bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of the Surface Treatment on the Solution Coating of Single‐Crystalline Organic Thin‐Films
Authors: Janneck Robby , Heremans Paul , Genoe Jan , Rolin Cedric 
Published: April 2018

AbstractMeniscus‐guided solution‐coating techniques offer a great potential for the realization of high‐performance, single‐crystalline films of organic semiconductors over large areas. Such techniques rely on the creation of a shallow meniscus and a subsequent one‐directional coating. To achieve shallow meniscus fronts, the wetting behavior of the solvents on the substrate is crucial. Literature typically simply employs high surface energy substrates without investigating the exact impact of the surface treatment on film morphology and electrical characteristics. In this work, the zone‐casting of (2,7‐dioctyl[1]benzothieno[3,2‐b][1]benzothiophene) is systematically studied on various surface treatments with widely varying surface energies. A fundamental observation is that, as long as the solution wets the substrate with a low contact angle, the morphology of the coated thin films is independent from the surface treatment. Through a systematic characterization of the wetting envelope of the treated substrate, a predictive rule for the wetting behavior is defined that is more accurate than the quantification of substrate surface energy alone. Furthermore, thin films formed on different surfaces show similar mobilities, but can nevertheless display largely varying threshold voltages. Hence, such films are ideal to study the influence of different surface treatments on the electrical characteristics without interference from morphological effects.
3D Printing of Self‐Organizing Structural Elements for Advanced Functional Structures
Authors: Chi Jinchun , Zocca Andrea , Agea‐Blanco Boris , Melcher Jörg , Sparenberg Marc , Günster Jens 
Published: April 2018

AbstractA shape evolution approach based on the thermally activated self‐organization of 3D printed parts into minimal surface area structures is presented. With this strategy, the present communication opposes currently established additive manufacturing strategies aiming to stipulate each individual volumetric element (voxel) of a part. Instead, a 3D structure is roughly defined in a 3D printing process, with all its advantages, and an externally triggered self‐organization allows the formation of structural elements with a definition greatly exceeding the volumetric resolution of the printing process. For enabling the self‐organization of printed objects by viscous flow of material, functionally graded structures are printed as rigid frame and melting filler. This approach uniquely combines the freedom in design, provided by 3D printing, with the mathematical formulation of minimal surface structures and the knowledge of the physical potentials governing self‐organization, to overcome the paradigm which strictly correlates the geometrical definition of 3D printed parts to the volumetric resolution of the printing process. Moreover, a transient liquid phase allows local programming of functionalities, such as the alignment of functional particles, by means of electric or magnetic fields.
Printable Zn2GeO4 Microwires Based Flexible Photodetectors with Tunable Photoresponses
Authors: Chen Shuai , Lou Zheng , Chen Di , Shen Guozhen 
Published: April 2018

AbstractPrinted electronics have drawn considerable attention due to their unique features and broad applications in future portable and wearable electronic devices. Herein, a near‐field direct‐printing method is used to realize a precise manipulation of microwires in the level of the individual wire for depositioning in a desired position and direction. High‐performance flexible photodetectors are fabricated on printed aligned Zn2GeO4 microwires arrays, which show excellent photoresponse, stability, and uniformity toward UV light irradiation. Studies find that the photocurrents can be easily tuned by adjusting the number of printed microwires, enabling a potential application in printable imaging sensors. Patterned flexible photodetector arrays are also fabricated with a high sensitivity (≈4 × 103), precise manipulation, tunable photoresponses, and a good tolerance toward mechanical deformations. This work paves the way toward efficient fabrication of printable electronic device and facilitates their practical applications in future printed electronics, such as flexible and wearable functional devices, electronic textiles, transistors, and circuits.
Nonlinear Few‐Layer Antimonene‐Based All‐Optical Signal Processing: Ultrafast Optical Switching and High‐Speed Wavelength Conversion
Authors: Song Yufeng , Chen Yunxiang , Jiang Xiantao , Liang Weiyuan , Wang Ke , Liang Zhiming , Ge Yanqi , Zhang Feng , Wu Leiming , Zheng Jilin , Ji Jianhua , Zhang Han 
Published: April 2018

AbstractExploration of ultrastable 2D material‐based optical devices toward all‐optical signal processing is attracting rising interest. As a Group‐VA monoelemental 2D material, antimonene is becoming a promising nonlinear optical material owing to its outstanding optoelectronic advantages with long‐term stability. Herein, all‐optical signal processing based on the high optical nonlinearity of antimonene is first demonstrated. Few‐layer antimonene is fabricated and decorated on the microfiber as an optical device. The device can be applied as an all‐optical Kerr switcher with an extinction ratio as high as ≈12 dB and wavelength conversion of modulated high‐speed signals at a frequency up to 18 GHz. The findings indicate that such a few‐layer antimonene‐based photonics device is applicable in nonlinear optics, which can be potentially developed for the applications of next‐generation high‐speed optical communication.
Broadband Multifunctional Plasmonic Logic Gates
Authors: Sang Yungang , Wu Xiaojia , Raja Soniya S. , Wang Chun‐Yuan , Li Haozhi , Ding Yufeng , Liu Dahe , Zhou Jing , Ahn Hyeyoung , Gwo Shangjr , Shi Jinwei 
Published: April 2018

AbstractPlasmonic logic gates provide a promising platform to realize diffraction‐unlimited all‐optical logic circuits. However, previous plasmonic logic gates suffer from narrow bandwidth and high loss. Here, broadband plasmonic logic gates are proposed and demonstrated using a unique design based on curved silver gratings. These logic gates can maintain a high intensity contrast ratio (29 dB) under front optical illumination. And, the broadband feature is achieved due to the feature of zero optical path difference from different positions of the curved grating to the output port. All the seven fundamental logic gates are demonstrated. In addition, different types of logic gates can be realized using the same device configuration. The possibility of multifunctionality makes these logic gates easy for device fabrication and system integration.
Surface‐Mediated Alignment of Long Pitch Chiral Nematic Liquid Crystal Structures
Authors: Nys Inge , Beeckman Jeroen , Neyts Kristiaan 
Published: April 2018

AbstractChiral nematic liquid crystals are stimuli‐responsive soft materials that can self‐organize into complex chiral superstructures. Control and manipulation of the chiral ordering is essential in the development of functional electro‐optic devices. Here, the effect of surface topography is combined with an applied electric field to steer the directional growth of cholesteric fingers in a cell with thickness larger than the chiral pitch. The periodic e‐beam resist grating gives rise to micrometer‐scale periodic variations of the surface anchoring. By applying a voltage to the cell, controlled growth of cholesteric fingers along the surface grating is observed. The 2D liquid crystal director configuration at different voltages is identified by numerical simulations based on finite element Q‐tensor theory. The results demonstrate that samples with modulated surface chemistry lead to enhanced control over the formation of chiral structures. This can stimulate the development of electro‐optic devices (diffraction gratings, lasers, displays, etc.) with improved characteristics.
DBU‐Catalyzed Selective N‐Methylation and N‐Formylation of Amines with CO2 and Polymethylhydrosiloxane
Authors: Li Gang , Chen Jie , Zhu Dao‐Yong , Chen Ye , Xia Ji‐Bao 
Published: April 2018

AbstractWe describe herein an efficient organocatalytic system for the selective N‐methylation and N‐formylation of amines with carbon dioxide (CO2) as a sustainable C1 feedstock and polymethylhydrosiloxane (PMHS) as a cost‐effectvie reducing reagent. High‐yielding N‐methylation products are obtained with low catalyst loading (1%) of DBU. Selective N‐formylation of amines is achieved using the same catalytic system at a lower reaction temperature.magnified image
Sulfur‐Promoted Aminative Aromatization of 1,2,3,4‐Tetrahydrophenazines with Amines: Flexible Access to 1‐Aminophenazines
Authors: Nguyen Thanh Binh , Retailleau Pascal 
Published: April 2018

AbstractElemental sulfur was found to be an excellent reagent for promoting the aminative aromatization of 1,2,3,4‐tetrahydrophenazines with amines to provide a wide range of functionalized 1‐aminophenazines.magnified image
Regioselective Synthesis of Indene from 3‐Aryl Propargylic gem‐Dipivalates Catalyzed by N‐Heterocyclic Carbene Gold(I) Complexes
Authors: Hueber Damien , Teci Matthieu , Brenner Eric , Matt Dominique , Weibel Jean‐Marc , Pale Patrick , Blanc Aurélien 
Published: April 2018

Abstract1‐Aryl‐3,3‐bis(pivaloyloxy)propynes can be converted in good to high yields into either 1,3‐ or 1,2‐bis(pivaloyloxy)indenes, depending on the N‐heterocyclic carbene (NHC) gold(I) hexafluoroantimonate catalyst used. Almost exclusive formation of 1,3‐di(oxycarbonyl)indene derivatives was achieved with cationic gold complexes containing the embracing N,N′‐1,3‐bis(9‐butylfluorenyl)benzimidazolylidene ligand (nBuFNHC). The regioselective issue of the reaction was rationalized by the specific spatial distribution of the steric bulk in the nBuFNHC ligand. In contrast, only modest selectivities in favor of 1,2‐disubstituted indenes were observed with more classical NHC gold complexes, the best selectivity being then obtained with N,N′‐1,3‐bis(2,6‐diisopropylphenyl)‐4,5‐dihydroimidazolylidene gold chloride (SIPrAuCl) as precatalyst.magnified image
Highly Sensitive Sensing of NO and NO2 Gases by Monolayer C3N
Authors: Babar Vasudeo , Sharma Sitansh , Schwingenschlögl Udo 
Published: April 2018

AbstractUsing density functional theory with van der Waals dispersion correction, the adsorption behavior of common gaseous pollutants (CO, NO, NO2, and NH3) on monolayer C3N is investigated. The adsorption sites and energies, binding distances, charge transfers, and electronic band structures are calculated to understand the influence of the adsorbed molecules on the transport properties of monolayer C3N. The current–voltage characteristics are calculated using the nonequilibrium Green's function formalism. It turns out that all investigated molecules are physisorbed on monolayer C3N and that NO and NO2 gases can be sensed with high sensitivity. The recovery time of the sensor is found to be outstanding in the case of NO sensing (2.4 μs at room temperature) and competitive to other materials in the case of NO2 sensing.
Multicolor Electrochromic Fibers with Helix‐Patterned Electrodes
Authors: Zhou Yang , Fang Jian , Wang Hongxia , Zhou Hua , Yan Guilong , Zhao Yan , Dai Liming , Lin Tong 
Published: April 2018

AbstractWearable electrochromic devices with a multiple color changing effect have shown great potential for applications in the fields of displaying, decoration, safety warning, and sensors. However, limited attention is paid toward the preparation of multicolor electrochromic fiber devices. In this study, a set of electrochromic fibers which can change their color between dark red, green, and gold is prepared. The fiber devices are prepared by forming dual helix metal electrodes along a plastic fiber substrate and by subsequently depositing tungsten oxide and poly(3‐methylthiophene) separately on the two electrodes. A solid electrolyte LiClO4/poly(methyl methacrylate) is used so the entire device is in the form of freestanding fiber. The reversible electrochromism is driven by a voltage between −1.5 and +1.5 V. It shows high coloration efficiency (77.82 for WO3 and 54.41 cm2 C−1 for poly(3‐methylthiophene)) and fast response (up to 5 s). The distributions of electrical potential and lithium ion on the device are analyzed by a finite element method. This study may provide a novel method to construct multifunctional fiber electronics.
Full‐Spectrum Liquid‐Junction Quantum Dot–Sensitized Solar Cells by Integrating Surface Plasmon–Enhanced Electrocatalysis
Authors: Wang Feifan , Wang Hongju , Liu Xingyi , Wu Dapeng , Jiang Kai , Li Qi , Xu Dongsheng 
Published: April 2018

AbstractFull‐spectrum solar energy utilization is the ultimate goal of high‐performance photovoltaic devices. However, the present approaches to enhance sunlight harvesting in the cost‐effective quantum dot–sensitized solar cells mainly focus on the use of high‐frequency photons with the long‐wavelength sunlight being left behind. Here, a full‐spectrum solar cell architecture is proposed and the near‐infrared light–enhanced cell performance is demonstrated with a plasmonic and electrocatalytic dual‐function CuS nanostructure electrode. In the CdS/CdSe quantum dot–sensitized solar cells, an enhancement factor as high as 15% in power conversion efficiency is obtained for the device with near‐infrared part of 1‐sun light irradiating from the counter electrode side and ultraviolet–visible part incidence from the photoanode side. Electrochemical characterizations show that the enhanced electrocatalytic activity toward polysulfide reduction is attributed to the better device performance. This may be due to the plasmon‐induced photothermal effect and interfacial energy transfer from the counter electrode under the near‐infrared light, which accelerate the preceding chemical reactions for polysulfide reduction and improve the charge transfer at the electrode–electrolyte interface. This strategy provides an alternative way to achieve a full‐spectrum liquid‐junction solar cell via the integration of plasmon‐enhanced electrocatalysis into photovoltaics.
Exploring Inorganic Binary Alkaline Halide to Passivate Defects in Low‐Temperature‐Processed Planar‐Structure Hybrid Perovskite Solar Cells
Authors: Liu Xu , Zhang Yuanfang , Shi Lei , Liu Ziheng , Huang Jialiang , Yun Jae Sung , Zeng Yiyu , Pu Aobo , Sun Kaiwen , Hameiri Ziv , Stride John A. , Seidel Jan , Green Martin A. , Hao Xiaojing 
Published: April 2018

AbstractPlanar perovskite solar cells obtained by low‐temperature solution processing are of great promise, given a high compatibility with flexible substrates and perovskite‐based tandem devices, whilst benefitting from relatively simple manufacturing methods. However, ionic defects at surfaces usually cause detrimental carrier recombination, which links to one of dominant losses in device performance, slow transient responses, and notorious hysteresis. Here, it is shown that several different types of ionic defects can be simultaneously passivated by simple inorganic binary alkaline halide salts with their cations and anions. Compared to previous literature reports, this work demonstrates a promising passivation technology for perovskite solar cells. The efficient defect passivation significantly suppresses the recombination at the SnO2/perovskite interface, contributing to an increase in the open‐circuit voltage, the fast response of steady‐state efficiency, and the elimination of hysteresis. By this strong leveraging of multiple‐element passivation, low‐temperature‐processed, planar‐structured perovskite solar cells of 20.5% efficiencies, having negligible hysteresis, are obtained. Moreover, this defect‐passivation enhances the stability of solar cells with efficiency beyond 20%, retaining 90% of their initial performance after 30 d. This approach aims at developing the concept of defect engineering, which can be expanded to multiple‐element passivation from monoelement counterparts using simple and low‐cost inorganic materials.
Impact of Early Educational Intervention on Coding for First‐year Emergency Medicine Residents
Authors: Bang Sunny , Bahl Amit 
Published: April 2018

AbstractObjectivesCoding of a medical visit is based on provider documentation in the medical record; the documentation should reflect the level of care that was provided. To maximize coding and subsequent billing, providers must complete various components of the record to best convey the complexity of the case. Little education is provided to resident physicians regarding appropriate documentation practices, and studies suggest a need for improved education in this area. The primary goal of this study is to determine if implementing an early educational intervention will improve billing and coding.MethodsThis was a randomized, prospective controlled study in an academic Level I emergency department (ED). Interns without prior experience in billing and coding were eligible participants. Participants in the intervention group each received an interactive lecture on coding, evaluation and management (E/M) levels, and documentation macros, prior to their first ED rotation at the base hospital. A pocket card with E/M level requirements was given as a resource. Biweekly feedback was given to the residents to address any patterns of mistakes. The number of charts for each E/M level was collected from both groups, which were converted to relative value units (RVUs). A multivariate analysis using multivariate linear regressions controlling for age, sex of patient, admission rate, and month of encounter was used to statistically evaluate billing outcomes.ResultsThe mean RVUs per hour and encounter in the intervention group were, respectively, 3.52 and 3.84 while in the control group they were, respectively, 3.36 and 3.72 (p = 0.0112). Intervention group encounters had 27% greater odds (odds ratio = 1.27) of having a level 5 chart compared to the control group (p = 0.0025).ConclusionThe focused longitudinal educational interventions resulted in improved billing performances, reflected by better documentation, in the intervention group versus the control group.
Expert consensus on the assessment and treatment of chronic constipation in the elderly
Authors: Zheng Songbai , Yao Jianfeng ,   the Chinese Geriatric Society, Editorial Board of Chinese Journal of Geriatrics
Published: April 2018

AbstractIt is of significant importance to scientifically assess and efficiently address chronic constipation in the elderly population. Therefore, organizing some domestic experts of geriatrics and gastroenterology, we have formulated this consensus to reference for clinical staff.
Scaling relationships and vessel packing in petioles
Authors: Ray Dustin M. , Jones Cynthia S. 
Published: April 2018

Premise of the StudyWhile tradeoffs among mechanical and conductive functions have been well investigated in woody stems, these tradeoffs are relatively unexplored in petioles, the structural link between stems and laminas. We investigated size‐independent scaling relationships between cross‐sectional areas of structural and vascular tissues, relationships between tissue areas of xylem and phloem, vessel packing within xylem, and scaling of vascular and structural tissues with lamina traits.MethodsWe examined allometric relationships among petiole tissues and as a function of lamina and petiole size variation on eleven species of Pelargonium. From transverse sections of methacrylate‐embedded tissue, we measured the cross‐sectional areas of all tissues within the petiole and vessel lumen, and cell wall areas of each vessel. Allometric scaling relationships were analyzed using standardized major axis regressions.Key ResultsPelargonium petiole vessels were packed as predicted by Sperry's packing rule for woody stems. In contrast to woody stems, there was no evidence of a tradeoff between vessel area and fiber area. Within cross‐sections, more xylem was produced than phloem. Among bundles, xylem and phloem scaling relationships varied with bundle position. Except for lamina dry mass and petiole fiber cross‐sectional area, petiole and lamina traits were independent.ConclusionsPetioles share vascular tissue traits with stems despite derivation from leaf primordia. We did not find evidence for a tradeoff between structural and vascular tissues, in part because fibers occur outside the xylem. We propose this separation of conduction and support underlies observed developmental and evolutionary plasticity in petioles.
Intercepted Meyer–Schuster Rearrangements in Organic Synthesis
Authors: Roy Debayan , Tharra Prabhakararao , Baire Beeraiah 
Published: April 2018

AbstractThe Meyer–Schuster rearrangement of propargylic alcohols is a transformation in organic synthesis known for almost a century. The products of this reaction—α,β‐enones and their α‐functionalized units—are highly important functional groups for various synthetic transformations. Two modifications of this classical reaction, which involves interception of the intermediate allenol (or its equivalent) by either electrophiles or nucleophiles, have attracted the attention of synthetic organic chemists. This Focus Review provides a detailed description of the development of these two strategies.
Asymmetric Organocatalytic Electrophilic Heterofunctionalization of Oxindoles
Authors: Freckleton Megan , Baeza Alejandro , Benavent Llorenç , Chinchilla Rafael 
Published: April 2018

AbstractThe asymmetric synthesis of 3‐substituted oxindoles is a topic of considerable importance because these functionalized heterocycles are found in many natural products and drugs. In the last decade, significant advances have been made towards the asymmetric synthesis of 3‐heteroatom‐substituted oxindoles as a result of major improvements in asymmetric organocatalysis. This review will focus on the different types of asymmetric electrophilic organocatalyzed reactions, including the amination, halogenation, hydroxylation, and sulfenylation of oxindoles to form their enantioenriched 3‐heterosubstituted derivatives.
A Concerted Catalytic System for Sonogashira Coupling Reactions: Combination of N‐Heterocyclic Carbene Palladium and Copper Complexes
Authors: Shen Ancheng , Wu Zhen , Fang Yue , Yang Jinming , Zhu Haibo , Tu Tao 
Published: April 2018

AbstractRobust acenaphthoimidazolylidene palladium complexes have been demonstrated as highly efficient and general catalysts for Sonogashira cross‐coupling reactions in excellent yields even at 0.01 mol % catalyst loadings in combination with 1 mol % IPr–Cu under mild reaction conditions. The outcomes highlight that, along with the steric bulky aspects, σ‐donor properties of the NHC ligands are also crucial to accelerate the transformations.
Photoredox‐Mediated Minisci Alkylation of N‐Heteroarenes using Carboxylic Acids and Hypervalent Iodine
Authors: Wang Junhua , Li Guo‐Xing , He Gang , Chen Gong 
Published: April 2018

AbstractA new protocol of photoredox‐mediated Minisci alkylation of N‐heteroarenes with aliphatic carboxylic acids has been developed. Using Ru(bpy)3Cl2 as photocatalyst and acetoxybenziodoxole (BI–OAc) as oxidant, a variety of primary, secondary and tertiary alkyl groups can be efficiently incorporated into various electron‐deficient N‐heteroarenes. This protocol demonstrated excellent substrate scope and good functional group tolerance and can be applied to late‐stage functionalization of complex molecules.