Simultaneous oxidation of As(III) and reduction of Cr(VI) by NiS-CdS@biochar through efficient oxalate activation: The key role of enhanced generation of reactive oxygen species.

The reutilization of exhausted biochar is attracting extensive interest among researchers. In this study, the biochar generated from Chinese fir with natural regular porous structure that adsorbed Cd2+/Ni2+ at different concentration levels was used as the precursor, and then combined with simple hydrothermal vulcanization and ion deposition to generate the p-n heterojunction between NiS and CdS compounds (NiS-CdS@C) in situ. The hybrids with 3 cycles of NiS deposition reduced the interfacial transmission resistance from 80 Ω to 40 Ω, and increased photocurrent density by 5 times, thus effectively promoting the separation of photogenerated electrons and holes. The simultaneous removal of As(III) and Cr(VI) was selected to evaluate the oxidation and reduction capacity of the visible light/NiS-CdS@C/oxalate system. The results indicated that 10 mg/L As(III) and Cr(VI) were completely and simultaneously removed with 0.75 mM oxalate addition within 40 min in the system, and the NiS-CdS@C presented good durability and stability for oxalate activation. Electron paramagnetic resonance (EPR) and quenching experiments demonstrated that oxalate was activated by holes under light to produce •CO2- and enhanced the generation of additional •OH and •O2-, further contributing to the oxidation of As(III) and reduction of Cr(VI).

Multifunctional Textile Platform for Fiber Optic Wearable Temperature-Monitoring Application.

Wearable sensing technologies have been developed rapidly in the last decades for physiological and biomechanical signal monitoring. Much attention has been paid to functions of wearable applications, but comfort parameters have been overlooked. This research presents a developed fabric temperature sensor by adopting fiber Bragg grating (FBG) sensors and processing via a textile platform. This FBG-based quasi-distributed sensing system demonstrated a sensitivity of 10.61 ± 0.08 pm/°C with high stability in various temperature environments. No obvious wavelength shift occurred under the curvatures varying from 0 to 50.48 m-1 and in different integration methods with textiles. The temperature distribution monitored by the developed textile sensor in a complex environment with multiple heat sources was deduced using MATLAB to present a real-time dynamic temperature distribution in the wearing environment. This novel fabric temperature sensor shows high sensitivity, stability, and usability with comfort textile properties that are of great potential in wearable applications.

Wearable Fiber Optic Technology Based on Smart Textile: A Review.

Emerging smart textiles have enriched a variety of wearable technologies, including fiber optic technology. Optic fibers are widely applied in communication, sensing, and healthcare, and smart textiles enable fiber optic technology to be worn close to soft and curved human body parts for personalized functions. This review briefly introduces wearable fiber optic applications with various functions, including fashion and esthetics, vital signal monitoring, and disease treatment. The main working principles of side emission, wavelength modulation, and intensity modulation are summarized. In addition, textile fabrication techniques, including weaving and knitting, are discussed and illustrated as combination methods of embedding fiber optic technology into textile fabric. In conclusion, the combination of optical fibers and textiles has drawn considerable interest and developed rapidly. This work provides an overview of textile-based wearable fiber optic technology and discusses potential textile fabrication techniques for further improvement of wearable fiber optic applications.