The Internet of Things (IoT)1,2 employs a large number of spatially distributed wireless sensors to monitor physical environments, e.g., temperature, humidity, and air pressure, and has many applications, including environmental monitoring3, health care monitoring4, smart cities5, and precision agriculture. A wireless sensor can collect, analyze, and transmit measurements of its environment1,2. Currently, wireless sensors used in the IoT are predominately based on electronic devices that may suffer from electromagnetic interference in many circumstances. Being immune to the electromagnetic interference, optical sensors provide a significant advantage in harsh environments6. Furthermore, by introducing optical resonance to enhance light–matter interactions, optical sensors based on resonators exhibit small footprints, extreme sensitivity, and versatile functionalities7,8, which can significantly enhance the capability and flexibility of wireless sensors. Here we provide the first demonstration of a wireless photonic sensor node based on a whispering-gallery-mode (WGM) optical resonator, in which light propagates along the circular rim of such a structure like a sphere, a disk, or a toroid by continuous total internal reflection. The sensor node is controlled via a customized iOS app. Its performance was studied in two practical scenarios: (1) real-time measurement of the air temperature over 12 h and (2) aerial mapping of the temperature distribution using a sensor node mounted on an unmanned drone. Our work demonstrates the capability of WGM optical sensors in practical applications and may pave the way for the large-scale deployment of WGM sensors in the IoT.

In the present study, we design a novel hot stamping steel containing high amounts of C and Si and micro-alloying element (i.e. Nb). The steel was subjected to quenching and partitioning (Q&P) process. The new Q&P treated hot stamping steel exhibits a significantly improved mechanical property in terms of strength, ductility and impact toughness compared with the traditional 22MnB5 hot stamping steel. The influence of partitioning time on the microstructure and mechanical properties was investigated. The retained austenite (RA) fraction and the carbon content of RA significantly increased with higher partitioning times. With increasing partitioning time, the uniform elongation, total elongation, strength-ductility balance and impact energy was also remarkably enhanced. The maximum strength-ductility balance achieves around 23 GPa %.

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Intractable cancer has threatened human health all the time. Emerging sonodynamic and photothermal therapy based on biocompatible black phosphorus (BP) nanomaterials have become an attractive strategy due to the satisfactory synergistic effect, low side effect, and good biocompatibility. However, sonodynamic therapy of pure black phosphorus nanosheets (BPS) is limited for fast electron recombination owing to its special band gap. To solve this challenge, the modified nanocomposites (NCs) integrating gold nanoparticles and polypyrrole (PPy) with BPS were harvested through a moderate approach. The nanocomposites showed the superior in vitro sonodynamic and photothermal conversion effect through tumor cells. Moreover, compared with most of the reported two-dimensional nanomaterials, it was demonstrated that Au-BPS-PPy-PEG nanocomposites (i.e., GBP-PEG NCs) have the advantages of the synergistic therapeutic effect and ignorable side effect through the 4T1-bearing tumor model and biocompatible evaluation, respectively, attributing to the enhanced electron transfer capacity, good biocompatibility of BPS, and prominent photothermal conversion capacity of PPy. The above results indicate that the prepared NCs have good application prospects in the field of biomaterials for cancer therapy.