Based on the combination of the unique features of both polyionic liquids and spherical colloidal crystals, a new class of inverse opaline spheres with a series of distinct properties was fabricated. It was found that such photonic spheres could not only be used as stimuli-responsive photonic microgels, but also serve as multifunctional microspheres that mimic the main characteristics of conventional molecules, including intrinsic optical properties, specific molecular recognition, reactivity and derivatization, and anisotropy.

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Freshwater capture fisheries are globally essential for food security and aquatic biodiversity conservation. The Yangtze River Basin is the third longest and one of the most human-influenced drainage basins worldwide. Since the founding of P. R.China in 1949, this large river system has suffered increasing human perturbation and its sustainable development is now severely challenged. Meta-analysis showed that Yangtze River fisheries have experienced an extraordinary process of utilization-over-exploitation-protection during the past 70 years, to an extent that other globally important rivers may never have encountered. Its fisheries appear to have collapsed over the past four decades, with yield decreasing to only 25% of an historical peak of 400,000 metric tonnes in the late 1950s. Endemic, migratory and rare fishes have been highly threatened with obvious changes in fish community structure and aquatic biodiversity. Anthropogenic activities, including impoundment of water in dams, discharge of pollutants and riverine modification for vessel navigation, have caused large decreases in fisheries yields. Projections from surplus production modelling showed potential for improvement under fishing ban scenarios, but without any prospect for full recovery to historical stock status. This study revealed that the change in fisheries resources was dominated by the social-ecological watershed system, and an integrated approach to river basin management is warranted. Better management of freshwater ecosystems to integrate food security with biodiversity conservation is urgently needed throughout the world, and the changes evident in the Yangtze River fish populations can serve as an informative global reference. K E Y W O R D Sbiodiversity conservation, China, fishing ban, food security, human impact, inland fishery

A convenient and cost-effective chemical approach was developed to fabricate Au aggregates with uniform 1 nm nanogaps through the assembly of cucurbit[n]urils with Au colloids. Cucurbit[n]urils located in the nanogap region can be used as a useful SERS hot-spot nanocontainer to realize the SERS enhancement of an "inert" molecule up to 10(9).

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In this paper, we present a new strategy for efficiently enhancing fluorescence, based on the coupling of surface plasmons of metal particles with optical properties of colloidal photonic crystals. It is found that such coupling can effectively improve the near-field effect and induced plasmon effect of metal particles but also be favorable for the extraction of the emission, collectively leading to a further significant enhancement of metal-enhanced fluorescence. Finite-difference time-domain (FDTD) simulation proved the related enhancement mechanism for the designed hybrid system. As a proof of concept, an enhancement factor up to 260-fold has been experimentally achieved by using rhodamine B as test molecule, which greatly transcends those of two individual plasmonic and photonic components and is also much larger than the simple plus effects of the two components.

Because vanadium pentoxide (V2O5) is the only oxide that shows both anodic and cathodic coloration electrochromism, the reversible lithium ion insertion/extraction processes in V2O5 lead to not only reversible optical parameter changes but also multicolor changes for esthetics. Because of the outstanding electrochemical properties of V2O5 nanofibers, they show great potential to enhance V2O5 electrochromism. However, the development and practical application of V2O5 nanofibers are still lacking, because traditional preparation approaches have several drawbacks, such as multiple processing steps, unsatisfactory electrical contact with the substrate, expensive equipment, and rigorous experimental conditions. Herein, we first report a novel and convenient strategy to prepare grass-like nanofiber-stacked V2O5 films by a simple annealing treatment of an amorphous, three-dimensionally ordered macroporous vanadia film. The V2O5 nanofiber grassland exhibits promising transmittance modulation, fast switching responses, and high color contrast because of the outstanding electrochemical properties of V2O5 nanofibers as well as the high Li-ion diffusion coefficients and good electrical contact with the substrate. Moreover, the morphology transformation mechanism is investigated in detail.

Three-dimensionally ordered macroporous (3DOM) vanadium oxide film was fabricated by anodic deposition of vanadium oxide into colloidal crystal template. The as-prepared films were investigated by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS). The electrochemical and electrochromic behaviors of the films were studied in 1.0 M LiClO 4 -propylene carbonate solution. Because of the larger surface area and shorter diffusion distance, the 3DOM film exhibited better electrochromic performance than the dense film prepared without the template. The 3DOM film exhibited multicolor changes (yellow, green and black) in the voltage window from +1 to À1 V with a high transmittance modulation of ca. 34% at 460 nm and high switching speed (1.5 s for coloration and 2.1 s for bleaching). Cyclic voltammetry (CV) and chronoamperometry measurements showed that the 3DOM structure is beneficial for Li + diffusion in vanadium oxide films. An ITO/vanadia/gel/PEDOT:PSS/ITO electrochromic device was assembled, and the device showed multicolor changes with fast switching speed (3.5 s for anodic coloration and 3.4 s for cathodic coloration) and good cycling stability.