bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spatially‐Resolved Insights Into Local Activity and Structure of Ni‐Based CO2 Methanation Catalysts in Fixed‐Bed Reactors
Authors: Serrer Marc‐André , Stehle Matthias , Schulte Mariam L. , Besser Heino , Pfleging Wilhelm , Saraҫi Erisa , Grunwaldt Jan‐Dierk 
Published: May 2021

AbstractOn a Ni/Al2O3 and a Ni−Fe/Al2O3 catalyst spatial concentration and temperature profiles were determined that occur along the axial direction of the catalyst bed. They were correlated to structural gradients under reaction conditions to elucidate the local dependency of catalyst structure on reaction‐induced changes of the gas phase. The quantitative concentration and temperature profiles revealed a hotspot in the first third part of the fixed‐bed, which led to by‐product formation of CO. Complementary structural information obtained by spatially‐resolved quick X‐ray absorption spectroscopy unraveled a strong impact of reaction‐induced gradients in gas phase on the oxidation state of Fe with a higher oxidation state towards the end of the catalyst bed, while Ni was only slightly affected. Diffuse reflectance infrared Fourier transform spectroscopy further revealed that addition of Fe to a Ni/Al2O3 catalyst reduces the amount of adsorbed CO species. Hence, Fe hampers blocking of active Ni0 sites by CO and preserves a high fraction of reduced Ni species. Furthermore, an alternative reaction pathway observed on Ni−Fe provided locally a higher activity for CO2 hydrogenation. Overall, the importance of considering local gradients in catalytic reactors is demonstrated.
Reversible Vapochromic Luminescence Accompanied by Planar Half‐Chair Conformational Change of a Propeller‐Shaped Boron β‐Diketiminate Complex
Authors: Ito Shunichiro , Yaegashi Misao , Tanaka Kazuo , Chujo Yoshiki 
Published: May 2021

AbstractLeakage of volatile organic compounds (VOCs) is one of the most severe industrial problems, because it can cause environmental pollution, global warming, fire, and explosion. Hence, the visualization of leakage is an essential technology to detect it at an early stage. Molecular crystals, fluorescence color of which can be changed by the exposure to VOCs could potentially serve as the sensing materials for realizing rapid and facile VOC detection. However, these materials usually require harsh conditions, such as heating or a vacuum, to recover their initial phases for reuse. Therefore, it remains a challenge to obtain completely reversible sensing systems without such energy‐consuming recycling processes. Herein, the reversible color change of fluorescence from the crystals of a propeller‐shaped boron β‐diketiminate complex is reported. The complex was crystallized in distinct crystalline phases having different luminescent colors. Importantly, these phases were interconverted very rapidly (time constant <60 s) and repeatedly upon exposure to the vapors of the appropriate VOCs. The small energy differences between conformers of the complex could lead to this pseudopolymorphic behavior. This finding could be applied for the development of further eco‐friendly reversible sensing materials based on four‐coordinated boron complexes.
E4 Transfer (E=P, As) to Ni Complexes
Authors: Heinl Veronika , Schmidt Monika , Eckhardt Maria , Eberl Miriam , Seitz Andreas E. , Balázs Gábor , Seidl Michael , Scheer Manfred 
Published: May 2021

AbstractThe use of [Cp′′2Zr(η1:1‐E4)] (E=P (1 a), As (1 b), Cp′′=1,3‐di‐tert‐butyl‐cyclopentadienyl) as phosphorus or arsenic source, respectively, gives access to novel stable polypnictogen transition metal complexes at ambient temperatures. The reaction of 1 a/1 b with [CpRNiBr]2 (CpR=CpBn (1,2,3,4,5‐pentabenzyl‐cyclopentadienyl), Cp′′′ (1,2,4‐tri‐tert‐butyl‐cyclopentadienyl)) was studied, to yield novel complexes depending on steric effects and stoichiometric ratios. Besides the transfer of the complete En unit, a degradation as well as aggregation can be observed. Thus, the prismane derivatives [(Cp′′′Ni)2(μ,η3:3‐E4)] (2 a (E=P); 2 b (E=As)) or the arsenic containing cubane [(Cp′′′Ni)3(μ3‐As)(As4)] (5) are formed. Furthermore, the bromine bridged cubanes of the type [(CpRNi)3{Ni(μ‐Br)}(μ3‐E)4]2 (CpR=Cp′′′: 6 a (E=P), 6 b (E=As), CpR=CpBn: 8 a (E=P), 8 b (E=As)) can be isolated. Here, a stepwise transfer of En units is possible, with a cyclo‐E42− ligand being introduced and unprecedented triple‐decker compounds of the type [{(CpRNi)3Ni(μ3‐E)4}2(μ,η4:4‐E′4)] (CpR=CpBn, Cp′′′; E/E′=P, As) are obtained.
Teaching‐learning laboratory “makeScience!” and students’ interest – Studies on the learning environment “Donor‐Acceptor Reactions – placed in Bubble Tea Balls”
Authors: Syskowski Sabrina , Kunina‐Habenicht Olga , Ducci Matthias , Wagner Ingo 
Published: May 2021

AbstractDie Lernumgebung „Donator‐Akzeptor‐Reaktionen – platziert in Bubble‐Tea‐Bällchen“ wurde im Rahmen des Verbundprojekts MINT2KA für Schüler:innen der gymnasialen Oberstufe entwickelt. Ihre Erprobung erfolgte in den Lehr‐Lern‐Laboren der Pädagogischen Hochschulen Karlsruhe und Heidelberg. Im Mittelpunkt der wissenschaftlichen Begleitung stand die Perspektive der Schüler:innen bezüglich ihrer Wahrnehmungen beim Besuch der Lehr‐Lern‐Labore. Im Speziellen wurde das situationale Interesse, die soziale Eingebundenheit und die Selbsttätigkeit von Schüler:innen untersucht. Dabei wurde das gezeigte Interesse als mehrdimensionales Konstrukt verstanden und die Beziehung der Schüler:innen zur Erfahrung während der Lernumgebung als zentrales Element gesehen. Im Rahmen der Untersuchungen wurde der Grad des situationalen Interesses durch die subjektiv empfundene Wertschätzung, das emotionale Erleben, die wertbezogene Valenz und die epistemische Orientierung einer Person in Bezug auf den Laborbesuch erfasst. Die Resultate der Fragebogenstudie ergaben positive Werte hinsichtlich der Subdimensionen des situationalen Interesses. Darüber hinaus konnte eine hohe Selbsttätigkeit der Schüler:innen sowie eine soziale Eingebundenheit durch die evozierte lernförderliche Atmosphäre festgestellt werden.
A new adjusted Liu estimator for the Poisson regression model
Authors: Amin Muhammad , Akram Muhammad Nauman , Kibria B. M. Golam 
Published: May 2021

SummaryThe Poisson regression model (PRM) is usually applied in the situations when the dependent variable is in the form of count data. For estimating the unknown parameters of the PRM, maximum likelihood estimator (MLE) is commonly used. However, its performance is suspected when the regressors are multicollinear. The performance of MLE is not satisfactory in the presence of multicollinearity. To mitigate this problem, different biased estimators are discussed in the literature, that is, ridge and Liu. However, the drawback of using the traditional Liu estimator is that in most of the times, the shrinkage parameterd, attains a negative value which is the major disadvantage of traditional Liu estimator. So, to overcome this problem, we propose a new adjusted Poisson Liu estimator (APLE) for the PRM which is the robust solution to the problem of multicollinear explanatory variables. For assessment purpose, we perform a theoretical comparison with other competitive estimators. In addition, a Monte Carlo simulation study is conducted to show the superiority of the new estimator. At the end, two real life applications are also considered. From the findings of simulation study and two empirical applications, it is observed that the APLE is the most robust and consistent estimation method as compared to the MLE and other competitive estimators.
Enhanced Conversion Efficiency Enabled by Species Migration in Direct Solar Energy Storage
Authors: Lin Guanzhou , Almakrami Husain , Emran Huzaifa , Ruthen Amar , Hu Jie , Wei Zi , Liu Fuqiang 
Published: May 2021

AbstractSolar energy can be stored via either an indirect route in which electricity is involved as an intermediate step, or a direct route that utilizes photogenerated charge carriers for direct solar energy conversion. In this study, we investigate the fundamental difference between the direct and indirect routes in solar energy conversion using a new photoelectrochemical energy storage cell (PESC) as a model device. This PESC centers on a liquid junction that utilizes CH3NH3PbI3 perovskite to drive photoelectrochemical reactions of Benzoquinone (BQ) and Ferrocene (Fc) redox species. The experimental studies show that the equilibrium redox potentials are 0.1 V and −0.78 V (vs Ag/AgNO3) for Fc+/Fc and BQ/BQ.−, respectively, which would produce a theoretical open‐circuit voltage of 0.88 V for the storage device. The physics‐based computational analysis shows a relatively flat reaction rate distribution in the electrode for the indirect route; however, in the direct route the photoelectrochemical reaction rate is critically affected by electron concentration due to strong light absorption of the perovskite material, which has been shown to vary by at least 10‐fold in the transverse direction across the photoelectrode. The drastic variation of reaction rate in the photoelectrode creates an electric field that is 7.5 times stronger than the bulk electrolyte, which causes the photo‐converted reaction product (i. e., BQ.−) to drift away from the photoelectrode thereby creating a constant reaction driving force. As a result, it has been shown that the intrinsic solar to chemical conversion (ISTC) efficiency improves by ∼40 % for the direct route compared to the indirect route at 0.05 mA/cm2.
Green patenting and corporate social responsibility: Does family involvement in business matter?
Authors: Aiello Francesco , Cardamone Paola , Mannarino Lidia , Pupo Valeria 
Published: May 2021

AbstractThis paper explores whether family and non‐family firms differ in terms of their capability to introduce green patenting. By considering the environmental performance as a corporate social responsibility related concern, the analysis is based on a large data set of patenting activities carried out by Italian manufacturing firms over the period 2009–2017. Results show that family firms are less likely than non‐family firms to implement innovations in green technologies. This holds true whatever the level of accumulation in green and non‐green knowledge.
Recontextualisation and the teaching of subjects
Authors: Hordern Jim 
Published: May 2021

AbstractThis paper interrogates the concept of recontextualisation and discusses its relevance for understandings of the knowledge required for teaching subjects. While various distinctive approaches to recontextualisation can be identified, this analysis primarily draws on the work of Bernstein, with recontextualisation discussed in the broader context of work on the sociology of educational knowledge. It is argued that Bernstein's approach to recontextualisation can be usefully extended by absorbing insights derived from recent work conceptualising expertise and practice, through a reconsideration of disciplinarity, and by reflecting on historical studies of the transformation of specialised practical knowledge. It is suggested that recontextualisation can help us better understand (i) the structure of subjects and their relationship to disciplines and (ii) the relationship between knowledge and ‘content’ in the process of curriculum making. Recontextualisation is nevertheless problematic without an acknowledgement of the role of teachers in shaping and enacting recontextualisation principles and navigating recontextualisation rules.
Noninvasively measured immune responses reflect current parasite infections in a wild carnivore and are linked to longevity
Authors: Ferreira Susana C. M. , Veiga Miguel M. , Hofer Heribert , East Marion L. , Czirják Gábor Á. 
Published: May 2021

AbstractHost immune defenses are important components of host–parasite interactions that affect the outcome of infection and may have fitness consequences for hosts when increased allocation of resources to immune responses undermines other essential life processes. Research on host–parasite interactions in large free‐ranging wild mammals is currently hampered by a lack of verified noninvasive assays. We successfully adapted existing assays to measure innate and adaptive immune responses produced by the gastrointestinal mucosa in spotted hyena (Crocuta crocuta) feces, including enzyme‐linked immunosorbent assays (ELISAs), to quantify fecal immunoglobulins (total IgA, total IgG) and total fecal O‐linked oligosaccharides (mucin). We investigated the effect of infection load by an energetically costly hookworm (Ancylostoma), parasite richness, host age, sex, year of sampling, and clan membership on immune responses and asked whether high investment in immune responses during early life affects longevity in individually known spotted hyenas in the Serengeti National Park, Tanzania. Fecal concentrations of IgA, IgG, and mucin increased with Ancylostoma egg load and were higher in juveniles than in adults. Females had higher mucin concentrations than males. Juvenile females had higher IgG concentrations than juvenile males, whereas adult females had lower IgG concentrations than adult males. High IgA concentrations during the first year of life were linked to reduced longevity after controlling for age at sampling and Ancylostoma egg load. Our study demonstrates that the use of noninvasive methods can increase knowledge on the complex relationship between gastrointestinal parasites and host local immune responses in wild large mammals and reveal fitness‐relevant effects of these responses.
Heart failure related to adult congenital heart disease: prevalence, outcome and risk factors
Authors: Arnaert Stijn , De Meester Pieter , Troost Els , Droogne Walter , Van Aelst Lucas , Van Cleemput Johan , Voros Gabor , Gewillig Marc , Cools Bjorn , Moons Philip , Rega Filip , Meyns Bart , Zhang Zhenyu , Budts Werner , Van De Bruaene Alexander 
Published: May 2021

AbstractAimsInformation on the prevalence, outcome and factors associated with heart failure in patients with adult congenital heart disease (CHD) (ACHD‐HF) is lacking. We aimed at assessing the prevalence and outcome of ACHD‐HF, the variables associated with ACHD‐HF, and the differences between major anatomical/pathophysiological ACHD subgroups.Methods and resultsWe included 3905 patients (age 35.4 ± 13.2 years) under active follow‐up in our institution (last visit >2010). Outcome of ACHD‐HF cases was compared with sex‐ and age‐matched cases. Univariable and multivariable binary logistic regression with ACHD‐HF diagnosis as a dependent variable was performed. Overall prevalence of ACHD‐HF was 6.4% (mean age 49.5 ± 16.7 years), but was higher in patients with cyanotic CHD (41%), Fontan circulation (30%), and a systemic right ventricle (25%). All‐cause mortality was higher in ACHD‐HF cases when compared with controls (mortality rate ratio 4.67 (2.36–9.27); P = 0.0001). In multivariable logistic regression analysis, age at latest follow‐up [per 10 years; odds ratio (OR) 1.52; 95% confidence interval (CI) 1.31–1.77], infective endocarditis (OR 4.11; 95%CI 1.80–9.38), history of atrial arrhythmia (OR 3.52; 95%CI 2.17–5.74), pacemaker implantation (OR 2.66; 95% CI 1.50–4.72), end‐organ dysfunction (OR 2.41; 95% CI 1.03–5.63), New York Heart Association class (OR 9.28; 95% CI 6.04–14.25), heart rate (per 10 bpm; OR 1.27; 95% CI 1.08–1.50), ventricular dysfunction (OR 3.62; 95% CI 2.54–5.17), and pulmonary hypertension severity (OR 1.66; 95% CI 1.21–2.30) were independently related to the presence of ACHD‐HF. Some variables (age, atrial arrhythmia, pacemaker, New York Heart Association, and ventricular dysfunction) were related to ACHD‐HF in all anatomical/physiological subgroups, whereas others were not.ConclusionsACHD‐HF is prevalent especially in complex CHD and is associated with poor prognosis. Our data provide insight in the factors related to ACHD‐HF including differences between specific anatomical and physiological subgroups.
Advanced isolated light chain amyloid cardiomyopathy with negative immunofixation and normal free light chain ratio
Authors: Zach David , Ablasser Klemens , Kolesnik Ewald , Hoeller Viktoria , Fruhwald Friedrich , Prüller Florian , Reiter Clemens , Beham‐Schmid Christine , Lipp Rainer , Rainer Peter P. , Zirlik Andreas , Wölfler Albert , Verheyen Nicolas 
Published: May 2021

AbstractAmyloid light chain (AL) cardiomyopathy is the most malignant specific cardiomyopathy. According to international recommendations, it should be ruled out non‐invasively using the serum free light chain (FLC) ratio and immunofixation electrophoresis in both serum and urine. Here, we report on a 69‐year‐old female patient with new‐onset heart failure with mid‐range ejection fraction. Cardiac imaging was highly suggestive of cardiac amyloidosis. Amyloid scintigraphy showed faint myocardial tracer uptake according to Perugini Score 1, but immunofixation was negative and the FLC ratio was normal, despite a slight increase in lambda FLCs. Endomyocardial biopsy revealed advanced myocardial lambda immunoglobulin light chain deposition. Clinically relevant extracardiac amyloid organ infiltration could not be detected. Conclusively, non‐invasive testing can in rare cases fail to exclude isolated AL amyloid cardiomyopathy. We suggest that even slight increases in serum lambda or kappa FLCs should be considered abnormal in suspected cardiac amyloidosis if non‐invasive testing delivers discrepant results.
Titanium Tetrachloride‐Mediated Approach to Access 2‐Chloro‐2‐Substituted Isoindolin‐1‐ones through the Addition of Alkynes to Acyliminium ions
Authors: Xu Wen‐Ke , Guo Jia‐Ming , Chen Zhao‐Dan , Si Chang‐Mei , Wei Bang‐Guo 
Published: May 2021

AbstractAn asymmetric approach to access 2‐substituted isoindolin‐1‐ones 9–11 was developed through TiCl4‐mediated addition‐chlorination of N,O‐acetals 7 a–7 c with terminal alkynes 8. A range of substrates were amenable to this transformation, and the desired substituted isoindolin‐1‐ones were obtained in moderate to good yields with moderate diastereoselectivities.
Perceptions of a sexual advance from gay men leads to negative affect and compensatory acts of masculinity
Authors: Schermerhorn Nathaniel E. C. , Vescio Theresa K. 
Published: May 2021

AbstractPrior research highlights the relationship between anti‐gay prejudice and masculinity: straight men (1) avoid being misclassified as gay and (2) experience increased anti‐gay attitudes when their masculinity is threatened. We hypothesized that a sexual advance from a gay man would constitute a threat to straight man's masculinity. Four experiments and a cross‐cultural replication (N = 1407) manipulated perceptions of a same‐sex sexual advance and found that straight men experienced greater public discomfort and subsequent anger. This anger predicted both non‐aggressive (e.g., avoidance) and aggressive (e.g., likelihood to use violence) compensatory acts of masculinity. These findings were not ameliorated by reasserting heterosexuality (Study 2), were unique to sexual advances by gay men, not straight women (Study 3), and were replicated in the United States (Study 4a) and the United Kingdom (Study 4b). Findings suggest that a same‐sex sexual advance threatens straight men's masculinity and implications for future research are discussed.
Optimization of wavy fin‐and‐elliptical tube heat exchanger using CFD, multi‐objective genetic algorithm and radical basis function
Authors: Yu Chao , Xue Xiangyao , Shi Kui , Wang Renhao , Zhang Lei , Shao Mingzhen 
Published: May 2021

AbstractThis article presents an accurate and efficient optimization method for heat exchanger. The structure of the original heat exchanger was optimized by combining LHS sampling, CFD simulation, radical basis function, and multi‐objective optimization. Since the Colburn factor j and the friction factor f are a pair of conflicting goals, so the multi‐objective optimization is adopted. The optimization results showed that the Colburn factor j increased by 5.43% and the friction factor f decreased by 23.31%, indicating that the optimized structure had higher heat transfer efficiency and lower resistance performance. The heat transfer mechanism and optimization effect of heat exchanger are explained by using the field synergy principle, which provides a theoretical basis for the structural design optimization of heat exchanger.
Robust joint resource allocation algorithm for hierarchical underwater acoustic communication networks based on outage probability minimization
Authors: Li Xinbin , Zhao Haihong , Han Song , Wang Binghan , Liu Zhixin 
Published: May 2021

AbstractThis study investigates a joint resource allocation (channel selection (CS) and power allocation (PA)) problem with multiple channels, users, constraints, and uncertainties in the underwater acoustic communication networks (UACNs). A hierarchical joint resource allocation model is formulated considering different user requirements. This model aims to minimize the maximum outage probability of lower users while satisfying the outage requirements of upper users. This study presents a robust distributed power allocation (RDPA) algorithm to solve complex PA problems with nonconvex mixed integers and uncertainties in UACNs. The residual energy of nodes is considered in the proposed RDPA algorithm to balance their energy, thereby extending the working time of the entire network. The proposed robust CS algorithm considers the actual and potential interferences of all neighboring nodes to decrease the interferences of nodes and the entire network, thereby reducing the outage probability of the network. Simulation results are presented to demonstrate the effectiveness of the proposed algorithm.
Forecasting carbon price using a multi‐objective least squares support vector machine with mixture kernels
Authors: Zhu Bangzhu , Ye Shunxin , Wang Ping , Chevallier Julien , Wei Yi‐Ming 
Published: May 2021

AbstractFor improving forecasting accuracy and trading performance, this paper proposes a new multi‐objective least squares support vector machine with mixture kernels to forecast asset prices. First, a mixture kernel function is introduced into taking full use of global and local kernel functions, which is adaptively determined following a data‐driven procedure. Second, a multi‐objective fitness function is proposed by incorporating level forecasting and trading performance, and particle swarm optimization is used to synchronously search the optimal model selections of least squares support vector machine with mixture kernels. Taking CO2 assets as examples, the results obtained show that compared with the popular models, the proposed model can achieve higher forecasting accuracy and higher trading performance. The advantages of the mixture kernel function and the multi‐objective fitness function can improve the forecasting ability of the asset price. The findings also show that the models with a high‐level forecasting accuracy cannot always have a high trading performance of asset price forecasting. In contrast, high directional forecasting usually means a high trading performance.