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Two-dimensional (2D) materials including graphene, transition metal dichalcogenides, black phosphorus, MXenes, and semimetals have attracted extensive and widespread interest over the past years for their many intriguing properties and phenomena, underlying physics, and great potential for applications. The vast library of 2D materials and their heterostructures provides a diverse range of electrical, photonic, mechanical, and chemical properties with boundless opportunities for photonics and plasmonic devices. The infrared (IR) regime, with wavelengths across 0.78 μm to 1000 μm, has particular technological significance in industrial, military, commercial, and medical settings while facing challenges especially in the limit of materials. Here, we present a comprehensive review of the varied approaches taken to leverage the properties of the 2D materials for IR applications in photodetection and sensing, light emission and modulation, surface plasmon and phonon polaritons, non-linear optics, and Smith–Purcell radiation, among others. The strategies examined include the growth and processing of 2D materials, the use of various 2D materials like semiconductors, semimetals, Weyl-semimetals and 2D heterostructures or mixed-dimensional hybrid structures, and the engineering of light–matter interactions through nanophotonics, metasurfaces, and 2D polaritons. Finally, we give an outlook on the challenges in realizing high-performance and ambient-stable devices and the prospects for future research and large-scale commercial applications.

A broadband vortex beam generator provides a promising solution for various applications. Since the space-charge wave of the free-electron bunch inherently covers a wide frequency range, the free-electron-driven devices can be utilized to generate broadband radiation. This work presents a wideband tunable multi-mode vortex beam generator based on the Smith–Purcell radiation (SPR) from a helical grating. The generated broadband vortex radiation presents prominent flexibility in the manipulation of frequency, topological charge, and radiation direction. The frequency range and the topological charge depend on the operating harmonic order, operating voltage, and structural parameters. The radiation direction varies with the operating frequency and covers a wide range in each band. Moreover, the proposed principle can be scaled to the terahertz frequency band. This work advances the application of the vortex beam in the millimeter wave-terahertz communication system.

AbstractThis study examined the impact of the preceding boreal summer (June–August) North Atlantic Oscillation (NAO) on early autumn (September) rainfall over Central China (RCC). The results show that a significant positive correlation exists between the preceding summer NAO and the early autumn RCC on the interannual timescale. In order to understand the physical mechanism between them, the role of ocean was investigated. It was found that the strong summer NAO can induce a tripole sea surface temperature anomaly (SSTA) in the North Atlantic; this SSTA pattern can persist until early autumn. The diagnostic analysis showed that the tripole SSTA pattern excites a downstream Atlantic-Eurasian (AEA) teleconnection, which contributes to an increase in RCC. The circulation anomalies related to SSTA caused by the weak NAO are opposite, so the RCC is less than normal. The results imply that the preceding summer NAO may be regarded as a forecast factor for the early autumn RCC.

AbstractThe ice water content (IWC) distribution in a mixed-phase cloud system was investigated using CloudSat data, aircraft measurements, and the Weather Research and Forecasting (WRF) model. Simulated precipitation and IWC were in general agreement with rain gauge, satellite, and aircraft observations. The cloud case was characterized by a predominant cold layer and high IWC throughout the cloud-development and precipitation stages. The CloudSat-retrieved products suggested that the IWC was distributed from 4.0 to 8.0 km, with the maximum values (up to 0.5 g m-3) at 5.0-6.0 km at the earlymature stage of cloud development. High IWC (up to 0.8 g m-3) was also detected by airborne probes at 4.2 and 3.6 km at the late-mature stage. The WRF model simulation revealed that the predominant riming facilitated rapid accumulation of high IWC at 3.0-6.0 km.

This article chose 12 typical dress fabrics to study the properties. FAST testing and Fabric dynamic drape style instrument were used to test 14 fabric characteristics which were predigested through Factor Analysis to extract the main properties, so that the time to test fabric properties need could be saved, and could give a basis for selecting characteristic indices of fabric properties on virtual garment reasonably as well.

In order to improve the fitting of garment on shoulder, the measurement of 275 young females aged from 20-24 were taken with 3D-body scanner; the position data relating to the shoulder was conducted using cluster analysis, and extracted 5 characteristic indices that contained almost information of shoulder shape; the rationality of clustering shoulder shape to 4 different types was tested and verified through using one-way analysis of variance; then established the Fisher Discriminant Analysis (FDA) model to identify the young females’ shoulder shape. The result showed that the forecasting model of Fisher Discriminant Analysis (FDA) had excellent performance, high prediction accuracy, so it provided a new method to identify young females’ shoulder shape.

Using Martin Meter from Japan to measure 110 young women body. Using SPSS software for correlation analysis of measurement data, then selecting width, thickness and weight as elements used for establishing leg girth regression models. Adopting backward regression method to choose variable further, and establishing Multiple Linear regression model, Multivariate Quadratic regression model, Multivariate Cubic regression model to predict the girth of each part of leg which related to clothing. After testing and comparing the effect of each model, choosing out the best fitting modle for each part. The validity of modles were tested by randomly selecting 20 young women’s leg data,comparing with manual measurements, gaining satisfactory results. So as to provide an important technical support for human leg two-dimensional non-contact measurement and be further applied to research on medical compression stockings.

A serious disease occurred in many Haliotis diversicolar Reeve farms during 1999 and 2002. The symptoms of the infected abalone were as follows: the pleopod became stiff, its surface became black, and the mantle shrank. All sizes of abalone became infected and mortality was high. A spherical virus was detected in the tissues of the digestive gland. mantle, gill, and intestine of infected animals. It was observed in the cytoplasm and had a diameter about 100-130 nm. Electron microscope examination showed that organelles of infected cells, such as the endoplasmic reticulum; expanded, mitochondria dilated. nuclear membranes dissolved or disappeared, and the edges of the nucleolus swelled. The pathogenicity of the virus was confirmed by experimental infection. [ABSTRACT FROM AUTHOR]

Energy efficiency is very important for wireless sensor networks (WSNs) since sensor nodes have a limited energy supply from a battery. So far, a lot research has focused on this issue, while less emphasis has been placed on the adaptive sleep time for each node with a consideration for the application constraints. In this paper, we propose a hierarchically coordinated power management (HCPM) approach, which both addresses the energy conservation problem and reduces the packet forwarding delay for target tracking WSNs based on a virtual-grid-based network structure. We extend the network lifetime by adopting an adaptive sleep scheduling scheme that combines the local power management (PM) and the adaptive coordinate PM strategies to schedule the activities of the sensor nodes at the surveillance stage. Furthermore, we propose a hierarchical structure for the tracking stage. Experimental results show that the proposed approach has a greater capability of extending the network lifetime while maintaining a short transmission delay when compared with the protocol which does not consider the application constraints in target tracking sensor networks.