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It is crucial that simple and high-throughput methods for determining multiple, or groups of, sulfonamides (SAs) be developed since they are widely used in animal husbandry and aquaculture. We developed a paper-based multicolor colorimetric aptasensor to detect 3 SAs: sulfaquinoxaline (SQ), sulfamethoxypyridazine (SMP) and sulfamethoxydiazine (SMD). Using a broad-specificity aptamer as a bioreceptor, we reduced the growth of nicotinamide adenine dinucleotide I (NADH)–ascorbic acid (AA)-mediated gold nanobipyramids (AuNBPs) to generate a multicolor signal. We also used a paper-based analytical device (PAD) system to deposit AuNBPs for a sensitive color signal read out. The aptasensor can detect more color changes corresponding to the concentrations of SQ, SMP and SMD and has higher sensitivity, better specificity and stability. It can also be used to determine SQ, SMP and SDM individually, or collectively, or any two together with a visual detection limit of 0.3–1.0 µM, a spectrometry quantification limit (LOQ) of 0.3–0.5 µM and a spectrometry detection limits (LOD) of 0.09–0.15 µM. The aptasensor was successfully used to determine SQ, SMP and SDM in fish muscle with a recovery of 89–94% and a RSD n = 5) < 8%, making it a promising method for the rapid screening of total SQ, SMP and SDM residue in seafood. [ABSTRACT FROM AUTHOR]

In this paper, a three‐dimensional simulation model of the engine cylinder is established using commercial simulation software AVL‐Fire, and the accuracy of the model is verified with experimental results. The effects of diesel/biodiesel/n‐butanol blends on diesel engine performance, and combustion and emissions characteristics were investigated by performing simulation operations on the model. The combustion process in the cylinder was simulated for 0%, 5%, 10%, 15%, and 20% of n‐butanol in the fuel mixture. The results showed that at 75% load, the brake thermal efficiency of D95N5, D90N10, D85N15, and D80N20 engines increased by 0.84%, 1.68%, 2.48%, and 3.19%, respectively, and soot emissions decreased by 2.76%, 5.52%, 8.25%, and 10.96%, respectively, compared with D100. However, the brake power of the engine was reduced, the brake ratio fuel consumption increased, and NOx emission increased. In addition, at all loads, soot and CO emissions decrease as the percentage of n‐butanol in the fuel mixture increases. [ABSTRACT FROM AUTHOR]