bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanistic Studies on the Bismuth‐Catalyzed Transfer Hydrogenation of Azoarenes
Authors: Moon Hye Won , Wang Feng , Bhattacharyya Kalishankar , Planas Oriol , Leutzsch Markus , Nöthling Nils , Auer Alexander A. , Cornella Josep 
Published: September 2023

AbstractOrganobismuth‐catalyzed transfer hydrogenation has recently been disclosed as an example of low‐valent Bi redox catalysis. However, its mechanistic details have remained speculative. Herein, we report experimental and computational studies that provide mechanistic insights into a Bi‐catalyzed transfer hydrogenation of azoarenes using p‐trifluoromethylphenol (4) and pinacolborane (5) as hydrogen sources. A kinetic analysis elucidated the rate orders in all components in the catalytic reaction and determined that 1 a (2,6‐bis[N‐(tert‐butyl)iminomethyl]phenylbismuth) is the resting state. In the transfer hydrogenation of azobenzene using 1 a and 4, an equilibrium between 1 a and 1 a ⋅ [OAr]2 (Ar=p‐CF3−C6H4) is observed, and its thermodynamic parameters are established through variable‐temperature NMR studies. Additionally, pKa‐gated reactivity is observed, validating the proton‐coupled nature of the transformation. The ensuing 1 a ⋅ [OAr]2 is crystallographically characterized, and shown to be rapidly reduced to 1 a in the presence of 5. DFT calculations indicate a rate‐limiting transition state in which the initial N−H bond is formed via concerted proton transfer upon nucleophilic addition of 1 a to a hydrogen‐bonded adduct of azobenzene and 4. These studies guided the discovery of a second‐generation Bi catalyst, the rate‐limiting transition state of which is lower in energy, leading to catalytic transfer hydrogenation at lower catalyst loadings and at cryogenic temperature.
Improved high‐temperature energy storage density at low‐electric field in BOPP/PVDF multilayer films
Authors: Zhang Tiandong , Liang Shuang , Yu Hainan , Zhang Changhai , Tang Chao , Li Hua , Chi Qingguo 
Published: September 2023

AbstractBiaxially oriented polypropylene (BOPP) is the most favorable commercial dielectric energy storage film due to its low dielectric loss and high electric breakdown strength. However, its low dielectric constant always leads to relatively low energy storage density. In this study, we propose an efficient strategy to increase the dielectric constant of BOPP films by laminating with high dielectric polyvinylidene fluoride (PVDF). Utilizing the high dielectric constant of PVDF and optimizing its thickness and layers, the high‐temperature energy storage density at low‐electric field is significantly improved. When the thickness of interlayer PVDF is 5 μm and the total number of stacked layers is 7, the BOPP/PVDF multilayer films deliver excellent high‐temperature energy storage performance. The dielectric constant of BOPP/PVDF multilayer films increases to 3.54, 1.74 times higher than pure BOPP films. At a low electric field of 200 kV/mm, the discharged energy storage density of BOPP/PVDF multilayer films increases to 1.02 and 0.99 J/cm3 at 100 and 125°C. (BOPP ~0.50 and 0.48 J/cm3@200 kV/mm). This work provides an efficient way to improve the high‐temperature energy storage density of BOPP films by constructing all‐organic multilayer structure.
A Late Holocene case study from south‐west France: Combining geomorphology and geophysics to understand archaeological site morphology
Authors: Larcanché Marie , Verdet Cécile , Sirieix Colette , Steinmann Ronan , Colin Sylvain , Mathé Vivien , Chevillot Christian , Matéo Sylvain , Houillon Nicolas , Hantrais Juliette , Hiriart Eneko 
Published: September 2023

AbstractThis article combining geophysics and archaeology aims to provide a more comprehensive characterization of the La Ruchelle valley located in the south of the Celtic site of La Peyrouse (Saint‐Félix‐de‐Villadeix, Dordogne, France) (occupied between the 3rd century BC and the 2nd century AD) through geological prospection (core sampling, geotechnical prospection and mechanical prospection) and near‐surface geophysics (electrical resistivity tomography). On this site, other studies have been carried out since the discovery of the site, such as magnetic prospecting and a hydrogeological study. Geophysical data coupled with geological prospection were used to understand the geology of the valley: (1) The bottom of the valley is filled with colluvium with a thickness of 6 m maximum; (2) part of the colluvium filling characterize by a very low resistivity is indeed archaeological remains; (3) three very distinct geological horizons have been detected—two of these horizons are characteristic of Campanian limestone (C6d and C6e), and the last consists of colluvium with a filling between 2 and 6 m in the centre of the valley, which is particularly thick. This last very thick formation is in fact filled with archaeological and prehistoric remains.
Die elektronische Wechselwirkung als Vorstufe chemischer Reaktionen zwischen Metallen und chemisorbierten Gasen
Authors: Suhrmann R. , Wedler G. 
Published: September 2023

AbstractDie gleichzeitige Untersuchung der Veränderung des elektrischen Widerstandes und der photoelektrischen Empfindlichkeit dünner im Ultra‐Hochvakuum aufgedampfter Metallfilme durch Chemisorption von Gasen läßt auf die Art der Bindung schließen. Danach ähnelt die Bindung zwischen chemisorbierter Molekel und Adsorbens derjenigen einer chemischen Oberflächenverbindung. Während in qualitativer Hinsicht nur geringe Unterschiede bestehen, kann die Stärke der Bindung sehr verschieden sein.Bei der Chemisorption wird Kohlenmonoxyd an Nickel vorwiegend mit der negativen Belegung nach außen gebunden, während gleichzeitig Metallelektronen in Richtung der Molekel stark beansprucht werden. An Kupfer hingegen erfolgt bei tiefen Temperaturen eine Vergrößerung der Elektronenkonzentration zwischen den beiden Partnern, verbunden mit einer starken Verschiebung von Metallelektronen zur Molekel hin und von Molekelelektronen in Richtung des Metalls; an Wismut sind zwei Bindungstypen nebeneinander anzunehmen.Stickstoff wird an Nickel nur bei tiefen Temperaturen chemisorbiert, und zwar in ähnlicher Weise wie CO an Kupfer; die Beanspruchung der Metallelektronen ist jedoch schwacher. An Wolfram erfolgt bei 293°K eine schwache Dissoziation des Stickstoffs, die zu einer Bindung mit der negativen Belegung nach außen führt.Sauerstoff dissoziiert an Nickel und Wolfram auch bei 90°K in Atome, die unter starker Beanspruchung von Metallelektronen mit der negativen Belegung nach außen gebunden sind. Auch an Wismut wirken die Sauerstoff‐Atome als Elektronenakzeptoren; gleichzeitig ist auch die Adsorption von molekularem Sauerstoff zu beobachten, der das Elektronen‐Austrittspotential der Wismut‐Oberfläche herabsetzt.Die Adsorption von Wasserstoff an Wismut ist sehr gering und wahrscheinlich molekular. An den d‐Metallen Nickel und Platin liegen nebeneinander molekularer und atomarer Wasserstoff vor. Der letztere kann als H− chemisorbiert werden oder in Proton und Elektron dissoziieren. Hierbei vermag er in die Film‐Oberfläche einzudringen, bei Platin stärker als bei Nickel.
The Role of Spinel Oxides in the Oxidation of Iron and Its Alloys
Authors: Birchenall C. E. 
Published: September 2023

AbstractAlloying elements in iron may decrease the rate of oxidation by lowering the composition range of wüstite or by eliminating it as a stable phase in the presence of the alloy and spinel phases. Additional protection may be obtained if the alloying element lowers the range of defect concentration in the spinel phase or decreases the ion mobilities. A sufficiently great decrease in mobilities of the cations may lead to anion control of the spinel growth rates. A working hypothesis to be used as a guide to diffusion studies in spinels is presented.
Parabolic Rate Constants and Diffusion Mechanisms in Oxides and Sulfides
Authors: Moore Walter J. 
Published: September 2023

AbstractIt is shown that the Wagner equation, K = \documentclass{article}\pagestyle{empty}\begin{document}$ \int\limits_{a_1 }^{a_2 } D $\end{document} D dlna, relating the parabolic rate constant K and the diffusion coefficient D of radioactive metal is equivalent to the proportionality between reaction rate and affinity, K = D̄A/kT, where D̄ is the average diffusion coefficient in the oxide layer. This is simply the equation postulated by irreversible thermodynamics for a reaction close to equilibrium. In the case of oxides with cationic vacancies, D = D0 P and K = nD0. It is suggested that the experimental data do not suffice to prove the proportionality K/A because the measurements have been restricted to oxygen pressures too far from equilibrium. The results are discussed of new diffusion experiments in the systems A g/Ag2S, Zn/ZnO, O/Cu2O, and possible mechanisms are proposed.
Über die Brauchbarkeit des Fuoss‐Kraus‐Verfahrens und des Additivitäts‐verfahrens nach Kohlrausch zur Auswertung von Leitfähigkeitsmessungen an schwachen Säuren in Wasser‐Methanol‐Mischungen
Authors: Kortüm G. , Wenck H. 
Published: September 2023

AbstractLeitfähigkeiten von o‐Chlorbenzoesäure und Kalium‐o‐chlorbenzoat in Wasser, Methanol und Wasser‐Methanol‐Gemischen wurden gemessen. Die Meßergebnisse wurden nach dem Fuoss‐Kraus‐Verfahren mit und ohne Lösungsmittelkorrektur und nach einem Verfahren auf Grundlage des Additivitätsgesetzes von Kohlrausch ausgewertet. Eine ausführliche Fehlerbetrachtung zeigt die Problematik derartiger Messungen an schwachen Säuren. Das Additivitätsverfahren führt zu richtigeren Ergebnissen. Das Fuoss‐Kraus‐Verfahren ist bei schwachen Elektrolyten in Lösungsmitteln niederer Dielektrizitätskonstante überempfindlich gegen Schwankungen der Meßwerte und Solvenskorrekturen und liefert verzerrte Ergebnisse. Die Solvenskorrektur durch einfachen Abzug der Eigenleitfähigkeit des Lösungsmittels ist nicht ausreichend, weil die Ursachen dieser Leitfähigkeit nicht bekannt sind, und führt deshalb nur zu einer relativen Verbesserung der Ergebnisse.Die bei 1,2,6‐Dinitrophenol bereits beobachtete Konzentrationsabhängigkeit der thermodynamischen Dissoziationskonstanten wurde in geringerem Grade auch bei o‐Chlorbenzoesäure gefunden. Diese Inkonstanz ist wahrscheinlich gleichfalls eine Folge der zu groben Lösungsmittelkorrektur.Die Leitfähigkeit des o‐chlorbenzoesauren Kaliums folgt dem Quadratwurzelgesetz. Die experimentelle Grenzneigung ist in Wasser geringfügig, in Methanol und Wasser‐Methanol‐Gemischen aber beträchtlich geringer als die theoretische nach Debye‐Hückel‐Onsager.
Berechnung der Lösungsentropie des Wasserstoffs in flüssigen Metallen und Nickellegierungen
Authors: Schenck Hermann , Lange Klaus W. 
Published: September 2023

AbstractDie Standardlösungsentropie des Wasserstoffs in flüssigen Metallen und Nickellegierungen wird mittels Modellvorstellungen und der statistischen Thermodynamik absolut berechnet. Für flüssige Lösungen nähert sich die experimentelle Lösungsentropie der theoretischen recht gut an. In ausreichend überhitzten flüssigen Metallen und Metallegierungen sind gelöste Wasserstoffatome anscheinend wie ein Quasigas frei beweglich.
The expression pattern of cytokeratin 6a in epithelial cells of different origin in dermo‐epidermal skin substitutes in vivo
Authors: Michalak‐Micka Katarzyna , Tenini Celina , Böttcher‐Haberzeth Sophie , Mazzone Luca , Pontiggia Luca , Klar Agnes S. , Moehrlen Ueli , Biedermann Thomas 
Published: September 2023

AbstractKeratinocytes are the predominant cell type of skin epidermis. Through the programmed process of differentiation, they form a cornified envelope that provides a physical protective barrier against harmful external environment. Keratins are major structural proteins of keratinocytes that together with actin filaments and microtubules form the cytoskeleton of these cells. In this study, we examined the expression pattern and distribution of cytokeratin 6a (CK6a) in healthy human skin samples of different body locations, in fetal and scar skin samples, as well as in dermo‐epidermal skin substitutes (DESSs). We observed that CK6a expression is significantly upregulated in fetal skin and scar tissue as well as in skin grafts after short‐term transplantation. Importantly, the abundance of CK6a corresponds directly to the expression pattern of wound healing marker CK16. We postulate that CK6a is a useful marker to accurately evaluate the homeostatic state of DESSs.
Automated and continuous assessment implementation in a programming course
Authors: Calderon Kevin , Serrano Nicolás , Blanco Carmen , Gutierrez Iñigo 
Published: September 2023

AbstractContinuous assessment is an assessment methodology whose objective is to assess students on an ongoing basis. However, designing, organizing, correcting, and evaluating continuous assessment increases the workload of teachers. Moreover, this methodology may not promote deep learning if it is not implemented properly. In this study, we implemented continuous assessment in an undergraduate programming subject using an automated assessment tool to reduce the workload of professors. We used design‐based research (DBR) to implement a prototype of assessment methodology which includes an automated assessment tool developed by our research group. DBR provides us with a scientific background for this implementation through an iterative process in which we progressively come to assess all the activities that students perform in the course. In the different iterations of this process, we have collected students' final and project grades, and their opinions through surveys about the assessments we have implemented. These results allow us to demonstrate that the performance of at least two types of students improves after the implementation of continuous assessment, while at the same time, the depth of learning in the class is not affected. We have also found that students are more motivated and committed to the course when continuous assessment is used as they prefer automated assessment over the traditional exercises. In addition, the implementation of the continuous assessment has shown us some unexpected outcomes about flexibility in methodology design, collection of large amounts of data from the learning process, and students acquiring useful skills for programming. In reality, this can result in students gaining deeper knowledge if they are confronted with a greater number of situations during this time in which they test their knowledge.
Initial treatment for FIGO 2018 stage IIIC cervical cancer based on histological type: A 14‐year multicenter study
Authors: Ye Yanna , Zhang Guochao , Li Zhiqiang , Chen Biliang , Zhao Hongwei , Yang Ying , Wang Li , Yao Jilong , Chen Xiaolin , Huang Yahong , Lang Jinghe , Liu Ping , Chen Chunlin 
Published: September 2023

AbstractBackgroundTo compare the oncological outcomes of radical chemotherapy (R‐CT), abdominal radical hysterectomy (ARH), and neoadjuvant chemotherapy and radical surgery (NACT) for International Federation of Gynecology and Obstetrics (FIGO) 2018 stage IIIC cervical cancer, according to histological types: squamous cell carcinoma (SCC) and adenocarcinoma (AC)/adenosquamous cell carcinoma (ASC).MethodsA comparison of 5‐year overall survival (OS) and disease‐free survival (DFS) was performed for the SCC and AC/ASC subgroups for the three initial treatments, assessed using Kaplan–Meier and Cox proportional hazards regression analysis and validated using propensity score matching (PSM).ResultsThe study included 4086 patients: R‐CT, n = 1913; ARH, n = 1529; and NACT, n = 644. AC/ASC had a lower survival rate (63.7%) than SCC (73.6%) and a higher recurrence and mortality rate (36.3% and 26.4%, respectively). The 5‐year OS and DFS rates were different in the SCC group for R‐CT, ARH, and NACT (OS: 69.8% vs. 80.8% vs. 73.0%, p < 0.001; DFS: 66.7% vs. 70.7% vs. 56.4%, p < 0.001), also in the AC/ASC group (OS: 46.1% vs. 70.6% vs. 55.6%, p < 0.001; DFS: 42.7% vs. 64.6% vs. 40.8%, p < 0.001). As for initial treatment, survival outcomes were worse for AC/ASC treated with R‐CT and ARH than for SCC (both p < 0.05), with no group differences between the two treated with NACT.ConclusionInitial treatment influences oncological prognosis for patients with FIGO 2018 stage IIIC cervical cancer. ARH is an alternative treatment for stage IIIC cervical SCC and AC/ASC, and NACT needs to be chosen with caution, moreover, R‐CT for AC/ASC requires careful selection.
Do the importance of influencer‐ and customer‐generated content on social media affect willingness to pay more for potential customers?
Authors: Tuncer İlhami , Kartal Ahmet Selim 
Published: September 2023

AbstractThe number of social media platforms and users have reached significant amounts. Users can interact with millions of other users by sharing their experiences and evaluations concerning the product/service they purchased on social media. This social media sharing can hence affect the purchasing decision processes of potential customers who are searching for information. Moreover, sharing from different sources such as influencers and customers may create differences in the importance the potential consumer attaches to the shared content. Since there is there is a gap in the existing literature, there is a need to explore these relationships. Consequently, we examined the relationship between information quality, willingness to pay more (WPM), source credibility, the importance attached to participant sharing (IPS), and the importance attached to non‐participant sharing (INPS). A questionnaire designed to test this relationship was administered to 323 participants; the obtained data was then analyzed using partial least squares path modeling. According to the analysis results, we noted the emergence of a positive association of information quality with INPS and IPS (posts by both customers and influencers). In contrast, we discovered a relationship of source credibility with INPS (posts by both customers and influencers) and IPS (posts by influencers). In addition, the positive association of INPS (posts by both customers and influencers) and WPM was confirmed. These main findings indicate that e‐commerce companies should persuade and encourage their customers and influencers to post from their profiles.
High‐Resolution X‐ray Absorption and Emission Spectroscopy for Detailed Analysis of New CO2 Methanation Catalysts
Authors: Strübbe Sven , Nowakowski Michal , Schoch Roland , Bauer Matthias 
Published: September 2023

AbstractA new approach for the characterization of CO2 methanation catalysts prepared by thermal decomposition of a nickel MOF by hard X‐ray photon‐in/photon‐out spectroscopy in form of high energy resolution fluorescence detected X‐ray absorption near edge structure spectroscopy (HERFD‐XANES) and valence‐to‐core X‐ray emission (VtC‐XES) is presented. In contrast to conventional X‐ray absorption spectroscopy, the increased resolution of both methods allows a more precise phase determination of the final catalyst, which is influenced by the conditions during MOF decomposition.
Preferred treatment focus among college students with eating disorders and comorbid mental health problems in a digital cognitive‐behavioral guided self‐help program
Authors: D'Adamo Laura , Grammer Anne Claire , Rackoff Gavin N. , Fitzsimmons‐Craft Ellen E. , Lipson Sarah Ketchen , Newman Michelle G. , Taylor C. Barr , Eisenberg Daniel , Wilfley Denise E. 
Published: September 2023

AbstractObjectiveTo examine the mental health problems that college students with eating disorders (EDs) and comorbid depression and/or anxiety disorders preferred to target first in a digital treatment program and explore correlates of preferred treatment focus.MethodsFour hundred and eighty nine college student users of a digital cognitive‐behavioral guided self‐help program targeting common mental health problems (76.7% female, Mage = 20.4 ± 4.4, 64.8% White) screened positive for an ED and ≥one other clinical mental health problem (i.e., depression, generalized anxiety disorder, social phobia, and/or panic disorder). Students also reported on insomnia, post‐traumatic stress, alcohol use, and suicide risk. Before treatment, they indicated the mental health problem that they preferred to target first in treatment. Preferred treatment focus was characterized by diagnostic profile (i.e., ED + Depression, ED + Anxiety, ED + Depression + Anxiety), symptom severity, and demographics.Results58% of students with ED + Anxiety, 47% of those with ED + Depression, and 27% of those with ED + Depression + Anxiety chose to target EDs first. Across diagnostic profiles, those who chose to target EDs first had more severe ED symptoms than those who chose to target anxiety or depression (ps < .05). Among students with ED + Depression + Anxiety, those who chose to target EDs first had lower depression symptoms than those who chose to target depression, lower generalized anxiety than those who chose to target anxiety, and lower suicidality than those who chose to target anxiety or depression (ps < .01).ConclusionsStudents with EDs and comorbid depression and/or anxiety disorders showed variable preferred treatment focus across diagnostic profiles. Research should explore specific symptom presentations associated with preferred treatment focus.Public SignificanceFindings indicate that a sizable percentage of college students with depression/anxiety who also have EDs prefer to target EDs first in treatment, highlighting the importance of increasing availability of ED interventions to college students. Students with EDs and comorbid depression and/or anxiety disorders showed variable preferred treatment focus across diagnostic profiles, and preference to target EDs was associated with greater ED psychopathology across diagnostic profiles.
The unimodal intransitivity–fertility relationship is not mediated by demographic trade‐offs in a subtropical forest
Authors: Huang Zhengliang , Li Yuanzhi , Wang Weitao , Li Buhang , Luo Wenqi , Wang Youshi , Chu Chengjin 
Published: September 2023

AbstractIntransitive competition has long been acknowledged as a potential mechanism favoring species coexistence. However, its prevalence, variance along environmental gradients, and possible underlying mechanisms (trade‐offs) in plant communities (especially in forests) has seldom been examined. A recently developed “reverse‐engineering” approach based on Markov Chain allowed us to estimate the competitive transition matrices and competitive intransitivity from observational abundance data. Using this approach, we estimated competitive intransitivity of five dominant species in a subtropical forest and then related it to soil fertility (soil organic matter and soil pH) and demographic trade‐offs (growth–survival and stature–recruitment trade‐offs). In our forest plot, intransitive competition was common among the dominant species and peaked at the intermediate level of soil organic matter. Neither the growth–survival trade‐off nor the stature–recruitment trade‐off was positively related to competitive intransitivity. Our study for the first time empirically supported the unimodal intransitivity–fertility relationship in forests, which, however, was not mediated by the two demographic trade‐offs in our plot.