Synthesis of Spirocyclohexadienones via Palladium-Catalyzed Dearomatization of Dibenzoxaborins.

The development of Pd(II)-catalyzed dearomatization transformation of dibenzoxaborins with alkynes triggered by transmetalation from boron to palladium has been achieved, leading to the synthesis of spirocyclohexadienones, an important skeleton demonstrating potential biomedical utility. The [3 + 2] spiroannulation exhibits remarkable regioselectivity and broad substrate scope under mild reaction conditions. This methodology employs dibenzoxaborin as a substrate to establish the formal dearomatization of 2-phenylphenol, which poses a formidable energy barrier to the destruction of aromaticity.

Excellent Uniformity and Properties of Micro-Meter Thick Lead Zirconate Titanate Coatings with Rapid Thermal Annealing.

Lead zirconate titanate (PZT) films have shown great potential in piezoelectric micro-electronic-mechanical system (piezo-MEMS) owing to their strong piezoelectric response. However, the fabrication of PZT films on wafer-level suffers with achieving excellent uniformity and properties. Here, we successfully prepared perovskite PZT films with similar epitaxial multilayered structure and crystallographic orientation on 3-inch silicon wafers, by introducing a rapid thermal annealing (RTA) process.

Asymmetric [5+1] Annulation via C-H Activation/1,4-Rh Migration/Double Bond Shift Using a Transformable Pyridazine Directing Group.

-Heterocycle-assisted C-H activation/annulation reactions have provided new concepts for the construction and transformation of azacycles. In this work, we disclose a [5+1] annulation reaction using a novel transformable pyridazine directing group (DG). The DG-transformable reaction mode led to the construction of a new heterocyclic ring accompanied by transformation of the original pyridazine directing group via a C-H activation/1,4-Rh migration/double bond shift pathway, affording the skeleton of pyridazino[6,1-]quinazolines with a good substrate scope under mild conditions.

Default mode network scaffolds immature frontoparietal network in cognitive development.

The default mode network (DMN) is a workspace for convergence of internal and external information. The frontal parietal network (FPN) is indispensable to executive functioning. Yet, how they interplay to support cognitive development remains elusive.

Effective dispersion of oxidized multi-walled carbon nanotubes using a water-soluble ,-carboxymethyl chitosan non-covalent interaction.

Dispersible multi-walled carbon nanotubes (MWCNTs) in water have been widely applied in the nanotechnology field. This study reports a water-soluble ,-carboxymethyl chitosan(,-CMCS) assisted individual dispersion of oxidized multi-walled carbon nanotubes (oMWCNTs) as a dispersant. First, the dispersing agent ,-CMCS was successfully synthesized using the nucleophilic substitution of deacetylated chitosan with chloroacetic acid in an alkaline solution.

Bioinspired Optical Flexible Cellulose Nanocrystal Films with Strain-Adaptive Structural Coloration.

Recent advances of photonic crystals are driven to mechanical sensors and smart wearable devices; however, for chiral photonic cellulose nanocrystal (CNC) materials, vivid structural coloration and reversible mechanochromism like chameleon skin remain a big challenge. Here, we report a ternary co-assembly and post-UV-irradiation polymerization strategy to develop flexible and elastic CNC composite films, which, notably, have naked-eye-visible brilliant structural colors and stretching-induced color change covering a broad wavelength region at a moderate deformation (like skin). By adjusting the stretching, the film is designed as a smart skin to adapt to surrounding environments for camouflage.

Rhodium-catalyzed remote difunctionalization of arenes assisted by a relay directing group.

Rhodium-catalyzed diverse tandem twofold C-H bond activation reactions of -olefin-tethered arenes have been realized, with unsaturated reagents such as internal alkynes, dioxazolones, and isocyanates being the coupling partner as well as a relay directing group which triggers cyclization of the -olefin group under oxidative or redox-neutral conditions. The reaction proceeded initial -C-H activation assisted by a built-in directing group in the arene, and the -incorporation of the unsaturated coupling partner simultaneously generated a relay directing group that allows sequential C-H activation at the -position and subsequent cyclization of the -olefins. The overall reaction represents C-C or N-C difunctionalization of the arene with the generation of diverse 2,3-dihydrobenzofuran platforms.

Water-soluble carboxymethyl chitosan (WSCC)-modified single-walled carbon nanotubes (SWCNTs) provide efficient adsorption of Pb(ii) from water.

Nanocomposites play a key role in the removal of toxic metal(loid)s from environmental water. In this study, we investigated the adsorption capability of water-soluble carboxymethyl chitosan (WSCC)-modified functionally oxidized single walled carbon nanotubes (oSWCNTs) for rapid and efficient removal of toxic Pb(ii) from water. The WSCC-oSWCNTs nanocomposite was prepared by an acid treatment of SWCNTs followed by an ultrasonic dispersion process using WSCC as dispersant.

Achieving a Record-High Capacitive Energy Density on Si with Columnar Nanograined Ferroelectric Films.

High energy density dielectric film capacitors are desirable in modern electronic devices. Their miniaturization and integration into Si-based microsystems create opportunities for in-circuit energy supply, buffering, and conditioning. Here, we present a CMOS (complementary metal oxide semiconductor)-compatible route for the fabrication of BaTiO film capacitors on Si with a record-high recoverable energy density and good efficiency (∼242 J/cm and ∼76% at 8.

Effects of different pesticides treatments on the nutritional quality of kiwifruit.

Pesticides are widely used in the process of kiwifruit growth to promote fruit expansion. This study was aimed to assess the effects of pesticides on the quality of kiwifruit by applying high and normal concentrations of forchlorfenuron (CPPU) and thidiazuron (TDZ) to "Xuxiang" (XX) green kiwifruit and "Jinyan" (JY) gold kiwifruit. Sixty kiwifruit trees were used to comprehensively evaluate the effects on the pulp and whole kiwifruit.

High Energy Performance Ferroelectric (Ba,Sr)(Zr,Ti)O Film Capacitors Integrated on Si at 400 °C.

BaTiO-based ferroelectrics have been extensively studied due to their large dielectric constants and a high saturated polarization, which have the potential to store or supply electricity of very high energy and power densities. In order to further improve the energy efficiency η and the recyclable energy density , an A, B-site co-doped (Ba,Sr)(Zr,Ti)O ceramic target was used for sputter deposition of film capacitor structures on Si. This film composition reduces the remnant polarization , while the choice of a low-temperature, templated sputtering process facilitates the formation of high-density arrays of columnar nanograins (average diameter ∼20 nm) and grain boundary dead layers.

Triazolotriazine-based thermally activated delayed fluorescence materials for highly efficient fluorescent organic light-emitting diodes (TSF-OLEDs).

Thermally activated delayed fluorescence (TADF) sensitized fluorescent organic light-emitting diodes (TSF-OLEDs) have shown great potential for the realization of high efficiency with low efficiency roll-off and good color purity. However, the superior examples of TSF-OLEDs are still limited up to now. Herein, a trade-off strategy is presented for designing efficient TADF materials and achieving high-performance TSF-OLEDs via the construction of a new type of triazolotriazine (TAZTRZ) acceptor.

First record of the tropical genus Rambutanura (Collembola: Neanuridae: Neanurinae) in Palearctic, with description of a new species from China.

Genus Rambutanura Deharveng, 1988 of subfamily Neanurinae is herein recorded and a new species is described from China. A key to the species of the whole world of the genus is provided. In order to determine the new species, a new diagnosis within the genus Rambutanura Deharveng, 1988 is proposed.

Demonstration of ultra-high recyclable energy densities in domain-engineered ferroelectric films.

Dielectric capacitors have the highest charge/discharge speed among all electrical energy devices, but lag behind in energy density. Here we report dielectric ultracapacitors based on ferroelectric films of Ba(Zr,Ti)O which display high-energy densities (up to 166 J cm) and efficiencies (up to 96%). Different from a typical ferroelectric whose electric polarization is easily saturated, these Ba(Zr,Ti)O films display a much delayed saturation of the electric polarization, which increases continuously from nearly zero at remnant in a multipolar state, to a large value under the maximum electric field, leading to drastically improved recyclable energy densities.

[Experimental study on the anti-liver fibrosis effect of guzhang tablet in rats].

Objective: To observe the anti-liver-fibrosis effect of Guzhang Tablet (GZT) and to explore its mechanism.

Methods: Fifty female rats, weighing 200-220 g were randomly divided into the blank control group, the model group, the small dosage GZT group, the large dosage GZT group and the Biejiajian Pill (BJJP) group, 10 rats in each group. The changes of related serum enzymes, liver-fibrosis marker, oxygen free radical and liver tissue pathology were observed after 8 weeks of treatment.