bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computational Studies of Electrode Materials in Sodium‐Ion Batteries
Authors: Bai Qiang , Yang Lufeng , Chen Hailong , Mo Yifei 
Published: March 2018

AbstractSodium‐ion batteries have attracted extensive interest as a promising solution for large‐scale electrochemical energy storage, owing to their low cost, materials abundance, good reversibility, and decent energy density. For sodium‐ion batteries to achieve comparable performance to current lithium‐ion batteries, significant improvements are still required in cathode, anode, and electrolyte materials. Understanding the functioning and degradation mechanisms of the materials is essential. Computational techniques have been widely applied in tandem with experimental investigations to provide crucial fundamental insights into electrode materials and to facilitate the development of materials for sodium‐ion batteries. Herein, the authors review computational studies on electrode materials in sodium‐ion batteries. The authors summarize the current state‐of‐the‐art computational techniques and their applications in investigating the structure, ordering, diffusion, and phase transformation in cathode and anode materials for sodium‐ion batteries. The unique capability and the obtained knowledge of computational studies as well as the perspectives for sodium‐ion battery materials are discussed in this review.
Experimental Studies on Work Functions of Li+ Ions and Electrons in the Battery Electrode Material LiCoO2: A Thermodynamic Cycle Combining Ionic and Electronic Structure
Authors: Schuld Stephan , Hausbrand René , Fingerle Mathias , Jaegermann Wolfram , Weitzel Karl‐Michael 
Published: March 2018

AbstractThe release of Li+ from stoichiometric LiCoO2 (LCO) – a typical battery electrode material – is investigated by means of thermionic emission. Analysis of the data leads to an ionic work function of wLi+(LCO) = 4.1 eV. Combination of this value with the electronic work function we− (LCO) = 5.1 eV, also measured in this work by photoelectron spectroscopy, and with information available from the literature allows the set up, for the first time, of a complete thermodynamic cycle for a Li//LiCoO2 battery. An open circuit cell voltage of 2.4 eV is derived in line with available literature information. The proof‐of‐principle study presented here provides experimental data on the binding energy values, i.e., chemical potentials, of Li+‐ions and electrons and thus of Li‐atoms in LiCoO2 as a battery cathode and is expected to open access to a better understanding and thus to a better design of battery materials.
In Situ Exfoliating and Generating Active Sites on Graphene Nanosheets Strongly Coupled with Carbon Fiber toward Self‐Standing Bifunctional Cathode for Rechargeable Zn–Air Batteries
Authors: Hang Chao , Zhang Jian , Zhu Jiawei , Li Wenqiang , Kou Zongkui , Huang Yunhui 
Published: March 2018

AbstractThe self‐standing electrode nanomaterials with highly effective bifunctional electrocatalysis for oxygen reduction and evolution reactions (ORR/OER) are important for practical applications in metal–air batteries. Herein, a defect‐enriched and pyridinic‐N (PN) dominated bifunctional electrocatalyst with novel core–shell architecture (DN‐CP@G) is successfully fabricated by in situ exfoliating graphene from carbon paper followed by high temperature ammonia treatment. Benefitting from its strongly coupled core–shell structure, abundant defective sites and high‐content PN dopants, the DN‐CP@G displays an excellent electrocatalytic (ORR and OER) activity and stability in alkaline media, which are comparable to commercial Pt/C and Ir/C catalysts. The experiment, and theoretical calculations demonstrate that the electrocatalytic activities of carbon materials strongly depend on their defective sites and PN dopants. By directly using DN‐CP@G as a self‐standing electrode, the assembled zinc–air battery demonstrates a high discharge performance and outstanding long‐term cycle stability with at least 250 cycles, which is much superior to the mixed Pt/C and Ir/C electrodes. Remarkably, the DN‐CP@G based all‐solid‐state battery also reveals a good discharge and cycle performance. A facile and cost‐efficient approach to prepare highly effective bifunctional self‐standing electrode is provided by in situ generation of active sites on carbon support for metal–air batteries.
Thermally Stable All‐Polymer Solar Cells with High Tolerance on Blend Ratios
Authors: Zhang Yannan , Xu Yalong , Ford Michael J. , Li Fangchao , Sun Jianxia , Ling Xufeng , Wang Yongjie , Gu Jinan , Yuan Jianyu , Ma Wanli 
Published: March 2018

AbstractTuning the blend composition is an essential step to optimize the power conversion efficiency (PCE) of organic bulk heterojunction (BHJ) solar cells. PCEs from devices of unoptimized donor:acceptor (D:A) weight ratio are generally significantly lower than optimized devices. Here, two high‐performance organic nonfullerene BHJ blends PBDB‐T:ITIC and PBDB‐T:N2200 are adopted to investigate the effect of blend ratio on device performance. It is found that the PCEs of polymer‐polymer (PBDB‐T:N2200) blend are more tolerant to composition changes, relative to polymer‐molecule (PBDB‐T:ITIC) devices. In both systems, short‐circuit current density (Jsc) is tracked closely with PCE, indicating that exciton dissociation and transport strongly influence PCEs. With dilute acceptor concentrations, polymer‐polymer blends maintain high electron mobility relative to the polymer‐molecule blends, which explains the dramatic difference in PCEs between them as a function of D:A blend ratio. In addition, polymer‐polymer solar cells, especially at high D:A blend ratio, are stable (less than 5% relative loss) over 70 d under continuous heating at 80 °C in a glovebox without encapsulation. This work demonstrates that all‐polymer solar cells show advantage in operational lifetime under thermal stress and blend‐ratio resilience, which indicates their high potential for designing of stable and scalable solar cells.
Sulfur/Oxygen Codoped Porous Hard Carbon Microspheres for High‐Performance Potassium‐Ion Batteries
Authors: Chen Mei , Wang Wei , Liang Xiao , Gong Sheng , Liu Jie , Wang Qian , Guo Shaojun , Yang Huai 
Published: March 2018

AbstractPotassium‐ion batteries (KIBs) are very promising alternatives to lithium‐ion batteries (LIBs) for large‐scale energy storage. However, traditional carbon anode materials usually show poor performance in KIBs due to the large size of K ions. Herein, a carbonization‐etching strategy is reported for making a class of sulfur (S) and oxygen (O) codoped porous hard carbon microspheres (PCMs) material as a novel anode for KIBs through pyrolysis of the polymer microspheres (PMs) composed of a liquid crystal/epoxy monomer/thiol hardener system. The as‐made PCMs possess a porous architecture with a large Brunauer–Emmett–Teller surface area (983.2 m2 g−1), an enlarged interlayer distance (0.393 nm), structural defects induced by the S/O codoping and also amorphous carbon nature. These new features are important for boosting potassium ion storage, allowing the PCMs to deliver a high potassiation capacity of 226.6 mA h g−1 at 50 mA g−1 over 100 cycles and be displaying high stability by showing a potassiation capacity of 108.4 mA h g−1 over 2000 cycles at 1000 mA g−1. The density functional theory calculations demonstrate that S/O codoping not only favors the adsorption of K to the PCMs electrode but also reduces its structural deformation during the potassiation/depotassiation. The present work highlights the important role of hierarchical porosity and S/O codoping in potassium storage.
Stereoselective Construction of Cisoidal Bisspiroacetal Frameworks through Magnesium Coordination of the Bilateral Acetal Oxygen Atoms
Authors: Yasukawa Yoshifumi , Tsuchikawa Hiroshi , Todokoro Yasuto , Murata Michio 
Published: March 2018

AbstractThe cisoid‐selective construction of a tricyclic bisspiroacetal framework was demonstrated using MgBr2 as a cisoid stabilizer through chelation of the oxygen atoms of lateral acetal rings in the cisoid configuration. The method was also successfully applied to substrates with different ring sizes and substituents. Thus, this method serves as a useful synthetic strategy for the total synthesis of bisspiroacetal‐containing natural products.
Avoiding Thiol Compound Interference: A Nanoplatform Based on High‐Fidelity Au–Se Bonds for Biological Applications
Authors: Hu Bo , Kong Fanpeng , Gao Xiaonan , Jiang Lulu , Li Xiaofeng , Gao Wen , Xu Kehua , Tang Bo 
Published: March 2018

AbstractGold nanoparticles (Au NPs) assembled through Au−S covalent bonds have been widely used in biomolecule‐sensing technologies. However, during the process, detection distortions caused by high levels of thiol compounds can still significantly influence the result and this problem has not really been solved. Based on the higher stability of Au−Se bonds compared to Au−S bonds, we prepared selenol‐modified Au NPs as an Au‐Se nanoplatform (NPF). Compared with the Au‐S NPF, the Au‐Se NPF exhibits excellent anti‐interference properties in the presence of millimolar levels of glutathione (GSH). Such an Au‐Se NPF that can effectively avoid detection distortions caused by high levels of thiols thus offers a new perspective in future nanomaterial design, as well as a novel platform with higher stability and selectivity for the in vivo application of chemical sensing and clinical therapies.
A Monoaryllead Trichloride That Resists Reductive Elimination
Authors: Olaru Marian , Kather Ralf , Hupf Emanuel , Lork Enno , Mebs Stefan , Beckmann Jens 
Published: March 2018

AbstractTransmetallation of Pb(OAc)4with R2Hg (1), followed by treatment with HCl in Et2O, provided RPbCl3(2), the first kinetically stabilized monoorganolead trihalide that resists reductive elimination under ambient conditions. The kinetic stabilisation relies on an intramolecularly coordinating O‐donor substituent (R=6‐Ph2P(O)‐Ace‐5‐). The gram‐scale preparation of2was key for the synthesis of unsymmetrically substituted diaryllead dichlorides RR′PbCl2(3 a, R′=Ph;3 b, R′=4‐MeOC6H4;3 c, R′=4‐Me2NC6H4).
Structure and properties of porous poly(vinyl alcohol) hydrogel beads prepared through a physical–chemical crosslinking method
Authors: Liao Honghui , Liu Yuan , Wang Qi , Duan Wenfeng 
Published: March 2018

ABSTRACTPorous poly(vinyl alcohol) (PVA) hydrogel beads (PC beads) are potential microorganism carriers applied in wastewater treatment industries. However, improving the mechanical strength and stability of traditional PVA hydrogel beads in water is still a challenge. In this research, a new kind of PC bead was successfully prepared by a combination of physical and chemical crosslinking methods. The structures and properties of the PC beads and conventional PVA beads obtained by individual chemical (boric acid) or physical (cyclic freezing and thawing) processes were investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, and tensile and hydraulic stability testing. Compared with the conventional products, the PC beads displayed a more homogeneous and porous structure, bigger surface area, higher hydraulic stability, and better mechanical properties and showed better applicability for the water treatment field. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46402.
Morphology, drug release behavior, thermal, and mechanical properties of poly(ethylene oxide) (PEO)/poly(vinyl pyrrolidone) (PVP) blends
Authors: Naghdi Sedeh Negar , Entezam Mehdi , Hassan Jafari Seyed , Khonakdar Hossein‐Ali , Abdouss Majid 
Published: March 2018

ABSTRACTPoly(ethylene oxide) (PEO)/poly(vinyl pyrrolidone) (PVP) blends containing different amounts of PVP (0, 10, 25, 50, and 100 wt %) prepared by a solution casting method were characterized in terms of microstructure, thermal, and mechanical properties along with their drug release behavior. Fourier‐transform infrared spectroscopy results confirmed formation of hydrogen bonds between PEO and PVP. Although scanning electron microscopy micrographs showed no phase separation in the blends, the elemental analysis data obtained by energy dispersive X‐ray technique revealed partial miscibility between the blend components. The miscibility of the blend and degree of crystallinity of PEO component of the blend were decreased with increasing PVP content of the blend. The nucleating role of PVP in crystallization of PEO was confirmed by differential scanning calorimetry analysis. A synergistic effect on mechanical properties was obtained as a result of blending PVP with PEO. The results of curcumin release studies from the films indicated that, the blends have lower diffusion coefficients and slower drug release rate as compared to the neat PEO. Theoretical analysis of the drug release data using Peppas's model revealed that the kinetic of drug release from all the films is governed by a non‐Fickian diffusion mechanism. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46403.
Suspension polymerization of itaconic acid diesters
Authors: Chakraborty Sanjiban , Ju Lin , Galuska Alan A. , Moore Robert B. , Turner S. Richard 
Published: March 2018

ABSTRACTDimethyl itaconate and dicyclohexyl itaconate monomers are polymerized successfully for the first time via suspension polymerization. The obtained polymers possess significantly higher molecular weights and more narrow polydispersities compared to itaconate polymers prepared in solution or in bulk. The yields of these polymers from the suspension process are higher than the polymers synthesized from bulk. Solution cast films of both polymers were too brittle for mechanical properties characterization. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46417.
Design and study of the potential of crosslinked cationic polymers as drug delivery systems for dermal application
Authors: Kostova Bistra , Georgieva Dilyana , Dundarova Maria , Ivanova Sijka , Ivanova‐Mileva Krasimira , Tzankova Virginia , Christova Darinka 
Published: March 2018

ABSTRACTCrosslinked carriers based on cationic monomer [2‐(acryloyloxy)ethyl]trimethylammonium chloride or 2‐(dimethylamino)ethyl methacrylate were developed and investigated as new platform for ibuprofen transdermal delivery. Series of networks of varied composition and structure were synthesized and characterized by FTIR spectroscopy and following swelling kinetics in different solvents. Dermal safety tests to examine the skin irritation and sensitization potential of the network films were performed in vivo. Chosen network compositions were loaded with ibuprofen by swelling in its ethanol solution. The structures of the drug carriers were investigated by scanning electron microscopy. Ibuprofen release from the developed drug delivery systems was followed in phosphate buffer solution at 37 °C. The investigation proved the feasibility of the developed cationic copolymer networks as effective platforms with modified ibuprofen release for potential dermal application. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46420.
High oxygen barrier multilayer EVOH/LDPE film/foam
Authors: Feng Jingxing , Li Zhenpeng , Olah Andrew , Baer Eric 
Published: March 2018

ABSTRACTHigh oxygen barrier film/foam system had been developed using multilayer coextrusion technology. The film/foams contained alternating ethylene–vinyl alcohol (EVOH) copolymer film layers and low‐density polyethylene (LDPE) foam layers. To ensure good adhesion and layer integrity, the LDPE was preblended with LDPE grafted maleic anhydride. The layered structure of film/foam was characterized by scanning electron microscopy. The film/foams showed adjustable density, oxygen permeability, and mechanical properties by changing the film and foam composition. Film/foam with 10% EVOH film layer was successfully thermoformed at room temperature. The cells in the foam layer were observed to deform during the mechanical forming process. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46425.
N‐methylation in amino acids and peptides: Scope and limitations
Authors: Sharma Anamika , Kumar Ashish , Abdel Monaim Shimaa A. H. , Jad Yahya E. , El‐Faham Ayman , de la Torre Beatriz G. , Albericio Fernando 
Published: March 2018

AbstractActive pharmaceutical ingredients (APIs) can be divided into two types, namely chemical and biological entities. Traditionally, the former has been associated with the so‐called small molecules. The revival of peptides in pharmaceutical industry results from their importance in many biological roles. However, low metabolic stability and the lack of oral availability of most peptides is the main drawback for peptide to fulfill that paradigmatic situation. In this regard, efforts are being channeled into addressing this issue by introducing restrictions into the flexible peptide backbone, mainly through N‐methyl amino acids (NMAAs) or development of small cyclic peptides. In many cases, both the above restrictions are combined with the aim to enhance oral availability. The synthesis of NMAAs is complex and their introduction into the peptide chain brings additional synthetic challenges and also sometimes leads to side‐reactions. Here we discuss the most efficient methods for the synthesis of NMAAs (either in solution or in solid phase) and also their introduction into peptide sequences. Special attention is also given to the detection of side reactions and the most efficient way to prevent them.
Gold nanoparticles crosslinking by peptides and amino acids: A tool for the colorimetric identification of amino acids
Authors: Martínez Álvaro , Scrimin Paolo 
Published: March 2018

AbstractGold nanoparticles are known to aggregate in the presence of proper multifunctional compounds. For those larger than 3 nm, the process can be followed with the naked eye because the surface plasmon absorption band of the particles shifts to longer wavelengths and the solution color changes from red to blue. To exploit this property, we have used amino acids and peptides as crosslinking agents in ethanol at low µM concentrations. In the case of amino acids, we report a straightforward protocol for their colorimetric identification. We also report that the presence of precise secondary structure and conformational constraints in oligopeptides, directly influence their crosslinking ability. A discussion on the nature of the interactions that induce these phenomena is also reported.
A longitudinal study of the individual‐ and group‐level problematic gaming and associations with problem gambling among Swedish adolescents
Authors: Vadlin Sofia , Åslund Cecilia , Nilsson Kent W. 
Published: March 2018

AbstractAimThe aims of this study were to investigate the long‐term stability of problematic gaming among adolescents and whether problematic gaming at wave 1 (W1) was associated with problem gambling at wave 2 (W2), three years later.MethodsData from the SALVe cohort, including adolescents in Västmanland born in 1997 and 1999, were accessed and analyzed in two waves W2, N = 1576; 914 (58%) girls). At W1, the adolescents were 13 and 15 years old, and at W2, they were 16 and 18 years old. Adolescents self‐rated on the Gaming Addiction Identification Test (GAIT), Problem Gambling Severity Index (PGSI), and gambling frequencies. Stability of gaming was determined using Gamma correlation, Spearman's rho, and McNemar. Logistic regression analysis and general linear model (GLM) analysis were performed and adjusted for sex, age, and ethnicity, frequency of gambling activities and gaming time at W1, with PGSI as the dependent variable, and GAIT as the independent variable, to investigate associations between problematic gaming and problem gambling.ResultsProblematic gaming was relative stable over time, γ = 0.739, p ≤ .001, ρ = 0.555, p ≤ .001, and McNemar p ≤ .001. Furthermore, problematic gaming at W1 increased the probability of having problem gambling three years later, logistic regression OR = 1.886 (95% CI 1.125–3.161), p = .016, GLM F = 10.588, η2 = 0.007, p = .001.ConclusionsProblematic gaming seems to be relatively stable over time. Although associations between problematic gaming and later problem gambling were found, the low explained variance indicates that problematic gaming in an unlikely predictor for problem gambling within this sample.
Improving the Postsecondary Educational Attainment of Youth in Foster Care
Authors: Dworsky Amy 
Published: March 2018

AbstractThis chapter examines what we know about the disparity in postsecondary educational attainment between youth in foster care and their non‐foster care peers, the reasons for it, and the policies and programs that have been developed to address that disparity. It also discusses the unique role that community colleges can play in reducing this disparity.
The Fostering Academics Mentoring Excellence Program
Authors: Day Angelique , Riebschleger Joanne , Wen Jiebing 
Published: March 2018

AbstractPrecollege outreach programs improve college access for underrepresented students; however, information on foster youth engagement in precollege programs is virtually nonexistent. This chapter describes the impact of a precollege program on two‐ and four‐year college enrollment and completion rates.
Process‐centric and data‐centric strategies for enhanced production of l‐asparaginase—an anticancer enzyme, using marine‐derived Aspergillus niger
Authors: Vala Anjana K. , Dudhagara Dushyant R. , Dave Bharti P. 
Published: March 2018

AbstractThe objective of the study was to achieve enhanced production of l‐asparaginase (LA), an anticancer enzyme, by a marine‐derived Aspergillus niger isolate. To improve LA production, optimization of pH, incubation time, and inoculum size was performed using process‐centric (response surface methodology [RSM]) and data‐centric (artificial neural network [ANN]) approaches. The optimized conditions led to a 108.62% rise in LA production. Upon comparison of 2 models for enhanced LA production, based on the R2, mean absolute percentage error, root mean square error, and mean absolute deviation values, the ANN model was observed to be superior over the RSM model. To the authors' best knowledge, the present finding is the first ever report revealing detailed analyses for RSM and ANN models for LA production using a marine‐derived fungus.
Dimerization of the Benzyl Radical in a High‐Temperature Pyrolysis Reactor Investigated by IR/UV Ion Dip Spectroscopy
Authors: Hirsch Florian , Constantinidis Philipp , Fischer Ingo , Bakels Sjors , Rijs Anouk M. 
Published: March 2018

AbstractWe investigate the self‐reaction of benzyl, C7H7, in a high‐temperature pyrolysis reactor. The work is motivated by the observation that resonance‐stabilized benzyl radicals can accumulate in reactive environments and contribute to the formation of polycyclic aromatic hydrocarbons (PAHs) and soot. Reaction products are detected by IR/UV ion dip spectroscopy, using infrared radiation from the free electron laser FELIX, and are identified by comparison with computed spectra. Among the reaction products identified by their IR absorption are several PAHs linked to toluene combustion such as bibenzyl, phenanthrene, diphenylmethane, and fluorene. The identification of 9,10‐dihydrophenanthrene provides evidence for a mechanism of phenanthrene formation from bibenzyl that proceeds by initial cyclization rather than an initial hydrogen loss to stilbene.