Objective Exploring the influence of crystal form of ceftriaxone sodium on the quality of ceftriaxone sodium for injection products. Methods Analyze the relationship and reasons between crystal form and product quality by comparing the changes in polymer content of different crystal form products after long-term and accelerated testing. Results There are differences in the quality stability of different crystal forms of ceftriaxone sodium products. Conclusion Production enterprises should pay attention to the production process and choose the optimal crystal form to improve product quality

Based Perchlorate is a new type of pollutant in drinkingwater, which is harmful to human health. The newly promulgated“Standards for Drinking Water Quality”(GB 5749-2022) has been listed asan expanded indicator. The uncertainty of determination of perchloratein drinking water by ion chromatography was evaluated, and the factorsaffecting the accuracy of the result were determined. On the StandardTest Method for Drinking Water Part 5: Inorganic Nonmetallic Indicators(GB/T 5750.5-2023), the perchlorate in drinking water was measured byion chromatography, and the uncertainty introduced in each step wasanalyzed and calculated. And evaluate its expanded uncertainty. Theperchlorate concentration in drinking water was ${0.101}\mathrm{{mg}}/\mathrm{L}$ and theextended uncertainty was ${0.005}\mathrm{{mg}}/\mathrm{L}\left({k =2}\right)$ . The measurement uncertainty is mainly introducedfrom six aspects, namely, the standard material itself, the preparationof standard working fluids, the preparation of series of standardworking fluids, the determination of sample repeatability, the recoveryrate and the main equipment. The most important factor affecting thetotal uncertainty is the uncertainty introduced in the preparationprocess of standard series working fluids.

This paper aims to discuss the key points of quality control of on-site testing in mine safety inspection laboratory, including the quality and skills of analysts, the management and maintenance of instruments and equipment, the specification of sample management, and the condition control of environmental facilities. Through the implementation of a strict quality control system and the application of highly automated inspection technology, the accuracy and trust of inspection data can be significantly improved. Formulate specific requirements and implementation strategies for laboratory personnel training, instrument maintenance system, sample management process and environmental condition control, so as to comprehensively improve the quality of on-site testing work.

Grain and oil safety is related to the foundation of the safety of the entire food chain, and the testing of grain and oil institutions provides important technical support for government supervision. Quality control lies at the core of institutional testing, which not only ensures the accuracy and reliability of testing data, but also provides basic guarantee for establishing a scientific and sound testing system in testing institutions. This paper summarizes the main methods, monitoring links, and analyzes existing problems and challenges of quality control in grain and oil testing institutions. It proposes four suggestions for improving the further effectiveness of quality controlto provide reference for peers.

Objective This article mainly introduces three methods for measuring pitting depth: metallographic method, micrometer method and microscopy method, and discusses their differences in different pitting conditions and their influence on the measurement results. Methods Pitting pits on the surface of carbon steel and stainless steel were respectively measured by using these three measuring methods. and the measured results were analyzed and discussed. Results By comparing the measurement results, we can see that the metallographic method is more accurate, but it is destructive. The micrometer method is only suitable for wide and shallow pitting pits. The microscope method is not only suitable for wide and shallow pitting pits, but also for the small pit bottom. Conclusion (1) For wide and shallow pitting pits, metallographic method, micrometer method and microscopic method are applicable and the results are consistent; (2) For the small pitting pit at the bottom, metallography and microscopy are more suitable and the results are consistent; (3) When the corrosion depth is measured by metallographic, microscope and micrometer methods, the thickness reduction caused by uniform corrosion should be taken into account and the results should be corrected, especially in the case of more obvious uniform corrosion.

Objective Compare the performance differences of threeprotein content determination kits (Lowry method of Aimei, BCA method ofKangwei, and BCA method of Thermo Fisher) in detecting micro $\left({0 \sim {20\mu}\mathrm{g}/\mathrm{{mL}}}\right)$ protein. Select the mostaccurate and reliable reagent kit for the detection of trace proteinsamples. Methods Use these three test kits to detect micro proteincontent, compare their accuracy, sensitivity, linearity andrepeatability, and evaluate their equivalence. Results The recoveryrates of the three test kits for detecting trace amounts $\left({{1.25}\sim {20\mu}\mathrm{g}/\mathrm{{mL}}}\right)$ of protein were all withinthe range of 75%~120%, demonstrating qualified accuracy; Thermo FisherBCA meets the acceptable precision range (RSD $\leq 6\%$ ) in the range of ${2.5\mu }\mathrm{g}/\mathrm{{mL}}$ to ${20\mu }\mathrm{g}/\mathrm{{mL}}$ ,while Aimei Lowry and Kangwei BCA meet the acceptable precision range(RSD $\leq 6\%$ ) in the range of ${5\mu }\mathrm{g}/\mathrm{{mL}}$ to ${20\mu }\mathrm{g}/\mathrm{{mL}}$ ,demonstrating good repeatability; the correlation coefficient ${\mathrm{R}}^{2}$ of the standard curvesof the three test kits $\left({0\sim {20}\mathrm{{\mu g}}/\mathrm{{mL}}}\right)$ are all higherthan 0.980 . The linearity of Aimei Lowry is slightly poor, with ${\mathrm{R}}^{2}$ of 0.981 . The linearityof Kangwei BCA is qualified, with ${\mathrm{R}}^{2}$ of 0.991 . The linearityof Thermo Fisher BCA is the best, with ${\mathrm{R}}^{2}$ of 0.993; The abovemethodological validation results indicate that the minimumquantification limits for the sensitivity of the three test kits are ${5\mu }\mathrm{g}/\mathrm{{mL}}$ forthe Aimei Lowry method, ${5\mu}\mathrm{g}/\mathrm{{mL}}$ for the Kangwei BCA method, and ${2.5\mu }\mathrm{g}/\mathrm{{mL}}$ for theThermo Fisher BCA method, respectively; Paired curves of values detectedby three reagent kits for the same series of BSA concentrations andtheir correlation coefficients were all higher than 0.990 . ConclusionThrough experiments, we found that each reagent kit exhibited differentperformance in different concentrations of BSA samples, among which theThermo Fisher BCA method performed the best in terms of accuracy andrepeatability, and there was a certain correlation between these threemethods.

This study aims to respond to the call of the Dali Bai Autonomous Prefecture Ecological Environment Bureau to intensify monitoring of the Erhai Lake area and its main rivers, and conduct long-term and continuous monitoring of the chemical oxygen demand (COD) and dissolved oxygen (DO) in the river channel entering Erhai Lake in Dali Manjiang. By deeply analyzing nearly 170 sets of monitoring data and drawing a relationship diagram between COD and DO, we have a deep understanding of the relationship between these two water quality indicators in the river channel entering Erhai Lake in Dali Manjiang. This study not only provides strong data support for further monitoring and control of the river channel entering Erhai Lake, but also provides a scientific basis for promoting the protection of Erhai Lake. By revealing the relationship between COD and DO, it is possible to more accurately assess the water quality of the river channel entering Erhai Lake, so as to more effectively formulate and implement environmental protection measures and contribute to the sustainable and healthy development of the ecological environment of Erhai Lake.

The purpose is to study the vertical linear uncertainty of ultrasonic flaw detectors. Firstly, introduce the specific instrument models and technical parameters, analyze the basis and methods for evaluating the vertical linear uncertainty of ultrasonic flaw detectors, and conduct uncertainty evaluation through modeling. Finally, issue a vertical linear uncertainty report and propose the key points for calibrating the ultrasonic flaw detector calibration device. Intended to provide reference for ultrasonic detection personnel, master the exploration skills of vertical linear uncertainty of ultrasonic flaw detectors, truly optimize the quality and performance of ultrasonic flaw detectors, and truly play its functional role.

Objective To establish a spectrophotometric evaluationmethod for determining sulfur dioxide uncertainty in formaldehydeabsorption fluid. Methods According to JJF 1059-2012, Evaluation andrepresentation of measurement Uncertainty, establish a mathematicalmodel to calculate each uncertainty component and synthetic uncertainty. Results The uncertainty introduced by repeated measurement is 0.27%; thestandard curve preparation is 0.40%; the standard curve drawing andfitting is 0.20%; the instrument measurement is 0.35%; the syntheticrelative standard uncertainty is 0.63%, and the extended uncertainty is ${0.008}\mathrm{{mg}}/\mathrm{L}$ . Conclusion This method is suitable for measuring the uncertaintyassessment of sulfur dioxide in formaldehyde absorption fluid.

Objective To study the application of cell morphology inblood smear and automatic blood cell analyzer detection in blood routineexamination. Methods A analys was was conducted on 180 patients withsuspected Macrocellular anemia at Yishui County People’s Hospital fromFebruary 2020 to February 2023. The positive detection rates of diseasewere statwastically analyzed for individual and combined tests, and thepositive detection rates of toxic particles/vacuolar degeneration,nucleated red blood cells, and atypical lymphocytes were alsostatwastically analyzed for individual and combined tests, statwasticalanalyswas of diagnostic efficacy for individual and joint testing. Results The positive detection rates of monocytes, neutrophils,lymphocytes, basophils, and eosinophils detected by the combination ofblood smear cell morphology and fully automated blood cell analyzer werehigher than those detected alone $\left({P<{0.05}}\right)$ . The positive detection rates of toxicparticle/vacuolar degeneration, nucleated red blood cells, and atypicallymphocytes detected by the combination of blood smear cell morphologyand fully automated blood cell analyzer were higher than those detectedalone $\left({P <{0.05}}\right)$ .The sensitivity, specificity, accuracy, and negative predictive value ofthe combined detection of blood smear cell morphology and fullyautomated blood cell analyzer were higher than those of individualdetection $\left({P<{0.05}}\right)$ . Conclusion The value of combined detectionof blood smear cell morphology and fully automated blood cell analyzerin blood routine examination is higher, so is worthy of promotion.