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Environmental information disclosure (EID) is an important embodiment of corporate social responsibility. With the awakening of public awareness of environmental protection and the increasing pressure of environmental preservation, enterprises tend to strategically manipulate environmental information for the pursuit of profit, which will consequently lead to environmental information disclosure falsification (EIDF) and disruption of both the market regulatory order and the development of green economy. In this article, support vector machine (SVM) technique is applied to construct the detection model of corporate EIDF. Based on the theory of "public pressure," the detection indicators will be improved from three aspects: public pressure, corporate governance, and financial indicators. The training set and test set are constructed by combining the manually collected cases of environmental administrative penalties from 2015 to 2019 with the indicator information of nonfinancial listed enterprises in China's A-share market, and the SVM detection performance is compared with the logistic regression of the benchmark model. To solve the problem of category imbalance, we have introduced the Borderline-SMOTE oversampling technique. Based on the detection results of SVM and Borderline-SMOTE, we find that the Borderline-SMOTE-SVM model has the best detection performance, surpassing the SVM and logistic regression models. These conclusions have constructive policy implications for regulatory agencies, investors, the third-party service sector, enterprises, and government policy-making to achieve high-quality corporate EID. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) and CO2, two chemical wastes that urgently need to be transformed in the environment, are converted simultaneously in a one‐pot catalytic process through the synergistic coupling of three reactions: CO2 hydrogenation, PET methanolysis and dimethyl terephthalate (DMT) hydrogenation. More interestingly, the chemical equilibria of both reactions were shifted forward due to a revealed dual‐promotion effect, leading to significantly enhanced PET depolymerization. The overall methanol yield from CO2 hydrogenation exceeded the original thermodynamic equilibrium limit since the methanol was in situ consumed in the PET methanolysis. The degradation of PET by a stoichiometric ratio of methanol was significantly enhanced because the primary product, DMT was hydrogenated to dimethyl cyclohexanedicarboxylate (DMCD) or p‐xylene (PX). This synergistic catalytic process provides an effective way to simultaneously recycle two wastes, polyesters and CO2, for producing high‐value chemicals. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) and CO2, two chemical wastes that urgently need to be transformed in the environment, are converted simultaneously in a one‐pot catalytic process through the synergistic coupling of three reactions: CO2 hydrogenation, PET methanolysis and dimethyl terephthalate (DMT) hydrogenation. More interestingly, the chemical equilibria of both reactions were shifted forward due to a revealed dual‐promotion effect, leading to significantly enhanced PET depolymerization. The overall methanol yield from CO2 hydrogenation exceeded the original thermodynamic equilibrium limit since the methanol was in situ consumed in the PET methanolysis. The degradation of PET by a stoichiometric ratio of methanol was significantly enhanced because the primary product, DMT was hydrogenated to dimethyl cyclohexanedicarboxylate (DMCD) or p‐xylene (PX). This synergistic catalytic process provides an effective way to simultaneously recycle two wastes, polyesters and CO2, for producing high‐value chemicals. [ABSTRACT FROM AUTHOR]

Cisplatin (CDDP) is a potent first-line antitumor drug but suffers severe side effects and poor pharmacokinetics. Its complexation with polycarboxylic acids, such as polyglutamic acids, is generally used to fabricate nanoformulations for CDDP delivery; however, the multiple strong complexations makes intracellular drug release slow. Herein, we report a novel polyphenol-metal coordination method to fabricate CDDP-incorporated core-shell nanoparticles, which are stable in blood circulation but dissociate in the tumor. Methoxyl-PEG terminated with one or two gallic acids (PEG-GA or PEG-GA2) complexed CDDP and produced well-defined nanoparticles (PEG-GAx/Pt) with CDDP loading contents as high as 17.7% to 29.8%. The PEG-GAx/Pt nanoparticles were very stable in the physiological conditions and had slow blood clearance and efficient tumor accumulation, but dissociated quickly and released CDDP in response to the tumor acidity or elevated levels of reactive oxygen species (ROS). PEG-GAx/Pt nanoparticles exhibited improved antitumor efficiency against 4 T1 breast cancer and A549 lung carcinoma with much-reduced toxicity compared to free CDDP. The work demonstrates a new strategy of cisplatin-polyphenol coordination for developing platinum drugs' nanomedicines. Unlabelled Image [ABSTRACT FROM AUTHOR]

• Palladium nanoparticles favour over-hydrogenation in butyne hydrogenation. • In contrast, palladium sulfide catalyst is highly selectivity for butyne hydrogenation. • Pd 4 S offers greater than 90% alkene selectivity for both but-1-yne & but-2-yne as reactants. • DFT calculations show desorption of alkene is more favourable than hydrogenation. The partial hydrogenation of but-1-yne and but-2-yne was studied with a view to probing the difference between external and internal alkynes. Catalysts with Pd and Pd 4 S active phases were prepared on a carbon nanofiber support. Over the simple Pd catalyst over-hydrogenation was common which restricted alkene selectivity greatly – 25–35% depending on temperature. In contrast, the Pd 4 S active phase offered exceptional alkene selectivity (maximum of 92–93% alkene selectivity for both the external and internal alkyne). DFT calculations were subsequently used to rationalise this difference in product selectivity – sulfur appears to change the geometry of the active site in Pd 4 S and create a surface which favours alkene desorption relative to over-hydrogenation. This work further emphases the potential of palladium sulfide phases as an alternative to purely metallic palladium catalysts for partial alkyne hydrogenation. [ABSTRACT FROM AUTHOR]

Fluorinated block copolymers, hexafluorobutyl methacrylate-block-poly(glycidyl methacrylate) (HFBMA- b -PGMAs, FPGs) were synthesized by atom transfer radical polymerization (ATRP) and applied to fabricating hydrophobic cotton fabrics. Since the HFBMA block provided low surface free energy and the PGMA blocks served as anchors with cotton fibers, the FPGs modified cotton fabrics showed excellent water repellency. The results indicated that nano- and microscale rough structures were created with combining HFBMA blocks onto surfaces of micro-sized cotton fibers. Since the HFBMA blocks were chemically bound to the cotton fibers by epoxy groups of PGMA blocks, the modified cotton fabrics possessed long-term high stability and durability. Furthermore, the important cotton fabric parameters such as tensile strength, color, and haptics were all unaffected by the FPGs modification, which revealed potential for applications. [ABSTRACT FROM AUTHOR]

Zwitterionic (ZI) polymers have great potential for dispersion and adsorption effects because of their dual functional groups (acidic and basic) grafted on polymer matrices. The ZI monomer 3-(2-(methacryloyloxy) ethyl) dimethylammonio-propane-1-sulfonate (DMAPS) and novel amphiphilic polycarboxylate copolymers (APCs) were prepared and characterised. The dispersion and adsorption behaviours of APCs as superplasticisers in a cement system in the absence and presence of clay were investigated. The results indicated that APCs had excellent dispersing ability, and a notable feature was that APCs could effectively inhibit the preferential adsorption of APCs into clay. A mechanistic study including dispersion, adsorption, zeta potential and x-ray diffraction revealed that, compared with traditional polycarboxylate superplasticisers, APCs with ZI groups were more easily adsorbed on the surface of clay but were not incorporated into the layer structure of the clay. This work not only fabricated a new superplasticiser with potential for development, but also provided a concept for preparing new superplasticisers to solve problems involved in their application. [ABSTRACT FROM AUTHOR]

A series of UV-curable oligomers based on bisphenol-F epoxy resin were synthesized via end-capping of acrylic acid (AA) and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) in different ratios. Along with the increase of AMPS content, viscosities of modified resins reduced obviously. Integrated performance of cured films was also evaluated. Water swelling and contact angle tests indicated that the hydrophilicity was enhanced by the incorporation of sulfonate and amide groups into the coatings. Thermal degradation behaviors showed that the char residue, as well the glass transition temperature of the cured films was increased with the rising AMPS proportion, though the initial decomposition temperature declined. Moreover, doping of plentiful AMPS caused a remarkable enhancement in elongation at break, which was ascribed to greater flexibility of polymer chains and reduced density of crosslinking structure. Cured films with AMPS modified showed strong adhesive strength resulted from strong hydrogen bonding formed between amide sulfonate groups from AMPS and polar surface of glass substrates. For pure AA modified film, it was unaffected in NaOH solution (2 wt%) for 24 h. While for AMPS modified film, the film could be completely removed in several minutes when exposed to alkali solution. The modified epoxy films with these attractive features had prospective applications in temporary protective coatings, which could resist acid and organic solvents while would be easily wiped off from the substrate by soaking in the alkali solution. [ABSTRACT FROM AUTHOR]

Star polymers (CD-POEGMAs and CD-PNIPAMs), and pseudo-graft polymer (PADMA-(CD-POEGMAs) x ) formed from PADMA with adamantyl(Ad) pendants and CD-POEGMAs by host–guest inclusion complexation were prepared and characterized. This work compared the thermoresponsive and self-assembly mechanisms of the POEGMAs as branches to that of PNIPAMs branched cyclodextrin cored star polymers. In contrast to CD-PNIPAMs which behaved abrupt and intensive dehydration process near its LCST, CD-POEGMAs exhibited thermally induced aggregation process with consecutive conformation changes during the temperature increase process, and gradually self-assembled into cyclodextrin centered aggregates with hydrophobic methacrylate backbone and dehydrated POEGMAs side chains. Moreover, this work provided a supramolecular method controlling and adjusting the thermoresponsive properties of pseudo-graft PADMA-(CD-POEGMAs) x formed from CD-POEGMAs and PADMA via inclusion complexation, which underwent a reversible thermally induced transition from micelle to nano-aggregates. Pseudo-graft PADMA-(CD-POEGMAs) x behaved gradually conformation changes as temperature rising, and self-assembled into aggregates with hydrophobic methacrylate backbone, residual Ads, and dehydrated POEGMAs side chains. [ABSTRACT FROM AUTHOR]

Based on monovinyl β-CD monomer (GCD), random copolymers (PTCDs) were first synthesized by AA, TPEG, and GCD, and characterized by FTIR and GPC. The application performances of PTCDs as superplasticizers in cement and concrete were investigated considering dispersion, adsorption, setting times, and compressive strength. The results indicated that PTCDs had more excellent applied performance compared with AA-co-GCD copolymers, and the outstanding feature is that PTCDs had a mild tunable retarding effect. When with certain amount of CD pendants and PEO side chains, PTCD2had the best dispersion and mild retarding performances, which were mainly attributed to the joint steric hindrance effect provided by CD pendants and PEO side chains. This study offers a new type of superplasticizer from CD and its derivatives with excellent dispersion and retarding performances to concrete engineering. [ABSTRACT FROM AUTHOR]

Highlights: [•] MA and SMAS were introduced into the TPEG-type PCEs to improve the dispersion and flow retention abilities. [•] This paper discussed the dispersion and adsorption effects of TPEG-type PCEs compared with conventional MPEG-type PCEs. [•] PCE2 has excellent water-reducing and flow-retaining abilities, which is attributed to the synergistic effects of steric hindrance and electrostatic repulsive force. [•] Application results showed that PCE2 can be used as high-range water reducer in practical applications. [Copyright &y& Elsevier]

Highlights: [•] The synthetic processes of β-cyclodextrin (CD) based functional monomers were improved and characterized in detail. [•] Based on the monovinyl CD based monomer, a new copolymer (PCDs) bearing CD pendants was synthesized and used as superplasticizer. [•] PCDs behaved excellent dispersion ability and strong retarding effect. [ABSTRACT FROM AUTHOR]

Highlights: [•] Diethanolamine modified lignin (DML) has been synthesized and firstly used for the production of Portland cement. [•] DML is effective in the improvement of grindability and particle size distribution, and mechanical properties of the produced cements. [•] In contrast to lignin, both the initial and final setting times of tested cements with DML increased obviously. [Copyright &y& Elsevier]

Abstract: Comb-like polycarboxylate copolymers (PCs) were synthesized and first used as the dispersants for kaolin suspensions. The apparent viscosity, adsorption behavior, zeta potential, rheological behavior, and TEM images of concentrated kaolin slurries deflocculated with these copolymers were systematically investigated. Sodium acrylate homopolymer (SA) was selected as a reference in order to contribute to the knowledge of how the electrostatic interaction and molecular structure of these copolymers influenced the dispersion, adsorption, and rheological properties of colloidal kaolin suspensions. The results showed that the dispersion of kaolin slurries mainly depended on the synergistic effects of electrostatic interaction and steric hindrance for APEG type comb-like copolymers. PC2 bearing proper carboxylic groups and side chains produced stable dispersion and fluidity in concentrated kaolin slurries. Based on the electrostatic and steric effect of comb-like copolymers, the kaolin slurries displayed a shear thickening behavior, and the Herschel–Bulkley model well described their rheological behaviors. [Copyright &y& Elsevier]

Mechanically robust shape‐morphing materials that can transform from miniaturization into complex structures are highly desirable for real‐world device applications. However, fabricating mechanically robust yet geometrically complex 3D shape‐morphing structures with excellent functionality and high load‐bearing capacity remains a challenge. Inspired by drum tower buildings, a simple, rapid, and universal method is presented for fabricating multifunctional shape‐memory smart devices with complex and rigid 3D kirigami geometry in the two‐stage epoxy‐amine‐acrylate photopolymer systems. In the first‐stage reaction, transparent polymer films with a Tg of 29–49 °C are obtained by the epoxy‐amine chemistry. The shape‐memory programming process allows the first‐stage film with a drum tower‐inspired 2D kirigami pattern to be manipulated into an unsupported 3D structure. In the second‐stage reaction, UV‐induced free‐radical polymerization of methacrylate groups in the first‐stage network is employed to rapidly lock the programmed 3D kirigami structure with a Tg of 66–138 °C. The drum tower‐inspired 3D kirigami structure withstands 1000 times its own weight. The shape memory fluorescent 3D device and shape memory electronic 3D device are engineered by combining the two‐stage photopolymer system and a 3D kirigami structure. This work represents a versatile method to create multifunctional shape‐memory devices with rigid 3D geometry for potential applications. [ABSTRACT FROM AUTHOR]

A biocompatible Bi@mSiO 2 @MnO 2 nanocomposite is fabricated using a facile stepwise reaction method, which exhibits powerful theranostic performance for CT/MR imaging-guided enhanced PTT/CDT/chemotherapy of tumours. [Display omitted] Cancer is a leading cause of death worldwide and seriously threatens the health of humans. The current clinical treatments for cancer are not efficient and always lead to significant side effects. Herein, a biocompatible and powerful theranostic agent (Bi@mSiO 2 @MnO 2 /DOX) is fabricated using a facile stepwise reaction method. The Bi nanoparticles (NPs) are coated by mesoporous silica to protect the Bi NPs from oxidation, which guarantees the stable photothermal effect of the Bi NPs. When the Bi@mSiO 2 @MnO 2 /DOX nanocomposites (NCs) accumulate in the tumour site, hyperthermia is generated by Bi NPs under near-infrared (NIR) light irradiation for photothermal therapy (PTT), and the generated heat triggers the release of DOX for chemotherapy in the tumour. In addition, the MnO 2 of the NCs responsively catalyses endogenous H 2 O 2 to generate O 2 , raising the oxygen level to enhance the effect of chemotherapy in the tumour microenvironment (TME), and consumes glutathione (GSH) to produce Mn2+ for magnetic resonance (MR) imaging. Under acidic TME conditions, H 2 O 2 and Mn2+ also produce toxic hydroxyl radical (· OH) for chemodynamic therapy (CDT). Furthermore, the Bi NPs can also be used as excellent contrast agents for X-ray computed tomography (CT) imaging of tumours with a high CT value (6.865 HU mM−1). The Bi@mSiO 2 @MnO 2 /DOX NCs exhibit a powerful theranostic performance for CT/MR imaging-guided enhanced PTT/CDT/chemotherapy, which opens a new prospect to rationally design theranostic agents for tumour imaging. [ABSTRACT FROM AUTHOR]

The flexural strength and compressive strength are the two most important parameters that characterize the mechanical properties of cement-based materials, but the two are usually mutually exclusive or negatively correlated. The flexural strength of cement-based materials cannot be effectively improved by a single nanomaterial without reducing their compressive properties. Therefore, compounding various micro–nano materials, fully utilizing their respective advantages, and developing composite materials with new properties and application characteristics are important techniques for enhancing the mechanical properties of cement-based materials. This study aimed to investigate the synergistic enhancement of the mechanical properties of concrete by using microcrystalline cellulose (MCC) and nano-silica (NS) composites. MCC and NS were mixed and modified to synthesize MCCNS materials, which were added to cement slurry for experiments. Results indicated that the flexural strength and compressive strength of the cement paste with MCCNS materials were significantly increased compared with those of the cement pastes without MCCNS or with only NS. The flexural strength of the cement paste with MCCNS-1 was increased by 47%, 20%, 6.3%, and 6.8% after curing for 1, 7, 28, and 56 days, respectively. Meanwhile, compressive strength was also increased by 14.4%, 6.3%, 6.8% and 6.5%, respectively. In addition, the reaction mechanism was speculated through a variety of test results. The addition of MCCNS material facilitated the formation of additional C-S-H, which also contributed to enhancing the mechanical properties of cement paste. • Novel nanocomposites were synthesized using MCC and NS through adsorption-phase reaction and sol–gel methods. • The mechanical properties of cement-based materials were notably enhanced by incorporating MCCNS materials. • The volcanic ash activity of NS led to additional C-S-H formation, improving the mechanical strength of the cement paste. [ABSTRACT FROM AUTHOR]

Pt nanoparticles supported on MgAl-hydrotalcite catalyst was prepared via impregnation-reduction method followed by an in situ rehydration process, which showed excellent catalytic performance towards aerobic oxidation of glycerol to glyceric acid. Glycerol (GLY) aerobic oxidation in an aqueous solution is one of the most prospective pathways in biomass transformation, where the supported catalysts based on noble metals (mainly Au, Pd, Pt) are most commonly employed. Herein, Pt nanoparticles supported on rehydrated Mg x Al 1 -hydrotalcite (denoted as re-Mg x Al 1 -LDH-Pt) were prepared via impregnation-reduction method followed by an in situ rehydration process, which showed high activity and selectivity towards GLY oxidation to produce glyceric acid (GLYA) at room temperature. The metal-support interfacial structure and catalyst basicity were modulated by changing the Mg/Al molar ratio of the hydrotalcite precursor, and the optimal performance was achieved on re-Mg 6 Al 1 -LDH-Pt with a GLY conversion of 87.6% and a GLYA yield of 58.6%, which exceeded the traditional activated carbon and oxide supports. A combinative study on structural characterizations (XANES, CO-FTIR spectra, and benzoic acid titration) proves that a higher Mg/Al molar ratio promotes the formation of positively charged Pt δ+ species at metal-support interface, which accelerates bond cleavage of α-C–H and improves catalytic activity. Moreover, a higher Mg/Al molar ratio provides a stronger basicity of support that contributes to the oxidation of terminal-hydroxyl and thus enhances the selectivity of GLYA. This catalyst with tunable metal-support interaction shows prospective applications toward transformation of biomass-based polyols. [ABSTRACT FROM AUTHOR]

• Novel organic/inorganic nanocomposites LNTS-1 and CNTS-2 were synthesized from NS and alpha thioctic acid. • Compared with bulk CNTS-2, linear LNTS-1 can effectively improve the macro flexural strength of cement-based materials. • The results of adsorption experiments show that LNTS-1 has strong adsorption on calcium ions. Using organic/inorganic nanocomposites to optimize the microstructures of cement hydration products at the micro/nanometre scale is a promising method for improving the mechanical properties of cement-based materials. One type of novel nanohybrid material modified by the flexible autonomous healing polymer poly-TA (thioctic acid) was synthesized and used as a highly efficient mechanical improvement agent for cement paste. The nanohybrids linear LNTS-1 and bulk CNTS-2 were synthesized from silane-coupled nanosilica and alpha thioctic acid. Due to the existence of hydrogen bonds, coordination bonds and dynamic covalent S S bonds, this type of linear poly-TA with a certain amount of calcium content exhibited good self-healing properties. Linear LNTS-1 can effectively improve the macro flexural strength of cement-based materials without a negative effect on their compressive strength. The flexural strength of cement pastes with 1.0‰ LNTS-1 increased by 11.9%, 15.6%, and 16.9% after curing for 3, 7, and 28 d compared with the control cement paste. The results of adsorption experiments show that nanohybrid LNTS-1 has strong adsorption on calcium ions, which affects the formation of cement hydration products. [ABSTRACT FROM AUTHOR]

A ternary system thermoresponsive hydrogel, poly( N -isopropylacrylamide- co -hydroxyethyl methylacrylate polycaprolactone)/hydroxypropyl cellulose (or P(NIPAAm- co -HEMAPCL)/HPC), was prepared via “alkynyl/azide” click chemistry between the azide modified graft copolymer P(NIPAAm- co -HEMAPCL-N 3 ) and the alkynyl modified HPC (or alkynyl-HPC). The structures of P(NIPAAm- co -HEMAPCL-N 3 ) and alkynyl-HPC were characterized by 1 H NMR, SEC and FT-IR, and the results demonstrated that the mole ratio of the alkynyl and azide functional groups, and the feed ratios of HPC, PCL, and PNIPAAm could be easily adjusted. The incorporation of PCL and HPC dramatically enhanced the compression modulus of the P(NIPAAm- co -HEMAPCL)/HPC hydrogel, which ranged from 500 to 1000 g/cm 2 . Due to the immiscibility of HPC and PCL, a heterogeneous and semicontinuous structure was observed via SEM. The incorporation of HPC accelerated the water absorption rate and enhanced the hydrogel's ability to shed water. The swelling–deswelling and compressive properties could also be adjusted by changing the feeding ratio. The hydrogel exhibited reversible swelling–deswelling behavior after three “swelling–deswelling” cycles. [ABSTRACT FROM AUTHOR]

The production of higher alcohols by the catalytic conversion of synthesis gas (CO + H2) is one of the most promising approaches for the utilization of nonoil resources, in which bimetallic catalysts based on Cu and Fischer–Tropsch (FT) reaction active elements (e.g. Co, Fe, Ni) are efficient and cost-effective candidates. Herein, we demonstrate the fabrication of core–shell Cu@(CuCo-alloy) nanoparticles (NPs) embedded on a Al2O3 matrix via an in situ growth of CuCoAl-LDH nanoplatelets on aluminum substrates followed by a calcination–reduction process, and they serve as efficient catalysts toward CO hydrogenation to produce higher alcohols. The composition, particle size and shell thickness can be tuned by changing the Cu/Co molar ratio in the LDH precursors, and the best catalytic behavior was obtained over the Cu/Co (1/2) catalyst with a CO conversion of 21.5% and a selectivity (C6+ slate 1-alcohols) of 48.9%, which is superior to the traditional modified FT catalysts. XPS, in situ FTIR spectroscopy and HAADF-STEM revealed that the unique electronic and geometric interaction between Cu and Co in the Cu@(CuCo-alloy) NPs contributes to the significantly enhanced catalytic performances. In addition, the 3D hierarchical structure of the Cu@(CuCo-alloy)/Al2O3 catalyst facilitates mass diffusion/transportation as well as prevents hotspot formation, accounting for its stability and recyclability. The Cu@(CuCo-alloy)/Al2O3 catalyst with significantly improved catalytic behavior can be potentially used in CO hydrogenation to produce higher alcohols. [ABSTRACT FROM AUTHOR]

Poly(amino acid)-type macromolecules (PAAs), poly(ethylene glycol) -b- poly(aspartic acid) (PEG-PAAs), and poly(ethylene glycol)- b -poly(glutamic acid) (PEG-PGAs) were synthesized, and their states in aqueous solutions were studied. PEG-PAAs and PEG-PGAs were first used as novel polycarboxylate superplasticizers, and their dispersion and adsorption behaviors were investigated in cement slurries in the absence and presence of montmorillonite (MMT) clay. The results demonstrated that both PEG-PAAs and PEG-PGAs not only showed excellent water reducing and fluidity retention capabilities but also exhibited remarkable MMT clay tolerance. In contrast to the stretched molecular conformation of traditional polycarboxylate superplasticizers (PCEs), the hydrophobic main chain and the side methylene and ethylene linkers connected to the carboxylic groups of PAA and PGA segments resulted in self-assembly of the PEG-PAAs and PEG-PGAs in aqueous solutions, and the self-assembled nanosized aggregates exhibited relatively uniform spherical morphologies with average sizes of 30–100 nm. Carboxylic groups located on the periphery of the nanoaggregates acted as anchors and adsorbed on the surfaces of the cement particles. The nanoaggregates and the stretched hydrophilic PEG side chains, which jointly produced and enhanced the steric hindrance to prevent cement particle aggregation and hydration, resulted in notable dispersion capabilities. Total organic carbon (TOC), X-ray diffraction (XRD), and thermogravimetry–differential scanning calorimetry (TG-DSC) analyses revealed that the adsorption between the MMT clay and PAA nanoaggregates was surface adsorption (rather than interlayer adsorption), and this significant finding could be ascribed to the enlarged steric hindrance of the PAA nanoaggregates, which prevented the interlamination adsorption consumption of MMT clay to PAAs and revealed the outstanding clay insensitivity. This study provides a new perspective and strategy to design novel poly(amino acid)-type superplasticizers (PAAs) with excellent dispersion performances and improved clay tolerance. [Display omitted] • Poly(amino acid)-type superplasticizers (PAAs) with enhanced dispersing performance for cement doped with clay impurities. • The self-assembled nanoaggregates of PAAs enhanced steric hindrance and resulted in notable dispersion capabilities. • The enlarged steric hindrance of PAAs prevented interlamination adsorption and revealed outstanding clay insensitivity. [ABSTRACT FROM AUTHOR]

Abstract: A novel Eu-complex Eu(TTA)2vinyl-phen has been designed and synthesized via simple reaction as an efficient fluorescent sensor for F−, CH3COO−, and H2PO4 −. The anion-sensitivity of Eu-complex was evaluated using a series of anion in DMSO solution. On binding with F−, CH3COO−, or H2PO4 −, fluorescence quenching of Eu-complex was easily observed, while no obvious fluorescence change could be observed in the presence of other anions. More importantly, the Eu-complex exhibited excellent selectivity and sensitivity for F− and H2PO4 − in water/DMSO (5/5) solution. The titration results of UV–vis, fluorescence, and 1H NMR spectra indicated that the fluorescence quenching can be attributed to the strong hydrogen bonding interaction between anions and imidazole group of Eu-complex. To meet application requirements for biological and environmental detection in water, we successfully prepared a Eu-based fluorescent hydrogel probe using Eu(TTA)2vinyl-phen and N-isopropyl acrylamide (NIPAAm) as monomers through free radical copolymerization in DMF. Emission spectra titration experiments indicated that this hydrogel probe can effectively recognize H2PO4 − (detection limit 10−5 M), but cannot recognize F− and CH3COO− in pure water. To the best of our knowledge, this is first report that Eu-based fluorescent hydrogel probe for H2PO4 − detection in pure water. In addition, the emission of Eu-complex is also found to be sensitive to molecular oxygen through energy back-transfer mechanism. [Copyright &y& Elsevier]