Ultrasonic flaw detector itself has the characteristics of high detection accuracy, fast detection speed, small size, light weight, and its own ultrasonic non-destructive testing, so it has been widely used in many fields. The measurement accuracy of ultrasonic flaw detector has a non-negligible impact on its function, and it will be affected by various factors in the use process, leading to the deviation of the measurement results. Therefore, it is necessary to do a good job of the measurement verification of ultrasonic flaw detector regularly. The metrological verification of ultrasonic flaw detector is studied and discussed from the Angle of ensuring the performance and measurement accuracy of ultrasonic flaw detector and giving full play to the function of the instrument. In the study, the metrological verification process and precautions of ultrasonic flaw detector are defined, and its dynamic range, horizontal linearity, vertical linearity, sensitivity, false positive rate and resolution are verified. The measurement accuracy of ultrasonic flaw detector has been significantly improved before and after comparative verification, and its own performance can be fully brought into play.

Objective To evaluate the application value ofhigh-performance liquid chromatography fluorescence detection method fordetermining nitrite in drinking water. Method Collect mineral water, tapwater, and source water as water samples, and use high-performanceliquid chromatography fluorescence detection method to determine.Analyze the detection advantages of this method and the stability ofnitrite derivative 2,3 naphthalene triazole in the water standard. Result The nitrite concentration detected in pure water was ${0.6\mu }\mathrm{g}/\mathrm{L}$ , with goodpeak shape and no impurity interference; The detection limit ofhigh-performance liquid chromatography fluorescence detection method is ${0.3\mu }\mathrm{g}/\mathrm{L}$ , andthe quantitative limit is $1\mathrm{{\mug}}/\mathrm{L}$ ; After derivatization with nitrite, thestability of the derivative is high, and the measurement error is smallwithin 7 days; The recovery rate of nitrite spiking is between90.29%-102.60%, and the precision is between 0.71%-3.66%. Conclusion Thedetermination of nitrite in drinking water by high-performance liquidchromatography fluorescence detection method has the characteristics ofaccuracy and convenience, providing important technical support fordrinking water safety monitoring.

Objective To compare the diagnostic value and healtheconomic value of rapid detection of mycobacterium tuberculosis andrifampicin resistance (XpertMTB/RIF), mycobacterium nucleic acidPCR-fluorescent probe detection (MTB-NTM-PCR) and RNA isothermalamplification real-time fluorescence detection (SAT-TB) in detectingbronchial alveolar lavage fluid (BALF) in smear-negative pulmonarytuberculosis Be worth. Methods A retrospective analysis was conducted on100 patients with clinically diagnosed pulmonary tuberculosis butnegative sputum smears admitted to Guiyang Public Health TreatmentCenter from January 2019 to July 2022. All patients had negative sputumsmears for three consecutive times and underwent fiberoptic bronchoscopyin the fiberoptic bronchoscopy room of our hospital. BALF specimens weresimultaneously tested by smear acid-fast staining, GeneXpert MTB/RIF,MTB-PCR and SAT-TB detection methods. Taking the final clinicaldiagnosis of pulmonary tuberculosis as the gold standard, the diagnosticefficiency of the three methods and cost-effectiveness analysis werecalculated. Results The positive rates of XpertMTB/RIF, MTB-PCR andSAT-TB in 100 BALF samples were 53.00%, 43.00% and 35.00%, respectively.Taking clinical diagnosis as the gold standard, the positive rates ofXpertMTB/RIF $\left({{\chi }^{2}= {21.459}, P<{0.001}}\right)$ , MTB-PCR $\left({{\chi }^{2}= {17.695}, P<{0.001}}\right)$ , SAT-TB $\left({{\chi }^{2}= {12.631}, P<{0.001}}\right)$ and clinical diagnosis were statisticallysignificant. The sensitivity of XpertMTB/RIF, MTB-PCR, SAT-TB,XpertMTB/RIF+MTB-PCR, XpertMTB/RIF+SAT-TB, MTB-PCR+SAT-TB and the threecombined detections were 64.20%, 53.09%, 43.21% and 67, respectively ${90}\%,{66.67}\%,{58.02}\%,{69.14}\%$ ; Thespecificity was ${94.74}\%,{100.00}\%,{100.00}\%,{94.74}\%,{94.74}\%,{100.00}\%$ ,94.74%, respectively. ROC analysis showed that The AUC of XpertMTB/RIF,MTB-PCR, SAT-TB, XpertMTB/RIF+MTB-PCR, XpertMTB/RIF+SAT-TB,MTB-PCR+SAT-TB and the combined detection were 0.795, 0.765, 0.716 and0.813, respectively 0.807, 0.790, 0.819. Conclusion In the rapiddetection of negative tuberculosis, it is not recommended to select theabove three tests at the beginning of diagnosis and treatment. In termsof cost effectiveness, MTB-PCR can be used as the preferred diagnosticmethod for smear-negative pulmonary tuberculosis.

New requirements have been put forward for biosafety in the new era, and it is also listed as a top priority. Medical universities are the cradle of medical talents. Microbiology, as an important subject in basic medicine which combine the theory and practice. Based on the biosafety problems existing in microbiology teaching laboratories, it is extremely urgent to optimization. Through analyzing the current situation of microbiology teaching laboratory, this article mainly discusses the current situation and optimization of microbiology teaching laboratories. In line with student-centered teaching conception, contains the safety awareness of teachers and students, laboratory safety management, and existing safety risks, so as to improve the scientific and specification of microbiology teaching laboratories.

Objective To establish a highly specific method for thedetermination of related substances in salbutamol sulfate injection. Methods HPLC was performed on a column packed with spherical end-cappedoctylsilyl silica gel (Hypersil BDS C8 ${4.6}\times {150}\mathrm{\;{mm}},{3\mu}\mathrm{m}$ ) at the flow rate of ${0.6}\mathrm{\;{mL}}/\mathrm{{min}}$ , thedetection wavelength of ${220}\mathrm{\;{nm}}$ and columntemperature of ${25}^{\circ }\mathrm{C}$ by gradientelution using ${3.45}\mathrm{\;g}/\mathrm{L}$ sodiumdihydrogen phosphate dihydrate solution (adjust to $\mathrm{{pH}}$ 3.0 with phosphoric acid)as mobile phase A, 10 volumes of methanol and 90 volumes of acetonitrileas mobile phase B. Results The chromatograph showed good specificity ofthe peaks of main components and 15 impurities, and the methodverification of 6 of the impurities showed good linear, repeatabilityand recovery. Conclusion The chromatographic peaks of the maincomponents in salbutamol can be completely separated from the 15impurities. The established method is highly specific, easy to operateand can be used for the inspection of related substances in salbutamolsulfate injection.

This article aims to study the influence of electromagnetic interference on the testing of electric energy meters and corresponding protective measures. By combining experimental and theoretical analysis, this study focuses on the impact of electromagnetic interference on the accuracy of electric energy meter testing, including measurement errors, data instability, and equipment damage. Based on these factors, this article proposes protective measures against electromagnetic interference, including the application of physical shielding technology, reasonable design of filters, and strict attention to the testing of electric energy meters. The results indicate that electromagnetic interference can lead to increased errors in electric energy meter testing, which can cause malfunctions and even incorrect operations. To minimize the impact of electromagnetic interference, this article proposes a series of effective protective measures, including reasonable wiring, installation of filters, and use of shielded cables. These measures have achieved good results in practical applications and significantly improved the accuracy and stability of electric energy meter testing.

As an important component of the new energy vehicle field, fuel cell vehicles are powered by the process of hydrogen gas passing through fuel cells to generate electricity. The quality of hydrogen directly affects the efficiency and lifespan of fuel cells, therefore ensuring the high quality of hydrogen is crucial. This article comprehensively explores the relationship between fuel cell vehicles and hydrogen quality, existing hydrogen quality detection technologies and their limitations, and focuses on several new rapid detection technologies, including hydrogen sensor technology, spectral analysis technology, and mass spectrometry analysis technology, as well as their applications in hydrogen quality detection of fuel cell vehicles.

With the rapid development of technology, traditional building material testing methods face many challenges, such as low efficiency, high cost, and insufficient accuracy. Therefore, introducing intelligent technologies such as artificial intelligence, machine learning, and the Internet of Things has become a key way to improve the efficiency and accuracy of building material detection. Artificial intelligence algorithms can achieve intelligent recognition and evaluation of building materials through a large amount of data learning and training, thereby improving the accuracy and speed of detection. At the same time, the application of Internet of Things technology makes the process of building material testing more intelligent and automated, achieving real-time monitoring and data transmission. In addition, the application of machine learning algorithms has also provided new ideas and methods for building material detection, further improving the accuracy and reliability of detection through deep data analysis and pattern recognition. Therefore, applying intelligent technology to material testing in construction projects is expected to bring revolutionary changes to the construction industry.

Objective Study why nicotinamide is transformed tonicotinic acid occurred when detect vitamin ${\mathrm{B}}_{3}$ in milk powdercontaining lactic acid bacteria by GB 5009.89-2016 high performanceliquid chromatography method, and its mechanism was discussed. MethodsThe samples were pretreated according to standard procedures, and theeffects of the placement time of the sample extraction solution, theplacement time of the sample solution before acid hydrolysis and the $\mathrm{{pH}}$ value of acidhydrolysis were investigated by single factor test. Results Thetransformation of nicotinamide to nicotinic acid occurred in theplacement step after the sample was dissolved and before acidhydrolysis, but after adjusting the pH value to 1.7 specified in thestandard for acid hydrolysis, the transformation was completelyinhibited. Conclusion If you want to detect the content of nicotinicacid or nicotinamide separately in samples containing lactic acidbacteria, you need to adjust the $\mathrm{{pH}}$ value to 1.7 when thesample is dissolved to inhibit the transformation of nicotinamide tonicotinic acid.

Laboratory is an important structure in the field of health inspection, and the management level of laboratory directly affects the effect of disease control and prevention. In recent years, with the vigorous development of the laboratory field, the emergence of many new laboratory reagents and laboratory technologies has effectively improved the efficiency of clinical laboratory, but it also poses new challenges to the development of existing laboratory management. The lack of reagent management system, the lack of talent team construction and the inability of information technology advantages are one of the practical difficulties of laboratory management at this stage. It is difficult to avoid the influence of human factors on the quality of inspection, and it is impossible to promote the high-quality development of inspection work. In recent years, with the development of emerging technology industry, emerging technology has potential value in the optimization management of laboratory. This paper reviews four emerging technologies, namely automation pipeline, artificial intelligence technology, cloud management platform and virtual simulation, aiming to solve the problem of lack of reagent management system in traditional laboratory inspection management and difficulty in highlighting the advantages of information technology. So as to promote the inspection laboratory management system update iteration, towards the direction of digital, scientific development.