A public survey was conducted in March 2015 in Japan asking public awareness, knowledge, perception and acceptance regarding hydrogen, hydrogen infrastructure and fuel cell vehicle. Changes in ...answers were found by comparing results of current survey to those of the two previous surveys that were conducted six and seven years ago. We found a large increase in the awareness and relatively a small improvement on knowledge on hydrogen energy, hydrogen infrastructure and fuel cell vehicle from the previous surveys. In contrast we did not find much changes in perception of risk and benefit on hydrogen society and hydrogen station and public acceptance of hydrogen infrastructure. Through the regression analyses we found the small influence of time background as well as the influence of risk and benefit perception of hydrogen infrastructure on the acceptance. In conclusion, we find people have become a little more positive about hydrogen infrastructure in the baseline but more cautious about the risk and benefits. This can be interpreted as a change in the quality of perception and acceptance, that is, the favorable prejudice to hydrogen energy and fuel cell technologies has changed towards a slightly more rational support.
•Public awareness, knowledge, perception and acceptance regarding hydrogen, hydrogen infrastructure and fuel cell vehicle.•Changes in awareness, knowledge, perception and acceptance at two time points.•Influence of time background (rollout of commercial fuel cell vehicle) on acceptance.•Quality of perception and acceptance.
Polymer electrolyte membrane fuel cells are an efficient and clean alternative power source, but high cost impedes widespread commercialization. The fuel cell membrane, e.g., Nafion, contributes ...significantly to this cost, and therefore, novel alternatives are required. Temperature is also an important factor; high temperature operation leads to faster reaction kinetics, lower electrocatalyst loading, and improved water management, thereby further reducing cost. However, higher temperature puts greater demands on the membrane. Conductivity is related strongly to humidification, and therefore, this generally decreases above 100 °C. Nanocellulose membranes for fuel cells in which the proton conductivity increases up to 120 °C are reported here for the first time. The hydrogen barrier properties are far superior to conventional ionomer membranes. Fuel cells with nanocellulose membranes are successfully operated at 80 °C. Additionally, these membranes are environmentally friendly and biodegradable.
Background Although it is a useful metric for preoperative risk stratification, frailty can be difficult to identify in patients before surgery. We sought to develop a preoperative frailty-risk model ...combining sarcopenia with clinical parameters to predict 1-year mortality using a cohort of patients undergoing gastrointestinal cancer surgery. Study Design We identified 1,326 patients undergoing hepatobiliary, pancreatic, or colorectal surgery between 2011 and 2014. Sarcopenia defined by psoas density was measured using preoperative cross-sectional imaging. Multivariable Cox regression analysis was performed to identify preoperative risk factors associated with 1-year mortality and used to develop a preoperative risk-stratification score. Results Among all patients identified, 640 (48.3%) patients underwent pancreatic surgery, 347 (26.2%) underwent a hepatobiliary procedure, and 339 (25.5%) a colorectal procedure. Using sex-specific cut-offs, 398 (30.0%) patients were categorized as sarcopenic. Sarcopenic patients were more likely to develop postoperative complications vs non-sarcopenic patients (odds ratio OR 1.80, 95% CI 1.42 to 2.29; p < 0.001). Overall 1-year mortality was 9.4%. On multivariable analysis, independent risk factors for 1-year mortality included increasing age (65 to 75 years: hazard ratio (HR) 1.81, 95% CI 1.05 to 3.14 greater than 75 years HR 2.79, 95% CI 1.55 to 5.02), preoperative anemia hemoglobin < 12.5 g/dL (HR 1.68, 95% CI 1.17 to 2.40), and preoperative sarcopenia (HR 1.98, 95% CI 1.36 to 2.88; all p < 0.05). Using these variables, a 28-point weighed composite score was able to stratify patients by their risk for mortality 1 year after surgery (C-statistic = 0.70). The proposed score outperformed other indices of frailty including the modified Frailty Index (C-statistic = 0.55) and the Eastern Cooperative Oncology Group (ECOG) performance score (C-statistic = 0.57) (both p < 0.05). Conclusion Sarcopenia was combined with clinical factors to generate a composite risk-score that can be used to identify frail patients at greatest risk for 1-year mortality after gastrointestinal cancer surgery.
Automotive Solid oxide fuel cells (SOFCs) require improvements in mechanical robustness, power generation at low temperatures, and system compactness. To address these issues, we attempt to improve ...the internal reformation of metal-supported SOFCs (MS-SOFCs) via catalyst infiltration. After introducing nickel/gadolinium-doped ceria (Ni/GDC) nanoparticles, power densities of 1.16 Wcm−2 with hydrogen (3%H2O) and 0.85 Wcm−2 with methane (Steam-to-Carbon ratio, S/C = 1.0) are obtained at 600 °C, 0.7 V. This is the highest performance achieved in previous studies on MS-SOFCs. Internal reforming with various hydrocarbon is also demonstrated. In particular 0.64 Wcm−2 at 600 °C, 0.7 V is obtained when the fuel is iso-octane. We develop a numerical model to separately analyze reforming and electrochemical reaction. Catalyst infiltration dramatically increases the number of active sites for steam reforming. In addition, ruthenium/gadolinium-doped ceria (Ru/GDC) should be suitable as a catalyst metal at low temperatures because of the lower activation energy of steam reforming.
•Ru/GDC or Ni/GDC catalyst has been infiltrated to metal-supported SOFCs.•Catalyst infiltration improves hydrogen reduction reaction and internal methane reforming.•The highest performance in previous studies on metal-supported SOFCs is obtained.•Infiltrated Ni/GDC enables internal reformation using natural gas, propane and iso-octane.•Increase of the number of active sites for steam reforming is found using numerical model.
Nanocellulose is a promising new membrane material for fuel cells, with much lower cost and environmental impact compared with Nafion or Aquivion. It is mechanically strong, is an excellent hydrogen ...barrier and has reasonable proton conductivity. Here, sulfonation of cellulose nanofibers is performed to enhance the conductivity (up to 2 × 10
− 3
S cm
− 1
) without compromising the membrane integrity, and fuel cells are fabricated with 30 µm-thick “paper” membranes. The hydrogen crossover current is two orders of magnitude lower than for Nafion fuel cells with equivalent thickness, but the power density is rather low. Spray-coating is used to deposit 8 µm-thick membranes directly onto the electrocatalyst layer, in a process analogous to 3D printing or additive manufacturing. The resulting paper fuel cell has high current density (> 0.8 A cm
− 2
) and power density (156 mW cm
− 2
) under standard measurement conditions (H
2
/air; 80°C; 95% RH; 0.1 MPa), attributed to decreased membrane resistance. The cost of the spray-painted cellulose membranes is calculated to be ~ 50 $ m
− 2
, which is much lower than that of Nafion, even without taking into consideration economies of scale. This new concept in electrochemical energy conversion paves the way for the mass production of affordable, recyclable fuel cells.
Graphic abstract
Solid oxide fuel cells (SOFCs) are promising electrochemical devices that enable the highest fuel-to-electricity conversion efficiencies under high operating temperatures. The concept of multi-stage ...electrochemical oxidation using SOFCs has been proposed and studied over the past several decades for further improving the electrical efficiency. However, the improvement is limited by fuel dilution downstream of the fuel flow. Therefore, evolved technologies are required to achieve considerably higher electrical efficiencies. Here we present an innovative concept for a critically-high fuel-to-electricity conversion efficiency of up to 85% based on the lower heating value (LHV), in which a high-temperature multi-stage electrochemical oxidation is combined with a proton-conducting solid electrolyte. Switching a solid electrolyte material from a conventional oxide-ion conducting material to a proton-conducting material under the high-temperature multi-stage electrochemical oxidation mechanism has proven to be highly advantageous for the electrical efficiency. The DC efficiency of 85% (LHV) corresponds to a net AC efficiency of approximately 76% (LHV), where the net AC efficiency refers to the transmission-end AC efficiency. This evolved concept will yield a considerably higher efficiency with a much smaller generation capacity than the state-of-the-art several tens-of-MW-class most advanced combined cycle (MACC).
The effects of strain on the ionic conductivity of rare-earth substituted CeO2 have been extensively studied, but the results have been inconsistent and focused upon the ‘optimised’ conductors such ...as Gd or Sm substituted CeO2 where defect association is minimised. By thermally annealing epitaxial films deposited by pulsed laser deposition, we varied the strain systematically, whilst avoiding any influence from interfacial or grain boundary effects. The activation energy of the in-plane conductivity was found to increase with increasing compressive biaxial strain, which was quantitatively in excellent agreement with previous computational and experimental studies. These results provide a much needed quantitative consensus on the effects of lattice strain on ionic transport. Furthermore, we demonstrate that the change in the activation energy for Yb-substituted CeO2 is around three times that for Gd or La substitutions for the same applied strain, indicating the important role played by defect association. These results have significant implications for ionic transport at reduced or ambient temperatures, where changes in conductivity due to strain may be several orders of magnitude larger for ‘non-optimised’ conductors compared with ‘optimised’ conductors. We rationalise our results by considering the defect-defect interactions in these materials and through force-field calculations.
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Porous Pt electrocatalysts have been developed as an example of carbon-free porous metal catalysts in anticipation of polymer electrolyte membrane (PEM) fuel cells and PEM water electrolyzers through ...the assembly of the metal precursor and surfactant. In this study, porous Pt was structurally evaluated and found to have a porous structure composed of connected Pt particles. The resulting specific electrochemical surface area (ECSA) of porous Pt was 12.4 m
g
, which was higher than that of commercially available Pt black. Accordingly, porous Pt showed higher oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activity than Pt black. When the activity was compared to that of a common carbon-supported electrocatalyst, Pt/ketjen black (KB), porous Pt showed a comparable ORR current density (2.5 mA cm
at 0.9 V for Pt/KB and 2.1 mA cm
at 0.9 V for porous Pt), and OER current density (6.8 mA cm
at 1.8 V for Pt/KB and 7.0 mA cm
at 1.8 V), even though the ECSA of porous Pt was only one-sixth that of Pt/KB. Moreover, it exhibited a higher durability against 1.8 V. In addition, when catalyst layers were spray-printed on the Nafion
membrane, porous Pt displayed more uniform layers in comparison to Pt black, showing an advantage in its usage as a thin layer.
Background Although sarcopenia has been identified as a predictor of poor, postoperative, clinical outcomes, the financial impact of sarcopenia remains undetermined. We sought to evaluate the ...relationship between sarcopenia and hospital finances among a cohort of patients undergoing a hepato-pancreatico-biliary or colorectal resection. Methods Clinical, financial, and morphometric data were collected for 1,169 patients undergoing operative resection between January 2011 and December 2013 at the Johns Hopkins Hospital. Multivariable regression analysis was performed to assess the relationship between sarcopenia and total hospital costs. Results Using sex-specific cutoffs for total psoas volume, 293 patients were categorized as sarcopenic. The presence of sarcopenia was associated with a $14,322 increase in the total hospital cost (median covariate-adjusted cost, sarcopenia versus no sarcopenia: $38,804 vs $24,482, P < .001). Patients who presented with sarcopenia demonstrated a higher total hospital cost within the subgroup of patients who developed a postoperative complication (sarcopenia versus no sarcopenia: $65,856 vs $59,609) and among those patients who did not develop a postoperative complication (sarcopenia versus no sarcopenia: $26,282 vs $23,763, both P < .001). Similarly, total hospital costs were higher among patients presenting with sarcopenia regardless of the length of stay for index admission (observed:expected, length of stay < 1: sarcopenia versus no sarcopenia: $25,038 vs $22,827; observed:expected, length of stay > 1: sarcopenia versus no sarcopenia: $43,283 vs $38,679, both P < .001). Conclusion As measured by sarcopenia, patient frailty is inversely related to total hospital costs. Sarcopenia represents a novel tool for forecasting patient outcomes and operative costs and can be used to inform quality improvement and cost containment strategies.
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