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Very recently, the poor contact between the perovskite and carrier selective layer has been regarded as a critical issue for improving the performance and stability of perovskite solar cells (PSCs). In this study, the buried interface of regularly structured PSCs has been targeted. Glutathione-coated gold nanoparticles (GSH-AuNPs) are used as double-sided passivating agents to improve the quality of the perovskite films. It has been demonstrated that the GSH-AuNPs interact strongly with the SnO2 underlayer and the upper perovskite layer, significantly reducing the defect densities of this interface. Thus, the power conversion efficiency (PCE) of the PSCs can be increased from 20.46% (control, 19.38%, IPCE corrected) to 22.22% (GSH-AuNPs modified, 21.10%, IPCE corrected) with notable enhancement in Voc and FF. Moreover, the strong interaction between the C═O groups of GSH-AuNPs and the undercoordinated Pb2+ species of the perovskite films inhibits the formation of metallic Pb0. As a result, the unencapsulated GSH-AuNPs-modified devices retained 80% of their initial PCEs after 1000 h at ambient conditions, with a relative humidity (RH) of 60 ± 5%. UV-resistant PSCs have also been demonstrated after introducing GSH-AuNPs. Therefore, our findings demonstrate the bidirectional therapy strategy as a feasible approach for achieving efficient and UV-resistant PSCs.

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The literature on polyvinyl alcohol (PVA) films is extensive, however, these methods often necessitate intricate synthesis processes or the addition of plasticizers to modify the strength and water solubility of the PVA material. A high-strength UV radiation-resistant composite film by chelating Fe3+ with lignin and PVA, which exhibits excellent hydrolysis resistance is developed. This composite film is prepared simply by incorporating a small amount of dealkalized lignin (APPL) and ferric chloride (FeCl3) into PVA through a straightforward composite process. During the scanning test, it is noted that the film exhibits a high density of uniformly dispersed particles, endowing it with efficient ultraviolet absorption capabilities. The infrared and anti-dissolution tests reveal that the coordination of Fe3+ with lignin imparts an outstanding hydrolysis resistance to the film, obviating the need for any extender, curing agent, acid or base. The tensile fracture strength reaches an impressive 187.81Mpa in the tensile test. UV and indicator card tests unequivocally demonstrate that the film achieves a remarkable 100% anti-UV efficiency. This Fe3+ chelated lignin/PVA composite film, with its facile preparation, environmental sustainability, high strength, and outstanding anti-ultraviolet efficiency, can be deployed across diverse applications requiring robust protection against ultraviolet radiation.

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Bio-based food packaging materials have elicited growing interests due to their great degradability, high safety and active biofunctions. In this work, by simultaneously introducing the polyphenolic extracts from Capsicum annuum leaves and ferric ion (Fe3+) into the Polyvinyl alcohol/kappa-carrageenan (PVA/κ-carrageenan)-based film-forming matrix, an active package film was developed, with the purpose to improve the food shelf life. The experimental results indicated that the existence of Fe3+ can not only improve the mechanical properties owing to the multiple dynamic coordinated interactions, but also endow the composite films with excellent fire-retardancy. Moreover, the composite films could display excellent UV resistant performance, water vapor/oxygen gas barrier properties and antioxidant activities with the corporation of polyphenols. In particular, the highest DPPH and ABTS radical scavenging capacities for composite film (PC-PLP7 sample) were evaluated to be 82.5 % and 91.1 %, respectively. Higher polyphenol concentration is favorable to the bio-functions of the materials. Benefitting from these features, this novel kind of films with a dense and steady micro-structure could be further applicated in fruit preservations, where the ripening bananas were ensured with the high storage quality. This integration as a prospective food packaging material provides an economic and eco-friendly approach to excavate the high added-values of biomass.

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A bacterium, designated strain ZK17L-C2T, was isolated from the leaf tissues of wheat (Triticum aestivum) collected in Chengdu, Sichuan Province, PR China. It is aerobic, non-motile, Gram-negative, rod-shaped and red-to-pink in colour. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZK17L-C2T belonged to the genus Hymenobacter and was most closely related to Hymenobacter rigui KCTC 12533T (98.68 %) and Hymenobacter metallilatus 9PBR-2T (98.19 %). Digital DNA-DNA hybridization (dDDH) values between strain ZK17L-C2T and these two type strains were 26.6 and 26.5 %, and average nucleotide identity (ANI) values were 84.9 and 84.8 %, respectively; these values are lower than the proposed and generally accepted species boundaries for dDDH and ANI. The genomic DNA G+C content of strain ZK17L-C2T was 59.4 mol%. It can grow at pH 5.5-7.5 and 15-30 °C, which is different from the closely related type strains. The major fatty acids of strain ZK17L-C2T were iso-C15 : 0, C16 : 0 and C18 : 0. Overall, the results from biochemical, chemical taxonomy and phylogenetic analyses indicate that strain ZK17L-C2T (=CGMCC 1.19373T=KCTC 92184 T) represents a new species of the genus Hymenobacter, for which the name Hymenobacter endophyticus sp. nov. is proposed.

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The destruction of polymers under the influence of ultraviolet (UV) radiation is the cause of their aging and deterioration of strength properties. Asphaltenes are low-value waste products after the refining and deasphalting of heavy crude oil, which absorb UV radiation well. Asphaltenes require rational utilization, which suggests their use as UV stabilizing agents for polymers. In this work, asphaltenes were used to prevent UV aging of polypropylene (PP) by adding them in a mass fraction from 5% to 30% within an asphaltene/PP composite material. Rheometry, calorimetry, X-ray diffraction analysis, and tensile strength of PP films containing asphaltenes were performed before and after their intense UV irradiation for accelerated aging. Asphaltenes slightly reduce the viscosity, crystallinity, and mechanical strength of the initial PP due to their plasticizing effect. However, this deterioration in properties is more than compensated when studying UV-aged samples. Intense UV aging causes multiple catastrophic drops in the viscosity and strength of pure PP with the preservation of crystallinity due to the break of polymer chains and a decrease in molecular weight by approximately eight times. Asphaltenes suppress the destruction of PP, which is expressed in a significantly smaller decline in its viscosity and strength due to UV aging. The most optimal content of asphaltenes is 20%, which suppresses UV destruction by six times and best preserves the strength properties of PP.

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Preparing UV-resistant heterogeneous wettability patterns is critical for the practical application of surfaces with heterogeneous wettability. However, combining UV-resistant superhydrophobic and superhydrophilic materials on heterogeneous surfaces is challenging. Inspired by the structure of cell membranes, a UV-resistant heterogeneous wettability-patterned surface (UPS) is designed via laser ablation of the coating of multilayer structures. UV-resistant superhydrophobic silica patterns can be created in situ on surfaces covered with superhydrophilic TiO2 nanoparticles. The UV resistance time of the UPS with a TiO2 -based surface is more than two orders of magnitude higher than that obtained with other surface molecular modification methods that require a mask. The cell-membrane-like structure of the UPS regulates the migration of internal siloxane chain segments in the hydrophilic and hydrophobic regions of the surface. The UPS enables efficient patterning of functional materials under UV irradiation, controlling the wetting behavior of liquids in open-air systems. Furthermore, its heterogeneous wettability remains stable even after 50 h of intense UV irradiation (365 nm, 500 mW cm-2 ). These UV-resistant heterogeneous wettability patterned surfaces will likely be applied in microfluidics, cell culture, energy conversion, and water collection in the future.

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Personal protective textiles have attracted extensive interest since Corona Virus Disease 2019 has broken out. Moreover, developing eco-friendly, multifunctional waterproof, and breathable surface is of great importance but still faces enormous challenges. Notably, good hydrophobicity and breathability are necessary for protective textiles, especially protective clothing and face masks for healthcare. Herein, the multifunctional composite coatings with good UV-resistant, anti-oxidative, hydrophobic, breathable, and photothermal performance has been rapidly created to meet protective requirements. First, the gallic acid and chitosan polymer was coated onto the cotton fabric surface. Subsequently, the modified silica sol was anchored on the coated cotton fabric surface. The successful fabrication of composite coatings was verified by RGB values obtained from the smartphone and K/S value. The present work is an advance for realizing textile hydrophobicity by utilizing fluorine-free materials, compared with the surface hydrophobicity fabricated with conventional fluorinated materials. The surface free energy has been reduced from 84.2 to27.6 mJ/m2 so that the modified cotton fabric could repel the ethylene glycol, hydrochloric acid, and sodium hydroxide solutions, respectively. Besides, the composite coatings possesses lower adhesion to deionized water. After 70 cycles of the sandpaper abrasion, the fluorine-free hydrophobic coatings still exhibits good hydrophobicity with WCA of 124.6 ± 0.9°, with overcoming the intrinsic drawback of the poor abrasion resistance of hydrophobic surfaces. Briefly, the present work may provide a universal strategy for rapidly creating advanced protective coatings to meet personal healthcare, and a novel method for detecting RGB values of composite coatings by smartphone.

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Lignin is an indispensable and essential compound present in plants. It is a renewable resource and a green alternative to traditional petroleum energy. The rational utilization of lignin can reduce the environmental damage caused by traditional industrial development. The preparation of lignin nanoparticles (LNPs) using the self-assembly method is one of the most favorable ways to achieve high value-added utilization of lignin. However, the process requires an in-depth understanding of the sphere-forming mechanism of lignin self-assembly and the interaction of self-assembly forces. We used the same raw materials and two different preparation methods to prepare LNPs. The results revealed that the variation in the order of the dropwise addition of lignin solution and deionized water produced LNPs with varying average sizes. The sphere-forming mechanisms of the two kinds of lignin nanoparticles were discussed for the preparation of UV-resistant polyvinyl alcohol (PVA) polymeric films. During lignin spherification, the faster the solution reaches the supersaturation state, the faster the spherogenesis rate is, the smaller the size is, and the narrower the particle size distribution is. The lignin micro/nanospheres are produced by exploiting the π-π bonding interactions in lignin itself. The lignin micro/nanospheres are then mixed with PVA to form a film to obtain a lignin-PVA composite film material with an anti-UV effect.

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Oil separation is crucial for avoiding environmental pollution originating from industrial wastewater and oil spillage; therefore, it is essential to develop techniques for oil separation. Herein, a new membrane with superhydrophilicity was synthesized by a facile, green, and low-cost method. First, cellulose non-woven fabric (CNWF) was modified by poly (catechin) (pCA), which has good antioxidant and antibacterial activities, to make it unaffected by ultraviolet light and to improve the stability of the structure. Then, hydrolyzed polydimethylsiloxane (PDMS) was coated on the pCA@CNWF surface via chemical bonding to make the composite hydrophobic. This durable superhydrophobic fabric can be used to separate various oil/water mixtures by gravity-driven forces with high separation efficiency (over 98.9%). Additionally, the PDMS-pCA@CNWF possesses the advantages of flexibility, high efficiency, and an outstanding self-cleaning performance, and demonstrates significant potential for applications in various environments, even under various harsh conditions, which make it very promising for the treatment of oil pollution in practical applications.

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Acanthopanax senticosus has been used to extract active products. However, abundant Acanthopanax senticosus residues (ASR), which contain plenty of lignin are discarded after extraction. An appropriate extraction method should be chosen to obtain the lignin with such desirable properties. Thus, this study investigated the effect of alkali, milled wood, deep eutectic solvent and ethanol methods on the lignin. Lignin obtained from different extraction methods were characterized, yields, chemical structure, thermal behavior, molecular weight and phenolic content were evaluated. The results show that the process of lignin acquisition has a great influence on the properties of lignin. Moreover, the multifarious functional groups exist in lignin macromolecules, such as phenolic, ether groups and other chromophores, conferred good UV resistance to lignin. Among them, the lignin from alkali method has the most phenolic-OH groups and smallest molecular weight result in a good UV-resistant, the SPF value achieves 2.39 at 1% AL content, the alkali method was the best way to make sunscreen blended with cream take various factors into consideration. This study used lignin as a bioactive ingredient to provide UV-resistant property to sunscreen formulations. Furthermore, lignin extracted from Acanthopanax senticosus residue provides a new application for the treatment of herb residue waste.

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The commercial flame retardant is an emerging contaminant (EC) commonly found in soils and sediments. A coupled UV-photolysis-biodegradation process was used to decompose decabromodiphenyl ether (BDE-209) in clay slurries. A novel bioslurry bioreactor (NBB) was employed in which BDE-209 degradation was maximized by the simultaneous application of LED UVA irradiation and biodegradation by a mixed bacterial culture. The rate of BDE-209 degradation decreased in the order: coupled UV photolysis-biodegradation (1.31 × 10-2 day-1) > UV photolysis alone (1.10 × 10-2 day-1) > biodegradation alone (1.00 × 10-2 day-1). Degradation intermediates detected included hydroxylated polybrominated diphenylethers, partially debrominated PBDE congeners and polybrominated dibenzofuran. The UV-resistant bacterial strains isolated that could utilize BDE-209 as a sole carbon source included Stenotrophomonas sp., Pseudomonas sp., and Microbacterium sp. These strains encoded important functional genes such as dioxygenase and reductive dehalogenases. Continuous UV irradiation during the NBB process affected various biochemical oxidative reactions during PBDEs biodegradation. Simultaneous photolysis and biodegradation in the NBB system described reduces operational time, energy, expense, and maintenance-demands required for the remediation of BDE-209 when compared to sequential UV-biodegradation process or to biodegradation alone.

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The carbon soot is formed as a consequence of incomplete combustion of hydrocarbons and organic matter. It causes respiratory diseases like lung cancer and asthma and contributes to 1.6 million premature deaths every year. The primary source of soot is the vehicular emissions which can be controlled using a simple device retrofitted to the silencer. In the present study, various additives were added to the collected soot, forming a homogenous adhering suspension which can be used as an ink. Tests proved that this ink is safe to use and it also complied with the standards of the Indian Government for fountain pen ink. The ink had excellent water-resistant properties as a result of its Rf (retention factor) value was found to be 0.0133. When compared with conventional black inks, the ink dries quickly, and on varying the temperature of the surroundings from - 30 to 50 °C, the ink remained in the writable viscosity range of 4.6 to 4.9 mPa s, thus making it universally malleable. The ink also proved to be UV resistant and neither exhibited feathering, show-through, bleeding nor shading. The ink is versatile; it can be used for a wide range of applications including writing, painting, and spraying.

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A Gram-stain-positive, aerobic, rod-shaped, non-motile, endospore-forming and UV-resistant bacterial strain, designated strain TKL69T, was isolated from sandy soil sampled in the Taklimakan Desert. The strain grew at 20-50 °C, pH 6-9 and with 0-12 % (w/v) NaCl. The major fatty acids were anteiso-C15 : 0, iso-C15 : 0 and C16 : 0. The only respiratory quinone was MK-7. The cell-wall peptidoglycan was meso-diaminopimelic acid. Diphosphatidyl glycerol, two unidentified aminophospholipids and one unidentified phospholipid were identified as the major polar lipids. Genomic DNA analysis revealed a G+C content of 38.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain TKL69T has the highest similarity to Salinibacillus xinjiangensis CGMCC 1.12331T (96.9 %) but belongs to an independent taxon separated from other genera of the family Bacillaceae. Phylogenetic, phenotypic and chemotaxonomic analyses suggested that strain TKL69T represents a novel species of a new genus, for which the name Radiobacillus gen. nov., sp. nov. is proposed, with the type strain being Radiobacillus deserti TKL69T (=JCM 33497T=CICC 24779T).

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There is a growing interest in window air filters to protect indoor air quality from ultrafine particulate matter (PM) in outdoor air. The filters for this purpose must achieve high filtering efficiency without compromising the original functions of the window, such as high air permeability and visibility. Several filters meeting these requirements have been developed and demonstrate a high PM2.5 filtering efficiency. However, these filters are installed outside the window or on the window screen guard, thereby requiring high levels of ultraviolet (UV), chemical, and thermal resistance. These requirements have been overlooked so far. In this study, we examine the fabrication and performance of a polybenzimidazole-benzophenone (PBI-BP) composite nanofiber air filter that demonstrates superb UV resistance and chemical and thermal durability. Because of the UV absorbance of the BP in the nanofibers, the filter membrane is robust even under prolonged UV exposure, which is essential for filters for this purpose. The filter membrane is not damaged even after treatment in strong acids or annealing at high temperature up to 400 °C. Thus, the PBI-BP composite filter is suitable for practical application in window air filters and can be adapted to develop filters used under other harsh environments.

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Directly writing 3D structures into supporting mediums is a relatively new developing technology in additive manufacturing. In this work, durable and recyclable liquid-like solid (LLS) materials are developed as supporting mediums that are stable for both UV and thermal solidification. Our LLS material is comprised of densely packed oil droplets in a continuous aqueous medium, known as emulsion glass. Its elastic nature emerges from the jammed structure of oil droplets, which offers this LLS material rapidly self-healing ability. Moreover, the yield stress of the glass is relatively low and can be tuned by the viscosity and weight percentage of oil. The capability of the emulsion glass as supporting mediums is successfully demonstrated by directly writing and then curing designed structures. The emulsion glass has been repeatedly used at least 6 times upon exposure to UV irradiation and heat, implying it can expand the applications of supporting medium to the writing process involving UV- and thermal-curable inks simultaneously.

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The hydrophobicity and color stability of wood are important properties that can be easily changed when wood is used as a raw material for outdoor products, reducing the service life of wood. Herein, an epoxy@ZnO coating was applied by a two-step simple spray coating method to improve the hydrophobicity and color stability of Styrax tonkinensis wood. The hydrophobicity, robustness of coating, as well as the color stability of uncoated wood samples and epoxy@ZnO coated wood samples were evaluated. The microstructure morphology and crystal structures of the coating were also characterized by a field-emission scanning electron microscope (FESEM) and X-ray diffraction (XRD) analysis, respectively. Results showed that the obtained epoxy@ZnO coating was not only superhydrophobic with an average water contact angle of 154.1°, but also maintained superhydrophobicity with an average water contact angle of 149.6° after five water jetting tests. The color stability of the coated wood samples was improved by around 50% compared to that of uncoated wood samples. Additionally, a continuous epoxy@ZnO coating with hierarchical micro/nanoscale structures constructed by the wurtzite hexagonal structure of ZnO micro/nanoparticles on wood surfaces was confirmed.

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As the most favored high-quality biopolymer, silk fiber is widely used in the textile and medical industries owing to its impressive mechanical properties, wear comfort properties, and biocompatibility. However, its photoinstability, chemical instability, and thermal instability seriously hinder its utilization in luxurious fashionable apparels. Therefore, we herein report the preparation of an ultrathin and uniform TiO2-Al2O3 cloth with a thickness of just six in a thousand of fiber on silkworm silk fiber via atomic layer deposition. In this ultrathin composite cloth, the outer TiO2 layer acts as a sacrificial ultraviolet (UV) absorbent to dissipate large amounts of UV energy. Free radicals and electrons generated by the TiO2 layer are effectively blocked outside the surface of the bulk silk fiber by the inner insulating Al2O3 layer. The excellent UV-resistance of the modified silk fiber was confirmed by a lack of fade in the silk fabric after exposure to UV light for 60 min (equal to continuous exposure to strong sunlight for 3285 days). Compared with silk fiber, the tenacity of the prepared SF-200Al2O3-800TiO2 increased by 18.9% even after sunlight exposure. In addition, both the chemical and thermal stabilities of the modified silk fiber were improved. This technology is expected to have potential applications in various fields, such as high-end fabric development and smart materials, and will further guide material design for future innovations in functional fibers and devices.

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We report here the draft genome sequence of a novel UV-resistant bacterium isolated from dry soil on the south coast of Puerto Rico. Based on polyphasic taxonomy, strain MC1A represents a new species and the name Solirubrum puertoriconensis is proposed. Assembly was performed using NGEN Assembler into eight contigs (N50 = 1,292,788), the largest of which included 1,549,887 bp. The draft genome consists of 4,810,875 bp and has a GC content of 58.7%. Several genes related to DNA repair and UV resistance were found. The Whole Genome Shotgun project is available at DDBJ/EMBL/GenBank under the accession LNAL00000000.

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Recent studies have demonstrated the potential to use Bacillus pumilus endospores as a surrogate for human adenovirus (HAdV) in UV disinfection studies. The use of endospores has been limited by observations of batch-to-batch variation in UV sensitivity. This study reports on a propagation method that utilizes a commercially available medium to produce UV tolerant B. pumilus endospores with a consistent UV sensitivity. It is further demonstrated that the endospores of B. pumilus strain (ATCC 27142), produced using this protocol (half strength Columbia broth, 5 days incubation, with 0.1mM MnSO4), display a UV dose-response that is similar to that of HAdV. Endospore stocks could be stored in ethanol for up to two months at 4 °C without a significant change in UV sensitivity. Synergistic endospore damage was observed by pre-heat treatment of water samples followed by UV irradiation. UV tolerant B. pumilus endospores are a potential surrogate of HAdV for UV treatment performance tests in water utilities which do not have in-house research virology laboratories.

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