5 results about "Desorption time" patented technology

The invention relates to the technical field of tobacco leaf element analysis, in particular to a detection method for volatile compounds in tobacco leaves and a clustering analysis method for the tobacco leaves. The method for detecting the volatile compounds in the tobacco leaves comprises the following steps: drying and pulverizing tobacco leaves to be detected to prepare sample powder of the tobacco leaves to be detected; extracting the mixed solution of the tobacco leaf sample powder to be detected and the internal standard solution by adopting a headspace solid-phase microextraction method to prepare an extracting solution; carrying out gas chromatography-mass spectrometry detection on the extract liquor; wherein an extraction head used by the headspace solid-phase microextraction method is a divinylbenzene / carbon molecular sieve / polydimethylsiloxane composite coating extraction head, and the parameters of the headspace solid-phase microextraction method are as follows: the extraction temperature is 75-85 DEG C, the extraction time is 45-55 minutes, the desorption time is 4-6 minutes, and the equilibrium time is 3-7 minutes. The method for detecting the volatile compounds in the tobacco leaves, provided by the invention, can effectively separate and analyze the volatile components, and is simple and efficient.

The application discloses a kind of pollution adsorbent particle residual adsorption amount determination method and system, it is related to pollution adsorbent particle desorption research technical field.The application constructs improved Lan* desorption kinetics model;Based on origin software and desorption kinetics experimental data, the coefficient in improved Lan* desorption kinetics model is fitted, and residual adsorption amount prediction model of pollution adsorbent particle is obtained;Target desorption time is substituted into residual adsorption amount prediction model of pollution adsorbent particle, and the residual adsorption amount of unit mass pollution adsorbent particle at target desorption time is determined.The application can quickly complete the prediction of the residual adsorption amount of adsorbate of unit mass adsorbent at any desorption time by introducing solid-liquid ratio to construct improved Lan* desorption kinetics model.

The present application relates to the technical field of persistent organic pollutants enrichment detection, and discloses a polycyclic aromatic hydrocarbon gas chromatography detection technology method based on hydrophobic covalent organic framework solid-phase microextraction fiber.The solid-phase microextraction fiber comprises a metal fiber as a core, is wrapped with polydopamine, and is obtained by growing a trifluoromethyl covalent organic framework in situ layer by layer; when 16 kinds of polycyclic aromatic hydrocarbons are enriched, the extraction time is as low as 12-19 min, and the desorption time is as low as 3-5 min.The solid-phase microextraction fiber cooperates with headspace sampling-gas chromatography-mass spectrometry to achieve a polycyclic aromatic hydrocarbon detection limit as low as 0.16 ng mL ‑1 The following has the advantages of precision RSD < 5.98%, wide detection range, and high polycyclic aromatic hydrocarbon substance detection rate.

A method and apparatus for identifying a difficult-to-differentiate bacterial species, a device, and a medium, relating to the technical field of microbial identification, and comprising: acquiring a mass spectrometry identification result sent by a source mass spectrometer, determining whether a difficult-to-differentiate bacterial species is present in the mass spectrometry identification result, and if the difficult-to-differentiate bacterial species is present in the mass spectrometry identification result, determining whether there is a fine-grained differential analysis model corresponding to a type of the difficult-to-differentiate bacterial species in a model library; if there is a fine-grained differential analysis model corresponding to the type of the difficult-to-differentiate bacterial species in the model library, invoking the fine-grained differential analysis model to analyze and identify the difficult-to-differentiate bacterial species so as to obtain a model analysis and identification result; if there is no fine-grained differential analysis model corresponding to the type of the difficult-to-differentiate bacterial species in the model library, using a dynamic matching algorithm to perform dynamic computational identification on the difficult-to-differentiate bacterial species, or using the dynamic matching algorithm and invoking the fine-grained differential analysis model to perform dynamic computational identification on the difficult-to-differentiate bacterial species to obtain a dynamic computational identification result, thereby improving matrix-assisted laser desorption time-of-flight mass spectrometer accuracy and efficiency with respect to identifying similar microorganisms.

The invention relates to the technical field of cigarette detection, in particular to a method and a device for detecting the barrier property of a cigarette packaging material to tobacco shred aroma components. The detection method comprises the following steps: capturing by using a Carbotrap 349 adsorbent; the captured Carbotrap 349 adsorbent is subjected to thermal desorption, and the thermal desorption conditions are as follows: the carrier gas is helium, and the flow rate is 35-45 mL / min; the first-stage desorption temperature is 310 to 330 DEG C; the first-stage desorption time is 8 to 12 minutes; the adsorption temperature of the cold trap is-35 to-45 DEG C; the second-stage desorption temperature is 290 to 310 DEG C; the second-stage desorption time is 8 to 12 minutes; the valve temperature is 240-260 DEG C; the temperature of the transmission line is 240-260 DEG C; the split ratio is 1: (8-12); and carrying out gas chromatography-mass spectrometry detection on the volatile small molecule components obtained by thermal desorption. By adjusting the selection of the adsorbent and the corresponding thermal desorption condition, the interference caused by the migration component of the cigarette packaging material is avoided, and the accuracy of the detection result is improved.