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The rapid detection of organophosphorus pesticide residues in food is crucial to food safety. One type of novel, magnetic, molecularly-imprinted polymeric microsphere (MMIP) was prepared with vinyl phosphate and 1-octadecene as a collection of dual functional monomers, which were screened by Gaussian09W molecular simulation. MMIPs were used to enrich organic phosphorus, which then detected by fluorescence quenching in vinyl phosphate-modified carbon dots (CDs@VPA) originated from anhydrous citric acid. MMIPs and CDs@VPA were characterized by TEM, particle size analysis, FT-IR, VSM, XPS, adsorption experiments, and fluorescence spectrophotometry in turn. Through the fitting data from experiment and Gaussian quantum chemical calculations, the molecular recognition properties and the mechanism of fluorescence detection between organophosphorus pesticides and CDs@VPA were also investigated. The results indicated that the MMIPs could specifically recognize and enrich triazophos with the saturated adsorption capacity 0.226 mmol g−1, the imprinting factor 4.59, and the limit of recognition as low as 0.0006 mmol L−1. Under optimal conditions, the CDs@VPA sensor has shown an extensive fluorescence property with a LOD of 0.0015 mmol L−1 and the linear range from 0.0035 mmol L−1 to 0.20 mmol L−1 (R2 = 0.9988) at 390 nm. The mechanism of fluorescence detection of organic phosphorus with CDs@VPA sensor might be attributable to hydrogen bonds formed between heteroatom O, N, S, or P, and the O−H group, which led to fluorescent quenching. Meanwhile, HN−C=O and Si−O groups in CDs@VPA system might contribute to cause excellent blue photoluminescence. The fluorescence sensor was thorough successfully employed to the detection of triazophos in cucumber samples, illustrating its tremendous value towards food sample analysis in complex matrix.

The overuse of cartap in tea tree leads to hazardous residues threatening human health. A colorimetric determination was established to detect cartap residues in tea beverages by silver nanoparticles (AgNP) sensor with magnetic molecularly imprinted polymeric microspheres (Fe3O4@mSiO2@MIPs) as recognition elements. Using Fe3O4 as supporting core, mesoporous SiO2 as intermediate shell, methylacrylic acid as functional monomer, and cartap as template, Fe3O4@mSiO2@MIPs were prepared to selectively and magnetically separate cartap from tea solution before colorimetric determination by AgNP sensors. The core-shell Fe3O4@mSiO2@MIPs were also characterized by FT-IR, TEM, VSM, and experimental adsorption. The Fe3O4@mSiO2@MIPs could be rapidly separated by an external magnet in 10 s with good reusability (maintained 95.2% through 10 cycles). The adsorption process of cartap on Fe3O4@mSiO2@MIPs conformed to Langmuir adsorption isotherm with maximum adsorption capacity at 0.257 mmol/g and short equilibrium time of 30 min at 298 K. The AgNP colorimetric method semi-quantified cartap ≥5 mg/L by naked eye and quantified cartap 0.1–5 mg/L with LOD 0.01 mg/L by UV-vis spectroscopy. The AgNP colorimetric detection after pretreatment with Fe3O4@mSiO2@MIPs could be successfully utilized to recognize and detect cartap residues in tea beverages.

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In this paper, a novel fuzzy Proportion Integration Differentiation (PID) controller is proposed to extract the optimal energy from wind for a hydraulic offshore wind turbine. Firstly, in order to calculate the theoretical power, an adaptive neuro‐fuzzy inference system (ANFIS) is designed for wind speed evaluation, in which the input parameters include rotor speed, rotor torque, and pitch angle, and the output parameter is the estimated wind speed. Then, the optimal power coefficient is achieved by controlling the hydraulic pump torque to tracking the optimal rotor speed, and a fuzzy PID is designed to adjust the pump displacement and to obtain the optimal hydraulic pump torque. Furthermore, aiming to meet the various output power demand, a hydraulic accumulator is utilized for storing the excess energy, and a PID controller is designed for distributing the hydraulic energy between the accumulator and the Pelton turbine. Finally, the performance of proposed controls system are confirmed by two case simulations on a 5 MW hydraulic offshore wind turbine. The simulation results show that, compared with the conventional control methods (fuzzy logical and PID controller) used in electro‐hydraulic servo system, the fuzzy PID controller can provide the better tracking effect with a faster speed and a minimal steady‐state oscillation. Moreover, with the use of a hydraulic accumulator, all the power fluctuations from the wind speed disturbances are damped out and the output power become controllable.

Using Cu 2+ as template ion, three sodium alginate hydrogel beads including SA, SAC, and SAB beads were prepared with sodium alginate blending with different precursors of carboxymethyl cellulose and βcyclodextrin, respectively. The effect of pH, adsorption time, initial concentration of Cu 2+ , adsorbent dosage, and coexisting ions on the adsorption e ciency of three hydrogel beads was investigated. The results indicated that adding carboxymethyl cellulose and β-cyclodextrin into skeleton of beads increased the toughness of the beads and improved the adsorption capacity of Cu 2+ . The adsorption rate of Cu 2+ on SA beads was conformed to the pseudo-rst order kinetic equation, while the adsorption behavior of Cu 2+ on SAC or SAB beads could be con rmed to the pseudo-second-order kinetic equation. Compared with the saturated adsorption capacity 510 mg/g of Cu 2+ on SA, the saturated adsorption capacity of Cu 2+ on SAB and SAC reached 817 mg/g and 822 mg/g, respectively, with their Cu 2+ adsorption e ciency over 95% at 25°C. Thus, SAC and SAB beads could be used as adsorption material for detecting and removing Cu 2+ from wastewater.