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The present study focuses on the terpolymer of styrene (St), isoprene (Ip), and butadiene (Bd) synthesized together in cyclohexane at 70°C with neodymium (Nd) compound, alkylaluminum, and chlorinating agent (Cl) rare earth cocatalyst system. The resultants possessed atactic St-St sequences and high cis-1,4 polyconjugated olefins in macromolecular chains besides controllable composition. The composition of the St-Ip-Bd terpolymers and molecular weight ([M.sub.w]), molecular weight distribution ([M.sub.w]/[M.sub.n]) were controlled through the adjustment of Nd compound, alkylalumium, monomers feed ratio (St/Ip/Bd), and [Nd]/[monomers]. With the inventory rating of St raised from 15% to 55%, the content of St in the terpolymers got increased from 2% to 15%. And the content of the Ip segments and Bd segments in the terpolymers increased from 33% to 56% and from 28% to 54%, respectively, with the proportion of Ip/Bd varied from 1/2 to 2/1. As the [Nd]/[monomers] varied from 1.0 x [10.sup.-3] to 5.0 x [10.sup.-4], the molecular weight increased from 1.3 x [10.sup.4] to 2.7 x [10.sup.4]. According to the proton nuclear magnetic resonance (1H-NMR) and 13C-NMR, it was proved that both microstructures of polybutadiene segments and polyisoprene segments were high cis-1,4-configuration. A single glass-transition temperature was observed in the differential scanning calorimetry curve., INTRODUCTION Taking a world view of the current research in the field of synthetic rubber industry, one may easily find out that poly(conjugated-olefin) rubbers played an essential role in the [...]

Metal sulfide semiconductor photocatalysts have been widely used in photocatalytic hydrogen evolution reactions due to their good light absorption properties and high photostability. However, the metal sulfide photogenerated carriers of these catalysts are susceptible to recombination, which reduces the rate of hydrogen production. In this study, ZnIn2S4 was doped with the transition metal ion Ni2+ to regulate and control the absorption sidebands of ZnIn2S4, improve the catalyst's responsiveness to visible light, and hence increase the hydrogen production rate. Ni–ZnIn2S4 catalysts with varying doping ratios were prepared, and the optimal doping ratio of 1.0% was selected for further experiments. A WO3/Ni–ZnIn2S4 composite photocatalyst was synthesized using the hydrothermal method to produce a heterojunction with a constant doping ratio of 1.0%. Loading WO3 on this catalyst enhanced the light absorption intensity, improved the photogenerated carrier separation efficiency, and significantly increased the hydrogen evolution rate of the catalyst by 2.1 times. Finally, an g-C3N4 QDs/WO3/Ni–ZnIn2S4 catalyst was prepared by loading quantum dots for sensitization. The g-C3N4 quantum dots served as a sensitizing role, greatly improved the light absorption intensity, and further improved the hydrogen evolution rate of the catalyst, which was increased to 9.29 mmol/(g·h). [ABSTRACT FROM AUTHOR]

Amino‐containing functionalized syndiotactic polystyrenes with high melting temperatures and temperature stability are synthesized by the direct polymerization of amino‐containing styrenic monomers in the presence of a half‐sandwich scandium catalyst system [(C5Me4SiMe3)Sc(CH2C6H4NMe2‐o)2]/[Ph3C][B(C6F5)4]. The high syndiotactic poly(N,N‐dimethylamino)styrene (rrrr > 99%), then used as novel polymer supports, effectively anchored Pd nanoparticles (3 wt % of Pd) with a diameter of 4 or 5 nm that were uniformly dispersed on polymer matrix. [ABSTRACT FROM AUTHOR]

Establishing cultivated grassland in the Qinghai-Tibet Plateau region is an effective method to address the conflict between vegetation and livestock. However, the high altitude, low temperature, and arid climate in the region result in slow regeneration and susceptibility to degradation of mixed cultivation grassland containing perennial legumes and gramineous plants. Therefore, we aim to through field experiments, explore the feasibility of establishing mixed cultivation grassland of Poaceae species in the region by utilizing two grass species, Poa pratensis L. and Puccinellia tenuiflora . By employing a mixture of P. pratensis and P. tenuiflora to establish cultivated grassland, we observed significant changes in forage yield over time. Specifically, during the 3rd to 6th years of cultivation, the yield in the mixed grassland was higher than in monocultures. It exceeded the yield of monoculture P. tenuiflora by 19.38% to 29.14% and surpassed the monoculture of P. pratensis by 17.18% to 62.98%. Through the analysis of soil physicochemical properties and soil microbial communities in the cultivated grassland, the study suggests that the mixed grassland with Poaceae species can enhance soil enzyme activity and improve soil microbial communities. Consequently, this leads to increased soil nutrient levels, enhanced nitrogen fixation efficiency, and improved organic phosphorus conversion efficiency. Therefore, establishing mixed grasslands with Poaceae species in the Qinghai-Tibet Plateau region is deemed feasible., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Xiang, Shi, Liu, Liang, Zhang and Li.)