bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metallic 3D Random Nanocomposite Islands For Near‐Field Spatial Light Switching
Authors: Son Taehwang , Moon Gwiyeong , Lee Hongki , Kim Donghyun 
Published: March 2018

AbstractRandom nanocomposite islands have drawn significant interest for diverse applications due to extreme simplicity of fabricating nanoscale structures. In this paper, the near‐field characteristics of random nanoislands produced by spatial light switching are investigated, with light incidence switching among 14 incident channel modes. The results show that localized light fields are displaced from nanoislands almost linearly with the incident angle of channels. Also, light fields rotate in a manner aligned to the direction of light incidence. Ten‐channel spatial switching is found to provide coverage of near‐fields on the surface close to 90%. The numerical data are experimentally validated using fluorescent imaging and near‐field scanning optical microscopy. The results suggest the possibility of using random nanoislands for high performance imaging such as superresolution microscopy and molecular detection techniques.
Phonon‐Like Plasmonic Resonances in a Finite Number of Graphene Nanoribbons
Authors: Huang Lei , Liu Jianqiang , Deng Hongmei , Wu Shan 
Published: March 2018

AbstractGraphene plasmon polaritons excited in individual and periodic nanoribbons microstructures have attracted enormous attention in plasmonics due to their complicated edge effect and excellent tunability. As the distance between neighboring graphene nanoribbons becomes small enough, the strong coupling between the plasmons in individual nanoribbons produces collective oscillations of surface plasmons in a graphene nanoribbons array, the dispersion of which behaves as phonons in a solid, that is, the phonon‐like plasmonic resonance mode. In this paper, such a phonon‐like plasmonic resonance is theoretically demonstrated in a finite number of graphene nanoribbons deposited on a silicon substrate. Based on the classical LC circuit model, an analytical dispersion relation is obtained to explain the simulated results. Furthermore, an electrically controlled plasmonic switch is proposed with a high performance based on the plasmonic phonon‐like resonance theory. The work provides the building blocks to construct graphene plasmonic circuits for future compact optoelectronic devices.
Liquid Crystals for Superior Electro‐Optic Performance Display Device with Power‐Saving Mode
Authors: Kim MinSu , Jin Heui Seok , Lee Seung Jae , Shin Yun‐Ho , Ham Hyeong Gyun , Yang Deng‐Ke , Bos Philip J. , Lee Joong Hee , Lee Seung Hee 
Published: March 2018

AbstractAn advantageous factor for the technology of displays is low power consumption. For power‐saving, low‐frequency driving of liquid crystal displays (LCDs) is useful. However, an unacceptable performance drop, from image‐flickering, occurs due to occurrence of the flexoelectric effect. Here, based on close agreement between experimental and simulated results, a new electro‐optic mode with optimization of both electrode structures and physical properties of the liquid crystal materials is demonstrated. Although the calculated electro‐optic properties are obtained for particular simulation conditions, the achieved transmittance is exceptional for LCDs using a power‐saving mode, and can result in complete elimination of static and dynamic flickering. It is believed the result will pave the way toward successful design for low‐power consumption and high‐performance LCDs.
Luminescent Diiridium Complexes with Bridging Pyrazolates: Characterization and Fabrication of OLEDs Using Vacuum Thermal Deposition
Authors: Liao Jia‐Ling , Rajakannu Palanisamy , Gnanasekaran Premkumar , Tsai Shang‐Ru , Lin Chun‐Han , Liu Shih‐Hung , Chang Chih‐Hao , Lee Gene‐Hsiang , Chou Pi‐Tai , Chen Zhong‐Ning , Chi Yun 
Published: March 2018

AbstractA series of novel diiridium complexes (1–4) bearing both functional 2‐pyrazolyl‐6‐phenyl pyridine chelate and bidentate phenyl imidazolylidene chelate are synthesized, for which the pyrazolate fragment of the tridentate 2‐pyrazolyl‐6‐phenyl pyridine also behaves as the bridge to hold two iridium atoms in close vicinity. Their structure is unambiguously confirmed using X‐ray structure determination on the corresponding derivative 2a bearing 1,3‐bis(4‐fluorophenyl)‐1H‐Imidazolyl cyclometalate. Their photophysical and electrochemical properties are studied and further affirmed by the computational approaches. All these Ir(III) metal complexes 1–4 are very stable in both solution and solid film with near unity emission quantum efficiency. As opposed to most of diiridium complexes documented in literature, 1–4 are volatile and suitable for fabrication of organic light emitting diodes (OLEDs) under vacuum evaporation. The corresponding electroluminescent devices exhibit superior performance, among which external quantum efficiency of 27.6% using 2 as dopant stands for the record high of OLEDs using dinuclear Ir(III) complexes. They also offer a low roll‐off at high luminance, demonstrating their potential en route to high performance OLEDs.
Isothiocyanate Strategy for the Synthesis of Quaternary α‐Amino Acids Bearing a Spirocyclic Ring System
Authors: Frankowski Sebastian , Gajda Tadeusz , Albrecht Łukasz 
Published: March 2018

AbstractThis study demonstrates that isothiocyanates derived from α‐substituted α‐amino acids are useful building blocks in the heteroannulation reactions with electron‐deficient olefins. The developed strategy proceeds in a cascade manner and involves Michael addition followed by a cyclization via nucleophilic addition. Target, spirocyclic heterocycles bearing either a quaternary α‐amino acid moiety or α‐aminophosphonate group have been efficiently synthesized in very high yield (up to 99%) and with excellent stereocontrol. The usefulness of heterocycles obtained has been demonstrated in selected transformations.magnified image
Enantioselective Synthesis of trans‐Vicinal Diamines via Rhodium‐Catalyzed [2+2] Cycloaddition of Allenamides
Authors: Zheng Wei‐Feng , Sun Gui‐Jun , Chen Liang , Kang Qiang 
Published: March 2018

AbstractAn efficient protocol for the enantioselective Rh‐catalyzed intermolecular head‐to‐head [2+2] cycloaddition of allenamides was developed. A variety of enantio‐enriched cyclobutane‐1,2‐diamine derivatives were achieved in good yields with good to excellent enantioselectivities.magnified image
Lewis Acid‐Catalyzed Formal [3+3] Annulation of Propargylic Alcohols with 4‐Hydroxy‐2H‐chromen‐2‐ones
Authors: Han Ya‐Ping , Li Xue‐Song , Li Ming , Zhu Xin‐Yu , Liang Yong‐Min 
Published: March 2018

AbstractA Lewis acid‐catalyzed formal [3+3] cascade annulation strategy for the formation of diverse tricyclic compounds possessing functionalized pyrano[3,2‐c]chromen‐5(2H)‐one fragments has been developed using propargylic alcohols and 4‐hydroxy‐2H‐chromen‐2‐ones as the substrates. The protocol provides a one‐step, environmentally benign method of accessing a broad range of pyrano[3,2‐c]chromen‐5(2H)‐one derivatives in excellent yields under mild conditions and with good functional‐group tolerance. The method is effective on the gram scale, which highlights the inherent practicality of this synthetic transformation.magnified image
Application of 7‐Indolylmethanols in Catalytic Asymmetric Arylations with Tryptamines: Enantioselective Synthesis of 7‐indolylmethanes
Authors: Wang Hai‐Qing , Xu Meng‐Meng , Wan Ying , Mao Yu‐Jia , Mei Guang‐Jian , Shi Feng 
Published: March 2018

AbstractThe application of 7‐indolylmethanols in catalytic asymmetric reactions has been established via an enantioselective arylation reaction with tryptamines in the presence of chiral phosphoric acid, which afforded a series of structurally diversified chiral 7‐indolylmethanes in moderate to good yields and generally excellent enantioselectivities (23 examples, up to 92% ee). This reaction not only provides a useful strategy for the enantioselective synthesis of chiral 7‐indolylmethanes, but also represents a good example of 7‐indolylmethanol‐involved catalytic asymmetric reaction, which will greatly enrich the chemistry of indolylmethanols.magnified image
Fe‐catalyzed dithiane radical induced C−S bond activation−addition to α, β‐unsaturated ketones
Authors: Min Deng , Yuan Xinyu , Liu Teng , Liu Jian , Tang Shouchu 
Published: March 2018

AbstractAn efficient and clean strategy to construct organosulfur compounds has been developed via a Fe‐catalyzed dithiane C−S bond activation/addition process with α, β‐unsaturated ketones. This C−S activation protocol exhibits excellent reactivities, and up to 92% yield of the corresponding thioether‐thioester derivatives could be obtained under the mild conditions, allowing the ready preparation of a number of synthetically valuable S‐linked conjugates.magnified image
Highly Efficient Ammonia Synthesis Electrocatalyst: Single Ru Atom on Naturally Nanoporous Carbon Materials
Authors: Cao Yongyong , Gao Yijing , Zhou Hu , Chen Xianlang , Hu Hui , Deng Shengwei , Zhong Xing , Zhuang Guilin , Wang Jianguo 
Published: March 2018

AbstractStabilizing single‐atom metal catalysts with carbon materials and utilizing their synergistic effect remains challenging due to weak interactions between carbon‐based supports and metals. Density functional theory (DFT) calculations indicate that a single Ru atom was supported on a wide range of natural nanoporous carbon materials, including C2N, triazine‐C3N4 (T‐C3N4), and γ‐graphene. These carbon materials belong to a new generation of highly efficient electrocatalysts for the N2 reduction reaction (NRR) and are named Ru1@C2N, Ru1@T‐C3N4, and Ru1@γ‐graphyne, respectively. Ab initio molecular dynamic (AIMD) simulations show that a single Ru atom can be stably anchored in the nanopores of these carbon materials with strong cohesive energy. Compared with parallel adsorption configuration, the vertical adsorption configuration of N2 exhibits higher adsorption energy. The calculated Gibbs free energy reveals N2 reduction on the three catalysts via associative mechanisms. Despite the similar limiting potentials (−0.96, −0.94, and −0.98 V on Ru1@C2N, Ru1@T‐C3N4, and Ru1@γ‐graphynes, respectively), the limiting step differs, indicating the significant effects of carbon material substrates on electrochemical NRR. However, the competitive and efficient hydrogen evolution reaction (HER) changes the potential determining step and increases the overpotential for the electrochemical nitrogen reduction (NRR). This study provides insights for experimental synthesis of electrocatalysts for N2 reduction.
Antimicrobial activity of organic–inorganic hybrid films based on gelatin and organomodified silicones
Authors: Wojciechowska Patrycja , Tichoniuk Mariusz , Gwiazdowska Daniela , Maciejewski Hieronim , Nowicki Marek 
Published: March 2018

AbstractGelatin–siloxane hybrid films containing antimicrobial agents were prepared in the two‐step procedure. First, gelatin was chemically modified with organomodified silicones containing epoxy (S1) and both epoxy and fluoroalkyl groups (S2). Next, antimicrobial agents such as lysozyme, EDTA, and nisin, in various concentrations, were introduced into obtained hybrid solution, prior to solvent casting of the films. Antimicrobial activity of prepared samples, as well as neat gelatin and gelatin–siloxane hybrid as a reference, was investigated using a modified agar diffusion method against several bacterial strains (Aeromonas hydrophila, Bacillus subtilis, Escherichia coli) and opportunistic fungus (yeast species Candida albicans). Prepared gelatin–siloxane films were characterized using FT‐IR, thermal and SEM analysis. Mechanical properties and swelling behavior of the samples were also investigated. The influence of type and amount of organosilicon compound used for modification of gelatin, as well as type and concentration of applied active agent on antimicrobial activity, was determined. We observed higher antimicrobial activity for all synthesized gelatin–siloxane hybrids than for unmodified gelatin with lysozyme, nisin, and EDTA prepared as comparison. Moreover, samples obtained with siloxane containing fluoroalkyl groups (S2) showed higher resistance to microbial agents than hybrids with S1 siloxane. Hybrid films showed also better water stability than neat biopolymer.
Fever‐Inspired Immunotherapy Based on Photothermal CpG Nanotherapeutics: The Critical Role of Mild Heat in Regulating Tumor Microenvironment
Authors: Li Yan , He Lianghua , Dong Haiqing , Liu Yiqiong , Wang Kun , Li Ang , Ren Tianbin , Shi Donglu , Li Yongyong 
Published: March 2018

AbstractAlthough there have been more than 100 clinical trials, CpG‐based immunotherapy has been seriously hindered by complications in the immunosuppressive microenvironment of established tumors. Inspired by the decisive role of fever upon systemic immunity, a photothermal CpG nanotherapeutics (PCN) method with the capability to induce an immunofavorable tumor microenvironment by casting a fever‐relevant heat (43 °C) in the tumor region is developed. High‐throughput gene profile analysis identifies nine differentially expressed genes that are closely immune‐related upon mild heat, accompanied by IL‐6 upregulation, a pyrogenic cytokine usually found during fever. When treated with intratumor PCN injection enabling mild heating in the tumor region, the 4T1 tumor‐bearing mice exhibit significantly improved antitumor immune effects compared with the control group. Superb efficacy is evident from pronounced apoptotic cell death, activated innate immune cells, enhanced tumor perfusion, and intensified innate and adaptive immune responses. This work highlights the crucial role of mild heat in modulating the microenvironment in optimum for improved immunotherapy, by converting the tumor into an in situ vaccine.
Multidimensional Evolution of Carbon Structures Underpinned by Temperature‐Induced Intermediate of Chloride for Sodium‐Ion Batteries
Authors: Ge Peng , Hou Hongshuai , Cao Xiaoyu , Li Sijie , Zhao Ganggang , Guo Tianxiao , Wang Chao , Ji Xiaobo 
Published: March 2018

AbstractDifferent dimensions of carbon materials with various features have captured numerous interests due to their applications on the tremendous fields. Restricted by the raw materials and devices, the controlling of their morphology is a major challenge. Utilizing the catalytic features of the intermediates from the low‐cost salts and polymerization of 0D carbon quantum dots (CQDs), 0D CQDs are expected to self‐assemble into 1/2/3D carbon structures with the assistance of temperature‐induced intermediates (e.g., ZnO, Ni, and Cu) from the salts (ZnCl2, NiCl2, and CuCl). The formation mechanisms are illustrated as follows: 1) the “orient induction” to evoke “vine style” growth mechanism of ZnO; 2) the “dissolution–precipitation” of Ni; and 3) the “surface adsorption self‐limited” of Cu. Subsequently, the degree of graphitization, interlayer distance, and special surface area are investigated in detail. 1D structure from 700 °C as anode displays a high Na‐storage capacity of 301.2 mAh g−1 at 0.1 A g−1 after 200 cycles and 107 mAh g−1 at 5.0 A g−1 after 5000 cycles. Quantitative kinetics analysis confirms the fundamentals of the enhanced rate capacity and the potential region of Na‐insertion/extraction. This elaborate work opens up an avenue toward the design of carbon with multidimensions and in‐depth understanding of their sodium‐storage features.
High Electromagnetic Waves Absorbing Performance of a Multilayer‐Like Structure Absorber Containing Activated Carbon Hollow Porous Fibers–Carbon Nanotubes and Fe3O4Nanoparticles
Authors: Gao Xuehua , Wu Xiangyi , Qiu Jun 
Published: March 2018

AbstractCarbon nanotubes (CNTs) are grown on the surface of activated carbon hollow porous fibers (ACHFs) by chemical vapor deposition. A multilayer‐like structure absorber ACHFs–CNTs–Fe3O4is prepared when Fe3O4nanoparticles/epoxy resin are injected into the hollow structure of ACHFs. Microwave reflection loss, permittivity, and permeability of ACHFs–CNTs–Fe3O4in 2–18 GHz are measured. The results show that the minimum reflection loss of ACHFs–CNTs–Fe3O4has reached to −46.828 dB at 14.4 GHz with the thickness of 2.5 mm, and the bandwidth below −10 dB can be as broad as 7.2 GHz. A wide effective absorbing bandwidth can be 13.54 GHz with the variation of the sample thickness from 1.5 to 5.0 mm. The low minimum reflection loss may result from electromagnetic coupling effect of ACHFs, CNTs, and Fe3O4nanomagnetic particles. The broad absorbing bandwidth is ascribed to its special multilayer‐like structure.
Outstanding Comprehensive Performance of La(Fe, Si)13Hy/In Composite with Durable Service Life for Magnetic Refrigeration
Authors: Wang YiXu , Zhang Hu , Liu EnKe , Zhong XiChun , Tao Kun , Wu MeiLing , Xing ChengFen , Xiao YaNing , Liu Jian , Long Yi 
Published: March 2018

AbstractMagnetic refrigeration based on magnetocaloric effect (MCE) has become a promisingly alternative technology to the conventional vapor‐compression refrigeration. A great number of magnetic materials have been reported to exhibit larger MCE than that of the benchmark magnetic refrigerant Gd. However, these materials still have severe shortcomings on the “Non‐MCE” properties, such as hard preparation and fabrication, low thermal conductivity λ, and poor corrosion resistance and cycling stabilities, which hinder the practical application of these materials. In this paper, a novel La(Fe, Si)13Hy/In composite which is prepared by a readily available hot pressing method is demonstrated to exhibit an outstanding comprehensive performance with durable service life in various aspects. Noteworthily, the ΔSM does not decrease but increases with increasing nonmagnetic In metal. This advantageous anomaly is related to the strengthening of the first‐order itinerant electron metamagnetic transition induced by residual compression stress and surrounded constraints in the composite. The present results make La(Fe, Si)13Hy/In composite the most attractive alternative to Gd for magnetic refrigeration. Moreover, this work also provides a feasible way to solve the serious issues toward applications for La(Fe, Si)13‐based materials and other brittle magnetocaloric materials.
Mixed Domains Enhance Charge Generation and Extraction in Bulk‐Heterojunction Solar Cells with Small‐Molecule Donors
Authors: Alqahtani Obaid , Babics Maxime , Gorenflot Julien , Savikhin Victoria , Ferron Thomas , Balawi Ahmed H. , Paulke Andreas , Kan Zhipeng , Pope Michael , Clulow Andrew J. , Wolf Jannic , Burn Paul L. , Gentle Ian R. , Neher Dieter , Toney Michael F. , Laquai Frédéric , Beaujuge Pierre M. , Collins Brian A. 
Published: March 2018

AbstractThe interplay between nanomorphology and efficiency of polymer‐fullerene bulk‐heterojunction (BHJ) solar cells has been the subject of intense research, but the generality of these concepts for small‐molecule (SM) BHJs remains unclear. Here, the relation between performance; charge generation, recombination, and extraction dynamics; and nanomorphology achievable with two SM donors benzo[1,2‐b:4,5‐b]dithiophene‐pyrido[3,4‐b]‐pyrazine BDT(PPTh2)2, namely SM1 and SM2, differing by their side‐chains, are examined as a function of solution additive composition. The results show that the additive 1,8‐diiodooctane acts as a plasticizer in the blends, increases domain size, and promotes ordering/crystallinity. Surprisingly, the system with high domain purity (SM1) exhibits both poor exciton harvesting and severe charge trapping, alleviated only slightly with increased crystallinity. In contrast, the system consisting of mixed domains and lower crystallinity (SM2) shows both excellent exciton harvesting and low charge recombination losses. Importantly, the onset of large, pure crystallites in the latter (SM2) system reduces efficiency, pointing to possible differences in the ideal morphologies for SM‐based BHJ solar cells compared with polymer‐fullerene devices. In polymer‐based systems, tie chains between pure polymer crystals establish a continuous charge transport network, whereas SM‐based active layers may in some cases require mixed domains that enable both aggregation and charge percolation to the electrodes.
Boron Element Nanowires Electrode for Supercapacitors
Authors: Xue Qi , Gan Haibo , Huang Yan , Zhu Minshen , Pei Zengxia , Li Hongfei , Deng Shaozhi , Liu Fei , Zhi Chunyi 
Published: March 2018

AbstractThe pursuit of new categories of active materials as electrodes of supercapacitors remains a great challenge. Herein, for the first time, elemental boron as a superior electrode material of supercapacitors is reported, which exhibits significantly high capacitances and excellent rate performance in all alkaline, neutral, and acidic electrolytes. Notably, boron nanowire‐carbon fiber cloth (BNWs‐CFC) electrodes achieve a capacitance up to 42.8 mF cm−2 at a scan rate of 5 mV s−1 and 60.2 mF cm−2 at a current density of 0.2 mA cm−2 in the acidic electrolyte. Moreover, in all these three kinds of electrolytes, BNWs‐CFC electrodes demonstrate a decent cycling stability with >80% capacitance retention after 8000 charging/discharging cycles. The Dominating energy storage mechanism of BNWs in the different electrolytes is analyzed by looking into the kinetics of the electrochemical process. Subsequently, the BNWs‐CFC electrode is used to fabricate a flexible solid‐state supercapacitor, which reveals a specific capacitance up to 22.73 mF cm−2 and good mechanical performance after 1000 bending cycles. This study opens a new avenue to explore elemental boron‐based new nanomaterials for the application of energy storage with superior electrochemical performance.
Low‐Defect and Low‐Porosity Hard Carbon with High Coulombic Efficiency and High Capacity for Practical Sodium Ion Battery Anode
Authors: Xiao Lifen , Lu Haiyan , Fang Yongjin , Sushko Maria L. , Cao Yuliang , Ai Xinping , Yang Hanxi , Liu Jun 
Published: March 2018

AbstractHard carbon is regarded as the most promising anode material for commercialization of Na ion batteries because of its high capacity and low cost. At present, the practical utilization of hard carbon anodes is largely limited by the low initial Coulombic efficiency (ICE). Na ions have been found to adopt an adsorption–insertion storage mechanism. In this paper a systematic way to control the defect concentration and porosity of hard carbon with similar overall architectures is shown. This study elucidates that the defects in the graphite layers are directly related to the ICE as they would trap Na ions and create a repulsive electric field for other Na ions so as to shorten the low‐voltage intercalation capacity. The obtained low defect and porosity hard carbon electrode has achieved the highest ICE of 86.1% (94.5% for pure hard carbon material by subtracting that of the conductive carbon black), reversible capacity of 361 mA h g−1, and excellent cycle stability (93.4% of capacity retention over 100 cycles). This result sheds light on feasible design principles for high performance Na storage hard carbon: suitable carbon layer distance and defect free graphitic layers.