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A pivotal limitation in the widespread adoption of geopolymer stems from their notable and substantial drying shrinkage properties, which significantly constrain their potential applications. The complex reaction processes and amorphous gel structures make it difficult to quantitatively calculate the drying shrinkage rate. In this study, alkali-activated slag-metakaolin-based geopolymer was used to develop a method for predicting drying shrinkage. By analyzing the internal relative humidity changes, contact angles on the structure surface at different ratios, and the surface tension of pore solutions, the capillary tensile stress within the structure was calculated. This analysis was combined with measurements of drying shrinkage, elastic modulus, and porosity to establish a predictive method for the drying shrinkage of alkali-activated slag-metakaolin-based geopolymer. The results indicated that as the system's relative humidity decreased, the surface tension of the pore solution increased, the interface contact angle reduced, and the capillary tensile stress, as calculated using the Young-Laplace equation, increased. These changes intensified the microstructural shrinkage and, consequently, increased the geopolymer's overall shrinkage rate. At the same time, the larger the porosity of the geopolymer system, the smaller the elastic modulus, the larger the dry shrinkage rate of the geopolymer. At a porosity of 29.0 %, an elastic modulus of 1.83 GPa, and a capillary tensile stress of 3.6 MPa, the dry shrinkage of the geopolymer is only 0.899 %. By adjusting the porosity and elastic modulus to 38.3 % and 1.60 GPa, respectively, and increasing the capillary tensile stress to 10.84 MPa, the dry shrinkage of the geopolymer reaches a maximum of 1.942 %. The prediction method for geopolymer drying shrinkage, established based on these factors, has a correlation coefficient of 0.97, effectively predicting the trend of geopolymer drying shrinkage rate characteristics. The current study provides a theoretical basis for methods to reduce shrinkage in geopolymers and their application in engineering. • The drying shrinkage performance of Alkali-activated Slag Metakaolin (ASM) based geopolymer was studied. • Drying shrinkage is quantified by capillary pulling force. • Propose a method to predict the drying shrinkage of ASM-based geopolymer under multi-factor conditions. [ABSTRACT FROM AUTHOR]

Comparative proteomics and non-target metabolomics, together with physiological and microstructural analyses of wheat grains (at 15, 20, 25, and 30 days after anthesis) from two different quality wheat varieties (Gaoyou 5766 (strong-gluten) and Zhoumai 18) were performed to illustrate the grain filling material dynamics and to search for quality control genes. The differential expressions of 1541 proteins and 406 metabolites were found. They were mostly engaged in protein metabolism, stress/defense, energy metabolism, and amino acid metabolism, and the metabolism of stored proteins and carbohydrates was the major focus of the latter stages. The core proteins and metabolites in the growth process were identified, and the candidate genes for quality differences were screened. In conclusion, this study offers a molecular explanation for the establishment of wheat quality, and it aids in our understanding of the intricate metabolic network between different qualities of wheat at the filling stage. [Display omitted] • Different quality wheat exhibit variations in indicators, protein, and starch development. • Proteomics and metabolomics of different quality wheat were analyzed in combination. • Selected some important proteins and metabolites during the wheat filling process. • Selected some possible gluten quality differential proteins (genes). [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) show promising prospect as the photocatalysts with advantages of exceptional light adsorption capability, large specific surface area, and adjustable band structure. However, COFs usually suffer from severe recombination of photogenerated carriers. Therefore, there is an urgent demand to design effective COF-based heterostructures to enhance the separation of carriers. In this work, a porphyrin-based COF with electron donor-acceptor structure is synthesized via condensation polymerization by using 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (TAPPP) and N,N,N',N'-tetra(4-formylphenyl)benzidin (NFPBD) as the donor and acceptor, respectively. Subsequently, ZnIn 2 S 4 (ZIS) are successfully in-situ grown on the surface of porphyrin-based COF, forming a novel core-shell structure. The in-situ synthesized ZIS with positive charges can be easily adsorbed on the negatively charged sites of the COF's surface via the electrostatic interaction. This organic/inorganic hybrid COF-ZIS heterostructure exhibits a superior photocatalytic hydrogen evolution (PHE) rate of 695 μmol g−1 h−1, approximately three times higher than that of ZIS. The construction of COF-ZIS heterostructure plays an important role in enhancing the separation and transport of photogenerated carriers, which provides more electrons at the surface of ZIS to take part in proton reduction. Electron paramagnetic resonance spectra confirm the charge carriers transfer mode in the COF-ZIS heterostructure via an S-scheme mechanism. Moreover, upon loading Pt as the cocatalyst, the heterostructure achieves an effective PHE rate of 2711 μmol g−1 h−1 along with an exceptional stability. Additionally, the COF-ZIS heterostructure reaches up to 2.45% of apparent quantum efficiency at 400 nm. Notably, the average lifetime of the COF-ZIS heterostructure increases by 43.2% and 98.9% compared to that of ZIS and the COF individually, as observed through single-particle fluorescence spectroscopy. This work gives valuable inspiration into the building of donor-acceptor COF-based S-scheme heterostructures to achieve highly effective green energy conversion by aligning band structures. [Display omitted] • A novel organic/inorganic core-shell heterostructure was created through the in situ growth of ZnIn 2 S 4 (ZIS) on the surface of the donor-acceptor COF. • The photogenerated electrons were transferred from the LUMO energy level of COF and paired with the holes at the VB of ZIS to form an S-scheme heterostructure, leading to a 3-fold accumulation of electrons at the surface of ZIS. • The construction of the COF-ZIS heterostructure with Pt co-catalyst demonstrated an efficient photocatalytic H 2 evolution rate of 2711 μmol g−1 h−1, resulting in an approximately 4-fold increase in photocatalytic activity by enhancing the utilization of carriers. • The COF-ZIS heterostructure exhibited an excellent photocatalytic cycle stability and achieved a high apparent quantum efficiency of 2.45% at 400 nm. [ABSTRACT FROM AUTHOR]

• Bond strength between the geopolymer and aggregate is higher compared to cement. • Bond strength decreases with increase of activator modulus and liquid/solid ratio. • The microhardness of ITZ is lower than that of the geopolymer binder. • The crack width in ITZ increases with activator modulus and liquid/solid ratio. • The microhardness of ITZ decreases with activator modulus and liquid/solid ratio. The application of geopolymers as an alternative to Portland cement has received significant attention in concrete development due to the promotion of sustainability. Interfacial transition zone (ITZ) has been characterized as the weakest link in ordinary Portland cement concrete and usually deteriorates the mechanical properties and durability of concrete. To further understand the performance of geopolymeric concrete, the microstructure and properties of the interface zone in geopolymeric concrete are investigated in this study. Metakaolin and ground granulated blast-furnace slag (GGBFS) were used as the raw materials for geopolymer synthesis. Cubic splitting tests were conducted to investigate the interfacial bond strength between the geopolymer and the granite aggregate for different activator moduli and liquid/solid ratios. The morphology and mechanical properties of the ITZ between the geopolymer and granite aggregate were studied with the aids of scanning electron microscopy, energy-dispersive X-ray spectroscopy, and microhardness testing. The results indicate that the bond strength between the geopolymer and aggregate is higher than that between the cement paste and granite aggregate, and it decreases with the increase of the activator modulus and liquid/solid ratio. An ITZ was observed between the geopolymer paste and granite aggregate, and its microstructure and chemical components were different from those of the geopolymer. Obvious inhomogeneity can be observed for the ITZ along the aggregate body. The microhardness of the ITZ is lower than that of the geopolymer binder, and an increase in the activator modulus and liquid/solid ratio leads to an increase in the width of the crack in the ITZ and a decrease in the microhardness. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • ZnO/carbon nanotube composites as anode materials are synthesized by physical mixing and chemical filling methods. Electrochemical performance of the Ni-Zn batteries synthesized by chemical filling method is far better than that by the physical mixing method • The discharge capacity and cycle life of the newly designed Ni-Zn batteries can reach 410 mAh/g and 600 times, respectively. Abstract The cycle life of Ni-Zn secondary batteries is largely affected by the dissolution of zinc anode active substances. ZnO/carbon nanotube composites as anode materials are synthesized by physical mixing and chemical filling methods to reduce the dissolution of active substances and improve the electrochemical performance of Ni-Zn batteries. By performing electrochemical testing to the Ni-Zn batteries with anode materials of ZnO/carbon nanotube composites prepared by the two different synthesis methods, we find that the electrochemical performance of the Ni-Zn batteries with anode materials of ZnO/carbon nanotube composites synthesized by chemical filling method is far better than that synthesized by the physical mixing method, with discharge capacity of 410 mA h/g and achievable cycle life of about 600 times. The experimental results pave the way for applications of carbon nanomaterials to the optimal design of zinc anode of Ni-Zn secondary batteries. [ABSTRACT FROM AUTHOR]

• A novel fault measure and early warning system for air compressor is proposed. • PCA-BP based variable selection are applied to simplify the MEST model. • A deviation function is defined to calculated the deviation sequence. • Sliding window method is applied to determine the fault early warming threshold. Air compressor is a main power equipment, and improving its reliability and security is important to enhance the competitiveness of pneumatic companies. This study proposes a real monitored data-based fault measure and early warning system for air compressor, which can guide field workers in economically and safely operating the air compressor by finding and dealing with faults ahead of time. A data-driven multivariate state estimation technique (MSET) is utilized to construct the non-parametric fault early warning model under normal operating condition, principal components analysis (PCA) and back propagation (BP) method are combined to construct the dynamic memory matrix and simplify the model. With the pre-built PCA-BP-MSET model, optimal values of the observed vectors are estimated and a deviation function is defined to calculated the deviation sequence between the estimated and observed vectors, where the qualitative-quantitative combined AHP method is adopted to determine the weights of the monitored variables. With the deviation sequence, the sliding window statistical method is applied to determine the fault early warming threshold, which can be used as a benchmark to measure and warn the fault of air compressor. The fault warning information of an air compressor is given out once the deviation degree of some observed vector exceeds the threshold, thereby realizing the function of fault measure and early warning in advance. In addition, an automatically updating method is proposed to ensure the accuracy of the PCA-BP-MSET model in case of the changes of running states. For verification, a real fault case of an air compressor has been chosen to verify the effectiveness of the proposed method. Result shows that the PCA-BP-MSET-based method can catch the fault developing process timely, which is appropriate for the faults prevention and rapid troubleshooting of air compressor. [ABSTRACT FROM AUTHOR]

Abstract Mineral resources are still the rigid demand of China's development and their sustainability assessment is central to regional development. This paper introduces an improved Analytic Hierarchy Process-based Normal cloud model which incorporated randomness and fuzziness and presents an index system applicable to empirical analysis on 31 provinces of China. The weight system of evaluation indicators is determined by an improved analytic hierarchy process (IAHP) approach with good accessibility and attainability. Regional disparities of resources sustainability are demonstrated by spatial distributions of mineral resources sustainability with the help of GIS technology. The sustainability level is determined by the combination of resources, environment and society dimensions. The results indicate that the areas with high sustainability do not necessarily happen in resource-rich regions. The most important implications are the relatively lower sustainability of the developed areas and the higher sustainability in western provinces. The scores for indicators reveal that compared with western and central areas, the coastal provinces are less sustainable in environmental carrying capacity, but with higher sustainable social supporting capacity. Robustness test notes that the results are sensitive to the adjustment of weight system due to the preference of decision makers. Finally, differentiated regional strategies for improving overall sustainability are proposed. Graphical abstract Image Highlights • Normal cloud model is applied to assess sustainability of mineral resources (SMR). • An assessment system of SMR is developed for Chinese province. • The weights are obtained by improved analytic hierarchy process and an expert survey. • Resource-rich areas have high levels of SMR but with some exceptions. • Regional SMR is sensitive to the preference of decision makers. [ABSTRACT FROM AUTHOR]

Photoinduced charge carrier separation derived by magnetic fields has attracted increasing attention for its ability to wireless regulate powder photocatalysts. In this study, carbon nanotubes (CNT) were used as network conductors to link ZnIn 2 S 4 nanosheets. The electron highway in CNT spontaneously enhanced the photoinduced charge carrier transfer between ZnIn 2 S 4 nanosheets. The photocatalytic H 2 evolution rate of the 3 wt % CNT-ZIS composite increased to ∼210 % compared to that of pure ZIS under 300 W xenon lamp illumination. Additionally, in a magnetic field with relative motion, the Lorenz force on photoinduced electrons and holes suppressed their recombination, while the motional electromotive force along CNT accelerated the electron transfer to surface active sites. Therefore, the photocatalytic H 2 evolution rate further increased to 290 %. The spontaneous and passive photoinduced charge carrier separation in CNT-ZnIn 2 S 4 network composites under a magnetic field contributed to enhanced photocatalysis. Moreover, CNT-based network semiconductor composites can be mass-produced at low cost. Magnetic field-enhanced photocatalysis can be universally achieved without limitation caused by intrinsic band structures. [Display omitted] • The electron highway in CNT network connects the ZnIn 2 S 4 nanosheets. • CNT current collector enhances charge transfer between ZnIn 2 S 4 nanosheets. • A strategy to apply electromagnetic induction in composite nanocatalysts. • Magnetic field enhanced photocatalysis can be universally achieved accordingly. [ABSTRACT FROM AUTHOR]

The present study describes a positive regulatory loop between SJP and the SDF-1α/CXCR4 axis in NSC migration. The treatment of NSCs with SJP and SDF-1α increases the cell migration capacity and promotes cell migration from the neurospheres. These effects are accompanied by the up-regulation of Nestin, N-cadherin, TLR4, TNF-α, Cyclin D1, EGFR, Alpha 6 integrin, MMP-2, MMP-9, and iNOS, including SDF-1α and CXCR4 themselves. However, these effects are blocked by AMD3100, LY294002, U0126, and PDTC. SJP enhances the SDF-1α/CXCR4 axis-induced MMP-2 and MMP-9 secretion and NO release. Results demonstrate that interaction of SJP with the SDF-1α/CXCR4 axis regulates NSC migration via the PI3K/Akt/FOXO3a, ERK-MAPK, and NF-κB signaling pathways. [ABSTRACT FROM AUTHOR]

In the actual production, measuring the complexity of set point signals for a control system has practical significance. This paper proposes a new method for the complexity measure aiming mostly at set points of a system. Firstly, a standard SISO (Single Input Single Output) system is built as the complexity test system. Complexity index of a set point signal is defined based on the IAE (Integrated Absolute Error) performance. Then, a general complexity measure method is introduced for common set point signals. At last, complexity of some common set points and the AGC (Automatic Generation Control) orders for a power plant are analyzed. Tests and comparisons of the new method with two traditional methods (Lempel–Ziv complexity approach and Sample Entropy-Based approach) have shown that the IAE-based measure method introduced in this paper is reasonable and suitable for the complexity measurement of a set point signal in a control system. [ABSTRACT FROM AUTHOR]

Abstract: Polypyrrole/vanadium oxide nanotubes (PPy/VOx-NTs) as a new high-performance cathode material for rechargeable lithium-ion batteries are synthesized by a combination of hydrothermal treatment and cationic exchange technique. The morphologies and structures of the as-prepared samples are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry and differential scanning calorimeter (TG–DSC) and X-ray powder diffraction (XRD). The results indicate that the organic templates are mainly substituted by the conducting polymer polypyrrole without destroying the previous nanotube structure. Their electrochemical properties are evaluated via galvanostatic charge/discharge cycling, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It is found that PPy/VOx-NTs exhibit high discharge capacity and excellent cycling performance at different current densities compared to vanadium oxide nanotubes (VOx-NTs). After 20 cycles, the reversible capacity of PPy/VOx-NTs (159.5mAhg−1) at the current density of 80mAg−1 is about four times of magnitude higher than that of VOx-NTs (37.5mAhg−1). The improved electrochemical performance could be attributed to the enhanced electronic conductivity and the improved structural flexibility resulted from the incorporation of the conducting polymer polypyrrole. [Copyright &y& Elsevier]

Abstract: A new kind of cathode materials for rechargeable lithium-ion batteries, lithium vanadium oxide nanotubes synthesized by a combined sol–gel reaction and hydrothermal treatment procedure is reported in this paper. SEM, TEM, XRD and XPS techniques were performed to investigate the morphology and structure of the resulting materials. The results confirmed that the synthetic materials are composed of uniformly open-ended multiwalled nanotubes with a length from 1 to 3μm. The inner and the outer diameters of the obtained nanotubes vary from 30 to 50nm and 50 to 120nm, respectively. The electrochemical performance as a cathode material was examined and evaluated by cyclic voltammetry, galvanostatic charge–discharge cycling and AC impedance spectroscopy techniques. The results indicated that the resultant lithium vanadium oxide nanotubes have a high initial discharge capacity of 457mAhg−1 in the potential range of 1.0–4.0V (vs. Li/Li+) and good cycling performance. The improved electrochemical performance of the products should be due to its special one-dimensional multiwalled tubular structure and the contribution of lithium-ions. [Copyright &y& Elsevier]

The selective photocatalytic oxidation of alcohols to aldehydes is difficult to accomplish in pure water, which is a substantial obstacle for the practical application of the photocatalytic synthesis of aldehydes. In this work, a composite photocatalyst was constructed by assembling Ni(OH) 2 on a CdS-MoS 2 heterostructure, which allowed for the effective photocatalytic oxidation of benzyl alcohol to benzaldehyde by photogenerated holes in anaerobic pure water. The conversion of benzyl alcohol was increased from 18.9% to 94.2%. Ni(OH) 2 loaded on CdS-MoS 2 could serve as a hole-transport layer, enhancing the transport of holes to the catalytic surface to achieve more efficient benzyl alcohol oxidation. A part of Ni2+ was reduced to Ni0 by a small amount of photoinduced electrons. Both Ni2+ and Ni0 adsorbed the α-H of benzyl alcohol, which was the dehydrogenation unit, thus providing more active sites for the conversion of benzyl alcohol to benzaldehyde. The self-reduction of Ni2+ on the surface may be reduced to Ni0 and it may protect the inner Ni2+ from self-reduction due to the fast electron transfer and electron active site, which benefited the photocatalytic stability of the Ni(OH) 2 -modified CdS-MoS 2 heterostructures. The synergistic effect of Ni(OH) 2 and metallic Ni significantly improved the photocatalytic oxidation properties. The effective photocatalytic oxidation of benzyl alcohol to benzaldehyde by photogenerated holes in anaerobic pure water is realized by assembling Ni(OH) 2 on a CdS-MoS 2 heterostructure. The synergistic effect of Ni(OH) 2 and metallic Ni can significantly improve the photocatalytic oxidation properties. Visible light was applied as an efficient energy source to induce alcohol oxidation under ambient conditions. [Display omitted] • The Ni(OH) 2 loaded on CdS-MoS 2 could serve as a hole-transport layer to enhance the hole transport to the catalytic surface for taking part in the benzyl alcohol oxidation. • Part of Ni2+ could be reduced to Ni0 by a small amount of electrons. Both Ni2+ and Ni0 could adsorb the α-H of benzyl alcohol, which was the dehydrogenation unit, thus providing more active sites to enhance the oxidation of benzyl alcohol. • The synergistic effect of Ni(OH) 2 and metallic Ni were responsible for the significant improvement of photocatalytic oxidation property. [ABSTRACT FROM AUTHOR]

In this study, we reported the occurrence of eight organophosphorus pesticides (OPPs) in the East China Sea. Forty samples were collected and analysed with a high volume solid phase extraction method (Hi-throat/Hi-volume SPE) in the early summer of 2020. All the target OPPs were detected in the surface water at one or more stations in the East China Sea, and the concentrations of ΣOPPs were in the range 0.0775–3.09 ng/L (mean: 0.862 ± 0.624 ng/L). Terbufos sulfone and fenthion were the main pollutants in this area, probably resulting from pesticide use in China and other countries. The off-shore input from coastal regions was suggested to be a major source of OPP pollution in the East China Sea, and the movement of ocean currents played an important role in their transportation because around 0.86 t OPPs passed through the Tsushima Strait from the East China Sea each month. An ecological risk assessment showed that these OPPs presented a high risk to species in the East China Sea, whereas they posed no health risk to humans under both the median and high exposure scenario. [Display omitted] • Hi-throat/Hi-volume SPE was suitable for collecting and analyzing OPPs in seawater. • The total concentration of eight OPPs was 0.0775–3.09 ng/L in the East China Sea. • Around 0.86 t OPPs entered the Japan Sea from the East China Sea per month. • There was a high ecological risk of OPPs to organisms in the East China Sea. Hi-throat/Hi-volume SPE is effective in the collection and analysis of OPPs in seawater, and there is emerging risk of OPP exposure to organisms in the East China Sea. [ABSTRACT FROM AUTHOR]

• We reported 10 (3.0 %) tet (X5)- and tet (X6)-positive MDR A. baumannii isolates from sick animals. • Both the tet (X5)- and tet (X6)-positive A. baumannii strains could inactivate tetracyclines by hydroxylation. • The plasmid-borne tet (X5) and chromosomal tet (X6) genes shared homologous genetic structures with those of clinical strains. • A clonal spread of ST355 A. baumannii strains as well as IS CR2 -mediated transposition for tet (X) genes was discovered. The recent emergence of plasmid-mediated tigecycline resistance gene tet (X) has challenged the clinical effectiveness of tigecycline as a last-resort treatment option. During 2017–2018, 336 fecal samples from sick ducks, pigs, chickens and geese in Guangdong, China, were screened for tet (X)-positive Acinetobacter baumannii strains. Their activities on tetracyclines were determined by microbiological degradation and mass spectrometry, followed by susceptibility testing, sequence typing, gene transfer, molecular location and genomic DNA sequencing analyses. A total of 10 tet (X)-positive A. baumannii strains were isolated from ducks and chickens, including eight plasmid-borne tet (X5)-positive and two chromosomal tet (X6)-positive isolates. All of them exhibited good degradation activities on tetracyclines by hydroxylation at C11a and were multidrug-resistant to tigecycline, tetracycline, florfenicol, ciprofloxacin and trimethoprim/sulfamethoxazole. Genetically, they belonged to two sequence types (ST355, n = 8; ST1980, n = 2) that were consistent with their pulsotypes, revealing a clonal spread of ST355 A. baumannii. An IS CR2 - or IS 26 -mediated tet (X) transposition structure, homologous to those of clinical A. baumannii strains, was also identified and IS CR2 could transfer tet (X5) into the recipient Acinetobacter baylyi ADP1 at a frequency of (1.8 ± 0.3)×10−6. Therefore, more efforts are needed to evaluate the clinical impact of these tigecycline resistance genes. [ABSTRACT FROM AUTHOR]

Improving the photo-induced hot charge utilization rate in granular catalysts with specific nanostructure is hindered by limited hot electron production and rapid recombination in plasmonic metal particles; therefore, promoting photo-induced hot charge generation and transfer during the plasmonic process is a vital approach for enhancing plasmonic catalytic performance. In this work, with the intention of constructing Pd-tipped Au nanorod heterostructures to achieve plasmon-enhanced formic acid dehydrogenation, the magnetic-field-derived electromagnetic induction effect is utilized to further boost the generation and transfer of plasmonic hot charges in Au nanorods. By exposing the plasmonic catalytic system to a rotating permanent magnet at 28 °C, formic acid dehydrogenation efficiency was improved by approximately 60%. The improvement rate in the same system can exceed 150% at 45 °C. This enhancement is attributed to the increase in plasmonic hot charges and the suppression of charge recombination based on the electromagnetic induction effect of plasmonic Au nanorods in a rotating magnetic field. This work provides a practical strategy for designing high-activity catalysts regulated via magnetic field for formic acid dehydrogenation. ga1 • The magnetic-field is utilized to further boost the plasmonic hot charge generation and transfer from Au nanorods to Pd. • The formic acid dehydrogenation efficiency were improved 60% and 150% at 28 °C and 45 °C in rotatingmagnetic field. • The increase in plasmonic hot charges and the suppression of charge recombination by the electromagnetic induction effect. [ABSTRACT FROM AUTHOR]

Selective and sensitive detection of heavy metal ions is a theme of increasing scientific interest, great technological importance and extensive public concern. To realize this target, design of high-efficient and fluorescent materials as sensor is crucial yet challenging task. In this work, we describes the synthesis and functions of a new hydroxyl and imine groups functionalized covalent organic framework (COFs). The synthesized COFs-DT integrates multi-functionality such as extended π-conjugation framework, tunable functionality, regular pore structure, specific sites to interact with targets as well as robust chemical and thermal stability. COFs-DT shows strong and stable fluorescence when dispersed in isopropanol. The fluorescent property together with the unique bidentate ligand sites enables COFs-DT in the construction of a high-performance fluorescent sensor for detection of Cu2+ with high sensitivity and selectivity. Furthermore, we use a series of characterizations to investigate the fluorescence quenching mechanism and found the quenching through a photoinduced electron transfer mechanism with COFs-DT as donor and Cu2+ as acceptor. Our strategy not only highlights opportunities for utilizing COFs with integrated multiple unique nature as new type of fluorescent materials, but also expends the encapsulation scope of COFs for ion sensor in environmental field. A hydroxyl and imine groups functionalized covalent organic framework with strong and stable fluorescence in isopropanol was utilized to construct a fluorescent sensor for Cu2+ detection with high sensitivity and selectivity. Image 1 • A novel hydroxyl and imine groups functionalized covalent organic framework (COF) is designed and prepared. [ABSTRACT FROM AUTHOR]