As an inevitable product in coal mine production, dust has a wide range of sources. These dust not only have complex physical and chemical properties, but their concentration and distribution characteristics are also affected by various factors. This article aims to comprehensively and systematically study the characteristics and hazards of coal mine underground dust through fixed-point sampling and detection analysis methods. By selecting and arranging sampling points, preparing and calibrating sampling instruments, and performing specific operations during the sampling process, the accuracy of data is ensured. At the same time, based on the detection results, the concentration, particle size distribution, chemical composition, and explosiveness of dust are revealed, in order to provide effective basis for the development of targeted dust prevention measures.

Objective To investigate and analyze the microbial contamination in the production and processing of pre-packaged sauced meat products in Sichuan Province. Methods The total number of bacterial colonies, coliform, Staphylococcus aureus, Listeria monocytogenes, Salmonella and Bacillus cereus were detected in 52 samples from a pre-packaged spiced meat factory in Sichuan province by national standard method. Results The results showed that the meat products were contaminated by Escherichia coli, Staphylococcus aureus, Bacillus cereus and Listeria monocytogenes during the curing process. The detection rate of microorganisms gradually decreased with the process of processing, and high temperature sterilization had a significant effect on reducing the microbial pollution of the final product; By tracing analysis, it was found that the environment and equipment in the raw and cooked area were contaminated by Listeria monocytogenes of the same serotype. Conclusion The factory has a big problem of staff hygiene, raw food area and cooked food area cross-contamination, it is recommended that enterprises strictly control the production environment and personnel hygiene, regular cleaning and disinfection, reduce the pollution of processing environment and equipment, workshop operators and food cross-contamination and raw and cooked food cross-contamination, in order to reduce the risk of product microbial contamination.

Objective To analyze the quality control results of detecting influenza virus nucleic acid by fluorescence real-time quantitative PCR. Methods From May 2021 to November 2022, 120 samples of influenza virus infection were studied. The RNA of influenza virus in these samples was extracted by nucleic acid and detected by PCR real-time fluorescence quantitative technique to evaluate its effect. Results 44 cases of influenza B virus, 40 cases of influenza A 1 virus and 36 cases of influenza A 3 virus were detected by this technique. All the test results meet the quality control standards of molecular biology operation, and the qualified rate reaches 100.0%. Conclusion Real-time nucleic acid PCR technology is widely used in clinical influenza virus detection. PCR real-time fluorescence quantitative detection method is accurate and rapid in the detection of influenza virus nucleic acid, which is suitable as the first choice to deal with public health emergencies.

Objective To understand the sanitary condition of secondarywater supply in jinan railway area and provide scientific basis forrailway departments to improve secondary water supply. Methods Accordingto ( Standard test method for drinking water $\}$ , we sampled and tested the waterquality. On the basis of $《$ Hygienic specification for facilities of secondary water supply》, weanalyzed the data about engineering acceptance and daily detection waterquality. Results Daily detection of secondary water supply qualifiedrate was ${82.69}\%$ , higher thanengineering acceptance of secondary water supply qualified rate ${65.77}\%\left({P <{0.05}}\right)$ .Acoording to the daily detection qualified rate analysis of secondarywater supply, the qualified rate of water supply from living area,passenger station, well of the train track and train water tank wasdecreased successively. The difference of the qualification rate amongthe sampling locations is statistically significant $\left({P <{0.05}}\right)$ ; Thequalified rate in each month is all above ${74}\%$ . The qualified rate in March,April, June and September is below 80%.Soil microbial indicators anddisinfectant indicators qualified rate trend consistent with allindicators qualified rate trend. The qualified rate of ex-factory waterwas ${90.54}\%$ , which was higherthan ${81.19}\%$ of peripheral water $\left({P <{0.05}}\right)$ . Theunqualified soil microbial indicators and disinfectant indicators arethe main factors causing the unqualified secondary water supply. Conclusion The qualified rate of secondary water supply in jinan railwayarea is higher than other water supply types, but there are hiddendangers in the health situation. The supervision of secondary watersupply should have further strengthen.

Water is a necessary substance for all living things on the earth, so it is very important to monitor pollutants in the water environment. At present, many analytical methods have been proposed for the detection of water pollutants. Portable sensor detector is of special importance because of its simple operation, low cost and portability. This paper first introduces the application of portable rapid detection technology, and further reviews the research progress of rapid detection technology for biological and non-biological pollutants in water bodies. Finally, the current research progress is summarized, which provides a reference for the further development of rapid detection technology.

As the core component of the current power system of automobiles, the durability of key components has a decisive impact on the overall performance and safety of the vehicle. The purpose of this article is to explore an efficient method for evaluating the durability of core components of automotive engines, in order to improve the reliability of components and the safety of the entire vehicle. The article examines the current development trend of durability assessment technology and analyzes the limitations of existing technologies. Propose a comprehensive evaluation method that integrates experimental verification and numerical simulation, which can effectively evaluate the durability of components in different working environments. Through experimental verification and data analysis, the accuracy and efficiency of the proposed method were verified, and future research directions and improvement suggestions were predicted and anticipated.

The treatment and detection of nickel-containing electroplating wastewater is an important topic in the field of environmental protection. This paper analyzes the generation and composition of nickel-containing wastewater in the electroplating process, and discusses the impact of nickel-containing wastewater on the environment and human health. In order to improve the detection accuracy and efficiency, this paper optimizes the existing detection methods, including the improvement of pre-treatment technology, the optimization of detection equipment and methods, and the application of automated and intelligent detection systems. The experimental study verified the effectiveness of the optimized detection method in improving sensitivity, shortening detection time, and reducing detection costs, providing technical support for the effective management and treatment of electroplating wastewater.

Objective To evaluate the analytical performance of serumamyloid A protein and C-reactive protein detection reagents based onmicrofluidic technology, so as to determine whether they can meetclinical requirements. Methods The precision, accuracy, linear range,interference test and other technical indicators of the detectionreagent were determined according to the CLSI EP scheme. Results Theintra-batch coefficients of variation of high and low concentrationsamples were 0.54% and 1.79%, and the inter-batch coefficients ofvariation were 0% and 1.20%, respectively, for the serum amyloid Adetection reagent; the intra-batch coefficients of variation of high andlow concentration samples were 0.30% and 2.28%, and the inter-batchcoefficients of variation were 0.17% and 0%, respectively, for theC-reactive protein detection reagent; the experimental results of themethodological comparison of the two methods were $\mathrm{Y}=$ -0.0609+0.9871X, ${\mathrm{R}}^{2}= {0.9975}$ and $\mathrm{Y}= {0.3354}+{0.9857}\mathrm{X},{\mathrm{R}}^{2}= {0.9990}$ , respectively,and the allowable errors were greater than the upper limit of theexpected bias confidence interval, and the biases were acceptable; thelinear range of the serum amyloid A detection reagent was $3 \sim {100.0}\mathrm{{mg}}/\mathrm{L}$ ,and the linear range of the C-reactive protein detection reagent was $3\sim {150.0}\mathrm{{mg}}/\mathrm{L}$ . Conclusion The analytical performance of serum amyloid A and C-reactive protein detection reagents based on microfluidic technology can meet the needs of clinical laboratories.

With the continuous development of coal mining, the safe operation of coal mine mechanical and electrical equipment is very important. This paper discusses the application of ultrasonic detection technology in the safety detection of coal mine mechanical and electrical equipment, expounds the principle and characteristics of ultrasonic detection technology, and analyzes its specific application methods in the detection of various faults and defects of coal mine mechanical and electrical equipment, including the detection of mechanical parts and electrical equipment. By discussing the measures of improving the application effect of ultrasonic detection technology, the effectiveness of ultrasonic detection technology in the safety detection of coal mine electromechanical equipment is shown for its reference.

Objective Determination of silicon dioxide in fluorite byalkali fusion-molybdenum blue spectrophotometry. Methods The method ismelted with potassium hydroxide, extracted with water and acidified withsulfuric acid, then, in a weak acidic solution, silicic acid andammonium molybdate form soluble yellow silicomolybdic heteropoly acids,to improve acidity, reduce silicomolybdate yellow to silicomolybdateblue by reducing agent, the absorbance was measured at ${700}\mathrm{\;{nm}}$ and the silicondioxide content was measured. A large number of fluoride interference,the addition of aluminum salt to eliminate. Results Determination ofsilicon dioxide in fluorite by alkali fusion-molybdenum bluespectrophotometry, the silicon dioxide has good calibration curvelinearity, the linear regression equation is $\mathrm{Y}= {0.34733}\mathrm{p}+{0.00228}$ , the correlation coefficient was 0.999; the precisionof the method is less than 1.5%, the accuracy was measured with thenational reference materials, and the relative standard deviation (RSD)was less than 2%. Conclusion It was found that the precision andaccuracy of this method for the determination of silicon dioxide influorite samples were satisfactory and met the requirements of relevantstandards.