Biobased Polymers Enabling the Synthesis of Ultralong Silver Nanowires and Other Nanostructures

Nano Letters, Journal Year: 2024, Volume and Issue: 24(45), P. 14381 - 14388

Published: Oct. 30, 2024

Conventional polyol synthesis of silver nanowires has exclusively relied on polyvinylpyrrolidone (PVP), a nonbiodegradable polymer with no viable alternatives. The underlying reaction mechanism remains unclear. Herein, we discovered new sustainable solution by employing biobased cellulose derivatives, including hydroxyethyl (HEC), as effective substitutes for PVP. Under mild conditions (125 °C, ambient pressure), HEC facilitates the growth ultralong (>100 μm) from penta-twinned seeds through four-stage kinetic process. Theoretical calculations further reveal that is physiosorbed onto surfaces, while presence bromide ions (Br–) evolution into nanowires. By varying halide ion concentrations and substitution in different successfully synthesized nanostructures additional intriguing morphologies, quasi-spherical nanoparticles, bipyramids, nanocubes. Furthermore, transparent conductive films fabricated demonstrated superior performance compared to those made PVP-synthesized

Language: Английский

A Combined Raman Spectroscopy and Chemometrics Study of the Interaction of Water-Soluble Polymers with Microorganisms

Spectroscopy Journal, Journal Year: 2025, Volume and Issue: 3(1), P. 7 - 7

Published: Feb. 22, 2025

Optical spectroscopic methods such as Raman spectroscopy offer several advantages for the analysis of water-soluble polymers (WSPs). There is often no need complex sample preparation, and measurements are usually rapid, mostly non-destructive harmful chemicals required. In this work, we investigated WSPs their interaction with bacteria using methods. We analyzed four different WSPs, each three molar masses, in solid form microscopy, aqueous solutions another system designed cuvettes, to train predictive models concentration determination. Thus, were able show both high potential these approaches, especially fast easy investigations qualitatively quantitatively, well limitations. Furthermore, chose one masses tested polymer carry out extensive Escherichia coli Enterococcus faecium, revealed that bacterial cells exposed exhibited distinguishable spectral characteristics compared those not contact polymers. Using microscopy combined partial least squares discriminant (PLS-DA), effectively distinguished between groups. Further chemometric indicated polymer-induced modifications cell membranes. While differentiation may partly reflect interactions at membrane level, it could also correspond shifts growth phases. Together, findings suggest a interplay exposure physiological states.

Language: Английский

From image-level to pixel-level labeling: A weakly-supervised learning method for identifying aquaculture ponds using iterative anti-adversarial attacks guided by aquaculture features

International Journal of Applied Earth Observation and Geoinformation, Journal Year: 2024, Volume and Issue: 132, P. 104023 - 104023

Published: July 15, 2024

Aquaculture mapping is essential for monitoring and managing aquaculture resources. However, accurately geotargeting individual ponds from medium-resolution remote sensing imagery remains challenging, convolutional deep learning methods identifying require labor-intensive pixel-level annotations. This paper presents a novel weakly-supervised method to derive labels image-level annotations ponds. Our approach uses iterative anti-adversarial attacks refine localization results multi-scale class activation maps (CAMs). The improved integrates two regularization guided by features form joint loss function adversarial samples: discriminative water region suppression non-aquaculture suppression. We also propose an feature termed CFNDWI constrain the generate high-quality pseudo-labels. As result, pseudo-labels are used train semantic segmentation networks evaluated performance of our using commonly-used backbones on 10 m Sentinel-2 imagery. achieves Intersection over Union (IoU) values 0.618–0.655 pseudo-label generation, IoU 0.664–0.708 segmentation, outperforming state-of-the-art public datasets. effectiveness each module was testified through ablation experiments. leverages knowledge-driven guide data-driven process, addressing lack datasets model training. code implementing will be accessible at https://github.com/designer1024/WSLM-AQ.

Language: Английский