Special Issue: Synthesis and Characterization of Graphene-Based Hybrid Nanostructures

Graphene has numerous outstanding physical properties such as excellent electron mobility, extremely high thermal conductivity, high flexibility, remarkable mechanical strength, and high transparency [...]

A Research on Traceability Technology of Agricultural Products Supply Chain Based on Blockchain and IPFS

Blockchain technology, the fundamental technology of Bitcoin, is featured with high transparency, decentralization, traceability, tamperproof nature, and anonymousness. In this thesis, a case study of the traceability of agricultural products is to explain a traceability solution of agricultural products supply chain based on blockchain and IPFS. The latter one is used to store large quantities of transactions data; and the former one is used for the safety of data storage and circulation. And consumers can know the quality of agricultural products in the shortest time through the evaluation function. As shown in the experiment, the solution is more efficient and secure compared with existing supply chain traceability methods, meeting the traceability requirements of security, transparency, and reliability. Furthermore, the traceability, safety, and performance of the scheme are also analyzed here.

Transparent and Flexible Vibration Sensor Based on a Wheel-Shaped Hybrid Thin Membrane

With the advent of human–machine interaction and the Internet of Things, wearable and flexible vibration sensors have been developed to detect human voices and surrounding vibrations transmitted to humans. However, previous wearable vibration sensors have limitations in the sensing performance, such as frequency response, linearity of sensitivity, and esthetics. In this study, a transparent and flexible vibration sensor was developed by incorporating organic/inorganic hybrid materials into ultrathin membranes. The sensor exhibited a linear and high sensitivity (20 mV/g) and a flat frequency response (80–3000 Hz), which are attributed to the wheel-shaped capacitive diaphragm structure fabricated by exploiting the high processability and low stiffness of the organic material SU-8 and the high conductivity of the inorganic material ITO. The sensor also has sufficient esthetics as a wearable device because of the high transparency of SU-8 and ITO. In addition, the temperature of the post-annealing process after ITO sputtering was optimized for the high transparency and conductivity. The fabricated sensor showed significant potential for use in transparent healthcare devices to monitor the vibrations transmitted from hand-held vibration tools and in a skin-attachable vocal sensor.