bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facilitated Water Transport through Graphene Oxide Membranes Functionalized with Aquaporin‐Mimicking Peptides
Authors: Lee Chang Seon , Choi Moon‐ki , Hwang Ye Young , Kim Hyunki , Kim Moon Ki , Lee Yun Jung 
Published: February 2018

AbstractWater purification by membranes is widely investigated to address concerns related to the scarcity of clean water. Achieving high flux and rejection simultaneously is a difficult challenge using such membranes because these properties are mutually exclusive in common artificial membranes. Nature has developed a method for this task involving water‐channel membrane proteins known as aquaporins. Here, the design and fabrication of graphene oxide (GO)‐based membranes with a surface‐tethered peptide motif designed to mimic the water‐selective filter of natural aquaporins is reported. The short RF8 (RFRFRFRF, where R and F represent arginine and phenylalanine, respectively) octapeptide is a concentrated form of the core component of the Ar/R (aromatic/arginine) water‐selective filter in aquaporin. The resulting GO‐RF8 shows superior flux and high rejection similar to natural aquaporins. Molecular dynamics simulation reveal the unique configuration of RF8 peptides and the transport of water in GO‐RF8 membranes, supporting that RF8 effectively emulates the core function of aquaporins.
Soft Somatosensitive Actuators via Embedded 3D Printing
Authors: Truby Ryan L. , Wehner Michael , Grosskopf Abigail K. , Vogt Daniel M. , Uzel Sebastien G. M. , Wood Robert J. , Lewis Jennifer A. 
Published: February 2018

AbstractHumans possess manual dexterity, motor skills, and other physical abilities that rely on feedback provided by the somatosensory system. Herein, a method is reported for creating soft somatosensitive actuators (SSAs) via embedded 3D printing, which are innervated with multiple conductive features that simultaneously enable haptic, proprioceptive, and thermoceptive sensing. This novel manufacturing approach enables the seamless integration of multiple ionically conductive and fluidic features within elastomeric matrices to produce SSAs with the desired bioinspired sensing and actuation capabilities. Each printed sensor is composed of an ionically conductive gel that exhibits both long‐term stability and hysteresis‐free performance. As an exemplar, multiple SSAs are combined into a soft robotic gripper that provides proprioceptive and haptic feedback via embedded curvature, inflation, and contact sensors, including deep and fine touch contact sensors. The multimaterial manufacturing platform enables complex sensing motifs to be easily integrated into soft actuating systems, which is a necessary step toward closed‐loop feedback control of soft robots, machines, and haptic devices.
Synthesis, Application and Kinetic Studies of Chiral Phosphite‐Oxazoline Palladium Complexes as Active and Selective Catalysts in Intermolecular Heck Reactions
Authors: Mazloomi Zahra , Magre Marc , Del Valle Efrem , Pericàs Miquel A. , Pàmies Oscar , van Leeuwen Piet W. N. M. , Diéguez Montserrat 
Published: February 2018

AbstractThis study identifies new phosphite‐oxazoline ligands that have been successfully applied in the palladium‐catalyzed intermolecular asymmetric Heck reaction. The design of the new phosphite‐oxazoline ligands derives from a previous successful generation of phosphine‐oxazoline ligands, by replacing the phosphine group with several π‐acceptor biaryl phosphite moieties. With these simple modifications, the new phosphite‐based ligands, unlike previous phosphine‐oxazoline, not only present a modular design with numerous potential phosphite groups available, but they are also air‐stable solids, which can be made in the same number of synthetic steps as the phosphine analogues. The substitution of the phosphine by a biaryl phosphite group extended the range of substrates and triflates sources that can be coupled with regio‐, enantioselectivities and activities comparable to the few best ones reported. In addition, the ligands that provided the best selectivities contained an isopropyl oxazoline moiety instead of the tert‐butyl group found in the related phosphine‐oxazoline ligands, which is made from a much more expensive precursor. In this paper we have also carried out kinetic studies and a Hammett plot analysis to determine the rate determining step of this system in the regime of interest. We suggest a likely explanation for the fast Heck reaction of the phosphite‐oxazoline catalysts.magnified image
Selective Synthesis of Primary Amines from Nitriles under Hydrogenation Conditions
Authors: Yoshimura Masatoshi , Komatsu Akira , Niimura Masaru , Takagi Yukio , Takahashi Tohru , Ueda Shun , Ichikawa Tomohiro , Kobayashi Yutaka , Okami Hiroki , Hattori Tomohiro , Sawama Yoshinari , Monguchi Yasunari , Sajiki Hironao 
Published: February 2018

AbstractThe hydrogenation of aliphatic nitriles over Pd/C, Pd/Al2O3, and Pd−Au/Al2O3 catalysts were evaluated for the selective hydrogenation of aliphatic nitriles to the corresponding primary amines. The highest selectivity (>99%) toward primary amines was achieved when the reaction was carried out in acetic acid using 10 mol% of 25% Pd‐5% Au/Al2O3 under relatively low hydrogen pressure (0.8 MPa). Characterization of the catalysts by XRD, CO adsorption experiments, and EXAFS revealed that the excellent selectivity of 25% Pd‐5% Au/Al2O3 toward the synthesis of primary amines is determined by the electronic properties and/or the surface structure resulting from alloying Pd with Au.magnified image
Der präexponentielle Faktor in der Elektrochemie
Authors: He Zheng‐Da , Chen Yan‐Xia , Santos Elizabeth , Schmickler Wolfgang 
Published: February 2018

AbstractWie in vielen Zweigen der Wissenschaft, um nicht von der Kultur im Allgemeinen zu reden, so gibt es auch in der Elektrochemie eine Reihe von wiederkehrenden Themen: Forschungsgebiete, die eine Zeit lang populär sind, dann verblassen, wenn ihre Möglichkeiten erschöpft scheinen, um Jahrzehnte später wieder aktuell zu werden, wenn Fortschritte in experimentellen oder theoretischen Techniken neue Forschungsmöglichkeiten eröffnen. Ein gutes Beispiel sind Brennstoffzellen, die fünf solcher Zyklen durchlaufen haben; aber hier soll ein allgemeineres Konzept der Kinetik diskutiert werden, nämlich der präexponentielle Faktor einer Geschwindigkeitskonstanten, der bisher zwei solcher Zyklen durchlaufen hat. Der erste Zyklus umfasst etwa die Zeitspanne 1950 bis 1980, als die Methoden der elektrochemischen Kinetik entwickelt wurden und die Interpretationen auf der Theorie des Übergangszustands basierten. Der zweite wurde durch die Wiederentdeckung der Kramers‐Theorie für Reaktionen in kondensierten Phasen ausgelöst. Dieser Kurzaufsatz soll zeigen, dass es Zeit für einen dritten Zyklus ist, der auf neuen Ergebnissen in der Elektrokatalyse beruht.
Elektronentransfer um eine molekulare Ecke
Authors: Schmidt Hauke C. , Larsen Christopher B. , Wenger Oliver S. 
Published: February 2018

AbstractDie Distanzabhängigkeit des intramolekularen Elektronentransfers (ET) wird typischerweise in linearen Modellverbindungen mit starrer Geometrie untersucht, wobei Studien über molekulare Kabel, die einen 90°‐Winkel aufweisen, nur sehr selten sind. Über Variation des Substitutionsmusters an einer Spirobifluoreneinheit als zentralen Brückenbaustein konnten zwei isomere Serien von Donor‐Brücke‐Akzeptor‐Verbindungen mit näherungsweise linearer bzw. gewinkelter Geometrie erhalten werden. Der lichtinduzierte ET erfolgt über einen raschen Lochtransfer über die Oligofluorenbrücke über Distanzen von bis zu 70 Å in beiden Serien. Ungeachtet der konformationellen Flexibilität ist ein direkter ET (durch den Raum oder das Lösungsmittel) selbst in der gewinkelten Serie vernachlässigbar. Die Geschwindigkeitskonstante des ET in der gewinkelten Serie ist unabhängig von der Anzahl der Fluorenbrückeneiheiten, was einem geschwindigkeitsbestimmenden Tunnelschritt durch die Spirobifluorenecke zugeschrieben werden kann. Dieser Befund besitzt große Relevanz für multidimensionale ET‐Systeme sowie (supramolekulare) Gitternetze, in denen die Verbindungen der einzelnen molekularen Kabel einen 90°‐Winkel aufweisen.
Synthesis and Applications of Compartmentalised Molecular Polymer Brushes
Authors: Pelras Théophile , Mahon Clare S. , Müllner Markus 
Published: February 2018

AbstractPolymer science is rapidly advancing towards the precise construction of synthetic macromolecules of formidable complexity. Beyond the impressive advances in control over polymer composition and uniformity enabled by the living polymerisation revolution, the introduction of compartmentalisation within polymer architectures can elevate their functionality beyond that of their constituent parts, thus offering immense potential for the production of tailor‐made nanomaterials. In this Minireview, we discuss synthetic routes to complex molecular brushes with discrete chemical compartments and highlight their potential in the development of advanced materials with applications in nanofabrication, optics and functional materials.
Morphology enhancement of TiO2/PVP composite nanofibers based on solution viscosity and processing parameters of electrospinning method
Authors: Mirmohammad Sadeghi Soraya , Vaezi Mohammadreza , Kazemzadeh Asghar , Jamjah Roghayeh 
Published: February 2018

ABSTRACTIn this work, different sol solutions with various titanium tetraisopropoxide (TIP)/glacial acetic acid ratios in 2‐propanol with 5 wt % poly(vinyl pyrrolidone) (PVP) (Mw = 360,000 g/mol) were prepared and electrospun. Composition of the prepared sols and as‐spun TiO2/PVP nanofibers were determined by Fourier transform infrared and Raman spectroscopy methods. Morphology of the electrospun TiO2/PVP nanofibers was studied by scanning electron microscopy and transmission electron microscopy (TEM) techniques. Rheometry measurements of the sol solutions showed decrease of viscosity upon the addition of TIP to the polymer solutions with constant polymer and acid concentrations. The sol solution having the lowest viscosity (at shear rate 10 s−1) but the highest TIP/glacial acetic acid ratio showed beaded nanofibers morphology when electrospun under 10 and 12 kV applied voltage while injection rate, needle tip to collector distance, and needle gauge were kept constant. However, smooth electrospun TiO2/PVP composite nanofibers with the average nanofibers diameters (148 ± 79 nm) were achieved under the same condition when applied voltage increased to 15 kV. TEM micrographs of the electrospun TiO2/PVP nanofiber showed that the TiO2 particles with continuous structure are formed at the middle of the nanofiber and distributed along its axis. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46337.
Microwave‐Assisted Preparation and Characterization of a Polyoxometalate‐Based Inorganic 2D Framework Anode for Enhancing Lithium‐Ion Battery Performance
Authors: Nie Yan‐Mei , Liang Shuang , Yu Wei‐Dong , Yuan Hao , Yan Jun 
Published: February 2018

AbstractA pure inorganic 2D network molybdophosphate, [Mn3Mo12O24(OH)6(HPO3)8(H2O)6]4− (1 a), synthesized through microwave irradiation with the existence of Mn2+ and organic cations and isolated as [(CH3)2NH2]3Na[Mn3Mo12O24(OH)6(HPO3)8(H2O)6]⋅12 H2O (1), is found to possess highly enhanced performance in lithium‐ion batteries’ anode materials. The molecule shows multielectron redox properties suitable for producing anode materials with a specific capacity of 602 mA h g−1 at 100 mA g−1 after 50 cycles in lithium‐ion batteries, although its specific capacity is the highest among all the reported pure inorganic 2D polyoxometalates to date, the cyclic stability is not that satisfactory. A hybrid nanocomposite of this 2D network and polypyrrole cations effectively reduces the capacity fading in initial cycles, and increases the stability and improves the electrochemical performance of lithium‐ion batteries as well.
Need (more than) two to Tango: Multiple tools to adapt to changes in oxygen availability
Authors: Fratantonio Deborah , Cimino Francesco , Speciale Antonio , Virgili Fabio 
Published: February 2018

AbstractOxygen is a fundamental element for the life of a large number of living organisms allowing an efficient energetic utilization of substrates. Organisms relying on oxygen evolved complex structures for oxygen delivery and biochemical machineries dealing with its safe utilization and the ability to overcome the potentially harmful consequences of changes in oxygen availability. On fact, cells composing complex Eukaryotic organisms are set to live within an optimum narrow range of oxygen, quite specific for each cell type. Minute modifications of oxygen availability, either positive or negative, induce the expression of specific genes, the major actors of this responses being the transcription factors HIF and Nrf2 that control the attempt to cope with low oxygen (hypoxia) or to either high oxygen or to an oxygen “overflow,” respectively. This review describes the interaction between these two transcription factors and their interaction with the transcription factor NF‐κB acting as a pivotal determinant of final cell response. © 2018 BioFactors, 44(3):207–218, 2018
Mannose‐Decorated Multicomponent Supramolecular Polymers Trigger Effective Uptake into Antigen‐Presenting Cells
Authors: Straßburger David , Stergiou Natascha , Urschbach Moritz , Yurugi Hajime , Spitzer Daniel , Schollmeyer Dieter , Schmitt Edgar , Besenius Pol 
Published: February 2018

AbstractA modular route to prepare functional self‐assembling dendritic peptide amphiphiles decorated with mannosides, to effectively target antigen‐presenting cells, such as macrophages, is reported. The monomeric building blocks were equipped with tetra(ethylene glycol)s (TEGs) or labeled with a Cy3 fluorescent probe. Experiments on the uptake of the multifunctional supramolecular particles into murine macrophages (Mφs) were monitored by confocal microscopy and fluorescence‐activated cell sorting. Mannose‐decorated supramolecular polymers trigger a significantly higher cellular uptake and distribution, relative to TEG carrying bare polymers. No cytotoxicity or negative impact on cytokine production of the treated Mφs was observed, which emphasized their biocompatibility. The modular nature of the multicomponent supramolecular polymer coassembly protocol is a promising platform to develop fully synthetic multifunctional vaccines, for example, in cancer immunotherapy.
Pneumothorax secondary to pulmonary alveolar microlithiasis
Authors: Devine Oliver P. , Harborne Andrew C. 
Published: February 2018

Key Clinical MessagePulmonary alveolar microlithiasis (PAM) is a rare impairment of pulmonary phosphate clearance that leads to gradual precipitation of intra‐alveolar calcium phosphate microliths. There is often a striking difference between alarming clinical imaging and a relatively well patient. Pneumothorax in PAM often only respond to surgical intervention.
Feasibility of peak volume algorithm in electrothermal vaporization microwave plasma atomic emission spectrometry
Authors: Shan Jin , Jin Wei , Yu Bingwen , Ying Yangwei , Zhu Dan , Yu Haixiang , Yan Yuwei , Jin Qinhan 
Published: February 2018

AbstractElectro‐thermal vaporization has served as an alternative sample introduction method in atomic spectrometry for some time and provided a better solution for quick analysis of complicated samples because of its high sensitivity and effective separation of analyte from matrix materials. The quick heating process produces sharp signals that can provide much better limits of detection with significant improvements compared with the nebulization sample introduction method. However, it also makes the results worse repeatable, which leads to a worse analytical precision. To improve the precision of the newly developed electrothermal vaporization microwave plasma atomic emission spectrometry and to make good use of the limited data obtained in a limited period of time, some different evaluation methods, such as peak height (symbol, Ih), peak area (symbol, IΣt), and peak volume (symbol, IΣλ‐t) for the results treatment are compared in this paper. It comes out that the results calculated by the optimized peak volume algorithm can significantly improve the precision and retain the high linearity at the same time. Limit of detection of this electrothermal vaporization microwave plasma atomic emission spectrometry system used in this paper for Cu was shown to be 1 μg/L, and the relative standard deviation of 11 repeated measurements can be improved from 10% to 5.6% while retaining good linearity, as expressed by both the squared correlation coefficient obtained with optimized peak volume algorithm and with raw peak height method (squared correlation coefficient of the standard curve R2 > 0.999).
Multifunctional Ionic Liquids from Rhodium(I) Isocyanide Complexes: Thermochromic, Fluorescence, and Chemochromic Properties Based on Rh−Rh Interaction and Oxidative Addition
Authors: Tominaga Takumi , Mochida Tomoyuki 
Published: February 2018

AbstractSquare‐planar rhodium(I) isocyanide complexes exhibit unique chemical reactivities such as the formation of Rh−Rh bonds and oxidative addition. This paper details the syntheses and properties of multifunctional ionic liquids containing RhI isocyanide complexes [Rh(nBuNC)4]X (X=Tf2N (=N(SO2CF3)2−), Nf2N (=N(SO2C4F9)2−), FSA (=N(SO2F)2−), CF3BF3−). Salts with Tf2N and Nf2N were liquids, whereas those with FSA and CF3BF3 were solids at room temperature. The salts exhibited thermochromism in the liquid state, changing from orange at high temperatures to blue‐purple at lower temperatures. This is based on the equilibrium between monomer, dimer, and other oligomers associated with Rh−Rh bond formation. The salts also exhibited fluorescence. Exposure of the Tf2N salt to methyl iodide vapor produced ionic liquid mixtures [Rh(nBuNC)4]x[Rh(nBuNC)4IMe](1−x)[Tf2N], concomitant with a color change from purple to red, orange, and yellow, extending the thermochromic color range. The reaction of the Tf2N salt and iodine produced mononuclear and polynuclear iodine adducts. Thus, these liquids exhibit thermochromism, fluorescence, vapochromism, chemical reactivities, and characteristic properties of ionic liquids.
Methanol Synthesis by CO2 Hydrogenation over Cu/ZnO/Al2O3 Catalysts under Fluctuating Conditions
Authors: Zurbel Alexander , Kraft Michael , Kavurucu‐Schubert Sena , Bertau Martin 
Published: February 2018

AbstractMethanol synthesis through CO2 hydrogenation under fluctuating conditions was investigated over a CuO/ZnO/Al2O3 catalyst in an integral reactor. The performance of the catalyst was examined under stable conditions at 563 K and 80 bar. For dynamic experiments, the H2/CO2 ratio of the feed gas was changed sequentially. Although the activity and selectivity towards methanol of the catalyst was affected more under dynamic conditions, long‐term stability of the synthesis process was not influenced. The results show that it is possible to operate methanol synthesis with a fluctuating feed gas composition, as it is the case when CO2 is captured from a power plant and H2 from an electrolysis unit driven by a regenerative energy source, such as solar or wind power.
Chemical Conversion of Carbon Dioxide
Authors: Behr Arno , Kuhlmann René 
Published: February 2018

AbstractEine Minimierung von Kohlendioxid‐Emissionen wird seit einigen Jahren von Gesellschaft und Politik gefordert. Die hohen verfügbaren Mengen an leicht gewinnbarem CO2 machen auch eine chemische Verwendung des Abfallstoffes zunehmend interessant. Während bereits einige wenige industrielle Prozesse Kohlendioxid großtechnisch verwenden, sind weitere Forschungs‐ und Pilotprojekte mit dem Ziel einer wirtschaftlichen CO2‐Nutzung bereits in Planung. Einige vielversprechende Ansätze zur chemischen CO2‐Verwendung werden in diesem Übersichtsartikel vorgestellt.
Kinetic Modeling of the Palladium‐Catalyzed Isomerizing Methoxycarbonylation of 1‐Decene
Authors: Gerlach Martin , Kirschtowski Sabine , Seidel‐Morgenstern Andreas , Hamel Christof 
Published: February 2018

AbstractThe experimental and model‐based investigation of the palladium‐catalyzed methoxycarbonylation of 1‐decene using methanol and carbon monoxide is presented. The reaction was studied in a thermomorphic solvent system using the industrially applied ligand DTBPMB in order to describe the kinetics of the main and the most relevant side reactions. Based on a reaction analysis, kinetic models including main influencing variables were derived and successfully parametrized. Thus, inhibition effects of the substrate 1‐decene as well as carbon monoxide on the isomerization and methoxycarbonylation rate could be identified.
TrpM8‐mediated somatosensation in mouse neocortex
Authors: Beukema Patrick , Cecil Katherine L. , Peterson Elena , Mann Victor R. , Matsushita Megumi , Takashima Yoshio , Navlakha Saket , Barth Alison L. 
Published: February 2018

AbstractSomatosensation is a complex sense mediated by more than a dozen distinct neural subtypes in the periphery. Although pressure and touch sensation have been mapped to primary somatosensory cortex in rodents, it has been controversial whether pain and temperature inputs are also directed to this area. Here we use a well‐defined somatosensory modality, cool sensation mediated by peripheral TrpM8‐receptors, to investigate the neural substrate for cool perception in the mouse neocortex. Using activation of cutaneous TrpM8 receptor‐expressing neurons, we identify candidate neocortical areas responsive for cool sensation. Initially, we optimized TrpM8 stimulation and determined that menthol, a selective TrpM8 agonist, was more effective than cool stimulation at inducing expression of the immediate‐early gene c‐fos in the spinal cord. We developed a broad‐scale brain survey method for identification of activated brain areas, using automated methods to quantify c‐fos immunoreactivity (fos‐IR) across animals. Brain areas corresponding to the posterior insular cortex and secondary somatosensory (S2) show elevated fos‐IR after menthol stimulation, in contrast to weaker activation in primary somatosensory cortex (S1). In addition, menthol exposure triggered fos‐IR in piriform cortex, the amygdala, and the hypothalamus. Menthol‐mediated activation was absent in TrpM8‐knock‐out animals. Our results indicate that cool somatosensory input broadly drives neural activity across the mouse brain, with neocortical signal most elevated in the posterior insula, as well as S2 and S1. These findings are consistent with data from humans indicating that the posterior insula is specialized for somatosensory information encoding temperature, pain, and gentle touch.
Integration of Enzymatic and Heterogeneous Catalysis for One‐Pot Production of Fructose from Glucose
Authors: Sun Jiankui , Li Helong , Huang Hongzhi , Wang Bo , Xiao Ling‐Ping , Song Guoyong 
Published: February 2018

AbstractThe search for efficient routes for the production of fructose from biomass‐derived glucose is of great interest and importance, as fructose is a highly attractive substrate in the conversion of cellulosic biomass into biofuels and chemicals. In this study, a one‐pot, multistep procedure involving enzyme‐catalyzed oxidation of glucose at C2 and Ni/C‐catalyzed hydrogenation of d‐glucosone at C1 selectively gives fructose in 77 % yield. Starting from upstream substrates such as α‐cellulose and starch, fructose was also generated with similar efficiency and selectivity by the combination of enzymatic and heterogeneous catalysis. This method constitutes a new means of preparing fructose from biomass‐derived substrates in an efficient fashion.