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An unprecedented Pd-catalyzed cascade alkyne insertion/Heck/C–H activation reaction of o-iodophenyl alkenyl ethers and diarylacetylenes has been developed. Diversified tetracyclic-fused dihydroindeno[2,1-b]chromenes bearing a quaternary center were constructed in an efficient, straightforward, and atom-economic way with good to excellent yields. The protocol features high bonding efficiency, operational simplicity, broad substrate scope, and easy scale-up.

A Pd-catalyzed dual C–H carbonylation of commercially available diarylamines using Co2(CO)8as a safe CO source has been developed. This methodology provides a facile approach for the synthesis of diversified acridones in moderate to good yields. The protocol features good functional group compatibility, operational safety, easy scale-up, and versatile transformations.

By virtue of the fascinating merits of low cost, rapid screening, and on-site detection, fluorescence lateral flow assays (FLFAs) have attracted considerable attention. Their detection limits are closely associated with the label probes used. The development of high-performance and robust phosphors remains a great challenge. Herein, we presented a new label probe, i.e., fluorescent carbon nanobeads (FCNBs), for FLFAs. Monodispersive, water-soluble, and highly emissive FCNBs were facilely prepared via a hydrothermal carbonization manner. Their abundant amino groups were beneficial for versatile surface functionalization. After being modified by biomolecules, the fabricated FCNB reporter probes were adopted for the construction of lateral flow test strips toward representative foodborne toxins, i.e., aflatoxin B1 (AFB1), and pathogenic bacteria, i.e., Staphylococcus aureus(S. aureus), respectively. The detection limits (0.01 ng/mL for AFB1 and 102cfu/mL for S. aureus) were about 1 or 2 orders of magnitude lower than most reported methods. Furthermore, the proposed test strips were successfully applied for the quantitative, accurate, and rapid screening of AFB1 and S. aureusin food samples. This work provided a promising label probe for FLFAs and would open the opportunity to exploit a sensing platform by modifying different ligands onto the FCNBs.

Nanomaterials with unique nanotube arrays have attracted extensive attention in the field of blood-contacting biomaterials. In this study, the regular titanium dioxide nanotube arrays were first prepared on the pure titanium surface by anodic oxidation. Subsequently, copper ions (Cu2+) and strontium ions (Sr2+) were incorporated into the nanotubes by the chelation of dopamine to improve biocompatibility. The as-prepared TiO2nanotubes had an inner diameter of about 60 nm and an outer diameter of 90–110 nm, as well as a tube length of 4–6 µm. The following annealing treatment and the incorporation of Cu2+and Sr2+had little effect on the morphology and dimensions of the nanotubes, but can significantly improve the hydrophilicity, and promote the adsorption of bovine serum albumin concurrently inhibit the adsorption of fibrinogen, showing the effect of selective protein adsorption. At the same time, loading Cu2+and Sr2+can also effectively inhibit platelet adhesion and activation, promote endothelial cell growth, and upregulate the expression of vascular endothelial growth factor and nitric oxide. Therefore, the results of this study showed that the incorporation of Cu2+and Sr2+into the TiO2nanotubes can simultaneously improve the hemocompatibility and cytocompatibility of endothelial cells, which can enlarge the application of titanium-based biomaterials in cardiovascular devices such as a stent.

In the past several years, two-phase photocatalysts, such as PDI/C3N4, ZIF/C3N4or Cu2(OH)PO4/C3N4, have been used for H2O2photo-production. Few monocomponent photocatalysts for H2O2production were reported. Among the monocomponent photocatalysts, Ti-MOF photocatalysts for H2O2photo-production have attracted much attention, although it is a challenge for Ti-MOFs to achieve good electron–hole separation. Herein, monocomponent structure NH2-MIL-125 with coexisting (111) and (001) facets was prepared as a photocatalyst for H2O2production. A “two-channel” route in the photocatalyst is formed in the frustum structure NH2-MIL-125. One channel is O2reduction by conduction band electrons on (111) facets, and the other is the valence band holes on (001) facets. This work will benefit the design of monocomponent Ti-MOF photocatalysts.

AbstractS-adenosylmethionine (SAM) is an important compound in living organisms and has a number of different roles, such as polyamine synthesis. It can also be used for the treatment of diseases. Gene targeting with homologous recombination in Komagataella phaffii(K. phaffii) created DAS1and DAS2gene knockout strains, which use the methanol pathway to generate more ATP and increase SAM production. These strains showed an increase in the flux of methanol oxidation and an increase in ATP production. The gene knockout retarded the cell growth in the late phase of induction, did not influence the total methanol consumption or the activity of SAM synthetase, but did significantly increase the yield of SAM by 43.7%. The metabolic flux of methanol oxidation is increased by DAS1and DAS2gene knockout, which leads to an increase in ATP and higher SAM production.

A Pd‐catalyzed oxidative dual C−H carbonylation has been developed starting from commercially available diarylamines, in which the Cr(CO)6served as a safe carbonyl source. This method provides a facile and atom‐economic approach toward diversified acridone derivatives in moderate to good yields, which features with good functional group compatibility, operational safety and easy scale‐up. A Pd‐catalyzed oxidative dual C−H carbonylation has been developed starting from commercially available diarylamines, in which the Cr(CO)6served as a safe carbonyl source. This method provides a facile and atom‐economic approach toward diversified acridone derivatives in moderate to good yields, which features with good functional group compatibility, operational safety and easy scale‐up.

The transmittance and conductivity of fluorine-doped tin oxide (FTO) conductive glasses are the critical factors limiting the performance of dye-sensitized solar cells (DSSCs). Here, the transmittance and conductivity of commercial FTO glasses were improved via a colloid–solution deposition planarization (CSDP) process. The process includes two steps. First, the FTO nanocrystal colloid was deposited on the FTO glasses by spin-coating. Secondly, the coated glasses were treated by FTO precursor solution. Compared to the bare FTO glasses, the modified FTO glasses by the CSDP process achieved 4% increase in transmittance (at 550 nm) and 11% decrease in sheet resistance, respectively. In addition, the modified FTO glasses can reduce the aggregation of Pt nanoparticles and improve the electrocatalytic activity of Pt counter electrodes. When the modified FTO glasses were used to assemble DSSCs, the cells got a photoelectric conversion efficiency as high as 9.37%. In contrast, the efficiency of reference cells using bare FTO substrates was about 8.24%.

The structure and catalytic properties of PtSn catalysts supported on SUZ-4 and ZSM-5 zeolite have been studied by using various experimental techniques including XRD, nitrogen adsorption, NH3-TPD, TG, H2-TPR and TPO techniques combined with propane dehydrogenation tests. It has been shown that SUZ-4-supported PtSnNa (PtSnNa/SUZ-4) was determined to be a better catalyst for propane dehydrogenation than conventional catalysts supported on ZSM-5, owing to its higher catalytic activity and stability. Dibenzothiophene poisoning experiments were performed to investigate the detailed structures of the two supported catalysts. The characterization of the two catalysts indicates that the distribution of Pt on the porous support affects the activity. In contrast to ZSM-5-supported catalysts, Pt particles on the PtSnNa/SUZ-4 are primarily dispersed over the external surface and are not as readily deactivated by carbon deposition. This is because that the strong acid sites of the SUZ-4 zeolite evidently prevented the impregnation of the Pt precursor H2PtCl6into the zeolite. In contrast, the weak acid sites of the ZSM-5 zeolite led to more of the precursor entering the zeolite tunnels, followed by transformation to highly dispersed Pt clusters during calcination. In the case of the PtSnNa/ZSM-5, the interactions between Sn oxides and the support were lessened, owing to the weaker acidity of the ZSM-5 zeolite. The dispersed Sn oxides were therefore easier to reduce to the metallic state, thus decreasing the catalytic activity for hydrocarbon dehydrogenation.

Charge recombination and transfer at the TiO2/dye/electrolyte interface play a crucial role in dye-sensitized solar cells (DSSCs). Here, a fine-controlled gold nanoparticle (Au NP) via electrodeposition incorporated into a porous TiO2photoanode and dodecanethiol molecules as an assembled monolayer capping on Au NPs was designed and prepared. The “fence-like” structure of gold thiol molecules at the TiO2/dye/electrolyte interface can not only insulate the electrolyte to suppress recombination but also make full use of the plasmon-enhanced light absorption of Au NPs. The photoanodes were characterized by X-ray photoelectron spectroscopy, UV–vis absorption, and Mott–Schottky analyses. Compared to pure TiO2, the DSSC with an interface “fence” structure achieved an efficiency (η) of 8.17%, increasing by 10.4%. The enhancement results are essentially attributed to the increase of the light-harvesting and electron collection properties, accompanying a slight promotion in the Fermi level. Furthermore, after dodecanethiol molecule treatment, the Au NPs with an intensified near-field effect also acted as electron sinks to store more electrons and exhibited a well electron-transport performance from electrochemical impedance spectroscopy analysis.

Various conditions were investigated in detail for the novel organic template-free static hydrothermal synthesis of SUZ-4 zeolite in the presence of seeds. The obtained samples were characterized by XRD (X-ray diffraction), SEM (scanning electron microscope), TG (thermal gravimetric analysis), ICP (inductively coupling plasma) elemental analysis, nitrogen sorption isotherm and surface area. The results show that pure SUZ-4 zeolites with high crystallinity are obtained in a broad window of synthesis conditions: seed mass concentration 0.2%–2%, SiO2/Al2O3molar ratio 21–25, KOH/SiO2molar ratio 0.33–0.43, H2O/SiO2molar ratio 7.14–38.1, aging time 24 h, crystallization temperature 160 °C, and crystallization time 6–10 d. Also, crystallinity and size of the rod-like SUZ-4 zeolite crystals are found to alter with the conditions.

The influences of different cations on plasmid DNA network structures on a mica substrate were investigated by atomic force microscopy (AFM). Interactions between the DNA strands and mica substrate, and between the DNA strands themselves were more strongly influenced by the complex cations (Fe(phen)₃ 2+, Ni(phen)₃2+, and Co(phen)₃3+) than by the simple cations (Mg2+, Mn2+, Ni2+, Ca2+, Co3+). The mesh height of the plasmid DNA network was higher when the complex cations were added to DNA samples. The mesh size decreased with increasing DNA concentration and increased with decreasing DNA concentration in the same cation solution sample. Hence, plasmid DNA network height can be controlled by selecting different cations, and the mesh size can be controlled by adjusting plasmid DNA concentration.