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The Co-7(AlePy)(2) polyoxometalate, which encloses a {(PW9)(2)Co-7(II)} core covalently bound to two free aminopyridine groups through bisphosphonate ligands (AlePy), has been isolated. It can be used as a precursor, allowing the synthesis of heterometallic hybrid compounds, as illustrated by the characterization of cobalt/zinc (Co-7(AlePyZn)(2)), cobalt/palladium (Co-7(AlePyPd)(2)), and cobalt/platinum (Co-7(AlePyPt)(2)) species. A composite based on the water-insoluble precious metal-free Co-7(AlePyZn)(2) compound and the low-cost carbon material Vulcan XC-72 has been selected as a cathode material (Co7Zn/C) for oxygen reduction reaction studies. The electrocatalytic performances of the Co7Zn/C hybrids were assessed at neutral and basic pH, showing that Co7Zn/C exhibits high selectivity for the four-electron reduction of O-2. Moreover, its durability is superior to that of a commercial Pt/C catalyst with 20% loading. Also, comparative studies performed in the presence of methanol have indicated that Co7Zn/C has a much better tolerance to the crossover effect than Pt/C. Altogether, these results indicate for the first time that, even in neutral media, polyoxometalate/carbon composites can represent low-cost oxygen reduction catalysts that can function stably, for a long time, and with high performance.

The long-carbon-fiber-reinforced polyamide-6/nickel powder composites were designed as electromagnetic interference (EMI) shielding materials and then were prepared through the joint processing of melt blending and thermoplastic pultrusion. The obtained composites show high conductivity and permittivity as well as a high dielectric loss with co-addition of carbon fiber and nickel powders, which makes the resulting composites a higher level of shielding effectiveness due to the combination of conductive and magnetic fillers. The composites are capable of shielding mainly through absorption rather than reflection. On the other hand, the composites achieved significant improvements in tensile, flexural, and impact strength due to the superiority of the long-carbon-fiber-reinforced technique. The residual fiber length in the injectionmolded specimens is greatly superior to the critical one predicted by the Kelly–Tyson model. This takes full advantage of the strength of the reinforcing fiber itself, thus leading to a promising reinforcement effect. The enhancement of impact toughness is due to the energy dissipation by fiber fracture as a result of long fiber effect. The morphologic investigation indicated that the fiber fracture and fiber pullout concurred on the impact and tensile fracture surfaces, and the former preceded the latter. Highlighted with both good EMI shielding properties and excellent mechanical performance, the composites designed by this work exhibit potential applications for the automotive, electronic, aerospace, and military industries. POLYM. COMPOS., 00:000–000, 2015. V C 2015 Society of Plastics Engineers

Gelsemine from Gelsemium elegans Benth is a potential anesthetic and analgesic agent with no physical dependence and opiate addiction. This study was aimed at developing an ultrafast liquid chromatography coupled to tandem mass spectrometry method to quantify gelsemine in rat plasma and tissues. Plasma and tissues were processed with acetonitrile precipitation, and dendrobine was chosen as the internal standard. Sample separation was performed on an ACQUITY HSS T3 column. The mobile phase consisted of acetonitrile and 0.1% formic acid aqueous solution. Multiple reactions monitoring mode was utilized to detect the compounds of interest. The mass spectrometer was operated in the positive ion mode for detection. The MS/MS ion transitions monitored were m/z 323.2→70.5 for gelsemine and 264.2→108.05 for dendrobine, respectively. The calibration curves were linear over the range of 1-500 ng/mL in all biological matrices. The lower limit of quantification for rats plasma and tissues was 1.0 ng/mL. The values for inter- and intraday precision and accuracy were well within the ranges acceptable (< 15%). It was successfully applied to the pharmacokinetic and tissue distribution studies of gelsemine after intravenous doses of 5, 2, and 0.5 mg/kg in rats. These data of gelsemine would be useful for clinical application and further development.

Background Pregabalin is considered to be an effective treatment for painful diabetic peripheral neuropathy (DPN), but controversy exists about its efficacy and safety. We performed a meta-analysis to systematically assess the efficacy and safety of pregabalin for managing pain associated with DPN. Methods Medline, EMBASE, and the Cochrane Central Register were searched in July 2014 for randomized, double-blind, placebo-controlled trials published in English on the use of pregabalin to treat DPN-associated pain. Principal outcomes were mean pain score after pregabalin treatment and the proportions of patients showing a pain reduction of at least 50%. Results Nine trials involving a total of 2056 participants were identified. Pooled analysis showed that pregabalin was significantly superior to placebo for improving mean pain scores [mean difference (MD) = −0.79, P

Phase behaviors induced by solvent annealing in poly(methyl methacrylate) (PMMA) and poly(styrene-ran-acrylonitrile) (SAN) blend ultrathin films have been investigated by atomic force microscopy and grazing incidence small-angle X-ray scattering. Our results indicate that both the phase separation within the blend and the dewetting of the film induced by composition fluctuation take place upon the selective solvent annealing, producing complex structures containing upper droplets (of one phase) and mimic-films (of the other rich-phase). The use of acetic acid (the selective solvent for PMMA) generates PMMA mimic-film and SAN droplets, while the introduction of DMF (exhibiting better solubility for SAN) vapor results in the formation of SAN mimic-film and PMMA droplets. Essentially, the interaction at polymer/substrate interface, resultant wettability of selected component, solubility of PMMA and SAN in adopted solvent dominate not only the phase separation and the dewetting of the whole film but also the synergism of them. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1243–1251

A new hydrogen peroxide detection sensitive material, boron doped carbonized ZIF-67@graphene (Co-N/C@G-B) is synthesized through pyrolysis of a sandwich-like ZIF-67 coating graphene material. After doping boron atoms by using chemical vapor deposition method, new active sites such as Co2B and B-N-C bonds are created, and mesopores are significantly increased. Most importantly, this Co-N/C@G-B material is found to exhibit excellent performance as an enzyme-free biosensor for detecting hydrogen peroxide with a very wide detection range (from 0.5 x 10(-6) to 60 x 10(-3) M), a low detection limit (0.19 x 10(-6)M), and a rapid response time (approximate to 3 s). The prepared biosensor also shows strong anti-interference ability in the complex working occasions. Furthermore, for real application of the materials, an electronic device of biosensor is developed by using technologies of screen printing electrode, integrated circuit, 3D printed shell, and custom-developed program, which shows high sensitivity and portability to detect hydrogen peroxide. Such device paves a way for further practical application of advanced materials in commercial scale.