bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evolution and Conservation of Trees – A Review of Salient Issues
Authors: Kelleher Colin T. 
Published: December 2019

AbstractTrees are a charismatic group of plants bound together by life form rather than taxonomy, as the tree form occurs across most phylogenetic lineages of plants. Trees resist a rigorous definition but can broadly be defined as having secondary thickening (wood), large stature, and great longevity. This article focuses on angiosperms and addresses salient issues in the evolution of trees and highlights the current conservation practices. Although the tree form has arisen on multiple instances, evidence suggests a common origin of the woody habit. Parallel evolution and reversals in woody traits have obscured this origin; however, recent molecular evidence suggests a common origin of lignocellulosic genes involved in the production of wood. Trees tend to have high levels of heterozygosity, nevertheless a consensus has not been reached on the evolutionary potential of trees to withstand climate change and a more thorough understanding of phenotypic plasticity is essential to predict their response to short‐ and medium‐term climate change. Approximately 1% of global tree species have been genetically characterised to some extent. Direct measurement or use of indicators and proxies is needed to get a more comprehensive indication of global forest genetic resources. As large, long‐lived organisms, a dynamic or close‐to‐naturein situconservation approach, which facilitates evolution, is the most efficient option and best practice for tree conservation.
Computational Analysis of the Mutual Constraints between Single‐Cell Growth and Division Control Models
Authors: Vuaridel‐Thurre Gaëlle , Vuaridel Ambroise R. , Dhar Neeraj , McKinney John D. 
Published: December 2019

AbstractThree models of division control are proposed to achieve cell size homeostasis: sizer, timer, and adder. However, few published studies of division control take into account the dynamics of single‐cell growth and most assume that single‐cell growth is exponential. Here, computational simulations considering exponential, linear, and bilinear growth models are performed. These simulations confirm that a timer division control model alone cannot lead to size homeostasis if the single‐cell growth model is exponential. Furthermore, timer and adder division control models cannot be distinguished if the single‐cell growth model is linear. Models of division control cannot be easily differentiated by analysis of average cell behavior because the birth sizes of the majority of cells are close to the population average. However, the differences between division control models are amplified in outlier cells whose birth size is far from the average. A method is introduced for vector field analysis of the speed of convergence of outlier lineages toward the steady‐state birth size, which can help to distinguish between division control models and single‐cell growth models.
Walking the Route to GHz Solution‐Processed Organic Electronics: A HEROIC Exploration
Authors: Perinot Andrea , Passarella Bianca , Giorgio Michele , Caironi Mario 
Published: December 2019

AbstractLimited charge carrier mobility of organic semiconductors, especially for solution‐processed polymer thin films, has typically relegated organic electronics to low‐frequency operation. Nevertheless, thanks to a steady increase in electronic properties of organics, much higher operation frequencies are feasible, suggesting a possible and appealing scenario where lightweight, cost‐effective, and conformable electronics can integrate both sensing and radio‐frequency transmitting functionalities, which are the key to unlock pervasive networks of distributed sensors revolutionizing human–environment interaction. Few years ago, it was suggested that gigahertz (GHz) field‐effect transistors could be achievable even with solution‐based processes. This was the basis for the European Research Council project high‐frequency printed and direct‐written organic‐hybrid integrated circuits (HEROIC), which in the last few years investigated such unexplored path. Here, the authors report their vision toward the achievement of radio‐frequency organic electronics mainly with solution‐based and scalable processes, with reference to the experience of the HEROIC project and to some of the most notable literature examples. The authors show that the achievement of solution‐processable organic field‐effect transistors with GHz operation is indeed feasible, but requires considering a carefully revised scenario in which the main role is played by charge injection, together with the geometric overlap, the capacitive parasitism associated to fringing and some constraints on the dielectric layer thickness.
Creation of Redox‐Active PdSx Nanoparticles Inside the Defect Pores of MOF UiO‐66 with Unique Semihydrogenation Catalytic Properties
Authors: Dong Ming‐Jie , Wang Xuan , Wu Chuan‐De 
Published: December 2019

AbstractSemihydrogenation of alkynes to produce alkenes is very important in the industry; however, over‐hydrogenation heavily complicates the postprocesses, which are highly energy consuming and not environmentally friendly. One of the most efficient pathways to solve this challenging issue is to develop highly selective catalysts that could only hydrogenate alkynes and are inactive in hydrogenation of alkenes. This work presents herein an efficient catalyst, consisting of in situ created PdS0.53 nanoparticles as the redox‐active sites inside the defect pores of metal–organic framework UiO‐66, which demonstrates very high alkene selectivity (up to 99.5%) in semihydrogenation of easily over‐hydrogenated terminal alkynes. In contrast to the traditional catalysts, strict control over the reaction time becomes the nonessential condition because the catalyst system is almost inactive in hydrogenation of alkenes. Therefore, this paradigm work provides a practically applicable pathway for the development of efficient catalysts with unique catalytic properties for selective semihydrogenation reactions.
Microwave Absorption of Organic Metal Halide Nanotubes
Authors: Lin Haoran , Green Michael , Xu Liang‐Jin , Chen Xiaobo , Ma Biwu 
Published: December 2019

AbstractOrganic metal halide hybrids have attracted tremendous research interests owing to their outstanding optical and electronic properties suitable for various applications, including photovoltaics, light‐emitting diodes, and photodetectors. Recently, the multifunctionality of this class of materials has been further explored beyond their optical and electronic properties. Here, for the first time the microwave electromagnetic properties of a 1D organic metal halide hybrid, (C6H13N4)3Pb2Br7, a single crystalline bulk assembly of organic metal halide nanotubes, are reported. Good microwave absorption performance with a large reflection loss value of −18.5 dB and a threshold bandwidth of 1.0 GHz is discovered for this material, suggesting its potential as a new microwave absorber. This work reveals a new functionality of organic metal halide hybrids and provides a new material class for microwave absorption application studies.
An Artificial Optoelectronic Synapse Based on a Photoelectric Memcapacitor
Authors: Zhao Lei , Fan Zhen , Cheng Shengliang , Hong Lanqing , Li Yongqiang , Tian Guo , Chen Deyang , Hou Zhipeng , Qin Minghui , Zeng Min , Lu Xubing , Zhou Guofu , Gao Xingsen , Liu Jun‐Ming 
Published: December 2019

AbstractThe rapid development of artificial intelligence technology has led to the urge for artificial optoelectronic synapses with visual perception and memory capabilities. A new type of artificial optoelectronic synapse, namely a photoelectric memcapacitor, is proposed and demonstrated. This photoelectric memcapacitor, with a planar Au/La1.875Sr0.125NiO4/Au metal–semiconductor–metal structure, displays a complementary optical and electrical modulation of capacitance, which can be attributed to the charge trapping/detrapping‐induced Schottky barrier variation. It further exhibits versatile synaptic functions, such as photonic potentiation/electric depression, paired‐pulse facilitation, short‐/long‐term memory, and “learning‐experience” behavior. Moreover, the photoplasticity of the memcapacitor can be modulated by varying the frequency of applied AC voltage, thus enabling self‐adaptive optical signal detection and mimicry of interest‐modulated human visual memory. Therefore, it represents a new paradigm for artificial optoelectronic synapses and opens up opportunities for developing low‐power humanoid optoelectronic devices.
Correlating Phase Behavior with Photophysical Properties in Mixed‐Cation Mixed‐Halide Perovskite Thin Films
Authors: Greenland Claire , Shnier Adam , Rajendran Sai K. , Smith Joel A. , Game Onkar S. , Wamwangi Daniel , Turnbull Graham A. , Samuel Ifor D. W. , Billing David G. , Lidzey David G. 
Published: December 2019

AbstractMixed cation perovskites currently achieve very promising efficiency and operational stability when used as the active semiconductor in thin‐film photovoltaic devices. However, an in‐depth understanding of the structural and photophysical properties that drive this enhanced performance is still lacking. Here the prototypical mixed‐cation mixed‐halide perovskite (FAPbI3)0.85(MAPbBr3)0.15 is explored, and temperature‐dependent X‐ray diffraction measurements that are correlated with steady state and time‐resolved photoluminescence data are presented. The measurements indicate that this material adopts a pseudocubic perovskite α phase at room temperature, with a transition to a pseudotetragonal β phase occurring at ≈260 K. It is found that the temperature dependence of the radiative recombination rates correlates with temperature‐dependent changes in the structural configuration, and observed phase transitions also mark changes in the gradient of the optical bandgap. The work illustrates that temperature‐dependent changes in the perovskite crystal structure alter the charge carrier recombination processes and photoluminescence properties within such hybrid organic–inorganic materials. The findings have significant implications for photovoltaic performance at different operating temperatures, as well as providing new insight on the effect of alloying cations and halides on the phase behavior of hybrid perovskite materials.
Manganese Oxide Modified Nickel Catalysts for Photothermal CO Hydrogenation to Light Olefins
Authors: Wang Yuanshen , Zhao Yufei , Liu Jinjia , Li Zhenhua , Waterhouse Geoffrey I. N. , Shi Run , Wen Xiaodong , Zhang Tierui 
Published: December 2019

AbstractNi‐based catalysts are traditionally considered unsuitable for the Fischer–Tropsch syntheses of olefins, due to the very strong hydrogenation ability of metallic Ni. Herein, this paradigm is challenged. A series of MnO supports nickel catalysts (denoted herein as Ni‐x) are fabricated by H2 reduction of a nickel‐manganese mixed metal oxide at temperatures (x) ranging from 250 to 600 °C. The Ni‐500 catalyst displays unprecedented performance for photothermal CO hydrogenation to olefins, with an olefin selectivity of 33.0% under ultraviolet–visible irradiation. High‐resolution transmission electron microscopy, X‐ray absorption spectroscopy (XAS), and X‐ray diffraction analyses reveal that the Ni‐x catalysts contain metallic Ni nanoparticles supported by MnO. X‐ray photoelectron spectroscopy and XAS establish that electron transfer from MnO to the Ni0 nanoparticles is responsible for modifying the electronic structure of nickel (creating Niδ− states), thereby shifting the CO hydrogenation selectivity toward light olefins. Further, density functional theory calculations show that this electron transfer lowers the adsorption energies of olefins on Ni surfaces, thus minimizing the undesirable deep hydrogenation reactions to higher alkanes. This study conclusively demonstrates that MnO‐modified Ni‐based catalyst systems can be highly selective for CO hydrogenation to light olefins.
Accurate Determination of the Minimum HOMO Offset for Efficient Charge Generation using Organic Semiconducting Alloys
Authors: Zhang Jianyun , Liu Wenrui , Zhou Guanqing , Yi Yuanping , Xu Shengjie , Liu Feng , Zhu Haiming , Zhu Xiaozhang 
Published: December 2019

AbstractCurrent research indicates that exciton dissociation into free charge carriers can be achieved in material combinations with the highest occupied molecular orbital (HOMO) offset lowered to 0 eV in non‐fullerene organic solar cells. However, the quantitative relationship between the HOMO offset and exciton dissociation has not been established because of the difficulty in achieving continuously tunable HOMO offsets. Here, the binary blends of PTQ10:ZITI‐S and PTQ10:ZITI‐N are combined to form the positive and negative HOMO offsets of 0.20 and −0.07 eV, respectively. While the PTQ10:ZITI‐S binary blend delivers a decent power conversion efficiency (PCE) of 10.69% with a short‐circuit current (Jsc) of 16.94 mA cm−2, the PTQ10:ZITI‐N with the negative offset shows a much lower PCE of 7.06% mainly because of the low Jsc of 12.03 mA cm−2. Because the tunable HOMO levels can be realized in organic semiconducting alloys based on ZITI‐N and ZITI‐S acceptors, the transformation of the HOMO energy offset from negative to positive values is achieved in the PTQ10:ZITIN:ZITI‐S ternary blends, delivering much‐improved PCEs up to 13.26% with a significant, 74% enhancement of Jsc to 20.93 mA cm−2. With detailed investigations, the study reveals that the minimum HOMO offset of ≈40 meV is required to achieve the most‐efficient exciton dissociation and photovoltaic performance.
meso‐(2‐Pyridyl)‐boron(III)‐subporphyrin: Perimeter Iridium(III) Coordination
Authors: Lavarda Giulia , Shimizu Daiki , Torres Tomás , Osuka Atsuhiro 
Published: December 2019

AbstractPeripherally metalated porphyrinoids are promising functional π‐systems displaying characteristic optical, electronic, and catalytic properties. In this work, 5‐(2‐pyridyl)‐ and 5,10,15‐tri(2‐pyridyl)‐BIII‐subporphyrins were prepared and used to produce cyclometalated subporphyrins by reactions with [Cp*IrCl2]2, which proceeded through an efficient C−H activation to give the corresponding mono‐ and tri‐IrIII complexes, respectively. While the mono‐IrIII complex was obtained as a diastereomeric mixture, a C3‐symmetric tri‐IrIII complex with the three Cp*‐units all at the concave side was predominantly obtained in a high yield of 90 %, which displays weak NIR phosphorescence even at room temperature in degassed CH2Cl2, differently from the mono‐IrIII complexes.
Performance‐Enhancing Approaches for PEDOT:PSS‐Si Hybrid Solar Cells
Authors: Sun Zhe , He Ya , Xiong Banglun , Chen Shanshan , Li Meng , Zhou Yongli , Zheng Yujie , Sun Kuan , Yang Changduk 
Published: December 2019

AbstractThe emerging energy crisis has focused significant worldwide attention on solar cells. Although crystalline silicon solar cells are currently widely used, their high cost limits the development of solar power generation. Consequently, hybrid solar cells are becoming increasingly important, especially organic‐Si hybrid solar cells (HSCs). Organic‐Si HSCs combine a mature technology and high efficiency with the low‐temperature manufacturing process and tunable optoelectronic properties of organic solar cells. The organic material can be P3HT, carbon nanotubes, graphene, and PEDOT:PSS. Here we review the performance of PEDOT:PSS/Si HSCs and methods for improving their efficiency, such as PEDOT:PSS modification, optimization of the trapping effect, passivation of the silicon surface, addition of an interface layer, improvement of a back contact, and optimization of the metal top electrode. This Review should help fill the gap in this area and provide perspectives for the future development of the PEDOT:PSS/Si HSCs.
Macroscopic Self‐Evolution of Dynamic Hydrogels to Create Hollow Interiors
Authors: Han Lu , Zheng Yijun , Luo Hao , Feng Jun , Engstler Roxanne , Xue Lulu , Jing Guangyin , Deng Xu , del Campo Aránzazu , Cui Jiaxi 
Published: December 2019

AbstractA solid‐to‐hollow evolution in macroscopic structures is challenging in synthetic materials. A fundamentally new strategy is reported for guiding macroscopic, unidirectional shape evolution of materials without compromising the material's integrity. This strategy is based on the creation of a field with a “swelling pole” and a “shrinking pole” to drive polymers to disassemble, migrate, and resettle in the targeted region. This concept is demonstrated using dynamic hydrogels containing anchored acrylic ligands and hydrophobic long alkyl chains. Adding water molecules and ferric ions (Fe3+) to induce a swelling–shrinking field transforms the hydrogels from solid to hollow. The strategy is versatile in the generation of various closed hollow objects (for example, spheres, helix tubes, and cubes with different diameters) for different applications.
The use of high‐flow nasal oxygen during airway management in a child with epidermolysis bullosa dystrophica and a difficult airway
Authors: Ng L. Y. , Chan A. K. M. , Lam T. W. Y. 
Published: December 2019

SummaryThe role of high‐flow nasal oxygen in paediatric anaesthesia has been emerging in recent years. However, literature regarding its benefits in paediatric difficult airway management is limited. In this case report, we describe the use of high‐flow nasal oxygen during airway management of a child with a difficult airway due to epidermolysis bullosa dystrophica in whom the use of a facemask would have been potentially harmful. Deep sedation was achieved with propofol and remifentanil while maintaining spontaneous breathing before flexible bronchoscopic tracheal intubation was attempted. However, on attempted tracheal intubation difficulty was encountered due to poor visualisation and contact bleeding. Tracheal intubation was eventually successful after converting to videolaryngoscopy. Oxygenation was maintained throughout the process despite deep sedation and a long procedure time. Moreover, no skin abrasions or mucosal injury resulted from the use of high‐flow nasal oxygen. We conclude that high‐flow nasal oxygen has a valuable role during airway management for a child with a predicted difficult airway when the use of a facemask would have been potentially harmful.
Effect of doping graphene oxide on the structure and properties of SiO2 based high emissivity coatings
Authors: Song Guangping , He Shifeng , He Fei , Yao Yongtao , Li Jianjun , Li Mingwei , He Xiaodong 
Published: December 2019

ABSTRACTHigh emissivity coatings have received a great attention due to their energy saving capability for using in spacecraft and industrial furnaces applications. In this study, a feasible spray deposition method was employed to prepare a high emissivity coating on Kovar alloy substrate with porous structure after heat treatment. Graphene oxide was used to dope coating to improve its emissivity. The emissivity enhancement mechanisms of the graphene oxide doped SiO2 coatings have been investigated. Results show that coating emissivity can be significantly improved (6.41 and 9.64% of coating emissivity at 500 and 800°C, respectively) by doping graphene oxide. Thus, this study proposed a feasible and effective method to prepare high emissivity coatings. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48794.
Hydrogen‐bonding assembly of heteropolyacid and poly(vinyl alcohol) for strong, flexible, and transparent UV‐protective films
Authors: Zhang Ziang , Chen Kui , Tang Qun , Li Heping , Zou Zhiming 
Published: December 2019

ABSTRACTAlthough many preparation approaches have been developed, it remains a huge challenge to achieve ultraviolet (UV)‐protection films that combine high transparency, excellent UV‐shielding, and mechanical properties. Herein, we demonstrate a facile and eco‐friendly process for fabricating strong, flexible, and transparent UV‐protective poly(vinyl alcohol) (PVA) films by exploiting silicomolybdic acid (SiMoA) as UV absorber and reinforcing phase. Fourier‐transform infrared analysis confirms the formation of strong hydrogen‐bonding interactions between PVA and SiMoA. The glass‐transition temperature, mechanical properties, and UV‐shielding stability of the UV‐protective PVA composite films obviously increase with increasing the content of SiMoA. By incorporation of only 2 wt % SiMoA, the UV‐protective PVA composite film can block more than 90% of UV light in the entire UV regions and retain high visible light transparency (up to 95%). Simultaneously, the UV‐protective PVA composite film presents excellent mechanical properties with a tensile strength of 65.2 MPa and an elongation at break of 172.6%, which are 72.0 and 69.5% higher than that of pristine PVA films. This work provides a simple but effective approach for creating strong, flexible, and transparent UV‐blocking polymeric materials via hydrogen‐bonding assembly, which are expected to have wide application prospects in UV‐protection field. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48813.
Physicochemical and antimicrobial properties of in situ crosslinked alginate/hydroxypropyl methylcellulose/ε‐polylysine films
Authors: Blachechen Tatiana Schafranski , Petri Denise Freitas Siqueira 
Published: December 2019

ABSTRACTIn the present study, in situ crosslinked films were easily prepared by the spray deposition of Phase A, composed by sodium alginate (Alg), hydroxypropyl methylcellulose (HPMC), ε‐polylysine (ε‐PL), and plasticizers, followed by the spray deposition of Phase B (Ca2+ ions) on polystyrene dishes. The effect of the amount of plasticizer, HPMC, and ε‐PL in Phase A on the films properties was explored in a set of 12 systems. Fourier transform infrared vibrational spectroscopy in the attenuated total reflectance mode revealed that plasticizers compete with Ca2+ ions for complexation with Alg. Films with high HPMC content and low content of plasticizer and ε‐PL presented the best mechanical properties. The best system presented Young modulus of 0.76 ± 0.10 GPa, water vapor transmission of 5.35 ± 0.28 mg cm−2 h−1, swelling ratio of 1374 ± 97%, 99.99% reduction against Gram‐negative Escherichia coli bacteria, and 99.9% reduction against Gram‐positive Staphylococcus aureus bacteria. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48832.
Input‐output finite‐time stability of fractional‐order switched singular continuous‐time systems
Authors: Feng Tian , Wu Baowei , Wang Yue‐E , Liu Lili 
Published: December 2019

AbstractThe input‐output finite‐time stability and stabilization of a class of fractional‐order switched singular continuous‐time systems with order 0<α<1 are studied in this paper. First, based on the average dwell time switching technique, by constructing multiple Lyapunov functions, the sufficient conditions of input‐output finite‐time stability for the considered systems are derived in the form of linear matrix inequalities (LMIs). Second, a suitable LMI‐based state feedback controller is designed. Finally, an illustrative example is presented to show the effectiveness of the proposed technique.