bluuebunny/crossref_metadata_2025_split huggingface dataset:
Droplet Microarrays: From Surface Patterning to High‐Throughput Applications
Authors: Feng Wenqian , Ueda Erica , Levkin Pavel A. 
Published: March 2018

AbstractHigh‐throughput screening of live cells and chemical reactions in isolated droplets is an important and growing method in areas ranging from studies of gene functions and the search for new drug candidates, to performing combinatorial chemical reactions. Compared with microfluidics and well plates, the facile fabrication, high density, and open structure endow droplet microarrays on planar surfaces with great potential in the development of next‐generation miniaturized platforms for high‐throughput applications. Surfaces with special wettability have served as substrates to generate and/or address droplets microarrays. Here, the formation of droplet microarrays with designed geometry on chemically prepatterned surfaces is briefly described and some of the newer and emerging applications of these microarrays that are currently being explored are highlighted. Next, some of the available technologies used to add (bio‐)chemical libraries to each droplet in parallel are introduced. Current challenges and future prospects that would benefit from using such droplet microarrays are also discussed.
Reconfigurable Printed Liquids
Authors: Forth Joe , Liu Xubo , Hasnain Jaffar , Toor Anju , Miszta Karol , Shi Shaowei , Geissler Phillip L. , Emrick Todd , Helms Brett A. , Russell Thomas P. 
Published: March 2018

AbstractLiquids lack the spatial order required for advanced functionality. Interfacial assemblies of colloids, however, can be used to shape liquids into complex, 3D objects, simultaneously forming 2D layers with novel magnetic, plasmonic, or structural properties. Fully exploiting all‐liquid systems that are structured by their interfaces would create a new class of biomimetic, reconfigurable, and responsive materials. Here, printed constructs of water in oil are presented. Both form and function are given to the system by the assembly and jamming of nanoparticle surfactants, formed from the interfacial interaction of nanoparticles and amphiphilic polymers that bear complementary functional groups. These yield dissipative constructs that exhibit a compartmentalized response to chemical cues. Potential applications include biphasic reaction vessels, liquid electronics, novel media for the encapsulation of cells and active matter, and dynamic constructs that both alter, and are altered by, their external environment.
Textile Display for Electronic and Brain‐Interfaced Communications
Authors: Zhang Zhitao , Cui Liyuan , Shi Xiang , Tian Xiaochaoran , Wang Dongping , Gu Chunni , Chen Er , Cheng Xunliang , Xu Yifan , Hu Yajie , Zhang Jiayi , Zhou Lei , Fong Hon Hang , Ma Pibo , Jiang Gaoming , Sun Xuemei , Zhang Bo , Peng Huisheng 
Published: March 2018

AbstractTextile displays are poised to revolutionize current electronic devices, and reshape the future of electronics and related fields such as biomedicine and soft robotics. However, they remain unavailable due to the difficulty of directly constructing electroluminescent devices onto the textile‐like substrate to really display desired programmable patterns. Here, a novel textile display is developed from continuous electroluminescent fibers made by a one‐step extrusion process. The resulting displaying textile is flexible, stretchable, three‐dimensionally twistable, conformable to arbitrarily curved skins, and breathable, and can dynamically display a series of desired patterns, making it useful for bioinspired electronics, soft robotics, and electroluminescent skins, among other applications. It is demonstrated that these displaying textiles can also communicate with a computer and mouse brain for smart display and camouflage applications. This work may open up a new direction for the integration of wearable electroluminescent devices with the human body, providing new and promising communication platforms.
Interfacial Self‐Assembly of Colloidal Nanoparticles in Dual‐Droplet Inkjet Printing
Authors: Al‐Milaji Karam Nashwan , Secondo Ray Richard , Ng Tse Nga , Kinsey Nathaniel , Zhao Hong 
Published: March 2018

AbstractThe well‐known coffee‐ring effect causes colloidal particles to convectively transport toward the contact line of an inkjet droplet leading to a nonuniform deposition of the colloidal particles. In this work, the self‐assembly of colloidal particles in a dual‐droplet inkjet printing configuration to produce a nearly monolayer closely packed deposition of colloidal particles that exhibits a colorful reflection are demonstrated. By controlling the ink surface tensions and jetting parameters, the wetting droplets (the second droplet) containing colloidal polystyrene (PS) nanoparticles quickly spread over the supporting droplets (the first droplet) upon impact. The well‐ordered deposition is achieved by tuning the solvent composition of the wetting droplets and functionalization of the PS nanoparticles to encourage a network formation among the colloidal particles at the air–droplet interface. The underlying self‐assembly mechanism is insensitive to substrates and can be applied to many other material/substrate combinations. Finally, the origin of the color generation is highlighted, and the potential of the dual‐droplet inkjet printing process is discussed for fabrication of optical devices.
Temperature‐Induced Atomic Reconstruction At Au/MgAl2O4 Interfaces
Authors: Liu Fang , Xie Dong Yue , Bugnet Matthieu , Majdi Tahereh , Preston John S. , Wang Jian , Zhu Guo‐zhen 
Published: March 2018

AbstractThe metal–oxide interaction, associated with intermingling delocalization of bonding electrons in metals and ionic bonds in oxides, may cause reconstruction of interface structure and accordingly affect physical properties of heterogeneous materials. This Communication reports reconstructions of (111) interface between gold and magnesium aluminate spinel according to experimental observation and theoretical prediction. Three interfacial structures are evidenced with respect to the arrangement of gold atoms: perfect Au (111) interface, atoms missing in the first Au (111) plane, and atoms mixing in the two adjacent atomic planes. Such atomic arrangements in the reconstructed interfaces are similar to those of metal cations in the spinel lattice, thus providing new insights into the chemistry and structure of metal–oxide interfaces and highlighting new pathways toward metal–oxide interface engineering.
Thermal Conductivity Reduction at Inorganic–Organic Interfaces: From Regular Superlattices to Irregular Gradient Layer Sequences
Authors: Krahl Fabian , Giri Ashutosh , Tomko John A. , Tynell Tommi , Hopkins Patrick E. , Karppinen Maarit 
Published: March 2018

AbstractNanoscale superlattice structures are known to significantly suppress the thermal conductivity in thin films due to phonon scattering at the interfaces of the mutually different layers. Here it is demonstrated that in addition to the number of interfaces, their spacing within the film can lead to a reduction in thermal conductivity. The proof‐of‐concept data are for ZnO/benzene thin films fabricated through sequential gas‐surface reactions in atomic/molecular layer precision using the atomic/molecular layer deposition technique. In comparison to similarly constructed regular superlattice thin films, thermal conductivity values that are of the same magnitude, or even lower, are achieved for hybrid ZnO/benzene thin films in which the inorganic and organic layers are arranged in a more irregular manner to form various gradient patterns.
Luminescence in 2D Materials and van der Waals Heterostructures
Authors: Jie Wenjing , Yang Zhibin , Bai Gongxun , Hao Jianhua 
Published: March 2018

AbstractDue to the isolation and fabrication of a rapidly increasing number of 2D materials, extensive attention is drawn to investigate 2D materials for scientific and technological studies as well as potential applications. In recent years, a series of significant and fascinating properties have been found and further modified in graphene and graphene‐like 2D layered materials. Among them, luminescence is one of the important investigation aspects, which is relevant to the unique structural, carrier transport, photonic, and optoelectronic properties of 2D materials. Herein, a general overview of recent advances of luminescence in 2D systems, including 2D materials and van der Waals heterostructures, is given. This review article provides an insight into the mechanism of luminescence and the luminescent characterizations and performance as well as the methods employed to modulate the luminescence behaviors of 2D systems. A number of recent works are introduced to specifically describe the new developments of photoluminescence, electroluminescence, and nonlinear optics in 2D materials. Then, the applications of luminescence in 2D systems are discussed in terms of optoelectronics and biological fields. By summarizing the importance of luminescence in 2D materials and van der Waals heterostructures, the challenges and opportunities for future investigation and applications are highlighted.
Access to Amidines and Arylbenzimidazoles: Zinc‐Promoted Rearrangement of Oxime Acetates
Authors: Zhu Zhongzhi , Cen Jinghe , Tang Xiaodong , Li Jianxiao , Wu Wanqing , Jiang Huanfeng 
Published: March 2018

AbstractAn efficient and straightforward zinc‐promoted rearrangement of oxime acetates with arylamines for the synthesis of amidines has been developed under mild conditions. This process involves N−O/C−C bond cleavages and C−C/C−N bond formations. Various oxime acetates and arylamines are suitable for this transformation. Furthermore, diverse arylbenzimidazoles could also be prepared through simple one‐pot procedure.magnified image
Asymmetric Nazarov Cyclizations Catalyzed by Chiral‐at‐Metal Complexes
Authors: Mietke Thomas , Cruchter Thomas , Larionov Vladimir A. , Faber Tabea , Harms Klaus , Meggers Eric 
Published: March 2018

AbstractThe application of Lewis acidic chiral‐at‐metal complexes of iridium(III) and rhodium(III) as catalysts for the asymmetric polarized Nazarov cyclization of dihydropyran‐ and indole‐functionalized α‐unsaturated β‐ketoesters is reported (overall 24 examples). For both substrate classes, catalyst loadings of 2 mol% were found to be sufficient for achieving high yields and high stereoselectivities. The cyclized dihydropyran products were isolated in 85–98% yield, with 89%–>99% ee, and trans/cis ratios of 15:1–50:1 (9 examples). The cyclized indole products were typically isolated in more than 70% yield and in up to 93% yield, typically with more than 90% ee and in up to 97% ee, and trans/cis ratios of 12:1–28:1 (15 examples).magnified image
Enantioselective Construction of Spiro Thiazol‐4‐one Derivatives with Multiple Stereocenters via an Organocatalyzed Multicomponent Cascade Reaction
Authors: Xiao Yuanyuan , Jiang Rongrong , Wang Youming , Zhou Zhenghong 
Published: March 2018

AbstractWe have developed an organocatalyzed asymmetric three‐component reaction of thiazol‐4‐ones, acrolein and nitroolefins, which provides an efficient approach to access optically active spiro thiazol‐4‐ones. Under the catalysis of a bifunctional squaramide derived from L‐tert‐leucine, the reactions of a wide range of thiazol‐4‐ones, acrolein and nitroolefins took place smoothly to generate the corresponding spirothiazolone derivatives bearing four contiguous stereogenic centers in good yields with high levels of enantioselectivity. The title chiral spirothiazolones were obtained as a pair of separable epimers, which are formed through a double Michael addition followed by a Henry process.magnified image
PhIO/Et3N ⋅ 3HF‐Mediated Formation of Fluorinated 2H‐Azirines via Domino Fluorination/Azirination Reaction of Enamines
Authors: Zhang Yong , Zhao Xiaoyuan , Zhuang Chen , Wang Senlin , Zhang‐Negrerie Daisy , Du Yunfei 
Published: March 2018

AbstractA variety of enamine carboxylic esters and enaminones were converted to the biologically interesting fluorinated 2H‐azirines through reactions with PhIF2 generated in situ by PhIO and Et3N ⋅ 3HF in 1,2‐dichroloethane, which features the hypervalent iodine reagents‐mediated introduction of fluorine atom and formation of the 2H‐azirine skeleton under metal‐free conditions. The domino reaction is postulated to proceed via a PhIF2‐mediated oxidative fluorination and a subsequent azirination of the fluorinated enamine intermediates.magnified image
Direct Aryl‐Aryl Coupling without Pre‐Functionalization Enabled by Excessive Oxidation of Two‐Electron Ag(I)/Ag(III) Catalyst
Authors: Singh Ajay K. , Kim Min‐Gyu , Lee Hyune‐Jea , Singh Rakhi , Cho Seung Hwan , Kim Dong‐Pyo 
Published: March 2018

AbstractReported herein is a catalytic platform for formation of unsymmetrical biaryls by the coupling between inert Csp2−CH3 and Csp2−H via a tandem catalytic strategy. The platform utilizes traditional AgNO3 catalyst and excess amount of K2S2O8 oxidant. The excessive oxidant present converts the traditional one‐electron Ag(I)/Ag(II) chemistry to two‐electron Ag(I)/Ag(III) one, enabling one‐pot synthesis of aryl‐aryl scaffolds by using unactivated cheap commodity chemicals.magnified image
Origin of Temperature‐Dependent Ferroelectricity in Si‐Doped HfO2
Authors: Park Min Hyuk , Chung Ching‐Chang , Schenk Tony , Richter Claudia , Hoffmann Michael , Wirth Steffen , Jones Jacob L. , Mikolajick Thomas , Schroeder Uwe 
Published: March 2018

AbstractThe structural origin of the temperature‐dependent ferroelectricity in Si‐doped HfO2 thin films is systematically examined. From temperature‐dependent polarization‐electric field measurements, it is shown that remanent polarization increases with decreasing temperature. Concurrently, grazing incidence X‐ray diffraction shows an increase in the orthorhombic phase fraction with decreasing temperature. The temperature‐dependent evolution of structural and ferroelectric properties is believed to be highly promising for the electrocaloric cooling application. Magnetization measurements do not provide any indication for a change of magnetization within the temperature range for the strong crystalline phase transition, suggesting that magnetic and structural properties are comparatively decoupled. The results are believed to provide the first direct proof of the strongly coupled evolution of structural and electrical properties with varying temperature in fluorite oxide ferroelectrics.
Flexible, Scalable, and Highly Conductive Garnet‐Polymer Solid Electrolyte Templated by Bacterial Cellulose
Authors: Xie Hua , Yang Chunpeng , Fu Kun (Kelvin) , Yao Yonggang , Jiang Feng , Hitz Emily , Liu Boyang , Wang Sha , Hu Liangbing 
Published: March 2018

AbstractSolid‐state electrolytes are a promising candidate for the next‐generation lithium‐ion battery, as they have the advantages of eliminating the leakage hazard of liquid solvent and elevating stability. However, inherent limitations such as the low ionic conductivity of solid polymer electrolytes and the high brittleness of inorganic ceramic electrolytes severally impede their practical application. Here, an inexpensive, facile, and scalable strategy to fabricate a hybrid Li7La3Zr2O12 (LLZO) and poly(ethylene oxide)‐based electrolyte by exploiting bacterial cellulose as a template is reported. The well‐organized LLZO network significantly enhances the ionic conductivity by extending long transport pathways for Li ions, exhibiting an elevated conductivity of 1.12 × 10−4 S cm−1. In addition, the hybrid electrolyte presents a structural flexibility, with minor impedance increase after bending. The facile and applicable approach establishes new principles for the strategy of designing scalable and flexible hybrid polymer electrolytes that can be utilized for high‐energy‐density batteries.
Examining the relationship between vertical coordination strategies and technical efficiency: Evidence from the Brazilian ethanol industry
Authors: Sant'Anna Ana Claudia , Bergtold Jason S. , Shanoyan Aleksan , Granco Gabriel , Caldas Marcellus M. 
Published: March 2018

AbstractThe sugarcane industry in Brazil, one of the world's leading producers of ethanol and sugar, is undergoing significant changes driven by geographic expansion and technological innovations. These changes are forcing sugarcane producers and processors, to re‐evaluate their vertical coordination and growth strategies. This paper presents an empirical analysis of the relationship between the vertical coordination strategies at the production‐processing interface of the Brazilian ethanol supply chain and the technical efficiency of the mills. It utilizes data envelopment analysis and a Tobit censored model in combination with unique data on 204 mills that account for around half of Brazil's sugar and ethanol production. Results indicate that vertical integration and the location of the mill have a statistically significant impact on efficiency. The findings show that the technical efficiency is not the main driver of vertical integration implying that such decisions are primarily motivated by strategic considerations. The mills are likely to forgo gains in technical efficiency in exchange for improving their strategic position through vertical integration. These findings shed light on the underlying motivation for the observed level of vertical integration that accompanies the expansion of the Brazilian sugarcane industry. [EconLit citations: L22, Q12, Q16].
Trait differences in responses to arbuscular mycorrhizal fungi are stronger and more consistent than fixed differences among populations of Asclepias speciosa
Authors: Waller Lauren P. , Hahn Philip G. , Maron John L. , Lekberg Ylva 
Published: March 2018

Premise of the StudyArbuscular mycorrhizal (AM) fungi can promote plant growth and reproduction, but other plant physiological traits or traits that provide defense against herbivores can also be affected by AM fungi. However, whether responses of different traits to AM fungi are correlated and whether these relationships vary among plants from different populations are unresolved.MethodsIn a common garden experiment, we grew Asclepias speciosa plants from seed collected from populations found along an environmental gradient with and without AM fungi to assess whether the responses of six growth and defense traits to AM fungi are correlated.Key ResultsAlthough there was strong genetic differentiation in mean trait values among populations, AM fungi consistently increased expression of most growth and defense traits across all populations. Responses of biomass and root to shoot ratio to AM fungi were positively correlated, suggesting that plants that are more responsive to AM fungi allocated more biomass belowground. Responses of biomass and trichome density to AM fungi were negatively correlated, indicating a trade‐off in responsiveness between a growth and defensive trait.ConclusionsOur results suggest that while there is substantial population differentiation in many traits of A. speciosa, populations respond similarly to AM fungi, and both positive and negative correlations among trait responses occur.
A Copper‐Catalyzed Domino Reaction of Alkynyl Bromides and Oxazolidine‐2‐thiones: Synthesis of Thiazol‐2‐ones
Authors: Xie Chunsong , Zhang Yuhong 
Published: March 2018

AbstractA copper‐catalyzed cyclization of alkynyl bromides and oxazolidine‐2‐thiones is described. C−N and C−S bonds are simultaneously constructed and a multi‐step process occurred to give the five‐member heterocycles of thiazol‐2‐ones containing 2‐alkylthio‐oxazolines. Optically active oxazolidine‐2‐thiones undergo the cyclization with complete retention of configuration.
Optogenetic Control of Voltage‐Gated Calcium Channels
Authors: Ma Guolin , Liu Jindou , Ke Yuepeng , Liu Xin , Li Minyong , Wang Fen , Han Gang , Huang Yun , Wang Youjun , Zhou Yubin 
Published: March 2018

AbstractVoltage‐gated Ca2+ (CaV) channels mediate Ca2+ entry into excitable cells to regulate a myriad of cellular events following membrane depolarization. We report the engineering of RGK GTPases, a class of genetically encoded CaV channel modulators, to enable photo‐tunable modulation of CaV channel activity in excitable mammalian cells. This optogenetic tool (designated optoRGK) tailored for CaV channels could find broad applications in interrogating a wide range of CaV‐mediated physiological processes.
In‐situ‐Untersuchungen mechanochemischer Eintopfreaktionen
Authors: Kulla Hannes , Haferkamp Sebastian , Akhmetova Irina , Röllig Mathias , Maierhofer Christiane , Rademann Klaus , Emmerling Franziska 
Published: March 2018

AbstractZur Untersuchung von Mahlreaktionen in Echtzeit wurden drei analytische Methoden gekoppelt: Synchrotron‐Röntgenbeugung mit Raman‐Spektroskopie und Thermographie. Diese Methodenkombination ermöglicht es, die strukturelle Entwicklung mit Temperaturinformationen zu korrelieren. Die Temperaturinformation ist entscheidend für das Verständnis von Thermodynamik und Reaktionskinetik. Exemplarisch wurde der Reaktionsmechanismus von drei mechanochemischen Modell‐Synthesen, einer Cokristallbildung, einer C‐C‐Bindungsknüpfung (Knoevenagel‐Kondensation) und der Bildung einer metallorganischen Verbindung, eines Mangan‐Phosphonats, aufgeklärt. Allgemeine Trends bezüglich der Temperaturentwicklung beim Mahlen konnten identifiziert werden. Die Reaktions‐ und Kristallisationswärme tragen zur gesamten Temperaturerhöhung bei. Eine Erniedrigung der Temperatur tritt bei Freisetzung von z. B. Wasser als Nebenprodukt auf. Die drei unabhängigen Methoden ergänzen sich gegenseitig, wodurch der Informationsgewinn maximiert und der Nachweis fester sowie flüssiger Intermediate ermöglicht wird. Schließlich konnte der Einfluss der mechanischen Einwirkung von den durch die Reaktion hervorgerufenen Temperatureinflüssen unterschieden werden.
Concerted Catalysis by Adjacent Palladium and Gold in Alloy Nanoparticles for the Versatile and Practical [2+2+2] Cycloaddition of Alkynes
Authors: Miura Hiroki , Tanaka Yumi , Nakahara Karin , Hachiya Yuka , Endo Keisuke , Shishido Tetsuya 
Published: March 2018

AbstractA Pd‐Au alloy efficiently catalyzed the [2+2+2] cycloaddition of substituted alkynes. Whereas monometallic Pd and Au catalysts were totally ineffective, Pd‐Au alloy nanoparticle catalysts with a low Pd/Au molar ratio showed high activity to give the corresponding polysubstituted arenes in high yields. A variety of substituted alkynes participated in various modes of cycloaddition under Pd‐Au alloy catalysis. The Pd‐Au alloy catalysts exhibited high air tolerance and reusability.
Die chemischen Grundlagen der Adhäsion von Catechol
Authors: Saiz‐Poseu J. , Mancebo‐Aracil J. , Nador F. , Busqué F. , Ruiz‐Molina D. 
Published: March 2018

AbstractDie Anhaftung einiger mariner Organismen in nasser Umgebung an fast jede Art von Oberfläche hat in den letzten Jahrzehnten zunehmendes Interesse geweckt. Zahlreiche Untersuchungen wurden durchgeführt, um die Grundlage für dieses Verhalten zu verstehen. Dabei wurde festgestellt, dass Catechol eine Schlüsselrolle spielt. Mithilfe des Wissens aus diesen Studien wurden einige neuartige bioinspirierte Klebstoffe und Beschichtungen mit zusätzlichem Nutzen entwickelt. Bisher gab es noch keine detaillierte Zusammenstellung, die sich ausschließlich auf die komplexe innere Funktionsweise dieser Materialien konzentrierte. Dieser Aufsatz befasst sich daher mit aktuellen Untersuchungen, die den Ursprung der Adsorptionskapazität von Catechol‐Derivaten und die Effekte von äußeren Faktoren aufklären, die wichtige Rollen im Gesamtprozess der Adhäsion spielen, z. B pH‐Wert, Lösungsmittel und Metallionen. Er beleuchtet die Details der Chemie, die für die erstaunlichen Eigenschaften Catechol‐haltiger adhäsiver Materialien verantwortlich sind.