Electromagnetic wave (EMW)-absorbing materials have a great impact on civil use and national defense. In this paper, a novel composite, RGO@6CoTe2-300 (the mass ratio of reduced graphene oxide to CoTe2 is 1:6, annealed at 300 °C), has been obtained through a facile melt-diffusion method and solvothermal method. The as-prepared samples have shown excellent reflection losses (RL) and effective adsorption bandwidth (EAB) by controlling the loading of CoTe2 and the annealing temperature. The sample has exhibited a RL of −62.2 dB at 13.04 GHz with the matching thickness of 3.53 mm, and the EAB reaches 8.2 GHz at 2–18 GHz. Moreover, excellent terahertz (THz) absorption property is also obtained at 0.2–2.0 THz. A RL of 54.07 dB is acquired, and the EAB covers 100% of the entire measured bandwidth. Thus, RGO@6CoTe2-300 can be considered as a promising EMW absorption material in both gigahertz and terahertz band ranges.
Diffusion limitations and nonspecific surface absorption are great challenges for developing micro-/nanoscale affinity biosensors. There are very limited approaches that can solve these issues at the same time. Here, an acoustic streaming approach enabled by a gigahertz (GHz) resonator is presented to promote mass transfer of analytes through the jet mode and biofouling removal through the shear mode, which can be switched by tuning the deviation angle, α, between the resonator and the sensor. Simulations show that the jet mode (α ≤ 0) drives the analytes in the fluid toward the sensing surface, overcomes the diffusion limitation, and enhances the binding; while the shear mode (0 < α < π/4) provides a scouring action to remove the biofouling from the sensor. Experimental studies were performed by integrating this GHz resonator with optoelectronic sensing systems, where a 34-fold enhancement for the initial binding rate was obtained. Featuring high efficiency, controllability, and versatility, we believe that this GHz acoustic streaming approach holds promise for many kinds of biosensing systems as well as lab-on-chip systems.
Hydrodynamic force loading platforms for controllable cell mechanical deformation play an essential role in modern cell technologies. Current systems require assistance from specific microstructures thus limiting the controllability and flexibility in cell shape modulation, and studies on real-time 3D cell morphology analysis are still absent. This article presents a novel platform based on acoustic streaming generated from a gigahertz device for cell shape control and real-time cell deformation analysis. Details in cell deformation and the restoration process are thoroughly studied on the platform, and cell behavior control at the microscale is successfully achieved by tuning the treating time, intensity, and wave form of the streaming. The application of this platform in cell membrane permeability modulation and analysis is also exploited. Based on the membrane reorganization during cell deformation, the effects of deformation extent and deformation patterns on membrane permeability to micro- and macromolecules are revealed. This technology has shown its unique superiorities in cell mechanical manipulation such as high flexibility, high accuracy, and pure fluid force operation, indicating its promising prospect as a reliable tool for cell property study and drug therapy development.
危险品化学品经营许可证（带存储）