Objective This study aims to establish an efficient andaccurate method for the determination of zinc content in mineral samplesbased on the flame absorption method of atomic absorptionspectrophotometer, in order to meet the growing demand for metal elementdetection in various fields. Methods The zinc content was determined byatomic absorption spectrophotometer, combined with pretreatment samples,experimental procedure, optimization of instrument measurementconditions and establishment of standard curve. Results The establishedmethod has high precision and accuracy, the recovery rate is99.1%~99.9%, and the correlation coefficient is 0.9998 . The detectionlimit of the method was ${0.1}\mathrm{{\mug}}/\mathrm{{mL}}$ , indicating that the method had goodquantitative analysis ability. Conclusion The method has not only highsensitivity and selectivity, but also simple operation and reliableresults, which is of great significance for environmental protection andoptimal utilization of resources.

Objective To establish an optimal method for thedetermination of available copper, iron, manganese and zinc in soil inSanpu. Methods AB-DTPA leaching and inductively coupled plasmaspectrometry were used to determine the available $\mathrm{{Cu}},\mathrm{{Fe}},\mathrm{{Mn}}$ and $\mathrm{{Zn}}$ in soilsimultaneously. Results The detection limit and precision met theanalysis requirements, and the high accuracy of copper, iron andmanganese were in the concentration range of ${0.50}\sim {100}\mathrm{{mg}}/\mathrm{L}$ ,and zinc was in the concentration range of ${0.25}\sim {10.0}\mathrm{{mg}}/\mathrm{L}$ .The linear relationship was good, and the correlation coefficients wereall above 0.999 . The detection range of the method was in the range of ${0.06}\sim {0.69}\mathrm{{mg}}/\mathrm{{kg}}$ ,and the blank test results were stable. The precision of the methods wasless than 5.0%, and the parallel differences of the samples were allwithin the qualified range. The available iron, manganese and copper,zinc in the sample are different by one to two orders of magnitude, andthe determination can still obtain accurate results. Conclusion Thedetection limit and precision of this method meet the requirements ofanalysis, and the accuracy is high, which is suitable for the detectionof available copper, iron, manganese and zinc in soil.

With the rapid development of China's automobile industry, vehicle engineering talents are in great demand. College vehicle engineering laboratory is an important place for vehicle engineering specialty to carry out basic and critical education and teaching work, so it is increasingly important to improve the construction level of vehicle engineering specialty laboratory. At present, equipment maintenance and management measures are not in place in vehicle engineering laboratories, which leads to high failure rate and low utilization rate of laboratory equipment. Based on the analysis of equipment failure in the laboratory of vehicle engineering specialty, this paper puts forward the strategy of periodic maintenance, equipment maintenance and management measures such as preventive maintenance strategies, building equipment management systems, and improving use specifications provide ideas for further improving the construction level of vehicle engineering professional laboratories.

Objective To investigate the disintegration and dissolutionproperties of alprogesterone as a feed additive under differentenvironmental conditions, and to develop a suitable tablet for pig farmfeeding. Methods The prescription was screened by 3-factor and 3-levelorthogonal test, and the disintegration time, dissolution and appearancequality of the tablets were tested. Results The disintegration time ofthe optimized allyl gestrel was $7\sim {15}\mathrm{\;{min}}$ , which was better than $2 \sim 5\mathrm{\;{min}}$ of conventionaltablets. Conclusion The optimized dissolution and content of allylgestrel meet the standard, which is convenient for sows to consume andcan meet the feeding needs of pig farms.

Objective In order to prevent the volatilization loss of volatile oil components such as bornyl acetate in Amomum villosum powder during storage, a reasonable and effective storage conditions and storage validity period of Amomum villosum powder were developed, so as to improve the quality stability and food efficiency of terminal products. Methods The samples of Amomum villosum powder in different storage environments [high temperature (35°C), cool (10~15°C) and cold storage (0~5°C)] were sampled every week, and the contents of bornyl acetate and volatile oil were determined respectively. Finally, the trend analysis was carried out according to the content results. Results According to the experimental results, the contents of bornyl acetate and volatile oil in Amomum villosum powder under different storage conditions were quite different. The contents of bornyl acetate and volatile oil in Amomum villosum powder under cold storage conditions were slightly higher than those under shade conditions, but they were significantly higher than those under high temperature storage conditions. Conclusion The research results provide an in-depth analysis of the changes in the main components of Amomum villosum powder under different storage conditions, providing important reference for enterprises to choose the storage method of Amomum villosum powder.

Objective To study the bacteriological test method ofsputum samples and the effect of clinical infection. Methods A total of240 samples were collected from May 2019 to May 2020. After the twogroups, the conventional test samples were collected by sputum culture,and the test sample was improved by bacteriology and sputum culture,comparing the sample quality and test results. Results According to thecomparison analysis, the sample quality, disease detection rate andstrain positive rate of the study group were ideal, and the group weredominant $\left({P<{0.05}}\right)$ . Conclusion The implementation ofbacteriological test of sputum specimens can accurately detect patients,and the proportion of clinical infection is ideal, so it has goodimplementation effect and clinical application value.

Objective To improve the detection method of bulk densityof powder materials, in order to improve the accuracy and efficiency ofthe detection results of cement. Methods Through the improvement ofauxiliary metal rod rotation technology at the pipe to loosen thematerial and make it fall naturally, the detection data before and afterthe improvement of cement volume density detection technology werecompared to find a more environmentally friendly, faster and accuratetest method. Results The improved test data did not fluctuate due to theequipment displacement, and the cement bulk density remained at ${1.03}\mathrm{\;g}/{\mathrm{{cm}}}^{3}$ inthe loose state, the whole test process took a short time ( ${1.5}\mathrm{\;{min}}$ ), there was no dustin the test process, and the test results did not exceed the errorrange, all of which were better than the measured data before theimprovement. Conclusion The improved test method can improve theaccuracy and precision of cement performance test more scientifically,and can make the test results closer to the real value, which isfeasible, has certain social and economic value, and is worthpopularizing.

With the rapid development of the discipline construction and scientific research level in universities, the safety management of biological laboratories in universities is facing increasingly severe challenges. This paper takes the biological laboratory of a foreign university as the research object, and draws valuable experience from the biological laboratory safety management practice of the university through the analysis of the laboratory safety management organization and management system, which can provide useful reference for the safety construction, network management and training system of biological laboratories in China. It is helpful to improve the standardization and effectiveness of biological laboratory safety management.

Objective To optimize the conditions for the determinationof total $\alpha$ and total $\beta$ radioactivity in drinking water andimprove the accuracy of the experiment. Methods On the basis ofmeasuring the residue content in drinking water, the total $\alpha$ and $\beta$ radioactivity values in drinkingwater were determined by improving evaporation and concentration processand optimizing reagent conditions. Results In this study, the amount ofresidue, $\alpha$ and $\beta$ radioactivity increased, and thetest time was reduced compared with the traditional method. Conclusion The method significantly improves the accuracy of results and testingefficiency and can be further optimized. It provides certain researchsignificance in the quality control of laboratory measurements.

Objective This study aims to compare and evaluate theperformance and applicability of two ammonia $\left({\mathrm{{NH}}}_{3}\right)$ detection methods in the field and laboratory. Methods The C16 portable ${\mathrm{{NH}}}_{3}$ gas detectorand GBZ/T 160.29-2004 ammonia Nessler’s reagent spectrophotometricmethod were used to perform 10 repeated measurements of 5 differentconcentrations $\left({{9.3}\sim {148.8}\mathrm{{mg}}/{\mathrm{m}}^{3}}\right)$ of ${\mathrm{{NH}}}_{3}$ standardgases. Results The results showed that the C16 portable detectorexhibited a highly linear relationship $\left({r ={0.9998}}\right)$ in fieldapplications, which was highly correlated with the concentration ofstandard gases; The GBZ/T 160.29-2004 method provides higher precisionmeasurement values in laboratory analysis. The relative standarddeviation and relative error of both methods are less than ±5%,demonstrating good precision and accuracy. The research conclusionindicates that the C16 portable detector is suitable for rapid on-sitedetection and emergency response, while the GBZ/T 160.29-2004 method ismore suitable for laboratory analysis that requires high precision. Conclusion This study provides a scientific basis for selectingappropriate ${\mathrm{{NH}}}_{3}$ detection methods, which is of great significance for improving thequality of environmental monitoring and occupational healthassessment.