Special Structure Research Articles

Characterizing pituitary adenomas in clinical notes: Corpus construction and its application in LLMs.

Objective: Faced with the challenges of differential diagnosis caused by the complex clinical manifestations and high pathological heterogeneity of pituitary adenomas, this study aims to construct a high-quality annotated corpus to characterize pituitary adenomas in clinical notes containing rich diagnosis and treatment information. Methods: A dataset from a pituitary adenomas neurosurgery treatment center of a tertiary first-class hospital in China was retrospectively collected. A semi-automatic corpus construction framework was designed. A total of 2000 documents containing 9430 sentences and 524,232 words were annotated, and the text corpus of pituitary adenomas (TCPA) was constructed and analyzed. Its potential application in large language models (LLMs) was explored through fine-tuning and prompting experiments. Results: TCPA had 4782 medical entities and 28,998 tokens, achieving good quality with the inter-annotator agreement value of 0.862-0.986. The LLMs experiments showed that TCPA can be used to automatically identify clinical information from free texts, and introducing instances with clinical characteristics can effectively reduce the need for training data, thereby reducing labor costs. Conclusion: This study characterized pituitary adenomas in clinical notes, and the proposed method were able to serve as references for relevant research in medical natural language scenarios with highly specialized language structure and terminology.

Study on the foam properties of peanut oil body (POB)-based oil-in-water-in-oil (O/W/O) foamed emulsion gel: The key role played by the interface between the water phase and the outer oil phase

A novel POB-based O/W/O foamed emulsion gel was constructed. The mechanism by which POB strengthens the foamed emulsion gel was preliminarily explored by studying the microstructure and rheological properties, and the applications of POB in decoration and 3D printing were analyzed. The adsorption of POBs and their fragments might strengthen the interface between the water and internal oil phases, thereby increasing the yield stress of the system, which protected the O/W/O structure from being damaged during whipping, and formed a special foam structure where air-in-oil (A/O) structures and O/W/O structure coexist. Besides, adding POB promoted the overrun of the emulsion gel, and the maximum overrun rate was 68.6 %. Finally, POB-based O/W/O foamed emulsion gel exhibited good decoration and 3D printing performance and is expected to become a healthy and higher-quality foamed food in the future.

Relaxed selection in evolution of genes regulating limb development gives clue to variation in forelimb morphology of cetaceans and other mammals.

Cetaceans have evolved unique limb structures, such as flippers, due to genetic changes during their transition to aquatic life. However, the full understanding of the genetic and evolutionary mechanisms behind these changes is still developing. By examining 25 limb-related protein-coding genes across various mammalian species, we compared genetic changes between aquatic mammals, like whales, and other mammals with unique limb structures such as bats, rodents and elephants. Our findings revealed significant modifications in limb-related genes, including variations in the Hox, GDF5 and Evx genes. Notably, a relaxed selection in several key genes was observed, suggesting a lifting of developmental constraints, which might have facilitated the emergence of morphological innovations in cetacean limb morphology. We also uncovered non-synonymous changes, insertions and deletions in these genes, particularly in the polyalanine tract of HOXD13, which are distinctive to cetaceans or convergent with other aquatic mammals. These genetic variations correlated with the diverse and specialized limb structures observed in cetaceans, indicating a complex interplay of relaxed selection and specific mutations in mammalian limb evolution.

Study of internal electric field and interface bonding engineered heterojunction for high stability lithium-ion battery anode

In this paper, SnO2/Ni2SnO4 heterojunctions were grown on NF by a simple secondary hydrothermal method. DFT-based calculations show that the SnO2/Ni2SnO4 heterojunction has excellent thermal stability with a low band gap (1.7 eV) and Li+ diffusion barrier (0.822 eV), which is attributed to the generation of an internal electric field that promotes carrier transport. Electrochemical tests showed that the initial capacity of SnO2/Ni2SnO4/NF was 1401 mAh g-1, and its capacity was 970 mAh g-1 after 200 charge/discharge cycles, which is attributed to metal-oxygen bonds at the interface and a special microsphere structure to improve the stability of the materials. In addition, the electrochemical behavior of SnO2/Ni2SnO4/NF is dominated by capacitive behavior, resulting in excellent rate performance. The synthesis of SnO2/Ni2SnO4/NF provides a reference for designing other heterojunctions anode materials.

Anatomical insights into fish terrestrial locomotion: A study of barred mudskipper (Periophthalmus argentilineatus) fins based on μCT 3D reconstructions.

Mudskippers are a group of extant ray-finned fishes with an amphibious lifestyle and serve as exemplars for understanding the evolution of amphibious capabilities in teleosts. A comprehensive anatomical profile of both the soft and hard tissues within their propulsive fins is essential for advancing our understanding of terrestrial locomotor adaptations in fish. Despite the ecological significance of mudskippers, detailed data on their musculoskeletal anatomy remains limited. In the present research, we utilized contrast-enhanced high-resolution microcomputed tomography (μCT) imaging to investigate the barred mudskipper, Periophthalmus argentilineatus. This technique enabled detailed reconstruction and quantification of the morphological details of the pectoral, pelvic, and caudal fins of this terrestrial mudskipper, facilitating comparison with its aquatic relatives. Our findings reveal that P. argentilineatus has undergone complex musculoskeletal adaptations for terrestrial movement, including an increase in muscle complexity and muscle volume, as well as the development of specialized structures like aponeuroses for pectoral fin extension. Skeletal modifications are also evident, with features such as a reinforced shoulder-pelvic joint and thickened fin rays. These evolutionary modifications suggest biomechanically advanced fins capable of overcoming the gravitational challenges of terrestrial habitats, indicating a strong selective advantage for these features in land-based environments. The unique musculoskeletal modifications in the fins of mudskippers like P. argentilineatus, compared with their aquatic counterparts, mark a critical evolutionary shift toward terrestrial adaptations. This study not only sheds light on the specific anatomical changes facilitating this transition but also offers broader insights into the early evolutionary mechanisms of terrestrial locomotion, potentially mirroring the transformative journey from aquatic to terrestrial life in the lineage leading to tetrapods.

Patients with type 2 diabetes and surgical foot wounds: Overtrust in primary care physicians, isolation, and difficulties contemplating the future

AimsIn Europe, 27 % of patients with a podiatric complication of diabetes are referred to a specialized structure for surgery after more than 3 months’ disease progression. Our study aimed to analyze access to healthcare and future self-projection in patients with severe diabetic foot conditions. MethodsWe performed a qualitative study with semi-structured interviews in patients hospitalized with diabetic foot conditions requiring surgical treatment. We collected quantitative data on the diabetes characteristics, levels of social precariousness, anxiety and depression. ResultsWe conducted 13 interviews with 2 females and 11 males; mean age 62.7 years. Five had undergone surgical debridement, six toe amputation, and two mid-tarsal amputation. Most were socioeconomically deprived and/or isolated. Three discourse themes emerged: 1) heterogeneity in the care pathway, with systemic barriers, negligence or overtrust 2) the relationship between social support and the ability to project oneself into the future, 3) poverty of speech. ConclusionsEducation should emphasize the importance of prompt referral to a specialized structure after the onset of a wound. The lack of support from loved ones and social support appeared to be associated with patients’ failure to plan for their future. We advocate for a psychological evaluation and support for all these patients.

Study on capacity of HPSB hydrogen storage material catalyzed by Sm2O3

HPSB (Hydrolysis Product of Sodium Borohydride) hydrogen storage material is a kind of porous lamellar structural material developed by our research group. Due to the special structure of this material, it can absorb hydrogen at room temperature, hydrogen absorption pressure is 2–4 MPa, and hydrogen absorption time is 2–5 min. The main preparation method used in the experiment is hydrolysis. The main raw material is sodium borohydride, and the reaction temperature is 30 °C. In this experiment, in order to improve the hydrogen storage performance of HPSB hydrogen storage material, Co–B and Sm2O3 were introduced as catalysts during the preparation of HPSB. The results show that the amount of Sm2O3 and the ratio of Sm2O3 to Co–B have obvious influence on the hydrogen storage performance of HPSB. In addition, according to the results of SEM analysis, the amount of Sm2O3 and the ratio of Sm2O3 to Co–B also have obvious effects on the microstructure of HPSB hydrogen storage materials. The sample with a doping amount of 4 wt% and a ratio of Sm2O3 to Co–B of 4:6 can release 2.17 wt% H2.

Enhancement and mechanism of mechanical properties and functionalities of polyacrylamide/polyacrylic acid hydrogels by 1D and 2D nanocarbon

Highly flexible hydrogels are widely used in fields such as agriculture, drug delivery, and tissue engineering. However, the simultaneous integration of excellent mechanical properties, swelling properties, and high electrical conductivity into a hydrogel is still a great challenge. This work introduces 1D tubular multi-walled carbon nanotubes (MWCNTs) and 2D layered graphene oxide (GO) into polyacrylamide/poly-acrylic acid (PAM/PAA) hydrogels. The high specific surface area and oxygen-containing groups of GO contribute to excellent mechanical properties and water absorption of the PAM/PAA hydrogels, but the conductivity is poorly affected due to the presence of defects on GO surface. However, MWCNTs with large aspect ratios benefit to form continuous conductive paths in PAM/PAA hydrogels which further improves conductivity of the hydrogels. MWCNTs are entangled with PAM/PAA molecular chains to form a dense three-dimensional (3D) network structure, and this special structure improves the water absorption of PAM/PAA hydrogels by 3.7 g g−1. What’s more, the MWCNTs/PAM/PAA hydrogel not only provides excellent mechanical properties (compressive strength up to 2.7 MPa), but also has high conductivity (2.3 S m−1). In particular, a strain sensor based on MWCNTs/PAM/PAA hydrogel exhibits exceptional sensitivity (gauge factor = 3.9 at 230–300 % strain) with a rapid response (200 ms) over a wide strain range (50 ∼ 200 %) which enables the ability to precisely and reliably monitor human motion. Therefore, the work provides a new insight into the design of multifunctional hydrogels with application on anatomical water plugging, electronic skin, and biosensors.

A self-supporting nanoflower-like film of 3D walnut shell derived carbon/NiCo2S4 for supercapacitors and zinc-ion batteries with high energy density

Nanocomposites with special structures can generally provide more efficient electron and ion transfer kinetics during electrochemical charge storage, resulting in satisfactory energy densities. Herein, we adopted a simple hydrothermal method to prepare a nanoflower-like NiCo2S4 growing on hierarchical porous N, O co-doped walnut shell-derived carbon (10-WSC-N/O@NiCo2S4). Metal ions (Ni2+, Co2+) enhanced the active site to obtain better electrochemical activity, as well as the porous carbon framework helped achieve better ion transport and electron conduction. Importantly, 10-WSC-N/O@NiCo2S4 exhibits 1176 F g−1 at 0.5 A g−1, the prepared 10-WSC-N/O@NiCo2S4//WSC-N/O displays a remarkable energy density of 68.6 Wh kg−1 at 375 W kg−1 and only decreases a 12 % in capacitance after 8000 cycles at 3.0 A g−1. Additionally, the 10-N/O@NiCo2S4//Zn device achieves a high energy density of 88.54 Wh kg−1 at 750 W kg−1. Overall, this work provides an efficient strategy for fabricating high-performance electrode materials.

The synergistic mechanism of ultrasonic and heat treatment on the composite structure and mechanical properties of Nb-Si-Zr based in-situ composites

Ultrasonic assisted solidification (UST), heat treatment and alloying are all effective methods to control the microstructure of materials and improve their properties. In this paper, the Nb-16Si-20Zr-2C-xW composites were prepared using ultrasonic assisted solidification technology of high temperature melt (≥1800℃) and heat treatment. The influence mechanism of ultrasonic, the W element, and the synergistic regulation mechanism of ultrasonic and heat treatment on the material were studied. Nb-16Si-20Zr-2C-xW(UST) alloys are mainly composed of Nbss phase and γNb5Si3 phase, and their microstructures are mainly divided into strong active zone(SZ) and weak active zone(WZ). In the Nb-Si superalloy melt treated by ultrasonic wave, the area near the ultrasonic sound source is the strong active zone, while the area far away from the ultrasonic sound source is the weak active zone. The features of faceted primary phases and non-faceted primary phases in the SZ and WZ are explained by the equation of undercooling degree at different interfaces and effect of ultrasonic on component undercooling. As the W element content in the alloys (UST) increases, the content of the Nbss phase increases, the median diameter of the primary γNb5Si3 phase decreases, and the room temperature fracture toughness and compressive strength show an upward trend. When the addition amount of W element reaches 2 at%, there are more crack deflections, crack bridging and secondary cracks in the crack propagation path. Through the special arrangement of primary γNb5Si3 phase in the ultrasonic field, the energy density of ultrasonic waves in the melt is calculate to be 33.5 kW/m2. The microstructure of Nb-16Si-20Zr-2C-xW alloys(UST+HT) became more uniform and spheroidize. It is worth mentioning that there are plenty of long strip γNb5Si3 phases with different orientations in the Nb-16Si-20Zr-2C-0.1W(UST+HT) alloy and the long strip γNb5Si3 phases with the same orientation are arranged in a periodic manner. This special composite structure induces crack deflections and branching cracks when cracks propagation, so the room temperature fracture toughness of Nb-16Si-20Zr-2C-0.1 W (UST+HT) alloy reaches 15.66 MPa·m1/2.

Aromatic Biobased Polymeric Materials Using Plant Polyphenols as Sustainable Alternative Raw Materials: A Review.

In the foreseeable future, the development of petroleum-based polymeric materials may be limited, owing to the gradual consumption of disposable resources and the increasing emphasis on environmental protection policies. Therefore, it is necessary to focus on introducing environmentally friendly renewable biobased materials as a substitute for petroleum-based feed stocks in the preparation of different types of industrially important polymers. Plant polyphenols, a kind of natural aromatic biomolecule, exist widely in some plant species. Benefiting from their special macromolecular structure, high reactivity, and broad abundance, plant polyphenols are potent candidates to replace the dwindling aromatic monomers derived from petroleum-based resources in synthesizing high-quality polymeric materials. In this review, the most related and innovative methods for elaborating novel polymeric materials from plant polyphenols are addressed. After a brief historical overview, the classification, structural characteristics, and reactivity of plant polyphenols are summarized in detail. In addition, some interesting and innovative works concerning the chemical modifications and polymerization techniques of plant polyphenols are also discussed. Importantly, the main chemical pathways to create plant polyphenol-based organic/organic-inorganic polymeric materials as well as their properties and possible applications are systematically described. We believe that this review could offer helpful references for designing multifunctional polyphenolic materials.

Enhancing Ce-Co interfacial effects via special petal-pollen morphology construction to achieve efficient toluene removal

Interfacial effects provide an effective means to construct multi-metal interactions and design efficient catalysts for VOCs purification, while morphology construction remains a common tactic to optimize the efficiency of these catalysts. In the present work, the Co-Ce bimetal interface was effectively constructed by morphological regulation, and the coupling of the interfacial effect modulation and the special morphological structure was realized, resulting in superior catalyst performance. Among the series catalysts, CeCoOx-H demonstrated the optimized activity with 90 % toluene conversion at 250 °C while maintaining good results in a 50 h stability test. And the systematic characterization revealed that the structural changes and interfacial effects induced by morphological modulation would increase the structural defects, improving surface reactive oxygen and oxygen vacancy content, oxygen storage capacity, oxygen motivity and low-temperature reductivity, which account for promising catalytic performance of CeCoOx-H. Furthermore, in-situ DRIFTS revealed the following decomposition routes for toluene on the CeCoOx-H catalyst surface: toluene → benzyl alcohol → benzaldehyde → benzoate → phenol → maleate → acetate → formate → carbon dioxide. In particular, the decomposition of benzaldehyde and benzoate may be the key steps in toluene catalytic oxidation. Also, the characterization unveiled that the rich adsorption sites brought by the interfacial construction are not negligible in boosting the catalytic performance.

Eu-MOF-based highly sensitive and selective luminescence probe for trace, in situ and visual detection of flunitrazepam

Flunitrazepam, as an emerging new psychoactive substance classified as a third-generation drug that is more harmful and camouflaged, is gradually proliferating globally. Maliciously used as a criminal tool in homicide and rape cases, it has already caused serious harm to public safety and social stability. Owing to its special molecular structure, low concentration level and rapid metabolic process in the human body, accurate detection of flunitrazepam remains a major challenge, especially for real sample and on-site detection. In this paper, a lanthanide MOF (Eu-MOF) based on bi-ligand was constructed as a luminescence probe and used for the first time to detect trace amounts of flunitrazepam. The ’antenna effect’ promotes strong luminescence of Eu-MOF, while the lower LUMO orbital energy level of flunitrazepam allows it to accept electrons from the electron donor leading to quenching of Eu-MOF luminescence. The probe has a high sensitivity and can detect flunitrazepam in the range of 0–800 μM with a detection limit as low as 73 nM. Moreover, flunitrazepam was detected in urine from real samples as well as in a variety of beverages to further validate its accuracy and practicality. The reported Eu-MOF represents one of the pioneering luminescence probes for the detection of flunitrazepam, which offers great promise for the on-site or on-line analysis of flunitrazepam.

Degree of Crystal Structure Distortion-Induced Tunable LiGaO2 Long Persistent Luminescence for Optical Information Encryption.

Tunable long persistent luminescence (LPL) phosphor materials have great potential for optoelectronic cryptographic applications. However, the mainstream techniques of modulating LPL generally have the characteristics of complex preparation processes, demanding crystal field environments, or expensive dopant ions, which restrict large-scale commercial application. Herein, we develop a simple, high-efficiency, and low-cost strategy to optimize the LPL of LiGaO2(LGO):Cu2+ by changing the sintering time to regulate the degree of crystal structure distortion. The Cu2+ as charge compensation will substantially enhance the emission intensity of LGO by a factor of 11.02 originating from the appropriate ionic size and coordination mode. Besides, the LPL time of LGO:Cu2+ can be extended effectively to 2 h by adjusting the sintering temperature and time (900 °C@24 h). The extension mechanism is that Li and Ga can be substituted for each other more easily and induce crystal structure distortion due to the special crystal structure of LGO, resulting in an optimal trap concentration in LGO:Cu2+. Thus, our findings provide a simple way to modulate long persistent luminescence and further consider their potential impact on optical information encryption.

Enhanced hydrothermal stability by a semi-embedded structure: An efficient Ru catalyst for levulinic acid conversion in the aqueous phase

Catalyst stability is believed to be one of the greatest challenges faced for the supported metal catalysts in the catalytic conversion of biomass and its derivatives because many biomass transformations are conducted in the aqueous phase. In this work, we report a simple yet efficient coating-impregnation-pyrolysis (CIP) strategy to fabricate Al2O3 supported Ru catalyst (Ru-Al2O3@CN) with Ru NPs (nanoparticles) semi-embedded into N-doped carbon (CN) layer for the efficient hydrogenation of levulinic acid (LA) to γ-valerolactone in the aqueous phase. Benefit from the special structure of Ru-Al2O3@CN catalyst, it possesses both high catalytic activity and stability, giving a TOF of 28,099 h-1 for LA hydrogenation at 120 °C and 2 MPa H2, which is superior to the most of reported Ru-based catalysts. More importantly, compared with conventional impregnated Ru/Al2O3 catalyst, the Ru-Al2O3@CN catalyst exhibits a remarkably improved hydrothermal stability. Based on series of catalyst characterizations and control experiments, it was found that the presence of CN can weak the interaction between Ru and Al2O3, as well as protect the Al2O3 and Ru NPs from hydrolysis and aggregation, respectively. We anticipate that such a novel strategy may provide some valuable insights into the synthesis of oxides-supported metal catalyst with high hydrothermal stability.

UV aging resistance improvement of SBS modified asphalt binder by organic layered double hydroxide and naphthenic oil: Its preparation, properties and mechanism

To enhance the UV aging resistance of SBS modified asphalt, LDHs and naphthenic oil were selected to modify it compositely. Firstly, organic treatment for LDHs was carried out through the combination of surface modification method and intercalation modification method to improve its compatibility with asphalt, and effectiveness of organic treatment was evaluated through the microscopic testing methods. Then, organic LDHs/SBS modified asphalt binders were developed by melt blending method, on this basis, appropriate naphthenic oil was added for composite modification. Subsequently, the conventional physical properties, storage stability and rheological properties tests were carried out to evaluate the comprehensive properties of the prepared modified asphalt containing LDHs and naphthenic oil. On this basis, TOPSIS method was conducted for multi-index optimization to determine the optimal dosages of LDHs and naphthenic oil. Finally, UV aging resistance of the developed modified asphalt was also evaluated, and reaction mechanism was explored with FTIR and FM. Test results show that stearic acid (SA) was successfully absorbed on the surface of LDHs, and -SO32- in ultraviolet light absorber (UVT) has successfully entered the interlayer galleries of LDHs, thus achieving the organic treatment for LDHs. Organic LDHs can significantly improve the high temperature properties and storage stability of SBS modified asphalt, and naphthenic oil can also improve the storage stability of SBS modified asphalt at the proper dosage. In addition, the two modifiers can both effectively improve the UV aging resistance of SBS modified asphalt. Based on the multi-index optimization results, it is recommended that the optimal dosages of LDHs and naphthenic oil are 2 % and 2.5 %, respectively, and at this conditions, comprehensive properties of the prepared modified asphalt can achieve the best. Microstructure characterization tests results reveal that LDHs and naphthenic oil are only simply dispersed in asphalt and do not cause the structural damage of SBS modified asphalt. Meanwhile, the special layered structure of LDHs can hinder the mobility of asphalt molecular chains, which enhances the interaction force between asphalt molecular chains and SBS modifier molecular chains, thus improving the road properties of SBS modified asphalt.

Achieving Significantly Boosted Dielectric Energy Density of Polymer Film via Introducing a Bumpy Gold/Polymethylsilsesquioxane Granular Blocking Layer.

Polymer dielectrics are the key materials for pulsed energy storage systems, but their low energy densities greatly restrict the applications in integrated electronic devices. Herein, a unique bumpy granular interlayer consisting of gold nanoparticles (Au NPs) and polymethyksesquioxane (PMSQ) microspheres is introduced into a poly(vinylidene fluoride) (PVDF) film, forming trilayered PVDF-Au/PMSQ-PVDF films. Interestingly, the Au/PMSQ interlayer arouses a dielectric enhancement of 47% and an ultrahigh breakdown strength of 704MVm-1, which reaches 153% of pure PVDF. It is revealed that the greatly enhanced breakdown strength originated from the Coulomb-blockade effect of Au NPs and the excellent insulating properties of PMSQ microspheres with a special molecular-scale organic-inorganic hybrid structure. Benefiting from the concurrently enhanced dielectric and breakdown performances, an outstanding energy density of 22.42Jcm-3 with an efficiency of 67.1%, which reaches 249% of that of the pure PVDF, is achieved. It is further confirmed that this design strategy is also applicable to linear dielectric polymer polyethyleneimine. The composites exhibit an energy density of 8.91Jcm-3 with a high efficiency of ≈95%. This work offers a novel and efficient strategy for concurrently enhancing the dielectric and breakdown performances of polymers toward pulsed power applications.

CRACKING PATTERN ANALYSIS OF THE TURNING BAND METHOD (TBM) APPLICATION ON A SINGLE-REINFORCEMENT BAR CONCRETE BEAM MODELLING USING THE MAZARS DAMAGE

The development of crack patterns in reinforced concrete structures is a randomly stochastic process influenced by the heterogeneous nature of concrete materials, which impacts the sensitivity to damage and variability in mechanical properties. The numerical simulation of damage pattern appearance on the reinforced concrete for special building structures needs a realistic result, especially in terms of crack distribution. The Turning Band Method (TBM) serves as a tool for assessing the variability of concrete heterogeneity, functioning as an operator to generate a random variable for each specific field. In this study, the investigation of crack patterns in reinforced concrete structures involves using a simple concrete beam sample, measuring 10x10x50 cm3, with a single longitudinal reinforcement cast in the centre. This beam is subjected to an axial tensile loading, while the Mazar Damage Model is employed as the concrete behaviour law. Through the implementation of The Turning Band Method (TBM) and the variation of the random field parameters, distinct crack patterns are observed, not only the number but also the locations of cracks. The use of a smaller correlation length showed 2 cracks while the larger size had around 1 to 3 cracks, with the first crack localizations of each sample generally occurring in the middle surface, in which a noticeable contrast to non-TBM modelling just displays 1 crack. Furthermore, the resulting probability of cracks for ten random draws demonstrates similarity to experimental tests and numerical simulation of the previous study, both at global and local levels.

Trefoil-like COFs membrane fabricated by interfacial polymerization for dye/salt separation

Covalent organic frameworks (COFs) with β-ketoenamine structure have shown notable effectiveness in water treatment. In general, COFs can be constructed by the interfacial polymerization (IP) between a C2 symmetry monomer with para-position reaction groups and a C3, C4 and C6 symmetry functionalized monomer. The constrained availability of para-position monomers limits the diversity of COFs synthesis options, necessitating exploration into non-para-position alternatives. Herein, 2,4,6-triformylphloroglucinol (Tp) and ortho-position monomer o-phenylenediamine (OPD) are employed to fabricate a composite membrane featuring COFs with a special trefoil-like structure by interfacial polymerization method. The optimal OPD-Tp COFs/Nylon nanofiltration (NF) membrane has 99.8 % rejection for CR and only 3.2 % rejection for NaCl. Meanwhile, the pure water permeation flux is 132 L m−2 h−1 bar−1. This study shows the significant potential for dye/salt separation of the prepared COFs composite NF membrane and broadens the monomer selective range for the COFs membrane fabrication.

The effect of hemicelluloses on biosynthesis, structure and mechanical performance of bacterial cellulose-hemicellulose hydrogels

The primary plant cell wall (PCW) is a specialized structure composed predominantly of cellulose, hemicelluloses and pectin. While the role of cellulose and hemicelluloses in the formation of the PCW scaffold is undeniable, the mechanisms of how hemicelluloses determine the mechanical properties of PCW remain debatable. Thus, we produced bacterial cellulose–hemicellulose hydrogels as PCW analogues, incorporated with hemicelluloses. Next, we treated samples with hemicellulose degrading enzymes, and explored its structural and mechanical properties. As suggested, difference of hemicelluloses in structure and chemical composition resulted in a variety of the properties studied. By analyzing all the direct and indirect evidences we have found that glucomannan, xyloglucan and arabinoxylan increased the width of cellulose fibers both by hemicellulose surface deposition and fiber entrapment. Arabinoxylan increased stresses and moduli of the hydrogel by its reinforcing effect, while for xylan, increase in mechanical properties was determined by establishment of stiff cellulose–cellulose junctions. In contrast, increasing content of xyloglucan decreased stresses and moduli of hydrogel by its weak interactions with cellulose, while glucomannan altered cellulose network formation via surface deposition, decreasing its strength. The current results provide evidence for structure–dependent mechanisms of cellulose–hemicellulose interactions, suggesting the specific structural role of the latter.