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381.
Owing to the capacity boost from oxygen redox activities, Li‐rich cation‐disordered rocksalts (LRCDRS) represent a new class of promising high‐energy Li‐ion battery cathode materials. Redox‐inactive transition‐metal (TM) cations, typically d0 TM, are essential in the formation of rocksalt phases, however, their role in electrochemical performance and cathode stability is largely unknown. In the present study, the effect of two d0 TM (Nb5+ and Ti4+) is systematically compared on the redox chemistry of Mn‐based model LRCDRS cathodes, namely Li1.3Nb0.3Mn0.4O2 (LNMO), Li1.25Nb0.15Ti0.2Mn0.4O2 (LNTMO), and Li1.2Ti0.4Mn0.4O2 (LTMO). Although electrochemically inactive, d0 TM serves as a modulator for oxygen redox, with Nb5+ significantly enhancing initial charge storage contribution from oxygen redox. Further studies using differential electrochemical mass spectroscopy and resonant inelastic X‐ray scattering reveal that Ti4+ is better in stabilizing the oxidized oxygen anions (On?, 0 < n < 2), leading to a more reversible O redox process with less oxygen gas release. As a result, much improved chemical, structural and cycling stabilities are achieved on LTMO. Detailed evaluation on the effect of d0 TM on degradation mechanism further suggests that proper design of redox‐inactive TM cations provides an important avenue to balanced capacity and stability in this newer class of cathode materials.  相似文献   
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Magnetic Resonance Materials in Physics, Biology and Medicine - To investigate whether varied or repeated b-values provide better diffusion MRI data for discriminating cortical areas with a...  相似文献   
383.
Characterization of the N-glycosylation present in the Fc region of therapeutic monoclonal antibodies requires rapid, high-resolution separation methods to guarantee product safety and efficacy during all stages of process development. Determination of fucosylated oligosaccharides is particularly important during clone selection, product characterization, and lot release as fucose has been shown to adversely affect the ability of mAbs to induce antibody dependent cellular cytotoxicity (ADCC). Here, we apply a general capillary electrophoresis optimization strategy to separate functionally relevant fucosylated and afucosylated glycans on mononclonal antibody products in the presence of several high mannose oligosaccharides. The N-glycans chosen represent those most commonly reported on CHO cell derived therapeutic antibodies. A rapid (<7 min) high-resolution separation of 12 commonly reported and functionally important IgG glycans was developed by systematically evaluating the effects of selectivity (boric acid) and efficiency (linear polyacrylamide) enhancing additives. The approach can be used to rapidly optimize capillary electrophoresis separation of other glycan mixtures. Following optimization, the method was applied to overnight sample processing for automated 96 well plate-based glycosylation analyses of two nonproprietary therapeutic monoclonal antibodies, demonstrating ruggedness and suitability for high-throughput process and product monitoring applications.  相似文献   
384.
This paper presents the application of the Schapery viscoelastic and the Perzyna viscoplastic models to strain recovery data of polypropylene. In a previous study, the recovery of strain after monotonic uniaxial tensile loading was measured to gather information on the viscoelasticity and viscoplasticity. The viscoplastic strains from several load histories were determined and are used to calibrate the viscoplastic model. The parameters of the one-dimensional Schapery model are then found by nonlinear optimization using the strain recovery history. The prediction of stress relaxation and creep behavior is investigated.  相似文献   
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Samples of kidney, blood, lungs, hair, heart, liver, spleen, muscle, ear, rib, skin and faeces were obtained from 200 fattened pigs in 10 abattoirs across Hungary. These were analysed in triplicate for cadmium and lead concentrations by atomic absorption spectrophotometry. The highest concentrations of cadmium were found in the kidney, followed by hair and faeces and then liver, heart and lungs. Lead concentrations were greater in the hair and faeces than other tissues. Both lead and cadmium concentrations in meat and offal were below the legal limits. There was more variation in lead than cadmium concentrations between abattoirs, and across abattoirs there was no correlation between concentrations of the two elements. Blood lead concentration was correlated with the lead concentration in bone, kidney, liver, spleen and lungs, and was a better indicator of lead contamination than hair lead concentration. The cadmium concentrations of the kidney, liver, spleen, lungs and faeces were highly correlated, and it is suggested that faeces is the best on‐farm indicator of cadmium contamination. Across animals, blood cadmium correlated less closely with the cadmium concentration of the body tissues than it did with the lead concentration, demonstrating positive interaction between the two elements. By contrast, hair and to a lesser extent bone cadmium concentrations were negatively correlated with the lead concentration of most tissues. It is concluded that lead and cadmium concentrations in pigs are best monitored in blood and faeces concentrations, respectively. Copyright © 2005 Society of Chemical Industry  相似文献   
388.
The anti-yeast activities of four essential oils (EOs) from clary sage, juniper, lemon and marjoram against wild-type isolates of the food-related yeasts Geotrichum candidum, Pichia anomala, Saccharomyces cerevisiae and Schizosaccharomyces pombe in malt extract (ME) medium, apple juice and milk were investigated. Minimal inhibitory concentrations (MICs) for the EOs and their main components were determined and the checkerboard method was used to calculate fractional inhibitory concentration (FIC) indices for the combinations of EOs or components. The most sensitive yeast was S. pombe (MICs of 0.0625-0.125 μl/ml) while G. candidum proved to be the most insensitive (MICs of 0.5-2 μl/ml). In general, the lag phases were lengthened by increasing EO concentrations, while significant reduction of growth rates was obtained only at the highest EO concentrations. The anti-yeast effects of the EOs were good in the acidic pH range optimal for yeasts growth. Combinations of juniper and clary sage EOs resulted in additive effects in the case of S. cerevisiae and G. candidum, but all other combinations showed no interaction. The combination of α-pinene and limonene led to synergism, while the combination of α-pinene with linalool resulted in an additive effect. Cloudy apple juice protected the yeasts against the effect of lemon EO: the lag phases were shorter and the growth rates higher than in clear apple juice. Lemon EO decreased the growth rate of G. candidum in skimmed milk in a dose-independent manner. Our results show that by adding lemon EO to clear apple juice a new, harmonic taste can be achieved and open storage time could be prolonged.  相似文献   
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