The polymer electrolyte membrane (PEM) fuel cell technology offers many advantages over other types of fuel cells in terms of high power density, low operating temperature and fast start, stop and ...load following capability. However, the stringent fuel quality requirements still remain a critical barrier for its commercialization. In this context, gaining knowledge on the effect of fuel compositions on the performance of the PEM fuel cells is essential to determine the fuel cleaning requirements for reformates from different fuel sources. In this paper, a test facility is described which has been established to study fuel quality issues, start, stop, thermal cycling and load following capabilities of PEM fuel cell stacks up to 3 kW
e capacity. Important features of the test facility are described along with results of testing commercial and in-house built stacks up 1 kW
e capacity.
During the 1970s and 1980s, economic and financial crime turned into a societal issue in Switzerland. The perpetrators of white-collar crime often enjoyed total impunity: legal proceedings were very ...time consuming, authorities in charge of judicial investigation were under-resourced. This paper investigates how the political and judicial authorities responded to this challenge. By the end of the 1980s, a strong shift towards a more specialized handling of financial crime by public prosecutors occurred. Specialized departments were set up and judges were trained in commercial matters. This transformation breached with a long tradition of leniency and inefficient judicial handling of economic crime. Based on archival evidence, this paper sheds new light on the drivers of an institutionalization process which affected not only the Swiss financial centre, but also all the global judicial proceedings which relied on it. Professionalizing the response to financial crime also aimed at restoring the corporate reputation of Swiss financial firms, in a context of growing competition among offshore financial centers.
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•Carbon/hydrocarbon assisted water electrolysis reviewed for clean hydrogen production.•Reviewed different electrochemical technologies using carbon fuels under development.•This ...technology has been progressed to different levels of maturity for different carbon sources.•This route of hydrogen production can lower the electric input and CO2 emissions from the carbon sources.
Hydrogen is mainly produced by natural gas reforming, which is a highly efficient process with low feedstock costs. However, the rising interest in clean technologies will increase the demand for hydrogen, meaning that other sources will need to be explored. Although coal is currently the major source of power generation, its demand appears to be declining due to the rise in electricity generated from renewable energy sources and the worldwide quest for low-emission power generation. Coal reserves worldwide are abundant, but new technologies would be needed to produce hydrogen from this feedstock. Coal gasification is one well-established technology for this purpose, but it is inefficient and produces high CO2 emissions. An alternative technology that has been investigated over the past few decades is carbon assisted water electrolysis. The basic process is water/steam electrolysis, with part of the energy required for the electrolysis provided by the chemical energy of coal, which reduces the overall electrical energy input. In addition to coal, the process can also use other carbon sources, such as biomass, alcohols or gaseous hydrocarbons. Several studies have investigated this electrochemical route of hydrogen production, employing different electrolytes in a wide temperature range (room temperature to 850 °C) under different process conditions. This paper presents a comprehensive review of carbon assisted water electrolysis, associated materials used and the challenges for the development of the technology at the commercial scale.
The major technologies being considered for the green hydrogen production are polymer electrolyte membrane (PEM) and solid oxide electrolysis (SOE). While PEM electrolysis technology is nearing ...commercialisation with units now being globally installed at tens of MW scale, SOE technology is still under development with units available only at 100s of kW scale and at much higher costs per kW. SOE due to its high operating temperatures (close to 800 °C) has the potential to reduce the electric energy input by up to 30% for the hydrogen production per tonne by using the low-cost thermal energy input available from the industrial or downstream synthesis processes. The SOE cathode, where steam electrolysis occurs, plays a crucial role in dictating the cell voltage losses and the stability of the cell operation that eventually has a large impact on the SOE efficiency and lifetime. The current state-of-the-art cathode materials based on Ni-YSZ pose many challenges. There is, therefore, a global effort to find alternative cathode materials suitable for steam electrolysis in SOE. This review critically reviews novel nanoengineered cathode materials and points to the fact that such materials synthesized using infiltration and exsolution techniques, in combination with advanced materials characterisation like high-temperature scanning probe microscopy and in situ Raman spectroscopy can be a right approach to find the suitable cathode materials for steam electrolysis in SOE. This, however, may need to be combined with a techno-economic analysis to provide the technical and economic viability of these materials for the SOE commercialisation.
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•High temperature steam electrolysis critically reviewed, focussing on cathode materials.•Conventional and alternative cathode materials briefed, and their challenges discussed.•Novel heterostructured materials and their drawbacks discussed in-depth.•Scope of further research around novel materials highlighted at the end.
•Cu-GDC cathodes tested for high temperature steam electrolysis.•Remarkably low polarisation resistance of 0.42 Ωcm2 at 1.60 V, 800 °C.•Optimum steam flow rate for maximum current density was ...governed by Cu wt%.
Rising concerns on CO2 emissions and depletion of fossil fuels have led to the quest for developing technologies that aim to produce hydrogen via renewables-powered zero-emission electrolytic pathways. Solid oxide electrolytic cell (SOEC) is such an emerging technology since it is expected to produce higher electric efficiency compared to other state-of-the-art electrolysers like proton exchange membrane (PEM) and alkaline electrolytic cell (AEL). However, SOEC technology is limited by a dearth of high-temperature redox stable electrocatalytically active cathode materials and is currently relying mainly on the materials used as fuel electrodes in solid oxide fuel cells (SOFC). This work investigates the electrochemical performance of three different cathodes comprising cermets of copper and gadolinia doped ceria (Cu-GDC) for steam electrolysis at 800 °C in tubular SOEC under varying steam flow conditions and applied voltages. Remarkably, a polarisation resistance as low as 0.42 Ωcm2 was obtained at 1.60 V with a corresponding Faradaic efficiency more than 95%. A comparison of the trends depicted by current density versus steam flow rate clearly indicated that at any operating temperature, optimum steam flow rate required for maximum current density was governed by the concentration of electrocatalytically active sites. Similarly, a comparison of the voltage-current characteristics of both the cells revealed that Cu content as low as 30 wt% can impart sufficient electronic conductivity as well as catalytic activity to achieve current densities only 15–20% lower than what is obtained with 70 wt% Cu. Finally, 90 min short-term testing of both the cells at 1.60 V under 23% H2/77% steam (v/v) indicated no signs of performance degradation.
With the rapidly declining cost of renewable energy, efficient ways are needed for its transportation between different regions. Hydrogen is becoming a major energy vector, with the key challenges of ...its storage and transportation commonly overcome by using ammonia for chemical storage of hydrogen energy. Ammonia, which is more energy dense than hydrogen and easier to transport, is a carbon-free alternative fuel that can be used in a variety of ways to generate power. Owing to their robustness and efficiency, solid-oxide fuel cells (SOFC) stand out as one of the most promising technologies that convert ammonia to electricity. Unlike other fuel cells, such as polymer electrolyte membranes, SOFCs do not require the fuel to be cleaned by energy-intensive external cracking and extensive cleaning; their high operating temperature provides the flexibility to crack the ammonia inside the anode or to use it directly. Here, we discuss experimental and numerical studies of ammonia SOFCs and critically review the status and opportunities for ammonia-fuelled SOFC technology. In the first section, we briefly outline the potential cathode and electrolyte materials for SOFCs. Only the anode component poses additional challenges with ammonia over the well-established hydrogen-fuelled SOFC technology, and this topic has been addressed in detail. Anode catalysts for ammonia decomposition, parameters affecting ammonia decomposition and anode catalyst degradation are also discussed. In the second section, we review the modelling studies for ammonia SOFCs. Finally, we run through the major commercial initiatives and demonstrations in green ammonia production and ammonia SOFCs.
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•The recent developments of ammonia fuelled SOFCs are presented.•Anode design parameters affecting NH3 decomposition in anode are discussed.•Cell performance degradation and anode poisoning while using NH3 fuel are presented.•Reviewed cell performance models including the NH3 decomposition kinetics in anode.•The technology status and recent demonstrations are outlined.
En 1934, l’Assemblée fédérale adopte la première législation qui soumet les banques à un régime de régulation spécifique en Suisse. Une autorité de contrôle, la Commission fédérale des banques – ...ancêtre de la FINMA actuelle – est mise en place. Ce livre examine l’environnement réglementaire sur lequel la forte croissance du secteur bancaire helvétique au cours du XXe siècle a reposé. Il analyse d’une part les difficiles conditions d’émergence d’une législation fédérale relative à l’activité des banques. Ce n’est qu’avec la profonde crise financière des années 1930 que la résistance des milieux bancaires à une réglementation est vaincue. Le livre se concentre d’autre part sur l’évolution des activités de la nouvelle instance de régulation (1935-1971). En quoi le choix d’un organisme aux faibles ressources et aux pouvoirs d’intervention limités a-t-il influencé la régulation mise en œuvre ? Mettre en lumière le rôle des superviseurs bancaires permet d’éclairer les relations entre l’Etat et un secteur décisif de son économie. L’analyse historique contribue aussi à réintégrer certaines problématiques rendues actuelles par la crise de 2008 dans une perspective de plus longue durée.
Skin cancer, including malignant melanoma (MM) and keratinocyte carcinoma (KC), historically named non-melanoma skin cancers (NMSC), represents the most common type of cancer among the white skin ...population. Despite decades of clinical research, the incidence rate of melanoma is increasing globally. Therefore, a better understanding of disease pathogenesis and resistance mechanisms is considered vital to accomplish early diagnosis and satisfactory control. The "Omics" field has recently gained attention, as it can help in identifying and exploring metabolites and metabolic pathways that assist cancer cells in proliferation, which can be further utilized to improve the diagnosis and treatment of skin cancer. Although skin tissues contain diverse metabolic enzymes, it remains challenging to fully characterize these metabolites. Metabolomics is a powerful omics technique that allows us to measure and compare a vast array of metabolites in a biological sample. This technology enables us to study the dermal metabolic effects and get a clear explanation of the pathogenesis of skin diseases. The purpose of this literature review is to illustrate how metabolomics technology can be used to evaluate the metabolic profile of human skin cancer, using a variety of analytical platforms including gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR). Data collection has not been based on any analytical method.
The major applications of PGMs are as catalysts in automotive industry, petroleum refining, environmental (gas remediation), industrial chemical production (e.g., ammonia production, fine chemicals), ...electronics, and medical fields. As the next generation energy technologies for hydrogen production, such as electrolysers and fuel cells for stationary and transport applications, become mature, the demand for PGMs is expected to further increase. Reserves and annual production of Ru, Rh, Pd, Ir, and Pt have been determined and reported. Based on currently available resources, there is around 200 years lifetime based on current demand for all PGMs, apart from Pd, which may be closer to 100 years. Annual primary production of 190 t/a for Pt and 217 t/a for Pd, in combination with recycling of 65.4 t/a for Pt and 97.2 t/a for Pd, satisfies current demand. By far, the largest demand for PGMs is for all forms of catalysis, with the largest demand in auto catalysis. In fact, the biggest driver of demand and price for Pt, Pd, and Rh, in particular, is auto emission regulation, which has driven auto-catalyst design. Recovery of PGMs through recycling is generally good, but some catalytic processes, particularly auto-catalysis, result in significant dissipation. In the US, about 70% of the recycling stream from the end-of-life vehicles is a significant source of global secondary PGMs recovered from spent auto-catalyst. The significant use of PGMs in the large global auto industry is likely to continue, but the long-term transition towards electric vehicles will alter demand profiles.
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