On physical nanoscale aspects of compatibility of steels with hydrogen and natural gas

The possibilities of effective solutions of relevant technological problems are considered based on the analysis of fundamental physical aspects, elucidation of the nano-structural mechanisms and interrelations of aging and hydrogen embrittlement of materials (steels) in the hydrogen industry and gas-main industries. The adverse effects which these mechanisms and processes have on the service properties and technological lifetime of materials are analyzed. The concomitant fundamental process of formation of carbohydride-like and other segregation nanostructures at dislocations (with the segregation capacity 1 to 1.5 orders of magnitude greater than in the widely used Cottrell 'atmosphere' model) and grain boundaries is discussed in the context of how these nanostructures affect technological processes (aging, hydrogen embrittlement, stress corrosion damage, and failure) and the physicomechanical properties of the metallic materials (including the technological lifetimes of pipeline steels)

A more effective coordinate system for parameter estimation of precessing compact binaries from gravitational waves

Ground-based gravitational wave detectors are sensitive to a narrow range of frequencies, effectively taking a snapshot of merging compact-object binary dynamics just before merger. We demonstrate that by adopting analysis parameters that naturally characterize this 'picture', the physical parameters of the system can be extracted more efficiently from the gravitational wave data, and interpreted more easily. We assess the performance of MCMC parameter estimation in this physically intuitive coordinate system, defined by (a) a frame anchored on the binary's spins and orbital angular momentum and (b) a time at which the detectors are most sensitive to the binary's gravitational wave emission. Using anticipated noise curves for the advanced-generation LIGO and Virgo gravitational wave detectors, we find that this careful choice of reference frame and reference time significantly improves parameter estimation efficiency for BNS, NS-BH, and BBH signals.Comment: 11 pages, 5 figures, submitted to Phys. Rev.

Advanced LIGO's ability to detect apparent violations of the cosmic censorship conjecture and the no-hair theorem through compact binary coalescence detections

We study the ability of the advanced Laser Interferometer Gravitational-wave Observatory (aLIGO) to detect apparent violations of the cosmic censorship conjecture and the no-hair theorem. The cosmic censorship conjecture, which is believed to be true in the theory of general relativity, limits the spin-to-mass-squared ratio of a Kerr black hole. The no-hair theorem, which is also believed to be true in the theory of general relativity, suggests a particular value for the tidal Love number of a non-rotating black hole. Using the Fisher matrix formalism, we examine the measurability of the spin and tidal deformability of compact binary systems involving at least one putative black hole. Using parameter measurement errors and correlations obtained from the Fisher matrix, we determine the smallest detectable violation of bounds implied by the cosmic censorship conjecture and the no-hair theorem. We examine the effect of excluding unphysical areas of parameter space when determining the smallest detectable apparent violations, and we examine the effect of different post-Newtonian corrections to the amplitude of the compact binary coalescence gravitational waveform. In addition, we perform a brief study of how the recently calculated 3.0 pN and 3.5 pN spin-orbit corrections to the phase affect spin and mass parameter measurability. We find that physical priors on the symmetric mass ratio and higher harmonics in the gravitational waveform could significantly affect the ability of aLIGO to investigate cosmic censorship and the no-hair theorem for certain systems.Comment: 21 pages, 7 figures, 6 table

Exploring an Unfamiliar Space Reflections on the Socio-Psychological Aspects of Synchronous Online Teaching

[EN] Online technologies provide a myriad of new teaching and learning methods, and while those new technologies have a lot of advantages, the rapid change from face-to-face to online teaching and distance learning during the COVID-19 pandemic has made certain disadvantages visible, too. This paper focuses on the psychological impact of online learning on students, specifically in connection with the move from a well-known place, the university campus, to an unknown space, the online classroom. It explores why uncertainty and anxiety can result in reluctance to engage, a process that is caused by a lack of social information, low peer bonding possibilities and obstacles to create a sense of belonging. The findings are based on a general, theoretical understanding of psychological aspects that impact the virtual classroom, as well as on observations made during the lockdown period and its subsequent months of online teaching, drawing on concepts from social psychology, i.e. social cognition, social perception and conformity. What has become undoubtedly evident is that while the new technologies create new and creative spaces for teaching and learning, they are by no means free of stress and anxiety.Ochsner, A. (2021). Exploring an Unfamiliar Space Reflections on the Socio-Psychological Aspects of Synchronous Online Teaching. En 7th International Conference on Higher Education Advances (HEAd'21). Editorial Universitat Politècnica de València. 703-710. https://doi.org/10.4995/HEAd21.2021.12909OCS70371

Identifying Research Quality in the Social Sciences

What is good research? A seemingly simple question reveals itself difficult to answer. The current methods for identifying research quality come with validity issues due to a lack of conceptual scrutiny. I argue that research quality is a context dependent latent construct. While identifying research quality is a difficult task, it is not impossible. The methodological toolbox of the social sciences provides instruments to capture such latent constructs. I propose a method to conceptualise research quality in its context and argue that it is fruitful to combine peer review and indicator-based evaluations rather than playing them off against each other. Similarly, instead of juxtaposing notions of quality of different stakeholders, it is more promising to start from the scholars’ notions of quality and to add other stakeholders’ notions of quality in a communicative process arriving at a context-specific definition of research quality

Examining the relationship between daily changes in support and smoking around a self-set quit date

This study was funded by the Swiss National Foundation (100014_124516). We would like to thank all students who helped with data collection.Peer reviewedPostprin