Objective To explore the determination of cyanide in cassava starch by a continuous flow online distillation method. Methods Cassava starch was extracted with sodium hydroxide solution, filtered and then quantitatively analyzed with a continuous flow analyzer. The effects of extraction concentration, ultrasonic time, sample size and separation method on cyanide determination were investigated. Results 2.0 g samples were directly weighed and added to 100 mL 2 g/L sodium hydroxide solution for ultrasonic extraction for 20 min, and filtered with qualitative filter paper. The filtrate was quantitatively determined with a continuous flow analyzer. The linear relationship between cyanide concentration of 0 mg/L and 0.20 mg/L was good, r ≥ 0.999. The detection limit of the method was 0.01 mg/kg, the limit of quantitation was 0.03 mg/kg, the relative standard deviation was 0.26%-1.52%, and the standard addition recovery rate was 90.36%-104.19%. Conclusion The continuous flow online distillation method has the advantages of low detection limit, good repeatability, automatic operation, reduction of manual errors, and high analysis speed, which is beneficial to improve work efficiency, and can be used for batch detection of cyanide in cassava starch.

COVID-19 ; Cardiovascular Diseases ; Cardiovascular System ; Humans ; SARS-CoV-2

Objective To explore the applications and effect of experience-based health education in maternal nursing in community.Methods According to the random number table,150 women pregnant for the first time were divided into control group and observation group with 75 in each group. In the control group,the traditional method for health education was used and in the observation group the experience-based teaching based on traditional health education.The two groups were compared in terms of the awareness rate of knowledge about maternal and infant health care and the incidence of postpartum depression.Result The awareness of knowledge about maternal and infant health care in the observation group was significantly higher than that of the control group and the incidence of postpartum depression in the observation group was significantly lower than that of the control group(P<0.01).Conclusion Experience-based health education can improve the level of knowledge about maternal and infant health care and reduce the incidence of maternal postpartum depression.