The production of CH3OH from the photocatalytic CO2 reduction reaction (PCRR) presents a promising route for the clean utilization of renewable resources, but charge recombination, an unsatisfying stability and a poor selectivity limit its practical application. In this paper, we present the design and fabrication of 0D/2D materials with polymeric C3N4 nanosheets and CdSe quantum dots (QDs) to enhance the separation and reduce the diffusion length of charge carriers. The rapid outflow of carriers also restrains self‐corrosion and consequently enhances the stability. Furthermore, based on quantum confinement effects of the QDs, the energy of the electrons could be adjusted to a level that inhibits the hydrogen evolution reaction (HER, the main competitive reaction to PCRR) and improves the selectivity and activity for CH3OH production from the PCRR. The band structures of photocatalysts with various CdSe particle sizes were also investigated quantitatively to establish the relationship between the band energy and the photocatalytic performance. 相似文献
The experimental results of imaging through flesh tissue using fs electronic holographic gating method is reported. In the experiment, Ti: sapphire mode-locked laser is used as light source, of which the repetition rate is 100 MHz, central wavelength 800 nm, duration of pulse 20 fs, output power 80 mW. Tissue is a 7 mm thick chicken slice, and the imaged object is a metal wire with diameter of 0.5 mm. A general CCD is used to record holograms and a clear image of metal wire is obtained. Several relevant problems are discussed. 相似文献
This study evaluated the feasibility of using commercially available immortalized cell lines in building an in vitro blood-brain
barrier (BBB) co-culture model for preliminary drug development studies. Astrocytes-derived acellular extracellular matrix
(aECM) was introduced in the co-culture model to provide a novel biomimetic basement membrane for the endothelial cells to
form tight junctions. Trans-Endothelial Electrical Resistance (TEER) and solute mass transport studies quantitatively evaluated
the tight junction formation. Immuno-fluorescence microscopy and Western blot analysis qualitatively verified the expression
of occludin, one of the tight junction proteins on the samples. Experimental data from a total of 13 experiments conclusively
showed that the novel BBB in vitro co-culture model with aECM (CO + aECM) is promising in terms of establishing tight junction
formation represented by TEER values, transport profiles, and tight junction protein expression when compared with traditional
co-culture (CO) model setup or the endothelial cells cultured alone (EC). In vitro colorimetric sulforhodamine B (SRB) assay
also revealed that the “CO + aECM” samples resulted in less cell loss on the basal sides of the insert membranes than traditional
co-culture models. Our novel approach using immortalized cell lines with the addition of aECM was proven to be a feasible
and repeatable alternative to the traditional BBB in vitro modeling. 相似文献
A new electrospinning process was developed for preparing TiO2 nanofibers using a water-soluble Ti-precursor, [bis(kappa1O-hydroxo)(bis(kappa2O,O′-lactato)titanium(IV)] commonly known as titanium(IV) bis (ammonium lactato) dihydroxide (TiBALDH). The importance of the study is justified by the fact that Ti-precursors used for electrospinning, sol–gel, hydrothermal and other fiber synthesis processes are mostly non-water soluble. Accordingly, anatase TiO2 nanofibers of diameter between 20 and 140 nm were synthesized by electrospinning and annealing. Polyvinylpyrrolidone (PVP) and different concentrations of TiBALDH were dissolved in a mixture of water, ethyl alcohol and acetic acid to optimize the electrospinning conditions. The thermal decomposition and fragmentation of PVP, TiBALDH and the fibers with 50% mass fraction of TiBALDH were studied by TGA-MS measurements. The fibers were then annealed at 1 °C min?1 until 600 °C. The TiO2 fibers were characterized using SEM–EDX, FTIR and XRD