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In this study, a simple, robust and effective electrochemical sensor was constructed for ultrasensitive and selective detection of organophosphorus (OPs). DCNP (diethylcyanophosphonate, a nerve agent mimic) was selected as a representative OP to investigate the analytical performance of the presented sensor. 3 dimession graphene-gold nanoparticles (3DGH-AuNPs) composites were simply synthesized via one-pot hydrothermal reaction and characterized using TEM and XRD. Preparation of 4-aminoacetophenone oxime (APO) was performed via oximation reaction of 4-aminoacetophenone using hydroxylamine hydrochloride and characterized by FT-IR. And analytical performance of GCE/3DGH-AuNPs/APO based sensor for DCNP discrimination was carried out under optimized detection condition. A decent linear relationship for DCNP was obtained in the range from 1 × 10 −11 to 7 × 10 −8 M, with low detection limit of 3.45 × 10 −12 M. Additionally, the presented sensor displayed decent selectivity towards not only DCNP, but also other OPs, such as diphenyl chlorophosphate (DCPP), dimethoate, fenitrothion etc. And reproducibility and stability of the sensor were also evaluated. These results demonstrated that the presented electrochemical sensor can be a promising sensing platform for OPs analysis.

In this paper, in order to understand the fiber Bragg grating (FBG) sensor's temperature sensing properties with different coating materials and packaging materials at low temperature, and choose a FBG sensor for engineering application, an experimental platform is designed at first, the temperature sensing performance of five different type of FBG sensors at low temperature (77K–296K) is studied, and then the wavelength-temperature curve and temperature sensitive coefficient curve of these five FBG sensors is analyzed. At last, a nonlinear fitting for the best wavelength-temperature curve is made to provide a reference for practical application. It is concluded that polyimide-coated FBG sensor can be used normally at low temperature, and the temperature sensitive coefficient increases 4.32pm/K as reference to bare FBG, packaging has few effect on the sensor's performance of grating sensors. The OS4200 whose wavelength-temperature curve's cubic curve fitting is better than quadratic curve fitting has high accuracy and good stability, it can meet the requirement in practical engineering.