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One-dimensional materials favoring efficient charge transfer have attracted enormous attentions. Here cobalt nanochains are prepared by a direct-current (DC) arc-discharge method under the gaseous mixture of He and H 2 . The Co nanochains can range up to several micrometers. When H 2 is replaced by CO 2 , the sample shows a phase evolution from Co nanochains to CoO nanocubes. The ratio of CoO/Co can be effortlessly altered by varying the partial pressure of CO 2 in the reaction gas mixture. CoO nanocubes are attained in the pure CO 2 . The prepared samples are explored as catalyst for oxygen evolution reaction (OER). The catalytic activity is highly dependent on the phase proportion of Co and CoO. The sample prepared under CO 2 :He = 1:7 unveils the optimal OER performance with an onset point of 1.50 V versus reversible hydrogen electrode (RHE) and an overpotential of 350 mV at 10 mA cm −2 . The high OER performance can be attributed to synergistic effect and charge transfer process between Co and CoO. Co can inject electrons into CoO, which manipulates the work function of CoO to make it more suitable for oxygen evolution. The good OER performance can also be ascribed to the defective structure of CoO. The CoO/Co composite shows good robustness with less than 8% current loss throughout the long-term test.

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Highly reversible plating/stripping in aqueous electrolytes is one of the critical processes determining the performance of Zn‐ion batteries, but it is severely impeded by the parasitic side reaction and dendrite growth. Herein, a novel electrolyte engineering strategy is first proposed based on the usage of 100 mM xylitol additive, which inhibits hydrogen evolution reaction and accelerates cations migration by expelling active H2O molecules and weakening electrostatic interaction through oriented reconstruction of hydrogen bonds. Concomitantly, xylitol molecules are preferentially adsorbed by Zn surface, which provides a shielding buffer layer to retard the sedimentation and suppress the planar diffusion of Zn2+ ions. Zn2+ transference number and cycling lifespan of Zn∥Zn cells have been significantly elevated, overwhelmingly larger than bare ZnSO4. The cell coupled with a NaV3O8 cathode still behaves much better than the additive‐free device in terms of capacity retention.

The aim of this study was to develop a cheap, pH-sensitive enteric coating of aspirin with biocompatible polymers. A novel approach was used to develop enteric coating from chitosan (CS) and poly(vinyl alcohol) (PVA). Solutions of CS and PVA (5 : 1 mol ratio) were mixed and selectively crosslinked with tetraethoxysilane. IR analysis confirmed the presence of the incorporated components and the existence of siloxane linkages between CS and PVA. The crosslinking percentage and thermal stability increased with increasing amount of crosslinker. The response of the developed coating in different media, such as water, pH (nonbuffer and buffer), and ionic media showed hydrogel properties. All hydrogels showed low swelling in acidic and basic pH media, whereas maximum swelling was exhibited at neutral pH. This pH sensitivity of the hydrogel has been exploited as enteric coating for commercial aspirin tablets. The dissolution test of enteric-coated aspirin tablet in simulated gastric fluid (pH 1.2) showed 7.11% aspirin release over a period of 2 h, whereas a sustained release of remaining aspirin (83.25%) was observed in simulated intestinal fluid (pH 6.8). V C 2011 Wiley Periodicals, Inc. J Appl Polym Sci 124: [4184][4185][4186][4187][4188][4189][4190][4191][4192] 2012

Several supervised approaches have been proposed for causality identification by relying on shallow linguistic features. However, such features do not lead to improved performance. Therefore, novel sources of knowledge are required to achieve progress on this problem. In this paper, we propose a model for the recognition of causality in verb-noun pairs by employing additional types of knowledge along with linguistic features. In particular, we focus on identifying and employing semantic classes of nouns and verbs with high tendency to encode cause or non-cause relations. Our model incorporates the information about these classes to minimize errors in predictions made by a basic supervised classifier relying merely on shallow linguistic features. As compared with this basic classifier our model achieves 14.74% (29.57%) improvement in F-score (accuracy), respectively.

Hybridization of nanostructured cobalt oxides with carbon nanotubes (CNTs) is considered to be an operative approach to harvest high-performance anode material for lithium-ion batteries (LIBs). On the other hand, there are numerous related works, most of which adopted a "post-combination" strategy, which is not only complicated but also ecologically unpromising for using toxic acid for surface modification of CNTs. Herein, we productively fabricate Co@Co 3 O 4 /CNTs nanocomposite with excellent conductivity through arc discharge following low-temperature oxidation in air. As the anode material for LIBs, this nanocomposite shows an exceedingly high reversible capacity of 820 mA h g −1 at a current density of 0.2 A g −1 after 250 cycles, much higher than its theoretical capacity. The rate performance of the material is also outstanding, with a capacity of 760 mA h g −1 after 350 cycles at 1 A g −1 (103% of the initial capacity) and 529 mA h g −1 after 600 cycles at 2 A g −1 . X-ray photoelectron spectroscopy tests are accomplished to disclose the true cause of extra capacity. And for the first time, we propose an "electron-sharing" storage mode, where extra electrons and Li + can separate and be stored at the interface of cobalt metal/Li 2 O. This not only gives a reasonable revelation for this unusual capacity exceeding the theoretical value but also directs the capacitor-like electrochemical behavior extra capacity. KEYWORDS: Co@Co 3 O 4 /CNTs, arc discharge, high conductivity, lithium-ion batteries (LIBs), electron-sharing

Background: A systematic review (SR) is a sound methodology for collecting evidence on a research topic of interest and establishing the context of future research. Unlike ordinary or even expert literature reviews, SRs are systematic thus increasing the confidence in the findings from the previous published literature. SRs can be carried out by both experienced and novice researchers; however, while expert researchers" experiences with conducting SRs are important for improving the SR body of knowledge, we believe that novice researchers" experiences are equally important to establish what distinct problems they face while carrying out SRs. With a prior knowledge of these issues, novice researchers can better plan their SRs and seek guidance from expert researchers. Aim: The aim of this paper is therefore to report on experiences conducting SRs from the perspective of novice researchers. The paper reports first hand experiences of novices conducting SRs and compares them with the experiences of an expert as well as with the experiences reported in the previous literature. Method: An instrument was created and used to gather the experiences conducting SRs from three PhD students and their supervisor. The instrument covered all the SR steps; it was individually filled out by each of the participating subjects and its data was later on aggregated. Results: The results show that the problems faced by novices in terms of time taken to conduct the review; defining the research questions, inclusion/exclusion criteria, data extraction and data synthesis forms are not faced by expert researchers. Moreover, problems faced by novices related to defining quality criteria are different in nature than those faced by expert researchers. Conclusions: It has been observed that while numerous problems are faced by both novices and experts, many others are specific to novices, where several of these can be solved with the help of domain and SR experts.