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To meet the increasing need for outdoor personal thermal management (PTM) since the intensified global warming, radiative cooling (RC) textiles with tunable solar reflectivity and mid-infrared emissivity/transmissivity attributes can dynamically adjust the microenvironment of the human body to provide a cooling effect without consumption of electrical energy, in contrast to the traditional heat preservation function of commercial clothes. In this review, we summarize recent advances in RC textiles from basic mechanisms, construction methods to emerging applications. The underlying mechanisms of optical absorption/reflection and heat emission properties and typical efficient structures are first discussed to comprehend the principles of RC techniques. The corresponding construction strategies for modifying textile materials and structures for improved passive cooling performance are then highlighted. The various applications of RC textiles are also reviewed to demonstrate their practicability and versatility, such as smart clothing, object cooling, enhanced electricity generation, etc. Eventually, we will give a brief outlook on the current challenges and future development of RC textiles. This review intends to provide a better understanding of RC techniques for functional textile design and fabrication. [ABSTRACT FROM AUTHOR]

Crown ethers demonstrate significant conformational flexibility and rotational symmetry, rendering them invaluable in the realms of supramolecular chemistry and crystal engineering. These unique natures facilitate the construction of supramolecular crystals of crown ethers, characterized by disorder‐order phase transitions, imparts unique properties that hold promise for diverse applications across multiple fields. In this study, four supramolecular compounds, namely [Na(15‐crown‐5)]BF4 (1), [Na(18‐crown‐6)]BF4⋅H2O (2), [K(15‐crown‐5)]BF4 (3) and [K(18‐crown‐6)]BF4⋅H2O (4) were synthesized and characterized by microanalysis, thermogravimetric analysis, differential scanning calorimetry and powder X‐ray diffraction techniques. Herein, 15‐crown‐5 and 18‐crown‐6 correspond to 1,4,7,10,13‐pentaoxacyclopentadecane and 1,4,7,10,13,16‐hexaoxacyclooctadecane, respectively. It was observed that the crystal structure, phase transition, and dielectric properties of these supramolecular compounds are significantly influenced by the size of the crown‐ether rings. The research extensively discussed the correlation between the coordination mode of metal ions of K+ or Na+ with crown ethers, the compatibility between metal ions and crown‐ether rings in terms of size, and the effects of crown‐ether disorder on dielectric permittivity during phase transitions. Our discoveries hold significant implications for the design and development of crown‐ether supramolecular functional materials. [ABSTRACT FROM AUTHOR]

Residual yolk is assumed to be an important source of energy and nutrients during early life in nonmammalian amniotes. Available data show that the mean size of residual yolk is far smaller in lizards than in turtles, snakes, crocodiles, and birds, raising a question of whether residual yolk is of functional significance in lizards. Here, we compared data from 26 lizard species with those from other nonmammalian amniotes to test the hypothesis that residual yolk is functionally less significant in species producing more fully developed offspring. In our sample, species mean offspring water contents ranged from 73% to 84% of body wet mass; species mean proportions of carcass dry mass, fat-body dry mass, and residual yolk dry mass to offspring dry mass ranged from 84% to 99%, 0% to 5.0%, and 0% to 14.4%, respectively. Lizards are, on average, more fully developed at hatching or birth than snakes, as revealed by the fact that the mean proportion of carcass dry mass to body dry mass and offspring water contents were both higher in lizards than in snakes. We conclude that the functional significance of residual yolk during early life is generally less evident in lizards. Even in the lizards where residual yolk is of potential functional significance, this portion of yolk contributes little, if any, to postembryonic growth. Future work could usefully collect data across a wider spectrum of reptile taxa to establish a precocial–altricial continuum and test the hypothesis that species with a smaller amount of residual yolk are closer to the precocial end of the continuum. [ABSTRACT FROM AUTHOR]