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We studied the structure of a helical nano-filament of the B4 phase in mixtures of a cholesteric liquid crystal mixture and a bent-core molecule using a resonant soft X-ray scattering (RSoXS) technique. In this system, nanophase separation occurs and it was already found that an unexpected new functional chiral smectic structure in the rod-like molecule rich region is constructed by the strong interaction between bent-core and rod-like molecules. In this paper, we focused on the structure of the helical filament in the bent-core liquid crystalline molecule rich region in this mixing system, and it was found that the pitch of the helical filament decreases and the coherence of the helical structure increases.
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http://dx.doi.org/10.1039/d2ra03316j | DOI Listing |
Phys Rev Lett
August 2025
Huazhong University of Science and Technology, Wuhan National Laboratory for Optoelectronics and School of Physics, Wuhan 430074, China.
We propose a scheme for retrieving the ultrafast valley polarization (VP) dynamics in two-dimensional hexagonal materials via attosecond circular dichroism (CD) transient absorption spectroscopy. This approach builds on the CD transition between the first and higher conduction bands induced by the circularly polarized probe pulses. The population imbalance at nonequivalent valleys in the first conduction band is proportionally mapped onto the difference in absorption coefficients of two probe pulses with opposite helicities, supporting an unprecedented quantitative retrieval of the corresponding VP dynamics with subfemtosecond time resolution.
View Article and Find Full Text PDFACS Nano
September 2025
CINBIO and Departamento de Química Orgánica. Campus Lagoas-Marcosende, Universidade de Vigo, Vigo E-36310, Spain.
Archimedean spirals are architectural motifs that are found in nature. The facial asymmetry of amphiphilic molecules or macromolecules has been a key parameter in the preparation of these well-organized two-dimensional nanostructures in the laboratory. This facial asymmetry is also present in the helical grooves of chiral helical substituted poly(phenylacetylene)s (PPAs) and poly(diphenylacetylene)s (PDPAs), making them excellent candidates for self-assembly into 2D Archimedean nanospirals or nanotoroids.
View Article and Find Full Text PDFmBio
September 2025
School of Biological Sciences, University of Auckland, Auckland, New Zealand.
The rotation of the bacterial flagellum is powered by the MotAB stator complex, which converts ion flux into torque. Despite its central role in flagellar function, the evolutionary origin and structural diversity of this system remain poorly understood. Here, we present the first comprehensive phylogenetic and structural characterization of MotAB and its closest non-flagellar homologs.
View Article and Find Full Text PDFAnal Chem
September 2025
Department of Chemistry, Wuhan University, Wuhan 430072, China.
Three-dimensional printing (3DP) technology enables the flexible fabrication of integrated monolithic microextraction chips for high-throughput sample pretreatment. Meanwhile, the extraction performance of 3DP-based channels is largely limited by printer resolution and the commercially available printing materials. In this work, a 3DP array monolithic microextraction chip (AMC) was fabricated by integrating 26-array helical monolithic microextraction channels for sample pretreatment and 52-array gas valves for fluid control.
View Article and Find Full Text PDFBeilstein J Org Chem
August 2025
College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, 310058, China.
Beyond the conventional carbon-centered chirality, catalytic asymmetric transformations of isocyanides have recently emerged as a powerful strategy for the efficient synthesis of structurally diverse scaffolds featuring axial, planar, helical, and inherent chirality. Herein, we summarize the exciting achievements in this rapidly evolving field. These elegant examples have been organized and presented based on the reaction type as well as the resulting chirality form.
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