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Ni‐rich layered cathodes with ultrahigh nickel content (≥90%), for example LiNi0.9Co0.1O2 (NC0.9), are promising for next‐generation high‐energy Li‐ion batteries (LIBs), but face stability issues related to structural degradation and side reactions during the electrochemical process. Here, surface modulation is demonstrated by integrating a Li+‐conductive nanocoating and gradient lattice doping to stabilize the active cathode efficiently for extended cycles. Briefly, a wet‐chemistry process is developed to deposit uniform ZrO(OH)2 nanoshells around Ni0.905Co0.095(OH)2(NC0.9‐OH) hydroxide precursors, followed by high temperature lithiation to create reinforced products featuring Zr doping in the crust lattice decorated with Li2ZrO3 nanoparticles on the surface. It is identified that the Zr4+ infiltration reconstructed the surface lattice into favorable characters such as Li+ deficiency and Ni3+ reduction, which are effective to combat side reactions and suppress phase degradation and crack formation. This surface control is able to achieve an optimized balance between surface stabilization and charge transfer, resulting in an extraordinary capacity retention of 96.6% after 100 cycles at 1 C and an excellent rate capability of 148.8 mA h g−1 at 10 C. This study highlights the critical importance of integrated surface modulation for high stability of cathode materials in next‐generation LIBs. [ABSTRACT FROM AUTHOR]

As a new molecular recognition element, oligonucleotide aptamer not only has higher affinity and specificity to target molecules, but also has the advantages of wide recognition range, in vitro synthesis and chemical stability compared with conventional antibodies. Since a kind of screening method termed systematic evolution of ligands by exponential enrichment (SELEX) was reported, scientists have extensively researched the methodology of how to highly and efficiently screen out aptamers from a library consisting of a large number of random oligonucleotides. Certainly capillary electrophoresis‐based screening methodologies, including nonequilibrium capillary electrophoresis of equilibrium mixtures, equilibrium capillary electrophoresis of equilibrium mixtures, non‐SELEX, ideal‐filter capillary electrophoresis, capillary transient isotachophoresis, etc., are revolutionary. Compared with conventional SELEX, these capillary electrophoresis‐based methodologies show incomparable advantages such as the single‐round screening of aptamers and increased successful screening rate. Methodology studies on the screening process of aptamers are comprehensively reviewed. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study is to develop a new micellar electrokinetic capillary chromatography with field amplified sample stacking for the determination of five kinds of macrolide antibiotic residues in milk. The main factors that affect the separation and enrichment of these analytes were optimized. The optimum running buffer was composed of 60 mM phosphate, 5 mM sodium cholate, and 1.0 mM cetyltrimethyl ammonium bromide at pH 7.0. The separation voltage was 20 kV and the sample was electrokinetically injected at 10 kV for 120 s. The detection wavelength was set at 195 nm. Under the optimized conditions, the enrichment factor of tilmicosin, erythromycin, clarithromycin, roxithromycin, and tylosin were 866, 565, 908, 702, and 675, respectively. The limits of detection ranged from 0.002 to 0.004 mg/kg. The method shall meet the requirement of their maximum residue limits ruled by China, the European Union, the United States, and other countries. Practical applications: The developed method has been applied successfully to the determination of the milk samples spiked at 0.05 and 0.1 mg/kg. The recoveries ranging from 72.8 to 93.7% demonstrate that the method can be applied to the detection of tilmicosin, erythromycin, clarithromycin, roxithromycin, and tylosin residues in milk. [ABSTRACT FROM AUTHOR]

We present a fast time-domain multiphysics simulation framework that combines full-wave electromagnetism (EM) and carrier transport in semiconductor devices (technology computer-aided design (TCAD)) for radio frequency (RF) and mixed-signal modules. The proposed framework features a division of linear and nonlinear components in the EM-TCAD coupled system. The linear portion is extracted and handled independently with high efficiency by a matrix exponential approach assisted with Krylov subspace method. The nonlinear component is treated by ordinary Newton's method yet with a much sparser Jacobian matrix that leads to substantial speedup in solving the linear system of equations. More convenient error management and adaptive control are also available through the linear and nonlinear decoupling. Furthermore, a new form of system formulation is developed to further enhance the efficiency of the proposed framework by reducing the stiffness of EM-TCAD systems via special equation and variable transforms. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new capillary electrophoresis method was developed to study the synergistic effect of superoxide dismutase and jujuboside A or B on scavenging superoxide anion radical in serum matrix respectively, in which superoxide anion radical was generated from pyrogallol autoxidation. The electrophoresis conditions, and the factors affecting the productive rate of purpurogallin, such as pyrogallol autoxidation product and the activity of superoxide dismutase, were optimized. Under optimal conditions, the content of superoxide dismutase in Gibco newborn calf serum was 7.06 mg/L, RSD was 2.01% and the average recovery was 98.4%. The values of IC50 for jujuboside A and B in the serum matrix were 157.67 and 31.60 mg/L respectively, and they both had synergy on scavenging superoxide anion radical with superoxide dismutase, but there was no the dose‐dependency on this synergy. [ABSTRACT FROM AUTHOR]