bluuebunny/crossref_metadata_2025_split huggingface dataset:
Covalent Organic Framework Electrocatalysts for Clean Energy Conversion
Authors: Lin Chun‐Yu , Zhang Detao , Zhao Zhenghang , Xia Zhenhai 
Published: November 2017

AbstractCovalent organic frameworks (COFs) are promising for catalysis, sensing, gas storage, adsorption, optoelectricity, etc. owning to the unprecedented combination of large surface area, high crystallinity, tunable pore size, and unique molecular architecture. Although COFs are in their initial research stage, progress has been made in the design and synthesis of COF‐based electrocatalysis for the oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, and CO2 reduction in energy conversion and fuel generation. Design principles are also established for some of the COF materials toward rational design and rapid screening of the best electrocatalysts for a specific application. Herein, the recent advances in the design and synthesis of COF‐based catalysts for clean energy conversion and storage are presented. Future research directions and perspectives are also being discussed for the development of efficient COF‐based electrocatalysts.
Self‐Assembled Hybrid Materials Based on Organic Nanocrystals and Carbon Nanotubes
Authors: Niazov‐Elkan Angelica , Weissman Haim , Dutta Sounak , Cohen Sidney R. , Iron Mark A. , Pinkas Iddo , Bendikov Tatyana , Rybtchinski Boris 
Published: November 2017

AbstractOrganic crystalline materials are used as dyes/pigments, pharmaceuticals, and active components of photonic and electronic devices. There is great interest in integrating organic crystals with inorganic and carbon nanomaterials to create nanocomposites with enhanced properties. Such efforts are hampered by the difficulties in interfacing organic crystals with dissimilar materials. Here, an approach that employs organic nanocrystallization is presented to fabricate solution‐processed organic nanocrystal/carbon nanotube (ONC/CNT) hybrid materials based on readily available organic dyes (perylene diimides (PDIs)) and carbon nanotubes. The hybrids are prepared by self‐assembly in aqueous media to afford free‐standing films with tunable CNT content. These exhibit excellent conductivities (as high as 5.78 ± 0.56 S m−1), and high thermal stability that are superior to common polymer/CNT hybrids. The color of the hybrids can be tuned by adding various PDI derivatives. ONC/CNT hybrids represent a novel class of nanocomposites, applicable as optoelectronic and conductive colorant materials.
Functionalized 2D Clay Derivative: Hybrid Nanosheets with Unique Lead Sorption Behaviors and Interface Structure
Authors: Yan Zhaoli , Fu Liangjie , Yang Huaming 
Published: November 2017

AbstractClay mineral and its derivatives can play an important role in stabilizing functional‐groups and nanostructures. Here, a TP‐SiNSs (TiSi2O5(OH)2·(OH2)2) nanocomposite, with highly dispersed and stabilized TiO2 precursor (TP, Ti(OH)4 gel) on template‐free 2D silica nanosheets (SiNSs, Si2O3(OH)2), is presented, which is derived from kaolinite, a natural 2D layer mineral. Unique lead sorption behaviors are observed for balanced hydrophobicity–hydrophilicity, short sorption equilibrium time (within 5 min), large applied sorption capacities (≈38 000 kg polluted drinking water per kg TP‐SiNSs, effluent Pb(II) contents <10 µg L−1), and excellent renewability. The highly dispersed surface titanium hydroxyl groups, together with 2D hierarchical porous nanostructure of TP‐SiNSs effectively facilitate the selective adsorption of Pb(II) ions, inhibit the pore blockage after Pb(II) adsorption, and prolong the service life. The detailed adsorption mechanism as a function of pH value and ion concentration is clarified by density functional theory (DFT) calculations, and the higher adsorption selectivity of TP‐SiNSs for Pb(II) over Ca(II) and Mg(II) is attributed to surface complex on TP‐SiNSs, which induces strong bonding between Pb(II) and titanium hydroxyl groups. The interface geometry and electronic structure calculations demonstrate that the stabilized and spatially distributed titanium hydroxyl group on TP‐SiNSs can greatly enhance the surface adsorption ability.
Effects of W/Ir Top Electrode on Resistive Switching and Dopamine Sensing by Using Optimized TaOx‐Based Memory Platform
Authors: Samanta Subhranu , Maikap Siddheswar , Roy Anisha , Jana Surajit , Qiu Jian‐Tai 
Published: November 2017

AbstractResistive switching with best structural optimization by taking 100 devices of each structure including tungsten/iridium (W/Ir) top electrode effects and dopamine sensing by inserting 2 nm thick Al2O3 interfacial layer in TaOx‐based memory platform are reported for the first time. Statistical analysis of device‐to‐device switching uniformity for the formation voltage, low resistance state, and high resistance state is executed at low current compliance of 30 μA by inserting 2 nm thick Al2O3 layer underneath of W electrode in W/Al2O3/TaOx/TiN structure. Incorporation of defective layer (TaOx) into Ta2O5 layer is clearly observed from the high‐resolution transmission electron microscope image of stressed device. A long program/erase endurance of >108 cycles under low current of 30 μA with pulse width of 100 ns and retention of >900 h at 85 °C is obtained. Diode‐like rectifying at 1 μA with higher ratio of >5000, nonlinearity factor of >300, and complementary resistive switching are achieved by using Ir electrode. Transport mechanism is dominated by Schottky conduction. Dopamine at a low concentration of 1 × 10−12m is detected through porous Ir in Ir/Al2O3/TaOx/TiN structure owing to oxidation at the Ir/Al2O3 interface for the first time, which will be useful for early diagnosis of human diseases.
Strain‐Induced Rolled Thin Films for Lightweight Tubular Thermoelectric Generators
Authors: Singh Devendra , Kutbee Arwa T. , Ghoneim Mohamed T. , Hussain Aftab M. , Hussain Muhammad M. 
Published: November 2017

AbstractThermoelectric generators (TEGs) are interesting energy harvesters of otherwise wasted heat. Here, a polymer‐assisted generic process and its mechanics to obtain sputtered thermoelectric (TE) telluride material‐based 3D tubular structures with unprecedented length (up to seamless 4 cm and further expandable) are shown. This length allows for large temperature differences between the hot and the cold ends, a critical but untapped enabler for high power generation. Compared with a flat slab, better area efficiency is observed for a rolled tube and compared with a solid rod architecture, a rolled tube uses less material (thus making it lightweight and cost effective) and has competitive performance advantage due to a smaller contact area. It is also shown that a tubular architecture thermopile‐based TEG is able to generate up to 5 μW of power (eight pairs of p‐ and n‐type thermopiles) through a temperature difference of 60 °C. The demonstrated process can play an important role in transforming 2D atomic crystal structure TE materials into 3D tubular thermopiles for effective TEG application, which can maintain higher temperature differences by longer distances between hot and cold ends.
Direct Exfoliation of High‐Quality, Atomically Thin MoSe2 Layers in Water
Authors: Liu Yi‐Tao , Zhu Xiao‐Dong , Xie Xu‐Ming 
Published: November 2017

AbstractThe discovery of 2D materials has brought us to a conceptually new, wonderful microscopic world. Large surface areas combined with extraordinary electronic, electrochemical, and thermal properties make these atomically thin, layered materials fascinating candidates for diverse applications, ranging from sensing to energy storage and electrocatalytic hydrogen evolution. However, it is essential to solve the problem of scalable and green production of 2D materials before being able to bring them from laboratory to industry. In this sense, the exfoliation of 2D materials in water, free from any stabilizer, is very important since it is a gateway technology toward their production as well as future applications. This Communication reports the direct exfoliation of atomically thin MoSe2 layers in water, which bypasses the Hansen solubility parameters theory and suggests potential for liquid‐phase exfoliation of 2D materials. A combination of long‐time sonication and high‐speed centrifugation results in a substantial fraction of monolayers. When applied in the field of electrocatalytic hydrogen evolution, these atomically thin MoSe2 layers can significantly outperform bulk MoSe2. The finding may point towards industrial scale production of 2D materials by simultaneously ensuring high product quality, laudable monolayer yield, and good environmental compatibility.
Thermal stability, fire behavior, and fumes emission of polyethylene nanocomposites with halogen‐free fire retardants
Authors: Sałasińska Kamila , Borucka Monika , Celiński Maciej , Gajek Agnieszka , Zatorski Wojciech , Mizera Kamila , Leszczyńska Milena , Ryszkowska Joanna 
Published: November 2017

AbstractThe synergism between nanoparticles and different kinds of halogen‐free fire retardants leading to reduction in flammability and smoke generation of polyethylene was investigated. The composites were evaluated by thermogravimetric analysis, oxygen index test, cone calorimeter measurements, and a single‐chamber test. Moreover, the semivolatile and volatile compounds evolved in the thermal degradation processes of polyethylene were determined using a steady state tube furnace and gas chromatograph with mass spectrometer. Morphological and structural characteristics as well as thermomechanical properties of the composites were characterized using various techniques including scanning electron microscopy (SEM), X‐ray diffraction (XRD), and dynamic mechanical thermal analysis (DMTA). The obtained data were compared to the results received for polyethylene and polymer with bromine‐containing fire retardants. The incorporation of nanofillers and halogen‐free fire retardants caused a reduction in combustibility as a consequence of the formation of char. Furthermore, the presence of nanoparticles has a beneficial effect on the inhibition of dripping. The polyethylene with carbon nanotubes, zinc borate, and aluminum hydroxide exhibited better combined properties of fire behavior and production of nontoxic smoke compared to the remaining composition and reference materials.
3D‐Bioprinted Osteoblast‐Laden Nanocomposite Hydrogel Constructs with Induced Microenvironments Promote Cell Viability, Differentiation, and Osteogenesis both In Vitro and In Vivo
Authors: Zhai Xinyun , Ruan Changshun , Ma Yufei , Cheng Delin , Wu Mingming , Liu Wenguang , Zhao Xiaoli , Pan Haobo , Lu William Weijia 
Published: November 2017

AbstractAn osteoblast‐laden nanocomposite hydrogel construct, based on polyethylene glycol diacrylate (PEGDA)/laponite XLG nanoclay ([Mg5.34Li0.66Si8O20(OH)4]Na0.66, clay)/hyaluronic acid sodium salt (HA) bio‐inks, is developed by a two‐channel 3D bioprinting method. The novel biodegradable bio‐ink A, comprised of a poly(ethylene glycol) (PEG)–clay nanocomposite crosslinked hydrogel, is used to facilitate 3D‐bioprinting and enables the efficient delivery of oxygen and nutrients to growing cells. HA with encapsulated primary rat osteoblasts (ROBs) is applied as bio‐ink B with a view to improving cell viability, distribution uniformity, and deposition efficiency. The cell‐laden PEG–clay constructs not only encapsulated osteoblasts with more than 95% viability in the short term but also exhibited excellent osteogenic ability in the long term, due to the release of bioactive ions (magnesium ions, Mg2+ and silicon ions, Si4+), which induces the suitable microenvironment to promote the differentiation of the loaded exogenous ROBs, both in vitro and in vivo. This 3D‐bioprinting method holds much promise for bone tissue regeneration in terms of cell engraftment, survival, and ultimately long‐term function.
Vulnerable voices on fire preparedness: Policy implications for emergency and community services collaboration
Authors: Ingham Valerie , Redshaw Sarah 
Published: November 2017

AbstractAn investigation of household preparedness and community connections was undertaken in the NSW Blue Mountains. The research employed a qualitative approach. Upon receiving ethical approval, interviews and focus groups with a total of 31 vulnerable residents were recorded and transcribed. Data analysis included the manual coding of individual transcripts and key word queries entered into NVivo 10. Fire planning for community resilience within Australia focusses on property preparation and an emergency warning system designed to assist the evacuation decisions of residents. In this article, we report on vulnerable residents and their preparedness for the October 2013 bushfires. Our findings demonstrate that the vulnerable people interviewed did not consider property preservation as a priority, and their knowledge and engagement with the warning system and evacuation procedures was limited. Of practical value, the research found local community services and emergency planning committees should collaboratively plan for vulnerable community members who are unable to take a very active role in preparing themselves or their dependents to face a bushfire or similar disaster. In addition, preparedness and warning communications should be devised and targeted to more clearly assist vulnerable people during the lead up to, and in the midst of, a disaster.
Targeting hypersensitive corticostriatal terminals in restless legs syndrome
Authors: Yepes Gabriel , Guitart Xavier , Rea William , Newman Amy H. , Allen Richard P. , Earley Christopher J. , Quiroz César , Ferré Sergi 
Published: November 2017

ObjectiveThe first aim was to demonstrate a previously hypothesized increased sensitivity of corticostriatal glutamatergic terminals in the rodent with brain iron deficiency (BID), a pathogenetic model of restless legs syndrome (RLS). The second aim was to determine whether these putative hypersensitive terminals could constitute a significant target for drugs effective in RLS, including dopamine agonists (pramipexole and ropinirole) and α2δ ligands (gabapentin).MethodsA recently introduced in vivo optogenetic–microdialysis approach was used, which allows the measurement of the extracellular concentration of glutamate upon local light‐induced stimulation of corticostriatal glutamatergic terminals. The method also allows analysis of the effect of local perfusion of compounds within the same area being sampled for glutamate.ResultsBID rats showed hypersensitivity of corticostriatal glutamatergic terminals (lower frequency of optogenetic stimulation to induce glutamate release). Both hypersensitive and control glutamatergic terminals were significant targets for locally perfused pramipexole, ropinirole, and gabapentin, which significantly counteracted optogenetically induced glutamate release. The use of selective antagonists demonstrated the involvement of dopamine D4and D2receptor subtypes in the effects of pramipexole.InterpretationHypersensitivity of corticostriatal glutamatergic terminals can constitute a main pathogenetic mechanism of RLS symptoms. Selective D4receptor agonists, by specifically targeting these terminals, should provide a new efficient treatment with fewer secondary effects. Ann Neurol 2017;82:951–960
Increasing motor neuron excitability to treat weakness in sepsis
Authors: Nardelli Paul , Powers Randall , Cope Tim C. , Rich Mark M. 
Published: November 2017

ObjectiveWeakness induced by critical illness (intensive care unit acquired weakness) is a major cause of disability in patients and is currently untreatable. We recently identified a defect in repetitive firing of lower motor neurons as a novel contributor to intensive care unit acquired weakness. To develop therapy for intensive care unit acquired weakness, it was necessary to determine the mechanism underlying the defect in repetitive firing.MethodsBoth computer simulation and in vivo dynamic voltage clamp of spinal motor neurons in septic rats were employed to explore potential mechanisms underlying defective repetitive firing.ResultsOur results suggest alteration in subthreshold voltage‐activated currents might be the mechanism underlying defective repetitive firing. It has been shown previously that pharmacologic activation of serotonin receptors on motor neurons increases motor neuron excitability, in part by enhancing subthreshold voltage‐activated inward currents. Administration of a U.S. Food and Drug Administration–approved serotonin agonist (lorcaserin) to septic rats greatly improved repetitive firing and motor unit force generation.InterpretationOur findings suggest activation of serotonin receptors with lorcaserin may provide the first ever therapy for intensive care unit acquired weakness in patients. Ann Neurol 2017;82:961–971
Clinical and genetic findings in children with central nervous system arteriovenous fistulas
Authors: Saliou Guillaume , Eyries Mélanie , Iacobucci Marta , Knebel Jean‐François , Waill Marie‐Christine , Coulet Florence , Ozanne Augustin , Soubrier Florent 
Published: November 2017

ObjectiveTo assess the spectrum of genetic anomalies in a cohort of children presenting at least one cerebral or spinal pial arteriovenous fistula (AVF), and to describe their clinical characteristics.MethodsFrom 1988 to 2016, all consecutive patients with at least one cerebral or spinal pial AVF were screened for genetic disease. All patients aged <18 years were included. Symptoms associated with AVF were recorded: heart failure, neurological deficit/seizure, and hemorrhage. The outcome was assessed using the modified Rankin Scale and school performance in children with cerebral AVF and the American Spinal Injury Association impairment scale in children with spinal AVF.ResultsForty‐three children were included. Twenty‐five children were male and 18 were female. A germline mutation was identified in 23 probands (53.5 ± 14.9%): 8 in ENG (34.8 ± 14.2%), 1 in ACVRL1 (4.3 ± 6%) leading to a diagnosis of HHT, and 14 in RASA1 (60.9 ± 14.4%) leading to a diagnosis of capillary malformation/arteriovenous malformation type 1. No EphB4 gene mutation was identified. HHT patients presented a significantly lower rate of heart failure at diagnosis (p = 0.047). A trend toward an increased bleeding rate at presentation was observed in HHT (p = 0.069) and an increased rate of giant venous pouch in children in whom no mutation was identified (p = 0.097). Finally, an association with RASA1 mutation was observed in children with associated skin capillary hemangioma (p <  0001).InterpretationThese results highlight the importance of genetic testing in this setting in view of the high frequency of gene mutations in pediatric cerebrospinal AVFs, and show the predominance of RASA1 over HHT mutations. Ann Neurol 2017;82:972–980
Enantioselective Synthesis ofN,S‐Acetals by an Oxidative Pummerer‐Type Transformation using Phase‐Transfer Catalysis
Authors: Biswas Souvagya , Kubota Koji , Orlandi Manuel , Turberg Mathias , Miles Dillon H. , Sigman Matthew S. , Toste F. Dean 
Published: November 2017

AbstractReported is the first enantioselective oxidative Pummerer‐type transformation using phase‐transfer catalysis to deliver enantioenriched sulfur‐bearing heterocycles. This reaction includes the direct oxidation of sulfides to a thionium intermediate, followed by an asymmetric intramolecular nucleophilic addition to form chiral cyclicN,S‐acetals with moderate to high enantioselectivites. Deuterium‐labelling experiments were performed to identify the stereodiscrimination step of this process. Further analysis of the reaction transition states, by means of multidimensional correlations and DFT calculations, highlight the existence of a set of weak noncovalent interactions between the catalyst and substrate that govern the enantioselectivity of the reaction.
Intramolecular Acetyl Transfer to Olefins by Catalytic C−C Bond Activation of Unstrained Ketones
Authors: Rong Zi‐Qiang , Lim Hee Nam , Dong Guangbin 
Published: November 2017

AbstractA rhodium‐catalyzed intramolecular acetyl‐group transfer has been achieved through a “cut and sew” process. The challenge arises from the existence of different competitive pathways. Preliminary success has been achieved with unstrained enones that contain a biaryl linker. The use of an electron‐rich N‐heterocycilc carbene (NHC) ligand is effective to inhibit undesired β‐hydrogen elimination. Various 9,10‐dihydrophenanthrene derivatives can be prepared with excellent functional‐group compatibility. The 13C‐labelling study suggests that the reaction begins with cleavage of the unstrained C−C bond, followed by migratory insertion and reductive elimination.
Basic Remarks on Acidity
Authors: Himmel Daniel , Radtke Valentin , Butschke Burkhard , Krossing Ingo 
Published: November 2017

AbstractThis Review provides a unified view on Brønsted acidity. For this purpose, a brief overview of the concepts acidity, acid strengths, and pH value is given, including problems, proposed solutions, and the use of the pHabs/
scale as a unifying concept. Thereafter, some examples of the accessibility and application of unified pHabs values are given. The Review is rounded off with the analogy of acid‐base chemistry to redox chemistry with the introduction of the unified redox scale peabs. The combination of pHabs and peabs values in the protoelectric potential map (PPM), as elaborated in ongoing studies on the thermochemistry of single ions, provides a means to classify and to compare all possible acid‐base/redox reactions in a medium‐independent and, thus, unified fashion.
The Long‐Term Stability of KO2 in K‐O2 Batteries
Authors: Xiao Neng , Rooney Ryan T. , Gewirth Andrew A. , Wu Yiying 
Published: November 2017

AbstractThe rechargeable K‐O2 battery is recognized as a promising energy storage solution owing to its large energy density, low overpotential, and high coulombic efficiency based on the single‐electron redox chemistry of potassium superoxide. However, the reactivity and long‐term stability of potassium superoxide remains ambiguous in K‐O2 batteries. Parasitic reactions are explored and the use of ion chromatography to quantify trace amounts of side products is demonstrated. Both quantitative titrations and differential electrochemical mass spectrometry confirm the highly reversible single‐electron transfer process, with 98 % capacity attributed to the formation and decomposition of KO2. In contrast to the Na‐O2 counterparts, remarkable shelf‐life is demonstrated for K‐O2 batteries owing to the thermodynamic and kinetic stability of KO2, which prevents the spontaneous disproportionation to peroxide. This work sheds light on the reversible electrochemical process of K++e−+O2↔KO2.
A Sterically Constrained Tricyclic PC3 Phosphine: Coordination Behavior and Insertion of Chalcogen Atoms into P−C Bonds
Authors: Hentschel Anne , Brand Alexander , Wegener Philipp , Uhl Werner 
Published: November 2017

AbstractA tricyclic phosphine has been generated that has a rigid molecular backbone with the P atoms exclusively bound to C(sp2) atoms as well as a very large Tolman angle and buried volume. It is an interesting new ligand in coordination chemistry (Au, Pd complexes) and shows unusual insertion reactions into its endocyclic P−C bonds facilitated by its inherent molecular strain.