Binwang Yang,Xiuqing Zheng,Feiyu Lu,Jianna Yu,Guoxing Jing,Wen Liu,Wenshan Li,Zhaohong Wang,Wenjie Liu
Black powder (BP), a low-explosive mixture, is created by mixing sulfur, potassium nitrate, and charcoal, poses significant risks due to its flammability and potential use in illicit activities. Accurate detection of black powder (BP) is crucial for public safety, security, and regulatory compliance. However, the detection of BP is challenging when using miniaturized ion mobility spectrometers because of the sulfur ion peak overlaps heavily with that of the reactant ions ( O 2 − ( H 2 O ) n ). A simple method is proposed in this study for accurate and sensitive detection of BP, utilizing a miniaturized Fourier deconvolution ion mobility spectrometer (FD-IMS), which directly improves the resolution between the O 2 − ( H 2 O ) n peak and the sulfur ion peak without the need to add any chlorinated hydrocarbon modifiers, and avoids the complexities and contamination risks posed by modifiers in the conventional method. The demonstrated device achieved a resolution of up to 2.07 between the O 2 − ( H 2 O ) n and S 3 − ion peaks at a drift region voltage and length of 1.54 kV and 42.5 mm, under optimized detection temperature and drift gas humidity, with a minimum detectable quality of sulfur of less than 0.1 ng. It was proven that this miniaturized FD-IMS is qualified to detect trace level BP less than 1 ng as well as other nitro-organic explosives.
The objective of this study was to investigate the umami characteristics of soy sauce using electronic tongue evaluation and amino acid composition and matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI−TOF MS) analysis. The soy sauce peptides were isolated from soy sauce using XAD−16 macroporous resin combined with ethanol solution. The results showed that the soy sauce peptide fraction eluted by 60% ethanol (SS−60%) exhibited a prominent umami taste, and the umami scores were highly positively correlated with the amino acid nitrogen contents of soy sauces. The umami scores of SS−60% were significantly positively correlated with the contents of free amino acids. Especially, Phe showed the highest positive correlation with the umami scores. In addition, five characteristic ion peaks withm/zat 499, 561, 643, 649, and 855 were identified in the peptide mass fingerprinting. Therefore, this study provides new insights into the umami characteristics for the taste evaluation and reality identification of soy sauce.
危险品化学品经营许可证（带存储）