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391.
Lithium and sodium metal batteries continue to occupy the forefront of battery research. Their exceptionally high energy density and nominal voltages are highly attractive for cutting-edge energy storage applications. Anode-free metal batteries are also coming into the research spotlight offering improved safety and even higher energy densities than conventional metal batteries. However, uneven metal nucleation and growth which leads to dendrites continues to limit the commercialisation of conventional and anode-free metal batteries alike. This review connects models and theories from well-established fields in metallurgy and electrodeposition to both conventional and anode-free metal batteries. These highly applicable models and theories explain the driving forces of uneven metal growth and can inform future experiment design. Finally, the models and theories that are most relevant to each anode-related cell component are identified. Keeping these specific models and theories in mind will assist with rational design for these components.  相似文献   
392.
Biodegradable electrospun sponges are of interest for various applications including tissue engineering, drug release, dental therapy, plant protection, and plant fertilization. Biodegradable electrospun poly(l -lactide)/poly(ε-caprolactone) (PLLA/PCL) blend fiber-based sponge with hierarchical pore structure is inherently hydrophobic, which is disadvantageous for application in tissue engineering, fertilization, and drug delivery. Contact angles and model studies for staining with a hydrophilic dye for untreated, plasma-treated, and surfactant-treated PLLA/PCL sponges are reported. Thorough hydrophilization of PLLA/PCL sponges is found only with surfactant-treated sponges. The MTT assay on the leachates from the sponges does not indicate any cell incompatibility. Furthermore, the cell proliferation and penetration of the hydrophilized sponges are verified by in vitro cell culture studies using MG63 and human fibroblast cells.  相似文献   
393.
The solvation of large hydrophobic solutes, modeled as repulsive and attractive Gay-Berne oblate ellipsoids, is characterized in several modified water liquids using the SPC/E model as the reference water fluid. We find that small amounts of attraction between the Gay-Berne particle and any model fluid result in wetting of the hydrophobic surface. However, significant differences are found among the modified and SPC/E water models and the critical distances in which they dewet the hydrophobic surfaces of pairs of repulsive Gay-Berne particles. We find that the dewetting trends for repulsive Gay-Berne particles in the various model liquids correlate directly with their surface tensions, the widths of the interfaces they form, and the openness of their network structure. The largest critical separations are found in liquids with the smallest surface tensions and the broadest interfaces as measured by the Egelstaff-Widom length.  相似文献   
394.
A charge‐carrier density dependent mobility has been predicted for amorphous, glassy energetically disordered semiconducting polymers, which would have considerable impact on their performance in devices. However, previous observations of a density dependent mobility are complicated by the polycrystalline materials studied. Here charge transport in field‐effect transistors and diodes of two amorphous, glassy fluorene‐triarylamine copolymers is investigated, and the results explored in terms of a charge‐carrier density dependent mobility model. The nondispersive nature of the time‐of‐flight (TOF) transients and analysis of dark injection transient results and transistor transfer characteristics indicate a charge‐carrier density independent mobility in both the low‐density diode and the high‐density transistor regimes. The mobility values for optimized transistors are in good agreement with the TOF values at the same field, and both have the same temperature dependency. The measured transistor mobility falls two to three orders of magnitude below that predicted from the charge‐carrier density dependent model, and does not follow the expected power‐law relationship. The experimental results for these two amorphous polymers are therefore consistent with a charge‐carrier density independent mobility, and this is discussed in terms of polaron‐dominated hopping and interchain correlated disorder.  相似文献   
395.
Elemental depth profiling by glow discharge optical emission spectroscopy has been used to characterize the corrosion products on AA2024‐T3. In previous work, the aluminium, oxygen and copper depth profiles were shown to provide information regarding surface roughening, the thickness of corroded layers and extent of copper de‐alloying/relocation. Nitrogen, sulfur, phosphorus and chromium depth profiles were examined in the hope of detecting inhibitor species within the corroded/altered layers after 5 h of exposure to a corrosive solution. In the present work, the study is extended to longer exposure time. The work presents a further study of the leaching of benzotriazole from the coating matrix or from nanocontainers during various times of exposure to a corrosive environment. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
396.
Guanidinium is a versatile functional group with unique properties. In biological systems, hydrogen-bonding and electrostatic interactions involving the arginine side chains of proteins are critical to stabilise complexes between proteins and nucleic acids, carbohydrates or other proteins. Leading examples of artificial receptors for carboxylates, phosphates and other oxoanions, such as sulfate or nitrate are highlighted in this tutorial review, addressed to readers interested in biology, chemistry and supramolecular chemistry.  相似文献   
397.
We report the unambiguous detection of a sequence of Hepatitis C Virus (HCV) at concentrations down to the fractional pM range using Single Wall Carbon Nanotube (SWNT) Field Effect Transistor (FET) devices functionalized with Peptide Nucleic Acid (PNA).  相似文献   
398.
While supercritical fluid chromatography was developed over 50 years ago, it is only over the past 15 to 20 years that it has become routinely utilized. Along with the commercialization of a new generation of instruments, during the last 20 years supercritical fluid chromatography has improved performance, reliability, and robustness. Supercritical fluid chromatography is fully compatible with mass spectrometric techniques. This review compiles the application of supercritical fluid chromatography separations coupled to mass spectrometry instrumentation for the exploration, profiling, and quantitation of metabolites during the last two decades. The selection of metabolites chosen for this article have direct applications in preclinical models of disease and clinical applications as potential biomarkers of disease including lipids, steroid hormones, bile acids, polar metabolites, peptides, and proteins.  相似文献   
399.

The effect of ethylene vinyl acetate (EVA) concentration and vinyl acetate (VA) content of EVA on the mechanical, morphological, and rheological properties of bio-based high-density polyethylene (BioPE)/EVA blends was investigated. The blends were characterized by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, and rheological measurements under oscillatory shear flow. The degree of crystallinity of BioPE decreased with the increase in the EVA concentration and was unaffected with the increase in the VA content. DMTA results showed a decrease in the storage modulus (E′) with the increase in EVA content and that the BioPE/EVA19 blends showed higher E′ values than BioPE/EVA28 blend. The impact strength substantially increased with the addition of EVA concentration above 5 mass% and was higher for the blends containing the highest VA content. The blends containing a higher content of VA exhibited the higher EVA dispersed phase domain size, which increased with the increase in EVA concentration. The complex viscosity increased with the increase in the EVA content, being higher for the BioPE/EVA blends containing higher VA content. The storage modulus increased, at low frequencies, with the increase in the EVA content and can be ascribed to the increase in the EVA dispersed phase domain size.

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400.
The characterization sections of biologics license applications (BLAs) approved by the United States Food and Drug Administration (FDA) between 2000 and 2015 were investigated to examine the extent of the use of mass spectrometry. Mass spectrometry was found to be integral to the characterization of these biotherapeutics. Of the 80 electronically submitted monoclonal antibody and protein biotherapeutic BLAs included in this study, 79 were found to use mass spectrometric workflows for protein or impurity characterization. To further examine how MS is being used in successful BLAs, the applications were filtered based on the type and number of quality attributes characterized, the mass spectrometric workflows used (peptide mapping, intact mass analysis, and cleaved glycan analysis), the methods used to introduce the proteins into the gas phase (ESI, MALDI, or LC-ESI), and the specific types of instrumentation used. Analyses were conducted over a time course based on the FDA BLA approval to determine if any trends in utilization could be observed over time. Additionally, the different classes of protein-based biotherapeutics among the approved BLAs were clustered to determine if any trends could be attributed to the specific type of biotherapeutic.
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