Objective To investigate the agglomeration of particulate matter at the air-leaf interface and provide guidance for the prevention and control of particulate matter and greening planning. Methods In this study, the effects of temperature and wind speed on plant coagulation effect were studied by using a self-developed system of coagulation effect based on aerosol smoke box, and the coagulation effect of particulate matter in the leaves of 10 common green tree species in Shanghai was measured. Results The coagulation effect of plant leaves is affected by external conditions, which increases and then decreases with the increase of temperature and is positively correlated with wind speed; among different plants, the coagulation effect of coniferous species is greater than that of broad-leaved species, small-leaved species is greater than that of large-leaved species. Conclusion The results of the study can provide scientific basis for the key prevention and control management of haze, the plant configuration mode of green space community and the selection of urban greening tree species.

Objective Based on UHPLC-Orbitrap HRMS, combined withQuECHERS pretreatment technology, a rapid screening detection method wasestablished to simultaneously screen and confirm 14 categories of 140illegally added drugs in herbal tea. Methods The sample was extractedwith methanol, and purified by dispersed solid phase extraction withsodium acetate and anhydrous magnesium sulfate, neutral alumina andoctadecyl bonded silica gel, separated by a chromatographic columnWaters BEH ${\mathrm{C}}_{18}\left({{2.1}\mathrm{\;{mm}}\times {50}\mathrm{\;{mm}},{1.7\mu}\mathrm{m}}\right)$ , and gradient eluted by two independentmobile phase systems: ${0.2}\%$ formicacid water $\left({V/V}\right)$ solution $\sim {0.2}\%$ formic acidacetonitrile $\left({V/V}\right)$ solution and water-acetonitrile, Full $\mathrm{{MS}}/{\mathrm{{dd}- {MS}}}^{2}$ mode was used to collect data, the standard curve was prepared byextracting solution from blank sample and the external standard methodwas used for quantification. Results The linear relationship of 20representative quality control compounds was good $\left({{r}^{2}> {0.995}}\right)$ from5.0 to ${200}\mathrm{{ng}}/\mathrm{{mL}}$ massconcentration, the average recovery rateat the three levels of low,medium and high is between 83.1% and 107.3%, the relative standarddeviation is less than 15.6% and detection low limit is between ${0.2}\mathrm{{mg}}/\mathrm{{kg}}$ and ${1.0}\mathrm{{mg}}/\mathrm{{kg}}$ .165 herbal tea samples on the market were determined and results showedthat twelve samples were positive, the positive components werechlorpheniramine, acetaminophen, diclofenac sodium, ibuprofen,dexamethasone acetate, erythromycin and florfenicol. Conclusion Themethod has the advantages of simple operation, high sensitivity andhigh-throughput screening. Is suitable for the detection of illegallyadded drugs in herbal tea and other health foods.

Objective To compare the different extraction methods of soybean crude fatty acid value with the national standard method GB 5009.229-2016 National Standard forFood Safety-Determination of Acid Value in Food. Methods The room temperature extraction method, organic solvent oscillation method, and ultrasonic assisted method were used to detect the crude fatty acid value of soybeans, and compared with the Soxhlet extraction method required by the national standard method. Results The crude fatty acid value of soybeans measured by 3 kinds of extraction methods is basically consistent with the national standard method, and the extraction speed is significantly faster than the Soxhlet extraction method in the national standard. Among them, the ultrasonic assisted extraction method has the shortest extraction time, only requiring 20 minutes; as the sample size increases, the extraction efficiency of the room temperature extraction method improves more significantly. Conclusion Daily testing of grain and oil enterprises can shorten time, reduce costs, and improve efficiency by selecting suitable extraction methods based on sample batch size.

Objective To determine the content of phosphoric ester flame retardants in samples and provide a scientific basis for optimizing the flame retardancy of plastic products. Methods The phosphoric ester flame retardants were extracted from plastic samples with suitable solvent, and the content of phosphoric ester flame retardants was determined by GC-MS. Results The method is fine and can effectively remove impurity interference, can effectively remove the interference of impurities, has a good linearity with a correlation coefficient of more than 0.995; has a good precision with a relative standard deviation of less than 10%; a spiked recovery test was carried out throughout the process, and the recovery rate was 80%~120%. Conclusion This method is accurate and reliable, and can be used for the determination of the content of phosphate ester flame retardants in samples.

Objective Evaluation of ochratoxin A (OTA) contamination inGejie Dingchuan Pills. Methods Eighty-six samples from sevenpharmaceutical manufacturers were analyzed for OTA content usingultra-high-performance liquid chromatography-tandem mass spectrometry.Results The method displayed excellent linearity within the range ofconcentrations ${0.1}\sim {10}\mathrm{{ng}}/\mathrm{{mL}}$ .The limits of detection and quantification were ${0.2}\mathrm{{\mu g}}/\mathrm{{kg}}$ and $1\mathrm{{\mu g}}/\mathrm{{kg}}$ ,respectively. Seventy-two samples were detected to be contaminated withOTA, resulting in an 84% positive rate. Furthermore, ten samples failedto meet the required standards, reflecting a failure rate of 12%. Theactual sample test results showed that the OTA detection rate of GejieDingchuan pills was high and the pollution was serious, which suggestedthe urgency of detecting and determining the maximum OTA limit ofproprietary Chinese medicine. Conclusion This study assesses the extentof OTA contamination in Gejie Dingchuan pills, offering a scientificbasis for future investigations of OTA maximum limits in Chineseproprietary medicines.

Objective To evaluate the uncertainty in the determinationof thiamethoxam content in corn by high-performance liquidchromatography-tandem mass spectrometry. Methods According to GB/T20770-2008 Determination of 486 Pesticides and Related ChemicalsResidues in Grains-Liquid Chromatography-Tandem Mass Spectrometrymethod, by establishing a mathematical model, the sources of uncertaintywere analyzed and the effects of different sources were measured andcalculated. Results Forthe corn samples with a mass fraction of ${0.282}\mathrm{{mg}}/\mathrm{{kg}}$ ofthiamethoxam, the extended uncertainty was ${0.041}\mathrm{{mg}}/\mathrm{{kg}}\left({P={95}\%, k = 2}\right)$ . Conclusion The main source ofuncertainty affecting the test result is the determination of samplesolution.

Under the new circumstances of rapid social and economic development in China, higher education is experiencing significant growth. The government is increasingly emphasizing the importance of laboratory safety in science and engineering universities. Given the significant roles of university laboratories in teaching and research, laboratory safety is characterized by diversification, complexity, and specialization. This paper analyzes the main challenges faced by safety management in engineering university laboratories and proposes improvement measures from four perspectives: strengthening and refining the laboratory safety management responsibility system, timely revision of safety-related documents, promoting safety awareness and education, intensifying laboratory safety inspections, establishing a laboratory safety management information system. These measures aim to enhance the overall level of laboratory safety management, providing solid support for the safe operation of laboratories and facilitating teaching and research activities.

Objective Collect peanuts and soybeans in Beijing throughvarious channels, determine the content of 26 metal elements among them.Methods The sample is pre-processed by using a microwave to eliminatethe sample, the content of 26 metal elements was determined by inductivecoupling plasma body constituent. Results The detection limit and linearrange of 26 elements can meet the detection requirements, thecorrelation coefficients are above 0.9980 or more, relative standarddeviation (RSD) in the range of 1.1% to 6.8%, the average recovery rateis within the range of 88.8% to 108.7%. In general the content of $\mathrm{K}$ , Ca, and $\mathrm{{Fe}}$ in soybeans far exceedspeanuts, Al in ordinary soybeans is significantly higher than organicsoybeans, the $\mathrm{{Fe}}$ of redpeanut peanuts is higher than white peanut peanuts. $\mathrm{{Pb}},\mathrm{{Cd}},\mathrm{{Cr}}$ with national standards of food safety have not exceeded the standard.Conclusion Through this method, it can be effectively used for themeasurement of 26 metal elements in peanuts and soybeans.

Laboratories in colleges and universities are important places for scientific practice, facing a large number of teachers and students, and involving the safety and stability of the campus environment. Aiming at the current situation of gaseous pollutant emission and management in teaching laboratories of colleges and universities at home and abroad, a comprehensive research has been carried out by means of web browsing, literature reading, field examination and questionnaire survey, etc. The research includes: types of gaseous pollutants in laboratories and methods of their disposal, the current situation and problems of gaseous pollutant emission in laboratories of domestic colleges and universities, the advantages of gaseous pollutant management in laboratories of foreign colleges and universities and the results of the analysis based on research Based on the results of the research, the study and the corresponding countermeasures are given, in order to provide reference for the emission and control of gaseous pollutants in teaching laboratories of universities in China.

The article delves into real-time data processing methods for monitoring tool wear in computer numerical control (CNC) machine tools, with the aim of improving the overall accuracy of the tool monitoring system. The article also systematically reviews several mainstream data processing methods, including power spectrum analysis, wavelet transform, artificial neural network technology, and multi-sensor information fusion technology. Although these methods have their own advantages and disadvantages, a single method often fails to achieve ideal results when dealing with data in complex and changing processing environments. To overcome this challenge, this paper proposes a multi-sensor information fusion data processing method based on hybrid intelligent algorithms