Flexoelectric coefficient is a tetradic and its introduction enables centrosymmetric materials to exhibit piezoelectricity. However, the flexoelectric paradigm currently lacks a strategy to effectively tune the strain gradient for optimal electro-mechanical coupling. This study proposes a quantized collision model accessible through ionic irradiation technology to explore the flexoelectricity and precisely modulate the strain gradient.
View Article and Find Full Text PDFIn vertical farms, the supplementation of far-red light has been widely applied to regulate plant growth and development. However, the relative contribution of far-red to photosynthesis and plant growth in indoor production systems is not sufficiently quantified. This study quantify the photosynthesis and growth responses under different levels of supplemental far-red in lettuce using a 3D modelling approach.
View Article and Find Full Text PDFIt is of great significance to identify the pest species accurately and control it effectively to reduce the loss of agricultural products. The research results of this project will provide theoretical basis for preventing and controlling the spread of pests and reducing the loss of agricultural products, and have important practical significance for improving the quality of agricultural products and increasing the output of agricultural products. At the same time, it provides a kind of effective prevention and control measures for farmers, so as to ensure the safety and health of crops.
View Article and Find Full Text PDFDeveloping a ferroelectric tunnel junction with a robust polarization reversal is essential for errorless data storage, but it remains challenging since the second-order phase transition dominates the reversal and introduces intermediate states. This investigation has proposed a charge-gradient-induced ferroelectricity, which is featured with the first-order phase transition. As an order parameter, a charge-gradient-induced polarization is achieved by modulation of stoichiometric oxygen along the BiOSe/BiSeO bilayer during pulsed laser deposition.
View Article and Find Full Text PDFComput Math Methods Med
May 2021
With the increasing of depth and complexity of the convolutional neural network, parameter dimensionality and volume of computing have greatly restricted its applications. Based on the SqueezeNet network structure, this study introduces a block convolution and uses channel shuffle between blocks to alleviate the information jam. The method is aimed at reducing the dimensionality of parameters of in an original network structure and improving the efficiency of network operation.
View Article and Find Full Text PDFWe exploit a high-performing resistive-type trace oxygen sensor based on 2D high-mobility semiconducting Bi O Se nanoplates. Scanning tunneling microscopy combined with first-principle calculations confirms an amorphous Se atomic layer formed on the surface of 2D Bi O Se exposed to oxygen, which contributes to larger specific surface area and abundant active adsorption sites. Such 2D Bi O Se oxygen sensors have remarkable oxygen-adsorption induced variations of carrier density/mobility, and exhibit an ultrahigh sensitivity featuring minimum detection limit of 0.
View Article and Find Full Text PDFAt the mesoscopic level of commercial lithium ion battery (LIB), it is widely believed that the poor contacts between current collector (CC) and electrode materials (EM) lead to weak adhesions and large interfacial electric resistances. However, systematic quantitative analyses of the influence of the interfacial properties of CC are still scarce. Here, we built a model interface between CC and electrode materials by directly growing hierarchical graphene films on commercial Al foil CC, and we performed systematic quantitative studies of the interfacial properties therein.
View Article and Find Full Text PDFThe fast development of high-resolution electron microscopy (EM) demands a background-noise-free substrate to support the specimens, where atomically thin graphene membranes can serve as an ideal candidate. Yet the preparation of robust and ultraclean graphene EM grids remains challenging. Here we present a polymer- and transfer-free direct-etching method for batch fabrication of robust ultraclean graphene grids through membrane tension modulation.
View Article and Find Full Text PDFAtomically thin oxychalcogenides have been attracting intensive attention for their fascinating fundamental properties and application prospects. Bi O Se, a representative of layered oxychalcogenides, has emerged as an air-stable high-mobility 2D semiconductor that holds great promise for next-generation electronics. The preparation and device fabrication of high-quality Bi O Se crystals down to a few atomic layers remains a great challenge at present.
View Article and Find Full Text PDFACS Appl Mater Interfaces
August 2018
It is a widely used strategy to enhance gas sensor sensitivity by improving its surface area, but this process, including bonding the sensing block into a device substrate, needs complex manipulations. This work shows a concept of creating adsorption active sites, in which an SnO layer (6.85 nm thin) is directly coated on a triangle array substrate to be of an ensemble of triangular convex adsorption active sites (TCAASs).
View Article and Find Full Text PDFChempluschem
August 2018
High sensitivity imposes strict requirements on a sensing platform, for which nanostructured arrays are promising candidates. The template-assisted method is an effective strategy to prepare various nanostructured arrays, which are widely developed for different sensing applications. Herein, nanostructured array based sensing platforms prepared from four widely used templates, a colloidal monolayer, anodic aluminum oxide, block copolymer, and a nanoimprint mold, are reviewed.
View Article and Find Full Text PDFACS Appl Mater Interfaces
April 2018
Adsorption-induced change of carrier density is presently dominating inorganic semiconductor gas sensing, which is usually operated at a high temperature. Besides carrier density, other carrier characteristics might also play a critical role in gas sensing. Here, we show that carrier mobility can be an efficient parameter to dominate gas sensing, by which room-temperature gas sensing of inorganic semiconductors is realized via a carrier mobility-dominated gas-sensing (CMDGS) mode.
View Article and Find Full Text PDFPlasmonic nanostructures have been widely incorporated into different semiconductor materials to improve solar energy conversion. An important point is how to manipulate the incident light so that more light can be efficiently scattered and absorbed within the semiconductors. Here, by using a tunable three-dimensional Au pillar/truncated-pyramid (PTP) array as a plasmonic coupler, a superior optical absorption of about 95% within a wide wavelength range is demonstrated from an assembled CdS/Au PTP photoanode.
View Article and Find Full Text PDFA new general method for the fabrication of a reduced graphene oxide (rGO)-based ordered monolayer macroporous film composed of a layer of closely arranged pores is introduced. Assisted by the polystyrene microsphere monolayer colloid crystal by a simple solution-heated method, pure rGO, rGO-SnO2, rGO-Fe2O3, and rGO-NiO composite monolayer ordered porous films were examplarily constructed on the curved surface of a ceramic tube widely used in gas sensors. The rGO-oxide composite porous films could exhibit much better sensing performances than those of the corresponding pure oxide films and the composite films without the ordered porous structures in detecting ethanol gas.
View Article and Find Full Text PDFA new graphene-based composite structure, monolayer-ordered macroporous film composed of a layer of orderly arranged macropores, was reported. As an example, SnO2-reduced graphite oxide monolayer-ordered macroporous film was fabricated on a ceramic tube substrate under the irradiation of ultra-violet light (UV), by taking the latex microsphere two-dimensional colloid crystal as a template. Graphite oxide sheets dispersed in SnSO4 aqueous solution exhibited excellent affinity with template microspheres and were in situ incorporated into the pore walls during UV-induced growth of SnO2.
View Article and Find Full Text PDFA new photochemistry-based method was introduced for fabricating SnO2 monolayer ordered porous films with size-tunable surface pores on ceramic tubes used for gas sensors. The growth of the spherical pore walls was controlled by two times irradiation of the ultraviolet light using polystyrene microsphere two-dimensional colloidal crystal as a template. The surface pore size of the final obtained porous films was well tuned by changing the second irradiation time rather than replacing the template microspheres.
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