bluuebunny/crossref_metadata_2025_split huggingface dataset:
Organic Photovoltaic Sensors for Photocapacitive Stimulation of Voltage‐Gated Ion Channels in Neuroblastoma Cells
Authors: Abdullaeva Oliya S. , Balzer Frank , Schulz Matthias , Parisi Jürgen , Lützen Arne , Dedek Karin , Schiek Manuela 
Published: October 2018

AbstractOrganic semiconductors are emerging as promising candidates for novel electrically self‐sufficient photovoltaic prosthetics for neurostimulation, especially for restoration of light sensitivity in degenerate retina. Considering future applications, it is essential to gain fundamental insight into the signaling mechanisms at the organic photosensor–electrolyte–neuron interface. Particularly, targeting voltage‐gated ion channels by a pure photocapacitive stimulation is a preferred therapeutic approach as it avoids redox reactions involved in Faradaic charge injection. The present study investigates whether single neuroblastoma (N2A) cells, grown on a photosensor based on a small molecular squaraine:fullerene photoactive layer blend, optionally covered with silicon dioxide, can be activated by photocapacitive stimulation. Indeed, upon pulsed illumination, a rapid transient photocurrent strongly depolarizes the membrane potential and subsequently activates fast‐responding voltage‐gated sodium channels. The dielectric top coating on the organic layer ensures sufficient capacitive charge injection efficiency while maintaining the rapid response of the device. Due to the high irradiance level required for photocapacitive stimulation, another slower, independent, and unintended, nonelectrical signaling pathway is identified. This activates voltage‐gated potassium channels, presumably by photothermal effects. The present study provides the basis for further improvements on standalone photovoltaic neurostimulating platforms based on organic photoactive layers.
Micro–Nano‐Texturing Inner Surfaces of Small‐Caliber High Aspect Ratio and Superhydrophobic Artificial Vessels using Femtosecond Laser Filamenting Pulses
Authors: Zhan Xue‐Peng , Wang Yi‐Jun , Su Yue , Li Mu‐Tian , Zang Hong‐Wei , Xia Hong , Xu Huai‐Liang , Liu Bin , Sun Hong‐Bo 
Published: October 2018

AbstractCardiovascular diseases, the leading cause of death worldwide in the last two decades, are mainly due to the pathological changes inside the heart or blood vessels. Current treatment prescription is to replace obstructed blood vessels by synthetic alternatives, but it can only cure patients effectually when the vessel diameter is larger than a certain value because the cell attachment capacity on a small‐caliber artificial vessel is usually unacceptable for long‐term patency. Here a femtosecond filamenting laser‐based fabrication approach that can produce in situ microstructures on the inner surface of small‐caliber tubules is reported. It is shown that the inner‐surface fabrication with an aspect ratio as high as 10:1 can be achieved and the processed samples exhibit significant changes in physical properties including topography, roughness, hydrophobicity, as well as in biological property with improved ability for Hela cells to adhere and grow. The results provide a possibility toward fabricating small‐caliber artificial vessels that might be suitable for long‐term patency use.
Synthesis of Molybdenum–Tungsten Bimetallic Carbide Hollow Spheres as pH‐Universal Electrocatalysts for Efficient Hydrogen Evolution Reaction
Authors: Lin Lifeng , Chen Min , Wu Limin 
Published: October 2018

AbstractDevelopment of highly efficient non‐noble metal electrocatalysts to replace platinum for hydrogen evolution reaction (HER) has attracted tremendous attention in recent years. In this work, a kind of novel MoxW2−xC@C hollow spheres with tunable stoichiometry is successfully synthesized. The synergetic effect of appropriate W‐introducing and hollow structure enables the composites to have superior performance for electrocatalytic HER and long‐term stability in a wide pH range. The MoxW2−xC@C with an optimized Mo/W ratio of 1.26/0.74 exhibits an overpotential (η10) of 106, 127, and 152 mV at 10 mA cm−2 in 1 m KOH, 0.5 m H2SO4, and 1 m phosphate buffer saline (PBS), respectively, and its overpotential in high current density region (η300) is only 237 and 250 mV in alkaline and acidic electrolytes, which are significantly better than most of the previously reported electrocatalysts.
Activated‐Carbon‐Supported Calcium Oxide: A Selective and Efficient Catalyst for Nitrile‐Containing Diaryl Ether Synthesis
Authors: Han Yue , Wang Guangxing , Qiu Wenfeng , Guo Ying , Sun Yanan , Zhang Youlan , Zhou Heng , Zhao Tong 
Published: October 2018

AbstractActivated‐carbon‐supported calcium oxide (CaO@AC) was prepared from AC and a suspension derived from CaO and ammonium carbonate. After calcination under nitrogen, high purity CaO@AC was obtained. The nature of non‐aggregation and high purity of CaO@AC enabled a clean and selective synthesis protocol for nitrile‐containing diaryl ethers. Various functional groups including methoxyl, amino, carboxyl, allyl and nitro were well‐tolerated, and products were obtained in excellent yields and purities. Asymmetric substitutions could be achieved via simple adjustment of reaction conditions, and transetherification was greatly suppressed to 10−3–10−4 scale. In addition, a mechanism for suppression in transetherification was proposed and discussed.
Selbstanordnung von BODIPY‐Farbstoffen als Werkzeug, um die Antitumoraktivität von Capsaicin bei Prostatakrebs zu erhöhen
Authors: Sampedro Angel , Ramos‐Torres Ágata , Schwöppe Christian , Mück‐Lichtenfeld Christian , Helmers Ingo , Bort Alicia , Díaz‐Laviada Inés , Fernández Gustavo 
Published: October 2018

AbstractCapsaicin (CAP) ist seit Längerem für dessen analgetische Wirkung sowie seit Kurzem für seine Antitumoraktivität an verschiedenen Zelltypen bekannt. Aufgrund seiner Schärfe und der benötigten hohen Dosen zur Erzielung einer signifikanten Aktivität hat dieser Wirkstoff bis heute keine Anwendung in der Krebstherapie gefunden. In dieser Arbeit zeigen wir eine neuartige Strategie, um die Aktivität dieses Wirkstoffes zu verbessern. Durch den Austausch der hydrophoben Terpeneinheit durch einen BODIPY‐Farbstoff wurde die Neigung zur Aggregation erhöht. Die Verbindung CAP‐BDP 1 lagert sich in wässrigen Medien zu schwach fluoreszierenden sphärischen Anordnungen zusammen, die durch die Aufnahme in die Zelle zur hoch fluoreszierenden Monomereinheiten disassemblieren. Bemerkenswert ist, dass der Transport in das Tumorgewebe mithilfe dieser Aggregate verbessert werden und somit die wirksame Dosis in vivo bei Prostatakrebszellen um zwei Größenordnungen reduziert werden konnte.
Quadruply Twisted Hückel‐Aromatic Dodecaphyrin
Authors: Soya Takanori , Mori Hirotaka , Osuka Atsuhiro 
Published: October 2018

AbstractMolecular topology of π‐conjugated circuits becomes increasingly important in the chemistry of aromatic and antiaromatic compounds. meso‐Pentafluorophenyl‐substituted 5,35‐(1,4‐phenylene)bridged [56]dodecaphyrin was synthesized by condensation of 1,4‐phenylene‐bridged dicarbinol dimer and 5,10,15‐tris‐(pentafluorophenyl)tetrapyrrane followed by oxidation with DDQ and was oxidized to its [54]‐ and [52]congeners in a stepwise manner. Metalation of the [52]dodecaphyrin with Pd2(dba)3 gave two bis‐PdII complexes that are isomers of metalation sites: anti and syn with regard to the 1,4‐phenylene bridge. The anti‐isomer was easily oxidized to its N‐fused form, a quadruply twisted non‐aromatic or weakly aromatic macrocycle. On the other hand, the syn‐isomer was revealed to be the first example of Hückel aromatic molecule with a quadruply twisted structure.
Palladium‐Catalyzed C−H Alkenylation of Arenes with Alkynes: Stereoselective Synthesis of Vinyl Chlorides via a 1,4‐Chlorine Migration
Authors: Li Zhen , Duan Wei‐Liang 
Published: October 2018

AbstractA directing group‐free, ligand‐promoted palladium‐catalyzed C−H arylation of internal alkynes with simple arenes was developed. Alkenyl chlorides resulting from a 1,4‐chlorine migration or trisubstituted alkenes were produced in moderate to good yields depending on the type of alkyne.
Facile Synthesis of Sequence‐Regulated Synthetic Polymers Using Orthogonal SuFEx and CuAAC Click Reactions
Authors: Yang Cangjie , Flynn James P. , Niu Jia 
Published: October 2018

AbstractThe orthogonal sulfur–fluoride exchange reaction (SuFEx) and copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) are employed to synthesize sequence‐regulated synthetic polymers. The high efficiency and broad tolerance of SuFEx and CuAAC to diverse chemical functionalities enable the one‐pot synthesis of polydispersed sequence‐controlled polymers by step‐growth copolymerization in high yield and sequence complexity. Furthermore, iterative SuFEx and CuAAC coupling reactions on a solid support, without the need of protecting groups, afford monodispersed sequence‐defined oligomers. The use of this orthogonal pair of click reactions provides new opportunities to facilely access sequence‐regulated synthetic polymers with a high degree of structural diversity.
Platinum‐Catalyzed Desaturation of Lactams, Ketones, and Lactones
Authors: Chen Ming , Rago Alexander J. , Dong Guangbin 
Published: October 2018

AbstractThe development of a general platinum‐catalyzed desaturation of N‐protected lactams, ketones, and lactones to their conjugated α,β‐unsaturated counterparts is reported. The reaction operates under mildly acidic conditions at room temperature or 50 °C. It is scalable and tolerates a wide range of functional groups. The complementary reactivity to the palladium‐catalyzed desaturation is demonstrated in the efficient conversion of iodide, bromide, and sulfur‐containing substrates.
Rapid Structure Determination of Microcrystalline Molecular Compounds Using Electron Diffraction
Authors: Gruene Tim , Wennmacher Julian T. C. , Zaubitzer Christan , Holstein Julian J. , Heidler Jonas , Fecteau‐Lefebvre Ariane , De Carlo Sacha , Müller Elisabeth , Goldie Kenneth N. , Regeni Irene , Li Teng , Santiso‐Quinones Gustavo , Steinfeld Gunther , Handschin Stephan , van Genderen Eric , van Bokhoven Jeroen A. , Clever Guido H. , Pantelic Radosav 
Published: October 2018

AbstractChemists of all fields currently publish about 50 000 crystal structures per year, the vast majority of which are X‐ray structures. We determined two molecular structures by employing electron rather than X‐ray diffraction. For this purpose, an EIGER hybrid pixel detector was fitted to a transmission electron microscope, yielding an electron diffractometer. The structure of a new methylene blue derivative was determined at 0.9 Å resolution from a crystal smaller than 1×2 μm2. Several thousand active pharmaceutical ingredients (APIs) are only available as submicrocrystalline powders. To illustrate the potential of electron crystallography for the pharmaceutical industry, we also determined the structure of an API from its pill. We demonstrate that electron crystallography complements X‐ray crystallography and is the technique of choice for all unsolved cases in which submicrometer‐sized crystals were the limiting factor.
Bioproducts from wheat gluten with high strength and aqueous stability using cashew nut shell liquid as plasticizer
Authors: Guna Vijaykumar , Ilangovan Manikandan , Nataraj Divya , Reddy Narendra 
Published: October 2018

ABSTRACTCashew nut shell liquid (CNSL) provides wheat gluten films with mechanical properties similar to but considerably higher resistance to water than glycerol‐plasticized films. Obtaining biopolymeric films with good water stability without using synthetic polymers or extensive chemical modifications is a challenge. Wheat gluten is a preferred protein for manufacturing films for food and nonfood applications, but obtaining water‐stable gluten films is difficult. Glycerol and other plasticizers have been extensively used to develop films, but these plasticizers inevitably decrease strength and resistance to water. CNSL is a byproduct obtained during processing of cashew nuts and is available in large quantities at low cost. In this research, we studied the possibility of substituting CNSL for glycerol as the plasticizer for wheat gluten films. Wheat gluten was compression molded into films with 10%, 20%, or 30% CNSL or glycerol, and the changes in mechanical properties, stability in water, thermal behavior, and surface wettability were determined. It was observed that CNSL provided similar strength, 80 to 100 times higher modulus, and considerably higher resistance to water but lower elongation compared to glycerol‐treated films. It was possible to obtain films with the desired mechanical properties and water stability by controlling the amount of CNSL and processing conditions. Wheat gluten can be converted into completely biodegradable cups, containers, coffee pods, and other bioproducts using this approach. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46719.
Photodegradation of copolyester films: A mechanistic study
Authors: Arangdad Kiarash , Detwiler Andrew , Cleven Curtis D. , Burk Christopher , Shamey Renzo , Pasquinelli Melissa A. , Freeman Harold , El‐Shafei Ahmed 
Published: October 2018

ABSTRACTThe photodegradation of copolyesters based on 1,4‐cyclohexanedimethanol (CHDM), tetramethyl‐1,3‐cyclobutanediol, and terephthalic acid units was investigated using various analytical methods. Photodegradation products were characterized using Fourier transform infrared (FTIR), liquid chromatography–mass spectrometry (LC–MS), and X‐ray Photoelectron spectroscopy (XPS) analysis. The homolytic scission of C‐O bonds of ester groups through a Norrish Type I reaction was supported by time of flight secondary ion mass spectrometry and LC–MS results, while nuclear magnetic resonance analysis confirmed hydrogen abstraction from the tertiary carbon of CHDM units in the trans (equatorial‐equatorial) conformation. Chain scission through Norrish Type II reaction is also responsible for the formation of carboxylic acid end group. Fluorescence emission from irradiated glycol modified poly(ethylene terephthalate) films demonstrated the formation of mono‐ and dihydroxyterephthalate species. Furthermore, FTIR and XPS valence band analysis confirmed configurational changes, in the polymer chain due to photodegradation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47148.
Characterization of different forms of vulcanized natural rubbers as elastomer spacer and toughening agent in two‐matrix filled epoxy/natural rubber/graphene nano‐platelets system
Authors: Kam Ka Wei , Teh Pei Leng , Osman Hakimah , Yeoh Cheow Keat 
Published: October 2018

ABSTRACTThis paper compares the effects of different forms of vulcanized natural rubbers on the physical, mechanical, thermal, and electrical performances of filled epoxy systems. In this study, natural rubber (NR), liquid natural rubber (LNR), and recycled natural rubber (rNR) were introduced into filled epoxy systems. The results show that flexural strength, modulus, and toughness properties of filled epoxy system were enhanced with NR phases, as compared to those with LNR and rNR. Scanning electron micrograph revealed that the particle sizes of NR phases dispersed within epoxy matrix were smaller and more uniform, as compared to those with LNR and rNR phases. Incorporation of NR phases has improved the thermal stability of filled system, followed by LNR and rNR. This is attributed to more heat energy needed to overcome good interfacial bonding between epoxy matrix and small NR phases. X‐ray diffraction analysis result showed that filled epoxy/NR/GNP system has higher 2θ values, indicated that d‐spacing in between GNP nano‐fillers has the closer distance. Electrical bulk conductivity values of filled epoxy/NR/GNP system were the highest. Small NR phases acted as elastomer spacers, which provided better “GNP packing efficiency” and realigned the GNP nano‐fillers to form more effective conductive pathways for electrons hopping. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47188.
Discrete Fractional‐Order BAM Neural Networks with Leakage Delay: Existence and Stability Results
Authors: Alzabut Jehad , Tyagi Swati , Abbas Syed 
Published: October 2018

AbstractIn this paper, a discrete model of fractional‐order bidirectional associative memory (BAM) neural networks with leakage delay is considered. Sufficient conditions are established for the existence, uniqueness and uniform stability of nontrivial solutions of the addressed model. Our approach is based on the implementation of the newly defined discrete fractional calculus, mathematical inequalities and fixed point theorems. We provide an example that supports the application of the theoretical results.
Zeolitic Imidazolate Framework‐Derived Core‐Shell‐Structured CoS2/CoS2‐N‐C Supported on Electrochemically Exfoliated Graphene Foil for Efficient Oxygen Evolution
Authors: Cao Junhui , Lei Chaojun , Yang Bin , Li Zhongjian , Lei Lecheng , Hou Yang , Feng Xinliang 
Published: October 2018

AbstractDeveloping earth‐abundant transition‐metal based materials to efficiently catalyze the oxygen evolution reaction (OER) is an urgent demand for electrochemical water splitting and rechargeable metal‐air batteries. Here, we developed a novel 3D hybrid electrocatalyst consisting of core‐shell structured CoS2/CoS2 embedded into N‐doped carbon supported on electrochemically exfoliated graphene foil (EG/CoS2/CoS2‐NC) by sulfurization treatment of EG/Co(OH)2/zeolitic imidazolate framework‐67 (ZIF‐67) as precursor. The thickness of the CoS2‐NC shell derived from ZIF‐67 is 10 nm and the CoS2 core generated from Co(OH)2 nanosheet arrays has a particle size of ∼20 nm. Benefiting from the unique 3D core‐shell structure and synergistic effects, the EG/CoS2/CoS2‐NC hybrid enormously promotes electrocatalytic OER activity with a low overpotential of 210 mV at a current density of 10 mA cm−2 and a small Tafel slope of 61.9 mV dec−1. These values are far superior compared to the commercial Ir/C catalyst, and even better than other reported state‐of‐the‐art CoS2‐based materials. In‐situ Raman spectroscopy together with ex‐situ XRD patterns reveal that the active centers of EG/CoS2/CoS2‐NC hybrid are proven to be Co‐OOH species that are derived from Co−S groups during the OER process. The superb catalytic performance is also reflected in boosting electrochemical urea oxidation and hydrazine oxidation, where the accelerated oxidation reaction could be observed.
Consumer familiarity, ambiguity tolerance, and purchase behavior toward remanufactured products: The implications for remanufacturers
Authors: Wang Shanyong , Wang Jing , Yang Feng , Wang Yu , Li Jun 
Published: October 2018

AbstractRemanufacturing plays an important role in reducing energy consumption and material usage. The present research attempted to understand consumers' perceptions of remanufactured products in China and their resulting purchase behavior. The study uses the theory of planned behavior as its theoretical framework but extends it by incorporating two additional variables (consumer familiarity and ambiguity tolerance). Data was collected using a self‐administered questionnaire survey and analyzed with structural equation modeling. According to the survey findings, consumer familiarity positively affects consumer attitude but negatively affects consumer intention to purchase remanufactured products. Ambiguity tolerance positively affects attitude and purchase intention. Meanwhile, consumer attitude and perceived behavioral control are both positively and significantly related to purchase intention. However, the subjective norm has no significant effect on purchase intention. This study also demonstrated the positive effect of purchase intention on actual purchase behavior. Based on the research findings, practical guidelines are given for remanufacturers to motivate consumers to purchase remanufactured products.
The impact of market structure on environmental efficiency in the United States: A quantile approach
Authors: Halkos George E. , Polemis Michael L. 
Published: October 2018

AbstractThis paper investigates the relationship between efficiency and market structure for a sample of industrial facilities dispersed among the U.S. states. In order to measure the relevant efficiency scores, we use a data envelopment analysis allowing for the inclusion of desirable and undesirable (toxic chemical releases) outputs in the production function. In the next stage, we utilize the bootstrapped quantile regression methodology to uncover possible nonlinear relationships between efficiency and competition at the mean and at various quantiles before and after the global financial crisis (2002 and 2012). In this way, we impose no functional form constraints on parameter values over the conditional distribution of the dependent variable (efficiency). At the same time, we estimate at which part of its cumulative distribution function the efficiency is located and draw substantial conclusions about the range of policy measures obtained. The empirical findings indicate that the relationship between efficiency and market concentration did change in the aftermath of the global financial crisis. The empirical results survived robustness checks under the inclusion of an alternative market concentration indicator (CR8).
Systematic Modulation of the Supramolecular Gelation Properties of Bile Acid Alkyl Amides
Authors: Kuosmanen Riikka , Puttreddy Rakesh , Rissanen Kari , Sievänen Elina 
Published: October 2018

AbstractThe self‐assembly properties of nine low‐molecular‐weight gelators (LMWGs) based on bile acid alkyl amides were studied in detail. Based on the results, the number of hydroxyl groups attached to the steroidal backbone plays a major role in the gelation, although the nature of the aliphatic side chain also modulates the gelation abilities. Of the 50 gel systems studied, 35 are based on lithocholic acid and 15 on cholic acid derivatives. The deoxycholic acid derivatives did not form any gels. The gelation occurred primarily in aromatic solvents and the gels manifested typical fibrous or spherical morphologies. The 13C cross‐polarized magic angle spinning (CPMAS) NMR spectra measured on the crystalline materials and the corresponding wet organogels were analogous, suggesting that the chemical environments, that is, the intermolecular interactions found in the two materials were similar. The single‐crystal X‐ray structures of all nine bile‐acid amide derivatives studied revealed very similar molecular conformations in the solid state and gave insights into the possible intermolecular interactions in the gel state.
Facile Preparation of Nanofibrillar Networks of “Ureido‐Chitin” Containing Ureido and Amine as Chelating Functional Groups
Authors: Ganesan Kathirvel , Heyer Markus , Ratke Lorenz , Milow Barbara 
Published: October 2018

AbstractAerogels of polysaccharides with chelating functions can be useful as supports in many applications because of their hosting properties. This work demonstrates a facile method for the preparation of aerogels of chitosan derivative “ureido‐chitin”, containing ureido functional groups. The nanofibrillar networks of “ureido‐chitin” were produced by the nucleophilic addition of amine groups of chitosan with isocyanic acid prepared in situ. The presence of ureido functional groups was confirmed by FTIR, solid‐state CP‐MAS 13C and 15N NMR analyses. No crosslinking of molecular chains was observed. The maximum degree of ureido functional groups was estimated to be about 66 %. Characterization by powder XRD confirmed that the polymer chains self‐assembled, with the chitin polymers oriented in a highly ordered crystalline structure. The nanofibrillar networks showed no solubility under either aqueous acidic or alkaline conditions. Bio‐based hosting materials of this kind with two different hosting functional groups, ureido and amine, can potentially be utilized for a wide range of applications in aqueous medium, including filters, catalysis and biomedicine.