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Jan Miodek, Włodzimierz Wysoczański (Wrocław: Wydawnictwo WTN, 2013). 4 E.g. Joanna Bielska-Krawczyk, Między widzialnym a niewidzialnym. ... Herling-Grudziński, W. Bolecki, op. cit., 168. ...doi:10.32798/pflit.96 fatcat:jkf7cseosfadlppxfavjhqiaqe
This deliverable presents the activities carried out within the task WT1.5. The objective is to provide in-depth insights and practical recommendations on how to operate the CH2P stack safely under constant conditions and the modulating CH2P modes. For this purpose, a literature review and on-field return of experience made in close collaboration with the technology manufacturer SP have been performed in the frame of task WT2.1 to select the major degradation phenomena that primarily affect thedoi:10.5281/zenodo.4700916 fatcat:lzgimc553jgc3kxsusyqfklfbq
more »... rimarily affect the stack efficiency and lifetime. The identified degradation mechanisms can be attributed to two main sources, namely the thermo-mechanical degradation, and the microstructural alterations. These two processes were both investigated by a validated modelling approach in a view to provide practical insights and recommendations for an optimal CH2P stack operation.
Chemical diffusion(D)and surface exchange(た)coef丘cients for SrFeO3 δwere measured using an electrochemical cell combined with electrochemical impedance spectroscopy(EIS)and potential step technique(PS)in the tempera− ture range of850−915℃.A1)value of-4・10−5cm2/s and aたvalue of-8・10−5cm/s were obtained at900℃.Slow scan(0.5−3μV/s)cyclic voltametry(CV〉was pe㎡ormed in the same temperature range and using the same electro− chemical cell to obtain oxygen nonstoichiometry data.The oxygendoi:10.5796/electrochemistry.68.444 fatcat:rfrl5ja6hrbprjok2w4abuzmbu
more »... xygen nonstoich玉ometry(δ)at900℃in air was deter− mined as O。4.A plateau corresponding toδ=0.5was observed below an oxygen partial pressure(ρ( 02 ))of10−6atm. These results were shown to be consistent with the literature data.Nonstoichiometry data were fUrther analysed us− ing the existing defect models,and the limits of the independent point defect approximation and the necessity of con− sidering interactions between point defects and clusters were established. κ砂W∂名肉 Strontium Ferrate/Ferrite;Oxygen transportl Oxygen nonstoichiometry l Intro4uction
Augmented video streams display information within the context of the physical environment. In contrast to Augmented Reality, they do not require special equipment, they can support many users and are location-independent. In this paper we are exploring the potentials of augmented video streams for remote participation. We present our design considerations for remote participation user interfaces, briefly describe their development and explain the design of three different applicationdoi:10.1145/1240866.1240915 dblp:conf/chi/WittkamperLBOHG07 fatcat:gt3j6ocglbdddetoffv7ujyy7i
more »... plication scenarios: watching a pervasive game, observing the quality of a production process and exploring interactive science exhibits. The paper also discusses how to develop high quality augmented video streams along with which information and control options are required in order to obtain a viable remote participation interface.
The reliability of solid oxide fuel cell (SOFC) systems is closing the gap to meet the requirements for market implementation. However, with the recent advances of the technology, the lifetime of SOFC stacks is becoming increasingly limited by mechanical failures, which need to be overcome for lowering costs. Numerical thermo-mechanical investigations are relevant to understand and predict potential failure modes in SOFC stacks, because of the complexity induced by the variety in materials,doi:10.5281/zenodo.4700559 fatcat:sdesnh7pnrckldroe3cvd6p27q
more »... y in materials, local conditions and effect of history. Standard finite-element (FE) stack modelling approaches commonly consider idealised components, i.e. computational domains imported from computer-aided design. To further advance the understanding of mechanical failure in the light of cost reductions, statistical variability in the dimensions and geometry of the produced stack components - because of imperfections in the manufacturing processes - must be accounted for. This study is focused on the effects of variability in the flatness of the metallic interconnect (MIC) on the distribution of the contact pressure over the active area. The component initial deformations are included in a 3-D thermo-mechanical model of a series of single repeating units (SRUs). The anisotropic elastic and creep properties of the gas-diffusion layer (GDL) materials are estimated by computational homogenization. This allows the modelling of the GDLs as simplified continuum geometries to reduce the stack simulation runtime. The stack conditioning procedure is simulated to account for the effects of the stack manufacturing on the stress-state before operation. After this initialisation step, the simulation of stack operation consists in importing temperature profiles from thermoelectrochemical simulations into the FE thermo-mechanical model. The simulated operation scenario is long-term polarisation in co-flow configuration, interrupted by thermal cycles. The simulation results show that MIC pre-deformation cause a less uniform distribution of [...]
Van Herle et al. ... Van Herle et al. Fig. 6 . 6 Primary particle size of 33YDC powders calcined at dierent temperatures, as obtained from XRD-LB estimation. ...doi:10.1016/s0272-8842(97)00007-2 fatcat:azhoqez5r5fxzlgd5my5gwwpq4
This study investigates the performance of a standard Ni-YSZ anode supported cell under ethanol steam reforming operating conditions. Therefore, the fuel cell was directly operated with a steam/ethanol mixture (3 to 1 molar). Other gas mixtures were also used for comparison to check the conversion of ethanol and of reformate gases (H 2 , CO) in the fuel cell. The electrochemical properties of the fuel cell fed with 4 different fuel compositions were characterized between 710 and 860°C by I-Vdoi:10.1016/j.jpowsour.2010.11.063 fatcat:n4hzgymjazfjlozjpmcgcfbzza
more »... and 860°C by I-V and EIS measurements at OCV and under polarization. In order to elucidate the limiting processes, impedance spectra obtained with different gas compositions were compared using the derivative of the real part of the impedance with respect of the natural logarithm of the frequency. Results show that internal steam reforming of ethanol takes place significantly on Ni-YSZ anode only above 760°C. Comparisons of results obtained with reformate gas showed that the electrochemical cell performance is dominated by the conversion of hydrogen. The conversion of CO also occurs either directly or indirectly through the water-gas shift reaction but has a significant impact on the electrochemical performance only above 760°C.
Size effects are discussed closer by Herbstová and Herle 8 . ... A creep of contacts of lumps (see Herbstová and Herle 8 ) can explain this effect. Furthermore, the decrease of hydraulic conductivity was observed at increasing stresses (see Fig. 3 -right). ...doi:10.1016/j.proeps.2014.06.011 fatcat:rdkwlhd5gvclplwv7j46tue5lm
Carbon capture and utilization are promising to tackle fossil-fuel depletion and climate change. CO2 hydrogenation can synthesize various chemicals and fuels, such as methanol, formic acid, urea, and methane. CO2-to-methanol integrated with solid-oxide electrolysis (SOE) process can store renewable power in methanol while recycling recovered CO2, thus achieving the dual purposes of storing excess renewable power and reducing lifetime CO2 emissions. This paper focuses on the techno-economicdoi:10.3390/en12193742 fatcat:3czl425phzfnvfbys3aphxhdvu
more »... echno-economic optimization of CO2 hydrogenation to synthesize green methanol integrated with solid-oxide electrolysis process. Process integration, techno-economic evaluation, and multi-objective optimization are carried out for a case study. Results show that there is a trade-off between energy efficiency and methanol production cost. The annual yield of methanol of the studied case is 100 kton with a purity of 99.7%wt with annual CO2 utilization of 150 kton, representing the annual storage capacity of 800 GWh renewable energy. Although the system efficiency is rather high at around at 70% and varies within a narrow range, methanol production cost reaches 560 $/ton for an electricity price of 73.16 $/MWh, being economically infeasible with a payback time over 13 years. When the electricity price is reduced to 47 $/MWh and further to 24 $/MWh, the methanol production cost becomes 365 and 172 $/ton with an attractive payback time of 4.6 and 2.8 years, respectively. The electricity price has significant impact on project implementation. The electricity price is different in each country, leading to a difference of the payback time in different locations.
Van herle et al. calculated the partial pressure of oxygen depending on the fuel utilization (F u ) for an open post-combustion design with counter flow, the so-called R-design. ...doi:10.3390/membranes2030585 pmid:24958298 pmcid:PMC4021905 fatcat:syd5iz5zkrbnpgiwznuebug5wm
The stack survives the degradation caused by perovskite/interconnect interaction. The degradation at the air side of the interconnect stabilizes after 5000 h. The tested SOFC stack is robust: it can withstand more than 120 thermal cycles. The results partially disaffirm the reliability of ex-situ tests on interconnects.doi:10.1016/j.ijhydene.2019.09.218 fatcat:nhmybkgajjcolgvntfqlf5ouae
ECS Proceedings Volumes
With a water based standard tape casting method, films of 0.7-10 pm YSZ were co-cast with 200-250 mm NiO/YSZ anode substrates and co sintered at 1350 °C. The electrochemical results of such samples, tested with a LSM/YSZ composite cathode are the following: the output power reached 580 mW/cm^ at 760 °C and 300 mW /cm^at 700°C. We observed an anode overpotential (on a 100 h test) less than 0.03 V at 1 A/cm^ at 760 °C and the total ohmic losses of the cell were below 0.1 Qcm^. The cathodedoi:10.1149/199740.0340pv fatcat:e3zdtcxfrna4nfcvn6fn44tq34
more »... The cathode overpotential (0.43 V at 1 A/cm^ at 750 °C) was found to be the output power limiting term.
Our implementation then uses a worker object to distribute the computations on as many CPU cores as available by applying individual parallel data subsets concurrently [Herling and Broll 2010] . ...doi:10.1145/1889863.1889868 dblp:conf/vrst/HerlingB10 fatcat:kqa7dehuwzhile76jpjncj72li
The influence of partial substitution of Fe with Ti on the oxygen transport properties of La 1−x Sr x FeO 3 membranes was investigated in view of their application for oxygen separation. Samples of composition La 0:5 Sr 0:5 Fe 1Ày Ti y O 3Àδ (y=0, 0.2) were prepared and their oxygen transport properties characterised by potential step relaxation and by oxygen permeation measurement in an air/ argon gradient. With the first technique, chemical diffusion ð e DÞ and surface exchange (k S )doi:10.1007/s10008-006-0133-z fatcat:4irsfksw6zf6begigkwp6f3thy
more »... ange (k S ) coefficients were obtained by fitting of the current relaxation data to a single expression valid over the complete time range. The Ti-substituted composition gave slightly larger values of e D and k S . The trend was opposite for the measured oxygen permeation flux. In the latter experience, ordering of oxygen vacancies was observed at lower temperature, reducing significantly the performance of the material.
This presentation described the modelling activities of the SWITCH system, conducted at EPFL. A morphological-based model is developed to simulate Ni agglomeration in Ni-YSZ fuel electrodes. A large range of microstructures are generated by the model simulating different degrees of Ni evolution. The model showed a good agreement with the experimental data acquired from real reconstructions.doi:10.5281/zenodo.4749493 fatcat:33stryrw3jcnpgvwfttp5xukqm
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