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Poly(lactic acid) (PLA)‐based nanocomposite incorporated with zeolite MCM‐22 precursor at extra‐low loading of 0.2–0.8 wt% is directly prepared by melt compounding and injection moulding method. The Vicat softening temperature raises up to >155 °C, much higher than that of pure PLA (63 °C), which is very beneficial for its application in many fields such as a container for hot food due to its environmentally friendly property. The high heat resistance property is believed to not be caused by the improvement of crystallinity and glass transition temperature but resulting from the obstruction of PLA polymer chain movement originating from >CO···HOSi hydrogen bonding between PLA molecules and the in situ exfoliated MWW zeolite nanosheets with abundant exposed surface silanol groups. Such a method would pave a new way not only for designing more types of thermal stable polymer composites but also for delaminating multi‐layered zeolite precursors. [ABSTRACT FROM AUTHOR]

Paper is the most important writing carrier and its degradation (acidification, aging, and ink removal) is a major issue in the protection of cultural heritage. In this work, we first propose alkali ion-exchanged Y zeolites (Ae-Y) as superior deacidification agents for paper. Their features such as the high surface area, adjustable alkali ion content, strength, good structural stability, and safety/non-toxicity or biocompatibility are very promising for preserving paper-based materials, as demonstrated by aging experiments carried out on both historical wood-pulp paper and modern hand-made bamboo paper samples. Through H 2 O-mediated dispersion of Ae-Y in target paper samples, the pH of the paper can be modified to a neutral or weakly basic state, and can be maintained for a long time even under harsh accelerated aging conditions. Meanwhile, the Ae-Y coating hardly alters the chromatic aberration and water wettability of papers. This new deacidifying agent does not trigger color changes in alkali-sensitive pigments (i.e., does not cause fading or blanching of pigments). Moreover, a systematic evaluation of the structure-performance relationship indicates the important roles of adequate accessible basic sites and controllable and mild basicity of Ae-Y in the long-term deacidification, anti-aging, and anti-fading effects exerted on paper relics. These findings not only shed light on the design of protective materials for paper-based cultural relics but also expand our knowledge on the deacidification and protection mechanisms of zeolites. Image 1 • Alkali ion-exchanged Y zeolites are proposed as deacidifying agents for paper. • They may be better alternatives in aqueous phase than generally used MgO and CaO. • Their superior performance is due to adequate accessible and mild basic sites. • The zeolite coatings hardly alter chromatic aberration and wettability of paper. • The zeolite coatings do not cause fading or blanching of alkali-sensitive pigments. [ABSTRACT FROM AUTHOR]

Light pollution (LP), induced by human activities, has become a crucial threat to biodiversity on the Tibetan plateau (TP), but few studies have explored its coverage and dynamics. In this study, we intended to measure the spatiotemporal patterns of LP on the TP from 1992 to 2018. First, we extracted the annual extent of LP from time-series nighttime light data. After that, we analyzed its spatiotemporal patterns at multiple scales and identified the natural habitats and the species habitats affected by LP. Finally, we discussed the main influencing factors of LP expansion on the TP. We found that the LP area increased exponentially from 1.2 thousand km2 to 82.8 thousand km2, an increase of nearly 70 times. In 2018, LP accounted for 3.2% of the total area of the TP, mainly concentrated in the eastern and southern areas. Several national key ecological function zones (e.g., the Gannan Yellow river key water supply ecological function zone) and national nature reserves (e.g., the Lalu Wetland National Nature Reserve) had a large extent of LP. The proportion of LP area on natural habitats increased from 79.6% to 91.4%. The number of endangered species with habitats affected by LP increased from 89 to 228, and more than a quarter of the habitats of 18 endangered species were affected by LP. We also discovered that roadways as well as settlements in both urban and rural areas were the main sources of LP. Thus, to lessen LP's negative effects on biodiversity, effective measures should be taken during road construction and urbanization on the TP. [ABSTRACT FROM AUTHOR]

[Display omitted] It is a Holy Grail to realize the goal-oriented synthesis of zeotype crystals via direct thermodynamic/kinetic control of crystallization in the simplest inorganic system. Especially, the most commonly used counter cations (i.e., Na+ and K+) are in turn believed to play merely the role of balancing charges and stabilizing frameworks, which make the simple ion-based morphology/porosity control remain big challenges. We re-examined the role of Na+ and K+ to fine-tune the classical/nonclassical crystallization process in a seed-induced system with the simplest composition (Si/Al sources, inorganic alkali, and H 2 O), and proposed an "ion switch" strategy. By analyzing the multiple growth curves, tracking the precursor evolution, and observing epitaxial crystallization behavior, a distinctive "ion switch"-worked nonclassical mechanism was uncovered. By the "ion switch" strategy, ZSM-5 mesocrystals were fine-regulated with diverse architecture from single crystal to nanocrystallite assembly and intracrystal mesopore-enriched crystal. Such simple ions-controlled crystallization was achieved through microstructure heterogeneity of zeolitic building-blocks triggered by different counterions and their corresponding assembly behavior from oriented attachment to random deposition. Furthermore, this protocol can be extended to a wider H 2 O/SiO 2 range, mixed Na+/K+ systems, and other alkali metal ions from Li+ to Cs+, and ZSM-5 mesocrystals with extended morphologies can be obtained. [ABSTRACT FROM AUTHOR]