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Background and aims Renal dysfunction is a potent risk factor for cardiovascular diseases, including stroke. This study aimed to evaluate the impact of admission estimated glomerular filtration rate (eGFR) levels on short-term (1-month) and long-term (1-year) mortality in patients with acute ischemic stroke. Methods From the Taiwan Stroke Registry data, we classified ischemic stroke patients, identified from April 2006 to December 2015, into 5 groups by eGFR at admission: ≥ 90, 60–89, 30–59, 15–29, and Results Among 52,732 ischemic stroke patients, 1480 died within one month. The 1-month mortality rate was over 5-fold greater in patients with eGFR Conclusions After acute ischemic stroke, patients with reduced eGFR are at elevated risks of short-term and long-term deaths in a graded relationship.

We investigated the impact of serum cholesterol levels on 30-day mortality after ischemic stroke in dialysis patients.From the Taiwan Stroke Registry data, we identified 46,770 ischemic stroke cases, including 1101 dialysis patients and 45,669 nondialysis patients from 2006 to 2013.Overall, the 30-day mortality was 1.46-fold greater in the dialysis group than in the nondialysis group (1.75 versus 1.20 per 1000 person-days). The mortality rates were 1.64, .62, 2.82, and 2.23 per 1000 person-days in dialysis patients with serum total cholesterol levels of 120 mg/dL, 120-159 mg/dL, 160-199 mg/dL, and ≥200 mg/dL, respectively. Compared to dialysis patients with serum total cholesterol levels of 120-159 mg/dL, the corresponding adjusted hazard ratios of mortality were 4.20 (95% confidence interval [CI] = 1.01-17.4), 8.06 (95% CI = 2.02-32.2), and 6.89 (95% CI = 1.59-29.8) for those with cholesterol levels of 120 mg/dL, 160-199 mg/dL, and ≥200 mg/dL, respectively.Dialysis patients with serum total cholesterol levels of ≥160 mg/dL or 120 mg/dL on admission are at an elevated hazard of 30-day mortality after ischemic stroke.

Yttria-stabilized zirconia (YSZ) is the most commonly used electrolyte material for solid oxide fuel cells. The use of relatively inexpensive metal components would require a trade-off in the lowering of the operating temperature below 800 °C. However, the reduced temperature results in an increased resistivity of YSZ. This can be overcome by reducing the electrolyte thickness using thin film techniques. In this study, the preparation of a thin film of YSZ via the sputter deposition technique was reported. YSZ electrolyte films were deposited on anode substrates at 650/750 °C. The gas permeability test indicated a gas-tight electrolyte with a gas leak rate − 7 lcm − 2 s − 1 . The measured open circuit voltage was 1.1 V, while the maximum power density was 515 mW cm − 2 .

Dense electrolyte films ∼15 μm thick made of samarium-doped ceria (SDC) are fabricated by spin-coating. The SDC powders are synthesized by the glycine nitrate combustion process. It is found that nanoscale SDC powders can be obtained at 1000 °C. Cells constructed with an SDC electrolyte, a NiO + SDC composite anode, and an SSC–SDC/SSC bi-layer cathode are fabricated and tested at temperatures from 400 to 650 °C. SEM micrographs show that the SDC electrolyte layer adheres well to the porous anode and the cathode. The maximum power densities of the cell are 38, 84, 185, 303, 438, and 549 mW cm −2 at 400, 450, 500, 550, 600, and 650 °C, respectively. Analysis of the impedance spectra indicates that the electrode polarization dominates the total cell resistance at temperatures below 550 °C, and the ohmic resistance dominates the total cell resistance above 550 °C. The activation energies of the resistances show that the cell performance is significantly controlled by the electrode polarization resistance. Durability tests are performed over 950 h and indicate that the power density and the voltage gradually degrade with time at a rate of ∼0.03 mW cm −2 h −1 and ∼0.07 mV h −1 , respectively. Hence, a low-temperature solid oxide fuel cell has been developed.

The various composite cathode layers on the solid oxide fuel cells (SOFCs) with a dense electrolyte of yttria-stabilized zirconia (YSZ) are investigated in this study. The ceramic powders of La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF), Ba0.5Sr0.5Co0.2Fe0.8O3−δ (BSCF), La0.9Sr0.1Ga0.8Mg0.2O3−δ (LSGM), and Gd0.2Ce0.8O3−δ (GDC) are prepared by the glycine-nitrate combustion process. The different formations of composite cathode layers are coated onto the NiO–YSZ/YSZ half-cells via a screen printing method. Scanning electron microscopy (SEM) micrographs show that all of the samples can be well adherent to the YSZ electrolyte. From the energy dispersive X-ray (EDX) result, the undesired compound of SrZrO3 is formed between the YSZ electrolyte and the composite cathode layers with LSCF and BSCF at the sintering temperature of 1000 °C. According to the results of the electrochemical test and electrochemical impedance spectroscopy (EIS), the composite cathode layer with YSZ–La0.8Sr0.2MnO3−δ (LSM) interlayer exhibits the best electrochemical performance. The maximum power density can achieve the value above 400 mW/cm2 for the samples with YSZ–LSM interlayer.

The Sm 0.5 Sr 0.5 CoO 3− δ (SSC) with perovskite structure is synthesized by the glycine nitrate process (GNP). The phase evolution of SSC powder with different calcination temperatures is investigated by X-ray diffraction and thermogravimetric analyses. The XRD results show that the single perovskite phase of the SSC is completely formed above 1100 °C. The anode-supported single cell is constructed with a porous Ni–yttria-stabilized zirconia (YSZ) anode substrate, an airtight YSZ electrolyte, a Sm 0.2 Ce 0.8 O 2− δ (SDC) barrier layer, and a screen-printed SSC–SDC composite cathode. The SEM results show that the dense YSZ electrolyte layer exhibits the good interfacial contact with both the Ni–YSZ and the SDC barrier layer. The porous SSC–SDC cathode shows an excellent adhesion with the SDC barrier layer. For the performance test, the maximum power densities are 464, 351 and 243 mW cm −2 at 800, 750 and 700 °C, respectively. According to the results of the electrochemical impedance spectroscopy (EIS), the charge-transfer resistances of the electrodes are 0.49 and 1.24 Ω cm 2 , and the non charge-transfer resistances are 0.48 and 0.51 Ω cm 2 at 800 and 700 °C, respectively. The cathode material of SSC is compatible with the YSZ electrolyte via a delicate scheme employed in the fabrication process of unit cell.

The anode-supported single cell was constructed with porous Ni–Yittria-stabilized zirconia (YSZ) as the anode substrate, an airtight YSZ as the electrolyte, and a screen-printed La 0.8 Sr 0.2 MnO 3−δ (LSM)–Gadolinia-doped ceria (GDC)/LSM double-layer cathode. The SEM results show that the YSZ thin film is highly integrated, fully dense with a thickness of 13 μm, and exhibits excellent compatibility between cathode and electrolyte layers. The effects of feed rates of the reactants, temperature, and contact pressure between the current collector and the unit cell were systematically investigated. The results are based on the assumption that the anode contribution to the polarization resistance is negligible. Our analysis showed that the electrochemical reaction is limited by mass transfer control when the airflow rate is decreased to 500 ml min −1 . The maximum power density is 204.6 mW cm −2 at 800 °C with H 2 and air at flow rates of 800 and 2000 ml min −1 , respectively. According to the AC-impedance data, the resistances of charge transfer at the electrode/electrolyte interface are 3.79 and 1.90 Ω cm 2 . The resistances of oxygen-reduction processes are 3.63 and 1.01 Ω cm 2 at 700 and 800 °C, respectively. The results from the sensitivity analysis of the variation of contact pressure between current collectors and membrane electrode assembly (MEA) show that the influence is enhanced at the regions of the high current density.

Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3− δ (BSCF) and gadolinia-doped ceria (GDC) were synthesized via a glycine-nitrate process (GNP). A cubic perovskite of BSCF was observed by X-ray diffraction (XRD) at a calcination temperature above 950 °C. An anode-supported solid-oxide fuel cell was constructed from the porous NiO + YSZ as the anode substrate, the yittria-stabilized zirconia (YSZ) as the electrolyte, and the porous BSCF-GDC layer as the cathode with a GDC barrier layer. For the performance test, the maximum power density was 191.3 mW cm −2 at a temperature of 750 °C with H 2 fuel and air at flow rates of 335 and 670 sccm, respectively. According to the AC-impedance data, the charge-transfer resistances of the electrodes were 0.10 and 1.59 Ω cm 2 , and the oxygen-reduction and oxygen-ion diffusion resistances were 0.69 and 0.98 Ω cm 2 at 750 and 600 °C, respectively. SEM microstructural characterization indicated that the fuel cell as fabricated exhibited good compatibility between cathode and electrolyte layers.

A novel heterogeneous magnetic nanocatalyst was designed by conjugating copper(II) ions with chitosan-bound magnetic nanocarrier. Its hydrolytic activity for phosphodiesters was evaluated by investigating the hydrolysis of secondary ester bis-(nitrophenyl) phosphate (BNPP) in aqueous media. The maximum hydrolysis rate of BNPP was observed around the p K a of nanocatalyst which was found to be 12. The kinetic studies revealed that the binding affinity of BNPP to the copper(II)-chelated chitosan magnetic nanocarrier was low as compared to other catalyst systems. However, the rate constants ( k cat ) and maximum reaction rate ( V max ) were found to be higher with lower activation energy for the developed nanocatalyst. Moreover, the developed nanocatalyst was magnetically recoverable and also had good reusability.

The magnetic chitosan nanoparticles of 13.5 nm were prepared as a magnetic nano-adsorbent by the carboxymethylation of chitosan and the followed binding on the surface of Fe 3 O 4 nanoparticles via carbodiimide activation. Their saturation magnetization, remanent magnetization, coercivity, and squareness were 62 emu/g, 1.8 emu/g, 6.0 Oe, and 0.029, respectively, reflecting their superparamagnetic property. The binding reaction of carboxymethyl chitosan on the surface of Fe 3 O 4 nanoparticles was much faster than the self-crosslinking of carboxymethyl chitosan, and the appropriate reaction time was 1 h. At low carboxymethyl chitosan concentrations, the binding efficiency could be as high as 100%. The maximum amount of chitosan bound on the Fe 3 O 4 nanoparticles was 4.92 wt%. In addition, magnetic chitosan nano-adsorbent was shown to be quite efficient for the fast removal of Co(II) ions at pH 3–7 and 20–45 °C. The maximum adsorption capacity for Co(II) ions occurred at pH 5.5, and the adsorption process was exothermic in nature with an enthalpy change of −12.04 kJ/mol. The equilibrium was achieved within 1 min, and the adsorption data obeyed the Langmuir equation with a maximum adsorption capacity of 27.5 mg/g (557 mg/g based on the weight of chitosan) and a Langmuir adsorption equilibrium constant of 0.034 l/mg at 25 °C. Such fast adsorption rate and high adsorption capacity could be attributed to the absence of internal diffusion resistance and the high specific surface area.