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The curing characteristics and tensile properties of sulfur and mercaptan modified chloroprene rubber(CR) were evaluated using carbon black free formulation were studied .The results showed that the specific surface area of magnesium oxide(MgO) affected the curing rate of CR, with the increase of the specific surface area of MgO, the curing efficiency improved. The specific surface area of MgO also effected the tensile properties of vulcanizated CR. The carbon black free formulation A and formulation B were applicable to evaluate curing characteristics and tensile properties of mercaptan modified CR, and the evaluation results may not be compareable. The carbon black free formulation was suitable for evaluating the curing characteristics and tensile properties of sulfur modified and mercaptan modified CR, and the precision of the test results could meet the requirements of ASTM D 3190—2006.

The contents of soap and organic acid in emulsion polymerized styrene-butadiene rubber determined by indicator titration and potentiometric titration in ISO 7781 were compared. The differences between the determination principles and results of the two methods were compared, and the accuracy of the results was investigated by standard addition experiment. The results showed that the results of potentiometric titration and indicator method were consistent. When testing the soap content in emulsion polymerized styrene-butadiene rubber, the indicator method was greatly affected by amine antioxidant and filling oil. But the potentiometric titration method was less affected by amine antioxidant and was not affected by filling oil, so the determination result was more accurate.

All-inorganic cesium lead halide perovskite materials have potential applications in mini/micro-LED display applications due to their excellent photoelectric properties. However, these materials have an uncontrollable tendency to form large-sized crystals and poor stability, which is not conducive to miniaturized optoelectronic applications. Herein, a novel Cs4PbBr6@KBr color conversion film (Cs4PbBr6@KBr CCFs) with both excellent luminescence properties and high stability was in situ constructed by using inkjet printing technology. The improvement in performance is attributed to the reduction in perovskite defects within the structure and the isolation of oxygen and water by the surface modification layer, which is related to the higher solubility product of KBr. The Cs4PbBr6@KBr CCFs printed on a PET flexible substrate present a high-resolution dot matrix of 16.7 μm and a homogeneous and bright green emission with a high photoluminescence quantum yield of 94%. Moreover, the Cs4PbBr6@KBr CCFs retain 65% of their initial intensity after being aged at 70 °C for 16 h, which is superior to that of perovskite CCFs without the coating of KBr. These results indicate that the Cs4PbBr6@KBr composite has excellent potential in realizing mini/micro-LED displays with high resolution and anti-counterfeiting lables. [ABSTRACT FROM AUTHOR]

Laser‐driven white light exhibits exceptional brightness and directionality, making it particularly well‐suited for spotlight applications. Yet, attaining high‐quality white light remains challenging due to the sluggish heat dispersion and inconsistent light uniformity of color converters. In this study, an innovative phosphor‐in‐glass (PiG) film architecture is introduced, aiming to achieve superior quality laser‐driven light, where the traditional Y3(Ga,Al)5O12:Ce3+ (YAGG:Ce3+) PiG film is topped with a Al2O3‐in‐glass (AiG) film. The heightened thermal conductivity of the AiG film facilitates quicker dissipation of heat, consequently elevating the luminescence saturation threshold from 14 to 16 W mm−2 and luminous flux from 1243.8 to 1475.9 lm. The increased light scattering attributed to the AiG film also effectively disperses both laser and emitted light, significantly enhancing the angular consistency of color rendering index (Ra). This improvement is evident as the coefficient of variation (Cv) decreases dramatically from 16.69% to 0.25%. Moreover, by integrating CaAlSiN3:Eu2+ (CASN:Eu2+) into the PiG film and fine‐tuning the YAGG:Ce3+ and CASN:Eu2+ ratio, a high‐quality laser‐driven white light achieving an impressive color rendering index (Ra) of 88.7 and offering an adjustable correlated color temperature (CCT) has been developed. This innovation holds tremendous potential as a versatile spotlight solution for both indoor and outdoor settings. [ABSTRACT FROM AUTHOR]

As a result of global warming, the thawing settlement disasters of permafrost in the Qinghai–Tibet Engineering Corridor (QTEC) have intensified, which has serious effects on the safe operation of permafrost highway engineering. In this work, a prediction model for the thawing depth of permafrost subgrade in the QTEC under the climate warming scenario was established. Based on the survey results of permafrost ice content along the QTEC and the classification of thawing settlement risks, the zoning characteristics of thawing settlement of permafrost subgrade in the QTEC were obtained and analyzed. The results showed that the thawing depth of permafrost underlying the 26 m width subgrade in the QTEC will mainly remain below 9 m, and the area with a thawing depth of 6~9 m will have the widest spread within the next 20 years. The thawing settlement will be between 0.02 m and 5.45 m, with an average value of about 0.93 m after 20 years. Furthermore, after 50 years, the thawing depth of permafrost underlying the 26 m width subgrade will almost always be greater than 9 m, and the average thawing settlement will be about 1.12 m. Within the next 20 to 50 years, the risk of permafrost subgrade thawing settlement in the QTEC will be the most significant risk type, and this effect will mainly be distributed in the Kunlun Mountains, Chumar River Plain, Kekexili Mountains, Beiluhe Basin, Tanggula Mountains and intermountain Basins. [ABSTRACT FROM AUTHOR]

This study explores how doctoral graduates weigh considerations of employment sectors and cities in their career decision‐making processes. Guided by Social Cognitive Career Theory and a Four‐quadrant Model, researchers analysed interviews from 40 STEM doctoral graduates in China. Findings demonstrate that self‐efficacy, outcome expectations and goal‐setting were factors in participants' interests and selections of academic careers. Three types of doctoral graduates were identified: (1) highfliers, (2) academic loyalists and (3) city pickers. While participants prioritize employment sectors and cities differently, cities played a significant role in their career choices which intersected with gender and class factors. Female doctoral graduates were more inclined to follow their partners, while those from socioeconomically disadvantaged backgrounds tended to prioritize cost of living factors at the expense of pursuing opportunities in top‐tier cities. Implications suggest that factors undergirding doctoral graduates' career choices rely on the interaction between geographical locations and employment sector opportunities. [ABSTRACT FROM AUTHOR]

Whilst China has become home to the second largest doctoral education system in the world, with over 20% of its doctoral graduates taking up postdoctoral researcher positions inside and outside of China, a lack of information regarding the expectations of these doctoral graduates in pursuing postdocs has resulted in a failure to meet their expectations, leading to insufficient institutional support for their career development. In order to improve this situation and provide more tailored institutional support for Chinese postdocs, we conducted interviews with 30 doctoral graduates from elite Chinese universities from February 2020 to December 2021 to understand their expectations for and experiences of postdocs. The data identified four expected‐to‐accumulated capitals during postdoc experiences: personal scientific capital, discipline‐related social capital, institution‐related social capital and family‐related social capital. Among these, the primary consideration for engaging in postdocs is to enhance personal scientific capital in both qualitative and quantitative aspects. Chinese doctoral graduates who choose domestic postdocs have higher expectations for increasing institution‐based social capital, while those who go abroad expect to develop discipline‐related social capital within the international academic community. Understanding these expectations will be instrumental in developing optimal approaches to providing institutional support for the career development of Chinese postdocs. [ABSTRACT FROM AUTHOR]