bluuebunny/crossref_metadata_2025_split huggingface dataset:
Challenges in Developing Electrodes, Electrolytes, and Diagnostics Tools to Understand and Advance Sodium‐Ion Batteries
Authors: Xu Gui‐Liang , Amine Rachid , Abouimrane Ali , Che Haiying , Dahbi Mouad , Ma Zi‐Feng , Saadoune Ismael , Alami Jones , Mattis Wenjuan Liu , Pan Feng , Chen Zonghai , Amine Khalil 
Published: February 2018

AbstractConsidering the natural abundance and low cost of sodium resources, sodium‐ion batteries (SIBs) have received much attention for large‐scale electrochemical energy storage. However, smart structure design strategies and good mechanistic understanding are required to enable advanced SIBs with high energy density. In recent years, the exploration of advanced cathode, anode, and electrolyte materials, as well as advanced diagnostics have been extensively carried out. This review mainly focuses on the challenging problems for the attractive battery materials (i.e., cathode, anode, and electrolytes) and summarizes the latest strategies to improve their electrochemical performance as well as presenting recent progress in operando diagnostics to disclose the physics behind the electrochemical performance and to provide guidance and approaches to design and synthesize advanced battery materials. Outlook and perspectives on the future research to build better SIBs are also provided.
Elucidation of the Sodium‐Storage Mechanism in Hard Carbons
Authors: Bai Panxing , He Yongwu , Zou Xiaoxi , Zhao Xinxin , Xiong Peixun , Xu Yunhua 
Published: February 2018

AbstractHard carbons (HCs) are the most promising candidate anode materials for emerging Na‐ion batteries (NIBs). HCs are composed of misaligned graphene sheets with plentiful nanopores and defects, imparting a complex correlation between its structure and sodium‐storage behavior. The currently debated mechanism of Na+‐ion insertion in HCs hinders the development of high‐performance NIBs. In this article, ingenious and reliable strategies are used to elaborate the correlation between the structure and electrochemical performance and further illuminate the sodium‐storage mechanism in HCs. First, filling sulfur into the micropores of HCs can remove the low‐voltage plateau, providing solid evidence for its association with the pore‐filling mechanism. Along with the decreased concentration of defects/heteroatoms at higher treatment temperature, the reduced sloping capacity confirms the adsorption mechanism in the sloping region. Finally, the similar sodium‐insertion behaviors of HCs with ether‐based and ester‐based electrolytes indicate that no Na+ ions intercalate between the graphene layers. The determined adsorption‐pore‐filling mechanism encourages the design of more efficient HC anode materials with high capacity for high‐energy NIBs.
The Role of Active Oxide Species for Electrochemical Water Oxidation on the Surface of 3d‐Metal Phosphides
Authors: Liu Kaili , Wang Fengmei , He Peng , Shifa Tofik Ahmed , Wang Zhenxing , Cheng Zhongzhou , Zhan Xueying , He Jun 
Published: February 2018

AbstractTransition metal phosphides (TMPs) have recently been utilized as promising electrocatalysts for oxygen evolution reaction (OER) in alkaline media. The metal oxides or hydroxides formed on their surface during the OER process are hypothesized to play an important role. However, their exact role is yet to be elucidated. Here unambiguous justification regarding the active role of oxo(hydroxo) species on O‐Ni(1−x)FexP2 nanosheet with pyrite structure is shown. These O‐Ni(1−x)FexP2 (x = 0.25) nanosheets demonstrate greatly improved OER performance than their corresponding hydroxide and oxide counterparts do. From density function theory (DFT) calculations, it is found that the introduction of iron into the pyrite‐phased NiP2 alters OER steps occurred on the surface. Notably, the partially oxidized surface of O‐Ni(1−x)FexP2 nanosheets is vital to improve the local environment and accelerate the reaction steps. This study sheds light on the OER mechanism of the 3d TMP electrocatalyst and opens up a way to develop efficient and low‐cost electrocatalysts.
Potential role for emergency physicians with endoscopy training in the treatment of upper gastrointestinal hemorrhage: a retrospective observational study
Authors: Kobe Yoshiro , Oami Takehiko , Hashida Tomoaki , Tateishi Yoshihisa 
Published: February 2018

AimUrgent endoscopy is essential in gastrointestinal (GI) bleeding. Emergency physicians with endoscopy training treat patients with GI bleeding in our hospital. We compared the management and clinical outcomes of GI bleeding cases between those treated by an emergency physician (EP) and those treated by a non‐emergency physician (NEP; e.g., gastroenterologist or general surgeon).MethodsWe undertook a retrospective chart review of upper GI bleeding cases treated using endoscopy in the emergency department between 2012 and 2014. We examined patients characteristics, endoscopic findings, hemostatic procedures, need for transfusion, rebleeding and adverse events, length of hospital stay, and mortality.ResultsThe EP group included 33 patients (39%) and the NEP group included 51 (61%). Patient characteristics and diseases did not differ between the groups. The EP group underwent urgent endoscopy more often (100% versus 86%, P = 0.04). Procedure times were not statistically different between the groups. The EP group had fewer hemostatic procedures (42% versus 65%, P = 0.04). Transfusion requirements were lower in the EP group (0.5 U versus 2.1 U, P = 0.006). There were no statistical differences in rebleeding and adverse events. The length of hospital stay was shorter (8 versus 11 days, P = 0.03) and the in‐hospital mortality rate was lower in the EP group (0% versus 13.7%, P = 0.04).ConclusionShort‐term outcomes in GI bleeding cases managed by emergency physicians with endoscopy training were comparable to those by gastroenterologists and general surgeons. However, the extent of endoscopic training and experience emergency physicians should have remains unclear.
Barium as Honorary Transition Metal in Action: Experimental and Theoretical Study of Ba(CO)+ and Ba(CO)−
Authors: Wu Xuan , Zhao Lili , Jiang Dandan , Fernández Israel , Berger Robert , Zhou Mingfei , Frenking Gernot 
Published: February 2018

AbstractBa(CO)+ and Ba(CO)− have been produced and isolated in a low‐temperature neon matrix. The observed C−O stretching wavenumber for Ba(CO)+ of 1911.2 cm−1 is the most red‐shifted value measured for any metal carbonyl cations, indicating strong π backdonation of electron density from Ba+ to CO. Quantum chemical calculations indicate that Ba(CO)+ has a 2Π reference state, which correlates with the 2D(5d1) excited state of Ba+ that comprises significant Ba+(5dπ1)→CO(π* LUMO) backbonding, letting the Ba(CO)+ complex behave like a conventional transition‐metal carbonyl. A bonding analysis shows that the π backdonation in Ba(CO)+ is much stronger than the Ba+(5dσ/6s)←CO(HOMO) σ donation. The Ba+ cation in the 2D(5d1) excited state is a donor rather than an acceptor. Covalent bonding in the radical anion Ba(CO)− takes place mainly through Ba(5dπ)←CO−(π* SOMO) π donation and Ba(5dσ/6s)←CO−(HOMO) σ donation. The most important valence functions at barium in Ba(CO)+ cation and Ba(CO)− anion are the 5d orbitals.
Highly Stable Aqueous Zinc‐Ion Storage Using a Layered Calcium Vanadium Oxide Bronze Cathode
Authors: Xia Chuan , Guo Jing , Li Peng , Zhang Xixiang , Alshareef Husam N. 
Published: February 2018

AbstractCost‐effective aqueous rechargeable batteries are attractive alternatives to non‐aqueous cells for stationary grid energy storage. Among different aqueous cells, zinc‐ion batteries (ZIBs), based on Zn2+ intercalation chemistry, stand out as they can employ high‐capacity Zn metal as the anode material. Herein, we report a layered calcium vanadium oxide bronze as the cathode material for aqueous Zn batteries. For the storage of the Zn2+ ions in the aqueous electrolyte, we demonstrate that the calcium‐based bronze structure can deliver a high capacity of 340 mA h g−1 at 0.2 C, good rate capability, and very long cycling life (96 % retention after 3000 cycles at 80 C). Further, we investigate the Zn2+ storage mechanism, and the corresponding electrochemical kinetics in this bronze cathode. Finally, we show that our Zn cell delivers an energy density of 267 W h kg−1 at a power density of 53.4 W kg−1.
Synthesis of Alternating Donor–Acceptor Ladder‐Type Molecules and Investigation of Their Multiple Charge‐Transfer Pathways
Authors: Cai Zhengxu , Zhang Na , Awais Mohammad A. , Filatov Alexander S. , Yu Luping 
Published: February 2018

AbstractWe describe the synthesis as well as the optical and charge‐transport properties of a series of donor–acceptor (D‐A) ladder‐type heteroacenes. These molecules are stable, soluble, and contain up to 24 fused rings. Structural analyses indicated that the backbones of S 10r and Se 10r are bent in single crystals. The three 10‐ring heteroacenes were functionalized with thiol anchoring groups and used for single‐molecular conductance measurements. The highest conductance was observed for molecular wires containing a benzoselenadiazole (BSD) moiety, which exhibits the narrowest band gap. Multiple charge‐transport pathways were observed in molecular wires containing either benzothiadiazole (BTD) or BSD. The conductance is a complex function of both energy gap and orbital alignment.
A Smart Superwetting Surface with Responsivity in Both Surface Chemistry and Microstructure
Authors: Zhang Dongjie , Cheng Zhongjun , Kang Hongjun , Yu Jianxin , Liu Yuyan , Jiang Lei 
Published: February 2018

AbstractRecently, smart surfaces with switchable wettability have aroused much attention. However, only single surface chemistry or the microstructure can be changed on these surfaces, which significantly limits their wetting performances, controllability, and applications. A new surface with both tunable surface microstructure and chemistry was prepared by grafting poly(N‐isopropylacrylamide) onto the pillar‐structured shape memory polymer on which multiple wetting states from superhydrophilicity to superhydrophobicity can be reversibly and precisely controlled by synergistically regulating the surface microstructure and chemistry. Meanwhile, based on the excellent controllability, we also showed the application of the surface as a rewritable platform, and various gradient wettings can be obtained. This work presents for the first time a surface with controllability in both surface chemistry and microstructure, which starts some new ideas for the design of novel superwetting materials.
Ion‐Selective Electrodes Based on Hydrophilic Ionophore‐Modified Nanopores
Authors: Papp Soma , Jágerszki Gyula , Gyurcsányi Róbert E. 
Published: February 2018

AbstractWe report the synthesis and analytical application of the first Cu2+‐selective synthetic ion channel based on peptide‐modified gold nanopores. A Cu2+‐binding peptide motif (Gly‐Gly‐His) along with two additional functional thiol derivatives inferring cation‐permselectivity and hydrophobicity was self‐assembled on the surface of gold nanoporous membranes comprising of about 5 nm diameter pores. These membranes were used to construct ion‐selective electrodes (ISEs) with extraordinary Cu2+ selectivities, approaching six orders of magnitude over certain ions. Since all constituents are immobilized to a supporting nanoporous membrane, their leaching, that is a ubiquitous problem of conventional ionophore‐based ISEs was effectively suppressed.
Formation of a Highly Reactive Cobalt Nanocluster Crystal within a Highly Negatively Charged Porous Coordination Cage
Authors: Fang Yu , Xiao Zhifeng , Li Jialuo , Lollar Christina , Liu Lujia , Lian Xizhen , Yuan Shuai , Banerjee Sayan , Zhang Peng , Zhou Hong‐Cai 
Published: February 2018

AbstractEarth‐abundant first‐row transition‐metal nanoclusters (NCs) have been extensively investigated as catalysts. However, their catalytic activity is relatively low compared with noble metal NCs. Enhanced catalytic activity of cobalt NCs can be achieved by encapsulating Co NCs in soluble porous coordination cages (PCCs). Two cages, PCC‐2a and 2b, possess almost identical cavity in shape and size, while PCC‐2a has five times more net charges than PCC‐2b. Co2+ cations were accumulated in PCC‐2a and reduced to ultra‐small Co NCs in situ, while for PCC‐2b, only bulky Co particles were formed. As a result, Co NCs@PCC‐2a accomplished the highest catalytic activity in the hydrolysis of ammonium borane among all the first‐row transition‐metals NCs. Based on these results, it is envisioned that confining in the charged porous coordination cage could be a novel route for the synthesis of ultra‐small NCs with extraordinary properties.
Counterion‐Induced Asymmetric Control in Ring‐Opening of Azetidiniums: Facile Access to Chiral Amines
Authors: Qian Deyun , Chen Min , Bissember Alex C. , Sun Jianwei 
Published: February 2018

AbstractCounterion‐induced stereocontrol is a powerful tool in organic synthesis. However, such enantiocontrol on tetrahedral ammonium cations remains challenging. Described here is the first example of using chiral anion phase‐transfer catalysis to achieve intermolecular ring‐opening of azetidiniums with excellent enantioselectivity (up to 97 % ee). Precise control over the formation and reaction of the chiral ion pair as well as inhibition of the background reaction by the biphasic system is key to the success of the reaction.
Reversible Phase Transfer of Carbon Dots between an Organic Phase and Aqueous Solution Triggered by CO2
Authors: Pei Xiaoyan , Xiong Dazhen , Wang Huiyong , Gao Shuaiqi , Zhang Xinying , Zhang Suojiang , Wang Jianji 
Published: February 2018

AbstractCarbon dots (CDs) have attracted increasing attention in applications such as bio‐imaging, sensors, catalysis, and drug delivery. However, unlike metallic and semiconductor nanoparticles, the transfer of CDs between polar and non‐polar phases is little understood. A class of amine‐terminated CDs is developed and their phase transfer behavior has been investigated. It is found that these CDs can reversibly transfer between aqueous and organic solvents by alternatively bubbling and removing CO2 at atmospheric pressure. The mechanism of such CO2‐switched phase transfer involves reversible acid–base reaction of amine‐terminated CDs with CO2 and the reversible formation of hydrophilic ammonium salts. By using the CDs as catalysts, the phase transfer is applied in the Knoevenagel reaction for efficient homogeneous reaction, heterogeneous separation, and recycling of the catalysts.
Blending Non‐Group‐3 Transition Metal and Rare‐Earth Metal into a C80 Fullerene Cage with D5h Symmetry
Authors: Wei Tao , Jin Fei , Guan Runnan , Huang Jing , Chen Muqing , Li Qunxiang , Yang Shangfeng 
Published: February 2018

AbstractRare‐earth metals have been mostly entrapped into fullerene cages to form endohedral clusterfullerenes, whereas non‐Group‐3 transition metals that can form clusterfullerenes are limited to titanium (Ti) and vanadium (V), and both are exclusively entrapped within an Ih‐C80 cage. Non‐Group‐3 transition‐metal‐containing endohedral fullerenes based on a C80 cage with D5h symmetry, VxSc3−xN@D5h‐C80 (x=1, 2), have now been synthesized, which exhibit two variable cluster compositions. The molecular structure of VSc2N@D5h‐C80 was unambiguously determined by X‐ray crystallography. According to a comparative study with the reported Ti‐ and V‐containing clusterfullerenes based on a Ih‐C80 cage and the analogous D5h‐C80‐based metal nitride clusterfullerenes containing rare‐earth metals only, the decisive role of the non‐Group‐3 transition metal on the formation of the corresponding D5h‐C80‐based clusterfullerenes is unraveled.
Effective gas separation through graphene oxide containing mixed matrix membranes
Authors: Feijani Elahe Ahmadi , Tavassoli Ahmad , Mahdavi Hossein , Molavi Hossein 
Published: February 2018

ABSTRACTIn the present study, graphene oxide (GO) was incorporated into poly(vinylidene fluoride) (PVDF) and chemically modified PVDF (M‐PVDF) to prepare mixed matrix membranes (MMMs) for gas separation application. Performed analyses proved appropriate dispersion of exfoliated GO sheets in polymer matrices and sufficient compatibility at the interfacial phases. M‐PVDF based MMMs were thermally and mechanically more stable relative to the PVDF‐based MMMs. The oxygen containing functional groups in M‐PVDF was probably the main reason for this more stability. PVDF/GO MMMs rendered low gas permeability and high selectivity. Both impermeable GO sheets and crystalline phases of PVDF were responsible for such behavior. On the other hand, interestingly gas permeability of M‐PVDF/GO MMMs was enhanced while no substantial decline was recorded in gas selectivity. For instance, He and CO2 permeability was increased 12.46% and 25.89%, respectively, compared to the pure PVDF membrane. This behavior originated from functional groups of M‐PVDF and the interaction of these groups with GO sheets. Since GO often amplified gas barrier properties of polymers, such increscent would be appreciable. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46271.
Regulating the arm structure of star‐shaped polycarboxylate superplasticizers as a means to enhance cement paste workability
Authors: Zhao Yangyang , Nian Fuwei , Pang Hao , Huang Jianheng , Zhao Hongwei , Wang Kun , Liao Bing 
Published: February 2018

ABSTRACTStar‐shaped superplasticizers, which incorporated polyol ester with unsaturated bond at their cores and bore comb‐type structures as their arms were synthesized via esterification‐copolymerization in aqueous phase from pentaerythritol, acrylic acid (AA), and isopentenyl oxy poly(ethylene glycol ether) (TPEG). The monomer ratios of AA and TPEG were varied and comonomer sodium methallyl sulfonate (SMAS) bearing short side chains was added to regulate the arm structure of star‐shaped polycarboxylate superplasticizers (SPCEs). The effects of the SPCEs on cement paste were investigated and the cement dispersion as well as early hydration mechanism were explored. As a main result, SPCEs with SMAS and certain molar ratios for anchoring groups and PEO side‐chains in their arm structure exhibited good paste dispersion and fluidity retention, which also delayed the early hydration process and prolonged both the initial and the final setting time. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46312.
Messunsicherheit und ihr Einfluss auf „wesentliche Merkmale“ von mechanischen Befestigungen
Authors: Zeman Oliver , Schwenn Michael , Bergmeister Konrad 
Published: February 2018

AbstractLaboratorien, die Prüfungen oder Kalibrierungen durchführen, müssen nach ISO 17025 in der Lage sein, die Messunsicherheit bei Durchführung der Prüfungen zu bestimmen. Dies kann durch exakte rechnerische Ermittlung als auch durch geeignete Schätzung erfolgen. Alle Beiträge, welche für die Ermittlung der Messunsicherheit von Bedeutung sind, müssen nach sinnvollem Ermessen dazu herangezogen werden. Im spezifischen Fall der Prüfung von nachträglichen Befestigungen in Beton nach European Assessment Document EAD 330232 bzw. EOTA Technical Report 048 wird ebenfalls die Einhaltung der Anforderungen der ISO 17025 hinsichtlich messtechnischer Rückführung und der Bestimmung der Messunsicherheit gefordert.In diesem Beitrag wird aus der Sicht von Prüfstellen im Bereich der Befestigungstechnik untersucht, inwiefern die Messunsicherheit auf Grundlage der normativ bzw. in Regelwerken vorgegebenen Genauigkeitsanforderungen an die Prüfeinrichtungen einen Einfluss auf die wesentlichen Merkmale („essential characteristics“) hat. Es wird gezielt auf die Bestimmung der Beiträge zum Messunsicherheitsbudget bei der Bestimmung einer zentrischen Auszugslast Fu eingegangen, wobei für den Anwender die theoretische mathematische Herleitung der Empfindlichkeitsfaktoren c gezeigt wird.Für einen vereinfachten Ansatz wird eine Hilfestellung zur Abschätzung des Einflusses des Betonuntergrunds und der Verankerungstiefe auf die Messunsicherheit bei Ermittlung der Auszugslasten gegeben.
Metabolite identification of the antimalarial naphthoquine using liquid chromatography–tandem high‐resolution mass spectrometry in combination with multiple data‐mining tools
Authors: Sun Yanhong , Wang Shuqi , Ji Jianbo , Zhai Guangxi , Xing Jie 
Published: February 2018

AbstractNaphthoquine (NQ) is one of important partner drugs of artemisinin‐based combination therapy (ACT), which is recommended for the treatment of uncomplicated Plasmodium falciparum. NQ shows a high cure rate after a single oral administration. It is absorbed quickly (time to peak concentration 2–4 h) and has a long elimination half‐life (255 h). However, the metabolism of NQ has not been clarified. In this work, the metabolite profiling of NQ was studied in six liver microsomal incubates (human, cynomolgus monkey, beagle dog, mini pig, rat and CD1 mouse), seven recombinant CYP enzymes (1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A4) and rat (plasma, urine, bile and feces) using liquid chromatography tandem high‐resolution LTQ‐Orbitrap mass spectrometry (HRMSn) in conjunction with online hydrogen/deuterium exchange. The biological samples were pretreated by protein precipitation and solid‐phase extraction. For data processing, multiple data‐mining tools were applied in tandem, i.e. background subtraction and followed by mass defect filter. NQ metabolites were characterized by accurate MS/MS fragmentation characteristics, the hydrogen/deuterium exchange data and cLogP simulation. As a result, five phase I metabolites (M1–M5) of NQ were characterized for the first time. Two metabolic pathways were involved: hydroxylation and N‐oxidation. This study demonstrates that LC‐HRMSn in combination with multiple data‐mining tools in tandem can be a valuable analytical strategy for rapid metabolite profiling of drugs.
In vivo microdialysis with ultra performance liquid chromatography–mass spectrometry for analysis of tetramethylpyrazine and its interaction with borneol in rat brain and blood
Authors: Liao Weiguo , Huang Xiaojie , Yin Yongxin , Liu Bin , Zhu Runzhi 
Published: February 2018

AbstractTetramethylpyrazine (TMP) has been widely used in the treatment of ischemic cerebrovascular disease. However, the mechanism of TMP and how to increase its bioavailability need to be further explored. In our study, an in vivo microdialysis sampling technique coupled with ultra‐performance liquid chromatography–mass spectrometry method was developed to investigate the pharmacokinetic properties of TMP and its interaction with different doses of borneol (BO) in rats. Linearity of TMP in brain and blood dialysates exhibited good linear relationships over the concentration range of 0.991–555.14 ng/mL. The specificity, linearity, accuracy, precision, matrix effect and stability were within acceptable ranges. The results demonstrated that BO had a marked impact on the pharmacokinetic properties of TMP. After co‐administration, the areas under the concentration–time curve (AUC) of TMP in brain and blood were significantly increased. Meanwhile, the peak concentration of TMP in brain was also enhanced. The AUCBrain/AUCBlood of TMP, increased from 44% to 56 and 60.8% after co‐administration with BO (15 and 30 mg/kg). The pharmacodynamic results showed that TMP co‐administration with BO enhanced the cerebral blood flow during the period of ischemia and reduced the infarct volume. Overall, it might be an effective way to treat stroke to use TMP co‐administered with BO.