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Three new compounds (1‒3), including a phenylpropanoid (1), a bistetrahydrofuran lignin (2), and a lignan dimer (3), and seven known lignans (4‒10), were isolated from an EtOH extract of the aerial parts of Triadica rotundifolia. The structures of the new compounds were elucidated by comprehensive spectroscopic analyses. New compounds 1−3 were evaluated for their antineuroinflammatory and antioxidant activities. Research on the antineuroinflammatory activity suggested that compounds 2 and 3 had significant inhibitory effects on NO production in LPS-induced BV-2 cells, with the IC50 values of 15.7 and 5.8 μM, respectively. Meanwhile, compounds 2 and 3 exhibited better DPPH free radical scavenging activities with EC50 values of 2.0 and 4.3 μM, respectively, than the positive control vitamin C (EC50 = 14.3 μM).

Three new tyramine-type alkamides (1-3), three new natural products (4-6), five new N-acylated/formylated aporphine alkamides with different ratios of rotational isomers (7-11), and 20 known alkamides (12-31) were isolated from an EtOH extract of the stems and leaves of Piper puberulum. The absolute configurations of compounds 7, 8, and 10 were determined by single-crystal X-ray diffraction analysis. In the biological activity assay, compounds 3, 5, and 10-23 displayed inhibitory effects against lipopolysaccharide-induced NO release in BV-2 microglial cells, exhibiting IC50 values of 0.93-45 μM.

Three new pairs of lignan enantiomers (1a/1b‒3a/3b) and two pairs of known lignan enantiomers (4a/4b and 5a/5b) were isolated from the stems of Mappianthus iodoides. The structures of the enantiomers were elucidated by comprehensive spectroscopic analyses. Their absolute configurations were assigned by single-crystal X-ray diffraction analysis as well as comparison of the experimental and calculated ECD spectra. The antineuroinflammatory activity research revealed that compounds 2a, 2b, 3a, 4a, and 5b could moderately inhibit NO production in LPS-induced BV-2 microglial cells with IC50 values ranging from 13.42 to 48.34 μM.

Two pairs of cycloneolignane enantiomers, piperhancins A and B (1 and 2, respectively), along with two enantiomeric pairs of biosynthetic related neolignanes, hancinone C (3) and piperhancin C (4), were isolated from the stems of Piper hancei. Compound 1 is an unprecedented 1',2:1,2'-dicyclo-8,3'-neolignane. Their structures and absolute configurations were elucidated by spectroscopic analyses, X-ray diffraction, and electronic circular dichroism calculations. Among all of the isolates, compounds (+)-1, (-)-1, (+)-2, (-)-2, and (+)-3 could significantly inhibit the production of nitric oxide secreted by lipopolysaccharide (LPS)-induced neuroinflammation in BV-2 microglial cells, with IC50 values of 1.1-26.3 μM. In addition, compound (-)-1 could decrease the mRNA levels of iNOS, IL-6, and TNF-α induced by LPS in BV-2 microglial cells.

Nitrate (NO3-) is known to be actively involved in the processes of mineralization and heavy metal transformation; however, it is unclear whether and how it affects the bioavailability of antimony (Sb) in paddy soils and subsequent Sb accumulation in rice. Here, the effects of NO3- on Sb transformation in soil-rice system were investigated with pot experiments over the entire growth period. Results demonstrated that NO3- reduced Sb accumulation in brown rice by 15.6% compared to that in the control. After amendment with NO3-, the Sb content in rice plants increased initially and then gradually decreased (in roots by 46.1%). During the first 15 days, the soil pH increased, the oxidation of Sb(III) and sulfides was promoted, but the reduction of iron oxide minerals was inhibited, resulting in the release of adsorbed and organic-bound Sb from soil. The microbial arsenite-oxidizing marker gene aoxB played an important role in Sb(III) oxidation. From days 15 to 45, after NO3- was partially consumed, the soil pH decreased, and the reductive dissolution of Fe(III)-bearing minerals was enhanced; consequently, iron oxide-bound Sb was transformed into adsorbed and dissolved Sb species. After day 45, NO3- was completely reduced, Sb(V) was evidently reduced to Sb(III), and green rust was generated gradually. Thus, the available Sb decreased due to its enhanced affinity for iron oxides. Moreover, NO3- inhibited the reductive dissolution of iron minerals, which ultimately caused low Sb availability. Therefore, NO3- can chemically and biologically reduce the Sb availability in paddy soils and alleviate Sb accumulation in rice. This study provides a potential strategy for decreasing Sb accumulation in rice in the Sb-contaminated sites.

Background: Inhibition of cancer cell growth and low in vivo toxicity are two important criteria for the development of anti-cancer drugs. Curcumin is a promising candidate for developing novel anti-cancer drug analogs. The research group designed the 3,5-bis-(3,4,5- trimethoxybenzylidene)-1-methyl-piperidin-4-one analog of curcumin that significantly inhibited the growth of esophageal cancer cells in vivo. In this study, 81 curcumin analogs were synthesized, analyzed both in vitro and in vivo, and their structure activity relationships (SARs) were determined. Methods: Based on the parent structure of curcumin, 81 analogs of 3,5-bis(substitutedbenzylidene)- piperidin-4-one compounds were designed and synthesized. Their anti-cancer activity in the human cancer cell lines was evaluated using the MTT assay, and in vivo toxicity was evaluated in mice. The SARs of selected compounds were analyzed. Results and Discussion: Among the designed curcumin analogs, 61 compounds exerted anti-cancer effects higher than the parent compound in vitro; 23 compounds inhibited cell growth in the human cancer cell line at low concentrations (IC50 values below 1 μM). The acute toxicity of curcumin analogs was tested in mice; 13 compounds were selected, which did not show any obvious toxicity at doses as high as 25.0 mg/kg. The SARs of these shortlisted curcumin analogs were determined. Conclusion: Twenty-three curcumin analogs exhibiting promising in vitro anti-cancer activity and low in vivo toxicity were designed. SAR analysis indicated the optimal functional groups in the molecule required for anti-cancer activity. This study not only suggested a useful strategy to design curcumin analogs for the development of anti-cancer drugs, but also revealed a group of curcumin analogs which could be further explored.

Erosion control materials with long-term effective, economical and environmentally friendly properties play a critical role in controlling erodible and unstable sandy slopes deformed under rainfall. In this study, a novel cellulose-based curing agent was developed and applied as a sustainable sand fixation materisal. The novel cellulose-based curing agent was a dual-polymer composite material (DPCM), which was prepared by mixing two kinds of organic polymer materials: carboxymethyl cellulose (CMC) and polyacrylamide (PAM). The microstructure and composition of DPCM were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The adsorption kinetics of the curing agent on sand particles was discussed by fitting with pseudo-first-order and pseudo-second-order kinetic models. Water resistance and the compressive strength of the sand-fixing specimen at different curing ages were studied. Finally, the DPCM stabilization layer’s resistance to water erosion was investigated using a rainfall simulation test. The results demonstrated that the adsorption kinetic behavior of DPCM adsorbed on sand particles followed pseudo-second-order kinetics. Additionally, the interaction between the DPCM and sand particles was primarily hydrogen bonding, covalent bonds, and physical adsorption. The compressive stress was in the range from 53 to 915 kPa. Sandy slopes treated by DPCM showed excellent resistance to water erosion under a rainfall intensity of 120 mm/h.

For electrically conductive adhesives (ECAs), high electrical conductivity generally conflicts with excellent mechanical properties because electrical conductivity increases while desirable mechanical properties decrease with the increase in loading of conductive fillers or removal of lubricants on the silver filler surface. In this work, a method was developed to improve both the electrical conductivity and mechanical properties of the ECAs by introducing double bonds. Itaconic acid (IA) was used to replace the lubricant on the silver flake (Ag-F) surface, and acrylic acid (AA) was used as part of the ECA resin matrix. IA can replace the lubricant on the Ag-F surface, similar to other short-chain dibasic acids, to improve the ECA electrical conductivity. Furthermore, IA can be polymerized with AA to form covalent bonds between the silver flakes and the resin matrix, enhancing the mechanical properties of ECA. Compared with ECA filled with commercial silver flakes, the electrical conductivity of ECA filled with IA-treated silver flakes increased by ~ 21%, and the lap shear strength increased by ~ 29%.

Twenty new chebulic acid and brevifolincarboxylic acid derivatives, including eight optically pure or achiral compounds (1–7 and 14) and six pairs of enantiomers (8a/8b–13a/13b), along with nine kn...

The chemisorption and catalysis of lithium polysulfides (LiPSs) are effective strategies to suppress the shuttle effect in lithium-sulfur (Li-S) batteries. Herein, multisize CoS 2 particles intercalated/coated-montmorillonite (MMT) as an efficient sulfur host is synthesized. As expected, the obtained S/CoS 2 @MMT cathode achieves an absorption-catalysis synergistic effect through the polar MMT aluminosilicate sheets and the well-dispersed nano-micron CoS 2 particles. Furthermore, efficient interlamellar ion pathways and interconnected conductive network are constructed within the composite host due to the intercalation/coating of CoS 2 in/on MMT. Therefore, the S/CoS 2 @MMT cathode achieves an outstanding rate performance up to 5 C (~548 mAh·g -1 ) and a high cycling stability with low capacity decay of 0.063 and 0.067% per cycle for 500 cycles at 1 and 2 C, respectively. With a higher sulfur loading of 4.0 mg·cm -2 , the cathode still delivers satisfactory rate and cycling performance. It shows that the CoS 2 @MMT host has great application prospects in Li-S batteries.

Catalytic oxidation of formaldehyde (HCHO) at ambient temperature is an effective method for indoor HCHO removal. In this study, Ni/Co-Layered double hydroxides (LDHs) with different molar ratios were successfully synthesized via a one-step hydrothermal method. Their structure and morphology were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET)-specific surface area, X-ray photoelectron spectroscopy (XPS), and H2 temperature-programmed reduction (H2-TPR), respectively. The catalytic activity results show that Ni/Co-LDHs with the Ni/Co ratio of 1:2 exhibited enhanced activity for HCHO decomposition. The removal efficiency of indoor HCHO was up to 99.7% at ambient temperature, and it remained highly stable without any obvious deactivation even after a reaction time of 800 min. The abundant hydroxyl groups were favorable for catalytic activity, which could not only enrich the adsorption of HCHO on the surface of catalysts, but also directly react with HCHO to obtain CO2 and H2O. Moreover, the redox cycles of Ni3+/Ni2+ and Co3+/Co2+ would provide more reactive oxygen species and therefore promote catalytic reaction. This work can provide a new insight into LDH-based catalysts for low-concentration HCHO removal in practical application.

A novel method to prepare crosslinked acrylate self-matting coatings is introduced in this study. Pentaerythritol tetraacrylate (PET4A) was used as a cross-linker to synthesize a series of self-matting crosslinked acrylate coatings (PETs). The gloss value of the PET films was found to decrease as the amount of the cross-linker increased at the three typical incident angles of 20°, 60°, and 85°. Furthermore, the factors that affect glossiness including phase separation, cross linking density, the film-forming temperature, and the film-forming thickness were investigated. PET films provided a transparency of 84% with only 5 wt% of PET4A addition and exhibited a gloss of 5.0 (60°), which illustrates the advantage of using PETs in low-gloss aqueous coatings. In addition, the results of thermogravimetric analysis showed that the PET films exhibit excellent thermal stability. Furthermore, the PET emulsions exhibited a narrow particle size distribution, with a zeta potential of approximately −30.0 mV, revealing their excellent storage stability.

Six new quassinoids, named kumulactone F (1), kumulactone G (2), kumulactone H (4), kumulactone I (5), kumulactone J (6), and kumulactone K (7), a pair of undescribed epimers α- and β-nigakihemiacetal G (3), 15 known quassinoids (8-22), and a mixture of the known compounds α- and β-neoquassin (23) were separated from the dried stems of the medical plants Picrasma quassioides. The chemical structures of all of the new compounds were established by spectroscopic data analyses (HR-ESI-MS, 1D and 2D NMR spectroscopy, and electronic circular dichroism (ECD)). Biologically, compounds 9 and 21 showed toxicity toward the Asian citrus psyllid Diaphorina citri Kuwayama with potent activity even equal to that of the positive control (Abamectin), compound 11 exhibited an excellent neuroprotective effect against SH-SY5Y cells which were pretreated by H2O2 with potent activity equal to that of the positive control (Trolox), and none of them showed cytotoxic activity toward the HeLa or A549 cell lines (IC50 > 100 μM).

Thiol-ene click reactions are more oxygen tolerant alternative to the conventional (meth)acrylate chemistry that is frequently used for the rapid production of photopolymerized networks with numerous desirable properties. To attain a high curing efficiency while maintaining the advantages of thiol-ene systems, a castor oil-based hyperbranched urethane acrylate was employed in this work as a primary oligomer for UV-curable coating formulation. Subsequently, a tetrathiol monomer (PETMP) was introduced into the coating formulation to obtain a thiol-ene system. The effects of PETMP loadings on the UV-curing kinetics and final polymer properties were systematically investigated. Consequently, thiol-ene based films with excellent flexibility and water resistance were obtained as a result of the high efficient thiol-ene photopolymerization. The double bond conversion of the thiol-ene system was found to increase with the addition of more PETMP. Impressively, with the incorporation of 5 wt% PETMP, the resultant UV-cured film had the best acid resistance and exhibited a double bond conversion of 93.6%, a pencil hardness of 6H, a water absorption of 0.76%. Additionally, all of the prepared films were completely transparent and possessed good microstructures. These thiol-ene based films may provide insight into the preparation of high-performance UV-curable coatings with excellent flexibility.

Lignin was used herein to prepare chemical grouting materials as replacements for petroleum-based epoxy precursors. Demethylation, phenolation, and hydroxymethylation were conducted and the products were characterized via FT-IR, 1H NMR, and GPC. A quantitative NMR method was used to study the precise changes in the functional group composition. Raw lignin (RL), demethylated lignin (DML), phenolated lignin (PHL), and hydroxymethylated lignin (HML) were respectively reacted with epichlorohydrin to synthesize various lignin epoxy resin (LEP), including raw lignin epoxy resin (RLEP), demethylated lignin epoxy resin (DMLEP), phenolated lignin epoxy resin (PHLEP), and hydroxymethylated lignin epoxy resin (HMLEP). With LEP as feedstocks, new grouting materials were prepared and the effects of the RLEP content and the LEP variants were investigated. The results demonstrated that the prepared lignin epoxy grouting resin had outstanding viscosity and mechanical properties with RLEP content up to 16%, and this performance greatly exceeded the industry standard. DMLEP, PHLEP, and HMLEP were able to provide better tensile properties, heat-resistance, chemical-resistance and curing performance compared with that achieved with RLEP. Overall, lignin has displayed great potential in replacing petroleum-based materials for the preparation of high-performance chemical grouting materials.

Fluoride removal from aqueous solution by adsorption using fly ash cenospheres (FAC) modified with paper mill lime mud (LM) as composite adsorbent had been investigated. The characterization of FAC and composite adsorbent were analyzed by Scanning electron spectroscope (SEM), Energy dispersive spectrometer (EDS), Brunauer emmett teller (BET) and Fourier transform infrared (FTIR), which demonstrated that the porous structure of composite adsorbent was obtained after surface modification. Adsorption of fluoride on modified fly ash cenospheres was fitted with pseudo-second-order model and Langmuir model. Response surface methodology (RSM) was employed to investigate the effects of F− concentration, pH, adsorbent dosage and temperature on the removal efficiency. Analysis of variance (ANOVA) was used to test the adequacy of the mathematical models. The Nonelectrostatic model of modified fly ash cenospheres adsorbing fluoride was built through the Generalized composite method, indicating that two inner-spherical complexes, ≡SF and ≡SOHF−, were formed in the adsorption process by means of the ligand exchange and surface complexation. Optimization of the adsorption conditions enabled the realization of the practical needs for fluoride contaminated water.

Selective oxidation of sulfides into sulfoxides or sulfones is an important transformation in organic synthesis. Activated carbon supported Nb-based catalysts were prepared by the impregnation method and then characterized by the XRD, TEM and XPS. The characterization results indicate Nb species is amorphous Nb2O5. The catalysts were applied for the catalytic oxidation of sulfides in aqueous phase with H2O2 as the oxidant. Sulfides could be converted into the corresponding sulfoxides or sulfones with high conversion and selectivity at room temperature. The recycling experiments showed the Nb2O5/AC catalysts exhibited good reusability. They could be recycled for 10 times without obvious loss of activity and selectivity.

Cross-linked sustained-release polycarboxylate superplasticizers (SPs) are superior alternative to the comb-type polycarboxylate SPs due to they offer both a high fluidity and a good retention effect for concrete slurry. In this context, a series of cross-linked polycarboxylate superplasticizers were synthesized using acrylic acid, methylallyl polyoxyethylene ether and four different cross-linkers containing ester groups, respectively. The key difference among these four cross-linkers is their molecular weights because they each possessed the different ethoxy content. The fluidity and fluidity retention tests, adsorption performance and scanning electron microscope tests showed that the cross-linked superplasticizers offered good dispersing effects and excellent slump performance. Excitingly, the maximum flow reached up to 394 mm at a water-cement ratio of 0.35 and this high fluidity could be simultaneously maintained for 2 h, which facilitated concrete transport over long distances, therefore improving the practical workability of concrete. Furthermore, it was found that the superplasticizers derived from cross-linkers with higher ethoxy group contents provided cement paste samples with improved fluidity. Evaluation of the hydration heat and setting time demonstrated that the cross-linked polycarboxylate superplasticizers could delay the hydration of cement and the final setting time had been extended by 4 h in comparation with blank samples. After 3, 7 and 28 d, the compressive strength of the cement mortar was improved with increases of molecular weight of the cross-linker in the cross-linked superplasticizers due to the elevation of ethoxy content.

A new chlorinated diphenyl ether, ethyl dichloroasterrate (1), and a new sesquilignan, mappilignan A (2), along with two known diphenyl ethers (3 and 4) and one known sesquilignan (5), were isolated from the stems of Mappianthus tomentosus. The structures of 1−5 were assigned by spectroscopic data analysis and by comparison with literature data. The absolute configuration of 2 was established using experimental and calculated ECD data. Compound 2 displayed inhibition of nitric oxide production in lipopolysaccharide (LPS)-induced BV-2 microglial cells, with IC50 value of 38.87 ± 2.27 μM.

A novel hydrolysable cationic monomer of quaternary ammonium dialkyl maleate was synthesized and subsequently copolymerized with acrylic acid and isobutenyl polyethylene glycol to successfully yield an amphoteric polycarboxylate superplasticizer (APC). The effects of the APC on cement particles were systematically investigated. The fluidity, fluidity retention and mechanical properties were measured to evaluate the performances of the APC and compared with those of a polycarboxylate superplasticizer (PCE). In addition, X-ray diffraction, thermogravimetric and scanning electron microscopy characterization were performed to investigate the influences of the APC on cement particles from microscopic level. Furthermore, the interactions of the APC with cement particles were also investigated via adsorption, hydration heat and zeta potential measurements. It was found that the introduction of a hydrolysable cationic monomer could improve the micro-structure and delay the hydration of cement. Moreover, the APC could increase the cement paste fluidity and fluidity retention.

Fluorescein has been found as an efficient visible-light-induced oxidase mimic and its catalytic performance is group-dependent. Herein, a facile colorimetric strategy for β-galactosidase (β-gal) was developed using fluorescein di β-D-galactopyranoside (FDG) as a probe based on the analyte induced change in oxidase mimicking activity of fluorescein derivatives. FDG doesn’t possess any visible-light-induced oxidase activity and can generate fluorescein and fluorescein mono β-D-galactopyranoside (FMG) in the presence of β-gal. The in situ generated fluorescein and FMG possess high oxidase-like activities under visible-light illumination and could catalyze the oxidation of 3, 3′, 5, 5′-tetramethylbenzidine (TMB) upon short irradiation by light-emitting diode (LED) lamp. Thus, the β-gal activity can be selectively detected in linear range from 0.10 to 12.9 μg mL−1 with a limit of detection (LOD) of 0.04 μg mL−1. We further integrated with the visual detection of α-fetoprotein antigen (AFP) based on the corresponding colorimetric signal induced by β-gal-linked colorimetric immunoassay, a LOD of 0.08 ng mL−1 could be achieved. Significantly, our proposed assay provides a facile sensing platform based on the change in enzyme mimicking activity induced by analytes. In addition, this optical method works without complex synthesis procedure and efficiently avoids participation of unstable H2O2 as an oxidant. Therefore, the present work not only shows the excellent assay performance in β-gal and tumor biomarker detection, but also opens up a new avenue for its application in practical optical sensing.

Functional microorganisms play a vital role in removing environmental pollutants because of their diverse metabolic capability. Herein, a function-oriented fluorescence resonance energy transfer (FRET)-based graphene quantum dots (GQDs-M) probe was developed for the specific identification and accurate sorting of azo-degrading functional bacteria in the original location of environmental samples for large-scale culturing. First, nitrogen-doped GQDs (GQDs-N) were synthesized using a bottom-up strategy. Then, a GQDs-M probe was synthesized based on bonding FRET-based GQDs-N to an azo dye, methyl red, and the quenched fluorescence was recovered upon cleavage of the azo bond. Bioimaging confirmed the specific recognition capability of GQDs-M upon incubation with the target bacteria or environmental samples. It is suggested that the estimation of environmental functional microbial populations based on bioimaging will be a new method for rapid preliminary assessment of environmental pollution levels. In combination with a visual single-cell sorter, the target bacteria in the environmental samples could be intuitively screened at the single-cell level in 17 bacterial strains, including the positive control Shewanella decolorationis S12, and were isolated from environmental samples. All of these showed an azo degradation function, indicating the high accuracy of the single-cell sorting strategy using the GQDs-M. Furthermore, among the bacteria isolated, two strains of Bacillus pacificus and Bacillus wiedmannii showed double and triple degradation efficiency for methyl red compared to the positive control (strain S12). This strategy will have good application prospects for finding new species or high-activity species of specific functional bacteria.

To retrospectively assess the value of the combination of conventional ultrasound and shear-wave elastography (SWE) in evaluating the segmental heterogeneity of liver fibrosis in biliary atresia (BA) patients after Kasai portoenterostomy. A total of 35 BA patients with liver segmental deformation were enrolled. The segmental deformation was assessed by conventional ultrasound followed with SWE examinations for evaluating the liver stiffness. Liver biopsy was performed in 11 patients in the region of SWE measurement and liver fibrosis was assessed using the Metavir classification. Aminotransferase to platelet ratio index (APRI) was calculated for comparison. The correlations between serum biochemical tests with SWE values were evaluated. Spearman’s rank coefficient test was performed to evaluate the correlation between variables. The SWE values of the biopsy segments had significant positive correlations with liver fibrosis severity (r = 0.828, p = 0.001), which was better than APRI (r = 0.366, p = 0.242). The levels of bilirubin and transaminase showed significant correlations with the SWE values at hypertrophic segments in all patients (r from 0.336 to 0.576, all p

Two new steroidal glycosides oxystauntoside A (1) and oxystauntoside B (2), together with sixteen known compounds (3–18) were isolated from the 95% ethanol extract of Merrillanthus hainanensis. Their structures were characterized by extensive spectroscopic analysis including NMR and mass spectra and single crystal X-ray crystallography. The absolute configuration of 1 and 2 were further determined by ECD calculations. All of these compounds were isolated from M. hainanensis for the first time. All the fractions and compounds were tested for the anti-inflammatory activity against the TNF-α factor. The ethyl acetate fraction showed the most potent inhibition (71.3%) at 10 μg/mL and compounds 5 (78.9%) and 9 (73.4%) in this fraction with both carboxyl and phenolic hydroxyl groups showed significant inhibition at 10 μM. Our study provided the first scientific report for the medicinal value of M. hainanensis.

Four new diterpenoids (1–4), three new triterpenoids (12–14), and seven known diterpenoids (5–11) were obtained from an aqueous EtOH extract of the aerial parts of Triadica rotundifolia. The structures of new compounds were determined by spectroscopic techniques. Their absolute configurations were verified via single-crystal X-ray diffraction data, Mo2(OAc)4 induced electronic circular dichroism (ECD), and ECD calculations. The antineuroinflammatory effects of the isolates were assessed by inhibiting NO production in LPS-induced BV-2 microglial cells. Compared with the positive control minocycline (IC50 = 16.1 μM), compounds 3, 8, 11 showed moderate inhibitory activities with IC50 values of 35.9, 17.0, 31.5 μM, respectively.

This work aims to explore the feasibility of self-matting coatings based on soybean oil. A novel reactive waterborne polyurethane (RWPU) dispersion containing unsaturated CC double bonds was synthesized from epoxidized soybean oil (ESO). Subsequently, the RWPU dispersion was copolymerized with hard/soft monomers at different weight ratios to prepare polyurethane/acrylate (MPU) hybrid emulsions. The results reveal the gloss levels of MPUs to be as low as 3.3 gloss units at 60°. A scanning electron microscope and three-dimensional surface profilometer were employed to observe the morphology of the MPU-based films, and the relation between the surface roughness and gloss was determined. Further, thermal gravimetric analysis was conducted to determine the thermal stability of the MPU-based films, and the results denoted that these MPU-based films exhibited excellent thermal stability. Tensile tests indicated that the RWPU dispersion, which was copolymerized at a hard monomer weight of 30%, exhibited a good tensile strength of 13.2 MPa and a high elongation percentage of 578%. Furthermore, after one year, the MPU emulsions exhibited a narrow particle size distribution and their zeta potential values were approximately −30.0 mV, revealing the excellent storage stabilities (>one year) of all the MPU emulsions.

Six new lignans with various type of linkage between two C6-C3 fragments (1a, 1b, 2a, 2b, 3, 4), two new meroterpenoids (5, 6) and 24 known compounds (7–30) were isolated from an EtOH extract of the stems and leaves of Piper puberulum. The absolute configurations of enantiomers 1a and 1b were determined by single-crystal X-ray diffraction analysis, 2a and 2b were determined by comparing their calculated and experimental ECD spectra. Biogenetically, all the new lignans may come from the polymerization of two molecules of hydroxychavicol (30). In the anti-neuroinflammation activity assay, the IC50 values of fifteen compounds were lower than those of the positive control minocycline, and compound 1a showed good activity, but its enantiomer 1b showed no activity. Compound 1a have notable anti-neuroinflammatory activity, and can significantly decrease mRNA levels of proinflammatory cytokines (IL-1β, IL-6, TNF-α) in a dose-dependent manner.

Two new cadinane sesquiterpene glucosides (1, 2), two new phenylpropanoid glycosides (3, 4), and two new diterpenoid glucosides (5, 6), as well as 6 known compounds were isolated from the stems of Tinospora sinensis. The structures of these compounds were elucidated by extensive spectroscopic analysis and chemical methods. The absolute configuration of compound 1 was determined by timedependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations and in situ dimolybdenum CD method. All the isolated compounds except for compounds 7, 11 and 12 were evaluated for their anti-neuroinflammatory effect by inhibiting the nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine BV-2 microglial cells, and compound 4 showed anti-neuroinflammatory activity with IC50 values 42.90 μM in vitro assay.

Synthesis, characterization, and coating performance of castor oil (CO)-based waterborne hyperbranched polyurethane acrylate (WHPUA) emulsions are highlighted in this work. Herein, a second-generation CO-based hyperbranched polyester (C20) was synthesized by introducing the renewable CO as a B3 core and dimethylolpropionic acid as an AB2 monomer via a pseudo-one-pot condensation procedure. Three types of CO-based WHPUA emulsions were prepared through the addition of the hyperbranched C20 with maleic anhydride (MA) and the isocyanate-bearing semiadduct (IPDI-HEA) at different MA/IPDI-IH molar ratios without the addition of any emulsifiers. The prepared emulsions were further formulated into UV-curable coating formulations and exposed to a medium-pressure mercury lamp. Consequently, the obtained UV-cured coatings exhibited outstanding adhesion performance, excellent transparency, and an acceptable degree of final double bond conversion. Owing to a relatively low concentration of hydrophilic units and a large number of acrylate functionalities in the waterborne oligomer, the obtained films were endowed with high crosslinking density and low hydrophilic nature, thus producing enhanced tensile strength, pencil hardness, water resistance, and chemical resistance. Due to their combination of renewable materials, a waterborne system and a UV-curing technique, these CO-based WHPUA emulsions offer promising opportunities to be used as environmentally friendly coatings.

Photoresponsive complex emulsions are prepared in a three-phase system consisting of two oils: hexane (H) and perfluorooctane (F). An aqueous solution of a mixed surfactant of fluorosurfactant, F(CF2)x(CH2CH2O)yH (Zonyl FS-300), and a synthesized light-responsive surfactant, 2-(4-(4-butylphenyl)diazenylphenoxy)ethyltrimethylammonium bromide (C4AZOC2TAB) was employed as the continuous phase. Complex emulsions with various geometries were prepared by one-step vortex mixing and a temperature-induced phase-separation method. It was noticed that the topology of the complex emulsion was highly dependent on the mass ratio of Zonyl FS-300/C4AZOC2TAB. Light microscopy images showed that phase inversion from an H/F/W- to an F/H/W-type double emulsion via a Janus emulsion was achieved by gradually increasing the mass ratio of C4AZOC2TAB/Zonyl FS-300. Upon UV/blue light irradiation, the topology of complex emulsions was turned to switch from an F/H/W double emulsion to a Janus emulsion to an entirely inverted H/F/W d...

Block copolymers (BCPs) have stimulated widespread research interest due to their applications as facile templates in the fabrication of optimized thermosets with micro– or nanostructured morphologies. In the present work, a novel block copolymer was obtained from a commercial poly(styrene-block-butadiene-block-styrene) (SBS) triblock copolymer precursor by a two-step process including reaction with hydrogen peroxide in a water/dichloroethane biphasic system to achieve an epoxidized derivative with a 46 mol% degree of epoxidation (thus denoted as eSBS46), which was then followed by reaction with 1-(2-aminoethyl)piperazine (AEP, thus yielding eSBS46-AEP) as a reactive functional group that was incorporated to prepare nanostructured epoxy thermosetting blends. As a result of the oxirane ring-opening achieved (to a conversion degree of 10 mol%) by reaction with AEP, the nanostructured morphology was converted from spherical micelles in the case of eSBS46 to branched wormlike micelles for eSBS46-AEP. ...

A novel waterborne polyurethane (WPU) resin with low gloss and micro-roughness was synthesized by the prepolymer and self-emulsification method. It was achieved by introducing multi-hydroxyl castor oil and reactive bisphenol A-type epoxy E-44 or E-51 resin to polyurethane prepolymer to form a cross-linking network structural waterborne polyurethane emulsion, which demonstrated the distinctive characteristic of the shear-thinning pseudoplastic fluid with a yield stress. The chemical structures and rough surface morphologies of the WPU films were characterized by FTIR-ATR, LCRS, AFM, SPMS and SEM, respectively. The specular gloss values at 20°, 60° and 85° incident angles were measured, and the values of different kinds of roughness parameters were obtained. The relationship between the gloss and the castor oil content was also discussed in detail. In general, this WPU resin endowed the film with micro-roughness, moderate hardness and good adhesive strength, making it very prospective in substitution for the traditional low gloss coatings.

A novel environmentally friendly method was developed to fabricate hollow core–shell conductive nanoparticles using a natural and nontoxic material, nanocrystalline cellulose (NCC), as the template. The NCC used in this study has nano-scale rod-like structure. After the oxidization to dialdehyde cellulose, the insulated NCC was functionalized by poly(dopamine) (PDA) in weakly alkaline conditions through Schiff base reaction and self-polymerization. The Schiff base can be hydrolyzed in an aqueous acetone solution via ultraviolet radiation so that the hollow structure constructed. This structure not only strengthened the mechanical properties but also provided more active sites for silver deposition. Utilizing the chelating ability of the catechol groups in PDA, electroless plating method was used to form the silver coating layer. Scanning electron microscope and Dynamic Light Scattering measurements indicated that these nanoparticles (NPs) had well-defined morphology and a mean diameter of 100–120 nm. Moreover, these prepared Ag–DA–NCC0 NPs exhibited excellent conductivity. Their electrical resistivity reached 0.2 mΩ·cm, which is much higher than that of many other conductive particles used in conductive adhesive.

Six previously undescribed oleanane-type triterpenoid saponins, fortunosides A–F, together with six known ones, were isolated from the aerial parts of Lysimachia fortunei Maxim. Their structures were established by spectroscopic data analyses (1D, 2D-NMR and HRESIMS) and chemical methods. All isolated triterpenoid saponins were evaluated for their cytotoxicity against four human liver cancer cell lines (SMMC-7721, Hep3B, HuH7, and SK-Hep-1). Three saponins with the aglycone protoprimulagenin A exhibited moderate cytotoxicity against all of the tested human cancer cell lines, with IC50 values ranging from 4.76 to 15.12 μM.

A series of low gloss waterborne polyurethane acrylate (WPUA) hybrid emulsions with different weight ratios of hard/soft monomers of acrylic monomers were synthesized successfully. Compared with the traditional low gloss coatings that achieve low gloss effects by adding a large number of pigments, fillers or both to roughen the surfaces, the low gloss effect of these WPUA emulsions was achieved through the formation of self-roughed surfaces during film formation with zero loading of extraneous dulling agent. Gloss levels could be as low as 3 units at 60° incident angle. The chemical structures of these WPUA films were characterized by nuclear magnetic resonance carbon spectroscopy ( 13 C NMR), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The rough surface topographies of these WPUA films were observed by scanning electron microscopy (SEM). The particle size distributions of these WPUA emulsions were analyzed by DLS measurement. The polymeric phase separation behaviors of these WPUA films were assessed by DSC analysis. In general, the WPUA emulsions that afforded films with good hardness, good adhesion strengths and excellent thermal stabilities, showed a great advantage in applications of low gloss aqueous coating.

Graphene is an important class of carbon-based materials that exhibits excellent thermal conductivity along its layers. In order to construct a 3D thermal transport material, herein, SiO2@C was successfully inserted into the reduced graphene oxide (rGO) layers to enhance its axial thermal transport performance via vacuum-assisted electrostatic self-assembly and pyrolysis processes. The formed rGO-SiO2@C composite exhibits an enhanced axial thermal conductivity of 6.65 W/(m*K) and an in-plane thermal conductivity of 36.54 W/(m*K). Moreover, it also displays good electromagnetic shielding properties, with the high total shielding effectiveness (SET) value of 45.59 dB, and an ultralow shielding effectiveness reflection (SER) value of 2.72 dB. Our work provides a simple method to construct a hybrid as a 3D conductive and thermal conductive network.

We herein reported a series of superplasticizers that were synthesized from the macro-monomer polyethylene glycol methacrylate and the monomers acrylic acid, sodium allyl sulfonate, or vinylphosphonic acid at different molar ratios. In order to explore the influence of COO-, SO32-, and PO32- on the performance of superplasticizers, fluidity tests and plastic viscosity tests were carried out to evaluate the dispersion performance of these polymers. Furthermore, the conformation of these superplasticizers in calcium hydroxide solution was analyzed via dynamic light scattering and Ca2+ concentration tests. The results showed that these superplasticizers exhibited the best dispersion effect when the molar ratio of COO-:SO32- and COO-:PO32- was 3:1. In addition, the calcium complexing capacity of the phosphonate groups was higher than that of the sulfonate ions, leading to the lower plastic viscosity of cement pastes containing the superplasticizer with COO-:PO32- at a ratio of 3:1. This study provides valuable information for the application in practical engineering.

Sixteen chebulic acid derivatives, including nine new (1–9) and seven known (10–16) ones, were isolated from an ethanol extract of the branches and leaves of Balakata baccata. The structures of the new compounds were elucidated by their UV, IR, HRESIMS, NMR, electronic circular dichroism (ECD) and single-crystal X-ray diffraction data. The effects of all the isolates on antineuroinflammatory and antioxidant activities were evaluated. Compared with the positive control minocycline (IC50 = 1.21 ± 0.71 μM), compounds 1–16 with IC50 values being greater than 50 μM, displayed almost no effects on the inhibition of NO production in LPS-induced BV-2 microglial cells, however, the results of antioxidant activity for compounds 1–16 showed significant DPPH-radical scavenging abilities with EC50 value ranging from 3.98 to 14.24 μM, while the EC50 value of positive control vitamin C was 14.31 μM. At last, the results of PCR (qRT-PCR) analysis showed that compound 1 could enhance the expression of antioxidases (HO-1, GCLC, and NQO1) at the mRNA levels.

Magnesium phosphate cement-fly ash (MPC-FA) has been synthesized as a new cutoff wall material to control lead pollution in groundwater. A series of experiments were conducted to investigate its properties including adsorption, mechanical performances, morphologies, microstructure and migration of Pb(Ⅱ) through the magnesium phosphate cement-fly ash cutoff walls. X-ray microcomputed tomography was used to get the microscale three-dimensional real geometry images of the cutoff walls. The internal structural parameters were analyzed through digital image processing technology. Lattice Boltzmann method (LBM) was employed to simulate the hydraulic conductivity and three-dimensional velocity fields distribution of cutoff walls. The optimized fly ash ratio (in mass) of cutoff walls was 40%, and the sodium dihydrogen phosphate/monopotassium phosphate molar ratio was 1:1. The compressive strength and flexural strength during 14 days were 23.2 MPa a nd 5.6 MPa, respectively. The laboratorial hydraulic conductivity of MPC-FA was 1.22 × 10−9 m/s and the theoretical maximum adsorption capacity was 467.87 mg/g. The pore-network model showed that the connected porosity of MPC-FA was 14.45%, and the most of the pores and throats in cutoff walls were microflow paths (radius ≤ 12 μm). The hydraulic conductivity simulated by LBM basically coincided with the measured results, and the velocity fields indicated that the flow paths were tortuous and complex. Under different breakthrough concentration standards, the penetration of Pb(Ⅱ) at initial concentration of 4000 mg/L through cutoff walls with thickness of 0.6 m, 1 m, 1.2 m, 1.5 m needed 8–10, 22–28, 31–41 and 49–64 years, respectively. The model obtained by Visual MODFLOW numerical simulation showed that the contaminant plume of Pb(Ⅱ) was controlled after 7400 days in the polluted site with MPC-FA cutoff walls, which supported that the MPC-FA met the requirements for good control of Pb(Ⅱ) in the lead-contaminated sites.

This paper reports on a novel self-matte or bulk-matte waterborne polyurethane coating composite with inherently extremely low gloss. The coating composite was comprised of a siloxane-containing waterborne polyurethane (SPU) resin and a crosslinked waterborne polyurethane (CPU) resin. The CPU resin was mainly responsible for fabricating the micro-rough surface of the film, which was achieved by a crosslinking reaction between the waterborne polyurethane and bisphenol A-type epoxy E-44 resin. The SPU resin was used to improve the comprehensive properties of the film, which was ascribed to the addition of silane coupling agent KH792. Compared with traditional matte coatings, this coating composite made it possible to avoid high loadings of matting agent and to arrive at highly flexible low-gloss finishes. Gloss levels of as low as a few tenths of a percent, even at high incidence angles, have been achieved with zero loading of extraneous dulling agent. The chemical structures of the SPU and CPU resins were characterized by FTIR-ATR and NMR spectra. The micro-rough topographies and surface rough degrees of the SPU, CPU and their 50%/50% composite films were measured by SEM and MSP, respectively. The particle sizes and particle morphologies of the SPU and CPU resins were imaged by TEM. Finally, the comprehensive properties of the SPU, CPU and their 50%/50% composite resins were evaluated, including the water contact angle, film transparency, tensile strength and storage stability.

We prepared poly(N-isopropylacrylamide-co-4-tert-butylcalix[8]arene) (PNIPAM-TBCX) hydrogels by copolymerization of N-isopropylacrylamide (NIPAM) with 4-tert-butylcalix[8]arene (TBCX) to capture hazardous pentachlorophenol (PCP) from aqueous solution. Adsorption experiments showed that the adsorption capacities of PNIPAM-TBCX hydrogels reached 1.96, 2.08 and 2.02 mg PCP per 1 g of hydrogel, while the molar percentage ratio of TBCX in the hydrogels was as low as 0.5%, 0.7% and 1%. The equilibrium adsorption of PCP on the hydrogels was studied using different adsorption models. In addition, the PNIPAM-TBCX hydrogel still retained its performance when regenerated several times by immersing in water at 323 K.

Manganese dithionate (MnS2O6), formed in the leaching process of pyrolusite slurry with SO2, is a concern because of its ability to decrease the purity of MnSO4 (industrial raw material). Information regarding the oxidation and recovery of dithionate ion is scarce. In this study, we investigated the leaching process of MnO2 with MnS2O6 in the liquid phase. The leaching reaction presented one way to oxidize MnS2O6. The most suitable operating parameters on the oxidation efficiencies of MnS2O6 were established as follows: MnO2 dosage, 21.7 g L−1; agitation speed, 450 rpm; initial H2SO4 concentration, 1.81 mol L−1; initial MnS2O6 concentration, 28.5 g L−1; and reaction temperature, 372.5 K. Under the optimum conditions, the removal efficiency of 97.55% for MnS2O6 was obtained in 30 min. The experimental results showed that increasing the initial concentrations of MnS2O6 and H2SO4 and the reaction temperature resulted in a decrease in the content of MnS2O6. The dithionate oxidation process could be well modeled by the shrinking core model with an inert product layer, which indicated that the process was controlled by the interfacial chemical reaction. The reaction orders with respect to initial H2SO4 concentration and initial MnS2O6 concentration were 1.64 and 0.18, and the activation energy was 60.1 kJ mol−1 as well as pre-exponential factor was 5.9 × 106.

For various applications, it is essential to enhance the colloidal stabilization of carbon nanotube (CNT) dispersions. Here, the polymers with carbazole pendants of poly(4-(N-carbazolyl)methylstyrene-bl-poly(ethylene glycol) methyl ether methacrylate) (PCMS5-b-PAPEG73 and PCMS16-b-PAPEG43) and PCMS30, synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization, were used for noncovalent functionalization of multiwalled carbon nanotubes (MWCNTs) in tetrahydrofuran (THF), offering efficient colloidal stabilization. Meanwhile, the adsorption of polymers onto MWCNTs was investigated. The results showed that the MWCNTs decorated with these three polymers in THF exhibited different colloidal stabilization and adsorption capacity. Moreover, the MWCNT dispersions could be stabilized for days and their colloidal stabilization elevated with the increase of polymer concentrations. The block copolymer PCMS16-b-PAPEG43 exhibited the optimal adsorption and dispersion capability for MWCNTs. The...

In this study, novel macro porous Ni2+-imprinted chitosan foam adsorbents (F-IIP) were prepared using sodium bicarbonate and glycerine to obtain a porogen for adsorbing nickel ions from aqueous solutions. The use of the ion-imprinting technique for adsorbents preparation improved the nickel ion selectivity and adsorption capacity. We characterised the imprinted porous foam adsorbents in terms of the effects of the initial pH value, initial metal ion concentration, and contact time on the adsorption of nickel ions. The adsorption process was described best by Langmuir monolayer adsorption models, and the maximum adsorption capacity calculated from the Langmuir equation was 69.93mgg-1. The kinetic data could be fitted to a pseudo-second-order equation. Our analysis of selective adsorption demonstrated the excellent preference of the F-IIP foams for nickel ions compared with other coexisting metal ions. Furthermore, tests over five cycle runs suggested that the F-IIP foam adsorbents had good durability and efficiency.

The high flexibility and adaptability of the soft actuator have attracted wide attention. However, under the stimulation of the external environment, the complex and controllable movement of materials remain a challenge. In this work, we make a bilayer composite film simply and quickly by depositing silicone rubber (Ecoflex00-30) on the side of the plant parchment. It spontaneously controls deformation and responds sensitively in the water. This bilayer composite film exhibits a good stable actuation effect and reversibility in a humid environment or in water. We cut the strips of plant parchment into different fiber directions and control the lateral gradient in the thickness direction to achieve complex and controllable motion (bending, S-shaped, -shaped and spiral). Inspired by the plant tendrils, we design and built a soft gripper that can achieve 30 times its own weight in the water, demonstrating promising bioinspired applications.

From the perspective of waste utilization, the invasive species, Eupatorium adenophorum was used to prepare biochar, which was then loaded with iron/nickel bimetals. Compared with pure biochar, the biochar-loaded nano-iron/nickel bimetals have a significant effect on the removal of 2,4,6-trichlorophenol (2,4,6-TCP) from water, and their degradation rate can be increased by 39.7%-71.6% under different conditions. Several factors can influence the removal of 2,4,6-TCP, including the load ratio, pH of the solution, concentration of 2,4,6-TCP, and coexisting ions in water (HCO3−, SO42−, NO3−). Based on the density functional model (DET), Ni can activate H2 (produced in the reaction between nano-Fe and H2O) to convert to H*, which can then substitute Cl. The activation energy is 109.5 kJ/mol, indicating the reaction is easy to take place.

Understanding the structure–property relationship of polyurethane (PU) binders is of critical importance in the construction engineering applications. A series of rapid room temperature-curable PU binders were prepared using polyoxypropylene glycol as the soft segments, along with polymethylene polyphenylene isocyanate and 4,4′-methylene-bis(2-chlorobenzenamine) as the hard segments. This work investigated the influence of the hard segment content (40 wt%, 45 wt%, and 50 wt%) and the soft segment molecular weight (1000 g/mol, 2000 g/mol, 3000 g/mol, and 4000 g/mol) on the microphase structure of the PU binders. Their influence on the compressive behaviors, flexural behaviors, impact strengths, and slant shear strengths of the PU-based polymer concretes was also investigated. Structural characterization revealed that increasing either the hard segment content or the larger soft segment molecular weight effectively enhanced hydrogen bonding as well as microphase separation. Our results also demonstrated that a higher hard segment content resulted in better mechanical performance and shorter pot life. In addition, the PU-based polymer concrete using 2000 g/mol polyoxypropylene glycol reached optimal mechanical performance when the hard segment was held constant. Hence, varying the hard segment content and soft segment length can be an effective method to adjust the engineering performance of PU-based polymer concrete.

To study the chemical composition of the extract of cedar pine needle methylene chloride. Methods: The paper used silica gel and Sephadex LH-20 column chromatography to separate and purify, and carried out structural identification based on physical and chemical properties and spectral data. At the same time, gallic acid was preliminarily separated by high-performance liquid chromatography (HPLC), the separation conditions of gallic acid were determined, and the content change of gallic acid after tannin was acid-decomposed was determined, proving that the extract may contain decomposable hydrolysis Tannin or compound tannin. Results: Five compounds were isolated from the dichloromethane extract of cedar pine needles, which were identified as: ferulic acid (1), osthol (2), β-phenylacrylic acid (3), paeonol (4), Magnolol (5). Conclusion: All compounds except Compound 5 were isolated from this plant for the first time.