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The electrode Pt-loading has an effect on the number of active sites and the thickness of catalyst layer, which has huge influence on the mass transfer and water management during dynamic process in PEMFCs. In this study, membrane electrode assemblies with different Pt-loadings were prepared, and PEMFCs were assembled using those membrane electrode assemblies with traditional solid plate and water transport plate as cathode flow-field plates, respectively. The performance and electrochemical surface area of cells were characterized to evaluate the membrane electrode assemblies degradation after rapid current-variation cycles. Scanning electron microscope and transmission electron microscope were used to investigate the decay of catalyst layers and Pt/C catalyst. With the increase of Pt-loading, the performance degradation of membrane electrode assemblies will be mitigated. But higher Pt-loading means thicker catalyst layer, which leads to a longer pathway of mass transfer, and it may result in carbon material corrosion in membrane electrode assemblies. The decay of Pt/C catalyst in cathode is mainly caused by the corrosion of carbon support, and the degradation of anode Pt/C catalyst is a consequence of migration and aggregation of Pt particles. And using water transport plate is beneficial to alleviating the age of cathode Pt/C catalyst.

To accelerate the kinetics of the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells, ultrafine Pt nanoparticles modified with trace amounts of cobalt were fabricated and decorated on carbon black through a strategy involving modified glycol reduction and chemical etching. The obtained Pt36Co/C catalyst exhibits a much larger electrochemical surface area (ECSA) and an improved ORR electrocatalytic activity compared to commercial Pt/C. Moreover, an electrode prepared with Pt36Co/C was further evaluated under H2-air single cell test conditions, and exhibited a maximum specific power density of 10.27 W mgPt−1, which is 1.61 times higher than that of a conventional Pt/C electrode and also competitive with most state-of-the-art Pt-based architectures. In addition, the changes in ECSA, power density, and reacting resistance during the accelerated degradation process further demonstrate the enhanced durability of the Pt36Co/C electrode. The superior performance observed in this work can be attributed to the synergy between the ultrasmall size and homogeneous distribution of catalyst nanoparticles, bimetallic ligand and electronic effects, and the dissolution of unstable Co with the rearrangement of surface structure brought about by acid etching. Furthermore, the accessible raw materials and simplified operating procedures involved in the fabrication process would result in great cost-effectiveness for practical applications of PEMFCs.

Water management of proton exchange membrane fuel cells (PEMFCs) is of vital importance to achieve better performance and durability. In this study, porous hydrophilic water transport plates (WTPs) with different pore structures were prepared and employed to improve water management in PEMFCs. Polarization curves, electrochemical impedance spectroscopy (EIS) and water balance were tested to investigate the effect of pore structure on cell performance and water transport process. The results show that pore structure has little effect on drainage function due to excess liquid water flux of WTPs, while the membrane hydration is improved with increased surface evaporation rate of WTPs, resulting in better cell performance. The favorable cell performance shows that WTP is a promising technique to improve water management in PEMFCs.

Objective To investigate the effect of Qianggan capsules on liver fibrosis score and insulin resistance index in patients with nonalcoholic fatty liver disease (NAFLD). Methods A total of 85 NAFLD patients who were treated in the Eighth People′s Hospital of Shanghai from August 2014 to July 2015 were enrolled and randomly divided into treatment group (45 patients) and control group (40 patients). The patients in the treatment group were given Qianggan capsules, and those in the control group were given polyene phosphatidylcholine capsules. The course of treatment was 24 weeks for both groups. The changes in serum aminotransferases ［aspartate aminotransferase (AST) and alanine aminotransferase (ALT)］, homeostasis model assessment of insulin resistance (HOMA-IR), and NAFLD fibrosis score (NAFLDFS) after treatment were observed in both groups. The t-test was used for comparison of continuous data between groups, before-after comparison within each group was made by paired t-test; and the chi-square test was used for comparison of categorical data between groups. Results Both groups showed significant improvements in ALT and AST levels after treatment (all P＜0.01). After treatment the treatment group showed significant reductions in HOMA-IR and NAFLDFS (3.58±0.85 vs 2.48±078，t=6.40，P＜0.01; -1.78±1.24 vs -2.35±0.98,t=2.40,P＜0.01) and the treatment group had significantly lower HOMA-IR and NAFLDFS than the control group(12.48±0.78 vs 3.09±0.89, t=3.36, P＜0.01; -2.35±0.98 vs -1.48±1.08, t=3.80, P＜0.01). No serious adverse events were observed during the course of treatment. Conclusion Qianggan capsules not only reduce the levels of serum aminotransferases, but also improve insulin resistance and reduce fibrosis degree in NAFLD patients.

An appropriate water balance between membrane dehydration and water flooding is essential to improve the performance and endurance of the polymer electrolyte membrane fuel cell (PEMFC). In this study, a novel hydrophilic porous carbon plate (HPCP) is employed as a water transport plate (WTP) to achieve the water balance by virtue of its humidification and water drainage functions. The HPCP is fabricated by electrochemically assisted self-assembly of a hydrophilic silica film on the pore surface of a porous carbon plate (PCP). To overcome the problem that the precursor is unable to enter the hydrophobic pores of the PCP, a novel electro-deposition device forcing the precursor to flow through the pores is designed. Consequently, continuous hydrophilic pores are obtained which promotes the ability of humidification and water drainage. Owing to the humidification function of the HPCP, at the current density of 1000 mA cm −2 , the voltage of the cell with HPCP is 270 mV higher than that with solid plate (SP) under no-humidity. Attributed to the water drainage function, the runtime of the cell is twelve times longer than that with SP under dead-ended cathode operation.

Allelopathic inhibition activities of four submerged macrophytes (Potamogeton maackianus, Vallisneria spiralis, Elodea nuttalli Ceratophyllum demersum) on Microcystis aeruginosa are investigated by a series of experiments in a short-term bioassay. Individual algal test reveals culture solution of P. maackianus and C. demersum have better effects on algal growth inhibition. Furthermore, continuous addition assays show strong growth inhibition by culture solution. Inhibitory activity is different in aquatic extracts from different section of P. maackianus. Removing the disturbance of microorganism by autoclaving influences algal assay. These results provide that unstable and excreting continuously allelopathic compounds by submerged macrophytes are the primary cause of algal growth inhibition. Interference with algal growth experiments was investigated in microorganism and nutrient elements of nitrogen and phosphorus.