Abstract:As an important organic nitrogen-containing intermediate, imines are widely used in the fields of pharmaceuticals and fine chemical synthesis. In recent years, the catalyst preparation of this process has been a research highlight, and researchers have developed many efficient and low-cost catalysts for catalyzing the synthesis of imines. This paper provides a comprehensive review of catalysts for the synthesis of imines by oxidation of alcohol amine and coupling reaction of primary amine, and briefly introduces the homogeneous catalysts. The performance and catalytic mechanism of heterogeneous catalysts are discussed in detail from the viewpoint of oxide catalysts, supported catalysts and other types of catalysts. The performance regulation of homogeneous catalysts and heterogeneous catalysts is briefly summarized. Finally, the potential opportunities and challenges of this research are discussed, in order to provide reference for the future controllable preparation of novel and high-performance synthetic imide catalysts.

Abstract:As a core component of electrochemical energy conversion devices, the performance improvement of polymer anion exchange membranes is one of great significance for advancing new energy technologies. This review summarizes the main challenges faced by the application of anion exchange membranes, particularly the low ionic conductivity and poor stability. To delve into the root causes of these issues, the mechanisms of ion transport and chemical degradation are analyzed at the molecular structure level, and the strategies for improvement are further summarized from the three dimensions: ion group, main chain structure, the aggregated state structure. Next, the strategies employed by researchers to achieve high ionic conductivity and stability in anion exchange membranes are summarized from three aspects: ionic groups, polymer backbones, and the microscopic microphase separation of the membranes. Key factors influencing the performance of anion exchange membranes are also analyzed. Subsequently, the key factors to enhance the performance of anion exchange membranes are summarized. Next, the latest progress in the application of anion exchange membranes in electrochemical energy conversion, such as fuel cells, water electrolysis, CO2 reduction reaction, flow batteries, etc is reviewed. Finally the future research directions of anion exchange membranes are prospected, providing guidelines for their design toward the large-scale commercial applications.

Abstract:Conjugated microporous polymers (CMPs) are an advanced organic porous material class combining π-π conjugated electronic systems with well-defined microporous structures. Owing to their unique physicochemical properties, CMPs have garnered significant attention in recent years and have been widely applied in gas adsorption, membrane separation, catalysis, energy storage, and flame retardancy. Since their initial discovery, CMPs have remained a focal point of research. Their distinctive pore structures and surface properties have made them increasingly attractive for photocatalytic applications. This review provides a concise overview of the photocatalytic mechanisms of CMPs, followed by a discussion of strategies to enhance their photocatalytic performance. These include the design of donor-acceptor (D-A) structures, heteroatom doping, selecting appropriate monomers, and optimizing synthetic methodologies. The applications of CMPs in photocatalysis are then summarized, focusing on photocatalytic hydrogen evolution, CO? reduction, and organic synthesis. Finally, future research directions are proposed. In addition to further improving the photocatalytic efficiency of CMPs, efforts should be directed toward addressing challenges in large-scale production, particularly in designing viable technological routes. Key areas of focus should include the development of Schiff-base and other non-noble metal coupling reactions, achieving a balanced integration of high surface area, electrical conductivity, and mechanical strength, constructing theoretical models to elucidate structure-property relationships in microporous materials, and leveraging quantum chemistry and artificial intelligence to optimize material design strategies. Key words: conjugated microporous polymers; photocatalysis; photocatalytic hydrogen production; CO2 reduction; organic synthesis

Abstract:L-ascorbic acid-salicylic acid ester (LOHB) was synthesized by the chloride method using L-ascorbic acid (LA) with excellent antioxidant ability and salicylic acid (SA) with good UV absorption ability as raw materials, which possesses the properties of each of the two. The DPPH radical scavenging rate of LOHB has reached 90% at 40ug/ml, and the absorption of UVB, UVC and UVB has been realized at 0.5mg/ml. UVB and UVC absorption. LOHB was added to gelatin solution, and the composite film was prepared by casting, and its antioxidant and UV resistance was significantly improved, and the DPPH radical scavenging rate was 62%, as well as the absorption of UVB and UVC had been achieved. Corn alcohol soluble protein and rosin were laminated with the composite film to improve the moisture resistance of the monolayer film, and the moisture absorption rate decreased from 95% to 40%. At the same time, the performance of the constructed bilayer film was further improved, with a free radical scavenging rate of more than 90% as well as partial absorption of UVA on top of the monolayer film, further expanding the potential application range of the film.

Abstract:This study presents the development of a new, convenient and cost-effective fluorescent probe for detecting pesticide glyphosate residues in agricultural products. By using 3,4,9,10-perylenetetracarboxylic acid (PTCA) as a ligand to form a complex with divalent copper ions (Cu₂₊^{), a fluorescent probe based on the PTCA} and Cu₂₊ ^{complex ([PTCA+Cu₂₊}]) was successfully constructed. The [PTCA+Cu^₂₊] probe exhibits specific recognition capability for glyphosate, with a detection limit of 0.028 μg/mL. Experimental results from fluorescence spectroscopy, UV-Vis absorption spectroscopy, Job"s Plot analysis, and infrared absorption spectroscopy demonstrate that the probe offers rapid and accurate detection performance for glyphosate. The recognition mechanism of the probe for glyphosate detection was also explored. Spike recovery experiments on the vegetable brassica campestris confirmed the feasibility of the probe in practical applications. Furthermore, the study extended to the development of fluorescent test strips using this probe system, which holds promise as a convenient visual monitoring tool for on-site glyphosate detection in real samples. This research provides a novel, convenient, and sensitive analytical method for glyphosate detection, offering significant application value.

Abstract:Intermolecular aggregate and regulation of small-molecule acceptors (SMAs) are crucial for photovoltaic performance of organic solar cells (OSCs). In order to investigate the relationships between chemical structures and molecular aggregation, photovoltaic performance, SMA CA2F-M6 based on carbazole with macrocyclic sidechain has been developed. CA2F-BO without macrocyclic sidechain has been synthesized as a comparison. These SMAs have shown similar solubilities in spite of different alkyl sidechains, due to the strong intermolecular aggregation has been suppressed by macrocyclic sidechain. Compared with CA2F-BO, CA2F-M6 exhibits blue-shift absorption in solution, because CA2F-M6 with macrocyclic sidechain shows the larger dihedral angle. CA2F-BO and CA2F-M6 have similar optical bandgap of 1.77 eV, and indicated that they possess similar molecular configuration in thin films. Both of them also show suitable highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels with polymer donor PM6. As a result, OSC based on PM6:CA2F-BO exhibit a power conversion efficiency (PCE) of 2.85%. Meanwhile, PM6:CA2F-M6 cell achieves much better PCE of 3.93% with enhanced short-circuit current and fill factor. Further, ternary OSC based on PM6:CA2F-M6:L8-BO has been fabricated and exhibits a promising PCE of 17.61%.

Abstract:Tetranitro intermediates were synthesized from 2,2"-biphenyldicarboxylic acid and reduced with iron powder to obtain diamine compounds with a heteropyrene structure. The corresponding black polyimide (PI) films were then synthesized via the “two-step” method. GPC results showed that the number average molecular weights of the polyamic acids ranged from 9.9×10₄ ^{to 12.9×10}₄^{, sufficient for the formation} of self-standing film. FTIR-ATR spectra revealed characteristic peaks of the imide ring at 1784 cm_-1 ^{and 1722 cm}_-1^, confirming successful preparation of the PI films. CIE Lab analysis demonstrated that the transmittance of these PI films ranged from 1.10% to 3.17% between 400 nm and 750 nm, with L* values between 9.79 and 21.08, classifying the films as black. The glass transition temperature (T_g) of the PI films exceeded 413 °C, with PI-3 (polymerized with BPDA) reaching 482 °C. The 5% decomposition temperature was above 557 °C, while the CTE values ranged from 9.92 ppm/K to 0.47 ppm/K between 50 °C and 350 °C , indicating excellent thermal properties. The PI films also exhibited good mechanical properties, with tensile strength ranging from of 132.1 Mpa to 156.5 MPa, tensile modulus of 4.4 Gpa to 5.3 GPa, and elongation at break values between 3.33% and 5.14%.

Abstract:A novel Cu-doped carbon dots (Cu-CDs) was prepared by simple and eco-friendly one-step hydrothermal method using the natural Astragalus polysaccharides as carbon source and Cu2+ as doping agent. A series of characterization methods (UV-vis, FL, FTIR, TEM and XPS, etc) were used to characterized the optical properties, surface functional groups, morphology and elemental composition of Cu-CDs. The fluorescence quantum yield of Cu-CDs is 22.4% and displayed green fluorescence under 365 nm UV light. L929 cells co-cultured with 200 μg/mL Cu-CDs not only did not show significant cytotoxicity, but also favored cell proliferation. In addition, the hemolysis rate of Cu-CDs for rabbit blood in the concentration range of 0~800 μg/mL is lower than GB/T standard 5%, that is, Cu-CDs has good biocompatibility. Antibacterial results showed that, compared with APS-Cu complexs, Cu-CDs improved the antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), also exhibited better inhibitory activity against Aspergillus flavus (A. flavus) and Aspergillus niger (A. niger). The MIC values of Cu-CDs for the above strains were 60, 100, 125 and 40 μg/mL, respectively. Meanwhile, the antioxidant activity of Cu-CDs was evaluated by the clearance rates of DDPH·, ABTS·+ and OH·. The results showed that the IC50 values of Cu-CDs against DDPH·, ABTS·+ and OH· were 48.6, 6.4 and 3.8 μg/mL, which were much lower than those of pure APS and APS-Cu. In summary, a high biocompatibility, strong antimicrobial and antioxidant activity Cu-CDs based on natural Astragalus polysaccharides and Cu2+ was developed, that offering promising insight into the development of novel antimicrobial and antioxidant agents in biomedical materials and food industry.

Abstract:Dental caries, recognized as one of the most prevalent oral diseases, exhibits a strong correlation with Streptococcus mutans. Manganese tungstate (MnWO_x) nanoparticles enriched with oxygen vacancies were synthesized via an organic phase method followed by calcination. The morphology and structure of MnWO_x nanoparticles before and after calcination were thoroughly characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results revealed that MnWO_x calcined at 400 °C for 1 hour possessed the highest proportion of oxygen vacancies while maintaining a similar morphology compared with uncalcined sample. Probe tests were employed to assess the ability of MnWO_x in generating ₁^O₂ and .OH radicals after ultrasonic activation, demonstrating that an increase in oxygen vacancies significantly enhanced the radical-generating capacity of MnWO_x. Antibacterial experiments demonstrated that MnWO_x-PEG under 5 minutes of ultrasonic exposure could eliminate 70.57% of Streptococcus mutans, while MnWO_x-PEG under 10 minutes of ultrasonic exposure could eradicate 80.57% of Streptococcus mutans within a biofilm. These findings suggest that the sonodynamic approach for oral antibacterial and anti-biofilm treatment offers a novel and promising strategy for the prevention of dental caries and the promotion of oral health.

Abstract:Hollow spherical aminofullerene aggregates encapsulating L-cysteine (L-Cys@NFH) were prepared by ethylenediamine (EDA) modification followed by liquid-liquid interfacial precipitation (LLIP) method. The composition, microstructure, and particle size distribution of L-Cys@NFH were characterized using FTIR, XPS, EA, SEM, TEM and EDS. The biocompatibility and cell migration ability of L-Cys@NFH on human gastric mucosal cells (GES-1) were investigated based on cytotoxicity tests and in vitro scratch assays. The protective performance of L-Cys@NFH on GES-1 cells was evaluated using a hydrogen peroxide (H2O2)-induced oxidative stress model. Experimental results showed that L-Cys@NFH exhibited monodisperse properties with an average particle size of 553 nm and an average wall thickness of 123 nm. At 200 μg/mL, the DPPH radical scavenging rate of L-Cys@NFH exceeded 85%, and the ·OH scavenging rate was 66.1%. L-Cys@NFH showed no significant cytotoxicity at concentrations of 12.5~200 μg/mL. The scratch closure rate of GES-1 cells treated with 50 μg/mL L-Cys@NFH reached 82%. L-Cys@NFH protected GES-1 cells against reactive oxygen species (ROS) and prevented H2O2-induced cellular damage, with a cell survival rate of 100% at 50 μg/mL.

Abstract:In order to improve the conductivity and reversibility of molybdenum trioxide (MoO3), MoO3@MoS2 composites were prepared by direct anion exchange reaction.The optimum conditions were obtained: n(Mo): n(S)= 1:1, 180 ℃ for 24 h, by orthogonal experiments.The morphology and structure of MoO3@MoS2 was characterized by XRD, SEM, HRTEM, Raman, XPS and EPR.The results show that MoS2 is uniformly grown on the one-dimensional MoO3 nanorods after modification, which makes the surface of the material rough and increasing the specific surface area. The crystalline of the material changed from α phase to h phase, and presents amorphous, with a large number of oxygen vacancies. Electrochemical tests show that MoO3@MoS2 exhibits excellent kinetic behaviors. After thiourea modification, MoO3@MoS2 increases the contribution of pseudocapacitance. The results of GITT test show that the diffusion coefficient of MoO3@MoS2 ranges from 10-10 to 10-13 cm2/s, which is significantly higher than that of MoO3.At the current density of 0.1A/g, MoO3@MoS2 has a specific discharge capacity of 68.42mAh/g, about twice that of MoO3 (33.51mAh/g), and exhibits excellent rate performance and favorable cycle stability, maintain a capacity retention of 90% after 100 cycles.

Abstract:Saffron (Crocus sativus. L), also known as crocus and saffron, is the dried stigma of saffron in the family Iridaceae. Although the small-sized stigma is the traditional medicinal and culinary part of saffron, the large-petaled inflorescences, which make up more than half of the plant"s biomass, have traditionally been wasted as biowaste. Notably, the petals have been proven to be rich in flavonoids, polyphenols and other active substances. Therefore, the development and utilization of saffron petals can not only avoid the waste of resources, but also create new product values. In this study, the aroma profile of saffron petals was constructed by sensory analysis, and it was found to be mainly floral, sour, sweet, roasted and powdery. Subsequently, the volatile components were extracted by solid-phase microextraction (SPME) combined with solvent-assisted flavor evaporation (SAFE), and their flavor components were systematically analyzed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O), and ultimately, 29 volatile constituents, including 6 aldehydes, 6 alcohols, 6 acids, 3 ketones and 1 ester were identified, 2 terpenoids, 4 heterocyclic, and 1 other. Among them, the higher contents were heterocyclic (mean 3.782 μg/g), alcohol (mean 1.421 μg/g) and acid (mean 1.405 μg/g) compounds. Based on the Aroma Extract Dilution Analysis (AEDA), two key aroma substances, phenylethanol (FD value = 27) and phenethyl acetate (FD value = 27), were further screened, and their contributions were highly consistent with the results of sensory evaluation. The results can provide data support for the flavor composition and deep processing of saffron petals.

Abstract:The development of highly efficient catalysts is the core of promoting the application of amborane (AB, NH3BH3) as a hydrogen storage material, aiming to improve the reaction rate (kinetics) and energy efficiency (thermodynamics) during its hydrolysis to hydrogen. ZIF-67 modified P25 composite carrier was firstly prepared, and trace amounts of Ru was evenly dispersed on the above carrier using the deposition precipitation method. Finally, RuCo/P25-NC catalyst was obtained by calcination and reduction and its catalytic performance for ammonia-borane hydrolysis was investigated. The results showed that the catalytic activity of RuCo/P25-NC was much higher than that of Ru/P25 and RuCo/NC catalysts, and the turnover frequency (TOF) of RuCo/P25-NC at 303 K was 1072.6 min?1, which was 6.0 and 4.8 times as high as that of Ru/P25 and RuCo/NC, respectively. The reaction activation energy (Ea) of RuCo/P25-NC was 35.6 kJ·mol?1. In addition, when the reduction temperature was 350 ℃ and the mass fraction of Ru loading was 0.3%, RuCo/P25-NC catalyst has the highest activity. The RuCo/P25-NC catalyst has good cycling stability with high TOF even after six cycles.

Abstract:The N-doped active carbon prepared by high-temperature carbonization of Cyanobacterial blooms (CBB) is used to aerobic oxidation of 5-hydroxymethylfurfural (HMF), thus developing a green catalytic technology for 2,5-diformylfuran (DFF) synthesis, while disposing cyanobacterial blooms as a resource. The prepared N-doped active carbon（N-AC-CB）was characterized by XRD、Raman、BET、XPS and FT-IR methods, and used as a catalyst for aerobic oxidation of HMF to DFF. The effects of carbonization temperature of CBB and reaction conditions on the reaction were investigated. The results show that: the N-AC-CB-700 obtained by carbonization of CBB at 700℃has good catalytic performance, and the graphite- type nitrogen hybrid structure contained in it plays an important role in the formation of catalytic active centers; Under the catalytic action of N-AC-CB-700, 92.8% yield of DFF was achieved with HMF complete conversion. After the catalyst reused 7 times, the activity only decreased by 5.4%, and after reused 9 times, the activity decreased by 13.3%.

Abstract:HZSM-5 with different silica-to-aluminum ratios was prepared by a hydrothermal method by post-grafting 3-mercaptopropyltrimethoxysilane (MPTS) and oxidized with aqueous H2O2 to generate a solid acid catalyst (SO3H-HZSM-5). It was characterized and analyzed by XRD, FT-TR, Raman, XPS, EDS, Py-IR and NH3-TPD, and used for the degradation of waste polyethylene terephthalate (PET) fibers in a neutral hydrolysis system.The optimal reaction conditions for PET hydrolysis by the catalyst were investigated. In addition, the reaction kinetics and mechanism of SO3H-HZSM-5 catalyzed hydrolysis of PET ?were thoroughly investigated, and the recycling performance of the solid acid catalyst was evaluated. The results showed that the Br?nsted acid (B acid) quantity of HZSM-5 modified by sulfonation with a silica to aluminum ratio of 50 was significantly enhanced, and the linear positive correlation between the B acid amount and the catalytic activity was experimentally demonstrated; under the optimum reaction conditions of reaction temperature 200 ℃, reaction time 13 h, catalyst 2 g, and m(PET): m(H2O)=1: 10, the PET conversion and terephthalic acid (TPA) yield were 99.72% and 94.42%, respectively; the activation energy of SO3H-HZSM-5 for catalytic hydrolysis of PET was 96.57 KJ/mol; SO3H-HZSM-5 can still reach 98.08% and 93.26% of PET conversion and TPA yield after 4 times of recycling.

Abstract:The catalytic hydrogenation of furfural to furfuryl alcohol is a crucial process for the value-added conversion of biomass-based furan derivatives. In this study, three types of alumina catalysts with varying mass ratios of Si and P were selected. The structural and acid-base properties of these catalysts were characterized using techniques such as XRD, SEM, EDS, N2 adsorption-desorption, Py-FTIR, NH3-TPD, and CO2-TPD. The effects of the acid-base properties of the alumina, reaction temperature, and catalyst dosage on the conversion rate of furfural and the selectivity of furfuryl alcohol were investigated. The results indicate that the three alumina catalysts have the same crystal structure and similar textural properties, but exhibit significant differences in their acid-base properties. Among them, the B-Al2O3 catalyst, with moderate Lewis (L) acid sites, base sites, and intermediate Si and P mass fractions, exhibited the best catalytic performance. In the transfer hydrogenation of furfural to furfuryl alcohol, the synergistic effect between Lewis acidic sites and basic sites was found to the enhance both the conversion rate of and the selectivity of furfuryl alcohol. Under the conditions of a reaction temperature of 160 °C, reaction time of 2 h, catalyst dosage of 300 mg, and the furfural dosage of 3 mmol, B-Al2O3 can achieve a furfural conversion rate and furfuryl alcohol selectivity both exceeding 99%. The catalyst exhibited good stability and could be reused after simple calcination. At the fifth reuse, the conversion rate of furfural was 96.1% and the selectivity of furfuryl alcohol was 94.3%.

Abstract:By loading three representative Br?nsted acids (sulfuric acid, 4-aminobenzenesulfonic acid and phosphotungstic acid) onto the two carrier materials of biochar support, derived from rice straw and glucose, respectively, seven solid acid catalysts with distinct biochar carriers and physicochemical properties were prepared, which included RSCA, SO42-/ZrO2/RSC600, SO42-/ZrO2-TiO2/RSC600, SO42-/ZrO2-TiO2/GC600, SO42-/ZrO2-TiO2/C3N5, HPW/RSC and ABS/RSC. The catalysts were applied to the hydration reaction of α-pinene. The structural composition and pore structure of the seven solid acid catalysts were characterized by FTIR, XRD and BET analyses. Hydrophobicity and total acid strength/acidity were measured by water contact angle analysis and acid-base back titration. The effects of the physicochemical properties of solid acid catalysts and solvent types on the catalytic activity were evaluated by monitoring the conversion of α-pinene and the selectivity of α-terpineol in the hydration reaction.The results demonstrated that, compared to porosity, acidity and excessively strong acid strength, the key factors promoting the selective conversion of α-pinene to α-terpineol were the abundant oxygen-containing functional groups, moderate acid strength (Hammett constant < 0), and weak hydrophilicity (water contact angle > 60°) of the prepared solid acid catalysts. Under the conditions of 80 °C for 24 h, when the straw-derived biochar-based solid acid or the straw-derived biochar-supported phosphotungstic-acid solid acid was used as the catalyst, the conversion of α-pinene and the selectivity of α-terpineol exceeded 85.00% and 25.00%, respectively. Acetone, as a medium-polarity non-alcoholic solvent, stabilized the pinanyl carbocation via its oxygen-containing functional groups, consequently improving the catalytic performance of the catalysts.

Abstract:Self-assembly between Cu(II) and photoredox 4,4"-(anthracene-9,10-diyl)dibenzoic acid constructs a new 2D metal organic framework Cu–ADBA with photoinduced LMCT (Ligand-to-Metal Charge Transfer) behavior using solvothermal method, and the crystal structure has been characterized by single-crystal diffraction and PXRD. SEM, TEM, and AFM measurements indicate that Cu–ADBA in solution can be exfoliated and form nanosheets with 4nm thickness, which is favorable to expose more catalytic sites. UV-Vis showed that the ligand H2ADBA has a wide absorption band between 350 and 410 nm, the excited state reduction potential of H2ADBA was -1.56 V (vs. Ag/AgCl), which is able to reduce Cu(II) in the metal node of Cu–ADBA. The fluorescence spectrum shows that the fluorescence intensity of Cu–ADBA is much smaller than that of the ligand, and the Raman spectrum, XPS photoelectron spectra and EPR spectra show that the ligand in MOF was excited under the illumination, which reduces the Cu(II) in the metal node to Cu(I). Under 365 nm LED light, the cycloaddition click reaction of alkynes and benzyl azides was efficiently catalyzed by Cu–ADBA with glucose as the electron-sacrificing agent, and the catalysts could be reused for three times without obvious deactivation.

Abstract:Based on the structure of N523 amide extractant, six new types of amides extractants have been designed and synthetized, including mono-amide, bis-amide and 3-oxopentanediamide, then have been applied to the study of the performance of extraction of lithium from brines of salt lakes with high magnesium-lithium ratios. Firstly, the structures of six new amide extractants were synthesized and characterized. Secondly, the extraction conditions of N523 amide extractant in brine with high magnesium-lithium ratio (magnesium-lithium ratio of 236) were explored, including parameters such as brine acidity, iron-lithium ratio, extraction phase ratio, and extractant concentration. As a result, the single-stage Li+ extraction rate of the optimized N523 extractant reached over 77%, and the lithium-magnesium separation factor was as high as over 4800. Subsequently, the lithium-magnesium separation performance of the three newly synthesized types of six amide extractants in brine with high magnesium-lithium ratio was discussed. Among them, the monoamide extractant exhibited excellent lithium-magnesium separation effect, while the diamido and 3-oxopentanedioic diamide extractants showed poor lithium-magnesium separation effects. DFT theoretical calculation and analysis indicated that the lithium-magnesium separation abilities of different types of amide extractants followed the order: monoamide > 3-oxopentanediamide > diamido. This difference was caused by the combined influence of the electrostatic potential energy and steric hindrance of the molecules themselves. The theoretical analysis was basically consistent with the experimental results.

Abstract:A series of Mg-Al binary composite oxide catalysts (MMO) were synthesized via the co-precipitation method using ammonia as the precipitant, magnesium nitrate as the magnesium source, and aluminum nitrate as the aluminum source. The microstructure and surface properties of MMO were characterized by XRD, XPS, TEM, EDS, and BET analysis. The effects of the Mg/Al molar ratio, reaction temperature, reaction time, and catalyst dosage on the yield of isophorone were systematically investigated. The results demonstrated that co-Mg2.5Al1-MMO-2, prepared with an Mg/Al molar ratio of 2.5:1, exhibited the highest catalytic activity for isophorone synthesis via acetone condensation. The optimal reaction conditions were determined to be: reaction temperature of 200 ℃, reaction time of 8 h, and a catalyst loading of 5.9%. Under these conditions, the selectivity of isophorone reached 47.27%, with a yield of 40.74%. co-Mg2.5Al1-MMO-2 possesses a mesoporous structure, functions as an acid-base synergistic catalyst, and contains medium-strength basic sites along with a high proportion of strong acidic sites (74.05%), which are beneficial for isophorone formation. Furthermore, the catalyst still has good catalytic properties under amplification conditions, with the selectivity of isophorone reaching 42.88% and the yield is 38.29%.

Abstract:To explore the green synthesis process of isomeric fatty acid esters and reveal the relationship between the physical chemistry properties of oils and their effects on skin. A series of isomeric fatty acid esters were synthesized by solvent-free method using isomeric fatty alcohols and 3,5,5-trimethylhexanoic acid as raw materials, p-toluenesulfonic acid and phosphorous acid (molar ratio 3.05:1) as composite catalysts. The synthesis conditions of model compound isononyl isononanoate (ININ) were optimized by single factor and response surface methodology. The structure of ININ was confirmed by FTIR and 1H NMR. The physical chemistry parameters such as surface interfacial tension, contact angle, diffusion coefficient, friction coefficient and compatibility were determined. The effect of the structure of isomeric fatty acid esters on its wetting, spreading, moistening and cleaning ability was investigated. The results showed that the optimum conditions for the synthesis of ININ were as follows: the amount of catalyst (mass percentage of isononanoic acid) was 1.44%, the conversion of isononanoic acid was 97.17% when the molar ratio of isononyl alcohol to isononanoic acid was 1.16:1.0, reaction temperature was 130.5 ℃ and reaction time was 3.73 h. The synthetic esters were colorless, transparent and odorless, and the conversions of fatty acids were more than 95%. The surface tension of polymethyl branched isomeric fatty acid esters ININ and isotridecyl isononanoate (INIT) was less than 30 mN/m, the contact angle was less than 50°, and the diffusion rate was about 40 mm/s, which had good compatibility with makeup ingredients, can spontaneously spread out on the skin. Freshness and cleanliness superior to traditional mineral oils and linear fatty acid esters. When 8 kinds of fatty acid esters were applied to the skin, the static friction coefficient and dynamic friction coefficient were reduced by more than 59% and 60%, respectively. Isononanoic acid 2-hexyl decanol ester has a relatively symmetrical number of hydrophobic chains and better wettability.

Abstract:In order to explore the anti-oxidative stress activity and mechanism of the compound of alfalfa and hawthorn leaf extract, alfalfa extract (ME), hawthorn leaf extract (HE) and their compound (ME+HE) with mass ratio of 6:4 were used as the research objects. The contents of total flavonoids, total triterpenoid saponins and total polysaccharides in ME, HE and ME+HE were determined by ultraviolet spectrophotometry. The antioxidant activities of ME, HE and ME+HE in vitro were evaluated by free radical scavenging experiment, total reduction ability determination and intracellular reactive oxygen species (ROS) scavenging experiment. The anti-oxidative stress mechanism of ME+HE was explored by Western Blot. The results showed that the contents of total flavonoids in ME, HE and ME+HE were 3.60%±0.10%, 14.12%±2.73% and 7.13%±1.55%, respectively. The mass fractions of total triterpenoid saponins were 1.90%±0.15%, 4.08%±1.17% and 2.85%±0.50%, respectively. The contents of total polysaccharides were 12.38%±4.75%, 26.27%±0.73% and 18.37%±1.83%, respectively. ME+HE with a mass concentration of 5 mg/mL had good 2,2"-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium cation (ATBS+), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and hydroxyl radical scavenging ability. The scavenging rates were 97.15%, 92.74%, and 76.00%, respectively. The total reduction ability was 75.51% higher than that of ME. ME+HE could significantly remove excessive ROS in cells, and the inhibitory ability was better than that of ME and HE alone. In the Western Blot experiment, the expression of nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) protein in HepG2 cells was down-regulated after oleic acid (OA) induction. After treatment with different doses (0.9375, 1.875, 3.75 mg/mL) of ME+HE, the expression levels of Nrf2 and HO-1 proteins were up-regulated. The expression of Nrf2 protein increased by 10.5%, 48.9% and 53.3%, respectively, and the expression of HO-1 protein increased by 72.0%, 82.0% and 85.3%, respectively. It showed a dose-dependent. ME+HE can improve antioxidant capacity through Nrf2/HO-1 signaling and play an anti-oxidative stress role.

Abstract:To investigate the performance and preservation effect of a new formulation of 1-methylcyclopropene (1-MCP), stable 1-MCP inclusion complexes of water in oil (W/O) were prepared by emulsifying soybean oil and liquid paraffin containing emulsifiers using a water-based dispersion of 1-MCP solid inclusion complex. Then, the water in oil in water emulsification pathway was used to disperse the water in oil (W/O/W) type 1-MCP inclusion complex in the water phase, effectively releasing the effective preservative components of 1-MCP embedded in it. Using GC/MS testing technology to characterize the components and release rates of gases released from 1-MCP inclusion complexes, in order to determine the release rates of 1-MCP components in different formulations of inclusion complexes, and the 1-MCP in W/O and W/O/W preservatives can be continuously released for more than 20 days. At the same time, using Hutai No. 8 grape as the test material, the preservation effect of the W/O/W type 1-MCP inclusion compound on grape fruits was studied. The results showed that both inclusion compounds had a certain regulatory effect on the preservation of Hutai No. 8 grape, effectively inhibiting their maturation, dehydration, decay, and mold growth during storage, ultimately extending the storage period of grape by 20 days. The research results provide certain technical support for expanding the usage methods and application scope of 1-MCP preservative.

Abstract:Double-bonded dopamine (DMA) was prepared by amidation reaction using dopamine hydrochloride containing catechol structure and methacrylic anhydride as raw materials. The DMA was subjected to radical polymerization with methyl methacrylate (MMA) and butyl acrylate (BA) to prepare a dry and wet rubbing fastness resistant polyacrylate film-forming agent (PA-DMA). The structure of PA-DMA was characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (1H-NMR), ultraviolet-visible spectroscopy (UV-vis) and gel permeation chromatography (GPC). The results showed that PA-DMA was successfully prepared. PA-DMA was applied in leather finishing process. The application results show that the wet rub resistance of the bionic polyacrylate film-forming agent is higher than that of the pure polyacrylate film-forming agent and the commercially available polyacrylate film-forming agent, which can be improved by level 2 and level 1, respectively. The dry rub performance was improved by level 2-3 and level 1 respectively. This indicated that the both the dry and wet rubbing fastness of the the dry and wet rubbing fastness resistant polyacrylate film-forming agent finished leather has been significantly improved.

Abstract:The disordered link polymer chain (Nim(Mo3S11)n) was grown on carbon cloth (CC) surfaces by coordinating [Mo3S13]2- clusters and Ni2+ ions. The abundant sulfur active sites of the catalyst provide more active centers for efficient activating persulfate (PMS) to degrade tetracycline (TC). Nim(Mo3S11)n-CC was thoroughly characterized by SEM, TEM, XRD, Raman and XPS. The influence of various reaction systems, catalyst loadings, PMS dosages, pH values, common anions (Br-, Cl-, HCO32-, HPO42-) and various water sources were systematically investigated. The mechanism underlying PMS activation by Nim(Mo3S11)n-CC-Light was elucidated through radical quenching experiments and EPR spectroscopy. The experimental results showed that Nim(Mo3S11)n-CC+PMS-Light system reached 97.50% degradation of TC within 60 min. The optimal experimental conditions were determined to be a catalyst ratio of 5:1, PMS concentration of 0.3 g/L, and pH = 7. The presence of different anions exhibited varying degrees of inhibition on TC degradation, while the TC degradation rate exceeded 85% in all water sources tested. After five cycles of experimentation, the degradation rate of the Nim(Mo3S11)n-CC+PMS-Light system remained above 90%. The mechanism of TC removal by Nim(Mo3S11)n-CC-Light involves the primary roles of O2·- and 1O2, while SO4·-and ·OH play secondary roles.

Abstract:CO2 enhanced oil recovery (CO2-EOR) technology not only can improve oil recovery, but also can reduce emissions. However, due to the large viscosity difference between oil and CO2, gas channeling occurs easily during CO2-EOR, using CO2 thickeners can effectively solve this problem. But, the existing CO2 thickeners unable to satisfy the requirements of CO2 flooding in the eastern South China Sea oilfield. In this work, a thickener MSVA for CO2 flooding that suitable for medium-high temperature reservoirs was prepared by using AMPS, styrene, maleic anhydride and vinyl acetate as raw materials. The molecular structure and synthesis conditions of the thickener were optimized, and then the thickening, solubility and oil displacement effect of the thickener were evaluated. The results showed that the formula of thickener is : AMPS : styrene : maleic anhydride : vinyl acetate molar ratio = 1:1:4:3, and the optimum synthesis conditions are temperature 80 ℃and initiator dosage 0.1 g. The thickener MSVA can effectively increase the viscosity of CO2 at 80 ℃, 15 MPa and weight fraction of 2%, the viscosity of thickened CO2 reached 1.04 mPa·s, and it can be completely dissolved in CO2 within 27 min. Moreover, compared with the pure CO2 flooding after water flooding under the same conditions, the viscous CO2 flooding after water flooding can increase the oil recovery rate by 6.92 %.