Constructing core/shell nanoarrays with optimal structure and composition can maximize solar light utilization. In the present work, a distinct regular array of SiC/TiO.sub.2 core/shell nanoarray ...photoanodes with improved charge separation is successfully achieved through two sequential steps of electrochemical etching and atomic layer deposition. The suitable band offset between SiC and TiO.sub.2 results in forming a type-II heterojunction at the SiC/TiO.sub.2 interface, which efficiently promotes electron-hole separation. Under simulated sunlight illumination (100 mW/cm.sup.2), the SiC/TiO.sub.2 nanoarray composite photoanode exhibits a significantly improved photocurrent of 3.62 mA/cm.sup.2 at 1.4 V versus Ag/AgCl, which demonstrates significantly increased photoelectrochemical (PEC) activity compared to the intrinsic SiC photoanode. The significant enhancement of PEC behaviors is mainly assigned to the improved electron-hole separation at the surface of the junction, combined with the synergistic effect of the highly oriented nanochannel array configuration, single-crystal character of the etched entire SiC nanoarray film, as well as the incorporation of N dopants.
The separators with excellent thermal stability and electrolyte wettability are pivotal for ensuring the safety and performance of lithium-ion batteries (LIBs). Poly (ether ether ketone) (PEEK) is a ...potential separator material that meets these criteria. However, the poor solubility and high melting temperature of PEEK limit its practical production and application. Herein, we report a safe and convenient strategy to fabricate lithiated poly (ether ether ketone) (LPEEK) separators via lithiation of PEEK and thermally induced phase separation below the melting point. And the pore structure of LPEEK separators can be regulated by the amount of polyvinylpyrrolidone. Compared with commercial polypropylene (PP) separators and other PEEK separators, our LPEEK separators exhibit excellent thermal stability (LPEEK, almost no change at 200 °C; PP, shrink 4.4% at 100 °C) and electrolyte wettability (electrolyte contact angle: LPEEK, 0°; PP, 37.9°). Meanwhile, the LPEEK separators can still be used normally after 200 °C high-temperature treatment and are promising candidates for the LIB separators used at high temperatures. The proposed method holds promise for the industrial production of PEEK separators.
Parameters controlling the reduction of nickel hydrotalcite-based catalysts have been investigated in order to optimize the activity of the catalyst for CO.sub.2 methanation. Beside the variation of ...temperature and duration in the reduction process of the catalysts with hydrogen, two different reduction modes have been explored. The first one is the direct reduction of the dried uncalcined hydrotalcite-based precursor material whereas the second one is given by the reduction of the same type of precursor material but having been subjected to a calcination step prior to reduction. The corresponding kinetic measurements for the two principally different catalyst preparation schemes reveal that omitting the calcination step can largely be beneficial. Standard characterization data (XRD, BET, TG-FTIR, XPS) for the different catalytic materials will be presented.
The influence of nanoscale surface topography on protein adsorption is highly important for numerous applications in medicine and technology. Herein, ferritin adsorption at flat and nanofaceted, ...single-crystalline Alsub.2Osub.3 surfaces is investigated using atomic force microscopy and X-ray photoelectron spectroscopy. The nanofaceted surfaces are generated by the thermal annealing of Alsub.2Osub.3 wafers at temperatures above 1000 °C, which leads to the formation of faceted saw-tooth-like surface topographies with periodicities of about 160 nm and amplitudes of about 15 nm. Ferritin adsorption at these nanofaceted surfaces is notably suppressed compared to the flat surface at a concentration of 10 mg/mL, which is attributed to lower adsorption affinities of the newly formed facets. Consequently, adsorption is restricted mostly to the pattern grooves, where the proteins can maximize their contact area with the surface. However, this effect depends on the protein concentration, with an inverse trend being observed at 30 mg/mL. Furthermore, different ferritin adsorption behavior is observed at topographically similar nanofacet patterns fabricated at different annealing temperatures and attributed to different step and kink densities. These results demonstrate that while protein adsorption at solid surfaces can be notably affected by nanofacet patterns, fine-tuning protein adsorption in this way requires the precise control of facet properties.
The process Formula omitted is studied in the experiment at the VEPP-2000 Formula omitted collider with the SND detector. The technique of the time measurements in the multichannel NaI(Tl) ...electromagnetic calorimeter is used to select Formula omitted events. The value of the measured cross section in the center-of-mass energy range from 1.894 to 2 GeV varies from 0.5 to 0.35 nb. The effective neutron timelike form factor is derived from the measured cross section and compared with the proton form factor. The ratio of the neutron electric and magnetic form factors is obtained from the analysis of the antineutron polar angle distribution and found to be consistent with unity.
Semimetal bismuth with plasmonic properties has attracted more and more interest to enhance photocatalytic activity. Herein Bi/Bi.sub.2WO.sub.6 composites catalyst was successfully synthesized via a ...simple two-step route in solvothermal reaction. Compared with pure Bi.sub.2WO.sub.6, the photocatalytic degradation efficiency of gasphase toluene of the Bi/Bi.sub.2WO.sub.6 composites is significantly increased from 44 to 93%, and the degradation efficiency increased by more than two times. From the analysis of UV-vis diffuse reflectance spectra, it is obvious that the optical absorption in visible light region of Bi/Bi.sub.2WO.sub.6 composites has significantly enhanced compared to pure Bi.sub.2WO.sub.6, which is due to the surface plasmon resonance (SPR) of Bi nanoparticles on the surface of pure Bi.sub.2WO.sub.6. The dramatically enhanced activity could be attributed to the synergistic effect of the strong SPR of Bi metals and the enhancement of charge separation efficiency caused by the interfacial interaction between Bi metal and Bi.sub.2WO.sub.6.
Purpose The tissue-to-plasma partition coefficient (K.sub.p) describes the extent of tissue distribution in physiologically-based pharmacokinetic (PBPK) models. Constant-rate infusion studies are ...common for experimental determination of the steady-state K.sub.p,ss, while the tissue-plasma concentration ratio (C.sub.T/C.sub.p) in the terminal phase after intravenous doses is often utilized. The Chen and Gross (C&G) method converts a terminal slope C.sub.T/C.sub.p to K.sub.p,ss based on assumptions of perfusion-limited distribution in tissue-plasma equilibration. However, considering blood flow (Q.sub.T) and apparent tissue permeability (f.sub.upPS.sub.in) in the rate of tissue distribution, this report extends the C&G method by utilizing a fractional distribution parameter (f.sub.d). Methods Relevant PBPK equations for non-eliminating and eliminating organs along with lung and liver were derived for the conversion of C.sub.T/C.sub.p values to K.sub.p,ss. The relationships were demonstrated in rats with measured C.sub.T/C.sub.p and K.sub.p,ss values and the model-dependent f.sub.d for 8 compounds with a range of permeability coefficients. Several methods of assessing K.sub.p were compared. Results Utilizing f.sub.d in an extended C&G method, our estimations of K.sub.p,ss from C.sub.T/C.sub.p were improved, particularly for lower permeability compounds. However, four in silico methods for estimating K.sub.p performed poorly across tissues in comparison with measured K.sub.p values. Mathematical relationships between K.sub.p and K.sub.p,ss that are generally applicable for eliminating organs with tissue permeability limitations necessitates inclusion of an extraction ratio (ER) and f.sub.d. Conclusion Since many different types/sources of K.sub.p are present in the literature and used in PBPK models, these perspectives and equations should provide better insights in measuring and interpreting K.sub.p values in PBPK.
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