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The hierarchical self‐assembly process opens up great potential for the construction of nanostructural superlattices. Precise regulation of self‐assembled superlattices, however, remains a challenge. Even when the primary molecules are precise, the supramolecular motifs (or secondary building blocks) can vary dramatically. In the present work, we propose the concept of unimolecular nanoparticles (UMNPs). The UMNPs act as the supramolecular motif and directly pack into the superlattices. A highly branched giant molecule is presented. We systematically explore its conformations and the superlattice of this giant molecule. Moreover, intriguing complex phases are discovered when blending this UMNP with other conventional giant molecules. These binary mixtures provide direct evidence to support our previously proposed self‐sorting process in the self‐assembly of "soft alloys". The concept of UMNPs offers a unique approach toward more precise regulation of self‐assembled superlattices in soft matter. [ABSTRACT FROM AUTHOR]

Elongated microvoids, internal fibrillar structure, and edge scattering from both surface refraction cause an equatorial streak in small angle X-ray scattering. A model for analyzing the edge scattering of fibers is proposed. Simulation results indicate that the intensity of edge scattering from surface refraction of a cylindrical fiber is strong and makes an important contribution to the equatorial streak. Two factors influence edge scattering intensity. One is the sample-to-detector distance (D); edge scattering intensity increases with increasing D. The equatorial streak becomes weak when D is shortened. The other factor is the refraction index. Edge scattering intensity increases as the real component of the refraction index decreases. In experiment, weak or even no equatorial streaks were found for samples measured in a roughly index-matching fluid. Edge scattering can be eliminated or weakened, and it can be calculated by comparing the intensities of a cylindrical fiber when it is measured in air and in index-matching fluid. The simulation data are basically in agreement with the experimental data. [ABSTRACT FROM AUTHOR]

The selective removal and immobilization of uranyl ions from aqueous solutions is essential for the sustainable development of nuclear energy. Herein, a robust lanthanide‐organic framework material (IHEP‐24) is developed for simultaneous fluorescence sensing, selective adsorption, and photocatalytic reduction of uranium, integrating three different functions in one material. The confined space formed by the coordination assembly of viologen derivative ligands and metal‐oxygen clusters can act as precise recognition sites for uranyl, allowing IHEP‐24 to efficiently detect and capture uranyl ions. In addition, the presence of a viologen‐based radical ligand enables IHEP‐24 to a further photocatalytic reduction of the adsorbed uranyl to amorphous UO2. The mechanisms of adsorption and photocatalysis are revealed by batch experiments, photoelectrochemical characterizations, and theoretical calculations. This study provides a reference for the construction of robust multi‐functional MOF materials and also provides support for the deep removal and immobilization of radionuclides from aqueous solution. [ABSTRACT FROM AUTHOR]

Regenerated cellulose/polyacrylamide (RC/PAAm) double network (DN) hydrogels are composed of cellulose crosslinked by epichlorohydrin (ECH) and chemical‐crosslinked PAAm. The prepared RC/PAAm DN hydrogels present enhanced strength, good shape recovery property, excellent energy dissipation properties, decreased equilibrium water content, and low equilibrium swelling ratio (SR). The compressive strength and modulus of RC/PAAm hydrogel are about 4.3 and 11.5 times compared to that of RC hydrogel, respectively. Intriguingly, the chemical crosslinking between ECH and cellulose chains could increase the distance between cellulose chains. Consequently, the increasing molar ratio of ECH to glucose leads to larger SRs and decreased mechanical strength of the hydrogels. Additionally, higher PAAm contents lead to more densely crosslinked networks, and thus decreasing the SRs and improving the mechanical strength of the hydrogels. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47811. [ABSTRACT FROM AUTHOR]

Long polymer chains are admittedly beneficial for formation of flow‐induced shish‐kebabs, but up to now, the role of pressure, one major polymer processing parameter, in flow‐induced shish‐kebab is not touched. In the current work, bulk polyethylene (PE) and blend of 98 wt% PE and 2 wt% linear ultra‐high molecular weight polyethylene (LUHMPE/PE) were used as model polymers. Utilizing the pressuring and shearing device (PSD), the combined effect of pressure and long chains on flow‐induced shish‐kebab was revealed for the first time. Under a pressure of 50 MPa, there was no trace of shish‐kebab over the entire range of applied shear rates (0.5‐28.3 s−1). As the pressure increased to 75 MPa, shish‐kebab was induced by flow at 28.3 s−1 for PE, while shish‐kebab appeared in LUHMPE/PE blends at 15.7 s−1. Undoubtedly, the pressure significantly facilitated the formation of shish‐kebab and revealed a synergistic effect on flow‐induced shish‐kebab when cooperating with long chains. Our research not only demonstrates the importance of pressure conditions in flow‐induced crystallization, but also provides more valuable data for actual processing. [ABSTRACT FROM AUTHOR]

Abstract: Small angle X-ray scattering (SAXS) studies were carried out in Shanghai Synchrotron Radiation Facility (SSRF) to study the effect of addition of TiB2 particles on the melt structures of Al-15 wt% Cu. It was found that doping with TiB2 particles could dramatically reduce the sizes of the melt aggregates at temperatures ranging from the melting point to 800 °C. The results show that the aggregates in the Al–Cu melt present mass fractal characteristics and distribution of incompact 3D flocs. [Copyright &y& Elsevier]

The quasiperiodic structures in metal alloys have been known to depend on the existence of icosahedral order in the melt. Among different phases observed in intermetallics, decagonal quasicrystal (DQC) structures have been identified in many glass-forming alloys yet remain inaccessible in bulk-state condensed soft matters. Via annealing the mixture of two giant molecules, the binary system assemblies into an axial DQC superlattice, which is identified comprehensively with meso-atomic accuracy. Analysis indicates that the DQC superlattice is composed of mesoatoms with an unusually broad volume distribution. The interplays of submesoatomic (molecular) and mesoatomic (supramolecular) local packings are found to play a crucial role in not only the formation of the metastable DQC superlattice but also its transition to dodecagonal quasicrystal and Frank-Kasper σ superlattices., Competing Interests: The authors declare no competing interest., (Copyright © 2022 the Author(s). Published by PNAS.)