Miracle-dz/UniFAR-FTUs huggingface dataset:
Study on dehydrogenation behaviour of molten steel in single snorkel refining furnace (SSRF) by a mathematical model

A mathematical model of an industrial Single Snorkel Refining Furnace (SSRF) has been developed to investigate dehydrogenation behaviour in the vacuum refining process. Dehydrogenation reactions were considered to take place at three sites: Ar bubble surface, bath surface, and the bulk steel. The effects of Ar bubble behaviour and H2 heterogeneous nucleation behaviour of the bulk steel on dehydrogenation were taken into account specifically. The simulation results are in good agreement with the measured industrial data. Using the model, the dehydrogenation rate at different sites and its contribution to total dehydrogenation value were evaluated in detail. The results indicated that bulk steel dehydrogenation occurred only the high concentration range, while the other two reactions participated in the whole refining process. In addition, the effect of argon flow rate on the dehydrogenation rate was also obtained and the reasonable range of argon flow rate for SSRF treatment has been recommended.
Self-esteem and perceived social competence protect adolescent students against ostracism and loneliness

Abstract The purpose of this research was to examine the associations between self-esteem, perceived social competence, ostracism and loneliness among adolescent students. For the investigation of self-esteem and perceived social competence as key developmental constructs concerning negative experiences such as ostracism and loneliness, it is important to understand the experiences that may inhibit individual development in adolescence. Participants were 542 presecondary and secondary school students who completed the Rosenberg Self-Esteem Scale, the Perceived Social Competence Scale, the Ostracism Experience Scale for Adolescents, and the Loneliness Scale for Children. The data were analysed with Pearson moments correlation analysis and multiple regression analysis. Findings showed that: (1) self-esteem, perceived social competence, ostracism and loneliness were related to each other; (2) self-esteem and perceived social competence were negatively related to ostracism and loneliness; (3) ostracism had a positive relationship with loneliness and a negative impact on self-esteem; and (4) an increase in the level of perceived social competence predicted a decrease in the levels of ostracism and loneliness. The results were discussed in the light of relevant literature.
Highly efficient red electroluminescent polymers with dopant/host system and molecular dispersion feature: polyfluorene as the host and 2,1,3-benzothiadiazole derivatives as the red dopant

By selecting polyfluorene as the polymer host, choosing 2,1,3-benzothiadiazole derivative moieties as the red dopant units and covalently attaching 0.3 mol% of the dopant units to the side chain of the polymer host, we developed a novel series of red electroluminescent polymers of dopant/host system with molecular dispersion feature. Their EL spectra exhibited predominant red emission from the dopant units because of the energy transfer and charge trapping from the polymer backbone to the dopant units. The emission wavelength of the polymers could be tuned by modifying the chemical structures of the dopant units. Single-layer devices (device configuration: ITO/PEDOT : PSS/polymer/Ca/Al) of these polymers emitted red light with a peak at 615 nm, a luminous efficiency of 5.04 cd A−1 and an external quantum efficiency of 3.47%, or emitted deep-red light with a peak at 650 nm, a luminous efficiency of 1.70 cd A−1 and an external quantum efficiency of 2.75%. Their high EL efficiencies were due to the energy transfer and charge trapping from the host to the dopant units as well as the molecular dispersion of the dopant units in the host. Increase of the dopant unit content led to increased turn-on voltages and decreased EL efficiencies of the resulting devices.
Intrinsic and extrinsic Gilbert damping in exchange-biased IrMn/Cu/CoFe trilayer films

We studied the intrinsic and extrinsic Gilbert damping constants measured with an all-optical method in an exchange-biased IrMn/Cu/CoFe trilayer system with various Cu-spacer layer thicknesses. To understand the effect of the exchange bias on damping, the strength of the exchange bias was controlled by the Cu-spacer layer. When the external magnetic field is high enough compared with the exchange fields, the intrinsic Gilbert damping constant is independent of the exchange bias field. On the other hand, under a low external magnetic field, the extrinsic Gilbert damping is dominant because of the magnetic inhomogeneities, and is strongly correlated with the exchange bias field.
Simple Analytic Solutions for a Convectively Driven Walker Circulation and Their Relevance to Observations

We present a linear equation for the Walker circulation streamfunction and find its analytic solutions given specified convective heating. In a linear Boussinesq fluid with Rayleigh damping and Newtonian cooling, the streamfunction obeys a Poisson’s equation, forced by gradients in the meridionally averaged diabatic heating and Coriolis force. For an idealized convective heating distribution, analytic solutions for the streamfunction can be found through an analogy with electrostatics. We use these solutions to study the response of the Walker circulation strength (mass transport) to changes in the vertical and zonal scales of convective heating. Robust responses are obtained that depend on how the total convective heating of the atmosphere responds to changing scale. If the total heating remains unchanged, increasing the zonal scale or the vertical scale always leads to a weaker circulation. Conversely, if the total heating grows in proportion to the spatial scale, the circulation becomes stronger with increasing scale. These conclusions are shown to be consistent with a three-dimensional numerical model. Moreover, they are useful in describing the observed seasonal and interannual (ENSO) variability of the Indo-Pacific Walker circulation. On both time scales, the overturning becomes weaker with increasing zonal scale of the convective region, reminiscent of our solutions where we do not vary the total convective heating. Reanalysis data also indicate that the zonal circulation is quite strongly damped, thus yielding a result that the circulation strength is directly proportional to the warm-pool spatial-mean precipitation.
A Modular, Non-Newtonian, Model, Library Framework (DebrisLib)
for Post-Wildfire Flood Risk Management

Abstract. Wildfires increase flow and sediment load through removal of vegetation, alteration of soils, decreasing infiltration, and production of ash commonly generating a wide variety of geophysical flows (i.e., hyperconcentrated flows, mudflows, debris flows, etc.). Numerical modellers have developed a variety of Non-Newtonian algorithms to simulate each of these processes, and therefore, it can be difficult to understand the assumptions and limitations in any given model or replicate work. This diversity in the processes and approach to non-Newtonian simulations makes a modular computation library approach advantageous. A computational library consolidates the algorithms for each process and discriminates between these processes and algorithms with quantitative non-dimensional thresholds. This work presents a flexible numerical library framework (DebrisLib) to simulate large-scale, post-wildfire, non-Newtonian geophysical flows using both kinematic wave and shallow-water models. DebrisLib is derived from a variety of non-Newtonian closure approaches that predict a range of non-Newtonian flow conditions. It is a modular code designed to operate with any Newtonian, shallow-water parent code architecture. This paper presents the non-Newtonian model framework and demonstrates its effectiveness by calling it from two very different modelling frameworks developed by the U.S. Army Corp of Engineers (USACE), specifically, within the one-dimensional and two-dimensional Hydrologic Engineering Centre River Analysis System (HEC-RAS) and two-dimensional Adaptive Hydraulics (AdH) numerical models. The development and linkage-architecture were verified and validated using two non-Newtonian flume experiments selected to represent a range of non-Newtonian flow conditions (i.e., hyperconcentrated flow, mudflow, debris flow) commonly associated with post-wildfire flooding.
Nest camouflage records on five social wasp species (Vespidae, Polistinae) from southeastern Brazil

Social insects use different strategies to defend their colonies, including camouflage. In order to expand knowledge, regarding the strategy of camouflage in social wasps, information is presented on the camouflage pattern of the species: Parachartergus smithii (De Saussure), Parachartergus wagneri Du Buysson, Chartergellus communis Richards, Metapolybia cingulata (Fabricius) and Mischocyttarus anthracinus Richards.These species are uncommon in inventory studies in Brazil. Records occur in different Conservation Units, between 2011 and 2019, in the Minas Gerais State, Brazil Southeastern. Camouflage seems to be the main defense strategy for these species, due to the color and shape of their nests in line with the substrate, as well as their docile behavior. The exception is Metapolybia cingulata, which in addition to camouflage shows aggressive behavior in some situations, which suggests the use of different strategies in the colony defense.
Southern Ocean Heat Storage, Reemergence, and Winter Sea Ice Decline Induced by Summertime Winds

The observational record shows a substantial 40-yr upward trend in summertime westerly winds over the Southern Ocean, as characterized by the southern annular mode (SAM) index. Enhanced summertime westerly winds have been linked to cold summertime sea surface temperature (SST) anomalies. Previous studies have suggested that Ekman transport or upwelling is responsible for this seasonal cooling. Here, another process is presented in which enhanced vertical mixing, driven by summertime wind anomalies, moves heat downward, cooling the sea surface and simultaneously warming the subsurface waters. The anomalously cold SSTs draw heat from the atmosphere into the ocean, leading to increased depth-integrated ocean heat content. The subsurface heat is returned to the surface mixed layer during the autumn and winter as the mixed layer deepens, leading to anomalously warm SSTs and potentially reducing sea ice cover. Observational analyses and numerical experiments support our proposed mechanism, showing that enhanced vertical mixing produces subsurface warming and cools the surface mixed layer. Nevertheless, the dominant driver of surface cooling remains uncertain; the relative importance of advective and mixing contributions to the surface cooling is model dependent. Modeling results suggest that sea ice volume is more sensitive to summertime winds than sea ice extent, implying that enhanced summertime westerly winds may lead to thinner sea ice in the following winter, if not lesser ice extent. Thus, strong summertime winds could precondition the sea ice cover for a rapid retreat in the following melt season.
Forecasting the Returns of Cryptocurrency: A Model Averaging Approach

This paper aims to enrich the understanding and modelling strategies for cryptocurrency markets by investigating major cryptocurrencies’ returns determinants and forecast their returns. To handle model uncertainty when modelling cryptocurrencies, we conduct model selection for an autoregressive distributed lag (ARDL) model using several popular penalized least squares estimators to explain the cryptocurrencies’ returns. We further introduce a novel model averaging approach or the shrinkage Mallows model averaging (SMMA) estimator for forecasting. First, we find that the returns for most cryptocurrencies are sensitive to volatilities from major financial markets. The returns are also prone to the changes in gold prices and the Forex market’s current and lagged information. Then, when forecasting cryptocurrencies’ returns, we further find that an ARDL(p,q) model estimated by the SMMA estimator outperforms the competing estimators and models out-of-sample.
Sensing and Interaction of His-Tagged CA19-9 Antigen with Graphene-Modified Electrodes

The electrochemical oxidation of CA19-9 tagged with L-Histidine (CA199-His) was investigated for the first time with screen-printed electrodes (DS) modified with graphene oxide (DS/GO) or thermally reduced graphene oxide (DS/TRGO). Successive cyclic voltammograms (CV) measurements performed with bare and DS/TRGO electrodes proved that the intensity of the oxidation peak (I peak) is time-dependent. In fact, the oxidation signal increased over time, reached a maximum and then decreased due to the saturation of the surface with CA199-His molecules. The interaction of CA199-His with GO, TRGO, or graphite was additionally studied by isothermal calorimetry, a useful tool for accessing information regarding the biomolecule adsorption on graphene surface. The adsorption of CA199-His on TRGO was generating a higher heat, suggesting quantitative and efficient interactions. At the same time, in the case of TRGO, the saturation was not reached, indicating the existence of more free binding sites than in the case of GO and graphite. As such, the carbohydrate marker CA199-His showed a higher affinity for the TRGO surface than for the graphite or GO surfaces. The lack of saturation in the case of TRGO may indicate a continuous structural modification of the antigen when interacting with the graphene surface.
Conceptualizing Audit Fatigue in the Context of Sustainable Supply Chains

Organizations rely heavily on audits and compliance related activities to prove their competency, credibility, and firm performance. Sustainability audits encompass entire supply chains and are very complex due to, firstly, the global nature of supply chains and, secondly, the expansive scope of sustainability, which may include financial, manufacturing, social, and environmental audits. Adding to this dilemma is the absence of a consensus on standards related to sustainability, resulting in differences, variations, and multiple interpretations. While the frequency, complexity, and scope of audits has increased, unfortunately so has the incident of audit fraud, which has seen increasing media coverage in recent times, often implicating major multinationals and their supply chains. We posit that this trend of increasing audit activity is causing “audit fatigue”, which, in turn, may influence the audit outcome, i.e., either audit fraud or a clean audit. This study proposes that audit fatigue is a genuine issue faced by organizations and needs to be conceptualized.
“Whatever it takes”: first budgetary responses to the COVID-19 pandemic in France

PurposeThis paper highlights the emergency budgetary measures taken by the French government in response to the COVID-19 pandemic health crisis and identifies some of the key political, economic, social and environmental factors and consequences associated with those measures.Design/methodology/approachThe authors conduct a thorough analysis of official reports, bills and academic and news articles related to the pandemic management in France. The authors’ analysis covers the period from January 24 to July 31, 2020.FindingsDespite previous austerity policies, France faced the health crisis with a very high level of debt, which has complicated the management of the COVID-19 crisis. Although significant, the response brought by the French government seems in the end to be rather choppy.Originality/valueThis paper highlights three elements of analysis that allow a better understanding of the budgetary management process in France. The authors first discuss the notion of budgetary flexibility. Then, they show that the growth of participatory budgets in local communities gives hope for a possible and much needed decentralization process implying a stronger commitment of citizens. Finally, they highlight a budgetary paradox; that is, massive funding of polluting industries versus ecological issues. These three elements of analysis all advocate the need for a deeper engagement among different levels of government and actors.
Long‐Term Observations of Galactic Cosmic Ray LET Spectra in Lunar Orbit by LRO/CRaTER

The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) has been orbiting the Moon since 2009 aboard the Lunar Reconnaissance Orbiter (LRO). From this vantage point, it samples the interplanetary energetic particle population outside the shielding of the Earth's magnetosphere. We report the sensor's observations of galactic cosmic rays (GCRs) over a complete solar activity cycle. CRaTER is designed primarily to measure not the spectra of GCR particles outside the sensor but rather their effects on matter, and in particular, it measures the linear energy transfer (LET) or energy‐deposit spectrum in its silicon detectors. We have used the Geant4 radiation‐transport code to devise a background‐rejection algorithm to improve these measurements of LET under 9.9 g/cm2 of shielding, and the resulting observations show the changing radiation effects of GCRs as their intensity and spectrum vary with solar modulation. As of 2020 this intensity, after declining during solar maximum activity, has recovered to a level that exceeds by a few percent the historically high values seen during the deep solar minimum at the start of the LRO mission in 2009.
Absorption spectroscopy of mass‐selected ions in neon matrices

A new approach for the spectroscopic characterization of mass‐selected ions is demonstrated. In this a stream of ions coming from a quadrupole mass selector are codeposited with neon to form a 5 K matrix and the absorption spectrum is measured. The potential of this technique is illustrated by the observation of the electronic absorption spectra of C+2, C2N+2, and C2Cl+2, in turn, after mass selection.
Absolute Measurement of Dynamic Low-Finesse Fabry–Perot Cavity Using Phase-Shifting White-Light Interferometry

When the cavity changes during spectrum acquisition process, Doppler phenomena will occur and cause conventional scanning white-light interferometry (WLI) to fail. To absolutely demodulate the cavity length of the dynamic low-finesse Fabry–Perot sensor, a novel laser frequency modulated phase-shifting WLI (PS-WLI) is proposed. Two phase-shifted spectra can be obtained by introducing a fixed phase-shift after each scanning frequency. The phase results containing modulations of frequency scanning and dynamic signals are retrieved based on quadrature demodulation. Although the full-spectrum acquisition frequency of the proposed PS-WLI is only 50 Hz, 0.5∼20 kHz vibration signals can be demodulated. It combines the advantages of frequency-switched two-step phase shifting interferometry (PSI) and scanning WLI to achieve absolute measurement with high sampling rate. Numerical simulations and experiments verify its effectiveness.
Effect of Laser Peening on the Mechanical Properties of Aluminum Alloys Probed by Synchrotron Radiation and X-Ray Free Electron Laser

Synchrotron radiation (SR) and X-ray free electron laser (XFEL) are indispensable tools not only for the exploration of science but also for the evolution of industry. We used SR and XFEL to elucidate the mechanism and the effects of laser peening without coating (LPwC) which enhances the durability of metallic materials. X-ray diffraction (XRD) employing SR revealed that the residual stress (RS) in the top surface became compressive as the laser pulse irradiation density increased with appropriate overlapping of adjacent laser pulses. SR-based computed tomography (CT) was used to nondestructively reconstruct three-dimensional (3D) images of fatigue cracks in aluminum alloy, revealing that LPwC retarded crack propagation on the surface and inside of the sample. SR-based computed laminography (CL) was applied to friction stir welded (FSWed) aluminum alloy plates to visualize fatigue cracks propagating along the welds. The fatigue crack had complicated shape; however, it became a semi-ellipsoid once projected onto a plane perpendicular to the fatigue loading direction. Ultra-fast XRD using an XFEL was conducted to investigate the dynamic response of aluminum alloy to an impulsive pressure wave simulating the LPwC condition. The diffraction pattern changed from spotty to smooth, implying grain refinement or subgrain formation. Shifts in diffraction angles were also observed, coinciding with the pressure history of laser irradiation. The durations of the dynamic phenomena were less than 1 µs; it may be possible to use high-repetition lasers at frequencies greater than kHz to reduce LPwC processing times.
Preparing Undergraduate Learners with Skills Required by a Transformative Work Environment

Higher Education systems need to undergo significant transformation to produce graduates who are highly skilled and prepared for their roles in the impending workforce. Despite an improvement in university throughput rates, unemployment remains predominantly high, which could be attributed to the misalignment between mandatory workplace skills and those possessed by graduates. The focus of the study was on the exploration of skills acquired from the new General Education modules introduced into the curriculum of undergraduate programmes. Hence, the study discovered learners’ perspectives on the relevance of the skills acquired from these modules in the undergraduate programme to ensure survival in the workforce. The methodology adopted in the study was a quantitative survey research design, using the questionnaire as the data collection tool from a census of the first-year learners registered in the undergraduate programme. The results provided significant evidence to support the view that the skills acquired from the General Education modules in the undergraduate programme are indispensable in industry and enhanced critical thinking of the learners.
Interpretation of Spectroscopic Ellipsometry Data on Protein Layers on Gold Including Substrate-Layer Interactions

Interface effects are often neglected when interpreting ellipsometric data on thin organic films on solid substrates. We find that on gold substrates such effects give rise to spurious absorption seen as a nonzero imaginary part of the optical response function of adsorbed protein layers. With spectroscopic ellipsometry it is revealed that these effects are more pronounced in the visible part of the spectrum than in the ultraviolet part. We conclude that the standard three-phase model (ambient-layer-substrate) in general is insufficient for an accurate analysis of the layer properties. Large errors in the deduced refractive indices, film thicknesses, and surface concentrations may arise. A four-phase model for interpretation of spectroscopic ellipsometric data on protein layers on gold is proposed as an improvement. In this model the interaction between the adsorbed layer and the gold substrate is included and modeled in effective medium approximations. The physical mechanism behind the interaction is suggested to be depletion of electrons from a small zone in the gold substrate, close to its surface. By usingthis new model, a considerable improvement is obtained and the spectra obtained are free from the unphysical absorption in the visible part of the photon energy spectrum. The time development of the interaction between the protein layer and the gold substrate leads to a suggestion of a two-state adsorption model for protein adsorption. The studies in this report are limited to layers of ferritin and albumin, but we think that the results are applicable to other protein layers as well.