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Cost-effectiveness of reversible and conventional solid oxide electrolyzers in electricity-hydrogen integrated energy replenishment systems: A case study from China
Get PDFThe solid oxide electrolyzer cell (SOEC) achieves high system-level energy conversion efficiency through high-temperature operation, presenting significant application potential in electricity-hydrogen integrated energy replenishment systems. This study evaluates the economics of two technology pathways: the SOEC and battery energy storage system (BESS)-based system, and the reversible solid oxide cell (RSOC)-based system. A lifecycle cost assessment model is developed. Sensitivity analysis and Monte Carlo simulation are then employed to evaluate economic performance under baseline, high-electric-load, and high-hydrogen-load scenarios. Results indicate that under current technological and cost parameters, the annualized cost of the RSOC-based system is 1.4–1.55 times that of the SOEC + BESS-based system across all evaluated scenarios, with the cost gap narrowing as the proportion of hydrogen load increases. In the high-hydrogen-load scenario, technology advancement analysis shows that economic competitiveness for the RSOC requires a 30 % reduction in investment cost when its extended service life eliminates one stack replacement compared to the SOEC + BESS case. When replacement frequencies are equal, the required cost reduction increases to 42–60 %. These quantified results provide critical reference points for setting technology parameters and designing electricity-hydrogen integrated energy replenishment systems
NNLO QCD predictions for jet observables in ZH production at electron-positron colliders
Get PDFWe present precise predictions for a variety of jet observables in ZH production at electron-positron colliders, with the Z boson decaying leptonically and the Higgs boson decaying into two hadronic jets, up to NNLO in perturbative QCD. We consider a Higgs boson decaying into bottom (charm) quark pairs via Yukawa interaction and into gluons via an effective vertex in the limit of infinite top quark mass. We present results for the two decay modes separately, highlighting relevant differences in the differential distributions, and for the sum of all decay channels, including a comparison between different choices of the Durham (or kT) jet resolution parameter
The rest-ultraviolet to infrared spectral energy distributions of heavily reddened quasars are ‘V-shaped’ and hot-dust poor
Get PDFWe present a rest-ultraviolet to infrared spectral energy distribution (SED) analysis of 63 heavily reddened quasars (HRQs) at redshifts and with dust extinctions . Our analysis demonstrates that SEDs with red optical and blue ultraviolet (UV) continua are very common in HRQs, with 82 per cent of the sample showing a UV-excess relative to the reddened quasar continuum. We model the SEDs by combining a reddened quasar and an unobscured scattered light component, though contributions from a star-forming host galaxy cannot be ruled out. The average scattering fraction is small (0.3 per cent). Higher scattering fractions are ruled out by the colour-cut used to select HRQs, which pre-dates the discovery of the James Webb Space Telescope ‘Little Red Dot’ (LRD) population. Hence, LRDs generally have bluer UV continua. Nevertheless, four HRQs satisfy the LRD UV/optical continuum slope selections and are therefore massive cosmic noon analogues of LRDs. Analysis of the near-infrared SEDs of HRQs reveals a deficit of hot dust relative to blue quasars, similar to what is observed in LRDs. This suggests HRQs trace a phase where strong active galactic nucleus feedback processes eject dust from the inner torus. The UV scattering fraction of HRQs is weakly correlated with the amount of hot dust emission and anticorrelated with the line-of-sight extinction, . This is consistent with the hot dust acting as the scattering medium, and the line-of-sight extinction being dominated by dust on interstellar medium scales in the host galaxy
A galactic tug-of-war: how (not) to simultaneously fit the Milky Way satellite luminosity function and the mass–metallicity relation
Get PDFThe satellite population of the Milky Way is shaped by a range of astrophysical processes including mergers, star formation, feedback, and cosmic reionization. Determining which processes most strongly influence its properties is challenging and a key test of galaxy formation models. We train a neural network on the galform semi-analytic model and apply a variance-based sensitivity analysis to characterize the influence of 11 astrophysical parameters on two key observables: the satellite luminosity function, and the mass–metallicity relation. We find that: (1) the abundance of bright satellites () is regulated by supernova feedback; (2) the faint end of the luminosity function is shaped by the interplay between feedback and reionization; and (3) the mass–metallicity relation is governed almost exclusively by feedback at all masses. We do not find a combination of parameters in the fiducial model that fits the observed data for both statistics simultaneously. To understand why, we employ SHapley Additive exPlanations to capture the directionality of each parameter variation. This enables us to pinpoint the origin of tensions in the model, showing that parameter adjustments that regulate the abundance of faint satellites drive stellar metallicities to be an order of magnitude too low and vice versa. This ‘tug-of-war’ leads us to consider extensions to the baseline model, such as metal loading in winds, or allowing the feedback strength to evolve with redshift. Our study highlights the value of interrogating complex physical models through a sensitivity analysis framework by revealing high-order parameter interactions and non-linear responses that traditional one-at-a-time variations would miss
Passive hyperthermia increases blood circulation in specific regions, largely independent of conduit artery mechanics and cardiac performance
Get PDFPassive hyperthermia increases net peripheral and systemic blood flow in humans and other animals, yet the underlying haemodynamic forces that selectively accelerate blood movement remain incompletely characterized. Wave intensity analysis offers insight into the respective contributions of the heart and the vascular system to changes in blood circulation during physiological stress; however, the specific impact of hyperthermia on wave intensity metrics has not been elucidated comprehensively. To address this, we investigated wave speed and wave intensity parameters in the common carotid artery, along with local arterial distensibility in the internal carotid, brachial and common femoral arteries, in addition to total arterial compliance, in eight healthy males across four protocols: (1) 3 h of control measurements in normothermic conditions; (2) 3 h of one‐leg heating; (3) 3 h of two‐leg heating; and (4) 2.5 h of whole‐body heating. Forward compression (1.5‐fold; P = 0.041) and forward expansion (5.2‐fold; P < 0.0001) waves in the common carotid artery (indices of ventricular contractility and late‐systolic blood flow deceleration, respectively) increased exclusively during whole‐body heating. In contrast, backward compression waves, wave speed, distensibility and reflection index remained unaltered across all conditions. Notably, distensibility in the major conduit arteries perfusing the brain (internal carotid artery), forearm (brachial artery) and leg (common femoral artery), in addition to total arterial compliance, remained unchanged across all conditions. Collectively, these findings suggest that increases in blood circulation within specific regions of the human body during passive hyperthermia are largely independent of conduit artery mechanics and cardiac performance
The Second Council of Toledo (527/531): Introduction and Annotated Translation
No full textThis article offers a translation of and commentary on the Second Council of Toledo, inaugurating a new, collaborative project to translate the Church councils of late antique Iberia. I begin by considering the context of the synod, which took place during the period of Arian kingship and Ostrogothic overlordship in Iberia. I then outline the three main lines of transmission of its text in the sixth- and seventh-century conciliar compilations known as the Collectio Hispana, Collectio Novariensis, and Epitome Hispana, before noting the implications for dating the Council and reconstructing its contents. I argue for a date of 531 over 527 and for the priority of the Collectio Novariensis and Epitome Hispana over the Collectio Hispana, which affects how we should read the distinct lists of subscribing bishops in the manuscripts. Finally, I review the five canons decreed by the Council on child oblation and education, clerical hierarchy and celibacy, usufruct of Church property, and incestuous relations as a preface to the Latin text and English translation
Teaching social innovation through place-based learning: Facilitating perspective sharing in co-creating social value
Get PDFSocial innovation education has become an increasingly prominent means through which higher education institutions seek to create positive societal impact. One approach is through place-based learning, in which students are enabled to achieve learning outcomes through experiential work in the community. Although addressing real-world problems is widely regarded as beneficial for participant organizations, communities, and learners, less is understood about how such engagement is transformed into shared social value. Our research explored how place-based learning in social innovation education creates shared social value. Drawing on an analysis of 82 projects conducted across six annual cycles of place-based learning, we develop a model of social value co-creation that illustrates how educators’ facilitation of collaboration between key stakeholders (practitioners, educators, and students) lies at the heart of successful social innovation education. The model captures a contextualized understanding of the different perspectives involved in place-based learning, thereby advancing understanding of the co-creation of social value and its significance for both researchers and educators in social innovation education
Evolution of fabric anisotropy of granular soils: x-ray tomography measurements and theoretical modelling
No full textFabric anisotropy is a key component to understand the behaviour of granular soils. In general, experimental data on fabric anisotropy for real granular soils are very limited, especially in the critical state. In this paper, x-ray tomography measurements are used to provide experimental data on contact fabric anisotropy inside shear bands for two granular soils. The data are then used to assess the validity of Anisotropic Critical State Theory (ACST) and the accuracy of a fabric evolution law that was previously developed from the results of DEM simulations on idealised materials. Overall, the experimental results support ACST according to which unique (i.e., independent of initial conditions) values for fabric anisotropy and coordination number are observed at large strains. With increasing roundness of the material, the rate at which the critical state is approached increases. The evolution of fabric anisotropy measured from the experiments is fairly well reproduced by the proposed evolution law
Stereotype Threat and Alienation
Get PDFIn this article, I expand our understanding of the normative profile of stereotype threat and point where to take that inquiry next. My focus is the realization of the threat of stereotype threat, a phenomenon I call succumbing to stereotype threat. I show that in cases of stereotype threat that present us with the threat of what Sally Haslanger identifies as epistemic self-objectification, succumbing to stereotype threat is characterized by a corrupt relation of the individual to herself. That baneful relation, I argue, is what stereotype threat is a threat of. We also learn that that relation is facilitated by the individual’s social environment, in which the individual is an active participant. The individual, then, contributes to the forces that set her against herself. That social dimension is the area that stands in need of further investigation. To carry on that task, I suggest we harness the notion of alienation as understood by Marx. This notion neatly captures the corrupt relationship at the heart of succumbing to stereotype threat while acknowledging the individual’s role in the social forces that contribute to that plight; and it is a notion that is nested in a tradition that is well attuned to the ontological and normative nuances of social environment. The notion of alienation, then, lends a name to the wrong of succumbing to stereotype threat and thus to the threat of stereotype threat, and it has the credentials to lead further research into those phenomena
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