bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facile Fabrication of a Continuous ZIF‐67 Membrane for Efficient Azeotropic Organic Solvent Mixture Separation
Authors: Sun Hao , Wang Fengkai , Li Xiaoting , Caro Jürgen , Meng Hong , Wang Naixin , An Quan‐Fu 
Published: February 2023

AbstractAzeotropic organic solvent mixture separation is common in the chemical industry but extremely difficult. Zeolitic imidazolate framework‐67 (ZIF‐67) shows great potential in organic solvent mixture separation due to its rigid micropores and excellent stability. However, due to the fast nucleation rate, it is a great challenge to prepare continuous ZIF‐67 membrane layers with ultrathin thickness. In this study, a hydroxy salt layer with high inducible activity was synthesized as a precursor on different porous substrates to prepare ZIF‐67 membranes at room temperature. The precursor layer enables an intact ZIF‐67 membrane with an ultrathin thickness of 176±12 nm. The experimental and simulation results confirmed that the size sieving through the pore windows and the preferential adsorption of polar solvent molecules provide the ZIF‐67 membrane an unprecedented separation performance such as high separation factors and fluxes, for four types of azeotropic organic solvent mixtures.
Experimental Determination of an Isolated trans‐Dinitrosyl Manganese(II) Heme Analogue
Authors: Cao Hongli , Ding Wei , Li Jianfeng 
Published: February 2023

AbstractThe lack of direct proof in either natural or synthetic systems for trans‐dinitrosyl hemes, a key intermediate in the reactions of heme proteins (e.g. soluble guanylate cyclase (sGC), cytochrome c′ and So H‐NOX) with nitric oxide (NO), has hampered understanding of the exact reaction mechanisms, such as the formation of the five‐coordinate heme complex with NO at the proximal side (5c NOP). Herein, we report the first isolation of a dinitrosyl metalloporphyrin complex, the six‐coordinate, low‐spin {Mn(NO)2}7 species [Mn(TPP)(NO)2] (TPP2−=meso‐tetraphenylporphyrin dianion). The complex shows distinct features, such as an elongated axial bond (1.877(9) vs. 1.641(5) Å), a higher NO stretching bond position (1760 vs. 1735 cm−1) and an isotropic resonance at g = 2.0, in sharp contrast to those of five‐coordinate mononitrosyl analogues. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFT) and EPR studies provided deep insight into the reaction processes, demonstrating different responses of porphyrinates to NO.
Modular Metal‐Quinone Networks with Tunable Architecture and Functionality
Authors: Zhong Qi‐Zhi , Richardson Joseph J. , Tian Yuan , Tian Haijiang , Cui Jiwei , Mann Stephen , Caruso Frank 
Published: February 2023

AbstractNanostructured materials with tunable structures and functionality are of interest in diverse areas. Herein, metal ions are coordinated with quinones through metal‐acetylacetone coordination bonds to generate a class of structurally tunable, universally adhesive, hydrophilic, and pH‐degradable materials. A library of metal‐quinone networks (MQNs) is produced from five model quinone ligands paired with nine metal ions, leading to the assembly of particles, tubes, capsules, and films. Importantly, MQNs show bidirectional pH‐responsive disassembly in acidic and alkaline solutions, where the quinone ligands mediate the disassembly kinetics, enabling temporal and spatial control over the release of multiple components using multilayered MQNs. Leveraging this tunable release and the inherent medicinal properties of quinones, MQN prodrugs with a high drug loading (>89 wt %) are engineered using doxorubicin for anti‐cancer therapy and shikonin for the inhibition of the main protease in the SARS‐CoV‐2 virus.
Ligand Assisted Thermal Atomization of Palladium Clusters: An Inspiring Approach for the Rational Design of Atomically Dispersed Metal Catalysts
Authors: Wang Sicong , Ding Tao , Liu Tong , Zhu Yanan , Tao Zhinan , Pang Beibei , Liu Xiaokang , Luo Qiquan , Sun Mei , Sheng Hongting , Zhu Manzhou , Yao Tao 
Published: February 2023

AbstractThe transformation from metal nanocluster catalysts to metal single‐atom catalysts is an important procedure in the rational design of atomically dispersed metal catalysts (ADCs). However, the conversion methods often involve high annealing temperature as well as reducing atmosphere. Herein, we reported a continuous and convenient approach to transfer Pd nanocluster into Pd single‐atom in a ligand assisted annealing procedure, by which means we reduced its activating temperature low to 400 °C. Using ex‐situ microscopy and spectroscopy, we comprehensively monitored the structural evolution of Pd species though the whole atomization process. Theoretical calculation revealed that the structural instability caused by remaining Cl ligands was the main reason for this low‐temperature transformation. The present atomization strategy and mechanistic knowledge for the conversion from cluster to atomic dispersion provides guidelines for the rational design of ADCs.
Elucidation of the Alternating Copolymerization Mechanism of Epoxides or Aziridines with Cyclic Anhydrides in the Presence of Halide Salts
Authors: Xu Jiaxi , Zhang Pengfei , Yuan Youyou , Hadjichristidis Nikos 
Published: February 2023

AbstractOrganic halide salts in combination with metal or organic compound are the most common and essential catalysts in ring‐opening copolymerizations (ROCOP). However, the role of organic halide salts was neglected. Here, we have uncovered the complex behavior of organic halides in ROCOP of epoxides or aziridine with cyclic anhydride. Coordination of the chain‐ends to cations, electron‐withdrawing effect, leaving ability of halide atoms, chain‐end basicity/nucleophilicity, and terminal steric hindrance cause three types of side reactions: single‐site transesterification, substitution, and elimination. Understanding the complex functions of organic halide salts in ROCOP led us to develop highly active and selective aminocyclopropenium chlorides as catalysts/initiators. Adjustable H‐bonding interactions of aminocyclopropenium with propagating anions and epoxides create chain‐end coordination process that generate highly reactive carboxylate and highly selective alkoxide chain‐ends.
NH4+ Deprotonation at Interfaces Induced Reversible H3O+/NH4+ Co‐insertion/Extraction
Authors: Huang Meng , He Qiu , Wang Junjun , Liu Xiong , Xiong Fangyu , Liu Yu , Guo Ruiting , Zhao Yan , Yang Jinlong , Mai Liqiang 
Published: February 2023

AbstractIon insertions always involve electrode‐electrolyte interface process, desolvation for instance, which determines the electrochemical kinetics. However, it′s still a challenge to achieve fast ion insertion and investigate ion transformation at interface. Herein, the interface deprotonation of NH4+ and the introduced dissociation of H2O molecules to provide sufficient H3O+ to insert into materials′ structure for fast energy storages are revealed. Lewis acidic ion‐NH4+ can, on one hand provide H3O+ itself via deprotonation, and on the other hand hydrolyze with H2O molecules to produce H3O+. In situ attenuated total reflection‐Fourier transform infrared ray method probed the interface accumulation and deprotonation of NH4+, and density functional theory calculations manifested that NH4+ tend to thermodynamically adsorb on the surface of monoclinic VO2, and deprotonate to provide H3O+. In addition, the inserted NH4+ has a positive effect for stabilizing the VO2(B) structure. Therefore, high specific capacity (>300 mAh g−1) and fast ionic insertion/extraction (<20 s) can be realized in VO2(B) anode. This interface derivation proposes a new path for designing proton ion insertion/extraction in mild electrolyte.
Plasmonic Cu Nanoparticles for the Low‐temperature Photo‐driven Water‐gas Shift Reaction
Authors: Zhao Jiaqi , Bai Ya , Li Zhenhua , Liu Jinjia , Wang Wei , Wang Pu , Yang Bei , Shi Run , Waterhouse Geoffrey I. N. , Wen Xiao‐Dong , Dai Qing , Zhang Tierui 
Published: February 2023

AbstractThe activation of water molecules in thermal catalysis typically requires high temperatures, representing an obstacle to catalyst development for the low‐temperature water‐gas shift reaction (WGSR). Plasmonic photocatalysis allows activation of water at low temperatures through the generation of light‐induced hot electrons. Herein, we report a layered double hydroxide‐derived copper catalyst (LD‐Cu) with outstanding performance for the low‐temperature photo‐driven WGSR. LD‐Cu offered a lower activation energy for WGSR to H2 under UV/Vis irradiation (1.4 W cm−2) compared to under dark conditions. Detailed experimental studies revealed that highly dispersed Cu nanoparticles created an abundance of hot electrons during light absorption, which promoted *H2O dissociation and *H combination via a carboxyl pathway, leading to the efficient production of H2. Results demonstrate the benefits of exploiting plasmonic phenomena in the development of photo‐driven low‐temperature WGSR catalysts.
Developing functional epoxy/graphene composites using facile in‐situ mechanochemical approach
Authors: Meng Qingshi , Feng Yuanyuan , Han Sensen , Yang Fei , Demiral Murat , Meng Fanze , Araby Sherif 
Published: February 2023

AbstractThe awareness of developing eco‐friendly polymer composites via green chemistry attract much attention in the recent years. In the current work, we explore preparing functional epoxy/ graphene nanocomposites using mechanochemical approach. Graphene platelets (GnPs) were modified with long‐chain surfactant via high‐energy ball milling. Modified‐GnPs (m‐GnPs) promote the dispersion quality and interface strength with epoxy matrix leading to higher mechanical properties, and better electrical and thermal conductivity compared to unmodified GnPs system. At 2.0 vol% m‐GnPs, elastic modulus, tensile strength, and thermal conductivity of epoxy were improved by 889%, 163%, and 105%, respectively. In addition, percolation threshold of electrical conductivity was observed at 0.71 vol% m‐GnPs. Halpin‐Tsai micromechanical model was able to predict the elastic modulus of the epoxy/GnP nanocomposites. The model results were compared experimental measurements. Furthermore, the measurements showed epoxy/m‐GnP film possess high sensitivity to mechanical strains and impact loads. The current work gives a step forward to use mechanochemistry approach in the production of functional epoxy/graphene composites.
Synthesis of molecularly imprinted polymer based on cooperative imprinting for enrichment of gallic acid in Puer tea
Authors: Zhang Li‐Ping , Zhu Fu‐Hua , Guo Yu , Yang Hui , Wang Lan , He Yi‐Fan , Li Shu‐Jing , Li Tian 
Published: February 2023

AbstractThe molecularly imprinted polymer (MIP) for gallic acid (GA) was prepared based on the cooperative imprinting of boronate affinity interactions and hydrogen bond. The fabricated MIP were designed by the polymerization of template with co‐functional monomer, 3‐acrylamidophenylboronic acid (AAPBA) and methacrylic acid (MAA). The characteristics of the resulting polymer (AAPBA‐co‐MAA MIP) were tested by scanning electron microscope (SEM), Fourier transform infrared spectra (FTIR) and nitrogen adsorption–desorption. Bonding performance demonstrated that the AAPBA‐co‐MAA MIP possessed the excellent recognition ability in the incubation solution with pH 7.4 and presented higher adsorption capacity, faster adsorption rate and satisfactory selectivity for GA. Additionally, the AAPBA‐co‐MAA MIP revealed the good applications in the separation and enrichment of GA from Puer tea, and the amount of GA enriched by them was determined to be 2.75 mg g−1. This work suggested that the integration of cooperative imprinting strategy between covalent and non‐covalent would be an effective way to improve the specific recognition performance of the MIP.
Mask or Enhance: Data Curation Aiding the Discovery of Piezoresponse Force Microscopy Contributors
Authors: Ligonde Gardy Kevin , Williams Kerisha N. , Gaponenko Iaroslav , Bassiri‐Gharb Nazanin 
Published: February 2023

AbstractPiezoresponse force microscopy (PFM) is routinely used to probe the nanoscale electromechanical response of ferroelectric and piezoelectric materials. However, many challenges remain in the interpretation of the recovered signal. Specifically, many non‐ferroelectric contributions affect the measured response, ranging from electrostatics, to charge injection and trapping, and topographic cross‐talk. Recently, machine learning (ML) has been utilized to identify multiple contributors within complex data systems, such as PFM response. A substantial advancement in ML approaches for PFM techniques is offered by dimensional stacking, enabling encoding of physical and/or chemical correlations within the materials' response across different data dimensions spanning varying ranges. However, dimensional stacking requires appropriate scaling for each dimension (before ML analysis) to minimize undesired information loss. Here, the impact of clustering globally and locally scaled parameters in polarization switching experiments via resonant PFM (RPFM) are discussed. Specifically, dimensional stacking of scaled parameters can mask or enhance ferroelectric and non‐ferroelectric behaviors, and aid identification of various physical phenomena contributing to the measured RPFM response. This study highlights the importance of data curation for ML, and its role in identifying signal contributors to scanning probe microscopy (SPM)‐based techniques with multidimensional data, such as resonant and/or spectroscopic SPM.
Solid‐state NMR Spectroscopy of Iodine(I) Complexes
Authors: Ward Jas S. , Sievänen Elina I. , Rissanen Kari 
Published: February 2023

AbstractSolid‐state NMR has been applied to a series of Barluenga‐type iodine(I) [L‐I‐L]PF6 (L=pyridine, 4‐ethylpyridine, 4‐dimethylaminopyridine, isoquinoline) complexes as their hexafluorophosphate salts, as well as their respective non‐liquid ligands (L), their precursor silver(I) complexes, and the respective N‐methylated pyridinium and quinolinium hexafluorophoshate salts. These results are compared and contrasted to the corresponding solution studies and single‐crystal X‐ray structures. As the first study of its kind on the solid‐state NMR behavior of halogen(I) complexes, practical considerations are also discussed to encourage wider utilization of this technique in the future.
Nickel(II) Complexes of Tripodal Ligands as Catalysts for Fixation of Atmospheric CO2 as Organic Carbonates
Authors: Muthuramalingam Sethuraman , Velusamy Marappan , Singh Rajput Swati , Alam Mehboob , Mayilmurugan Ramasamy 
Published: February 2023

AbstractThe fixation of atmospheric CO2 into value‐added products is a promising methodology. A series of novel nickel(II) complexes of the type [Ni(L)(CH3CN)2](BPh4)2 1–5, where L=N,N‐bis(2‐pyridylmethyl)‐N′, N′‐dimethylpropane‐1,3‐diamine (L1), N,N‐dimethyl‐N′‐(2‐(pyridin‐2‐yl)ethyl)‐N′‐(pyridin‐2‐ylmethyl) propane‐1,3‐diamine (L2), N,N‐bis((4‐methoxy‐3,5‐dimethylpyridin‐2‐ylmethyl)‐N′,N′‐dimethylpropane‐1,3‐diamine (L3), N‐(2‐(dimethylamino) benzyl)‐N′,N′‐dimethyl‐N‐(pyridin‐2‐ylmethyl) propane‐1,3‐diamine (L4) and N,N‐bis(2‐(dimethylamino)benzyl)‐N′, N′‐dimethylpropane‐1,3‐diamine (L5) have been synthesized and characterized as the catalysts for the conversion of atmospheric CO2 into organic cyclic carbonates. The single‐crystal X‐ray structure of 2 was determined and exhibited distorted octahedral coordination geometry with cis‐α configuration. The complexes have been used as a catalyst for converting CO2 and epoxides into five‐membered cyclic carbonates under 1 atmospheric (atm) pressure at room temperature in the presence of Bu4NBr. The catalyst containing electron‐releasing −Me and ‐OMe groups afforded the maximum yield of cyclic carbonates, 34% (TON, 680) under 1 atm air. It was drastically enhanced to 89% (TON, 1780) under pure CO2 gas at 1 atm. It is the highest catalytic efficiency known for CO2 fixation using nickel‐based catalysts at room temperature and 1 atm pressure. The electronic and steric factors of the ligands strongly influence the catalytic efficiency. Furthermore, all the catalysts can convert a wide range of epoxides (ten examples) into corresponding cyclic carbonate with excellent selectivity (>99%) under this mild condition.
A New Motif in Halogen Bonding: Cooperative Intermolecular S−Br⋅⋅⋅O, O⋅⋅⋅F, and F⋅⋅⋅F Associations in the Crystal Packing of α,ω‐Di(sulfonyl bromide) Perfluoroalkanes
Authors: Wacha Max , Helm David L. , Smart Megan M. , McMillen Colin D. , Casabianca Leah B. , Sachdeva Rakesh , Urick Catherine R. , Wilson London P. , Thrasher Joseph S. 
Published: February 2023

AbstractWe recently reported the first examples of S−Cl⋅⋅⋅O halogen bonding complemented by short F⋅⋅⋅F contacts between neighboring chains that resulted in stabilized crystals of ClSO2(CF2)4SO2Cl and ClSO2(CF2)6SO2Cl. More recently, other researchers studied our crystallographic data further using an Independent Gradient Model (IGM), and they suggested if one goes beyond IUPAC's proposed ‘less than the sum of the van der Waals radii’ criterion that even more noncovalent interactions between fluorine atoms on neighboring chains as well as Cl⋅⋅⋅Cl, Cl⋅⋅⋅S, O⋅⋅⋅F, and O⋅⋅⋅S attractive interactions can be found. With that said, we have prepared samples of the related BrSO2(CF2)nSO2Br derivatives (where n=4, 6, 8, and others), which give rise to even stronger S−Br⋅⋅⋅O halogen bonding interactions complemented minimally by O⋅⋅⋅F and F⋅⋅⋅F intermolecular interactions as shown by X‐ray crystallography and computational chemistry using IGM isosurface plots. Additional spectroscopic characterization (multinuclear NMR, FT‐IR, and MS) of the disulfonyl bromide derivatives BrSO2(CF2)4SO2Br, BrSO2(CF2)6SO2Br, and BrSO2(CF2)8SO2Br has also been obtained as well as some preliminary spectroscopic evidence for BrSO2(CF2)2SO2Br and BrSO2CF2O(CF2)2OCF2SO2Br. The implication of these results toward the preparation of the corresponding disulfonyl iodides is discussed.
The importance of school culture in supporting student mental health in secondary schools. Insights from a qualitative study
Authors: Barker Rhiannon , Hartwell Greg , Egan Matt , Lock Karen 
Published: February 2023

AbstractSchools have the potential to provide a place of education and sanctuary for children and young people of all backgrounds. The rise in mental health problems in children and young people in the wake of the COVID‐19 pandemic, particularly in relation to growing inequities, means that identifying ways in which schools can help respond to this growing mental health crisis demands urgent attention. This paper reports on case studies carried out in two London comprehensive schools, exploring how aspects of school culture impact (both positively and negatively) on student mental health. Methods comprised in‐depth interviews with school staff and parents, focus groups with students and documentary analysis of relevant materials. Fieldwork was conducted during spring 2021 as schools were returning to face‐to‐face learning following national periods of lockdown. Our study shows how schools might attempt to drive positive mental health outcomes through aspects of school culture and uses a system framework to explore complexities around cause and effect in this area. Key findings include the considerable differences in school mental health provision, challenges in the identification of student mental health needs and the importance of recognising how the mental health of teachers must be considered alongside that of students. Overall, we highlight particular dilemmas of the post‐lockdown era that our findings indicate for the education sector, and suggest there may be value in reframing the apparent conflict between ‘attainment gaps’ and personal development, moving towards an educational approach with greater complementarity of these aims.
Spatial correlated incidence modeling with zero inflation
Authors: Wang Feifei , Li Haofeng , Wang Han , Li Yang 
Published: February 2023

AbstractDisease mapping models have been popularly used to model disease incidence with spatial correlation. In disease mapping models, zero inflation is an important issue, which often occurs in disease incidence datasets with high proportions of zero disease count. It is originated from limited survey coverage or unadvanced testing equipment, which makes some regions have no observed patients. Then excessive zeros recorded in the disease incidence dataset would mess up the true distributions of disease incidence and lead to inaccurate estimates. To address this issue, a zero‐inflated disease mapping model is developed in this work. In this model, a zero‐inflated process using Bernoulli indicators is assumed to characterize whether the zero inflation occurs for each region. For regions without zero inflation, a coherent and generative disease mapping model is applied for mapping the spatially correlated disease incidence. Independent spatial random effects are incorporated in both processes to account for the spatial patterns of zero inflation and disease incidence. External covariates are also considered in both processes to better explain the disease count data. To estimate the model, a Markov chain Monte Carlo algorithm is proposed. We evaluate model performance via a variety of simulation experiments. Finally, a Lyme disease dataset of Virginia is analyzed to illustrate the application of the proposed model.
Phases of methodological research in biostatistics—Building the evidence base for new methods
Authors: Heinze Georg , Boulesteix Anne‐Laure , Kammer Michael , Morris Tim P. , White Ian R. ,   the Simulation Panel of the STRATOS initiative
Published: February 2023

AbstractAlthough new biostatistical methods are published at a very high rate, many of these developments are not trustworthy enough to be adopted by the scientific community. We propose a framework to think about how a piece of methodological work contributes to the evidence base for a method. Similar to the well‐known phases of clinical research in drug development, we propose to define four phases of methodological research. These four phases cover (I) proposing a new methodological idea while providing, for example, logical reasoning or proofs, (II) providing empirical evidence, first in a narrow target setting, then (III) in an extended range of settings and for various outcomes, accompanied by appropriate application examples, and (IV) investigations that establish a method as sufficiently well‐understood to know when it is preferred over others and when it is not; that is, its pitfalls. We suggest basic definitions of the four phases to provoke thought and discussion rather than devising an unambiguous classification of studies into phases. Too many methodological developments finish before phase III/IV, but we give two examples with references. Our concept rebalances the emphasis to studies in phases III and IV, that is, carefully planned method comparison studies and studies that explore the empirical properties of existing methods in a wider range of problems.