Hierarchical supramolecules composed of starch-based nanocluster aggregates with light-responsive mechanical strain for remotely rapid and precise actuation.

Hierarchical supramolecular systems, characterized by nanoscale sensitivity and macroscopic tangible changes, offer promising perspectives for the design of remotely controllable, rapid, and precise actuation materials, serving as a potential substitution for non-intelligent and complex actuation switches. Herein, we reported on the disassembly of orderly and rigid starch helical covalent structures, and their subsequent reassembly into a hierarchical supramolecular gel composed of nanocluster aggregates, integrating supramolecular interactions of three different scales. The incorporation of photo-sensitive FeIIITA, a complex of trivalent iron ions and tannic acid, significantly enhances the photo-responsive strain capacity of the hierarchical supramolecular gel. The supramolecular gel exhibits its features in a rapid light-responsive rate of hardness and viscosity, enabling the actuation of objects within 22 s under light exposure when employed as a remote actuation switch. Meanwhile, this actuation mechanism of the hierarchical supramolecular gel also has a promising perspective in precise control, identifying and actuating one of the two objects in distances of 0.8 mm even smaller scales. Our work provides a reliable reference for replacing complex actuation switches with intelligent materials for remote, rapid, and accurate actuation, and offers valuable insights for actuation in harsh and vacuum outdoor environments.

Rationally designed Mn2O3@ZnMn2O4/C core-shell hollow microspheres for aqueous zinc-ion batteries.

Manganese-based oxides are common cathode materials for aqueous zinc ion batteries (AZIBs) because of their great capacity and high working voltage. However, the sharp decline of capacity caused by the dissolution of manganese-based cathode materials and the low-rate performance restrict their development. To address these problems, unique core-shell structured Mn2O3@ZnMn2O4/C hollow microspheres are reported as an ideal cathode material for AZIBs. Benefiting from the hollow structure, the zeolitic imidazolate framework (ZIF)-derived carbon and ZnMn2O4. Its application in AZIBs as the cathode demonstrates its satisfactory rate performance, high cycle stability, and excellent reversibility. Its high reversible capacity is remarkable, which reaches its maximum of 289.9 mA h g-1 at 200 mA g-1 and maintains a capacity of 203.5 mA h g-1 after cycling for 700 times at 1000 mA g-1. These excellent performances indicate that this material is a potential cathode material of AZIBs.

[Leaching characteristics of sulfadiazine and sulfamethoxazole in soil column].

Leaching characteristics and influencing factors of the typical sulfa antibiotics-sulfadiazine and sulfamethoxazole were studied by soil column experiments. The results showed that the leaching rate increased and the residues of sulfa antibiotics in soil column decreased as the soil profile depth increased. The residual concentration of sulfa antibiotics in column filled with 0-20 cm profile soil was 2 times higher than that with 40-60 cm profile soil. The concentration of sulfa antibiotics in the leachate was higher, while the residual concentration in the soil column was lower under a higher leaching velocity. The concentration of sulfa antibiotics in the leachate was close to 500 microg.L-1 when the leaching velocity was 2 mL.min-1, while the concentration of sulfa antibiotics in the leachate was between 100-200 microg.L-1 when the leaching velocity was 1 and 1.5 mL.min-1. The concentrations of sulfa antibiotics in the leachate and soil column increased as the concentration of leaching solution increased. The concentration of sulfa antibiotics in the leachate was close to 0 microg.L-1 when the concentration of leaching solution was 250 microg.L-1 and 125 microg.L-1. When the concentration of leaching solution was 500 microg.L-1, the concentration of sulfa antibiotics in the leachate was close to 500 microg.L-1 and the residue concentration in the soil column was 2 to 3 times higher than that with lower concentration of leaching solution. The results in this research may provide a scientific basis for water irrigation with anibiotics.

[Distribution characteristics and ecological risk of Pb in soils at a lead battery plant].

Soil samples were collected from 18 sites at a relocated lead accumulator factory in the Southwest region, China. Among the 15 sample sites, profile soil samples at 0-20 cm, 20-40 cm and 40-60 cm were taken. Soil lead contents were analyzed by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Characteristics of Pb in topsoil and soil profiles collected from different sampling sites were discussed. Results showed that: (1) The total Pb contents in topsoil (0-20 cm) ranged from 18.18 to 52,332.50 mg x kg(-1). The maximum content greatly exceeded the national standard (HJ 350-2007). The Pb concentration in different workshops followed a decreasing order: the fourth workshop > the second workshop > waste lead storage pit > sewage works > the third workshop > the fifth workshop > the first workshop > the original fourth workshop > the packing workshop > the office area. (2) Results of profile distribution showed that soil depth had no significant effect on Pb content. Lead can be highly accumulated at different depths of the soil, which was quite different from natural soils. (3) Hakanson's potential ecological risk index evaluation showed that there was widespread ecological risk in the soil of the plant, and serious ecological risk existed in some workshops where a large number of lead was enriched. Therefore, the site must be restored in order to reuse it.

[Spectrum study on highly saturated blue organic top-emitting devices with microcavity structure].

The blue top-emitting organic light-emitting devices with cavity effect have been fabricated. The authors used the TBADN : 3% DSAPh as emitting material of blue microcavity OLEDs. The devices consisted of Ag/ITO/CuPc/NPB/TBADN : 3% DSAPh/Alq3/LiF/Al(Ag) structure. On a patterned glass substrate, silver was deposited as reflective anode, and copper phthalocyanine (CuPc) layer as HIL and 4'-bis[N-(1-Naphthyl)-N-phenyl-amino] biphenyl (NPB) layer as HTL were made. Aluminum and silver thin films were made as semi-transparent cathode. The transmittance of aluminum and silver (Al/Ag) cathode was about 30%. In EL spectrum, the full width at half maximum (FWHM) was only 17 nm. By changing the thicknesses of ITO, highly saturated color with Commission Internationale de L'Eclairage chromaticity coordinates (CIEx,y) of (0.141, 0.049) was obtained. In the present article, the emission intensity of spectrum was studied. An appropriate cathode transmittance will result in maximal emission intensity. By using the formula of microcavity, the approximative curve that describes the change of emission intensity with cathode transmittance (or reflectance) was figured out.