bluuebunny/crossref_metadata_2025_split huggingface dataset:
Near‐Infrared Light/Thermal Dual‐Responsive Epoxy‐Based Polydiacetylene Composite for 3D Printing
Authors: Liu Shaohui , Ding Zhaofu , Zhu Haibin , Gree Simon , Xiao Pu , Xu Yangyang , Lalevée Jacques 
Published: October 2021

AbstractPolydiacetylene (PDA) is a promising material due to the chromatic transition through external stimulus. However, near‐infrared (NIR) light is on the periphery of attention to achieve the colorimetric change. Herein, an epoxy‐based PDA composite is prepared through a dual‐wavelength orthogonal photopolymerization strategy where 405 nm light and UV light are utilized in turn. The appearance of blue phase indicates that ene–yne‐conjugated PDA backbone is successfully formed in the composite. The generated PDA composite exhibits a blue‐to‐red color change upon heating. More interestingly, the fast chromatic transition is also observed under a laser diode at 1064 nm irradiation in the presence of a NIR dye (IR 1064). And such NIR light responsiveness of the composite upon NIR light irradiation is demonstrated by thermal imaging camera. Finally, the 3D printing technique is applied to the composite and the fabricated 3D pattern exhibits dual colorimetric transition in response to both heat and NIR light stimuli. Therefore, the newly proposed approach finds great applications in functional materials due to the unique dual thermal or NIR light stimuli responsiveness.
ZnO Nanoflakes Embedded Polymer Matrix for High‐Performance Mechanical Energy Harvesting
Authors: Manchi Punnarao , Graham Sontyana Adonijah , Patnam Harishkumarreddy , Paranjape Mandar Vasant , Yu Jae Su 
Published: October 2021

AbstractNanogenerators have attracted much attention in the past few years due to their high conversion efficiency of mechanical energy into electrical energy that is abundantly available in the environment and everyday human life. Enhancing the electrical output performance of nanogenerator using composite polymeric films (CPFs), i.e., piezoelectric materials embedded in triboelectric polymers, has gained potential interest. The CPFs can provide a high relative permittivity and enhanced surface charge density, resulting in an enhanced electrical output. Herein, piezoelectric zinc oxide (ZnO) nanoflakes (ZnO‐NFs) were synthesized by a hydrothermal reaction process and combined with a nylon polymer to prepare a positive triboelectric composite film. Furthermore, a piezo/triboelectric hybrid nanogenerator (ZnO‐HNG) was fabricated with the prepared nylon/ZnO composite film as a positive triboelectric material and PDMS as a negative triboelectric material, respectively. The effect of the loading concentration of the ZnO‐NFs in the nylon polymer on the electrical output was systematically investigated. The optimized ZnO‐HNG exhibited a stable and enhanced electrical output performance with the voltage, current, charge density, and power density values of ≈300 V, ≈9 µA, ≈85 μC m−2, and ≈4.5 W m−2, respectively. Finally, the ZnO‐HNG was attached to the human body to harvest various mechanical motions involved in everyday human life and power various low‐power portable electronics.
Slow Energy Transfer in Self‐Doped β‐Conformation Film of Steric Polydiarylfluorenes toward Stable Dual Deep‐Blue Amplified Spontaneous Emission
Authors: Xu Man , Sun Lili , Wang Shengjie , Lin Jinyi , Yu Mengna , Wang Xuhua , Stavrinou Paul N. , Xie Linghai , Cheetham Nathan J. , Ding Xuehua , Bradley Donal D. C. , Huang Wei 
Published: October 2021

AbstractExciton behavior is crucial for improving the optoelectronic property of a light‐emitting conjugated polymer. Herein, the photoexcitation dynamics of exciton migration and energy transfer in a self‐doped β‐conformation film of the polydiarylfluorenes (poly[4‐(octyloxy)‐9,9‐diphenylfluoren‐2,7‐diyl]‐co‐[5‐(octyloxy)‐9,9‐ diphenylfluoren‐2,7‐diyl], PODPF) are demonstrated. Compared to the first generation of the β‐conformation polyfluorene, poly(9,9‐dioctylfluorene) (PFO), energy transfer occurs in PODPF β‐conformation films in a time period of ≈150 ps, much longer than those of the PFO ones (<5 ps), associated with the effective intrachain energy transfer (few hundred picoseconds), rather than interchain Förster energy transfer (a few picoseconds). Similar to PFO, the PODPF β‐conformation also displays well‐resolved vibronic emission peaks at 20 K, attributed to the planar and rigid conformation. Interestingly, a residual 0‐0 band emission of nonplanar conformation chain segments (435 nm, 2.85 eV) at 20 K also further confirms the exciton migration from the amorphous state to the β‐conformation domain in PODPF films. Therefore, the stable dual amplified spontaneous emission (ASE) behavior of the PODPF self‐doped films at 461 nm (2.69 eV) and 483 nm (2.57 eV), originates from the individual amorphous and β‐conformation domains.
Impurity‐Induced Robust Trionic Effect in Layered Violet Phosphorus
Authors: Li Yanyong , Cai Songhua , Lai Wai Kin , Wang Chenhao , Rogée Lukas , Zhuang Lyuchao , Zhai Lingling , Lin Shenghuang , Li Mingjie , Lau Shu Ping 
Published: October 2021

AbstractTrionic effect is a vital excitonic physical phenomenon, which intensively affects the optical and optoelectronic properties of 2D materials. Violet phosphorus (VP) is another allotrope of elemental phosphorus with robust photoluminescence (PL) emission in the visible range. So far, experimental investigations of the excitonic behavior in VP are quite scarce. Herein, the evolution of the PL mechanism in synthesized VP crystals against the Ar+ plasma exposure is investigated with emphasis on a conversion from trion to exciton emission. The estimated trion binding energy of VP is ≈109 meV, relatively larger than common layered materials. By analyzing the chemical states and the atomic structures, the conversion mechanism is proposed as follows. The Ar+ plasma treatment reduces the stannous SnIP impurities’ population, which are incorporated into the VP lattices and serve as the n‐type dopants leading to the trion formation. Besides, various surface defects (POx) can promote the trion‐to‐exciton conversion by withdrawing electrons from VP in the process and act as hole‐trap centers to enhance the photodetection of VP phototransistors. This work reveals that the layered VP crystal can provide an ideal platform to study the excitonic physics and future trionic devices at the 2D limit.
1D Chiral Lead Halide Perovskites with Superior Second‐Order Optical Nonlinearity
Authors: Zheng Yongshen , Xu Jialiang , Bu Xian‐He 
Published: October 2021

AbstractChiral hybrid perovskites have shown great potential for applications in next‐generation optoelectronic devices. The intrinsic asymmetric structures of these chiral hybrid perovskites make them particularly promising for second‐order nonlinear optics (NLO). However, it remains still a challenge to obtain ideal perovskite NLO crystals featuring simultaneously large NLO coefficient, good optical transparency, high laser damage threshold, and stable physical and chemical properties, which are highly desirable for practical applications. Herein, a series is constructed of 1D chiral lead halide hybrid perovskites (R/S‐2‐MPD)PbX3 (2‐MPD = 2‐methylpiperidine; X = Cl, Br, I) featuring non‐centrosymmetric architectures. Among them, the (R/S‐2‐MPD)PbBr3 perovskites demonstrate superior performances in second‐order optical nonlinearity, including a large second‐harmonic generation coefficient (≈29.9 pm V–1), wide transparency region (λUV ≈ 310 nm), high laser damage threshold (≈2.84 mJ cm–2), high polarization ratio (up to 96%), and robust physical and chemical stabilities. Such a balanced performance of the chiral lead halide perovskites promises their advanced application in next‐generation photonics devices.
Parametric Analysis of Variable Stator Vane System in Gas Turbines Based on Cosimulation of its Refined Model and System Dynamic Performance Model
Authors: Jia Xingyun , Zhou Dengji , Huang Dawen , Xiao Wang , Xu Luyao , Hao Jiarui 
Published: October 2021

AbstractThe variable stator vane (VSV) system is a key component of gas turbine supercharged rotor components for anti‐surge, and its performance directly affects the working stability and economy of the gas turbine. The effect of the VSV system on the dynamic characteristics and control performance of the gas turbine cannot be known. Then a refined model of the VSV system refined to design parameters established and studied to explore the effect of gas turbine dynamic performance based on co‐simulation. The effects of key parameters on the performance of the gas turbine system are analyzed by embedding the refined VSV model into the engine model. The simulation results prove that servo amplifier gain, viscous friction coefficient and dead band are sensitive structural parameters that affect the dynamic performance of the gas turbines. In the proposed appropriate interval, the optimal sensitive parameters can reduce the overshoot and adjustment time by about 51% and 7%. The gain of the servo amplifier is positively correlated with the maximum opening of the VSV. When the dynamic performance of the control system has been exerted to its extreme, some nonlinear parameters of the actuator can greatly improve the overall performance of the complex system.
3D Porous Metallic Boron Carbide Crystal Structure with Excellent Ductility
Authors: Hussain Kashif , Muhammad Imran , Wu Wei , Qie Yu , Mahmood Tariq , Sun Qiang 
Published: October 2021

AbstractIt is well established that metal atoms can be used to regulate porosity in synthesis and porous structures can be obtained by removing metal atoms. Motivated by a recent synthesis of 2Sr@B6C6, it is found that when Sr atoms are removed, the resulting 3D porous BC structure (3D‐B6C6) with reduced symmetry is stable thermally, dynamically, and mechanically. More importantly, different from the widely studied semiconducting B‐rich boron carbides, the 3D‐B6C6 is metallic; And different from C‐rich boron carbides with high hardness and brittleness, the 3D‐B6C6 is found to be a novel 3D boron carbide crystal showing excellent ductility with Pugh's ratio of 2.24, low Vickers hardness of 8.66 GPa, and universal anisotropy index of 2.62. This study expands the boron carbides family with new features.
Flexible All‐Inorganic Room‐Temperature Chemiresistors Based on Fibrous Ceramic Substrate and Visible‐Light‐Powered Semiconductor Sensing Layer
Authors: Han Chaohan , Li Xiaowei , Liu Yu , Tang Yujing , Liu Mingzhuang , Li Xinghua , Shao Changlu , Ma Jiangang , Liu Yichun 
Published: October 2021

AbstractAs the most extensively used gas‐sensing devices, inorganic semiconductor chemiresistors are facing great challenges in realizing mechanical flexibility and room‐temperature gas detection for developing next‐generation wearable sensing devices. Herein, for the first time, flexible all‐inorganic yttria‐stabilized zirconia (YSZ)/In2O3/graphitic carbon nitride (g‐C3N4) (ZIC) gas sensor is designed by employing YSZ nanofibers as substrate, and ultrathin In2O3/g‐C3N4 heterostructures as active sensing layer. The YSZ substrate possesses small nanofiber diameter (310 nm), ultrafine grain size (23.9 nm), and abundant dangling bonds, endowing it with striking mechanical flexibility and strong adhesion with In2O3/g‐C3N4 sensing layer. Meanwhile, the ultrathin thickness (≈7 nm) of In2O3/g‐C3N4 ensures that the inorganic sensing layer has tiny linear strain along with the deformation of flexible YSZ substrate, thereby enabling unusual bending capacity. To address the operating temperature issue, the gas sensor is operated by using a visible‐light‐powered strategy. Under visible‐light illumination, the flexible ZIC sensor exhibits a perfectly reversible response/recovery dynamic process and ultralow detection limit of 50 ppb to toxic nitrogen dioxide at room temperature. This work not only provides an insight into the mechanical flexibility of inorganic materials, but also offers a valuable reference for developing other flexible inorganic‐semiconductor‐based room‐temperature gas sensors.
MnCo2S4‐CoS1.097 Heterostructure Nanotubes as High Efficiency Cathode Catalysts for Stable and Long‐Life Lithium‐Oxygen Batteries Under High Current Conditions
Authors: Xia Qing , Zhao Lanling , Zhang Zhijia , Wang Jun , Li Deyuan , Han Xue , Zhou Zhaorui , Long Yuxin , Dang Feng , Zhang Yiming , Chou Shulei 
Published: October 2021

AbstractConstructing the heterostructures is considered to be one of the most effective methods to improve the poor electrical conductivity and insufficient electrocatalytic properties of metal sulfide catalysts. In this work, MnCo2S4‐CoS1.097 nanotubes are successfully prepared via a reflux‐ hydrothermal process. This novel cathode catalyst delivers high discharge/charge specific capacities of 21 765/21 746 mAh g−1 at 200 mA g−1 and good rate capability. In addition, a favorable cycling stability with a fixed specific capacity of 1000 mAh g−1 at high current density of 1000 mA g−1 (167 cycles) and 2000 mA g−1 (57 cycles) are delivered. It is proposed that fast transmission of ions and electrons accelerated by the built‐in electric field, multiple active sites from the heterostructure, and nanotube architecture with large specific surface area are responsible for the superior electrochemical performance. To some extent, the rational design of this heterostructured metal sulfide catalyst provides guidance for the development of the stable and efficient cathode catalysts for Li‐O2 batteries that can be employed under high current conditions.
Enhancement of Interfacial Polarization in BaTiO3 Thin Films via Oxygen Inhomogeneity
Authors: Li Zhipeng , Zhang Zeyu , Liu Jia , Zhu Ruixue , Ge Binghui , Li Yueliang , Zhang Xin , Gao Peng , Wang Dawei , Xu Xiaoguang , Tian Wenhuai , Jiang Yong 
Published: October 2021

AbstractEnhancement of interfacial ferroelectricity is crucial for the development of nanoscale ferroelectric devices, such high density and nonvolatile memory. Although the epitaxial strain can lead to improved properties, the limited choices of substrates and strain relaxation have hindered the further tuning of ferroelectricity by strain engineering. To overcome this limitation, the interaction between polarization and defects is regarded as a potential route to enhance the interfacial polarization. Here, a universal method to achieve a polarization‐enhanced interface by tuning the distribution of oxygen in lead‐free BaTiO3 films is demonstrated. The interfacial phase processes largely increased c‐axis lattice constant, tetragonality, and about 100% increasement of Ti atom displacement near interface within thickness of 8 unit cells, suggesting enhancement of spontaneous polarization up to 70 μC cm‐2. The gradient distribution of oxygen along c‐axis is also revealed. In addition, the first‐principle Monte Carlo simulation of the tetragonality and polarization support the experimental results. It is suggested that the inhomogeneity of oxygen and interfacial charges could induce an electric field and further enhance the interfacial polarization. This work provides a new route of utilizing the oxygen distribution to engineer the ferroelectrics and paves the way for the development of nanoscale ferroelectric devices.
Multimodal Approach towards Large Area Fully Semitransparent Perovskite Solar Module
Authors: Rai Monika , Yuan Zhengtian , Sadhu Anupam , Leow Shin Woei , Etgar Lioz , Magdassi Shlomo , Wong Lydia Helena 
Published: October 2021

AbstractSignificant advancements in the perovskite solar cells/modules (PSCs/PSMs) toward better operational stability and large area scalability have recently been reported. However, semitransparent (ST), high efficiency, and large area PSMs are still not well explored and require attention to realize their application in building‐integrated photovoltaics (BIPV). This work employs multiple synergistic strategies to improve the quality and stability of the ST perovskite film while ensuring high transparency. Europium ions, doped in the perovskite, are found to suppress the generation of detrimental species like elemental Pb and I, resulting in higher atmospheric stability. The effect of the top transparent contact is designed to obtain an average visible transparency (AVT) of >20% for full device and a green colored hue. Lastly, the lower current density due to the thinner ST absorber is enhanced by the application of a down‐converting phosphor material which harvests low energy photons and inhibits UV‐induced degradation. This multimodal approach renders a power conversion efficiency of 12% under dim light conditions and 9.5% under 1 sun illumination, respectively, on 21 cm2 ST‐PSM.
Simple Nonfused Ring Electron Acceptors with 3D Network Packing Structure Boosting the Efficiency of Organic Solar Cells to 15.44%
Authors: Wang Xiaodong , Lu Hao , Liu Yahui , Zhang Andong , Yu Na , Wang Hang , Li Song , Zhou Yuanyuan , Xu Xinjun , Tang Zheng , Bo Zhishan 
Published: October 2021

AbstractThree nonfused ring electron acceptors (NFREAs; 2Th‐2F, BTh‐Th‐2F, and 2BTh‐2F) with thieno[3,2‐b]thiophene bearing two bis(4‐butylphenyl)amino substituents as the core, 3‐octylthiophene or 3‐octylthieno[3,2‐b]thiophene as the spacer, and 3‐(1,1‐dicyanomethylene)‐5,6‐difluoro‐1‐indanone as the terminal group are designed and synthesized. The molar extinction coefficient of acceptors and the electron mobility of blend films gradually increase with increasing π‐conjugation length. Moreover, 2BTh‐2F displays a planar molecular conformation assisted by S···N and S···O intramolecular interactions. More importantly, the molecular stacking changes from 2D packing for the 2Th‐2F analog to 3D network packing for 2BTh‐2F. Due to these comprehensive merits, 2BTh‐2F:PBDB‐T‐based organic solar cells give a high power conversion efficiency of 14.53%. More impressively, when D18 is used as the donor polymer, the power conversion efficiency is further enhanced to 15.44%, which is the highest value reported for solar cells based on NFREAs.
A new phylogeny of the cladoxylopsid plexus: contribution of an early cladoxylopsid from the Lower Devonian (Emsian) of Quebec
Authors: Durieux Thibault , Lopez Madeleine A. , Bronson Allison W. , Tomescu Alexandru M. F. 
Published: October 2021

AbstractPremiseCladoxylopsids formed Earth's earliest forests and gave rise to the ancestors of sphenopsids and ferns. Lower Devonian (Emsian) strata of the Battery Point Formation (Quebec, Canada) contain new anatomically preserved cladoxylopsids, one of which is described in this article. To assess the phylogenetic position of this fossil and address questions of cladoxylopsid phylogeny, we conducted a comprehensive phylogenetic study.MethodsPermineralized axes were studied in serial sections using the cellulose acetate peel technique. We evaluated phylogenetic relationships among cladoxylopsids using a data set of 36 new morphological characters and 31 species, in parsimony‐constrained analyses.ResultsWe describe Adelocladoxis praecox gen. et sp. nov., a cladoxylopsid with small actinostelic axes bearing dichotomously branched, helically arranged ultimate appendages and fusiform sporangia. Adelocladoxis provides the oldest evidence of cladoxylopsid anatomy, including ultimate appendages and sporangia. In agreement with non‐phylogenetic classification schemes, our phylogenetic analysis resolves a basal grade of iridopterids and a clade of cladoxylopsids s.s., which includes a pseudosporochnalean cladoxylopsid clade, a cladoxylalean cladoxylopsid clade, and Adelocladoxis.ConclusionsOur phylogenetic analysis illuminates aspects of tempo and mode of evolution in the cladoxylopsid plexus. Originating prior to the Emsian, cladoxylopsids reached global distribution by the Frasnian. Iridopterids and cladoxylopsids s.s. radiated in the Emsian‐Eifelian. The sequence of character change recovered by our phylogeny supports a transition from actinostelic protosteles to dissected steles, associated with an increase in xylem rib number and medullation generating a central parenchymatous area.
New mixed ligand copper(II) hydrazone‐based complexes: Synthesis, characterization, crystal structure, DNA/RNA/BSA binding, in vitro anticancer, apoptotic activity, and cell cycle analysis
Authors: Elsayed Shadia A. , Elnabky Islam M. , di Biase Armando , El‐Hendawy Ahmed M. 
Published: October 2021

AbstractFour new mixed ligand copper(II) complexes with the general formula [Cu(L)(B)]n (1)–(4) (H2L = dehydroacetic acid benzoyl hydrazone Schiff base, B = H2O (1), DMSO (2), imidazole (imz) (3), n = 1) or pyridine (py) (4), n = 2) were synthesized. Characterization was performed by elemental analyses, FTIR, 1H NMR, electron paramagnetic resonance (EPR), ESI‐mass, and UV–visible) spectroscopy, together with magnetic susceptibility and molar conductivity measurements. The molecular structure of (2) and (4) complexes was investigated by X‐ray crystallography. The ligand behaves as a di‐basic tridentate ONO donor, coordinating to copper(II) center via deprotonated hydroxyl group, azomethine nitrogen, and deprotonated amide oxygen in a square planar (1)–(3) /square pyramidal geometry (4). The intercalation binding mode of the compounds with calf thymus DNA (ct DNA) and yeast (tRNA) and strong static interaction with bovine serum albumin (BSA) protein have been evaluated by absorption and emission spectroscopy. Further, in vitro cytotoxic activity of the compounds was examined on three human cancer cell lines; breast cancer (MCF7), colon cancer (HCT116), liver cancer (HepG2), and a normal lung fibroblast cell line (WI38) using cisplatin as a standard. Based on IC50 and therapeutic indices (TI), complexes (3) and (4) showed better activity than that of cisplatin. So both complexes were subjected for further studies viz, DNA fragmentation, cell apoptosis (annexin), and cell cycle analysis. They induced DNA fragmentation, and the HCT116 and HePG2 cell death were induced using (3) and (4) complexes, respectively, by apoptosis and cell cycle arrest at the G2/M phase.
Forcespun polyvinylpyrrolidone/copper and polyethylene oxide/copper composite fibers and their use as antibacterial agents
Authors: Hasan Md Toukir , Gonzalez Ramiro , Munoz Ari Alexis , Materon Luis , Parsons Jason G. , Alcoutlabi Mataz 
Published: October 2021

AbstractCopper nanoparticles (CuNPs) embedded in polyvinylpyrrolidone (PVP) and polyethylene oxide (PEO) fiber‐matrices were prepared through centrifugal spinning of PVP/ethanol and PEO/aqueous solutions, respectively. The prime focus of the current study is to investigate the antibacterial activity of composite fibers against Escherichia coli (E. coli) and Bacillus cereus (B. cereus) bacteria. During the fiber formation, the centrifugal spinning parameters such as spinneret rotational speed, spinneret to collector distance, and relative humidity were carefully chosen to obtain long and continuous fibers. The structural and morphological analyses of both composite fibers were investigated using scanning electron microscopy, X‐ray diffraction, energy‐dispersive X‐ray spectroscopy, and thermogravimetric analysis. In the antibacterial test, PVP/Cu and PEO/Cu composite fibrous membranes exhibited inhibition efficiency of 99.98% and 99.99% against E. coli and B. cereus bacteria, respectively. Basically, CuNPs were well embedded in the fibrous membrane at the nanoscale level, which facilitated the inhibition of bacterial functions through the inactivation of the chemical structure of the cells. Such an effective antibacterial agent obtained from forcespun composite fibers could be promising candidates for biomedical applications.