bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficient and Stable Deep‐Blue Fluorescent Organic Light‐Emitting Diodes Employing a Sensitizer with Fast Triplet Upconversion
Authors: Zhang Dongdong , Song Xiaozeng , Gillett Alexander J. , Drummond Bluebell H. , Jones Saul T. E. , Li Guomeng , He Hanqing , Cai Minghan , Credgington Dan , Duan Lian 
Published: April 2020

AbstractMultiple donor–acceptor‐type carbazole–benzonitrile derivatives that exhibit thermally activated delayed fluorescence (TADF) are the state of the art in efficiency and stability in sky‐blue organic light‐emitting diodes. However, such a motif still suffers from low reverse intersystem crossing rates (kRISC) with emission peaks <470 nm. Here, a weak acceptor of cyanophenyl is adopted to replace the stronger cyano one to construct blue emitters with multiple donors and acceptors. Both linear donor–π–donor and acceptor–π–acceptor structures are observed to facilitate delocalized excited states for enhanced mixing between charge‐transfer and locally excited states. Consequently, a high kRISC of 2.36 × 106 s−1 with an emission peak of 456 nm and a maximum external quantum efficiency of 22.8% is achieved. When utilizing this material to sensitize a blue multiple‐resonance TADF emitter, the corresponding device simultaneously realizes a maximum external quantum efficiency of 32.5%, CIEy ≈ 0.12, a full width at half maximum of 29 nm, and a T80 (time to 80% of the initial luminance) of > 60 h at an initial luminance of 1000 cd m−2.
Colorful Diamond‐Like Carbon Films from Different Micro/Nanostructures
Authors: Zhou Xiaolong , Zheng Yongping , Shimizu Takuya , Euaruksakul Chanan , Tunmee Sarayut , Wang Tao , Saitoh Hidetoshi , Tang Yongbing 
Published: April 2020

AbstractThe coloration is one kind of interesting and important properties of diamond‐like carbon (DLC) films, but lack of in‐depth study. The micro/nanostructure composition of material determines its macroscopic properties. Here, the Commission Internationale de I'Eclairage (CIE) color space, quantitative micro/nanostructure composition analysis, and ab initio molecular‐dynamics simulations are used to quantitatively analyze the generation mechanism for coloration of DLC films. It is found that as a typical amorphous thin film, the generation of DLC film coloration can be explained by the thin film interference and amorphous photonic crystal structural color theory, but the generation mechanisms of coloration for different types of DLC films are not the same. The micro/nanostructure in terms of hydrogen content and carbon atom state plays vital roles in the generation of DLC film structural colors and even determines whether the noniridescent structure color exists or not. These results demonstrate the possibility of utilizing the human eyes to directly distinguish different types of DLC films and accelerate the application of DLC film in energy saving, optical filter, sensor, color gradient coating, advanced luxury products, and bionics fields.
Tuning Multimode Luminescence in Lanthanide(III) and Manganese(II) Co‐Doped CaZnOS Crystals
Authors: Zhang Xin , Zhao Jianxiong , Chen Bing , Sun Tianying , Ma Ronghua , Wang Yu , Zhu Haomiao , Peng Dengfeng , Wang Feng 
Published: April 2020

AbstractMultimode luminescence with tunable optical properties is reported in lanthanide(III) and manganese(II) co‐doped CaZnOS crystals. The materials display distinct emissions under excitations of X‐ray, ultraviolet, and near‐infrared photons as well as mechanical action, respectively. The excitation dependence of emission spectra stems from varying host‐to‐dopant and dopant‐to‐dopant energy transfer processes involved in different luminescence modes. By controlling intracrystal energy transfer through control of dopant concentration and combination, the emission spectra are precisely tuned across the visible to near‐infrared. These findings highlight a facile approach to constructing multimode luminescent materials with intrinsically encrypted emission characteristics for advanced anticounterfeiting applications.
Changes in soil chemical properties and crop yields with long‐term cropping system and nitrogen fertilization
Authors: Sainju Upendra M. , Alasinrin Sikiru Y. 
Published: April 2020

AbstractInformation is needed on the long‐term impact of cropping system and N fertilization on dryland soil health and crop yields. We studied the 13‐yr effect of cropping system and N fertilization rate on soil chemical properties at the 0‐ to 60‐cm depth and related them to annualized crop yield in the northern Great Plains. Cropping systems were conventional tillage barley (Hordeum vulgare L.)/spring wheat (Triticum aestivum L)–fallow (CTB/WF), no‐tillage barley/spring wheat–fallow (NTB/WF), no‐tillage barley/spring wheat–pea (Pisum sativum L) (NTB/WP), and no‐tillage continuous barley/spring wheat (NTCB/W). Nitrogen fertilization rates were 0, 40, 80, and 120 kg N ha−1 to barley planted from 2006 to 2011 and 0, 50, 100, and 150 kg N ha−1 to spring wheat planted from 2012 to 2018. At 0 to 5 cm, soil pH and CEC were greater with NTB/WP than NTCB/W and CTB/WF, and soil organic matter (SOM) and Olsen‐P were greater with NTCB/W than CTB/WF. Increased N rate reduced soil pH, K, Ca, Mg, and CEC at most soil depths. Annualized crop yield was greater with NTCB/W and NTB/WP than NTB/WF and CTB/WF and maximized at 80–100 kg N ha−1. Most soil chemical properties induced by N fertilization were negatively correlated, but Mg concentration at 30–60 cm induced by cropping system was positively correlated with annualized crop yield. No‐till barley/spring wheat–pea rotation with 80–100 kg N ha−1 can sustain dryland soil chemical properties and barley and spring wheat yields in the northern Great Plains.
Ultrathin ZnIn2S4 Nanosheets Anchored on Ti3C2TX MXene for Photocatalytic H2 Evolution
Authors: Zuo Gancheng , Wang Yuting , Teo Wei Liang , Xie Aming , Guo Yang , Dai Yuxuan , Zhou Weiqiang , Jana Deblin , Xian Qiming , Dong Wei , Zhao Yanli 
Published: April 2020

AbstractPhotocatalysts derived from semiconductor heterojunctions that harvest solar energy and catalyze reactions still suffer from low solar‐to‐hydrogen conversion efficiency. Now, MXene (Ti3C2TX) nanosheets (MNs) are used to support the in situ growth of ultrathin ZnIn2S4 nanosheets (UZNs), producing sandwich‐like hierarchical heterostructures (UZNs‐MNs‐UZNs) for efficient photocatalytic H2 evolution. Opportune lateral epitaxy of UZNs on the surface of MNs improves specific surface area, pore diameter, and hydrophilicity of the resulting materials, all of which could be beneficial to the photocatalytic activity. Owing to the Schottky junction and ultrathin 2D structures of UZNs and MNs, the heterostructures could effectively suppress photoexcited electron–hole recombination and boost photoexcited charge transfer and separation. The heterostructure photocatalyst exhibits improved photocatalytic H2 evolution performance (6.6 times higher than pristine ZnIn2S4) and excellent stability.
A Cation and Anion Dual Doping Strategy for the Elevation of Titanium Redox Potential for High‐Power Sodium‐Ion Batteries
Authors: Chen Mingzhe , Xiao Jin , Hua Weibo , Hu Zhe , Wang Wanlin , Gu Qinfen , Tang Yuxin , Chou Shu‐Lei , Liu Hua‐Kun , Dou Shi‐Xue 
Published: April 2020

AbstractTitanium‐based polyanions have been intensively investigated for sodium‐ion batteries owing to their superior structural stability and thermal safety. However, their low working potential hindered further applications. Now, a cation and anion dual doping strategy is used to boost the redox potential of Ti‐based cathodes of Na3Ti0.5V0.5(PO3)3N as a new cathode material for sodium ion batteries. Both the Ti3+/Ti4+ and V3+/V4+ redox couples are reversibly accessed, leading to two distinctive voltage platforms at ca. 3.3 V and ca. 3.8 V, respectively. The remarkably improved cycling stability (86.3 %, 3000 cycles) can be ascribed to the near‐zero volume strain in this unusual cubic symmetry, which has been demonstrated by in situ synchrotron‐based X‐ray diffraction. First‐principles calculations reveal its well‐interconnected 3D Na diffusion pathways with low energy barriers, and the two‐sodium‐extracted intermediate NaTi0.5V0.5(PO3)3N is also a stable phase according to formation energy calculations.
Anthraquinone Redox Relay for Dye‐Sensitized Photo‐electrochemical H2O2 Production
Authors: Sun Jiaonan , Wu Yiying 
Published: April 2020

AbstractAnthraquinone (AQ) redox mediators are introduced to metal‐free organic dye sensitized photo‐electrochemical cells (DSPECs) for the generation of H2O2. Instead of directly reducing O2 to produce H2O2, visible‐light‐driven AQ reduction occurs in the DSPEC and the following autooxidation with O2 allows H2O2 accumulation and AQ regeneration. In an aqueous electrolyte, under 1 sun conditions, a water‐soluble AQ salt is employed with the highest photocurrent of up to 0.4 mA cm−2 and near‐quantitative faradaic efficiency for producing H2O2. In a non‐aqueous electrolyte, under 1 sun illumination, an organic‐soluble AQ is applied and the photocurrent reaches 1.8 mA cm−2 with faradaic efficiency up to 95 % for H2O2 production. This AQ‐relay DSPEC exhibits the highest photocurrent so far in non‐aqueous electrolytes for H2O2 production and excellent acid stability in aqueous electrolytes, thus providing a practical and efficient strategy for visible‐light‐driven H2O2 production.
Controlled‐Atmosphere Flame Fusion Single‐Crystal Growth of Non‐Noble fcc, hcp, and bcc Metals Using Copper, Cobalt, and Iron
Authors: Schuett Fabian M. , Esau Derek , Varvaris K. Liam , Gelman Shelly , Björk Jonas , Rosen Johanna , Jerkiewicz Gregory , Jacob Timo 
Published: April 2020

AbstractThe growth of noble‐metal single crystals via the flame fusion method was developed in the 1980s. Since then, there have been no major advancements to the technique until the recent development of the controlled‐atmosphere flame fusion (CAFF) method to grow non‐noble Ni single crystals. Herein, we demonstrate the generality of this method with the first preparation of fcc Cu as well as the first hcp and bcc single crystals of Co and Fe, respectively. The high quality of the single crystals was verified using scanning electron microscopy and Laue X‐ray backscattering. Based on Wulff constructions, the equilibrium shapes of the single‐crystal particles were studied, confirming the symmetry of the fcc, hcp, and bcc single‐crystal lattices. The low cost of the CAFF method makes all kinds of high‐quality non‐noble single crystals independent of their lattice accessible for use in electrocatalysis, electrochemistry, surface science, and materials science.
Multiplexed Discrimination of Single Amino Acid Residues in Polypeptides in a Single SERS Hot Spot
Authors: Huang Jian‐An , Mousavi Mansoureh Z. , Giovannini Giorgia , Zhao Yingqi , Hubarevich Aliaksandr , Soler Miguel A. , Rocchia Walter , Garoli Denis , De Angelis Francesco 
Published: April 2020

AbstractThe SERS‐based detection of protein sequences with single‐residue sensitivity suffers from signal dominance of aromatic amino acid residues and backbones, impeding detection of non‐aromatic amino acid residues. Herein, we trap a gold nanoparticle in a plasmonic nanohole to generate a single SERS hot spot for single‐molecule detection of 2 similar polypeptides (vasopressin and oxytocin) and 10 distinct amino acids that constitute the 2 polypeptides. Significantly, both aromatic and non‐aromatic amino acids are detected and discriminated at the single‐molecule level either at individual amino acid molecules or within the polypeptide chains. Correlated with molecular dynamics simulations, our results suggest that the signal dominance due to large spatial occupancy of aromatic rings of the polypeptide sidechains on gold surfaces can be overcome by the high localization of the single hot spot. The superior spectral and spatial discriminative power of our approach can be applied to single‐protein analysis, fingerprinting, and sequencing.
Ligand‐Enabled γ‐C(sp3)−H Olefination of Free Carboxylic Acids
Authors: Ghosh Kiron Kumar , Uttry Alexander , Mondal Arup , Ghiringhelli Francesca , Wedi Philipp , van Gemmeren Manuel 
Published: April 2020

AbstractWe report the ligand‐enabled C−H activation/olefination of free carboxylic acids in the γ‐position. Through an intramolecular Michael addition, δ‐lactones are obtained as products. Two distinct ligand classes are identified that enable the challenging palladium‐catalyzed activation of free carboxylic acids in the γ‐position. The developed protocol features a wide range of acid substrates and olefin reaction partners and is shown to be applicable on a preparatively useful scale. Insights into the underlying reaction mechanism obtained through kinetic studies are reported.
Unveiling the Role of DJ‐1 Protein in Vesicular Storage and Release of Catecholamine with Nano/Micro‐Tip Electrodes
Authors: Yue Qingwei , Li Xianchan , Wu Fei , Ji Wenliang , Zhang Yue , Yu Ping , Zhang Meining , Ma Wenjie , Wang Ming , Mao Lanqun 
Published: April 2020

AbstractDJ‐1 protein deficiency caused by PARK7 gene mutation has been suggested to closely relate to Parkinson's disease (PD), mainly through the attenuation D2 dopamine receptor activity in mice; however, whether or how it affects the vesicular storage and exocytosis of neurochemicals remains unclear. By using electrochemical methods at a single vesicle/cell level with nano/micro‐tip electrodes, we for the first time find that DJ‐1 protein deficiency caused by PARK7 gene knockout (KO) in mice has little effect on vesicular catecholamine content but significantly prolongs the exocytotic events, especially the closing time of exocytotic fusion pores. Further studies suggest the inhibition of α‐synuclein aggregation by DJ‐1 protein might be one way that DJ‐1 protein acts on neurotransmission. This finding offers the first direct link between DJ‐1 protein deficiency and vesicular chemical storage and release of chemicals, providing a new chemical insight into the pathology of PD caused by PARK7 gene mutation.
A Precious‐Metal‐Free Hybrid Electrolyzer for Alcohol Oxidation Coupled to CO2‐to‐Syngas Conversion
Authors: Bajada Mark A. , Roy Souvik , Warnan Julien , Abdiaziz Kaltum , Wagner Andreas , Roessler Maxie M. , Reisner Erwin 
Published: April 2020

AbstractElectrolyzers combining CO2 reduction (CO2R) with organic substrate oxidation can produce fuel and chemical feedstocks with a relatively low energy requirement when compared to systems that source electrons from water oxidation. Here, we report an anodic hybrid assembly based on a (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl (TEMPO) electrocatalyst modified with a silatrane‐anchor (STEMPO), which is covalently immobilized on a mesoporous indium tin oxide (mesoITO) scaffold for efficient alcohol oxidation (AlcOx). This molecular anode was subsequently combined with a cathode consisting of a polymeric cobalt phthalocyanine on carbon nanotubes to construct a hybrid, precious‐metal‐free coupled AlcOx–CO2R electrolyzer. After three‐hour electrolysis, glycerol is selectively oxidized to glyceraldehyde with a turnover number (TON) of ≈1000 and Faradaic efficiency (FE) of 83 %. The cathode generated a stoichiometric amount of syngas with a CO:H2 ratio of 1.25±0.25 and an overall cobalt‐based TON of 894 with a FE of 82 %. This prototype device inspires the design and implementation of nonconventional strategies for coupling CO2R to less energy demanding, and value‐added, oxidative chemistry.
Fabrication of Crystalline Microporous Membrane from 2D MOF Nanosheets for Gas Separation
Authors: Jiang Shuangshuang , Shi Xinli , Sun Fuxing , Zhu Guangshan 
Published: April 2020

AbstractMetal‐organic frameworks (MOFs)‐based membranes have shown great potentials as applications in gas separation. In this work, a uniform membrane based on 2D MOF Ni3(HITP)2 (HITP=2,3,6,7,10,11‐hexaaminotriphenylene) was fabricated on ordered macroporous AAO via the filtration method. To fabricate the membrane, we obtained the Ni3(HITP)2 nanosheets as building blocks via a soft‐physical exfoliation method successfully that were confirmed by AFM and TEM. We also studied the H2, CO2 and N2 adsorption isotherms of Ni3(HITP)2 powder at room temperature, which shows Ni3(HITP)2 has high heats of adsorption for CO2 and high selectivity of CO2 over N2. Gas permeation tests indicate that the Ni3(HITP)2 membrane shows high permeance and selectivity of CO2 over N2, as well as good selectivity of H2 over N2. The ideal separation factors of CO2/N2 and H2/N2 from sing‐gas permeances are 13.6 and 7.8 respectively, with CO2 permeance of 3.15×10−6 mol⋅m−2⋅s−1⋅Pa−1. The membrane also showed good stability, durability and reproducibility, which are of potential interest for practical applications in the CO2 separations.
Leben zwischen Eis und Felsen
Authors: Kanz Birgit , Büdel Burkhard , Jung Patrick , Karsten Ulf , Printzen Christian 
Published: April 2020

ZusammenfassungTrotz ihrer widrigen Umweltbedingungen und geografischen Isolation beherbergt die Antarktis eine reiche Vegetation aus Flechten, Moosen, Algen, Pilzen und Bakterien. In den milderen Gebieten der maritimen und kontinentalen Antarktis bilden diese Pionierarten weithin sichtbare biologische Bodenkrusten. In trockeneren Gebieten kommen sie hauptsächlich in den äußeren Gesteins‐ und oberen Bodenschichten vor. Unter den ökologischen Anpassungen, die diesen Arten das Überleben unter antarktischen Bedingungen ermöglichen, sticht besonders eine gute Austrocknungstoleranz hervor. Über die genetische Vielfalt der meisten Arten weiß man noch so gut wie nichts. Während einige Arten wohl in der Antarktis entstanden sind, sind andere relativ späte Neubesiedler.
Chemical profiling and characterization of phenolic acids, flavonoids, terpene glycosides from Vangueria agrestis using ultra‐high‐performance liquid chromatography/ion mobility quadrupole time‐of‐flight mass spectrometry and metabolomics approach
Authors: Avula Bharathi , Bae Ji‐Yeong , Wang Yan‐Hong , Wang Mei , Osman Ahmed Galal , Smith Kerri , Yuk Jimmy , Ali Zulfiqar , Plumb Robert , Isaac Giorgis , Khan Ikhlas A. 
Published: April 2020

AbstractVangueria agrestis is a shrub indigenous to tropical Africa, belonging to family Rubiaceae and is traditionally used as a decoction for treatment of fever, pain, and malaria. This study was undertaken to investigate the chemical constituents based on precursor exact mass and fragment ion information. The chemical profiling and structural characteristics of chemical constituents from methanolic extracts of dried aerial parts and roots of V. agrestis and dietary supplements were analyzed using ultra‐high‐performance liquid chromatography/ion mobility quadrupole time‐of‐flight mass spectrometry coupled with UNIFI platform and multivariate analysis in both negative and positive ion modes. A non‐targeted ultra‐high‐performance liquid chromatography‐mass spectrometry analysis was carried out to profile the chemical constituents of crude extracts of V. agrestis, and 73 compounds, including reference compounds, were identified. The fragments of flavonoids, monoterpene, and triterpene glycosides revealed the characteristic cleavage of glycosidic linkages, and the fragmentation pattern provided the identity of the sugars. This analytical method provides a quick method for quality assessment of dietary supplements. Finally, a chemometrics approach with multivariate statistical tools was used to visualize the differences between root and aerial parts of plant samples and to find the potential chemical markers that differentiate among these parts of V. agrestis samples and dietary supplements.
Ultrafine Mo2C Nanoparticles Confined in 2D Meshlike Carbon Nanolayers for Effective Hydrogen Evolution
Authors: Liu Rui , Du Qianqian , Zhao Ruihua , Nie Xiaorong , Liu Lu , Li Jinping , Du Jianping 
Published: April 2020

AbstractElectrochemical water splitting has been considered as a promising method for large‐scale hydrogen production. However, the development of high‐performance and low‐cost noble metal‐free electrocatalysts for hydrogen evolution reaction (HER) remains a great challenge. Transition metal carbides (such as molybdenum carbide) are one of the most potential substitutes for noble metal as electrocatalysts for HER. One of the effective measures for further enhancing their performances is to hinder the coalescence of nanoparticles. Here we demonstrate a two‐dimensional ultrafine molybdenum carbide‐coupled mesoporous structured meshlike carbon nanolayers synthesized vis facile route based on holes in the carbon nanolayer structures blocking nanoparticle agglomeration. Molybdenum carbide clusters dispersed on the carbon nanolayers are successfully prepared by carbonization of molybdate‐polyvinylpyrrolidone precursor as a proof of concept, which exhibits excellent electrocatalytic activity for the HER and high stability in basic medium. The present study provides some references for the design and synthesis of nanostructured electrocatalysts utilizing 2D meshlike materials to prevent nanoparticles from agglomerating.
Nitrogen‐Doped Mesoporous Carbon Electrodes Prepared from Templating Propylamine‐Functionalized Silica
Authors: Brandiele Riccardo , Poli Federico , Picelli Luca , Pilot Roberto , Rizzi Gian Andrea , Soavi Francesca , Durante Christian 
Published: April 2020

AbstractIn this paper, nitrogen doped carbon materials with mesopores 4–8 nm‐wide and a high surface area of ca.1100 m2 g−1 were synthesized according to an innovative hard template method. Sucrose was used as carbon source and propylamine functionalized silica acted as both nitrogen source and templating agent. The novel doped carbons were compared with mesoporous carbons featuring similar texture properties (pore size and surface area) but obtained by the pyrolysis of sucrose or 1,10‐phenantholine and employing non‐functionalized silica as a templating agent. The interest of this investigation is to understand how doping occurs when a functionalized silica is employed, and whether the nitrogen doping remains a surface property or it is extended also to the bulk of the material, influencing the morphological and the electrical properties of the resulting carbon. X‐ray photoemission spectroscopy, elemental analysis, and EDX confirmed the doping action of the functionalized silica and the electrochemical characterization allowed to compare the different performances as supercapacitor materials.
Microporous Organic Nanoparticles Anchoring CeO2 Materials: Reduced Toxicity and Efficient Reactive Oxygen Species‐Scavenging for Regenerative Wound Healing
Authors: Kim Dong Wook , Le Thai Minh Duy , Lee Sang Moon , Kim Hae Jin , Ko Yoon‐Joo , Jeong Ji Hoon , Thambi Thavasyappan , Lee Doo Sung , Son Seung Uk 
Published: April 2020

AbstractThis work shows that microporous organic polymer can be applied to the engineering of CeO2‐based antioxidant nanomaterials for in vivo regenerative wound healing. Whilst nanoparticulate CeO2 has shown excellent redox quenching of reactive oxygen species (ROS) because it is rich in oxygen defects and Ce3+ species, it has a strong tendency to form aggregates because it is a kinetic intermediate of bulk materials. Anchoring of nanoparticulate CeO2 on suitable supports can be an efficient anti‐aggregation strategy. In this work, CeO2 nanoparticles were immobilized on microporous organic nanoparticles (MONPs) to form MONP@CeO2 nanocomposites. Compared to CeO2 materials, the MONP@CeO2 nanocomposites showed not only efficient ROS scavenging in in vivo regenerative wound healing but also reduced cytotoxicity in in vitro cell studies, due to the efficient distribution and dilution effect of CeO2 nanomaterials.