Thouin, Félix; Neutzner, Stefanie; Cortecchia, Daniele; Dragomir, Vlad Alexandru; Soci, Cesare; Salim, Teddy; Lam, Yeng Ming; Leonelli, Richard; Petrozza, Annamaria; Kandada, Ajay Ram Srimath; Silva, Carlos
Stable biexcitons in two-dimensional metal-halide perovskites with strong dynamic lattice disorder
With strongly bound and stable excitons at room temperature, single-layer, two-dimensional organic-inorganic hybrid perovskites are viable semiconductors for light-emitting quantum optoelectronics applications. In such a technological context, it is imperative to comprehensively explore all the factors --- chemical, electronic and structural --- that govern strong multi-exciton correlations.…
Structural and Dynamic Heterogeneity in the Amorphous Phase of Poly(l,l-lactide) Confined at the Nanoscale by the Coextrusion Process
Nassar, Samira Fernandes; Domenek, Sandra; Guinault, Alain; Stoclet, Gregory; Delpouve, Nicolas; Sollogoub, Cyrille
Multi-nanolayered polystyrene/poly(l,l-lactide) (PS/PLLA) films were obtained by the layer-multiplying coextrusion process, with an individual PLLA layer thickness as thin as 20 nm. The confinement of the amorphous PLLA induced a change in the molecular mobility, evidenced by a drop of the cooperative rearranging region (CRR) size at the glass transition.…
Structural analysis of mtEXO mitochondrial RNA degradosome reveals tight coupling of nuclease and helicase components
Razew, Michal; Warkocki, Zbigniew; Taube, Michal; Kolondra, Adam; Czarnocki-Cieciura, Mariusz; Nowak, Elzbieta; Labedzka-Dmoch, Karolina; Kawinska, Aleksandra; Piatkowski, Jakub; Golik, Pawel; Kozak, Maciej; Dziembowski, Andrzej; Nowotny, Marcin
The mitochondrial RNA degradosome (mtEXO) plays an essential role in the regulation of mitochondrial gene expression and is composed of the 3′-to-5′ exoribonuclease Dss1 and the helicase Suv3. Here the authors present the RNA bound mtEXO crystal structure and give insights into its…
Solvent-Controlled Assembly of Aromatic Glutamic Dendrimers for Efficient Luminescent Color Conversion
Xing, Pengyao; Yang, Chaolong; Wang, Yang; Phua, Soo Zeng Fiona; Zhao, Yanli
A binary supramolecular system where self-sorting and coassembly behavior can be switched by changing the solvent polarity is hereby reported. Glutamic dendron is separately conjugated with pyrene and naphthalimide luminophores through an alkyl spacer. The resulting structurally similar building units can self-assemble into one-dimensional micro/nanostructures with hexagonal and lamellar packing,…
Shape memory property and underlying mechanism by the phase separation control of poly(ϵ-caprolactone)/poly(ether-b-amide)
Liu, Xinran; Huang, Miaoming; Zhu, Ping; Dong, Siyuan; Dong, Xia; Wang, Dujin
In this work, a poly(ϵ-caprolactone)/poly(ether-b-amide) blend with weight ratio 35/65 was prepared by solution mixing and compression molding. A simple and sensible method to control the phase separation structure was introduced by adjusting the temperature and time for the process of phase separation. Samples with obviously different morphology were obtained…
Semicrystalline Hydrophobically Associated Hydrogels with Integrated High Performances
Wei, Dandan; Yang, Jia; Zhu, Lin; Chen, Feng; Tang, Ziqing; Qin, Gang; Chen, Qiang
Hydrophobically associated hydrogels (HA gels) are one of most extensively investigated high strength hydrogels. Semicrystalline HA gels, prepared by micellar copolymerization, show high strength and notable functionalities of self-healing and shape-memory. However, the hydrophobic comonomers in these semicrystalline HA gels are usually limited to the long alkyl length monomers…
Sensitivity of Polymer Crystallization to Shear at Low and High Supercooling of the Melt
Rhoades, Alicyn M.; Gohn, Anne M.; Seo, Jiho; Androsch, René; Colby, Ralph H.
Flow-induced crystallization (FIC) is a dominant mechanism of polymer self-assembly, but the process is poorly understood at high supercooling and under fast cooling conditions because of structural rearrangements that occur during slow heating and cooling conditions typically used for investigation. Incorporating fast-scanning chip calorimetry techniques, the influence that specific amounts…
Self-Assembled 3D Helical Hollow Superstructures with Enhanced Microwave Absorption Properties
Yang, Yang; Zhang, Jianqi; Zou, Wenjun; Wu, Sai; Wu, Fan; Xie, Aming; Wei, Zhixiang
Helical structures at different scales endow functional materials with special optical, electrical, and magnetic properties. However, methods for constructing and regulating single-handed helicity, particularly complex 3D hierarchical structures, remain limited. In this study, co-self-assembly process combined with emulsion droplets is used to produce the various well-defined 3D hollow…
Retardance of Form II to Form I Transition in Polybutene-1 at Late Stage: A Proposal of a New Mechanism
Qiao, Yongna; Wang, Hai; Men, Yongfeng
The retardation of polybutene-1 form II to form I transition in the late stage has been investigated by means of time-resolved wide-angle X-ray diffraction. Form II samples with different lamellar thickness and constituent in amorphous phase were generated via varying crystallization temperature and molecular weight and aged at room temperature…
Rapid, Acid-Free Synthesis of High-Quality Graphene Quantum Dots for Aggregation Induced Sensing of Metal Ions and Bioimaging
Nair, Raji V.; Thomas, Reny Thankam; Sankar, Vandana; Muhammad, Hanif; Dong, Mingdong; Pillai, Saju
Graphene quantum dots (GQDs) are zero-dimensional materials that exhibit characteristics of both graphene and quantum dots. Herein, we report a rapid, relatively green, one-pot synthesis of size-tunable GQDs from graphene oxide (GO) by a sonochemical method with intermittent microwave heating, keeping the reaction temperature constant at 90 °C. The GQDs…