► Gold particles deposited in vacuum as energy reference for insulating samples in XPS. ► Separation of La 3d and MNN peaks in XP spectra acquired with Al Kα radiation. ► We describe the spectral ...differences between lanthanum oxide and lanthanum hydroxide. ► A doublet in O 1s of La
2O
3 is ascribed to two distinct oxygen sites in the crystal.
A technique is described for deposition of gold nanoparticles under vacuum, enabling consistent energy referencing of X-ray photoelectron spectra obtained from lanthanum hydroxide La(OH)
3 and
in situ treated lanthanum oxide La
2O
3 powders. A method is also presented for the separation of the overlapping lanthanum 3d and MNN peaks in X-ray photoelectron spectra acquired with Al Kα radiation. The lower satellite intensity in La(OH)
3 compared to La
2O
3 is related to the higher ionicity of the La–O bond in the former compared to the latter compound. The presence of an additional peak in the valence band spectrum of the hydroxide compared to the oxide is attributed to the O–H bond as indicated by density functional theory based calculations. A doublet in the O 1s peak of lanthanum oxide is associated to the presence of two distinct oxygen sites in the crystal structure of this compound.
Species occurrence records from online databases are an indispensable resource in ecological, biogeographical and palaeontological research. However, issues with data quality, especially incorrect ...geo‐referencing or dating, can diminish their usefulness. Manual cleaning is time‐consuming, error prone, difficult to reproduce and limited to known geographical areas and taxonomic groups, making it impractical for datasets with thousands or millions of records.
Here, we present CoordinateCleaner, an r‐package to scan datasets of species occurrence records for geo‐referencing and dating imprecisions and data entry errors in a standardized and reproducible way. CoordinateCleaner is tailored to problems common in biological and palaeontological databases and can handle datasets with millions of records. The software includes (a) functions to flag potentially problematic coordinate records based on geographical gazetteers, (b) a global database of 9,691 geo‐referenced biodiversity institutions to identify records that are likely from horticulture or captivity, (c) novel algorithms to identify datasets with rasterized data, conversion errors and strong decimal rounding and (d) spatio‐temporal tests for fossils.
We describe the individual functions available in CoordinateCleaner and demonstrate them on more than 90 million occurrences of flowering plants from the Global Biodiversity Information Facility (GBIF) and 19,000 fossil occurrences from the Palaeobiology Database (PBDB). We find that in GBIF more than 3.4 million records (3.7%) are potentially problematic and that 179 of the tested contributing datasets (18.5%) might be biased by rasterized coordinates. In PBDB, 1205 records (6.3%) are potentially problematic.
All cleaning functions and the biodiversity institution database are open‐source and available within the CoordinateCleaner r‐package.
This current research consists of two studies that employ the psychological construct of self-referencing with the goal being to identify an optimal means by which ad viewers are able to generate ...mental simulation through advertising. In Study 1 we identify that the ad, when incorporating a self-referencing cue, enables consumers to easily generate mental simulation resulting in marginally greater purchase intention than that generated by the same ad but without the self-referencing cue. We also find that there is a significant moderating role of prior direct product experience on the relationship between self-referencing and mental simulation, but not on that between self-referencing and purchase intention. In Study 2 we confirm the superiority of dynamic self-referencing to static self-referencing from diverse consumer evaluation perspectives to reveal the underlying mechanism that explains the serial mediating role of arousal and mental simulation in generating intention to purchase. More findings and implications are discussed in the discussion section.
•Message framing effects in promoting food waste reduction in events was investigated.•Regulatory focus and reference points can jointly influence persuasiveness.•Prevention focus match with ...self-referencing lead to optimal persuasiveness.•Promotion focus match with other-referencing lead to optimal persuasiveness.•Both online and field experiment studies have confirmed the proposed joint effect.
This research aims to examine the optimal communication strategies to persuade event attendees to engage in food waste reduction (FWR) practices by utilizing the concepts of regulatory focus and reference points in advertising message framing. An online experiment study was conducted to investigate the interaction effects between regulatory focus (prevention- or promotion-focus) and reference points (self- or other-referencing) on consumers’ perceived intrinsic motives of event organizations’ green activities, their attitude toward the company’s FWR practices, and their behavioral intention toward participating in the company’s FWR practices as well as mediating effect of perceived intrinsic motives. Findings revealed a significant interaction effect between regulatory focus and reference points on persuasiveness of green appeals in the context of FWR practices. Mediation analysis revealed that the impact of regulatory focus message on behavioral intention is serially mediated via perceived intrinsic motives and attitude and this serial mediation effects vary in different reference points. Theoretical and managerial implications are discussed.
With more than 9000 papers published annually, X-ray photoelectron spectroscopy (XPS) is an indispensable technique in modern surface and materials science for the determination of chemical bonding. ...The accuracy of chemical-state determination relies, however, on a trustworthy calibration of the binding energy (BE) scale, which is a nontrivial task due to the lack of an internal BE reference. One approach, proposed in the early days of XPS, employs the C 1s spectra of an adventitious carbon layer, which is present on all surfaces exposed to air. Despite accumulating criticism, pointing to the unknown origin and composition of the adventitious carbon, this is by far the most commonly used method today for all types of samples, not necessarily electrically insulating. Alarmingly, as revealed by our survey of recent XPS literature, the calibration procedure based on the C 1s peak of adventitious carbon is highly arbitrary, which results in incorrect spectral interpretation, contradictory results, and generates a large spread in reported BE values for elements even present in the same chemical state. The purpose of this review is to critically evaluate the status quo of XPS with a historical perspective, provide the technique's operating principles, resolve myths associated with C 1s referencing, and offer a comprehensive account of recent findings. Owing to the huge volume of XPS literature produced each year, the consequences of improper referencing are dramatic. Our intention is to promote awareness within a growing XPS community as to the problems reported over the last six decades and present a guide with best practice for using the C 1s BE referencing method.
X‐ray photoelectron spectroscopy (XPS) is an indispensable technique in modern materials science for the determination of chemical bonding as evidenced by more than 10 000 XPS papers published ...annually. A literature survey reveals that in the vast majority of cases an incorrect referencing of the binding energy scale is used, neglecting warnings that have been formulated from the early days of the technique. Consequences for the data reliability are disastrous and decades of XPS work require revisiting. The purpose of this Viewpoint is to highlight the existing problems, review the criticism and suggest ways forward.
X‐ray photoelectron spectroscopy (XPS) is an indispensable technique in modern materials science. A literature survey reveals that in the vast majority of cases an incorrect referencing of the binding energy scale is used, neglecting warnings that have been formulated from the early days of the technique. The purpose of this Viewpoint is to highlight the existing problems and suggest ways forward.
Social media influencers are increasingly recognized for their ability to influence tourists' decision-making processes. The emergent phenomenon of virtual influencers presents an unprecedented ...challenge to their human counterparts, reshaping the dynamics of the tourism industry. It remains a challenge to integrate various forms of destination advertising and harmonize the approaches of both human and virtual influencers to effectively attract tourists. This study addresses this gap by investigating the effectiveness of human and virtual influencers in endorsing natural versus cultural destinations. Adopting source credibility theory, we conduct five empirical studies. Our findings reveal that virtual influencers boost visit intentions for cultural destinations, while human influencers do so for natural destinations. Credibility and self-referencing play a serially mediating role in this process. Furthermore, this study explores the moderating role of tourists’ preference for uniqueness. This research offers valuable insights for tourism industry managers aiming to harness the power of virtual influencers effectively.
Femtosecond light pulses carrying optical angular momentums (OAMs), possessing intriguing properties of helical phase fronts and ultrafast temporal profiles, enable many applications in nonlinear ...optics, strong‐field physics, and laser micromachining. While generation of OAM‐carrying ultrafast pulses and their interactions with matters are intensively studied in experiments, 3D characterization of ultrafast OAM‐carrying light beams in spatiotemporal domain has, however, proved difficult to achieve. Conventional measurement schemes rely on the use of a reference pulsed light beam, which needs to be well characterized in its phase front and to have sufficient overlap and coherence with the beam under test, largely limiting practical applications of these schemes. Here a self‐referencing set‐up is demonstrated based on a tilted interferometer that can be used to measure complete spatiotemporal information of OAM‐carrying femtosecond pulses with different topological charges. Through scanning one interferometer arm, the spectral phase over the pulse spatial profile can be obtained using the tilted interference signal, and the temporal envelope of the light field at one particular position around its phase singularity can be retrieved simultaneously, enabling 3D beam reconstruction. This self‐referencing technique, capable of measuring spatiotemporal ultrafast optical‐vortex beams, may find many applications in fields of nonlinear optics and light–matter interactions.
Ultrafast optical‐vortex beams are of importance in many experiments, while 3D reconstruction of such beams has proved difficult to achieve. Here a novel tilted total electrical‐field reconstruction using a Michelson interferometer temporal scan (TERMITES) technique is reported, which can realize self‐referenced spatiotemporal characterization of ultrafast vortex pulses, providing a powerful tool for studying light–matter interactions.
We report measurements of energy-dependent photoionization delays between the two outermost valence shells of N_{2}O and H_{2}O. The combination of single-shot signal referencing with the use of ...different metal foils to filter the attosecond pulse train enables us to extract delays from congested spectra. Remarkably large delays up to 160 as are observed in N_{2}O, whereas the delays in H_{2}O are all smaller than 50 as in the photon-energy range of 20-40 eV. These results are interpreted by developing a theory of molecular photoionization delays. The long delays measured in N_{2}O are shown to reflect the population of molecular shape resonances that trap the photoelectron for a duration of up to ∼110 as. The unstructured continua of H_{2}O result in much smaller delays at the same photon energies. Our experimental and theoretical methods make the study of molecular attosecond photoionization dynamics accessible.
The C1s signal from ubiquitous carbon contamination on samples forming during air exposure, so called adventitious carbon (AdC) layers, is the most common binding energy (BE) reference in X-ray ...photoelectron spectroscopy studies. We demonstrate here, by using a series of transition-metal nitride films with different AdC coverage, that the BE of the C1s peak E B F varies by as much as 1.44eV. This is a factor of 10 more than the typical resolvable difference between two chemical states of the same element, which makes BE referencing against the C1s peak highly unreliable. Surprisingly, we find that C1s shifts correlate to changes in sample work function S A , such that the sum E B F + S A is constant at 289.50±0.15eV, irrespective of materials system and air exposure time, indicating vacuum level alignment. This discovery allows for significantly better accuracy of chemical state determination than offered by the conventional methods. Our findings are not specific to nitrides and likely apply to all systems in which charge transfer at the AdC/substrate interface is negligible.
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