bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enantioselektive Synthese von Phosphinoboranen via kristallisationsinduzierter dynamischer Racematspaltung des lithiierten Intermediates durch Verständnis des zugrunde liegenden Epimerisierungsprozesses
Authors: Kuzu Mehmet Yasin , Schmidt Annika , Strohmann Carsten 
Published: March 2024

AbstractHier wird die erfolgreiche kristallisationsinduzierte dynamische Racematspaltung (CIDR) eines α‐lithiierten Phosphinoborans mithilfe des leicht zugänglichen und kostengünstigen chiralen Liganden (R,R)‐TMCDA beschrieben. Ausgehend von dem wichtigen P‐prochiralen Baustein Dimethylphenylphosphinoboran konnten Phosphinoborane in Ausbeuten von bis zu 80 % und Enantiomerenverhältnissen von bis zu 98 : 2 durch Kristallisation des lithiierten Zwischenprodukts erhalten werden. NMR‐basierte Deuterium‐Markierungsexperimente zeigen, dass die Epimerisierung in Lösung auf dem intermolekularen Protonentransfer zwischen dem nicht lithiierten Phosphinoboran und dem entsprechenden lithiierten Zwischenprodukt beruht, sodass die Anwesenheit überschüssigen Eduktes in einem optimierten Lösungsmittelgemisch der Hauptfaktor für eine erfolgreiche enantioselektive Synthese ist. Quantenchemische Berechnungen mit verschiedenen auf Festkörperstrukturen basierenden Modellsystemen bestätigen diese experimentellen Ergebnisse. Durch den Einblick in den Epimerisierungsmechanismus wurden wesentliche Prinzipien für die CIDR von lithiierten Phosphinoboranen aufgeklärt, die auf andere wichtige P‐stereogene Verbindungen und einfache chirale Amine erweitert werden könnten.
Efficient Homolytic Cleavage of H2O2 on Hydroxyl‐Enriched Spinel CuFe2O4 with Dual Lewis Acid Sites
Authors: Tian Lei , Tang Zi‐Jun , Hao Le‐Yang , Dai Ting , Zou Jian‐Ping , Liu Zhao‐Qing 
Published: March 2024

AbstractTraditional H2O2 cleavage mediated by macroscopic electron transfer (MET) not only has low utilization of H2O2, but also sacrifices the stability of catalysts. We present a non‐redox hydroxyl‐enriched spinel (CuFe2O4) catalyst with dual Lewis acid sites to realize the homolytic cleavage of H2O2. The results of systematic experiments, in situ characterizations, and theoretical calculations confirm that tetrahedral Cu sites with optimal Lewis acidity and strong electron delocalization can synergistically elongate the O−O bonds (1.47 Å → 1.87 Å) in collaboration with adjacent bridging hydroxyl (another Lewis acid site). As a result, the free energy of H2O2 homolytic cleavage is decreased (1.28 eV → 0.98 eV). H2O2 can be efficiently split into ⋅OH induced by hydroxyl‐enriched CuFe2O4 without MET, which greatly improves the catalyst stability and the H2O2 utilization (65.2 %, nearly 2 times than traditional catalysts). The system assembled with hydroxyl‐enriched CuFe2O4 and H2O2 affords exceptional performance for organic pollutant elimination. The scale‐up experiment using a continuous flow reactor realizes long‐term stability (up to 600 mL), confirming the tremendous potential of hydroxyl‐enriched CuFe2O4 for practical applications.
Colloidal Zeta Potential Modulation as a Handle to Control the Crystallization Kinetics of Tin Halide Perovskites for Photovoltaic Applications
Authors: Wang Junfang , Huang Junjie , Abdel‐Shakour Muhammad , Liu Tianhua , Wang Xu , Pan Yongle , Wang Lixia , Cui Enhao , Hu Jin‐Song , Yang Shihe , Meng Xiangyue 
Published: March 2024

AbstractTin halide perovskites (THPs) have demonstrated exceptional potential for various applications owing to their low toxicity and excellent optoelectronic properties. However, the crystallization kinetics of THPs are less controllable than its lead counterpart because of the higher Lewis acidity of Sn2+, leading to THP films with poor morphology and rampant defects. Here, a colloidal zeta potential modulation approach is developed to improve the crystallization kinetics of THP films inspired by the classical Derjaguin‐Landau‐Verwey‐Overbeek (DLVO) theory. After adding 3‐aminopyrrolidine dihydro iodate (APDI2) in the precursor solution to change the zeta potential of the pristine colloids, the total interaction potential energy between colloidal particles with APDI2 could be controllably reduced, resulting in a higher coagulation probability and a lower critical nuclei concentration. In situ laser light scattering measurements confirmed the increased nucleation rate of the THP colloids with APDI2. The resulting film with APDI2 shows a pinhole‐free morphology with fewer defects, achieving an impressive efficiency of 15.13 %.
Enantioselective Synthesis of Phosphine Boranes via Crystallization‐Induced Dynamic Resolution of Lithiated Intermediate by Understanding the Underlying Epimerization Process
Authors: Kuzu Mehmet Yasin , Schmidt Annika , Strohmann Carsten 
Published: March 2024

AbstractDescribed herein is the successful crystallization‐induced dynamic resolution (CIDR) of an α‐lithiated phosphine borane utilizing the easily accessible and inexpensive ligand (R,R)‐TMCDA. Starting from the essential P‐prochiral building block dimethyl phenyl phosphine borane we were able to obtain phosphine boranes in yields up to 80 % and e.r. up to 98 : 2 by crystallization of the lithiated intermediate prior to the trapping reaction. NMR‐based deuterium labeling experiments indicate that the epimerization in solution is based on the intermolecular proton transfer between nonlithiated phosphine borane and the corresponding lithiated intermediate, rendering the presence of the remaining starting compound in an optimized solvent mixture the main factor for successful enantioselective synthesis. Quantum chemical calculations using different model systems based on solid state structures confirm these experimental results. By gaining insights into the epimerization mechanism, essential principles for CIDR of lithiated phosphine boranes are elucidated that may be expanded to other important P‐stereogenic compounds and simple chiral amines.
Alkoxycarbonyl Groups in Metalloesters Showing Oxocarbenium‐like Structure and Alkylating Reactivity
Authors: Xu Yingzhuang , Feng Bingjian , Li Songyi , Fang Huayi 
Published: March 2024

AbstractIn contrast to the well‐documented acylating reactivity, the alkylating reactivity of the alkoxycarbonyl group, as signified by its oxocarbenium‐like resonance structure, remains almost unexplored. Herein, the first series of Co/Ni dinuclear metalloesters exhibiting the novel oxocarbenium‐like alkoxycarbonyl groups were synthesized and characterized. In these deformed alkoxycarbonyl groups, the Ccarbonyl−Oalkoxyl bonds were contracted to 1.177(11)~1.191(9) Å with the elongations of the Ccarbonyl=Ocarbonyl bonds to 1.368(13)~1.441(9) Å. Meanwhile, the O−Calkyl bonds were also elongated to 1.522(11) ~1.607(15) Å, and were by far the longest O−Calkyl bonds reported for alkoxycarbonyl groups. As triggered by the long O−Calkyl distances, the alkylating reactivity of the oxocarbenium‐like methoxycarbonyl group towards a series of C/N/O‐nucleophiles via the rare BAL2 mechanism at ambient conditions was examined. Furthermore, the homo‐etherifications of alcohols mediated by the Co/Ni dinuclear metalloesters were investigated. The yields followed the trend ethanol≫n‐propanol≫n‐butanol ≈n‐pentanol, that closely related to the structure features of the alkoxycarbonyl groups in corresponding metalloesters: while the ethoxycarbonyl group showed the reactive oxocarbenium‐like framework, the n‐propoxycarbonyl group displayed the dioxocarbenium‐like skeleton with a shorter O−Calkyl bond; In comparison, the classical frameworks with unactivated alkyl moieties were observed for n‐butoxycarbonyl and n‐pentoxycarbonyl groups.
Dietary low‐fat content supplemented with oxytetracycline impairs physiological functions in Nile tilapia (Oreochromis niloticus) fingerlings
Authors: Limbu Samwel Mchele 
Published: March 2024

AbstractNutrition modulates the vulnerability of animals to xenobiotics insults including antibiotics in cultured fish. However, studies exploring the role of low‐fat diet (LFD) in modulating adverse effects of antibiotics are currently limited. This study explored the physiological effects of feeding LFD supplemented with oxytetracycline (OTC) in Nile tilapia (Oreochromis niloticus) fingerlings. Thirty Nile tilapia (8.64 ± 0.44 g) were tagged and randomly stocked into three tanks and fed on a control diet (CD, 70 g/kg lipid), LFD (20 g/kg lipid) and the LFD supplemented with 2.00 g/kg diet of OTC (80 mg/kg body weight/day), hereafter LFD + OTC for 9 weeks. The results indicated that the Nile tilapia fed on LFD + OTC reduced growth performance and feed utilization efficiency than those fed on CD and LFD. Moreover, the fish fed on LFD + OTC had lower body composition, nutrients digestibility and mesenteric fat index than those fed on CD and LFD. Feeding the fish with LFD + OTC decreased antioxidant capacity in the liver than those fed on CD and LFD. The Nile tilapia fed on LFD + OTC increased hepatotoxicity than those fed on CD and LFD. Feeding the Nile tilapia on LFD + OTC decreased immunity response in the kidney and liver than those fed on CD and LFD. The LFD + OTC affected nutrients metabolism in the liver and serum than other diets. Taken together, feeding LFD with OTC impairs physiological functions of Nile tilapia by inhibiting growth performance, antioxidant capacity, immunity response and nutrient metabolism.
Preventive maintenance for coherent systems considering postponed replacement
Authors: Asadi Majid 
Published: March 2024

AbstractOne primary objective of reliability engineering is to achieve optimal maintenance of technical systems, which ensures they remain in good operating condition. This paper proposes an age‐based preventive optimal maintenance policy for ‐component coherent systems. Under this proposed strategy, the system begins operating at and undergoes preventative maintenance (PM) at a time . If the system fails before , it will be replaced with a new one. If the system is still functioning at time , an assessment is made based on the number of failed components to determine whether the system should be replaced or allowed to continue operating. If the number of failures at is below a predetermined threshold , the PM time is postponed and a new PM time will be scheduled, and the system continues operating in the interval . Otherwise, the entire system is preventively replaced at with a new one. In this scenario, we use a cost function to determine the optimal values of decision variables , , and . To examine the effectiveness of our proposed model, we analyze some examples of coherent systems using graphical and numerical methods.
What are topic emotions? A comparison of children's emotional responses to climate change, climate change learning and climate change picturebooks
Authors: Oberman Rowan 
Published: March 2024

AbstractPekrun and his colleagues highlight the significance and diversity of emotion in education. Their analysis suggests that these emotions can be categorised by their stimuli into those related to the classroom: activities, outcomes, relationships, topics and knowledge processes (epistemic). Most research in this area has focused on achievement emotions, with relatively limited research exploring topic emotions. This paper develops a framework for conceptualising topic emotions. It reports on a design‐based study that captured children's expressions of emotion in response to a climate change education programme using picturebooks. The data brought together emotional responses to climate change, to learning about climate change and to climate‐related picturebooks. Qualitative analysis of these responses highlights how they differ not only with regard to the emotions expressed, but also the structure of the emotional experience. Emotional responses to the broad topic of climate change were expressed as ongoing analytical judgements, where those related to learning about climate change were immersive and finite. Reading climate‐related picturebooks involved exploring how emotion is communicated and evoked. This supported quasi‐emotional experiences, where the reader imagines the emotions of the characters. The picturebooks are also shown to create vicarious emotional experiences, involving ethical‐based responses to the behaviour and circumstances depicted. Based on this analysis, the paper proposes a framework for disaggregating these differing emotional experiences related to topic.
New insights on social finance research in the sustainable development context
Authors: Gonzalez‐Ruiz Juan David , Marín‐Rodríguez Nini Johana , Weber Olaf 
Published: March 2024

AbstractResearch on sustainable finance has experienced significant growth in recent years, but the exploration from a comprehensive perspective is still in its nascent stages. As of July 2023, our research revealed that this area remains relatively underexplored in the existing body of knowledge, leading to a notable lack of comprehensive research analyzing the current state‐of‐the‐art in the social finance arena. To address this gap, our study takes a pioneering approach by utilizing scientometrics and network analysis techniques, specifically employing VOSviewer and Bibliometrix in conjunction with Web of Science and Scopus databases. By merging data from both sources and removing duplicate entries, we established a consolidated database of 401 relevant studies. Through our analysis, we have identified prominent authors, sources, and the most influential studies in the social finance arena. Additionally, we examined the coupling of studies and authors to ascertain their significance in this emerging domain. The results have unveiled several prominent further research, including mainly social banking, Islamic finance, social innovation, the impact of the COVID‐19 pandemic, impact investing, social impact bonds, and Sustainable Development Goals. By shedding light on the current landscape, our findings comprehensively understand the field's progress and potential directions. This insight is valuable for market participants, researchers, policymakers, and decision‐makers seeking to navigate and contribute to the evolving landscape of sustainable finance with a social focus. Furthermore, our innovative use of scientometrics and network analysis sets a precedent for future research exploring the complex interplay between finance, development, and sustainability.
Examples and tutorials on using Google Colab and Gradio to create online interactive student‐learning modules
Authors: Ferreira Ricardo , Canesche Michael , Jamieson Peter , Neto Omar P. Vilela , Nacif Jose A. M. 
Published: March 2024

AbstractThis work provides online learning modules and instructions on how educators can leverage these technologies to help students learn in a personalized online environment. In particular, we focus on Google Colab, and the features provided by the Gradio Python library to provide interactivity within these modules. The contributions of this work include: (1) Development of a teaching framework using Gradio/Colab that offers automated grading and feedback for both educators and students; (2) Design of a versatile proposal, accommodating beginners with a straightforward interface while addressing the needs of advanced learners; (3) Creation of a comprehensive set of examples tailored for teaching digital logic subjects, with adaptability for application in various computer science areas. (4) A classification of these example learning modules in terms of their learning level for the students; (5) A novel client‐server approach based on Colab/Gradio, allowing teachers to manage the main notebook efficiently while providing a lightweight and reliable interface for students. The goal of this work is to further expose educators to the remarkable capabilities that cloud computing brings to online supplemental education, noting that large language models such as ChatGPT complement this work, in that chatbots will be able to guide students in these dynamic simulations.
Fullertubes inhibit mycobacterial viability and prevent biofilm formation by disrupting the cell wall
Authors: Shenoy Varun , Gunda Rashmika , Noble Cora , Haraguchi Annalisa , Stevenson Steven , Daniel Jaiyanth 
Published: March 2024

AbstractMycobacterium tuberculosis and nontuberculous mycobacteria such as Mycobacterium abscessus cause diseases that are becoming increasingly difficult to treat due to emerging antibiotic resistance. The development of new antimicrobial molecules is vital for combating these pathogens. Carbon nanomaterials (CNMs) are a class of carbon‐containing nanoparticles with promising antimicrobial effects. Fullertubes (C90) are novel carbon allotropes with a structure unique among CNMs. The effects of fullertubes on any living cell have not been studied. In this study, we demonstrate that pristine fullertube dispersions show antimicrobial effects on Mycobacterium smegmatis and M. abscessus. Using scanning electron microscopy, light microscopy, and molecular probes, we investigated the effects of these CNMs on mycobacterial cell viability, cellular integrity, and biofilm formation. C90 fullertubes at 1 µM inhibited mycobacterial viability by 97%. Scanning electron microscopy revealed that the cell wall structure of M. smegmatis and M. abscessus was severely damaged within 24 h of exposure to fullertubes. Additionally, exposure to fullertubes nearly abrogated the acid‐fast staining property of M. smegmatis. Using SYTO‐9 and propidium iodide, we show that exposure to the novel fullertubes compromises the integrity of the mycobacterial cell. We also show that the permeability of the mycobacterial cell wall was increased after exposure to fullertubes from our assays utilizing the molecular probe dichlorofluorescein and ethidium bromide transport. C90 fullertubes at 0.37 µM and C60 fullerenes at 0.56 µM inhibited pellicle biofilm formation by 70% and 90%, respectively. This is the first report on the antimycobacterial activities of fullertubes and fullerenes.
Introducing Weakly Ligated Tris(trifluoromethyl)copper(III)
Authors: Motornov Vladimir , Procházka Martin , Alpuente Nora , Salvador Pedro , Slavíček Petr , Klepetářová Blanka , Ribas Xavi , Beier Petr 
Published: March 2024

AbstractTris(trifluoromethyl)copper(III), Cu(CF3)3, was prepared for the first time and fully characterized in the form of weakly coordinated highly reactive solvent neutral adducts (DMF)2Cu(CF3)3 and (MeCN)Cu(CF3)3. Free Cu(CF3)3 is an elusive molecule of distorted T‐shaped geometry with Lewis acid properties, which is stabilized by solvation. Substitution of solvent molecules with monoanionic ligands in mild conditions afforded the first Cu(III)(CF3)3 carboxylates [Cu(CF3)3(OAc)]− and [Cu(CF3)3(OBz)]− and Cu(III) nitrito complex [Cu(CF3)3(ONO)]−. An improved synthesis of valuable Grushin's trifluoromethylation reagents via the intermediacy of (MeCN)Cu(CF3)3 was developed. (DMF)2Cu(CF3)3 demonstrated promising properties in photoinduced radical C‐H trifluoromethylation. Oxidation state theoretical studies showed the Cu(CF3)3 compounds to be borderline between classical Cu(III) and inverted ligand field Cu(I) assignment.
Interseeded cover crops in wide‐row corn: An opportunity for northern cropping systems
Authors: Goettl Brady , Andersen Bryce , DeSutter Thomas , Franzen David , Wick Abbey 
Published: March 2024

AbstractCover crops are an effective way to reduce soil erosion and promote soil health. However, in North Dakota and other northern climates where corn (Zea mays L.) is an important commodity crop, killing frosts generally occur before harvest, leaving little opportunity for cover crop planting. By interseeding cover crops into corn during the growing season, the cover crops are given a longer period to establish. The purpose of this study was to identify the impact cover crops interseeded into wide‐row (60‐inch) corn have on soil water content and corn productivity. Two experimental sites were established in 2020 near Leonard and Rutland, ND. Both sites were organized into randomized complete block designs, with three cover crop treatments in Leonard (n = 9) and four cover crop treatments in Rutland (n = 16). Cover crops were no‐till drilled into the corn at the V4 growth stage. The cover crop treatments were diverse mixes developed to either provide pollinator habitat, overwinter, or winter‐kill. Throughout the growing season, soil gravimetric water content and cover crop biomass was monitored. At the end of the growing season, dry cover crop biomass ranged from 189 to 1445 lb ac−1. The presence and type of interseeded cover crops did not have a statistically significant effect on soil water content or corn yield. It is suspected the above average precipitation during the month of July led to adequate amounts of soil water for the entirety of the cover crop growing season, limiting the difference between treatments.
Pd(0)‐Catalyzed Asymmetric Intramolecular Grignard‐Type Reaction of Vinyl Iodide‐Carbonyl
Authors: Dong Ming , Tong Xiaofeng 
Published: March 2024

AbstractThe insertion of carbonyl into C(sp2)−Pd(II) σ‐bond (Grignard‐type addition) was not established until the 1990s. While this elemental reaction has been well explored since then, its application in Pd(0) asymmetric catalysis remain elusive. Herein, we report the Pd(0)‐catalyzed asymmetric intramolecular Grignard‐type reaction of vinyl iodide‐carbonyl in the presence of HCO2H additive, affording cyclic allylic alcohol with good to excellent enantioselectivity and diastereoselectivity. Mechanistic studies suggested that besides serving as an efficient reductant, HCO2H is also capable of facilitating protonation of the involved secondary alkoxyl‐Pd(II), thus completely suppressing the β‐H elimination. Moreover, no KIE was found in the competing reaction between vinyl iodide‐aldehyde and 1‐deuterated one, demonstrating the facile step of aldehyde insertion.
Phenanthrothiophene‐Triazine Star‐Shaped Discotic Liquid Crystals: Synthesis, Self‐Assembly, and Stimuli‐Responsive Fluorescence Properties
Authors: Zeng Chong‐Yang , Deng Wen‐Jing , Zhao Ke‐Qing , Redshaw Carl , Donnio Bertrand 
Published: March 2024

AbstractLipophilic biphenylthiophene‐ and phenanthrothiophene‐triazine compounds, BPTTn and CPTTn, respectively, were prepared by a tandem procedure involving successive Suzuki‐Miyaura coupling and Scholl cyclodehydrogenation reactions. These compounds display photoluminescence in solution and in thin film state, solvatochromism with increasing solvent's polarity, as well as acidochromism and metal ion recognition stimuli‐responsive fluorescence. Protonation of BPTT10 and CPTT10 by trifluoroacetic acid results in fluorescence quenching, which is reversibly restored once treated with triethylamine (ON‐OFF switch). DFT computational studies show that intramolecular charge transfer (ICT) phenomena occurs for both molecules, and reveal that protonation enhances the electron‐withdrawing ability of the triazine core and reduces the band gap. This acidochromic behavior was applied to a prototype fluorescent anti‐counterfeiting device. They also specifically recognize Fe3+ through coordination, and the recognition mechanism is closely related to the photoinduced electron transfer between Fe3+ and BPTT10/CPTT10. CPTTn self‐assemble into columnar rectangular (Colrec) mesophase, which can be modulated by oleic acid via the formation of a hydrogen‐bonded supramolecular liquid crystal hexagonal Colhex mesophase. Finally, CPTTn also form organic gels in alkanes at low critical gel concentration (3.0 mg/mL). Therefore, these star‐shaped triazine molecules possess many interesting features and thus hold great promises for information processing, liquid crystal semiconductors and organogelators.