Scalable fabrication of spherical particles at both the micro-and nanoscales is of significant importance for applications spanning optical devices, electronics, targeted drug delivery, biodevices, sensors, and cosmetics. However, current top-down and bottom-up fabrication methods are unable to provide the full spectrum of uniformly sized, well-ordered, and high-quality spheres due to their inherent restrictions. Here, a generic, scalable, and precisely controllable fabrication method is demonstrated for generating spherical particles in a full range of diameters from microscale to nanoscale. This method begins with a macroscopic composite multimaterial solid-state preform drawn into a fiber that defines precisely the initial conditions for the process. It is then followed by CO 2 laser heating to enable the transformation from a continuous fiber core into a series of homogeneous spheres via Plateau-Rayleigh capillary instability inside the fiber. This physical breakup method applies to a wide range of functional materials with different melting temperatures from 400 to 2400 K and 10 orders of difference in fiber core/cladding viscosity ratio. Furthermore, an ordered array of silicon-based whispering-gallery mode resonators with the Q factor as high as 7.1 × 10 5 is achieved, owing to the process induced ultrasmooth surface and highly crystalline nature.
We introduce a stirred self-stratified battery (SSB) that has an extremely simple architecture formed by a gravity-driven process. The oxidizing catholyte is separated from the reducing Zn anode by a liquid aqueous electrolyte layer. The Coulombic efficiency is always higher than 99%, even when stirring is applied to promote the charge-discharge rate. Moreover, the proposed SSB is intrinsically exempt from common failure mechanisms of other batteries; thus, its cycling stability is excellent, which is crucial for energy storage applications.
The growth of the chemical industry has brought tremendous challenges to chemical sensing technology. Chemical sensors based on metamaterials have great potential because of their label-free and non-destructive characteristics. However, metamaterials applied in chemical sensing have mainly been investigated from the measurement of sample concentration or the determination of the dielectric properties at a fixed frequency. Here we present a metamaterial integrated microfluidic (MIM) sensor for the multi-band sensing for dielectric property of chemicals, which is promising for the identification of chemicals. The MIM sensor mainly consists of multiple pair of high sensitive symmetrical double split-ring resonators (DSRRs) and meandering microfluidic channels with a capacity of only 4 μL. A dielectric model has been innovatively established and experimentally verified to accurately estimate the complex permittivity and thus realize the multi-band sensing of dielectric property of chemicals. With the increase in the number of resonators in the sensor, a dielectric spectrum like curve could be obtained for more detailed dielectric information. This work delivers a miniaturized, reusable, label-free and non-destructive metamaterial-microfluidic solution and paves a way of the multi-band sensing for dielectric property of chemicals.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.