bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generation of Monolayer MoS2 with 1T Phase by Spatial‐Confinement‐Induced Ultrathin PPy Anchoring for High‐Performance Supercapacitor
Authors: Tian Yuyu , Song Xuefeng , Liu Jing , Zhao Liping , Zhang Peng , Gao Lian 
Published: April 2019

AbstractIntegrating with conducting polymer (CP) is one of the effective ways to enhance the capacitive properties for MoS2 except for the controllable preparation of ultrathin MoS2 nanosheets or appropriate phase. However, most of the MoS2/CP composites are synthesized by traditional chemical method, in which way the structural optimization of MoS2 is limited. Here, a facile electrochemical method is demonstrated to optimize MoS2 by spatial‐confinement‐induced polypyrrole (PPy) anchoring. Compared with MoS2/PPy (MP) nanocomposites synthesized by chemical method, the electrochemical prepared possesses a concomitant MoS2 monolayer, together with a transition from semiconductor phase (2H‐MoS2) to metallic phase (1T‐MoS2) during the PPy coating. Consequently, the resultant MP nanocomposite shows a remarkable capacitive performance with a high capacitance of 613 F g−1 at a current density of 1 A g−1. Meanwhile, it possesses a good rate capability that the specific capacitance retains 74%, as the current density is increased to 10 A g−1. The outstanding capacitive performance should be attributed to the existence of 1T‐MoS2 monolayer and ultrathin PPy layer as well as their effective contacts.
Cu‐Catalyzed Directed C7−H Imidation of Indolines via Cross‐Dehydrogenative Coupling
Authors: Raziullah  , Kumar Mohit , Kant Ruchir , Koley Dipankar 
Published: April 2019

AbstractCu(I)‐catalyzed C7−H imidation of indolines via cross‐dehydrogenative coupling is developed. The reaction involves C−H activation of indolines via six‐membered metallacycle and various imides were coupled with indolines, with a broad substrate scope, and functional groups tolerance. Only oxygen is required for the catalytic process. A reversible C−H bond metalation process has been observed in the preliminary mechanistic interrogation.magnified image
Silver Oxalate: Mechanical Properties and Extreme Negative Mechanical Phenomena
Authors: Colmenero Francisco 
Published: April 2019

AbstractThe crystal structure and mechanical properties of silver oxalate, Ag2C2O4, are determined using first‐principles solid‐state methods. The set of calculated mechanical properties include the bulk modulus and its pressure derivatives, the Young and shear moduli, the Poisson's Ratio and the ductility, hardness, and anisotropy indices. Silver oxalate is a highly anisotropic brittle material possessing a small bulk modulus of ≈9.6 GPa. It displays the negative Poisson's ratio (NPR) phenomenon, the value of the lowest NPR having a very large magnitude, −1.27. Besides, it exhibits the most extreme form of the negative linear compressibility (NLC) phenomenon found to date. Silver oxalate displays anisotropic NLC for external pressures in the range −0.1 to −2.4 GPa directed along the [010] crystallographic direction and isotropic NLC for isotropic pressures in the range −0.51 to 13.4 GPa. The lowest value of the negative compressibility, −831.9 ± 10 TPa−1, is found for an isotropic pressure of −0.16 GPa. The absolute value of the computed lowest NLC is extremely large, about three times larger than the absolute value of the lowest NLC found so far. The NLC pressure range is also very wide, its width being more than two times the largest range found to date.
Electrochromic Smart Windows Can Achieve an Absolute Private State through Thermochromically Engineered Electrolyte
Authors: Wang Mi , Xing Xing , Perepichka Igor F. , Shi Yuhao , Zhou Deyun , Wu Peiheng , Meng Hong 
Published: April 2019

AbstractSmart windows regulate the indoor solar radiation by adjusting their optical transmissive properties, offering an efficient way toward energy‐saving buildings, vehicles, etc. Electrochromism is one of the most promising solutions due to its simple control, versatile colors. Yet, electrochromics cannot give zero‐transmission through the whole visible range, leading to the windows that can always be looked through and limited for applications in the public sector. In this work, poly(N‐isopropylacrylamide) (PNIPAm) hydrogel, which undergoes temperature‐stimulated phase transition from a highly transparent state to a highly scattered zero‐transmission state through the whole visible range is used in the electrolyte of the electrochromic devices without affecting their electrochromic performance. It can be universally applied to inorganic and organic electrochromic devices, and the phase transition temperature can be easily tuned by the ion concentration. Therefore, apart from its ion conductive function, the electrolyte performs the chromatic transition function as well, allowing the electrochromic devices to achieve a zero‐transmissive, absolute “private” state. This chromatic engineering of the electrolyte can significantly broaden the industrial market of electrochromic smart window applications from public to private circumstances and bring much more flexibility in building façades design, which is a remarkable pavement for further industrial applications.
How Many Phosphoric Acid Units Are Required to Ensure Uniform Occlusion of Sterically Stabilized Nanoparticles within Calcite?
Authors: Douverne Marcel , Ning Yin , Tatani Aikaterini , Meldrum Fiona C. , Armes Steven P. 
Published: April 2019

AbstractPolymerization‐induced self‐assembly (PISA) mediated by reversible addition–fragmentation chain transfer (RAFT) polymerization offers a platform technology for the efficient and versatile synthesis of well‐defined sterically stabilized block copolymer nanoparticles. Herein we synthesize a series of such nanoparticles with tunable anionic charge density within the stabilizer chains, which are prepared via statistical copolymerization of anionic 2‐(phosphonooxy)ethyl methacrylate (P) with non‐ionic glycerol monomethacrylate (G). Systematic variation of the P/G molar ratio enables elucidation of the minimum number of phosphate groups per copolymer chain required to promote nanoparticle occlusion within a model inorganic crystal (calcite). Moreover, the extent of nanoparticle occlusion correlates strongly with the phosphate content of the steric stabilizer chains. This study is the first to examine the effect of systemically varying the anionic charge density of nanoparticles on their occlusion efficiency and sheds new light on maximizing the loading of guest nanoparticles within calcite host crystals.
Biocompatible SuFEx Click Chemistry: Thionyl Tetrafluoride (SOF4)‐Derived Connective Hubs for Bioconjugation to DNA and Proteins
Authors: Liu Feng , Wang Hua , Li Suhua , Bare Grant A. L. , Chen Xuemin , Wang Chu , Moses John E. , Wu Peng , Sharpless K. Barry 
Published: April 2019

AbstractWe report here the development of a suite of biocompatible SuFEx transformations from the SOF4‐derived iminosulfur oxydifluoride hub in aqueous buffer conditions. These biocompatible SuFEx reactions of iminosulfur oxydifluorides (R‐N=SOF2) with primary amines give sulfamides (8 examples, up to 98 %), while the reaction with secondary amines furnish sulfuramidimidoyl fluoride products (8 examples, up to 97 %). Likewise, under mild buffered conditions, phenols react with the iminosulfur oxydifluorides (Ar‐N=SOF2) to produce sulfurofluoridoimidates (13 examples, up to 99 %), which can themselves be further modified by nucleophiles. These transformations open the potential for asymmetric and trisubstituted linkages projecting from the sulfur(VI) center, including versatile S−N and S−O connectivity (9 examples, up to 94 %). Finally, the SuFEx bioconjugation of iminosulfur oxydifluorides to amine‐tagged single‐stranded DNA and to BSA protein demonstrate the potential of SOF4‐derived SuFEx click chemistry in biological applications.
A General Treatment to Study Molecular Complexes Stabilized by Hydrogen‐, Halogen‐, and Carbon‐Bond Networks: Experiment and Theory of (CH2F2)n⋅⋅⋅(H2O)m
Authors: Calabrese Camilla , Li Weixing , Prampolini Giacomo , Evangelisti Luca , Uriarte Iciar , Cacelli Ivo , Melandri Sonia , Cocinero Emilio J. 
Published: April 2019

AbstractRotational spectra of several difluoromethane–water adducts have been observed using two broadband chirped‐pulse Fourier‐transform microwave (CP‐FTMW) spectrometers. The experimental structures of (CH2F2)⋅⋅⋅(H2O)2, (CH2F2)2⋅⋅⋅(H2O), (CH2F2)⋅⋅⋅(H2O)3, and (CH2F2)2⋅⋅⋅(H2O)2 were unambiguously identified with the aid of 18 isotopic substituted species. A subtle competition between hydrogen, halogen, and carbon bonds is observed and a detailed analysis was performed on the complex network of non‐covalent interactions which stabilize each cluster. The study shows that the combination of stabilizing contact networks is able to reinforce the interaction strength through a cooperative effect, which can lead to large stable oligomers.
Activation of a Non‐Heme FeIII‐OOH by a Second FeIII to Hydroxylate Strong C−H Bonds: Possible Implications for Soluble Methane Monooxygenase
Authors: Kal Subhasree , Que Lawrence 
Published: April 2019

AbstractNon‐heme iron oxygenases contain either monoiron or diiron active sites, and the role of the second iron in the latter enzymes is a topic of particular interest, especially for soluble methane monooxygenase (sMMO). Herein we report the activation of a non‐heme FeIII‐OOH intermediate in a synthetic monoiron system using FeIII(OTf)3 to form a high‐valent oxidant capable of effecting cyclohexane and benzene hydroxylation within seconds at −40 °C. Our results show that the second iron acts as a Lewis acid to activate the iron–hydroperoxo intermediate, leading to the formation of a powerful FeV=O oxidant—a possible role for the second iron in sMMO.
Parametric control to linear time‐varying systems based on dynamic compensator and multi‐objective optimization
Authors: Gu Da‐Ke , Zhang Da‐Wei , Duan Guang‐Ren 
Published: April 2019

AbstractThis paper investigates the parametric approach for linear time‐variant systems by using dynamic compensator and multi‐objective optimization. Based on the solution to a class of generalized Sylvester matrix equations, the generally completely parametrized expression of the dynamic compensator is established, meanwhile, the completely parametric forms of left and right closed‐loop eigenvectors and two groups of arbitrary parameters are obtained. With the proposed parametric approach, the closed‐loop system can be transformed into a linear time‐invariant one with expected eigenstructure. Simultaneously, it also considers a novel technique to multi‐objective optimization design for linear time‐varying systems. Multiple performance objectives, including the overall sensitivity function, H2 norm and H∞ norm, are formulated by two groups of arbitrary parameters. Based on these performance objectives, the robustness criteria is expressed by a comprehensive objective function which includes each performance objective weighted. By utilizing the degrees of freedom in parameters to optimize the comprehensive objective function, an optimized dynamic compensator can be obtained to satisfy the robustness criteria. Finally, an example of spacecraft rendezvous problem is presented to illustrate the effectiveness of the proposed approach.
Stahlfaserbetonbauteile praxisgerecht berechnen, bemessen und optimieren
Authors: Look Katharina , Heek Peter , Mark Peter 
Published: April 2019

AbstractStahlfaserbetonbauteile benötigen gegenüber konventionellen Stahlbetonbauteilen besondere Methoden zur Dimensionierung. Lineare Schnittgrößenberechnungen sind meist wenig hilfreich, weil sie Tragreserven aus Umlagerungsmöglichkeiten deutlich unterschätzen. Materiell nichtlineare Berechnungen wie die Bruchlinientheorie bieten sich an. Für die Bemessung ist der aus der Faserwirkung additiv entstehende Zuganteil einzubeziehen, was gesonderte Ansätze und Verfahren zur Gleichgewichtsiteration erfordert. Die Fasertragwirkung wird dabei als Eingangswert über Leistungsklassen gewählt und nicht etwa wie bei klassischen Bemessungen als Ergebnis bestimmt. Es bleibt dann unklar, ob die a priori getroffene Wahl wirklich wirtschaftlich war. Der Beitrag stellt dazu eine gekoppelte Lösungsstrategie vor. Sie nutzt zunächst wirtschaftliche, nichtlineare Schnittgrößenermittlungen. Auf Querschnittsebene werden die Schnittgrößen zur Biege‐ und Querkraftbemessung von beliebig bewehrten Rechteckquerschnitten verwendet. Angeschlossen ist dabei auch die Rissbreitenbeschränkung. Letzter Schritt ist die rückwärtsgerichtete Optimierung der Faserklassen, welche die Leistungsklassen in Wertung der Bemessungsergebnisse auf tatsächlich nötige Größen reduziert. Das gekoppelte Verfahren ist in einem intuitiv nutzbaren Tabellenkalkulationsprogramm implementiert, welches zum freien Download zur Verfügung steht. Beispiele zeigen die Anwendung und Konsequenzen für die Praxis.
Deutschlandweit erstmalige Anwendung von UHPFRC im Eisenbahnbrückenbau
Authors: Schramm Nicholas , Fischer Oliver 
Published: April 2019

AbstractUltrahochfester faserbewehrter Beton (UHPFRC) zeichnet sich durch ein extrem dichtes Gefüge und sehr hohe Festigkeiten sowie exzellente Dauerhaftigkeitseigenschaften aus. Dadurch wird eine langlebige, materialsparende und gewichtsreduzierte, schlanke Bauweise realisierbar, die völlig neue Möglichkeiten und Einsatzbereiche im Fertigteil‐Brückenbau eröffnet. Im Zuge der Überbauerneuerung einer bestehenden Bahnbrücke konnte der Werkstoff nun in Deutschland erstmalig für eine Eisenbahnbrücke besonders zweckmäßig und vorteilhaft eingesetzt werden. Das Brückenbauwerk wurde als Fertigteil‐Plattenbrücke mit Trogquerschnitt in Spannbetonbauweise mit sehr geringer Konstruktionshöhe realisiert. Der vorliegende Teil 2 des Beitrags behandelt zum einen begleitende experimentelle Untersuchungen zur Rissbildung und zum Biegetragverhalten eines rein stahlfaserbewehrten Mock‐up des Brückenüberbaus. Zum anderen geht der Fachaufsatz auf die messtechnische Begleitung der Herstellung und des Betriebs ein. Hierbei wurden neben der Erfassung von Verlusten der Vorspannung und der Hydratationswärmeentwicklung unter anderem auch Bauwerksmessungen zur Ermittlung der realen Tragwerksantworten im Zuge von Probebelastungen mit definierten Achslasten durchgeführt.
Transcriptome and proteome analysis of steady‐state in a perfusion CHO cell culture process
Authors: Bertrand Vania , Karst Daniel J. , Bachmann Alessia , Cantalupo Katia , Soos Miroslav , Morbidelli Massimo 
Published: April 2019

AbstractLong‐term continuous protein production can be reached by perfusion operation. Through the continuous removal of waste metabolites and supply of nutrients, steady‐state (SS) conditions are achieved after a certain transient period, where the conditions inside the reactor are not only uniform in space but also constant in time. Such stable conditions may have beneficial influences on the reduction of product heterogeneities. In this study, we investigated the impact of perfusion cultivation on the intracellular physiological state of a CHO cell line producing a monoclonal antibody (mAb) by global transcriptomics and proteomics. Despite stable viable cell density was maintained right from the beginning of the cultivation time, productivity decrease, and a transition phase for metabolites and product quality was observed before reaching SS conditions. These were traced back to three sources of transient behaviors being hydrodynamic flow rates, intracellular dynamics of gene expression as well as metabolism and cell line instability, superimposing each other. However, 99.4% of all transcripts and proteins reached SS during the first week or were at SS from the beginning. These results demonstrate that the stable extracellular conditions of perfusion lead to SS also of the cellular level.
Cell‐Penetrating Peptide Foldamers: Drug‐Delivery Tools
Authors: Oba Makoto 
Published: April 2019

AbstractHighly efficient drug‐delivery tools for membrane‐impermeable compounds, proteins, and nucleic acids in living cells are useful in the fields of chemical biology and drug discovery, and such tools have been widely studied. One strategy in the development of novel drug‐delivery tools is to utilize cell‐penetrating peptide (CPP) foldamers. CPP foldamers are folded oligopeptides that possess cell membrane permeability. In recent decades, a wide variety of CPP foldamers have been reported by many groups. Herein, CPP foldamers are introduced and discussed from the viewpoints of component monomers (amino acids) and their application as drug‐delivery tools.
N‐Doped Hierarchical Porous Carbon Embedded Synergistic Bimetallic CoCu NPs with Unparalleled Catalytic Performance
Authors: Zhang Fengwei , Li Zhihong , Ma Chunlan , Han Xu , Dong Xue , Dong Zhengping , Zhang Xian‐Ming 
Published: April 2019

AbstractBy virtue of the structural diversity, electronic tunability and synergetic effect, heterogeneous non‐noble bimetallic catalysts have demonstrated excellent catalytic performance in Fischer‐Tropsch synthesis, biomass conversion and fine chemicals synthesis community. However, the feature of synergetic effect and formation mechanism of bimetallic CoCu NPs under carbothermal conditions still remain to be explored. Herein we report an efficient protocol for fabrication of a representative N‐doped hierarchical porous carbon embedding bimetallic CoCu NPs catalyst. Particularly, the prepared Co0.7Cu0.3@NHPC‐800 catalyst demonstrates unprecedented catalytic activity and chemoselectivity for various nitroaromatics under extremely mild condition (1 atm H2, 30 °C), which is superior to the existing non‐noble metal‐based catalytic systems. It also exhibits excellent activity for hydrolysis of ammonia borane in pure water at room temperature. Furthermore, the possible formation process of bimetallic NPs is firstly brought to light, which could be the key to the nature of CoCu synergistic effect as well as the resultant high activity and selectivity.
Hierarchically Pomegranate‐Like MnO@porous Carbon Microspheres as an Enhanced‐Capacity Anode for Lithium‐Ion Batteries
Authors: Gao Ming , Huang Shouji , Zhang Qi , Xu Guobao , Chen Zhuo , Xiao Yufeng , Yang Liwen , Cao Juexian , Wei Xiaolin 
Published: April 2019

AbstractTransition‐metal oxides have attracted much attention as promising anode materials, owing to high theoretical specific capacity for lithium‐ion batteries (LIBs). However, rapid performance degradation derived from poor electrical conductivity and drastic volume changes during the repeated lithium insertion/extraction processes has limited their practical applications. In this work, we design and prepare pomegranate‐like microspheres of nano‐sized MnO particles with gaps among them as the core and porous carbon as the shell (designated as PCMS@MnO) by using a facile three‐step process. In such unique PCMS@MnO, the porous carbon shell from phenolic resin is beneficial for the electronic conductivity and wettability, whereas the nano‐sized MnO particles with gaps among them confined in the porous carbon shell can effectively prevent aggregation and pulverization of active materials. As an anode material for LIBs, the PCMS@MnO with a carbon content of about 12 wt % exhibits remarkably high reversible capability (935 mAh g−1 at 100 mA g−1), outstanding rate performance, and superior cycling stability (527 mAh g−1 of 2000 mA g−1 after 2000 cycles). Our results suggest a great potential of pomegranate‐like transition‐metal oxide‐based composites as anode materials in high‐performance LIBs.
DEGINTU – A Free Management System of Risk Evaluation in Science Education
Authors: Lüke Dennis , Friedrich Jens 
Published: April 2019

AbstractDas Erstellen von Gefährdungsbeurteilungen, der Ersatzstoffprüfung sowie deren Dokumentation beim Experimentieren ist mit der RiSU 2003 für Lehrkräfte im naturwissenschaftlichen Unterricht verpflichtend geworden. Im Beitrag wird die Online‐Datenbank DEGINTU vorgestellt, die eine Gefahrstoffdatenbank auf Basis der GESTIS‐Stoffdatenbank beinhaltet und eine Chemikalienverwaltung ermöglicht. Darüber hinaus lassen sich rechtskonforme Gefährdungsbeurteilungen kostenlos herunterladen. Die Erstellung einer Gefährdungsbeurteilung wird am Beispiel einer Hybrid‐Redox‐Flow‐Zelle aufgezeigt.
G‐SERF Editing in Two‐Dimensional Pure‐Shift Total Correlation Spectroscopy: Scalar Coupling Measurements for a Group of Spins in Organic Molecules
Authors: Rao Kakita Veera Mohana , Joshi Mamata V , Hosur Ramakrishna V 
Published: April 2019

AbstractA novel G‐SERF‐PSYCHE‐TOCSY (gradient encoded selective refocusing in pure shift yielded by chirp excitation version of total correlation spectroscopy) NMR pulse scheme has been proposed, which produces TOCSY chemical shift correlations, on one hand, and scalar coupling values for the spins scalarly coupled to irradiated resonances, by showing them as doublets along the indirect dimension, on the other. Therefore, recording such an experiment, for a group of spins with overlapping chemical shifts, in organic molecules can adequately provide scalar coupling information in a G‐SERF manner along the indirect dimensions, and they can be assigned to particular spin pairs. Such COSY chemical shift correlations (which appear as doublets for the scalarly coupled spins) can be readily discriminated from the TOCSY peaks (which do not show such splitting) in the G‐SERF‐PSYCHE‐TOCSY spectrum.
Cosolvent and Crowding Effects on the Temperature‐ and Pressure‐Dependent Dissociation Process of the α/β‐Tubulin Heterodimer
Authors: Schummel Paul Hendrik , Anders Christian , Jaworek Michel W. , Winter Roland 
Published: April 2019

AbstractThe front cover artwork illustrates that by adjusting the level of natural cosolutes like TMAO, the deteriorating effect of deep‐sea hydrostatic pressures on tubulin association can be suppressed. Read the full text of the Article at 10.1002/cphc.201900115.
Towards a better sensor data accuracy via quality of monitoring and semantic clustering
Authors: G. S. Campos Nidia , R. Rocha Atslands , G. Gomes Danielo 
Published: April 2019

SummarySemantic clustering organizes wireless sensor nodes in clusters to detect a relevant event for an application. These nodes send only a message reporting it to the sink node while the other nodes decrease their resource utilization to save energy. In this work, we enhance semantic clustering with quality of monitoring (QoM) attributes of the event detection probability with variance reduction or dissimilarity measure. This approach allows each node to evaluate the accuracy of detection and the correlation level of the data gathered locally and by its neighbors. Experiments in a WLAN and FIT/IoT‐Lab show QoM attributes improve the accuracy, especially in an extensive network where dissimilarity measure can keep it high independently of the cluster size. QoM also increases the sampling of these events by up to 60.7% while it decreases the number of messages sent to the sink between 13.1% and 32.9% without affecting the cluster formation or power consumption in almost all experiments.