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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]

• 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]

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]

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]

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]