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Obtaining safe and affordable water free from bio-contaminants is a critical global issue. Filtration using polymer membranes with nanopores is a significant method for water purification. Here, we demonstrate the fabrication of water-treatment membranes with ordered nanochannels, exhibiting significant virus removal properties, by fixing the assembled structures of ionic liquid-crystalline molecules via photopolymerization. Nanostructured water-permeable membranes are prepared from ionic liquid-crystalline smectic compounds composed of a rod-shaped rigid core to form two-dimensional nanochannels. The removal of viruses, including inactivated SARS-CoV-2, in a virus cocktail solution is investigated. Tuning of the smectic assembled structures is discussed from the perspective of self-assembled molecular structures. In addition, the effects of the ionic channel morphology on water permeability are examined. [ABSTRACT FROM AUTHOR]

Structural colouration observed in antimony phosphate nanosheet suspensions has been known for two decades, but the stability of their inner structures has not been a topic in colloidal nanosheet systems. In this study, we investigate the time evolution of structures in suspension using UV-visible spectrometry and small-angle X-ray scattering. Here, we report that antimony phosphate nanosheet systems re-organise their inner structures, especially at lower concentrations (isotropic or biphasic region), and that the basal spacing decreases with time after sample preparation, although the evolution speed depends on the sample concentration. The stability of the inner structure of the suspension is essential for their application as structural colour materials in sensors and colourants.

Photonic crystals, characterized by their periodic structures, have been extensively studied for their ability to manipulate light. Typically, the development of 2D photonic crystals requires either sophisticated equipment or precise orientation of spherical nanoparticles. However, liquid-crystalline (LC) materials offer a promising alternative, facilitating the formation of periodic structures without the need for complex manipulation. Despite this advantage, the development of 2D photonic periodic structures using LC materials is limited to a few colloidal nanodisk liquid crystals. Herein, 2D photonic colloidal liquid crystals composed of biomineral-based nanorods and water is reported. The soft photonic materials with 2D structure by self-assembled LC colloidal nanorods are unique and a new class of photonic materials different from conventional solid 2D photonic materials. These colloids exhibit bright structural colors with high reflectance (>50%) and significant angular dependency. The structural colors are adjusted by controlling the concentration and size of the LC colloidal nanorods. Furthermore, mechanochromic hydrogel thin films with 2D photonic structure are developed. The hydrogels exhibit reversible mechanochromic properties with angular dependency, which can be used for an advanced stimuli responsible sensor., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Structural color colloidal sols of perovskite nanosheets were synthesized and were immobilized in a polymer hydrogel film by in situ photopolymerization, leading to a novel mechanochromic material. Visible absorption spectroscopy, polarized optical microscopy and small-angle X-ray scattering revealed that the nanosheets are aligned parallel to the film surface with the periodic distance of up to ca. 300 nm, giving the structural color tunable over full color range. The present structural color gel showed reversible mechanochromic response that detects weak stress of 1 kPa with the quick response time less than 1 ms as well as high mechanical toughness (compressive breaking stress of up to 3 MPa). These excellent properties are suitable for applications for mechano-sensors and displays., (© 2021 Wiley-VCH GmbH.)

The Addiction Severity Index (ASI) is a frequently used clinical and research instrument that collects data from substance abusers in seven problem areas: medical, employment, alcohol, drug use, legal, family-social functioning, and psychiatric status. In each area, the ASI provides a composite score and severity rating that estimate the seriousness of the problem and the client's need for treatment. In the present study, we investigated the reliability and validity of the Japanese version of the ASI (ASI-J). One hundred and eleven subjects with a history of drug abuse were interviewed with a test battery including the ASI with informed consent. This revealed that: (a) the problem areas were independent of each other, underscoring the need for multidimensional assessment, (b) the inter-rater correlation of severity ratings in each area ranged from 0.68 to 0.99, and Cronbach's alpha coefficient for the items used for the composite score in each area ranged from 0.57 to 0.86, indicating their reliability with the exception of the drug and employment areas, and (c) several composite scores were significantly correlated with the drug craving levels assessed by a visual analogue scale, the abstinence period, mental health, and/or relapse, supporting their concurrent and predictive validity. These results suggest that the ASI-J has acceptable reliability and validity.