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A γ′ phase strengthened NiCoCrFeAlTiMoW alloy was prepared in a vacuum arc melting furnace, and X-ray diffractometer (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and tensile testing machine were used to investigate the coarsening behavior and the evolution law and mechanism of mechanical properties of the γ′ phase after 200 h long-term aging at 750, 850 ℃ and 950 ℃.The results show that γ′ phase remains spherical during the aging process when the aging time is extended, γ′ phase size gradually increases and the solidification phenomenon occurs at 750, 850 ℃ and 950 ℃. The alloy has a high diffusion activation energy with a value of 357 kJ/mol.This is mainly due to the fact that the matrix is a high entropy solid solution with complex composition, and the diffusion of Al and Ti atoms in the matrix becomes difficult due to the hysteresis diffusion effect. The yield strength of the alloy gradually increases after aging at 750 ℃, the yield strength after aging at 850 ℃ first increases and then decreases, and gradually decreases after aging at 950 ℃. The change in the yield strength of the alloy is caused by the increase in the size of the γ′ phase, which leads to a shift in the precipitation strengthening mechanism of the alloy.

The single‐unit monomer insertion (SUMI), derived from living/controlled polymerization, can be directly functionalized at the end or within the chain of polymers prepared by living/controlled polymerization, offering potential applications in the preparation of polymers with complex architectures. Many scenarios demand the simultaneous incorporation of monomers suitable for different polymerization methods into complex polymers. Therefore, it becomes imperative to utilize SUMI technologies with diverse mechanisms, especially those that are compatible with each other. Here, we reported the orthogonal SUMI technique, seamlessly combining radical and cationic SUMI approaches. Through the careful optimization of monomer and chain transfer agent pairs and adjustments to reaction conditions, we can efficiently execute both radical and cationic SUMI processes in one pot without mutual interference. The utilization of orthogonal SUMI pairs facilitates the integration of radical and cationic reversible addition‐fragmentation chain transfer (RAFT) polymerization in various configurations. This flexibility enables the synthesis of diblock, triblock, and star polymers that incorporate both cationically and radically polymerizable monomers. Moreover, we have successfully implemented a mixing mechanism of free radicals and cations in RAFT step‐growth polymerization, resulting in the creation of a side‐chain sequence‐controlled polymer brushes. [ABSTRACT FROM AUTHOR]

The linkage between air pollution and individual subjective well-being (SWB) has attracted increasing attention. This study conducted an individual-specific questionnaire survey in Beijing and used ordered logistic regression to analyze the association between air pollution and individual subjective well-being. It was found that with the aggravation of air pollution, the happiness index of residents decreased significantly. The overall difference of residents' happiness index increased and then decreased with the increase of air pollution. The largest difference of residents' happiness index was found in the range of AQI>150-200 for all respondents. Age and motivation to wear anti-haze masks were the significant factors affecting this difference. The mean value of resident happiness in the group of age <20 years old was significantly higher than the groups of age≥30 years old (F=10.652, P< 0.05). The happiness index of residents in the group with the highest motivation to wear masks was significantly lower than the other motivation groups. Both age and motivation to wear anti-haze masks may reflect residents' concern about the health effects of air pollution, which may be an important reason for their reduced subjective well-being. Therefore, in order to mitigate the effects of air pollution on residents' well-being, future strategies should provide relevant health protection policies in response to residents' health concerns in addition to reducing the emissions of air pollutants. [ABSTRACT FROM AUTHOR]

Hydrophobically modified ethoxylated urethane (HEUR) with different structures was synthesized and confirmed by gel permeation chromatography, Fourier transform infrared spectroscopy and nuclear magnetic resonance (1H NMR). We propose the relationship between the temperature insensitivity model and the thickening mechanism of HEUR/latex/Fe2O3/Zn3(PO4)2/BaSO4 suspensions. Meanwhile, the temperature insensitivity of HEUR/C suspensions is the result of two main associations: intermolecular interactions bridging the hydrophobic tails of HEURs and the hydrophobic groups tightly adsorbing onto the latex particle surfaces. A smaller ratio of viscosity (Rv) at 1 s−1 from the steady state condition indicates the better temperature insensitivity of viscosity. The higher degree of crystallinity and rheological activation energy corresponds to a great extent with better temperature insensitivity due to stronger association. The temperature insensitivity is consistent with the longer hydrophobic chain, which was proven by hysteresis tests and oscillatory shear measurements. The storage stability was enhanced in the lockstep with a hydrophobic length of HEUR, which is consistent with the rougher surfaces of HEUR/C films. As an appealing method, the results are meaningful and instructive for coating storage and application. An intermolecular network model of HEUR/C is presented, which suggests intermolecular associations in the bridging of hydrophobic tails and the hydrophobic groups adsorbing onto the latex particle surfaces. A temperature insensitivity mechanism model combined with rheology results and AFM is also proposed to clarify the relationship between temperature insensitivity and storage stability and the hydrophobic tail length. [ABSTRACT FROM AUTHOR]