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Nanosized titanium oxide (TiO2) material is a promising photocatalyst for the degradation of organic pollutants, whereas the difficulty of its recycling hinders its practical application. Herein, we reported the preparation of a novel titanium oxide/polysulfone (TiNPs/PSF) composite hollow microspheres by the combination of Pickering emulsification and the solvent evaporation technique and their application for the photodegradation of methyl blue (MB). P25 TiO2 nanoparticles dispersed on the surface of PSF microspheres. The porosity, density and photoactivity of the TiNPs/PSF composite microsphere are influenced by the TiO2 loading amount. The composite microsphere showed good methyl blue (MB) removal ability. Compared with TiO2 P25, and PSF, a much higher MB adsorption speed was observed for TiNPs/PSF microspheres benefited from their porous structure and the electrostatic attractions between the MB+ and the negatively charged PSF materials, and showed good degradation efficiency. For TiNPs/PSF composite microsphere with density close to 1, a 100% MB removal (10 mg L−1) within 120 min at a catalyst loading of 2.5 g L−1 can be obtained under both stirring and static condition, due to well dispersing of TiO2 particles on the microsphere surface and its stable suspending in water. For the non-suspended TiNPs/PSF composite microsphere with density bigger than 1, the 100% MB removal can be only obtained under stirring condition. The removal efficiency of MB for the composite microspheres retained 96.5%, even after 20 cycles. Moreover, this composite microsphere also showed high MB removal ability at acidic condition. The high catalysis efficiency, excellent reusability and good stability make this kind of TiNPs/PSF composite microsphere a promising photocatalyst for the water organic pollution treatment. [ABSTRACT FROM AUTHOR]

As the continuous development of aerospace and outer space exploration, high-performance thermal insulation materials with high-temperature resistance and attractive mechanical properties have always been a fascinating topic of research to protect human body or components from extreme environments. In this research, hydrophobic silicon dioxide (SiO2) nanoparticles as molecular skeleton enhancers and heat transfer inhibitors are introduced in crosslinked polyimide (PI) aerogels with rigid molecular structure to maintain the stable nanoporous network structure. The density, shrinkage, porosity, specific surface area and pore size distribution of PI/SiO2 composite aerogels can be adjusted by the addition of SiO2 nanoparticles, so as to improve the comprehensive performances. The excellent thermal stability and mechanical properties of PI/SiO2 composite aerogels with super-high working temperature of over 550 °C and high modulus of compression and tension (compression Young’s modulus of 37.75 MPa and tensile modulus of 237.1 MPa) ensure their use as a structural component. The charming thermal conductivity (29.7 mWm−1 K−1) and excellent flame resistance make them a candidate for high-performance thermal insulation materials.Graphical abstract: As the continuous development of aerospace and outer space exploration, high-performance thermal insulation materials with high-temperature resistance and attractive mechanical properties have always been a fascinating topic of research to protect human body or components from extreme environments. In this research, hydrophobic silicon dioxide (SiO2) nanoparticles as molecular skeleton enhancers and heat transfer inhibitors are introduced in crosslinked polyimide (PI) aerogels with rigid molecular structure to maintain the stable nanoporous network structure. The density, shrinkage, porosity, specific surface area and pore size distribution of PI/SiO2 composite aerogels can be adjusted by the addition of SiO2 nanoparticles, so as to improve the comprehensive performances. The excellent thermal stability and mechanical properties of PI/SiO2 composite aerogels with super-high working temperature of over 550 °C and high modulus of compression and tension (compression Young’s modulus of 37.75 MPa and tensile modulus of 237.1 MPa) ensure their use as a structural component. The charming thermal conductivity (29.7 mWm−1 K−1) and excellent flame resistance make them a candidate for high-performance thermal insulation materials. [ABSTRACT FROM AUTHOR]

Saline and alkaline stresses limit plant growth and reduce crop yield. Soil salinization and alkalization seriously threaten the sustainable development of agriculture and the virtuous cycle of ecology. Biofertilizers made from plant growth-promoting rhizobacteria (PGPR) not only enhance plant growth and stress tolerance, but also are environmentally friendly and cost-effective. There have been many studies on the mechanisms underlying PGPRs enhancing plant salt resistance. However, there is limited knowledge about the interaction between PGPR and plants under alkaline-sodic stress. To clarify the mechanisms underlying PGPR's improvement of plants' tolerance to alkaline-sodic stress, we screened PGPR from the rhizosphere microorganisms of local plants growing in alkaline-sodic land and selected an efficient strain, Bacillus altitudinis AD13-4, as the research object. Our results indicate that the strain AD13-4 can produce various growth-promoting substances to regulate plant endogenous hormone levels, cell division and differentiation, photosynthesis, antioxidant capacity, etc. Transcriptome analysis revealed that the strain AD13-4 significantly affected metabolism and secondary metabolism, signal transduction, photosynthesis, redox processes, and plant-pathogen interactions. Under alkaline-sodic conditions, inoculation of the strain AD13-4 significantly improved plant biomass and the contents of metabolites (e.g., soluble proteins and sugars) as well as secondary metabolites (e.g., phenols, flavonoids, and terpenoids). The 16S rRNA gene sequencing results indicated that the strain AD13-4 significantly affected the abundance and composition of the rhizospheric microbiota and improved soil activities and physiochemical properties. Our study provides theoretical support for the optimization of saline-alkali-tolerant PGPR and valuable information for elucidating the mechanism of plant alkaline-sodic tolerance.

SYP71, a plant-specific Qc-SNARE with multiple subcellular localization, is essential for symbiotic nitrogen fixation in nodules in Lotus , and is implicated in plant resistance to pathogenesis in rice, wheat and soybean. Arabidopsis SYP71 is proposed to participate in multiple membrane fusion steps during secretion. To date, the molecular mechanism underlying SYP71 regulation on plant development remains elusive. In this study, we clarified that AtSYP71 is essential for plant development and stress response, using techniques of cell biology, molecular biology, biochemistry, genetics, and transcriptomics. AtSYP71 -knockout mutant atsyp71-1 was lethal at early development stage due to the failure of root elongation and albinism of the leaves. AtSYP71 -knockdown mutants, atsyp71-2 and atsyp71-3 , had short roots, delayed early development, and altered stress response. The cell wall structure and components changed significantly in atsyp71-2 due to disrupted cell wall biosynthesis and dynamics. Reactive oxygen species homeostasis and pH homeostasis were also collapsed in atsyp71-2 . All these defects were likely resulted from blocked secretion pathway in the mutants. Strikingly, change of pH value significantly affected ROS homeostasis in atsyp71-2 , suggesting interconnection between ROS and pH homeostasis. Furthermore, we identified AtSYP71 partners and propose that AtSYP71 forms distinct SNARE complexes to mediate multiple membrane fusion steps in secretory pathway. Our findings suggest that AtSYP71 plays an essential role in plant development and stress response via regulating pH homeostasis through secretory pathway., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhang, Zhou, Kou, Liu, Zhao, Qin, Wang, Qian, Li, Huang, Wang, Zhao, Li, Wu, Jiang, Feng, Zhu and Li.)

Nanosized titanium oxide (TiO 2 )-based photocatalysts have exhibited great potential for the degradation of organic contaminants, while their weak absorption of visible light limits the photocatalytic efficiency. Herein, a novel reduced graphene oxide/TiO 2 -polyphenylenesulfone (rGO/TiO 2 -PPSU) hybrid ultrafiltration membrane has been successfully prepared via a non-solvent induced phase-separation method, in which the synergistic coupling between the rGO and TiO 2 could endowed the fabricated membranes with visible-light-driven efficient photocatalytically degradation of organic pollutants and outstanding photocatalytic and antifouling properties. Compared with the PPSU membranes prepared with Graphene oxide and TiO 2 , respectively, the rGO/TiO 2 -PPSU membrane demonstrated significant photodegradation towards phenazopyridine hydrochloride (PhP) solution under ultraviolet light (improved about 71 and 43%) and visible light (improved about 153 and 103%). The permeability and flux recovery rates of the membrane indicated that the high flux of the rGO/TiO 2 -PPSU membrane can be greatly restored after fouling, due to the improved self-cleaning properties under visible light static irradiation. With the properties of high performance of photocatalytic degradation and good self-cleaning ability, the rGO/TiO 2 -PPSU membrane would have great potential in water treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Dai, Zhang, Wang, Chen, Chen, Qian and Yu.)

A novel diamine named (2,2'-bibenzoxazole)-5,5'-diamine (DBOA) and derived polyimides (PIs) were successfully synthesized. The rigid, linear, symmetrical molecular structure and the strong charge transfer complex (CTC) were considered to be the reasons for the improved molecular packing and enhanced thermal properties of the polymers. These DBOA based PIs exhibited a higher glass transition temperature ( T g ) and lower coefficient of thermal expansion (CTE) than traditional benzoxazole (BOA) based PIs. Meanwhile, the PI derived from DBOA and BPDA (3,3',4,4'-biphenyltetracarboxylic dianhydride) exhibited high T g (395 °C) and low CTE (8.9 ppm per °C), and is expected to be applied in organic light-emitting diode (OLED) displays., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

5-Amine-2-(4-amino-benzene)-1-phenyl-benzimidazole ( N -PhPABZ) was successfully synthesized and polymerized with 3,3',4,4'-biphenyl tetracarboxylic dianhydride (BPDA) to obtain a novel N -phenyl-poly(benzimidazole imide) ( N -Ph-PBII). The successful incorporation of N -phenyl addressed the issue of high H 2 O-absorption of traditional PBIIs while retained the superheat resistance property. The resulting N -Ph-PBII possessed a high glass-transition temperature ( T g ) up to 425 °C and a low affinity for water of 1.4%. Furthermore, the loose molecular packing and noncoplanar structures led to an increase in optical transparency for the modified PBII., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)