about 2.4 times that of the commercial IrO 2 (ca. 779 A g IrO2 −1). In addition, both the improved catalytic performance and durability for the OER is further confirmed in PEM water electrolysis cell. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) are the most promising clean energy source in the 21st century. In order to achieve a high power density, electrocatalytic performance, and electrochemical stability, an ordered array structure membrane electrode is highly desired. In this paper, a new porous Pt-TiO2@C ordered integrated electrode was prepared and applied to the cathode of a PEMFC. The utilization of the TiO2@C support can significantly decrease the loss of catalyst caused by the oxidation of the carbon from the conventional carbon layer due to the strong interaction of TiO2 and C. Furthermore, the thin carbon layer coated on TiO2 provides the rich active sites for the Pt growth, and the ordered support and catalyst structure reduces the mass transport resistance and improves the stability of the electrode. Due to its unique structural characteristics, the ordered porous Pt-TiO2@C array structure shows an excellent catalytic activity and improved Pt utilization. In addition, the as-developed porous ordered structure exhibits superior stability after 3000 cycles of accelerated durability test, which reveals an electrochemical surface area decay of less than 30%, considerably lower than that (i.e., 80%) observed for the commercial Pt/C. [ABSTRACT FROM AUTHOR]

• A diffusion model for structural dynamic response reconstruction is proposed. • A conditional input is introduced for the model to achieve supervised learning. • Data fusion enhances reconstruction accuracy by providing extra frequency features. • The model effectiveness is validated by modal identification and robustness analysis. In structural health monitoring (SHM) systems, data loss inevitably occurs and reduces the applicability of SHM techniques, such as condition assessment and damage identification. The current mainstream data-driven method, generative adversarial networks (GAN), suffers from convergence difficulty, limiting the accuracy and efficiency of response reconstruction. In this study, a conditional diffusion model with data fusion (DF-CDM) is proposed for structural dynamic response reconstruction. The original unsupervised diffusion model is improved by introducing the conditional input and modifying the deep denoising neural network to achieve supervised learning. Besides, data fusion is developed to further utilize the frequency-domain information and improve the reconstruction quality of the time-domain signals. The proposed model is validated on a three-span continuous bridge. Results show that the diffusion model with data fusion achieves the highest accuracy on the test set with R 2, RMSE and MAE equaling 0.821, 0.0053 and 0.0042 respectively. Compared with the state-of-the-art GAN model, the diffusion model without the adversarial modules has a more stable training process and better reconstruction performance in both time and frequency domains. The modal identification and robustness analysis further verify the effectiveness of the proposed model. The proposed diffusion model with data fusion achieves high-quality structural response reconstruction, guaranteeing the applicability and reliability of subsequent response-based structural analysis. [ABSTRACT FROM AUTHOR]