SnO -based lithium-ion batteries have low cost and high energy density, but their capacity fades rapidly during lithiation/delithiation due to phase aggregation and cracking. These problems can be mitigated by using highly conducting black SnO , which homogenizes the redox reactions and stabilizes fine, fracture-resistant Sn precipitates in the Li O matrix. Such fine Sn precipitates and their ample contact with Li O proliferate the reversible Sn → Li Sn → Sn → SnO /SnO cycle during charging/discharging. SnO electrode has a reversible capacity of 1340 mAh g and retains 590 mAh g after 100 cycles. The addition of highly conductive, well-dispersed reduced graphene oxide further stabilizes and improves its performance, allowing 950 mAh g remaining after 100 cycles at 0.2 A g with 700 mAh g at 2.0 A g . Conductivity-directed microstructure development may offer a new approach to form advanced electrodes.

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A new sensitive fluorescent probe with long analytical wavelengths for γ-glutamyl transpeptidase (GGT) assay has been developed by incorporating the γ-glutamyl group as a recognition unit into the fluorophore of cresyl violet (CV). The detection mechanism is based on the GGT-catalyzed cleavage of the γ-glutamyl group, followed by the release of CV, which leads to a distinct color change from light yellow to pink and a large fluorescence enhancement at 615 nm (λex = 585 nm). Under the optimized conditions, the fluorescence intensity of the probe is directly proportional to the activity of GGT in the range of 1-50 U/L with a detection limit of 5.6 mU/L. By virtue of its high sensitivity and long analytical wavelengths, the probe has been used to directly determine GGT in human serum samples from both healthy people and liver cancer patients, and the obtained results accord well with those acquired by commercial GGT fluorometric assay kit. The probe has also been employed to image endogenous GGT in living cells. Notably, with our probe the expression level of GGT in HepG2 cells under the action of sodium butyrate (an anticancer drug) was studied by fluorescence confocal microscopy, revealing that sodium butyrate can induce the upregulation of GGT in HepG2 cells in a dose- and time-dependent manner. This behavior of sodium butyrate has further been confirmed by lysate assay and inhibitor experiment. The proposed probe is rather simple and may find a wide use in the determination of GGT in clinical and biological samples.

is concerned, the present finding bears essential implications for applying the superplastic forming of ceramics into a costeffective industrial production of complex shaped silicon nitride-based components, and for production of other polycrystalline materials that are sintered to full density via a liquid-phase sintering process. ExperimentalThe starting powders were Si 3 N 4 (Ube, SN-E10), AlN (HC Starck, Grade C), Al 2 O 3 , Y 2 O 3 , and Yb 2 O 3 (Johnson Matthey Chemicals Ltd.). When calculating the compositions, corrections were made for the small amounts of oxygen present in the Si 3 N 4 and AlN precursor powders. The starting materials, in batches of 50 g, were ball milled in water-free propanol for 24 h, using sialon milling media. The dried powders were consolidated in vacuum in an SPS apparatus, Dr. Sinter 2050 (Sumitomo Coal Mining Co. Ltd., Japan). The powder precursors were loaded in cylindrical carbon dies with an inner diameter of 12 mm. The samples were heated via a pulsed direct current that passed through the pressure die, i.e., the pressure die also acted as a heating source. The temperature was automatically raised to 600 C over a period of 3 min, and from this point on it was monitored and regulated by an optical pyrometer focused on the surface of the die. A heating rate of 200 C min ±1 was used, and a uniaxal pressure of 50 MPa was applied from the start to the end of the sintering cycle. The set-up allowed a cooling rate of~400 C min ±1 in the temperature range 1800±1000 C.The compressive deformation tests were carried out both in the SPS apparatus and in a conventional HP chamber heated by surrounding graphite heating elements. The fully densified cylindrical samples, with a diameter of 12 mm and a height of~6 mm, were loaded in a graphite die with an inner diameter of 20 mm, and deformed by applying a compressive stress through the oppositely moving graphite punches.The crystalline phase assemblies present in the sintered ceramics were determined from Guinier±Hägg X-ray powder diffraction patterns, using monochromatic Cu Ka radiation and Si as an internal standard. Both fractured and polished surfaces of the samples were examined in a scanning electron microscope (Jeol JSM 880) equipped with an energy-dispersive spectrometer (EDS, LINK ISIS). In order to obtain the best contrast between different phases, the microscopy images were recorded in back-scattered electron mode, where the a-sialon and Yb/Y-enriched intergranular glassy phases show medium gray and bright contrasts, respectively, whereas b-sialon, if present, appears with in dark (black) contrast. The amounts of intergranular glassy phase were evaluated with an image-analyzing package supplied with the LINK ISIS system. The contrast difference between the a/b-sialon grains and the Yb/Y-containing glassy phase was used to estimate the phase content in vol.-%, which was assumed valid for the whole sample volume. The estimated minimum and maximum amounts of glassy phase gave an error of ± 1 %.

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Advancements in chromatographic separation are critical to in-depth top-down proteomics of complex intact protein samples. Reversed-phase liquid chromatography is the most prevalent technique for top-down proteomics. However, in cases of high complexities and large dynamic ranges, 1D-RPLC may not provide sufficient coverage of the proteome. To address these challenges, orthogonal separation techniques are often combined to improve the coverage and the dynamic range of detection. In this study, a “salt-free” high-pH RPLC was evaluated as an orthogonal dimension of separation to conventional low-pH RPLC with top-down MS. The RPLC separations with low-pH conditions (pH=2) and high-pH conditions (pH=10) were compared to confirm the good orthogonality between high-pH and low-pH RPLC’s. The offline 2D RPLC-RPLC-MS/MS analyses of intact E. coli samples were evaluated for the improvement of intact protein identifications as well as intact proteoform characterizations. Compared to the 163 proteins and 328 proteoforms identified using a 1D RPLC-MS approach, 365 proteins and 886 proteoforms were identified using the 2D RPLC-RPLC top-down MS approach. Our results demonstrate that the 2D RPLC-RPLC top-down approach holds great potential for in-depth top-down proteomics studies by utilizing the high resolving power of RPLC separations and by using mass spectrometry compatible buffers for easy sample handling for online MS analysis.

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