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Environmental protection talents training (EPTT) is recognized as a key prerequisite for maintaining environmental sustainability, and in order to study the influence of each player on EPTT. This paper innovatively constructs a tripartite evolutionary game model of government, university and enterprise. The equilibrium points and evolutionary stabilization strategies of each participant are solved by replicating the dynamic equations, and the behaviors of each subject in EPTT are analyzed so as to clarify the behavioral characteristics and optimal strategies of the government's participation in EPTT. The results show that enterprises occupy a more important position in influencing government decisions. The government should reduce the financial incentives for enterprises and replace them with greater policy support. Meanwhile, the government should actively promote the cultivation mechanism that integrates universities and enterprises. The results of the study can provide a decision-making basis for the government to promote the sustainable development of EPTT. [ABSTRACT FROM AUTHOR]

The fluorescence blinking and low multiphoton emission of quantum dots (QDs) have limited their application in lasing, light-emitting diodes, and so on. Coupling of single QDs to plasmonic nanostructures is an effective approach to control the photon properties. Here plasmon–exciton systems including Au nanoparticles and CdZnSe/ZnS QDs were investigated at the single particle level. With the modulation of the local electromagnetic field, the fluorescence intensity of single QDs is increased, accompanied by a significant suppression in blinking behavior, and the lifetime is shortened from 15 ns to 2 ns. Moreover, the second-order photon intensity correlation at zero lag time g2(0) of coupled single QDs is larger than 0.5, indicating an increased probability of multiphoton emission. The enhancement factors of radiative and nonradiative decay rates of QDs coupled with Au nanoparticles are calculated. The sharply increased radiative decay rate can be comparable to the nonradiative Auger rate, leading to dominated multiple exciton radiative recombination with PL intensity enhancement, suppressed blinking, lifetime shortening, and multiphoton emission. The results of the exciton decay dynamics and emission properties of single QDs in this work are helpful in exploring the mechanism of plasmon–exciton interaction and optoelectronic application of single QDs. [ABSTRACT FROM AUTHOR]

Polydiacetylene (PDA) has been actively employed as sensing vehicles owing to its unique colorimetric feature upon environmental stimulation. Here, blue phase PDA has been constructed by topological polymerization of commercial diacetylene acid (DA) noncovalently modified by guest amines. Specifically, PDA including 1‐naphthylmethylamine noncovalently bonded on both sides exhibits long‐term stability in polar organic solvents. The stability of PDA depended upon both the structures of the DA and the guest molecule, underscoring a stabilizing mechanism dominated by noncovalent bonding and strong π–π interaction. Accordingly, the blue phase PDA shows a colorimetric response from blue to red upon exposure to stimuli influencing noncovalent bonding and π–π interaction, such as elevated temperature, the existence of acid or alkali at concentrations as low as 50 ppm. Therefore, the PDA developed in this study has the potential of serving as a colorimetric sensor for detecting subtle environment changes and especially for measuring the quality of polar organic solvents recovered from industrial effluent. [ABSTRACT FROM AUTHOR]

The superoleophobic, superhydrophilic, and flame-retardant coatings were obtained through layer-by-layer (LBL) technology using fly ash (FA) as the core. Chitosan (CS), phytic acid (PA), and fluorosurfactant (FS50) were assembled onto FA by LBL assembly using the principle of electrostatic adsorption. The CS and PA were recycled assembled on FA core for 10 layers, which was further deposited with FS50 molecules as the final layer (marked as FA@CS-PA10@FS50). Multifunctional coatings consisted of the FA@CS-PA10@FS50 powders and polymer binders were formed and could be used on a variety of substrates of various shape and size. The obtained coatings presented superoleophobicity, superhydrophilicity, and flame retardance. The contact angles (CAs) of coated substrates were all greater than 150° towards various oils (rapeseed oil, diesel, hexadecane, and dodecane), while achieved water CAs as low as 0°. The as-fabricated coatings could efficiently separate different oil/water mixtures and lotions while avoiding pollution of the separated materials. The coatings also achieved superior flame retardance, and the fire was self-extinguished within 13 s. Moreover, it also obtained excellent mechanical durability. [ABSTRACT FROM AUTHOR]

A series of chiral ligands were synthesized using chloramphenicol base as starting materials. These ligands were applied to the asymmetric catalytic reactions of terminal alkynes with aldehydes to obtain a propargyl alcohol product in high yield (80–94%) with excellent enantioselectivities (82–96%). [ABSTRACT FROM AUTHOR]

Dynamic properties are vital for the working reliability of aft stern tube bearings. However, the determination of such properties currently involves several simplifications and assumptions. To obtain its dynamic characteristics accurately, the aft stern tube bearing was divided into several bearing segments. The oil film reaction force was considered in the calculation of shaft alignment, and the journal deflection and actual oil film thickness were obtained accordingly. Subsequently, the perturbed Reynolds equation was solved using the finite difference method when the dynamic characteristics of journal bearings with finite width were evaluated. Then, a calculation program was developed and verified by comparing with the results of other studies. Finally, the dynamic characteristics were calculated under different revolutions. The results showed that the stiffness at the vertical direction of the aft stern tube bearing was several times that of the horizontal direction and varied with the revolutions of the shafting system. These findings can provide the foundation for the precise calculation of the journal trajectory under dynamic conditions, as well as for the evaluation of the oil film thickness. Moreover, the results led to favorable conditions for the accurate calculation of the shafting whirling vibration.