Satisfactory Tensile Strength and Strain of Recyclable Polyurethane with a Trimaleimide Structure for Thermal Self-Healing and Anticorrosive Coatings.

Bismaleimide (BMI) is often used as the cross-linking reagent in Diels-Alder (D-A)-type intrinsic self-healing materials (DISMs) to promote the connectivity of damaged surfaces based on reversible D-A bond formation on the molecular scale. Until now, although DISMs have exhibited great potential in the applications of various sensors, electronic skin, and artificial muscles, it is still difficult to prepare DISMs with satisfactory self-healing abilities and high tensile strengths and strains at the same time, thus largely limiting their applications in self-healing anticorrosive coatings. Herein, symmetrical trimaleimide (TMI) was successfully synthesized, and trimaleimide-structured D-A self-healing polyurethane (TMI-DA-PU) was prepared via the reversible D-A reaction (cycloaddition of furan and maleimide). As a DISM, TMI-DA-PU exhibits apparently higher self-healing efficiency (98.7%), tensile strength (25.4 MPa), and strain (1378%) compared to bismaleimide-structured D-A self-healing polyurethane (BMI-DA-PU) (self-healing efficiency, 90.2%; tensile strength, 19.3 MPa; strain, 1174%). In addition, TMI-DA-PU shows a high recycling efficiency (>95%) after 4 cycles of recycling. A series of characterizations indicate that TMI provides more monoene rings as the self-healing sites, forms denser cross-linked structures compared to BMI, and is, thus, more appropriate to be used for DISM applications. Moreover, the barrier abilities of coatings can be semi-quantitatively expressed by the impedance value at 0.01 Hz (|Z|0.01 Hz). The |Z|0.01 Hz value of the TMI-DA-PU coating is 3.93 × 109 Ω cm2 on day 0, which is significantly higher than that of the BMI-DA-PU coating (6.76 × 108 Ω cm2 on day 0), indicating that the denser rigid cross-linked structure of TMI results in the small porosity in the TMI-DA-PU coating, thus effectively improving the anticorrosion performance. The construction of DISMs with the structure of TMI demonstrates immense potential in self-healing anticorrosive coatings.

Genome-wide identification and analysis of ascorbate peroxidase (APX) gene family in hemp (Cannabis sativa L.) under various abiotic stresses.

Ascorbate peroxidase (APX) plays a critical role in molecular mechanisms such as plant development and defense against abiotic stresses. As an important economic crop, hemp (Cannabis sativa L.) is vulnerable to adverse environmental conditions, such as drought, cold, salt, and oxidative stress, which lead to a decline in yield and quality. Although APX genes have been characterized in a variety of plants, members of the APX gene family in hemp have not been completely identified. In this study, we (1) identified eight members of the CsAPX gene family in hemp and mapped their locations on the chromosomes using bioinformatics analysis; (2) examined the physicochemical characteristics of the proteins encoded by these CsAPX gene family members; (3) investigated their intraspecific collinearity, gene structure, conserved domains, conserved motifs, and cis-acting elements; (4) constructed a phylogenetic tree and analyzed interspecific collinearity; and (5) ascertained expression differences in leaf tissue subjected to cold, drought, salt, and oxidative stresses using quantitative real-time-PCR (qRT-PCR). Under all four stresses, CsAPX6, CsAPX7, and CsAPX8 consistently exhibited significant upregulation, whereas CsAPX2 displayed notably higher expression levels under drought stress than under the other stresses. Taken together, the results of this study provide basic genomic information on the expression of the APX gene family and pave the way for studying the role of APX genes in abiotic stress.

ε-Polylysine organic ultra-long room-temperature phosphorescent materials based on phosphorescent molecule doping.

Achieving long-lived room-temperature phosphorescence from pure organic amorphous polymers is attractive, and afterglow materials with colour-tunable and multiple-stimuli-responsive afterglow are particularly important, but only few materials with these characteristics have been reported so far. Herein, a facile and general method is reported to construct a series of ε-polylysine (ε-PL)-based afterglow materials with tunable colour (from blue to red) and long life. By doping guest molecules into ε-PL to obtain composite materials, the polymer matrix provides a rigid environment for luminescent groups, resulting in amorphous polymers with different RTPs. In this system, the materials even have impressive humidity-stimulated responses, and the phosphorescence emission exhibits excitation-dependent and time-dependent properties. The humidity-responsive afterglow is caused by the destruction of hydrogen bonds and quenching of triplet excitons. The time-dependent afterglow should stem from the formation of diversified RTP emissive species with comparable but different lifetimes. 9,10-diaminophene has Ex-De properties in the film doping state. With the change of excitation wavelength (254 nm to 365 nm), the emission wavelength shifts from 461 nm to 530 nm, accompanied by the change of emission colour from blue to green. In addition, the phosphorescence life of the film is the longest, up to 2504.7 ms, and the afterglow lasts up to 15 s, which is conducive to its applications in anti-counterfeiting and information encryption.

Environmental Benefit Assessment of Second-Life Use of Electric Vehicle Lithium-Ion Batteries in Multiple Scenarios Considering Performance Degradation and Economic Value.

Second-life use of electric vehicle lithium-ion batteries (LIBs) is an inevitable trend; however, battery performance degradation increases environmental loads. This study evaluated the life cycle environmental impacts of second-life use of LIBs in multiple scenarios, considering performance degradation and economic value. The results showed that a component replacement rate of retired LIBs below 50% made the batteries worthy of repurposing. Reusing whole packs of retired LIBs was better than using only cells or modules owing to the environmental loads from diagnosis, disassembly, replacement, and test processes. The battery energy density and performance degradation significantly affect the maximum return on the environmental input. Compared with lithium iron phosphate (LFP) batteries, new lithium nickel manganese cobalt oxide (NMC) batteries, or lead-acid batteries, using retired NMC-811 batteries with capacities as low as 60.7% for energy storage systems to store wind electricity rather than hybrid or photovoltaic electricity, had substantial environmental benefits, including a low global warming potential. Considering the costs of battery recycling, labor, and electricity, using whole packs of retired LIBs could simultaneously achieve high economic and environmental values in energy storage and peak shaving scenarios.

Bioleaching of indium from waste LCD panels by Aspergillus niger: Method optimization and mechanism analysis.

Using Aspergillus niger (A. niger) to produce low-concentration organic acids is challenging for dissolving In3O2 from waste LCD (liquid crystal display) panels with high toxicity. In this study, three bioleaching approaches from the general and the optimized fermentation systems were investigated respectively to compare indium recovery effects and firstly clarified its bioleaching mechanism. The indium bioleaching efficiency can be improved from 12.3% to 100% by fermentation method optimization. Carboxy groups from organic acids and proteins were the critical substances to release H+ for leaching indium mainly competed with iron via reactions analysis. The effective components increased after optimizing, including the dissociative H+ concentration, the effective carboxyl groups for leaching metal oxides, and the output of oxalic acid. A. niger biomass prevented the contact between H+ and In3O2 and adsorbed In3+ adverse to indium recovery. The bioleaching effects of fermentation broth for indium can be further promoted by controlling bioleaching process parameters.

Ecotoxicity monitoring and bioindicator screening of oil-contaminated soil during bioremediation.

A series of toxicity bioassays was conducted to monitor the ecotoxicity of soils in the different phases of bioremediation. Artificially oil-contaminated soil was inoculated with a petroleum hydrocarbon-degrading bacterial consortium containing Burkholderia cepacia GS3C, Sphingomonas GY2B and Pandoraea pnomenusa GP3B strains adapted to crude oil. Soil ecotoxicity in different phases of bioremediation was examined by monitoring total petroleum hydrocarbons, soil enzyme activities, phytotoxicity (inhibition of seed germination and plant growth), malonaldehyde content, superoxide dismutase activity and bacterial luminescence. Although the total petroleum hydrocarbon (TPH) concentration in soil was reduced by 64.4%, forty days after bioremediation, the phytotoxicity and Photobacterium phosphoreum ecotoxicity test results indicated an initial increase in ecotoxicity, suggesting the formation of intermediate metabolites characterized by high toxicity and low bioavailability during bioremediation. The ecotoxicity values are a more valid indicator for evaluating the effectiveness of bioremediation techniques compared with only using the total petroleum hydrocarbon concentrations. Among all of the potential indicators that could be used to evaluate the effectiveness of bioremediation techniques, soil enzyme activities, phytotoxicity (inhibition of plant height, shoot weight and root fresh weight), malonaldehyde content, superoxide dismutase activity and luminescence of P. phosphoreum were the most sensitive.